The effect of tyrosine nitration of L-type Ca2+ channels on excitation-transcription coupling in colonic inflammation.

Abstract

Excitation-transcriptional coupling involves communication between plasma membrane ion channels and gene expression in the nucleus. Calcium influx through L-type Ca(2+) channels induces phosphorylation of the transcription factor, cyclic-AMP response element binding protein (CREB) and downstream activation of the cyclic-AMP response element (CRE) promoter regions. Tyrosine nitration of Ca(2+) channels attenuates interactions with c-Src kinase, decreasing Ca(2+) channel currents and smooth muscle contraction during colonic inflammation. In this study we examined the effect of tyrosine nitration and colonic inflammation on Ca(2+) channel mediated phosphorylation of CREB and CRE activation.