Tae-Hee Lee

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. Studying the dynamics of biological macromolecular complexes is essential to understanding their behavior and function. Studying dynamically and asynchronously transforming complexes through a multi-step process requires a capability of monitoring sub-population dynamics inaccessible from ensemble-averaging approaches. Single-molecule spectroscopy and microscopy provide efficient ways to address these problems. My research program focuses on the structure and dynamics of the nucleosome, chromatosome, nucleosome arrays, and various enzymes acting on the nucleosome such as chromatin remodelers and RNA polymerase II. We investigate these complexes to understand what roles they play in regulating the genome transactions at the nucleosome and the nucleosome-array levels. My research program is very much interdisciplinary across physical chemistry, analytical chemistry, biochemistry, molecular/structural/cellular biology, and nanoscale science/engineering. Analytical, Biological, Physical, Spectroscopy