Department of Biosciences and Nutrition, Karolinska Institutet, Hälsovägen 9, 141 57, Huddinge, Sweden.
Competence Centre on Health Technologies, Tartu, Estonia.
Mol Neurobiol. 2020 Jul;57(7):2944-2958. doi: 10.1007/s12035-020-01905-6. Epub 2020 May 22.
Developmental dyslexia (DD) is a neurodevelopmental condition with complex genetic mechanisms. A number of candidate genes have been identified, some of which are linked to neuronal development and migration and to ciliary functions. However, expression and regulation of these genes in human brain development and neuronal differentiation remain uncharted. Here, we used human long-term self-renewing neuroepithelial stem (lt-NES, here termed NES) cells derived from human induced pluripotent stem cells to study neuronal differentiation in vitro. We characterized gene expression changes during differentiation by using RNA sequencing and validated dynamics for selected genes by qRT-PCR. Interestingly, we found that genes related to cilia were significantly enriched among upregulated genes during differentiation, including genes linked to ciliopathies with neurodevelopmental phenotypes. We confirmed the presence of primary cilia throughout neuronal differentiation. Focusing on dyslexia candidate genes, 33 out of 50 DD candidate genes were detected in NES cells by RNA sequencing, and seven candidate genes were upregulated during differentiation to neurons, including DYX1C1 (DNAAF4), a highly replicated DD candidate gene. Our results suggest a role of ciliary genes in differentiating neuronal cells and show that NES cells provide a relevant human neuronal model to study ciliary and DD candidate genes.
发展性阅读障碍(DD)是一种具有复杂遗传机制的神经发育疾病。已经确定了一些候选基因,其中一些与神经元发育和迁移以及纤毛功能有关。然而,这些基因在人类大脑发育和神经元分化中的表达和调控仍未被探索。在这里,我们使用源自人诱导多能干细胞的人长期自我更新神经上皮干细胞(lt-NES,这里称为 NES)细胞来研究体外神经元分化。我们通过 RNA 测序来描述分化过程中的基因表达变化,并通过 qRT-PCR 对选定基因的动力学进行验证。有趣的是,我们发现与纤毛相关的基因在分化过程中显著富集上调基因,包括与具有神经发育表型的纤毛病相关的基因。我们确认了神经元分化过程中初级纤毛的存在。关注阅读障碍候选基因,通过 RNA 测序在 NES 细胞中检测到 50 个 DD 候选基因中的 33 个,并且在向神经元分化过程中上调了 7 个候选基因,包括 DYX1C1(DNAAF4),这是一个高度复制的 DD 候选基因。我们的结果表明纤毛基因在分化神经元细胞中起作用,并表明 NES 细胞提供了一个相关的人类神经元模型,用于研究纤毛和 DD 候选基因。