Structural Basis of Transcription: An RNA Polymerase II Elongation Complex at 3.3 Å Resolution
10.1126/science.1059495
Crossref journal-article
American Association for the Advancement of Science (AAAS)
Science (221)
Abstract

The crystal structure of RNA polymerase II in the act of transcription was determined at 3.3 Å resolution. Duplex DNA is seen entering the main cleft of the enzyme and unwinding before the active site. Nine base pairs of DNA-RNA hybrid extend from the active center at nearly right angles to the entering DNA, with the 3′ end of the RNA in the nucleotide addition site. The 3′ end is positioned above a pore, through which nucleotides may enter and through which RNA may be extruded during back-tracking. The 5′-most residue of the RNA is close to the point of entry to an exit groove. Changes in protein structure between the transcribing complex and free enzyme include closure of a clamp over the DNA and RNA and ordering of a series of “switches” at the base of the clamp to create a binding site complementary to the DNA-RNA hybrid. Protein–nucleic acid contacts help explain DNA and RNA strand separation, the specificity of RNA synthesis, “abortive cycling” during transcription initiation, and RNA and DNA translocation during transcription elongation.

Bibliography

Gnatt, A. L., Cramer, P., Fu, J., Bushnell, D. A., & Kornberg, R. D. (2001). Structural Basis of Transcription: An RNA Polymerase II Elongation Complex at 3.3 Å Resolution. Science, 292(5523), 1876–1882.

Authors 5
  1. Averell L. Gnatt (first)
  2. Patrick Cramer (additional)
  3. Jianhua Fu (additional)
  4. David A. Bushnell (additional)
  5. Roger D. Kornberg (additional)
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  60. For assistance at beamlines 1-5 7-1 9-1 and 9-2 of the Stanford Synchrotron Radiation Laboratory (SSRL) we thank H. Bellamy A. Cohen P. Ellis P. Kuhn T. McPhillips M. Soltis and the other members of the SSRL user support staff. This research is based in part on work done at SSRL which is funded by the U.S. Department of Energy (DOE) Office of Basic Energy Sciences. The structural biology program is supported by the NIH National Center for Research Resources Biomedical Technology Program and the DOE Office of Biological and Environmental Research. We thank COMPAQ for providing a Unix workstation. We thank N. Thompson and R. Burgess for generously providing antibody for protein purification. We thank J. Puglisi and members of the Kornberg laboratory for comments on the manuscript. The contribution of A.L.G. was sponsored by USAMRMC Breast Cancer Initiative DAMD17-97-7099 and does not necessarily reflect the policy of the government. P.C. was supported by a postdoctoral fellowship of the Deutsche Forschungsgemeinschaft (DFG). D.A.B. was supported by postdoctoral fellowship PF-00-014-01-GMC from the American Cancer Society. This research was supported by NIH grant GM49985 to R.D.K. Coordinates have been deposited at the Protein Data Bank (accession code 1I6H).
Dates
Type When
Created 23 years ago (July 27, 2002, 5:52 a.m.)
Deposited 1 year, 7 months ago (Jan. 9, 2024, 5:26 p.m.)
Indexed 0 minutes ago (Aug. 26, 2025, 11:47 p.m.)
Issued 24 years, 2 months ago (June 8, 2001)
Published 24 years, 2 months ago (June 8, 2001)
Published Print 24 years, 2 months ago (June 8, 2001)
Funders 0

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@article{Gnatt_2001, title={Structural Basis of Transcription: An RNA Polymerase II Elongation Complex at 3.3 Å Resolution}, volume={292}, ISSN={1095-9203}, url={http://dx.doi.org/10.1126/science.1059495}, DOI={10.1126/science.1059495}, number={5523}, journal={Science}, publisher={American Association for the Advancement of Science (AAAS)}, author={Gnatt, Averell L. and Cramer, Patrick and Fu, Jianhua and Bushnell, David A. and Kornberg, Roger D.}, year={2001}, month=jun, pages={1876–1882} }