【作者】 张飞；

【导师】 徐平龙；

【作者基本信息】 浙江大学 ， 细胞生物学， 2021， 博士

【摘要】 戊型肝炎病毒(HEV)是一种全球流行的病原体,在世界范围内每年导致约2000万例感染,300万戊型肝炎病例以及60000人死亡,对孕妇和免疫功能低下的群体尤为危险。然而,目前尚未开发出治疗HEV感染的特异性疗法,临床上通常使用广谱抗病毒药物利巴韦林进行对症治疗。但是利巴韦林治疗效果有限,并且由于其严重的胎儿致畸性孕妇群体禁用,亟需开发安全有效的HEV治疗药物。我们利用前期建立的HEV复制子细胞系对小分子化合物库进行高通量筛选,发现17种HSP90的抑制剂均能较为有效地抑制HEV复制。在机制上,HEV通过劫持宿主蛋白HSP90维持其核心蛋白复制酶(replicase/ORF1)的稳定,构成一类独特的宿主-病原相互作用。使用HSP90抑制剂靶向宿主-HEV相互作用导致ORF1与HSP90解离,促进ORF1发生CHIP介导的K48型泛素化,从而触发ORF1进行一类特殊地泛素蛋白酶体途径处理,特异性地降解其Hel和Rd Rp区域。同时,利用实验室建立的HEV啮齿类动物感染模型,我们发现在体内靶向HSP90能安全有效的抑制基因3型HEV的复制,并且有效地缓解HEV感染造成的肝脏损伤。综上所述,我们的发现不仅阐述了靶向HSP90调控HEV复制的功能和分子机制,也揭示了独特的宿主-HEV相互作用,更为戊型肝炎的治疗提出了潜在的新疗法和分子靶标。此外,本人作为主要研究者探索了经典致癌通路对DNA天然免疫识别的调控。DNA免疫识别不仅介导宿主防御,还在自身免疫疾病、肿瘤免疫和细胞命运决定等生理/病理过程存在重要功能。本人的工作主要集中在HER2靶向调控DNA免疫识别介导的宿主防御和肿瘤免疫的功能探究及部分调控机制的解析。我们的研究揭示了经典致癌通路HER2-AKT调控胞质DNA免疫识别的分子机理,深入探究了其在宿主防御和肿瘤免疫应答中的关键功能,首次提出了经典致癌通路基于DNA识别的肿瘤免疫调控功能。更多还原

【Abstract】 Hepatitis E virus(HEV)is a globally prevalent pathogen,which annually results in 20 million infections,3 million hepatitis E cases,and 60,000 fatalities worldwide,endangering especially the pregnant women and immunocompromised individuals.At present,there is no HEV-specific therapeutics,and ribavirin,the broad-spectrum antiviral drug,frequently leads to treatment failure.In addition,the pregnant women are not eligible for ribavirin treatment due to fetal teratogenicity.Therefore,a safe and HEV-specific antiviral medicine is urgingly needed.Here,we performed an unbiased screening on HEV replicon,which intriguingly hit 17 compounds targeting the HSP90.Unexpectedly,we found that HEV forming a unique host-virus interaction by hijacking the host key protein HSP90 to maintain the stability of its core protein ORF1.HSP90 targeting released viral replicase(ORF1)from the ORF1-HSP90 complex,marked ORF1 for CHIP-mediated K48 ubiquitination,and triggered the unprocessed ORF1 for a unique and rapid ubiquitin-proteasomal processing to delete the putative helicase and Rd Rp domains and degradation.Notably,the anti-HEV strategy targeting the ORF1-HSP90 interaction was safe,considerably efficient,and substantially prevented the liver damage in HEV-inflicted rodents,as proofed in a preclinical trial in gerbils with chronic infection of human genotype 3 HEV.Collectively,our findings describe a critical mechanism of HEV in host-HEV interactions,and propose promising therapeutics by targeting this weakness for the treatment of deleterious hepatitis E diseases.In addition,I contributed the study to elucidate the role of a classic oncogenic pathway,i.e.HER2-AKT signaling,in innate DNA sensing mediated by the c GASSTING mechanism.Innate DNA sensing mediates host defense and plays the important roles in autoimmunity,anti-tumor immunity,and cell fate determination.We suggest at the first time in this study the key functions of HER2-AKT signlaing in host defense and anti-tumor immunity via effective control of c GAS-STING signaling,realized by an intriguing molecular mechanism.更多还原