Faculty Collaboration Database

The effect of tyrosine nitration of L-type Ca2+ channels on excitation-transcription coupling in colonic inflammation. Br J Pharmacol 2010 Mar;159(6):1226-35

Date

02/05/2010

Pubmed ID

20128810

Pubmed Central ID

PMC2848927

DOI

10.1111/j.1476-5381.2009.00599.x

Scopus ID

2-s2.0-77949386273 (requires institutional sign-in at Scopus site)   18 Citations

Abstract

BACKGROUND AND PURPOSE: 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.

EXPERIMENTAL APPROACH: CREB and phospho-CREB were detected by Western blots and CRE activation measured by dual luciferase assay. Chinese hamster ovary (CHO) cells were transfected with hCa(v)1.2b and hCa(v)1.2b c-terminal mutants. Colonic inflammation was induced by intracolonic instillation of 2,4,6 trinitrobenzene sulphonic acid in mouse colon.

KEY RESULTS: In hCa(v)1.2b transfected CHO cells and in native colonic smooth muscle, depolarization with 80 mM KCl induced CREB phosphorylation (pCREB). Treatment with peroxynitrite inhibited KCl-induced pCREB. Following experimental colitis, KCl-induced CREB phosphorylation was abolished in smooth muscle, concomitant with tyrosine nitration of Ca(2+) channels. Depolarization increased CRE activation in hCa(v)1.2b CHO cells by 2.35 fold which was blocked by nifedipine and by protein nitration of Ca(2+) channels with peroxynitrite. The Src-kinase inhibitor, PP2, blocked depolarization-induced CRE activation. Mutation of the C-terminus tyrosine residue, Y2134F, but not Y1861F, blocked CRE activation.

CONCLUSIONS AND IMPLICATIONS: Post-translational modification of Ca(2+) channels due to tyrosine nitration modified excitation-transcriptional coupling in colonic inflammation.

Author List

Kang M, Ross GR, Akbarali HI

Author

Gracious R. Ross Research Scientist II in the Cardiovascular Center department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Animals
Blotting, Western
CHO Cells
Calcium Channels, L-Type
Colitis
Cricetinae
Cricetulus
Cyclic AMP Response Element-Binding Protein
Disease Models, Animal
Excitation Contraction Coupling
Humans
Immunohistochemistry
Immunoprecipitation
Male
Membrane Potentials
Mice
Mice, Inbred BALB C
Muscle, Smooth
Patch-Clamp Techniques
Peroxynitrous Acid
Protein Kinase Inhibitors
Response Elements
Reverse Transcriptase Polymerase Chain Reaction
Transcriptional Activation
Transfection
Tyrosine
src-Family Kinases