Phosphorylation of Na,K-ATPase alpha-subunits in microsomes and in homogenates of Xenopus oocytes resulting from the stimulation of protein kinase A and protein kinase C.

Details

Serval ID
serval:BIB_322BE950BC64
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Phosphorylation of Na,K-ATPase alpha-subunits in microsomes and in homogenates of Xenopus oocytes resulting from the stimulation of protein kinase A and protein kinase C.
Journal
Journal of Biological Chemistry
Author(s)
Chibalin A.V., Vasilets L.A., Hennekes H., Pralong D., Geering K.
ISSN
0021-9258
Publication state
Published
Issued date
11/1992
Peer-reviewed
Oui
Volume
267
Number
31
Pages
22378-22384
Language
english
Notes
Publication types: In Vitro ; Journal Article
Abstract
The phosphorylation of the alpha-subunit of Na+/K(+)-transporting ATPase (Na,K-ATPase) by cAMP-dependent protein kinase (PKA) and protein kinase C (PKC) was characterized in purified enzyme preparations of Bufo marinus kidney and duck salt gland and in microsomes of Xenopus oocytes. In addition, we have examined cAMP and phorbol esters, which are stimulators of PKA and PKC, respectively, for their ability to provoke the phosphorylation of alpha-subunits of Na,K-ATPase in homogenates of Xenopus oocytes. In the enzyme from the duct salt gland, phosphorylation by PKA and PKC occurs on serine and threonine residues, whereas in the enzyme from B. marinus kidney and Xenopus oocytes, phosphorylation by PKA occurs only on serine residues. Phosphopeptide analysis indicates that a site phosphorylated by PKA resides in a 12-kDa fragment comprising the C terminus of the polypeptide. Studies of phosphorylation performed on homogenates of Xenopus oocytes show that not only endogenous oocyte Na,K-ATPase but also exogenous Xenopus Na,K-ATPase expressed in the oocyte by microinjection of cRNA can be phosphorylated in response to stimulation of oocyte PKA and PKC. In conclusion, these data are consistent with the possibility that the alpha-subunit of Na,K-ATPase can serve as a substrate for PKA and PKC in vivo.
Keywords
Animals, Bufo marinus, Ducks, Enzyme Activation, Kidney/enzymology, Microsomes/enzymology, Oocytes/enzymology, Phosphorylation, Protein Kinase C/metabolism, Protein Kinases/metabolism, Salt Gland/enzymology, Sodium-Potassium-Exchanging ATPase/metabolism, Xenopus laevis
Pubmed
Web of science
Create date
24/01/2008 13:28
Last modification date
20/08/2019 14:17
Usage data