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脂质结合的寡糖体在ER膜上的转移需要Rft1蛋白质
Jonne Helenius1, Davis T W Ng, Cristina L Marolda
1Institute of Microbiology, Swiss Federal Institute of Technology, Zürich, CH-8092 Zürich, Switzerland.
Nature
|January 25, 2002
概括
研究人员确定了酵母中的RFT1蛋白质对于将关键的糖蛋白前体转移到内细胞网膜中至关重要. 这一发现揭示了真核细胞中保存的N-链糖化途径.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
背景情况:
- 与N结合的糖化是真核细胞中蛋白质修饰的关键,保存的途径.
- 该过程涉及组装一个四度二糖 (Glc3Man9GlcNAc2) 在内质网膜 (ER) 内的多利霍尔-酸盐载体上.
- lipid-linked oligosaccharide中间体在ER膜上的转移是必不可少的,但涉及的蛋白质 (flippases) 仍然难以捉摸.
研究的目的:
- 为了确定负责Man5GlcNAc2-PP-Dol中间体的跨膜运动的蛋白质.
- 为了研究这种蛋白质在N链 glycosylation 途径中的作用.
主要方法:
- 使用酵母作为模型生物体.
- 研究了RFT1基因及其编码蛋白的功能.
主要成果:
- 提供了酵母RFT1编码Man5GlcNAc2-PP-Dol转位所必需的蛋白质的证据.
- 证明RFT1是从细胞质中移动到ER膜的光侧的寡糖类中间体所需的.
- 表明RFT1是一种进化保存的蛋白质.
结论:
- RFT1是难以捉摸的翻转酶,催化了N结合甘氨基化中的基本转位步骤.
- 这一发现提升了我们对一种基本的细胞过程的理解,对各种细胞类型有影响.
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