title: TRE-dependent transcription activation by JDP2-CHOP10 association.
abstract: The c-Jun dimerization protein 2, JDP2, is a member of the activating protein 1 (AP-1) family of transcription factors. Overexpression of JDP2 has been shown to result in repression of AP-1-dependent transcription and inhibition of cellular transformation. Other studies suggested that JDP2 may function as an oncogene. Here we describe the identification of CHOP10, a member of the CCAAT enhancer binding proteins, as a protein associating with JDP2. In contrast to the inhibition of transcription by JDP2, JDP2-CHOP complex strongly enhances transcription from promoters containing TPA response elements (TRE), but not from those containing cyclic AMP response elements (CRE). The association between JDP2 and CHOP10 involves the leucine zipper motifs of both proteins, whereas, the basic domain of CHOP10 contributes to the association of the JDP2-CHOP10 complex with the DNA. DNA binding of JDP2-CHOP complex is observed both in vitro and in vivo. Finally, overexpression of JDP2 results in increased cell viability following ER stress and counteracts CHOP10 pro-apoptotic activity. JDP2 expression may determine the threshold for cell sensitivity to ER stress. This is the first report describing TRE-dependent activation of transcription by JDP2 and thus may provide an explanation for the as yet unexplored oncogenic properties of JDP2.
authors.affiliation: Department of Molecular Genetics, The Rappaport Family Institute for Research in the Medical Sciences, Technion-Israel Institute of Technology, 1 Efron St. Bat-Galim, Haifa 31096, Israel.
authors.forename: Keren
authors.initials: K
authors.lastname: Weidenfeld-Baranboim
authors.forename: Keren
authors.initials: K
authors.lastname: Bitton-Worms
authors.forename: Ami
authors.initials: A
authors.lastname: Aronheim
mesh_terms: D000818:Animals; D004247:DNA / Q000378:metabolism; D004721:Endoplasmic Reticulum / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D047468:Immunoprecipitation; D051379:Mice; D041681:NIH 3T3 Cells; D017434:Protein Structure, Tertiary; D016283:Proto-Oncogene Proteins p21(ras) / Q000378:metabolism; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D020218:Response Elements; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D051742:Transcription Factor CHOP / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015533:Transcriptional Activation; D020798:Two-Hybrid System Techniques
chemical_list: C497249:DDIT3 protein, human; C106160:Jdp2 protein, rat; D011993:Recombinant Fusion Proteins; D012097:Repressor Proteins; D051742:Transcription Factor CHOP; D004247:DNA; D016283:Proto-Oncogene Proteins p21(ras); D013755:Tetradecanoylphorbol Acetate