1. Biochemistry and Chemical Biology
  2. Structural Biology and Molecular Biophysics
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Single-molecule studies contrast ordered DNA replication with stochastics translesion synthesis

  1. Gengjing Zhao
  2. Emma S Gleave
  3. Meindert Hugo Lamers  Is a corresponding author
  1. Medical Research Council, United Kingdom
Research Article
  • Cited 16
  • Views 2,335
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Cite this article as: eLife 2017;6:e32177 doi: 10.7554/eLife.32177


High fidelity replicative DNA polymerases are unable to synthesize past DNA adducts that result from diverse chemicals, reactive oxygen species or UV light. To bypass these replication blocks, cells utilize specialized translesion DNA polymerases that are intrinsically error prone and associated with mutagenesis, drug resistance, and cancer. How untimely access of translesion polymerases to DNA is prevented is poorly understood. Here we use co-localization single-molecule spectroscopy (CoSMoS) to follow the exchange of the E. coli replicative DNA polymerase Pol IIIcore with the translesion polymerases Pol II and Pol IV. We find that in contrast to the toolbelt model, the replicative and translesion polymerases do not form a stable complex on one clamp but alternate their binding. Furthermore, while the loading of clamp and Pol IIIcore is highly organized, the exchange with the translesion polymerases is stochastic and is not determined by lesion-recognition but instead a concentration-dependent competition between the polymerases.

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Author details

  1. Gengjing Zhao

    MRC Laboratory of Molecular Biology, Medical Research Council, Cambridge, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  2. Emma S Gleave

    MRC Laboratory of Molecular Biology, Medical Research Council, Cambridge, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  3. Meindert Hugo Lamers

    MRC Laboratory of Molecular Biology, Medical Research Council, Cambridge, United Kingdom
    For correspondence
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4205-1338


Medical Research Council (U105197143)

  • Gengjing Zhao
  • Emma S Gleave

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Taekjip Ha, Johns Hopkins University School of Medicine, United States

Publication history

  1. Received: September 21, 2017
  2. Accepted: December 5, 2017
  3. Accepted Manuscript published: December 6, 2017 (version 1)
  4. Accepted Manuscript updated: December 7, 2017 (version 2)
  5. Accepted Manuscript updated: December 11, 2017 (version 3)
  6. Version of Record published: December 15, 2017 (version 4)


© 2017, Zhao et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.


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