Nucleotide sequences at the 5′-termini of the alfalfa mosaic virus RNAs and the intercistronic junction in RNA 3

Abstract
Nucleotide sequences at the 5′-termini of the alfalfa mosaic virus genomic RNAs and the intercistronic junction in RNA 3 were deduced and compared to identify possible common recognition signals for replicating enzymes in the corresponsing minus-stranded viral RNAs. Homology between the 5′-terminal sequences is less than 11 nucleotides and no complementarity with the homologous sequence occurring at the 3′-end of the viral RNAs was observed. Homology between the 5′-terminus and intercistronic region in RNA 3 is compatible with the synthesis of subgenomic RNA 4 by internal initiation of transcription on the RNA 3 minusstrands. The sequence around the intercistronic junction can be folded into a very stable secondary structure.