Interaction of a common factor with ATF, Sp1, or TATAA promoter elements is required for these sequences to mediate transactivation by the adenoviral oncogene E1a.
The adenovirus protein E1a stimulates transcription of both viral and cellular genes. Unlike most other transcription factors, it induces transactivation through several different promoter elements. The mechanism by which elements of diverse sequence mediate the effect of E1a is the focus of this study. Three E1a-responsive elements (an ATF site, an Sp1 site, and a TATA box containing the sequence TATAA) were studied to determine whether their interaction with a common factor is necessary for transactivation. In transfection assays, each element was used as a competitor against promoter constructs containing the other elements. The elements as competitors had no effect on basal transcription, but each competitor completely inhibited transactivation by E1a. Competitors that were not E1a responsive failed to inhibit transactivation. Therefore, either E1a itself or an E1a-inducible factor interacts with each of the elements to cause transactivation, most likely though an association with each element's specific binding protein.
Weintraub
S J
SJ
Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110.
Dean
D C
DC
D051696:Activating Transcription Factors; D000256:Adenoviridae / Q000235:genetics*; D017456:Adenovirus Early Proteins; D000957:Antigens, Viral, Tumor / Q000235:genetics; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D001798:Blood Proteins / Q000235:genetics*; D002460:Cell Line; D004268:DNA-Binding Proteins / Q000235:genetics; D006801:Humans; D046911:Macromolecular Substances; D008969:Molecular Sequence Data; D009856:Oncogene Proteins, Viral / Q000235:genetics*; D010957:Plasmids / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000235:genetics*; D016329:Sp1 Transcription Factor / Q000235:genetics*; D016385:TATA Box / Q000235:genetics; D015534:Trans-Activators / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics*; D015533:Transcriptional Activation / Q000235:genetics*
D051696:Activating Transcription Factors; D017456:Adenovirus Early Proteins; D000957:Antigens, Viral, Tumor; D001798:Blood Proteins; D004268:DNA-Binding Proteins; D046911:Macromolecular Substances; D009856:Oncogene Proteins, Viral; D016329:Sp1 Transcription Factor; D015534:Trans-Activators; D014157:Transcription Factors