Abstract

Vision in dim light depends on synapses between rods and rod bipolar cells (RBCs). Here, we find that these synapses exist in multiple configurations, in which single release sites of rods are apposed by one to three postsynaptic densities (PSDs). Single RBCs often form multiple PSDs with one rod; and neighboring RBCs share ~13% of their inputs. Rod-RBC synapses develop while ~7% of RBCs undergo programmed cell death (PCD). Although PCD is common throughout the nervous system, its influences on circuit development and function are not well understood. We generate mice in which ~53 and ~93% of RBCs, respectively, are removed during development. In these mice, dendrites of the remaining RBCs expand in graded fashion independent of light-evoked input. As RBC dendrites expand, they form fewer multi-PSD contacts with rods. Electrophysiological recordings indicate that this homeostatic co-regulation of neurite and synapse development preserves retinal function in dim light.

Details

Title
Homeostatic plasticity shapes the visual system’s first synapse
Author
Johnson, Robert E 1 ; Nai-Wen Tien 2 ; Shen, Ning 1 ; Pearson, James T 3 ; Soto, Florentina 1 ; Kerschensteiner, Daniel 4 

 Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, Saint Louis, MO, USA 
 Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, Saint Louis, MO, USA; Graduate Program in Neuroscience, Washington University School of Medicine, Saint Louis, MO, USA 
 Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, Saint Louis, MO, USA; Graduate Program in Developmental, Regenerative and Stem Cell Biology, Washington University School of Medicine, Saint Louis, MO, USA 
 Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, Saint Louis, MO, USA; Department of Neuroscience, Washington University School of Medicine, Saint Louis, MO, USA; Department of Biomedical Engineering, Washington University School of Medicine, Saint Louis, MO, USA; Hope Center for Neurological Disorders, Washington University School of Medicine, Saint Louis, MO, USA 
Pages
1-10
Publication year
2017
Publication date
Oct 2017
Publisher
Nature Publishing Group
e-ISSN
20411723
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
1958550666
Copyright
© 2017. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.