Henneberger, Christian; Bard, Lucie; Panatier, Aude; Reynolds, James P.; Kopach, Olga; Medvedev, Nikolay I.; Minge, Daniel; Herde, Michel K.; Anders, Stefanie; Kraev, Igor; Heller, Janosch P.; Rama, Sylvain
Extrasynaptic actions of glutamate are limited by high-affinity transporters expressed by perisynaptic astroglial processes (PAPs): this helps maintain point-to-point transmission in excitatory circuits. Memory formation in the brain is associated with synaptic remodeling, but how this affects PAPs and therefore extrasynaptic glutamate actions is poorly understood. Here, we used advanced imaging methods, in situ and in vivo, to find that a classical synaptic memory mechanism, long-term potentiation (LTP), triggers withdrawal of PAPs from potentiated synapses. Optical glutamate sensors combined with patch-clamp and 3D molecular localization reveal that LTP induction thus prompts spatial retreat of astroglial glutamate transporters, boosting glutamate spillover and NMDA-receptor-mediated inter-synaptic cross-talk. The LTP-triggered PAP withdrawal involves NKCC1 transporters and the actin-controlling protein cofilin but does not depend on major Ca2+-dependent cascades in astrocytes. We have therefore uncovered a mechanism by which a memory trace at one synapse could alter signal handling by multiple neighboring connections.
We thank J. Angibaud for organotypic cultures and R. Chereau and J. Tonnesen for help with the STED microscope; also D. Gonzales and the Neurocentre Magendie INSERM U1215 Genotyping Platform, for breeding management and genotyping. This work was supported by the Wellcome Trust Principal Fellowships 101896 and 212251, ERC Advanced Grant 323113, ERC Proof-of-Concept Grant 767372, EC FP7 ITN 606950, and EU CSA 811011 (D.A.R.); NRW-Rückkehrerpogramm, UCL Excellence Fellowship, German Research Foundation (DFG) SPP1757 and SFB1089 (C.H.); Human Frontiers Science Program (C.H., C.J.J., and H.J.); EMBO Long-Term Fellowship (L.B.); Marie Curie FP7 PIRG08-GA-2010-276995 (A.P.), ASTROMODULATION (S.R.); Equipe FRM DEQ 201 303 26519, Conseil Régional d’Aquitaine R12056GG, INSERM (S.H.R.O.); ANR SUPERTri, ANR Castro (ANR-17-CE16-0002), R-13-BSV4-0007-01, Université de Bordeaux, labex BRAIN (S.H.R.O. and U.V.N.); CNRS (A.P., S.H.R.O., and U.V.N.); HFSP, ANR CEXC, and France-BioImaging ANR-10-INSB-04 (U.V.N.); and FP7 MemStick Project No. 201600 (M.G.S.).
Henneberger C, Bard L, Panatier A, et al. LTP induction boosts glutamate spillover by driving withdrawal of perisynaptic astroglia. Neuron. doi:10.1016/j.neuron.2020.08.030
Henneberger, C., Bard, L., Panatier, A., Reynolds, J. P., Kopach, O., Medvedev, N. I., … Rusakov, D. A. (n.d.). LTP induction boosts glutamate spillover by driving withdrawal of perisynaptic astroglia. Neuron. https://doi.org/10.1016/j.neuron.2020.08.030
Henneberger, Christian, Lucie Bard, Aude Panatier, James P. Reynolds, Olga Kopach, Nikolay I. Medvedev, Daniel Minge, et al. “LTP Induction Boosts Glutamate Spillover by Driving Withdrawal of Perisynaptic Astroglia.” Neuron, n.d. https://doi.org/10.1016/j.neuron.2020.08.030.
C. Henneberger et al., “LTP induction boosts glutamate spillover by driving withdrawal of perisynaptic astroglia,” Neuron.
Henneberger C, Bard L, Panatier A, Reynolds JP, Kopach O, Medvedev NI, Minge D, Herde MK, Anders S, Kraev I, Heller JP, Rama S, Zheng K, Jensen TP, Sanchez-Romero I, Jackson CJ, Janovjak HL, Ottersen OP, Nagelhus EA, Oliet SHR, Stewart MG, Nägerl UVa, Rusakov DA. LTP induction boosts glutamate spillover by driving withdrawal of perisynaptic astroglia. Neuron.
Henneberger, Christian, et al. “LTP Induction Boosts Glutamate Spillover by Driving Withdrawal of Perisynaptic Astroglia.” Neuron, Elsevier, doi:10.1016/j.neuron.2020.08.030.