Significant differences in nucleocapsid morphology within the Paramyxoviridae
Significant differences in nucleocapsid morphology within the Paramyxoviridae
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DOI：
10.1099/0022-1317-83-8-1831
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发表时间：
2002-08-01
影响因子：
3.8
通讯作者：
Yeo, RP
中科院分区：
文献类型：
--
作者：
Bhella, D;Ralph, A;Yeo, RP
利用重组杆状病毒在昆虫细胞中表达副粘病毒科3个属代表病毒的核衣壳蛋白。含有RNA的结构在形态上看起来与病毒核衣壳相同，他们被分离出来，然后在透射电子显微镜下成像。对这些图像的分析显示，在所调查的属中，核衣壳的形态存在显著差异，最明显的是副粘病毒亚科和肺炎病毒亚科的病毒之间。螺旋螺距测量表明，麻疹病毒(MV，副粘病毒亚科的一种麻疹病毒)N蛋白产生的螺旋采用多种构象，具有不同程度的灵活性，而类风湿病毒5型(SV5，副粘病毒亚科)产生的螺旋结构更坚硬，节距分布不均匀。呼吸道合胞病毒(RSV，肺炎病毒亚科)产生的核衣壳比MV和SV5的核衣壳窄得多，节距比MV的最延伸形式长。除了螺旋核衣壳外，还产生了环结构，图像分析表明，由MV N蛋白组装的环由13个亚基组成。这与此前报道的仙台病毒核衣壳每轮有13(.)07个亚基的报道一致。然而，已确定SV5亚核衣壳环有14个亚基，而来自截然不同的RSV核衣壳的环被发现主要包含10个亚基。
Nucleocapsid (N) proteins from representative viruses of three genera within the Paramyxoviridae were expressed in insect cells using recombinant baculoviruses. RNA-containing structures, which appear morphologically identical to viral nucleocapsids, were isolated and subsequently imaged under a transmission electron microscope. Analysis of these images revealed marked differences in nucleocapsid morphology among the genera investigated, most notably between viruses of the Paramyxovirinae and the Pneumovirinae subfamilies. Helical pitch measurements were made, revealing that measles virus (MV, a Morbillivirus within the subfamily Paramyxovirinae) N protein produces helices that adopt multiple conformations with varying degrees of flexibility, while that of the Rubulavirus simian virus type 5 (SV5, subfamily Paramyxovirinae) produces more rigid structures with a less heterogeneous pitch distribution. Nucleocapsids produced by respiratory syncytial virus (RSV, subfamily Pneumovirinae) appear significantly narrower than those of MV and SV5 and have a longer pitch than the most extended form of MV. In addition to helical nucleocapsids, ring structures were also produced, image analysis of which has demonstrated that rings assembled from MV N protein consist of 13 subunits. This is consistent with previous reports that Sendai virus nucleocapsids have 13(.)07 subunits per turn. It was determined, however, that SV5 subnucleocapsid rings have 14 subunits, while rings derived from the radically different RSV nucleocapsid have been found to contain predominantly 10 subunits.