ISOLATION AND PRELIMINARY GENETIC AND BIOCHEMICAL CHARACTERIZATION OF TEMPERATURE-SENSITIVE MUTANTS OF REOVIRUS

A set of temperature-sensitive mutants of reovirus type 3 has been isolated. The mutagens used were nitrous acid, nitrosoguanidine, and proflavine. Thirty-five mutants have been tested for their ability to recombine following pairwise infection. Five recombination groups have been detected. Twenty-nine mutants fall into one group, four into another, and three mutants recombine efficiently with every other mutant tested. Recombination frequencies are either zero or in excess of 2%. This result supports chemical evidence that the genome of reovirus consists of a number of segments. The mutants have been tested for their ability to induce the formation of virus-specific RNA at the nonpermissive temperature. The classification of mutants according to this criterion agrees exactly with that deduced from recombination tests. © 1969.