Activation of M-phase-specific histone H1 kinase by modification of the phosphorylation of its p34cdc2 and cyclin components.
Activation of M-phase-specific histone H1 kinase by modification of the phosphorylation of its p34cdc2 and cyclin components.
复制标题
通过修饰 p34cdc2 和细胞周期蛋白成分的磷酸化来激活 M 期特异性组蛋白 H1 激酶。
DOI：
10.1101/gad.4.1.9
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发表时间：
1990
影响因子：
10.5
通讯作者：
Beach,D
中科院分区：
文献类型：
--
作者：
Pondaven,P;Meijer,L;Beach,D
M期特异性组蛋白H1激酶（H1 K）在细胞分裂周期中经历G2/M转换的多种真核细胞类型中已被描述。我们使用p13 suc 1-Sepharose亲和层析从成熟的海星卵母细胞中纯化H1 K至接近均一。获得67%的产率。活性H1 K表现为90- 100-kD蛋白，似乎由等摩尔量的细胞周期蛋白和p34 cdc 2组成。当卵母细胞进入M期时，H1 K被激活，p34 cdc 2亚基被酪氨酸去磷酸化，而细胞周期蛋白亚基被酪氨酸去磷酸化。非活性p34 cdc 2/细胞周期蛋白复合物的酸性磷酸酶处理诱导p34 cdc 2去磷酸化和酶活性的三至八倍刺激。这些结果表明，活跃的M期特异性H1 K由去磷酸化的p34 cdc 2和磷酸化的cyclin组成。
An M-phase-specific histone H1 kinase (H1K) has been described in a wide variety of eukaryotic cell types undergoing the G2/M transition in the cell division cycle. We have used p13suc1-Sepharose affinity chromatography to purify H1K to near homogeneity from matured starfish oocytes. A yield of 67% was obtained. Active H1K behaves as a 90- to 100-kD protein and appears to be constituted of equimolar amounts of cyclin and p34cdc2. The p34cdc2 subunit becomes tyrosine-dephosphorylated as the H1K is activated during entry of the oocytes into M phase, whereas the cyclin subunit is reciprocally phosphorylated. Acid phosphatase treatment of inactive p34cdc2/cyclin complex induces p34cdc2 dephosphorylation and three- to eightfold stimulation of the enzyme activity. These results suggest that active M-phase-specific H1K is constituted of both dephosphorylated p34cdc2 and phosphorylated cyclin.