ABSTRACT
As seen in previous chapters, the location along the A/P and D/V axes determines which extrinsic signals are available to a particular group of cells at any given stage of development. Further, as cells migrate away from the ventricular surface to reach a new destination, other signals are encountered. Thus, newly formed CNS precursor cells are exposed to a variety of spatially and temporally regulated signals. Similarly, neurons and glia of the peripheral nervous system (PNS) that originate in the neural crest are influenced by numerous spatially and temporally regulated signals that regulate gene expression patterns and final cell fate.
