PT  - JOURNAL ARTICLE
AU  - José Moya-Díaz
AU  - Ben James
AU  - Leon Lagnado
TI  - Modulation of the vesicle code transmitting the visual signal in the retina
AID  - 10.1101/2020.04.22.056119
DP  - 2020 Jan 01
TA  - bioRxiv
PG  - 2020.04.22.056119
4099  - http://biorxiv.org/content/early/2020/04/24/2020.04.22.056119.short
4100  - http://biorxiv.org/content/early/2020/04/24/2020.04.22.056119.full
AB  - Multivesicular release (MVR) allows retinal bipolar cells to transmit visual signals as changes in both the rate and amplitude of synaptic events. How do neuromodulators reguate this vesicle code? By imaging larval zebrafish, we find that the variability of calcium influx is a major source of synaptic noise. Dopamine increases synaptic gain up to 15-fold while Substance P reduces it 7-fold, both by acting on the presynaptic calcium transient to alter the distribution of amplitudes of multivesicular events. An increase in gain is accompanied by a decrease in the temporal precision of transmission and a reduction in the efficiency with which vesicles transfer visual information. The decrease in gain caused by Substance P was also associated with a shift in temporal filtering from band-pass to low-pass. This study demonstrates how neuromodulators act on the synaptic transformation of the visual signal to alter the way information is coded with vesicles.Competing Interest StatementThe authors have declared no competing interest.