[Sequence analysis of the serotype specific gene fragment of VP4 from three rotavirus field strains]

Rotaviruses are the major pathogens that cause life threatening diarrhea in young children and animals. The 4th gene, encodes the nonglycosylated major neutralizing protein VP4 which can be cleaved into VP8 and VP5. The regions of the fourth genes coding for the VP8 protein, downstream cleavage site and the NH2 terminus of VP5 from three Beijing human rotavirus field strains (T65 [P1A], R50[P1B], N16[P2]) were cloned and sequenced. Comparative analysis of the deduced amino acid sequences of these 887 bp fragments from three strains indicates a high degree of homology (92%-96.6%) between field and reference strains within the same serotype and a high degree of divergence (70.5%-71%) among different serotypes. Notably, the most divergence of amino acid sequence is located in a region delimited by aa 84-172 of VP8 protein. In addition, the possibility of trypsin cleavage sites in virulence is discussed.