Summary
This dissertation characterizes the transcription factor Math5 (Atoh7) as essential for retinal ganglion cell (RGC) differentiation in mice, and identifies a causative ATOH7 mutation in human optic nerve and vitreous diseases. Because RGCs include intrinsically photosensitive cells (ipRGCs) that drive circadian photoentrainment, insights into RGC development have downstream relevance for understanding individual variation in light sensitivity and non-visual light responses.
Key Findings
- Math5 knockout mice lack RGCs entirely, yet only ~10% of Math5-expressing progenitors adopt the RGC fate and only ~55% of RGCs are lineal descendants of Math5+ cells.
- Only 20–30% of the earliest-born retinal neuron cohort (which is ~80% RGCs) expresses Math5, suggesting a non-cell-autonomous role for Math5 in RGC specification.
- RGC marker expression (Math5, Brn3b, Isl1) was found in neurogenic cells prior to terminal mitosis during early development (<E14), indicating retinal fate determination is not strictly coupled to cell cycle exit.
- A missense mutation in the basic domain of human ATOH7 (p.N46H) was identified as causative for familial persistent hyperplastic primary vitreous (PHPV) and optic nerve hypoplasia/aplasia, confirmed by biochemical and functional assays.
Categories
Eye Health & Vision: This dissertation investigates the molecular biology of retinal ganglion cell development, which is directly relevant to understanding optic nerve disorders and retinal diseases.
The Science of Light: Retinal ganglion cells (RGCs), whose development depends on Math5/Atoh7, include ipRGCs — the photoreceptors responsible for non-visual light detection, circadian entrainment, and the pupillary light reflex.
Author(s)
L Prasov
Publication Year
2014
Number of Citations
1
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The Science of Light
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