Modulation of Prdm9-controlled meiotic chromosome asynapsis overrides hybrid sterility in mice
- Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Czech Republic
Abstract
Hybrid sterility is one of the reproductive isolation mechanisms leading to speciation. Prdm9, the only known vertebrate hybrid sterility gene, causes failure of meiotic chromosome synapsis and infertility in male hybrids between two mouse subspecies. But within species Prdm9 determines the sites of programmed DNA double-strand breaks and meiotic recombination hotspots. To investigate the relation between Prdm9-controlled meiotic arrest and asynapsis, we inserted random stretches of consubspecific homology on several autosomal pairs in sterile hybrids and analyzed their ability to form synaptonemal complexes and rescue male fertility. Twenty-seven or more Mb of consubspecific (belonging to the same subspecies) homology fully restored synapsis in a given autosomal pair and we predicted that two or more DSBs within symmetric hotspots per chromosome are necessary for successful meiosis. We hypothesize that impaired recombination between evolutionarily diverged chromosomes could function as one of the mechanisms of hybrid sterility occurring in various sexually reproducing species.
Article and author information
Author details
Funding
Czech Science Fundation (13-08078S)
- Jiri Forejt
Charles University Grant Agency of The Czech Republic (435416)
- Vaclav Gergelits
- Barbora Valiskova
Ministry of Education, Youth and Sports of The Czech Republic (LQ1604 project of the NSPII)
- Jiri Forejt
Charles University Grant Agency of The Czech Republic (17115)
- Vaclav Gergelits
- Barbora Valiskova
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: The mice were maintained at the Institute of Molecular Genetics in Prague and Vestec, Czech Republic. The project was approved by the Animal Care and use Committee of the Institute of Molecular Genetics AS CR, protocol No 141/2012. The principles of laboratory animal care Czech Act No. 246/1992 Sb., compatible with EU Council Directive 86/609/EEC and Apendix of the Council of Europe Convention ETS, were observed.
Copyright
© 2018, Gregorova 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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Modulation of Prdm9-controlled meiotic chromosome asynapsis overrides hybrid sterility in mice
eLife 7:e34282.
https://doi.org/10.7554/eLife.34282
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