Fig. 1

Larval-to-adult transformation of the zebrafish pigment pattern. (A) Early larval pigment pattern. Shown is an individual at 14 dpf, at the onset of pigment pattern metamorphosis. Established during embryogenesis, the early larval pattern of melanophore stripes persists through the onset of metamorphosis. On the trunk, this pattern consists of an early larval dorsal melanophore stripe (ELD), an early larval lateral melanophore stripe (ELL) along the horizontal myoseptum, and an early larval ventral melanophore stripe (ELV). Below the plane of focus, melanophores also can be seen along the dorsal neural tube and the dorsal aorta (small arrows). At the onset of pigment pattern metamorphosis, a few xanthophores and iridophores (large arrow) are apparent immediately ventral to the early larval lateral melanophore stripe. (B) An early adult/juvenile pigment pattern develops by terminal stages of pigment pattern metamorphosis. Shown is an individual at 37 dpf. Two adult primary melanophore stripes have developed dorsal (1D) and ventral (1V) to a light interstripe region containing xanthophores and iridophores. The first adult secondary melanophore stripe (2V) has started to form near the base of the anal fin. Dorsally, melanophores and xanthophores are scattered over the myotomes and populate the dorsal scales (S). Arrowheads in (A) and (B) show location of the horizontal myoseptum; note that EL melanophores initially present at this location (A, ELL) are absent by terminal stages of pigment pattern metamorphosis (B). Images are not to the same scale: Scale bars, (A) 150 μm, (B) 500 μm.