TY - JOUR T1 - Excitatory amino acid transporter EAAT5 improves temporal resolution in the retina JF - eneuro JO - eNeuro DO - 10.1523/ENEURO.0406-21.2021 SP - ENEURO.0406-21.2021 AU - Jana Gehlen AU - Christoph Aretzweiler AU - Anja Mataruga AU - Christoph Fahlke AU - Frank Müller Y1 - 2021/11/11 UR - http://www.eneuro.org/content/early/2021/11/10/ENEURO.0406-21.2021.abstract N2 - Excitatory amino acid transporters (EAATs) remove glutamate from the synaptic cleft. In the retina, EAAT1 and EAAT2 are considered the major glutamate transporters. However, it has not yet been possible to determine how EAAT5 shapes the retinal light responses because of the lack of a selective EAAT5 blocker or EAAT5 knock-out animal model. In this study, EAAT5 was found to be expressed in a punctate manner close to release sites of glutamatergic synapses in the mouse retina. Light responses from retinae of wild-type and of a newly generated model with a targeted deletion of EAAT5 (EAAT5-/-) were recorded in vitro using multi-electrode arrays. Flicker resolution was considerably lower in EAAT5-/- retinae than in wild-type retinae. The close proximity to the glutamate release site makes EAAT5 an ideal tool to improve temporal information processing in the retina by controlling information transfer at glutamatergic synapses.Significance statementNeurons communicate with other neurons at synaptic connections by release of neurotransmitters acting at postsynaptic receptors. Neurotransmitters are removed from the synaptic cleft by transporters. Using the mouse retina as a model for the central nervous system, the role of EAAT5 that functions as glutamate transporter and as glutamate-gated ion channel was investigated in retinal information processing. EAAT5 was found highly localized to the glutamate release site at retinal synapses, suggesting a role in shaping of synaptic responses. In a mouse model devoid of EAAT5, temporal resolution of the retina was severely compromised. The results demonstrate that glutamate transporters like EAAT5 can exert a tremendous effect on information processing in neuronal networks. ER -