侵染云南烟草的粉虱传双生病毒卫星分子基因组结构特征

Structure Characterization of Genome of Whitefly-transmitted Geminivirus Associated Satellites DNA β Infecting Tobacco in Yunnan Province

对侵染云南烟草的粉虱传双生病毒致病性相关分子DNAβ进行PCR扩增和克隆。对9份采自不同时间和地区的样品中的DNAβ分子的全基因组序列分析发现,9个DNAβ都具有典型双生病毒DNAβ卫星分子的基因组结构特征:在互补链上编码1个大小约为118个氨基酸的βC1蛋白,含有1个卫星分子保守区(Satellite conserved region,SCR)和1个A富含区。核苷酸同源性分析显示,9个分离物的DNAβ分子中,7个分离物的DNAβ属于TYLCCNV伴随的DNAβ分子,1个属于MYVYNV伴随的DNAβ分子,2个属于TYLCTHV伴随的DNAβ分子,1个属于TbCSV伴随的DNAβ分子。系统进化分析发现,这些DNAβ卫星分子具有明显的种类和地理分布差异,但没有因寄主和采集时间的不同而表现出明显的差异。

The satellites DNA β molecules of Whitefly-transmitted geminiviras were amplified and cloned in tobacco samples. 9 samples were selected for amplifying and sequencing the full-length DNAβ according to different areas, date and host. On the basis of nncleotide sequence analysis, all DNAβ molecules contained three conserved region： an A-rich region, a sequence-conserved region （SCR） and a complementary-sense ORFs termed βC1. Sequence similarity analysis showed 9 DNA 13 were grouped into 4 type according to the full-length DNA 13 ： 7 molecules belong to TYLCCNV-associated DNA beta, 1 molecule belongs to MYVYNV-associated DNA beta, 2 molecules belong to TYLCTHV-associated DNA beta and 1 molecule belongs to TbCSV-associated DNA beta. Phylogenetic analysis indicated that all molecules were distinguished by geographic origin and types, rather than host and date.