title: Specificity and plasticity of thalamocortical connections in Sema6A mutant mice.
abstract: The establishment of connectivity between specific thalamic nuclei and cortical areas involves a dynamic interplay between the guidance of thalamocortical axons and the elaboration of cortical areas in response to appropriate innervation. We show here that Sema6A mutants provide a unique model to test current ideas on the interactions between subcortical and cortical guidance mechanisms and cortical regionalization. In these mutants, axons from the dorsal lateral geniculate nucleus (dLGN) are misrouted in the ventral telencephalon. This leads to invasion of presumptive visual cortex by somatosensory thalamic axons at embryonic stages. Remarkably, the misrouted dLGN axons are able to find their way to the visual cortex via alternate routes at postnatal stages and reestablish a normal pattern of thalamocortical connectivity. These findings emphasize the importance and specificity of cortical cues in establishing thalamocortical connectivity and the spectacular capacity of the early postnatal cortex for remapping initial sensory representations.
authors.affiliation: Smurfit Institute of Genetics, Trinity College Dublin, Dublin, Ireland.
authors.forename: Graham E
authors.initials: GE
authors.lastname: Little
authors.forename: Guillermina
authors.initials: G
authors.lastname: López-Bendito
authors.forename: Annette E
authors.initials: AE
authors.lastname: Rünker
authors.forename: Noelia
authors.initials: N
authors.lastname: García
authors.forename: Maria C
authors.initials: MC
authors.lastname: Piñon
authors.forename: Alain
authors.initials: A
authors.lastname: Chédotal
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Molnár
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: Mitchell
mesh_terms: D000818:Animals; D001369:Axons / Q000502:physiology*; D005260:Female; D005829:Geniculate Bodies / Q000196:embryology / Q000502:physiology; D051379:Mice; D018345:Mice, Knockout; D009473:Neuronal Plasticity / Q000502:physiology*; D039961:Semaphorins / Q000378:metabolism*; D013687:Telencephalon / Q000196:embryology / Q000502:physiology; D013787:Thalamic Nuclei / Q000196:embryology* / Q000502:physiology; D013788:Thalamus / Q000196:embryology* / Q000502:physiology; D014793:Visual Cortex / Q000196:embryology* / Q000502:physiology; D014795:Visual Pathways / Q000196:embryology* / Q000502:physiology
chemical_list: C504203:Sema6a protein, mouse; D039961:Semaphorins