Potyvirus helper component-proteinase and coat protein (CP) have coordinated functions in virus-host interactions and the same CP motif affects virus transmission and accumulation
Potyvirus helper component-proteinase and coat protein (CP) have coordinated functions in virus-host interactions and the same CP motif affects virus transmission and accumulation
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DOI：
10.1099/0022-1317-80-5-1133
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发表时间：
1999-05-01
影响因子：
3.8
通讯作者：
Valkonen, JPT
中科院分区：
文献类型：
--
作者：
Andrejeva, J;Puurand, Ü;Valkonen, JPT
利用马铃薯A型马铃薯Y病毒（PVA-B11）的感染性cDNA克隆，研究了与PVA-B11和PVA-U分离物生物学差异相关的辅助蛋白酶（HC-Pro）和外壳蛋白（CP）的氨基酸差异。用PVA-U的CP基因替换PVA-B11的整个CP基因使烟草中的病毒积累减少5倍，达到PVA-U的水平。相比之下，在PVA-B11 HC-Pro中同时进行的四个氨基酸取代（根据PVA-U HC-Pro）使病毒积累增加2至4倍。在CP N末端的单个取代（S7 G）使病毒积累减少10倍，但恢复PVA-B11的蚜虫传播性。B11中HC-Pro的同时突变和CP的替换延迟了烟草的系统运动，限制了马铃薯的细胞间运动。这些结果意味着协调功能的HC-Pro和CP的积累和运动的PVA，因为两个基因的同时突变所造成的表型效应是不同的预期的“总和”的表型变化观察到的突变后，只有一个基因的时间。
Amino acid differences between helper component-proteinase (HC-Pro) and coat protein (CP) that are putatively associated with biological differences between isolates PVA-B11 and PVA-U of potato A potyvirus (PVA) were studied using an infectious cDNA clone of PVA-B11. Replacement of the entire CP gene of PVA-B11 with the CP gene of PVA-U reduced virus accumulation in tobacco 5-fold, to the level of PVA-U. In contrast, four simultaneous amino acid substitutions made in PVA-B11 HC-Pro (according to PVA-U HC-Pro) increased virus accumulation 2- to 4-fold. A single substitution (S7G) at the CP N terminus reduced virus accumulation 10-fold, but restored aphid-transmissibility of PVA-B11. Simultaneous mutation of HC-Pro and replacement of CP in B11 delayed systemic movement in tobacco and limited cell-to-cell movement in potato. These results imply coordinated functions of HC-Pro and CP in accumulation and movement of PVA, because the phenotypic effects caused by simultaneous mutation of the two genes were different from the expected 'sum' of phenotypic changes observed following mutation of only one gene at a time.