Fluidification of Entangled Polymers by Loop Extrusion
arXiv:2401.17232 · doi:10.1103/PhysRevResearch.6.033160
Abstract
Loop extrusion is one of the main processes shaping chromosome organisation across the cell cycle, yet its role in regulating DNA entanglement and nucleoplasm viscoelasticity remains overlooked. We simulate entangled solutions of linear polymers under the action of generic Loop Extruding Factors (LEF) with a model that fully accounts for topological constraints and LEF-DNA uncrossability. We discover that extrusion drives the formation of bottle-brush-like structures which significantly lower the entanglement and effective viscosity of the system through an active fluidification mechanism. Interestingly, this fluidification displays an optimum at one LEF every 300-3000 basepairs. In marked contrast with entangled linear chains, the viscosity of extruded chains scales linearly with polymer length, yielding up to 1000-fold fluidification. Our results illuminate how loop extrusion contributes to actively modulate genome entanglement and viscoelasticity in vivo.
References in corpus (6)
- Molecular Dynamics Simulation Study of Nonconcatenated Ring Polymers in a Melt: I. Statics
- A Topologically Driven Glass in Ring Polymers
- Viscoelasticity and primitive path analysis of entangled polymer liquids: From f-actin to polyethylene
- Topological Linking Drives Anomalous Thickening of Ring Polymers In Weak Extensional Flows
- Synergy of Topoisomerase and Structural-Maintenance-of-Chromosomes Proteins Creates a Universal Pathway to Simplify Genome Topology
- Nonequilibrium Green-Kubo relations for hydrodynamic transport from an equilibrium-like fluctuation-response equality
Cited by in corpus (5)
- Motorized Chromosome Models of Mitosis
- Entropic organization of topologically modified ring polymers in spherical confinement
- Entropic alignment of topologically modified ring polymers in cylindrical confinement
- Yeast condensin acts as a transient intermolecular crosslinker in entangled DNA
- Fluctuations of driven probes reveal nonequilibrium transitions in complex fluids