We had isolated and identified two Cucumber mosaic virus (CMV) isolates, the CMV red bean (CMV-RB) isolate and the CMV pea (CMV-P1) isolate. CMV-RB induces necrotic local lesions on inoculated leaves of broad bean, pe...We had isolated and identified two Cucumber mosaic virus (CMV) isolates, the CMV red bean (CMV-RB) isolate and the CMV pea (CMV-P1) isolate. CMV-RB induces necrotic local lesions on inoculated leaves of broad bean, pea, cowpea and bean, and could not infect these hosts systemically. However, CMV-P1 was able to infect these legumes systemically. To study the difference of pathogenic-ity on the legumes induced by these two CMV isolates, the full-length infectious cDNA clones of CMV-Fny, which induced similar symptoms as CMV-RB in the four legumes, were used. The 243 nucleotides fragment, which encodes highly conserved GDD amino acid motif on 2a replicase gene of CMV-Fny RNA2, was replaced with that of CMV-P1. The constructed chimeric virus FP could infect these legumes systemically. The exchange of this region changes the virus symptoms on the legumes, indicating that this 243 nucleotides fragment has major effect on pathogenicity of CMV on the legumes.展开更多
基金This work was supported by the National Key Basic Research and Development Program (Grant No. G2000016204), the Teaching and Research Award Program for Outstanding Teachers in Higher Education Institutes of Ministry of Education (MOE) the National Outs
文摘We had isolated and identified two Cucumber mosaic virus (CMV) isolates, the CMV red bean (CMV-RB) isolate and the CMV pea (CMV-P1) isolate. CMV-RB induces necrotic local lesions on inoculated leaves of broad bean, pea, cowpea and bean, and could not infect these hosts systemically. However, CMV-P1 was able to infect these legumes systemically. To study the difference of pathogenic-ity on the legumes induced by these two CMV isolates, the full-length infectious cDNA clones of CMV-Fny, which induced similar symptoms as CMV-RB in the four legumes, were used. The 243 nucleotides fragment, which encodes highly conserved GDD amino acid motif on 2a replicase gene of CMV-Fny RNA2, was replaced with that of CMV-P1. The constructed chimeric virus FP could infect these legumes systemically. The exchange of this region changes the virus symptoms on the legumes, indicating that this 243 nucleotides fragment has major effect on pathogenicity of CMV on the legumes.