Abstract
S1 nuclease analysis and 3' terminal sequencing of the reovirus genome double-stranded RNAs and in vitro produced viral mRNAs has been used to establish that the viral mRNA is a full length copy of the genome template. Sequence determination at the 3' end of the genome minus strand has by transposition allowed determination of the 5' terminal sequences of the viral mRNAs. In all but one case an AUG codon which could function in initiation of protein synthesis has been found within the determined sequence. The 3' ends of the plus strands from all genome segments were found to have a common sequence. The implications of these results on the mechanism of virus replication are discussed.