Long-range chromatin interactions
Many genes require additional regulatory regions of DNA known as enhancers that are often located considerable distances from the gene along the chromatin fiber. We have shown, using RNA TRAP (tagging and recovery of associated proteins), that distant enhancers actually physically contact their target genes in the nucleus by looping out the intervening DNA.
Such long-range interactions between enhancers and genes are powerful switches that turn on transcription of individual genes resulting in high levels of expression. Our work suggests that these regulatory interactions between enhancers and genes can only occur if the chromatin containing them is first remodelled to the open state by transcription factors and histone modifications.
For more information see: Long-range chromatin regulatory interactions in vivo
Nature genetics 32 (4), 623-626