人类环素A是腺病毒E1A关联蛋白p60,与环素B的行为不同
1Molecular Biology and Virology Laboratory, Salk Institute for Biological Studies, San Diego, California 92138.
Nature
|August 23, 1990
概括
环A和B是细胞循环中的关键蛋白质. 这项研究揭示了环林A水平在细胞周期中波动,在环林B之前,并与一个不同的激酶相关联.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 循环素是细胞循环进展至关重要的蛋白质,循环合成和降解.
- 环林与线粒分裂诱导有关,并与p34cdc2.2.一起构成线粒分裂促进因子 (MPF) 的一部分.
- 根据保存的图案,旋被分为A类和B类.
研究的目的:
- 为了研究细胞循环调节和人类环林A的结合伙伴.
- 为了比较细胞循环期间A环和B环的表达模式.
- 描述环林A相关复合物的酶活性.
主要方法:
- 克隆人类的A和B环素.
- 在整个细胞循环中分析循环A和BmRNA和蛋白质水平.
- 生物化学试验以确定环素A复合物的激酶活性.
- 免疫沉以确定相关的蛋白质.
主要成果:
- 人类循环A mRNA和蛋白质水平表现出细胞循环依赖的变异.
- 在细胞周期期间,B环素水平之前,A环素水平上升和下降.
- 环素A形成了一个与p34cdc2不同的33kDa蛋白质复合体,表现出素H1激酶活性.
- 环素A被识别为p60,与p34cdc2在介相中和转化细胞中的腺病毒E1A结合在一起.
结论:
- 环素A在细胞循环进展中起着独特的作用,其表达在环素B之前.
- 环林A-p33复合体代表了一种参与细胞循环调节的新激酶活性.
- 环素A与不同的合作伙伴 (p34cdc2,腺病毒E1A) 的关联表明正常和转化细胞中的功能多样化.
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