Fig. 8

puma promotes normal numbers of cells expressing markers of pigment cell lineages. All images are side views of whole-mount larvae during middle stages of pigment pattern metamorphosis with anterior to the left. (A, C, E, G) Wild-type larvae. (B, D, F, H) puma mutant larvae. (A–D) puma mutants exhibit fewer kit⁺ presumptive melanoblasts and melanophores as compared with wild-type. (A, C) In wild-type larvae, staining for kit transcripts is evident in cell peripheries, and unmelanized kit⁺ presumptive melanoblasts are scattered over the flank (C, arrow). (B, D) In puma mutant larvae, kit staining is detectable in melanophores (B, arrow), but unmelanized kit⁺ are dramatically reduced in number. (E, F) puma mutants exhibit fewer ednrb1⁺ pigment cell precursors. (E) In wild-type larvae, ednrb1⁺ cells are widely scattered over the flank, and these cells may represent precursors to melanophores, xanthophores, or iridophores; ednrb1 staining is typically patchy and cell boundaries are not easily detectable (arrow; Parichy et al., 2000b). (F) In puma mutants, fewer ednrb1⁺ cells are detectable during early stages of pigment pattern metamorphosis (arrow), though these cells are recovered during later stages concomitant with the recovery of xanthophores. (G, H) puma mutants exhibit marginally fewer fms⁺ presumptive xanthophore precursors. (G) In wild-type larvae, numerous fms⁺ cells are present both in developing interstripe regions and, to a lesser extent, within developing melanophore stripes (also see Parichy and Turner, 2003b). (H) puma mutants exhibit a mild deficit of fms⁺ cells, consistent with the reduced xanthophore population, as compared with wild-type larvae. By later stages of pigment pattern metamorphosis, puma mutants do not exhibit detectably fewer fms⁺ cells compared with wild-type larvae (data not shown). Scale bar, 40 μm.