title: Expression in transgenic plants of a viral gene product that mediates insect transmission of potyviruses.
abstract: Helper component (HC) is a virus-encoded nonstructural protein that is required for transmission of potyviruses by their aphid vectors. As a prelude to studies on the molecular basis of HC activity, a cDNA clone (pPB-3) was constructed that contained the first three cistrons (34 kDa-HC-42 kDa) of the RNA genome of the potyvirus tobacco vein mottling virus, the first six nucleotides of the adjacent cylindrical inclusion body protein cistron, and a synthetic translation termination codon. This construction was introduced into tobacco cells via a Ti plasmid-based vector. Northern blot analysis of transgenic plants demonstrated the presence of an RNA of the size expected from the construction of pPB-3, and Western blot analysis revealed the presence of a protein that comigrated with authentic HC, indicating that the proteolytic activity necessary to produce mature-sized HC was encoded by pPB-3. The HC produced in the transgenic plants was demonstrated to be active in a virus transmission bioassay with aphids.
authors: Department of Plant Pathology, University of Kentucky, Lexington, 40546-0091.
authors: P H
authors: PH
authors: Berger
authors: A G
authors: AG
authors: Hunt
authors: L L
authors: LL
authors: Domier
authors: G M
authors: GM
authors: Hellmann
authors: Y
authors: Y
authors: Stram
authors: D W
authors: DW
authors: Thornbury
authors: T P
authors: TP
authors: Pirone
mesh_terms: D000818:Animals; D001042:Aphids / Q000382:microbiology*; D001483:Base Sequence; D015870:Gene Expression; D005796:Genes; D005814:Genes, Viral; D008969:Molecular Sequence Data; D010942:Plant Viruses / Q000235:genetics* / Q000502:physiology; D010944:Plants / Q000235:genetics*; D010947:Plants, Toxic; D011401:Promoter Regions, Genetic; D014026:Nicotiana / Q000235:genetics