Nucleotide sequences of 5' and 3' non-coding regions of pepper mild mottle virus strain S RNA.

The nucleotide sequences of the 5' and 3' non-coding regions of pepper mild mottle virus strain S (PMMV-S) RNA were determined; they are more like corresponding sequences of tomato mosaic virus (ToMV) RNA than those of any other tobamovirus reported so far. The 5' leader contains a 68 nucleotide guanosine-free sequence which differs in several nucleotides from the corresponding sequences in genomic RNA of tobacco mosaic virus (TMV) and ToMV. The messenger activity of PMMV-S RNA in vitro and the polypeptide translation products made were similar to those of TMV RNA. It therefore seems unlikely that qualitative or quantitative differences in translation in vivo account for the milder symptoms induced by PMMV-S, and its lesser replication, than TMV. The 3' non-coding region of PMMV-S RNA is 199 nucleotides long and can be folded into the same secondary structure as the RNA of other tobamoviruses.