Fig. 2From: The impact of RASopathy-associated mutations on CNS development in mice and humansEffect of RAS signaling components on neural stem cell differentiation. Neural stem cells are able to generate progeny cells that terminally differentiate into neurons, oligodendrocytes, and astrocytes. a NF1 inactivation led to decreased neurogenesis in neonatal and adult mouse brains [85]. PTPN11 positively regulates neurogenesis at the expense of gliogenesis [96]. b NF1 negatively regulates gliogenesis, thus NF1 inactivation increases the number of glial progenitor cells and gliogenesis [78, 79, 85, 89, 159, 160]. PTPN11 suppresses gliogenesis by directly interacting with the JAK-STAT pathway, which promotes gliogenesis [92, 96]. c Hyperactivation of RAF1 induces the increase of glial lineage populations, including oligodendrocyte progenitor cells and astrocytes [107]. MEK is required for gliogenesis, and the hyperfunction of MEK1 leads to increase in glial populations [108, 109]. d BRAF and RAF1 positively regulate neuronal differentiation, and the disruption of BRAF or RAF1 impairs the ability of progenitor cells to differentiate into mature neurons in mouse brain [102, 105]. In consistent, iPSC containing hyperactivated BRAF mutant showed early maturation of neurons [190]. e Oligodendroglial lineage potential is restricted by NF1 in the adult hippocampus, and inactivation of NF1 allows the adult hippocampus to generate oligodendrocytes [85]. f BRAF is required for oligodendrocyte maturation and myelination during postnatal development [103]. g Hyperactivated HRAS leads to an acceleration of astroglial maturation [206, 211]. Blue and red arrows indicate positive and negative regulation, respectively.Back to article page