Structural highlights
Function
RPAB2_YEAST DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Common component of RNA polymerases I, II and III which synthesize ribosomal RNA precursors, mRNA precursors and many functional non-coding RNAs, and small RNAs, such as 5S rRNA and tRNAs, respectively. Pol II is the central component of the basal RNA polymerase II transcription machinery. Pols are composed of mobile elements that move relative to each other. In Pol II, RPB6 is part of the clamp element and togther with parts of RPB1 and RPB2 forms a pocket to which the RPB4-RPB7 subcomplex binds (By similarity).
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
We show that RNA polymerase (Pol) II prevents erroneous transcription in vitro with different strategies that depend on the type of DNARNA base mismatch. Certain mismatches are efficiently formed but impair RNA extension. Other mismatches allow for RNA extension but are inefficiently formed and efficiently proofread by RNA cleavage. X-ray analysis reveals that a TU mismatch impairs RNA extension by forming a wobble base pair at the Pol II active center that dissociates the catalytic metal ion and misaligns the RNA 3' end. The mismatch can also stabilize a paused state of Pol II with a frayed RNA 3' nucleotide. The frayed nucleotide binds in the Pol II pore either parallel or perpendicular to the DNA-RNA hybrid axis (fraying sites I and II, respectively) and overlaps the nucleoside triphosphate (NTP) site, explaining how it halts transcription during proofreading, before backtracking and RNA cleavage.
Structural basis of transcription: mismatch-specific fidelity mechanisms and paused RNA polymerase II with frayed RNA.,Sydow JF, Brueckner F, Cheung AC, Damsma GE, Dengl S, Lehmann E, Vassylyev D, Cramer P Mol Cell. 2009 Jun 26;34(6):710-21. PMID:19560423[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Sydow JF, Brueckner F, Cheung AC, Damsma GE, Dengl S, Lehmann E, Vassylyev D, Cramer P. Structural basis of transcription: mismatch-specific fidelity mechanisms and paused RNA polymerase II with frayed RNA. Mol Cell. 2009 Jun 26;34(6):710-21. PMID:19560423 doi:10.1016/j.molcel.2009.06.002
