Circuit mechanisms underlying embryonic retinal waves
- University of California, Berkeley, United States
- Vanderbilt University, United States
Abstract
Spontaneous activity is a hallmark of developing neural systems. In the retina, spontaneous activity comes in the form of retinal waves, comprised of three stages persisting from embryonic day 16 (E16) to eye opening at postnatal day 14 (P14). Though postnatal retinal waves have been well characterized, little is known about the spatiotemporal properties or the mechanisms mediating embryonic retinal waves, designated Stage 1 waves. Using a custom-built macroscope to record spontaneous calcium transients from whole embryonic retinas, we show that Stage 1 waves are initiated at several locations across the retina and propagate across a broad range of areas. Blocking gap junctions reduced the frequency and size of Stage 1 waves, nearly abolishing them. Global blockade of nAChRs similarly nearly abolished Stage 1 waves. Thus, Stage 1 waves are mediated by a complex circuitry involving subtypes of nAChRs and gap junctions. Stage 1 waves in mice lacking the β2 subunit of the nAChRs (β2-nAChR-KO) persisted with altered propagation properties and were abolished by a gap junction blocker. To assay the impact of Stage 1 waves on retinal development, we compared the spatial distribution of a subtype of retinal ganglion cells, intrinsically photosensitive retinal ganglion cells (ipRGCs), which undergo a significant amount of cell death, in WT and β2-nAChR-KO mice. We found that the developmental decrease of ipRGC density is preserved between WT and β2-nAChR-KO mice, indicating that processes regulating ipRGC distribution are not influenced by spontaneous activity.
Data availability
We have uploaded the raw data for Figure 5 on Dryad.All other raw imaging data and images are available upon request as they are too large to update to on Dryad. They are residing on our lab server and can be transferred via ftp.Figures 1-4. These data are based on movies acquired from live imaging of activity using a macroscope or a 2-photon scanning microscope.Figure 1: 50 gigabytesFigures 2/4: 180 gigabytesFigure 3: 233 gigabytesFigure 5: These are high resolution fluorescence images acquired from microscope at various z-plane focus planes. 7 gigabytes total. (on Dryad)All code and software are available in this gitHub location: https://github.com/FellerLabCodeShare/Embryonic-Retinal-WavesInstructions on how to build a macroscope available at this gitHub location: https://github.com/Llamero/DIY_Epifluorescence_Macroscope
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Circuit mechanisms underlying embryonic retinal wavesDryad Digital Repository, doi:10.5061/dryad.h18931zr2.
Article and author information
Author details
Funding
National Eye Institute (RO1EY013528,RO1EY019498,P30EY003176)
- Christiane Voufo
National Eye Institute (K99EY030909)
- Alexandre Tiriac
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication
Ethics
Animal experimentation: All animal procedures were approved by the UC Berkeley Institutional Animal Care and Use Committee and conformed to the NIH Guide for the Care and Use of Laboratory Animals, the Public Health Service Policy, and the SFN Policy on the Use of Animals in Neuroscience Research.
Copyright
© 2023, Voufo 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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Circuit mechanisms underlying embryonic retinal waves
eLife 12:e81983.
https://doi.org/10.7554/eLife.81983
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