The cell adhesion molecule Sdk1 shapes assembly of a retinal circuit that detects localized edges
- McGill University, Canada
Abstract
Nearly 50 different mouse retinal ganglion cell (RGC) types sample the visual scene for distinct features. RGC feature selectivity arises from their synapses with a specific subset of amacrine (AC) and bipolar cell (BC) types, but how RGC dendrites arborize and collect input from these specific subsets remains poorly understood. Here we examine the hypothesis that RGCs employ molecular recognition systems to meet this challenge. By combining calcium imaging and type-specific histological stains we define a family of circuits that express the recognition molecule Sidekick 1 (Sdk1) which include a novel RGC type (S1-RGC) that responds to local edges. Genetic and physiological studies revealed that Sdk1 loss selectively disrupts S1-RGC visual responses which result from a loss of excitatory and inhibitory inputs and selective dendritic deficits on this neuron. We conclude that Sdk1 shapes dendrite growth and wiring to help S1-RGCs become feature selective.
Data availability
Sample registration fields, registration code, and GCaMP6f datasets are available at Dryad (https://doi.org/10.5061/dryad.4xgxd2593).
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Data From: The cell adhesion molecule Sdk1 shapes assembly of a retinal circuit that detects localized edgesDryad Digital Repository, doi:10.5061/dryad.4xgxd2593.
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Study: Mouse retinal ganglion cell adult atlas and optic nerve crush time seriesBroad Institute Single Cell Portal.
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Study: Retinal Bipolar Neuron Drop-seqBroad Institute Single Cell Portal.
Article and author information
Author details
Arjun Krishnaswamy
Funding
Canadian Institutes of Health Research (project grant)
- Arjun Krishnaswamy
Natural Sciences and Engineering Research Council of Canada (discovery grant)
- Arjun Krishnaswamy
Canadian Institutes of Health Research (Graduate Fellowship)
- Pierre-Luc Rochon
Fonds de Recherche du Québec - Santé (Graduate Fellowship)
- Aline Giselle Rangel Olguin
Consejo Nacional de Ciencia y Tecnología (Graduate Fellowship)
- Aline Giselle Rangel Olguin
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: Animals were used in accordance with the rules and regulations established by the Canadian Council on Animal Care and protocol (2017-7889) was approved by the Animal Care Committee at McGill University
Copyright
© 2021, Rochon et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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The cell adhesion molecule Sdk1 shapes assembly of a retinal circuit that detects localized edges
eLife 10:e70870.
https://doi.org/10.7554/eLife.70870
Further reading
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