Simian virus 40 (SV40) T-antigen transcriptional activation mediated through the Oct/SPH region of the SV40 late promoter.
Simian virus 40 (SV40) large T antigen is a promiscuous transcriptional activator of many viral and cellular promoters. The SV40 late promoter, a primary target for T-antigen transcriptional activation, contains a previously described T-antigen-activatable binding site (SV40 nucleotides 186 to 225). The T-antigen-activatable binding site element contains overlapping octamer (Oct)- and SPH (TEF-1)-binding sites (Oct/SPH site). Using this Oct/SPH site as an upstream element in a simple promoter, we show that the SPH sites are necessary for transcriptional activation by T antigen. In addition, we show that when Oct 1 is overproduced, it can eliminate T-antigen-mediated transcriptional activation, as well as basal activity, from the simple Oct/SPH promoter as well as the intact SV40 late promoter. This suggests that one function of T antigen in transcriptional activation of the late promoter is to alter factor binding at the Oct/SPH region to favor binding of factors to the SPH sites.
Gruda
M C
MC
Department of Microbiology, School of Medicine, University of Pennsylvania, Philadelphia 19104-6148.
Alwine
J C
JC
D000952:Antigens, Polyomavirus Transforming / Q000235:genetics*; D001483:Base Sequence; D004268:DNA-Binding Proteins / Q000502:physiology; D015967:Gene Expression Regulation, Viral; D051863:Host Cell Factor C1; D008969:Molecular Sequence Data; D050811:Octamer Transcription Factor-1; D011401:Promoter Regions, Genetic; D016755:Proto-Oncogene Proteins c-jun; D012045:Regulatory Sequences, Nucleic Acid; D013539:Simian virus 40 / Q000235:genetics*; D014157:Transcription Factors / Q000502:physiology; D014158:Transcription, Genetic; D015533:Transcriptional Activation
D000952:Antigens, Polyomavirus Transforming; D004268:DNA-Binding Proteins; D051863:Host Cell Factor C1; D050811:Octamer Transcription Factor-1; D016755:Proto-Oncogene Proteins c-jun; D014157:Transcription Factors