Holthusen Kirsten, Talaty Pooja, Everly David N
Department of Microbiology and Immunology, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, Illinois, USA.
Department of Microbiology and Immunology, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, Illinois, USA
J Virol. 2015 Jul;89(14):7277-90. doi: 10.1128/JVI.00321-15. Epub 2015 May 6.
Latent membrane protein 1 (LMP1) of Epstein-Barr virus (EBV) induces constitutive signaling in EBV-infected cells to ensure the survival of the latently infected cells. LMP1 is localized to lipid raft domains to induce signaling. In the present study, a genome-wide screen based on bimolecular fluorescence complementation (BiFC) was performed to identify LMP1-binding proteins. Several actin cytoskeleton-associated proteins were identified in the screen. Overexpression of these proteins affected LMP1-induced signaling. BiFC between the identified proteins and LMP1 was localized to lipid raft domains and was dependent on LMP1-induced signaling. Proximity biotinylation assays with LMP1 induced biotinylation of the actin-associated proteins, which were shifted in molecular mass. Together, the findings of this study suggest that the association of LMP1 with lipid rafts is mediated at least in part through interactions with the actin cytoskeleton.
LMP1 signaling requires oligomerization, lipid raft partitioning, and binding to cellular adaptors. The current study utilized a genome-wide screen to identify several actin-associated proteins as candidate LMP1-binding proteins. The interaction between LMP1 and these proteins was localized to lipid rafts and dependent on LMP1 signaling. This suggests that the association of LMP1 with lipid rafts is mediated through interactions with actin-associated proteins.
爱泼斯坦-巴尔病毒（EBV）的潜伏膜蛋白1（LMP1）在EBV感染的细胞中诱导组成性信号传导，以确保潜伏感染细胞的存活。LMP1定位于脂筏结构域以诱导信号传导。在本研究中，基于双分子荧光互补（BiFC）进行了全基因组筛选，以鉴定LMP1结合蛋白。在筛选中鉴定出几种与肌动蛋白细胞骨架相关的蛋白。这些蛋白的过表达影响LMP1诱导的信号传导。鉴定出的蛋白与LMP1之间的BiFC定位于脂筏结构域，并且依赖于LMP1诱导的信号传导。用LMP1进行的邻近生物素化分析诱导了肌动蛋白相关蛋白的生物素化，这些蛋白的分子量发生了变化。总之，本研究结果表明，LMP1与脂筏的结合至少部分是通过与肌动蛋白细胞骨架的相互作用介导的。
LMP1信号传导需要寡聚化、脂筏分区以及与细胞衔接蛋白的结合。当前的研究利用全基因组筛选来鉴定几种与肌动蛋白相关的蛋白作为候选LMP1结合蛋白。LMP1与这些蛋白之间的相互作用定位于脂筏，并且依赖于LMP1信号传导。这表明LMP1与脂筏的结合是通过与肌动蛋白相关蛋白的相互作用介导的。
