title: Adenovirus E1B oncoprotein tethers a transcriptional repression domain to p53.
abstract: Many DNA tumor viruses express a protein that inhibits transcriptional activation by the tumor-suppressing transcription factor p53. We report that adenovirus E1B 55K represses p53-mediated activation by a mechanism not described previously. E1B 55K binds p53 without displacing it from its DNA-binding site. A fusion of E1B 55K to the GAL4 DNA-binding domain represses transcription from a variety of promoters with engineered upstream GAL4-binding sites. Mutations within E1B 55K that interfere with its transforming activity and its ability to inhibit p53-mediated trans-activation also interfere with transcriptional repression by the GAL4-55K fusion. These results demonstrate that E1B 55K functions as a direct transcriptional repressor that is targeted to p53-responsive genes by binding to p53.
authors.affiliation: Department of Microbiology and Molecular Genetics, University of California, Los Angeles 90024-1570.
authors.forename: P R
authors.initials: PR
authors.lastname: Yew
authors.forename: X
authors.initials: X
authors.lastname: Liu
authors.forename: A J
authors.initials: AJ
authors.lastname: Berk
mesh_terms: D017501:Adenovirus E1B Proteins / Q000378:metabolism*; D000595:Amino Acid Sequence; D001483:Base Sequence; D002478:Cells, Cultured; D004268:DNA-Binding Proteins; D005656:Fungal Proteins / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides; D009856:Oncogene Proteins, Viral / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D012097:Repressor Proteins / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D014158:Transcription, Genetic; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism*
chemical_list: D017501:Adenovirus E1B Proteins; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; C052130:GAL4 protein, S cerevisiae; D009838:Oligodeoxyribonucleotides; D009856:Oncogene Proteins, Viral; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D016159:Tumor Suppressor Protein p53