Dscam mediates remodeling of glutamate receptors in Aplysia during de novo and learning-related synapse formation.

Howard Hughes Medical Institute, Department of Neuroscience, College of Physicians and Surgeons of Columbia University, 1051 Riverside Drive, New York, NY 10032, USA.
Neuron (Impact Factor: 15.77). 03/2009; 61(4):527-40. DOI: 10.1016/j.neuron.2009.01.010
Source: PubMed

ABSTRACT Transsynaptic interactions between neurons are essential during both developmental and learning-related synaptic growth. We have used Aplysia neuronal cultures to examine the contribution of transsynaptic signals in both types of synapse formation. We find that during de novo synaptogenesis, specific presynaptic innervation is required for the clustering of postsynaptic AMPA-like but not NMDA-like receptors. We further find that the cell adhesion molecule Dscam is involved in these transsynaptic interactions. Inhibition of Dscam either pre- or postsynaptically abolishes the emergence of synaptic transmission and the clustering of AMPA-like receptors. Remodeling of both AMPA-like and NMDA-like receptors also occurs during learning-related synapse formation and again requires the reactivation of Dscam-mediated transsynaptic interactions. Taken together, these findings suggest that learning-induced synapse formation recapitulates, at least in part, aspects of the mechanisms that govern de novo synaptogenesis.

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