Multi-genome comparisons reveal gain-and-loss evolution of anti-Mullerian hormone receptor type 2 as a candidate master sex-determining gene in Percidae
Heiner Kuhl,
Peter T. Euclide,
Christophe Klopp,
Cédric Cabau,
Margot Zahm,
Céline Lopez-Roques,
Carole Iampietro,
Claire Kuchly,
Cécile Donnadieu,
Romain Feron,
Hugues Parrinello,
Charles Poncet,
Lydia Jaffrelo,
Carole Confolent,
Ming Wen,
Amaury Herpin,
Elodie Jouanno,
Anastasia Bestin,
Pierrick Haffray,
Romain Morvezen,
Taina Rocha de Almeida,
Thomas Lecocq,
Bérénice Schaerlinger,
Dominique Chardard,
Daniel Żarski,
Wesley A. Larson,
John H. Postlethwait,
Serik Timirkhanov,
Werner Kloas,
Sven Wuertz,
Matthias Stöck,
Yann Guiguen
Affiliations
Heiner Kuhl
Leibniz-Institute of Freshwater Ecology and Inland Fisheries – IGB (Forschungsverbund Berlin)
Peter T. Euclide
Department of Forestry and Natural Resources | Illinois-Indiana Sea Grant, Purdue University
Abstract Background The Percidae family comprises many fish species of major importance for aquaculture and fisheries. Based on three new chromosome-scale assemblies in Perca fluviatilis, Perca schrenkii, and Sander vitreus along with additional percid fish reference genomes, we provide an evolutionary and comparative genomic analysis of their sex-determination systems. Results We explored the fate of a duplicated anti-Mullerian hormone receptor type-2 gene (amhr2bY), previously suggested to be the master sex-determining (MSD) gene in P. flavescens. Phylogenetically related and structurally similar amhr2 duplicates (amhr2b) were found in P. schrenkii and Sander lucioperca, potentially dating this duplication event to their last common ancestor around 19–27 Mya. In P. fluviatilis and S. vitreus, this amhr2b duplicate has been likely lost while it was subject to amplification in S. lucioperca. Analyses of the amhr2b locus in P. schrenkii suggest that this duplication could be also male-specific as it is in P. flavescens. In P. fluviatilis, a relatively small (100 kb) non-recombinant sex-determining region (SDR) was characterized on chromosome 18 using population-genomics approaches. This SDR is characterized by many male-specific single-nucleotide variations (SNVs) and no large duplication/insertion event, suggesting that P. fluviatilis has a male heterogametic sex-determination system (XX/XY), generated by allelic diversification. This SDR contains six annotated genes, including three (c18h1orf198, hsdl1, tbc1d32) with higher expression in the testis than in the ovary. Conclusions Together, our results provide a new example of the highly dynamic sex chromosome turnover in teleosts and provide new genomic resources for Percidae, including sex-genotyping tools for all three known Perca species.
