Figure 1: Crb3 negatively regulates myelin sheath elongation.

(a) Crb3 immunostaining (red) localizes as discrete lines typical of microvilli at the extremities of mSC (GFP, green). (b) Crb3 (red) partially colocalizes with microvilli marker moesin (green) in a typical band pattern. (c) Confocal images Z axis projection of Crb3 immunostaining (red) reveals a typical microvilli ring around axonal node marker Ankyrin G (green). (d) Representative mSCs infected with Crb3 (Crb3 sh, DsRed2) or control shRNAs (Cont sh, GFP) lentiviruses. (e) Lengths versus diameters of mSCs infected with Crb3 (black square, n=83, slope line 2) or control (white circle, n=60, slope line 1) shRNA viruses. Two independent shRNAs against Crb3 yielded similar results (results from only one is shown). Three animals for control and Crb3 sh virus. (f) Average length (left) and diameter (right) of mSCs described in e. (g) mSC infected with Crb3 shRNA virus (Crb3sh, DsRed2) is longer than the next non-infected mSC (NI) on the same axon. Nodal regions (arrows) are visualized using Kv1.2 immunostaining (green) and nuclei using DAPI (blue). Statistical two-tailed Student’s t-tests: ***P<0.001; NS, P>0.05 not significant. Scale bars, 100 μm (a,d,g), 5 μm (b,c). Error bars show s.e.m.