辣椒轻斑驳病毒湖南分离物的全基因序列测定及结构分析

采自湖南地区的辣椒轻斑驳病毒Pepper mild mottle virus(PMMoV)样品经单斑分离后,根据已经报道的PMMoV序列基因保守区设计6对简并引物,采用片段重叠法和RACE方法扩增、克隆获得一个全长为6 356bp的湖南分离物(PMMoV-HN1,登录号:KP345899)全基因组序列,编码4个蛋白,分别为126kD蛋白(70~3 423nt)、183kD蛋白(70~4 908nt)、28kD蛋白(4 909~5 682nt)和17.5kD蛋白(5 685~6 158nt),5′-非编码区(5′-UTR)和3′-非编码区(3′-UTR)分别含有69和198个碱基,其中5′-UTR存在一个序列为m7G5′pppG的甲基化核苷酸帽子结构。一致性分析发现PMMoV-HN1与PMMoV其他分离物的核酸一致性为94%~99%,编码的氨基酸一致性为94%~99%。全基因组序列系统进化分析表明PMMoV-HN1分离物与中国首次报道的PMMoV-CN分离物亲缘关系最近。本研究是国内报道的第二例PMMoV全基因组序列。

Whole-genome sequence and structural analysis of Pepper mild mottle virus isolate HN1

Pepper samples were collected from Hunan,and identified as Pepper mild mottle virus (PMMoV).According to the previously reported gene conserved regions of PMMoV,six pairs of degenerate primers were designed.The 6 356 bp whole-genome sequence (PMMoV-HN1,accession no.KP345899) was obtained.There were four open reading frames,encoding four proteins,including 126 kD protein (70-3 423 nt),183 kD protein (70-4 908 nt),28 kD protein (4 909-5 682 nt) and 17.5 kD protein (5 685-6 158 nt).The 5'-non-coding region (5'-UTR) and the 3'-non-coding region (3'-UTR) contained 69 and 198 nucleotides,respectively,in which 5'-UTR had a sequence of m7G5'pppG methylation in the nucleotide cap structure.Identity analysis found that the nucleotide identity of PMMoV-HN1 and other PMMoV isolates was 94％-99％,and the identity of the encoded amino acids was 94％-99％.Phylogenetic analysis showed the closest phylogenetic relationships between PMMoV-HN1 and PMMoV-CN.