Shc signaling in differentiating neural progenitor cells.

Previously we found that the availability of ShcA adapter is maximal in neural stem cells but that it is absent in mature neurons. Here we report that ShcC, unlike ShcA, is not present in neural stem/progenitor cells, but is expressed after cessation of their division and becomes selectively enriched in mature neurons. Analyses of its activity in differentiating neural stem/progenitor cells revealed that ShcC positively affects their viability and neuronal maturation via recruitment of the PI3K-Akt-Bad pathway and persistent activation of the MAPK pathway. We suggest that the switch from ShcA to ShcC modifies the responsiveness of neural stem/progenitor cells to extracellular stimuli, generating proliferation (with ShcA) or survival/differentiation (with ShcC).