Freely orbiting magnetic tweezers to directly monitor changes in the twist of nucleic acids
Citations Over TimeTop 10% of 2011 papers
Abstract
The double-stranded nature of DNA links its replication, transcription and repair to rotational motion and torsional strain. Magnetic tweezers (MT) are a powerful single-molecule technique to apply both forces and torques to individual DNA or RNA molecules. However, conventional MT do not track rotational motion directly and constrain the free rotation of the nucleic acid tether. Here we present freely orbiting MT (FOMT) that allow the measurement of equilibrium fluctuations and changes in the twist of tethered nucleic acid molecules. Using a precisely aligned vertically oriented magnetic field, FOMT enable tracking of the rotation angle from straight forward (x,y)-position tracking and permits the application of calibrated stretching forces, without biasing the tether's free rotation. We utilize FOMT to measure the force-dependent torsional stiffness of DNA from equilibrium rotational fluctuations and to follow the assembly of recombination protein A filaments on DNA.
Related Papers
- → Single-molecule force spectroscopy: optical tweezers, magnetic tweezers and atomic force microscopy(2008)2,352 cited
- → Trapping and sorting of nanoparticles by bowtie-nanohole plasmonic tweezers(2023)3 cited
- → Particles sorting in micro-channel using magnetic tweezers and optical tweezers(2014)
- Muscle-powered nano mechanical system assembled by optical tweezers(2009)
- → Comparison between radiation forces upon nanoparticles in continuous laser tweezers and in pulsed laser tweezers(2010)