| RRC ID |
87485
|
| Author |
Niklaus S, Glasauer SMK, Kovermann P, Farshori KF, Cadetti L, Früh S, Rieser NN, Gesemann M, Zang J, Fahlke C, Neuhauss SCF.
|
| Title |
Glutamate transporters are involved in direct inhibitory synaptic transmission in the vertebrate retina.
|
| Journal |
Open Biol
|
| Abstract |
In the central nervous system of vertebrates, glutamate serves as the primary excitatory neurotransmitter. However, in the retina, glutamate released from photoreceptors causes hyperpolarization in post-synaptic ON-bipolar cells through a glutamate-gated chloride current, which seems paradoxical. Our research reveals that this current is modulated by two excitatory glutamate transporters, EAAT5b and EAAT7. In the zebrafish retina, these transporters are located at the dendritic tips of ON-bipolar cells and interact with all four types of cone photoreceptors. The absence of these transporters leads to a decrease in ON-bipolar cell responses, with eaat5b mutants being less severely affected than eaat5b/eaat7 double mutants, which also exhibit altered response kinetics. Biophysical investigations establish that EAAT7 is an active glutamate transporter with a predominant anion conductance. Our study is the first to demonstrate the direct involvement of post-synaptic glutamate transporters in inhibitory direct synaptic transmission at a central nervous system synapse.
|
| Volume |
14(7)
|
| Pages |
240140
|
| Published |
2024-7-1
|
| DOI |
10.1098/rsob.240140
|
| PMID |
39079673
|
| PMC |
PMC11288666
|
| MeSH |
Amino Acid Transport System X-AG* / genetics
Amino Acid Transport System X-AG* / metabolism
Animals
Glutamic Acid / metabolism
Mutation
Retina* / metabolism
Retinal Bipolar Cells / metabolism
Synaptic Transmission*
Zebrafish* / metabolism
Zebrafish Proteins* / genetics
Zebrafish Proteins* / metabolism
|
| Resource |
| Zebrafish |
Tg(zfSWS1-5.5A:EGFP)kj9
Tg(zfSWS2-3.5A:EGFP)kj11 / tkk008
Tg(RH2-2:GFP-PAC)kj4 / tkk004 |
