陕西杨凌地区TYLCV病毒生物信息学分析研究

Bioinformatic Analysis of TYLCV in Yangling of Shaanxi Province

采集杨凌五泉、揉谷和李台3个番茄主产区表现矮化、黄化及曲叶症状的植株嫩叶，克隆番茄黄化曲叶病毒（TYLCV）基因全长并测序，依次得到病毒分离物TYLCV—SXYL2、TYLCV—SXYL3和TYLCV—SXYL4。通过多序列比对、系统发育树构建及蛋白质结构和理化性质预测等生物信息学方法进行基因组和蛋白质的特征分析，结果表明，杨凌区3个TYLCV分离物之间全长核苷酸相似度为99．3％-99．4％，是不伴随卫星分子的单组分病毒，属TYLCV—IS株系的不同分离物，全长为2781 nt；与山东寿光病毒分离物TYLCV—SDSG亲缘关系最近，相似度为99．6％，与陕西泾阳的分离物TYLCV—SX8相似度为99．1％，与以色列株系TYLCV—IS相似度达97．7％～97．8％；编码6个蛋白质，其中CP、Rep、REn为跨膜蛋白，V2、TrAP、C4为胞内蛋白，Rep和REn为稳定蛋白，CP、V2、TrAP、C4为不稳定蛋白。

We collected the leaves from tomato plants exhibiting stunting, yellowing and curling symptoms in three main tomato production areas Wuquan, Rougu and Litai of Yangling district, and through cloning and sequencing the tomato yellow leaf curl virus （TYLCV） genomes, we got three isolates TYLCV-SXYL2, TYLCV-SXYL3, TYLCV-SXYL4. Bioinformatic approaches including multiple sequence alignment, phylogenetic analysis, protein structure and characteristic prediction were used in genomie and protein analysis, the resuhs showed that, the three isolates, belonged to different isolates of TYLCV-IS strain, were monopartite viruses without satellite, and their full length were 2 781 nt, with similarity degrees ranging from 99.3% to 99.4%. The three Yangling isolates showed closest phylogenetic relationship with TYLCV- SDSG, with similarity degree of 99.6%, and the similarity degree was 99.1% to Jingyang isolate TYLCV-SX8 and 97.7%- 97.8% to Isreal isolate TYLCV-IS. The results of protein structure prediction showed that they encoded six proteins, and CP, Rep, REn had transmembrane structure, while V2, TRAP, C4 were intracellular proteins. Rep and REn were stable proteins, while CP, V2, TRAP, C4 were unstable proteins.