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A direct proofreader-clamp interaction stabilizes the Pol III replicase in the polymerization mode
Faculty of Science, Medicine and Health - Papers
  • Slobodan Jergic, University of Wollongong
  • Nicholas P Horan, University of Wollongong
  • Mohamed M Elshenawy, King Abdullah University of Science and Technology (KAUST)
  • Claire E Mason, University of Wollongong
  • Thitima Urathamakul, University of Wollongong
  • Kiyoshi Ozawa, University of Wollongong
  • Andrew Robinson, University of Wollongong
  • Joris MH Goudsmits, Harvard Medical School
  • Yao Wang, University of Wollongong
  • Xuefeng Pan, University of Wollongong
  • Jennifer L Beck, University of Wollongong
  • Antoine M van Oijen, Harvard Medical School
  • Thomas Huber, Australian National University
  • Samir M Hamdan, King Abdullah University of Science and Technology (KAUST)
  • Nicholas E Dixon, University of Wollongong
RIS ID
78677
Publication Date
1-1-2013
Publication Details

Jergic, S., Horan, N. P., Elshenawy, M. M., Mason, C. E., Urathamakul, T., Ozawa, K., Robinson, A., Goudsmits, J. MH., Wang, Y., Pan, X., Beck, J. L., van Oijen, A. M., Huber, T., Hamdan, S. M. & Dixon, N. E. (2013). A direct proofreader-clamp interaction stabilizes the Pol III replicase in the polymerization mode. The EMBO Journal, 32 (9), 1322-1333.

Abstract

Processive DNA synthesis by the αεθ core of the Escherichia coli Pol III replicase requires it to be bound to the β2 clamp via a site in the α polymerase subunit. How the ε proofreading exonuclease subunit influences DNA synthesis by α was not previously understood. In this work, bulk assays of DNA replication were used to uncover a non-proofreading activity of ε. Combination of mutagenesis with biophysical studies and single-molecule leading-strand replication assays traced this activity to a novel β-binding site in ε that, in conjunction with the site in α, maintains a closed state of the αεθ–β2 replicase in the polymerization mode of DNA synthesis. The ε–β interaction, selected during evolution to be weak and thus suited for transient disruption to enable access of alternate polymerases and other clamp binding proteins, therefore makes an important contribution to the network of protein–protein interactions that finely tune stability of the replicase on the DNA template in its various conformational states.

Grant Number
ARC/DP0877658
Grant Number
ARC/DP0984797
Citation Information
Slobodan Jergic, Nicholas P Horan, Mohamed M Elshenawy, Claire E Mason, et al.. "A direct proofreader-clamp interaction stabilizes the Pol III replicase in the polymerization mode" (2013)
Available at: http://works.bepress.com/nick_dixon/51/