A subset of ipRGCs regulates both maturation of the circadian clock and segregation of retinogeniculate projections in mice
- Johns Hopkins University, United States
- University of Akron, United States
- National Institute of Mental Health, National Institute of Health, United States
- Brown University, United States
- Washington University, United States
- Insistut de Recherches Cliniques de Montréal, Canada
Abstract
The visual system consists of two major subsystems, image-forming circuits that drive conscious vision and non-image-forming circuits for behaviors such as circadian photoentrainment. While historically considered non-overlapping, recent evidence has uncovered crosstalk between these subsystems. Here we investigated shared developmental mechanisms. We revealed an unprecedented role for light in the maturation of the circadian clock and discovered that intrinsically photosensitive retinal ganglion cells (ipRGCs) are critical for this refinement process. In addition, ipRGCs regulate retinal waves independent of light, and developmental ablation of a subset of ipRGCs disrupts eye-specific segregation of retinogeniculate projections. Specifically, a subset of ipRGCs, comprising ~200 cells and which project intraretinally and to circadian centers in the brain, are sufficient to mediate both of these developmental processes. Thus, this subset of ipRGCs constitute a shared node in the neural networks that mediate light-dependent maturation of the circadian clock and light-independent refinement of retinogeniculate projections.
Article and author information
Author details
William Thomas Keenan
Funding
National Institute of General Medical Sciences (GM076430)
- Samer Hattar
National Eye Institute (F32-EY20108)
- Jordan M Renna
National Eye Institute (R15EY026255)
- Jordan M Renna
Canadian Institutes of Health Research (MOP-77570)
- Michel Cayouette
National Eye Institute (R01-EY019053)
- Samer Hattar
David and Lucile Packard Foundation
- Samer Hattar
Alfred P. Sloan Foundation
- Samer Hattar
Johns Hopkins University
- Samer Hattar
National Eye Institute (R01-EY017137)
- David M Berson
National Institute on Deafness and Other Communication Disorders (DC007395)
- Haiqing Zhao
National Institute of General Medical Sciences (R01-GM104991)
- Erik D Herzog
National Heart, Lung, and Blood Institute (R01-HL089742)
- Paul A Gray
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 housed and treated in accordance with NIH and IACUC guidelines, and used protocols approved by the Johns Hopkins University and Brown University Animal Care and Use Committees (Protocol numbers MO16A212 and 1010040).
Copyright
© 2017, Chew 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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A subset of ipRGCs regulates both maturation of the circadian clock and segregation of retinogeniculate projections in mice
eLife 6:e22861.
https://doi.org/10.7554/eLife.22861
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