Synapse maturation by activity-dependent ectodomain shedding of SIRPα.

In this study, the authors document how SIRPα, a cell-adhesion molecule, participates in the late maturation of hippocampal excitatory synapses. They find that in response to activity, SIRPα sheds its ectodomain, which acts presynaptically to promote maturation in a process that requires CaM kinase, matrix metalloproteinases and the presynaptic receptor CD47.