Terminal structure of reovirus RNAs

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 atthe 3 ' end of the genome minus strand has by transposition allowed determination f 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