Tobacco mosaic virus induces the synthesis of a family of 3′ coterminal messenger RNAs and their complements

At least eight 3′ coterminal RNA species, which may act as messenger RNAs, are synthesized during infection of tobacco (Nicotiana tabacum) by tobacco mosaic virus. These RNAs vary in length from 700 nucleotides to the genomic RNA of 6400 nucleotides and include the mRNAs for the coat protein and the 30,000 M_r protein. RNAs that contain the viral origin of assembly are packaged and may be recovered from preparations of the virus. Complementary strand RNAs corresponding to each of the messengers are also synthesized during infection. It is proposed that the coterminal RNAs are synthesized during tobacco mosaic virus infection by a mechanism involving incomplete transcription of the viral RNA into negative strands that are subsequently transcribed to produce messenger RNAs.