UBIQUITIN AND CELLULAR FACTORS IN CORONAVIRUS ASSEMBLY

冠状病毒引起鸟类和动物的呼吸道和胃肠道疾病。这些 RNA病毒在遗传上是可变的，可以迅速进化感染人类，有时 导致严重的急性呼吸道疾病。冠状病毒在它们的 通过涉及细胞内病毒形成的策略从细胞中组装和分泌 也许还有通往外部环境的新的贩运路线。进一步理解 这些晚期感染事件将确定治疗干预的策略。我们 已经发现一种原型小鼠肝炎冠状病毒在组装时被抑制， 和/或分泌阶段。 我们假设抑制机制涉及细胞中泛素的耗竭， 蛋白酶体抑制剂的已知作用，因为我们发现病毒E蛋白 在病毒分泌的中心，在两个赖氨酸残基上被泛素化。我们的目标是 以确定致病性人类冠状病毒是否对 蛋白酶体抑制剂，然后解决是否泛素结合的E蛋白， 对冠状病毒形态发生或排出细胞至关重要。我们的实验将 特异性评价抑制剂和泛素作用位点是否在病毒上 分泌阶段，并将解决新的假设，泛素修饰直接 将充满病毒的细胞器运输到释放病毒货物的细胞表面。 我们的研究结果将揭示新的细胞生物学特征的囊泡形成和细胞器 运输，并将告知我们在晚些时候阻止冠状病毒的潜力 感染阶段。

Coronaviruses cause respiratory and gastrointestinal diseases in birds and animals. These RNA viruses are genetically variable and can rapidly evolve to infect humans, sometimes causing severe acute respiratory disease. The coronaviruses are set apart in their assembly and secretion from cells by a strategy involving intracellular virus formation and perhaps novel trafficking routes to the outside environment. Further understanding of these late infection events will identify strategies for therapeutic intervention. We have discovered that a prototype mouse hepatitis coronavirus is inhibited at the assembly and / or secretion stages by very low nontoxic concentrations of a proteasome inhibitor. We hypothesize that the inhibitory mechanism involves ubiquitin depletion from cells, a known effect of proteasome inhibitors, because we discovered that the viral E proteins that are central to virus secretion are ubiquitinated on two lysine residues. Our aims are to determine whether pathogenic human coronaviruses are similarly hypersensitive to proteasome inhibitors and then address whether the ubiquitin conjugation of E proteins is central to coronavirus morphogenesis or expulsion out of cells. Our experiments will specifically evaluate whether the locus of inhibitor and ubiquitin action are at the virus secretion stages and will address the novel hypothesis that ubiquitin modifications direct the trafficking of virus-filled organelles to cell surfaces where the virus cargo is liberated. Our findings will reveal novel cell biological features of vesicle formation and organelle transport and will also inform us about the potential to thwart coronaviruses at late infection stages.