title: Resistance to tobamoviruses in transgenic tobacco plants expressing the coat protein gene of pepper mild mottle virus (Korean isolate).
abstract: Red pepper, one of the most important vegetable crops in Korea, is severely affected by viral diseases causing 20-50% reduction in product yield. A pepper strain of tobacco mosaic virus (TMV-p) is the most common virus in red pepper. To study the molecular structure of the TMV-p virus, we generated cDNA clones of the viral genome. Partial sequencing of a few cDNA clones revealed that TMV-p shares a 98% identity at the nucleotide level with the Spanish isolate of pepper mild mottle virus (PMMV-s). This suggests that TMV-p should be reclassified as the Korean isolate of PMMV (PMMV-k). The coat protein (CP) gene together with the 3' untranslated region of the PMMV-k virus was obtained by reverse transcriptase-polymerase chain reaction (RT-PCR) using oligomers deduced from the sequence of PMMV-s. The sequence analysis of the CP gene and the 3' untranslated region further confirmed that PMMV-k is highly related to PMMV-s. The CP gene and the 3' untranslated region of PMMV-k were cloned into a plant expression vector and the construct was introduced into tobacco plants. The transgenic plants expressing the PMMV-k CP gene were delayed in developing systemic disease or failed to develop symptoms at all after inoculation with PMMV-k. Delay of symptoms was also observed when the plants were inoculated with TMV-OM which shares a 74% homology with PMMV-k in the amino acid sequence of the CP region. In a local lesion host, the CP expressing plants exhibited a greatly reduced number of necrotic lesions as compared to control plants after inoculation with TMV-OM. Our results show that CP-mediated viral resistance is readily applicable in the case of PMMV-k and can provide resistance to other viruses in the tobamovirus group.
authors.affiliation: Department of Life Science, Pohang University of Science and Technology, Korea.
authors.forename: P O
authors.initials: PO
authors.lastname: Lim
authors.forename: J S
authors.initials: JS
authors.lastname: Ryu
authors.forename: H J
authors.initials: HJ
authors.lastname: Lee
authors.forename: U
authors.initials: U
authors.lastname: Lee
authors.forename: Y S
authors.initials: YS
authors.lastname: Park
authors.forename: J M
authors.initials: JM
authors.lastname: Kwak
authors.forename: J K
authors.initials: JK
authors.lastname: Choi
authors.forename: H G
authors.initials: HG
authors.lastname: Nam
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D002213:Capsid / Q000235:genetics; D003001:Cloning, Molecular; D004279:DNA, Viral / Q000235:genetics; D005814:Genes, Viral; D007723:Korea; D008969:Molecular Sequence Data; D030821:Plants, Genetically Modified; D010947:Plants, Toxic; D010957:Plasmids / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid; D017365:Spices / Q000821:virology*; D014026:Nicotiana / Q000235:genetics* / Q000821:virology*; D014027:Tobacco Mosaic Virus / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity; D017898:Tobamovirus / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity*; D014774:Virulence / Q000235:genetics
chemical_list: D004279:DNA, Viral