Neurogenin2 Specifies the Connectivity of Thalamic Neurons by Controlling Axon Responsiveness to Intermediate Target Cues

Julie Seibt (1, 2) , Carol Schuurmans (3) , Gérard Gradwhol (4) , Colette Dehay (1, 2) , Pierre Vanderhaeghen (5) , François Guillemot (3) , Franck Polleux (1, 2, 6)

1 Cerveau et vision
2 Hôpital neurologique et neurochirurgical Pierre Wertheimer [CHU - HCL]
3 IGBMC - Institut de génétique et biologie moléculaire et cellulaire
4 Ontogénèse et pathologie du système digestif : rôle du microenvironnement cellulaire et moléculaire
5 IRIBHM - Institut de Recherche Interdisciplinaire en Biologie Humaine et moléculaire = Insitute of Interdisciplinary Research [Bruxelles, Belgique]
6 UNC - University of North Carolina [Chapel Hill]

Many lines of evidence indicate that important traits of neuronal phenotype, such as cell body position and neurotransmitter expression, are specified through complex interactions between extrinsic and intrinsic genetic determinants. However, the molecular mechanisms specifying neuronal connectivity are less well understood at the transcriptional level. Here we demonstrate that the bHLH transcription factor Neurogenin2 cell autonomously specifies the projection of thalamic neurons to frontal cortical areas. Unexpectedly, Ngn2 determines the projection of thalamic neurons to specific cortical domains by specifying the responsiveness of their axons to cues encountered in an intermediate target, the ventral telencephalon. Our results thus demonstrate that in parallel to their well-documented proneural function, bHLH transcription factors also contribute to the specification of neuronal connectivity in the mammalian brain.

Domaines: Sciences du Vivant [q-bio]

Julie Seibt, Carol Schuurmans, Gérard Gradwhol, Colette Dehay, Pierre Vanderhaeghen, et al.. Neurogenin2 Specifies the Connectivity of Thalamic Neurons by Controlling Axon Responsiveness to Intermediate Target Cues. Neuron, 2003, 39 (3), pp.439-452. ⟨10.1016/s0896-6273(03)00435-5⟩. ⟨hal-04150878⟩