Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Science 29 May 2009:
Vol. 324. no. 5931, pp. 1203 - 1206
DOI: 10.1126/science.1168729
Prev | Table of Contents | Next

Reports

Structural Basis of Transcription: Backtracked RNA Polymerase II at 3.4 Angstrom Resolution

Dong Wang, David A. Bushnell, Xuhui Huang, Kenneth D. Westover, Michael Levitt, Roger D. Kornberg*

Transcribing RNA polymerases oscillate between three stable states, two of which, pre- and posttranslocated, were previously subjected to x-ray crystal structure determination. We report here the crystal structure of RNA polymerase II in the third state, the reverse translocated, or "backtracked" state. The defining feature of the backtracked structure is a binding site for the first backtracked nucleotide. This binding site is occupied in case of nucleotide misincorporation in the RNA or damage to the DNA, and is termed the "P" site because it supports proofreading. The predominant mechanism of proofreading is the excision of a dinucleotide in the presence of the elongation factor SII (TFIIS). Structure determination of a cocrystal with TFIIS reveals a rearrangement whereby cleavage of the RNA may take place.

Department of Structural Biology, Stanford University School of Medicine, Stanford, CA 94305, USA.

* To whom correspondence should be addressed. E-mail: kornberg{at}stanford.edu

Read the Full Text


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Allosteric control of catalysis by the F loop of RNA polymerase.
N. Miropolskaya, I. Artsimovitch, S. Klimasauskas, V. Nikiforov, and A. Kulbachinskiy (2009)
PNAS 106, 18942-18947
   Abstract »    Full Text »    PDF »


To Advertise     Find Products

Science. ISSN 0036-8075 (print), 1095-9203 (online)