Heterogeneity among early quail neural crest cells.

In vitro analysis has shown that early migratory quail neural crest cells from the trunk region give rise to 3 types of clonal progeny: clones consisting entirely of melanocytes; clones containing both melanocytes and adrenergic neurons; and clones containing adrenergic neurons as the only differentiated phenotype. These 3 types of clonal progeny could either be the products of distinct subpopulations of progenitor cells or the descendants of one population of pluripotent progenitor cells which, for some reason, often express only one differentiative option. To distinguish between these two possibilities, we probed the plasma membranes of early migratory quail neural crest cells in sparse secondary cultures with the fluorescent dye, merocyanine 540. Progenitors of melanocytes were less sensitive to merocyanine 540-mediated photosensitization than cells giving rise to adrenergic neurons or mixed progeny. Minor differences in the response to merocyanine 540-mediated photosensitization were found between the progenitors of adrenergic neurons and mixed progeny. These results demonstrate that early migratory neural crest cells from the trunk region are a heterogeneous population and that the different types of clonal progeny are the descendants of distinct subpopulations of progenitor cells.