动氨酸的GAP域的损伤刺激受体介导的内细胞分裂
S Sever1, A B Muhlberg, S L Schmid
1Department of Cell Biology, The Scripps Research Institute, La Jolla, California 92037, USA.
Nature
|April 17, 1999
概括
动氨酸蛋白的自我组装调节了细胞囊泡的形成. 这项研究显示,在受体介导的内细胞分裂中,动氨酸作为分子调节剂而不是力量发生器.
科学领域:
- 细胞生物学 细胞生物学
- 分子和结构生物学分子和结构生物学.
- 生物化学 生物化学
背景情况:
- 动氨酸是一种GTP水解蛋白,对克拉介导的内细胞分裂至关重要.
- 动氨酸在体外和体内自组装成项圈,刺激其GTPase活性.
- 以前有人提出,dynamin使用GTP水解来产生囊泡分裂的力.
研究的目的:
- 阐明动氨酸自我组装的机制及其在内细胞分裂中的作用.
- 为了研究激素的GTPase激活域的功能.
- 为了确定dynamin是否作为一种产生力GTPase或分子调节剂.
主要方法:
- 研究了胺自我组装和GTPase活性在体外和体内.
- 使用了具有自我组装刺激的GTPase活性缺陷的dynamin突变物.
- 观察到过度表达这些突变物对受体介导内细胞突变的影响.
主要成果:
- 动的自我组装是由一个特定的GTPase激活域协调的.
- 缺乏自我组装刺激的GTPase活性的动氨酸突变的过度表达加速了内细胞分裂.
- 迪纳明的GTPase活性不仅仅是为了在囊泡分裂中产生力.
结论:
- 动氨酸作为受体介导内细胞分裂中的分子调节剂.
- 包括dynamin在内的GTPase超级家族在细胞过程中起着调节作用.
- 迪纳明的机制涉及协调的自我组装和GTPase激活,用于内细胞调节.
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