A5026501889- Neurogenesis and neuroplasticity mechanisms
- Axon Guidance and Neuronal Signaling
- Neuroscience and Neuropharmacology Research
- Genetic and Kidney Cyst Diseases
- Hedgehog Signaling Pathway Studies
- Retinal Development and Disorders
- Microtubule and mitosis dynamics
- Cellular Mechanics and Interactions
- Developmental Biology and Gene Regulation
- RNA Research and Splicing
- Visual perception and processing mechanisms
- Neural dynamics and brain function
- Cerebrospinal fluid and hydrocephalus
- Cancer, Hypoxia, and Metabolism
- Neuroendocrine regulation and behavior
- MicroRNA in disease regulation
- Cellular transport and secretion
- Photoreceptor and optogenetics research
- Adenosine and Purinergic Signaling
- Neuroscience and Neural Engineering
- Ubiquitin and proteasome pathways
- Genetics and Neurodevelopmental Disorders
- Nerve injury and regeneration
- 3D Printing in Biomedical Research
- Ocular Disorders and Treatments
Sorbonne Université
2012-2024
Institut du Fer à Moulin
2013-2024
Inserm
2013-2024
Centre National de la Recherche Scientifique
1995-2024
Institut du Cerveau
2006-2024
Délégation Ile-de-France Villejuif
2023
Université Paris Cité
1989-2017
Délégation Paris 6
2012
Columbia University
2008
École Normale Supérieure - PSL
2003-2007
In the nervous system of many species, growing axons associate transiently with cellular groupings along their path. Whether this mechanism applies to development corticothalamic and thalamocortical projections is unknown. Using carbocyanine dyes, we studied early growth both corticofugal fibers in hamster embryos. At embryonic day 11.5 (E11.5), invade lateral ganglionic eminence (LGE), medial (MGE). age, sets are not yet contact each other. same time, neurons subdivision GE grow toward...
ABSTRACT An intermediate target for axons leaving the cerebral cortex in embryonic mammals is ganglionic eminence (GE), precursor of basal ganglia. The cues that direct these over initial portion their trajectory are not well understood, but could include both short-range and long-range attractants repellents. In present study, we provide evidence corticofugal might be guided at least partly by a diffusible factor or factors originating lateral GE sulcus between medial ridges (ISS), as...
Consumption of certain substances during pregnancy can interfere with brain development, leading to deleterious long-term neurological and cognitive impairments in offspring. To test whether modulators adenosine receptors affect neural we exposed mouse dams a subtype-selective type 2A receptor (A2AR) antagonist or caffeine, naturally occurring antagonist, lactation. We observed delayed migration insertion γ-aminobutyric acid (GABA) neurons into the hippocampal circuitry first postnatal week...
Type I lissencephaly results from mutations in the doublecortin (DCX) and LIS1 genes. We generated Dcx knockout mice to further understand pathophysiological mechanisms associated with this cortical malformation. is expressed migrating interneurons developing human mouse brains. Video microscopy analyses of such tangentially neuron populations derived medial ganglionic eminence show defects migratory dynamics. Specifically, formation division growth cones, leading production new branches,...
These experiments investigate the capacity of thalamic and cortical structures in a sensory system to process information modality normally associated with another system. Retinal ganglion cells newborn Syrian hamsters were made project permanently main somatosensory (ventrobasal) nucleus. When animals adults, single unit recordings cortices, principal targets ventrobasal The neurons responded visual stimulation distinct receptive fields, their response properties resembled, several...
Origin, timing and direction of neuronal migration during brain development determine the distinct organization adult structures. Changes in these processes might have driven evolution forebrain vertebrates. GABAergic neurons originate from ganglionic eminence mammals migrate tangentially to cortex. We are interested differences similarities tangential patterns across corresponding telencephalic territories reptiles. Using morphological criteria expression Darpp-32, Tbr1, Nkx2.1 Pax6 genes,...
The primary cilium regulates neuronal migration via cyclic AMP production activating protein kinase A at the centrosome.
Recent studies have shown that cells in the intermediate zone (IZ) of embryonic neocortex originate basal telencephalon and migrate tangentially cortical wall (Anderson et al., 1997;Tamamaki 1997; Wichterle 1999). We had previously observed growing axons closely apposed to calbindin-positive, oriented IZ (Métin Godement, 1996), it has been neurites express a glutamate transporter (Furuta 1997). To test if released by corticofugal growth cones could influence tangential cells, we...
Abstract In mammals binocular vision is made possible by the existence in temporal retina of ipsilaterally projecting ganglion cells (IGCs) (with axons that do not cross brain midline and join optic fibers from opposite eye). To learn whether early interactions between each eye play a role generating mixed ipsi + contralateral projection pattern, we studied with horseradish peroxidase origin uncrossed retinal projections mice developed after one was destroyed at very embryonic ages. One...
Patients with Doublecortin (DCX) mutations have severe cortical malformations associated mental retardation and epilepsy. Dcx knockout (KO) mice show no major isocortical abnormalities, but discrete hippocampal defects. We questioned the functional consequences of these defects report here that KO are hyperactive exhibit spontaneous convulsive seizures. Changes in neuropeptide Y calbindin expression, consistent seizure occurrence, were detected a large proportion animals, convulsants,...
In the developing brain, cortical GABAergic interneurons migrate long distances from medial ganglionic eminence (MGE) in which they are generated, to cortex settle. MGE cells express cell adhesion molecule N-cadherin, a homophilic cell–cell that regulates numerous steps of brain development, neuroepithelium morphogenesis synapse formation. N-cadherin is also expressed embryonic territories crossed by during their migration. this study, we demonstrate key player long-distance migration future...
Many genetic forms of congenital deafness affect the sound reception antenna cochlear sensory cells, hair bundle. The resulting deprivation jeopardizes auditory cortex (AC) maturation. Early prosthetic intervention should revive this process. Nevertheless, view assumes that no intrinsic AC deficits coexist with ones, a possibility as yet unexplored. We show here many GABAergic interneurons, from their generation in medial ganglionic eminence up to settlement AC, express two cadherin-related...
The cerebellum comprises a medial domain, called the vermis, flanked by two lateral subdivisions, cerebellar hemispheres. Normal development of vermis involves fusion primordia on dorsal midline. We investigated how fuses midline combining study mid/hindbrain cell movements in avian embryos with analysis normal and mutant mouse embryos. found that, embryos,divergent originating from restricted domain located at boundary produce roof plate domain. Cells migrating anteriorly this region...
During development, most cortical neurons migrate to the plate (CP) radially. CP development is abnormal in reeler and other mutant mice with defective Reelin signaling. secreted by Cajal-Retzius cells binds very low density lipoprotein receptor apolipoprotein E type 2 receptors on surface of cells, inducing tyrosine phosphorylation intracellular Dab1 adapter. As receptors, identification signaling partners hampered genetic redundancy. Using a new vitro embryonic slice culture system, we...
The calcium-stimulated adenylate cyclase 1 (AC1) has been shown to be required for the refinement of retinotopic map, but mechanisms involved are not known. To investigate this question, we devised a retinotectal coculture preparation that reproduces gradual acquisition topographic specificity along rostrocaudal axis superior colliculus (SC). Temporal retinal axons invade entire SC at 4 d in vitro (DIV) and eliminate exuberant branches caudally by 12 DIV. nasal form preferentially rostral or...
Agenesis of the corpus callosum (AgCC) is a frequent brain disorder found in over 80 human congenital syndromes including ciliopathies. Here, we report severe AgCC Ftm/Rpgrip1l knockout mouse, which provides valuable model for Meckel-Grüber syndrome. Rpgrip1l encodes protein ciliary transition zone, essential ciliogenesis several cell types mouse neuroepithelial cells developing forebrain. We show that Rpgrip1l(-/-) associated with disturbed location guidepost dorsomedial telencephalon. This...
Directed cell migration requires sustained polarisation. In migrating cortical interneurons, nuclear movements are directed towards the centrosome that organises primary cilium signalling hub. Primary cilium-elicited signalling, and how it affects migration, remain however ill characterised. Here, we show altering cAMP/cGMP levels in by buffering cAMP, cGMP or locally increasing influences polarity directionality of whereas cAMP apposed compartment alters their motility. Remarkably, identify...
We have shown previously that actomyosin contractility plays an important role in controlling nuclear movements future interneurons born the medial ganglionic eminence (MGE) [Bellion et al.: J Neurosci 2005;25:5691–5699]. Because microtubules are known to control structural and motile properties of migrating neurons, we asked whether alterations dynamic instability would impair MGE cell migration. Migration was analyzed flat cocultures which green-fluorescent-protein-expressing cells migrate...