福建地区草莓斑驳病毒全基因组测序和分子变异分析

Strawberry Mottle Virus Isolated in Fujian:Complete Genome Sequence and Molecular Variation

为了深入解析草莓斑驳病毒(strawberry mottle virus,SMoV)的分子变异以及遗传多样性,采用小RNA高通量测序结合RACE和RT-PCR技术获得了福建地区SMoV基因组全长序列。SMoV基因组RNA1和RNA2分别为7034 nt和6354 nt,均含有1个ORF,分别编码多聚蛋白P1和P2;SMoV福建分离物同其他15个SMoV分离物的同源性分析表明,RNA1核苷酸和多聚蛋白P1氨基酸同源性分别为79.2%~96.8%和89.0%~99.5%;RNA2核苷酸和多聚蛋白P2氨基酸同源性分别为77.9%~97.8%和89.9%~98.9%。SMoV福建分离物各编码蛋白同其他15个SMoV分离物的同源性分析表明,仅病毒基因组连接蛋白最为保守,其他各蛋白核苷酸序列和氨基酸序列变异均较大。福建分离物和中国部分分离物聚在一个大分支上,和中国分离物DGHY3亲缘关系最近。SMoV中国福建分离物的基因组结构与其他分离物相一致,其核苷酸序列和氨基酸序列分子变异较大,并且和中国其他分离物具有较丰富的遗传多样性,在进化上有一定的地理相关性。

To analyze the molecular variation and genetic diversity of strawberry mottle virus(SMoV), highthroughput sequencing(HTS), RT-PCR combined with 3’ and 5’ RACE were used to obtain the complete genome sequence of SMoV Fujian isolate. The results showed that RNA1 and RNA2 of SMoV consisted of7034 nt and 6354 nt, and both contained one large ORF, encoding polyprotein P1 and P2, respectively. The homology of SMoV Fujian isolate and other fifteen SMoV isolates was analyzed. The nucleotide and amino acid homology of RNA1 was 79.2%-96.8% and 89.0%-99.5%, respectively. The nucleotide and amino acid homology of RNA2 was 77.9%-97.8% and 89.9%-98.9%, respectively. Among the encoding proteins of SMoV Fujian isolate, only the viral genome-linked protein was the most conserved, the nucleotide and amino acid sequences of other proteins were variable compared to other 15 SMoV isolates. The Fujian isolate and some other Chinese isolates are in a big branch, and most closely related to Chinese isolate DGHY3. The genomic structure of Fujian isolate is consistent with other SMoV isolates. Nucleotide sequence and amino acid sequence of Fujian isolate have obvious molecular variation. Fujian isolate and the other Chinese isolates have abundant diversity, and there is geographical relativity in evolution.