Current Research Interests.

Physical Principles underlying Molecular Motors

Living matter in action, at the smallest length scale epitomized by biological motors, operates in nonequilibrium steady states (NESS). In NESS, the detailed balance is broken such that nonvanishing energy and material currents are constantly fed and flow out of the system.
Together with the microscopic underpinnings underlying the functions of individual motors, we are interested in quantifying how energy, information, and material balance in biological systems contributes to the emergence of cellular organizations.

Structure, dynamics, and function of human chromosomes
The packaging of chromosomes, giant chain molecules made of hundreds of megabase-long DNA, into a small volume is truly remarkable. Recent advances in Hi-C and imaging technique have ushered in a new era of research on genome organization, which is bound to reveal the origin of the cell type-dependent gene expression in due course. Despite these advances, our understanding of the dynamics of chromosome/genome at varying scales of space and time is still in its infancy. Seemingly daunting problem at a first glance, polymer physics idea and molecular simulations provide glimpses into the link between the spatiotemporal dynamics of chromosome and its characteristic chain organization. We try to explore the effect of physical/energetic constraints in chromosome architecture on the dynamics, and learn the physical basis of gene expression.    

Origin of heterogeneous and slow dynamics in biomolecular systems

Single molecule time trajectories of biomolecules provide glimpses into complex folding landscapes that are difficult to visualize using conventional ensemble measurements. Recent experiments using single molecule measurements and theoretical analyses have highlighted dynamic disorder in certain classes of biomolecules, whose dynamic pattern of conformational transitions is affected by slower transitions between hidden internal states. In recent years, we have not only articulated the existence of dynamical heterogeneity in Holliday junction dynamics (Nature Chem. (2012)) and in kinesin function (Traffic (2017)), but also developed theories to extract the extent of heterogeneity using a single molecule force spectroscopy (Phys. Rev. Lett. (2014), PNAS (2017)). The issues of properly analyzing dynamical heterogeneity in the dynamics of biomolecules and deciphering microscopic underpinnings of the heterogeneity are one of the main research themes of the group.  

Allostery in biomolecules

A
llostery refers to a long-range communication between two remote sites in biomolceuls. Key question concerning allostery would be: For a given conformational ensemble of a protein, which are the key residue for allostery? What are the allosteric signaling pathways? Investigating a variety of structural ensemble of protein with and without cognate ligand we aim to decipher the physical basis of allostery. 

Contact Information : Changbong Hyeon, Professor, School of Computational Sciences, Korea Institute for Advanced Study, Seoul 02455, Korea
+82-2-958-3810 (tel)

© 2010 KIAS Theoretical and Computational Biophysics Group