互动组地图揭示了通过氧结合蛋白来运输酸
Kenji Maeda1, Kanchan Anand, Antonella Chiapparino
1European Molecular Biology Laboratory, EMBL, Meyerhofstrasse 1, D-69117 Heidelberg, Germany.
Nature
|August 13, 2013
概括
研究人员发现,特定的脂质转移蛋白 (LTPs),Osh6和Osh7,从内分泌网膜向酵母中的血膜非血管运输脂胺素 (PS). 这揭示了PS恒温和OSBP功能的新机制.
科学领域:
- 细胞生物学 细胞生物学
- 生物化学 生物化学
- 分子生物学分子生物学
背景情况:
- 细胞需要调节的脂质运输来进行器官专业化.
- 脂素 (PS) 在内分泌网膜中合成,并通过未知的机制移动到血膜.
- 脂质转移蛋白 (LTP) 促进非膀性脂质运动.
研究的目的:
- 开发一种综合方法,结合蛋白质分离和脂质组学,以在体内表征LTP-脂质复合体.
- 为了研究Sec14同质 (Sfh) 和氧结合同质 (Osh) 蛋白在Saccharomyces cerevisiae中的脂质运输中的功能.
主要方法:
- 开发了一种使用蛋白质分成和脂管学的综合方法.
- 将该方法应用于酵母中的13个LTP (6个Sfh和7个Osh蛋白).
- 确定了与PS结合的Osh6的结构.
主要成果:
- 奥什6和奥什7对酸丁素 (PS) 具有意想不到的特异性.
- 这些蛋白质参与PS恒温和传输到活体中的血膜.
- Osh6-PS的结构显示了metazoan氧化醇结合蛋白 (OSBPs) 中的保存特征,这对PS识别至关重要.
结论:
- 提供了第一个非膀性PS从ER转移到血膜的直接证据.
- 确定了一种新的OSBP亚家族 (包括人类ORP5和ORP10),可以转移PS.
- 为OSBP在脂质运输和人类疾病中的功能提出了新的机制.
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