通过一种胺-1-酸盐转移蛋白进行非膀性贩运,调节了eicosanoids
Dhirendra K Simanshu1, Ravi Kanth Kamlekar, Dayanjan S Wijesinghe
1Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10065, USA.
Nature
|July 19, 2013
概括
一种新发现的脂质转移蛋白,CPTP,特别是在膜之间移动胺-1-酸盐 (C1P). 这种蛋白质的蛋白质.
科学领域:
- 脂质信号传递和膜贩运.
- 蛋白质的结构和功能.
- 炎症和疾病的发病因子
背景情况:
- 化脂像胺-1-酸盐 (C1P) 调节关键的细胞过程,包括炎症.
- C1P激活脂酶A2α (cPLA2α),启动对喘和癌症等疾病相关的促炎性eicosanoid生产.
- 对于控制炎症,有效的C1P传输和呈现的细胞机制至关重要,但对非膀传输途径的了解仍然很少.
研究的目的:
- 为了识别和表征参与胺-1-酸盐 (C1P) 非膀转移的新型蛋白质.
- 阐明C1P识别和由脂质转移蛋白结合的分子机制和结构基础.
- 研究已识别的C1P转移蛋白在调节C1P恒温和下游信号传导中的细胞局部化和功能作用.
主要方法:
- 生物化学测试以评估脂质转移活性.
- 进行X射线晶体学以确定与C1P结合的已识别蛋白质的结构.
- 使用显微镜进行细胞局部化研究.
- RNA干扰 (RNAi) 来耗尽蛋白质并观察细胞表型.
主要成果:
- 一种无处不在表达的脂质转移蛋白,人类GLTPD1 (重新命名为CPTP),被确定为一种特定的C1P转移蛋白.
- 晶体结构揭示了一种新的结合机制,涉及酸盐头组识别部位和适应性疏水口袋,用于脂质链结合.
- CPTP局部化到细胞质中,并与跨戈尔吉网络,核和血膜相关联.
- 由于CPTP耗尽,导致C1P分布发生变化,cPLA2α活性增加,并增强了促炎性eicosanoid生成.
结论:
- CPTP是一种新的,结构独特的脂质转移蛋白,它专门在膜之间结合和转移C1P.
- CPTP在调节C1P细胞局部化方面发挥着关键作用,从而影响cPLA2α激活和炎症性eicosanoid生产.
- 了解CPTP的机制为由异常C1P信号驱动的炎症性疾病提供了潜在的治疗点.
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