Fig. 7

Cell autonomous activation of FGFRs on pMN progenitor cells is required to maintain Olig2 expression at the time of OPC specification. a-b Immunodetection of Olig2 (red in a and b, a', b') and Nkx2.2 (blue in a and b, a'', b'') on transverse sections of explants electroporated with the control vector (green in a) or with the dnFGFR vector (green in b) and cultivated for 2 days. Note the reduced number of Olig2/Nkx2.2-positive cells generated in the dnFGFR electroporated side of explant in (b). Note also diminished level of Olig2 expression in progenitor cells electroporated with the dnFGFR vector (arrows in b) compared to those electroporated with the control vector (arrows in a). c Quantification of GFP-positive and GFP/Olig2-positive cells in the p* domain (brackets in a, a', a", b, b', b") in control (n = 3) and dnFGFR electroporated (n = 4) explants. Results are presented as mean number of cells ± sem (* p ≤ 0.03). Scale bars = 50 μm