来自内细胞网膜的压力信号的伴侣抑制的结构基础
Lisa Neidhardt1, Joanne Tung1, Miriam Kuchersky2
1Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, UK.
Molecular cell
|October 24, 2025
概括
细胞内膜网膜的辅导体AGR2通过结合和破坏IRE1β二次体来抑制未折叠蛋白反应 (UPR). 这种机制确保了UPR在需要时被启动.
科学领域:
- 细胞生物学 细胞生物学
- 蛋白质折叠的分子机制
- 细胞内膜网膜的应激反应应激反应
背景情况:
- 细胞内膜网膜 (ER) 展开的蛋白质反应 (UPR) 调节细胞的压力.
- 众所周知,像AGR2这样的储备伴侣会抑制UPR传感器,但机制尚不清楚.
- AGR2 特别抑制了 UPR 传感器 IRE1β.
研究的目的:
- 阐明AGR2抑制IRE1β的结构机制.
- 了解AGR2结合如何破坏IRE1β功能.
- 调查AGR2在调整UPR中的作用.
主要方法:
- 结构预测和X射线晶体学以确定AGR2-IRE1β相互作用.
- 用NMR光谱分析分子相互作用.
- 低温电子显微镜 (cryo-EM) 用于高分辨率的结构重建.
- 分子动力学模拟以建模动态结合事件.
主要成果:
- 确定了AGR2单体和IRE1β的调节循环之间的关键相互作用.
- 确定一个AGR2二元体,而不是单元体,在抑制复合体中结合IRE1β.
- 化EM揭示了一种不对称的结合模式,其中一个AGR2原体结合了调节循环,第二个破坏了IRE1β二分化.
- 分子动力学模拟显示,第二个AGR2原利用了短暂的IRE1β二元体波动.
结论:
- AGR2通过结构性地破坏 IRE1β 二次体来抑制 UPR,防止其激活.
- 这种干扰机制涉及AGR2二元体与IRE1β的特定不对称结合.
- 该系统是通过与IRE1β竞争的陪伴客户端进行UPR激活的,这些客户端与IRE1β竞争AGR2结合.
关键词:
细胞内膜网膜的内oplasmic网膜.肠道粘膜是指肠道的粘膜.分子的陪伴者是分子的陪伴者.蛋白质的多元化.信号传导的信号传导.跨膜蛋白质是一种跨膜蛋白质.不传统的拼接方式.不折叠的蛋白质反应反应更多相关视频
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