ADAR1p150通过不同的机制阻止MDA5和PKR激活,以避免致命的自身炎症
Shi-Bin Hu1, Jacki Heraud-Farlow2, Tao Sun1
1Department of Genetics, Stanford University, Stanford, CA 94305, USA.
Molecular cell
|October 5, 2023
概括
编辑RNA的酶ADAR1可以防止免疫系统过度激活. 它的损失通过激活MDA5和PKR传感器引发致命的炎症,突出显示它们在天生的免疫力中的关键作用.
科学领域:
- 天生的免疫力和核酸感应.
- 编辑RNA和免疫调节.
背景情况:
- 有效的免疫依赖于区分自我与非自我核酸.
- 细胞双链RNAs (dsRNAs) 被ADAR1编辑,以防止被MDA5和PKR等细胞质传感器识别.
- 失去ADAR1-介导的RNA编辑激活MDA5,但其他ADAR1功能仍然不清楚.
研究的目的:
- 阐明在ADAR1丢失时导致自身炎症的特定机制和体内因子.
- 在没有ADAR1-介导的RNA编辑的情况下,确定MDA5和PKR的作用.
主要方法:
- 研究了ADAR1损失及其RNA编辑独立功能的背景下MDA5和PKR的激活.
- 使用MDA5和PKR中缺失的Adar1p150-/-小鼠模型来评估救援表型.
- 分析了ADAR1的dsRNA结合活性对PKR激活的影响.
主要成果:
- 失去ADAR1介导的RNA编辑特异地激活了MDA5.5.
- 细胞质ADAR1p150异型或其dRNA结合活性的损失会激活PKR.
- 同时删除MDA5和PKR完全挽救了Adar1p150-/-小鼠的胚胎死亡率.
结论:
- 当ADAR1p150丢失时,MDA5和PKR是主要的体内效应因子,导致致命的自身炎症.
- 这项研究澄清了ADAR1的RNA编辑和非编辑功能的在免疫恒温中的不同作用.
- 了解这些途径对于开发自身炎症性疾病治疗方法至关重要.
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