The TFIIB tip domain couples transcription initiation to events involved in RNA processing.
TFIIB is the only factor within the multimegadalton transcription complex that is obligatorily required to undergo dissociation and re-association with each round of mRNA transcription. Here we show that a six-amino acid human TFIIB tip region is needed for appropriate levels of serine 5 C-terminal domain phosphorylation and mRNA capping and for retention of the required elongation factor TFIIF. We suggest that the broad functions of this tiny region are used to suppress transcription noise by restricting functional RNA synthesis from non-promoter sites on the genome, which will not contain TFIIB.
Tran
Khiem
K
Department of Chemistry and Biochemistry and The Molecular Biology Institute, University of California, Los Angeles, California 90095, USA.
Gralla
Jay D
JD
D006367:HeLa Cells; D006801:Humans; D012315:RNA Caps / Q000235:genetics / Q000378:metabolism*; D012323:RNA Processing, Post-Transcriptional / Q000502:physiology*; D012331:RNA, Fungal / Q000096:biosynthesis / Q000235:genetics; D012568:Schizosaccharomyces / Q000235:genetics / Q000378:metabolism; D029702:Schizosaccharomyces pombe Proteins / Q000235:genetics / Q000378:metabolism; D035581:Transcription Factor TFIIB / Q000235:genetics / Q000378:metabolism*; D019473:Transcription Factors, TFII / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic / Q000502:physiology*; D015533:Transcriptional Activation / Q000502:physiology*
D012315:RNA Caps; D012331:RNA, Fungal; D029702:Schizosaccharomyces pombe Proteins; D035581:Transcription Factor TFIIB; D019473:Transcription Factors, TFII; C056604:transcription factor TFIIF