Changes in protein kinase C activities are correlated with the metaplastic transformation of schwann cell precursors of avian embryos into melanocytes

In previous work, we found that the phorbol ester drug 12‐0‐tetradecanoyl phorbol acetate (TPA) reverses the developmental restriction of melanogenesis that occurs early in neural crest development, causing Schwann cell precursors to undergo a metaplastic transformation into melanocytes. In this study, we examine whether these effects of TPA may be mediated by changes in endogenous levels of protein kinase C (PKC) activities. We report that low levels of PKC activity are correlated with this adventitious pigmentation in the crest‐derived cells of dorsal root ganglia both during normal development and following TPA treatment in culture. These results suggest that regulation of endogenous levels of PKC plays a role in developmental decisions that neural crest cells make during early embryogenesis.