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Updated: Jul 3, 2026

A Novel Light Damage Paradigm for Use in Retinal Regeneration Studies in Adult Zebrafish
Published on: October 24, 2013
[Activation of endoplasmic reticulum stress proteins in light-induced retinal degeneration]
Le-meng Wu1, Xiu-juan Guo, Mark Tso
1Department of Ophthalmology,Peking University Third Hospital, Peking University Eye Center, Beijing, China.
Objective:
To investigate the expression of endoplasmic reticulum stress proteins in photoreceptor apoptosis in light-induced retinal degeneration.
Methods:
Exposure to excessive levels of light induced photoreceptor apoptosis and had been previously used as a model for the study of retinal degeneration. Photoreceptor apoptosis was detected by terminal dUTP transferase nick end labeling (TUNEL). The protein expression levels of ER stress sensors including glucosejregulated protein-78 (GRP78/BiP), caspase-12, phospho-eukaryotic initiation factor 2alpha (eIF2alpha) and phospho- double-stranded RNA-activated protein kinase-like endoplasmic reticulum kinase (PERK) were examined by immunojfluorescence and Western blot analysis.
Results:
Following light exposure, the protein expression levels of GRP78/BiP, caspase-12, phospho-eIF2alpha and phospho-PERK were up-regulated in a time dependent manner. The up-regulation of these proteins coincided with or preceded the photoreceptor apoptosis. At the peak of their expression, they were mainly located in the photoreceptor inner segments and/or outer nuclear layers (ONL).
Conclusion:
Activation of endoplasmic reticulum stress proteins appears to play an important role in light-induced retinal degeneration. Therefore endoplasmic reticulum stress modulators could become a strong candidate for a therapeutic agent in treatment of these diseases.
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