The pale mutation in Bombina orientalis: Effects on melanophores and xanthophores

The pale defect in Bombina orientalis has been examined both biochemically (for pigment defects) and ultrastructurally (for cellular defects). Both xanthophores and melanophores (but not iridophores) are affected by this gene in a manner suggesting that the pigmentation process is inhibited prior to the formation of mature pigment organelles. Of interest is the presence of multivesicular structures in the organelles of mutant xanthophores and melanophores. It is proposed that this mutation acts at the level of a “primordial organelle” common to both pigment cell types.