A TBP complex essential for transcription from TATA-less but not TATA-containing RNA polymerase III promoters is part of the TFIIIB fraction

Cell. 1992 Dec 11;71(6):1029-40. doi: 10.1016/0092-8674(92)90397-u.

Abstract

The TATA box-binding protein TBP directs transcription by all three eukaryotic RNA polymerases. In mammalian cells, TBP is found in at least three different complexes: SL1, D-TFIID, and B-TFIID. While SL1 and D-TFIID are involved in RNA polymerase I and II transcription, respectively, no unique function has been assigned to the B-TFIID complex. Here we show that the TFIIIB fraction required for RNA polymerase III transcription contains two separable components, one of which is a TBP-containing complex that may correspond to B-TFIID. For transcription of TATA-less RNA polymerase III genes such as the VAI, 5S, and 7SL genes, this complex cannot be replaced by either TBP alone or the D-TFIID complex. In contrast, TBP alone is active for basal transcription from the TATA-containing U6 promoter. This indicates different requirements for recruiting TBP to TATA-less and TATA-containing RNA polymerase III promoters.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Base Sequence
  • DNA Polymerase III
  • DNA-Binding Proteins / chemistry*
  • DNA-Directed RNA Polymerases / genetics
  • Molecular Sequence Data
  • Multienzyme Complexes / chemistry
  • Promoter Regions, Genetic
  • TATA-Box Binding Protein
  • Transcription Factor TFIIIB
  • Transcription Factors / chemistry*
  • Transcription, Genetic*

Substances

  • DNA-Binding Proteins
  • Multienzyme Complexes
  • TATA-Box Binding Protein
  • Transcription Factor TFIIIB
  • Transcription Factors
  • DNA-Directed RNA Polymerases
  • DNA Polymerase III