西瓜花叶病毒西葫芦分离物的基因组及其侵染性克隆

The genome and infectious clone of watermelon mosaic virus zucchini isolate

西瓜花叶病毒(watermelon mosaic virus,WMV)是危害瓜类作物的一种主要病毒,笔者分析了西葫芦分离物CH99/69的基因组序列和分子变异,构建了具有侵染性的全长cDNA克隆。结果显示,CH99/69分离物基因组全长为10047 nt,与其他分离物的全基因组核苷酸、多聚蛋白核苷酸和多聚蛋白氨基酸的序列一致性分别为81.40%~94.80%、81.40%~94.70%、88.40%~97.20%。基于全基因组序列的系统进化分析显示,CH99/69与中国的Urumqi火参果分离物、WMV-WS西葫芦分离物和法国的WMV-Fr西葫芦分离物亲缘关系较近,它们均聚于Ⅰ组中,而与中国的WMV-Pg人参分离物、WMV-GZca臭椿分离物、hollyhock蜀葵分离物亲缘关系最远。接种试验显示,CH99/69分离物的克隆具有侵染性,能系统侵染甜瓜、西瓜、西葫芦和瓠瓜,经接种产生的病毒后代能够通过摩擦接种进行侵染。

Watermelon mosaic virus(WMV)is one of the most important viruses in cucurbits crops.In this study,the genome sequence of isolate CH99/69 was cloned and analyzed,and its full-length cDNA clone was constructed.The results showed that the genome of isolate CH99/69 was 10047 nt in length,and the identities of the genome nucleotide sequence,the polyprotein nucleotide and amino acid sequence between CH99/69 and other isolates were 81.40%-94.80%,81.40%-94.70%and 88.40%-97.20%.Phylogenetic analysis based on genome sequences showed that CH99/69 was most closely related to isolate Urumqi and WMV-WS from China and WMV-Fr from France,those of which clustered in groupⅠ,but isolates WMV-Pg,WMV-GZca and hollyhock from China were the farthest related.The inoculation showed that the infectious clone was successfully constructed,and it could systematically infect melon,watermelon,zucchini,and bottle gourd.The progeny produced from the clone was infectious by mechanical inoculation.