通过OCA-S激活 histone H2B促进体的S阶段激活,OCA-S是一种含有GAPDH作为关键成分的联合激活体复合体
Lei Zheng1, Robert G Roeder, Yan Luo
1Laboratory of Biochemistry and Molecular Biology, The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA.
Cell
|July 31, 2003
概括
研究人员确定了OCA-S,这是一个蛋白质复合体,对S阶段依赖的组织素H2B转录至关重要. 它的成分p38,是甘甲基-3-酸盐脱酶的核形式,结合Oct-1并将转录与细胞循环调节和代谢状态联系起来.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 生物化学 生物化学
背景情况:
- 细胞周期期间,基因转录在细胞基因转录中受到严格调节,特别是在DNA复制的S阶段.
- Oct-1是一种转录因子,参与调节各种细胞过程,包括基因表达的基因表达.
研究的目的:
- 为了识别和表征参与S相依赖的 histone H2B转录的联合激活剂.
- 阐明将基因表达链接到细胞循环调节和细胞代谢的分子机制.
主要方法:
- 共同免疫沉以确定蛋白质相互作用.
- 染色体免疫沉以评估促进体的招募.
- 在体外和体内活体转录试验.
- 生物化学试验用于研究酶活性和辅因子依赖性.
主要成果:
- 隔离和鉴定了OCA-S,这是一种对S相依赖的组合素H2B转录至关重要的多元组件协活性剂.
- 确定p38是OCA-S的关键组成部分,它结合Oct-1并在S阶段被招募到H2B促进体中.
- 证明p38是甘甲基-3-酸盐脱酶的核形式,其功能由NAD (((+) 和NADH调节.
- 表明OCA-S与NPAT相互作用,将基因组转录与细胞周期调节器联系起来.
结论:
- OCA-S 是 S 阶段特异性 ヒ斯 H2B 转录的关键调节者.
- 这些发现通过OCA-S的p38组件将基因转录与细胞周期控制和细胞氧化还原状态联系起来.
- 这项工作为理解协调的基因组基因表达及其与DNA复制的合提供了基础.
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