Vesicular stomatitis virus G protein transmembrane region is crucial for the hemi-fusion to full fusion transition
Vesicular stomatitis virus G protein transmembrane region is crucial for the hemi-fusion to full fusion transition
复制标题
水泡性口炎病毒G蛋白跨膜区对于半融合到全融合的转变至关重要
DOI：
10.1038/s41598-018-28868-y
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发表时间：
2018-07-13
影响因子：
4.6
通讯作者：
Shi, Lei
中科院分区：
文献类型：
--
作者：
Ci, Yali;Yang, Yang;Shi, Lei
病毒融合蛋白对包膜病毒感染至关重要。这些蛋白介导病毒包膜和宿主细胞膜之间的融合，将病毒基因组释放到细胞中。水疱性口炎病毒G （VSV G）蛋白是一种典型的III型病毒融合蛋白。为了研究VSV - G蛋白介导的膜融合机制，我们建立了不同荧光蛋白标记细胞的细胞-细胞融合系统。利用该系统，我们对VSV G介导的细胞融合进行了实时记录和定量分析。我们发现VSV G介导的细胞-细胞融合所需的时间尺度约为1-2分钟。接下来，我们用其他融合蛋白的跨膜区取代VSV G蛋白的跨膜区，专门研究了跨膜区在膜融合中的功能。在细胞-细胞融合实验中，TM区域的替换显著损害了VSV G蛋白的功能，降低了VSV G介导的慢病毒和重组VSV感染的效率。进一步的实验表明，TM区在半融合到完全融合的过程中发挥了作用。TM区域内的几个残基被确定为膜融合的重要残基。总的来说，我们的发现揭示了TM区域在VSV - G介导的病毒融合中的重要功能。
Viral fusion proteins are essential for enveloped virus infection. These proteins mediate fusion between the virus envelope and host cellular membrane to release the viral genome into cells. Vesicular stomatitis virus G (VSV G) protein is a typical type III viral fusion protein. To study the mechanism of VSV G protein mediated membrane fusion, we set up a cell-cell fusion system in which cells are marked by different fluorescent proteins. Taking advantage of this system, we performed real-time recording and quantitative analysis of the cell fusion mediated by VSV G. We found that the time scale required for VSV G mediated cell-cell fusion was approximately 1-2 minutes. Next, we specifically examined the function of the transmembrane (TM) region of VSV G protein in membrane fusion by replacing the TM region with those of other fusion proteins. The TM region replacements dramatically impaired VSV G protein function in the cell-cell fusion assay and diminished VSV G mediated lentivirus and recombinant VSV infection efficiency. Further experiments implied that the TM region played a role in the transition from hemi-fusion to full fusion. Several residues within the TM region were identified as important for membrane fusion. Overall, our findings unraveled the important function of the TM region in VSV G mediated viral fusion.