PICH是一种与中间体相关的SNF2家族ATPase,由Plk1调节,并且需要用于轴心检查点
Christoph Baumann1, Roman Körner, Kay Hofmann
1Department of Cell Biology, Max Planck Institute of Biochemistry, D-82152 Martinsried, Germany.
Cell
|January 16, 2007
概括
研究人员发现了Plk1-交互检查点化酶 (PICH),这是细胞分裂中的关键蛋白质,它监测姐妹基因组之间的紧张关系,以确保在分裂过程中准确的染色体分离.
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:
- 螺旋组合检查点 (SAC) 通过防止异相发生,确保精确的染色体分离,直到所有染色体都正确地附着在线粒螺旋上.
- Plk1是一个关键的激酶,参与了线粒分裂的各个阶段,包括SAC调节和染色体分离.
研究的目的:
- 确定参与线粒调节的Plk1的新型相互作用伙伴和基质.
- 为了阐明PICH在kinetochore-microtubule附件和螺杆检查点信号中的功能.
主要方法:
- 同免疫沉用于识别Plk1相互作用蛋白.
- 免疫光显微镜可视化PICH定位在分裂过程中.
- 用RNA干扰 (RNAi) 来消耗PICH,并评估其对染色体分离和螺杆检查点的影响.
- 生物化学试验分析PICH酸化和DNA结合.
主要成果:
- PICH是一种SNF2 ATPase家族成员,与Plk1.1相互作用并被Plk1.1酸化.
- 在 prometaphase 过程中,PICH 局部化到动态基因和中心基因,并在姊妹动态基因之间形成紧张依赖的线程.
- 耗尽PICH导致MAD2从kinetochores中消失,废除了螺杆检查点,并导致大量的染色体错误分离.
- 具有PICH阳性的线程代表拉伸的中间体染色质,对DNase敏感,因凝聚素损失或拓酶II抑制而加剧.
结论:
- PICH是螺旋组装检查点的一个新和必不可少的组件.
- PICH通过与中心基DNA结合来监测姐妹基因之间的紧张,从而确保精确的染色体分离.
相关概念视频
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02:19The Spindle Assembly Checkpoint
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Many proteins function together to control the spindle assembly checkpoint. Mutations affecting these proteins may allow cells to proceed into anaphase prematurely, resulting in the...
Many proteins function together to control the spindle assembly checkpoint. Mutations affecting these proteins may allow cells to proceed into anaphase prematurely, resulting in the...
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