Association of transcriptionally silent genes with Ikaros complexes at centromeric heterochromatin

Cell. 1997 Dec 12;91(6):845-54. doi: 10.1016/s0092-8674(00)80472-9.


Ikaros proteins are required for normal T, B, and NK cell development and are postulated to activate lymphocyte-specific gene expression. Here we examined Ikaros distribution in the nucleus of B lymphocytes using confocal microscopy and a novel immunofluorescence in situ hybridization (immuno-FISH) approach. Unexpectedly, Ikaros localized to discrete heterochromatin-containing foci in interphase nuclei, which comprise clusters of centromeric DNA as defined by gamma-satellite sequences and the abundance of heterochromatin protein-1 (HP-1). Using locus-specific probes for CD2, CD4, CD8alpha, CD19, CD45, and lambda5 genes, we show that transcriptionally inactive but not transcriptionally active genes associate with Ikaros-heterochromatin foci. These findings support a model of organization of the nucleus in which repressed genes are selectively recruited into centromeric domains.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Antigens, CD / biosynthesis
  • Antigens, Differentiation, B-Lymphocyte / biosynthesis
  • Antigens, Differentiation, B-Lymphocyte / genetics
  • B-Lymphocytes / physiology
  • Cell Line
  • Cell Nucleus / physiology
  • Cell Nucleus / ultrastructure
  • Centromere / physiology*
  • Centromere / ultrastructure
  • DNA-Binding Proteins*
  • Gene Expression Regulation
  • Heterochromatin / physiology*
  • Heterochromatin / ultrastructure
  • Ikaros Transcription Factor
  • Lymphoma
  • Mice
  • Mice, Transgenic
  • Models, Genetic
  • Polymerase Chain Reaction
  • Receptors, Interleukin / biosynthesis
  • Receptors, Interleukin-7
  • Transcription Factors / analysis
  • Transcription Factors / metabolism*
  • Transcription, Genetic*
  • Zinc Fingers


  • Antigens, CD
  • Antigens, Differentiation, B-Lymphocyte
  • DNA-Binding Proteins
  • Heterochromatin
  • Receptors, Interleukin
  • Receptors, Interleukin-7
  • Transcription Factors
  • Zfpn1a1 protein, mouse
  • Ikaros Transcription Factor