Fig. 7. Summary of context-dependent fates: fate decisions are dependent on levels of Sox10, presence of soluble extracellular factors such as NRG1 and short-range cell-cell interactions. Summary of the observed phenotypes. Postmigratory neural crest cells isolated from wild-type DRG produce predominantly glia-containing clones in differentiation medium and in differentiation medium supplemented with NRG1, irrespective of their cellular context. By contrast, single Sox10 heterozygous cells undergo a fate switch and produce only non-neural cells at the expense of the glial fate. Moreover, in high density cultures that allow short range cell-cell interactions to occur, Sox10 heterozygous cells undergo limited gliogenesis while neurogenesis is a prominent fate. The promotion of gliogenesis in Sox10 heterozygous cells is dependent on the synergistic activities of short range cell-cell interactions and the presence of NRG1. In summary, extracellular signals influencing cell fate decisions are differentially interpreted by postmigratory neural crest cells, depending on the cellular context and the level of Sox10.