G2Cdb::Gene report

Gene id
G00001326
Gene symbol
ATP1B1 (HGNC)
Species
Homo sapiens
Description
ATPase, Na+/K+ transporting, beta 1 polypeptide
Orthologue
G00000077 (Mus musculus)

Databases (9)

Curated Gene
OTTHUMG00000034590 (Vega human gene)
Gene
ENSG00000143153 (Ensembl human gene)
481 (Entrez Gene)
415 (G2Cdb plasticity & disease)
ATP1B1 (GeneCards)
Literature
182330 (OMIM)
Marker Symbol
HGNC:804 (HGNC)
Protein Expression
1989 (human protein atlas)
Protein Sequence
P05026 (UniProt)

Literature (39)

Pubmed - other

  • Follow-up of a major linkage peak on chromosome 1 reveals suggestive QTLs associated with essential hypertension: GenNet study.

    Ehret GB, O'Connor AA, Weder A, Cooper RS and Chakravarti A

    Center for Complex Diseases Genomics, McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.

    Essential hypertension is a major cardiovascular risk factor and a large proportion of this risk is genetic. Identification of genomic regions consistently associated with hypertension has been difficult in association studies to date as this requires large sample sizes.We previously published a large genome-wide linkage scan in Americans of African (AA) and European (EA) descent in the GenNet Network of the Family Blood Pressure Program (FBPP). A highly significant linkage peak was identified on chr1q spanning a region of 100 cM. In this study, we genotyped 1569 SNPs under this linkage peak in 2379 individuals to identify whether common genetic variants were associated with blood pressure (BP) at this locus.Our analysis, using two different family-based association tests, provides suggestive evidence (P< or =2 x 10(-5)) for a collection of single nucleotide polymorphisms (SNPs) associated with BP. In EAs, using diastolic BP as a quantitative phenotype, three variants located in or near the GPA33, CD247, and F5 genes, emerge as our top hits; for systolic BP, variants in GPA33, CD247, and REN are our best findings. No variant in AAs came close to suggestive evidence after multiple-test corrections (P> or =8 x 10(-5)). In summary, we show that systematic follow-up of a linkage signal can help discover candidate variants for essential hypertension that require a follow-up in yet larger samples. The failure to identify common variants is either because of low statistical power or the existence of rare coding variants in specific families or both, which require additional studies to clarify.

    Funded by: NHLBI NIH HHS: U01 HL054512-11

    European journal of human genetics : EJHG 2009;17;12;1650-7

  • Expression of Na,K-ATPase-beta(1) subunit increases uptake and sensitizes carcinoma cells to oxaliplatin.

    Tummala R, Wolle D, Barwe SP, Sampson VB, Rajasekaran AK and Pendyala L

    Department of Medicine, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14263, USA.

    Purpose: The ovarian carcinoma subline A2780/C10B (C10B) is an oxaliplatin resistant clone derived from the human ovarian carcinoma cell line A2780. The C10B cells are characterized by mesenchymal phenotype, decreased platinum uptake and increased glutathione levels (Hector et al. in Cancer Lett 245:195-204, 2007; Varma et al. in Oncol Rep 14:925-932, 2005). Na,K-ATPase-beta subunit (Na,K-beta(1)) functions as a cell-cell adhesion molecule in epithelial cells and is reduced in a variety of carcinoma cells that show mesenchymal phenotype. The purpose of this study is to evaluate the relationship between Na,K-beta expression and sensitivity to oxaliplatin.

    Methods: Cell lines used include A2780, C10B, C10B transfected with Na,K-beta(1) (C10B-Na,K-beta) and a canine kidney carcinoma cell line MSV-MDCK also transfected with Na,K-beta(1) (MSV-MDCK-beta subunit). Cytotoxicity studies were performed by sulforhodamine-blue assay. The Na,K-alpha(1) and Na,K-beta(1) subunit localization and expression were by immunofluorescence microscopy and Western blot analysis. Platinum accumulation measurements were by atomic absorption spectrophotometry.

    Results: C10B cells express highly reduced levels of Na,K-beta(1) subunit. Exogenous expression of Na,K-beta(1) increased platinum accumulation and sensitized C10B cells to oxaliplatin. The pharmacological inhibitor of Na,K-ATPase ouabain did not alter the oxaliplatin accumulation indicating that Na,K-beta(1) sensitizes cells in a Na,K-ATPase enzyme activity independent manner. These findings were also confirmed in MSV-MDCK-beta subunit cells.

    Conclusions: This study for the first time reveals that reduced expression of the Na,K-beta(1) protein is associated with oxaliplatin resistance in cancer cells and demonstrates a novel role for this protein in sensitizing the cells to oxaliplatin. This study suggests a potentially important role for Na,K-beta(1) in both prognosis and therapy of oxaliplatin resistant malignancies.

    Funded by: NCI NIH HHS: CA109619; NIDDK NIH HHS: DK56216

    Cancer chemotherapy and pharmacology 2009;64;6;1187-94

  • A C-terminal lobe of the beta subunit of Na,K-ATPase and H,K-ATPase resembles cell adhesion molecules.

    Bab-Dinitz E, Albeck S, Peleg Y, Brumfeld V, Gottschalk KE and Karlish SJ

    Department of Biological Chemistry, Weizmann Institute of Science, Rehovoth 76100, Israel.

    The beta subunit of Na,K-ATPase is required for stabilization and maturation of the catalytic alpha subunits and is also involved in cell adhesion and establishing epithelial cell polarity. However, the mechanism of cell adhesion effects and protein partners of beta are unknown. We have applied fold recognition methods to predict that a C-terminal domain of the beta subunits of Na,K-ATPase and H,K-ATPase has an immunoglobulin-like fold, which resembles cell adhesion molecules. Comparison of the predicted C-terminal domain with a recently published structure of shark rectal gland Na,K-ATPase at 2.4 A in which alpha, beta, and FXYD subunits were resolved confirms that the beta subunit ectodomain contains an immunoglobulin-like structure. Expression in Escherichia coli of a sequence corresponding to the C-terminal domain, followed by its purification, refolding, and circular dichroism analysis, shows that the domain is independently stable with prominent beta sheet secondary structure, as predicted. Proteolytic digestion of the purified detergent-soluble recombinant Na,K-ATPase (alpha1beta1) is also indicative of a stable C-terminal domain of beta in the native complex. The major conclusion of this work is consistent with prior evidence for a role of the beta subunit in cell-cell adhesion, and it attributes that function largely to the C-terminal lobe of the beta ectodomain. In the light of these findings, we discuss its role in cell adhesion and recognition of the beta subunits of Na,K-ATPase, including potential protein partners.

    Biochemistry 2009;48;36;8684-91

  • Association of ATP1B1 single-nucleotide polymorphisms with blood pressure and hypertension in a Chinese population.

    Xiao B, Zhang Y, Niu W, Gao P and Zhu D

    State Key Laboratory of Medical Genomics, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China.

    Background: ATP1B1 encodes the beta subunits of Na/K ATPase which plays an important role in maintaining the normal gradients of Na(+) and K(+) across plasma membrane. A recent study demonstrated an association of ATP1B1 genetic variations with blood pressure (BP) in Americans. We aimed to investigate the association between ATP1B1 polymorphisms with BP and hypertension in a Chinese population.

    Twelve tag single-nucleotide polymorphisms (SNPs) of ATP1B1 were genotyped in 906 patients with essential hypertension (EH) and 894 normotensives (NT).

    Results: None of the selected SNPs was associated with hypertension. However, an overall significant association of haplotypes containing rs1200131, rs1200137, rs3766032, rs3766039 and rs2982468 with hypertension was observed (p=0.032). A common haplotype (G-T-A-C-T) was associated with an increased risk for hypertension (OR(adjusted)=1.717, p=0.033). In NT subjects, rs3766032AA carriers had lower systolic BP (SBP) and diastolic BP (DBP) than AG/GG carriers (SBP, 112.6+/-10.0 mmHg vs. 115.5+/-10.6 mmHg, p<0.05; DBP, 75.1+/-6.8 mmHg vs. 76.8+/-6.0 mmHg, p<0.05), and rs2982468 TT carriers had lower DBP than AT/AA carriers (74.8+/-6.9 mmHg vs. 76.3+/-6.2 mmHg; p<0.01) after correction. In NT subjects, BP showed an overall significant association with haplotypes (p=0.006, for SBP and p=0.036, for DBP).

    Conclusion: We conclude that haplotype in ATP1B1 may confer susceptibility to BP regulation and hypertension in this Chinese population.

    Clinica chimica acta; international journal of clinical chemistry 2009;407;1-2;47-50

  • Reversible oxidative modification: a key mechanism of Na+-K+ pump regulation.

    Figtree GA, Liu CC, Bibert S, Hamilton EJ, Garcia A, White CN, Chia KK, Cornelius F, Geering K and Rasmussen HH

    Department of Cardiology, Royal North Shore Hospital, University of Sydney, St Leonards NSW 2065, Australia.

    Angiotensin II (Ang II) inhibits the cardiac sarcolemmal Na(+)-K(+) pump via protein kinase (PK)C-dependent activation of NADPH oxidase. We examined whether this is mediated by oxidative modification of the pump subunits. We detected glutathionylation of beta(1), but not alpha(1), subunits in rabbit ventricular myocytes at baseline. beta(1) Subunit glutathionylation was increased by peroxynitrite (ONOO(-)), paraquat, or activation of NADPH oxidase by Ang II. Increased glutathionylation was associated with decreased alpha(1)/beta(1) subunit coimmunoprecipitation. Glutathionylation was reversed after addition of superoxide dismutase. Glutaredoxin 1, which catalyzes deglutathionylation, coimmunoprecipitated with beta(1) subunit and, when included in patch pipette solutions, abolished paraquat-induced inhibition of myocyte Na(+)-K(+) pump current (I(p)). Cysteine (Cys46) of the beta(1) subunit was the likely candidate for glutathionylation. We expressed Na(+)-K(+) pump alpha(1) subunits with wild-type or Cys46-mutated beta(1) subunits in Xenopus oocytes. ONOO(-) induced glutathionylation of beta(1) subunit and a decrease in Na(+)-K(+) pump turnover number. This was eliminated by mutation of Cys46. ONOO(-) also induced glutathionylation of the Na(+)-K(+) ATPase beta(1) subunit from pig kidney. This was associated with a approximately 2-fold decrease in the rate-limiting E(2)-->E(1) conformational change of the pump, as determined by RH421 fluorescence. We propose that kinase-dependent regulation of the Na(+)-K(+) pump occurs via glutathionylation of its beta(1) subunit at Cys46. These findings have implications for pathophysiological conditions characterized by neurohormonal dysregulation, myocardial oxidative stress and raised myocyte Na(+) levels.

    Circulation research 2009;105;2;185-93

  • Common variants at ten loci modulate the QT interval duration in the QTSCD Study.

    Pfeufer A, Sanna S, Arking DE, Müller M, Gateva V, Fuchsberger C, Ehret GB, Orrú M, Pattaro C, Köttgen A, Perz S, Usala G, Barbalic M, Li M, Pütz B, Scuteri A, Prineas RJ, Sinner MF, Gieger C, Najjar SS, Kao WH, Mühleisen TW, Dei M, Happle C, Möhlenkamp S, Crisponi L, Erbel R, Jöckel KH, Naitza S, Steinbeck G, Marroni F, Hicks AA, Lakatta E, Müller-Myhsok B, Pramstaller PP, Wichmann HE, Schlessinger D, Boerwinkle E, Meitinger T, Uda M, Coresh J, Kääb S, Abecasis GR and Chakravarti A

    Institute of Human Genetics, Helmholtz Center Munich, Germany. arne.pfeufer@helmholtz-muenchen.de

    The QT interval, a measure of cardiac repolarization, predisposes to ventricular arrhythmias and sudden cardiac death (SCD) when prolonged or shortened. A common variant in NOS1AP is known to influence repolarization. We analyze genome-wide data from five population-based cohorts (ARIC, KORA, SardiNIA, GenNOVA and HNR) with a total of 15,842 individuals of European ancestry, to confirm the NOS1AP association and identify nine additional loci at P < 5 x 10(-8). Four loci map near the monogenic long-QT syndrome genes KCNQ1, KCNH2, SCN5A and KCNJ2. Two other loci include ATP1B1 and PLN, genes with established electrophysiological function, whereas three map to RNF207, near LITAF and within NDRG4-GINS3-SETD6-CNOT1, respectively, all of which have not previously been implicated in cardiac electrophysiology. These results, together with an accompanying paper from the QTGEN consortium, identify new candidate genes for ventricular arrhythmias and SCD.

    Funded by: Intramural NIH HHS; NCRR NIH HHS: UL1 RR025005; NHGRI NIH HHS: U01 HG004402; NHLBI NIH HHS: HL054512, HL86694, N01-HC-55015, N01-HC-55016, N01-HC-55018, N01-HC-55019, N01-HC-55020, N01-HC-55021, N01-HC-55022, N01HC55015, N01HC55016, N01HC55018, N01HC55019, N01HC55020, N01HC55021, N01HC55022, R01 HL059367, R01 HL086694, R01 HL086694-03, R01 HL087641, R01 HL59367, U01 HL054512, U01 HL054512-13, U10 HL054512; NIA NIH HHS: N01-AG-12109; PHS HHS: 263-MA-410953, HHSN 268200625226C

    Nature genetics 2009;41;4;407-14

  • Pre-B-cell leukemia homeobox 1 (PBX1) shows functional and possible genetic association with bone mineral density variation.

    Cheung CL, Chan BY, Chan V, Ikegawa S, Kou I, Ngai H, Smith D, Luk KD, Huang QY, Mori S, Sham PC and Kung AW

    Department of Medicine, The University of Hong Kong, Hong Kong, Republic of China.

    Bone mineral density (BMD) is one of the major determinants of risk for osteoporotic fracture. Multiple studies reveal that peak bone mass is under strong genetic influence. One of the major susceptibility loci for peak spine BMD has been mapped to chromosome 1q21-q23 in the Caucasian population. We have previously replicated this finding in Southern Chinese pedigrees and detected a maximum multipoint log of odds (LOD) score of 2.36 in this region. To further fine-map this region, 380 single-nucleotide polymorphic (SNP) markers were genotyped in 610 sibpairs from 231 families. Several markers were identified in the association analysis as important candidates underlying BMD variation. Among them, successful replication was demonstrated for SNPs in pre-B-cell leukemia homeobox 1 (PBX1) gene in two other unrelated case-control cohorts. The functional role of PBX1 in bone metabolism was examined in vitro using human bone-derived cells (HBDC) and murine MC3T3-E1 pre-osteoblasts. PBX1 mRNA was constitutively expressed in both HBDC and MC3T3-E1 cells. Immunostaining revealed that PBX1 is localized in the nucleus compartment. Silencing of PBX1 by RNAi in MC3T3-E1 cells decreased the expression of Runx2 and Osterix, the critical transcription factors for osteogenesis, but accelerated cell proliferation and bone nodule formation. Overall, our data suggest a genetic and functional association of PBX1 with BMD.

    Human molecular genetics 2009;18;4;679-87

  • Regulation of the bHLH transcription factor E2A in epithelial cells by interaction with the Na/K-ATPase beta1 subunit.

    Plotkin M and Pelger L

    New York Medical College, Renal Research Division, BSB C06, 95 Grasslands Road, Valhalla, NY 10595, USA. matthew_plotkin@nymc.edu

    The bHLH transcription factor E2A controls proliferation and differentiation in many cell types including kidney epithelial cells. To identify regulatory binding partners of E2A in the kidney, a yeast two-hybrid assay with a human adult kidney cDNA library was performed. Results demonstrated E2A interactions with other HLH proteins including Id1-3 and Pod1 and the Na/K-ATPase beta1 subunit. The specificity of beta1 subunit binding was confirmed by co-immunoprecipitation of E2A and beta1 subunit deletion constructs in HEK cells demonstrating E2A binding to the cytoplasmic tail of the beta1 subunit. Immunofluorescence and Western analysis of HEK cells co-transfected with GFP-beta1 subunit and E2A demonstrated E2A membrane binding and increased beta1 subunit membrane localization. Increased beta1 subunit expression resulted in decreased nuclear E2A expression and protein half-life and reduced E2A induced gene expression. These results suggest that E2A and Na/K-ATPase beta1 subunit expression in epithelial cells are regulated by interactions between these proteins.

    Archives of biochemistry and biophysics 2008;480;1;68-74

  • Fast degradation of the auxiliary subunit of Na+/K+-ATPase in the plasma membrane of HeLa cells.

    Yoshimura SH, Iwasaka S, Schwarz W and Takeyasu K

    Graduate School of Biostudies, Kyoto University, Yoshida-konoe-cho, Sakyo-ku, Kyoto, 606-8502, Japan. yoshimura@lif.kyoto-u.ac.jp

    The cell-surface expression and function of multisubunit plasma membrane proteins are regulated via interactions between catalytic subunits and auxiliary subunits. Subunit assembly in the endoplasmic reticulum is required for the cell-surface expression of the enzyme, but little is known about subunit interactions once it reaches the plasma membrane. Here we performed highly quantitative analyses of the catalytic (alpha1) and auxiliary (beta1 and beta3) subunits of Na(+)/K(+)-ATPase in the HeLa cell plasma membrane using isoform-specific antibodies and a cell-surface protein labeling procedure. Our results indicate that although the beta-subunit is required for the cell-surface expression of the alpha-subunit, the plasma membrane contains more alpha-subunits than beta-subunits. Pulse-labeling and chasing of the cell-surface proteins revealed that degradation of the beta-subunits was much faster than that of the alpha1-subunit. Ubiquitylation, as well as endocytosis, was involved in the fast degradation of the beta1-subunit. Double knockdown of the beta1- and beta3-subunits by RNAi resulted in the disappearance of these beta-subunits but not the alpha1-subunit in the plasma membrane. All these results indicate that the alpha- and beta-subunits of Na(+)/K(+)-ATPase are assembled in the endoplasmic reticulum, but are disassembled in the plasma membrane and undergo different degradation processes.

    Journal of cell science 2008;121;Pt 13;2159-68

  • Sodium-potassium ATPase 1 subunit is a molecular partner of Wolframin, an endoplasmic reticulum protein involved in ER stress.

    Zatyka M, Ricketts C, da Silva Xavier G, Minton J, Fenton S, Hofmann-Thiel S, Rutter GA and Barrett TG

    Section of Medical and Molecular Genetics, The Medical School, University of Birmingham, Birmingham B15 2TT, UK.

    Wolfram syndrome, an autosomal recessive disorder characterized by diabetes mellitus and optic atrophy, is caused by mutations in the WFS1 gene encoding an endoplasmic reticulum (ER) membrane protein, Wolframin. Although its precise functions are unknown, Wolframin deficiency increases ER stress, impairs cell cycle progression and affects calcium homeostasis. To gain further insight into its function and identify molecular partners, we used the WFS1-C-terminal domain as bait in a yeast two-hybrid screen with a human brain cDNA library. Na+/K+ ATPase beta1 subunit was identified as an interacting clone. We mapped the interaction to the WFS1 C-terminal and transmembrane domains, but not the N-terminal domain. Our mapping data suggest that the interaction most likely occurs in the ER. We confirmed the interaction by co-immunoprecipitation in mammalian cells and with endogenous proteins in JEG3 placental cells, neuroblastoma SKNAS and pancreatic MIN6 beta cells. Na+/K+ ATPase beta1 subunit expression was reduced in plasma membrane fractions of human WFS1 mutant fibroblasts and WFS1 knockdown MIN6 pancreatic beta-cells compared with wild-type cells; Na+/K+ ATPase alpha1 subunit expression was also reduced in WFS-depleted MIN6 beta cells. Induction of ER stress in wild-type cells only partly accounted for the reduced Na+/K+ ATPase beta1 subunit expression observed. We conclude that the interaction may be important for Na+/K+ ATPase beta1 subunit maturation; loss of this interaction may contribute to the pathology seen in Wolfram syndrome via reductions in sodium pump alpha1 and beta1 subunit expression in pancreatic beta-cells.

    Funded by: Diabetes UK: 13/0004672; Wellcome Trust

    Human molecular genetics 2008;17;2;190-200

  • Dynamic profiling of the post-translational modifications and interaction partners of epidermal growth factor receptor signaling after stimulation by epidermal growth factor using Extended Range Proteomic Analysis (ERPA).

    Wu SL, Kim J, Bandle RW, Liotta L, Petricoin E and Karger BL

    Barnett Institute, Northeastern University, Boston, Massachusetts 01225, USA.

    In a recent report, we introduced Extended Range Proteomic Analysis (ERPA), an intermediate approach between top-down and bottom-up proteomics, for the comprehensive characterization at the trace level (fmol level) of large and complex proteins. In this study, we extended ERPA to determine quantitatively the temporal changes that occur in the tyrosine kinase receptor, epidermal growth factor receptor (EGFR), upon stimulation. Specifically A 431 cells were stimulated with epidermal growth factor after which EGFR was immunoprecipitated at stimulation times of 0, 0.5, 2, and 10 min as well as 4 h. High sequence coverage was obtained (96%), and methods were developed for label-free quantitation of phosphorylation and glycosylation. A total of 13 phosphorylation sites were identified, and the estimated stoichiometry was determined over the stimulation time points, including Thr(P) and Ser(P) sites in addition to Tyr(P) sites. A total of 10 extracellular domain N-glycan sites were also identified, and major glycoforms at each site were quantitated. No change in the extent of glycosylation with stimulation was observed as expected. Finally potential binding partners to EGFR were identified based on changes in the amount of protein pulled down with EGFR as a function of time of stimulation. Many of the 19 proteins identified are known binding partners of EGFR. This work demonstrates that comprehensive characterization provides a powerful tool to aid in the study of important therapeutic targets. The detailed molecular information will prove useful in future studies in tissue.

    Funded by: Intramural NIH HHS; NIGMS NIH HHS: GM 15847

    Molecular & cellular proteomics : MCP 2006;5;9;1610-27

  • Regulation of the Na-K-ATPase beta(1)-subunit promoter by multiple prostaglandin-responsive elements.

    Matlhagela K and Taub M

    Biochemistry Department, School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, New York 14214, USA.

    Renal prostaglandins modulate the activity of a number of the transport systems in the kidney, including the Na-K-ATPase. Not only do prostaglandins have acute affects on renal Na-K-ATPase, but in addition prostaglandins have chronic affects, which include regulation at the transcriptional level. Previously, we have presented evidence that one such prostaglandin, PGE(1), stimulates the transcription of the human Na-K-ATPase beta(1)-subunit gene in Madin-Darby canine kidney cells via cAMP- and Ca(2+)-mediated pathways (Taub M, Borsick M, Geisel J, Matlhagela K, Rajkhowa T, and Allen C. Exp Cell Res 299: 1-14, 2004; Matlhagela K, Borsick M, Rajkhowa T, and Taub M. J Biol Chem 280: 334-346, 2005). Evidence was presented indicating that PGE(1) stimulation was mediated through the binding of cAMP-regulatory element binding protein (CREB) to a prostaglandin-responsive element (PGRE) as well as Sp1 binding to an adjacent Sp1 site. In this report, we present evidence from EMSAs and DNA affinity precipitation studies that another PGRE present in the Na-K-ATPase beta(1)-subunit promoter similarly binds CREB and Sp1. The evidence that indicates a requirement for CREB as well as Sp1 for gene activation through both PGREs (PGRE1 and PGRE3) includes studies with a dominant negative CREB (KCREB), Drosophila SL2 cells, and PGRE mutants. The results of these studies are indicative of a synergism between Sp1 and CREB in mediating regulation by PGRE3; while regulation occurring through PGRE1 also involves Sp1 and CREB, the mechanism appears to be distinct.

    Funded by: NHLBI NIH HHS: 1R01-HL-69676-01

    American journal of physiology. Renal physiology 2006;291;3;F635-46

  • A yeast 2-hybrid analysis of human GTP cyclohydrolase I protein interactions.

    Swick L and Kapatos G

    Department of Pharmacology, Wayne State University School of Medicine, Detroit, MI 48201, USA.

    The yeast 2-hybrid system was used to identify protein domains involved in the oligomerization of human guanosine 5'-triphosphate (GTP) Cyclohydrolase I (GCH1) and the interaction of GCH1 with its regulatory partner, GCH1 feedback regulatory protein (GFRP). When interpreted within the structural framework derived from crystallography, our results indicate that the GCH1 N-terminal alpha-helices are not the only domains involved in the formation of dimers from monomers and also suggest an important role for the C-terminal alpha-helix in the assembly of dimers to form decamers. Moreover, a previously unknown role of the extended N-terminal alpha-helix in the interaction of GCH1 and GFRP was revealed. To discover novel GCH1 protein binding partners, we used the yeast 2-hybrid system to screen a human brain library with GCH1 N-terminal amino acids 1-96 as prey. This protruding extension of GCH1 contains two canonical Type-I Src homology-3 (SH3) ligand domains located within amino acids 1-42. Our screen yielded seven unique clones that were subsequently shown to require amino acids 1-42 for binding to GCH1. The interaction of one of these clones, Activator of Heat Shock 90 kDa Protein (Aha1), with GCH1 was validated by glutathione-s-transferase (GST) pull-down assay. Although the physiological relevance of the Aha1-GCH1 interaction requires further study, Aha1 may recruit GCH1 into the endothelial nitric oxide synthase/heat shock protein (eNOS/Hsp90) complex to support changes in endothelial nitric oxide production through the local synthesis of BH4.

    Funded by: NINDS NIH HHS: NS 26081, R01 NS026081-18

    Journal of neurochemistry 2006;97;5;1447-55

  • 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

  • Thyrotoxic periodic paralysis and polymorphisms of sodium-potassium ATPase genes.

    Kung AW, Lau KS, Cheung WM and Chan V

    Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong SAR, China. awckung@hkucc.hku.hk

    Objective: Thyrotoxic periodic paralysis (TPP) is a complication of hyperthyroidism association with recurrent, reversible episodes of muscle weakness. Increased sodium-potassium ATPase (Na/K-ATPase) pump activity is postulated to contribute to the hypokalaemic paralytic attacks in TPP. The aim of this study was to determine the genetic predisposition to TPP in relation to Na/K-ATPase genes.

    Design: A case-control association study.

    Patients: Ninety-nine male Chinese TPP patients were compared to 84 male Graves' disease (GD) patients without TPP and 100 normal male controls.

    Measurement: A total of 1500 base pairs upstream of the transcriptional start site of the five Na/K-ATPase genes that are expressed in the skeletal muscles, namely ATP1A1, ATP1A2, ATP1B1, ATP1B2 and ATP1B4, were sequenced in all subjects for mutations or polymorphisms. The single nucleotide polymorphisms (SNPs) of the coding regions of the five genes were also studied for association with TPP.

    Results: No mutations were detected in the 5' regions of the five genes in any of the patients studied. There was no difference in the distribution of SNPs and SNP haplotypes in the upstream and coding region of these genes between the three groups of subjects.

    Conclusion: No association between the polymorphisms of ATP1A1, ATP1A2, ATP1B1, ATP1B2 and ATP1B4 genes and TPP could be detected.

    Clinical endocrinology 2006;64;2;158-61

  • Deglycosylation of Na+/K+-ATPase causes the basolateral protein to undergo apical targeting in polarized hepatic cells.

    Lian WN, Wu TW, Dao RL, Chen YJ and Lin CH

    Institute of Microbiology and Immunology, National Yang-Ming University, 155 Sec. 2 Linong Street, Taipei 112, Taiwan.

    Polarized epithelia, such as hepatocytes, target their integral membrane proteins to specific apical or basolateral membrane domains during or after biogenesis. The roles played by protein glycosylation in this sorting process remain controversial. We report here that deglycosylation treatments in well-polarized hepatic cells by deglycosylation drugs, or by site-directed mutagenesis of the N-linked-glycosylation residues, all cause the Na+/K+-ATPase beta-subunit to traffic from the native basolateral to the apical/canalicular domain. Deglycosylated beta-subunits are still able to bind and therefore transport the catalytic alpha-subunits to the aberrant apical location. Such apical targeting is mediated via the indirect transcytosis pathway. Cells containing apical Na+/K+-ATPase appear to be defective in maintaining the ionic gradient across the plasma membrane and in executing hepatic activities that are dependent upon the ionic homeostasis such as canalicular excretion.

    Journal of cell science 2006;119;Pt 1;11-22

  • Recombinant addition of N-glycosylation sites to the basolateral Na,K-ATPase beta1 subunit results in its clustering in caveolae and apical sorting in HGT-1 cells.

    Vagin O, Turdikulova S and Sachs G

    Department of Physiology, School of Medicine at UCLA, Los Angeles, California 90073, USA. olgav@ucla.edu

    In most polarized cells, the Na,K-ATPase is localized on the basolateral plasma membrane. However, an unusual location of the Na,K-ATPase was detected in polarized HGT-1 cells (a human gastric adenocarcinoma cell line). The Na,K-ATPase alpha1 subunit was detected along with the beta2 subunit predominantly on the apical membrane, whereas the Na,K-ATPase beta1 subunit was not found in HGT-1 cells. However, when expressed in the same cell line, a yellow fluorescent protein-linked Na,K-ATPase beta1 subunit was localized exclusively to the basolateral surface and resulted in partial redistribution of the endogenous alpha1 subunit to the basolateral membrane. The human beta2 subunit has eight N-glycosylation sites, whereas the beta1 isoform has only three. Accordingly, up to five additional N-glycosylation sites homologous to the ones present in the beta2 subunit were successively introduced in the beta1 subunit by site-directed mutagenesis. The mutated beta1 subunits were detected on both apical and basolateral membranes. The fraction of a mutant beta1 subunit present on the apical membrane increased in proportion to the number of glycosylation sites inserted and reached 80% of the total surface amount for the beta1 mutant with five additional sites. Clustered distribution and co-localization with caveolin-1 was detected by confocal microscopy for the endogenous beta2 subunit and the beta1 mutant with additional glycosylation sites but not for the wild type beta1 subunit. Hence, the N-glycans linked to the beta2 subunit of the Na,K-ATPase contain apical sorting information, and the high abundance of the beta2 subunit isoform, which is rich in N-glycans, along with the absence of the beta1 subunit, is responsible for the unusual apical location of the Na,K-ATPase in HGT-1 cells.

    Funded by: NIDDK NIH HHS: DK46917, DK53462, DK58333

    The Journal of biological chemistry 2005;280;52;43159-67

  • 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

  • Beta-amyloid protein converting enzyme 1 and brain-specific type II membrane protein BRI3: binding partners processed by furin.

    Wickham L, Benjannet S, Marcinkiewicz E, Chretien M and Seidah NG

    Laboratory of Biochemical Neuroendocrinology, Clinical Research Institute of Montreal, Montreal, Quebec, Canada.

    Using a yeast two-hybrid system, we screened a human brain cDNA library for possible interacting proteins with the C-terminal cytosolic tail of the beta-secretase beta-amyloid protein converting enzyme (BACE)1. This identified seven potential candidates, including the brain-specific type II membrane protein BRI3. Co-localization and co-immunoprecipitation experiments confirmed that BACE1 and BRI3 co-localize and interact with each other via the cytosolic tail of BACE1. Furthermore, pulse and pulse-chase analyses revealed that the pro-protein convertases furin, and to a lesser extent PC7 and PC5A, process BRI3 into a C-terminal secreted approximately 4-kDa product. Thus, furin efficiently processes both pro-BACE1 and its novel interacting protein pro-BRI3.

    Journal of neurochemistry 2005;92;1;93-102

  • 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

  • The carboxy terminus of the colonic H(+), K(+)-ATPase alpha-subunit is required for stable beta subunit assembly and function.

    Li J, Codina J, Petroske E, Werle MJ and DuBose TD

    Department of Internal Medicine, Section on Nephrology, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157, USA.

    Background: The present experiments were designed to study the importance of the carboxy-terminus of colonic H(+), K(+)-ATPase alpha-subunit (HKalpha(2)), for both function as well as integrity of assembly with beta1-Na(+), K(+)-ATPase.

    Methods: For this purpose, a mutation of 84 amino acids in the carboxy-terminus was created (DeltaHKalpha(2)) and HEK-293 cells were used as expression systems for functional studies using (86)Rb(+)-uptake, coimmunoprecipitation using specific antibodies and fluorescence microscopy using green fluorescent protein.

    Results: The results demonstrate that comparable levels of expression of HKalpha(2) and DeltaHKalpha(2) mRNA were observed when cells were cotransfected with beta1 subunit. However, the abundance of expression of full length HKalpha(2) protein exceeded that of the truncated protein DeltaHKalpha(2). Ouabain-sensitive (86)Rb(+)-uptake was present only in cells cotransfected with HKalpha(2)/beta(1), indicating that the mutation was incapable of sustaining functionality. Coimmunoprecipitation experiments demonstrated that HKalpha(2) protein was immunoprecipitated more abundantly than DeltaHKalpha(2) when coexpressed with beta1. The use of sucrose gradients and green fluorescence protein immunofluorescence demonstrated that while the DeltaHKalpha(2)/beta(1) complex was confined to the endoplasmic reticulum, the HKalpha(2)/beta(1) complex translocated to the plasma membrane.

    Conclusion: Taken together, our results are consistent with the view that the carboxy-terminus of HKalpha(2) facilitates the proper folding of the HKalpha(2)/beta(1) complex allowing translocation of the heterodimer to the plasma membrane where potassium uptake occurs. Otherwise, the alpha/beta complex is destined for degradation.

    Funded by: NIDDK NIH HHS: DK-30603

    Kidney international 2004;65;4;1301-10

  • Ischemia-induced phosphorylation of phospholemman directly activates rat cardiac Na/K-ATPase.

    Fuller W, Eaton P, Bell JR and Shattock MJ

    Cardiac Physiology, The Centre for Cardiovascular Biology and Medicine, The Rayne Institute, St. Thomas' Hospital, London SE1 7EH, UK.

    Regulation of the Na/K ATPase by protein kinases is model-specific. We have observed a profound activation of the sarcolemmal Na/K ATPase during cardiac ischemia, which is masked by an inhibitor of the enzyme in the cytosol. The aim of these studies was to characterize the pathways involved in this activation in the Langendorff-perfused rat heart. Na/K ATPase activity was determined by measuring ouabain-sensitive phosphate generation by cardiac homogenates at 37 degrees C. In isolated sarcolemma, ischemia (30 min) caused a substantial activation of the Na/K ATPase compared with aerobic controls, which was abolished by perfusing the heart with staurosporine or H89. However, the alpha1 subunit of the Na/K ATPase was not phosphorylated during ischemia. The sarcolemmal protein phospholemman (PLM) was found associated with the Na/K ATPase alpha1 and beta1 but not alpha2 subunits, and PLM increased its association with the catalytic subunit of PKA following ischemia. In vitro 14-3-3 binding assays indicated that PLM was phosphorylated following ischemia. These results indicate that the ischemia-induced activation of the Na/K ATPase is indirect, through phosphorylation of PLM, which is an integral part of the Na/K ATPase enzyme complex in the heart. The role of PLM is analogous to phospholamban in regulating the sarcoplasmic reticulum calcium ATPase.

    FASEB journal : official publication of the Federation of American Societies for Experimental Biology 2004;18;1;197-9

  • Identification and quantification of N-linked glycoproteins using hydrazide chemistry, stable isotope labeling and mass spectrometry.

    Zhang H, Li XJ, Martin DB and Aebersold R

    Institute for Systems Biology, 1441 N 34th Street, Seattle, Washington 98103-8904, USA.

    Quantitative proteome profiling using stable isotope protein tagging and automated tandem mass spectrometry (MS/MS) is an emerging technology with great potential for the functional analysis of biological systems and for the detection of clinical diagnostic or prognostic marker proteins. Owing to the enormous complexity of proteomes, their comprehensive analysis is an as-yet-unresolved technical challenge. However, biologically or clinically important information can be obtained if specific, information-rich protein classes, or sub-proteomes, are isolated and analyzed. Glycosylation is the most common post-translational modification. Here we describe a method for the selective isolation, identification and quantification of peptides that contain N-linked carbohydrates. It is based on the conjugation of glycoproteins to a solid support using hydrazide chemistry, stable isotope labeling of glycopeptides and the specific release of formerly N-linked glycosylated peptides via peptide- N-glycosidase F (PNGase F). The recovered peptides are then identified and quantified by MS/MS. We applied the approach to the analysis of plasma membrane proteins and proteins contained in human blood serum.

    Funded by: NCI NIH HHS: K08CA97282-01, R33 CA93302

    Nature biotechnology 2003;21;6;660-6

  • The immunoglobulin-superfamily molecule basigin is a binding protein for oligomannosidic carbohydrates: an anti-idiotypic approach.

    Heller M, von der Ohe M, Kleene R, Mohajeri MH and Schachner M

    Department of Neurobiology, Swiss Federal Institute of Technology, Zürich, Switzerland.

    Recognition molecules that carry carbohydrate structures regulate cell interactions during development and play important roles in synaptic plasticity and regeneration in the adult. Glycans appear to be involved in these interactions. We have searched for binding proteins for oligomannosidic structures using the L3 antibody directed against high mannose-type glycans in an anti-idiotypic approach. A selected monoclonal anti-idiotype antibody was used for affinity chromatography and identified basigin as a binding protein from mouse brain detergent lysates. Basigin was found to bind to high mannose-carrying cell recognition molecules, such as myelin-associated glycoprotein, L1, the beta2-subunit of Na+/K+-ATPase and an oligomannosidic neoglycolipid. Furthermore, basigin was involved in outgrowth of astrocytic processes in vitro. A striking homology between the first immunoglobulin (Ig)-like domain of basigin and the fourth Ig-like domain of NCAM, previously shown to bind to oligomannosidic glycans, and the lectin domain of the mannose receptor confirms that basigin is an oligomannose binding lectin. To our knowledge this is the first report that anti-idiotypic antibodies can be used to identify binding partners for carbohydrates.

    Journal of neurochemistry 2003;84;3;557-65

  • FXYD7 is a brain-specific regulator of Na,K-ATPase alpha 1-beta isozymes.

    Béguin P, Crambert G, Monnet-Tschudi F, Uldry M, Horisberger JD, Garty H and Geering K

    Institute of Pharmacology and Toxicology, University of Lausanne, rue du Bugnon 27, CH-1005 Lausanne, Switzerland.

    Recently, corticosteroid hormone-induced factor (CHIF) and the gamma-subunit, two members of the FXYD family of small proteins, have been identified as regulators of renal Na,K-ATPase. In this study, we have investigated the tissue distribution and the structural and functional properties of FXYD7, another family member which has not yet been characterized. Expressed exclusively in the brain, FXYD7 is a type I membrane protein bearing N-terminal, post-translationally added modifications on threonine residues, most probably O-glycosylations that are important for protein stabilization. Expressed in Xenopus oocytes, FXYD7 can interact with Na,K-ATPase alpha 1-beta 1, alpha 2-beta 1 and alpha 3-beta 1 but not with alpha-beta 2 isozymes, whereas, in brain, it is only associated with alpha 1-beta isozymes. FXYD7 decreases the apparent K(+) affinity of alpha 1-beta 1 and alpha 2-beta 1, but not of alpha 3-beta1 isozymes. These data suggest that FXYD7 is a novel, tissue- and isoform-specific Na,K-ATPase regulator which could play an important role in neuronal excitability.

    The EMBO journal 2002;21;13;3264-73

  • Isoforms of Na+, K+-ATPase in human prostate; specificity of expression and apical membrane polarization.

    Mobasheri A, Oukrif D, Dawodu SP, Sinha M, Greenwell P, Stewart D, Djamgoz MB, Foster CS, Martín-Vasallo P and Mobasheri R

    Department of Veterinary Preclinical Sciences, University of Liverpool, United Kingdom. A.Mobasheri@liverpool.ac.uk

    The cellular distribution of Na+, K+-ATPase subunit isoforms was mapped in the secretory epithelium of the human prostate gland by immunostaining with antibodies to the alpha and beta subunit isoforms of the enzyme. Immunolabeling of the alpha1, beta1 and beta2 isoforms was observed in the apical and lateral plasma membrane domains of prostatic epithelial cells in contrast to human kidney where the alpha1 and beta1 isoforms of Na+, K+-ATPase were localized in the basolateral membrane of both proximal and distal convoluted tubules. Using immunohistochemistry and PCR we found no evidence of Na+, K+-ATPase alpha2 and alpha3 isoform expression suggesting that prostatic Na+, K+-ATPase consists of alpha1/beta1 and alpha1/beta2 isozymes. Our immunohistochemical findings are consistent with previously proposed models placing prostatic Na+, K+-ATPase in the apical plasma membrane domain. Abundant expression of Na+, K+-ATPase in epithelial cells lining tubulo-alveoli in the human prostate gland confirms previous conclusions drawn from biochemical, pharmacological and physiological data and provides further evidence for the critical role of this enzyme in prostatic cell physiology and ion homeostasis. Na+, K+-ATPase most likely maintains an inwardly directed Na+ gradient essential for nutrient uptake and active citrate secretion by prostatic epithelial cells. Na+, K+-ATPase may also regulate lumenal Na+ and K+, major counter-ions for citrate.

    Histology and histopathology 2001;16;1;141-54

  • [Cell cycle and formation of active form of oxygen in rodent fibroblasts].

    Gamaleĭ IA, Polozov IuS, Aksenov ND, Darieva ZA, Kirpichnikova KM and Pospelova TV

    Institute of Cytology RAS, St. Petersburg.

    Changes in the levels of mRNAs encoding ion transporters (ATP1B1, NHE1, NKCC1), beta-actin, GAPDH, regulators of proliferation and apoptosis (p53, Bcl-2) and kinase hSGK, involved in cell water regulation, were studied using RT PCR in the peripheral human lymphocytes activated with phytohemagglutinin for 4-24 h. The common, "grouped", effect that was found was an increase in the levels of the studied mRNAs after an 8 h activation, sometimes preceded by a delay or slight decrease at the initial stage of 0-4 h. Apart from the common features, some differences were observed in the time courses and amplitudes of the responses of individual mRNAs. The arrangement of the individual mRNA responses in lymphocytes from different donors could differ significantly, thus indicating differential regulation of the studied mRNAs apart from the "grouped" effect. The data obtained confirmed our suggestion that regulation of ion transport at the level of mRNA could be involved in the changes of ion balance at the late stage of lymphocyte activation.

    Tsitologiia 2001;43;6;602-12

  • Cell-specific expression of the human Na+,K(+)-ATPase beta 2 subunit isoform in the nonpigmented ciliary epithelium.

    Coca-Prados M, Fernández-Cabezudo MJ, Sánchez-Torres J, Crabb JW and Ghosh S

    Department of Ophthalmology and Visual Science, Yale University School of Medicine, New Haven, Connecticut 06510, USA.

    Purpose: To evaluate the patterns of expression of beta subunit isoforms of the Na+,K(+)-ATPase and H+,K(+)-ATPase in the human eye and to determine the cell-specific distribution of the beta 2 subunit in the human ciliary epithelium.

    Methods: Total RNA extracted from human ocular tissues was screened by Northern blot analysis with cDNA probes for the human Na+,K(+)-ATPase subunit isoforms (beta 1 and beta 2) or the H+,K(+)-ATPase (alpha and beta) subunits. Antibodies were raised to the amino and carboxyl terminal regions of the human beta 2 isoform. Polymerase chain reaction was used to verify the expression of beta 2 subunit in nonpigmented ciliary epithelial cells (NPE).

    Results: Transcripts for the Na+,K(+)-ATPase beta 1 and beta 2 subunit isoforms were present at different levels in all the ocular tissues except the lens, which expressed only beta 1. No transcripts for the alpha or beta subunits of the H+,K(+)-ATPase were detected in the eye. Isoform beta 2 specific anti-peptide antibodies V15E (N-terminus) and A18R (C-terminus) recognized a 55- to 60-kDa protein in the ciliary epithelium and the core protein of 32 kDa after N-glycanase treatment. Immunocytochemical localization within the ciliary epithelium indicates that the Na+,K(+)-ATPase beta 2 isoform is expressed preferentially in the NPE cells. The expression of Na+,K(+)-ATPase beta 2 isoform in the human NPE cell line, ODM-2, was confirmed by polymerase chain reaction amplification and Southern blot analysis.

    Conclusions: The Na+,K(+)-ATPase beta 2 subunit isoform, but not H+,K(+)-ATPase, was expressed widely in ocular tissues of the human eye. The restricted cellular distribution of beta 2 isoform within the NPE cells represents an important differential gene marker associated with the multiple alpha subunit isoforms of Na+,K(+)-ATPase.

    Funded by: NEI NIH HHS: EY00785, EY08672

    Investigative ophthalmology & visual science 1995;36;13;2717-28

  • Characterization and quantification of full-length and truncated Na,K-ATPase alpha 1 and beta 1 RNA transcripts expressed in human retinal pigment epithelium.

    Ruiz A, Bhat SP and Bok D

    Department of Anatomy and Cell Biology, School of Medicine, University of California, Los Angeles 90024, USA.

    We have characterized cDNA clones encoding the alpha 1 and beta 1 subunits of Na,K-ATPase produced in the human retinal pigment epithelium (hRPE). In addition to isolating clones corresponding to known sequences of Na,K-ATPase subunits, we report hitherto unknown forms of Na,K-ATPase with unique deduced amino acid (aa) sequences in their C-termini. Truncated cDNA sequences were found for both the beta 1 and alpha 1 subunits. While the beta 1 sequence is truncated by two aa residues at the C terminus, in the alpha 1 sequence 342 aa have been replaced by a unique sequence containing only 44 aa. Interestingly, this new C-terminal polypeptide shows sequence similarities to the Ca(2+)-ATPase and contains consensus sequence elements for phosphorylation and cell adhesion, suggesting expression of Na,K-ATPase subunits with unique functions. Using reverse transcription-polymerase chain reaction, RNA sequences for alpha 1, beta 1 and their corresponding truncated isoforms were quantified. 4.0 x 10(5) alpha 1 and 2.3 x 10(5) beta 1 molecules were found per ng of mRNA from hRPE. Much lower levels were detected for truncated alpha 1 and beta 1 (3.6 x 10(3) and 2.7 x 10(3) molecules/ng, respectively). These data corroborate the expression of truncated transcripts coding for unique aa sequences in hRPE, and suggest that factors other than alpha 1 and beta 1 mRNA levels regulate the equimolar accumulation of alpha and beta subunits in the plasma membrane.

    Funded by: NEI NIH HHS: EY00331, EY00444, EY06044

    Gene 1995;155;2;179-84

  • Construction of a physical map on mouse and human chromosome 1: comparison of 13 Mb of mouse and 11 Mb of human DNA.

    Oakey RJ, Watson ML and Seldin MF

    Department of Medicine, Duke University Medical Center, Durham, NC 27710.

    Long range restriction site maps of 13 Mb of mouse chromosome 1 and 11 Mb of human chromosome 1 were constructed using a framework provided by a detailed mouse genetic map. Where an unambiguous gene order could be determined in both species (14 genes), the human and mouse orders were identical. In addition, the distances between markers in the mouse and human were similar except for one region of the conserved linkage group where we could detect a larger distance in the mouse compared to the human. These data support the use of comparative mapping in physical map construction and further suggest the value of using mouse genetics to help define human disease loci.

    Funded by: NHGRI NIH HHS: HG00101

    Human molecular genetics 1992;1;8;613-20

  • Molecular genetics of Na,K-ATPase.

    Lingrel JB, Orlowski J, Shull MM and Price EM

    Department of Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati College of Medicine, Ohio 45267.

    Researchers in the past few years have successfully used molecular-genetic approaches to determine the primary structures of several P-type ATPases. The amino-acid sequences of distinct members of this class of ion-transport ATPases (Na,K-, H,K-, and Ca-ATPases) have been deduced by cDNA cloning and sequencing. The Na,K-ATPase belongs to a multiple gene family, the principal diversity apparently resulting from distinct catalytic alpha isoforms. Computer analyses of the hydrophobicity and potential secondary structure of the alpha subunits and primary sequence comparisons with homologs from various species as well as other P-type ATPases have identified common structural features. This has provided the molecular foundation for the design of models and hypotheses aimed at understanding the relationship between structure and function. Development of a hypothetical transmembrane organization for the alpha subunit and application of site-specific mutagenesis techniques have allowed significant progress to be made toward identifying amino acids involved in cardiac glycoside resistance and possibly binding. However, the complex structural and functional features of this protein indicate that extensive research is necessary before a clear understanding of the molecular basis of active cation transport is achieved. This is complicated further by the paucity of information regarding the structural and functional contributions of the beta subunit. Until such information is obtained, the proposed model and functional hypotheses should be considered judiciously. Considerable progress also has been made in characterizing the regulatory complexity involved in expression of multiple alpha-isoform and beta-subunit genes in various tissues and cells during development and in response to hormones and cations. The regulatory mechanisms appear to function at several molecular levels, involving transcriptional, posttranscriptional, translational, and posttranslational processes in a tissue- or cell-specific manner. However, much research is needed to precisely define the contributions of each of these mechanisms. Recent isolation of the genes for these subunits provides the framework for future advances in this area. Continued application of biochemical, biophysical, and molecular genetic techniques is required to provide a detailed understanding of the mechanisms involved in cation transport of this biologically and pharmacologically important enzyme.

    Progress in nucleic acid research and molecular biology 1990;38;37-89

  • Human Na+,K+-ATPase genes. Beta-subunit gene family contains at least one gene and one pseudogene.

    Ushkaryov YuA, Monastyrskaya GS, Broude NE, Nikiforova NN, Bessarab DA, Orlova MYu, Petrukhin KE, Modyanov NN and Sverdlov ED

    Shemyakin Institute of Bioorganic Chemistry, USSR Academy of Sciences, Moscow.

    The existence of a chromosome gene family containing at least one gene and one pseudogene was shown for the Na+,K+-ATPase beta-subunit. A partial structure of the beta 1-gene was determined, the coding part of which was completely homologous to cDNA of the Na+,K+-ATPase beta I-subunit from HeLa cells. The region encoding the putative protein transmembrane domain was shown to be bordered by two introns. The structure of a pseudogene (beta psi) was determined. This pseudogene is processed and contains multiple stop codons. Its homology to the beta I-subunit cDNA from HeLa cells is about 88%.

    FEBS letters 1989;257;2;439-42

  • Characterization of two genes for the human Na,K-ATPase beta subunit.

    Lane LK, Shull MM, Whitmer KR and Lingrel JB

    Department of Molecular Genetics, University of Cincinnati College of Medicine, Ohio 45267.

    A total of 29 human genomic DNA clones that hybridize with cDNAs for the sheep and rat Na,K-ATPase beta subunits have been isolated, classified by restriction endonuclease mapping and Southern blot hybridization analysis, and sequenced. One class of clones, designated ATP1BL1, represents a processed pseudogene for the beta subunit. The second class, designated ATP1B, includes 15 overlapping genomic clones and represents a functional gene for the human Na,K-ATPase beta subunit. ATP1B spans about 26.7 kb of genomic DNA and includes 24 kb of intron sequence. The complete mRNA transcript for the human beta subunit is encoded by six exons, ranging in size from 81 to 1427 bp. Primer extension and S1 nuclease protection experiments with human kidney RNA indicate the presence of two major transcription initiation sites at -510 and -201 to -191, with minor initiation sites at -268, -182 to -174, and -142. The distal initiation site at -510 is preceded by consensus sequences for CAAT and TATA boxes. The DNA sequence preceding the proximal heterogeneous initiation sites contains a CAAT box, but no TATA box. Two of the 12 GC boxes (GGCGGG and CCCGCC) located in the 5' region of ATP1B are located between this CAAT box and the proximal clusters of transcription initiation sites.

    Funded by: NHLBI NIH HHS: P01 HL22619

    Genomics 1989;5;3;445-53

  • Identification of a putative isoform of the Na,K-ATPase beta subunit. Primary structure and tissue-specific expression.

    Martin-Vasallo P, Dackowski W, Emanuel JR and Levenson R

    Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut 06510.

    We have isolated cDNA clones from rat brain and human liver encoding a putative isoform of the Na,K-ATPase beta subunit. The rat brain cDNA contains an open reading frame of 870 nucleotides coding for a protein of 290 amino acids with a calculated molecular weight of 33,412. The corresponding amino acid sequence shows 98% identity with its human liver counterpart. The proteins encoded by the rat and human cDNAs exhibit a high degree of primary sequence and secondary structure similarity with the rat Na,K-ATPase beta subunit. We have therefore termed the polypeptides these cDNAs encode a beta 2 subunit with the previously characterized rat cDNA encoding a beta 1 subunit. Analysis of rat tissue RNA reveals that the beta 2 subunit gene encodes a 3.4-kilobase mRNA which is expressed in a tissue specific fashion distinct from that of rat beta 1 subunit mRNA. Cell lines derived from the rat central nervous system shown to lack beta 1 subunit mRNA sequences were found to express beta 2 subunit mRNA. These results suggest that different members of the Na,K-ATPase beta subunit family may have specialized functions.

    Funded by: NCI NIH HHS: CA-38992; NHLBI NIH HHS: HL-39263

    The Journal of biological chemistry 1989;264;8;4613-8

  • Chromosomal localization of human Na+, K+-ATPase alpha- and beta-subunit genes.

    Yang-Feng TL, Schneider JW, Lindgren V, Shull MM, Benz EJ, Lingrel JB and Francke U

    Department of Human Genetics, Yale University School of Medicine, New Haven, Connecticut 06510.

    Na+, K+-ATPase is a heterodimeric enzyme responsible for the active maintenance of sodium and potassium gradients across the plasma membrane. Recently, cDNAs for several tissue-specific isoforms of the larger catalytic alpha-subunit and the smaller beta-subunit have been cloned. We have hybridized rat brain and human kidney cDNA probes, as well as human genomic isoform-specific DNA fragments, to Southern filters containing panels of rodent X human somatic cell hybrid lines. The results obtained have allowed us to assign the loci for the ubiquitously expressed alpha-chain (ATP1A1) to human chromosome 1, region 1p21----cen, and for the alpha 2 isoform that predominates in neural and muscle tissues (ATP1A2) to chromosome 1, region cen----q32. A common PstI RFLP was detected with the ATP1A2 probe. The alpha 3 gene, which is expressed primarily in neural tissues (ATP1A3), was assigned to human chromosome 19. A fourth alpha gene of unknown function (alpha D) that was isolated by molecular cloning (ATP1AL1) was mapped to chromosome 13. Although evidence to date had suggested a single gene for the beta-subunit, we found hybridizing restriction fragments derived from two different human chromosomes. On the basis of knowledge of conserved linkage groups on human and murine chromosomes, we propose that the coding gene ATP 1B is located on the long arm of human chromosome 1 and that the sequence on human chromosome 4 (ATP 1BL1) is either a related gene or a pseudogene.

    Funded by: NHLBI NIH HHS: HL28573; NIGMS NIH HHS: GM26105, T32GM07439

    Genomics 1988;2;2;128-38

  • Family of Na+,K+-ATPase genes. Intra-individual tissue-specific restriction fragment length polymorphism.

    Sverdlov ED, Broude NE, Sverdlov VE, Monastyrskaya GS, Grishin AV, Petrukhin KE, Akopyanz NS, Modyanov NN and Ovchinnikov YuA

    Intra-individual tissue-specific restriction fragment length polymorphism (RFLP) has been demonstrated in DNA isolated from different mammalian tissues using cDNAs of alpha- and beta-subunits of Na+,K+-ATPase as hybridization probes. We propose that the RFLPs could result from gene rearrangements in the gene loci for the alpha- and beta-subunits of Na+,K+-ATPase. The changes in restriction patterns have been shown to occur during embryonic development and tumor formation. In addition, the tissue specificity of the expression of different genes of the family of Na+,K+-ATPase genes and their low expression in tumor cells have been demonstrated.

    FEBS letters 1987;221;1;129-33

  • Molecular cloning and sequence analysis of human Na,K-ATPase beta-subunit.

    Kawakami K, Nojima H, Ohta T and Nagano K

    We have isolated a cDNA clone for the beta-subunit of HeLa cell Na,K-ATPase, containing a 2208-base-pair cDNA insert covering the whole coding region of the beta-subunit. Nucleotide sequence analysis revealed that the amino acid sequence of human Na,K-ATPase exhibited 61% homology with that of Torpedo counterpart (Noguchi et al. (1986) FEBS Lett. in press). A remarkable conservation in the nucleotide sequence of the 3' non-coding region was detected between the human and Torpedo cDNAs. RNA blot hybridization analysis revealed the presence of two mRNA species in HeLa cells. S1 nuclease mapping indicated that they were derived from utilization of two distinct polyadenylation signals in vivo. Total genomic Southern hybridization indicated the existence of only a few, possibly one set of gene encoding the Na,K-ATPase beta-subunit in the human genome.

    Nucleic acids research 1986;14;7;2833-44

Gene lists (10)

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
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
L00000013 G2C Homo sapiens Human mGluR5 Human orthologues of mouse mGluR5 complex adapted from Collins et al (2006) 52
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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