title: Ephrin-as guide the formation of functional maps in the visual cortex.
abstract: Ephrin-As and their receptors, EphAs, are expressed in the developing cortex where they may act to organize thalamic inputs. Here, we map the visual cortex (V1) in mice deficient for ephrin-A2, -A3, and -A5 functionally, using intrinsic signal optical imaging and microelectrode recording, and structurally, by anatomical tracing of thalamocortical projections. V1 is shifted medially, rotated, and compressed and its internal organization is degraded. Expressing ephrin-A5 ectopically by in utero electroporation in the lateral cortex shifts the map of V1 medially, and expression within V1 disrupts its internal organization. These findings indicate that interactions between gradients of EphA/ephrin-A in the cortex guide map formation, but that factors other than redundant ephrin-As are responsible for the remnant map. Together with earlier work on the retinogeniculate map, the current findings show that the same molecular interactions may operate at successive stages of the visual pathway to organize maps.
authors.affiliation: W. M. Keck Foundation Center for Integrative Neuroscience, Department of Physiology, University of California, San Francisco, San Francisco, California 94143, USA.
authors.forename: Jianhua
authors.initials: J
authors.lastname: Cang
authors.forename: Megumi
authors.initials: M
authors.lastname: Kaneko
authors.forename: Jena
authors.initials: J
authors.lastname: Yamada
authors.forename: Georgia
authors.initials: G
authors.lastname: Woods
authors.forename: Michael P
authors.initials: MP
authors.lastname: Stryker
authors.forename: David A
authors.initials: DA
authors.lastname: Feldheim
mesh_terms: D000375:Aging / Q000378:metabolism / Q000502:physiology; D000818:Animals; D000831:Animals, Newborn; D001931:Brain Mapping; D047108:Embryonic Development; D036383:Ephrin-A2 / Q000172:deficiency / Q000378:metabolism / Q000502:physiology*; D036384:Ephrin-A3 / Q000172:deficiency / Q000378:metabolism / Q000502:physiology*; D036386:Ephrin-A5 / Q000172:deficiency / Q000378:metabolism / Q000502:physiology*; D008024:Ligands; D051379:Mice; D018345:Mice, Knockout; D012160:Retina / Q000502:physiology; D009435:Synaptic Transmission / Q000502:physiology; D013788:Thalamus / Q000196:embryology / Q000254:growth & development / Q000502:physiology; D014793:Visual Cortex / Q000196:embryology* / Q000254:growth & development / Q000502:physiology*
chemical_list: D036383:Ephrin-A2; D036384:Ephrin-A3; D036386:Ephrin-A5; D008024:Ligands