Slc17a7
Developmental stage
Expression in brain increases progressively from four days to adulthood.
Function
Multifunctional transporter that transports L-glutamate as well as multiple ions such as chloride, proton, potassium, sodium and phosphate (PubMed:25433636, PubMed:29273736, PubMed:29642010, PubMed:33440152). At the synaptic vesicle membrane, mainly functions as an uniporter which transports preferentially L-glutamate but also phosphate from the cytoplasm into synaptic vesicles at presynaptic nerve terminals of excitatory neural cells (PubMed:15103023, PubMed:15118123, PubMed:25433636, PubMed:29642010). The L-glutamate or phosphate uniporter activity is electrogenic and is driven by the proton electrochemical gradient, mainly by the electrical gradient established by the vacuolar H(+)-ATPase across the synaptic vesicle membrane (PubMed:29642010). In addition, functions as a chloride channel that allows a chloride permeation through the synaptic vesicle membrane that affects the proton electrochemical gradient and promotes synaptic vesicles acidification (PubMed:25433636, PubMed:29273736, PubMed:29642010). Moreover, may function as a K(+)/H(+) antiport allowing to maintain the electrical gradient and to decrease chemical gradient and therefore sustain vesicular glutamate uptake (By similarity). The vesicular K(+)/H(+) antiport activity is electroneutral (By similarity). At the plasma membrane, following exocytosis, functions as a symporter of Na(+) and phosphate from the extracellular space to the cytoplasm allowing synaptic phosphate homeostasis regulation (PubMed:29642010, PubMed:33440152). The symporter activity is driven by an inside negative membrane potential and is electrogenic (PubMed:29642010). Is necessary for synaptic signaling of visual-evoked responses from photoreceptors (PubMed:17611277).
Sequence Similarities
Belongs to the major facilitator superfamily. Sodium/anion cotransporter family. VGLUT subfamily.
Tissue Specificity
Expressed in hippocampus (at protein level). Expressed in the molecular layer of the cerebellum and in retina.
Cellular localization
- Cytoplasmic vesicle
- Secretory vesicle
- Synaptic vesicle membrane
- Cell membrane
- Multi-pass membrane protein
- Synapse
- Synaptosome
Alternative names
Bnpi, Vglut1, Slc17a7, Vesicular glutamate transporter 1, VGluT1, Brain-specific Na(+)-dependent inorganic phosphate cotransporter, Solute carrier family 17 member 7