感应受体通过Ca2+和cAMP调节NLRP3炎症体
Geun-Shik Lee1, Naeha Subramanian, Andrew I Kim
1Inflammatory Disease Section, Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland 20892, USA.
Nature
|November 13, 2012
概括
感应受体 (CASR) 通过 (Ca2+) 和循环AMP (cAMP) 信号激活NLRP3炎症体. CASR功能障碍有助于导致CAPS等自身炎症性疾病.
科学领域:
- 免疫学 免疫学 免疫学
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- 低氨酸相关周期性综合征 (CAPS) 是一种由NLRP3基因突变引起的自身炎症性疾病.
- NLRP3炎症酶激活对中白素-1β (IL-1β) 成熟至关重要,但其精确的机制尚不清楚.
- 现有的NLRP3激活模型包括K+流量,活性氧物种和溶酶体不稳定.
研究的目的:
- 阐明NLRP3炎症酶激活的分子机制.
- 了解CAPS相关突变如何激活NLRP3.
- 为了确定NLRP3炎症酶激活的关键分子调节者.
主要方法:
- 使用小鼠模型研究了感受受体 (CASR) 在NLRP3炎症酶激活中的作用.
- 利用CASR的淘汰来评估其对炎症酶激活的必要性.
- 研究了细胞内Ca2+和循环AMP (cAMP) 水平对NLRP3炎症酶组合和活性的影响.
- 评估了cAMP与野生类型和突变NLRP3.3的结合亲和力.
主要成果:
- 通过增加细胞内Ca2+和降低cAMP,CASR激活导致NLRP3炎症酶激活.
- CASR激动剂可以独立于外源ATP激活NLRP3炎症体.
- Knockdown 的 CASR 减少了已知的 NLRP3 激活器的炎症酶激活.
- 细胞质Ca2+的增加促进了炎症细胞组合,并且对于自发的CAPS相关的NLRP3活性是必需的.
- 降低cAMP水平独立地激活NLRP3炎症体,通过缓解其与NLRP3的抑制结合.
- 与CAPS相关的突变NLRP3表现出较低的cAMP结合亲和力,导致不受控制的IL-1β产生.
结论:
- Ca2+和cAMP是NLRP3炎症酶的关键分子调节者.
- 在NLRP3炎症酶激活过程中,CASR信号传递起着关键作用.
- 对Ca2+和cAMP信号的调节失调有助于CAPS的发病.
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