Sleep and Synaptic Homeostasis: Structural Evidence in Drosophila

Department of Psychiatry, University of Wisconsin, Madison, WI 53719, USA.
Science (Impact Factor: 33.61). 06/2011; 332(6037):1576-81. DOI: 10.1126/science.1202839
Source: PubMed


The functions of sleep remain elusive, but a strong link exists between sleep need and neuronal plasticity. We tested the hypothesis that plastic processes during wake lead to a net increase in synaptic strength and sleep is necessary for synaptic renormalization. We found that, in three Drosophila neuronal circuits, synapse size or number increases after a few hours of wake and decreases only if flies are allowed to sleep. A richer wake experience resulted in both larger synaptic growth and greater sleep need. Finally, we demonstrate that the gene Fmr1 (fragile X mental retardation 1) plays an important role in sleep-dependent synaptic renormalization.

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