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Mechanical Frustration of Phase Separation in the Cell Nucleus by Chromatin.

ABSTRACT: Liquid-liquid phase separation is a fundamental mechanism underlying subcellular organization. Motivated by the striking observation that optogenetically generated droplets in the nucleus display suppressed coarsening dynamics, we study the impact of chromatin mechanics on droplet phase separation. We combine theory and simulation to show that cross-linked chromatin can mechanically suppress droplets' coalescence and ripening, as well as quantitatively control their number, size, and placement. Our results highlight the role of the subcellular mechanical environment on condensate regulation.

SUBMITTER: Zhang Y

PROVIDER: S-EPMC8604804 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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Mechanical Frustration of Phase Separation in the Cell Nucleus by Chromatin.

Zhang Yaojun Y Lee Daniel S W DSW Meir Yigal Y Brangwynne Clifford P CP Wingreen Ned S NS

Physical review letters 20210601 25

Liquid-liquid phase separation is a fundamental mechanism underlying subcellular organization. Motivated by the striking observation that optogenetically generated droplets in the nucleus display suppressed coarsening dynamics, we study the impact of chromatin mechanics on droplet phase separation. We combine theory and simulation to show that cross-linked chromatin can mechanically suppress droplets' coalescence and ripening, as well as quantitatively control their number, size, and placement. ...[more]

PMID: 34241518

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