低分子量GTP結合タンパク質の局所化は,エクソサイトとエンドサイトのコンパートメントに
P Chavrier1, R G Parton, H P Hauri
1European Molecular Biology Laboratory, Heidelberg, Federal Republic of Germany.
Cell
|July 27, 1990
まとめ
研究者らは,哺乳類の細胞に11のGTP結合タンパク質を特定した. rab2, rab5, rab7という3つのタンパク質は,タンパク質の輸送と内分細胞分裂に関与する特定の細胞区間に局所されました.
科学分野:
- 細胞生物学 細胞生物学
- 分子生物学は分子生物学である.
- タンパク質の密輸 タンパク質の密輸
背景:
- YPT1/SEC4遺伝子ファミリーは,酵母における膀輸送に不可欠なGTP結合タンパク質をコードする.
- これらのタンパク質の哺乳類の同種を理解することは,細胞内密輸経路の解明に不可欠です.
研究 の 目的:
- 酵母YPT1/SEC4.4と同型である哺乳類のGTP結合タンパク質を分離し,特徴づけること.
- これらの哺乳類のタンパク質がエクソサイトとエンドサイトの経路内で細胞下部位を決定する.
主な方法:
- MDCK細胞ライブラリから,推定GTP結合タンパク質をコードする11個のcDNAクローンの分離.
- タンパク質を局所化するために,親和性浄化抗体を用いた免疫光および免疫電子顕微鏡検査.
- 特定されたタンパク質に関連した細胞構造の特徴.
主要な成果:
- 哺乳類のラブ2,ラブ5,ラブ7.7を含む11の同類クローンを成功裏に分離しました.
- rab2は,ERとGolgiの間の中間コンパートメントに局限しています.
- rab5は,プラズマ膜と初期のエンドソームに局所化しています.
- rab7は後期エンドソームに局所化している.
結論:
- GTP結合タンパク質のYPT1/SEC4サブファミリーのメンバーは,哺乳類の細胞の異なる外細胞および内細胞サブコンパートメントに特異的に局所されています.
- これらの発見は,種間の細胞内密輸におけるこれらのタンパク質の保存された役割を強調しています.
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