Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden.
Cell Death Dis. 2012 Jan 19;3(1):e357. doi: 10.1038/cddis.2011.138.
We have recently found that primary rat embryonic fibroblasts (REFs) could be immortalized by overexpression of the human mitochondrial ribosomal protein MRPS18-2 (S18-2). A derived cell line, designated 18IM, expressed the embryonic stem cell markers SSEA-1 and Sox2. Upon inoculation into severe combined immunodeficiency mice, 18IM cells differentiated to express pan-keratin. They were not tumorigenic. Here we report the gene profiling of 18IM, compared with REF cells. Pathways involved in oxidative phosphorylation, ubiquinone (Coenzyme Q 10) biosynthesis, fatty acid elongation in mitochondria, PI3K/AKT signaling, a characteristic of rapidly proliferating cells, were upregulated in 18IM. Genes involved in the transcription/translation machinery and redox reactions, like elongation factors, ATP synthases, NADH dehydrogenases, mitogen activated kinases were upregulated as well. 18IM cells produced more pyruvate, indicating enhanced ATP synthesis. The expression of Oct4, Sox2, and Nanog that can contribute to the experimental induction of pluripotency in primary fibroblasts was also elevated, in contrast to Klf4 and C-myc that were downregulated. Subsequently, three new immortalized cell lines were produced by S18-2 overexpression in order to check the representativeness of 18IM. All of them showed anchorage-independent growth pattern. Two of three clones lost vimentin and smooth muscle actin, and expressed Sox2 and Oct4. We suggest that S18-2 is involved in the developmental regulation.
我们最近发现，通过过度表达人线粒体核糖体蛋白 MRPS18-2（S18-2）可以使原代大鼠胚胎成纤维细胞（REF）永生化。衍生的细胞系，命名为 18IM，表达胚胎干细胞标志物 SSEA-1 和 Sox2。接种到严重联合免疫缺陷小鼠中后，18IM 细胞分化为表达泛角蛋白。它们没有致瘤性。在这里，我们报告了 18IM 与 REF 细胞的基因谱比较。涉及氧化磷酸化、泛醌（辅酶 Q10）生物合成、线粒体脂肪酸延长、PI3K/AKT 信号通路的途径，这些都是快速增殖细胞的特征，在 18IM 中上调。参与转录/翻译机制和氧化还原反应的基因，如延伸因子、ATP 合酶、NADH 脱氢酶、有丝分裂原激活激酶等也上调。18IM 细胞产生更多的丙酮酸，表明增强了 ATP 合成。有助于原代成纤维细胞实验诱导多能性的 Oct4、Sox2 和 Nanog 的表达也升高，而 Klf4 和 C-myc 的表达则下调。随后，通过 S18-2 的过表达产生了三个新的永生化细胞系，以检查 18IM 的代表性。它们都表现出非锚定依赖性生长模式。三个克隆中的两个失去了波形蛋白和平滑肌肌动蛋白，表达了 Sox2 和 Oct4。我们认为 S18-2 参与了发育调控。
Zotero 插件
