遺伝的にコード化された光活性化Racは,生きている細胞の運動性を制御する
Yi I Wu1, Daniel Frey, Oana I Lungu
1Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina 27599, USA. yiwu@med.unc.edu
Nature
|August 21, 2009
まとめ
研究者らは,光を用いた細胞行動の正確な制御のために,光活性化Rac1 (PA-Rac1) を開発した. この遺伝子でコードされたツールは,Rac1の活性に対する可逆的な操作を可能にし,細胞の運動性と細胞骨格の動態に影響を与えます.
科学分野:
- 細胞生物学 細胞生物学
- バイオケミストリー バイオケミストリー
- 分子生物学は分子生物学である.
背景:
- 空間と時間におけるタンパク質活動の正確な制御は,細胞の行動に不可欠ですが,依然として困難です.
- 光誘発によるタンパク質活性化のための既存の方法は,しばしば有毒な紫外線,不可逆的な変化,または侵襲的な細胞負荷技術を含む.
研究 の 目的:
- アクチン細胞骨格動態の精密な時空制御のために,遺伝的にコードされた,光活性化可能なRac1 (PA-Rac1) を開発する.
- Rac1の細胞運動性,突起形成,およびRhoAの調節における役割を調査する.
主な方法:
- 光活性化Rac1 (PA-Rac1) を光酸素電圧 (LOV) ドメインとRac1変異体を融合させることで遺伝的にコードする.
- 可視光 (458nmまたは473nm) を利用して,PA-Rac1.1の可逆的な活性化および無活性化を行う.
- PA-Rac1を用いて,局所的な細胞突起,ラフリングを誘発し,細胞の移動方向を制御する.
主要な成果:
- PA-Rac1は可視光を用いた可逆かつ繰り返し活性化を可能にし,正確に局所化された細胞突起とラフリングにつながった.
- 局所Rac1の活性化/無活性化によって制御された細胞の運動性と方向性,方向性にはミオシンが関与し,突起にはPAKが関与した.
- PA-Rac1は,Rac1がマウスの胚性線維芽細胞でRhoAを阻害し,この阻害は突起やラッフルで調節されていることを明らかにしました.
結論:
- 遺伝的にコードされたPA-Rac1は,Rac1の活動と細胞骨格動態の空間時間的制御のための強力な非侵襲的なツールを提供します.
- Rac1は細胞の突起,運動,方向性において重要な役割を果たし,RhoAの活性を抑制する.
- LOV-Rac相互作用の洞察は,この光活性化技術の他のタンパク質への拡張を容易にする.
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