Origin of PRDM9-dependent meiotic hotspots: where, how and why recombine? – HotRec

In many eukaryotic genomes, meiotic recombination is concentrated in hotspots. In fungi, plants and birds, hotspots are located in promoters and long-lived. In contrast, in humans and mice, recombination is targeted away from genes by PRDM9 and, through an intra-genomic conflict, hotspots are self-destructive and short-lived. The reasons for these intriguing patterns and their impact on selection efficacy and genome evolution are totally unknown. PRDM9 was present in the ancestor of metazoans but has been lost in several lineages. However, so far, the activity of PRDM9 has been analyzed only in two mammals. To elucidate the origin of PRDM9-dependent hotspots, we will generate fine-scale recombination maps and collect population genomic datasets in 4 non-mammalian metazoans. We will combine cutting-edge molecular, theoretical and computational tools to analyze the dynamics of recombination landscapes, quantify their impacts on genomes and thus uncover the ‘raison d’être’ of hotspots.