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Abstract Condensation by phase separation has recently emerged as a mechanism underlying many nuclear compartments essential for cellular functions. Nuclear condensates enrich nucleic acids and proteins, localize to specific genomic regions, and often promote gene expression. How diverse properties of nuclear condensates are shaped by gene organization and activity is poorly understood. Here, we develop a physics-based model to interrogate how spatially-varying transcription activity impacts condensate properties and dynamics. Our model predicts that spatial clustering of active genes can enable precise localization and de novo nucleation of condensates. Strong clustering and high activity results in aspherical condensate morphologies. Condensates can flow towards distant gene clusters and competition between multiple clusters lead to stretched morphologies and activity-dependent repositioning. Overall, our model predicts and recapitulates morphological and dynamical features of diverse nuclear condensates and offers a unified mechanistic framework to study the interplay between non-equilibrium processes, spatially-varying transcription, and multicomponent condensates in cell biology.
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Extracellular pectin-RALF phase separation mediates FERONIA global signaling function
In deciphering the global signaling capacity of FERONIA receptor kinase, Liu, Yeh, et al. discovered an extracellular phase separation process driven by FERONIA peptide ligand RALF-cell wall polysaccharide pectin interaction, which leads to cognate and non-cognate receptor clustering and promiscuous endocytosis as a coping mechanism in response to environmental stressors. Highlights Cell surface pectin-RALF1 phase separation recruits FERONIA-LLG1 into condensates RALF induces FERONIA-LLG1-dependent promiscuous receptor clustering and endocytosis RALF1-pectin molecular condensates function as surface sensors for stress signals FERONIA-LLG1-mediated global endocytosis ensures plant resilience under stress
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- PAR ID:
- 10509451
- Publisher / Repository:
- Cell Press
- Date Published:
- Journal Name:
- Cell
- Volume:
- 187
- Issue:
- 2
- ISSN:
- 0092-8674
- Page Range / eLocation ID:
- 312 to 330.e22
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1016/j.cell.2023.11.038
