Interaction of the Dr1 inhibitory factor with the TATA binding protein is disrupted by adenovirus E1A

Howard Hughes Medical Institute, Department of Genetics, Duke University Medical Center, Durham, NC 27710.
Proceedings of the National Academy of Sciences (Impact Factor: 9.67). 08/1994; 91(14):6279-82. DOI: 10.1073/pnas.91.14.6279
Source: PubMed


Past experiments have shown that the adenovirus E1A12S product activates the hsp70 promoter, dependent on the TATA element and dependent on N-terminal E1A sequences. Other experiments have identified a factor termed Dr1 that interacts with and inhibits the transcriptional activity of the TATA-binding protein (TBP). We now find that the E1A12S protein can disrupt the interaction of the Dr1 factor with the TATA-specific TBP factor, allowing the productive interaction of TBP with TFIIA. This E1A-mediated disruption is dependent on N-terminal sequences that are also essential for the TATA-dependent trans-activation of the hsp70 promoter. Moreover, we also find that Dr1 expression in transfected cells can inhibit transcription from the hsp70 promoter and that this can be overcome by coexpression of the wild-type E1A protein, dependent on N-terminal sequences. We conclude that the activation of hsp70 through the TATA element may be mechanistically similar to the activation of the E2 promoter via E2F, in each case involving a release of a transcription factor from an inactive complex.

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Available from: Kam C Yeung, Jan 03, 2014
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    • "However, other gene promoters may be activated by sequences found within E1A 1–80. For example hsp70 has been reported to be activated by sequences within the E1A repression domain by a mechanism which involves the disruption of binding of the Dr1 transcriptional repressor to the TATA sequence by E1A (Kraus et al., 1994). However, it seems unlikely that this mechanism is responsible for the activation seen in this temporal assay. "
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    ABSTRACT: The adenovirus repression domain of E1A 243R at the E1A N-terminus (E1A 1-80) transcriptionally represses genes involved in differentiation and cell cycle progression. E1A 1-80 represses transcription in vitro from naked DNA templates through its interaction with p300 and TFIID. E1A 1-80 can also interact with several chromatin remodeling factors and associates with chromatin in vivo. We show here that E1A 243R and E1A 1-80 can repress transcription from a reconstituted chromatin template in vitro. Temporal analysis reveals strong repression by E1A 1-80 when added at pre-activation, activation and early transcription stages. Interestingly, E1A 1-80 can greatly enhance transcription from chromatin templates, but not from naked DNA, when added at pre-initiation complex (PIC) formation and transcription-initiation stages. These data reveal a new dimension for E1A 1-80's interface with chromatin and may reflect its interaction with key players in PIC formation, p300 and TFIID, and/or possibly a role in chromatin remodeling.
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    • "Adenoviridae AdV , E1A , E1B Hsp70 Induction of hsp70 / hdj1 transcrip - tion , mRNA export Agoff and Wu 1994 ; Glotzer et al . 2000 ; Herrmann et al . 1987 ; Kao et al . 1985 ; Kao and Nevins 1983 ; Kraus et al . 1994 ; Lum et al . 1992 ; Milarski and Morimoto 1986 ; Moore et al . 1987 ; Nevins 1982 ; Phillips and Morimoto 1991 ; Simon et al . 1987 ; Theodorakis and Morimoto 1987 ; Williams et al . 1989 ; Wu et al . 1986 ; Yang et al . 1996 AdV hexon Hsp70 , Hsc70"
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    • "E1A ∆26–35 is defective in interacting with p400, a cellular E1A-binding protein which remains to be cloned and characterized (Howe and Bayley, 1992; Barbeau et al., 1994). In addition, a region spanning residues 2–36 of E1A is involved in interaction with the transcriptional regulators Dr1, YY-1 and AP-2, as well as with several uncharacterized cellular proteins (Kraus et al., 1994; White et al., 1994; Lee et al., 1995a, 1995b; Lewis et al., 1995; Somasundaram et al., 1996; Sang and Giordano, 1997). It remains to be investigated whether any of these interactions is related to the biological activity of E1A uncovered in this work. "
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