Description
Age-related macular degeneration (AMD) is the leading cause of irreversible blindness in high-income countries. Although aging is the strongest known risk factor for AMD, the molecular mechanisms linking aging to disease pathogenesis remain poorly understood.
The Information Theory of Aging proposes that aging is driven, in part, by a progressive loss of epigenetic information, in which DNA double-strand breaks (DSBs) and their repair may erode the epigenetic landscape and disrupt cellular identity. This project aims to establish an in vitro retinal pigment epithelial cell model to investigate whether DNA damage-induced epigenetic changes contribute to AMD-relevant aging phenotypes.
Specifically, this work adapts the Inducible Changes to the Epigenome (ICE) system in ARPE-19 cells through stable expression of inducible I-PpoI, providing a controllable platform for inducing DSBs. To date, plasmid constructs encoding inducible I-PpoI have been generated, and CRISPR/Cas9-mediated knock-in has been used to establish stable ARPE-19 cell lines as a controllable DSB-induction model. Initial validation using γH2AX staining, SA-β-Gal staining, and qPCR analysis of aging-related markers indicates that I-PpoI activation induces nuclear DNA damage and promotes senescence-associated aging phenotypes in ARPE-19 cells.
Overall, this work establishes the foundation for a retinal epithelial model of DNA damage-induced cellular aging. Based on this established system, future work will apply single-cell RNA sequencing, ATAC-seq, and DNA methylation profiling, and integrate these data with AMD patient datasets to identify candidate molecular targets and pathways that link DSB-induced epigenetic aging to AMD-relevant cellular dysfunction. These candidates will then be functionally tested to determine whether targeting them can reverse aging-associated cellular phenotypes relevant to AMD.
Lay Abstract
Age-related macular degeneration (AMD) is a disease of the retina and a major cause of sight loss worldwide. Aging is the strongest known risk factor for AMD, but we still do not fully understand why retinal cells become more vulnerable over time. One possible explanation is that cells lose the instructions/molecular ‘memory’ that help maintain their identity and function known as loss of epigenetic information . This project aims to investigate whether DNA damage can trigger aging-like changes in RPE, a key cell type affected in AMD and essential for retinal health. We are building a laboratory model that allows controlled DNA damage to be introduced into these cells in order to mimic aspects of this aging process in retinal pigment epithelial cells. Early findings show that this approach activates DNA damage and reproduces features associated with cellular cells. Future work will combine these laboratory studies with large-scale patient genomic datasets to identify disease-relevant pathways and potential therapeutic targets. Understanding how DNA damage drives cellular aging may provide broader insights into the biological processes underlying many age-related diseases.
| Lay Title | How DNA Damage May Link Aging to Sight Loss in AMD |
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| Role | PhD Student |