Speaker: Prof, Huan-Xiang Zhou, Department of Chemistry and Department of Physics, University of lllinois Chicago

Time: 10:00-11:30 a.m., Jun 26, 2024, GMT+8

Venue: Rm. CB213, CCME, PKU

Abstract: 

Biomolecular condensates, formed through liquid-liquid phase separation, mediate crucial cellular functions and are linked with neurodegeneration and cancer, To reach a fundamental understanding of their phase equilibrium and material properties, we have integrated experimental techniques including optical tweezers and fluorescence imaging with atomistic simulations and modeling to characterize biomolecular condensates. Our experiments reveal enormous differences among peptides with different amino-acid compositions in phase equilibrium and material properties, including a 400-fold range in the threshold concentration for phase separation and a 4000-fold range in viscosity. Our all-atom molecular dynamics simulations provide physical explanations of these results. Similarly, atomistic simulations show that ATP drives the phase separation of basic disordered proteins and endows the resulting condensates with unusual material properties including extreme shear thinning, by bridging between protein chains, In studies based on atomistic modeling, we have identified a single amino-acid substitution (S130W) in the eye lens proteins y-crystallins responsible for a large increase in the critical temperature for phase separation and uncovered how pH regulates the phase separation of polySUMO and polySIM.
an atomistic phase.

Source: Center for Quantitative Biology