Department of Biology, Huck Institutes of Life Sciences, Pennsylvania State University, University Park, Pennsylvania, USA.
GHM Institute of CNS Regeneration, Jinan University, Guangzhou, China.
Dev Neurobiol. 2022 Jul;82(5):375-391. doi: 10.1002/dneu.22882. Epub 2022 May 23.
Ectopic expression of a single neural transcription factor NeuroD1 can reprogram reactive glial cells into functional neurons both in vitro and in vivo, but the underlying mechanisms are not well understood yet. Here, we used RNA-sequencing technology to capture the transcriptomic changes at different time points during the reprogramming process. We found that following NeuroD1 overexpression, astroglial genes (ACTG1, ALDH1A3, EMP1, CLDN6, SOX21) were significantly downregulated, whereas neuronal genes (DCX, RBFOX3/NeuN, CUX2, RELN, SNAP25) were significantly upregulated. NeuroD family members (NeuroD1/2/6) and signaling pathways (Wnt, MAPK, cAMP) as well as neurotransmitter receptors (acetylcholine, somatostatin, dopamine) were also significantly upregulated. Gene co-expression analysis identified many central genes among the NeuroD1-interacting network, including CABP7, KIAA1456, SSTR2, GADD45G, LRRTM2, and INSM1. Compared to chemical conversion, we found that NeuroD1 acted as a strong driving force and triggered fast transcriptomic changes during astrocyte-to-neuron conversion process. Together, this study reveals many important downstream targets of NeuroD1 such as HES6, BHLHE22, INSM1, CHRNA1/3, CABP7, and SSTR2, which may play critical roles during the transcriptomic landscape shift from a glial profile to a neuronal profile.
单一神经转录因子 NeuroD1 的异位表达可以在体外和体内将反应性神经胶质细胞重新编程为功能性神经元，但其中的机制尚不清楚。在这里，我们使用 RNA 测序技术在重编程过程中的不同时间点捕获转录组变化。我们发现，NeuroD1 过表达后，星形胶质细胞基因（ACTG1、ALDH1A3、EMP1、CLDN6、SOX21）显著下调，而神经元基因（DCX、RBFOX3/NeuN、CUX2、REELN、SNAP25）显著上调。NeuroD 家族成员（NeuroD1/2/6）和信号通路（Wnt、MAPK、cAMP）以及神经递质受体（乙酰胆碱、生长抑素、多巴胺）也显著上调。基因共表达分析确定了 NeuroD1 相互作用网络中的许多核心基因，包括 CABP7、KIAA1456、SSTR2、GADD45G、LRRTM2 和 INSM1。与化学转化相比，我们发现 NeuroD1 作为一种强大的驱动力，在星形胶质细胞向神经元转化过程中引发快速的转录组变化。总的来说，这项研究揭示了 NeuroD1 的许多重要下游靶标，如 HES6、BHLHE22、INSM1、CHRNA1/3、CABP7 和 SSTR2，它们在从神经胶质表型到神经元表型的转录组景观转变过程中可能发挥关键作用。
