Condensin II drives large-scale folding and spatial partitioning of interphase chromosomes in Drosophila nuclei

PLoS Genet. 2018 Jul 12;14(7):e1007393. doi: 10.1371/journal.pgen.1007393. eCollection 2018 Jul.

Abstract

Metazoan chromosomes are folded into discrete sub-nuclear domains, referred to as chromosome territories (CTs). The molecular mechanisms that underlie the formation and maintenance of CTs during the cell cycle remain largely unknown. Here, we have developed high-resolution chromosome paints to investigate CT organization in Drosophila cycling cells. We show that large-scale chromosome folding patterns and levels of chromosome intermixing are remarkably stable across various cell types. Our data also suggest that the nucleus scales to accommodate fluctuations in chromosome size throughout the cell cycle, which limits the degree of intermixing between neighboring CTs. Finally, we show that the cohesin and condensin complexes are required for different scales of chromosome folding, with condensin II being especially important for the size, shape, and level of intermixing between CTs in interphase. These findings suggest that large-scale chromosome folding driven by condensin II influences the extent to which chromosomes interact, which may have direct consequences for cell-type specific genome stability.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphatases / metabolism*
  • Animals
  • Cell Cycle Proteins / metabolism
  • Cell Line
  • Cell Nucleus / metabolism*
  • Chromosomal Proteins, Non-Histone / metabolism
  • Chromosomes / metabolism*
  • DNA-Binding Proteins / metabolism*
  • Drosophila / physiology*
  • Drosophila Proteins / metabolism*
  • Genomic Instability / physiology
  • Interphase / genetics
  • Multiprotein Complexes / metabolism*

Substances

  • Cell Cycle Proteins
  • Chromosomal Proteins, Non-Histone
  • DNA-Binding Proteins
  • Drosophila Proteins
  • Multiprotein Complexes
  • cohesins
  • condensin complexes
  • Adenosine Triphosphatases