Synaptic vesicle 2-related protein (SVOP) of the Major Facilitator Superfamily
Synaptic vesicle 2 (SV2)-related protein (SVOP) is a transporter-like nucleotide binding protein that localizes to neurotransmitter-containing vesicles. Like SV2, SVOP is expressed in all brain regions, with highest levels in cerebellum, hindbrain and pineal gland. Studies with knockout mice suggets that SVOP may perform a subtle function that is not necessary for survival under normal conditions, since mice lacking SVOP are viable, fertile, and phenotypically normal. SVOP shares structural similarity to the solute carrier family 22 (SLC22), a large family of organic cation and anion transporters. This SVOP subfamily belongs to the Metazoan Synaptic Vesicle Glycoprotein 2 (SV2) and related small molecule transporter family (SV2-like) of the Major Facilitator Superfamily (MFS) of membrane transport proteins. MFS proteins are thought to function through a single substrate binding site, alternating-access mechanism involving a rocker-switch type of movement.
Feature 1:putative chemical substrate binding pocket [chemical binding site]
Evidence:
Comment:based on the structures of MFS transporters with bound substrates, substrate analogs, and/or inhibitors
Comment:since MFS proteins facilitate the transport of many different substrates including ions, sugar phosphates, drugs, neurotransmitters, nucleosides, amino acids, and peptides, the residues involved in substrate binding may not be strictly conserved among superfamily members
Comment:the substrate binding site or translocation pore has access to both sides of the membrane in an alternating fashion through a conformational change of the MFS transporter
Jiyao W et al.(2023). "The conserved domain database in 2023.",