Assignment of simian rotavirus SA11 temperature-sensitive mutant groups A, C, F, and G to genome segments.

ABSTRACT

Crosses were performed between prototype temperature-sensitive (ts) mutants of simian rotavirus SA11 representing reassortment groups A, C, F, and G and ts mutants of rhesus rotavirus RRV that belonged to different reassortment groups. Wild-type (ts+) reassortant progeny were identified by plaque formation at nonpermissive temperature (39 degrees), picked, and grown to high titer. The ts+ phenotype of the resulting progeny clones was verified by titration at 39 degrees and 31 degrees. The electropherotypes of the ts+ clones were determined by electrophoresis, and parental origin of each genome segment was assigned by comparison of segment mobility to parental markers. Analysis of the parental origin of genome segments in the ts+ reassortants derived from SA11 ts X RRV ts crosses revealed the following map locations of the SA11 prototype ts mutants tsA(778), segment 4; tsC(606), segment 1; tsF(2124), segment 2; and tsG(2130), segment 6. The assignment of tsA was made on the basis of genome segment segregation in two independent crosses with each of two independent RRV ts mutants. The assignment of tsC was made on the basis of segregation in only a single cross with an RRV ts mutant; however, a larger number of progeny clones were examined from this cross. The lesion of tsF was mapped with data from three independent crosses using two different RRV ts mutants. The assignment of tsG was made on the basis of segregation in three independent crosses, two with RRV ts mutants and one with Wa. The assignments of tsA, tsC, and tsF were confirmed in crosses between RRV ts mutants representing those reassortment groups, and SA11 ts mutants in other reassortment groups.