The extracellular domain of La Crosse virus G1 forms oligomers and undergoes pH-dependent conformational changes.
The extracellular domain of La Crosse virus G1 forms oligomers and undergoes pH-dependent conformational changes.
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拉克罗斯病毒 G1 的胞外结构域形成寡聚物并经历 pH 依赖性构象变化。
DOI：
10.1006/viro.1996.0596
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发表时间：
1996
期刊：
影响因子：
3.7
通讯作者：
González-Scarano,F
中科院分区：
文献类型：
--
作者：
Pekosz,A;González-Scarano,F
La Crosse病毒G1糖蛋白在病毒与敏感细胞的结合以及随后病毒与细胞膜的融合中发挥关键作用。在重组杆状病毒系统中制备的G1糖蛋白(SG1)的可溶性形式模仿La Crosse病毒的细胞结合模式并抑制La Crosse病毒的感染(A.Pekoszzet al.，Virology214,339-348,1995)，推测是通过竞争细胞受体来实现的，这一发现表明，SG1可以在没有G2的情况下执行一些功能，G2是两种布尼亚病毒糖蛋白中较小的一个。我们已经进行了实验来确定SG1是否以低聚物的形式存在，以及它是否经历了与融合相关的构象变化(F.Gonzalez-Scarano，Virology140,209-216,1985)。我们的结果表明，SG1和天然G1在暴露于酸性环境后都经历了类似的构象变化，通过与单抗的反应来检测。此外，利用化学交联法，这两种蛋白质都被检测为寡聚体(最有可能是二聚体)。蔗糖密度梯度分析证实SG1以单体和寡聚形式存在。这些结果表明，在没有跨膜区和胞浆尾区的情况下，分离的G1糖蛋白可以发生pH依赖的构象变化，并且糖蛋白的胞外部分可以寡聚。
The La Crosse virus G1 glycoprotein plays a critical role in virus binding to susceptible cells and in the subsequent fusion of viral and cellular membranes. A soluble form of the G1 glycoprotein (sG1) prepared in a recombinant baculovirus system mimics the cell-binding pattern of La Crosse virus and inhibits La Crosse virus infection (A. Pekoszet al., Virology214, 339–348, 1995), presumably by competing for a cellular receptor, a finding that implies that sG1 can perform some functions absent G2, the smaller of the two bunyavirus glycoproteins. We have performed experiments to determine whether sG1 is present as an oligomer and whether it undergoes the conformational changes associated with fusion (F. Gonzalez-Scarano,Virology140, 209–216, 1985). Our results indicate that both sG1 and native G1 undergo similar changes in conformation after exposure to an acidic environment, as detected by reactivity with monoclonal antibodies. Furthermore, using chemical cross-linking, both proteins were detected as oligomers (most likely dimers). Sucrose density gradient analysis of sG1 verified that it was present in monomeric and oligomeric forms. These results demonstrate that the isolated G1 glycoprotein can undergo a pH-dependent change in conformation in the absence of its transmembrane and cytoplasmic tail domains and that the extracellular portion of the glycoprotein can oligomerize.