一个依赖ATP的核细胞重塑因子的净化和特性
1Laboratory of Biochemistry, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-4255, USA.
Cell
|December 15, 1995
概括
研究人员净化了一种核细胞重塑因子 (NURF),该因子利用ATP改变染色体结构. NURF与GAGA因子相互作用,表明转录的不同染色质重塑系统.
科学领域:
- 分子生物学分子生物学
- 生物化学 生物化学
- 遗传学 是一个遗传学.
背景情况:
- 染色体结构在调节基因转录中起着至关重要的作用.
- 取决于ATP的核细胞重塑因子对于改变染色质可访问性至关重要.
- 了解这些因素是解读基因表达控制的关键.
研究的目的:
- 为了净化和描述Drosophila的一种新型ATP依赖的核细胞重塑因子 (NURF).
- 为了研究NURF在hsp70促进体中重塑色素的机制.
- 为了将NURF的特性与其他已知的染色体重塑复合体进行比较.
主要方法:
- 从Drosophila胚胎提取物中净化NURF.
- 生物化学测试以确定ATPase活性和基质特异性.
- 对NURF与GAGA转录因子和染色素相互作用的分析.
主要成果:
- 净化了NURF,发现它至少由四种多组成.
- NURF利用ATP水解,其活性由核细胞刺激.
- NURF与GAGA因子协同作用,在hsp70促进体上修改染色质结构.
- NURF的特性与SWI2/SNF2复合体有所不同,这表明它具有不同的重塑机制.
结论:
- 一种新的ATP依赖的核细胞重塑因子NURF已经被识别和净化.
- 通过ATPase活动,NURF直接扰乱核体结构.
- 这些发现表明,在转录中至少存在两个不同的ATP依赖的染色质重塑系统.
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