Nucleotide sequences from tomato leaf curl viruses from different countries: evidence for three geographically separate branches in evolution of the coat protein of whitefly-transmitted geminiviruses.
Nucleotide sequences from tomato leaf curl viruses from different countries: evidence for three geographically separate branches in evolution of the coat protein of whitefly-transmitted geminiviruses.
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来自不同国家的番茄曲叶病毒的核苷酸序列：烟粉虱传播的双生病毒外壳蛋白进化过程中三个地理上独立的分支的证据。
DOI：
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发表时间：
1995
影响因子：
3.8
通讯作者：
B. Harrison
中科院分区：
文献类型：
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作者：
Yiguo Hong;B. Harrison
对从印度南部分离的番茄曲叶双生病毒（ITmLCV; 2749 nt）的含外壳蛋白（CP）基因的环状DNA分子和从尼日利亚和沙特阿拉伯两个地区分离的番茄黄化曲叶双生病毒的CP基因进行了测序。ITmLCV DNA具有与旧大陆其他粉虱传播双生病毒（WTG）的DNA-A中相同的ORF排列和大基因间隔区中相同的重复模式。然而，ITmLCV DNA的序列及其预测的翻译产物的序列与其他WTG的序列有很大不同，包括从印度北方的番茄植株中获得的一个分离株。比较这里推导的4个CP序列与先前研究的18个WTG的CP序列表明，它们之间的关系可以用一棵树来表示，该树有三个分支，与植物宿主物种无关，但分别包含来自美洲、非洲到中东和亚洲到澳大利亚的病毒。这表明，WTG CP进化进行了沿着不同的路径在这三个主要地区，WTG已经适应了新的主机在每个区域。事实上，在不同大陆引起番茄植物类似疾病的病毒分离物，除了少数例外，并不密切相关，并应被视为单独的物种。
The coat protein (CP) gene-containing circular DNA molecule of an isolate of tomato leaf curl geminivirus (ITmLCV; 2749 nt) obtained from southern India, and the CP genes of tomato yellow leaf curl geminivirus isolates from Nigeria and two regions of Saudia Arabia were sequenced. ITmLCV DNA had the same arrangement of ORFs, and the same pattern of repeats in the large intergenic region as is found in in DNA-A of other whitefly-transmitted geminivirus (WTGs) from the Old World. However, the sequence of ITmLCV DNA and the sequences of its predicted translation products differed substantially from those of other WTGs, including one isolate obtained from a tomato plant in northern India. Comparison of the four CP sequences deduced here with those of 18 WTGs previously studied indicated that their relationships can be represented by a tree with three branches that are unrelated to plant host species but which contains viruses from the Americas, Africa to the Middle East, and Asia to Australia, respectively. It is suggested that WTG CP evolution has proceeded along different paths in these three main regions, and that WTGs have adapted freely to new hosts in each region. Indeed, the virus isolates causing similar diseases of tomato plants in the different continents are, with few exceptions, not closely related and warrant recognition as separate species.