Coordinated control of dCTCF and gypsy chromatin insulators in Drosophila.
CTCF plays a central role in vertebrate insulators and forms part of the Fab-8 insulator in Drosophila. dCTCF is present at hundreds of sites in the Drosophila genome, where it is located at the boundaries between bands and interbands in polytene chromosomes. dCTCF colocalizes with CP190, which is required for proper binding of dCTCF to chromatin, but not with the other gypsy insulator proteins Su(Hw) or Mod(mdg4)2.2. Mutations in the CP190 gene affect Fab-8 insulator activity, suggesting that CP190 is an essential component of both gypsy and dCTCF insulators. dCTCF is present at specific nuclear locations, forming large insulator bodies that overlap with those formed by Su(Hw), Mod(mdg4)2.2, and CP190. The results suggest that Su(Hw) and dCTCF may be the DNA-binding components of two different subsets of insulators that share CP190 and cooperate in the formation of insulator bodies to regulate the organization of the chromatin fiber in the nucleus.
Gerasimova
Tatiana I
TI
Department of Biology, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218, USA.
Lei
Elissa P
EP
Bushey
Ashley M
AM
Corces
Victor G
VG
D000818:Animals; D030801:Animals, Genetically Modified; D001665:Binding Sites; D000076246:CCCTC-Binding Factor; D002467:Cell Nucleus; D002843:Chromatin / Q000737:chemistry* / Q000378:metabolism; D047369:Chromatin Immunoprecipitation; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism*; D029721:Drosophila Proteins / Q000235:genetics* / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D017403:In Situ Hybridization; D038101:Insulator Elements / Q000502:physiology*; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D012097:Repressor Proteins / Q000235:genetics* / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D020798:Two-Hybrid System Techniques
D000076246:CCCTC-Binding Factor; C107964:CP190 protein, Drosophila; C524946:CTCF protein, Drosophila; D002843:Chromatin; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D008869:Microtubule-Associated Proteins; D009687:Nuclear Proteins; D012097:Repressor Proteins; D014157:Transcription Factors; C101384:mod(mdg4) protein, Drosophila; C083738:su(Hw) protein, Drosophila