The MOE Key Laboratory of Cell Proliferation and Differentiation, College of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China and Department of Cell Biology, School of Basic Medical Sciences, Peking University Stem Cell Research Center, Center for Molecular and Translational Medicine, State Key Laboratory of Natural and Biomimetic Drugs, Peking University Health Science Center, Beijing 100191, China.
Shenzhen Stem Cell Engineering Laboratory, Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen, Guangdong 518055, China.
Cell Stem Cell. 2015 Aug 6;17(2):195-203. doi: 10.1016/j.stem.2015.06.003.
Recently, direct reprogramming between divergent lineages has been achieved by the introduction of regulatory transcription factors. This approach may provide alternative cell resources for drug discovery and regenerative medicine, but applications could be limited by the genetic manipulation involved. Here, we show that mouse fibroblasts can be directly converted into neuronal cells using only a cocktail of small molecules, with a yield of up to >90% being TUJ1-positive after 16 days of induction. After a further maturation stage, these chemically induced neurons (CiNs) possessed neuron-specific expression patterns, generated action potentials, and formed functional synapses. Mechanistically, we found that a BET family bromodomain inhibitor, I-BET151, disrupted the fibroblast-specific program, while the neurogenesis inducer ISX9 was necessary to activate neuron-specific genes. Overall, our findings provide a "proof of principle" for chemically induced direct reprogramming of somatic cell fates across germ layers without genetic manipulation, through disruption of cell-specific programs and induction of an alternative fate.
最近，通过引入调节转录因子，已经实现了不同谱系之间的直接重编程。这种方法可以为药物发现和再生医学提供替代的细胞资源，但由于涉及基因操作，应用可能会受到限制。在这里，我们表明，仅使用小分子鸡尾酒，就可以将小鼠成纤维细胞直接转化为神经元细胞，诱导 16 天后，TUJ1 阳性细胞的产量高达 90%以上。经过进一步的成熟阶段，这些化学诱导的神经元（CiNs）具有神经元特异性的表达模式，产生动作电位，并形成功能性突触。从机制上讲，我们发现 BET 家族溴结构域抑制剂 I-BET151 破坏了成纤维细胞特异性程序，而神经发生诱导剂 ISX9 是激活神经元特异性基因所必需的。总的来说，我们的研究结果为在不进行遗传操作的情况下，通过破坏细胞特异性程序和诱导替代命运，用化学方法跨胚层诱导体细胞命运的直接重编程提供了“原理证明”。
