阻止RIPK1的酶分裂的突变导致自身炎症性疾病
Najoua Lalaoui1,2, Steven E Boyden3, Hirotsugu Oda4
1The Walter and Eliza Hall Institute, Parkville, Victoria, Australia. lalaoui@wehi.edu.au.
Nature
|December 13, 2019
概括
对胚胎发育和预防自身炎症综合征至关重要. 阻止这种分裂的突变会导致人类的严重炎症疾病和小鼠的胚胎死亡.
科学领域:
- 免疫学
- 分子生物学
- 遗传学
背景情况:
- 受体相互作用蛋白激酶1 (RIPK1) 调节先天的免疫信号.
- RIPK1在翻译后受到修改,包括通过caspase-8裂变,但其作用尚不清楚.
- 据认为,Caspase-8裂变可以抑制RIPK3的激活和亡.
研究的目的:
- 研究酶介导的RIPK1裂变的生理相关性.
- 定义由抗分裂RIPK1引起的自身炎症综合征的机制.
- 确定RIPK1裂变在胚胎发育和炎症平衡中的作用.
主要方法:
- 产生了人类细胞系和具有阻止RIPK1酶分裂 (Ripk1D325A) 突变的小鼠模型.
- 分析了突变小鼠的胚胎死亡率,全身炎症和免疫细胞反应.
- 在突变小鼠的细胞中对TNF诱导的亡和亡的评估敏感性.
主要成果:
- 阻止RIPK1分裂的人类突变导致早期周期性发烧和淋巴腺病变.
- 抗裂变的Ripk1D325A/D325A小鼠表现出胚胎致死性,通过联合Casp8和Ripk3损失得到拯救.
- RIPK1激酶活动的丧失也会防止胚胎死亡,但会导致致命的炎症.
- Ripk1D325A/ D325A和Ripk1D325A/ +细胞对RIPK3依赖的亡和亡过敏.
- 异卵性Ripk1D325A/+小鼠对炎症刺激有过度反应.
结论:
- 通过酶介导的RIPK1裂变对胚胎发育至关重要.
- 抑制死亡和自身炎症综合征.
- 这种分裂对于维持整个生命的炎症平衡至关重要.
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