Conformational Changes in Sindbis Virus Induced by Decreased pH Are Revealed by Small-Angle Neutron Scattering
Conformational Changes in Sindbis Virus Induced by Decreased pH Are Revealed by Small-Angle Neutron Scattering
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DOI：
10.1128/jvi.06569-11
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发表时间：
2012-02-01
影响因子：
5.4
通讯作者：
Brown, Dennis T.
中科院分区：
文献类型：
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作者：
He, Lilin;Piper, Amanda;Brown, Dennis T.
甲病毒，如辛德毕斯病毒，在暴露于低pH时经历三维结构的显著变化，并且这种暴露可以建立允许病毒膜与细胞质膜在返回到中性pH时融合的条件。虽然辛德毕斯病毒进入脊椎动物或无脊椎动物细胞不需要暴露于低pH，在低pH下发生的构象变化可以模拟病毒-受体相互作用时发生的构象变化。在这里，我们采用小角中子散射与对比度的变化，以探测如何的结构的一个生长的辛德毕斯病毒响应于中等酸性的pH值。发生了几个变化时，整个病毒体结构的pH值从7.2下降到6.4。具体而言，病毒体核心中的RNA经历构象变化。此外，蛋白质被重新分配。大量的蛋白质从含有脂质双层的层移动到病毒体的外部。这些结果提高了我们对辛德毕斯病毒结构pH驱动改变的理解。
Alphaviruses, such as Sindbis virus, undergo dramatic changes in three-dimensional structure upon exposure to low pH, and such exposure can establish conditions allowing fusion of the virus membrane with a cell plasma membrane upon return to neutral pH. While exposure to low pH is not required for entry of Sindbis virus into vertebrate or invertebrate cells, the conformational changes occurring at low pH may mimic those occurring upon virus-receptor interaction. Here, we employed small-angle neutron scattering with contrast variation to probe how the structure of a mammalian-grown Sindbis virus responds to moderately acidic pH. Several changes took place throughout the virion structure when the pH decreased from 7.2 to 6.4. Specifically, the RNA in the virion core underwent a conformational change. Additionally, the protein was redistributed. A significant amount of protein moved from the layer containing the lipid bilayer to the exterior of the virion. The results improve our understanding of the pH-driven alteration of Sindbis virus structure.