Genetic basis of genome exclusion and clonal inheritance in hybridogenetic water frogs

• Applicants: Dr. Jörg Plötner; Dr. Montserrat Torres-Oliva; Professor Dr. Jochen B. W. Wolf
• Subject Area: Evolution, Anthropology ; General Genetics and Functional Genome Biology ; Bioinformatics and Theoretical Biology
• Term: since 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 433111196

European water frogs of the genus Pelophylax exhibit peculiarities allowing to study the mechanisms during male and female gametogenesis. In contrast to Mendelian species, certain interspecies hybrids reproduce hemiclonally by hybridogenesis: in their germ line they exclude the genome of one parental species and produce haploid gametes with an unrecombined genome of the other parental species. Although the genomic composition of hybrid germ cells has been previously described using conventional cytogenetic techniques, the molecular pathways that control the hybridogenetic events of genome exclusion remain unknown. We hypothesize that genomic and/or proteomic differences between parental genomes prevent chromosome pairing and thus promote the exclusion of one chromosome set in the hybrid germ line. Based on comparative transcriptome analysis in concert with artificial crossings we intend to identify the genes that regulate early meiotic events of recognition and pairing of homologous chromosomes using different Pelophylax species and their hybrids. From this approach we expect fundamental insights into early processes of meiosis that are relevant not only for anurans but for vertebrates in general.

• DFG Programme: Research Grants