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Title: Theory of chromatin organization maintained by active loop extrusion
The active loop extrusion hypothesis proposes that chromatin threads through the cohesin protein complex into progressively larger loops until reaching specific boundary elements. We build upon this hypothesis and develop an analytical theory for active loop extrusion which predicts that loop formation probability is a nonmonotonic function of loop length and describes chromatin contact probabilities. We validate our model with Monte Carlo and hybrid Molecular Dynamics–Monte Carlo simulations and demonstrate that our theory recapitulates experimental chromatin conformation capture data. Our results support active loop extrusion as a mechanism for chromatin organization and provide an analytical description of chromatin organization that may be used to specifically modify chromatin contact probabilities.  more » « less
Award ID(s):
1830957
NSF-PAR ID:
10421932
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
120
Issue:
23
ISSN:
0027-8424
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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