Genetic recombination variation in wild Robertsonian mice: on the role of chromosomal fusions and Prdm9 allelic background.
Despite the existence of formal models to explain how chromosomal rearrangements can be fixed in a population in the presence of gene flow, few empirical data are available regarding the mechanisms by which genome shuffling contributes to speciation, especially in mammals. In order to shed light on this intriguing evolutionary process, here we present a detailed empirical study that shows how Robertsonian (Rb) fusions alter the chromosomal distribution of recombination events during the formation of the germline in a Rb system of the western house mouse (Mus musculus domesticus). Our results indicate that both the total number of meiotic crossovers and the chromosomal distribution of recombination events are reduced in mice with Rb fusions and that this can be related to alterations in epigenetic signatures for heterochromatinization. Furthermore, we detected novel house mouse Prdm9 allelic variants in the Rb system. Remarkably, mean recombination rates were positively correlated with a decrease in the number of ZnF domains in the Prdm9 gene. The suggestion that recombination can be modulated by both chromosomal reorganizations and genetic determinants that control the formation of double-stranded breaks during meiosis opens new avenues for understanding the role of recombination in chromosomal speciation.
Institut de Biotecnologia i Biomedicina (IBB), Universitat Autònoma de Barcelona, Campus UAB 08193, Barcelona, Spain Departament de Biologia Animal, Biologia Vegetal i Ecologia, Universitat Autònoma de Barcelona, Campus UAB 08193, Barcelona, Spain.
Laia
L
Capilla
Departament de Biologia Animal, Biologia Vegetal i Ecologia, Universitat Autònoma de Barcelona, Campus UAB 08193, Barcelona, Spain.
Nuria
N
Medarde
Unitat d'Investigació, Hospital Universitari Son Espases, Ctra Valldemossa 79, Palma 07010, Spain.
Alexandra
A
Alemany-Schmidt
Unitat d'Investigació, Hospital Universitari Son Espases, Ctra Valldemossa 79, Palma 07010, Spain.
Maria
M
Oliver-Bonet
Departament de Biologia Animal, Biologia Vegetal i Ecologia, Universitat Autònoma de Barcelona, Campus UAB 08193, Barcelona, Spain jacint.ventura.queija@uab.cat.
Jacint
J
Ventura
Institut de Biotecnologia i Biomedicina (IBB), Universitat Autònoma de Barcelona, Campus UAB 08193, Barcelona, Spain Departament de Biologia Cel·lular, Fisiologia i Immunologia, Universitat Autònoma de Barcelona, Campus UAB 08193, Barcelona, Spain aurora.ruizherrera@uab.cat.
Aurora
A
Ruiz-Herrera
D000483:Alleles; D000818:Animals; D000835:Animals, Wild / Q000235:genetics* / Q000378:metabolism; D002875:Chromosomes / Q000235:genetics* / Q000378:metabolism; D050939:Gene Fusion; D014644:Genetic Variation; D011495:Histone-Lysine N-Methyltransferase / Q000235:genetics* / Q000378:metabolism; D008297:Male; D051379:Mice / Q000235:genetics* / Q000378:metabolism; D011995:Recombination, Genetic / Q000235:genetics*; D013030:Spain
D011495:Histone-Lysine N-Methyltransferase; C534829:prdm9 protein, mouse
Prdm9; Robertsonian fusion; heterochromatinization; house mouse; recombination; speciation