alpha 4, a unique kidney-specific isoform of mouse vacuolar H+-ATPase subunit a

Citation
T. Oka et al., alpha 4, a unique kidney-specific isoform of mouse vacuolar H+-ATPase subunit a, J BIOL CHEM, 276(43), 2001, pp. 40050-40054
Citations number
37
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Biochemistry & Biophysics
Journal title
JOURNAL OF BIOLOGICAL CHEMISTRY
ISSN journal
0021-9258 → ACNP
Volume
276
Issue
43
Year of publication
2001
Pages
40050 - 40054
Database
ISI
SICI code
0021-9258(20011026)276:43<40050:A4AUKI>2.0.ZU;2-F
Abstract
The vacuolar-type H+-ATPase (V-ATPase) translocates protons across membrane s. Here, we have identified a mouse cDNA coding for a fourth isoform (a4) o f the membrane sector subunit a of V-ATPase. This isoform was specifically expressed in kidney, but not in the heart, brain, spleen, lung, liver, musc le, or testis. Immunoprecipitation experiments, together with sequence simi larities for other isoforms (a1, a2, and a3), indicate that the a4 isoform is a component of V-ATPase. Moreover, histochemical studies show that a4 is localized in the apical and basolateral plasma membranes of cortical alpha - and beta -intercalated cells, respectively. These results suggest that th e V-ATPase, with the a4 isoform, is important for renal acid/base homeostas is.