一种基因编码的可光激活的Rac控制着活细胞的运动性
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
概括
研究人员开发了可光激活的Rac1 (PA-Rac1) 来精确控制使用光的细胞行为. 这种基因编码的工具允许对Rac1活动进行可逆操纵,影响细胞运动和细胞骨动力学.
科学领域:
- 细胞生物学 细胞生物学
- 生物化学 生物化学
- 分子生物学分子生物学
背景情况:
- 在空间和时间中精确控制蛋白质活动对于细胞行为至关重要,但仍然具有挑战性.
- 现有的光诱导蛋白激活方法通常涉及有毒的紫外线,不可逆转的变化或侵入性细胞加载技术.
研究的目的:
- 开发一个基因编码的,可光激活的Rac1 (PA-Rac1) 进行精确的时空控制的actin细胞骨动力学.
- 研究Rac1在细胞运动,突起形成和RhoA.调节中的作用.
主要方法:
- 通过将Rac1突变体与光氧电压 (LOV) 域融合,对可光激活的Rac1 (PA-Rac1) 进行遗传编码.
- 使用可见光 (458或473nm) 进行可逆的PA-Rac1.1激活和失活.
- 使用PA-Rac1诱导局部细胞突起,,并控制细胞运动方向.
主要成果:
- 使用可见光,PA-Rac1启用了可逆和可重复的激活,导致精确局部化的细胞突起和.
- 局部Rac1激活/非激活控制细胞运动和方向性,肌酸素参与方向性,PAK参与突起.
- PA-Rac1 发现,Rac1 在小鼠胚胎纤维细胞中抑制RhoA,这种抑制在突起和纹上受到调节.
结论:
- 基因编码的PA-Rac1为Rac1活动和细胞骨动态的时空控制提供了一个强大的,非侵入性的工具.
- Rac1在细胞突起,运动和定向方面发挥着关键作用,并抑制RhoA活动.
- 对LOV-Rac相互作用的洞察力有助于将这种光激活技术扩展到其他蛋白质.
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