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MHCクラスI/β2マイクログローブリン複合体は,ペプチド結合の前にTAPトランスポーターと結合する
B Ortmann1, M J Androlewicz, P Cresswell
1Section of Immunobiology, Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, Connecticut 06520.
Nature
|April 28, 1994
まとめ
抗原処理 (TAP) に関連するトランスポーターは,主要な組織適合性複合体,クラスIペプチド複合体の組み立てに不可欠です. TAP分子はクラスI/β2マイクログローブリンジマーと結合し,免疫認識のためのペプチド結合を促進します.
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,抗原性ペプチドを細胞毒性Tリンパ球に提示する.
- ペプチド生成にはプロテアソームが関与し,エンドプラズマ網膜 (ER) への輸送は,抗原処理 (TAP) に関連するトランスポーターによって媒介されます.
研究 の 目的:
- MHCクラスI/β2-マイクログローブリン (β2m) ペプチド複合体の組み立てにおけるTAP分子の役割を調査する.
- ER内のMHCクラスI,β2m,calnexin,およびTAPの相互作用を解明する.
主な方法:
- ヒトB細胞系統のER内のタンパク質-タンパク質相互作用の分析.
- MHCクラスI重鎖,β2m,calnexin,TAPの関連性を調査しています.
主要な成果:
- 無料のMHCクラスI重鎖は,ERでcalnexinと関連しています.
- 人間のB細胞系では,MHCクラスI/β2mジメルは,カルネキシンではなく,TAPと結合する.
- TAPがMHCクラスI/β2mジマーと結合すると,ペプチド結合が容易になる.
結論:
- カルネキシンは,MHCクラスIとβ2mの二酸化を媒介する.
- TAP分子は,ダイマーと結合し,ペプチド結合を促進することによって,MHCクラスIペプチド複合体の組み立てに直接的な役割を果たします.
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