Figure 5.

Figure 5.

Confocal imaging of myelin sheath structures of zebrafish exposed to domoic acid (DomA) at different developmental days (A) Tg(mbp:EGFP-CAAX) fish were used to visualize labeled myelin sheaths. (B) Representative images of fish exposed to DomA (0.13–0.14 ng) during discrete periods in early development [1–4 d postfertilization (dpf)], then imaged at 5 dpf using confocal microscopy. Arrows indicate the unusual circular membrane profiles. (C) Stacked bar plots show the distribution of the different myelin phenotypes when fish were exposed to DomA at discrete developmental times. Multiple trials were combined to calculate the percentage distribution per phenotype observed. (D) Representative confocal microscopy images of different myelin phenotypes that were observed. Each fish was blindly classified and assigned a category based on the severity of the myelin deficit observed. The scoring was as described in detail in Figure S2. Briefly, the classification was as follows: (0) normal phenotype, (1) myelin sheaths present but disorganized, (2) myelin with noticeable deficits, (3) myelin gaps in ventral spinal cord, and (4) myelin sheaths lacking in ventral spinal cord. Scale bar: 50μm (Figure 5B) and 100μm (Figure 5D). Table S20 includes the number of trials represented along with the associated numbers of fish per trial.