HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

J. Biol. Chem., Vol. 278, Issue 22, 19986-19994, May 30, 2003

This Article Full Text Full Text (PDF) All Versions of this Article: 278/22/19986    most recent M207983200v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Mahapatra, N. R. Articles by Mahata, S. K. Search for Related Content PubMed PubMed Citation Articles by Mahapatra, N. R. Articles by Mahata, S. K. Social Bookmarking                      What's this?

Secretin Activation of Chromogranin A Gene Transcription

IDENTIFICATION OF THE SIGNALING PATHWAYS IN CIS AND IN TRANS^*

Nitish R. Mahapatra, Manjula Mahata, Daniel T. O'Connor and Sushil K. Mahata 

From the Department of Medicine and Center for Molecular Genetics, University of California San Diego, La Jolla, California 92093 and the San Diego Veterans Affairs Healthcare System, San Diego, California 92161

Secretin evokes catecholamine secretion from PC12 pheochromocytoma cells. We tested whether secretin activates transcription of the major vesicular core protein chromogranin A (CgA). Secretin stimulated both endogenous CgA gene transcription (4–6-fold) as well as transfected CgA promoter activity (8–10-fold; EC₅₀, 7 nM) in PC12 cells. Studies on CgA promoter 5'-deletion mutant/luciferase reporter constructs, point mutations of the CgA cAMP response element (CRE), and their transfer to a heterologous promoter implicated CRE in cis as both necessary and sufficient for secretin-stimulated CgA gene transcription. Secretin-induced CgA gene transcription was inhibited/abolished by cytosolic Ca²⁺ chelation, chemical blockade of phospholipase C, protein kinase A (PKA), or mitogen-activated protein (MAP) kinase extracellular signal regulated kinase (ERK) 1/2 and the expression of dominant negative mutants of ERK1/2, CRE binding protein (CREB) kinase RSK2, or CREB. Secretin also augmented (4-fold) phosphorylation of ERK1/2. Trans-activation (21-fold) of GAL4-CREB fusion protein by secretin indicates involvement of CREB in secretin signaling to gene transcription. Electrophoretic mobility shift assays also identified CREB as the mediator of secretin-induced CgA gene transcription, and pCREB supershifts indicated Ser-133 as the active CREB moiety in vitro. This conclusion was reinforced in vivo by results of chromatin pCREB immunoprecipitation assays. We conclude that secretin signals to CgA gene transcription through the CRE domain in cis and through cAMP, Ca²⁺, PKA, MAP kinase, and the transcription factor CREB in trans. Thus, multiple signal transduction pathways seem to subserve the function of stimulus-transcription coupling after this peptidergic stimulus to chromaffin cells.

Received for publication, August 5, 2002 , and in revised form, March 12, 2003.

^* This work was supported by grants from the Department of Veterans Affairs and National Institutes of Health Grants DA11311 and HL69758 (to S. K. M.) and HL55583, HL58120, HL69758, and DK60702 (to D. T. O.). The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

To whom correspondence should be addressed: Dept. of Medicine (0838), University of California, San Diego, 9500 Gilman Dr., La Jolla, CA 92093-0838. Tel.: 858-552-8585 (ext. 2637); Fax 858-642-6425; E-mail: smahata{at}ucsd.edu.

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				J.Y.S. CHU, W.H. YUNG, and B.K.C. CHOW Secretin: A Pleiotrophic Hormone Ann. N.Y. Acad. Sci., July 1, 2006; 1070(1): 27 - 50. [Abstract] [Full Text] [PDF]

				T. Kim, M. C. Gondre-Lewis, I. Arnaoutova, and Y. P. Loh Dense-Core Secretory Granule Biogenesis Physiology, April 1, 2006; 21(2): 124 - 133. [Abstract] [Full Text] [PDF]

				S. K. Mahata, M. Mahata, G. Wen, W. B. Wong, N. R. Mahapatra, B. A. Hamilton, and D. T. O'Connor The Catecholamine Release-Inhibitory "Catestatin" Fragment of Chromogranin A: Naturally Occurring Human Variants with Different Potencies for Multiple Chromaffin Cell Nicotinic Cholinergic Responses Mol. Pharmacol., November 1, 2004; 66(5): 1180 - 1191. [Abstract] [Full Text] [PDF]