Exploring the genetic basis and evolution of Pantherine historical inter-specific hybridization

CAMPOS, CLARA; PENNA, CLEMENTINA; BRUQUE, CARLOS DAVID; PISCIOTTANO, FRANCISCO; SARAGÜETA, PATRICIA

Congreso; XI Congreso Argentino de Bioinformática y Biología Computacional; 2021

Asociación Argentina de Bioinformática y Biología Computacional

Exploring the genetic basis and evolution of Pantherine historicalinter-specific hybridizationClara Campos, Clementina Penna, David Bruque, Francisco Pisciottanoand Patricia Saragüeta1Instituto de Biología y Medicina Experimental - CABA, Provincia de Buenos Aires, Argentina 2 Unidad de ConocimientoTraslacional Hospitalaria Patagónica, Hospital de Alta Complejidad SAMIC - El Calafate, Provincia de Santa Cruz, ArgentinaBackground:Genomic introgression analysis exposed a complex pattern of historical inter-specific hybridizationin the Pantherinae lineage. This findings revealed unusually high rates of fertilization amongpantherines, particularly between Panthera leo and Panthera onca, that would indicate an absenceof inter-specific isolation barriers.Zona Pellucida (ZP) and Juno (IZUMO1R) oocyte proteins play a key role in mammalian fertilizationprocess, facilitating the interaction and fusion between the oocyte and the sperm respectively.Specifically ZP2 and ZP3 are directly involved in the interaction between gametes, ZP1 and ZP4 playthe role of crosslinkers. Their interaction with sperm counterparts is essential for gameteinteraction and the lack of recognition between them can constitute a pre-cigotic reproductiveisolation mechanism. Hi-C long-range sequencing and chromosome-resolved genome assembly wasused to reconstruct the intricate phylogeny of gamete interaction proteins to uncover theunderlying molecular basis of inter-species crossing and evolution of the functional capacities ofpantherinesResults:In this work we explored the evolutionary patterns of ZP1, ZP2, ZP3, ZP4 and Juno proteins in thepantherines as well as in Feliformia and Caniformia suborders and the whole Carnivora orderdetecting adaptive changes, pairwise sequence identity and similarity analysis and evolutionaryrelevant sites based on curated multiple sequence alignments.The conservation of all carnivora gamete interaction proteins was significantly higher (p-value <0.05) in feliformes compared to caniformes except for the case of ZP4. ZP3 and ZP2 proteinsdisplayed a similar pattern of evolution along their phylogenies showing adaptive changes incaniformes subtree but not among felid species. On the other hand, both ZP1 and ZP4 display adifferent evolutionary history, showing signatures of positive selection inside felids subtree. Thefusion protein IZUMO1R did not show positive selection among all studied phylogenetic groupsConclusions:These results strengthen the idea that ZPs are proteins that provide a more specific-specificityisolation than IZUMO1R, which is specialized in fusion events. Altogether, our findings indicate thatsperm-oocyte interaction and fusion proteins lack the degree of diversification necessary to fix aprezygotic reproductive isolation barrier in felidae.Submission track: Evolutionary, compressive and comparative genomics.