ホメオドメインの相互作用タンパク質キナーゼ2は,転写性コアプレッサーCtBPのダウンレギュレーションによってアポトーシスを促進する
Qinghong Zhang1, Yasuhiro Yoshimatsu, Jeffrey Hildebrand
1Vollum Institute, Oregon Health and Science University, 3181 S.W. Sam Jackson Park Road, Portland, OR 97239, USA. zhangq@ohsu.edu
Cell
|October 22, 2003
まとめ
CtBP (C末端結合タンパク質) の遺伝的ノックアウトは,アポトーシスを増加させます. 紫外線とHIPK2 (ホメオドメイン相互作用タンパク質キナーゼ2) は,CtBPレベルを低下させ,p53-欠乏細胞におけるアポトーシスを促進する.
科学分野:
- 分子生物学は分子生物学である.
- 細胞生物学 細胞生物学
- がん研究 がん研究
背景:
- トランスクリプションのコアプレッサーであるCtBP (C端末結合タンパク質) は,遺伝子発現の調節に作用する.
- マウスの胚性線維芽細胞におけるCtBPノックアウトは,アポトーシスの増加につながります.
- CtBPの調節を理解することは,アポトーシス経路の解読に不可欠です.
研究 の 目的:
- 細胞CtBPレベルを調節する経路と,アポトーシスにおけるその役割を特定する.
- CtBP,HIPK2 (ホメオドメイン相互作用タンパク質キナーゼ2) とUV誘発アポトーシスの関連性を調査する.
主な方法:
- E1A-CtBP複合体を用いてマウス胚のcDNAライブラリのスクリーニング.
- 遺伝子ノックアウト,siRNA,およびキナーゼ不活性変異体を使用して,タンパク質の機能を研究する.
- p53欠乏細胞におけるアポトーシス誘導の評価.
主要な成果:
- HIPK2はCtBPと相互作用するタンパク質として特定されました.
- HIPK2発現または紫外線照射は,プロテアソーム媒介の分解によってCtBPレベルを低下させた.
- 紫外線によるCtBP減少は,HIPK2キナーゼ活性に依存していた.
- 減少したCtBPレベルは,p53欠乏細胞でもアポトシスを促進しました.
結論:
- HIPK2媒介のCtBP分解を含むUV誘発のアポトーシスの新しい経路が解明されました.
- この経路は,p53が欠けている細胞で機能し,代替アポプトシスメカニズムについての洞察を提供します.
- 研究結果は,細胞アポトーシスの重要な要因としてCtBPの調節を強調しています.
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