G1/S 过渡中 Cyclin E 相关事件
中文名称
通路描述
G1 到 S 相位的转换由 Cyclin E:Cdk2 复合物控制。当 Cyclin E:Cdk2 复合物形成时，Cdk2 由 Wee1 和 Myt1 激酶磷酸化。这种磷酸化使 Cdk2 保持无活性。在酵母中，这种控制称为细胞大小检查点控制。Cdk2 的去磷酸化由 Cdc25A 激活，并与细胞达到适当大小以及 DNA 合成机器准备好相协调。Cdk2 然后磷酸化 G1/S 特异性蛋白，包括 DNA 复制起始所需的蛋白。S 阶段的开始由 DNA 复制早期启动的原点上的第一个核苷酸被放置在引物上标记。Cyclin E 蛋白在细胞中的含量由泛素介导的蛋白降解控制（参见 Woo, 2003）。该通路尚未在 Reactome 中注释。
英文描述
Cyclin E associated events during G1/S transition The transition from the G1 to S phase is controlled by the Cyclin E:Cdk2 complexes. As the Cyclin E:Cdk2 complexes are formed, the Cdk2 is phosphorylated by the Wee1 and Myt1 kinases. This phosphorylation keeps the Cdk2 inactive. In yeast this control is called the cell size checkpoint control. The dephosphorylation of the Cdk2 by Cdc25A activates the Cdk2, and is coordinated with the cells reaching the proper size, and with the DNA synthesis machinery being ready. The Cdk2 then phosphorylates G1/S specific proteins, including proteins required for DNA replication initiation. The beginning of S-phase is marked by the first nucleotide being laid down on the primer during DNA replication at the early-firing origins.Failure to appropriately regulate cyclin E accumulation can lead to accelerated S phase entry, genetic instability, and tumorigenesis. The amount of cyclin E protein in the cell is controlled by ubiquitin-mediated proteolysis (see Woo, 2003).This pathway has not yet been annotated in Reactome.
所含基因
28 个基因