Assembling Protein-Mediated DNA Bridges and Measuring Interaction Forces

_{KEYWORDS: Optical Tweezers; NanoTracker; Fluorescence Microscopy; Optical Integration; Optical Trap; Force Measurements; DNA; DNA Bridges; Nanomanipulation}

The NanoTracker Optical Tweezers (OT) setup delivers the ground-breaking capabilities researchers need to unravel fundamental processes taking place in living cells. This system enables the non-invasive trapping and manipulation of biological samples in both in vitro and in vivo studies. It is a powerful research tool for investigating real-time interactions in living cells, single molecules, viruses, and bacteria with nanometer precision and femtonewton resolution.

This application note outlines how optical tweezers can be successfully applied to study DNA damage, repair mechanisms, and protein-mediated DNA bridges. We demonstrate that interaction forces between individual molecules, the strength of the intermolecular connection, and the rupture force necessary to break protein-mediated DNA bridges apart can be precisely measured and quantified.

Readers can expect to learn about:

• The advantages of non-invasive trapping and manipulation of biological samples;
• How dual and multi-trap OT can be combined with fluorescence microscopy to assemble and visualize complex single-molecule assays and study their function in vitro; and
• How to use the NanoTracker to manipulate, trigger, and probe DNA-DNA, DNA-protein, and protein-protein interactions.