G2Cdb::Gene report

Gene id
G00002188
Gene symbol
PRDX6 (HGNC)
Species
Homo sapiens
Description
peroxiredoxin 6
Orthologue
G00000939 (Mus musculus)

Databases (8)

Curated Gene
OTTHUMG00000034804 (Vega human gene)
Gene
ENSG00000117592 (Ensembl human gene)
9588 (Entrez Gene)
138 (G2Cdb plasticity & disease)
PRDX6 (GeneCards)
Literature
602316 (OMIM)
Marker Symbol
HGNC:16753 (HGNC)
Protein Sequence
P30041 (UniProt)

Synonyms (8)

  • 1-Cys
  • AOP2
  • KIAA0106
  • MGC46173
  • NSGPx
  • PRX
  • aiPLA2
  • p29

Literature (45)

Pubmed - other

  • Protein expression profiling of lens epithelial cells from Prdx6-depleted mice and their vulnerability to UV radiation exposure.

    Kubo E, Hasanova N, Tanaka Y, Fatma N, Takamura Y, Singh DP and Akagi Y

    Department of Ophthalmology, Faculty of Medical Science, University of Fukui, 23-3 Shimoaiduki, Matsuoka, Eiheiji, Yoshida-gun, Fukui 910-1193, Japan. kuboe@u-fukui.ac.jp

    Oxidative stress is one of the causative factors in progression and etiology of age-related cataract. Peroxiredoxin 6 (Prdx6), a savior for cells from internal or external environmental stresses, plays a role in cellular signaling by detoxifying reactive oxygen species (ROS) and thereby controlling gene regulation. Using targeted inactivation of the Prdx6 gene, we show that Prdx6-deficient lens epithelial cells (LECs) are more vulnerable to UV-triggered cell death, a major cause of skin disorders including cataractogenesis, and these cells display abnormal protein profiles. PRDX6-depleted LECs showed phenotypic changes and formed lentoid body, a characteristic of terminal cell differentiation and epithelial-mesenchymal transition. Prdx6(-/-) LECs exposed to UV-B showed higher ROS expression and were prone to apoptosis compared with wild-type LECs, underscoring a protective role for Prdx6. Comparative proteomic analysis using fluorescence-based difference gel electrophoresis along with mass spectrometry and database searching revealed a total of 13 proteins that were differentially expressed in Prdx6(-/-) cells. Six proteins were upregulated, whereas expression of seven proteins was decreased compared with Prdx6(+/+) LECs. Among the cytoskeleton-associated proteins that were highly expressed in Prdx6-deficient LECs was tropomyosin (Tm)2beta. Protein blot and real-time PCR validated dramatic increase of Tm2beta and Tm1alpha expression in these cells. Importantly, Prdx6(+/+) LECs showed a similar pattern of Tm2beta protein expression after transforming growth factor (TGF)-beta or H(2)O(2) treatment. An extrinsic supply of PRDX6 could restore Tm2beta expression, demonstrating that PRDX6 may attenuate adverse signaling in cells and thereby maintain cellular homeostasis. Exploring redox-proteomics (Prdx6(-/-)) and characterization and identification of abnormally expressed proteins and their attenuation by PRDX6 delivery should provide a basis for development of novel therapeutic interventions to postpone ROS-mediated abnormal signaling deleterious to cells or tissues.

    Funded by: NEI NIH HHS: EY-017613, R01 EY013394, R01 EY013394-01A1

    American journal of physiology. Cell physiology 2010;298;2;C342-54

  • Identification of the amino acid sequence that targets peroxiredoxin 6 to lysosome-like structures of lung epithelial cells.

    Sorokina EM, Feinstein SI, Milovanova TN and Fisher AB

    Institute for Environmental Medicine, University of Pennsylvania, One John Morgan Bldg., 3620 Hamilton Walk, Philadelphia, PA 19104, USA.

    Peroxiredoxin 6 (Prdx6), an enzyme with glutathione peroxidase and PLA2 (aiPLA2) activities, is highly expressed in respiratory epithelium, where it participates in phospholipid turnover and antioxidant defense. Prdx6 has been localized by immunocytochemistry and subcellular fractionation to acidic organelles (lung lamellar bodies and lysosomes) and cytosol. On the basis of their pH optima, we have postulated that protein subcellular localization determines the balance between the two activities of Prdx6. Using green fluorescent protein-labeled protein expression in alveolar epithelial cell lines, we showed Prdx6 localization to organellar structures resembling lamellar bodies in mouse lung epithelial (MLE-12) cells and lysosomes in A549 cells. Localization within lamellar bodies/lysosomes was in the luminal compartment. Targeting to lysosome-like organelles was abolished by the deletion of amino acids 31-40 from the Prdx6 NH2-terminal region; deletion of the COOH-terminal region had no effect. A green fluorescent protein-labeled peptide containing only amino acids 31-40 showed lysosomal targeting that was abolished by mutation of S32 or G34 within the peptide. Studies with mutated protein indicated that lipid binding was not necessary for Prdx6 targeting. This peptide sequence has no homology to known organellar targeting motifs. These studies indicate that the localization of Prdx6 in acidic organelles and consequent PLA2 activity depend on a novel 10-aa peptide located at positions 31-40 of the protein.

    Funded by: NHLBI NIH HHS: HL-19737, HL-79063, R01 HL102016

    American journal of physiology. Lung cellular and molecular physiology 2009;297;5;L871-80

  • PRDX6 attenuates oxidative stress- and TGFbeta-induced abnormalities of human trabecular meshwork cells.

    Fatma N, Kubo E, Toris CB, Stamer WD, Camras CB and Singh DP

    Department of Ophthalmology and Visual Sciences, University of Nebraska Medical Center, Omaha, NE, USA.

    Oxidative stress and TGFbeta-induced disturbance of cells and tissues are implicated in initiation and progression of pathophysiology of cells/tissues. Using primary human trabecular meshwork (TM) cells from normal and glaucomatous subjects, this study demonstrated that peroxiredoxin (PRDX) 6, an antioxidant, offsets the deleterious effects of oxidative stress on TM cells by optimizing ROS and TGFbeta levels. An analysis of glaucomatous TM cells revealed a reduced expression of PRDX6 mRNA and protein. Biochemical assays disclosed enhanced levels of ROS, as well as high levels of TGFbetas and these cells expressed elevated extracellular matrix (ECM) and Tsp1 proteins with reduced MMP2; conditions implicated in the pathophysiology of glaucoma. Non-glaucomatous TM cells exposed to TGFbetas/ROS showed similar features as in glaucomatous cells. The abnormalities induced were reversed by delivery of PRDX6. The data provide evidence that oxidative stress-induced abnormality in TM may be related to reduced PRDX6 expression and provide a foundation for antioxidant-based therapeutics for treating glaucoma.

    Funded by: NEI NIH HHS: EY-13394, EY017613, R01 EY013394, R01 EY017613

    Free radical research 2009;43;9;783-95

  • Overexpression of peroxiredoxin I and thioredoxin1 in human breast carcinoma.

    Cha MK, Suh KH and Kim IH

    Department of Biochemistry, Paichai University, Daejeon 302-735, Republic of Korea. mkcha@pcu.ac.kr

    Background: Peroxiredoxins (Prxs) are a novel group of peroxidases containing high antioxidant efficiency. The mammalian Prx family has six distinct members (Prx I-VI) in various subcellular locations, including peroxisomes and mitochondria, places where oxidative stress is most evident. The function of Prx I in particular has been implicated in regulating cell proliferation, differentiation, and apoptosis. Since thioredoxin1 (Trx1) as an electron donor is functionally associated with Prx I, we investigated levels of expression of both Prx I and Trx1.

    Methods: We investigated levels of expression of both Prx I and Trx1 in breast cancer by real-time polymerase chain reaction (RT-PCR) and Western blot.

    Results: Levels of messenger RNA (mRNA) for both Prx I and Trx1 in normal human breast tissue were very low compared to other major human tissues, whereas their levels in breast cancer exceeded that in other solid cancers (colon, kidney, liver, lung, ovary, prostate, and thyroid). Among members of the Prx family (Prx I-VI) and Trx family (Trx1, Trx2), Prx I and Trx1 were preferentially induced in breast cancer. Moreover, the expression of each was associated with progress of breast cancer and correlated with each other. Western blot analysis of different and paired breast tissues revealed consistent and preferential expression of Prx I and Trx1 protein in breast cancer tissue.

    Conclusion: Prx I and Trx1 are overexpressed in human breast carcinoma and the expression levels are associated with tumor grade. The striking induction of Prx I and Trx1 in breast cancer may enable their use as breast cancer markers.

    Journal of experimental & clinical cancer research : CR 2009;28;93

  • Binding of peroxiredoxin 6 to substrate determines differential phospholipid hydroperoxide peroxidase and phospholipase A(2) activities.

    Manevich Y, Shuvaeva T, Dodia C, Kazi A, Feinstein SI and Fisher AB

    Institute for Environmental Medicine, University of Pennsylvania, 3620 Hamilton Walk, 1 John Morgan Building, Philadelphia, PA 19104-6068, USA.

    Peroxiredoxin 6 (Prdx6) differs from other mammalian peroxiredoxins both in its ability to reduce phospholipid hydroperoxides at neutral pH and in having phospholipase A(2) (PLA(2)) activity that is maximal at acidic pH. We previously showed an active site C47 for peroxidase activity and a catalytic triad S32-H26-D140 necessary for binding of phospholipid and PLA(2) activity. This study evaluated binding of reduced and oxidized phospholipid hydroperoxide to Prdx6 at cytosolic pH. Incubation of recombinant Prdx6 with 1-palmitoyl-2-linoleoyl-sn-glycero-3-phosphocholine hydroperoxide (PLPCOOH) resulted in peroxidase activity, cys47 oxidation as detected with Prdx6-SO2(3)) antibody, and a marked shift in the Prdx6 melting temperature by circular dichroism analysis indicating that PLPCOOH is a specific substrate for Prdx6. Preferential Prdx6 binding to oxidized liposomes was detected by changes in DNS-PE or bis-Pyr fluorescence and by ultrafiltration. Site-specific mutation of S32 or H26 in Prdx6 abolished binding while D140 mutation had no effect. Treatment of A549 cells with peroxides led to lipid peroxidation and translocation of Prdx6 from the cytosol to the cell membrane. Thus, the pH specificity for the two enzymatic activities of Prdx6 can be explained by the differential binding kinetics of the protein; Prdx6 binds to reduced phospholipid at acidic pH but at cytosolic pH binds only phospholipid that is oxidized compatible with a role for Prdx6 in the repair of peroxidized cell membranes.

    Funded by: NHLBI NIH HHS: HL19737, HL79063, P01 HL019737, P01 HL019737-330001, P01 HL079063, P01 HL079063-020001

    Archives of biochemistry and biophysics 2009;485;2;139-49

  • Mitogen-activated protein kinase-mediated phosphorylation of peroxiredoxin 6 regulates its phospholipase A(2) activity.

    Wu Y, Feinstein SI, Manevich Y, Chowdhury I, Pak JH, Kazi A, Dodia C, Speicher DW and Fisher AB

    Institute for Environmental Medicine, University of Pennsylvania School of Medicine, Philadelphia, PA 19104-6068, U.S.A.

    Prdx6 (peroxiredoxin 6), a bifunctional protein with both GSH peroxidase and PLA(2) (phospholipase A(2)) [aiPLA(2) (acidic calcium-independent PLA(2))] activities, is responsible for the metabolism of lung surfactant phospholipids. We propose that the aiPLA(2) activity of the enzyme is regulated through phosphorylation. Incubation of isolated rat alveolar type II cells (AECII) with PMA, a PKC (protein kinase C) agonist, had no effect on Prdx6 expression but led to approximately 75% increase in aiPLA(2) activity that was abolished by pretreatment of cells with the MAPK (mitogen-activated protein kinase) inhibitors, SB202190 or PD98059. Prdx6 phosphorylation after incubation of AECII with PMA was demonstrated by autoradiography after immunoprecipitation with either anti-phosphothreonine o-phosphoserine antibodies. in vitro, several active isoforms of ERK (extracellular-signal-regulated kinase) and p38 phosphorylated Prdx6, resulting in an 11-fold increase in aiPLA(2) activity. The increased activity was calcium-independent and was abolished by the aiPLA(2) inhibitors, surfactant protein A and hexadecyl-3-trifluorethylglycero-sn-2-phospho-methanol (MJ33). The peroxidase activity of Prdx6 was unaffected by phosphorylation. Mass spectroscopic analysis of in vitro phosphorylated Prdx6 showed a unique phosphorylation site at Thr-177 and mutation of this residue abolished protein phosphorylation and the increase in MAPK-mediated activity. These results show that the MAPKs can mediate phosphorylation of Prdx6 at Thr-177 with a consequent marked increase in its aiPLA(2) activity.

    Funded by: NHLBI NIH HHS: HL 19737, HL 79063, P01 HL019737, P01 HL079063, R01 HL038794, R01 HL038794-20A2

    The Biochemical journal 2009;419;3;669-79

  • Proteome analysis of schizophrenia patients Wernicke's area reveals an energy metabolism dysregulation.

    Martins-de-Souza D, Gattaz WF, Schmitt A, Novello JC, Marangoni S, Turck CW and Dias-Neto E

    Laboratório de Neurociências, Instituto de Psiquiatria, Faculdade de Medicina da USP, Rua Dr, Ovídio Pires de Campos, no 785, São Paulo, SP, CEP 05403-010, Brazil. martins@mpipsykl.mpg.de

    Background: Schizophrenia is likely to be a consequence of DNA alterations that, together with environmental factors, will lead to protein expression differences and the ultimate establishment of the illness. The superior temporal gyrus is implicated in schizophrenia and executes functions such as the processing of speech, language skills and sound processing.

    Methods: We performed an individual comparative proteome analysis using two-dimensional gel electrophoresis of 9 schizophrenia and 6 healthy control patients' left posterior superior temporal gyrus (Wernicke's area - BA22p) identifying by mass spectrometry several protein expression alterations that could be related to the disease.

    Results: Our analysis revealed 11 downregulated and 14 upregulated proteins, most of them related to energy metabolism. Whereas many of the identified proteins have been previously implicated in schizophrenia, such as fructose-bisphosphate aldolase C, creatine kinase and neuron-specific enolase, new putative disease markers were also identified such as dihydrolipoyl dehydrogenase, tropomyosin 3, breast cancer metastasis-suppressor 1, heterogeneous nuclear ribonucleoproteins C1/C2 and phosphate carrier protein, mitochondrial precursor. Besides, the differential expression of peroxiredoxin 6 (PRDX6) and glial fibrillary acidic protein (GFAP) were confirmed by western blot in schizophrenia prefrontal cortex.

    Conclusion: Our data supports a dysregulation of energy metabolism in schizophrenia as well as suggests new markers that may contribute to a better understanding of this complex disease.

    BMC psychiatry 2009;9;17

  • Prefrontal cortex shotgun proteome analysis reveals altered calcium homeostasis and immune system imbalance in schizophrenia.

    Martins-de-Souza D, Gattaz WF, Schmitt A, Rewerts C, Maccarrone G, Dias-Neto E and Turck CW

    Laboratório de Neurociências, Instituto de Psiquiatria, Universidade de São Paulo, Rua. Dr. Ovidio Pires de Campos, no 785, Consolação, São Paulo, SP 05403-010, Brazil.

    Schizophrenia is a complex disease, likely to be caused by a combination of serial alterations in a number of genes and environmental factors. The dorsolateral prefrontal cortex (Brodmann's Area 46) is involved in schizophrenia and executes high-level functions such as working memory, differentiation of conflicting thoughts, determination of right and wrong concepts and attitudes, correct social behavior and personality expression. Global proteomic analysis of post-mortem dorsolateral prefrontal cortex samples from schizophrenia patients and non-schizophrenic individuals was performed using stable isotope labeling and shotgun proteomics. The analysis resulted in the identification of 1,261 proteins, 84 of which showed statistically significant differential expression, reinforcing previous data supporting the involvement of the immune system, calcium homeostasis, cytoskeleton assembly, and energy metabolism in schizophrenia. In addition a number of new potential markers were found that may contribute to the understanding of the pathogenesis of this complex disease.

    European archives of psychiatry and clinical neuroscience 2009;259;3;151-63

  • Oxidant stress stimulates expression of the human peroxiredoxin 6 gene by a transcriptional mechanism involving an antioxidant response element.

    Chowdhury I, Mo Y, Gao L, Kazi A, Fisher AB and Feinstein SI

    Institute for Environmental Medicine, University of Pennsylvania School of Medicine, 1 John Morgan Building, 3620 Hamilton Walk, Philadelphia, PA 19104-6068, USA.

    Peroxiredoxin 6 (Prdx6) is a unique antioxidant enzyme that can reduce phospholipid and other hydroperoxides. A549 cells, a human lung-derived cell line, express both Prdx6 and Nrf2, a transcription factor that binds to antioxidant-response elements (AREs) and promotes expression of antioxidant genes. Treatment of A549 cells with 500 microM H(2)O(2) increased Prdx6 mRNA levels 2.5-fold, whereas treatment with 400 microM H(2)O(2) or 200 microM tert-butylhydroquinone (t-BHQ) triggered a corresponding 2.5-fold increase in reporter gene activity in A549 cells transfected with the pSEAP2:Basic vector (BD Bioscience), containing 1524 nucleotides of the human Prdx6 promoter region. Deletion of a consensus ARE sequence present between positions 357 and 349 before the start of transcription led to a striking decrease in both basal and H(2)O(2)- or t-BHQ-induced activation in A549 cells and H(2)O(2)-induced activation in primary rat alveolar type II cells. Cotransfection with Nrf2 stimulated the Prdx6 promoter in an ARE-dependent manner, whereas it was negatively regulated by Nrf3. siRNA targeting Nrf2 down-regulated reporter gene expression, whereas siRNA targeting the Nrf2 repressor, Keap1, up-regulated it. Binding of Nrf2 to the ARE sequence in chromatin was confirmed by PCR after chromatin immunoprecipitation. These data demonstrate that the ARE within the Prdx6 promoter is a key regulator of basal transcription of the Prdx6 gene and of its inducibility under conditions of oxidative stress.

    Funded by: NHLBI NIH HHS: HL P01-75587, HL T32-07748, P01 HL019737, P01 HL019737-320001, P01 HL079063, P01 HL079063-030001

    Free radical biology & medicine 2009;46;2;146-53

  • H2O2-dependent hyperoxidation of peroxiredoxin 6 (Prdx6) plays a role in cellular toxicity via up-regulation of iPLA2 activity.

    Kim SY, Jo HY, Kim MH, Cha YY, Choi SW, Shim JH, Kim TJ and Lee KY

    Department of Molecular Cell Biology, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Suwon 440-746, Korea.

    Peroxiredoxin 6 (Prdx6) is a bifunctional enzyme with peroxidase activity and Ca2+-independent phospholipase A2 (iPLA2) activity. Here, we report that H2O2-induced cellular toxicity acts through Prdx6 hyperoxidation. Under high concentrations of H2O2 (> 100 microm), Prdx6, and 2-Cys Prdxs were hyperoxidized. Contrary to hyperoxidation of 2-Cys Prdxs, hyperoxidation of Prdx6 was irreversible in vivo. Surprisingly, H2O2-induced cell cycle arrest at the G2/M transition correlated with hyperoxidation and increased iPLA2 activity of Prdx6. This arrest was also associated with up-regulation of p53 and p21 and with down-regulation of cyclin B1. Furthermore, the H2O2-mediated increase in iPLA2 activity was dramatically abolished in a hyperoxidation mutant (C47A), an iPLA2 mutant (S32A), and a double mutant (C47A/S32A) of Prdx6, demonstrating the essential requirement of Prdx6 C47 hyperoxidation for its iPLA2 activity. Together, our results demonstrate that H2O2-mediated hyperoxidation of Prdx6 induces cell cycle arrest at the G2/M transition through up-regulation of iPLA2 activity.

    The Journal of biological chemistry 2008;283;48;33563-8

  • Peroxiredoxin 6 in human brain: molecular forms, cellular distribution and association with Alzheimer's disease pathology.

    Power JH, Asad S, Chataway TK, Chegini F, Manavis J, Temlett JA, Jensen PH, Blumbergs PC and Gai WP

    Department of Human Physiology, School of Medicine, Flinders University, Adelaide 5042, SA, Australia. john.power@flinders.edu.au

    Peroxiredoxin 6 is an antioxidant enzyme and is the 1-cys member of the peroxiredoxin family. Using two-dimensional electrophoresis and Western blotting, we have shown for the first time that, in human control and brain tissue of patient's with Alzheimer's disease (AD), this enzyme exists as three major and five minor forms with pIs from 5.3 to 6.1. Using specific cellular markers, we have shown that peroxiredoxin 6 is present in astrocytes with very low levels in neurons, but not detectable in microglia or oligodendrocytes. In control brains, there was a very low level of peroxiredoxin 6 staining in astrocytes that was confined to a "halo" around the nucleus. In AD, there were marked increases in the number and staining intensity of peroxiredoxin 6 positive astrocytes in both gray and white matter in the midfrontal cortex, cingulate, hippocampus and amygdala. Confocal microscopy using antibodies to A beta peptide, tau and peroxiredoxin 6 showed that peroxiredoxin 6 positive astrocytes are closely involved with diffuse plaques and to a lesser extent with neuritic plaques, suggesting that plaques are producing reactive oxygen species. There appeared to be little astrocytic response to tau containing neurons. Although peroxiredoxin 6 positive astrocytes were seen to make multiple contacts with tau positive neurons, there was no intraneuronal colocalization. In brain tissue of patients with AD, many blood vessels exhibited peroxiredoxin 6 staining that appeared to be due to the astrocytic foot processes. These results suggest that oxidative stress conditions exist in AD and that peroxiredoxin 6 is an important antioxidant enzyme in human brain defenses.

    Acta neuropathologica 2008;115;6;611-22

  • 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

  • Investigation of molecular factors associated with malignant transformation of oligodendroglioma by proteomic study of a single case of rapid tumor progression.

    Park CK, Kim JH, Moon MJ, Jung JH, Lim SY, Park SH, Kim JH, Kim DG, Jung HW, Cho BK and Paek SH

    Department of Neurosurgery, Seoul National University College of Medicine, Clinical Research Institute, Seoul National University Hospital, 28 Yeongeon-dong, Jongno-gu, Seoul 110-744, South Korea.

    Purpose: Frozen tumor tissues from a patient who showed rapid progression to anaplastic oligodendroglioma after near total resection of oligodendroglioma were used to examine differential expression of proteins to gain better understanding of the pathogenesis of malignant transformation.

    Methods: We have determined their protein profiles using a 2D gel electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry approach.

    Results: Among 23 differentially expressed spots, overexpression of peroxiredoxin 6 and underexpression of rho GDP dissociation inhibitor alpha were confirmed to be valid after western blot and immunocytochemical analysis of oligodendroglioma tissue.

    Conclusions: Abnormal expression of peroxiredoxin 6 and rho GDP dissociation inhibitor alpha may be associated with malignant transformation in oligodendroglioma and these proteins might be candidates of molecular predictive factors.

    Journal of cancer research and clinical oncology 2008;134;2;255-62

  • [Search for protein-protein interaction partners of peroxiredoxin 6 with the yeast two-hybrid system].

    Budanova EN and Bystrova MF

    Peroxiredoxins (Prx) are a family of nonselenium peroxidases that are involved in cell defense against oxidative stress and in redox regulation of intracellular signaling. Mammalian peroxiredoxin 6 (Prx6) belongs to the 1-Cys Prx subfamily. The protein--protein interactions of human Prx6 were studied using a yeast two-hybrid system. Hybrid plasmid pHybLex/Zeo/Prx6, which directed synthesis of a chimeric protein consisting of the DNA-binding domain (BD) of LexA and a Prx6 sequence, was used to screen a two-hybrid cDNA library Hybrid Hunter (Invitrogen). The screening identified two potential interaction partners of Prx6: the calcium-activated cysteine endopeptidase calpain and the p50RhoGAP protein of the family of Sec14-like proteins. The possibility for the interactions observed in the two-hybrid system to occur in oxidative stress in vivo is discussed.

    Genetika 2008;44;2;170-6

  • Peroxiredoxin 6 is required for blood vessel integrity in wounded skin.

    Kümin A, Schäfer M, Epp N, Bugnon P, Born-Berclaz C, Oxenius A, Klippel A, Bloch W and Werner S

    Institute of Cell Biology, Department of Biology, ETH Zurich, Honggerberg, CH-8093 Zurich, Switzerland.

    Peroxiredoxin 6 (Prdx6) is a cytoprotective enzyme with largely unknown in vivo functions. Here, we use Prdx6 knockout mice to determine its role in UV protection and wound healing. UV-mediated keratinocyte apoptosis is enhanced in Prdx6-deficient mice. Upon skin injury, we observe a severe hemorrhage in the granulation tissue of knockout animals, which correlates with the extent of oxidative stress. At the ultrastructural level endothelial cells appear highly damaged, and their rate of apoptosis is enhanced. Knock-down of Prdx6 in cultured endothelial cells also increases their susceptibility to oxidative stress, thus confirming the sensitivity of this cell type to loss of Prdx6. Wound healing studies in bone marrow chimeric mice demonstrate that Prdx6-deficient inflammatory and endothelial cells contribute to the hemorrhage phenotype. These results provide insight into the cross-talk between hematopoietic and resident cells at the wound site and the role of reactive oxygen species in this interplay.

    The Journal of cell biology 2007;179;4;747-60

  • Identification of the functional role of peroxiredoxin 6 in the progression of breast cancer.

    Chang XZ, Li DQ, Hou YF, Wu J, Lu JS, Di GH, Jin W, Ou ZL, Shen ZZ and Shao ZM

    Breast Cancer Institute, Cancer Hospital, Department of Oncology, Shanghai Medical College, Institutes of Biomedical Science, Fudan University, Shanghai, 200032, People's Republic of China.

    Introduction: The molecular mechanisms involved in breast cancer metastasis still remain unclear to date. In our previous study, differential expression of peroxiredoxin 6 was found between the highly metastatic MDA-MB-435HM cells and their parental counterparts, MDA-MB-435 cells. In this study, we investigated the effects of peroxiredoxin 6 on the proliferation and metastatic potential of human breast cancer cells and their potential mechanism.

    Methods: Expression of peroxiredoxin 6 in the highly metastatic MDA-MB-231HM cells was investigated by RT-PCR, real-time PCR and western blot. A recombinant expression plasmid of the human peroxiredoxin 6 gene was constructed and transfected into MDA-MB-231 and MDA-MB-435 cells. The effects of peroxiredoxin 6 on the proliferation and invasion of MDA-MB-231 and MDA-MB-435 cells were investigated by the Cell Counting Kit-8 method, colony-formation assay, adhesion assay, flow cytometry and invasion assay in vitro. miRNA was used to downregulate the expression of peroxiredoxin 6. Genes related to the invasion and metastasis of cancer were determined by RT-PCR, real-time PCR and western blot. The tumorigenicity and spontaneously metastatic capability regulated by peroxiredoxin 6 were determined using an orthotopic xenograft tumor model in athymic mice.

    Results: Overexpression of peroxiredoxin 6 in MDA-MB-231HM cells compared with their parental counterparts was confirmed. Upregulation of peroxiredoxin 6 enhanced the in vitro proliferation and invasion of breast cancer cells. The enhancement was associated with decreasing levels of tissue inhibitor of matrix metalloproteinase (TIMP)-2 and increasing levels of the urokinase-type plasminogen activator receptor (uPAR), Ets-1 (E26 transformation-specific-1), matrix metalloproteinase (MMP)-9 and RhoC (ras homolog gene family, member C) expression. The results were further demonstrated by RNA interference experiments in vitro. In an in vivo study, we also demonstrated that peroxiredoxin 6-transfected breast cancer cells grew much faster and had more pulmonary metastases than control cells. By contrast, peroxiredoxin 6 knockdown breast cancer cells grew more slowly and had fewer pulmonary metastases. Effects similar to those of peroxiredoxin 6 on the uPAR, Ets-1, MMP-9, RhoC and TIMP-2 expression observed in in vitro studies were found in the in vivo study.

    Conclusion: Overexpression of peroxiredoxin 6 leads to a more invasive phenotype and metastatic potential in human breast cancer, at least in part, through regulation of the levels of uPAR, Ets-1, MMP-9, RhoC and TIMP-2 expression.

    Breast cancer research : BCR 2007;9;6;R76

  • 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

  • Interaction of surfactant protein A with peroxiredoxin 6 regulates phospholipase A2 activity.

    Wu YZ, Manevich Y, Baldwin JL, Dodia C, Yu K, Feinstein SI and Fisher AB

    Institute for Environmental Medicine, University of Pennsylvania, One John Morgan Building, 3620 Hamilton Walk, Philadelphia, PA 19104-6068, USA.

    Peroxiredoxin 6 (Prdx6) is a "moonlighting" protein with both GSH peroxidase and phospholipase A(2) (PLA(2)) activities. This protein is responsible for degradation of internalized dipalmitoylphosphatidylcholine, the major phospholipid component of lung surfactant. The PLA(2) activity is inhibited by surfactant protein A (SP-A). We postulate that SP-A regulates the PLA(2) activity of Prdx6 through direct protein-protein interaction. Recombinant human Prdx6 and SP-A isolated from human alveolar proteinosis fluid were studied. Measurement of kinetic constants at pH 4.0 (maximal PLA(2) activity) showed K(m)0.35 mm and V(max) 138 nmol/min/mg of protein. SP-A inhibited PLA(2) activity non-competitively with K(i) 10 mug/ml and was Ca(2+) -independent. Activity at pH 7.4 was approximately 50% less, and inhibition by SP-A was partially dependent on Ca(2+). Interaction of SP-A and Prdx6 at pH 7.4 was shown by Prdx6-mediated inhibition of SP-A binding to agarose beads, a pull-down assay using His-tagged Prdx6 and Ni(2) -chelating beads, co-immunoprecipitation from lung epithelial cells and from a binary mixture of the two proteins, binding after treatment with a trifunctional cross-linker, and size-exclusion chromatography. Analysis by static light scattering and surface plasmon resonance showed calcium-independent SP-A binding to Prdx6 at pH 4.0 and partial Ca(2+) dependence of binding at pH 7.4. These results indicate a direct interaction between SP-A and Prdx6, which provides a mechanism for regulation of the PLA(2) activity of Prdx6 by SP-A.

    Funded by: NHLBI NIH HHS: HL 19737

    The Journal of biological chemistry 2006;281;11;7515-25

  • Proteomic analysis of SUMO4 substrates in HEK293 cells under serum starvation-induced stress.

    Guo D, Han J, Adam BL, Colburn NH, Wang MH, Dong Z, Eizirik DL, She JX and Wang CY

    Center for Biotechnology and Genomic Medicine, Medical College of Georgia, 1120 15th Street, CA4098, Augusta, GA 30912, USA.

    The substrates of SUMO4, a novel member for the SUMO gene family, were characterized in HEK293 cells cultured under serum starvation by proteomic analysis. We identified 90 SUMO4 substrates including anti-stress proteins such as antioxidant enzymes and molecular chaperones or co-chaperones. The substrates also include proteins involved in the regulation of DNA repair and synthesis, RNA processing, protein degradation, and glucose metabolism. Several SUMO4-associated transcription factors were characterized by Western blot analyses. AP-1 was selected for in vitro conjugation assays to confirm SUMO4 sumoylation of these transcription factors. Further functional analyses of the transcription factors suggested that SUMO4 sumoylation represses AP-1 and AP-2alpha transcriptional activity, but enhances GR DNA binding capacity. These results demonstrate that SUMO4 sumoylation may play an important role in the regulation of intracellular stress.

    Biochemical and biophysical research communications 2005;337;4;1308-18

  • Saitohin, which is nested in the tau locus and confers allele-specific susceptibility to several neurodegenerative diseases, interacts with peroxiredoxin 6.

    Gao L, Tse SW, Conrad C and Andreadis A

    Shriver Center at University of Massachusetts Medical School, Waltham, Massachusetts 02452, USA.

    Saitohin is a gene unique to humans and their closest relatives, the function of which is not yet known. Saitohin contains a single polymorphism (Q7R), and its Q and R alleles belong to the H1 and H2 tau haplotype, respectively. The Saitohin Q allele confers susceptibility to several neurodegenerative diseases. To get a handle on Saitohin function, we used it as a bait in a yeast two-hybrid screen. By this assay and subsequent co-immunoprecipitation and glutathione S-transferase pull-down assays, we discovered and confirmed that Saitohin interacts with peroxiredoxin 6, a unique member of that family that is bifunctional and the levels of which increase in Pick disease. The strength of the interaction appeared to be allele-specific, giving the first distinction between the two forms of Saitohin.

    Funded by: NIA NIH HHS: AG018486

    The Journal of biological chemistry 2005;280;47;39268-72

  • Oxidative stress-dependent structural and functional switching of a human 2-Cys peroxiredoxin isotype II that enhances HeLa cell resistance to H2O2-induced cell death.

    Moon JC, Hah YS, Kim WY, Jung BG, Jang HH, Lee JR, Kim SY, Lee YM, Jeon MG, Kim CW, Cho MJ and Lee SY

    Environmental Biotechnology National Core Research Center, Division of Applied Life Sciences (BK21 Program), Department of Biochemistry, College of Medicine and Institute of Health Sciences, Gyeongsang National University, Jinju 660-701, Korea.

    Although biochemical properties of 2-Cys peroxiredoxins (Prxs) have been extensively studied, their real physiological functions in higher eukaryotic cells remain obscure and certainly warrant further study. Here we demonstrated that human (h) PrxII, a cytosolic isotype of human 2-Cys Prx, has dual functions as a peroxidase and a molecular chaperone, and that these different functions are closely associated with its adoption of distinct protein structures. Upon exposure to oxidative stress, hPrxII assumes a high molecular weight complex structure that has a highly efficient chaperone function. However, the subsequent removal of stressors induces the dissociation of this protein structure into low molecular weight proteins and triggers a chaperone-to-peroxidase functional switch. The formation of a high molecular weight hPrxII complex depends on the hyperoxidation of its N-terminal peroxidatic Cys residue as well as on its C-terminal domain, which contains a "YF motif" that is exclusively found in eukaryotic 2-Cys Prxs. A C-terminally truncated hPrxII exists as low and oligomeric protein species and does not respond to oxidative stress. Moreover, this C-terminal deletion of hPrxII converted it from an oxidation-sensitive to a hyperoxidation-resistant form of peroxidase. When functioning as a chaperone, hPrxII protects HeLa cells from H(2)O(2)-induced cell death, as measured by a terminal deoxynucleotidyltransferase-mediated dUTP nick-end labeling assay and fluorescence-activated cell sorting analysis.

    The Journal of biological chemistry 2005;280;31;28775-84

  • Peroxiredoxin 6, a 1-Cys peroxiredoxin, functions in antioxidant defense and lung phospholipid metabolism.

    Manevich Y and Fisher AB

    Institute for Environmental Medicine, University of Pennsylvania Medical Center, Philadelphia, PA 19104, USA.

    Peroxiredoxin 6 (Prdx6), a bifunctional 25-kDa protein with both GSH peroxidase and phospholipase A2 activities, is the only mammalian 1-Cys member of the peroxiredoxin superfamily and is expressed in all major organs, with a particularly high level in lung. Prdx6 uses GSH as an electron donor to reduce H2O2 and other hydroperoxides including phospholipid hydroperoxides at approximately 5 micromol/mg protein/min with K1 approximately 3 x 10(6) M(-1) s(-1). Oxidation of the Cys47 to a sulfenic acid during catalysis requires piGST-catalyzed glutathionylation and reduction with GSH to complete the enzymatic cycle. Prdx6 stably overexpressed in cells protected against oxidative stress, whereas antisense treatment resulted in oxidant stress and apoptosis. Adenoviral-mediated overexpression of Prdx6 in mouse lungs protected against the toxicity of hyperoxia, whereas Prdx6-null mice were more sensitive to the effects of hyperoxia or paraquat. We postulate that Prdx6 functions in antioxidant defense mainly by facilitating repair of damaged cell membranes via reduction of peroxidized phospholipids. The PLA2 activity of Prdx6 is Ca2+ independent and maximal at acidic pH. Inhibition of PLA2 activity results in alterations of lung surfactant phospholipid synthesis and turnover. Thus, Prdx6, a unique mammalian peroxiredoxin, is an important antioxidant enzyme and has a major role in lung phospholipid metabolism.

    Funded by: NHLBI NIH HHS: HL19737, HL65543

    Free radical biology & medicine 2005;38;11;1422-32

  • Automated yeast two-hybrid screening for nuclear receptor-interacting proteins.

    Albers M, Kranz H, Kober I, Kaiser C, Klink M, Suckow J, Kern R and Koegl M

    PheneX Pharmaceuticals AG, Im Neuenheimer Feld 515, 69120 Heidelberg, Germany.

    High throughput analysis of protein-protein interactions is an important sector of hypothesis-generating research. Using an improved and automated version of the yeast two-hybrid system, we completed a large interaction screening project with a focus on nuclear receptors and their cofactors. A total of 425 independent yeast two-hybrid cDNA library screens resulted in 6425 potential interacting protein fragments involved in 1613 different interaction pairs. We show that simple statistical parameters can be used to narrow down the data set to a high confidence set of 377 interaction pairs where validated interactions are enriched to 61% of all pairs. Within the high confidence set, there are 64 novel proteins potentially binding to nuclear receptors or their cofactors. We discuss several examples of high interest, and we expect that communication of this huge data set will help to complement our knowledge of the protein interaction repertoire of this family of transcription factors and instigate the characterization of the various novel candidate interactors.

    Molecular & cellular proteomics : MCP 2005;4;2;205-13

  • 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

  • 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

  • Polyol pathway-dependent osmotic and oxidative stresses in aldose reductase-mediated apoptosis in human lens epithelial cells: role of AOP2.

    Kubo E, Urakami T, Fatma N, Akagi Y and Singh DP

    Department of Ophthalmology, Fukui Medical University, Fukui, Japan.

    Aldose reductase (AR) has been implicated as a major contributor to the pathogenesis of diabetic cataracts. AR activation generates osmotic and oxidative stresses via the polyol pathway and induces cell death signals. Antioxidant protein 2 (AOP2) protects cells from oxidative stress. We investigated the effect of AR overexpression on polyol accumulation and on hyperglycemic oxidative stress and osmotic stress, as well as the effects of these stresses on human lens epithelial cell (hLEC) survival. hLECs overexpressing the AR became apoptotic during hyperglycemia and showed elevated levels of intracellular polyols. Glutathione and AOP2 levels were significantly decreased in these cells. Interestingly, supply of AOP2 and/or the AR inhibitor fidarestat protected the cells against hyperglycemia-induced death. Overexpression of AR increased osmotic and oxidative stresses, resulting in increased apoptosis in hLECs. Because AOP2 protects hyperglycemia-induced hLEC apoptosis, this molecule may have the potential to prevent hyperglycemia-mediated complications in diabetes.

    Funded by: NEI NIH HHS: EY13394

    Biochemical and biophysical research communications 2004;314;4;1050-6

  • Exploring proteomes and analyzing protein processing by mass spectrometric identification of sorted N-terminal peptides.

    Gevaert K, Goethals M, Martens L, Van Damme J, Staes A, Thomas GR and Vandekerckhove J

    Department of Medical Protein Research, Flanders Interuniversity Institute for Biotechnology, Ghent University, A. Baertsoenkaai 3, B-9000 Ghent, Belgium. kris.gevaert@rug.ac.be

    Current non-gel techniques for analyzing proteomes rely heavily on mass spectrometric analysis of enzymatically digested protein mixtures. Prior to analysis, a highly complex peptide mixture is either separated on a multidimensional chromatographic system or it is first reduced in complexity by isolating sets of representative peptides. Recently, we developed a peptide isolation procedure based on diagonal electrophoresis and diagonal chromatography. We call it combined fractional diagonal chromatography (COFRADIC). In previous experiments, we used COFRADIC to identify more than 800 Escherichia coli proteins by tandem mass spectrometric (MS/MS) analysis of isolated methionine-containing peptides. Here, we describe a diagonal method to isolate N-terminal peptides. This reduces the complexity of the peptide sample, because each protein has one N terminus and is thus represented by only one peptide. In this new procedure, free amino groups in proteins are first blocked by acetylation and then digested with trypsin. After reverse-phase (RP) chromatographic fractionation of the generated peptide mixture, internal peptides are blocked using 2,4,6-trinitrobenzenesulfonic acid (TNBS); they display a strong hydrophobic shift and therefore segregate from the unaltered N-terminal peptides during a second identical separation step. N-terminal peptides can thereby be specifically collected for further liquid chromatography (LC)-MS/MS analysis. Omitting the acetylation step results in the isolation of non-lysine-containing N-terminal peptides from in vivo blocked proteins.

    Nature biotechnology 2003;21;5;566-9

  • 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

  • A 29-kDa protein associated with p67phox expresses both peroxiredoxin and phospholipase A2 activity and enhances superoxide anion production by a cell-free system of NADPH oxidase activity.

    Leavey PJ, Gonzalez-Aller C, Thurman G, Kleinberg M, Rinckel L, Ambruso DW, Freeman S, Kuypers FA and Ambruso DR

    Bonfils Blood Center, Denver, Colorado 80230, USA.

    Production of toxic oxygen metabolites provides a mechanism for microbicidal activity of the neutrophil. The NADPH oxidase enzyme system initiates the production of oxygen metabolites by reducing oxygen to form superoxide anion (O(2)()). With stimulation of the respiratory burst, cytosolic oxidase components, p47(phox), p67(phox), and Rac, translocate to the phagolysomal and plasma membranes where they form a complex with cytochrome b(558) and express enzyme activity. A 29-kDa neutrophil protein (p29) was identified by co-immunoprecipitation with p67(phox). N-terminal sequence analysis of p29 revealed homology to an open reading frame gene described in a myeloid leukemia cell line. A cDNA for p29 identical to the open reading frame protein was amplified from RNA of neutrophils. Significant interaction between p29 and p67(phox) was demonstrated using a yeast two-hybrid system. A recombinant (rh) p29 was expressed in Sf9 cells resulting in a protein with an apparent molecular weight of 34,000. The rh-p29 showed immunoreactivity with the original rabbit antiserum that detected p47(phox) and p67(phox). In addition, rh-p29 exhibited PLA(2) activity, which was Ca(2+) independent, optimal at low pH, and preferential for phosphatidylcholine substrates. The recombinant protein protected glutathione synthetase and directly inactivated H(2)O(2). By activity and sequence homology, rh-p29 can be classified as a peroxiredoxin. Finally, O(2)() production by plasma membrane and recombinant cytosolic oxidase components in the SDS-activated, cell-free NADPH oxidase system were enhanced by rh-p29. This effect was not inhibited by PLA(2) inhibitors. Thus, p29 is a novel protein that associates with p67 and has peroxiredoxin activity. This protein has a potential role in protecting the NADPH oxidase by inactivating H(2)O(2) or altering signaling pathways affected by H(2)O(2).

    Funded by: NCI NIH HHS: P30-CA46954; NHLBI NIH HHS: HL20985, HL66355

    The Journal of biological chemistry 2002;277;47;45181-7

  • 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

  • 1-Cys peroxiredoxin overexpression protects cells against phospholipid peroxidation-mediated membrane damage.

    Manevich Y, Sweitzer T, Pak JH, Feinstein SI, Muzykantov V and Fisher AB

    Institute for Environmental Medicine, University of Pennsylvania Medical Center, Philadelphia, PA 19104, USA.

    1-Cys peroxiredoxin (1-cysPrx) is a novel antioxidant enzyme able to reduce phospholipid hydroperoxides in vitro by using glutathione as a reductant. This enzyme is widely expressed and is enriched in lungs. A fusion protein of green fluorescent protein with 1-cysPrx was stably expressed in a lung-derived cell line (NCI-H441) lacking endogenous enzyme. Overexpressing cells (C17 or C48) degraded H(2)O(2) and t-butylhydroperoxide more rapidly and showed decreased sensitivity to oxidant stress as measured by (51)Cr release. On exposure to (*)OH generated by Cu(2+)-ascorbate (Asc), overexpressing cells compared with H441 showed less increase in thiobarbituric acid-reactive substance and phosphatidylcholine hydroperoxide content. This effect was reversed by depletion of cellular glutathione. Diphenyl-1-pyrenoylphosphonium fluorescence, used as a real-time probe of membrane phospholipid peroxidation, increased immediately on exposure to Cu(2+)-Asc and was abolished by preincubation of cells with Trolox (a soluble vitamin E) or Tempol (a radical scavenger). The rate of diphenyl-1-pyrenoylphosphonium fluorescence increase with Cu(2+)-Asc exposure was markedly attenuated in C17 and C48 cells as compared with H441. Annexin V-Cy3 was used to detect phosphatidylserine translocation from the inner to outer leaflet of the plasma membrane. Cu(2+)-Asc treatment induced phosphatidylserine translocation within 2 h in H441 cells but none was observed in C48 cells up to 24 h. These results indicate that 1-cysPrx can scavenge peroxides but in addition can reduce peroxidized membrane phospholipids. Thus, the enzyme can protect cells against oxidant-induced plasma membrane damage, thereby playing an important role in cellular defense against oxidant stress.

    Funded by: NHLBI NIH HHS: HL07748, HL64553, T32 HL007748

    Proceedings of the National Academy of Sciences of the United States of America 2002;99;18;11599-604

  • Transcriptional regulation of the antioxidant protein 2 gene, a thiol-specific antioxidant, by lens epithelium-derived growth factor to protect cells from oxidative stress.

    Fatma N, Singh DP, Shinohara T and Chylack LT

    Center for Ophthalmic Research, Department of Surgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA.

    Antioxidant protein 2 (AOP2), a member of the newly defined family of thiol-specific antioxidant proteins, has been shown to remove H(2)O(2) and protect proteins and DNA from oxidative stress. Here we report that LEDGF is one of the regulatory factors for the AOP2 gene. We found that LEDGF bound to the heat shock element and to stress-related elements in the AOP2 promoter. It trans-activated expression of AOP2-CAT in COS-7 cells and lens epithelial cells overexpressing LEDGF. Mutations in the heat shock element and stress-related elements of the AOP2 promoter reduced LEDGF-dependent trans-activation. Lens epithelial cells showed a higher level of AOP2 mRNA in the presence of LEDGF. Cells overexpressing LEDGF exhibited a higher level of AOP2 protein, the level of which was directly related to the increase in cellular protection. Thus, LEDGF, by activating the AOP2 gene, protected and enhanced the survival of cells under oxidative stress.

    The Journal of biological chemistry 2001;276;52;48899-907

  • 1-Cys peroxiredoxin, a bifunctional enzyme with glutathione peroxidase and phospholipase A2 activities.

    Chen JW, Dodia C, Feinstein SI, Jain MK and Fisher AB

    Institute for Environmental Medicine, University of Pennsylvania Medical Center, Philadelphia, Pennsylvania 19104, USA.

    This report provides definitive evidence that the protein 1-Cys peroxiredoxin is a bifunctional ("moonlighting") enzyme with two distinct active sites. We have previously shown that human, rat, and bovine lungs contain an acidic Ca(2+)-independent phospholipase A(2) (aiPLA(2)). The cDNA encoding aiPLA(2) was found to be identical to that of a non-selenium glutathione peroxidase (NSGPx). Protein expressed using a previously reported E. coli construct which has a His-tag and 50 additional amino acids at the NH(2) terminus, did not exhibit aiPLA(2) activity. A new construct which contains the His-tag plus two extra amino acids at the COOH terminus when expressed in Escherichia coli generated a protein that hydrolyzed the sn-2 acyl chain of phospholipids at pH 4, and exhibited NSGPx activity with H(2)O(2) at pH 8. The expressed 1-Cys peroxiredoxin has identical functional properties to the native lung enzyme: aiPLA(2) activity is inhibited by the serine protease inhibitor, diethyl p-nitrophenyl phosphate, by the tetrahedral mimic 1-hexadecyl-3-trifluoroethylglycero-sn-2-phosphomethanol (MJ33), and by 1-Cys peroxiredoxin monoclonal antibody (mAb) 8H11 but these agents have no effect on NSGPx activity; NSGPx activity is inhibited by mercaptosuccinate and by 1-Cys peroxiredoxin mAb 8B3 antibody which have no effect on aiPLA(2) activity. Mutation of Ser(32) to Ala abolishes aiPLA(2) activity, yet the NSGPx activity remains unaffected; a Cys(47) to Ser mutant is devoid of peroxidase activity but aiPLA(2) activity remains intact. These results suggest that Ser(32) in the GDSWG consensus sequence provides the catalytic nucleophile for the hydrolase activity of aiPLA(2), while Cys(47) in the PVCTTE consensus sequence is at the active site for peroxidase activity. The bifunctional catalytic properties of 1-Cys peroxiredoxin are compatible with a simultaneous role for the protein in the regulation of phospholipid turnover as well as in protection against oxidative injury.

    Funded by: NHLBI NIH HHS: HL19737

    The Journal of biological chemistry 2000;275;37;28421-7

  • AOP2 (antioxidant protein 2): structure and function of a unique thiol-specific antioxidant.

    Phelan SA

    Department of Biology, Fairfield University, CT 06430, USA. sphelan@Fair1.Fairfield.edu

    The accumulation of reactive oxygen species (ROS) in response to extracellular signals or intracellular biochemical processes can be regulated by the coordinate action of many antioxidant proteins. Because moderate levels of ROS can act as intracellular messengers in many of these processes, this modulation is critical for the transduction of specific signals. The thiol-specific antioxidant (TSA) family is a highly conserved group of enzymes that can reduce hydroperoxides in the presence of a thiol-containing electron donor. AOP2 (antioxidant protein 2) is a newly described member that shows significant evolutionary conservation between many different organisms. The protein contains three motifs that are highly conserved within the TSA family, including a cysteine residue that is the active site of oxidation for this class of proteins. Although AOP2 possesses TSA activity, it has several unique characteristics, including the absence of a second cysteine residue that is conserved in all other TSA proteins, the presence of a unique carboxy-terminal domain, and a demonstrated phospholipase activity. Furthermore, AOP2 shows conservation of several amino acids important in dimer formation and active site configuration that are not found in the other family members. Together, these data strongly suggest that AOP2 is a novel thiol-dependent antioxidant that functions to scavenge particular hydroperoxides in the cell and mediate specific signals. There is also evidence supporting a role for AOP2 in certain disease processes including atherosclerosis. Further evaluation of this protein and its substrate specificity will likely shed light on its precise role in cellular oxidant defense, signal transduction and pathogenesis.

    Funded by: NHLBI NIH HHS: 1-F32-HL10124-01

    Antioxidants & redox signaling 1999;1;4;571-84

  • Crystal structure of a novel human peroxidase enzyme at 2.0 A resolution.

    Choi HJ, Kang SW, Yang CH, Rhee SG and Ryu SE

    Division of Protein Engineering, Korea Research Institute of Bioscience and Biotechnology, KIST, Yusong, Taejon, South Korea.

    Hydrogen peroxide (H2O2) has been implicated recently as an intracellular messenger that affects cellular processes including protein phosphorylation, transcription and apoptosis. A set of novel peroxidases, named peroxiredoxins (Prx), regulate the intracellular concentration of H2O2 by reducing it in the presence of an appropriate electron donor. The crystal structure of a human Prx enzyme, hORF6, reveals that the protein contains two discrete domains and forms a dimer. The N-terminal domain has a thioredoxin fold and the C-terminal domain is used for dimerization. The active site cysteine (Cys 47), which exists as cysteine-sulfenic acid in the crystal, is located at the bottom of a relatively narrow pocket. The positively charged environment surrounding Cys 47 accounts for the peroxidase activity of the enzyme, which contains no redox cofactors.

    Nature structural biology 1998;5;5;400-6

  • Characterization of a mammalian peroxiredoxin that contains one conserved cysteine.

    Kang SW, Baines IC and Rhee SG

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

    A new type of peroxidase enzyme, named thioredoxin peroxidase (TPx), that reduces H2O2 with the use of electrons from thioredoxin and contains two essential cysteines was recently identified. TPx homologs, termed peroxiredoxin (Prx), have also been identified and include several proteins, designated 1-Cys Prx, that contain only one conserved cysteine. Recombinant human 1-Cys Prx expressed in and purified from Escherichia coli has now been shown to reduce H2O2 with electrons provided by dithiothreitol. Furthermore, human 1-Cys Prx transiently expressed in NIH 3T3 cells was able to remove intracellular H2O2 generated in response either to the addition of exogenous H2O2 or to treatment with platelet-derived growth factor. The conserved Cys47-SH group was shown to be the site of oxidation by H2O2. Thus, mutation of Cys47 to serine abolished peroxidase activity. Moreover, the oxidized intermediate appears to be Cys-SOH. In contrast to TPx, in which one of the two conserved cysteines is oxidized to Cys-SOH and then immediately reacts with the second conserved cysteine of the second subunit of the enzyme homodimer to form an intermolecular disulfide, the Cys-SOH of 1-Cys Prx does not form a disulfide. Neither thioredoxin, which reduces the disulfide of TPx, nor glutathione, which reduces the Cys-SeOH of oxidized glutathione peroxidase, was able to reduce the Cys-SOH of 1-Cys Prx and consequently could not support peroxidase activity. Human 1-Cys Prx was previously shown to exhibit a low level of phospholipase A2 activity at an acidic pH; the enzyme was thus proposed to be lysosomal, and Ser32 was proposed to be critical for lipase function. However, the mutation of Ser32 or Cys47 has now been shown to have no effect on the lipase activity of 1-Cys Prx, which was also shown to be a cytosolic protein. Thus, the primary cellular function of 1-Cys Prx appears to be to reduce peroxides with the use of electrons provided by an as yet unidentified source; the enzyme therefore represents a new type of peroxidase.

    The Journal of biological chemistry 1998;273;11;6303-11

  • The human homologue of a bovine non-selenium glutathione peroxidase is a novel keratinocyte growth factor-regulated gene.

    Frank S, Munz B and Werner S

    Max-Planck-Institut für Biochemie, Martinsried, Germany.

    Keratinocyte growth factor is a potent and specific mitogen for different types of epithelial cells, including keratinocytes of the skin. Furthermore, it has been implicated in morphogenetic processes of several organs. To further define the mechanisms of KGF action in the skin, we attempted to identify genes which are regulated by KGF in keratinocytes. Using the differential display RT-PCR technology, a gene was identified which was strongly induced in these cells by treatment with KGF but not with serum growth factors or pro-inflammatory cytokines. Molecular cloning of the full-length cDNA revealed a strong homology of the corresponding gene product with a bovine non-selenium glutathione peroxidase. Upon transfection of COS cells with the full-length cDNA, a 27 kD cytoplasmic protein was obtained which had the expected size of glutathione peroxidase. Expression of the novel gene was detected in normal human skin and at particularly high levels in psoriatic skin, indicating a possible in vivo function of the protein in this tissue. Identification of a peroxidase as a KGF-regulated gene suggests that prevention from oxygen toxicity is a novel and specific mechanism of KGF action.

    Oncogene 1997;14;8;915-21

  • Identification of a human cDNA clone for lysosomal type Ca2+-independent phospholipase A2 and properties of the expressed protein.

    Kim TS, Sundaresh CS, Feinstein SI, Dodia C, Skach WR, Jain MK, Nagase T, Seki N, Ishikawa K, Nomura N and Fisher AB

    University of Pennsylvania Medical Center, Philadelphia 19104, USA.

    A Ca2+-independent phospholipase A2 (PLA2) maximally active at pH 4 and specifically inhibited by the transition-state analogue 1-hexadecyl-3-trifluoroethylglycero-sn-2-phosphomethanol (MJ33) was isolated from rat lungs. The sequence for three internal peptides (35 amino acids) was used to identify a 1653-base pair cDNA clone (HA0683) from a human myeloblast cell line. The deduced protein sequence of 224 amino acids contained a putative motif (GXSXG) for the catalytic site of a serine hydrolase, but showed no significant homology to known phospholipases. Translation of mRNA produced from this clone in both a wheat germ system and Xenopus oocytes showed expression of PLA2 activity with properties similar to the rat lung enzyme. Apparent kinetic constants for PLA2 with dipalmitoylphosphatidylcholine as substrate were Km = 0.25 mM and Vmax = 1.89 nmol/h. Activity with alkyl ether phosphatidylcholine as substrate was decreased significantly compared with diacylphosphatidylcholine. Significant lysophospholipase, phospholipase A1, or 1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine acetylhydrolase activity was not observed. Enzyme activity was insensitive to p-bromophenacyl bromide, bromoenol lactone, trifluoromethylarachidonoyl ketone, mercaptoethanol, and ATP, but was inhibited by MJ33 and diethyl p-nitrophenyl phosphate, a serine protease inhibitor. SDS-polyacrylamide gel electrophoresis with autoradiography of the translated [35S]methionine-labeled protein confirmed a molecular mass of 25.8 kDa, in good agreement with the enzyme isolated from rat lung. By Northern blot analysis, mRNA corresponding to this clone was present in both rat lung and isolated rat granular pneumocytes. These results represent the first molecular cloning of a cDNA for the lysosomal type Ca2+-independent phospholipase A2 group of enzymes.

    Funded by: NCI NIH HHS: CA 01614; NHLBI NIH HHS: HL 19737

    The Journal of biological chemistry 1997;272;4;2542-50

  • Prediction of the coding sequences of unidentified human genes. III. The coding sequences of 40 new genes (KIAA0081-KIAA0120) deduced by analysis of cDNA clones from human cell line KG-1.

    Nagase T, Miyajima N, Tanaka A, Sazuka T, Seki N, Sato S, Tabata S, Ishikawa K, Kawarabayasi Y, Kotani H et al.

    Kazusa DNA Research Institute, Chiba, Japan.

    We isolated full-length cDNA clones from size-fractionated cDNA libraries of human immature myeloid cell line KG-1, and the coding sequences of 40 genes were newly predicted. A computer search of the GenBank/EMBL databases indicated that the sequences of 14 genes were unrelated to any reported genes, while the remaining 26 genes carried some sequences with similarities to known genes. Significant transmembrane domains were identified in 17 genes, and protein motifs that matched those in the PROSITE motif database were identified in 11 genes. Northern hybridization analysis with 18 different cells and tissues demonstrated that 10 genes were apparently expressed in a cell-specific or tissue-specific manner. Among the genes predicted, half were isolated from the medium-sized cDNA library and the other half from the small-sized cDNA library, and their average sizes were 4 kb and 1.4 kb, respectively. As judged by Northern hybridization profiles, small-sized cDNAs appeared to be expressed more ubiquitously and abundantly in various tissues, compared with that of medium-sized cDNAs.

    DNA research : an international journal for rapid publication of reports on genes and genomes 1995;2;1;37-43

  • Plasma and red blood cell protein maps: update 1993.

    Golaz O, Hughes GJ, Frutiger S, Paquet N, Bairoch A, Pasquali C, Sanchez JC, Tissot JD, Appel RD, Walzer C et al.

    Medicine Department, Geneva University.

    This publication updates the reference plasma and red blood cell protein maps obtained with immobilized pH gradients. Seventeen polypeptide spots or chains were partially characterized by direct N-terminal sequencing or by sequencing of peptides obtained from enzymatic digestion. Additional new polypeptides and previously known proteins are listed in a table and/or labeled on the protein maps, thus providing the 1993 update of the human plasma and red blood cell two-dimensional gel SWISS-2DPAGE database. SWISS-2DPAGE and the SWISS-PROT protein sequence databases are closely linked together through the use of common accession numbers.

    Electrophoresis 1993;14;11;1223-31

  • Human liver protein map: a reference database established by microsequencing and gel comparison.

    Hochstrasser DF, Frutiger S, Paquet N, Bairoch A, Ravier F, Pasquali C, Sanchez JC, Tissot JD, Bjellqvist B, Vargas R et al.

    Medicine Department, Geneva University, Switzerland.

    This publication establishes a reference human liver protein map obtained with immobilized pH gradients. By microsequencing, 57 spots or 42 polypeptide chains were identified. By protein map comparison and matching (liver, red blood cell and plasma sample maps), 8 additional proteins were identified. The new polypeptides and previously known proteins are listed in a table and/or labeled on the protein map, thus providing a human liver two-dimensional gel database. This reference map can be used to identify protein spots on other samples such as rectal cancer biopsies.

    Electrophoresis 1992;13;12;992-1001

  • Treatment of Haemophilus aphrophilus endocarditis with ciprofloxacin.

    Dawson SJ and White LA

    Department of Microbiology, Southampton General Hospital, U.K.

    A patient with Haemophilus aphrophilus endocarditis was successfully treated with ciprofloxacin. The response to treatment with cefotaxime and netilmicin for 12 days was poor but was satisfactory to a 6 weeks' course of ciprofloxacin.

    The Journal of infection 1992;24;3;317-20

  • Phospholipases A2 and C of human lung; subcellular distribution and substrate selectivity.

    Yeats DA and Bakhle YS

    Department of Pharmacology, Hunterian Institute, Royal College of Surgeons, London, U.K.

    The phospholipase activities of cell-free extracts of human lung were studied using sn-2-arachidonoyl phospholipids. Samples of human lung obtained during surgery were homogenized and separated by centrifugation into three fractions: P1, containing mitochondrial and lysosomal marker enzymes; P2, with microsomal enzymes; and S2, with cytosolic enzymes. The highest phospholipase activities were in the microsomal fraction, using any of the three substrates, [14C]arachidonoylphosphatidylcholine (PC), [14C]arachidonoylphosphatidylethanolamine (PE) and [14C]arachidonoylphosphatidylinositol (PI). From PC and PE, only free arachidonic acid was formed, suggesting the presence of a phospholipase A2 (PLA2)-like activity. From PI, two metabolites were produced, diacylglycerol and arachidonic acid, suggesting the presence of a PI-specific PLC activity. Rates of hydrolysis were highest for PI, followed by PE and then PC. Hydrolysis of [14C]arachidonoyl-PC was compared to that of [14C]oleoyl-PC and found to be similarly distributed and of comparable velocity. The distribution and relative activities of phospholipases in rat lung homogenates were very similar to those in human lung.

    Funded by: Wellcome Trust

    Biochimica et biophysica acta 1989;1003;2;189-95

  • Work in progress. Occurence of phospholipase A1 and A2 in human decidua.

    Akesson B

    Phospholipase A2, an enzyme which may regulate the formation of polyunsaturated fatty acids utilized for prostaglandin synthesis, was found to have significant higher activity in decidual than in myometrial tissue. The major part of phospholipase A2 in the decidua had an acid pH optimum, which indicates that most of the enzyme is stored in the lysosomes of this tissue. These findings, together with previous observations, lend further support to the view that lysosomal phospholipase A2 released within decidual cells might be a trigger of abortion and parturition.

    Prostaglandins 1975;9;5;667-73

Gene lists (7)

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
L00000010 G2C Homo sapiens Human mitochondria Human orthologues of mouse mitochondria adapted from Collins et al (2006) 91
L00000011 G2C Homo sapiens Human clathrin Human orthologues of mouse clathrin coated vesicle genes adapted from Collins et al (2006) 150
L00000012 G2C Homo sapiens Human Synaptosome Human orthologues of mouse synaptosome adapted from Collins et al (2006) 152
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
L00000069 G2C Homo sapiens BAYES-COLLINS-HUMAN-PSD-FULL Human cortex biopsy PSD full list 1461
© 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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