Tijms Marieke A, Snijder Eric J
Molecular Virology Laboratory, Department of Medical Microbiology, Center of Infectious Diseases, Leiden University Medical Center, LUMC E4-P, PO Box 9600, 2300 RC Leiden, The Netherlands.
J Gen Virol. 2003 Sep;84(Pt 9):2317-2322. doi: 10.1099/vir.0.19297-0.
Non-structural protein 1 (nsp1), the N-terminal subunit of the replicase polyprotein of the arterivirus Equine arteritis virus (EAV), is essential for viral subgenomic mRNA synthesis, but fully dispensable for genome replication. However, at the molecular level, the role of nsp1 in EAV subgenomic mRNA synthesis is poorly understood. A yeast two-hybrid screen did not reveal interactions between EAV nsp1 and other viral non-structural proteins or the nucleocapsid protein, although both nsp1 and the nucleocapsid protein were found to form homomers. Subsequently, a yeast two-hybrid screen of a HeLa cell cDNA library was performed using nsp1 as bait. Remarkably, this analysis revealed (potential) interactions between EAV nsp1 and factors that are involved in host cell transcriptional regulation. The interaction of nsp1 with one of these proteins, p100, a transcription co-activator that also interacts with regulatory proteins of other viruses, was confirmed by mutual co-immunoprecipitation from lysates of EAV-susceptible mammalian cells.
非结构蛋白1（nsp1）是动脉炎病毒马动脉炎病毒（EAV）复制酶多聚蛋白的N端亚基，对病毒亚基因组mRNA合成至关重要，但对基因组复制完全 dispensable 。然而，在分子水平上，nsp1在EAV亚基因组mRNA合成中的作用尚不清楚。酵母双杂交筛选未揭示EAV nsp1与其他病毒非结构蛋白或核衣壳蛋白之间的相互作用，尽管发现nsp1和核衣壳蛋白均形成同源寡聚体。随后，以nsp1为诱饵对HeLa细胞cDNA文库进行酵母双杂交筛选。值得注意的是，该分析揭示了EAV nsp1与参与宿主细胞转录调控的因子之间的（潜在）相互作用。通过从EAV易感哺乳动物细胞裂解物中进行相互免疫共沉淀，证实了nsp1与其中一种蛋白p100的相互作用，p100是一种转录共激活因子，也与其他病毒的调控蛋白相互作用。
