Real-time video microscopy for tethered particle motion assay.

Abstract

DNA folding is important in many different processes inside the cell. To measure DNA folding in real-time, we use a method called tethered particle motion (TPM). In this method, we observe the motion of particles tethered to the DNA rather than the DNA itself. Measuring the motion of particles allows us to draw conclusions about the length of the DNA and the state of the DNA folding pathway. Previously, we used ImageJ to track the motion of particles in prerecorded videos of TPM assays. This method posed an inconvenience: if there were any flaws in the video or the TPM assay, there would be no way of knowing that until after the sample had been prepared and recorded. To alleviate this issue, we created a LabVIEW program to observe the particle tracks in real-time. We envision that this new program will be useful in streamlining the data acquisition so we can study DNA folding.