Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, Texas, USA.
Nat Chem Biol. 2011 Sep 11;7(10):712-9. doi: 10.1038/nchembio.645.
A chemical genetics approach was taken to identify inhibitors of NS1, a major influenza A virus virulence factor that inhibits host gene expression. A high-throughput screen of 200,000 synthetic compounds identified small molecules that reversed NS1-mediated inhibition of host gene expression. A counterscreen for suppression of influenza virus cytotoxicity identified naphthalimides that inhibited replication of influenza virus and vesicular stomatitis virus (VSV). The mechanism of action occurs through activation of REDD1 expression and concomitant inhibition of mammalian target of rapamycin complex 1 (mTORC1) via TSC1-TSC2 complex. The antiviral activity of naphthalimides was abolished in REDD1(-/-) cells. Inhibition of REDD1 expression by viruses resulted in activation of the mTORC1 pathway. REDD1(-/-) cells prematurely upregulated viral proteins via mTORC1 activation and were permissive to virus replication. In contrast, cells conditionally expressing high concentrations of REDD1 downregulated the amount of viral protein. Thus, REDD1 is a new host defense factor, and chemical activation of REDD1 expression represents a potent antiviral intervention strategy.
采用化学遗传学方法鉴定了 NS1 的抑制剂，NS1 是流感 A 病毒的主要毒力因子，可抑制宿主基因表达。对 20 万个合成化合物进行高通量筛选，发现了可逆转 NS1 介导的宿主基因表达抑制的小分子。针对抑制流感病毒细胞毒性的反筛选鉴定出了抑制流感病毒和水疱性口炎病毒（VSV）复制的萘啶酰胺。作用机制是通过激活 REDD1 表达并通过 TSC1-TSC2 复合物同时抑制雷帕霉素靶蛋白复合物 1（mTORC1）。REDD1(-/-)细胞中萘啶酰胺的抗病毒活性被消除。病毒抑制 REDD1 表达会导致 mTORC1 通路的激活。REDD1(-/-)细胞通过 mTORC1 激活过早地上调病毒蛋白，并且对病毒复制具有易感性。相比之下，条件性表达高浓度 REDD1 的细胞会下调病毒蛋白的量。因此，REDD1 是一种新的宿主防御因子，而 REDD1 表达的化学激活代表了一种有效的抗病毒干预策略。
