Molecular cloning and characterization of CAPER, a novel coactivator of activating protein-1 and estrogen receptors.
Transcriptional coactivators either bridge transcription factors and the components of the basal transcription apparatus and/or remodel the chromatin structures. We isolated a novel nuclear protein based on its interaction with the recently described general coactivator activating signal cointegrator-2 (ASC-2). This protein CAPER (for coactivator of activating protein-1 (AP-1) and estrogen receptors (ERs)) selectively bound, among the many transcription factors we tested, the AP-1 component c-Jun and the estradiol-bound ligand binding domains of ERalpha and ERbeta. Interestingly, CAPER exhibited a cryptic autonomous transactivation function that becomes activated only in the presence of estradiol-bound ER. In cotransfections, CAPER stimulated transactivation by ERalpha, ERbeta, and AP-1. Thus, CAPER may represent a more selective transcriptional coactivator molecule that plays a pivotal role for the function of AP-1 and ERs in vivo in conjunction with the general coactivator ASC-2.
Jung
Dong-Ju
DJ
Department of Life Science, Pohang University of Science and Technology, Pohang 790-784, Korea.
Na
Soon-Young
SY
Na
Doe Sun
DS
Lee
Jae Woon
JW
D020816:Amino Acid Motifs; D000818:Animals; D002460:Cell Line; D003001:Cloning, Molecular; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D056918:Nuclear Receptor Coactivators; D011485:Protein Binding; D016755:Proto-Oncogene Proteins c-jun / Q000378:metabolism; D016601:RNA-Binding Proteins; D011960:Receptors, Estrogen / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D016415:Sequence Alignment; D015534:Trans-Activators / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D018808:Transcription Factor AP-1 / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism; D015533:Transcriptional Activation; D020798:Two-Hybrid System Techniques
D047908:Intracellular Signaling Peptides and Proteins; C486559:NCOA6 protein, human; D009687:Nuclear Proteins; D056918:Nuclear Receptor Coactivators; D016755:Proto-Oncogene Proteins c-jun; D016601:RNA-Binding Proteins; D011960:Receptors, Estrogen; D011993:Recombinant Fusion Proteins; C446024:Rnpc2 protein, mouse; D015534:Trans-Activators; D018808:Transcription Factor AP-1; D014157:Transcription Factors