结合LPS的酶激活和招募域 (CARDs) 是两部分的脂质结合模块
Anh B Cao1, Pascal Devant1, Chengliang Wang2
1Division of Gastroenterology, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA.
bioRxiv : the preprint server for biology
|October 17, 2024
概括
卡斯帕-11的脂质结合域通过不同的区域识别了自身和外来脂质. 这种保存的机制允许从一个祖先的鱼蛋白中设计出一种新的脂多糖 (LPS) 结合域.
科学领域:
- 免疫学 免疫学 免疫学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 卡斯巴-11作为一种模式识别受体 (PRR) 检测细胞质细菌脂聚糖 (LPS).
- 它可以识别非自我 (细菌LPS) 和自我脂质,这引发了关于共享识别机制的问题.
- 卡斯巴-11触发热,一种炎症性细胞死亡形式.
研究的目的:
- 调查 caspase-11 的 caspase 激活和招募域 (CARD) 与自我和非自我脂质相互作用的分子机制.
- 为了确定CARD内部的共同或不同的区域是否负责结合不同类型的脂质.
- 探索基于保存结构特征的新型脂质结合域的工程潜力.
主要方法:
- 生物化学试验分析脂蛋白相互作用.
- 计算建模以了解绑定接口.
- 基于细胞的测试,以评估脂质结合的功能后果.
- 使用祖先域的蛋白质工程方法.
主要成果:
- 卡斯巴酶-11 CARD 作为双部分脂质结合模块,具有与酸盐组和酸盐链相互作用的不同区域.
- 自体和非自体脂质都与CARD中的特定部位结合.
- 自脂结合在caspase-11同类物和正基物中是进化保守的.
- 一个LPS绑定域成功地从一个祖先的鱼类CARD类域中 *de novo* 进行了工程设计.
结论:
- 这些发现揭示了caspase-11对脂质识别的保守分子基础,其中涉及一个双分结合模块.
- 这项研究强调了先天免疫中自我和非自我脂质歧视之间的复杂关系.
- 一个新的LPS结合域的工程证明了基于进化见解操纵PRR功能的潜力.
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