Recurrent loss of crossover interference punctuates the recombination landscape across yeast species

Abstract

AbstractMeiotic recombination is essential for the accurate chromosome segregation and the generation of genetic diversity through crossover and gene conversion events. Although this process has been studied extensively in a few selected model species, understanding how its properties vary across species remains limited. In this context, we first characterized the meiotic recombination landscape and properties of theKluyveromyces lactisbudding yeast. We then conducted a comprehensive analysis of 28,897 recombination events spanning 567 meioses in five budding yeast species includingSaccharomyces cerevisiae,Saccharomyces paradoxus,Lachancea kluyveri,Lachancea waltiiandK. lactis. We observed variations in the recombination landscapes and properties across these species. TheSaccharomycesyeasts displayed higher recombination rates compared to the non-Saccharomycesyeasts. In addition, bona fide crossover interference and associated crossover homeostasis were found in theSaccharomycesspecies only. The evolutionarily conserved ZMM pathway, essential for generating interference-dependent crossovers, has undergone multiple losses throughout evolution, suggesting variations in the regulation of crossover formation. Finally, recombination hotspots, although highly conserved within theSaccharomycesyeasts are not conserved beyond theSaccharomycesgenus. Overall, these results highlight great variability and evolution in the recombination landscape between species.