Purchase this article with an account.
George Inana, Christopher Murat, Margaret McLaren; Casein Kinase 1 Epsilon Is Identified As A Potential Therapuetic Target For Dry AMD By A Multi-Pronged Gene Expression Approach. Invest. Ophthalmol. Vis. Sci. 2013;54(15):5016.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
To continue to analyze therapeutic targets for age-related macular degeneration (AMD) identified by a multi-pronged gene expression profiling approach combining gene expression in AMD, retinal pigment epithelium (RPE) phagocytosis, and cigarette smoking.
In vitro rod outer segment (ROS) phagocytosis assay of RPE, collection and classification of post-mortem human eyes, cigarette smoke exposure of mice, RNA isolation, gene expression profiling (total genome and custom CHANGE), northern hybridization, qRT-PCR, immunofluorescence microscopy, transgenic mouse construction.
Casein kinase 1 Epsilon (Ck1e), a critical regulator of circadian oscillations, was identified among genes changed in expression in AMD, ROS phagocytosis, and smoke exposure, a firmly established environmental factor for AMD. Ck1e significantly decreased and increased in expression, 5 and 15 hours, respectively, after addition of ROS to RPE in the in vitro assay, consistent with its involvement in phagocytosis. Consistent with a diurnal regulation, the expression of Ck1e peaked at 6pm and 3am in the retina and eyecup (EC), respectively. Expression of Ck1e was increased in AMD retina and EC in correlation to severity, peaking in grade 3 corresponding to severe atrophic AMD. A monkey model of dry AMD also showed increase in Ck1e expression in the retina. Exposure of mice to cigarette smoke increased Ck1e expression after 3 and 5 weeks in the EC and retina, respectively. The increase in Ck1e was confirmed in the ROS by immunofluorescence. Significantly, the smoke exposure shifted the diurnal peaks of Ck1e expression by 3 and 9 hours in the retina and EC, respectively. Conditional Ck1e over-expression transgenic mouse model was constructed, and preliminary result confirmed induced over-expression of Ck1e, setting the stage for phenotypic analysis of the model.
A multi-pronged approach based on gene expression in AMD, RPE phagocytosis, and smoking identified a potential candidate gene for dry AMD, Ck1e, that shows a significant correlation to dry AMD in humans and a monkey model and phase-shifts its diurnal peaks of expression after cigarette smoke exposure, possibly affecting critical circadian processes such as RPE phagocytosis of ROS. The conditional over-expression transgenic model should provide an excellent opportunity to investigate this candidate gene.
This PDF is available to Subscribers Only