author(s)
Karthikeyan A, Radhika G and Aravindakshan TV

abstract
Characterization of the genes pertaining to immune system in Vechur cattle might provide an insight into the mechanisms involved in disease resistance in general and may aid in breeding animals for disease resistance. Osteopontin (OPN), a phosphoprotein plays various roles in immune response, such as activating macrophages, acting as chemokine, attracting neutrophils, delaying cell apoptosis, opsonizing bacteria, acting as pro-inflammatory, aiding in angiogenesis and tissue remodelling. The present study was framed to characterize the OPN genes in Vechur cattle. Characterization revealed 909 bp length OPN mRNA contained protein coding open reading frame of 834 bp which codes for 278 amino acids. Pair blasting with Bos taurus sequence (NM_174187.2) displayed 99 per cent homology and other related ruminant species in close proximity. Sequence analysis for presence of any nucleotide variation disclosed three novel nucleotide transitions in coding region and two non-synonymous transitions at 188th and 229th position of nucleotide sequence. Serine amino acid was found to be highest frequency of 15.11 per cent of total protein constituting the primary OPN protein. In-silico analysis of predicted OPN protein sequence showed presence of signal peptide and nature of protein suggesting secretory type protein. The observed variation in nucleotide sequence of mRNA sequences and it predicted protein of OPN gene in Vechur cattle may pave way for further study on association between existing polymorphisms and host disease resistance nature in those breeds.