1r9s

From Proteopedia

RNA POLYMERASE II STRAND SEPARATED ELONGATION COMPLEX, MATCHED NUCLEOTIDE

Structural highlights

1r9s is a 10 chain structure with sequence from Saccharomyces cerevisiae. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	X-ray diffraction, Resolution 4.25Å
Ligands:	, ,
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

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

Binding of a ribonucleoside triphosphate to an RNA polymerase II transcribing complex, with base pairing to the template DNA, was revealed by X-ray crystallography. Binding of a mismatched nucleoside triphosphate was also detected, but in an adjacent site, inverted with respect to the correctly paired nucleotide. The results are consistent with a two-step mechanism of nucleotide selection, with initial binding to an entry (E) site beneath the active center in an inverted orientation, followed by rotation into the nucleotide addition (A) site for pairing with the template DNA. This mechanism is unrelated to that of single subunit RNA polymerases and so defines a new paradigm for the large, multisubunit enzymes. Additional findings from these studies include a third nucleotide binding site that may define the length of backtracked RNA; DNA double helix unwinding in advance of the polymerase active center; and extension of the diffraction limit of RNA polymerase II crystals to 2.3 A.

Structural basis of transcription: nucleotide selection by rotation in the RNA polymerase II active center.,Westover KD, Bushnell DA, Kornberg RD Cell. 2004 Nov 12;119(4):481-9. PMID:15537538^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Westover KD, Bushnell DA, Kornberg RD. Structural basis of transcription: nucleotide selection by rotation in the RNA polymerase II active center. Cell. 2004 Nov 12;119(4):481-9. PMID:15537538 doi:http://dx.doi.org/10.1016/j.cell.2004.10.016