title: STAT4 is required for interleukin-12-induced chromatin remodeling of the CD25 locus.
abstract: Signal transducer and activator of transcription 4 (STAT4) is a critical mediator of interleukin-12 (IL-12)-stimulated inflammatory immune responses. Despite extensive analysis of the immune responses of STAT4-deficient mice, there is still very little understood about STAT4-dependent gene induction. IL-12 stimulated increases in IL-2 receptor alpha chain gene (CD25) mRNA levels and surface expression require STAT4. In this report, we utilize chromatin immunoprecipitation assays to analyze IL-12-stimulated and STAT4-dependent changes in chromatin remodeling of the CD25 gene. Gene activation requires binding of STAT4 to the PRRIII upstream regulatory element, the recruitment of the CREB-binding protein (CBP), and chromatin remodeling including increased acetylation and decreased methylation of histones within the CD25 promoter. Evidence suggests that STAT4 also facilitates binding of other factors to the CD25 promoter including c-Jun. Thus, these results provide a model for STAT4-dependent gene induction and a mechanism for cytokine-induced expression of the CD25 gene.
authors.affiliation: Department of Microbiology and Immunology and the Walther Oncology Center, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA.
authors.forename: Audrey
authors.initials: A
authors.lastname: O'Sullivan
authors.forename: Hua-Chen
authors.initials: HC
authors.lastname: Chang
authors.forename: Qing
authors.initials: Q
authors.lastname: Yu
authors.forename: Mark H
authors.initials: MH
authors.lastname: Kaplan
mesh_terms: D000818:Animals; D015152:Blotting, Northern; D050882:CREB-Binding Protein; D002462:Cell Membrane / Q000378:metabolism; D002469:Cell Separation; D002843:Chromatin / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism / Q000502:physiology*; D005434:Flow Cytometry; D006657:Histones / Q000378:metabolism; D018664:Interleukin-12 / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D008954:Models, Biological; D009687:Nuclear Proteins / Q000378:metabolism; D016133:Polymerase Chain Reaction; D011233:Precipitin Tests; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D012333:RNA, Messenger / Q000378:metabolism; D015375:Receptors, Interleukin-2 / Q000096:biosynthesis*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D050797:STAT4 Transcription Factor; D013154:Spleen / Q000166:cytology; D013997:Time Factors; D015534:Trans-Activators / Q000378:metabolism / Q000502:physiology*; D014158:Transcription, Genetic
chemical_list: D002843:Chromatin; D004268:DNA-Binding Proteins; D006657:Histones; D009687:Nuclear Proteins; D012333:RNA, Messenger; D015375:Receptors, Interleukin-2; D050797:STAT4 Transcription Factor; C494091:Stat4 protein, mouse; D015534:Trans-Activators; D018664:Interleukin-12; D050882:CREB-Binding Protein; C494364:Crebbp protein, mouse