Department of Biology, Johns Hopkins University, Baltimore, United States
Michael B Thomsen
Department of Biology, Johns Hopkins University, Baltimore, United States
Jennifer L Ecker
Department of Biology, Johns Hopkins University, Baltimore, United States
Gideon S Loevinsohn
Department of Neuroscience, Brown University, Providence, United States
Cassandra VanDunk
Department of Anatomy and Neurobiology, Washington University, St. Louis, United States; Department of Neurobiology, Northwestern University, Evanston, United States
Daniel C Vicarel
Department of Biology, Program in Integrated Bioscience, The University of Akron, Akron, United States
Adele Tufford
Cellular Neurobiology Research Unit, Institut De Recherches Cliniques De Montréal, Montreal, Canada
Shijun Weng
Department of Neuroscience, Brown University, Providence, United States
Paul A Gray
Department of Anatomy and Neurobiology, Washington University, St. Louis, United States; Indigo Agriculture, Charlestown, United States
Michel Cayouette
Cellular Neurobiology Research Unit, Institut De Recherches Cliniques De Montréal, Montreal, Canada; Faculty of Medicine, Université De Montréal, Montreal, Canada
Erik D Herzog
Department of Biology, Washington University, St. Louis, United States
Haiqing Zhao
Department of Biology, Johns Hopkins University, Baltimore, United States
David M Berson
Department of Neuroscience, Brown University, Providence, United States
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.
