MHCでコードされたトランスポーターの位置は,エンドプラズマ網膜とcis-Golgiにある
M J Kleijmeer1, A Kelly, H J Geuze
1Department of Cell Biology, School of Medicine, University of Utrecht, The Netherlands.
Nature
|May 28, 1992
まとめ
メジャー・ヒストコンパティビリティ・コンプレックス (MHC) クラスI経路は,細胞内ペプチドをT細胞に提示する. MHCクラスII領域ABCトランスポーター遺伝子によってコード化されたトランスポーター複合体は,これらのペプチドをMHCクラスIの組み立てのためにエンドプラズマの網膜に移動させます.
科学分野:
- 免疫学 免疫学とは
- 分子生物学は分子生物学である.
- 細胞生物学 細胞生物学
背景:
- メジャー・ヒストコンパティビリティ・コンプレックス (MHC) クラスIの分子は,細胞内抗原の免疫認識に不可欠です.
- これらの分子は,細胞毒性T細胞に,細胞質タンパク質から派生したペプチドを提示する.
- 以前の研究では,MHCクラスI組立のためのペプチド輸送において,MHCクラスII領域の2つのABCトランスポーター遺伝子が関与していた.
研究 の 目的:
- ペプチド輸送におけるMHCコード化されたトランスポーター複合体の役割に関するさらなる証拠を提供するため.
- このペプチドトランスポーター複合体の細胞の位置と方向を決定するために.
主な方法:
- MHCクラスI集合と抗原プレゼンテーションに欠陥がある細胞の分析.
- MHCクラスII領域内の2つのABCトランスポーター遺伝子の変異を調査した.
- トランスポーター複合体の膜の位置と方向を決定した.
主要な成果:
- MHCでコードされたABCトランスポーター遺伝子の変異は,MHCクラスIアセンブリと抗原プレゼンテーションに欠陥をもたらします.
- トランスポーター複合体は,エンドプラズマの網膜膜に局所されています.
- トランスポーター複合体は,そのATP結合ドメインがサイトゾールに面している方向に傾いている可能性が高い.
結論:
- 2つのMHC ABCトランスポーター遺伝子によってコード化されたタンパク質複合体は,細胞溶液からペプチドをエンドプラズマ網膜に輸送するトランスポーターとして機能する.
- このトランスポーター複合体は,MHCクラスI分子の組み立てに不可欠です.
- エンドプラズマ網膜の局所化とATP結合ドメインのシトゾール方向性は,活性ペプチド転位におけるその役割を支持する.
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