Department of Biological Sciences; and Warwick University; Coventry, UK.
Organogenesis. 2009 Oct;5(4):201-10. doi: 10.4161/org.5.4.9973.
The Xenopus laevis cyclin dependent kinase inhibitor p27(Xic1) has been shown to be involved in exit from the cell cycle and differentiation of cells into a quiescent state in the nervous system, muscle tissue, heart and retina. We show that p27(Xic1) is expressed in the developing kidney in the nephrostomal regions. Using overexpression and morpholino oligonucleotide (MO) knock-down approaches we show normal levels of p27(Xic1) regulate pronephros organ size by regulating cell cycle exit. Knock-down of p27(Xic1) expression using a MO prevented myogenesis, as previously reported; an effect that subsequently inhibits pronephrogenesis. Furthermore, we show that normal levels of p27(Xic1) are required for somite segmentation also through its cell cycle control function. Finally, we provide evidence to suggest correct paraxial mesoderm segmentation is not necessary for pronephric induction in the intermediate mesoderm. These results indicate novel developmental roles for p27(Xic1), and reveal its differentiation function is not universally utilised in all developing tissues.
爪蟾细胞周期蛋白依赖性激酶抑制剂 p27（Xic1）已被证明参与细胞周期退出和神经系统、肌肉组织、心脏和视网膜中的细胞分化为静止状态。我们表明，p27（Xic1）在肾单位区域的发育肾脏中表达。通过过表达和反义寡核苷酸（MO）敲低方法，我们表明 p27（Xic1）的正常水平通过调节细胞周期退出来调节肾单位器官大小。以前的报道表明，使用 MO 敲低 p27（Xic1）的表达可阻止肌发生，这随后抑制了肾发生。此外，我们还表明，p27（Xic1）的正常水平通过其细胞周期控制功能也需要体节分段。最后，我们提供的证据表明，正确的轴旁中胚层分段对于中胚层中的肾原基诱导不是必需的。这些结果表明 p27（Xic1）具有新的发育作用，并揭示其分化功能并非在所有发育组织中都普遍利用。
