Characterization of the complete mitogenome of Indian Mouse Deer, Moschiola indica (Artiodactyla: Tragulidae) and its evolutionary significance.

The mitochondrial genome of Indian mouse deer (Moschiola indica) was sequenced, assembled and characterized for the first time using 22 pairs of polymerase chain reaction (PCR) primers. The mitogenome of M. indica which is 16,444 bp in size was found very similar to most vertebrates in organisation that harbours 13 protein-coding genes, 22 transfer RNA, 2 ribosomal RNA and 1A + T-rich region. Its comparison with over 52 mitogenomes of the order Artiodactyla, showed a conserved nature of gene organisation, codon usage, gene orientation and evolutionary rates of proteins except that M. indica possesses an extra copy of trnF. The complete mitogenome and protein-coding genes of M. indica were found to be highly A + T biased. Rate of protein evolution was highest in atp8 and lowest in cox3. Further, a higher purifying selection pressure was found to be acting on family Tragulidae compared to Bovidae and Cervidae. The phylogenetic analysis of M. indica placed the Tragulidae as sister-group of all other ruminants, similar to previous analyses. Moschiola forms the sister-group to the other two tragulid genera Tragulus (from Asia) and Hyemoschus (from Africa), which is unexpected as usually the Asian species are thought to form a monophyletic group.

Characterization of major histocompatibility complex class I, and class II DRB loci of captive and wild Indian leopards (Panthera pardus fusca).

The major histocompatibility complex (MHC), in vertebrate animals, is a multi-genic protein complex that encodes various receptors. During a disease, MHC interacts with the antigen and triggers a cascade of adaptive immune responses to overcome a disease outbreak. The MHC is very important region from immunological point of view, but it is poorly characterized among Indian leopards. During this investigation, we examined genetic diversity for MHC class I (MHC-I) and MHC class II-DRB (MHC-II) among wild and captive Indian leopards. This study estimated a pool of 9 and 17 alleles for MHC-I and MHC-II, respectively. The wild group of individuals showed higher nucleotide diversity and amino acid polymorphism compared to the captive group. A phylogenetic comparison with other felids revealed a clustering in MHC-I and interspersed presence in MHC-II sequences. A test for selection also revealed a deviation from neutrality at MHC-II DRB loci and higher non-synonymous substitution rate (dN) among the individuals from wild group. Further, the wild individuals showed higher dN for both MHC I and II genes compared to the group that was bred under captive conditions. These findings suggest the role of micro-evolutionary forces, such as pathogen-mediated selection, to cause MHC variations among the two groups of Indian leopards, because the two groups have been bred in two different environments for a substantial period of time. Since, MHC diversity is often linked with the quality of immunological health; the results obtained from this study fill the gap of knowledge on disease predisposition among wild and captive Indian leopards.