| Summary: | <p>Abstract</p> <p>Background</p> <p>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 <it>TRIM5α </it>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 <it>Lepus</it>, <it>Sylvilagus </it>and <it>Oryctolagus</it>, we extended the study of evolutionary patterns of TRIM5α to other members of the Leporidae family, particularly to the genus <it>Sylvilagus</it>. Therefore, we obtained the <it>TRIM5α </it>nucleotide sequences of additional subspecies and species of the three leporid genera. We also compared lagomorph TRIM5α deduced protein sequences and established <it>TRIM5α </it>gene and TRIM5α protein phylogenies.</p> <p>Results</p> <p>The deduced protein sequence of Iberian hare TRIM5α was 89% identical to European rabbit TRIM5α, although high divergence was observed at the PRYSPRY v1 region between rabbit and the identified alleles from this hare species (allele 1: 50% divergence; allele 2: 53% divergence). A high identity was expected between the <it>Sylvilagus </it>and <it>Oryctolagus </it>TRIM5α proteins and, in fact, the <it>Sylvilagus </it>TRIM5α was 91% identical to the <it>Oryctolagus </it>protein. Nevertheless, the PRYSPRY v1 region was only 50% similar between these genera. Selection analysis of Lagomorpha TRIM5α proteins identified 25 positively-selected codons, 11 of which are located in the PRYSPRY v1 region, responsible for species specific differences in viral capsid recognition.</p> <p>Conclusions</p> <p>By extending Lagomorpha TRIM5α studies to an additional genus known to bear RELIK, we verified that the divergent species-specific pattern observed between the <it>Oryctolagus </it>and <it>Lepus </it>PRYSPRY-domains is also present in <it>Sylvilagus </it>TRIM5α. This work is one of the first known studies that compare the evolution of the antiretroviral restriction factor TRIM5α in different mammalian groups, Lagomorpha and Primates.</p>
|
|---|
