一组链球菌诱导质细胞中的GSDMA依赖性质死
Doris L LaRock1, Anders F Johnson1, Shyra Wilde1
1Department of Microbiology and Immunology, Emory School of Medicine, Atlanta, GA, USA.
Nature
|May 11, 2022
概括
一组链球菌蛋白酶SpeB触发了GSDMA依赖的细胞灭绝,这是皮肤免疫的关键途径. 这一发现表明GSDMA是细菌毒性因子的直接传感器.
科学领域:
- 细胞生物学
- 免疫学
- 微生物学
背景情况:
- 气体皮质蛋白 (GSDM) 是形成孔隙的蛋白质,它调解细胞灭绝,即被编程的细胞死亡.
- GSDM的激活通常涉及酶介导的抑制域的分裂.
- 一个关键的GSDM家族成员GSDMA的激活剂仍然未知.
研究的目的:
- 为了确定GSDMA的激活剂.
- 调查GSDMA在对A组链球菌 (GAS) 的宿主防御中的作用.
- 探索GSDM作为微生物毒性因素的直接传感器.
主要方法:
- 生物化学测定检测GSDMA的SpeB裂变
- 基于细胞的测定,使用角质细胞和GAS菌株.
- 使用GSDMA绝杀小鼠模型的体内研究.
主要成果:
- 一组链球菌分泌的蛋白酶SpeB分裂并激活GSDMA.
- 由 SpeB 诱导的 GSDMA 激活会导致皮肤角质细胞的灭.
- 在小鼠中,GSDMA 缺乏增加了侵入性 GAS 感染的易感性.
结论:
- GSDMA对抗侵袭性GAS皮肤感染的免疫防御至关重要.
- GSDMA作为外源细菌蛋白酶的直接传感器,如SpeB.
- 这突显出一种新的机制, GSDM 绕过宿主调节器来检测微生物威胁.
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