巨自噬/自噬和凋亡是宿主细胞对病毒感染的关键相互关联的反应,包括小核糖核酸病毒.这里,小核糖核酸病毒的VP3蛋白被确定触发自噬,自噬通量由TP53-BAD-BAX轴触发。以口蹄疫病毒(FMDV)为模型系统,我们揭示了小核糖核酸病毒如何劫持自噬以支持病毒复制并增强发病机制的新机制。FMDV感染在体内和体外诱导自噬和凋亡。FMDVVP3蛋白促进TP53从细胞核向线粒体的磷酸化和易位,导致BAD介导的细胞凋亡和BECN1介导的自噬。VP3中的氨基酸Gly129对于其与TP53的相互作用是必不可少的,并且对于诱导自噬和凋亡至关重要。VP3诱导的自噬和凋亡都是FMDV复制的关键,while,自噬在VP3介导的发病机制中起着更重要的作用。VP3中Gly129向Ala129的突变消除了VP3的自噬调节功能,从而显着降低了FMDV的病毒复制和发病机理。这表明VP3诱导的自噬有利于病毒复制和发病机理。重要的是,这种Gly是保守的,在各种小核糖核酸病毒中显示出共同的功能。这项研究为开发针对小核糖核酸病毒的广谱抗病毒药物和基因工程减毒疫苗提供了见解。缩写:3-MA,3-甲基腺嘌呤;ATG,自噬相关;BAD,BCL2相关的细胞死亡激动剂;BAK1,BCL2拮抗剂/杀手1;BAX,BCL2关联X,凋亡调节因子;BBC3/PUMA,BCL2结合成分3;BCL2,BCL2凋亡调节因子;BID,BH3相互作用域死亡激动剂;BIP-V5,BAX抑制肽V5;CFLAR/FLIP,CASP8和FADD样细胞凋亡调节因子;CPE,细胞病变效应;CQ,氯喹;CV,柯萨奇病毒;DAPK,死亡相关蛋白激酶;DRAM,DNA损伤调节自噬调节剂;EV71,肠道病毒71型;口蹄疫病毒,口蹄疫病毒;HAV,甲型肝炎病毒;KD,敲低;MAP1LC3/LC3,微管相关蛋白1轻链3;MOI,感染复数;MTOR,雷帕霉素激酶的机制靶点;PML,早幼粒细胞白血病;PV,脊髓灰质炎病毒;SVA,塞内卡谷病毒;TCID50,50%组织培养感染剂量;TOR,雷帕霉素的靶标。TP53/p53,肿瘤蛋白p53;WCL,全细胞裂解物。
Macroautophagy/autophagy and apoptosis are pivotal interconnected host cell responses to viral infection, including picornaviruses. Here, the VP3 proteins of picornaviruses were determined to trigger autophagy, with the autophagic flux being triggered by the TP53-BAD-BAX axis. Using foot-and-mouth disease virus (FMDV) as a model system, we unraveled a novel mechanism of how picornavirus hijacks autophagy to bolster viral replication and enhance pathogenesis. FMDV infection induced both autophagy and apoptosis in vivo and in vitro. FMDV VP3 protein facilitated the phosphorylation and translocation of TP53 from the nucleus into the mitochondria, resulting in BAD-mediated apoptosis and BECN1-mediated autophagy. The amino acid Gly129 in VP3 is essential for its interaction with TP53, and crucial for induction of autophagy and apoptosis. VP3-induced autophagy and apoptosis are both essential for FMDV replication, while, autophagy plays a more important role in VP3-mediated pathogenesis. Mutation of Gly129 to Ala129 in VP3 abrogated the autophagic regulatory function of VP3, which significantly decreased the viral replication and pathogenesis of FMDV. This suggested that VP3-induced autophagy benefits viral replication and pathogenesis. Importantly, this Gly is conserved and showed a common function in various picornaviruses. This study provides insight for developing broad-spectrum antivirals and genetic engineering attenuated vaccines against picornaviruses.Abbreviations: 3-MA, 3-methyladenine; ATG, autophagy related; BAD, BCL2 associated agonist of cell death; BAK1, BCL2 antagonist/killer 1; BAX, BCL2 associated X, apoptosis regulator; BBC3/PUMA, BCL2 binding component 3; BCL2, BCL2 apoptosis regulator; BID, BH3 interacting domain death agonist; BIP-V5, BAX inhibitor peptide V5; CFLAR/FLIP, CASP8 and FADD like apoptosis regulator; CPE, cytopathic effects; CQ, chloroquine; CV, coxsackievirus; DAPK, death associated protein kinase; DRAM, DNA damage regulated autophagy modulator; EV71, enterovirus 71; FMDV, foot-and-mouth disease virus; HAV, hepatitis A virus; KD, knockdown; MAP1LC3/LC3, microtubule associated protein 1 light chain 3; MOI, multiplicity of infection; MTOR, mechanistic target of rapamycin kinase; PML, promyelocytic leukemia; PV, poliovirus; SVA, Seneca Valley virus; TCID50, 50% tissue culture infectious doses; TOR, target of rapamycin. TP53/p53, tumor protein p53; WCL, whole-cell lysate.