Fig. 2 nrg1 type II is required for normal myelin sheath number in the spinal cord at 5 dpf
Myelin sheaths analyzed using transient transgenic expression of mbp:GFP construct to scatter label oligodendrocytes in the dorsal spinal cord at 5 dpf.
(A) Myelin sheath number is significantly reduced in nrg1 EGF and type II mutants, similar to the reduction seen in erbb2 mutants. Scale bar represents 25 μm.
(B and C) Total sheath length per oligodendrocyte (OL) is significantly reduced in nrg1 EGF and nrg1 type II mutants.
(D) A similar reduction in total sheath length is observed in erbb2 mutants. (B’–D’) This reduction in total sheath length is driven by a reduction in sheath number per oligodendrocyte, rather than a reduction in sheath length. Animals were genotyped after imaging. Error bars represent mean ± SD. A t test was used to assess significance, and p values were adjusted for multiple comparisons. Each point represents one OL; ≥ 12 OLs per category from ≥4 animals per category; one representative experiment shown from three replicates.