ACF,一个含有ISWI和利用ATP的染色质组合和重塑因子
1Department of Biology, University of California, San Diego, La Jolla 92093-0347, USA.
Cell
|July 11, 1997
概括
我们净化和表征了ACF,这是一种ATP依赖因子,对于染色质组装和重塑至关重要. ACF有助于核子组阵列的形成,并调节色素结构,这表明它在转录激活中起着催化作用.
科学领域:
- 分子生物学分子生物学
- 染色体动力学 染色体动力学
- 基因规则 基因规则
背景情况:
- 染色体结构在调节基因表达方面发挥着至关重要的作用.
- 使用ATP的染色体组合和重塑因素是维持和改变染色体结构的关键因素.
- 已知含有ISWI的因子,如NURF,参与染色体组织.
研究的目的:
- 为了净化和表征一种新的利用ATP的染色质组合和重塑因子,称为ACF.
- 研究ACF在依赖ATP的染色质组装和重塑过程中的作用.
- 为了确定ACF是否在染色质动态和转录激活中具有催化作用.
主要方法:
- 净化ACF多个子单位因子.
- 生物化学测试用于使用纯化的ACF和基因素辅助子 (NAP-1,CAF-1) 的染色体组合.
- 染色体重塑试验用于评估ACF对核细胞间距和促进体特异性核细胞重构 (使用Gal4-VP16) 的影响.
主要成果:
- 净化了ACF,并将其描述为含有ISWI蛋白的多子单元因子,与NURF不同.
- 纯化的ACF,带着一个歇斯顿伴侣,以一种依赖ATP的方式高效地组装周期性核细胞组.
- ACF证明了核细胞间隔的ATP-依赖调节和调节的促剂特异性核细胞重构.
结论:
- ACF是一种新的ATP利用因子,对染色质组装和重塑都至关重要.
- 在核组合形成和重塑过程中,ACF具有催化作用.
- ACF的功能表明它在转录激活所需的核细胞重构中起着重要作用.
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