Rapid degradation of the G(1) cyclin Cln2 induced by CDK-dependent phosphorylation
Rapid degradation of the G(1) cyclin Cln2 induced by CDK-dependent phosphorylation
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DOI：
10.1126/science.271.5255.1597
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发表时间：
1996-03-15
期刊：
影响因子：
56.9
通讯作者：
Wittenberg, C
中科院分区：
文献类型：
--
作者：
Lanker, S;Valdivieso, MH;Wittenberg, C
细胞周期蛋白通过与细胞周期蛋白依赖性蛋白激酶（CDK）结合来调节真核生物中主要的细胞周期转换。在酵母中，G（1）细胞周期蛋白是细胞周期启动的重要限速激活剂。一种G（1）细胞周期蛋白Cln 2的G（1）特异性积累是周期性基因表达加上快速蛋白质周转的结果。CLN2的定点突变揭示了其磷酸化提供了促进快速降解的信号。Cln2磷酸化依赖于Cdc28蛋白激酶，其激活的CDK。这些发现表明，Cln2由于其激活其同源CDK亚基的能力而呈现自限性。
Cyclins regulate the major cell cycle transitions in eukaryotes through association with cyclin-dependent protein kinases (CDKs). In yeast, G(1) cyclins are essential, rate-limiting activators of cell cycle initiation. G(1)-specific accumulation of one G(1) cyclin, Cln2, results from periodic gene expression coupled with rapid protein turnover. Site-directed mutagenesis of CLN2 revealed that its phosphorylation provides a signal that promotes rapid degradation. Cln2 phosphorylation is dependent on the Cdc28 protein kinase, the CDK that it activates, These findings suggest that Cln2 is rendered self-limiting by virtue of its ability to activate its cognate CDK subunit.