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  • The EMBO Journal (2007) 26, 4203 - 4214
  • doi:10.1038/sj.emboj.7601851

Published online: 6 September 2007

The Drosophila insulator proteins CTCF and CP190 link enhancer blocking to body patterning

Man Mohan1, Marek Bartkuhn1, Martin Herold1, Angela Philippen1, Nina Heinl1, Imke Bardenhagen1, Joerg Leers1, Robert AH White2, Renate Renkawitz-Pohl3, Harald Saumweber4 and Rainer Renkawitz1

  1. Institute for Genetics, Justus-Liebig-University Giessen, Heinrich-Buff-Ring, Giessen, Germany
  2. Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK
  3. Philipps-Universität Marburg, Fachbereich Biologie, Entwicklungsbiologie, Marburg, Germany
  4. Cytogenetics Division, Institute of Biology, Humboldt University, Berlin, Germany

Correspondence to:

Rainer Renkawitz, Institute for Genetics, Justus-Liebig-University Giessen, Heinrich-Buff-Ring 58-62, Giessen 35392, Germany. Tel.: +49 641 99 35460; Fax: +49 641 99 35469; E-mail: rainer.renkawitz@gen.bio.uni-giessen.de

Received 22 May 2007; Accepted 15 August 2007

Insulator sequences guide the function of distantly located enhancer elements to the appropriate target genes by blocking inappropriate interactions. In Drosophila, five different insulator binding proteins have been identified, Zw5, BEAF-32, GAGA factor, Su(Hw) and dCTCF. Only dCTCF has a known conserved counterpart in vertebrates. Here we find that the structurally related factors dCTCF and Su(Hw) have distinct binding targets. In contrast, the Su(Hw) interacting factor CP190 largely overlapped with dCTCF binding sites and interacts with dCTCF. Binding of dCTCF to targets requires CP190 in many cases, whereas others are independent of CP190. Analysis of the bithorax complex revealed that six of the borders between the parasegment specific regulatory domains are bound by dCTCF and by CP190 in vivo. dCTCF null mutations affect expression of Abdominal-B, cause pharate lethality and a homeotic phenotype. A short pulse of dCTCF expression during larval development rescues the dCTCF loss of function phenotype. Overall, we demonstrate the importance of dCTCF in fly development and in the regulation of abdominal segmentation.

  • Keywords:

    • Abdominal-B,
    • bithorax complex,
    • CP190,
    • homeotic,
    • Hox