Transcriptional Regulation of Human Dual Specificity Protein Phosphatase 1 (DUSP1) Gene by Glucocorticoids Lauren E. Shipp1, Joyce V. Lee1, Chi-Yi Yu 1 , Miles Pufall2, Pili Zhang 3 , Donald K. Scott3, Jen-Chywan 1 Wang * 1 Department of Nutritional Science and Toxicology, University of California, Berkeley, California, United States of America, 2 Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, California, United States of America, 3 Division of Endocrinology, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America Abstract Background: Glucocorticoids are potent anti-inflammatory agents commonly used to treat inflammatory diseases. They convey signals through the intracellular glucocorticoid receptor (GR), which upon binding to ligands, associates with genomic glucocorticoid response elements (GREs) to regulate transcription of associated genes. One mechanism by which glucocorticoids inhibit inflammation is through induction of the dual specificity phosphatase-1 (DUSP1, a.k.a. mitogen- activated protein kinase phosphatase-1, MKP-1) gene. Methodology/Principal Findings: We found that glucocorticoids rapidly increased transcription of DUSP1 within 10 minutes in A549 human lung adenocarcinoma cells. Using chromatin immunoprecipitation (ChIP) scanning, we located a GR binding region between 21421 and 21118 upstream of the DUSP1 transcription start site. This region is active in a reporter system, and mutagenesis analyses identified a functional GRE located between 21337 and 21323. We found that glucocorticoids increased DNase I hypersensitivity, reduced nucleosome density, and increased histone H3 and H4 acetylation within genomic regions surrounding the GRE. ChIP experiments showed that p300 was recruited to the DUSP1 GRE, and RNA interference experiments demonstrated that reduction of p300 decreased glucocorticoid-stimulated DUSP1 gene expression and histone H3 hyperacetylation. Furthermore, overexpression of p300 potentiated glucocorticoid- stimulated activity of a reporter gene containing the DUSP1 GRE, and this coactivation effect was compromised when the histone acetyltransferase domain was mutated. ChIP-reChIP experiments using GR followed by p300 antibodies showed significant enrichment of the DUSP1 GRE upon glucocorticoid treatment, suggesting that GR and p300 are in the same protein complex recruited to the DUSP1 GRE. Conclusions/Significance: Our studies identified a functional GRE for the DUSP1 gene. Moreover, the transcriptional activation of DUSP1 by glucocorticoids requires p300 and a rapid modification of the chromatin structure surrounding the GRE. Overall, understanding the mechanism of glucocorticoid-induced DUSP1 gene transcription could provide insights into therapeutic approaches against inflammatory diseases. Citation: Shipp LE, Lee JV, Yu C-Y, Pufall M, Zhang P, et al. (2010) Transcriptional Regulation of Human Dual Specificity Protein Phosphatase 1 (DUSP1) Gene by Glucocorticoids. PLoS ONE 5(10): e13754. doi:10.1371/journal.pone.0013754 Editor: Melanie Koenigshoff, Comprehensive Pneumology Center, Germany Received January 25, 2010; Accepted October 11, 2010; Published October 29, 2010 Copyright: 2010 Shipp et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Funding: This study is supported by a New Investigator Award (17KT-0028) from University of California Tobacco-related Diseases Research Program. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: The authors have declared that no competing interests exist. * E-mail: walwang@berkeley.edu Introduction Glucocorticoids are steroid hormones that exhibit potent anti- inflammatory effects through two main mechanisms. First, they inhibit the transcription of proinflammatory genes, such as cytokines, chemokines, and adhesion molecules via suppression of the transcriptional activation induced by AP-1 and NFkB [1,2,3,4,5]. Second, they induce genes that antagonize the inflammatory response, including the glucocorticoid-induced leucine zipper (GILZ) and dual specificity phosphatase-1 (DUSP1, a.k.a. mitogen-activated protein kinase phosphatase-1, MKP-1, Entrez GeneID: 1843) [6]. DUSP1 opposes the inflammatory response by blocking crucial signaling pathways. DUSP1 is a member of a large family of multifunctional phosphatases that resides in the nucleus and specifically dephosphorylates and inactivates members of the MAPK family, such as JNK, p38 MAPK, and ERK [7,8]. These MAPKs play important roles in the stimulation of the inflamma- tory response by increasing the expression of many proinflamma- tory mediators [9,10]. For example, cytokines, such as tumor necrosis factor a (TNF-a) and interleukin-1b (IL-1b), and endotoxins, such as lipopolysaccharides, have been shown to activate p38 MAPK, which in turn phosphorylates and activates downstream MAPKAP kinase 2 (MK2) [11,12]. MK2 then phosphorylates and inactivates ZFP36 (also known as tristetrapro- lin, TTP). ZFP36 destabilizes the mRNA of many proinflamma- tory genes by binding to an AU-rich element (ARE) located at the 39 untranslated region (UTR) of their mRNA [11,12]. Increased PLoS ONE | www.plosone.org 1 October 2010 | Volume 5 | Issue 10 | e13754