Hybrid Sterility Locus on Chromosome X Controls Meiotic Recombination Rate in Mouse

PLoS Genet. 2016 Apr 22;12(4):e1005906. doi: 10.1371/journal.pgen.1005906. eCollection 2016 Apr.

Abstract

Meiotic recombination safeguards proper segregation of homologous chromosomes into gametes, affects genetic variation within species, and contributes to meiotic chromosome recognition, pairing and synapsis. The Prdm9 gene has a dual role, it controls meiotic recombination by determining the genomic position of crossover hotspots and, in infertile hybrids of house mouse subspecies Mus m. musculus (Mmm) and Mus m. domesticus (Mmd), it further functions as the major hybrid sterility gene. In the latter role Prdm9 interacts with the hybrid sterility X 2 (Hstx2) genomic locus on Chromosome X (Chr X) by a still unknown mechanism. Here we investigated the meiotic recombination rate at the genome-wide level and its possible relation to hybrid sterility. Using immunofluorescence microscopy we quantified the foci of MLH1 DNA mismatch repair protein, the cytological counterparts of reciprocal crossovers, in a panel of inter-subspecific chromosome substitution strains. Two autosomes, Chr 7 and Chr 11, significantly modified the meiotic recombination rate, yet the strongest modifier, designated meiotic recombination 1, Meir1, emerged in the 4.7 Mb Hstx2 genomic locus on Chr X. The male-limited transgressive effect of Meir1 on recombination rate parallels the male-limited transgressive role of Hstx2 in hybrid male sterility. Thus, both genetic factors, the Prdm9 gene and the Hstx2/Meir1 genomic locus, indicate a link between meiotic recombination and hybrid sterility. A strong female-specific modifier of meiotic recombination rate with the effect opposite to Meir1 was localized on Chr X, distally to Meir1. Mapping Meir1 to a narrow candidate interval on Chr X is an important first step towards positional cloning of the respective gene(s) responsible for variation in the global recombination rate between closely related mouse subspecies.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • DNA Damage
  • Female
  • Genetic Linkage
  • Histone-Lysine N-Methyltransferase / genetics
  • Hybridization, Genetic*
  • Infertility, Male / genetics*
  • Male
  • Meiosis / genetics*
  • Mice
  • Recombination, Genetic*
  • X Chromosome*

Substances

  • Histone-Lysine N-Methyltransferase
  • prdm9 protein, mouse

Grant support

This work was funded by the Ministry of Education, Youth and Sports (http://www.msmt.cz/index.php?lang=2) project BIOCEV (CZ.1.05/1.1.00/02.0109) and by the Czech Science Foundation (http://gacr.cz/en/) grants 13-08078S to JF and 14-20728S to OM. CK short visit was supported by the Scholarship of the University of Veterinary Medicine, Vienna, Austria. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.