Intermediate targets in formation of topographic projections: inputs from the thalamocortical system.
Topography of axonal projections has been generally thought to arise from positional information located within the projecting and targeted structures, independent of events along the path or within the axonal bundle. Recent evidence suggests that in the projection from the dorsal thalamus to the neocortex, initial rostrocaudal targeting of axons is regulated at the level of an intermediate target, the subcortical telencephalon. In this system, thalamic axons are spatially positioned within the subcortical telencephalon, partly via interactions between EphAs and ephrin-As, and this positioning apparently determines the rostrocaudal level of the neocortex that the axons will initially target.
INSERM U368, Ecole Normale Supérieure- 46 rue d'Ulm 75230 Paris cedex 05, France.
Sonia
S
Garel
John L R
JL
Rubenstein
D000818:Animals; D001369:Axons / Q000502:physiology*; D051792:Basic Helix-Loop-Helix Proteins; D001931:Brain Mapping; D002352:Carrier Proteins / Q000235:genetics / Q000502:physiology; D002540:Cerebral Cortex / Q000033:anatomy & histology* / Q000196:embryology; D020439:Growth Cones; D018398:Homeodomain Proteins / Q000502:physiology; D006801:Humans; D051379:Mice; D008817:Mice, Mutant Strains; D008959:Models, Neurological; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000502:physiology; D009434:Neural Pathways / Q000033:anatomy & histology* / Q000196:embryology; D036081:Receptors, Eph Family / Q000502:physiology; D013788:Thalamus / Q000033:anatomy & histology* / Q000196:embryology; D014157:Transcription Factors / Q000172:deficiency / Q000502:physiology
D051792:Basic Helix-Loop-Helix Proteins; D002352:Carrier Proteins; D018398:Homeodomain Proteins; D009419:Nerve Tissue Proteins; D036081:Receptors, Eph Family; D014157:Transcription Factors; C088334:Distal-less homeobox proteins; C491183:NEUROG2 protein, human; C102938:Neurog2 protein, mouse