Figure 4

Met is required for initiation of dorsal OPC migration. (A) Diagram of met^uva38 mutant created using CRISPR/Cas9 mutagenesis with gRNA target sequence (yellow) and PAM site (blue) resulting in a 16 base pair insertion, which causes a frameshift mutation and early stop codon (asterisk). (B) Diagram of wildtype Met protein and Met mutant polypeptide sequences. (C) Images taken from 18 h time-lapse imaging of 55 hpf olig2:egfp met^+/+, and met^uva38/uva38 zebrafish larvae. Yellow open arrowheads denote dorsally migrating OPCs. Yellow dashed line denotes ventral edge of spinal cord. (D–F) Quantifications taken from time-lapse movies of 55 hpf olig2:egfp met^+/+ (n = 8), met^+/uva38 (n = 8), and met^uva38/uva38 (n = 6) zebrafish larvae. Mean with SEM. Statistical test: one-way ANOVA with Tukey’s Multiple Comparison Test was used for D–F. Scale bar, 20 μm.