Improvements of the infectivity of in Vitro transcripts from cloned cowpea mosaic virus cDNA: Impact of terminal nucleotide sequences

Biologically Active Transcripts of a Large Satellite RNA from Arabis Mosaic Nepovirus and the Importance of 5' End Sequences for its Replication

“…However, in most recorded instances the biological activity of synthetic transcripts has drastically diminished with increasing numbers of 'extra', non-viral nucleotides at the 5' end of the molecule (Dawson et al, 1986;Janda et al, 1987;Ziegler-Graffet al, 1988;Masuta et al, 1988;Heaton et al, 1989;Eggen et al, 1989). In our experiments by contrast, there was no noticeable difference in the biological activity of MIR and M3R, which have either six or 29 extra nucleotides (derived from the cloning vectors) at the 5' terminus.…”

Biologically active transcripts of alfalfa mosaic virus RNA3

“…According to these results, the infectivity of the transcripts corresponding to RNA3 of AlMV strain S was very sensitive to the number of non-viral nucleotides present at the 5' end, as it was also noted for other plant viruses [8,11,14,15,17,18].…”

“…P3 protein is supposed to be involved in the movement of the virus through the plant [6]. Plant virus infection requires the three genomic RNAs plus RNA4 or the coat protein [7], Development of in vitro run-off transcription systems was used to synthesize infectious RNA transcripts of the plant viruses including beet necrotic yellow vein virus [8,9], brome mosaic virus [IO,1 11, cowpea chlorotic mottle virus [ 121, cowpea mosaic virus [13,14], tobacco mosaic virus [15,16], tomato rattle virus [ 171 and turnip crinkei virus 1181, in order to study the molecular biology of these viruses. Biolo~ic~ly active AlMV RNA4 transcripts have been described [19,20] and we gave evidence that a DNA piasmid carrying RNA3 cDNA of strain S was biologically active at a very low level [21].…”

Infectious transcripts from PCR-amplified broad bean mottle bromovirus cDNA clones and variable nature of leader regions in RNA 3 segment

“…Similar effects were observed in other virus systems having 5' non-viral nucleotides (Janda et al, 1987;Eggen et al, 1989). The repair of incorrect terminal sequences has been reported for all transcript-derived RNA virus infections studied so far (Eggen et al, 1989;Xiong & Lommel, 1991).…”