中心极光B激活需要TD-60,微管和基质原始酸化
Sara E Rosasco-Nitcher1, Weijie Lan, Sepideh Khorasanizadeh
1Department of Biochemistry and Molecular Genetics, University of Virginia Medical School, Charlottesville, VA 22908, USA.
Science (New York, N.Y.)
|January 26, 2008
概括
染色体乘客复合体 (CPC) 被TD-60和微管类等辅因子激活,并通过基质酸化来缓解. 这揭示了Aurora-B激酶是如何调节线粒分裂的.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 染色体乘客复合体 (CPC) 对于在线粒分裂过程中准确的细胞分裂至关重要.
- 欧罗拉-B激酶是CPC的催化子单元,它控制着诸如染色体对齐和螺杆检查点信号等关键过程.
- 了解奥罗拉-B激酶激活是理解线粒调节的关键.
研究的目的:
- 阐明调节 Aurora-B 激酶激活的独特机制.
- 研究辅助因子和基质相互作用在控制 Aurora-B 活动中的作用.
主要方法:
- 在体外激酶测试以确定 Aurora-B 激活的辅因子要求.
- 调查 Aurora-B 基质,Plk1,Haspin 和 TD-60 定位在中间体之间的相互作用.
主要成果:
- 在体外激活Aurora-B需要辅因子电相盘-60kD (TD-60) 和微管.
- TD-60将CPC和Haspin激酶定位到中间体,调节Aurora-B活动.
- 通过Plk1和Haspin对Aurora-B基质的酸化缓解了基质介导的Aurora-B激活的抑制.
结论:
- 控制 Aurora-B 激酶激活的有两个不同的机制:辅因子依赖激活和基质介导抑制的缓解.
- 这些发现提供了关于Aurora-B如何在非对齐的染色体和 merotelic 附着过程中化中心基质的见解.
- 该研究提出了Aurora-B调节的模型,强调了中心位点定位和基质反循环的重要性.
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