Study of Sylvilagus rabbit TRIM5α species-specific domain: how ancient endoviruses could have shaped the antiviral repertoire in Lagomorpha

Background Since the first report of the antiretroviral restriction factor TRIM5α in primates, several orthologs in other mammals have been described. Recent studies suggest that leporid retroviruses like RELIK, the first reported endogenous lentivirus ever, may have imposed positive selection in TRIM5α orthologs of the European rabbit and European brown hare. Considering that RELIK must already have been present in a common ancestor of the leporid genera Lepus, Sylvilagus and Oryctolagus, we extended the study of evolutionary patterns of TRIM5α to other members of the Leporidae family, particularly to the genus Sylvilagus. Therefore, we obtained the TRIM5α nucleotide sequences of additional subspecies and species of the three leporid genera. We also compared lagomorph TRIM5α deduced protein sequences and established TRIM5α gene and TRIM5α protein phylogenies.