title: Sequences required for self-catalysed cleavage of the satellite RNA of tobacco ringspot virus.
abstract: The satellite RNA of tobacco ringspot virus (sTobRV) undergoes self-catalysed cleavage during replication. A plasmid for in vitro expression of sTobRV has been constructed and used to obtain a library of mutagenized sTobRV sequences. Screening of these mutants has allowed precise definition of the sequences required for (+) and (-) strand cleavage. The sequences and RNA structures associated with cleavage of each strand differ markedly. Cleavage of the (+) strand requires those sequences flanking the site for cleavage to form a 'hammerhead' domain, similar to those found in other satellite and viroid RNA. In contrast, cleavage of the (-) strand requires only a small region of 12 nucleotides (nt) at the site of cleavage, and a sequence of 55 nt positioned elsewhere in the molecule. Comparison with a closely related satellite suggests that a novel RNA structure may be involved in (-) strand cleavage.
authors.affiliation: CSIRO Division of Plant Industry, Canberra, Australia.
authors.forename: J
authors.initials: J
authors.lastname: Haseloff
authors.forename: W L
authors.initials: WL
authors.lastname: Gerlach
mesh_terms: D001483:Base Sequence; D002384:Catalysis; D005814:Genes, Viral; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D010942:Plant Viruses / Q000235:genetics* / Q000502:physiology; D010957:Plasmids; D016337:RNA, Catalytic; D012335:RNA, Ribosomal / Q000235:genetics* / Q000378:metabolism; D012367:RNA, Viral / Q000235:genetics* / Q000378:metabolism; D012526:Satellite Viruses / Q000235:genetics* / Q000502:physiology; D012689:Sequence Homology, Nucleic Acid; D013329:Structure-Activity Relationship; D014779:Virus Replication
chemical_list: D016337:RNA, Catalytic; D012335:RNA, Ribosomal; D012367:RNA, Viral