山茶褪绿矮缩伴随病毒杭州分离物的序列和进化分析

Sequence and phylogenetic analyses of an isolate of Camellia chlorotic dwarf-associated virus from Hangzhou

双生病毒(Geminivirus)是一类基因组为单链环状DNA的植物病毒,具有孪生的病毒粒子。国际病毒分类委员会(International Committee on Taxonomy of Viruses,ICTV)最新的分类报告将双生病毒分为9个属[1]。随着测序技术的发展,利用小RNA或转录组测序可鉴定植物中的已知和未知病毒,新的双生病毒也不断被发现和鉴定[2]。

Through sequencing and assembly of small RNAs,a Camellia chlorotic dwarf-associated virus(CaCDaV)was identified on a camellia plant showing chlorosis and distorting leaves from Hangzhou(CaCDaV-HZ1).The full genome of CaCDaV-HZ1 was determined and compared with that of a CaCDaV isolate from Chongqing(CaCDaV-CA1).Results showed that they shared 85.7%overall nucleotide sequence identity.Insert and delete mutations were mainly distributed in the non-coding region,whereas the coding regions mainly contained synonymous substitution.All genes except V3 have identical length among the two isolates.Additionally,the small RNA profile of CaCDaV-HZ1 was also analysed and results showed that 24 nt is the major class of viral-derived siRNA indicating that methylation is a major resistance mechanism of camellia plants against geminiviruses.