In vitro association between the Jun protein family and the general transcription factors, TBP and TFIIB.
Transcriptional activator proteins interact with the general transcription factors TATA-binding protein (TBP), TFIIB and/or other TBP-associated factors (TAFs). Using affinity chromatography we demonstrate that members of the Jun family of transcriptional activators interact with both TBP and TFIIB in vitro. TBP binds to both the N-terminal activation domain and C-terminal bZIP regions of c-Jun, whereas TFIIB binds to only the c-Jun bZIP domain. This interaction requires the dimerization of the Jun protein. The ability of the N-terminal activation domains of c-Jun, JunB, JunD and v-Jun to interact with TBP in vitro correlates with their transcriptional activity in vivo. Domain mapping experiments indicate that c-Jun interacts with the conserved C-terminus of TBP. Studies using a set of TFIIB inframe deletion mutants demonstrate that C-terminal amino acids 178-201 and 238-316 play an important role in modulating the interaction between TFIIB and c-Jun. Although phosphorylation of the c-Jun N-terminal activation domain stimulates c-Jun transcriptional activity in vivo, it has no effect on the ability of c-Jun to interact with either TBP or TFIIB in vitro. These data suggest that the Jun family of activator proteins may activate transcription by interacting with the general transcription factors TBP and TFIIB.
Division of Haematology and Oncology, University of Alabama at Birmingham 35294.
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Franklin
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McCulloch
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Kraft
D000818:Animals; D001665:Binding Sites; D002645:Chickens; D004247:DNA / Q000378:metabolism; D017353:Gene Deletion; D005982:Glutathione Transferase / Q000235:genetics; D006801:Humans; D016350:Leucine Zippers; D046911:Macromolecular Substances; D009994:Osmolar Concentration; D010446:Peptide Fragments / Q000737:chemistry; D010766:Phosphorylation; D016755:Proto-Oncogene Proteins c-jun / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011993:Recombinant Fusion Proteins; D013329:Structure-Activity Relationship; D035581:Transcription Factor TFIIB; D035362:Transcription Factor TFIID; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
D046911:Macromolecular Substances; D010446:Peptide Fragments; D016755:Proto-Oncogene Proteins c-jun; D011993:Recombinant Fusion Proteins; D035581:Transcription Factor TFIIB; D035362:Transcription Factor TFIID; D014157:Transcription Factors; D004247:DNA; D005982:Glutathione Transferase