RNAi-Mediated Plant Resistance To Turnip Mosaic Virus

Turnip mosaic virus (TuMV) is the most serious and widely distributed virus in Brassicaceae.Resistance of TuMV in Chinese cabbage is one of our research objectives in the study of geneticbreeding. Resistance gene of TuMV was widely existed, but traditional breeding was longer, and someresistant gene was recessive and it is not easy to use. and also it usually produce variation. We aredevoting to find valid and stable resistant way.The mechanism of resistance by RNAi-mediated post-transcriptional gene silencing (PTGS) iswidely accepted, According to the alignment of122sequences, we choose6k1gene,6k2gene,6k1gene and6k2gene fusion fragment, part of the conserved region of cp gene and construct the fourRNAi vector, Lan-Xiang Feng studied the TuMV isolates separated in Chinese cabbage in Beijing,showed that C1~C5strains exist, And C4was the main strain. The recombinant plasmid vector wastransformed into wild-type Arabidopsis using the Agrobacterium-mediated inflorescence dipping. Theisolate of TuMV-C4was identified and inoculated on the transgenic Arabidopsis to identify theefficiency resistance. We devote to obtain high disease resistance method and lay the foundation forlatter stage of anti-TuMV virus in Chinese cabbageUp to2009, there are122TuMV complete sequences in GeneBank, Complete sequence researchis the basis of the research of spreading and recombination. So we amplified the complete sequence ofBJ-B04、BJ-B05of TuMV, part sequence of C1、C3.and analyze their phylogeny.At present, we had got the following findings:(1)Create a method by multiple one step RT-PCR for rapid detection of Turnip mosaic virus.(2)Grow Chinese cabbage “Si Yue Man” and inoculate isolate of TuMV in proper time to Renewand then collect them.And confirmed that the BJ-B04, the BJ-B05, C1, the C3are BR type.(3)Reverse transcript TuMV and sequencing fragment assembly, align them with other TuMVsequences and construct the phylogenic tree.(4)Select TuMV6k1gene,6k2gene,6k1gene and6k2gene fusion fragment, cp gene of thehighly conserved377bp sequence to construct anti-viral hairpin RNAi vector.(5)The recombinant plasmid was transformed into wild-type Arabidopsis.(6)Identification of the resistance efficiency in transgenic Arabidopsis thaliana and obtain high resistant transgenic line.