Figure 1. TACE/ADAM17 is expressed by OL lineage cells during SCWM development. A, B, WB analysis and quantification of TACE expression from SCWM protein extracts obtained at P8–P90. C–E, Characterization by immunofluorescence analysis of TACE expression in OL lineage cells during SCWM development. Immunofluorescence with anti-TACE and CC1 antibodies at P15 in the SCWM of CNP-EGFP (C) and NG2-dsRed (D, E) mice. OPs are characterized by NG2 expression and low CNP-EGFP expression levels and pre-OLs by CC1 expression and high CNP-EGFP levels (C, D). TACE is expressed by both OP cells (CNP-EGFPlow CC1neg, C1; NG2-dsRedhigh, D1, E1a, E1b) and premyelinating OLs (CNP-EGFPhigh CC1+, C2; NG2-dsRedlow, D2, E2). D3, Represents a mature OL, characterized CC1 expression, and NG2-dsRedneg. F, Characterization of TACE expression during OL development in vitro. NG2+ cells were FAC-sorted at P8 from the SCWM. F, Top, Immunofluorescence analysis with anti-TACE antibodies shows TACE expression in OPs (PDGFRα+). F, Bottom, FAC-sorted NG2+ cells were also maintained in culture under differentiation conditions for 4 d to allow OL differentiation. This analysis showed that TACE is also expressed in cells undergoing OL differentiation (CNP+ cells). G, A typical FACS plot diagram of CNP-EGFP+ cells isolated from SCWM of the CNP-EGFP mouse at P4. H, I, RT-PCR analysis and quantification of TACE from CNP-EGFPlow (OPs) and CNP-EGFPhigh (OLs) FAC-sorted cells. Data are shown as mean ± SEM, n = 5 brains for each time point and three independent experiments. Scale bars: C–E, 10 μm; F, 5 μm.