Xiao Xia, Lei Xiaobo, Zhang Zhenzhen, Ma Yijie, Qi Jianli, Wu Chao, Xiao Yan, Li Li, He Bin, Wang Jianwei
MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China.
Department of Microbiology and Immunology, College of Medicine, University of Illinois, Chicago, Illinois, USA.
J Virol. 2017 Sep 12;91(19). doi: 10.1128/JVI.00791-17. Print 2017 Oct 1.
Like other enteroviruses, enterovirus 71 (EV71) relies on phosphatidylinositol 4-kinase IIIβ (PI4KB) for genome RNA replication. However, how PI4KB is recruited to the genome replication sites of EV71 remains elusive. Recently, we reported that a host factor, ACBD3, is needed for EV71 replication by interacting with viral 3A protein. Here, we show that ACBD3 is required for the recruitment of PI4KB to RNA replication sites. Overexpression of viral 3A or EV71 infection stimulates the interaction of PI4KB and ACBD3. Consistently, EV71 infection induces the production of phosphatidylinositol-4-phosphate (PI4P). Furthermore, PI4KB, ACBD3, and 3A are all localized to the viral-RNA replication sites. Accordingly, PI4KB or ACBD3 depletion by small interfering RNA (siRNA) leads to a reduction in PI4P production after EV71 infection. I44A or H54Y substitution in 3A interrupts the stimulation of PI4KB and ACBD3. Further analysis suggests that stimulation of ACBD3-PI4KB interaction is also important for the replication of enterovirus 68 but disadvantageous to human rhinovirus 16. These results reveal a mechanism of enterovirus replication that involves a selective strategy for recruitment of PI4KB to the RNA replication sites. Enterovirus 71, like other human enteroviruses, replicates its genome within host cells, where viral proteins efficiently utilize cellular machineries. While multiple factors are involved, it is largely unclear how viral replication is controlled. We show that the 3A protein of enterovirus 71 recruits an enzyme, phosphatidylinositol 4-kinase IIIβ, by interacting with ACBD3, which alters cellular membranes through the production of a lipid, PI4P. Consequently, the viral and host proteins form a large complex that is necessary for RNA synthesis at replication sites. Notably, PI4KB-ACBD3 interaction also differentially mediates the replication of enterovirus 68 and rhinovirus 16. These results provide new insight into the molecular network of enterovirus replication.
与其他肠道病毒一样，肠道病毒71型（EV71）的基因组RNA复制依赖于磷脂酰肌醇4激酶IIIβ（PI4KB）。然而，PI4KB如何被招募到EV71的基因组复制位点仍不清楚。最近，我们报道了一种宿主因子ACBD3，它通过与病毒3A蛋白相互作用参与EV71复制。在此，我们表明ACBD3是PI4KB招募到RNA复制位点所必需的。病毒3A的过表达或EV71感染会刺激PI4KB与ACBD3的相互作用。同样，EV71感染会诱导磷脂酰肌醇-4-磷酸（PI4P）的产生。此外，PI4KB、ACBD3和3A都定位于病毒RNA复制位点。因此，小干扰RNA（siRNA）介导的PI4KB或ACBD3缺失会导致EV71感染后PI4P产生减少。3A中的I44A或H54Y替代会中断对PI4KB和ACBD3的刺激。进一步分析表明，ACBD3-PI4KB相互作用的刺激对肠道病毒68型的复制也很重要，但对人鼻病毒16型不利。这些结果揭示了肠道病毒复制的一种机制，该机制涉及将PI4KB招募到RNA复制位点的选择性策略。肠道病毒71型与其他人类肠道病毒一样，在宿主细胞内复制其基因组，病毒蛋白在其中有效利用细胞机制。虽然涉及多种因素，但病毒复制如何被控制在很大程度上尚不清楚。我们表明，肠道病毒71型的3A蛋白通过与ACBD3相互作用招募一种酶——磷脂酰肌醇4激酶IIIβ，后者通过产生脂质PI4P改变细胞膜。因此，病毒和宿主蛋白形成一个大复合物，这是复制位点RNA合成所必需的。值得注意的是，PI4KB-ACBD3相互作用也以不同方式介导肠道病毒68型和鼻病毒16型的复制。这些结果为肠道病毒复制的分子网络提供了新的见解。
