title: Broad-spectrum transgenic resistance against distinct tospovirus species at the genus level.
abstract: Thrips-borne tospoviruses cause severe damage to crops worldwide. In this investigation, tobacco lines transgenic for individual WLm constructs containing the conserved motifs of the L RNA-encoded RNA-dependent RNA polymerase (L) gene of Watermelon silver mottle virus (WSMoV) were generated by Agrobacterium-mediated transformation. The WLm constructs included: (i) translatable WLm in a sense orientation; (ii) untranslatable WLmt with two stop codons; (iii) untranslatable WLmts with stop codons and a frame-shift; (iv) untranslatable antisense WLmA; and (v) WLmhp with an untranslatable inverted repeat of WLm containing the tospoviral S RNA 3'-terminal consensus sequence (5'-ATTGCTCT-3') and an NcoI site as a linker to generate a double-stranded hairpin transcript. A total of 46.7-70.0% transgenic tobacco lines derived from individual constructs showed resistance to the homologous WSMoV; 35.7-100% plants of these different WSMoV-resistant lines exhibited broad-spectrum resistance against four other serologically unrelated tospoviruses Tomato spotted wilt virus, Groundnut yellow spot virus, Impatiens necrotic spot virus and Groundnut chlorotic fan-spot virus. The selected transgenic tobacco lines also exhibited broad-spectrum resistance against five additional tospoviruses from WSMoV and Iris yellow spot virus clades, but not against RNA viruses from other genera. Northern analyses indicated that the broad-spectrum resistance is mediated by RNA silencing. To validate the L conserved region resistance in vegetable crops, the constructs were also used to generate transgenic tomato lines, which also showed effective resistance against WSMoV and other tospoviruses. Thus, our approach of using the conserved motifs of tospoviral L gene as a transgene generates broad-spectrum resistance against tospoviruses at the genus level.
authors.affiliation: Department of Plant Pathology, National Chung Hsing University, Taichung, Taiwan; Division of Crop Environment, Tainan District Agricultural Research and Extension Station, COA, Tainan, Taiwan.
authors.forename: Jui-Chu
authors.initials: JC
authors.lastname: Peng
authors.affiliation: Department of Plant Pathology, National Chung Hsing University, Taichung, Taiwan; Department of Biotechnology, Asia University, Wufeng, Taichung, Taiwan.
authors.forename: Tsung-Chi
authors.initials: TC
authors.lastname: Chen
authors.affiliation: Agricultural Biotechnology Center, National Chung Hsing University, Taichung, Taiwan; NCHU-UCD Plant and Food Biotechnology Center, National Chung Hsing University, Taichung, Taiwan.
authors.forename: Joseph A J
authors.initials: JA
authors.lastname: Raja
authors.affiliation: Department of Plant Pathology, National Chung Hsing University, Taichung, Taiwan; Agricultural Biotechnology Center, National Chung Hsing University, Taichung, Taiwan.
authors.forename: Ching-Fu
authors.initials: CF
authors.lastname: Yang
authors.affiliation: NCHU-UCD Plant and Food Biotechnology Center, National Chung Hsing University, Taichung, Taiwan.
authors.forename: Wan-Chu
authors.initials: WC
authors.lastname: Chien
authors.affiliation: Department of Plant Pathology, National Chung Hsing University, Taichung, Taiwan.
authors.forename: Chen-Hsuan
authors.initials: CH
authors.lastname: Lin
authors.affiliation: Department of Plant Pathology, National Chung Hsing University, Taichung, Taiwan.
authors.forename: Fang-Lin
authors.initials: FL
authors.lastname: Liu
authors.affiliation: Department of Plant Pathology, National Chung Hsing University, Taichung, Taiwan.
authors.forename: Hui-Wen
authors.initials: HW
authors.lastname: Wu
authors.affiliation: Department of Plant Pathology, National Chung Hsing University, Taichung, Taiwan; Agricultural Biotechnology Center, National Chung Hsing University, Taichung, Taiwan.
authors.forename: Shyi-Dong
authors.initials: SD
authors.lastname: Yeh
mesh_terms: D010935:Plant Diseases / Q000821:virology*; D030821:Plants, Genetically Modified / Q000235:genetics*; D012367:RNA, Viral / Q000235:genetics; D012324:RNA-Dependent RNA Polymerase / Q000235:genetics*; D014026:Nicotiana / Q000235:genetics*; D017865:Tospovirus
chemical_list: D012367:RNA, Viral; D012324:RNA-Dependent RNA Polymerase