Using DNA looping to measure sequence dependent DNA elasticity

摘要

We are using tethered particle motion (TPM) microscopy to observe protein-mediated DNA looping in the lactoserepressor system in DNA constructs with varying AT / CG content. We use these data to determine the persistencelength of the DNA as a function of its sequence content and compare the data to direct micromechanical measurementswith constant-force axial optical tweezers. The data from the TPM experiments show a much smaller sequence effect onthe persistence length than the optical tweezers experiments.© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.