title: Inhibition of p53 transactivation required for transformation by adenovirus early 1B protein.
abstract: The cellular phosphoprotein p53 inhibits progression through the mammalian cell cycle. Both p53 alleles are frequently mutated in human tumours, indicating that p53 is a tumour suppressor. Recent studies have suggested that p53 functions as a transcriptional activator, but the significance of this activity in cell-cycle control has not been established. The adenovirus 2 (Ad2) early 1B (E1B) 55K protein binds to p53 in transformed cells and contributes to oncogenic transformation by Ad2 (refs 10-12). Here we report that mutants of E1B 55K and wild-type Ad12 E1B 54K proteins show a strong correlation between their ability to inhibit p53-mediated transcriptional activation and their ability to cooperate with adenovirus E1A protein in the transformation of primary cells. These results indicate that p53 probably inhibits cell cycling by functioning as a transcription factor.
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: A J
authors.initials: AJ
authors.lastname: Berk
mesh_terms: D017456:Adenovirus Early Proteins; D000818:Animals; D002472:Cell Transformation, Viral / Q000502:physiology*; D002478:Cells, Cultured; D015870:Gene Expression; D009154:Mutation; D009856:Oncogene Proteins, Viral / Q000235:genetics / Q000502:physiology*; D011485:Protein Binding; D051381:Rats; D013329:Structure-Activity Relationship; D015533:Transcriptional Activation; D016159:Tumor Suppressor Protein p53 / Q000037:antagonists & inhibitors / Q000502:physiology*
chemical_list: D017456:Adenovirus Early Proteins; D009856:Oncogene Proteins, Viral; D016159:Tumor Suppressor Protein p53