Determinants of Disease Phenotype Differences Caused by Closely-Related Isolates of Begomovirus Betasatellites Inoculated with the Same Species of Helper Virus.
Determinants of Disease Phenotype Differences Caused by Closely-Related Isolates of Begomovirus Betasatellites Inoculated with the Same Species of Helper Virus.
复制标题
同种辅助病毒接种贝戈莫病毒β卫星密切相关分离株引起疾病表型差异的决定因素
DOI：
10.3390/v7092853
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发表时间：
2015-09-14
期刊：
影响因子：
--
通讯作者：
Qian Y
中科院分区：
文献类型：
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作者：
Zhang J;Dang M;Huang Q;Qian Y
中国番茄黄卷叶病毒（TYLCCNV）是一种与不同betassatellite相关的单株begomavirus。在这项研究中，我们研究了两种不同的番茄黄卷叶中国betasatellite （TYLCCNB）分离株，以确定在密切相关的betasatellite之间诱导特征表型差异需要病毒基因组的哪些特征。与TYLCCNV共接种烟草植株和番茄植株时，TYLCCNB-Y25在所有寄主上仅诱导叶片卷曲，而TYLCCNB-Y10还诱导叶片变黄、叶脉变黄和茎部变形。进一步的实验表明，TYLCCNB-Y25的βC1与TYLCCNB-Y10在症状诱导和转录调节方面存在差异。通过交换βC1基因或βC1上游200 nt部分启动子样片段构建杂交卫星。感染实验表明，带有完整TYLCCNB-Y10 βC1基因的TYLCCNB-Y25杂种能够诱导静脉变黄、茎部变形、大小和数量减少。与完整的TYLCCNB-Y25 βC1基因杂交的TYLCCNB-Y10只产生卷曲叶片。相比之下，部分启动子样区域交换的TYLCCNB-Y25和TYLCCNB-Y10杂种对野生型betasat卫星诱导的表型影响不大。进一步实验表明，携带TYLCCNB-Y10 βC1 c端区的TYLCCNB-Y25杂种诱导了TYLCCNB-Y10样症状。这些发现表明βC1蛋白是主要的症状决定因素，βC1的c端区域在症状诱导中起重要作用。
Tomato yellow leaf curl China virus (TYLCCNV) is a monopartite begomovirus associated with different betasatellites. In this study, we investigate two different isolates of Tomato yellow leaf curl China betasatellite (TYLCCNB) to determine what features of the viral genome are required for induction of characteristic phenotypic differences between closely-related betasatellite. When co-agroinoculated with TYLCCNV into Nicotiana spp. and tomato plants, TYLCCNB-Y25 induced only leaf curling on all hosts, while TYLCCNB-Y10 also induced enations, vein yellowing, and shoot distortions. Further assays showed that βC1 of TYLCCNB-Y25 differs from that of TYLCCNB-Y10 in symptom induction and transcriptional modulating. Hybrid satellites were constructed in which the βC1 gene or 200 nt partial promoter-like fragment upstream of the βC1 were exchanged. Infectivity assays showed that a TYLCCNB-Y25 hybrid with the intact TYLCCNB-Y10 βC1 gene was able to induce vein yellowing, shoot distortions, and a reduced size and number of enations. A TYLCCNB-Y10 hybrid with the intact TYLCCNB-Y25 βC1 gene produced only leaf curling. In contrast, the TYLCCNB-Y25 and TYLCCNB-Y10 hybrids with swapped partial promoter-like regions had little effect on the phenotypes induced by wild-type betasatellites. Further experiments showed that the TYLCCNB-Y25 hybrid carrying the C-terminal region of TYLCCNB-Y10 βC1 induced TYLCCNB-Y10-like symptoms. These findings indicate that the βC1 protein is the major symptom determinant and that the C-terminal region of βC1 plays an important role in symptom induction.