C端截断的葡萄糖输送器被锁定在面向内部的形式中,没有运输活动
1Third Department of Internal Medicine, Faculty of Medicine, University of Tokyo, Japan.
Nature
|June 7, 1990
概括
通过删除其C端域来改变GLUT1葡萄糖载体,使其变得不活跃. 这表明C端域对传送器的结构变化和功能至关重要.
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:
- 促进葡萄糖运输体,如GLUT1,是具有12个膜跨域的蛋白质家族.
- 一种交替形状模型解释了促进葡萄糖运输的机制.
- 细胞内C端 (C端) 域在GLUT1功能中的作用尚未完全理解.
研究的目的:
- 为了研究GLUT1传送器的结构功能关系.
- 确定细胞内C端域在GLUT1介导的葡萄糖运输中的特定作用.
主要方法:
- 一种子GLUT1传送器的删除突变被使用补充DNA (cDNA) 设计.
- 突变者缺乏来自细胞内C终端域的42种氨基酸中的37种.
- 突变的载体表达在中国仓鼠卵巢 (CHO) 细胞中.
主要成果:
- 在CHO细胞的细胞表面成功表达了GLUT1删除突变.
- 修改后的GLUT1输送器没有表现出葡萄糖输送活动,这表明功能失活.
- 假设功能的丧失是由于无法交替变形而导致的.
结论:
- GLUT1的细胞内C端域对其运输功能至关重要.
- 删除C端域可能会阻止葡萄糖运输所需的形状变化.
- GLUT1的C端域在维持载体在向内和向外的形状之间切换的能力方面发挥着至关重要的作用.
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