用净化的成分复制管状内等质网
Robert E Powers1,2, Songyu Wang1,2, Tina Y Liu1,2
1Howard Hughes Medical Institute, Harvard Medical School, 240 Longwood Avenue, Boston, Massachusetts 02115, USA.
Nature
|February 23, 2017
概括
细胞有机体的形状,就像内细胞网一样,是由一小组蛋白质维持的. 这种动态的管状网络需要连续的膜融合和依赖能源的稳定状态过程.
科学领域:
- 细胞生物学
- 分子生物学
- 生物物理
背景情况:
- 器官形态对于细胞功能至关重要,但器官形状的机制在很大程度上是未知的.
- 细胞内膜网 (ER) 具有复杂,动态的管状网络,其形成尚未完全理解.
- 几种膜蛋白与ER网络形成有关,但它们的确切作用和必要性尚不清楚.
研究的目的:
- 调查内质网管网络形成和维持的分子机制.
- 确定特定的膜蛋白,如Sey1p和Yop1p在形成ER结构中的作用.
- 使用纯化的蛋白质来复制和分析ER网络形成.
主要方法:
- 在蛋白质体中使用纯化的内膜蛋白质 (Sey1p和Yop1p) 构建动态管状膜网络.
- 使用GTP添加来启动网络形成,并抑制GTP水解来研究网络维护.
- 测试Sey1p与其他曲率稳定蛋白 (网膜,REEPs) 以及其脊椎动物对应蛋白Atlastin的相互作用.
主要成果:
- 含有Sey1p (膜融合GTPase) 和Yop1p (曲率稳定蛋白) 的蛋白质在添加GTP时形成一个管状网络.
- 抑制Sey1p的GTP水解导致了管的快速碎片化,这表明需要持续的膜融合.
- Sey1p成功地与各种曲率稳定蛋白形成了网络,而Atlastin则独立地形成了依赖GTP水解的网络.
结论:
- 有机体形状,特别是ER管状网络,可以由最小的蛋白质组生成.
- 网络维护是一个能源依赖的过程,它代表了膜融合和拆卸之间的稳定状态.
- Sey1p和Atlastin是ER网络结构和动态的关键调节者.
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