A new insight into RecA filament regulation by RecX from the analysis of conformation-specific interactions

  1. Aleksandr Alekseev  Is a corresponding author
  2. Georgii Pobegalov  Is a corresponding author
  3. Natalia Morozova
  4. Alexey Vedyaykin
  5. Galina Cherevatenko
  6. Alexander Yakimov
  7. Dmitry Baitin
  8. Mikhail Khodorkovskii
  1. Peter the Great St. Petersburg Polytechnic University, Russian Federation
  2. Kurchatov Institute, Russian Federation

Abstract

RecA protein mediates homologous recombination repair in bacteria through assembly of long helical filaments on single-stranded DNA (ssDNA) in an ATP dependent manner. RecX, an important negative regulator of RecA, is known to inhibit RecA activity by stimulating the disassembly of RecA nucleoprotein filaments. Here we use a single-molecule approach to address the regulation of (E. coli) RecA-ssDNA filaments by RecX (E. coli) within the framework of distinct conformational states of RecA-ssDNA filament. Our findings revealed that RecX effectively binds the inactive conformation of RecA-ssDNA filaments and slows down the transition to the active state. Results of this work provide new mechanistic insights into the RecX-RecA interactions and highlight the importance of conformational transitions of RecA filaments as an additional level of regulation of its biological activity.

Data availability

Source data files were provided for Figures 1, 2, 3, 4, 5 and Figures supplements.Raw fluorescent images of DNA tether were provided for Figure 4C as Zip file.

Article and author information

Author details

  1. Aleksandr Alekseev

    Peter the Great St. Petersburg Polytechnic University, St. Petersburg, Russian Federation
    For correspondence
    a.alekseev@nanobio.spbstu.ru
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4371-265X
  2. Georgii Pobegalov

    Peter the Great St. Petersburg Polytechnic University, St. Petersburg, Russian Federation
    For correspondence
    george.pobegalov@nanobio.spbstu.ru
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0836-0732
  3. Natalia Morozova

    Peter the Great St. Petersburg Polytechnic University, St. Petersburg, Russian Federation
    Competing interests
    The authors declare that no competing interests exist.
  4. Alexey Vedyaykin

    Peter the Great St. Petersburg Polytechnic University, St. Petersburg, Russian Federation
    Competing interests
    The authors declare that no competing interests exist.
  5. Galina Cherevatenko

    Peter the Great St. Petersburg Polytechnic University, St. Petersburg, Russian Federation
    Competing interests
    The authors declare that no competing interests exist.
  6. Alexander Yakimov

    Peter the Great St. Petersburg Polytechnic University, St. Petersburg, Russian Federation
    Competing interests
    The authors declare that no competing interests exist.
  7. Dmitry Baitin

    Kurchatov Institute, St. Petersburg, Russian Federation
    Competing interests
    The authors declare that no competing interests exist.
  8. Mikhail Khodorkovskii

    Peter the Great St. Petersburg Polytechnic University, St. Petersburg, Russian Federation
    Competing interests
    The authors declare that no competing interests exist.

Funding

Russian Science Foundation (19-74-10049)

  • Aleksandr Alekseev
  • Georgii Pobegalov
  • Alexander Yakimov

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

Reviewing Editor

  1. Maria Spies, University of Iowa, United States

Publication history

  1. Received: March 6, 2022
  2. Accepted: June 21, 2022
  3. Accepted Manuscript published: June 22, 2022 (version 1)

Copyright

© 2022, Alekseev 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. Aleksandr Alekseev
  2. Georgii Pobegalov
  3. Natalia Morozova
  4. Alexey Vedyaykin
  5. Galina Cherevatenko
  6. Alexander Yakimov
  7. Dmitry Baitin
  8. Mikhail Khodorkovskii
(2022)
A new insight into RecA filament regulation by RecX from the analysis of conformation-specific interactions
eLife 11:e78409.
https://doi.org/10.7554/eLife.78409
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