两个基因组标记确定了内部的中间体和染色体双方向
Yuya Yamagishi1, Takashi Honda, Yuji Tanno
1Laboratory of Chromosome Dynamics, Institute of Molecular and Cellular Biosciences, University of Tokyo, Yayoi, Tokyo 113-0032, Japan.
Science (New York, N.Y.)
|October 9, 2010
概括
两个基因素激酶,Haspin和Bub1,合作将染色体乘客复合体 (CPC) 准到内心的中间体. 这种精确的准确保了细胞分裂期间适当的染色体分离.
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:
- 分离过程中精确的染色体分离依赖于染色体乘客复合体 (CPC).
- 含有Aurora B和survivin的CPC必须定位到内部的中间体才能正常工作.
- 定义内部中间体和指导CPC局部化的分子机制在很大程度上仍未被阐明.
研究的目的:
- 调查基于染色体乘客复合体 (CPC) 向内心中心粒的分子机制.
- 确定定义内心中间体和招募CPC的关键因素和修改.
主要方法:
- 使用了裂变酵母和人类细胞模型.
- 研究的基因组修饰,特别是由Haspin对基因组H3-threonine 3 (H3-pT3) 和Bub1.1对基因组2A-serine 121 (H2A-S121) 的酸化.
- 分析了CPC组件 (幸存者) 和适配器 (shugoshin) 与修饰核体的结合相互作用.
- 检查了Haspin,Bub1,cohesin和Pds5在细胞内的定位.
主要成果:
- 证明了哈斯介导的H3-pT3和Bub1介导的H2A-S121酸化合作,将CPC准到内心的中间体.
- 表明H3-pT3促进了幸存者与核细胞结合.
- 发现H2A-S121酸化促进了舒戈辛的结合.
- 发现Haspin通过Pds5与凝聚素同位,而Bub1则在kinetochores定位.
结论:
- 内心中间体是由两个不同的激素激酶活动的交叉点定义的:Haspin和Bub1.1.
- 这种双酶机制确保了CPC精确地被招募到内心的中间体,这对于忠实的染色体分割至关重要.
- 这些发现为中粒体组织和线粒体调节提供了新的理解.
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