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1r5u
From Proteopedia
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RNA POLYMERASE II TFIIB COMPLEX
Overview
The structure of the general transcription factor IIB (TFIIB) in a complex, with RNA polymerase II reveals three features crucial for transcription, initiation: an N-terminal zinc ribbon domain of TFIIB that contacts the, "dock" domain of the polymerase, near the path of RNA exit from a, transcribing enzyme; a "finger" domain of TFIIB that is inserted into the, polymerase active center; and a C-terminal domain, whose interaction with, both the polymerase and with a TATA box-binding protein (TBP)-promoter DNA, complex orients the DNA for unwinding and transcription. TFIIB stabilizes, an early initiation complex, containing an incomplete RNA-DNA hybrid, region. It may interact with the template strand, which sets the location, of the transcription start site, and may interfere with RNA exit, which, leads to abortive initiation or promoter escape. The trajectory of, promoter DNA determined by the C-terminal domain of TFIIB traverses sites, of interaction with TFIIE, TFIIF, and TFIIH, serving to define their roles, in the transcription initiation process.
About this Structure
1R5U is a Protein complex structure of sequences from Saccharomyces cerevisiae with ZN and MG as ligands. Active as DNA-directed RNA polymerase, with EC number 2.7.7.6 Full crystallographic information is available from OCA.
Reference
Structural basis of transcription: an RNA polymerase II-TFIIB cocrystal at 4.5 Angstroms., Bushnell DA, Westover KD, Davis RE, Kornberg RD, Science. 2004 Feb 13;303(5660):983-8. PMID:14963322
Page seeded by OCA on Wed Nov 21 01:17:14 2007
