On the mechanism of induction of heterochromatin by the RNA-binding protein vigilin

RNA. 2008 Sep;14(9):1773-81. doi: 10.1261/rna.1036308. Epub 2008 Jul 22.

Abstract

Vigilin is an RNA-binding protein localized to both the cytoplasm and the nucleus and has been previously implicated in heterochromatin formation and chromosome segregation. We demonstrate here that the C-terminal domain of human vigilin binds to the histone methyltransferase SUV39H1 in vivo. This association is independent of RNA and maps to a site on vigilin that is not involved in its interaction with several other known protein partners. Cells that express high levels of the C-terminal fragment display chromosome segregation defects, and ChIP analyses show changes in the status of pericentric beta-satellite and rDNA chromatin from heterochromatic to more euchromatic form. Finally, a cell line with inducible expression of the vigilin C-terminal fragment displays inducible alterations in beta-satellite chromatin. These and other results lead us to present a new model for vigilin-mediated, RNA-induced gene silencing.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antigens, Nuclear / metabolism
  • Cell Line
  • Chromatin Immunoprecipitation
  • Chromosome Segregation / genetics
  • DEAD-box RNA Helicases / metabolism
  • DNA-Binding Proteins / metabolism
  • Gene Silencing*
  • Heterochromatin / metabolism*
  • Humans
  • Ku Autoantigen
  • Methyltransferases / metabolism*
  • Neoplasm Proteins / metabolism
  • Protein Structure, Tertiary
  • RNA / metabolism
  • RNA-Binding Proteins / genetics
  • RNA-Binding Proteins / metabolism*
  • Repressor Proteins / metabolism*

Substances

  • Antigens, Nuclear
  • DNA-Binding Proteins
  • Heterochromatin
  • Neoplasm Proteins
  • RNA-Binding Proteins
  • Repressor Proteins
  • high density lipoprotein binding protein
  • RNA
  • SUV39H1 protein, human
  • Methyltransferases
  • DHX9 protein, human
  • Xrcc6 protein, human
  • DEAD-box RNA Helicases
  • Ku Autoantigen