PDF(Pubmed)
Abstract：
Positive-strand RNA viruses replicate in close association with rearranged intracellular membranes. For hepatitis C virus (HCV) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), these rearrangements comprise endoplasmic reticulum (ER)-derived double membrane vesicles (DMVs) serving as RNA replication sites. Cellular factors involved in DMV biogenesis are poorly defined. Here, we show that despite structural similarity of viral DMVs with autophagosomes, conventional macroautophagy is dispensable for HCV and SARS-CoV-2 replication. However, both viruses exploit factors involved in autophagosome formation, most notably class III phosphatidylinositol 3-kinase (PI3K). As revealed with a biosensor, PI3K is activated in cells infected with either virus to produce phosphatidylinositol 3-phosphate (PI3P) while kinase complex inhibition or depletion profoundly reduces replication and viral DMV formation. The PI3P-binding protein DFCP1, recruited to omegasomes in early steps of autophagosome formation, participates in replication and DMV formation of both viruses. These results indicate that phylogenetically unrelated HCV and SARS-CoV-2 exploit similar components of the autophagy machinery to create their replication organelles.
摘要：
正链RNA病毒与重排的胞内膜紧密相关地复制。对于丙型肝炎病毒（HCV）和严重急性呼吸道综合症冠状病毒2（SARS-CoV-2），这些重排包含内质网（ER）衍生的双膜囊泡（DMV）作为RNA复制位点。参与DMV生物发生的细胞因子定义不清。这里,我们表明，尽管病毒DMV与自噬体的结构相似性，常规巨自噬对于HCV和SARS-CoV-2复制是不必要的。然而,两种病毒都利用参与自噬体形成的因子，最值得注意的是III类磷脂酰肌醇3-激酶(PI3K)。正如生物传感器所揭示的，PI3K在被任一病毒感染的细胞中被激活以产生磷脂酰肌醇3-磷酸(PI3P),而激酶复合物抑制或消耗显著减少复制和病毒DMV形成。PI3P结合蛋白DFCP1，在自噬体形成的早期步骤中募集到ω小体，参与两种病毒的复制和DMV形成。这些结果表明，系统发育无关的HCV和SARS-CoV-2利用自噬机制的相似成分来创建其复制细胞器。
