Ciciarello M, Mangiacasale R, Lavia P
Institute of Molecular Biology and Pathology, CNR National Research Council, c/o University La Sapienza, Via degli Apuli 4, 00185 Rome, Italy.
Cell Mol Life Sci. 2007 Aug;64(15):1891-914. doi: 10.1007/s00018-007-6568-2.
Mitosis is the most potentially dangerous event in the life of a cell, during which the cell genetic identity is transmitted to daughters; errors at this stage may yield aneuploid cells that can initiate a genetically unstable clone. The small GTPase Ran is the central element of a conserved signaling network that has a prominent role in mitotic regulation. Pioneering studies with amphibian oocytes indicated that Ran, in the GTP-bound form, activates factors that regulate spindle assembly and dynamics. An increasing body of data indicate higher specificity and complexity in mitotic control operated by Ran in somatic cells. Newly identified target factors of Ran operate with different specificity, and it is emerging that mitotic progression requires the precise positioning of Ran network components and effectors at specific sites of the mitotic apparatus according to a highly regulated schedule in space and time. In this review we summarize our current understanding of Ran control of mitosis and highlight the specificity of mechanisms operating in mammalian somatic cells.
有丝分裂是细胞生命中最具潜在危险的事件，在此过程中细胞的遗传特性传递给子代细胞；此阶段的错误可能产生非整倍体细胞，进而引发基因不稳定的克隆。小GTP酶Ran是一个保守信号网络的核心元件，在有丝分裂调控中发挥着重要作用。对两栖类卵母细胞的开创性研究表明，结合GTP的Ran可激活调节纺锤体组装和动态变化的因子。越来越多的数据表明，Ran在体细胞有丝分裂控制中具有更高的特异性和复杂性。新发现的Ran靶因子具有不同的特异性，并且有丝分裂进程似乎需要Ran网络组件和效应器根据高度调控的时空时间表精确地定位在有丝分裂装置的特定部位。在这篇综述中，我们总结了目前对Ran控制有丝分裂的理解，并强调了在哺乳动物体细胞中发挥作用的机制的特异性。
