通过eIF2α-P的持续转化抑制调解子神经退行
Julie A Moreno1, Helois Radford, Diego Peretti
1MRC Toxicology Unit, Hodgkin Building, University of Leicester, Lancaster Road, Leicester LE1 9HN, UK.
Nature
|May 25, 2012
概括
持续的蛋白质错折导致神经元死亡,因为它关闭了蛋白质合成. 恢复蛋白质翻译速率,防止神经退行,并改善小鼠的生存率.
科学领域:
- 神经科学是一个神经科学.
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
背景情况:
- 神经退行性疾病,如阿尔茨海默病,帕金森病和子疾病,涉及错误折叠的蛋白质积累.
- 展开的蛋白质反应 (UPR) 是对错误折叠的蛋白质的细胞防御,包括通过eIF2α-P关闭蛋白质翻译.
- UPR激活,eIF2α-P和神经退行症之间的联系仍然不清楚.
研究的目的:
- 研究蛋白积累和eIF2α-P在诱导的神经退行症中的作用.
- 为了确定恢复蛋白质翻译是否可以在病模型中具有神经保护作用.
- 探索针对神经退行性疾病的转化控制的治疗策略.
主要方法:
- 利用子疾病的小鼠模型研究子蛋白积累及其对蛋白质合成的影响.
- 研究了eIF2α-P水平对突触功能和神经元损失的影响.
- 采用遗传 (GADD34过度表达,RNA干扰) 和药理学 (salubrinal) 方法来调节eIF2α-P和蛋白质翻译.
主要成果:
- 蛋白积累导致通过eIF2α-P持续的翻译抑制,在小鼠中导致突触失败和神经元损失.
- 过度表达GADD34或降低蛋白水平降低了eIF2α-P,恢复了蛋白质翻译,并挽救了突触缺陷和神经元损失,增加了生存率.
- 抑制eIF2α-P脱化,导致盐内毒性恶化神经毒性和降低存活率.
结论:
- 由eIF2α-P介导的持续的翻译抑制是病中神经退行的一个关键机制.
- 恢复蛋白质翻译速率提供了一个神经保护策略.
- 针对转化控制等常见途径,而不是疾病特异性机制,有望治疗各种神经退行性疾病.
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