Phylogenetic analysis of σB encoding gene of indigenous avian reovirus isolate

The σB protein of avian reovirus (ARV), one of the major structural proteins of outer capsid, is able to induce group specific neutralizing antibodies in chicks and thus provides protection against ARV strains of various serotypes. In this study, σB encoding gene of ARV field strain was amplified, cloned into pTZ57R/T vector, sequenced and finally subjected to phylogenetic analysis. The σB encoding gene of ARV is 1,104bp in size and has one open reading frame (ORF), which encodes 367 amino acids with a predicted molecular mass of approximately 41.5 kDa. The Indian ARV isolate was found to have at least 89.9% sequence homology with ARV isolates from other countries. However, it was found to share only 64.0% sequence homology with Muscovy duck reovirus strain 89026 and 70.6% and 71.2% identity with turkey reovirus strain NC98 and Tx99, respectively, which indicates that Indian ARV belongs to a different group. In the present study, the full length characterization and phylogenetic analysis of σB encoding gene by nucleotide sequencing was done and a genetic relationship between Indian isolate and other geographically different ARV isolates was observed. Nucleotide and deduced amino acid sequencing revealed that the Indian ARV isolate along with all other ARV isolates belong to same group.