Tae Hun Kim, PhD

Human cells store approximately 3 billion base pairs of DNA in the nucleus, which would be roughly 2 meters long if fully extended. However, the DNA is contained within the nucleus, which is only around 6 μm in diameter, due to compaction by packaging it as chromatin. Chromatin consists of nucleosomes, the basic structural unit of DNA packaging, and a series of nucleosomes connected by linker DNAs constitute chromatins. Regulatory proteins can reorganize chromatin structures so that specific genes are transcribed in a spatiotemporal-specific manner. 

DNA damage repair and transcription both require large reorganizations of nucleosomes and chromatin structures by histone modifications and chromatin remodelers, which are tightly controlled by a myriad of mechanisms in a dynamic manner. When these processes are disrupted by mutations, it can lead to diseases like cancer and neurological disorders. Our laboratory investigates how transcription factors, DNA damage response proteins, and epigenetic modifications induce changes in the structure, dynamics, and interactions of chromatin. We are also interested in studying how drugs or lead compounds bind proteins involved in these key processes. Lastly, our laboratory investigates how "liquid-liquid phase separation" can modulate transcription and DNA damage repair. To do this, we use multidisciplinary approaches, including biophysical tools (NMR and cryo-EM), molecular biology, protein chemistry, and fluorescence microscopy.