共通のE2F-1とp73経路は,TCR活性化によって誘発された細胞死を媒介する
N A Lissy1, P K Davis, M Irwin
1Howard Hughes Medical Institute, Department of Pathology, Washington University School of Medicine, St Louis Missouri 63110, USA.
Nature
|October 18, 2000
まとめ
T細胞受容体活性化は,p53.3ではなく,E2F-1とp73経由でアポトーシスを誘発する. このプロセスは,T細胞の調節に不可欠であり,G1細胞サイクルチェックポイントが遅れて,p73を強調します.
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:
- T細胞受容体 (TCR) がサイクリングする外周T細胞を刺激すると,TCR活性化誘発細胞死 (TCR-AICD) と呼ばれるアポトーシスが誘発されます.
- TCR-AICDは,腫瘍抑制タンパク質p53とは独立して発生し,G1細胞サイクルチェックポイントが遅れている.
- アポトーシスの誘発体であるE2F-1転写因子は,その破壊がT細胞集団の増加と縮症につながるため,T細胞数の増加に役割を果たします.
研究 の 目的:
- TCR活性化誘発細胞死 (TCR-AICD) の基礎にある分子メカニズムを調査する.
- TCR媒介によるアポトーシスにおけるE2F-1とp73の役割を決定する.
- TCR-AICDに含まれる細胞サイクルチェックポイントを明らかにする.
主な方法:
- TCR-AICDを受けたT細胞における遺伝子発現の分析.
- 主要負のタンパク質 (E2F-1,p73,E2F-2,E2F-4,p53) をT細胞に導入する.
- 遺伝子ゼロのT細胞 (E2F-1-null,p73-null) でのTCR媒介によるアポトーシスの評価.
主要な成果:
- TCR-AICDを受けたT細胞は,p53に関連する遺伝子p73.3を誘導する.
- 支配的負のE2F-1またはp73タンパク質はT細胞をTCR媒介によるアポトーシスから保護したが,支配的負のE2F-2,E2F-4またはp53はそうしなかった.
- E2F-1-nullまたはp73-nullのプライマリT細胞は,TCR媒介によるアポトーシスを受けませんでした.
結論:
- TCR-AICDは,E2F-1とp73の両方の活動に依存する,G1細胞周期の遅いチェックポイントから発生します.
- p53とは異なり,p73は受容体媒介のアポプトシス刺激を統合する.
- これらの発見は,T細胞アポトーシスを調節するための新しい経路を明らかにしています.
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