The main theme of our research is investigating the structure and dynamics of the nucleosome and chromatin to elucidate how their structure and dynamics contribute to the mechanisms of gene regulation. We approach our problems with single-molecule methods by controlling and observing how the individual molecules and complexes move and transform during their actions. Our methods include single-molecule fluorescence resonance energy transfer (smFRET), (co-)localization of fluorophores at an optical super-resolution, single photon correlation spectroscopy, and single-molecule force microscopy with optical tweezers.