Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Nanjing, China.
Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Nanjing, China.
Microb Pathog. 2020 Oct;147:104242. doi: 10.1016/j.micpath.2020.104242. Epub 2020 May 12.
Tembusu virus (TMUV) is a newly emerging flavivirus and has caused significant economic loss to the poultry industry in China. To date, the entry of TMUV into host cells remains poorly understood. Here, the mechanism of TMUV entry into BHK-21 cells was investigated. The depletion of cellular cholesterol by methyl-β-cyclodextrin led to a significant decline in the titers and RNA levels of the infectious TMUV. This reduction was restored by supplementation of exogenous cholesterol. Membrane cholesterol depletion mainly blocked viral internalization but not attachment. However, viral infection was unaffected by genistein treatment or caveolin-1 silencing by small interfering RNA. In addition, clathrin-mediated endocytosis might be utilized in TMUV entry given that the viral infection was inhibited by knockdown of clathrin heavy chain and treatment of chlorpromazine (CPZ). Moreover, the number of internalized virus particles decreased under CPZ treatment. Dynasore inhibited TMUV entry suggesting a role for dynamin. Our results reveal that TMUV entry into BHK-21 cells is dependent on cholesterol, clathrin and dynamin but not caveolae.
腾布苏病毒（TMUV）是一种新出现的黄病毒，已给中国家禽业造成重大经济损失。迄今为止，TMUV 进入宿主细胞的机制仍知之甚少。本研究旨在探讨 TMUV 进入 BHK-21 细胞的机制。用甲基-β-环糊精耗竭细胞胆固醇可显著降低感染性 TMUV 的滴度和 RNA 水平，而外源性胆固醇的补充则可恢复这一降低。膜胆固醇耗竭主要阻断病毒内化，但不阻断病毒附着。然而，用染料木黄酮处理或用小干扰 RNA 沉默窖蛋白-1 对病毒感染没有影响。此外，由于氯丙嗪（CPZ）处理和网格蛋白重链敲低均可抑制病毒感染，因此可能利用网格蛋白介导的内吞作用来进入 TMUV。此外，CPZ 处理后内化的病毒颗粒数量减少。Dynasore 抑制 TMUV 进入提示了 dynamin 的作用。我们的研究结果表明，TMUV 进入 BHK-21 细胞依赖于胆固醇、网格蛋白和 dynamin，但不依赖于 caveolae。
