在炎症酶激活和HMGB1释放中PKR的新型作用
Ben Lu1, Takahisa Nakamura, Karen Inouye
1Laboratory of Biomedical Science, The Feinstein Institute for Medical Research, 350 Community Drive, Manhasset, New York 11030, USA. blu@nshs.edu
Nature
|July 18, 2012
概括
双链RNA依赖蛋白激酶 (PKR) 对于炎症酶激活至关重要. 抑制PKR可能通过阻断细胞因子释放来治疗炎症性疾病.
科学领域:
- 免疫学 免疫学 免疫学
- 分子生物学分子生物学
- 细胞信号传输 细胞信号传输
背景情况:
- 炎症组复合体协调关键炎症性细胞因子的释放,包括IL-1β,IL-18和HMGB1.
- 了解调节炎酶激活的机制对于开发有针对性的抗炎疗法至关重要.
研究的目的:
- 研究双链RNA依赖蛋白激酶 (PKR,也称为EIF2AK2) 在炎症酶激活中的作用.
- 阐明PKR影响炎症体信号传递的分子机制.
主要方法:
- 用各种炎症酶激动剂刺激巨细胞.
- 基因删除和PKR的药理抑制.
- 对细胞因子释放的评估 (IL-1β,IL-18,HMGB1).
- 同免疫沉试验用于研究蛋白质相互作用.
- 在实验室中使用重组蛋白质复制炎症酶活性.
主要成果:
- 在暴露于炎症酶激动剂时诱导PKR自化.
- PKR 缺乏或抑制显著损害了各种刺激的炎症酶激活,包括细菌和病毒成分,ATP 和晶体物质.
- 在物理上,PKR与多个炎症组分 (NLRP3,NLRP1,NLRC4,AIM2) 相互作用.
- 在无细胞系统中,使用PKR,NLRP3,ASC和pro-caspase-1实现了炎症酶活性的重建.
结论:
- 在调节炎酶激活方面,PKR发挥着关键和广泛的作用.
- PKR代表了管理炎症状况的潜在治疗标.
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