IRE1α激酶激活模式控制替代性内核酶输出,以确定分离的细胞命运
Dan Han1, Alana G Lerner, Lieselotte Vande Walle
1Department of Medicine, University of California, San Francisco, San Francisco, CA 94143-2520, USA.
Cell
|August 12, 2009
概括
展开的蛋白质响应 (UPR) 可以触发细胞死亡在细胞内网膜 (ER) 压力. 激酶抑制剂可以通过改变IRE1alpha RNase活性来阻止这种亡,从而促进细胞存活.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 生物化学 生物化学
背景情况:
- 细胞内膜网膜 (ER) 的压力激活了未折叠的蛋白质反应 (UPR),以恢复平衡.
- 如果无法实现平衡,UPR可以触发细胞亡,或编程细胞死亡.
- IRE1alpha,一种ER的跨膜激酶/内核酶 (RNase),在这个亡开关中起着至关重要的作用.
研究的目的:
- 调查IRE1alpha在ER压力期间调解亡中的作用.
- 探索调节IRE1alpha活性以促进细胞存活的机制.
主要方法:
- 利用化学遗传学研究IRE1alpha功能.
- 进行了体外溶解试验.
- 分析了mRNA拼接和衰变途径.
主要成果:
- ER压力诱导IRE1alpha自化,激活其RNase将XBP1mRNA拼接并降解其他ER局部化的mRNA.
- 激酶抑制剂绕过IRE1alpha自酸化,通过另一个模式激活RNase.
- 这种交替激活促进XBP1拼接,同时防止mRNA衰变,从而避免亡.
结论:
- IRE1alpha的双酶和RNase活动对于在ER压力期间确定细胞命运至关重要.
- 用激酶抑制剂调节IRE1alpha RNase活性可以将平衡转向细胞存活.
- 准IRE1alpha为涉及ER压力的疾病提供了潜在的治疗策略.
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