We used the following primary antibodies: mouse anti–Gpr56-H11 (1:1,000; Jeong et al., 2012 (link)), rabbit anti–Ki67 (1:400; Abcam; Mogha et al., 2013 (link)), rabbit anti–TUJ1 (1:1,000; Covance; Mogha et al., 2013 (link)), rat anti–MBP (1:10; AbD Serotec; Mogha et al., 2013 (link)), and mouse anti–pan sodium channel (IgG1, 1:400; Sigma-Aldrich; Saito et al., 2003 (link)). Fluorescently conjugated secondary antibodies were applied at a concentration of 1:1,000 (Invitrogen). Rhodamine-phalloidin (1:100; Invitrogen; Terada et al., 2012 (link)) was used for staining of Schmidt-Lanterman incisures.