The insulator protein SU(HW) fine-tunes nuclear lamina interactions of the Drosophila genome

PLoS One. 2010 Nov 24;5(11):e15013. doi: 10.1371/journal.pone.0015013.


Specific interactions of the genome with the nuclear lamina (NL) are thought to assist chromosome folding inside the nucleus and to contribute to the regulation of gene expression. High-resolution mapping has recently identified hundreds of large, sharply defined lamina-associated domains (LADs) in the human genome, and suggested that the insulator protein CTCF may help to demarcate these domains. Here, we report the detailed structure of LADs in Drosophila cells, and investigate the putative roles of five insulator proteins in LAD organization. We found that the Drosophila genome is also organized in discrete LADs, which are about five times smaller than human LADs but contain on average a similar number of genes. Systematic comparison to new and published insulator binding maps shows that only SU(HW) binds preferentially at LAD borders and at specific positions inside LADs, while GAF, CTCF, BEAF-32 and DWG are mostly absent from these regions. By knockdown and overexpression studies we demonstrate that SU(HW) weakens genome - NL interactions through a local antagonistic effect, but we did not obtain evidence that it is essential for border formation. Our results provide insights into the evolution of LAD organization and identify SU(HW) as a fine-tuner of genome - NL interactions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Binding Sites / genetics
  • Blotting, Western
  • Cell Line
  • Chromatin / metabolism
  • Drosophila Proteins / genetics
  • Drosophila Proteins / metabolism*
  • Drosophila melanogaster / cytology
  • Drosophila melanogaster / genetics
  • Drosophila melanogaster / metabolism*
  • Gene Expression Profiling
  • Genome, Insect*
  • Humans
  • Insulator Elements / genetics
  • Nuclear Lamina / metabolism*
  • Protein Binding
  • RNA Interference
  • Repressor Proteins / genetics
  • Repressor Proteins / metabolism*


  • Chromatin
  • Drosophila Proteins
  • Repressor Proteins
  • su(Hw) protein, Drosophila

Associated data

  • GEO/GSE20313