Article

Binding of TFIIB to RNA polymerase II: Mapping the binding site for the TFIIB zinc ribbon domain within the preinitiation complex.

Fred Hutchinson Cancer Research Center and Howard Hughes Medical Institute, 1100 Fairview Avenue N., Mail Stop A1-162, Seattle, WA 98109, USA.
Molecular Cell (impact factor: 14.18). 09/2003; 12(2):437-47. pp.437-47
Source: PubMed

ABSTRACT RNA polymerase II (Pol II) is recruited to promoters by interaction with general transcription factors. The zinc ribbon domain of the general factor TFIIB is essential for Pol II recruitment. Site-specific photocrosslinking and directed hydroxyl radical probing were used to map the location of the TFIIB zinc ribbon domain on Pol II within the transcription preinitiation complex (PIC). These results, along with mutational analysis, suggest that in the PIC, the TFIIB ribbon domain interacts with a surface of the Pol II Dock domain where it overlaps the RNA exit point. This surface is best conserved in polymerases that require a TFIIB-like factor. Our results suggest a general mechanism for interaction of TFIIB-like factors and RNA polymerases and a mechanism for the function of the ribbon domain.

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Keywords

general factor TFIIB
 
general mechanism
 
general transcription factors
 
PIC
 
Pol II
 
Pol II Dock domain
 
Pol II recruitment
 
polymerases
 
ribbon domain
 
RNA exit point
 
RNA polymerase II
 
RNA polymerases
 
Site-specific photocrosslinking
 
TFIIB ribbon domain interacts
 
TFIIB zinc ribbon domain
 
TFIIB-like factor
 
TFIIB-like factors
 
transcription preinitiation complex
 
zinc ribbon domain