A new insight into RecA filament regulation by RecX from the analysis of conformation-specific interactions
- Peter the Great St. Petersburg Polytechnic University, Russian Federation
- 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
Aleksandr Alekseev
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.
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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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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