Protein kinase C phosphorylates the 'a' forms of plasma membrane Ca2+ pump isoforms 2 and 3 and prevents binding of calmodulin

Agnes Enyedi, Nancy L. Elwess, Adelaida G. Filoteo, Anil K. Verma, Katalin Paszty, John T. Penniston

Research output: Article

54 Citations (Scopus)

Abstract

Phosphorylation by protein kinase C of the 'a' and 'b' variants of plasma membrane Ca2+ pump isoforms 2 and 3 was studied. Full-length versions of these isoforms were assembled and expressed in COS cells. Whereas the 'a' forms were phosphorylated easily with PKC, isoform 2b was phosphorylated only a little, and isoform 3b was not phosphorylated at all. Phosphorylation of isoforms 2a and 3a did not affect their basal activity, but prevented the stimulation of their activity by calmodulin and their binding to calmodulin-Sepharose. This indicated that phosphorylation prevented activation of these isoforms by preventing calmodulin binding. Based on these results, phosphorylation of the pump with PKC would be expected to increase free intracellular Ca2+ levels in those cells where isoforms 2a and 3a are expressed.

Original languageEnglish
Pages (from-to)27525-27528
Number of pages4
JournalJournal of Biological Chemistry
Volume272
Issue number44
DOIs
Publication statusPublished - okt. 31 1997

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Cell Biology

Fingerprint Dive into the research topics of 'Protein kinase C phosphorylates the 'a' forms of plasma membrane Ca<sup>2+</sup> pump isoforms 2 and 3 and prevents binding of calmodulin'. Together they form a unique fingerprint.

  • Cite this