title: Connecting thalamus and cortex: the role of ephrins.
abstract: The complex task of wiring up the brain during embryonic development is achieved by a multitude of guidance signals acting in complex combinations to drive growing axons to their proper targets. The somatosensory system provides an extensively studied model system featuring many universal mechanisms of neural development. In rodents, it constitutes an important model to study how precise topographic connections are achieved. Recent evidence suggests that the Eph/ephrin family of guidance molecules is of pivotal importance for the development of the somatosensory system. Members of Eph/ephrin family are thought to be involved in the global presorting of thalamic axons projecting to the cortex, in labeling specific cortical areas for innervation, in providing topographic cues within the target area, and in distinguishing cortical layers for intracortical wiring. The Eph/ephrin system also seems to contribute to the formation of specific corticothalamic feedback projections. So far, the functions of only a few members of the Eph/ephrin family have been examined, but expression analysis indicates complex combinatorial effects of these signaling molecules. Understanding the Eph/ephrin wiring code is expected to yield new insights into the development and plasticity of brain circuits involved in higher functions.
authors.affiliation: Departamento de Anatomia, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil. daniuzi@anato.ufrj.br
authors.forename: Daniela
authors.initials: D
authors.lastname: Uziel
authors.forename: Patricia
authors.initials: P
authors.lastname: Garcez
authors.forename: Roberto
authors.initials: R
authors.lastname: Lent
authors.forename: Christiane
authors.initials: C
authors.lastname: Peuckert
authors.forename: Ronny
authors.initials: R
authors.lastname: Niehage
authors.forename: Franco
authors.initials: F
authors.lastname: Weth
authors.forename: Jürgen
authors.initials: J
authors.lastname: Bolz
mesh_terms: D000818:Animals; D001369:Axons / Q000502:physiology*; D036342:Ephrins / Q000378:metabolism*; D006801:Humans; D009434:Neural Pathways; D013003:Somatosensory Cortex / Q000033:anatomy & histology* / Q000378:metabolism; D013788:Thalamus / Q000033:anatomy & histology* / Q000378:metabolism
chemical_list: D036342:Ephrins