dmbx1a mRNA expression. Whole mounts are shown in lateral views (A, B). A1-A3: WISH transversal cryostat sections of a stage 72 hpf WT. B1-B3: WISH transversal cryostat sections of a stage 72 hpf mibhi904. Abbreviations (as above): cec, cerebellar commissure; Ch, chorda dorsalis; Poc, postoptic commissure; Va, valvula cerebelli. Scale bars: 0.2 mm (A, B), 0.1 mm (A1–A4, B1-B3).