Regulation of reconstituted renal Na+/H+ exchanger by calcium-dependent protein kinases.

Published

Journal Article

Studies were performed to determine the effect of protein phosphorylation mediated by calcium-calmodulin-dependent multifunctional protein kinase II and calcium-phospholipid-dependent protein kinase on Na+/H+ exchange activity. Proteins from the apical membrane of the proximal tubule of the rabbit kidney were solubilized in octyl glucoside and incubated in phosphorylating solutions containing the protein kinase. 22Na+ uptake was determined subsequently after reconstitution of the proteins into proteoliposomes. Calcium-calmodulin-dependent multifunction protein kinase II inhibited the amiloride-sensitive component of proton gradient-stimulated Na+ uptake in a dose-dependent manner. The inhibitory effect of this kinase had an absolute requirement for calmodulin, Ca2+, and ATP. Calcium-phospholipid-dependent protein kinase stimulated the amiloride-sensitive component of proton gradient-stimulated Na+ uptake in a dose-dependent manner. The stimulating effect of this kinase had an absolute requirement for ATP, Ca2+, and an active phorbol ester. These experiments indicate that Na+/H+ exchange activity of proteoliposomes reconstituted with proteins from renal brush-border membranes are inhibited by protein phosphorylation mediated by calcium-calmodulin-dependent multifunctional protein kinase II and stimulated by that mediated by calcium-calmodulin-dependent protein kinase.

Full Text

Duke Authors

Cited Authors

  • Weinman, EJ; Dubinsky, WP; Fisher, K; Steplock, D; Dinh, Q; Chang, L; Shenolikar, S

Published Date

  • August 1988

Published In

Volume / Issue

  • 103 / 3

Start / End Page

  • 237 - 244

PubMed ID

  • 2846848

Pubmed Central ID

  • 2846848

International Standard Serial Number (ISSN)

  • 0022-2631

Language

  • eng

Conference Location

  • United States