Polycomb-dependent regulatory contacts between distant Hox loci in Drosophila.
In Drosophila melanogaster, Hox genes are organized in an anterior and a posterior cluster, called Antennapedia complex and bithorax complex, located on the same chromosome arm and separated by 10 Mb of DNA. Both clusters are repressed by Polycomb group (PcG) proteins. Here, we show that genes of the two Hox complexes can interact within nuclear PcG bodies in tissues where they are corepressed. This colocalization increases during development and depends on PcG proteins. Hox gene contacts are conserved in the distantly related Drosophila virilis species and they are part of a large gene interaction network that includes other PcG target genes. Importantly, mutations on one of the loci weaken silencing of genes in the other locus, resulting in the exacerbation of homeotic phenotypes in sensitized genetic backgrounds. Thus, the three-dimensional organization of Polycomb target genes in the cell nucleus stabilizes the maintenance of epigenetic gene silencing.
Institut de Génétique Humaine, CNRS UPR 1142, Montpellier, France. frederic.bantignies@igh.cnrs.fr
Frédéric
F
Bantignies
Virginie
V
Roure
Itys
I
Comet
Benjamin
B
Leblanc
Bernd
B
Schuettengruber
Jérôme
J
Bonnet
Vanessa
V
Tixier
André
A
Mas
Giacomo
G
Cavalli
D000818:Animals; D051943:Antennapedia Homeodomain Protein / Q000235:genetics; D002467:Cell Nucleus / Q000378:metabolism; D004330:Drosophila / Q000235:genetics* / Q000378:metabolism*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism; D004331:Drosophila melanogaster / Q000235:genetics / Q000378:metabolism; D020868:Gene Silencing; D005801:Genes, Homeobox; D063146:Polycomb-Group Proteins; D050436:Regulatory Elements, Transcriptional; D012097:Repressor Proteins / Q000378:metabolism*
D051943:Antennapedia Homeodomain Protein; D029721:Drosophila Proteins; D063146:Polycomb-Group Proteins; D012097:Repressor Proteins