新城疫病毒(NDV)的转录和复制严格依赖于病毒核糖核蛋白(RNP)复合物,由病毒NP组成,P,L和RNA。然而,目前尚不清楚其他病毒非RNP蛋白是否参与病毒自我调节的过程.在这项研究中,我们使用小基因组(MG)系统来鉴定病毒非RNP蛋白V的调节作用,M,W,F和HN其中,与其他蛋白质相比,V显着降低了MG编码的报道分子活性,并抑制了病毒mRNA和cRNA的合成。Further,V与NP相互作用。在NP-P-L共转染的细胞中,V的残基W195中的突变减少了V-NP相互作用并抑制了包涵体(IB)的形成。此外,建立了高毒力菌株F48E9的反向遗传系统。突变体rF48E9-VW195R增加了病毒复制并明显增加了IB形成。体内实验表明rF48E9-VW195R降低了毒力并延迟了死亡时间。总的来说,结果表明,W195突变体V的V-NP相互作用减少,调节病毒RNA合成,IB形成,病毒复制和致病性。这项研究提供了对副粘病毒中非RNP蛋白自我调节的见解。
The transcription and replication of the Newcastle disease virus (NDV) strictly rely on the viral ribonucleoprotein (RNP) complex, which is composed of viral NP, P, L and RNA. However, it is not known whether other viral non-RNP proteins participate in this process for viral self-regulation. In this study, we used a minigenome (MG) system to identify the regulatory role of the viral non-RNP proteins V, M, W, F and HN. Among them, V significantly reduced MG-encoded reporter activity compared with the other proteins and inhibited the synthesis of viral mRNA and cRNA. Further, V interacted with NP. A mutation in residue W195 of V diminished V-NP interaction and inhibited inclusion body (IB) formation in NP-P-L-cotransfected cells. Furthermore, a reverse-genetics system for the highly virulent strain F48E9 was established. The mutant rF48E9-VW195R increased viral replication and apparently enhanced IB formation. In vivo experiments demonstrated that rF48E9-VW195R decreased virulence and retarded time of death. Overall, the results indicate that the V-NP interaction of the W195 mutant V decreased, which regulated viral RNA synthesis, IB formation, viral replication and pathogenicity. This study provides insight into the self-regulation of non-RNP proteins in paramyxoviruses.