它的方向是由其茎的角度和长度控制的
Sinan Can1, Samuel Lacey2, Mert Gur3
1Physics Department, University of California at Berkeley, Berkeley, CA, USA.
Nature
|February 8, 2019
概括
研究人员设计了一种运动蛋白Dynein, 修改dinein的树干
科学领域:
- 分子生物学
- 细胞生物学
- 生物物理
背景情况:
- 细胞骨电机对于细胞内运输和细胞分裂至关重要.
- 大多数素和肌素电机都朝着丝片的一端移动,但有一些例外.
- 所有研究的dynein电机都只向微管子减去端移动.
研究的目的:
- 为了研究dynein运动定向的机制.
- 设计一种Saccharomyces cerevisiae dynein发动机,
- 了解氨酸的螺旋如何影响它沿着微管的运动.
主要方法:
- 低温电子显微镜
- 分子动力学模拟
- 单分子试验
- 糖菌的工程
主要成果:
- 卷轴的延长或缩短控制了微管周围的状方向性.
- 对茎的长度和角度的修改成功地将dinein的移动性逆转为正极.
- 变化的茎几何改变了与微管相对的dynein连接器的摆动方向.
结论:
- 它的结构决定了它的负极方向性.
- 保存的茎结构解释了为什么所有已知的dyneins都向微管减去端移动.
- 的修改为运动蛋白质机制和进化提供了洞察力.
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