The molecular coupling between substrate recognition and ATP turnover in a AAA+ hexameric helicase loader

  1. Neha Puri
  2. Amy J Fernandez
  3. Valerie L O'Shea Murray
  4. Sarah McMillan
  5. James L Keck
  6. James M Berger  Is a corresponding author
  1. Johns Hopkins School of Medicine, United States
  2. University of Wisconsin School of Medicine and Public Health, United States
  3. Johns Hopkins University School of Medicine, United States

Abstract

In many bacteria and in eukaryotes, replication fork establishment requires the controlled loading of hexameric, ring-shaped helicases around DNA by AAA+ ATPases. How loading factors use ATP to control helicase deposition is poorly understood. Here, we dissect how specific ATPase elements of E. coli DnaC, an archetypal loader for the bacterial DnaB helicase, play distinct roles in helicase loading and the activation of DNA unwinding. We identify a new element, the arginine-coupler, which regulates the switch-like behavior of DnaC to prevent futile ATPase cycling and maintains loader responsiveness to replication restart systems. Our data help explain how the ATPase cycle of a AAA+-family helicase loader is channeled into productive action on its target; comparative studies indicate elements analogous to the Arg-coupler are present in related, switch-like AAA+ proteins that control replicative helicase loading in eukaryotes, as well as polymerase clamp loading and certain classes of DNA transposases.

Data availability

All data generated during this study is included in the manuscript and supplemental files.

Article and author information

Author details

  1. Neha Puri

    Department Biophysics and Biophysical Chemistry, Johns Hopkins School of Medicine, Baltimore, United States
    Competing interests
    Neha Puri, Neha Puri is affiliated with FogPharma. The author has no financial interests to declare..
  2. Amy J Fernandez

    Department of Biophysics and Biophysical Chemistry, Johns Hopkins School of Medicine, Baltimore, United States
    Competing interests
    No competing interests declared.
  3. Valerie L O'Shea Murray

    Department of Biophysics and Biophysical Chemistry, Johns Hopkins School of Medicine, Baltimore, United States
    Competing interests
    Valerie L O'Shea Murray, Valerie L. O'Shea Murray is affiliated with Saul Ewing Arnstein & Lehr, LLP. The author has no financial interests to declare..
  4. Sarah McMillan

    Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, United States
    Competing interests
    No competing interests declared.
  5. James L Keck

    Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, United States
    Competing interests
    No competing interests declared.
  6. James M Berger

    Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, United States
    For correspondence
    jberge29@jhmi.edu
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0666-1240

Funding

National Institute of General Medical Sciences (R37-GM71747)

  • James M Berger

National Institute of General Medical Sciences (R01-GM098885)

  • James L Keck

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

Reviewing Editor

  1. John Kuriyan, University of California, Berkeley, United States

Version history

  1. Received: October 21, 2020
  2. Accepted: May 25, 2021
  3. Accepted Manuscript published: May 26, 2021 (version 1)
  4. Version of Record published: June 18, 2021 (version 2)

Copyright

© 2021, Puri 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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  1. Neha Puri
  2. Amy J Fernandez
  3. Valerie L O'Shea Murray
  4. Sarah McMillan
  5. James L Keck
  6. James M Berger
(2021)
The molecular coupling between substrate recognition and ATP turnover in a AAA+ hexameric helicase loader
eLife 10:e64232.
https://doi.org/10.7554/eLife.64232

Share this article

https://doi.org/10.7554/eLife.64232

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