一个240kd的多子单元蛋白质复合体,CBF3,是开花的酵母中间体的一个主要组成部分
1Department of Biological Sciences, University of California, Santa Barbara 93106.
Cell
|February 22, 1991
概括
发芽的酵母中间体/kinetochore蛋白质复合体CBF3被净化和特征. 这个关键复合体需要酸化和组装因子,以便特定地结合到中心分子DNA.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 遗传学 是一个遗传学.
背景情况:
- 在细胞分裂过程中,中间体和基因组对染色体分离至关重要.
- 发芽酵母 (Saccharomyces cerevisiae) 为研究这些复杂结构提供了一个模型系统.
- CBF3是一种已知的蛋白质复合体,参与酵母中位素功能.
研究的目的:
- 为了净化和描述来自S. cerevisiae的CBF3蛋白质复合体.
- 调查CBF3.3的DNA结合特性和要求.
- 确定CBF3复合体的子单元及其作用.
主要方法:
- 亲和染色法用于蛋白质净化.
- 用野生类型和突变型中位素DNA进行了DNA结合测试.
- 使用DNase I足迹来确定DNA结合部位.
- 用酸酶治疗来评估酸化的作用.
主要成果:
- CBF3被净化为240kd多子单元复合体,其中包括CBF3A (110kd),CBF3B (64kd) 和CBF3C (58kd).
- CBF3 特别结合野生类型酵母中位基因组DNA (CEN),但不结合突变的 CEN DNA 与改变的 CDEIII 序列.
- 纯化的CBF3需要一个装配因子/配合因子来进行DNA结合.
- 化CBF3亚单元对于DNA结合是必要的,因为酶治疗会使复合物失活.
- 一个56bp区域,包括26bp的CDEIII共识,受到CBF3结合的保护.
结论:
- CBF3是酵母细胞中聚胺结合的必不可少的多子单元复合体.
- 酸化和特定的DNA序列 (CDEIII) 对CBF3功能至关重要.
- 需要对CBF3子单元和组装因子进行进一步的描述.
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