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Erwan Bézard, directeur de l'IMN, est à l'honneur dans le magazine de l'Inserm pour ses travaux sur les maladies neurodégénératives.
Retrouvez la vidéo que la Fédération Bordeaux Neurocampus lui consacrait ici : https://youtu.be/RM-O2D44s8E

Nature. 2016 Jul 21;535(7612):420-4.
Prefrontal neuronal assemblies temporally control fear behaviour.
Dejean C, Courtin J, Karalis N, Chaudun F, Wurtz H, Bienvenu TC, Herry C.

Over the past decades, numerous studies demonstrated a critical role of the medial prefrontal cortex (mPFC) in regulation emotional behaviour, in particular learned fear responses. In these studies, in which the neuronal substrates of aversive learning were investigated, encoding of fear behavior was assumed to rely on the activity of single neurons through a rate coding mechanism in which the sole firing rate determine the behavioral output. This form of neuronal cording is strongly limited by the fact that over long distances, rate codes are not optimal for the fast information transmission that is required for rapid behavioural adaptation when facing threatening stimuli. In addition to this rate coding mechanism, neurons with different and specific firing sequences may cooperate and collectively provide information, a phenomenon referred to as "temporal coding".

In temporal coding, precise timing of firing is important, whereas average firing rates can remain stable. Assemblies of neurons enable temporal coding, and one of its obvious advantages is its great flexibility. Thus, neurons might rapidly switch between multiple functional networks according to sensory and internal inputs and determine specific behavioral outputs. Brain oscillations are thought to be instrumental in temporal coding by binding cell assemblies, organizing individual firing into meaningful collective activity, and coordinating remote areas. Whereas temporal coding has been described for sensory processing and spatial learning, its role in encoding emotional behaviour is virtually unknown.

To address this question we use a combination of single-unit and local field potential recordings along with optogenetic manipulations to show that, in the dmPFC, expression of conditioned fear is causally related to the organization of neurons into functional assemblies. During fear behaviour, the development of 4 Hz oscillations coincides with the activation of assemblies nested in the ascending phase of the oscillation. The selective optogenetic inhibition of dmPFC neurons during the ascending or descending phases of this oscillation blocks and promotes conditioned fear responses, respectively. These results identify a novel phase-specific coding mechanism, which dynamically regulates the development of dmPFC assemblies to control the precise timing of fear responses.

Les MRSEI sont dédiés au "montage de réseaux scientifiques européens ou internationaux" (MRSEI). Il vise à faciliter l'accès des chercheurs français aux programmes de financement européens (Horizon 2020 principalement) et/ou internationaux.

Nathalie Sans (Equipe Montcouquiol-Sans), Lauréate ANR 2016 avec le projet NanoPlanSYN

Projet NanoPlanSYN : Rôle de la voie de signalisation de la polarité planaire dans l’organisation dynamique de la synapse et l’intégration de l’information synaptique: des mécanismes fondamentaux aux conséquences pathophysiologiques

Aude PANATIER (Equipe Oliet), Lauréate ANR 2016 avec son projet ASTRODOM:
Exploration fonctionnelle du domaine astrocytaire

Sophie TRONEL (Equipe Abrous), Lauréate ANR 2016 avec son projet ReconsoNeuro:
Rôle de la neurogénèse hippocampique dans la reconsolidation de la mémoire

Projet ORUPS: Représentation sensorielle lors d'états psychotiques

Lieu: Neurocentre Magendie Seminar room

from Department of Pharmacology and Therapeutics (McGill University, Canada) will give a presentation entitled 'Nuclear G proteins in cardiac transcriptional regulation'

Invitant : Stéphane Oliet, Team leader: Glia-neuron relations (Neurocentre Magendie)

Pour plus de détails: http://www.bordeaux-neurocampus.fr/fr/manifestations-scientifiques/seminaires-2016/terry-hebert.html

Development and plasticity of the nervous system critically depends on the neuronal cytoskeleton. The organization and dynamic remodeling of the neuronal cytoskeleton contributes to all morphological and functional changes in neurons, including migration, polarization, axon outgrowth, dendrite development and synapse formation. The neuronal cytoskeleton provides tracks for intracellular transport, sets up local cues to position organelles, acts as a signaling device and generates cellular forces that are fundamental to all aspects of neuronal function. Cytoskeleton remodeling and axonal trafficking have emerged as one of the most exciting and rapidly moving fields in cellular neurobiology. This field is experiencing a revolution in molecular, genetic and imaging technologies for analysing the dynamics of these processes during neuronal development and plasticity. The study of the molecular mechanisms of cytoskeletal dynamics and neuronal trafficking are also key to understanding what goes wrong in many neurodevelopmental and neurodegenerative diseases.

With participation of Mireille Montcouquiol

EUROGENESIS 3rd Conference will end the celebrations of the 50th anniversary of adult neurogenesis discovery by gathering worldwide leaders of this exciting field

The findings of neural stem cells in the adult mammalian central nervous system changed our perception of brain plasticity and function. For five decades, research on adult neurogenesis and neural stem cells has therefore been leading to an ever expanding field of discoveries that have influenced many domains of neuroscience and developmental biology.

Informations, Program and Registration: http://www.eurogenesis.com

Registration: Deadline June 15th, 2016
Abstract Submission: Deadline May 27th, 2016

Local organization : Nora Abrous - Sophie Tronel - Florence Béranger

Lieu: Neurocentre Magendie Seminar room

from Howard Hugues Medical Institute (Washington) will give a presentation entitled 'Chemogenetic ion channel tools for neurobiology'

Invitant : Guillaume LUCAS (Equipe Abrous), Neurocentre Magendie

Pour plus de détails: http://www.bordeaux-neurocampus.fr/fr/manifestations-scientifiques/seminaires-2016/scott-sternson.html