Formation of a Polycomb-Domain in the Absence of Strong Polycomb Response Elements.

摘要: Polycomb group response elements (PREs) in Drosophila are DNA-elements that recruit proteins (PcG) to chromatin and regulate gene expression. PREs easily recognizable the genome as strong peaks of PcG-protein binding over discrete DNA fragments; many small but statistically significant PcG also observed domains. Surprisingly, vivo deletion four characterized from regulated invected-engrailed (inv-en) complex did not disrupt formation H3K27me3 domain affect inv-en expression embryos or larvae suggesting presence redundant recruitment mechanism. Further, 3D-structure was only minimally altered by PREs. A reporter construct containing a 7.5kb en fragment contains three weak no large forms an is PcG-regulated. Our data suggests model for PcG-complexes genes via interactions with multiple, spread throughout domain.