MRC Centre for Regenerative Medicine, University of Edinburgh, Edinburgh BioQuarter, 5 Little France Drive, Edinburgh EH16 4UU, Scotland, UK.
Department of Experimental Medical Science, Developmental and Regenerative Neurobiology, Wallenberg Neuroscience Center and Lund Stem Cell Center, Lund University, 22184 Lund, Sweden.
Cell Stem Cell. 2017 Dec 7;21(6):791-805.e9. doi: 10.1016/j.stem.2017.10.013. Epub 2017 Nov 22.
Reprogramming of cellular identity using exogenous expression of transcription factors (TFs) is a powerful and exciting tool for tissue engineering, disease modeling, and regenerative medicine. However, generation of desired cell types using this approach is often plagued by inefficiency, slow conversion, and an inability to produce mature functional cells. Here, we show that expression of constitutively active SMAD2/3 significantly improves the efficiency of induced pluripotent stem cell (iPSC) generation by the Yamanaka factors. Mechanistically, SMAD3 interacts with reprogramming factors and co-activators and co-occupies OCT4 target loci during reprogramming. Unexpectedly, active SMAD2/3 also markedly enhances three other TF-mediated direct reprogramming conversions, from B cells to macrophages, myoblasts to adipocytes, and human fibroblasts to neurons, highlighting broad and general roles for SMAD2/3 as cell-reprogramming potentiators. Our results suggest that co-expression of active SMAD2/3 could enhance multiple types of TF-based cell identity conversion and therefore be a powerful tool for cellular engineering.
使用转录因子 (TFs) 的外源表达来重新编程细胞身份是组织工程、疾病建模和再生医学的强大而令人兴奋的工具。然而，使用这种方法产生所需的细胞类型通常受到效率低、转化缓慢和无法产生成熟功能细胞的困扰。在这里，我们表明，组成型激活的 SMAD2/3 的表达显著提高了 Yamanaka 因子诱导多能干细胞 (iPSC) 生成的效率。在机制上，SMAD3 与重编程因子和共激活因子相互作用，并在重编程过程中共同占据 OCT4 靶基因座。出乎意料的是，活性 SMAD2/3 还显著增强了另外三种 TF 介导的直接重编程转化，从 B 细胞到巨噬细胞，从成肌细胞到脂肪细胞，以及从人成纤维细胞到神经元，突出了 SMAD2/3 作为细胞重编程增强剂的广泛和普遍作用。我们的结果表明，共表达活性 SMAD2/3 可以增强多种基于 TF 的细胞身份转化，因此是细胞工程的有力工具。
