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bioRxiv · 10.1101/2024.01.05.574343

A polymer physics view of peripheral chromatin: de Gennes' self-similar carpet

Erbas, A.·Sariyer, O. S.
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Abstract

Using scaling arguments to model peripheral chromatin localized near the inner surface of the nuclear envelope (NE) as a flexible polymer chain, we discuss the structural properties of the peripheral chromatin composed of alternating lamin-associated domains (LADs) and inter-LADs. Modeling the attraction of LADs to NE by de Gennes self-similar carpet, which treats the chromatin layer as a polymer fractal, explains two major experimental observations: (i) The high density of chromatin close to the nuclear periphery decays to a constant density as the distance to the periphery increases. (ii) Due to the decreasing mesh size towards the nuclear periphery, the chromatin carpet inside NE excludes molecules (via non-specific interactions) above a threshold size that depends on the distance from the nuclear periphery.

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Erbas, A., Sariyer, O. S.. 2024-01-05. A polymer physics view of peripheral chromatin: de Gennes' self-similar carpet. https://doi.org/10.1101/2024.01.05.574343

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