How does the mammalian neocortex acquire the unique six-layered structure considered to be the structural basis for the remarkable evolution of complex neural circuits? We focus on subplate (SP) neurons that develop and mature too early during cortical development but disappear postnatally to approach this question. Recently, we found that SP neurons play an essential role in radial neuronal migration via direct interaction with young migrating neurons. Moreover, the SP layer is surrounded by a rich extracellular matrix (ECM), suggesting that it may be an important signaling center for mammalian corticogenesis. Functional elucidation of the SP layer should lead to a better understanding of brain development during evolution.
“We are interested in the roles of the subplate later in the development of the cerebral cortex. It suggests that this transient cell population plays a crucial role as a symbolic “control tower” during neocortical formation and also adult cortical function.”