The nucleocapsid protein of an enveloped plant virus, Tomato spotted wilt virus, facilitates long-distance movement of Tobacco mosaic virus hybrids
The nucleocapsid protein of an enveloped plant virus, Tomato spotted wilt virus, facilitates long-distance movement of Tobacco mosaic virus hybrids
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有包膜植物病毒番茄斑萎病毒的核衣壳蛋白促进烟草花叶病毒杂交种的长距离移动
DOI：
10.1016/j.virusres.2011.10.006
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发表时间：
2012-01-01
期刊：
影响因子：
5
通讯作者：
Li, Weimin
中科院分区：
文献类型：
--
作者：
Zhang, Yongqiang;Zhang, Chao;Li, Weimin
为了研究番茄斑萎病毒（TSWV）核衣壳（N）蛋白的潜在功能，利用烟草花叶病毒（TMV）复制酶基因表达载体表达了N蛋白的开放阅读框架。在不存在TSWV编码的其他蛋白的情况下，瞬时表达的N蛋白促进了转TMV运动蛋白基因烟草（NB-MP（+））中TMV杂种的长距离运动，从而证明了N蛋白在RNA长距离运动中的功能。去除N端39个氨基酸（N-N Delta 39）、C端26个氨基酸（N-C Delta 26）或两者同时去除（N-N Delta 39 C Delta 26），则长距离运动功能消失，表明N端和C端均起重要作用。与此相反，在位置242和246（N242/262 A），两个关键的氨基酸的同型相互作用的N蛋白的苯丙氨酸丙氨酸的丙氨酸取代，几乎没有影响，这表明N蛋白可以在长距离运动的单体的形式。此外，野生型N和丙氨酸突变体N242/262 A在NB-MP（+）植株和转TMV-MP基因N中几乎不引起局部症状。烟草克桑西缺失突变体N-N Delta 39、N-C Delta 26和N-N Delta 39 C Delta 26在接种的所有叶片中诱导明显的坏死环斑、坏死或褪绿斑症状。在此基础上，对N在TSWV感染过程中的潜在作用进行了讨论。据我们所知，这是第一个报道，包膜植物病毒的N蛋白功能的长途运动。(C)2011 Elsevier B. V.保留所有权利。
To investigate the potential role(s) of the nucleocapsid (N) protein of Tomato spotted wilt virus (TSWV), the open reading frame for the N protein was expressed from a Tobacco mosaic virus (TMV)-based vector encoding only the TMV replicase proteins. In the absence of other TSWV-encoded proteins, the transiently expressed N protein facilitated long-distance movement of the TMV-based hybrids in transgenic Nicotiana benthamiana [NB-MP(+)] expressing movement protein of TMV, thus providing the functional demonstration of the N protein in long-distance RNA movement. Removal of the N-terminal 39 amino acids (N-N Delta 39), the C-terminal 26 amino acids (N-C Delta 26) or both of them (N-N Delta 39C Delta 26) abolished the long-distance movement function, indicating the essential role of both N- and C-terminus. In contrast, alanine substitution of the phenylalanines at positions 242 and 246 (N242/262A), two crucial amino acids for homotypic interaction of the N protein, had little effect, suggesting that the N protein could function in long-distance movement in the form of monomers. In addition, both the wild type N and the alanine mutant N242/262A hardly induced local symptoms in NB-MP(+) plants and TMV-MP transgenic N. tabacum cv. Xanthi. The deletion mutants N-N Delta 39, N-C Delta 26 and N-N Delta 39C Delta 26, however, induced apparent symptoms of necrotic ringspots, necrosis or chlorotic spots in all inoculated leaves. On the basis of these findings, the potential role of N during the TSWV infection was discussed. To our knowledge, this is the first report that the N protein of an enveloped plant virus functioned in long-distance movement. (C) 2011 Elsevier B.V. All rights reserved.