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DGK? Catalytic Activity Is Required for Efficient Recycling of Presynaptic Vesicles at Excitatory Synapses.

ABSTRACT: Synaptic transmission relies on coordinated coupling of synaptic vesicle (SV) exocytosis and endocytosis. While much attention has focused on characterizing proteins involved in SV recycling, the roles of membrane lipids and their metabolism remain poorly understood. Diacylglycerol, a major signaling lipid produced at synapses during synaptic transmission, is regulated by diacylglycerol kinase (DGK). Here, we report a role for DGK? in the mammalian CNS in facilitating recycling of presynaptic vesicles at excitatory synapses. Using synaptophysin- and vGlut1-pHluorin optical reporters, we found that acute and chronic deletion of DGK? attenuated the recovery of SVs following neuronal stimulation. Rescue of recycling kinetics required DGK? kinase activity. Our data establish a role for DGK catalytic activity at the presynaptic nerve terminal in SV recycling. Altogether, these data suggest that DGK? supports synaptic transmission during periods of elevated neuronal activity.

SUBMITTER: Goldschmidt HL

PROVIDER: S-EPMC4715728 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature

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