ダイナミンのGAPドメインの障害は,受容体媒介性エンドサイトーシスを刺激する
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
まとめ
ダイナミンタンパク質の自己組み立ては,細胞の膀形成を調節する. この研究では,ダイナミンは受容体媒介性エンドサイトーシスにおいて,力発生器ではなく分子調節器として作用することを明らかにしています.
科学分野:
- 細胞生物学 細胞生物学
- 分子生物学と構造生物学について
- バイオケミストリー バイオケミストリー
背景:
- ダイナミンは,クラスリン媒介性エンドサイトーシスに不可欠なGTP水解タンパク質です.
- ダイナミンは,体外および体内において,カラーに自己組み立てられ,そのGTPase活性を刺激します.
- 以前,ダイナミンはGTPの水解を用いて,膀分裂のための力を生み出すと提案されていた.
研究 の 目的:
- ダイナミンの自己組み立てのメカニズムと,エンドサイトーシスにおけるその役割を解明する.
- ダイナミンのGTPase活性化ドメインの機能を調査するために.
- ダイナミンがGTPアゼの力生成体または分子調節体として作用するかどうかを判断する.
主な方法:
- ダイナミンの自己組み立てとGTPaseの活性を in vitroとin vivoで研究した.
- 自己組み立て刺激のGTPase活性に欠陥があるダイナミン変異体を使用した.
- これらの変異体の過剰発現が受容体媒介性エンドサイトーシスに与える影響を観察した.
主要な成果:
- ダイナミンの自己組み立ては,特定のGTPase活性化ドメインによって調整されます.
- 自己組み立てに刺激されたGTPase活性がないダイナミン変異体の過剰発現は,内分細胞分裂を加速した.
- ダイナミンのGTPaseの活動は,膀分裂における力生成に限ったものではありません.
結論:
- ダイナミンは,受容体媒介性エンドサイトーシスにおける分子調節剤として機能する.
- ダイナミンを含むGTPaseスーパーファミリーは,細胞プロセスにおける規制的な役割を果たします.
- ダイナミンのメカニズムは,内細胞調節のための調整された自己組み立てとGTPaseの活性化を含む.
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