Gap junctions fine-tune ganglion cell signals to equalize response kinetics within a given electrically coupled array
Gergely Szarka,
Alma Ganczer,
Márton Balogh,
Ádám Jonatán Tengölics,
Anett Futácsi,
Garrett Kenyon,
Feng Pan,
Tamás Kovács-Öller,
Béla Völgyi
Affiliations
Gergely Szarka
University of Pécs, Szentágothai Research Centre, Pécs, Hungary; University of Pécs, Department of Neurobiology, Pécs, Hungary; MTA-PTE NAP 2 Retinal Electrical Synapses Research Group, Pécs, Hungary; Center for Neuroscience, University of Pécs, Pécs, Hungary; SzKK Imaging Core Facility, Szentágothai Research Centre, University of Pécs, Pécs, Hungary
Alma Ganczer
University of Pécs, Szentágothai Research Centre, Pécs, Hungary; University of Pécs, Department of Neurobiology, Pécs, Hungary; MTA-PTE NAP 2 Retinal Electrical Synapses Research Group, Pécs, Hungary; Center for Neuroscience, University of Pécs, Pécs, Hungary
Márton Balogh
University of Pécs, Szentágothai Research Centre, Pécs, Hungary; University of Pécs, Department of Neurobiology, Pécs, Hungary; MTA-PTE NAP 2 Retinal Electrical Synapses Research Group, Pécs, Hungary; Center for Neuroscience, University of Pécs, Pécs, Hungary
Ádám Jonatán Tengölics
University of Pécs, Szentágothai Research Centre, Pécs, Hungary; University of Pécs, Department of Neurobiology, Pécs, Hungary; MTA-PTE NAP 2 Retinal Electrical Synapses Research Group, Pécs, Hungary; Center for Neuroscience, University of Pécs, Pécs, Hungary
Anett Futácsi
University of Pécs, Szentágothai Research Centre, Pécs, Hungary; MTA-PTE NAP 2 Retinal Electrical Synapses Research Group, Pécs, Hungary; Center for Neuroscience, University of Pécs, Pécs, Hungary; SzKK Imaging Core Facility, Szentágothai Research Centre, University of Pécs, Pécs, Hungary
Garrett Kenyon
Los Alamos National Laboratory, Los Alamos, NM, USA
Feng Pan
The Hong Kong Polytechnic University, Hong Kong, China
Tamás Kovács-Öller
University of Pécs, Szentágothai Research Centre, Pécs, Hungary; University of Pécs, Department of Neurobiology, Pécs, Hungary; MTA-PTE NAP 2 Retinal Electrical Synapses Research Group, Pécs, Hungary; Center for Neuroscience, University of Pécs, Pécs, Hungary; SzKK Imaging Core Facility, Szentágothai Research Centre, University of Pécs, Pécs, Hungary
Béla Völgyi
University of Pécs, Szentágothai Research Centre, Pécs, Hungary; University of Pécs, Department of Neurobiology, Pécs, Hungary; MTA-PTE NAP 2 Retinal Electrical Synapses Research Group, Pécs, Hungary; Center for Neuroscience, University of Pécs, Pécs, Hungary; Corresponding author
Summary: Retinal ganglion cells (RGCs) summate inputs and forward a spike train code to the brain in the form of either maintained spiking (sustained) or a quickly decaying brief spike burst (transient). We report diverse response transience values across the RGC population and, contrary to the conventional transient/sustained scheme, responses with intermediary characteristics are the most abundant. Pharmacological tests showed that besides GABAergic inhibition, gap junction (GJ)–mediated excitation also plays a pivotal role in shaping response transience and thus visual coding. More precisely GJs connecting RGCs to nearby amacrine and RGCs play a defining role in the process. These GJs equalize kinetic features, including the response transience of transient OFF alpha (tOFFα) RGCs across a coupled array. We propose that GJs in other coupled neuron ensembles in the brain are also critical in the harmonization of response kinetics to enhance the population code and suit a corresponding task.
