DDI2的损失通过CCN1驱动的补偿性自细胞转换蛋白质稳定
Nayyerehalsadat Hosseini1,2,3, Ahmed M Elshazly1,4,5, Holly A Byers1,2
1Department of Pathology, Virginia Commonwealth University, Richmond, VA, USA.
iScience
|March 11, 2026
概括
丢失DDI2蛋白质降解穿会导致有毒的CCN1积累,引发细胞应激和自. 这揭示了ubiquitin-proteasome系统和自-溶酶体通路之间的新联系,提供了治疗点.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 无素蛋白酶体系统 (UPS) 和自酶体通路 (ALP) 对蛋白质降解至关重要.
- UPS和ALP之间的分子联系在很大程度上是未知的.
- 了解这些连接对于细胞蛋白质稳定至关重要.
研究的目的:
- 研究连接UPS和ALP的分子机制.
- 阐明DDI2在蛋白质降解和细胞应激反应中的作用.
- 在蛋白酶组依赖性癌症中识别潜在的治疗点.
主要方法:
- 利用多样化的人类和小鼠细胞系.
- 研究了DDI2损失对蛋白质积累和细胞压力的影响.
- 检查了CCN1局部化及其与细胞降解途径的相互作用.
- 评估了活性氧物种 (ROS) 和补偿性自的作用.
主要成果:
- DDI2的损失导致分泌蛋白CCN1的细胞内积累,导致蛋白质毒性压力.
- DDI2 通过 DDI2-p97 复合物从 ER 中提取错误折叠的 CCN1,以促进 lysosomal 降解.
- CCN1积累诱导ROS的产生并触发补偿性自,由CCN1淘汰或ROS清理减弱.
- DDI2的缺陷会影响CCN1-LAMP1的同位分,这表明DDI2的作用是选择性货物受体.
结论:
- 通过调解CCN1降解,DDI2充当了UPS和ALP之间的关键环节.
- 一个应激响应的DDI2-CCN1轴调节蛋白质稳定.
- 在依赖蛋白质组的癌症中,DDI2代表了潜在的治疗脆弱性.
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