在Ty1病毒类粒子组合过程中,体的灵活性.
Bryan S Sibert1,2,3, J Adam Hannon-Hatfield4, Giuseppe Nicastro5
1Department of Biochemistry, University of Wisconsin, Madison, WI, 53706, United States.
bioRxiv : the preprint server for biology
|December 25, 2025
概括
Ty1逆转移子形成具有多样结构的病毒样粒子 (VLPs),而不是真正的二面体形状. 这种异质性源于灵活的Gag蛋白组合,揭示了对LTR逆转移子组织的新见解.
科学领域:
- 结构生物学是结构生物学.
- 分子生物学分子生物学
- 病毒学 病毒学
背景情况:
- Ty1/Copia家族 (Pseudoviridae) 包含在真核生物中发现的LTR逆转移体,与逆转录病毒共享祖先.
- Ty1逆转移子组装成类似病毒的粒子 (VLPs),主要由Gag和Gag-Pol蛋白组成.
研究的目的:
- 为了确定Ty1 VLP中的结构组织和Gag蛋白相互作用.
- 阐明 Ty1 VLP 的异质形态背后的机制.
主要方法:
- 纯化的Ty1 VLP的冷电子断层扫描 (冷ET).
- 亚断层图像平均值 (STA) 用于生成高分辨率的EM密度图.
- 为了建模蛋白质域 (CA-CTD和CA-NTD),使用X射线晶体学和溶液NMR.
主要成果:
- 在Ty1 VLP中确定了独特的五角形和六角形体结构.
- 证明Ty1 VLPs表现出多样化的体安排,不同于二元体型病毒.
- 模拟了Ty1 Gag囊的C端域 (CA-CTD) 和N端域 (CA-NTD),揭示了组装至关重要的界面-2的灵活性.
- 连接了体灵活性与异质的VLP大小和形态.
结论:
- 由于灵活的Gag蛋白组合,Ty1 VLPs具有非二体,异质的结构.
- Ty1 Gag 蛋白质的结构可塑性允许不同的体安排,解释了 VLP 的异质性.
- 这些发现提供了对LTR逆转移素组装和演变的更深入的理解.
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