title: Classic cadherin expressions balance postnatal neuronal positioning and dendrite dynamics to elaborate the specific cytoarchitecture of the mouse cortical area.
abstract: A unique feature of the mammalian cerebral cortex is in its tangential parcellation via anatomical and functional differences. However, the cellular and/or molecular machinery involved in cortical arealization remain largely unknown. Here we map expression profiles of classic cadherins in the postnatal mouse barrel field of the primary somatosensory area (S1BF) and generate a novel bacterial artificial chromosome transgenic (BAC-Tg) mouse line selectively illuminating nuclei of cadherin-6 (Cdh6)-expressing layer IV barrel neurons to confirm that tangential cellular assemblage of S1BF is established by postnatal day 5 (P5). When we electroporate the cadherins expressed in both barrel neurons and thalamo-cortical axon (TCA) terminals limited to the postnatal layer IV neurons, S1BF cytoarchitecture is disorganized with excess elongation of dendrites at P7. Upon delivery of dominant negative molecules for all classic cadherins, tangential cellular positioning and biased dendritic arborization of barrel neurons are significantly altered. These results underscore the value of classic cadherin-mediated sorting among neuronal cell bodies, dendrites and TCA terminals in postnatally elaborating the S1BF-specific tangential cytoarchitecture. Additionally, how the "protocortex" machinery affects classic cadherin expression profiles in the process of cortical arealization is examined and discussed.
authors.affiliation: Department of Biochemistry and Cellular Biology, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Ogawahigashi, 4-1-1, Kodaira, Tokyo 187-8502, Japan; Department of Electrical Engineering and Bioscience, Graduate School of Advanced Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo 169-8555, Japan. Electronic address: segusa@ncnp.go.jp.
authors.forename: Saki F
authors.initials: SF
authors.lastname: Egusa
authors.affiliation: Department of Biochemistry and Cellular Biology, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Ogawahigashi, 4-1-1, Kodaira, Tokyo 187-8502, Japan. Electronic address: yinn3@ncnp.go.jp.
authors.forename: Yukiko U
authors.initials: YU
authors.lastname: Inoue
authors.affiliation: Department of Biochemistry and Cellular Biology, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Ogawahigashi, 4-1-1, Kodaira, Tokyo 187-8502, Japan. Electronic address: asami@ncnp.go.jp.
authors.forename: Junko
authors.initials: J
authors.lastname: Asami
authors.affiliation: Department of Biochemistry and Cellular Biology, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Ogawahigashi, 4-1-1, Kodaira, Tokyo 187-8502, Japan; Division of Morphological Neuroscience, Gifu University Graduate School of Medicine, 1-1 Yanagito, Gifu 501-1194, Japan. Electronic address: y_tera@gifu-u.ac.jp.
authors.forename: Youhei W
authors.initials: YW
authors.lastname: Terakawa
authors.affiliation: Department of Biochemistry and Cellular Biology, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Ogawahigashi, 4-1-1, Kodaira, Tokyo 187-8502, Japan. Electronic address: hoshino@ncnp.go.jp.
authors.forename: Mikio
authors.initials: M
authors.lastname: Hoshino
authors.affiliation: Department of Biochemistry and Cellular Biology, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Ogawahigashi, 4-1-1, Kodaira, Tokyo 187-8502, Japan. Electronic address: tinoue@ncnp.go.jp.
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Inoue
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D015820:Cadherins / Q000235:genetics / Q000378:metabolism*; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000378:metabolism* / Q000648:ultrastructure; D022202:Chromosomes, Artificial, Bacterial / Q000235:genetics; D003712:Dendrites / Q000378:metabolism / Q000648:ultrastructure; D008813:Mice, Inbred ICR; D008822:Mice, Transgenic; D009474:Neurons / Q000378:metabolism* / Q000648:ultrastructure
chemical_list: D015820:Cadherins; C087310:K cadherin
keywords: Classic cadherins; Cortical arealization; In utero electroporation; Neuronal activity dependent regulation; Somatosensory barrel