宿主因子DNAJA1参与甲型流感病毒复制机制的研究

The unusual feature of viral RNA transcription and replication occurring in the nucleus for influenza A virus relies on virus host interaction to a greater extend than other RNA viruses.Moreover,this process is critical in determining virus pathogenicity and virus host-specificity.Through pulldown plus mass spec analysis and siRNA screening, our laboratory newly identified DNAJA1 as a host factor that may regulate influenza A virus replication, which has not been reported before. Our preliminary results have shown that DNAJA1 could positively regulated influenza A virus replication. We also found that it could stimulate viral RNA synthesis in an RNP mini-replicon system. Therefore, based on our expertises on study of host factors and viral RNA polymerase,this project will focus on studying the role of DNAJA1 in all possible aspects invovled in viral RNA synthesis, including vRNP assembly, vRNP transport and RNA polymerase activites, etc. We will further elucidate the molecular mechanisms of DNAJA1 in regulating viral RNA synthesis and to confirm it in in vivo systems. The study will further our understanding of the molecular interactions between host cell and influenza virus, and could ultimately provide new ideas for the development of antiviral drugs.

与其它大部分RNA病毒相比，甲型流感病毒在细胞核中进行病毒RNA转录与复制的过程，使其更依赖病毒与宿主因子相互作用，而且此过程是决定病毒毒力和宿主特异性关键环节之一。本实验室通过前期质谱分析和siRNA筛查，发现宿主因子DNAJA1可能参与了甲型流感病毒的复制，且尚未见报道。我们前期结果表明DNAJA1可正向调控流感病毒在细胞中的复制，而且可在流感病毒RNP小型复制子系统中促进病毒RNA的合成，因此本项目将利用本课题组长期从事流感病毒RNA聚合酶研究的经验和技术平台，从宿主因子可能参与流感病毒RNA合成的多个方面，包括vRNP的装配，vRNP的细胞内转运，以及聚合酶活性等方面进行研究，以阐明DNAJA1调控甲型流感病毒在细胞中的复制的作用机制，并进行各项体内功能验证。该项目的实施有助于我们加深对宿主因子在流感病毒复制的认识，并会为开发新型抗病毒药物提供新思路。

与其它大部分RNA病毒相比，甲型流感病毒在细胞核中进行病毒RNA转录与复制的过程，使其更依赖病毒与宿主因子相互作用，而且此过程是决定病毒毒力和宿主特异性关键环节之一。本实验室通过前期质谱分析和siRNA筛查，发现宿主因子DnaJA1可能参与了甲型流感病毒的复制，且尚未见报道。我们的研究表明DnaJA1可正向调控流感病毒在细胞中的复制，同时发现DnaJA1能够与PB2和PA相互作用，并在体内和体外都能促进RNA的合成。而且流感病毒感染后DnaJA1能够从细胞质向细胞核中转移，而这种转移是伴随着PB1-PA的入核。另外，我们发现DnaJA1促进RNA的合成主要依赖于它的C-末端底物结合结构域而非与Hsp70结合的J结构域。因此我们认为DnaJA1在流感病毒感染后入核，以Hsp70非依赖性方式促进RNA聚合酶活性发挥其调节作用。该项目的实施有助于我们加深对宿主因子在流感病毒复制的认识，并会为开发新型抗病毒药物提供新思路。