Excitatory amino acid transporter 5 (EAAT5)

Excitatory amino acid transporter 5 (EAAT5) is a member of the SLC1 family of high-affinity glutamate transporters, encoded by the SLC1A7 gene in humans[3][5][7]. EAAT5 is primarily expressed in the retina, especially in photoreceptors, bipolar cells, and amacrine cells, where it regulates glutamatergic neurotransmission and visual signal processing by mediating glutamate uptake and functioning as a glutamate-activated chloride channel[4][5][7]. This dual function provides both slow glutamate transport and large chloride conductance, resulting in hyperpolarization and feedback inhibition of synaptic output, particularly in the rod pathway[2][3][4][5]. Unlike other EAATs, EAAT5’s prominent chloride conductance may act as an inhibitory glutamate receptor in the retina[4][5]. Although traditionally considered retina-specific, recent evidence indicates a broader tissue distribution, including the testis, liver, kidney, heart, lung, intestine, and skeletal muscle, although its physiological roles in these tissues remain to be fully determined[3]. EAAT5 has been proposed as a potential neuroprotective target in neurodegenerative diseases, such as Parkinson’s disease, but as of now, no drugs or clinical biomarkers are established specifically for EAAT5[4]. There are currently no known disease-causing mutations or direct pharmacological modulators approved for EAAT5[4][3].

Other names

EAAT5SLC1A7Glutamate transporter EAAT5

Glutamate uptake inhibition/modulation; Allosteric modulation of transporter activity