Roussel-Gervais Audrey, Sgroi Stéphanie, Cambet Yves, Lemeille Sylvain, Seredenina Tamara, Krause Karl-Heinz, Jaquet Vincent
Department of Pathology and Immunology, Faculty of Medicine, University of Geneva, Geneva, Switzerland.
READS Unit, Faculty of Medicine, University of Geneva, Geneva, Switzerland.
Front Cell Neurosci. 2023 Dec 14;17:1289966. doi: 10.3389/fncel.2023.1289966. eCollection 2023.
The tropomyosin receptor kinase B (TrkB) is encoded by the gene. It belongs to the family of transmembrane tyrosine kinases, which have key roles in the development and maintenance of the nervous system. Brain-derived neurotrophic factor (BDNF) and the neurotrophins NT3 and NT4/5 have high affinity for TrkB. Dysregulation of TrkB is associated to a large spectrum of diseases including neurodegeneration, psychiatric diseases and some cancers. The function of TrkB and its role in neural development have mainly been decrypted using transgenic mouse models, pharmacological modulators and human neuronal cell lines overexpressing . In this study, we identified high expression and robust activity of TrkB in ReNcell VM, an immortalized human neural progenitor stem cell line and generated -deficient () ReNcell VM using the CRISPR/Cas9 gene editing technology. Global transcriptomic analysis revealed major changes in expression of specific genes responsible for neurogenesis, neuronal development and glial differentiation. In particular, key neurogenic transcription factors were massively down-regulated in cells, while early glial progenitor markers were enriched in cells compared to . This indicates a previously undescribed inhibitory role of TrkB on glial differentiation in addition to its well-described pro-neurogenesis role. Altogether, we have generated for the first time a human neural cell line with a loss-of-function mutation of , which represents a reproducible and readily available cell culture system to study the role of TrkB during human neural differentiation, analyze the role of TrkB isoforms as well as validate TrkB antibodies and pharmacological agents targeting the TrkB pathway.
原肌球蛋白受体激酶B（TrkB）由该基因编码。它属于跨膜酪氨酸激酶家族，在神经系统的发育和维持中起关键作用。脑源性神经营养因子（BDNF）以及神经营养因子NT3和NT4/5对TrkB具有高亲和力。TrkB的失调与多种疾病相关，包括神经退行性疾病、精神疾病和一些癌症。TrkB的功能及其在神经发育中的作用主要通过转基因小鼠模型、药理学调节剂以及过表达的人类神经元细胞系来解密。在本研究中，我们在永生化的人类神经祖干细胞系ReNcell VM中鉴定出TrkB的高表达和强大活性，并使用CRISPR/Cas9基因编辑技术生成了TrkB缺陷型（TrkB-/-）ReNcell VM。全转录组分析揭示了负责神经发生、神经元发育和胶质细胞分化的特定基因表达的主要变化。特别是，关键的神经源性转录因子在TrkB-/-细胞中大量下调，而与TrkB+/+细胞相比，早期胶质祖细胞标志物在TrkB-/-细胞中富集。这表明TrkB除了其已被充分描述的促进神经发生作用外，对胶质细胞分化还有先前未描述的抑制作用。总之，我们首次生成了具有TrkB功能丧失突变的人类神经细胞系，这代表了一种可重复且易于获得的细胞培养系统，用于研究TrkB在人类神经分化过程中的作用、分析TrkB异构体的作用以及验证靶向TrkB途径的抗体和药物制剂。
