通过冷-EM揭示了baculovirus核体的结构
Xudong Jia1, Yuanzhu Gao1,2, Yuxuan Huang1
1State key laboratory of biocontrol, School of Life Sciences, Sun Yat-sen University, 510275, Guangzhou, China.
Nature communications
|November 18, 2023
概括
使用冷EM确定了Autographa californica多重核多重体病毒 (AcMNPV) 核体的结构. 这揭示了VP39和其他蛋白质的排列,有助于理解baculovirus组装和功能.
科学领域:
- 结构生物学是结构生物学.
- 病毒学 病毒学
- 生物化学 生物化学
背景情况:
- 像AcMNPV这样的百科病毒是重要的生物杀虫剂和蛋白质表达系统.
- 关于baculovirus蛋白质结构的知识是有限的,这阻碍了对其功能的充分理解.
- 该AcMNPV核体是一个复杂的组合,由许多蛋白质子单元组成.
研究的目的:
- 为了阐明AcMNPV核体的高分辨率结构.
- 描述蛋白质成分及其在核囊中的排列.
- 提供关于baculovirus组装,稳定性和潜在应用的见解.
主要方法:
- 使用冷电子显微镜 (cryo-EM) 来确定结构.
- 核体,头部和底部的高分辨率结构分析.
- 计算建模,包括AlphaFold2,用于结构改进.
主要成果:
- 确定了AcMNPV核体VP39螺旋体的3.2 Å分辨率结构.
- 头部和底部的4.3 Å分辨率结构显示了100多个蛋白质子单元.
- VP39表现出类似HK97的折叠特征,并使用二硫化物键进行组装.
- 特定的蛋白质 (AC104,AC142,AC109,AC101,AC144) 在核囊末端形成不同的层和结构.
结论:
- 这项研究为AcMNPV核囊体提供了前所未有的结构细节.
- 这些发现澄清了VP39和其他蛋白质在核囊形成和稳定性中的作用.
- 拟议的AlphaFold2应用程序为在中间分辨率下建模结构提供了一种新方法.
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