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Chromatin Dynamics are Highly Subdiffusive Across Seven Orders of Magnitude
Matteo Mazzocca1,2,3,4, Domenic N Narducci1,2,3,4, Simon Grosse-Holz5,6
1Department of Biological Engineering, Massachusetts Institute of Technology; Cambridge, MA 02139, USA.
Biorxiv : the Preprint Server for Biology
|June 4, 2025
Summary
Chromatin dynamics exhibit strong subdiffusion, impacting biological processes. Search times for DNA loci are short at close distances but extremely long for distant ones.
Area of Science:
- Molecular Biology
- Cell Biology
- Biophysics
Background:
- Chromatin dynamics are crucial for DNA repair and gene regulation.
- Previous studies reported variable subdiffusion due to technical limitations.
Purpose of the Study:
- To precisely measure chromatin dynamics across a wide timescale.
- To investigate factors influencing chromatin movement and search efficiency.
Main Methods:
- Integration of MINFLUX single particle tracking with traditional methods.
- Tracking chromatin dynamics in human and mouse cells over seven orders of magnitude in time.
Main Results:
- Observed strongly subdiffusive chromatin dynamics (α ~ 0.3).
- Dynamics showed mild sensitivity to transcription, histone acetylation, and topoisomerase II.
- Loop extrusion significantly constrained chromatin movement.
Conclusions:
- Subdiffusion limits the efficiency of long-range DNA locus interactions.
- Findings impact understanding of enhancer-promoter communication and DNA repair mechanisms.
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