Referenced in: none

Automatically associated channels: Cav1.3

Title: Protein kinase C activation inhibits Cav1.3 calcium channel at NH2-terminal serine 81 phosphorylation site.

Authors: Ghayath Baroudi, Yongxia Qu, Omar Ramadan, Mohamed Chahine, Mohamed Boutjdir

Journal, date & volume: Am. J. Physiol. Heart Circ. Physiol., 2006 Oct , 291, H1614-22

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/16973824

Abstract
The Ca(v)1.3 (alpha(1D)) variant of L-type Ca(2+) channels plays a vital role in the function of neuroendocrine and cardiovascular systems. In this article, we report on the molecular and functional basis of alpha(1D) Ca(2+) channel modulation by protein kinase C (PKC). Specifically, we show that the serine 81 (S81) phosphorylation site at the NH(2)-terminal region plays a critical role in alpha(1D) Ca(2+) channel modulation by PKC. The introduction of a negatively charged residue at position 81, by converting serine to aspartate, mimicked the PKC phosphorylation effect on alpha(1D) Ca(2+) channel. The modulation of alpha(1D) Ca(2+) channel by PKC was prevented by dialyzing cells with a 35-amino acid peptide mimicking the alpha(1D) NH(2)-terminal region comprising S81. In addition, the data revealed that only betaII- and epsilonPKC isozymes are implicated in this regulation. These novel findings have significant implications in the pathophysiology of alpha(1D) Ca(2+) channel and in the development of PKC isozyme-targeted therapeutics.