Abstract
We developed a new microfluidic device and an optically driven microtool to control higher-order structure of individual intact chromatin fibers. The device is able to extract chromatin fibers from single cells with burst method, to conduct immunofluorescent staining against them, to stretch them by the flow in the device under a fluorescence microscope. To visualize chromatin fibers, recombined fission yeast, S. Pombe, was employed which expresses histone H3-RFP and CENP-A-GFP. To control higher order structure of chromatin fibers which stability depends on the electrostatic interaction between DNA and histone proteins, salt concentration was increased intermittently in the microfluidic device. It was observed that chromatin fibers were elongated and their fluorescence of histone H3-RFP decreased as the salt concentration was increased. This indicates destruction of higher order structure of chromatin and dissociation of histone proteins.
