Aktは,フォークヘッドの転写因子をリン酸化し,抑制することによって細胞生存を促進します
A Brunet1, A Bonni, M J Zigmond
1Children's Hospital and Department of Neurobiology, Harvard Medical School, Boston, Massachusetts 02115, USA.
Cell
|April 2, 1999
まとめ
生存因子は,転写因子FKHRL1.1を調節することによって,細胞死を防ぐ. アクトリン酸化はFKHRL1を細胞質に保ちますが,その欠如は核の侵入とアポトーシスを引き起こす.
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.
- バイオケミストリー バイオケミストリー
背景:
- 生存因子は,Aktの活性化,BADのリン酸化,Caspase9によるアポプトシスを阻害する.
- セリン/スレオニンキナーゼAktは,細胞生存経路において重要な役割を果たします.
- アポトーシス,またはプログラム細胞死は,厳格に規制された細胞プロセスです.
研究 の 目的:
- フォークヘッド転写因子FKHRL1.1の調節におけるAktの役割を調査する.
- 生存因子がFKHRL1の活動と局所化に影響を与えるメカニズムを解明する.
- アポトーシス誘導に対するFKHRL1の貢献を決定する.
主な方法:
- タンパク質のリン酸化を検出するためのウェスタン・ブロッティング.
- タンパク質とタンパク質の相互作用 (Akt,FKHRL1,14-3-3タンパク質) を研究するための免疫プレシピテーション.
- FKHRL1の局所 (細胞質対核) を決定するサブセルラー分離.
- 定量PCRとレポーターアッセイで,標的遺伝子発現を評価する.
主要な成果:
- 生存因子の存在において,FKHRL1のアクトリン酸化物.
- リン酸化FKHRL1は14-3-3タンパク質と結合し,細胞質に留まります.
- 生存因子離脱は,FKHRL1の脱リン酸化,核転位,標的遺伝子の活性化を引き起こします.
- FKHRL1の核転位は,Fasリガンド発現を含むアポトーシスの誘導と関連しています.
結論:
- Akt媒介によるFKHRL1のリン酸化は,生存因子媒介によるアポトーシスの抑制の重要なメカニズムである.
- FKHRL1は核転位時にプロアポプトティック転写因子として作用する.
- この経路は,細胞の運命決定を制御する新しい規制軸を強調しています.
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