与素相关的运动器ncd的运动域的晶体结构
E P Sablin1, F J Kull, R Cooke
1Department of Biochemistry/Biophysics, University of California, San Francisco, California 94143, USA.
Nature
|April 11, 1996
概括
素电机沿着微管子移动. 对ncd和kinesin运动域的结构比较揭示了保存的特征,表明共享的微管结合点和方向运动的共同机制.
科学领域:
- 分子生物学分子生物学
- 细胞动态 细胞动态
- 结构生物学是结构生物学.
背景情况:
- 基于微管的ATPases,如素超级家族的电机,对于细胞功能至关重要.
- 氨酸和ncd (一种与氨酸相关的运动器) 沿着微管表现出相反的方向运动,尽管它们的运动领域具有显著的序列相同性.
研究的目的:
- 为了确定Drosophila ncd运动域的晶体结构.
- 为了比较ncd和kinesin运动领域的结构.
- 提出一种模型,用于kinesin和ncd运动的相反极性.
主要方法:
- 进行X射线晶体学以确定Drosophila ncd运动域的MgADP复合物的2.5A晶体结构.
- 与已知的动态结构进行结构比较.
- 与其他NTPase (肌肉蛋白,G蛋白) 的功能和结构比较.
主要成果:
- 这两个运动领域具有显著的结构相似性.
- 保存的表面氨基酸位置表明NCD和kinesin有一个共同的微管结合点.
- 结构和功能比较表明,在各种NTP阶段中,NTP和NDP状态之间的构造变化存在保存机制.
结论:
- 提出了一个通用模型,用于将一个常见的马感应机制转换为对立的极性运动,用于kinesin和ncd.
- 这些发现提供了关于kinesin超级电机家族中定向运动性的分子基础的见解.
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