G2Cdb::Gene report

Gene id
G00001636
Gene symbol
PRDX1 (HGNC)
Species
Homo sapiens
Description
peroxiredoxin 1
Orthologue
G00000387 (Mus musculus)

Databases (9)

Curated Gene
OTTHUMG00000007738 (Vega human gene)
Gene
ENSG00000117450 (Ensembl human gene)
5052 (Entrez Gene)
115 (G2Cdb plasticity & disease)
PRDX1 (GeneCards)
Literature
176763 (OMIM)
Marker Symbol
HGNC:9352 (HGNC)
Protein Expression
4682 (human protein atlas)
Protein Sequence
Q06830 (UniProt)

Synonyms (1)

  • NKEFA

Diseases (1)

Disease Nervous effect Mutations Found Literature Mutations Type Genetic association?
D00000027: Hepatocellular carcinoma N N (16254121) No mutation found (N) N

References

  • Rare allelic imbalances, but no mutations of the PRDX1 gene in human hepatocellular carcinomas.

    Gisin J, Perren A, Bawohl M and Jochum W

    Department of Pathology, University of Zürich, Schmelzbergstrasse 12, CH-8091 Zürich, Switzerland.

    Allelic losses on chromosome 1p are frequent in hepatocellular carcinoma (HCC), suggesting the presence of a tumour suppressor gene in this region. The gene for peroxiredoxin 1 (PRDX1), an antioxidant enzyme, has been mapped to 1p34.1. Mice lacking PRDX1 develop HCC with high frequency. Because oxidative stress has been implicated in the pathogenesis of HCC, this study was designed to determine whether the PRDX1 gene is mutated in human HCC using loss of heterozygosity (LOH) analysis, polymerase chain reaction/denaturing gradient gel electrophoresis, and DNA sequencing. LOH of at least one of four microsatellite markers within 0.8 Mb of the PRDX1 gene was seen in three of 34 informative HCCs, but no mutations or polymorphisms in the translated exons 2-6 of the PRDX1 gene were found. These results suggest that genetic alterations of the PRDX1 locus are rare events in human HCC, indicating that other genes on chromosome 1p contribute to liver carcinogenesis.

    Journal of clinical pathology 2005;58;11;1229-31

Literature (69)

Pubmed - human_disease

  • Rare allelic imbalances, but no mutations of the PRDX1 gene in human hepatocellular carcinomas.

    Gisin J, Perren A, Bawohl M and Jochum W

    Department of Pathology, University of Zürich, Schmelzbergstrasse 12, CH-8091 Zürich, Switzerland.

    Allelic losses on chromosome 1p are frequent in hepatocellular carcinoma (HCC), suggesting the presence of a tumour suppressor gene in this region. The gene for peroxiredoxin 1 (PRDX1), an antioxidant enzyme, has been mapped to 1p34.1. Mice lacking PRDX1 develop HCC with high frequency. Because oxidative stress has been implicated in the pathogenesis of HCC, this study was designed to determine whether the PRDX1 gene is mutated in human HCC using loss of heterozygosity (LOH) analysis, polymerase chain reaction/denaturing gradient gel electrophoresis, and DNA sequencing. LOH of at least one of four microsatellite markers within 0.8 Mb of the PRDX1 gene was seen in three of 34 informative HCCs, but no mutations or polymorphisms in the translated exons 2-6 of the PRDX1 gene were found. These results suggest that genetic alterations of the PRDX1 locus are rare events in human HCC, indicating that other genes on chromosome 1p contribute to liver carcinogenesis.

    Journal of clinical pathology 2005;58;11;1229-31

Pubmed - other

  • Protein engineering of the quaternary sulfiredoxin.peroxiredoxin enzyme.substrate complex reveals the molecular basis for cysteine sulfinic acid phosphorylation.

    Jönsson TJ, Johnson LC and Lowther WT

    Center for Structural Biology and Department of Biochemistry, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157, USA.

    Oxidative stress can damage the active site cysteine of the antioxidant enzyme peroxiredoxin (Prx) to the sulfinic acid form, Prx-SO(2)(-). This modification leads to inactivation. Sulfiredoxin (Srx) utilizes a unique ATP-Mg(2+)-dependent mechanism to repair the Prx molecule. Using selective protein engineering that involves disulfide bond formation and site-directed mutagenesis, a mimic of the enzyme.substrate complex has been trapped. Here, we present the 2.1 A crystal structure of human Srx in complex with PrxI, ATP, and Mg(2+). The Cys(52) sulfinic acid moiety was substituted by mutating this residue to Asp, leading to a replacement of the sulfur atom with a carbon atom. Because the Srx reaction cannot occur, the structural changes in the Prx active site that lead to the attack on ATP may be visualized. The local unfolding of the helix containing C52D resulted in the packing of Phe(50) in PrxI within a hydrophobic pocket of Srx. Importantly, this structural rearrangement positioned one of the oxygen atoms of Asp(52) within 4.3 A of the gamma-phosphate of ATP bound to Srx. These observations support a mechanism where phosphorylation of Prx-SO(2)(-) is the first chemical step.

    Funded by: NIGMS NIH HHS: R01 GM072866, R01GM072866

    The Journal of biological chemistry 2009;284;48;33305-10

  • The antioxidant enzyme Prdx1 controls neuronal differentiation by thiol-redox-dependent activation of GDE2.

    Yan Y, Sabharwal P, Rao M and Sockanathan S

    The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.

    The six-transmembrane protein GDE2 controls the onset and progression of spinal motor neuron differentiation through extracellular glycerophosphodiester phosphodiesterase metabolism. Although this process is likely to be tightly regulated, the relevant mechanisms that modulate its activity are unknown. Here we show that the antioxidant scavenger peroxiredoxin1 (Prdx1) interacts with GDE2, and that loss of Prdx1 causes motor neuron deficits analogous to GDE2 ablation. Prdx1 cooperates with GDE2 to drive motor neuron differentiation, and this synergy requires Prdx1 thiol-dependent catalysis. Prdx1 activates GDE2 through reduction of an intramolecular disulfide bond that bridges its intracellular N- and C-terminal domains. GDE2 variants incapable of disulfide bond formation acquire independence from Prdx1 and are potent inducers of motor neuron differentiation. These findings define Prdx1 as a pivotal regulator of GDE2 activity and suggest roles for coupled thiol-redox-dependent cascades in controlling neuronal differentiation in the spinal cord.

    Funded by: NINDS NIH HHS: R01 NS046336, R01 NS046336-05A1, R01 NS046336-06, R56 NS046336, R56 NS046336-05

    Cell 2009;138;6;1209-21

  • Prx1 enhances androgen receptor function in prostate cancer cells by increasing receptor affinity to dihydrotestosterone.

    Chhipa RR, Lee KS, Onate S, Wu Y and Ip C

    Department of Cancer Prevention and Control, Roswell Park Cancer Institute, Buffalo, NY 14263, USA.

    Androgen receptor (AR) signaling plays a critical role in the development and progression of prostate cancer. It has been reported previously that peroxiredoxin-1 (Prx1), a member of a novel family of peroxidases, interacts physically with AR to enhance AR transactivation of target genes. In the present study, we evaluated the biological significance of Prx1 in modulating dihydrotestosterone (DHT)-stimulated growth and AR target gene expression of prostate cancer cells. We also investigated the mechanism by which Prx1 might potentiate AR signaling. The contribution of Prx1 was assessed mainly by using the approach of stable Prx1 knockdown. The major observations are as follows: (a) A low level of Prx1 desensitizes cells to growth stimulation and AR target gene induction by DHT, such that exposure to a higher level of DHT is required to reach the same magnitude of response when Prx1 is depressed; (b) Prx1 increases the affinity of AR to DHT and decreases the rate of DHT dissociation from the occupied receptor; (c) Prx1 enhances the NH2 terminus and COOH terminus interaction of AR; a stronger N-C interaction is consistent with a more robust AR activation signal by keeping DHT tight in the ligand-binding pocket; (d) the stimulatory effects of Prx1 on AR ligand binding affinity and AR N-C interaction are manifested regardless of a wild-type or mutant AR. The above findings led us to believe that Prx1 may be a therapeutic target in blocking the transition of prostate cancer from an androgen-dependent to an androgen-refractory phenotype.

    Funded by: NCI NIH HHS: P01 CA126804, P01 CA126804-02, P30 CA016056, P30 CA16056

    Molecular cancer research : MCR 2009;7;9;1543-52

  • Peroxiredoxin I contributes to TRAIL resistance through suppression of redox-sensitive caspase activation in human hepatoma cells.

    Song IS, Kim SU, Oh NS, Kim J, Yu DY, Huang SM, Kim JM, Lee DS and Kim NS

    Genome Research Center, Korea Research Institute of Bioscience and Biotechnology, Yusong, Daejeon, Republic of Korea.

    Reactive oxygen species (ROS) have been implicated in tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) resistance of many cancers. We evaluated the role of peroxiredoxin (Prx) I in TRAIL resistance governed by coupling of nicotinamide adenosine dinucleotide phosphate oxidase (Nox)-derived ROS signaling with the p38 mitogen-activated protein kinase (MAPK)/caspase-signaling cascade in liver cancer cells. Upregulated Prx I expression was found in neoplastic regions of human patient liver, and Prx I knockdown resulted in accelerated TRAIL-induced cell death in SK-Hep-1 human hepatoma cells. The TRAIL cytotoxicity by Prx I knockdown was dependent on activation of caspase-8/3 cascades, which was ablated by addition of inhibitors for p38 MAPK, ROS or Nox, suggesting the association with Nox-driven redox signaling. Furthermore, we found that Nox4 was constitutively expressed in both SK-Hep-1 cells and tumor regions of patient livers, knockdown of Nox4 expression could alleviate ROS generation and TRAIL-mediated cytotoxicity. In accordance with previous findings, increased activation of both p38 MAPK and caspase cascades by Prx I knockdown was inhibited by either Nox4 knockdown or SB203580 addition. Collectively, these data suggest that Prx I functions to block propagation of Nox-derived ROS signaling to the p38 MAPK/caspase/cell death cascade during TRAIL treatment and also provides a molecular mechanism by which Prx I contributes to TRAIL resistance in liver cancers.

    Carcinogenesis 2009;30;7;1106-14

  • Peroxiredoxin I is overexpressed in oncocytic lesions of salivary glands.

    Demasi AP, Furuse C, Altemani A, Junqueira JL, Oliveira PR and Araújo VC

    Department of Oral Pathology, São Leopoldo Mandic Research Center, SP, Brazil. demasiap@gmail.com

    Background: Oncocytic lesions, particularly frequent in the salivary glands, are characterized by cells with an atypical accumulation of mitochondria. This accumulation has been recognized as a compensatory mechanism to intrinsic functional defects of these organelles, resulting in energy production impairment and increased generation of reactive oxygen species (ROS), including hydrogen peroxide (H(2)O(2)). Peroxiredoxin I (Prx I) is a H(2)O(2) scavenging protein and the expression of its yeast homolog was reported to be influenced by mitochondrial function.

    Methods: In this study, we evaluated Prx I expression in oncocytic lesions of salivary glands by immunohistochemistry.

    Results: Our results showed that Prx I is overexpressed in oncocytes regardless of the salivary gland lesion where they appear.

    Conclusions: These results suggest that Prx I expression in oncocytes is related to its ability to decompose mitochondrial-derived H(2)O(2) and that it could provide to the cells a protective role in an environment that, by continuously producing potential DNA-damaging ROS, predisposes to genome instability and cellular transformation.

    Journal of oral pathology & medicine : official publication of the International Association of Oral Pathologists and the American Academy of Oral Pathology 2009;38;6;514-7

  • Novel protective mechanism against irreversible hyperoxidation of peroxiredoxin: Nalpha-terminal acetylation of human peroxiredoxin II.

    Seo JH, Lim JC, Lee DY, Kim KS, Piszczek G, Nam HW, Kim YS, Ahn T, Yun CH, Kim K, Chock PB and Chae HZ

    School of Biological Sciences and Technology, Chonnam National University, Gwangju 500-757, Korea.

    Peroxiredoxins (Prxs) are a group of peroxidases containing a cysteine thiol at their catalytic site. During peroxidase catalysis, the catalytic cysteine, referred to as the peroxidatic cysteine (C(P)), cycles between thiol (C(P)-SH) and disulfide (-S-S-) states via a sulfenic (C(P)-SOH) intermediate. Hyperoxidation of the C(P) thiol to its sulfinic (C(P)-SO(2)H) derivative has been shown to be reversible, but its sulfonic (C(P)-SO(3)H) derivative is irreversible. Our comparative study of hyperoxidation and regeneration of Prx I and Prx II in HeLa cells revealed that Prx II is more susceptible than Prx I to hyperoxidation and that the majority of the hyperoxidized Prx II formation is reversible. However, the hyperoxidized Prx I showed much less reversibility because of the formation of its irreversible sulfonic derivative, as verified with C(P)-SO(3)H-specific antiserum. In an attempt to identify the multiple hyperoxidized spots of the Prx I on two-dimensional PAGE analysis, an N-acetylated Prx I was identified as part of the total Prx I using anti-acetylated Lys antibody. Using peptidyl-Asp metalloendopeptidase (EC 3.4.24.33) peptide fingerprints, we found that N(alpha)-terminal acetylation (N(alpha)-Ac) occurred exclusively on Prx II after demethionylation. N(alpha)-Ac of Prx II blocks Prx II from irreversible hyperoxidation without altering its affinity for hydrogen peroxide. A comparative study of non-N(alpha)-acetylated and N(alpha)-terminal acetylated Prx II revealed that N(alpha)-Ac of Prx II induces a significant shift in the circular dichroism spectrum and elevation of T(m) from 59.6 to 70.9 degrees C. These findings suggest that the structural maintenance of Prx II by N(alpha)-Ac may be responsible for preventing its hyperoxidation to form C(P)-SO(3)H.

    The Journal of biological chemistry 2009;284;20;13455-65

  • The effects of acrolein on peroxiredoxins, thioredoxins, and thioredoxin reductase in human bronchial epithelial cells.

    Myers CR and Myers JM

    Department of Pharmacology and Toxicology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA.

    Inhalation is a common form of exposure to acrolein, a toxic reactive volatile aldehyde that is a ubiquitous environmental pollutant. Bronchial epithelial cells would be directly exposed to inhaled acrolein. The thioredoxin (Trx) system is essential for the maintenance of cellular thiol redox balance, and is critical for cell survival. Normally, thioredoxin reductase (TrxR) maintains the cytosolic (Trx1) and mitochondrial (Trx2) thioredoxins in the reduced state, and the thioredoxins keep the peroxiredoxins (Prx) reduced, thereby supporting their peroxidase function. The effects of acrolein on TrxR, Trx and Prx in human bronchial epithelial (BEAS-2B) cells were determined. A 30-min exposure to 5 microM acrolein oxidized both Trx1 and Trx2, although significant effects were noted for Trx1 at even lower acrolein concentrations. The effects on Trx1 and Trx2 could not be reversed by treatment with disulfide reductants. TrxR activity was inhibited 60% and >85% by 2.5 and 5 microM acrolein, respectively. The endogenous electron donor for TrxR, NADPH, could not restore its activity, and activity did not recover in cells during a 4-h acrolein-free period in complete medium. The effects of acrolein on TrxR and Trx therefore extend beyond the duration of exposure. While there was a strong correlation between TrxR inhibition and Trx1 oxidation, the irreversible effects on Trx1 suggest direct effects of acrolein rather than loss of reducing equivalents from TrxR. Trx2 did not become oxidized until > or = 90% of TrxR was inhibited, but irreversible effects on Trx2 also suggest direct effects of acrolein. Prx1 (cytosolic) and Prx3 (mitochondrial) shifted to a largely oxidized state only when >90 and 100% of their respective Trxs were oxidized. Prx oxidation was readily reversed with a disulfide reductant, suggesting that Prx oxidation resulted from lack of reducing equivalents from Trx and not direct reaction with acrolein. The effects of acrolein on the thioredoxin system and peroxiredoxins could have important implications for cell survival, redox-sensitive cell signaling, and tolerance to other oxidant insults.

    Funded by: NIEHS NIH HHS: ES012707, R01 ES012707, R01 ES012707-01, R01 ES012707-02, R01 ES012707-03, R01 ES012707-04, R56 ES012707

    Toxicology 2009;257;1-2;95-104

  • Peroxiredoxin I, platelet-derived growth factor A, and platelet-derived growth factor receptor alpha are overexpressed in carcinoma ex pleomorphic adenoma: association with malignant transformation.

    Demasi AP, Furuse C, Soares AB, Altemani A and Araújo VC

    Department of Oral Pathology, São Leopoldo Mandic Dental Research Center, CEP 13045-610 Campinas, SP, Brazil. demasiap@lge.ibi.unicamp.br

    Carcinoma ex pleomorphic adenoma is a rare salivary gland malignancy. It constitutes an important model for the study of carcinogenesis, as it can display the tumor in different stages of progression, from benign pleomorphic adenoma to frankly invasive carcinoma. Growth signaling pathways undergo continuous activation in human tumors, commonly as a consequence of the overexpression of ligands and receptors such as platelet-derived growth factor and platelet-derived growth factor receptor. Hydrogen peroxide is produced after platelet-derived growth factor receptor activation, and it is essential for the sequential phosphorylation cascade that drives cell proliferation and migration. By their ability to degrade hydrogen peroxide, peroxiredoxins are involved in growth factor signaling regulation and in the oxidative stress response. To verify the potential association of peroxiredoxin I, platelet-derived growth factor-A, and platelet-derived growth factor receptor-alpha with carcinoma ex pleomorphic adenoma progression, we investigated the expression of these molecules in carcinoma ex pleomorphic adenoma showing different degrees of invasion. The peroxiredoxin I, platelet-derived growth factor-A, and platelet-derived growth factor receptor-alpha proteins were present in remnant pleomorphic adenoma to only a small extent, but, collectively, they were highly expressed as soon as the malignant phenotype was achieved and remained at elevated concentrations during progression to the advanced stages of carcinoma ex pleomorphic adenoma. In addition, their locations overlapped significantly, strengthening their connection to this growth-signaling pathway. Our results indicate that carcinoma ex pleomorphic adenoma cells acquire at least 2 significant advantages relative to their normal counterparts: resistance to oxidative stress-induced apoptosis, conferred by high peroxiredoxin I concentrations, and sustained growth, reflecting platelet-derived growth factor-A and platelet-derived growth factor receptor-alpha overexpression.

    Human pathology 2009;40;3;390-7

  • Oxidative stress, telomere length and biomarkers of physical aging in a cohort aged 79 years from the 1932 Scottish Mental Survey.

    Starr JM, Shiels PG, Harris SE, Pattie A, Pearce MS, Relton CL and Deary IJ

    MRC Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Royal Victoria Hospital, Edinburgh EH4 2DN, UK. jstarr@staffmail.ed.ac.uk

    Telomere shortening is a biomarker of cellular senescence and is associated with a wide range of age-related disease. Oxidative stress is also associated with physiological aging and several age-related diseases. Non-human studies suggest that variants in oxidative stress genes may contribute to both telomere shortening and biological aging. We sought to test whether oxidative stress-related gene polymorphisms contribute to variance in both telomere length and physical biomarkers of aging in humans. Telomere lengths were calculated for 190 (82 men, 108 women) participants aged 79 years and associations with 384 SNPs, from 141 oxidative stress genes, identified 9 significant SNPS, of which those from 5 genes (GSTZ1, MSRA, NDUFA3, NDUFA8, VIM) had robust associations with physical aging biomarkers, respiratory function or grip strength. Replication of associations in a sample of 318 (120 males, 198 females) participants aged 50 years confirmed significant associations for two of the five SNPs (MSRA rs4841322, p=0.008; NDUFA8 rs6822, p=0.048) on telomere length. These data indicate that oxidative stress genes may be involved in pathways that lead to both telomere shortening and physiological aging in humans. Oxidative stress may explain, at least in part, associations between telomere shortening and physiological aging.

    Funded by: Biotechnology and Biological Sciences Research Council: S18386; Chief Scientist Office: CZB/4/505, ETM/55; Medical Research Council; Wellcome Trust

    Mechanisms of ageing and development 2008;129;12;745-51

  • Ets regulates peroxiredoxin1 and 5 expressions through their interaction with the high-mobility group protein B1.

    Shiota M, Izumi H, Miyamoto N, Onitsuka T, Kashiwagi E, Kidani A, Hirano G, Takahashi M, Ono M, Kuwano M, Naito S, Sasaguri Y and Kohno K

    Department of Molecular Biology, University of Occupational and Environmental Health, Kitakyushu, Fukuoka, Japan.

    Peroxiredoxins (Prdxs) are thiol-specific antioxidant proteins that are highly expressed in human cancer cells. Prdxs have been shown to be involved in tumor cell proliferation under conditions of microenvironmental stress such as hypoxia. We hypothesized that Prdxs could be categorized into two groups, stress-inducible and non-inducible ones. In this study, we analyzed the promoter activity and expression levels of five Prdx family members in human cancer cells. We found that both Prdx1 and Prdx5 are inducible after treatment with hydrogen peroxide or hypoxia, but that Prdx2, Prdx3, and Prdx4 are not or are only marginally inducible. We also found that Ets transcription factors are the key activators for stress-inducible expression. High-mobility group protein HMGB1 was shown to function as a coactivator through direct interactions with Ets transcription factors. The DNA binding of Ets transcription factors was significantly enhanced by HMGB1. Silencing of Ets1, Ets2, Prdx1, and Prdx5 expression sensitized cells to oxidative stress. These data indicate that transcription of Prdx genes mediated by Ets/HMG proteins might protect cells from oxidative stress.

    Cancer science 2008;99;10;1950-9

  • HDAC6 is a specific deacetylase of peroxiredoxins and is involved in redox regulation.

    Parmigiani RB, Xu WS, Venta-Perez G, Erdjument-Bromage H, Yaneva M, Tempst P and Marks PA

    Cell Biology and Molecular Biology Programs, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA.

    Eighteen histone deacetylases (HDACs) are present in humans, categorized into two groups: zinc-dependent enzymes (HDAC1-11) and NAD(+)-dependent enzymes (sirtuins 1-7). Among zinc-dependent HDACs, HDAC6 is unique. It has a cytoplasmic localization, two catalytic sites, a ubiquitin-binding site, and it selectively deacetylases alpha-tubulin and Hsp90. Here, we report the discovery that the redox regulatory proteins, peroxiredoxin (Prx) I and Prx II are specific targets of HDAC6. Prx are antioxidants enzymes whose main function is H(2)O(2) reduction. Prx are elevated in many cancers and neurodegenerative diseases. The acetylated form of Prx accumulates in the absence of an active HDAC6. Acetylation of Prx increases its reducing activity, its resistance to superoxidation, and its resistance to transition to high-molecular-mass complexes. Thus, HDAC6 and Prx are targets for modulating intracellular redox status in therapeutic strategies for disorders as disparate as cancers and neurodegenerative diseases.

    Funded by: NCI NIH HHS: P30 CA008748, P30CA08748-41

    Proceedings of the National Academy of Sciences of the United States of America 2008;105;28;9633-8

  • Proteomic expression analysis of surgical human colorectal cancer tissues: up-regulation of PSB7, PRDX1, and SRP9 and hypoxic adaptation in cancer.

    Rho JH, Qin S, Wang JY and Roehrl MH

    Channing Laboratory, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02114, USA.

    Colorectal adenocarcinoma is one of the worldwide leading causes of cancer deaths. Discovery of specific biomarkers for early detection of cancer progression and the identification of underlying pathogenetic mechanisms are important tasks. Global proteomic approaches have thus far been limited by the large dynamic range of molecule concentrations in tissues and the lack of selective enrichment of the low-abundance proteome. We studied paired cancerous and normal clinical tissue specimens from patients with colorectal adenocarcinomas by heparin affinity fractionation enrichment (HAFE) followed by 2-D PAGE and tandem mass spectrometric (MS/MS) identification. Fifty-six proteins were found to be differentially expressed, of which 32 low-abundance proteins were only detectable after heparin affinity enrichment. MS/MS was used to identify 5 selected differentially expressed proteins as proteasome subunit beta type 7 (PSB7), hemoglobin alpha subunit (HBA), peroxiredoxin-1 (PRDX1), argininosuccinate synthase (ASSY), and signal recognition particle 9 kDa protein (SRP9). This is the first proteomic study detecting the differential expression of these proteins in human colorectal cancer tissue. Several of the proteins are functionally related to tissue hypoxia and hypoxic adaptation. The relative specificities of PSB7, PRDX1, and SRP9 overexpression in colon cancer were investigated by Western blot analysis of patients with colon adenocarcinomas and comparison with a control cohort of patients with lung adenocarcinomas. Furthermore, immunohistochemistry on tissue sections was used to define the specific locations of PSB7, PRDX1, and SRP9 up-regulation within heterogeneous primary human tumor tissue. Overexpression of the three proteins was restricted to the neoplastic cancer cell population within the tumors, demonstrating both cytoplasmic and nuclear localization of PSB7 and predominantly cytoplasmic localization of PRDX1 and SRP9. In summary, we describe heparin affinity fractionation enrichment (HAFE) as a prefractionation tool for the study of the human primary tissue proteome and the discovery of PSB7, PRDX1, and SRP9 up-regulation as candidate biomarkers of colon cancer.

    Funded by: NIAID NIH HHS: R01 AI057926, R01 AI057926-05, R01 AI068826, R01 AI068826-01A2; PHS HHS: R01

    Journal of proteome research 2008;7;7;2959-72

  • A novel function of peroxiredoxin 1 (Prx-1) in apoptosis signal-regulating kinase 1 (ASK1)-mediated signaling pathway.

    Kim SY, Kim TJ and Lee KY

    Department of Molecular Cell Biology, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Cheoncheon-Dong 300, Jangan-Gu, Suwon, Gyeonggi-Do 440-746, Republic of Korea.

    We report a novel function of peroxiredoxin-1 (Prx-1) in the ASK1-mediated signaling pathway. Prx-1 interacts with ASK1 via the thioredoxin-binding domain of ASK1 and this interaction is highly inducible by H2O2. However, catalytic mutants of Prx1, C52A, C173A, and C52A/C173A, could not undergo H2O2 inducible interactions, indicating that the redox-sensitive catalytic activity of Prx-1 is required for the interaction with ASK1. Prx-1 overexpression inhibited the activation of ASK1, and resulted in the inhibition of downstream signaling cascades such as the MKK3/6 and p38 pathway. In Prx-1 knockdown cells, ASK1, p38, and JNK were quickly activated, leading to apoptosis in response to H2O2. These findings suggest a negative role of Prx-1 in ASK1-induced apoptosis.

    FEBS letters 2008;582;13;1913-8

  • Up-regulation of peroxiredoxin 1 in lung cancer and its implication as a prognostic and therapeutic target.

    Kim JH, Bogner PN, Baek SH, Ramnath N, Liang P, Kim HR, Andrews C and Park YM

    Department of Cell Stress Biology, Roswell Park Cancer Institute, Buffalo, NY 14263, USA.

    Purpose: Peroxiredoxin 1 and 2 are highly homologous members of the Prx (or Prdx) protein family. Prx1 and Prx2 are elevated in several human cancers, and this seems to confer increased treatment resistance and aggressive phenotypes. This study was undertaken to examine the expression profiles of Prx1 and Prx2 in non-small cell lung cancer (NSCLC), and to test their prognostic value in predicting patient survival.

    To gain insight into the regulatory mechanisms of Prx1 and Prx2 expression in NSCLC, their respective transcript profiles were examined in NSCLC cell lines from the NCI-60 panel Affymetrix database sets, and the promoter compositions of the two genes were investigated using computer-based multiple sequence alignment analyses. Immunohistochemical analyses of Prx1 and Prx2 were done on a total of 235 NSCLC specimens with stage I through IV disease. The expression profiles of Prx1 and Prx2 in tumor specimens, and their associations with survival, were investigated.

    The levels of prx1 transcript were higher than those of prx2 in NSCLC cell lines, and the upstream regulatory sequences of the two genes display striking differences. The relative risk of death increased as Prx1 expression levels increased (P = 0.036) in a multivariate Cox model, independent of other clinicopathologic variables associated with survival. No statistically significant correlation was observed between Prx2 and survival. These results suggest that Prx1 may possess unique functions and regulatory mechanisms in NSCLC which are not shared with Prx2, and that Prx1 may serve as a new prognostic biomarker and therapeutic target in NSCLC.

    Funded by: NCI NIH HHS: CA109480, CA111846, CA126804, CA16056

    Clinical cancer research : an official journal of the American Association for Cancer Research 2008;14;8;2326-33

  • Toward a confocal subcellular atlas of the human proteome.

    Barbe L, Lundberg E, Oksvold P, Stenius A, Lewin E, Björling E, Asplund A, Pontén F, Brismar H, Uhlén M and Andersson-Svahn H

    Department of Biotechnology, AlbaNova University Center, Royal Institute of Technology, SE-106 91 Stockholm, Sweden.

    Information on protein localization on the subcellular level is important to map and characterize the proteome and to better understand cellular functions of proteins. Here we report on a pilot study of 466 proteins in three human cell lines aimed to allow large scale confocal microscopy analysis using protein-specific antibodies. Approximately 3000 high resolution images were generated, and more than 80% of the analyzed proteins could be classified in one or multiple subcellular compartment(s). The localizations of the proteins showed, in many cases, good agreement with the Gene Ontology localization prediction model. This is the first large scale antibody-based study to localize proteins into subcellular compartments using antibodies and confocal microscopy. The results suggest that this approach might be a valuable tool in conjunction with predictive models for protein localization.

    Molecular & cellular proteomics : MCP 2008;7;3;499-508

  • Human peroxiredoxin PrxI is an orthologue of yeast Tsa1, capable of suppressing genome instability in Saccharomyces cerevisiae.

    Iraqui I, Faye G, Ragu S, Masurel-Heneman A, Kolodner RD and ME

    UMR2027 Centre National de la Recherche Scientifique, Institut Curie, Centre Universitaire, Orsay, France.

    The peroxiredoxins (Prx) are conserved antioxidant proteins that use cysteine as the primary site of oxidation during the reduction of peroxides. Many organisms have more than one isoform of Prx. Deletion of TSA1, one of five Prxs in yeast Saccharomyces cerevisiae, results in accumulation of a broad spectrum of mutations including gross chromosomal rearrangements. Deletion of TSA1 is synthetically lethal with mutations in RAD6 and several key genes involved in DNA double-strand break repair. Here, we have examined the function of human PrxI and PrxII, which share a high degree of sequence identity with Tsa1, by expressing them in S. cerevisiae cells under the control of the native TSA1 promoter. We found that expression of PrxI, but not PrxII, was capable of complementing a tsa1Delta mutant for a variety of defects including genome instability, the synthetic lethality observed in rad6 Delta tsa1Delta and rad51 Delta tsa1Delta double mutants, and mutagen sensitivity. Moreover, expression of either Tsa1 or PrxI prevented Bax-induced cell death. These data indicate that PrxI is an orthologue of Tsa1. PrxI and Tsa1 seem to act on the same substrates in vivo and share similar mechanisms of function. The observation that PrxI is involved in suppressing genome instability and protecting against cell death potentially provides a better understanding of the consequences of PrxI dysfunction in human cells. The S. cerevisiae system described here could provide a sensitive tool to uncover the mechanisms that underlie the function of human Prxs.

    Funded by: NIGMS NIH HHS: GM26017, R01 GM026017, R01 GM026017-32, R37 GM026017

    Cancer research 2008;68;4;1055-63

  • Structure of the sulphiredoxin-peroxiredoxin complex reveals an essential repair embrace.

    Jönsson TJ, Johnson LC and Lowther WT

    Center for Structural Biology and Department of Biochemistry, Wake Forest University School of Medicine, Medical Center Boulevard, Winston-Salem, North Carolina 27157, USA.

    Typical 2-Cys peroxiredoxins (Prxs) have an important role in regulating hydrogen peroxide-mediated cell signalling. In this process, Prxs can become inactivated through the hyperoxidation of an active site Cys residue to Cys sulphinic acid. The unique repair of this moiety by sulphiredoxin (Srx) restores peroxidase activity and terminates the signal. The hyperoxidized form of Prx exists as a stable decameric structure with each active site buried. Therefore, it is unclear how Srx can access the sulphinic acid moiety. Here we present the 2.6 A crystal structure of the human Srx-PrxI complex. This complex reveals the complete unfolding of the carboxy terminus of Prx, and its unexpected packing onto the backside of Srx away from the Srx active site. Binding studies and activity analyses of site-directed mutants at this interface show that the interaction is required for repair to occur. Moreover, rearrangements in the Prx active site lead to a juxtaposition of the Prx Gly-Gly-Leu-Gly and Srx ATP-binding motifs, providing a structural basis for the first step of the catalytic mechanism. The results also suggest that the observed interactions may represent a common mode for other proteins to bind to Prxs.

    Funded by: NIGMS NIH HHS: R01 GM072866, R01 GM072866-03

    Nature 2008;451;7174;98-101

  • Increase in expression levels and resistance to sulfhydryl oxidation of peroxiredoxin isoforms in amyloid beta-resistant nerve cells.

    Cumming RC, Dargusch R, Fischer WH and Schubert D

    Salk Institute for Biological Studies, Cellular Neurobiology Laboratory and Peptide Biology Laboratory, La Jolla, California 92037, USA.

    Peroxiredoxins (Prxs) are a ubiquitously expressed family of thiol peroxidases that reduce hydrogen peroxide, peroxynitrite, and hydroperoxides using a highly conserved cysteine. There is substantial evidence that oxidative stress elicited by amyloid beta (Abeta) accumulation is a causative factor in the pathogenesis of Alzheimer disease (AD). Here we show that Abeta-resistant PC12 cell lines exhibit increased expression of multiple Prx isoforms with reduced cysteine oxidation. Abeta-resistant PC12 cells also display higher levels of thioredoxin and thioredoxin reductase, two enzymes critical for maintaining Prx activity. PC12 cells and rat primary hippocampal neurons transfected with wild type Prx1 exhibit increased Abeta resistance, whereas mutant Prx1, lacking a catalytic cysteine, confers no protection. Using an antibody that specifically recognizes sulfinylated and sulfonylated Prxs, it is demonstrated that primary rat cortical nerve cells exposed to Abeta display a time-dependent increase in cysteine oxidation of the catalytic site of Prxs that can be blocked by the addition of the thiol-antioxidant N-acetylcysteine. In support of previous findings, expression of Prx1 is higher in post-mortem human AD cortex tissues than in age-matched controls. In addition, two-dimensional gel electrophoresis and mass spectrometry analysis revealed that Prx2 exists in a more oxidized state in AD brains than in control brains. These findings suggest that increased Prx expression and resistance to sulfhydryl oxidation in Abeta-resistant nerve cells is a compensatory response to the oxidative stress initiated by chronic pro-oxidant Abeta exposure.

    Funded by: NIA NIH HHS: AG5142

    The Journal of biological chemistry 2007;282;42;30523-34

  • Peroxiredoxin 1 interacts with androgen receptor and enhances its transactivation.

    Park SY, Yu X, Ip C, Mohler JL, Bogner PN and Park YM

    Department of Cell Stress Biology, Roswell Park Cancer Institute, Buffalo, New York 14263, USA.

    Although hypoxia is accepted as an important microenvironmental factor influencing tumor progression and treatment response, it is usually regarded as a static global phenomenon. Consequently, less attention is given to the impact of dynamic changes in tumor oxygenation in regulating the behavior of cancer cells. Androgen receptor (AR) signaling plays a critical role in prostate cancer. We previously reported that hypoxia/reoxygenation, an in vitro condition used to mimic an unstable oxygenation climate in a tumor, stimulates AR activation. In the present study, we showed that peroxiredoxin 1 (Prx1), a member of the peroxiredoxin protein family, acts as a key mediator in this process. We found that the aggressive LN3, C4-2, and C4-2B prostate cancer cell lines derived from LNCaP possess constitutively elevated Prx1 compared with parental cells, and display greater AR activation in response to hypoxia/reoxygenation. Although the cell survival-enhancing property of Prx1 has traditionally been attributed to its antioxidant activity, the reactive oxygen species-scavenging activity of Prx1 was not essential for AR stimulation because Prx1 itself was oxidized and inactivated by hypoxia/reoxygenation. Increased AR transactivation was observed when wild-type Prx1 or mutant Prx1 (C52S) lacking antioxidant activity was introduced into LNCaP cells. Reciprocal immunoprecipitation, chromatin immunoprecipitation, and in vitro pull-down assays corroborated that Prx1 interacts with AR and enhances its transactivation. We also show that Prx1 is capable of sensitizing a ligand-stimulated AR. Based on the above information, we suggest that disrupting the interaction between Prx1 and AR may serve as a fruitful new target in the management of prostate cancer.

    Funded by: NCI NIH HHS: CA109480, CA111846, CA126804, CA16056, CA77739

    Cancer research 2007;67;19;9294-303

  • Immunohistochemical localization of 2-Cys peroxiredoxins in human ciliary body.

    Hong S, Kim CY, Lee JH and Seong GJ

    Institute of Vision Research, Department of Ophthalmology, Yonsei University College of Medicine, Seoul, Republic of Korea.

    2-Cys peroxiredoxins (PRDX) are novel antioxidant enzymes that eliminate the hydrogen peroxide in cells to protect the cellular components from reactive oxygen species. To evaluate whether 2-Cys PRDX family plays a role in human ciliary body, the expression of PRDX I, II and III on normal human ciliary body was investigated. Three normal human ciliary body tissues obtained from three donor eyeballs were examined by an immunohistochemistry using light microscopy and fluorescent microscopy with antibodies directed against the PRDX I, II and III. In the normal human ciliary body, PRDX I, II and III were immunolocalized to the non-pigmented epithelial cells and ciliary muscle fibers. It suggests that 2-Cys PRDXs may have physiological functions to protect cells in human ciliary body.

    Tissue & cell 2007;39;5;365-8

  • Tumor suppressor Prdx1 is a prognostic factor in esophageal squamous cell carcinoma patients.

    Hoshino I, Matsubara H, Akutsu Y, Nishimori T, Yoneyama Y, Murakami K, Sakata H, Matsushita K and Ochiai T

    Department of Frontier Surgery, Graduate School of Medicine, Chiba University, Chiba 260-8670, Japan.

    Peroxiredoxins (Prdxs) are a family of antioxidant enzymes that are also known as scavengers of peroxide in mammalian cells. Some reports have shown that the overexpression of Prdx1, which is one of the peroxiredoxins that is a ubiquitously expressed protein, was related to a poor prognosis in several types of human cancers. In this study, we investigated the expression levels of Prdx1 in esophageal squamous cell carcinoma by immunohistochemistry, and the correlation between the Prdx1 expression and the clinical status was elucidated. Immunohistochemical staining was performed in 114 samples which were collected from surgical esophageal cancer specimens. Cytoplasmic staining of Prdx1 was evaluated based on the following scoring criteria: Grade I, negative or weak staining; Grade II, moderate staining; and Grade III, strong staining. The percentage of patients with a Grade I expression of Prx1 was 20% (23 of 114), 44% had Grade II (50 of 114), and 36% had Grade III (41 of 114). The Prdx1 immunoreactivity showed an inverse significant correlation with T-category (P<0.0001), lymph node metastasis (P=0.048), and stage (P=0.001). In addition, the patients with tumors exhibiting a reduced Prdx1 expression had shorter overall survival (P=0.022) in comparison to the patients with tumors which had a higher Prdx1 expression. Currently, Prdx1 has been shown to act as a tumor suppressor. Our results provide strong evidence that the reduced Prdx1 expression is an important factor in esophageal squamous cancer progression and could serve as a useful prognostic marker.

    Oncology reports 2007;18;4;867-71

  • Human peroxiredoxin 1 and 2 are not duplicate proteins: the unique presence of CYS83 in Prx1 underscores the structural and functional differences between Prx1 and Prx2.

    Lee W, Choi KS, Riddell J, Ip C, Ghosh D, Park JH and Park YM

    Department of Cell Stress Biology, Roswell Park Cancer Institute, Buffalo, NY 14263, USA.

    Human peroxiredoxins 1 and 2, also known as Prx1 and Prx2, are more than 90% homologous in their amino acid sequences. Prx1 and Prx2 are elevated in various cancers and are shown to influence diverse cellular processes. Although their growth regulatory role has traditionally been attributed to the peroxidase activity, the physiological significance of this function is unclear because the proteins are highly susceptible to inactivation by H(2)O(2). A chaperone activity appears to emerge when their peroxidase activity is lost. Structural studies suggest that they may form a homodimer or doughnut-shaped homodecamer. However, little information is available whether human Prx1 and Prx2 are duplicative in structure and function. We noted that Prx1 contains a cysteine (Cys(83)) at the putative dimer-dimer interface, which is absent in Prx2. We studied the role of Cys(83) in regulating the peroxidase and chaperone activities of Prx1, because the redox status of Cys(83) might influence the oligomeric structure and consequently the functions of Prx1. We show that Prx1 is more efficient as a molecular chaperone, whereas Prx2 is better suited as a peroxidase enzyme. Substituting Cys(83) with Ser(83) (Prx1C83S) results in dramatic changes in the structural and functional characteristics of Prx1 in a direction similar to those of Prx2. Here we also report the first crystal structure of human Prx1 and the presence of the Cys(83)-Cys(83) bond at the dimer-dimer interface of decameric Prx1. These findings are consistent with the hypothesis that human Prx1 and Prx2 possess unique functions and regulatory mechanisms and that Cys(83) bestows a distinctive identity to Prx1.

    Funded by: NCI NIH HHS: CA105500, CA109480, CA111846, CA16056; NEI NIH HHS: EY09412; NIGMS NIH HHS: GM62794

    The Journal of biological chemistry 2007;282;30;22011-22

  • Nuclear and cytoplasmic peroxiredoxin-1 differentially regulate NF-kappaB activities.

    Hansen JM, Moriarty-Craige S and Jones DP

    Department of Pediatrics, Emory School of Medicine, Emory University, 2015 Uppergate Drive #350, Atlanta, GA 30322, USA. jhansen@emory.edu

    Peroxiredoxins (Prx) are widely distributed and abundant proteins, which control peroxide concentrations and related signaling mechanisms. Prx1 is found in the cytoplasm and nucleus, but little is known about compartmentalized Prx1 function during redox signaling and oxidative stress. We targeted expression vectors to increase Prx1 in nuclei (NLS-Prx1) and cytoplasm (NES-Prx1) in HeLa cells. Results showed that NES-Prx1 inhibited NF-kappaB activation and nuclear translocation. In contrast, increased NLS-Prx1 did not affect NF-kappaB nuclear translocation but increased activity of a NF-kappaB reporter. Both NLS-Prx1 and NES-Prx1 inhibited NF-kappaB p50 oxidation, suggesting that oxidation of the redox-sensitive cysteine in p50's DNA-binding domain is regulated via peroxide metabolism in both compartments. Interestingly, following treatment with H(2)O(2), nuclear thioredoxin-1 (Trx1) redox status was protected by NLS-Prx1, and cytoplasmic Trx1 was protected by NES-Prx1. Compartmental differences from increasing Prx1 show that the redox poise of cytoplasmic and nuclear thiol systems can be dynamically controlled through peroxide elimination. Such spatial resolution and protein-specific redox differences imply that the balance of peroxide generation/metabolism in microcompartments provides an important specific component of redox signaling.

    Funded by: NIEHS NIH HHS: ES011195, ES013015, R01 ES011195, R01 ES011195-05

    Free radical biology & medicine 2007;43;2;282-8

  • A genetic association analysis of cognitive ability and cognitive ageing using 325 markers for 109 genes associated with oxidative stress or cognition.

    Harris SE, Fox H, Wright AF, Hayward C, Starr JM, Whalley LJ and Deary IJ

    Department of Psychology, University of Edinburgh, Edinburgh, UK. Sarah.Harris@hgu.mrc.ac.uk <Sarah.Harris@hgu.mrc.ac.uk&gt;

    Background: Non-pathological cognitive ageing is a distressing condition affecting an increasing number of people in our 'ageing society'. Oxidative stress is hypothesised to have a major role in cellular ageing, including brain ageing.

    Results: Associations between cognitive ageing and 325 single nucleotide polymorphisms (SNPs), located in 109 genes implicated in oxidative stress and/or cognition, were examined in a unique cohort of relatively healthy older people, on whom we have cognitive ability scores at ages 11 and 79 years (LBC1921). SNPs showing a significant positive association were then genotyped in a second cohort for whom we have cognitive ability scores at the ages of 11 and 64 years (ABC1936). An intronic SNP in the APP gene (rs2830102) was significantly associated with cognitive ageing in both LBC1921 and a combined LBC1921/ABC1936 analysis (p < 0.01), but not in ABC1936 alone.

    Conclusion: This study suggests a possible role for APP in normal cognitive ageing, in addition to its role in Alzheimer's disease.

    Funded by: Medical Research Council: MRC_MC_U127561128

    BMC genetics 2007;8;43

  • Elevated peroxiredoxin 1, but not NF-E2-related factor 2, is an independent prognostic factor for disease recurrence and reduced survival in stage I non-small cell lung cancer.

    Kim JH, Bogner PN, Ramnath N, Park Y, Yu J and Park YM

    Department of Cell Stress Biology, Roswell Park Cancer Institute, State University of New York at Buffalo, Buffalo, New York, USA.

    Purpose: Lung cancer is the leading cause of cancer death with chance of survival restricted to a subset of non-small cell lung cancer (NSCLC) patients able to undergo surgical resection. However, the recurrence rate of NSCLC after surgery remains high with few prognostic indicators of clinical outcome. Peroxiredoxin1 (Prx1) is shown to be elevated in various cancers and confers an aggressive survival phenotype. We recently cloned the prx1 promoter and found that NF-E2-related factor 2 (Nrf2) is a key transcription factor for prx1 up-regulation. Previous studies suggest that Nrf2 may be constitutively activated in NSCLC. Based on the above information, we investigated whether Prx1 and/or Nrf2 levels have prognostic significance in stage I NSCLC.

    Immunohistochemical expression of Prx1 and Nrf2 was evaluated in paraffin-embedded tissues from 90 patients who underwent a curative surgical resection. Increased expression of cytosolic Prx1 (66.7%) and nuclear Nrf2 (61.8%) was observed in this series. Prx1 elevation, but not Nrf2, correlated with reduced recurrence-free survival and overall survival on univariate (P = 0.01 and P = 0.03) and multivariate (P = 0.003 and P = 0.005) analyses.

    Conclusion: This is the first study to test the prognostic significance of Prx1 and Nrf2 in human cancers. Our results show that Prx1 expression status predicts for recurrence and shorter survival in stage I NSCLC after surgery. Considering the possible role of Prx1 and Nrf2 in radioresistance/chemoresistance, it warrants future investigation to evaluate whether elevated Prx1 and/or Nrf2 levels are predictive of treatment response in advanced lung cancer and other malignancies.

    Funded by: NCI NIH HHS: CA109480, CA111846, CA16056, PC050127

    Clinical cancer research : an official journal of the American Association for Cancer Research 2007;13;13;3875-82

  • The tumor suppressor PP2A Abeta regulates the RalA GTPase.

    Sablina AA, Chen W, Arroyo JD, Corral L, Hector M, Bulmer SE, DeCaprio JA and Hahn WC

    Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA.

    The serine-threonine protein phosphatase 2A (PP2A) is a heterotrimeric enzyme family that regulates numerous signaling pathways. Biallelic mutations of the structural PP2A Abeta subunit occur in several types of human tumors; however, the functional consequences of these cancer-associated PP2A Abeta mutations in cell transformation remain undefined. Here we show that suppression of PP2A Abeta expression permits immortalized human cells to achieve a tumorigenic state. Cancer-associated Abeta mutants fail to reverse tumorigenic phenotype induced by PP2A Abeta suppression, indicating that these mutants function as null alleles. Wild-type PP2A Abeta but not cancer-derived Abeta mutants form a complex with the small GTPase RalA. PP2A Abeta-containing complexes dephosphorylate RalA at Ser183 and Ser194, inactivating RalA and abolishing its transforming function. These observations identify PP2A Abeta as a tumor suppressor gene that transforms immortalized human cells by regulating the function of RalA.

    Funded by: NCI NIH HHS: P01 CA050661, P01 CA050661-190009, P01 CA50661

    Cell 2007;129;5;969-82

  • Mutagenesis and modeling of the peroxiredoxin (Prx) complex with the NMR structure of ATP-bound human sulfiredoxin implicate aspartate 187 of Prx I as the catalytic residue in ATP hydrolysis.

    Lee DY, Park SJ, Jeong W, Sung HJ, Oho T, Wu X, Rhee SG and Gruschus JM

    Laboratory of Cell Signaling, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892-0301, USA.

    The catalytic cysteine of certain members of the peroxiredoxin (Prx) family can be hyperoxidized to cysteinesulfinic acid during reduction of peroxides. Sulfiredoxin is responsible for the ATP-dependent reduction of cysteinesulfinic acid (SO2H) of hyperoxidized Prx. Here we report the NMR solution structure of human sulfiredoxin (hSrx), both with and without bound ATP, and we model the complex of ATP-bound hSrx with Prx. Binding ATP causes only small changes in the NMR structure of hSrx, and the bound ATP conformation is quite similar to that seen for the previously reported X-ray structure of the ADP-hSrx complex. Although hSrx binds ATP, it does not catalyze hydrolysis by itself and has no catalytic acid residue typical of most ATPase and kinase family proteins. For modeling the complex, the ATP-bound hSrx was docked to hyperoxidized Prx II using EMAP of CHARMM. In the model complex, Asn186 of Prx II (Asp187 of Prx I) is in contact with the hSrx-bound ATP beta- and gamma-phosphate groups. Asp187 of Prx I was mutated to alanine and asparagine, and binding and activity of the mutants with hSrx were compared to those of the wild type. For the D187N mutant, both binding and hydrolysis and reduction activities were comparable to those of the wild type, whereas for D187A, binding was unimpaired but ATP hydrolysis and reduction did not occur. The modeling and mutagenesis analyses strongly implicate Asp187 of Prx I as the catalytic residue responsible for ATP hydrolysis in the cysteinesulfinic acid reduction of Prx by hSrx.

    Biochemistry 2006;45;51;15301-9

  • Proteomic and bioinformatic characterization of the biogenesis and function of melanosomes.

    Chi A, Valencia JC, Hu ZZ, Watabe H, Yamaguchi H, Mangini NJ, Huang H, Canfield VA, Cheng KC, Yang F, Abe R, Yamagishi S, Shabanowitz J, Hearing VJ, Wu C, Appella E and Hunt DF

    Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, USA.

    Melanin, which is responsible for virtually all visible skin, hair, and eye pigmentation in humans, is synthesized, deposited, and distributed in subcellular organelles termed melanosomes. A comprehensive determination of the protein composition of this organelle has been obstructed by the melanin present. Here, we report a novel method of removing melanin that includes in-solution digestion and immobilized metal affinity chromatography (IMAC). Together with in-gel digestion, this method has allowed us to characterize melanosome proteomes at various developmental stages by tandem mass spectrometry. Comparative profiling and functional characterization of the melanosome proteomes identified approximately 1500 proteins in melanosomes of all stages, with approximately 600 in any given stage. These proteins include 16 homologous to mouse coat color genes and many associated with human pigmentary diseases. Approximately 100 proteins shared by melanosomes from pigmented and nonpigmented melanocytes define the essential melanosome proteome. Proteins validated by confirming their intracellular localization include PEDF (pigment-epithelium derived factor) and SLC24A5 (sodium/potassium/calcium exchanger 5, NCKX5). The sharing of proteins between melanosomes and other lysosome-related organelles suggests a common evolutionary origin. This work represents a model for the study of the biogenesis of lysosome-related organelles.

    Funded by: NCRR NIH HHS: RR01744; NHGRI NIH HHS: U01-HG02712; NICHD NIH HHS: HD40179; NIGMS NIH HHS: GM 37537

    Journal of proteome research 2006;5;11;3135-44

  • Transforming growth factor-beta1 induces the non-classical secretion of peroxiredoxin-I in A549 cells.

    Chang JW, Lee SH, Lu Y and Yoo YJ

    Department of Life Science, Gwangju Institute of Science and Technology (GIST), Gwangju 500-712, Republic of Korea.

    Recent studies found that peroxiredoxin-I (Prx-I) is secreted from A549 cells although it does not contain a signal peptide and is known to be a cytosolic protein. Transforming growth factor-beta1 (TGF-beta1) treatment dramatically enhanced Prx-I secretion from A549 cells, and this effect was not inhibited by brefeldin A. Further investigation revealed that A549 cells constitutively secrete TGF-beta1. Furin, a TGF-beta1-converting enzyme, was also highly activated in A549 cells. Ectopic expression of alpha(1)-antitrypsin Portland (alpha(1)-PDX), a potent furin inhibitor, blocked both TGF-beta1 activation and Prx-I secretion. Our findings collectively suggest that non-classical secretion of Prx-I is induced by TGF-beta1, which is constitutively activated by furin in A549 cells.

    Biochemical and biophysical research communications 2006;345;1;118-23

  • The DNA sequence and biological annotation of human chromosome 1.

    Gregory SG, Barlow KF, McLay KE, Kaul R, Swarbreck D, Dunham A, Scott CE, Howe KL, Woodfine K, Spencer CC, Jones MC, Gillson C, Searle S, Zhou Y, Kokocinski F, McDonald L, Evans R, Phillips K, Atkinson A, Cooper R, Jones C, Hall RE, Andrews TD, Lloyd C, Ainscough R, Almeida JP, Ambrose KD, Anderson F, Andrew RW, Ashwell RI, Aubin K, Babbage AK, Bagguley CL, Bailey J, Beasley H, Bethel G, Bird CP, Bray-Allen S, Brown JY, Brown AJ, Buckley D, Burton J, Bye J, Carder C, Chapman JC, Clark SY, Clarke G, Clee C, Cobley V, Collier RE, Corby N, Coville GJ, Davies J, Deadman R, Dunn M, Earthrowl M, Ellington AG, Errington H, Frankish A, Frankland J, French L, Garner P, Garnett J, Gay L, Ghori MR, Gibson R, Gilby LM, Gillett W, Glithero RJ, Grafham DV, Griffiths C, Griffiths-Jones S, Grocock R, Hammond S, Harrison ES, Hart E, Haugen E, Heath PD, Holmes S, Holt K, Howden PJ, Hunt AR, Hunt SE, Hunter G, Isherwood J, James R, Johnson C, Johnson D, Joy A, Kay M, Kershaw JK, Kibukawa M, Kimberley AM, King A, Knights AJ, Lad H, Laird G, Lawlor S, Leongamornlert DA, Lloyd DM, Loveland J, Lovell J, Lush MJ, Lyne R, Martin S, Mashreghi-Mohammadi M, Matthews L, Matthews NS, McLaren S, Milne S, Mistry S, Moore MJ, Nickerson T, O'Dell CN, Oliver K, Palmeiri A, Palmer SA, Parker A, Patel D, Pearce AV, Peck AI, Pelan S, Phelps K, Phillimore BJ, Plumb R, Rajan J, Raymond C, Rouse G, Saenphimmachak C, Sehra HK, Sheridan E, Shownkeen R, Sims S, Skuce CD, Smith M, Steward C, Subramanian S, Sycamore N, Tracey A, Tromans A, Van Helmond Z, Wall M, Wallis JM, White S, Whitehead SL, Wilkinson JE, Willey DL, Williams H, Wilming L, Wray PW, Wu Z, Coulson A, Vaudin M, Sulston JE, Durbin R, Hubbard T, Wooster R, Dunham I, Carter NP, McVean G, Ross MT, Harrow J, Olson MV, Beck S, Rogers J, Bentley DR, Banerjee R, Bryant SP, Burford DC, Burrill WD, Clegg SM, Dhami P, Dovey O, Faulkner LM, Gribble SM, Langford CF, Pandian RD, Porter KM and Prigmore E

    The Wellcome Trust Sanger Institute, The Wellcome Trust Genome Campus, Hinxton, Cambridgeshire CB10 1SA, UK. sgregory@chg.duhs.duke.edu

    The reference sequence for each human chromosome provides the framework for understanding genome function, variation and evolution. Here we report the finished sequence and biological annotation of human chromosome 1. Chromosome 1 is gene-dense, with 3,141 genes and 991 pseudogenes, and many coding sequences overlap. Rearrangements and mutations of chromosome 1 are prevalent in cancer and many other diseases. Patterns of sequence variation reveal signals of recent selection in specific genes that may contribute to human fitness, and also in regions where no function is evident. Fine-scale recombination occurs in hotspots of varying intensity along the sequence, and is enriched near genes. These and other studies of human biology and disease encoded within chromosome 1 are made possible with the highly accurate annotated sequence, as part of the completed set of chromosome sequences that comprise the reference human genome.

    Funded by: Medical Research Council: G0000107; Wellcome Trust

    Nature 2006;441;7091;315-21

  • [Identification of the proteins interacting with neuroprotective peptide humanin in a yeast two-hybrid system].

    Maksimov VV, Arman IP and Tarantul VZ

    Humanine is a human neuroprotective peptide with a wide action spectrum. To analyze molecular mechanisms of humanin functioning, a search for proteins interacting with this peptide was conducted using yeast two-hybrid system. Screening of human fetal brain cDNA library identified seven proteins with different functions that specifically interacted with humanin.

    Genetika 2006;42;2;274-7

  • Phosphorylation and concomitant structural changes in human 2-Cys peroxiredoxin isotype I differentially regulate its peroxidase and molecular chaperone functions.

    Jang HH, Kim SY, Park SK, Jeon HS, Lee YM, Jung JH, Lee SY, Chae HB, Jung YJ, Lee KO, Lim CO, Chung WS, Bahk JD, Yun DJ, Cho MJ and Lee SY

    Environmental Biotechnology National Core Research Center, Gyeongsang National University, Jinju 660-701, Republic of Korea.

    The H2O2-catabolizing peroxidase activity of human peroxiredoxin I (hPrxI) was previously shown to be regulated by phosphorylation of Thr90. Here, we show that hPrxI forms multiple oligomers with distinct secondary structures. HPrxI is a dual function protein, since it can behave either as a peroxidase or as a molecular chaperone. The effects of phosphorylation of hPrxI on its protein structure and dual functions were determined using site-directed mutagenesis, in which the phosphorylation site was substituted with aspartate to mimic the phosphorylated status of the protein (T90D-hPrxI). Phosphorylation of the protein induces significant changes in its protein structure from low molecular weight (MW) protein species to high MW protein complexes as well as its dual functions. In contrast to the wild type (WT)- and T90A-hPrxI, the T90D-hPrxI exhibited a markedly reduced peroxidase activity, but showed about sixfold higher chaperone activity than WT-hPrxI.

    FEBS letters 2006;580;1;351-5

  • Peroxiredoxin I expression in tongue squamous cell carcinomas as involved in tumor recurrence.

    Yanagawa T, Omura K, Harada H, Ishii T, Uwayama J, Nakaso K, Iwasa S, Koyama Y, Onizawa K, Yusa H and Yoshida H

    Department of Oral and Maxillofacial Surgery, Institute of Clinical Medicine, Graduate School of Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan. ytony@md.tsukuba.ac.jp

    Peroxiredoxin (Prx) I is an antioxidant protein expressed in proliferating cells. We investigated Prx I as marker for tongue cancer status by correlating clinical features with Prx I expression. Samples from 132 patients with squamous cell carcinoma in the tongue were examined by immunohistochemistry with an anti-Prx I antibody. Correlations between Prx I expression and the clinical features of tumors were statistically determined using univariate and multivariate analyses. Univariate analysis showed Prx I was significantly associated with local recurrence (P=0.033). By multiple logistic regression analysis, Prx I expression was associated with local recurrence (odds ratio: 2.84; 95% confidence interval: 1.09-7.43; P=0.034) and lymph node recurrence (odds ratio: 2.86; 95% confidence interval: 1.02-8.01; P=0.046). Our results suggested that Prx I expression indicates tumors with a high potential for recurrence. Prx I may be used clinically to guide treatment for squamous cell carcinoma of the tongue.

    International journal of oral and maxillofacial surgery 2005;34;8;915-20

  • Histone deacetylase inhibitor FK228 activates tumor suppressor Prdx1 with apoptosis induction in esophageal cancer cells.

    Hoshino I, Matsubara H, Hanari N, Mori M, Nishimori T, Yoneyama Y, Akutsu Y, Sakata H, Matsushita K, Seki N and Ochiai T

    Department of Frontier Surgery (M9), Graduate School of Medicine, Chiba University, Japan.

    Purpose: The histone deacetylase inhibitor FK228 shows strong activity as a potent antitumor drug but its precise mechanism is still obscure. The purpose of this study is to reveal the effect of FK228 on gene expression in the cell and to determine the mechanism of the antitumor activity of FK228 for further clinical applications.

    Microarray analysis was applied to verify the gene expression profiles of 4,608 genes after FK228 treatment using human esophageal squamous cell cancer cell lines T.Tn and TE2. Among them, peroxiredoxin 1 (Prdx1), a member of the peroxiredoxin family of antioxidant enzymes having cell growth suppression activity, as well as p21(WAF1), were significantly activated by FK288. In addition, FK228 strongly inhibited the cell growth of T.Tn and TE2 by the induction of apoptosis. Further, chromatin immunoprecipitation analysis revealed that FK228 induced the accumulation of acetylated histones H3 and H4 in Prdx1 promoter, including the Sp1-binding site. In mouse xenograft models of T.Tn and TE2 cells, FK228 injection resulted in significant tumor regression as well as activated Prdx1 expression in tumor tissues. Prdx1 suppression by RNA interference hindered the antitumor effect of FK228.

    Conclusion: Our results indicate that the antitumor effect of FK228 in esophageal cancer cells is shown at least in part through Prdx1 activation by modulating acetylation of histones in the promoter, resulting in tumor growth inhibition with apoptosis induction.

    Clinical cancer research : an official journal of the American Association for Cancer Research 2005;11;21;7945-52

  • Towards a proteome-scale map of the human protein-protein interaction network.

    Rual JF, Venkatesan K, Hao T, Hirozane-Kishikawa T, Dricot A, Li N, Berriz GF, Gibbons FD, Dreze M, Ayivi-Guedehoussou N, Klitgord N, Simon C, Boxem M, Milstein S, Rosenberg J, Goldberg DS, Zhang LV, Wong SL, Franklin G, Li S, Albala JS, Lim J, Fraughton C, Llamosas E, Cevik S, Bex C, Lamesch P, Sikorski RS, Vandenhaute J, Zoghbi HY, Smolyar A, Bosak S, Sequerra R, Doucette-Stamm L, Cusick ME, Hill DE, Roth FP and Vidal M

    Center for Cancer Systems Biology and Department of Cancer Biology, Dana-Farber Cancer Institute, Harvard Medical School, 44 Binney Street, Boston, Massachusetts 02115, USA.

    Systematic mapping of protein-protein interactions, or 'interactome' mapping, was initiated in model organisms, starting with defined biological processes and then expanding to the scale of the proteome. Although far from complete, such maps have revealed global topological and dynamic features of interactome networks that relate to known biological properties, suggesting that a human interactome map will provide insight into development and disease mechanisms at a systems level. Here we describe an initial version of a proteome-scale map of human binary protein-protein interactions. Using a stringent, high-throughput yeast two-hybrid system, we tested pairwise interactions among the products of approximately 8,100 currently available Gateway-cloned open reading frames and detected approximately 2,800 interactions. This data set, called CCSB-HI1, has a verification rate of approximately 78% as revealed by an independent co-affinity purification assay, and correlates significantly with other biological attributes. The CCSB-HI1 data set increases by approximately 70% the set of available binary interactions within the tested space and reveals more than 300 new connections to over 100 disease-associated proteins. This work represents an important step towards a systematic and comprehensive human interactome project.

    Funded by: NCI NIH HHS: R33 CA132073; NHGRI NIH HHS: P50 HG004233, R01 HG001715, RC4 HG006066, U01 HG001715; NHLBI NIH HHS: U01 HL098166

    Nature 2005;437;7062;1173-8

  • A human protein-protein interaction network: a resource for annotating the proteome.

    Stelzl U, Worm U, Lalowski M, Haenig C, Brembeck FH, Goehler H, Stroedicke M, Zenkner M, Schoenherr A, Koeppen S, Timm J, Mintzlaff S, Abraham C, Bock N, Kietzmann S, Goedde A, Toksöz E, Droege A, Krobitsch S, Korn B, Birchmeier W, Lehrach H and Wanker EE

    Max Delbrueck Center for Molecular Medicine, 13092 Berlin-Buch, Germany.

    Protein-protein interaction maps provide a valuable framework for a better understanding of the functional organization of the proteome. To detect interacting pairs of human proteins systematically, a protein matrix of 4456 baits and 5632 preys was screened by automated yeast two-hybrid (Y2H) interaction mating. We identified 3186 mostly novel interactions among 1705 proteins, resulting in a large, highly connected network. Independent pull-down and co-immunoprecipitation assays validated the overall quality of the Y2H interactions. Using topological and GO criteria, a scoring system was developed to define 911 high-confidence interactions among 401 proteins. Furthermore, the network was searched for interactions linking uncharacterized gene products and human disease proteins to regulatory cellular pathways. Two novel Axin-1 interactions were validated experimentally, characterizing ANP32A and CRMP1 as modulators of Wnt signaling. Systematic human protein interaction screens can lead to a more comprehensive understanding of protein function and cellular processes.

    Cell 2005;122;6;957-68

  • Peroxiredoxin I and II are up-regulated during differentiation of epidermal keratinocytes.

    Yun SJ, Seo JJ, Chae JY and Lee SC

    Department of Dermatology, Chonnam National University Medical School, 8 Hak-dong, Gwangju, 501-757, Korea (South).

    Peroxiredoxins (Prxs) are expressed in the epidermis, and the accentuated expression of the Prx I and Prx II isotypes (Prx I/II) in the suprabasal layers suggests the potential role of Prx I/II in epidermal differentiation. To evaluate the novel function of Prx I/II, we checked the modulation of Prx I/II in differentiating keratinocytes. To induce differentiation in vitro, normal human epidermal keratinocytes (NHEK) were cultured for up to 10 days after the confluent state (post-confluency). In Western blot analysis, the marked induction of Prx I was observed from the second day, but the marked induction of Prx II was observed later from the sixth day of post-confluency, when loricrin and transglutaminase 1 were induced (sixth day of post-confluency). When NHEK cells were treated with INF-gamma and TGF-beta1, Prx I/II were up-regulated by INF-gamma, but Prx I/II were down-regulated by TGF-beta1. In summary, Prx I and Prx II are induced at the early and late stage of differentiation of NHEK cells, respectively.

    Archives of dermatological research 2005;296;12;555-9

  • Nucleolar proteome dynamics.

    Andersen JS, Lam YW, Leung AK, Ong SE, Lyon CE, Lamond AI and Mann M

    Department of Biochemistry and Molecular Biology, Campusvej 55, DK-5230 Odense M, Denmark.

    The nucleolus is a key organelle that coordinates the synthesis and assembly of ribosomal subunits and forms in the nucleus around the repeated ribosomal gene clusters. Because the production of ribosomes is a major metabolic activity, the function of the nucleolus is tightly linked to cell growth and proliferation, and recent data suggest that the nucleolus also plays an important role in cell-cycle regulation, senescence and stress responses. Here, using mass-spectrometry-based organellar proteomics and stable isotope labelling, we perform a quantitative analysis of the proteome of human nucleoli. In vivo fluorescent imaging techniques are directly compared to endogenous protein changes measured by proteomics. We characterize the flux of 489 endogenous nucleolar proteins in response to three different metabolic inhibitors that each affect nucleolar morphology. Proteins that are stably associated, such as RNA polymerase I subunits and small nuclear ribonucleoprotein particle complexes, exit from or accumulate in the nucleolus with similar kinetics, whereas protein components of the large and small ribosomal subunits leave the nucleolus with markedly different kinetics. The data establish a quantitative proteomic approach for the temporal characterization of protein flux through cellular organelles and demonstrate that the nucleolar proteome changes significantly over time in response to changes in cellular growth conditions.

    Funded by: Wellcome Trust: 073980

    Nature 2005;433;7021;77-83

  • Immunoaffinity profiling of tyrosine phosphorylation in cancer cells.

    Rush J, Moritz A, Lee KA, Guo A, Goss VL, Spek EJ, Zhang H, Zha XM, Polakiewicz RD and Comb MJ

    Cell Signaling Technology Inc., 166B Cummings Center, Beverly, Massachusetts 01915, USA.

    Tyrosine kinases play a prominent role in human cancer, yet the oncogenic signaling pathways driving cell proliferation and survival have been difficult to identify, in part because of the complexity of the pathways and in part because of low cellular levels of tyrosine phosphorylation. In general, global phosphoproteomic approaches reveal small numbers of peptides containing phosphotyrosine. We have developed a strategy that emphasizes the phosphotyrosine component of the phosphoproteome and identifies large numbers of tyrosine phosphorylation sites. Peptides containing phosphotyrosine are isolated directly from protease-digested cellular protein extracts with a phosphotyrosine-specific antibody and are identified by tandem mass spectrometry. Applying this approach to several cell systems, including cancer cell lines, shows it can be used to identify activated protein kinases and their phosphorylated substrates without prior knowledge of the signaling networks that are activated, a first step in profiling normal and oncogenic signaling networks.

    Funded by: NCI NIH HHS: 1R43CA101106

    Nature biotechnology 2005;23;1;94-101

  • Characterization of mammalian sulfiredoxin and its reactivation of hyperoxidized peroxiredoxin through reduction of cysteine sulfinic acid in the active site to cysteine.

    Chang TS, Jeong W, Woo HA, Lee SM, Park S and Rhee SG

    Laboratory of Cell Signaling, NHLBI, National Institutes of Health, Bethesda, Maryland 20892, USA.

    Peroxiredoxins (Prxs) are a family of peroxidases that reduce hydroperoxides. The cysteine residue in the active site of certain eukaryotic Prx enzymes undergoes reversible oxidation to sulfinic acid (Cys-SO2H) during catalysis, and sulfiredoxin (Srx) has been identified as responsible for reversal of the resulting enzyme inactivation in yeast. We have now characterized mammalian orthologs of yeast Srx with an assay based on monitoring of the reduction of sulfinic Prx by immunoblot analysis with antibodies specific for the sulfinic state. Sulfinic reduction by mammalian Srx was found to be a slow process (kcat = 0.18/min) that requires ATP hydrolysis. ATP could be efficiently replaced by GTP, dATP, or dGTP but not by CTP, UTP, dCTP, or dTTP. Both glutathione and thioredoxin are potential physiological electron donors for the Srx reaction, given that their Km values (1.8 mM and 1.2 microM, respectively) are in the range of their intracellular concentrations, and the Vmax values obtained with the two reductants were similar. Although its pKa is relatively low (approximately 7.3), the active site cysteine of Srx remained reduced even when the active site cysteine of most Prx molecules became oxidized. Finally, depletion of human Srx by RNA interference suggested that Srx is largely responsible for reduction of the Cys-SO2H of Prx in A549 human cells.

    The Journal of biological chemistry 2004;279;49;50994-1001

  • The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC).

    Gerhard DS, Wagner L, Feingold EA, Shenmen CM, Grouse LH, Schuler G, Klein SL, Old S, Rasooly R, Good P, Guyer M, Peck AM, Derge JG, Lipman D, Collins FS, Jang W, Sherry S, Feolo M, Misquitta L, Lee E, Rotmistrovsky K, Greenhut SF, Schaefer CF, Buetow K, Bonner TI, Haussler D, Kent J, Kiekhaus M, Furey T, Brent M, Prange C, Schreiber K, Shapiro N, Bhat NK, Hopkins RF, Hsie F, Driscoll T, Soares MB, Casavant TL, Scheetz TE, Brown-stein MJ, Usdin TB, Toshiyuki S, Carninci P, Piao Y, Dudekula DB, Ko MS, Kawakami K, Suzuki Y, Sugano S, Gruber CE, Smith MR, Simmons B, Moore T, Waterman R, Johnson SL, Ruan Y, Wei CL, Mathavan S, Gunaratne PH, Wu J, Garcia AM, Hulyk SW, Fuh E, Yuan Y, Sneed A, Kowis C, Hodgson A, Muzny DM, McPherson J, Gibbs RA, Fahey J, Helton E, Ketteman M, Madan A, Rodrigues S, Sanchez A, Whiting M, Madari A, Young AC, Wetherby KD, Granite SJ, Kwong PN, Brinkley CP, Pearson RL, Bouffard GG, Blakesly RW, Green ED, Dickson MC, Rodriguez AC, Grimwood J, Schmutz J, Myers RM, Butterfield YS, Griffith M, Griffith OL, Krzywinski MI, Liao N, Morin R, Morrin R, Palmquist D, Petrescu AS, Skalska U, Smailus DE, Stott JM, Schnerch A, Schein JE, Jones SJ, Holt RA, Baross A, Marra MA, Clifton S, Makowski KA, Bosak S, Malek J and MGC Project Team

    The National Institutes of Health's Mammalian Gene Collection (MGC) project was designed to generate and sequence a publicly accessible cDNA resource containing a complete open reading frame (ORF) for every human and mouse gene. The project initially used a random strategy to select clones from a large number of cDNA libraries from diverse tissues. Candidate clones were chosen based on 5'-EST sequences, and then fully sequenced to high accuracy and analyzed by algorithms developed for this project. Currently, more than 11,000 human and 10,000 mouse genes are represented in MGC by at least one clone with a full ORF. The random selection approach is now reaching a saturation point, and a transition to protocols targeted at the missing transcripts is now required to complete the mouse and human collections. Comparison of the sequence of the MGC clones to reference genome sequences reveals that most cDNA clones are of very high sequence quality, although it is likely that some cDNAs may carry missense variants as a consequence of experimental artifact, such as PCR, cloning, or reverse transcriptase errors. Recently, a rat cDNA component was added to the project, and ongoing frog (Xenopus) and zebrafish (Danio) cDNA projects were expanded to take advantage of the high-throughput MGC pipeline.

    Funded by: PHS HHS: N01-C0-12400

    Genome research 2004;14;10B;2121-7

  • Regeneration of peroxiredoxins by p53-regulated sestrins, homologs of bacterial AhpD.

    Budanov AV, Sablina AA, Feinstein E, Koonin EV and Chumakov PM

    Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH 44195, USA.

    Acting as a signal, hydrogen peroxide circumvents antioxidant defense by overoxidizing peroxiredoxins (Prxs), the enzymes that metabolize peroxides. We show that sestrins, a family of proteins whose expression is modulated by p53, are required for regeneration of Prxs containing Cys-SO(2)H, thus reestablishing the antioxidant firewall. Sestrins contain a predicted redox-active domain homologous to AhpD, the enzyme catalyzing the reduction of a bacterial Prx, AhpC. Purified Hi95 (sestrin 2) protein supports adenosine triphosphate-dependent reduction of overoxidized PrxI in vitro, indicating that unlike AhpD, which is a disulfide reductase, sestrins are cysteine sulfinyl reductases. As modulators of peroxide signaling and antioxidant defense, sestrins constitute potential therapeutic targets.

    Science (New York, N.Y.) 2004;304;5670;596-600

  • Preferential elevation of Prx I and Trx expression in lung cancer cells following hypoxia and in human lung cancer tissues.

    Kim HJ, Chae HZ, Kim YJ, Kim YH, Hwangs TS, Park EM and Park YM

    Department of Internal Medicine, Yonsei University College of Medicine, Korea.

    Transient/chronic microenvironmental hypoxia that exists within a majority of solid tumors has been suggested to have a profound influence on tumor growth and therapeutic outcome. Since the functions of novel antioxidant proteins, peroxiredoxin I (Prx I) and II, have been implicated in regulating cell proliferation, differentiation, and apoptosis, it was of our special interest to probe a possible role of Prx I and II in the context of hypoxic tumor microenvironment. Since both Prx I and II use thioredoxin (Trx) as an electron donor and Trx is a substrate for thioredoxin reductase (TrxR), we investigated the regulation of Trx and TrxR as well as Prx expression following hypoxia. Here we show a dynamic change of glutathione homeostasis in lung cancer A549 cells and an up-regulation of Prx I and Trx following hypoxia. Western blot analysis of 10 human lung cancer and paired normal lung tissues also revealed an elevated expression of Prx I and Trx proteins in lung cancer tissues. Immunohistochemical analysis of the lung cancer tissues confirmed an augmented Prx I and Trx expression in cancer cells with respect to the parenchymal cells in adjacent normal lung tissue. Based on these results, we suggest that the redox changes in lung tumor microenvironment could have acted as a trigger for the up-regulation of Prx I and Trx in lung cancer cells. Although the clinical significance of our finding awaits more rigorous future study, preferential augmentation of the Prx I and Trx in lung cancer cells may well represent an attempt of cancer cells to manipulate a dynamic redox change in tumor microenvironment in a manner that is beneficial for their proliferation and malignant progression.

    Cell biology and toxicology 2003;19;5;285-98

  • Regeneration of peroxiredoxins during recovery after oxidative stress: only some overoxidized peroxiredoxins can be reduced during recovery after oxidative stress.

    Chevallet M, Wagner E, Luche S, van Dorsselaer A, Leize-Wagner E and Rabilloud T

    Commissariat à l'Energie Atomique-Laboratoire de Bioénergétique Cellulaire et Pathologique, EA 2943, Département Réponses et Dynamique Cellulaire/BioEnergétique Cellulaire et Pathologique-Grenoble, 17 rue des martyrs, F-38054 Grenoble Cedex 9, France.

    Peroxiredoxins (prx) are redox enzymes using an activated cysteine as their active site. This activated cysteine can be easily overoxidized to cysteine sulfinic acid or cysteine sulfonic acid, especially under oxidative stress conditions. The regeneration of peroxiredoxins after a short, intense oxidative stress was studied, using a proteomics approach. Important differences in regeneration speed were found, prx2 being the fastest regenerated protein, followed by prx1, whereas prx3 and prx6 were regenerated very slowly. Further study of the mechanism of this regeneration by pulse-chase experiments using stable isotope labeling and cycloheximide demonstrated that the fast-regenerating peroxiredoxins are regenerated at least in part by a retroreduction mechanism. This demonstrates that the overoxidation can be reversible under certain conditions. The pathway of this retroreduction and the reasons explaining the various regeneration speeds of the peroxiredoxins remain to be elucidated.

    The Journal of biological chemistry 2003;278;39;37146-53

  • Reversing the inactivation of peroxiredoxins caused by cysteine sulfinic acid formation.

    Woo HA, Chae HZ, Hwang SC, Yang KS, Kang SW, Kim K and Rhee SG

    Center for Cell Signaling Research and Division of Molecular Life Sciences, Ewha Womans University, Seoul 120-750, Korea.

    The active-site cysteine of peroxiredoxins is selectively oxidized to cysteine sulfinic acid during catalysis, which leads to inactivation of peroxidase activity. This oxidation was thought to be irreversible. However, by metabolic labeling of mammalian cells with 35S, we show that the sulfinic form of peroxiredoxin I, produced during the exposure of cells to H2O2, is rapidly reduced to the catalytically active thiol form. The mammalian cells' ability to reduce protein sulfinic acid might serve as a mechanism to repair oxidatively damaged proteins or represent a new type of cyclic modification by which the function of various proteins is regulated.

    Science (New York, N.Y.) 2003;300;5619;653-6

  • Aberrant expression of peroxiredoxin subtypes in neurodegenerative disorders.

    Krapfenbauer K, Engidawork E, Cairns N, Fountoulakis M and Lubec G

    F. Hoffman-La Roche, Basel, Switzerland.

    An increasing body of evidence indicates that oxidative stress and damage play a role in the pathogenesis of a number of diseases associated with neurodegeneration, including Down syndrome (DS), Alzheimer's disease (AD) and Pick's disease (PD). Although oxidative stress is a common element in these diseases, specific clinico-pathological phenotypes have been described for each disorder. Development of these phenotypes might be linked, among others, to differences in antioxidant response. The present study is designed to investigate expression of peroxiredoxins (Prxs), the newly characterized family of highly conserved antioxidant enzymes, and other antioxidant enzymes in frontal cortex and cerebellum of DS, AD and PD patients using the technique of proteomics. Levels of Prx I, Mn superoxide dismutase (SOD2) and glutathione-S-transferase omega1 in DS, AD and PD were not significantly different from that of controls in both brain regions investigated. In contrast, Prx II was significantly increased (P<0.05) in frontal cortex of DS, AD and PD, whereas Prx III was decreased in frontal cortex of DS (P<0.01) and PD (P<0.001). Interestingly, Prx VI displayed a significant increase (P<0.05) only in PD frontal cortex. The present data indicate that differential regulation of antioxidant enzymes exist in DS, AD and PD, suggestive of the diversity as well as distinct functional roles of these proteins. Moreover, while up-regulation of Prx II appears to provide evidence for the existence of compensatory response in increased cell loss, up-regulation of Prx VI may be used to discriminate PD from AD as well as DS.

    Brain research 2003;967;1-2;152-60

  • HIV-1 antiviral activity of recombinant natural killer cell enhancing factors, NKEF-A and NKEF-B, members of the peroxiredoxin family.

    Geiben-Lynn R, Kursar M, Brown NV, Addo MM, Shau H, Lieberman J, Luster AD and Walker BD

    Partners AIDS Research Center, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02129, USA. acceleration@rcn.com

    CD8(+) T-cells are a major source for the production of non-cytolytic factors that inhibit HIV-1 replication. In order to characterize further these factors, we analyzed gene expression profiles of activated CD8(+) T-cells using a human cDNA expression array containing 588 human cDNAs. mRNA for the chemokine I-309 (CCL1), the cytokines granulocyte-macrophage colony-stimulating factor and interleukin-13, and natural killer cell enhancing factors (NKEF) -A and -B were up-regulated in bulk CD8(+) T-cells from HIV-1 seropositive individuals compared with seronegative individuals. Recombinant NKEF-A and NKEF-B inhibited HIV-1 replication when exogenously added to acutely infected T-cells at an ID(50) (dose inhibiting HIV-1 replication by 50%) of approximately 130 nm (3 microg/ml). Additionally, inhibition against dual-tropic simian immunodeficiency virus and dual-tropic simian-human immunodeficiency virus was found. T-cells transfected with NKEF-A or NKEF-B cDNA were able to inhibit 80-98% HIV-1 replication in vitro. Elevated plasma levels of both NKEF-A and NKEF-B proteins were detected in 23% of HIV-infected non-treated individuals but not in persons treated with highly active antiviral therapy or uninfected persons. These results indicate that the peroxiredoxin family members NKEF-A and NKEF-B are up-regulated in activated CD8(+) T-cells in HIV infection, and suggest that these antioxidant proteins contribute to the antiviral activity of CD8(+) T-cells.

    Funded by: NIAID NIH HHS: AI28568, AI30914, AI46999

    The Journal of biological chemistry 2003;278;3;1569-74

  • Structure, mechanism and regulation of peroxiredoxins.

    Wood ZA, Schröder E, Robin Harris J and Poole LB

    Institute of Molecular Biology, Howard Hughes Medical Institute, University of Oregon, Eugene, OR 97403, USA.

    Peroxiredoxins (Prxs) are a ubiquitous family of antioxidant enzymes that also control cytokine-induced peroxide levels which mediate signal transduction in mammalian cells. Prxs can be regulated by changes to phosphorylation, redox and possibly oligomerization states. Prxs are divided into three classes: typical 2-Cys Prxs; atypical 2-Cys Prxs; and 1-Cys Prxs. All Prxs share the same basic catalytic mechanism, in which an active-site cysteine (the peroxidatic cysteine) is oxidized to a sulfenic acid by the peroxide substrate. The recycling of the sulfenic acid back to a thiol is what distinguishes the three enzyme classes. Using crystal structures, a detailed catalytic cycle has been derived for typical 2-Cys Prxs, including a model for the redox-regulated oligomeric state proposed to control enzyme activity.

    Funded by: NIGMS NIH HHS: GM-50389, R01 GM050389

    Trends in biochemical sciences 2003;28;1;32-40

  • Pag, a putative tumor suppressor, interacts with the Myc Box II domain of c-Myc and selectively alters its biological function and target gene expression.

    Mu ZM, Yin XY and Prochownik EV

    Section of Hematology/Oncology, The Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA.

    The highly conserved Myc Box II (MBII) domain of c-Myc is critically important for transformation and transcriptional regulation. A yeast two-hybrid screen identified Pag as a MBII-interacting protein. Pag, a member of the peroxiredoxin family, has been reported previously to bind to and inhibit the cytostatic properties of the c-Abl oncoprotein. We now show that Pag promotes increased cell size and confers a proapoptotic phenotype, two hallmark features of ectopic c-Myc overexpression. Pag and c-Myc also confer resistance to oxidative stress, a previously unrecognized property of the latter protein. In contrast, Pag inhibits tumorigenesis by c-Myc-overexpressing fibroblasts and causes a broad but selective loss of c-Myc target gene regulation. Pag is therefore an MBII-interacting protein that can either mimic or enhance some of the c-Myc properties while at the same inhibiting others. These features, along with the previously identified interaction with c-Abl, provide support for the idea that Pag functions as a tumor suppressor.

    Funded by: NCI NIH HHS: CA78259; NHLBI NIH HHS: HL33741

    The Journal of biological chemistry 2002;277;45;43175-84

  • Inactivation of human peroxiredoxin I during catalysis as the result of the oxidation of the catalytic site cysteine to cysteine-sulfinic acid.

    Yang KS, Kang SW, Woo HA, Hwang SC, Chae HZ, Kim K and Rhee SG

    Laboratory of Cell Signaling, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892, USA.

    By following peroxiredoxin I (Prx I)-dependent NADPH oxidation spectrophotometrically, we observed that Prx I activity decreased gradually with time. The decay in activity was coincident with the conversion of Prx I to a more acidic species as assessed by two-dimensional gel electrophoresis. Mass spectral analysis and studies with Cys mutants determined that this shift in pI was due to selective oxidation of the catalytic site Cys(51)-SH to Cys(51)-SO(2)H. Thus, Cys(51)-SOH generated as an intermediate during catalysis appeared to undergo occasional further oxidation to Cys(51)-SO(2)H, which cannot be reversed by thioredoxin. The presence of H(2)O(2) alone was not sufficient to cause oxidation of Cys(51) to Cys(51)-SO(2)H. Rather, the presence of complete catalytic components (H(2)O(2), thioredoxin, thioredoxin reductase, and NADPH) was necessary, indicating that such hyperoxidation occurs only when Prx I is engaged in the catalytic cycle. Likewise, hyperoxidation of Cys(172)/Ser(172) mutant Prx I required not only H(2)O(2), but also a catalysis-supporting thiol (dithiothreitol). Kinetic analysis of Prx I inactivation in the presence of a low steady-state level (<1 microm) of H(2)O(2) indicated that Prx I was hyperoxidized at a rate of 0.072% per turnover at 30 degrees C. Hyperoxidation of Prx I was also detected in HeLa cells treated with H(2)O(2).

    The Journal of biological chemistry 2002;277;41;38029-36

  • A method for detection of overoxidation of cysteines: peroxiredoxins are oxidized in vivo at the active-site cysteine during oxidative stress.

    Wagner E, Luche S, Penna L, Chevallet M, Van Dorsselaer A, Leize-Wagner E and Rabilloud T

    Laboratoire de Spectrométrie de Masse Bio-Organique, UMR CNRS 7509, ECPM, 25 rue Becquerel, 67087 Strasbourg Cedex 2, France.

    Peroxiredoxins are often encountered as double spots when analysed by two-dimensional electrophoresis. The quantitative balance between these two spots depends on the physiological conditions, and is altered in favour of the acidic variant by oxidative stress for all the peroxiredoxins we could analyse. Using HeLa cells as a model system, we have further analysed the two protein isoforms represented by the two spots for each peroxiredoxin. The use of selected enzyme digestion and MS demonstrated that the acidic variant of all the peroxiredoxins analysed is irreversibly oxidized at the active-site cysteine into cysteine sulphinic or sulphonic acid. Thus, this acidic variant represents an inactivation form of the peroxiredoxins, and provides a useful marker of oxidative damage to the cells.

    The Biochemical journal 2002;366;Pt 3;777-85

  • Regulation of peroxiredoxin I activity by Cdc2-mediated phosphorylation.

    Chang TS, Jeong W, Choi SY, Yu S, Kang SW and Rhee SG

    Laboratory of Cell Signaling, NHLBI, National Institutes of Health, Bethesda, Maryland 20892, USA.

    Hydrogen peroxide is implicated as an intracellular messenger in various cellular responses such as proliferation and differentiation. Peroxiredoxin (Prx) I is a member of the peroxiredoxin family of peroxidases and contains a consensus site (Thr(90)-Pro-Lys-Lys) for phosphorylation by cyclin-dependent kinases (CDKs). This protein has now been shown to be phosphorylated specifically on Thr(90) by several CDKs, including Cdc2, in vitro. Phosphorylation of Prx I on Thr(90) reduced the peroxidase activity of this protein by 80%. The phosphorylation of Prx I in HeLa cells was monitored with the use of antibodies specific for Prx I phosphorylated on Thr(90). Immunoblot analysis with these antibodies of HeLa cells arrested at various stages of the cell cycle revealed that Prx I phosphorylation occurs in parallel with the activation of Cdc2; Prx I phosphorylation was thus marked during mitosis but virtually undetectable during interphase. Furthermore, when Cdc2 expression was reduced by RNA interference with cognate small interfering RNAs, Prx I phosphorylation was not observed in the cells synchronized in mitotic phase. The cytosolic location of Prx I likely prevents its interaction with activated CDKs until after the breakdown of the nuclear envelope during mitosis, when Cdc2 is the CDK that is most active. Phosphorylation of Prx I on Thr(90) both in vitro and in vivo was blocked by roscovitine, an inhibitor of CDKs. These results suggest that Cdc2-mediated phosphorylation and inactivation of Prx I and the resulting intracellular accumulation of H(2)O(2) might be important for progression of the cell cycle.

    The Journal of biological chemistry 2002;277;28;25370-6

  • Proteomics analysis of cellular response to oxidative stress. Evidence for in vivo overoxidation of peroxiredoxins at their active site.

    Rabilloud T, Heller M, Gasnier F, Luche S, Rey C, Aebersold R, Benahmed M, Louisot P and Lunardi J

    CEA-Laboratoire de Bioénergétique Cellulaire et Pathologique, EA UJF 2943, DRDC/BECP, CEA-Grenoble, 17 rue des martyrs, F-38054 Grenoble Cedex 9, France.

    The proteomics analysis reported here shows that a major cellular response to oxidative stress is the modification of several peroxiredoxins. An acidic form of the peroxiredoxins appeared to be systematically increased under oxidative stress conditions. Peroxiredoxins are enzymes catalyzing the destruction of peroxides. In doing so, a reactive cysteine in the peroxiredoxin active site is weakly oxidized (disulfide or sulfenic acid) by the destroyed peroxides. Cellular thiols (e.g. thioredoxin) are used to regenerate the peroxiredoxins to their active state. Tandem mass spectrometry was carried out to characterize the modified form of the protein produced in vivo by oxidative stress. The cysteine present in the active site was shown to be oxidized into cysteic acid, leading to an inactivated form of peroxiredoxin. This strongly suggested that peroxiredoxins behave as a dam upon oxidative stress, being both important peroxide-destroying enzymes and peroxide targets. Results obtained in a primary culture of Leydig cells challenged with tumor necrosis factor alpha suggested that this oxidized/native balance of peroxiredoxin 2 may play an active role in resistance or susceptibility to tumor necrosis factor alpha-induced apoptosis.

    The Journal of biological chemistry 2002;277;22;19396-401

  • Nonredundant antioxidant defense by multiple two-cysteine peroxiredoxins in human prostate cancer cells.

    Shen C and Nathan C

    Department of Microbiology & Immunology, Weill Medical College, Cornell University, New York, New York 10021, USA. cnathan@med.cornell.edu

    Background: Peroxiredoxins (Prxs) are antioxidant enzymes expressed by most free-living organisms, often in multiple isoforms. Because mammalian Prxs have not been experimentally deleted or inhibited, it is not known how much they contribute to antioxidant defense, nor whether the multiple isoforms afford redundant or additive protection.

    Expression of the four members of the 2-Cys family of human Prxs was tested in human tumor cell lines. Monospecific antibodies were developed and used to monitor the extent and specificity of inhibition of expression of each isoform in prostate cancer cells stably transfected with antisense constructs.

    Results: Seventeen tumor lines transcribed genes for all four human Prxs. Prostate cancer cells coexpressed each isoform at the protein level. Stable transfection with antisense allowed partial, selective suppression of Prx 1, 2, 3, or 4. Prostate cancer cells were rendered more sensitive to hydrogen peroxide or an organic hydroperoxide when Prx 1, 2, or 3 but not 4 was partially suppressed, bringing them into the range of sensitivity of mouse cells. The effect of partially suppressing a single Prx was comparable to that of depleting glutathione. In contrast, sensitization to adriamycin, an antitumor agent with a redox-active quinone, followed the partial suppression of Prxs 1, 2, or 4 but not 3. Individual suppression of Prxs 1-4 had no effect on sensitivity of the cells to reactive nitrogen intermediates, tumor necrosis factor (TNF), paclitaxel (Taxol), or etoposide.

    Conclusions: The 2-Cys Prxs act in a mutually nonredundant and sometimes stress-specific fashion to protect human cells from oxidant injury. The substantial resistance of human cells to hydroperoxides may result in part from the additive action of multiple Prxs.

    Molecular medicine (Cambridge, Mass.) 2002;8;2;95-102

  • Insight into hepatocellular carcinogenesis at transcriptome level by comparing gene expression profiles of hepatocellular carcinoma with those of corresponding noncancerous liver.

    Xu XR, Huang J, Xu ZG, Qian BZ, Zhu ZD, Yan Q, Cai T, Zhang X, Xiao HS, Qu J, Liu F, Huang QH, Cheng ZH, Li NG, Du JJ, Hu W, Shen KT, Lu G, Fu G, Zhong M, Xu SH, Gu WY, Huang W, Zhao XT, Hu GX, Gu JR, Chen and Han ZG

    Chinese National Human Genome Center at Shanghai, 351 Guo Shou-Jing Road, Shanghai 201203, China.

    Human hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. In this work, we report on a comprehensive characterization of gene expression profiles of hepatitis B virus-positive HCC through the generation of a large set of 5'-read expressed sequence tag (EST) clusters (11,065 in total) from HCC and noncancerous liver samples, which then were applied to a cDNA microarray system containing 12,393 genes/ESTs and to comparison with a public database. The commercial cDNA microarray, which contains 1,176 known genes related to oncogenesis, was used also for profiling gene expression. Integrated data from the above approaches identified 2,253 genes/ESTs as candidates with differential expression. A number of genes related to oncogenesis and hepatic function/differentiation were selected for further semiquantitative reverse transcriptase-PCR analysis in 29 paired HCC/noncancerous liver samples. Many genes involved in cell cycle regulation such as cyclins, cyclin-dependent kinases, and cell cycle negative regulators were deregulated in most patients with HCC. Aberrant expression of the Wnt-beta-catenin pathway and enzymes for DNA replication also could contribute to the pathogenesis of HCC. The alteration of transcription levels was noted in a large number of genes implicated in metabolism, whereas a profile change of others might represent a status of dedifferentiation of the malignant hepatocytes, both considered as potential markers of diagnostic value. Notably, the altered transcriptome profiles in HCC could be correlated to a number of chromosome regions with amplification or loss of heterozygosity, providing one of the underlying causes of the transcription anomaly of HCC.

    Proceedings of the National Academy of Sciences of the United States of America 2001;98;26;15089-94

  • Overexpression of peroxiredoxin in human breast cancer.

    Noh DY, Ahn SJ, Lee RA, Kim SW, Park IA and Chae HZ

    Department of Surgery, College of Medicine, Seoul National University, Jongno-Ku, Korea. dynoh@plaza.snu.ac.kr

    The peroxiredoxins (Prx) are a family of 25 kDa peroxidases that can reduce H2O2 using an electron from thioredoxin (Trx) or other substances. The mammalian Prx family is divided into six groups (Prx I-VI) on the basis of homology of amino acid sequences. They are located in the cytosol and play a role in the cell signaling system. Previous reports have shown that Prx II has proliferative and anti-apoptotic properties and thus may induce carcinogenic changes. We conducted this study to reveal the change in expression of Prx in human breast cancer in comparison to normal tissues. Western immunoblotting using Prx type I, II and III antibodies was undertaken on 24 human breast cancer tissues and normal counterparts. We used antibodies against purified recombinant NKEF-A/PAG, NKEF-B and MER 5 which are the Prx isoforms. Type I Prx was overexpressed in the cancer tissues of 21 patients (87.5%), type II in 18 patients (75%) and type III in 19 patients (79.2%) in relation to normal tissue. However, no significant relationship was found between Prx overexpression and clinicopathological parameters of breast cancer such as tumor size, lymphatic invasiveness, hormone receptor status or nuclear and histologic grade. In conclusion, Prx is overexpressed in breast cancer tissues to a great extent suggesting that Prx has a proliferative effect and may be related to cancer development or progression.

    Anticancer research 2001;21;3B;2085-90

  • Protein levels of human peroxiredoxin subtypes in brains of patients with Alzheimer's disease and Down syndrome.

    Kim SH, Fountoulakis M, Cairns N and Lubec G

    Department of Pediatrics, University of Vienna, Austria.

    Human peroxiredoxin (Prx) play important roles in eliminating hydrogen peroxide generated during cellular mechanisms using electrons from thioredoxin (Trx). Oxidative stress induced by reactive oxygen species (ROS) such as hydrogen peroxide has been implicated in the pathogenesis of several neurodegenerative diseases. We applied the proteomic approach to study protein levels of three subtypes of human Prx in brain regions from patients with Alzheimer's disease (AD) and Down Syndrome (DS). Protein levels of Prx-I and Prx-II were significantly increased in AD and DS. Protein levels of Prx-III, a mitochondrial protein, however, were significantly decreased. We conclude that increased protein levels of Prx-I and Prx-II could provide protection against neuronal cell death induced by hydrogen peroxide. Decreased protein levels of Prx-III could be caused by mitochondrial damage shown in AD and DS. Showing upregulated Prx protein levels provides evidence for the involvement of ROS in the pathogenesis of AD and DS.

    Journal of neural transmission. Supplementum 2001;61;223-35

  • Peroxiredoxin I expression in human thyroid tumors.

    Yanagawa T, Ishikawa T, Ishii T, Tabuchi K, Iwasa S, Bannai S, Omura K, Suzuki H and Yoshida H

    Division of Head and Neck Surgery, Chiba Cancer Center Hospital, Japan.

    Peroxiredoxin I (Prx I) is newly discovered oxidative stress inducible protein, having a thioredoxin peroxidase activity. The Prx I expression level in 107 samples out of 60 thyroid lesions, including normal thyroid, tumors and thyroiditis including Graves' disease were examined using immunoblotting. Prx I expression levels in follicular neoplasm (P = 0.00005) and thyroiditis group (P = 0.0037) were significantly higher than that of the control group, while papillary carcinoma group did not show statistical significance. Immunohistochemistry indicated that Prx I was in epithelial cells of thyroid follicles. These results suggest that Prx I is expected to be a candidate for novel tumor markers to discriminate tissue types of tumors.

    Cancer letters 1999;145;1-2;127-32

  • Homocysteine-induced endoplasmic reticulum stress and growth arrest leads to specific changes in gene expression in human vascular endothelial cells.

    Outinen PA, Sood SK, Pfeifer SI, Pamidi S, Podor TJ, Li J, Weitz JI and Austin RC

    Department of Pathology and Molecular Medicine, McMaster University and the Hamilton Civic Hospitals Research Centre, Hamilton, Ontario, Canada.

    Alterations in the cellular redox potential by homocysteine promote endothelial cell (EC) dysfunction, an early event in the progression of atherothrombotic disease. In this study, we demonstrate that homocysteine causes endoplasmic reticulum (ER) stress and growth arrest in human umbilical vein endothelial cells (HUVEC). To determine if these effects reflect specific changes in gene expression, cDNA microarrays were screened using radiolabeled cDNA probes generated from mRNA derived from HUVEC, cultured in the absence or presence of homocysteine. Good correlation was observed between expression profiles determined by this method and by Northern blotting. Consistent with its adverse effects on the ER, homocysteine alters the expression of genes sensitive to ER stress (ie, GADD45, GADD153, ATF-4, YY1). Several other genes observed to be differentially expressed by homocysteine are known to mediate cell growth and differentiation (ie, GADD45, GADD153, Id-1, cyclin D1, FRA-2), a finding that supports the observation that homocysteine causes a dose-dependent decrease in DNA synthesis in HUVEC. Additional gene profiles also show that homocysteine decreases cellular antioxidant potential (glutathione peroxidase, NKEF-B PAG, superoxide dismutase, clusterin), which could potentially enhance the cytotoxic effects of agents or conditions known to cause oxidative damage. These results successfully demonstrate the use of cDNA microarrays in identifying homocysteine-respondent genes and indicate that homocysteine-induced ER stress and growth arrest reflect specific changes in gene expression in human vascular EC.

    Blood 1999;94;3;959-67

  • Regulatory role for a novel human thioredoxin peroxidase in NF-kappaB activation.

    Jin DY, Chae HZ, Rhee SG and Jeang KT

    Laboratory of Molecular Microbiology, NIAID, National Institutes of Health, Bethesda, Maryland 20892, USA.

    Reduction-oxidation (redox) plays a critical role in NF-kappaB activation. Diverse stimuli appear to utilize reactive oxygen species (e.g. hydrogen peroxide) as common effectors for activating NF-kappaB. Antioxidants govern intracellular redox status, and many such molecules can reduce H2O2. However, functionally, it does appear that different antioxidants are variously selective for redox regulation of certain transcription factors such as NF-kappaB. For NF-kappaB, thioredoxin has been described to be a more potent antioxidant than either glutathione or N-acetylcysteine. Thioredoxin peroxidase is the immediate enzyme that links reduction of H2O2 to thioredoxin. Several putative human thioredoxin peroxidases have been identified using recursive sequence searches/alignments with yeast or prokaryotic enzymes. None has been characterized in detail for intracellular function(s). Here, we describe a new human thioredoxin peroxidase, antioxidant enzyme AOE372, identified by virtue of its protein-protein interaction with the product of a proliferation association gene, pag, which is also a thiol-specific antioxidant. In human cells, AOE372 defines a redox pathway that specifically regulates NF-kappaB activity via a modulation of IkappaB-alpha phosphorylation in the cytoplasm. We show that AOE372 activity is regulated through either homo- or heterodimerization with other thiol peroxidases, implicating subunit assortment as a mechanism for regulating antioxidant specificities. AOE372 function suggests thioredoxin peroxidase as an immediate regulator of H2O2-mediated activation of NF-kappaB.

    The Journal of biological chemistry 1997;272;49;30952-61

  • The PAG gene product, a stress-induced protein with antioxidant properties, is an Abl SH3-binding protein and a physiological inhibitor of c-Abl tyrosine kinase activity.

    Wen ST and Van Etten RA

    Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115, USA.

    Biochemical and genetic evidence suggests that the tyrosine kinase activity of c-Abl is tightly regulated in vivo by a cellular factor binding to the Src homology 3 (SH3) domain of Abl. We used the yeast two-hybrid system to identify a gene, PAG, whose protein product (Pag) interacts specifically with the Abl SH3 domain. Pag, also known as macrophage 23-kD stress protein (MSP23), is a member of a novel family of proteins with antioxidant activity implicated in the cellular response to oxidative stress and in control of cell proliferation and differentiation. In a co-expression assay, Pag associates with c-Abl in vivo and inhibits tyrosine phosphorylation induced by overexpression of c-Abl. Inhibition requires the Abl SH3 and kinase domains and is not observed with other Abl SH3-binding proteins. Expression of Pag also inhibits the in vitro kinase activity of c-Abl, but not SH3-mutated Abl or v-Abl. When transfected in NIH-3T3 cells, Pag is localized to nucleus and cytoplasm and rescues the cytostatic effect induced by c-Abl. These observations suggest Pag is a physiological inhibitor of c-Abl in vivo.

    Genes & development 1997;11;19;2456-67

  • Antioxidant function of recombinant human natural killer enhancing factor.

    Sauri H, Butterfield L, Kim A and Shau H

    Division of Surgical Oncology, UCLA School of Medicine 90095-1782.

    Natural killer enhancing factor (NKEF) is a member of a new class of highly conserved antioxidant proteins. Members of this family have been described as thiol-specific antioxidants. In this study, we show that recombinant proteins encoded by the two human NKEF genes (nkef-A and B) possess antioxidant function in the protection of protein and DNA from oxidative damage. The production of separate proteins from each of the genes encoding NKEF is an important step in the elucidation of its function.

    Funded by: NCI NIH HHS: CA 9120-19, CA9010-18

    Biochemical and biophysical research communications 1995;208;3;964-9

  • Cloning and characterization of OSF-3, a new member of the MER5 family, expressed in mouse osteoblastic cells.

    Kawai S, Takeshita S, Okazaki M, Kikuno R, Kudo A and Amann E

    Pharma Research Laboratories, Hoechst Japan Limited, Saitama.

    A cDNA library prepared from the mouse osteoblastic cell line, MC3T3-E1, was screened for the presence of specifically expressed genes by employing subtraction hybridization/differential screening methods. A cDNA clone was identified and sequenced, encoding a protein designated as osteoblast specific factor 3 (OSF-3) comprising 199 amino acids. RNA dot blot analysis indicated weak OSF-3 expression in thymus, spleen, brain, lung, testis, and heart, and high expression in kidney and liver. A homology search of an amino acid sequence database revealed a strong relationship of OSF-3 to the MER5 (gene preferentially expression in murine erythroleukemia cells) protein and human pag (proliferation associated gene) product. This indicates that OSF-3 plays an intrinsic role in the proliferation and/or differentiation of bone cells.

    Journal of biochemistry 1994;115;4;641-3

  • Identification of natural killer enhancing factor as a major antioxidant in human red blood cells.

    Shau H and Kim A

    Division of Surgical Oncology, UCLA Medical Center 90024-1782.

    Human natural killer enhancing factor genes (NKEF-A and B) share extensive homology with several genes from other organisms known to be induced by oxidative stress and to protect organisms and proteins from oxidative destruction. In this study, we have identified natural killer enhancing factor as an abundant protein in red blood cell cytosol. Highly purified natural killer enhancing factor blocks inactivation of enzymes by mixed metal-thiol oxidation. Thus, natural killer enhancing factor is a major antioxidant protecting red blood cells from oxidative injuries.

    Biochemical and biophysical research communications 1994;199;1;83-8

  • Organization and chromosomal assignment of two human PAG gene loci: PAGA encoding a functional gene and PAGB a processed pseudogene.

    Prospéri MT, Apiou F, Dutrillaux B and Goubin G

    URA 620 CNRS, Institut Curie, Paris, France.

    A cDNA, designated PAG, was recently isolated by differential cloning between an untransformed and a ras-transformed human mammary cell line. Higher levels of expression were found to be associated with cell proliferation. The absence in the pag protein of known consensus sequence, as well as its close relationship with a gene product involved in the differentiation of a mouse erythroleukemia cell line, has suggested that the PAG gene belongs to a family of genes associated with cell proliferation and differentiation. To further characterize this gene, a physical map has been established from a human genomic cosmid library. The PAG gene spans 13 kb of DNA and contains six exons. The promoter region is GC-rich and contains a TFIID motif located 25 nucleotides upstream of the potential site for initiation of transcription and potential recognition sites for a variety of trans-acting factors. Using fluorescence in situ hybridization, the PAG gene was mapped to human chromosome band 1p34.1. A pseudogene was also isolated, sequenced, and mapped to human chromosome band 9p22.

    Genomics 1994;19;2;236-41

  • Cloning and sequence analysis of candidate human natural killer-enhancing factor genes.

    Shau H, Butterfield LH, Chiu R and Kim A

    Division of Surgical Oncology, UCLA School of Medicine 90024-1782.

    A cytosol factor from human red blood cells enhances natural killer (NK) activity. This factor, termed NK-enhancing factor (NKEF), is a protein of 44,000 M(r) consisting of two subunits of equal size linked by disulfide bonds. NKEF is expressed in the NK-sensitive erythroleukemic cell line K562. Using an antibody specific for NKEF as a probe for immunoblot screening, we isolated several clones from a lambda gt11 cDNA library of K562. Additional subcloning and sequencing revealed that the candidate NKEF cDNAs fell into one of two catagories of closely related but non-identical genes, referred to as NKEF A and B. They are 88% identical in amino acid sequence and 71% identical in nucleotide sequence. Southern blot analysis suggests that there are two to three NKEF family members in the genome. Analysis of predicted amino acid sequences indicates that both NKEF A and B are cytosol proteins with several phosphorylation sites each, but that they have no glycosylation sites. They are significantly homologous to several other proteins from a wide variety of organisms ranging from prokaryotes to mammals, especially with regard to several well-conserved motifs within the amino acid sequences. The biological functions of these proteins in other species are mostly unknown, but some of them were reported to be induced by oxidative stress. Therefore, as well as for immunoregulation of NK activity, NKEF may be important for cells in coping with oxidative insults.

    Funded by: NCI NIH HHS: NCI CA-9120-19

    Immunogenetics 1994;40;2;129-34

  • A human cDNA corresponding to a gene overexpressed during cell proliferation encodes a product sharing homology with amoebic and bacterial proteins.

    Prospéri MT, Ferbus D, Karczinski I and Goubin G

    Laboratoire d'Oncogenèse, Institut Curie, Paris, France.

    A clone, designated pag, was isolated by differential screening of cDNA libraries made from the untransformed 1f40 and ras-transformed human mammary epithelial cell line HBL100. This cDNA corresponds to a gene constitutively expressed in most human cells which is induced to higher levels upon serum stimulation in untransformed and ras-transformed HBL100 cells. However, the abundance of the pag transcript is approximately 3-fold higher in transformed as compared to untransformed cells after 7-15 h of serum stimulation. In the promyelocytic leukemia cell line HL60 induced to differentiate the level of pag mRNA starts to decrease between 48 and 72 h following induction. During this period, which represents the commitment phase of differentiation, HL60 cells cease to proliferate. Therefore, in HBL100 and HL60 cells, higher levels of pag gene expression are correlated with cell proliferation. The pag cDNA codes for a 22-kDa protein, devoid of known consensus motifs, and shares 66% homology with a murine gene product (MER5) that is preferentially expressed in erythroleukemia cells during the early period of cell differentiation. In addition, the pag gene product shares approximately 50% identity with a 29-kDa surface antigen of Entamoeba histolytica and a 26-kDa antigen of Helicobacter pylori. Distant relationship was also found with other prokaryotic proteins. The pag cDNA hybridizes to multiple sequences within human and other mammalian genomes and to fewer sequences in chicken and Saccharomyces cerevisiae. Although a true relationship between eukaryotic and prokaryotic genes is difficult to establish, the conservation of pag gene sequences throughout Eukaryotae rather suggests that the pag locus belongs to a new class of genes encoding highly conserved proteins.

    The Journal of biological chemistry 1993;268;15;11050-6

Gene lists (8)

Gene List Source Species Name Description Gene count
L00000009 G2C Homo sapiens Human PSD Human orthologues of mouse PSD adapted from Collins et al (2006) 1080
L00000015 G2C Homo sapiens Human NRC Human orthologues of mouse NRC adapted from Collins et al (2006) 186
L00000016 G2C Homo sapiens Human PSP Human orthologues of mouse PSP adapted from Collins et al (2006) 1121
L00000049 G2C Homo sapiens TAP-PSD-95-CORE TAP-PSD-95 pull-down core list (ortho) 120
L00000059 G2C Homo sapiens BAYES-COLLINS-HUMAN-PSD-CONSENSUS Human cortex PSD consensus 748
L00000061 G2C Homo sapiens BAYES-COLLINS-MOUSE-PSD-CONSENSUS Mouse cortex PSD consensus (ortho) 984
L00000069 G2C Homo sapiens BAYES-COLLINS-HUMAN-PSD-FULL Human cortex biopsy PSD full list 1461
L00000071 G2C Homo sapiens BAYES-COLLINS-MOUSE-PSD-FULL Mouse cortex PSD full list (ortho) 1556
© G2C 2014. The Genes to Cognition Programme received funding from The Wellcome Trust and the EU FP7 Framework Programmes:
EUROSPIN (FP7-HEALTH-241498), SynSys (FP7-HEALTH-242167) and GENCODYS (FP7-HEALTH-241995).

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