Figure 1

Effects of G93A- SOD1 on developing zebrafish MN axons. Zebrafish embryos at the 1-4 cell stage were microinjected with wtSOD1, G93A-SOD1 and/or igf-I RNA after timed mating of adult AB strain zebrafish and underwent IHC with the SV2 antibody at 30 hpf to visualize MN axons. (A) SV2 IHC demonstrates increased branching of motor axons, represented by (*) in embryos injected with G93A-SOD1 (50 ng/μl) RNA, compared to embryos injected with wtSOD1 (50 ng/μl) RNA. 20x magnification confocal images; scale bar equals 50 μm. (B) Measurement of axon length in embryos injected with 0-100 ng/μl G93A-SOD1 RNA reveals a dose-dependent decrease in MN axon length; * P < 0.001 compared to UIC. (C) Co-injection of igf-I RNA (I; 200 ng/μl) attenuates the effects of G93A-SOD1 (G; 50 ng/μl) on axon length. No significant effects of wtSOD1 (W; 50 ng/μl) are observed, regardless of IGF-I expression. * P < 0.001 compared to UIC.