The ISWI chromatin remodeler organizes the hsrω ncRNA-containing omega speckle nuclear compartments

PLoS Genet. 2011 May;7(5):e1002096. doi: 10.1371/journal.pgen.1002096. Epub 2011 May 26.

Abstract

The complexity in composition and function of the eukaryotic nucleus is achieved through its organization in specialized nuclear compartments. The Drosophila chromatin remodeling ATPase ISWI plays evolutionarily conserved roles in chromatin organization. Interestingly, ISWI genetically interacts with the hsrω gene, encoding multiple non-coding RNAs (ncRNA) essential, among other functions, for the assembly and organization of the omega speckles. The nucleoplasmic omega speckles play important functions in RNA metabolism, in normal and stressed cells, by regulating availability of hnRNPs and some other RNA processing proteins. Chromatin remodelers, as well as nuclear speckles and their associated ncRNAs, are emerging as important components of gene regulatory networks, although their functional connections have remained poorly defined. Here we provide multiple lines of evidence showing that the hsrω ncRNA interacts in vivo and in vitro with ISWI, regulating its ATPase activity. Remarkably, we found that the organization of nucleoplasmic omega speckles depends on ISWI function. Our findings highlight a novel role for chromatin remodelers in organization of nucleoplasmic compartments, providing the first example of interaction between an ATP-dependent chromatin remodeler and a large ncRNA.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphatases / genetics
  • Adenosine Triphosphatases / metabolism*
  • Alleles
  • Animals
  • Cell Nucleus / genetics
  • Cell Nucleus / metabolism
  • Chromatin Assembly and Disassembly*
  • Chromosomes / metabolism
  • Drosophila / anatomy & histology
  • Drosophila / genetics*
  • Drosophila / metabolism
  • Drosophila Proteins / genetics
  • Drosophila Proteins / metabolism
  • Epistasis, Genetic
  • Eye / anatomy & histology
  • Fluorescent Antibody Technique
  • Heterogeneous-Nuclear Ribonucleoproteins / genetics
  • Heterogeneous-Nuclear Ribonucleoproteins / metabolism
  • Larva / anatomy & histology
  • Larva / genetics
  • Larva / metabolism
  • Male
  • Phenotype
  • RNA Interference
  • RNA, Untranslated / genetics
  • RNA, Untranslated / metabolism*
  • RNA-Binding Proteins / genetics
  • RNA-Binding Proteins / metabolism
  • Tandem Repeat Sequences
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*

Substances

  • Drosophila Proteins
  • Heterogeneous-Nuclear Ribonucleoproteins
  • ISWI protein
  • RNA, Untranslated
  • RNA-Binding Proteins
  • Transcription Factors
  • Adenosine Triphosphatases