Centre for Gene Regulation and Expression, College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK.
Dev Cell. 2013 Aug 26;26(4):381-92. doi: 10.1016/j.devcel.2013.06.014. Epub 2013 Aug 8.
PHD1 belongs to the family of prolyl-4-hydroxylases (PHDs) that is responsible for posttranslational modification of prolines on specific target proteins. Because PHD activity is sensitive to oxygen levels and certain byproducts of the tricarboxylic acid cycle, PHDs act as sensors of the cell's metabolic state. Here, we identify PHD1 as a critical molecular link between oxygen sensing and cell-cycle control. We show that PHD1 function is required for centrosome duplication and maturation through modification of the critical centrosome component Cep192. Importantly, PHD1 is also required for primary cilia formation. Cep192 is hydroxylated by PHD1 on proline residue 1717. This hydroxylation is required for binding of the E3 ubiquitin ligase SCF(Skp2), which ubiquitinates Cep192, targeting it for proteasomal degradation. By modulating Cep192 levels, PHD1 thereby affects the processes of centriole duplication and centrosome maturation and contributes to the regulation of cell-cycle progression.
PHD1 属于脯氨酰-4-羟化酶(PHD)家族,负责特定靶蛋白上脯氨酸的翻译后修饰。由于 PHD 活性对氧水平和三羧酸循环的某些副产物敏感,因此 PHD 作为细胞代谢状态的传感器。在这里,我们确定 PHD1 是氧感应和细胞周期控制之间的关键分子联系。我们表明,PHD1 功能通过修饰关键的中心体成分 Cep192 来控制中心体复制和成熟。重要的是,PHD1 对于初级纤毛的形成也是必需的。PHD1 在 Cep192 的脯氨酸残基 1717 上羟化。这种羟化作用是 E3 泛素连接酶 SCF(Skp2)结合所必需的,SCF 将 Cep192 泛素化,将其靶向蛋白酶体降解。通过调节 Cep192 的水平,PHD1 从而影响中心体复制和中心体成熟的过程,并有助于调节细胞周期进程。