title: cis-Acting core RNA elements required for negative-strand RNA synthesis and cap-independent translation are separated in the 3'-untranslated region of Red clover necrotic mosaic virus RNA1.
abstract: The genome of Red clover necrotic mosaic virus (RCNMV) is positive-sense and divided into RNA1 and RNA2. RNA1 has a translation enhancer element (3' TE-DR1) in the 3' untranslated region (UTR) that substitutes for a 5' cap. In this study, we determined the regions required for cap-independent translation and RNA synthesis in the 3' UTR of RNA1 using a cell-free extract of evacuolated BY-2 protoplasts (BYL) and by an assay in BY-2 protoplasts. The use of capped viral RNA transcripts in the BYL system allowed us to distinguish the effects of introduced mutations on cap-independent translation and negative-strand RNA synthesis of RNA1. We found that the core RNA element of 3' TE-DR1 essential for cap-independent translation of RNA1 is dispensable for negative-strand RNA synthesis. Thus, cis-acting RNA elements essential for cap-independent translation are separated from those required for negative-strand RNA synthesis in the 3' UTR of RCNMV RNA1.
authors.affiliation: Laboratory of Plant Pathology, Graduate School of Agriculture, Kyoto University, Sakyo-Ku, Kitashirakawa, Kyoto 606-8502, Japan.
authors.forename: Hiro-Oki
authors.initials: HO
authors.lastname: Iwakawa
authors.forename: Masanori
authors.initials: M
authors.lastname: Kaido
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Mise
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Okuno
mesh_terms: D020413:3' Untranslated Regions / Q000737:chemistry / Q000235:genetics*; D001483:Base Sequence; D008969:Molecular Sequence Data; D009154:Mutation; D009690:Nucleic Acid Conformation; D014176:Protein Biosynthesis; D012367:RNA, Viral / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics*; D012045:Regulatory Sequences, Nucleic Acid; D014026:Nicotiana; D019183:Tombusviridae / Q000235:genetics* / Q000502:physiology; D014158:Transcription, Genetic; D014764:Viral Proteins / Q000096:biosynthesis
chemical_list: D020413:3' Untranslated Regions; D012367:RNA, Viral; D014764:Viral Proteins