Structures of synaptic vesicle protein 2A and 2B bound to anticonvulsants

Author:Mittal A, Martin MF, Levin EJ, Adams C, Yang M, Provins L, Hall A, Procter M, Ledecq M, Hillisch A, Wolff C, Gillard M, Horanyi PS, Coleman JA.

Journal:

Nat Struct Mol Biol. 2024 Dec;31(12):1964-1974.

Abstract:Epilepsy is a common neurological disorder characterized by abnormal activity of neuronal networks, leading to seizures. The racetam class of anti-seizure medications bind specifically to a membrane protein found in the synaptic vesicles of neurons called synaptic vesicle protein 2 (SV2) A (SV2A). SV2A belongs to an orphan subfamily of the solute carrier 22 organic ion transporter family that also includes SV2B and SV2C. The molecular basis for how anti-seizure medications act on SV2s remains unknown. Here we report cryo-electron microscopy structures of SV2A and SV2B captured in a luminal-occluded conformation complexed with anticonvulsant ligands. The conformation bound by anticonvulsants resembles an inhibited transporter with closed luminal and intracellular gates. Anticonvulsants bind to a highly conserved central site in SV2s. These structures provide blueprints for future drug design and will facilitate future investigations into the biological function of SV2s.