Actualités
Séminaires

Dans le cadre des séminaires hebdomadaires du LabEx MAbImprove, nous vous rappelons que le prochain séminaire externe aura lieu mercredi 19 avril à 9h30 à Tours (salle TO Conf 2 - Fac de Médecine) et retransmis en visioconférence à Montpellier (salle de conférence de l'IRCM). Exceptionnellement, nous assisterons à deux présentations successives. Invités par Lucie Pellissier, Clive R Bramham - Professor, Head of Neuroscience Research Group, Department of Biomedicine, University of Bergen, Norway - Molecular Control of Synaptic Plasticity, nous présentera ses travaux sur le thème "The Arc of Synaptic Memory: From Hub Protein to Retroviral-like Capsid" et Antonino Cattaneo - Professor of Neurobiology at the Scuola Normale Superiore (Pisa), European Brain Research Institute Roma, and also Director of the Biology Lab Bio@SnS nous présentera ses travaux sur un thème dont le titre vous sera communiqué ultérieurement. 

Abstract ( Clive R Bramham)

The immediate early gene, Arc, is a pivotal regulator of synaptic plasticity, memory, and cognitive flexibility. But what is Arc protein?  How does it work? Inside the neuron, Arc is a protein interaction hub and dynamic regulator of intracellular signaling in synaptic plasticity. In remarkable contrast, Arc can also self-assemble into retrovirus-like capsids that are released in extracellular vesicles and capable of intercellular transfer of RNA. Elucidation of the molecular basis of Arc hub and capsid functions, and the relationship between them, is vital for progress. The talk will present recent findings on Arc molecular structure-function regulation of oligomerization, and synaptic function in neurons. A major goal is to develop new tools for probing Arc function. To this end, we are evaluating anti-Arc nanobodies, selected from immunized Alpaca, for various applications.  The bacterially expressed, purified nanobodies bind to the retroviral homology capsid domain of Arc with high-affinity.  Crystal structure analysis shows that one of the nanobodies (Arc Nb-H11) binds to the ligand binding pocket of the capsid domain, important for Arc protein-protein interactions and signaling. Arc Nb-H11 expressed as intrabody in HEK 293 cells also binds selective to the capsid domain and allows immunoprecipitation of full-length Arc.