相关实验视频
Updated: Jul 11, 2026
04:36
Assay for Adhesion and Agar Invasion in S. cerevisiae
Published on: November 8, 2006
概括
细胞周期进展依赖于CDC28激酶活性,这种活性是G1阶段特有的. 在进入S阶段或交配时,活动会消失,这表明需要一个激活因子.
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:
- CDC28基因产物是酵母细胞周期的关键调节者.
- 已知一种40kDa的多与CDC28基因产物结合在一起.
研究的目的:
- 为了研究细胞周期期间CDC28蛋白激酶活性的调节.
- 确定控制40kDa聚的特定酸化的因素.
主要方法:
- 免疫复合物沉以分离CDC28基因产物.
- 在体外激酶试验测量40kDa聚的酸化.
- 使用不同细胞周期阶段和突变物的提取物进行补充试验.
主要成果:
- 通过p40酸化测量CDC28蛋白激酶活性,仅在分裂的G1期细胞中检测到.
- 当细胞离开G1进入S阶段或前结合状态时,活动就会丧失.
- 来自非G1细胞的提取物缺乏可交换的激活因子,而静止和费洛蒙处理的细胞含有这种因子,但具有非活性激酶.
- 缺乏cAMP的突变体表现出类似于静止细胞的特征.
结论:
- CDC28蛋白激酶活性受到严格调节,并且仅限于细胞周期的G1阶段.
- 细胞循环的进展是由可交换的激活因子的存在和活性控制的CDC28激酶.
- 这种激酶的调节对于防止进入S阶段或在不适当的条件下发生交配至关重要.
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