Faculty Articles

Title

Renal expression of the gene encoding the gastric H(+)-K(+)-ATPase beta-subunit.

ISBN or ISSN

0002-9513

Publication Title

The American journal of physiology

Volume

268

Issue

3 Pt 2

Publication Date / Copyright Date

3-1-1995

First Page

363

Last Page

374

Publisher

American Physiological Society

DOI Number

10.1152/ajprenal.1995.268.3.F363

Abstract

The gastric mucosal parietal cells and cells of the renal collecting duct both possess H(+)-K(+)-adenosinetriphosphatase (H(+)-K(+)-ATPase) activities. In the stomach, the H(+)-K(+)-ATPase (EC 3.6.1.3) is responsible for acidification of luminal contents. The kidney H(+)-K(+)-ATPase protein(s) contribute to potassium reabsorption and secretion of hydrogen ions to maintain potassium and acid-base homeostasis. The stomach H(+)-K(+)-ATPase is well defined and consists of an alpha-catalytic subunit of apparent molecular mass of 95 kDa and a highly glycosylated beta-subunit of 60-90 kDa. The molecular identity of the protein that mediates the H(+)-K(+)-ATPase activity in the kidney has been addressed in this paper. A combination of RNA hybridizations, polymerase chain reaction analysis of kidney RNA, and sequence analysis of cDNAs indicated that gastric H(+)-K(+)-ATPase beta-subunit mRNA is present in kidney. Immunoblotting with antibodies specific for the gastric H(+)-K(+)-ATPase beta-subunit detected proteins, which, after deglycosylation, had the same molecular mass as the gastric beta-subunit in membrane protein preparations from rabbit, pig, rat, and mouse kidneys. Furthermore, we have used transgenic mice to demonstrate that the gastric H(+)-K(+)-ATPase beta-subunit gene contains cis-acting regulatory sequences that are active in both gastric parietal cells and the renal collecting ducts. Overall, these data indicate that the gastric H(+)-K(+)-ATPase beta-subunit is found in the kidney and probably associates with the gastric H(+)-K(+)-ATPase alpha-subunit and/or other P-type ATPase alpha-subunits, thus contributing to acid-base and potassium homeostasis.

Disciplines

Medical Specialties | Medicine and Health Sciences | Osteopathic Medicine and Osteopathy

Keywords

Animals, Antibodies, Monoclonal, Base Sequence, DNA, Complementary, Gastric Mucosa, Gene Expression, Genes, Regulator, H(+)-K(+)-Exchanging ATPase, Immunohistochemistry, Kidney, Mice, Mice, Transgenic, Molecular Sequence Data, Polymerase Chain Reaction, Protein Conformation, RNA, Messenger, Rabbits, Swine

Peer Reviewed

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