Genomic DNA within the cell nucleus is packaged, together with histones and other functional proteins, into chromatin. We are interested in understanding its organization within chromatin, as well as the topological constraints imposed upon it within the higher-order arrangement imposed by nonhistone proteins, such as CTCF. These studies are important as they will allow us to better understand the structure of both the ‘open’ and condensed chromatin fiber in vivo. Furthermore, as chromatin plays an essential role in processes such as DNA transcription, replication, repair, and recombination, its organization is fundamental to understanding the finer details of these processes.
Macromolecular interactions define most biological processes. We utilize thermodynamic and hydrodynamic methods to characterize biological assemblies in terms of their shape, stoichiometry, and affinity of interaction. These studies complement current biochemical, structural, and physiological investigations within the National Institute of Diabetes and Digestive and Kidney Diseases. They further provide a platform for the development and improvement of current biophysical and thermodynamic methodologies, particularly analytical ultracentrifugation.