论文信息：Qi Yue, Qianlong Yu, Qi Yang, Ye Xu, Ya Guo, Gary W. Blissard, Zhaofei Li . Distinct roles of cellular ESCRT-I and ESCRT-III proteins in efficient entry and egress of budded virions of Autographa californica multiple nucleopolyhedrovirus.Journal of Virology(2018)92(1).
JCR分区Q1，中科院大类二区Top, IF=4.368
论文摘要：The endosomal sorting complex required for transport (ESCRT) machin-ery is necessary for budding of many enveloped viruses. Recently, it was demon-strated that Vps4, the key regulator for recycling of the ESCRT-III complex, is re-quired for efficient infection by the baculovirus Autographa californica multiple nucleopolyhedrovirus (AcMNPV). However, ESCRT assembly, regulation, and function are complex, and little is known regarding the details of participation of specific ESCRT complexes in AcMNPV infection. In this study, the core components of ESCRT-I (Tsg101 and Vps28) and ESCRT-III (Vps2B, Vps20, Vps24, Snf7, Vps46, and
Vps60) were cloned from Spodoptera frugiperda. Using a viral complementation system and RNA interference (RNAi) assays, we found that ESCRT-I and ESCRT-III
complexes are required for efficient entry of AcMNPV into insect cells. In cells knocking down or overexpressing dominant negative (DN) forms of the compo-
nents of ESCRT-I and ESCRT-III complexes, entering virions were partially trapped within the cytosol. To examine only egress, cells were transfected with the double-
stranded RNA (dsRNA) targeting an individual ESCRT-I or ESCRT-III gene and viral bacmid DNA or viral bacmid DNA that expressed DN forms of ESCRT-I and
ESCRT-III components. We found that ESCRT-III components (but not ESCRT-I components) are required for efficient nuclear egress of progeny nucleocapsids.
In addition, we found that several baculovirus core or conserved proteins (Ac11, Ac76, Ac78, GP41, Ac93, Ac103, Ac142, and Ac146) interact with Vps4 and com-
ponents of ESCRT-III. We propose that these viral proteins may form an “egress complex” that is involved in recruiting ESCRT-III components to a virus egress
domain on the nuclear membrane.
