Chan Zuckerberg Biohub, San Francisco, CA 94158, USA.
Gladstone Institutes, San Francisco, CA 94158, USA.
Cell Rep. 2021 Mar 16;34(11):108859. doi: 10.1016/j.celrep.2021.108859.
Hepatitis A virus (HAV) is a positive-sense RNA virus causing acute inflammation of the liver. Here, using a genome-scale CRISPR screen, we provide a comprehensive picture of the cellular factors that are exploited by HAV. We identify genes involved in sialic acid/ganglioside biosynthesis and members of the eukaryotic translation initiation factor complex, corroborating their putative roles for HAV. Additionally, we uncover all components of the cellular machinery for UFMylation, a ubiquitin-like protein modification. We show that HAV translation specifically depends on UFM1 conjugation of the ribosomal protein RPL26. Furthermore, we find that components related to the yeast Trf4/5-Air1/2-Mtr4 polyadenylation (TRAMP) complex are required for viral translation independent of controlling viral poly(A) tails or RNA stability. Finally, we demonstrate that pharmacological inhibition of the TRAMP-like complex decreases HAV replication in hepatocyte cells and human liver organoids, thus providing a strategy for host-directed therapy of HAV infection.
甲型肝炎病毒（HAV）是一种正链 RNA 病毒，可导致肝脏急性炎症。在这里，我们使用基因组规模的 CRISPR 筛选，提供了 HAV 利用的细胞因子的全面图片。我们鉴定了参与唾液酸/神经节苷脂生物合成的基因和真核翻译起始因子复合物的成员，证实了它们对 HAV 的假定作用。此外，我们发现了细胞泛素样蛋白修饰 UFMylation 的所有组成部分。我们表明，HAV 翻译特异性依赖于核糖体蛋白 RPL26 的 UFM1 缀合。此外，我们发现与酵母 Trf4/5-Air1/2-Mtr4 多聚腺苷酸化（TRAMP）复合物相关的成分在不控制病毒多聚（A）尾巴或 RNA 稳定性的情况下，对病毒翻译是必需的。最后，我们证明了 TRAMP 样复合物的药理学抑制可降低肝细胞和人肝类器官中的 HAV 复制，从而为 HAV 感染的宿主定向治疗提供了一种策略。
