CHARACTERIZATION OF A ROTAVIRUS REARRANGED GENE-11 BY GENE REASSORTMENT

The effect of replacement of gene Ii of rotavirus SA-II by a gene carr ying a head to tail duplication obtained from a swine rotavirus strain was studied. The swine rotavirus strain with a duplicated gene (CC86) exhibits both a phenotype that allows to overgrow other viral strains when coinfected and an increased plaque size when plated in both CV-1 and MA-104 monkey kidney cells. Using reassortment methods the duplic ated gene of the swine rotavirus was introduced into the SA-11 virus, replacing the regular gene II. The reasserted strain was characterized to find out the origin of each of the other viral gene segments. Base d on electrophoretic mobilities segments 1, 2, 3, 5, 7, 8 and 10 were identified as of SA-11. The SA-11 origin of the segments 4, 6 and 9 wa s confirmed by neutralization with polyclonal and monoclonal antibodie s and by ELISA. The results suggest that the new reassortant virus was a monoreassortant carrying SA-11 genes except the duplicated gene ori ginated from the swine virus CC86. The ability to in vivo replicate an d to synthesize viral proteins was identical in the reasserted virus a nd the parental strains. Sequence analysis indicates that the new phen otype does not originate in the duplication of gene Il but possibly fr om mutations in the coding region of NSP5 gene that may result in diff erent phosphorylation patterns of the protein.