title: A cellular repressor regulates transcription initiation from the minute virus of mice P38 promoter.
abstract: We previously reported that the P38 promoter of minute virus of mice (MVM) is trans activated by the viral nonstructural protein, NS1, through an interaction with a downstream promoter element designated DPE. In this communication we report the identification of a distinct downstream promoter element which inhibits transcription from the P38 promoter in vitro, in the absence of the DPE. Removal of 34 bp from the region between +95 and +129 downstream from the P38 initiation start site relieved inhibition of transcription in whole-cell extract. Inhibition was also relieved by the addition, to the transcription reaction, of excess DNA fragments which span the putative inhibiting element. This indicated the involvement of a trans-acting factor, in inhibition of transcription from the P38. Gel retardation experiments demonstrated the specific binding of a cellular protein to the inhibitory element. This P38 inhibitory element shows spacing and orientation dependence as well as promoter specificity. The regulation of viral transcription by a cellular repressor may play an important role in obtaining a fine temporal order of viral gene expression during the course of infection.
authors.affiliation: Department of Molecular Genetics and Virology, Weizmann Institute of Science, Rehovot, Israel.
authors.forename: A
authors.initials: A
authors.lastname: Krauskopf
authors.forename: Y
authors.initials: Y
authors.lastname: Aloni
mesh_terms: D001483:Base Sequence; D004279:DNA, Viral; D015967:Gene Expression Regulation, Viral; D016325:HIV Long Terminal Repeat / Q000235:genetics; D006367:HeLa Cells; D006801:Humans; D008915:Minute Virus of Mice / Q000235:genetics*; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D012097:Repressor Proteins / Q000378:metabolism*; D014158:Transcription, Genetic
chemical_list: D004279:DNA, Viral; D012097:Repressor Proteins