通过将极光B基因酶与kinetochore基质空间分离来感知染色体双向
Dan Liu1, Gerben Vader, Martijn J M Vromans
1Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA.
Science (New York, N.Y.)
|January 20, 2009
概括
细胞分裂需要适当的染色体附着. 这项研究表明,中心粒体的物理紧张信号显示出Aurora B激酶活性,确保细胞分裂的正确染色体螺旋连接.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- 成功的细胞分裂取决于精确的染色体轴附着 (双导向).
- 极光B激酶对于通过酸化激素基质来调节这些附着物至关重要.
- 中心分子张力转化为信号以稳定附着的机制尚不清楚.
研究的目的:
- 为了研究中心体中的物理力量是如何被感知并转化为信号通路的.
- 确定 Aurora B 激酶及其基质之间的空间分离在调节染色体双导向中的作用.
主要方法:
- 利用基于光共振能量转移 (FRET) 的生物传感器来测量活细胞中的局部酸化动态.
- 操纵了Aurora B激酶与kinetochore基质的空间距离.
主要成果:
- 由Aurora B基因酶的Kinetochore基底酸化取决于基因酶和基底之间的距离.
- 增加极光B和kinetochore基板之间的空间分离减少了酸化.
- 减少Aurora B和kinetochore基板之间的距离,防止了双方向附件的稳定,并激活了螺旋组装检查点.
结论:
- 通过将Aurora B基因酶与其基因基质的空间分离来感知中介质张力.
- 这种空间分离减少了基质酸化,导致了动脉管微管的稳定和适当的染色体附着.
- 这些发现为机械力量如何调节细胞分裂忠实性提供了一个新的机制.
相关概念视频
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