Complete loss of the pigment pattern in double mutants of nac, pfe, and shd with leotK3.
Mutants lacking one pigment cell type, nac (A and A′), pfe (C and C′), and shd (E and E′), only form remnants of the pigmentation pattern. In nac mutants fields of dense iridophores covered with compact xanthophores (corresponding to light stripes) and loose iridophores (corresponding to dark stripes) are discernible as patches (A′). In homozygous double mutants leotK3;nac (B) the regions of dense iridophores covered by compact xanthophores expand at the expense of blue iridophore areas. In pfe mutants (C) in the absence of xanthophores the melanophores form patches in the regions around the first light stripe but are increasingly more disorganized at some distance to it (C′). In double mutants of pfe with homozygous leotK3 melanophores are distributed almost evenly as individual cells over the flank of the fish (D). In shd mutants (E), where no iridophores are present, melanophores and xanthophores only partly form the first light and dark stripes (E′). In double homozygous double mutants leotK3;shd this residual pattern is lost and only very few individual melanophores are left on the flank of the fish (F).