title: Protein expression strategies in Tobacco necrosis virus-D.
abstract: Tobacco necrosis virus (TNV-D) has a plus-strand RNA genome that is neither 5' capped nor 3' poly-adenylated. Instead, it utilizes a 3' cap-independent translational enhancer (3'CITE) located in its 3' untranslated region (UTR) for translation of its proteins. We have examined the protein expression strategies used by TNV-D and our results indicate that: (i) a base pairing interaction between conserved ACCA and UGGU motifs in the genomic 5'UTR and 3'CITE, respectively, is not required for efficient plant cell infection, (ii) similar potential 5'UTR-3'CITE interactions in the two viral subgenomic mRNAs are not needed for efficient translation of viral proteins in vitro, (iii) a small amount of capsid protein is translated from the viral genome by a largely 3'CITE-independent mechanism, (iv) the larger of two possible forms of capsid protein is efficiently translated, and (v) p7b is translated from subgenomic mRNA1 by a leaky scanning mechanism.
authors.affiliation: Department of Biology, York University, Toronto, Ontario, Canada M3J 1P3.
authors.forename: Tamari
authors.initials: T
authors.lastname: Chkuaseli
authors.affiliation: Department of Biology, York University, Toronto, Ontario, Canada M3J 1P3.
authors.forename: Laura R
authors.initials: LR
authors.lastname: Newburn
authors.affiliation: Department of Biology, York University, Toronto, Ontario, Canada M3J 1P3.
authors.forename: David
authors.initials: D
authors.lastname: Bakhshinyan
authors.affiliation: Department of Biology, York University, Toronto, Ontario, Canada M3J 1P3. Electronic address: kawhite@yorku.ca.
authors.forename: K Andrew
authors.initials: KA
authors.lastname: White
mesh_terms: D020121:5' Untranslated Regions; D001483:Base Sequence; D018553:Cucumis sativus / Q000821:virology; D015967:Gene Expression Regulation, Viral; D016679:Genome, Viral; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D010935:Plant Diseases / Q000821:virology; D014176:Protein Biosynthesis; D012367:RNA, Viral / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D019183:Tombusviridae / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D014764:Viral Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism
chemical_list: D020121:5' Untranslated Regions; D012367:RNA, Viral; D014764:Viral Proteins
keywords: Cap-independent translation; Carmovirus; IRES; Leaky scanning; Necrovirus; Plant virus; RNA structure; RNA virus; Readthrough; Tombusviridae