Phosphoregulation of DSB-1 mediates control of meiotic double-strand break activity
Abstract
In the first meiotic cell division, proper segregation of chromosomes in most organisms depends on chiasmata, exchanges of continuity between homologous chromosomes that originate from the repair of programmed double-strand breaks (DSBs) catalyzed by the Spo11 endonuclease. Since DSBs can lead to irreparable damage in germ cells, while chromosomes lacking DSBs also lack chiasmata, the number of DSBs must be carefully regulated to be neither too high nor too low. Here, we show that in Caenorhabditis elegans, meiotic DSB levels are controlled by the phosphoregulation of DSB-1, a homolog of the yeast Spo11 cofactor Rec114, by the opposing activities of PP4PPH-4.1 phosphatase and ATRATL-1 kinase. Increased DSB-1 phosphorylation in pph-4.1 mutants correlates with reduction in DSB formation, while prevention of DSB-1 phosphorylation drastically increases the number of meiotic DSBs both in pph-4.1 mutants as well as in the wild type background. C. elegans and its close relatives also possess a diverged paralog of DSB-1, called DSB-2, and loss of dsb-2 is known to reduce DSB formation in oocytes with increasing age. We show that the proportion of the phosphorylated, and thus inactivated, form of DSB-1 increases with age and upon loss of DSB-2, while non-phosphorylatable DSB-1 rescues the age-dependent decrease in DSBs in dsb-2 mutants. These results suggest that DSB-2 evolved in part to compensate for the inactivation of DSB-1 through phosphorylation, to maintain levels of DSBs in older animals. Our work shows that PP4PPH-4.1, ATRATL-1, and DSB-2 act in concert with DSB-1 to promote optimal DSB levels throughout the reproductive lifespan.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files; numerical Source Data files have been provided for all plots and graphs
Article and author information
Author details
Funding
Japan Society for the Promotion of Science (5H04328)
- Peter M Carlton
Japan Society for the Promotion of Science (17K15064)
- Aya Sato-Carlton
Howard Hughes Medical Institute
- Abby F Dernburg
Naito Foundation
- Aya Sato-Carlton
Ministry of Education, Culture, Sports, Science and Technology
- Heyun Guo
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Federico Pelisch, University of Dundee, United Kingdom
Version history
- Preprint posted: February 17, 2022 (view preprint)
- Received: February 17, 2022
- Accepted: June 23, 2022
- Accepted Manuscript published: June 27, 2022 (version 1)
- Version of Record published: July 13, 2022 (version 2)
Copyright
© 2022, Guo 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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