DExD/H-box RNA解旋酶介导FMDV-IRES依赖性翻译和复制及其在抗病毒免疫中的作用机制

DExD/H-box RNA解旋酶对细胞RNA加工及病毒RNA复制调控至关重要。前期以生物素标记的FMDV-IRES为“诱饵”，通过RNA pulldown技术结合质谱测序后发现，DExD/H-box RNA解旋酶与FMDV-IRES互作。为了进一步探析DExD/H-box RNA解旋酶如何通过与FMDV-IRES互作调控病毒IRES依赖性翻译和复制以及抗病毒免疫，本研究以筛选的DDX23和DDX5为研究对象，利用RNA干扰、RNA-蛋白质互作技术和免疫共沉淀等方法，揭示DDX23和DDX5在病毒复制及如何被FMDV劫持为自身服务的分子机制；同时分别构建IRES、DDX23和DDX5截断体，确定其与FMDV-IRES的互作位点。结果将为阐明DExD/H-box RNA解旋酶重塑RNA结构和调控RNA病毒复制及翻译的机制提供研究基础，也将为开发新型抗病毒药物和高效疫苗种毒改造提供指导。

DExD/H-box RNA helicases play essential roles in RNA processing and viral RNA replication regulation. We recently used biotin-labeled FMDV-IRES as a bait and identified DExD/H-box RNA helicases interacting with FMDV-IRES through RNA-protein pulldown and liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS). To further analyze how the DexD/H-box RNA helicases regulate viral IRES-dependent translation and virus replication as well as antiviral immunity through interaction with FMDV-IRES, we will reveal the role of DexD/H-box RNA helicase in virus replication and the molecular mechanism that FMDV hijacks DDX23 and DDX5 to serve themselves by using RNA interference, RNA-protein interaction techniques and co-immunoprecipitation. Meanwhile, we will further identify the interaction sites of DDX23 and DDX5 with FMDV-IRES by constructing IRES, DDX23 and DDX5 truncated bodies, respectively. These studies will provide a research basis for clarifying the mechanism of DEXD/H-box RNA helicase to reshape RNA and regulate RNA virus replication and translation, and also provide new ideas for the development of new antiviral drugs and genetically modified viruses.