Fluorescence Sheds Light on DNA Damage, DNA Repair, and Mutations

Abstract

DNA damage can lead to carcinogenic mutations and toxicity that promotes diseases. Therefore, having rapid assays to quantify DNA damage, DNA repair, mutations, and cytotoxicity is broadly relevant to health. For example, DNA damage assays can be used to screen chemicals for genotoxicity, and knowledge about DNA repair capacity has applications in precision prevention and in personalized medicine. Furthermore, knowledge of mutation frequency has predictive power for downstream cancer, and assays for cytotoxicity can predict deleterious health effects. Tests for all of these purposes have been rendered faster and more effective via adoption of fluorescent readouts. Here, we provide an overview of established and emerging cell-based assays that exploit fluorescence for studies of DNA damage and its consequences.

Keywords: DNA damage; DNA repair; comet assay; fluorescence assays; γH2AX.

Figure 1:

Live-cell fluorescent based assays are enabling us to visualize and quantify DNA damage. (a) RaDR assay for visualizing mutations in vivo (b) γH2AX for analysis of DNA repair foci that are recruited at sites of DSBs (c) MicroColonyChip to analyze cell cytotoxicity by measuring the ability of cells to divide and form colonies in the presence of damaging DNA damaging agents (d) FM-HCR measures ability of cells to repair plasmid reporters carrying specific types of damage (e) CometChip assay measures DNA strand breaks.

Figure I:. DNA damage response pathway.

DNA damage can cause replication errors that can lead to an accumulation of mutations that promote carcinogenesis. Inefficient repair can also promote DNA damage-induced cell death, leading to increased toxicity and disease