title: 3'-terminal nucleotide sequences important for the accumulation of cowpea mosaic virus M-RNA.
abstract: The location of nucleotide sequences important in determining the extent of cowpea mosaic virus M-RNA accumulation in cowpea protoplasts has been analyzed by deletion mutagenesis of full-length cDNA clones from which infectious transcripts can be produced in vitro. The results suggest that cis-acting sequences which direct replication of M-RNA by B-RNA-encoded products are located within the 5'-terminal 524 nucleotides and the 3'-terminal 151 nucleotides. RNA secondary structure predictions for the 3'-terminal 151 nucleotides of both genomic RNAs (Eggen et al. (1989) Virology 173, 456-464) indicate that the terminal nucleotides form a stable secondary structure composed of a Y-shaped stem-loop and a simple A-U-rich stem-loop. The latter structure has been implicated in B-RNA replication. We have examined the role of the Y-shaped structure in M-RNA accumulation by site-directed mutagenesis of putative base-pairing combinations in the two minor stems. The results suggest that efficient replication is dependent on the formation of both of these minor stem structures.
authors.affiliation: Department of Virus Research, John Innes Institute, Norwich, United Kingdom.
authors.forename: J B
authors.initials: JB
authors.lastname: Rohll
authors.forename: C L
authors.initials: CL
authors.lastname: Holness
authors.forename: G P
authors.initials: GP
authors.lastname: Lomonossoff
authors.forename: A J
authors.initials: AJ
authors.lastname: Maule
mesh_terms: D001483:Base Sequence; D015152:Blotting, Northern; D002213:Capsid / Q000235:genetics; D007887:Fabaceae; D008969:Molecular Sequence Data; D009029:Mosaic Viruses / Q000235:genetics* / Q000378:metabolism; D016297:Mutagenesis, Site-Directed; D009690:Nucleic Acid Conformation; D009838:Oligodeoxyribonucleotides; D010946:Plants, Medicinal; D017354:Point Mutation; D012367:RNA, Viral / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015183:Restriction Mapping; D017384:Sequence Deletion
chemical_list: D009838:Oligodeoxyribonucleotides; D012367:RNA, Viral