Analysis of the VP6 gene of human and porcine group A rotavirus strains with unusual subgroup specificities

Abstract

Full-length VP6 amino acid sequences of human and porcine rotaviruses with subgroup (SG) (I þ II) and SG non-(I þ II) were analyzed in comparison with those of SG I and SG II. In human rotaviruses, the strains in the same SG shared a very high degree of amino acid identity, ranging from 97.4% to 99.4% for SG I, 95.9% to 100% for SG II, and 99.4% to100% for SG non-(I þ II), while viruses in different SGs shared somewhat lower sequence identity at 90.4-93.1%. Conserved amino acids that distinguished the strains of SG I from SG II were observed at 21 positions. The viruses with SG non-(I þ II) shared sequence identity with SG II as high as 97.2-99.7%, suggesting that they belonged to genogroup II. Similarly, porcine rotaviruses in the same SG shared 96.4-99.7% for SG I, 98.2-100% for SG II, 97.4-100% for SG (I þ II), and 96.2-99.7% for SG non-(I þ II), while strains in different SGs shared sequence identity ranging from 91.9% to 94.4%. Interestingly, the strains with SG (I þ II) and SG non-(I þ II) shared a high degree of sequence identity with SG I, at 96.4-100% and 94.7-99.7% respectively, suggesting that they are related to porcine SG I strains. The conserved amino acids which distinguished SG I from SG II were observed at 13 positions. The strains with SG I, SG (I þ II), and SG non-(I þ II) showed identical amino acid residues at these positions. Phylogenetic analysis strongly supported the findings of the sequence analysis.

Whole-genomic analysis of 12 porcine group A rotaviruses isolated from symptomatic piglets in Brazil during the years of 2012–2013

“…Specifically, the VP6-coding gene of the porcine viruses were divided into 2 sub-clades within the same I5 genotype and appeared genetically related to the VP6-coding gene of the human strain RVA/Human-tc/THA/ Mc323/1989/G9P[19], which was found to have a porcine RVA genetic backbone (Ghosh et al, 2012b). VP6 is one the most immunogenic proteins in RVA (Aiyebo et al, 2013), and it is well established that accumulation of point mutations in the VP6 gene may lead to a change of amino acid residues in the VP6 protein, resulting in antigenic variability (Thongprachum et al, 2009).…”

Zoonotic Potential of Rotavirus from Swine and Bovine in South of Taiwan

“…VP6 is one kind of major structural protein intermediate capsid layer of rotavirus virion, VP6 plays a role as a virulence factor of the virus pathogenesis. Characterization of VP6 gene is encoded 379 amino acid sequences [10].…”