DNA polymerase V activity is autoregulated by a novel intrinsic DNA-dependent ATPase

  1. Aysen L Erdem
  2. Malgorzata Jaszczur
  3. Jeffrey G Bertram
  4. Roger Woodgate
  5. Michael M Cox
  6. Myron F Goodman  Is a corresponding author
  1. University of Southern California, United States
  2. National Institute of Child Health and Human Development, National Institutes of Health, United States
  3. University of Wisconsin-Madison, United States

Abstract

Escherichia coli DNA polymerase V (pol V), a heterotrimeric complex composed of UmuD′2C, is marginally active. ATP and RecA play essential roles in the activation of pol V for DNA synthesis including translesion synthesis (TLS). We have established three features of the roles of ATP and RecA. 1) RecA-activated DNA polymerase V (pol V Mut), is a DNA-dependent ATPase; 2) bound ATP is required for DNA synthesis; 3) pol V Mut function is regulated by ATP, with ATP required to bind primer/template (p/t) DNA and ATP hydrolysis triggering dissociation from the DNA. Pol V Mut formed with an ATPase-deficient RecA E38K/K72R mutant hydrolyzes ATP rapidly, establishing the DNA-dependent ATPase as an intrinsic property of pol V Mut distinct from the ATP hydrolytic activity of RecA when bound to single-stranded (ss)DNA as a nucleoprotein filament (RecA*). No similar ATPase activity or autoregulatory mechanism has previously been found for a DNA polymerase.

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Author details

  1. Aysen L Erdem

    University of Southern California, Los Angeles, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Malgorzata Jaszczur

    University of Southern California, Los Angeles, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Jeffrey G Bertram

    University of Southern California, Los Angeles, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Roger Woodgate

    National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Michael M Cox

    University of Wisconsin-Madison, Madison, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Myron F Goodman

    University of Southern California, Los Angeles, United States
    For correspondence
    mgoodman@usc.edu
    Competing interests
    The authors declare that no competing interests exist.

Copyright

© 2014, Erdem et al.

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

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  1. Aysen L Erdem
  2. Malgorzata Jaszczur
  3. Jeffrey G Bertram
  4. Roger Woodgate
  5. Michael M Cox
  6. Myron F Goodman
(2014)
DNA polymerase V activity is autoregulated by a novel intrinsic DNA-dependent ATPase
eLife 3:e02384.
https://doi.org/10.7554/eLife.02384

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https://doi.org/10.7554/eLife.02384

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