Molecular cloning and characterization of Atp6v1b1, the murine vacuolar H+ -ATPase B1-subunit.
The multisubunit vacuolar-type proton-translocating ATPases (H(+)-ATPases) mediate the acidification of various intracellular organelles. In a subset of tissues, they also mediate H(+) secretion at the plasma membrane. Two isoforms of the H(+)-ATPase B-subunit exist in humans; we have shown that mutations in ATP6V1B1, encoding the B1-isoform, cause the clinical condition distal renal tubular acidosis. Here we report the cloning and characterization of murine Atp6v1b1, which encodes a 513-amino acid (aa) protein with 93% identity to human ATP6V1B1. Genomic organization is conserved between the murine and human H(+)-ATPase B1-subunits, and Atp6v1b1 maps to a region of mouse chromosome 6 syntenic to human 2p13, the location of ATP6V1B1. Northern blotting detects a 2.2-kb Atp6v1b1 transcript in the kidney and testis, but not other major organs. In mouse kidney, the B1-subunit localizes to intercalated cells of the cortical and medullary collecting duct. B1 protein levels were not increased in either mouse renal cortex or medulla after either 2 or 7 days of oral acid loading. These results demonstrate that Atp6v1b1 encodes the murine ortholog of human ATP6V1B1 and provides a tool for future development of animal models based on manipulation of the Atp6v1b1 genomic locus.
Finberg
Karin E
KE
Department of Genetics, Yale University School of Medicine, New Haven, CT 06520-8005, USA.
Wagner
Carsten A
CA
Stehberger
Paul A
PA
Geibel
John P
JP
Lifton
Richard P
RP
D024506:5' Flanking Region / Q000235:genetics; D000595:Amino Acid Sequence; D000818:Animals; D000918:Antibody Specificity; D001483:Base Sequence; D003001:Cloning, Molecular; D004247:DNA / Q000737:chemistry / Q000235:genetics; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D004822:Epididymis / Q000201:enzymology; D015971:Gene Expression Regulation, Enzymologic; D006801:Humans; D007106:Immune Sera / Q000276:immunology; D007150:Immunohistochemistry; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism; D007668:Kidney / Q000201:enzymology; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D008969:Molecular Sequence Data; D010802:Phylogeny; D021122:Protein Subunits / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid; D025262:Vacuolar Proton-Translocating ATPases / Q000235:genetics* / Q000378:metabolism
D018076:DNA, Complementary; D007106:Immune Sera; D007527:Isoenzymes; D021122:Protein Subunits; D012333:RNA, Messenger; D004247:DNA; C480628:Atp6v1b1 protein, mouse; D025262:Vacuolar Proton-Translocating ATPases