The nucleotide sequence of satellite tobacco necrosis virus strain C and helper-assisted replication of wild-type and mutant clones of the virus.
The complete nucleotide sequence of satellite tobacco necrosis virus strain C (STNV-C) was determined. The genome has a similar overall organization to two STNV isolates studied previously but differs significantly from them in the secondary structure of the translated and untranslated regions (UTRs). STNV-C RNA is naturally uncapped and contains 1221 nt: 101 nt in the 5' UTR, 606 nt in the capsid protein (CP) coding region and 514 nt in the 3' UTR. Using the known sequences of STNV-C and tobacco necrosis virus strain D (TNV-D) RNAs, full-length cDNA clones of both RNAs were constructed. Synthetic transcripts derived from STNV-C cDNA clones only replicated in plants and protoplasts when co-inoculated with TNV-D transcripts. A number of mutant clones in both the 3' and the 5' STNV-C RNA UTRs were constructed which disrupted putative cis-acting elements recognized by helper virus polymerase. Deletion analysis revealed an essential requirement of all 3' and 5' proximal sequences in the STNV-C UTRs for replication. However, an internal region in the 3' UTR could be deleted without loss of infectivity. Likewise, the entire STNV-C CP-encoding region could be deleted and replaced with a marker gene of a similar size without loss of transcript accumulation in plants.
Bringloe
D H
DH
Biology Department, Imperial College of Science, Technology and Medicine, London, UK.
Gultyaev
A P
AP
Pelpel
M
M
Pleij
C W
CW
Coutts
R H
RH
D001483:Base Sequence; D004279:DNA, Viral; D006378:Helper Viruses / Q000235:genetics / Q000502:physiology*; D008969:Molecular Sequence Data; D009154:Mutation; D009690:Nucleic Acid Conformation; D010947:Plants, Toxic; D012367:RNA, Viral / Q000737:chemistry; D012526:Satellite Viruses / Q000235:genetics* / Q000502:physiology*; D017423:Sequence Analysis, RNA; D014026:Nicotiana / Q000821:virology*; D014779:Virus Replication
D004279:DNA, Viral; D012367:RNA, Viral