德洛索菲拉白分离蛋白是一种负端定向的运动分子
R A Walker1, E D Salmon, S A Endow
1Department of Biology, University of North Carolina, Chapel Hill 27599.
Nature
|October 25, 1990
概括
德洛索菲拉菌中的白蛋白,对于染色体分离至关重要,表现出新的运动活性. 这种蛋白质类似于氨酸,向微管的负端移动,这表明氨酸和氨酸电机之间的祖先联系.
科学领域:
- 细胞生物学 细胞生物学
- 分子电机分子电机
- 遗传学 是一个遗传学.
背景情况:
- 在Drosophila中,克拉雷特产物对于在雌性半转化和早期胚胎转化过程中准确分离染色体至关重要.
- 最近的发现表明,白分离蛋白和多索菲拉基因素重链之间存在显著的氨基酸序列相似性.
研究的目的:
- 为了表征细菌表达的白兰地分离蛋白的体外运动活性.
- 为了研究克拉莱特和基因素之间的序列相似性的功能意义.
主要方法:
- 细菌表达的白兰地分离蛋白.
- 试管体内运动性测定用于分析运动活动,包括速度,方向性,扭矩生成和抑制器灵敏度.
主要成果:
- 细菌表达的白蛋白显示出具有独特特征的运动活性.
- 它表现出缓慢的运动 (4微米/分钟),与基因素或基因素不同.
- 电机表现出负端定向运动,扭矩产生,以及对特定抑制剂的敏感性,类似于dyneins.
- 这一发现表明dynein和kinesin运动域之间存在祖先关系.
结论:
- 克拉雷特电机的减值终端导向活动支持其在染色体运动中的作用沿着螺旋微管在前兆期和/或异位期.
- 这项研究提供了基因素和基因素运动蛋白之间的祖先联系的证据.
- 克拉瑞特蛋白代表了一种新型分子电机类,对理解染色体分离机制有意义.
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