需要通过NAGK对muramyl的酸化来激活NOD2
Che A Stafford1, Alicia-Marie Gassauer1, Carina C de Oliveira Mann1
1Gene Center and Department of Biochemistry, Ludwig-Maximilians-Universität, Munich, Germany.
Nature
|August 24, 2022
概括
N-乙糖胺激酶 (NAGK) 对于检测细菌甘氨酸成分,如muramyl二 (MDP) 是必不可少的. NAGK可化MDP,使先天免疫受体NOD2能够感知细菌细胞壁并触发免疫反应.
科学领域:
- 天生的免疫力
- 分子生物学
- 微生物学
背景情况:
- 细菌细胞壁含有糖素 (PGN),这是一个由天生的免疫受体识别的结构.
- 穆拉二 (MDP) 是PGN的关键免疫成分,由NOD2感知.
- NOD2的激活对肠道屏障功能和炎症反应至关重要.
研究的目的:
- 通过先天免疫系统检测MDP的新因素.
- 阐明NOD2感知MDP的机制.
- 了解氨基糖代谢与细菌细胞壁免疫之间的联系.
主要方法:
- 转发基因查以确定MDP检测所必需的基因.
- 生物化学测试以确定已确定的因子的酶活性.
- 在淘汰/缺陷细胞和动物模型中分析免疫反应.
主要成果:
- 确定N- 乙糖胺激酶 (NAGK) 对于MDP免疫刺激活性至关重要.
- NAGK直接化MDP以产生6-O--MDP.
- 6-O--MDP,但不是未修改的MDP,作为NOD2的激动剂.
- 缺乏NAGK的巨细胞无法感知MDP.
结论:
- NAGK是NOD2信号的关键上游调节器.
- NAGK将氨基糖代谢与细菌糖的先天免疫识别联系在一起.
- 这一发现为对抗细菌感染的宿主防御提供了新的洞察力.
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