通过SWR1逐步替换基因组,需要与基因组H2A.Z和正规核细胞组进行双重激活
Ed Luk1, Anand Ranjan, Peter C Fitzgerald
1Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA. luked@mail.nih.gov
Cell
|November 30, 2010
概括
在促进体上,SWR1复合体用H2A.Z替换了组 histone H2A. 这项研究揭示了SWR1
科学领域:
- * 分子生物学 * 分子生物学
- * 表观遗传学 是一种表观遗传学.
- * 染色体生物学
背景情况:
- * 质子变异H2A.Z对于真核生物促进体调节至关重要.
- *SWR1复合物通过依赖ATP的质子交换促进H2A.Z的结合.
- *SWR1介导的H2A.Z沉积的精确机制仍然不完全理解.
研究的目的:
- * 阐明由SWR1复合体取代H2A.Z的机制.
- * 为了研究H2A.Z核细胞组在促进体区域的异质性.
- * 为了确定SWR1 ATPase活性在基因素交换中的作用.
主要方法:
- *使用纯化的SWR1复合体和核细胞体进行了体外生化分析.
- *核细胞组合的分析和基因组变异体质量学.
- * 描述SWR1 ATPase活性对不同基质的反应.
主要成果:
- *促体-近端核细胞体在H2A.Z含量方面表现出显著的异质性.
- *SWR1催化H2A.Z的替代逐步发生,形成异型和同型核细胞.
- *SWR1 ATPase活动由含有H2A的核细胞和自由的H2A.Z-H2B二元体刺激,驱动H2A驱逐和H2A.Z沉积.
结论:
- *SWR1复合体介于单向的,逐步的H2A.Z替换.
- * H2A.Z含量的核异质性是促进体近位区域的特征.
- * 含有H2A的核细胞和自由的H2A.Z-H2B二极体之间的相互作用决定了SWR1在质子交换中的特异性和功能.
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