Laboratory of Immunology, Centre hospitalier de l'Université de Montréal (CRCHUM)-Hôpital Notre-Dame, Montreal, Quebec, Canada.
FEBS Lett. 2010 Nov 19;584(22):4623-6. doi: 10.1016/j.febslet.2010.10.030. Epub 2010 Oct 21.
Ran (Ras-related nuclear protein), a Ras family GTPase, is involved in multiple cellular functions, including the regulation of DNA replication, cell cycle progression, nuclear structure formation, RNA processing-exportation, and nuclear protein importation. Ran(+/-) embryonic stem (ES) cells were produced in an attempt to generate Ran null mutant mice. Even after an extremely large number of blastocyst injections, no Ran(+/-) chimeric mice could be generated. Ran(+/-) ES cell-derived fibroblasts showed reduced Ran protein expression, and manifested augmented nuclear abundance of AP-1 factors (c-Jun and c-Fos) upon cytokine stimulation. Our experiments demonstrated that intracellular Ran protein levels controlled the nuclear presence of certain transcription factors, such as c-Fos and c-Jun.
Ran（Ras-related nuclear protein）是 Ras 家族 GTPase 的一种，参与多种细胞功能，包括 DNA 复制、细胞周期进程、核结构形成、RNA 加工-输出以及核蛋白输入的调节。Ran(+/-)胚胎干细胞（ES 细胞）的产生是为了试图生成 Ran 缺失突变体小鼠。即使经过大量的囊胚注射，也无法生成 Ran(+/-)嵌合小鼠。Ran(+/-)ES 细胞衍生的成纤维细胞显示出 Ran 蛋白表达减少，并且在细胞因子刺激下，AP-1 因子（c-Jun 和 c-Fos）的核内丰度增加。我们的实验表明，细胞内 Ran 蛋白水平控制着某些转录因子（如 c-Fos 和 c-Jun）在核内的存在。
