Transcriptional repressor of vasoactive intestinal peptide receptor mediates repression through interactions with TFIIB and TFIIEbeta.
The transcriptional repressor for rat vasoactive-intestinal-polypeptide receptor 1 (VIPR-RP) is a recently characterized transcription factor that belongs to a family of proteins, which include components of the DNA replication factor C complex. In this study, I investigated the mechanisms by which VIPR-RP represses transcription. I show here that transcriptional repression by VIPR-RP is mediated by a histone deacetylase-independent mechanism. I provide evidence that VIPR-RP makes direct physical contacts with two proteins of the basal transcription apparatus, the transcription factors TFIIB and TFIIEbeta. The interaction with TFIIB is mediated by the N-terminal 180 amino acids, whereas the interactive domain with TFIIEbeta is located between residues 367 and 527 of VIPR-RP. Using gel mobility-shift assays I demonstrated that interaction between VIPR-RP and TFIIB prevents the recruitment of TFIIB into a DNA-TATA-box-binding protein complex. My results indicate that VIPR-RP mediates transcriptional repression through direct interactions with the general transcription machinery.
Pei
L
L
Division of Endocrinology & Metabolism, Cedars-Sinai Research Institute-UCLA School of Medicine, 8700 Beverly Boulevard, Los Angeles, CA 90048, U.S.A. lpei@tularik.com
D000818:Animals; D019556:COS Cells; D002460:Cell Line; D002522:Chlorocebus aethiops; D017930:Genes, Reporter; D005982:Glutathione Transferase / Q000235:genetics; D008156:Luciferases / Q000235:genetics; D014176:Protein Biosynthesis; D051818:Replication Protein C; D012097:Repressor Proteins / Q000378:metabolism*; D035581:Transcription Factor TFIIB; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D019473:Transcription Factors, TFII; D014158:Transcription, Genetic; D014162:Transfection
D012097:Repressor Proteins; C113967:Rfc1 protein, rat; D035581:Transcription Factor TFIIB; D014157:Transcription Factors; D019473:Transcription Factors, TFII; C066644:transcription factor TFIIE; D008156:Luciferases; D005982:Glutathione Transferase; D051818:Replication Protein C