Static Chromatin from Liquid Condensates

Date and time: Thursday, January 14, 2021 - 4:00 p.m. to 5:30 p.m.

Speaker: Sy Redding, University of California-San Francisco

HP1-mediated Heterochromatin forms positionally and mechanically stable genomic domains in vivo, yet HP1 proteins are incredibly dynamic. We show that the asymmetry in size and dynamics between DNA and HP1 results in viscoelastic, phase-separated condensates in vitro, where HP1 exhibits many of the behaviors of dynamic liquids, while compacted DNA molecules are constrained to local territories. Furthermore, we demonstrate that HP1-DNA condensates resist and remember large forces at the mesoscale while being susceptible to competition and disruption at the molecular scale. Finally, we show how these features allow HP1 to form epigenetically distinct chromatin domains in vitro in agreement with its role in organizing chromatin in the nucleus.

Zoom Link for Seminar:
Meeting ID: 937 4253 5825 Passcode: 942559