A5072556745- Neuroscience and Neuropharmacology Research
- Neurogenesis and neuroplasticity mechanisms
- Retinal Development and Disorders
- Vestibular and auditory disorders
- Transcranial Magnetic Stimulation Studies
- Nerve injury and regeneration
- Neuroscience and Neural Engineering
- Ion channel regulation and function
- Neurobiology and Insect Physiology Research
- Neural dynamics and brain function
- Neuropeptides and Animal Physiology
- Muscle activation and electromyography studies
- Axon Guidance and Neuronal Signaling
- Photoreceptor and optogenetics research
- Cell death mechanisms and regulation
- RNA Interference and Gene Delivery
- Genetics and Neurodevelopmental Disorders
- Neurological disorders and treatments
- Mitochondrial Function and Pathology
- Memory and Neural Mechanisms
- RNA regulation and disease
- Pain Mechanisms and Treatments
- EEG and Brain-Computer Interfaces
- Signaling Pathways in Disease
- Genetic Neurodegenerative Diseases
Centre National de la Recherche Scientifique
2009-2023
Sorbonne Université
2010-2023
Adaptation Biologique et Vieillissement
2014-2023
Institut de Biologie Paris-Seine
2019-2023
Sorbonne Paris Cité
2023
Unit of Functional and Adaptive Biology
2005-2018
Université Paris Cité
2013
Laboratoire de Biologie du Développement
1996-2003
Université Libre de Bruxelles
1999
Laboratoire de Géologie de l’École Normale Supérieure
1999
The possible role of cyclic nucleotides as second messengers mediating growth cone turning was studied by producing an asymmetric distribution across the cone. A repetitive pulse application method developed to produce microscopic chemical gradients near embryonic Xenopus neurons in cell culture. When picoliters a solution containing 20 mM dibutyryl cAMP (dB-cAMP), membrane-permeable analog cAMP, were repetitively ejected from micropipette cone, neurite consistently directed toward pipette....
In the cerebellum, parallel fiber-Purkinje cell synapse can undergo long-term synaptic plasticity suggested to underlie motor learning and resulting from variations in intracellular calcium concentration ([Ca 2+ ] i ). Ca binding proteins are enriched but their role information processing is not clear. Here, we show that mice deficient calretinin (Cr −/− ) impaired tests of coordination. An impairment homeostasis Cr Purkinje cells was supported by high -saturation calbindin-D28k these cells....
Neuronal maturation during development is a multistep process regulated by transcription factors. The factor RORα (retinoic acid-related orphan receptor α) necessary for early Purkinje cell (PC) but also expressed throughout adulthood. To identify the role of in mature PCs, we used Cre-lox mouse genetic tools vivo that delete it specifically from PCs between postnatal days 10–21. Up to 14 d age, differences mutant and control were not detectable: both mono-innervated climbing fibers (CFs)...
Biomimetic patterns of weak magnetic pulses modify gene expression and need cryptochrome to induce cerebellar reinnervation.
Neurotrophins constitute a family of trophic factors with profound effects on the survival and differentiation nervous system. Addition brain-derived neurotrophic factor (BDNF) or neurotrophin-3 (NT-3), but not nerve growth (NGF), increased embryonic Xenopus spinal neurons in culture, although all three neurotrophins enhanced neurite outgrowth. Here we report that also exert acute actions morphology motility 1-day-old cultured neurons. Bath application BDNF induced extensive formation...
Recovery of complex neural function after injury to the adult CNS is limited by minimal spontaneous axonal regeneration and/or sprouting from remaining pathways. In contrast, developing displays reorganization following lesion, in which uninjured axons can develop new projections appropriate target neurons and provide partial recovery behaviours. Similar pathways be induced mature CNS, providing models optimize post-injury functions. After unilateral transection a olivocerebellar path...
Magnetic brain stimulation is a promising treatment for neurological and psychiatric disorders. However, better understanding of its effects at the individual neuron level essential to improve clinical application. We combined focal low-intensity repetitive transcranial magnetic (LI-rTMS) rat somatosensory cortex with intracellular recordings subjacent pyramidal neurons in vivo. Continuous 10 Hz LI-rTMS reliably evoked firing ∼4-5 during period induced durable attenuation synaptic activity...
When exogenous ACh is loaded into the cytoplasm of cultured amphibian myocytes and fibroblasts, cells undergo spontaneous quantal secretion, as detected by appearance pulsatile membrane currents in Xenopus which are manipulated contact with cells. These resemble many ways miniature endplate (MEPCs) observed at developing neuromuscular synapses formed on these myocytes. Analyses frequency, amplitude, time course suggests similarity cellular mechanisms involved packaging secretion quanta...
During developmental synaptogenesis, the pre- and postsynaptic cells undergo specific interactions that lead to establishment of mature circuit. We have studied roles in establishing this innervation by using an vitro model synaptic development. describe climbing fiber (CF)-Purkinje cell (PC) synaptogenesis cultured mouse hindbrain explants show competition occurs during early development vitro. By manipulating maturation stage each partners a coculture experimental paradigm, we found...
Abstract In the cerebellum, mRNAs for neurotrophin‐3 (NT‐3) and its high‐affinity tyrosine kinase receptor trk C are expressed by both differentiated granule cells of internal cell layer (IGL) their precursors in external germinal (EGL). We have investigated effects chronic application exogenous NT‐3 vivo on cerebellar genesis differentiation. was applied to posterior surface rat cerebellum from P6 onwards using Elvax implants. At P10 EGL lobules VII VIII significantly reduced thickness...
The development of GABAergic signals includes receptor subunits reorganization, alterations (Cl-)I levels and GABA depolarizing-excitatory/hyperpolarizing-inhibitory shift. This sequence is altered in animal models autism stressing its relevance to disorders. Here, using cell-attached single GABAA channel recordings cerebellar Purkinje cells (PCs), we report the presence males females two conductance (18 & 10 pS), former being dominant newborns latter young-adults. shift like...
Abstract In the adult mammalian central nervous system, reinnervation and recovery from trauma is limited. During development, however, postlesion plasticity may generate alternate paths, providing models to investigate reinnervating axon–target interactions. After unilateral transection of neonatal rat olivocerebellar path, axons ipsilateral inferior olive grow into denervated hemicerebellum develop climbing fibre (CF)‐like arbors on Purkinje cells (PCs). However, synaptic function extent...
Abstract Some immune system proteins have recently been implicated in the development and plasticity of neuronal connections. Notably, major histocompatibility complex 1 (MHC class 1) shown to be involved synaptic hippocampus projection patterns visual system. We examined possible role for MHC one well‐characterized example exuberance subsequent refinement, climbing fiber (CF) Purkinje cell (PC) synapse. Cerebella from adult mice deficient two genes, H2‐D1 H2‐K1 , β2‐microglobulin gene were...
Synaptic partner selection and refinement of projections are important in the development precise functional neuronal connections. We investigated formation new synaptic connections a relatively mature system to test whether developmental events can be recapitulated at later stages (i.e., after organization has been established), using model postlesional reinnervation olivo-cerebellar pathway. During this pathway, between climbing fibers (CFs) Purkinje cells (PCs) diffuse redundant before...
In Purkinje cells from cerebellar slice cultures, low-threshold Ca2+ spike (LTS) gives rise to complex bursts in the soma that resemble induced by climbing fibers stimulation. We show LTS is reduced T-type and R-type channel blockers (SNX-482, nickel, or mibefradil). propose generated openings of channels (α-1G and/or α-1I subunits) (α-1E subunit isoforms with a weak sensitivity SNX-482 nickel). Using mibefradil we fiber stimulation activates LTS, which contributes shape response. This entry...
Programmed neuronal cell death is common during development, and thought to be important in the elimination of errors axonal projection, position sculpting circuits. However, potential importance programmed for complex behaviour adult animal has never been addressed. We studied motor abilities a strain transgenic mice with overexpression human Bcl-2 protein, which have supernumerary neurons due reduced developmental death. Our results show that these clear deficiency fine timing coordination...
Abstract We have used a model of postlesional reinnervation to observe the interactions between synaptic partners during neosynaptogenesis determine how developmental states pre‐ and postsynaptic cells influence circuit maturation. After unilateral transection neonatal rat olivocerebellar pathway (pedunculotomy), axons from remaining ipsilateral inferior olive grow into denervated hemicerebellum develop climbing fibre (CF) terminal arbors on Purkinje (PCs) at later stage development than...