Generation of Reelin-Positive Marginal Zone Cells from the Caudomedial Wall of Telencephalic Vesicles

• DOI: 10.1523/jneurosci.4671-03.2004
• Publication Date: 2004-03-03T18:02:46Z
• Authors: Keiko Takiguchi-H...; Mariko Sekiguchi; Shizuko Ashigaki; Masako Takamatsu; Hiroshi Hasegawa; Rika Suzuki-Migis...; Minesuke Yokoyama; Shigetada Nakanishi; Yasuto Tanabe
• Keywords: Neurons; 0301 basic medicine; Extracellular Matrix Proteins; Mice, Inbred ICR; Cell Adhesion Molecules, Neuronal; Green Fluorescent Proteins; Gestational Age; Mice, Transgenic; Neocortex; Nerve Tissue Proteins; Antigens, Differentiation; DNA-Binding Proteins; Mice, Inbred C57BL; Luminescent Proteins; Mice; 03 medical and health sciences; Electroporation; Cell Movement; Genes, Reporter; Animals; Genes, Tumor Suppressor; Cells, Cultured

An early and fundamental step of the laminar organization of developing neocortex is controlled by the developmental programs that critically depend on the activities of reelin-positive cells in the marginal zone. However, the ontogeny of reelin-positive cells remained elusive. To gain insights into the spatial and temporal regulation of reelin-positive marginal zone cell development, we used a transgenic mouse line in which we defined the green fluorescent protein (GFP) transgene as a novel reliable molecular marker of reelin-positive marginal zone cells from the early stages of their development. We further usedexo uteroelectroporation-mediated gene transfer that allows us to mark progenitor cells and monitor the descendants in the telencephalonin vivo. We show here the generation of reelin-positive marginal zone cells from the caudomedial wall of telencephalic vesicles, including the cortical hem, where the prominent expression of GFP is initially detected. These neurons tangentially migrate at the cortical marginal zone and are distributed throughout the entire neocortex in a caudomedial-high to rostrolateral-low gradient during the dynamic developmental period of corticogenesis. Therefore, our findings on reelin-positive marginal zone cells, in addition to the cortical interneurons, add to the emerging view that the neocortex consists of neuronal subtypes that originate from a focal source extrinsic to the neocortex, migrate tangentially into the neocortex, and thereby underlie neural organization of the neocortex.