Reelin in the Years: Controlling Neuronal Migration and Maturation in the Mammalian Brain

Figure 1

Schematic representation of the multiple activities of Reelin in the developing and adult forebrain. Blue octagons represent secreted Reelin molecules, and red ovals represent the cell bodies of principal forebrain neurons (N). During embryonic development, Reelin is mostly localized to the marginal zone (MZ) and directs radial migration by affecting multiple steps, such as radial orientation (1), attachment of the leading edge to the MZ (2), and somal translocation (3). During postnatal development, Reelin becomes expressed throughout cortical forebrain structures (CX), where it promotes mainly the growth of apical dendrites and spine formation. In the adult brain, Reelin modulates synaptic function and plasticity.