核酸依赖的构造变化直接出口由携带器与抗原处理相关的输出器.
James Lee1, Victor Manon1,2, Jue Chen1,3,4
1Laboratory of Membrane Biophysics and Biology, The Rockefeller University, New York, NY 10065.
bioRxiv : the preprint server for biology
|July 16, 2025
概括
与抗原处理 (TAP) 相关的载体将移动到内细胞网膜中,以获得适应性免疫. 低温EM结构揭示了其运输周期,显示了它如何结合,运输和释放.
科学领域:
- 结构生物学 结构生物学
- 免疫学 免疫学 免疫学
- 分子生物学分子生物学
背景情况:
- 与抗原处理相关的载体 (TAP) 通过将转运到内分泌网膜以进行MHC-I加载,对适应性免疫至关重要.
- 虽然TAP的结选择性是已知的,但其运输和释放机制仍然不清楚.
研究的目的:
- 为了阐明人体TAP的化物运输的结构机制.
- 想象TAP在整个运输周期中的多个功能状态.
主要方法:
- 使用冷电子显微镜 (cryo-EM) 来确定人类TAP的高分辨率结构.
- 结构被捕获在各种功能状态,包括向内面和向外面的形状.
主要成果:
- ATP结合稳定了TAP的向内变形.
- 一个取决于温度的向外转向状态的过渡重新配置了结位以释放.
- 通过ATP水解和核酸结合域 (NBD) 分离,重新设置了运输循环.
结论:
- 这些结构为了解TAP的化物运输机制提供了全面的框架.
- 这些发现提供了对瓦纳达特捕获和跨抑制机制的见解.
- 这项工作阐明了TAP如何促进酸载入MHC-I分子.
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