Fig. 3

Fig. 3

Dync1h1 deficient zebrafish have a deficit of oligodendrocytes, each of which has fewer myelin sheaths. A,B: Immunohistochemistry to detect Sox10 (red) in combination with olig2:EGFP (green) marks oligodendrocyte lineage cells in 4 dpf wild-type and dync1h1^vu76 mutant larvae. Panels show representative images of transverse sections through the trunk spinal cord, with dorsal up. Anti-acetylated Tubulin staining (blue) marks axons. C: Mutant larvae have approximately 50% the normal number of oligodendrocyte lineage cells. D,E: Data, collected from time-lapse movies, showing fewer dorsally migrating OPCs and fewer OPC divisions in dync1h1 MO-injected larvae than in wild-type. F,G: Representative images of single, sox10:EGFP-CaaX⁺ oligodendrocytes in 6 dpf control (F) and dync1h1^vu76 mutant (G) larvae. Asterisks mark cell bodies and arrows mark ends of single myelin sheaths. H: Quantification revealed fewer sheaths in dync1h1^vu76 mutant larvae than in control. I: Graph showing that average myelin sheath length is slightly longer in dync1h1^vu76 mutant larvae than in wild-type. However, the statistical significance of the difference is weak (P = 0.0414). J: Box-and-whisker plot revealed that both the minimum (min) and maximum (max) lengths of sheaths in dync1h1^vu76 mutant larvae were slightly more variable than in control larvae. However, the differences between the average maximum and minimum lengths were not significant (ns). K: Graph showing the average total myelin sheath lengths of individual oligodendrocytes. Error bars represent ± SEM. For panels H–K, wild-type data were collected from 28 cells in 11 larvae. Mutant data were collected from 15 cells in 9 larvae. Statistical significance was determined by Student′s t-test for panels C–E and by nonparametric two tailed Mann-Whitney t-test for panels H–K. ***P < 0.0001; **P < 0.001; *P < 0.05.