Detection of Abasic Site on Single DNA Molecules using Fluorescence Microscopy

摘要

A new method was developed to allow directly visualize damage sites on the individual DNA molecules. Fluorescence in situ hybridization (FISH) on extended DNA fibers was modified to allow a detection of single abasic site on DNA fibers. Biotinylated aldehyde-reactive-probe (ARP) and fluorochrome conjugated streptavidin were employed to the specific labeling of abasic sites. The emitted light by a single biotin-streptavidin complex was calibrated. The number of abasic site on the DNA molecule was estimated by counting each DNA-fluorochrome complex, The present study visualized damage of single DNA molecules.