New roles for PDGF and CNTF in controlling the timing of glial cell differentiation in the optic nerve

A satisfactory explanation of neural development (or indeed, of any developing tissue) must account not only for the numbers and types of cell that differentiate, but also for the schedule on which they appear. A series of studies over the past several years by Raft, Noble, Miller and their collaborators has established the perinatal optic nerve as a relatively simple system in which the development of two glial cell types can be effectively investigated.