Hsia Ho-Pan, Yang Yin-Hua, Szeto Wun-Chung, Nilsson Benjamin E, Lo Chun-Yeung, Ng Andy Ka-Leung, Fodor Ervin, Shaw Pang-Chui
Centre for Protein Science and Crystallography, School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China.
Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom.
PLoS One. 2018 Jan 16;13(1):e0191226. doi: 10.1371/journal.pone.0191226. eCollection 2018.
The influenza virus RNA genome is transcribed and replicated in the context of the viral ribonucleoprotein (vRNP) complex by the viral RNA polymerase. The nucleoprotein (NP) is the structural component of the vRNP providing a scaffold for the viral RNA. In the vRNP as well as during transcription and replication the viral polymerase interacts with NP but it is unclear which parts of the polymerase and NP mediate these interactions. Previously the C-terminal '627' domain (amino acids 538-693) of PB2 was shown to interact with NP. Here we report that a fragment encompassing amino acids 146-185 of NP is sufficient to mediate this interaction. Using NMR chemical shift perturbation assays we show that amino acid region 601 to 607 of the PB2 '627' domain interacts with this fragment of NP. Substitutions of these PB2 amino acids resulted in diminished RNP activity and surface plasmon resonance assays showed that amino acids D605 was essential for the interaction with NP and V606 may also play a partial role in the interaction. Collectively these results reveal a possible interaction surface between NP and the PB2 subunit of the RNA polymerase complex.
流感病毒RNA基因组在病毒核糖核蛋白（vRNP）复合物的背景下由病毒RNA聚合酶进行转录和复制。核蛋白（NP）是vRNP的结构成分，为病毒RNA提供支架。在vRNP中以及转录和复制过程中，病毒聚合酶与NP相互作用，但尚不清楚聚合酶和NP的哪些部分介导了这些相互作用。此前已表明PB2的C端“627”结构域（氨基酸538 - 693）与NP相互作用。在此我们报告，包含NP氨基酸146 - 185的片段足以介导这种相互作用。使用核磁共振化学位移扰动分析，我们表明PB2“627”结构域的氨基酸区域601至607与NP的该片段相互作用。这些PB2氨基酸的替换导致RNP活性降低，表面等离子体共振分析表明氨基酸D605对于与NP的相互作用至关重要，V606在相互作用中可能也起部分作用。这些结果共同揭示了NP与RNA聚合酶复合物的PB2亚基之间可能的相互作用表面。
