The C-terminal end of parainfluenza virus 5 NP protein is important for virus-like particle production and M-NP protein interaction.
The C-terminal end of parainfluenza virus 5 NP protein is important for virus-like particle production and M-NP protein interaction.
复制标题
副流感病毒 5 NP 蛋白的 C 末端对于病毒样颗粒的产生和 M-NP 蛋白相互作用很重要。
DOI：
10.1128/jvi.01885-10
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发表时间：
2010
影响因子：
5.4
通讯作者：
Schmitt,AnthonyP
中科院分区：
文献类型：
--
作者：
Schmitt,PhuongTieu;Ray,Greeshma;Schmitt,AnthonyP
有包膜的病毒颗粒是由感染细胞膜出芽形成的。对于副粘病毒，病毒基质（M）蛋白是病毒组装和出芽的关键驱动因素。然而，其他副粘病毒蛋白，包括糖蛋白、核衣壳（NP或N）蛋白和C蛋白，在某些情况下对颗粒形成也很重要。为了研究NP蛋白在副流感病毒5型（PIV 5）颗粒形成中的作用，分析了NP蛋白截短和置换突变体。NP蛋白C-末端附近的改变完全破坏了其病毒样颗粒（VLP）的生产功能，并显着损害M-NP蛋白的相互作用。产生了具有改变的NP蛋白的重组病毒，并且这些病毒获得了第二位点突变。在Vero细胞中繁殖的重组病毒获得了主要影响病毒聚合酶组分的突变，而在MDBK细胞中繁殖的重组病毒获得了主要影响病毒M蛋白的突变。两种Vero繁殖的病毒获得了相同的突变，V/P（S157 F），以前发现这是由一种充分表征的PIV 5变体P/V-CPI−诱导的病毒基因表达升高的原因。Vero繁殖的病毒引起病毒蛋白质合成增加，并通过直接的细胞-细胞融合通过感染的单层迅速传播，绕过了芽生感染性病毒粒子的需要。Vero和MDBK繁殖的病毒均表现出感染性缺陷和改变的多肽组成，与病毒核糖核蛋白复合物（RNP）掺入出芽病毒体的情况不佳一致。影响M蛋白的第二位点突变在某些情况下恢复了与改变的NP蛋白的相互作用，并改善了VLP的产生。这些结果表明，多种途径可用于副粘病毒克服M-NP蛋白相互作用的缺陷。
Enveloped virus particles are formed by budding from infected-cell membranes. For paramyxoviruses, viral matrix (M) proteins are key drivers of virus assembly and budding. However, other paramyxovirus proteins, including glycoproteins, nucleocapsid (NP or N) proteins, and C proteins, are also important for particle formation in some cases. To investigate the role of NP protein in parainfluenza virus 5 (PIV5) particle formation, NP protein truncation and substitution mutants were analyzed. Alterations near the C-terminal end of NP protein completely disrupted its virus-like particle (VLP) production function and significantly impaired M-NP protein interaction. Recombinant viruses with altered NP proteins were generated, and these viruses acquired second-site mutations. Recombinant viruses propagated in Vero cells acquired mutations that mainly affected components of the viral polymerase, while recombinant viruses propagated in MDBK cells acquired mutations that mainly affected the viral M protein. Two of the Vero-propagated viruses acquired the same mutation, V/P(S157F), found previously to be responsible for elevated viral gene expression induced by a well-characterized variant of PIV5, P/V-CPI−. Vero-propagated viruses caused elevated viral protein synthesis and spread rapidly through infected monolayers by direct cell-cell fusion, bypassing the need to bud infectious virions. Both Vero- and MDBK-propagated viruses exhibited infectivity defects and altered polypeptide composition, consistent with poor incorporation of viral ribonucleoprotein complexes (RNPs) into budding virions. Second-site mutations affecting M protein restored interaction with altered NP proteins in some cases and improved VLP production. These results suggest that multiple avenues are available to paramyxoviruses for overcoming defects in M-NP protein interaction.