Cooperatively between an upstream TATA-like sequence and a CAA repeated element mediates E1A-dependent negative repression of the H-2Kb class I gene.

X Tang; H O Li; O Sakatsume; T Ohta; H Tsutsui; A F Smit; M Horikoshi; P Kourilsky; A Israël; G Gachelin

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PubMed · 7836466

Cooperatively between an upstream TATA-like sequence and a CAA repeated element mediates E1A-dependent negative repression of the H-2Kb class I gene.

X Tang·H O Li·O Sakatsume·T Ohta·H Tsutsui·A F Smit·M Horikoshi·P Kourilsky·A Israël·G Gachelin

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Abstract

In primary rodent cells transformed by the E1A region of the highly oncogenic adenovirus type 12, repression of transcription mediated by the far upstream TATA-like element was observed only in conjunction with either possible juxtaposition of a CAA repeated element in the presence of E1A and was dependent upon the relative arrangement of both the TATA-like and CAA repeated motifs in both homologous and heterologous promoter constructs. A gel shift competition study demonstrated that the TATA-binding protein (TBP) or a TBP-like protein can bind to both the upstream TATA-like sequence and the regular TATA box on the H-2Kb basal promoter. Moreover, employing immunoselection and cyclic amplification and selection of targets (CASTing) methods with nuclear extracts derived from Ad12-E1A transformants, we have identified a high affinity binding site in the H-2Kb class I promoter for E1A-associated DNA-binding proteins. The sequences of the binding sites were identified and were found to contain both the upstream TATA-like motif and the CAA repeated motifs. Our results suggest that the TATA-like sequence in the far upstream region of the H-2Kb gene is one of the elements that is required for Ad12-E1A-mediated negative repression.

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Adenovirus E1A Proteins Animals Base Sequence Binding, Competitive Cell Transformation, Viral DNA-Binding Proteins Gene Expression Regulation H-2 Antigens Mice Molecular Sequence Data Promoter Regions, Genetic RNA, Messenger Regulatory Sequences, Nucleic Acid Repetitive Sequences, Nucleic Acid Repressor Proteins TATA Box Transcription, Genetic Journal Article Research Support, Non-U.S. Gov't

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X Tang, H O Li, O Sakatsume, T Ohta, H Tsutsui, A F Smit, M Horikoshi, P Kourilsky, A Israël, G Gachelin. 1995-02-03. Cooperatively between an upstream TATA-like sequence and a CAA repeated element mediates E1A-dependent negative repression of the H-2Kb class I gene.. https://pubmed.ncbi.nlm.nih.gov/7836466/

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