Li Yuanyuan, Wang Ran, Qiao Nan, Peng Guangdun, Zhang Ke, Tang Ke, Han Jing-Dong J, Jing Naihe
From the State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology and.
Chinese Academy of Sciences Key Laboratory of Computational Biology, Chinese Academy of Sciences-Max Planck Partner Institute for Computational Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031.
J Biol Chem. 2017 Dec 1;292(48):19590-19604. doi: 10.1074/jbc.M117.796383. Epub 2017 Sep 26.
Proper neural commitment is essential for ensuring the appropriate development of the human brain and for preventing neurodevelopmental diseases such as autism spectrum disorders, schizophrenia, and intellectual disorders. However, the molecular mechanisms underlying the neural commitment in humans remain elusive. Here, we report the establishment of a neural differentiation system based on human embryonic stem cells (hESCs) and on comprehensive RNA sequencing analysis of transcriptome dynamics during early hESC differentiation. Using weighted gene co-expression network analysis, we reveal that the hESC neurodevelopmental trajectory has five stages: pluripotency (day 0); differentiation initiation (days 2, 4, and 6); neural commitment (days 8-10); neural progenitor cell proliferation (days 12, 14, and 16); and neuronal differentiation (days 18, 20, and 22). These stages were characterized by unique module genes, which may recapitulate the early human cortical development. Moreover, a comparison of our RNA-sequencing data with several other transcriptome profiling datasets from mice and humans indicated that Module 3 associated with the day 8-10 stage is a critical window of fate switch from the pluripotency to the neural lineage. Interestingly, at this stage, no key extrinsic signals were activated. In contrast, using CRISPR/Cas9-mediated gene knockouts, we also found that intrinsic hub transcription factors, including the schizophrenia-associated gene and septo-optic dysplasia-related gene, are required to program hESC neural determination. Our results improve the understanding of the mechanism of neural commitment in the human brain and may help elucidate the etiology of human mental disorders and advance therapies for managing these conditions.
适当的神经定向对于确保人类大脑的正常发育以及预防神经发育疾病（如自闭症谱系障碍、精神分裂症和智力障碍）至关重要。然而，人类神经定向的分子机制仍然难以捉摸。在这里，我们报告了基于人类胚胎干细胞（hESC）建立的神经分化系统，以及对hESC早期分化过程中转录组动态的全面RNA测序分析。使用加权基因共表达网络分析，我们揭示hESC神经发育轨迹有五个阶段：多能性（第0天）；分化起始（第2、4和6天）；神经定向（第8 - 10天）；神经祖细胞增殖（第12、14和16天）；以及神经元分化（第18、20和22天）。这些阶段由独特的模块基因表征，这可能概括了人类早期皮质发育。此外，将我们的RNA测序数据与来自小鼠和人类的其他几个转录组分析数据集进行比较表明，与第8 - 10天阶段相关的模块3是从多能性向神经谱系命运转换的关键窗口。有趣的是，在这个阶段，没有关键的外在信号被激活。相反，使用CRISPR/Cas9介导的基因敲除，我们还发现包括精神分裂症相关基因和视隔发育不良相关基因在内的内在枢纽转录因子是hESC神经决定编程所必需的。我们的结果增进了对人类大脑神经定向机制的理解，并可能有助于阐明人类精神障碍的病因，推进这些疾病的治疗方法。
