Intra-strain biological and epidemiological characterization of plum pox virus
Intra-strain biological and epidemiological characterization of plum pox virus
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DOI：
10.1111/mpp.12908
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发表时间：
2020-01-24
影响因子：
4.9
通讯作者：
Yamaji, Yasuyuki
中科院分区：
文献类型：
--
作者：
Maejima, Kensaku;Hashimoto, Masayoshi;Yamaji, Yasuyuki
李痘病毒（Plum pox virus， PPV）是造成严重经济损失的重要植物病毒之一。迄今为止，基于10种具有部分可分化生物学特性的单系菌株的定义的菌株分型是用于PPV流行病学特征的唯一方法。然而，阐明种群或分离株之间株内生物学变异的遗传决定因素仍然是病毒流行病学的一个相关但未经研究的方面。在这项研究中，基于210株日本和47株非日本PPV-Dideron (D)菌株的完整核苷酸序列信息，我们在PPV-D基因组中确定了5个阳性选择位点。其中，分子研究表明，病毒复制酶2635位的氨基酸取代与病毒滴度和系统水平上的竞争相关，表明2635位氨基酸与蚜虫的传播效率和症状严重程度有关。祖先基因组序列的估计表明，2,635个氨基酸位置的替换是可逆的，并且是日本两个遗传上不同的PPV-D群体之一所特有的。可逆氨基酸的进化可能有助于病毒种群的传播。这项研究首次从基因组角度深入了解了猪流行性感冒的进化流行病学，该研究基于归因于正选择的株内生物学变异。
Plum pox virus (PPV) is one of the most important plant viruses causing serious economic losses. Thus far, strain typing based on the definition of 10 monophyletic strains with partially differentiable biological properties has been the sole approach used for epidemiological characterization of PPV. However, elucidating the genetic determinants underlying intra-strain biological variation among populations or isolates remains a relevant but unexamined aspect of the epidemiology of the virus. In this study, based on complete nucleotide sequence information of 210 Japanese and 47 non-Japanese isolates of the PPV-Dideron (D) strain, we identified five positively selected sites in the PPV-D genome. Among them, molecular studies showed that amino acid substitutions at position 2,635 in viral replicase correlate with viral titre and competitiveness at the systemic level, suggesting that amino acid position 2,635 is involved in aphid transmission efficiency and symptom severity. Estimation of ancestral genome sequences indicated that substitutions at amino acid position 2,635 were reversible and peculiar to one of two genetically distinct PPV-D populations in Japan. The reversible amino acid evolution probably contributes to the dissemination of the virus population. This study provides the first genomic insight into the evolutionary epidemiology of PPV based on intra-strain biological variation ascribed to positive selection.