TY - JOUR AU - Feramisco, J R AB - Expression of a peptide inhibitor of protein phosphatase 1 increases phosphorylation and activity of CREB in NIH 3T3 fibroblasts. A S Alberts , M Montminy , S Shenolikar and J R Feramisco Department of Pharmacology, University of California at San Diego, La Jolla 92093-0636. ABSTRACT We have examined the activity and phosphorylation state of the cyclic AMP (cAMP) response element binding factor (CREB) in intact NIH 3T3 cells following microinjection of expression plasmids encoding regulatory proteins of type 1 (PP1) and 2A (PP2A) serine/threonine-specific protein phosphatases. Changes in CREB phosphorylation in the injected cells were monitored by indirect immunofluorescence using an affinity-purified antiserum (Ab5322) which specifically recognizes CREB phosphorylated at Ser-133, and changes in transcriptional activity of CREB were monitored by expression of a reporter gene regulated by cAMP. cAMP-stimulated phosphorylation in NIH 3T3 cells is normally transient, and as expected, after stimulation of cells with cell-permeable cAMP analogs, the level of phosphorylated CREB was found to initially increase and then return to a basal level within 4 h. Microinjection of an expression vector encoding a constitutively active form of inhibitor 1 (I-1), a PP1-specific inhibitor, by itself resulted in an apparent increase in phosphorylated CREB in unstimulated cells. Moreover, injection of the I-1 vector resulted in the prolonged appearance of phosphorylated CREB in cells after cAMP stimulation. In contrast, injection of a plasmid encoding simian virus 40 small t antigen, which interacts with PP2A to inhibit its activity towards several phosphoprotein substrates, had no effect on the phosphorylation state of CREB in stimulated or unstimulated NIH 3T3 cells. Consistent with these results, injection of the I-1 expression vector activated expression from a coinjected CRE-lacZ reporter plasmid, indicating that the increased phosphorylation of CREB also activated its transcriptional activity. These results provide further evidence for a role of a PP1 as the primary protein (Ser/Thr) phosphatase regulating the dephosphorylation of Ser-133 and thereby limiting the transcriptional activity of CREB. CiteULike Connotea Delicious Digg Facebook Google+ Mendeley Reddit StumbleUpon Twitter What's this? « Previous | Next Article » Table of Contents This Article doi: 10.1128/​MCB.14.7.4398 Mol. Cell. Biol. July 1994 vol. 14 no. 7 4398-4407 » Abstract PDF Classifications Research Article Services Email this article to a colleague Similar articles in ASM journals Alert me when this article is cited Alert me if a correction is posted Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of MCB Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Load citing article information Citing articles via Web of Science Citing articles via Google Scholar Google Scholar Articles by Alberts, A. S. Articles by Feramisco, J. R. Search for related content PubMed PubMed citation Articles by Alberts, A. S. Articles by Feramisco, J. R. Related Content Load related web page information Social Bookmarking CiteULike Connotea Delicious Digg Facebook Google+ Mendeley Reddit StumbleUpon Twitter What's this? current issue January 2012, volume 32, issue 1 Spotlights in the Current Issue Architecture of the Yeast RNA Polymerase II Open Complex State and Regulation by TFIIF GATA-1 Establishes Cell-Type-Specific Autophagy as a Developmental Program Prickle Phosphorylation Regulates Its Localization and β-Catenin-Independent Wnt Signaling Alert me to new issues of MCB About MCB Subscribers Authors Reviewers Advertisers Inquiries from the Press Permissions & Commercial Reprints ASM Journals Public Access Policy MCB RSS Feeds 1752 N Street N.W. • Washington DC 20036 202.737.3600 • 202.942.9355 fax • journals@asmusa.org Print ISSN: 0270-7306 Online ISSN: 1098-5549 Copyright © 2011 by the American Society for Microbiology. For an alternate route to MCB .asm.org, visit: http://intl- MCB .asm.org | More Info» var gaJsHost = (("https:" == document.location.protocol) ? "https://ssl." : "http://www."); document.write(unescape("%3Cscript src='" + gaJsHost + "google-analytics.com/ga.js' type='text/javascript'%3E%3C/script%3E")); var pageTracker = _gat._getTracker("UA-5821458-11"); pageTracker._trackPageview(); TI - Expression of a peptide inhibitor of protein phosphatase 1 increases phosphorylation and activity of CREB in NIH 3T3 fibroblasts. JF - Molecular and Cellular Biology DO - 10.1128/MCB.14.7.4398 DA - 1994-07-01 UR - https://www.deepdyve.com/lp/american-society-for-microbiology/expression-of-a-peptide-inhibitor-of-protein-phosphatase-1-increases-4cjpggze5Z SP - 4398 VL - 14 IS - 7 DP - DeepDyve ER -