Enrichment of Dynamic Chromosomal Crosslinks Drive Phase Separation of the Nucleolus

Abstract

Regions of highly repetitive DNA, such as those found in the nucleolus, show a self-organization that is marked by spatial segregation and frequent self-interaction. The mechanisms that underlie the sequestration of these sub-domains are largely unknown. Using a stochastic, bead-spring representation of chromatin in budding yeast, we find enrichment of protein-mediated, dynamic chromosomal cross-links recapitulates the segregation, morphology and self-interaction of the nucleolus. Rates and enrichment of dynamic crosslinking have profound consequences on domain morphology. Our model demonstrates the nucleolus is phase separated from other chromatin in the nucleus and predicts that multiple rDNA loci will form a single nucleolus independent of their location within the genome. Fluorescent labeling of budding yeast nucleoli with CDC14-GFP revealed that a split rDNA locus indeed forms a single nucleolus. We propose that nuclear subdomains,such as the nucleolus, result from phase separations within the nucleus, which are driven by the enrichment of protein-mediated, dynamic chromosomal crosslinks.

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Document Details

Document Type
Technical Report
Publication Date
Aug 22, 2017
Accession Number
AD1069028

Entities

People

  • Alyssa York
  • Caitlin Hult
  • David Adalsteinsson
  • Diana Cook
  • Elaine Yeh
  • Josh Lawrimore
  • Kerry Bloom
  • Maggie Bennett
  • Mark G. Forest
  • Paula A. Vasquez

Organizations

  • University of North Carolina at Chapel Hill

Tags

DTIC Thesaurus Topics

  • Cell Nucleus
  • Cell Physiological Processes
  • Cells
  • Chromosome Structures
  • Chromosomes
  • Cytoskeleton
  • Fungi
  • Genes
  • Genetics
  • Intranuclear Space
  • North Carolina
  • Phase Separation
  • Phase Transformations
  • Polymers
  • Simulators
  • Statistics
  • Three Dimensional

Fields of Study

  • Biology

Readers

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