PUBLICATION
Phagosomal and mitochondrial alterations in RPE may contribute to KCNJ13 retinopathy
- Authors
- Toms, M., Burgoyne, T., Tracey-White, D., Richardson, R., Dubis, A.M., Webster, A.R., Futter, C., Moosajee, M.
- ID
- ZDB-PUB-190309-2
- Date
- 2019
- Source
- Scientific Reports 9: 3793 (Journal)
- Registered Authors
- Keywords
- none
- MeSH Terms
-
- Animals
- Melanosomes/genetics
- Melanosomes/metabolism
- Mitochondria/genetics
- Mitochondria/metabolism*
- Mitochondria/pathology
- Mutation
- Phagosomes/pathology*
- Potassium Channels, Inwardly Rectifying/genetics*
- Potassium Channels, Inwardly Rectifying/metabolism
- Retina/diagnostic imaging
- Retina/pathology
- Retina/ultrastructure
- Retinal Degeneration/diagnostic imaging*
- Retinal Degeneration/genetics*
- Retinal Degeneration/pathology
- Retinal Pigment Epithelium/pathology*
- Tomography, Optical Coherence
- Zebrafish/genetics
- PubMed
- 30846767 Full text @ Sci. Rep.
Citation
Toms, M., Burgoyne, T., Tracey-White, D., Richardson, R., Dubis, A.M., Webster, A.R., Futter, C., Moosajee, M. (2019) Phagosomal and mitochondrial alterations in RPE may contribute to KCNJ13 retinopathy. Scientific Reports. 9:3793.
Abstract
Mutations in KCNJ13 are associated with two retinal disorders; Leber congenital amaurosis (LCA) and snowflake vitreoretinal degeneration (SVD). We examined the retina of kcnj13 mutant zebrafish (obelixtd15, c.502T > C p.[Phe168Leu]) to provide new insights into the pathophysiology underlying these conditions. Detailed phenotyping of obelixtd15 fish revealed a late onset retinal degeneration at 12 months. Electron microscopy of the obelixtd15 retinal pigment epithelium (RPE) uncovered reduced phagosome clearance and increased mitochondrial number and size prior any signs of retinal degeneration. Melanosome distribution was also affected in dark-adapted 12-month obelixtd15 fish. At 6 and 12 months, ATP levels were found to be reduced along with increased expression of glial fibrillary acidic protein and heat shock protein 60. Quantitative RT-PCR of polg2, fis1, opa1, sod1/2 and bcl2a from isolated retina showed expression changes consistent with altered mitochondrial activity and retinal stress. We propose that the retinal disease in this model is primarily a failure of phagosome physiology with a secondary mitochondrial dysfunction. Our findings suggest that alterations in the RPE and photoreceptor cellular organelles may contribute to KCNJ13-related retinal degeneration and provide a therapeutic target.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping