Jaguar-specific duplication analysis unravels enrichment in the olfactory receptors gene family

PISCIOTTANO, FRANCISCO; LOSKA, DAMIAN; TARIFA, INTI; PENNA, CLEMENTINA; GABALDÓN, TONI; SARAGÜETA, PATRICIA

Ciudad Autónoma de Buenos Aires

Simposio; 3er Simposio Argentino de Jóvenes Investigadores en Bioinformática; 2018

Regional Student Group (RSG) associated to ISCB - Argentina

The olfactory receptor family (OR), which governs mammalian olfaction, is the largest and one of the most genetically diverse multigene families in vertebrates and its evolution has been suggested to be under the influence of balancing selection. The OR gene family has undergone extensive expansion and contraction through duplication and pseudogenization in the mammals and broadly defined environmental adaptations correlate with the number of functional and non-functional OR genes retained. Even though expansion of OR genes is regarded as a sustained evolutionary trend among cats (Felidae family), a significant expansion of the OR genes family has not been detected in the jaguar.Through a detailed analysis of the jaguar-specific duplications (JSDs) obtained by gene and species trees reconciliation from the jaguar phylome (i.e. the full collection of phylogenetic trees for all jaguar genes), and performing and orthology based filtering to exclude retrotransposon derived sequences from this data functional enrichment groups that had not been previously detected were revealed among JSDs. Although jaguar duplicated sequences had been previously filtered automatically to take out repetitive elements derived sequences, with our orthology based posterior filtering we removed as much as 14.3% of the remaining sequences, thus rendering only coding genes. A functional enrichment analysis performed over this new and clean jaguar-specific sequences duplication set revealed two overrepresented functional groups: ribosomal protein and olfactory receptors. Subsequent analysis of the 24 OR duplicated sequences in the jaguar showed a bias over odorants related to floral environment.Here we provide a detailed analysis of jaguar-specific gene duplications and show that the jaguar lineage has undergone specific expansion of the ORs gene family following the felid evolutionary tendency.