COMPARISON OF THE ROTAVIRUS GENE-6 FROM DIFFERENT SPECIES BY SEQUENCE-ANALYSIS AND LOCALIZATION OF SUBGROUP-SPECIFIC EPITOPES USING SITE-DIRECTED MUTAGENESIS

The nucleotide sequence of gene 6 encoding the rotavirus major capsid protein VP6 of EDIM strain (EW) was determined and compared to that of 20 previously reported strains with known subgroup specificities. Mul tiple alignments of amino acid sequences exhibited a high level of seq uence conservation (87 to 99.2%). Site-specific mutagenesis experiment s were undertaken to localize regions involved in subgroup specificity . Aminoacid positions 305, 315, and a region 296-299 (or 301 for equin e strain H-2) were identified as contributing to subgroup epitopes. A single amino acid mutation at position 305 or 315 was sufficient to ch ange the subgroup specificity of EW VP6 protein from non I/II to subgr oup I- or subgroup II-like, respectively. Mutation at these sites may be another important mechanism for subgroup variation, along with gene reassortment. (C) 1997 Academic Press.