成長因子受容体によって活性化された多様なシグナル伝達経路は,独立した遺伝子のセットではなく,広く重複する遺伝子を誘導します
D Fambrough1, K McClure, A Kazlauskas
1Whitehead Institute for Biomedical Research, Cambridge, Massachusetts 02142, USA.
Cell
|June 25, 1999
まとめ
受容体チロシンキナーゼ (RTK) 経路は,直接初期の遺伝子 (IEGs) を誘導する上で,幅広く重複しています. 特定の経路の変異は,異なる遺伝子誘導パターンを明らかにし,細胞の反応に影響を与えます.
科学分野:
- 分子生物学は分子生物学である.
- 細胞シグナリング 細胞シグナリング
- 遺伝子発現分析 遺伝子発現分析
背景:
- 受容体チロシンキナーゼ (RTK) は,下流の信号伝達経路を通じて多様な細胞プロセスを調節する重要な細胞表面受容体です.
- 直前初期遺伝子 (IEGs) は,外部刺激に対する細胞反応において重要な役割を果たす,迅速かつ一時的に活性化する遺伝子である.
- RTKシグナル伝達とIEG誘導の相互作用を理解することは,細胞の可塑性と応答機構の解読に不可欠です.
研究 の 目的:
- 活性化受容体チロシンキナーゼ (RTK) 信号伝達経路と直接初期遺伝子 (IEGs) の転写誘導の間の関係を調査する.
- フィブロブラストIEGsの誘導に責任を負う特定のRTK活性化経路を特定する.
- 線維芽細胞における異なるRTKのIEG誘導プロフィールを比較する.
主な方法:
- トランスクリプトミア分析を用いた世界的な遺伝子発現モニタリング.
- 変異性血小板由来成長因子β受容体 (PDGFRbeta) を利用して,特定のシグナル伝達経路の結合部位 (PLCgamma, PI3K, SHP2, RasGAP, Grb2) が欠けている構造を作ります.
- PDGFRbetaとフィブロブラスト成長因子受容体1 (FGFR1) によるIEG誘導の比較分析.
主要な成果:
- PDGFRbetaシグナル伝達によって誘発された66の線維芽細胞IEGを特定しました.
- PLCgamma,PI3K,SHP2,RasGAP結合部位を欠いた変異したPDGFRbeta受容体は,これらのIEGの64を誘導する部分的な能力を保持しており,重複する経路効果を示しています.
- Grb2結合部位の除去により,IEG誘導が著しく減少し,その広範な重要性を強調した.
- RasGAP結合部位を復元したPDGFRbeta変異体は,異なるインターフェロン反応性遺伝子のセットを誘導した.
- PDGFRbetaとFGFR1は,基本的に同一のIEGをフィブロブラストで誘導した.
結論:
- 複数のRTKで活性化されたシグナル伝達経路は,IEG誘導に幅広く重なり合う効果を発揮する.
- RTK経路内の特定のシグナリングコンポーネントは,異なる遺伝子セットの誘導に寄与し,細胞応答に影響を与えます.
- PDGFRbetaとFGFR1のシグナル伝達経路は,線維芽細胞における同様の初期の遺伝子セットの誘導に収束する.
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