Regulation of reconstituted renal Na+/H+ exchanger by calcium-dependent protein kinases.
Journal Article (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
International Standard Serial Number (ISSN)
- 0022-2631
Digital Object Identifier (DOI)
- 10.1007/BF01993983
Language
- eng
Conference Location
- United States