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Title: Symmetry-based classification of forces driving chromatin dynamics
Chromatin – the functional form of DNA in the cell – exists in the form of a polymer immersed in a nucleoplasmic fluid inside the cell nucleus. Both chromatin and nucleoplasm are subject to active forces resulting from local biological processes. This activity leads to non-equilibrium phenomena, affecting chromatin organization and dynamics, yet the underlying physics is far from understood. Here, we expand upon a previously developed two-fluid model of chromatin and nucleoplasm by considering three types of activity in the form of force dipoles – two with both forces of the dipole acting on the same fluid (either polymer or nucleoplasm) and a third, with two forces pushing chromatin and solvent in opposite directions. We find that this latter type results in the most significant flows, dominating over most length scales of interest. Due to the friction between the fluids and their viscosity, we observe emergent screening length scales in the active flows of this system. We predict that the presence of different activity types and their relative strengths can be inferred from observing the power spectra of hydrodynamic fluctuations in the chromatin and the nucleoplasm.  more » « less
Award ID(s):
1762506 1554880 2153432 2210541
NSF-PAR ID:
10377012
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Soft Matter
ISSN:
1744-683X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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