CTCF binding profiles in Drosophila melanogaster 3rd instar larva T1 and T3 leg discs
Ontology highlight
ABSTRACT:
ORGANISM(S): Drosophila melanogaster
SUBMITTER: Robert White
PROVIDER: E-GEOD-62234 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
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Project description:Although the majority of genomic binding sites for the insulator protein CTCF are constitutively occupied, a subset show variable occupancy. Such variable sites provide an opportunity to assess context-specific CTCF functions in gene regulation. Here we have identified a variably occupied CTCF site in the Ultrabithorax (Ubx) gene in Drosophila. This site is occupied in tissues where Ubx is active (third thoracic imaginal leg disc) but is not bound in tissues where the Ubx gene is repressed (first thoracic imaginal leg disc).
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Project description:The Hox genes are responsible for generating morphological diversity along the anterior-posterior axis during animal development. The Drosophila Hox gene Ultrabithorax (Ubx), for example, is required for specifying the identity of the third thoracic (T3) segment of the adult, which includes the dorsal haltere, an appendage required for flight, and the ventral T3 leg. Ubx mutants show homeotic transformations of the T3 leg towards the identity of the T2 leg and the haltere towards the wing. All Hox genes, including Ubx, encode homeodomain containing transcription factors, raising the question of what target genes Ubx regulates to generate these adult structures. To address this question, we carried out whole genome ChIP-chip studies to identify all of the Ubx bound regions in the haltere and T3 leg imaginal discs, which are the precursors to these adult structures. In addition, we used ChIP-chip to identify the sites bound by the Hox cofactor, Homothorax (Hth). This is a dataset generated by the Drosophila Regulatory Elements modENCODE Project led by Kevin P. White at the University of Chicago. This dataset was generated in collaboration with Richard S. Mann at Columbia University. It contains ChIP-chip data on Affymetrix Drosophila Tiling 2.0R arrays for multiple transcription factor antibodies in multiple Drosophila tissues. For data usage terms and conditions, please refer to http://www.genome.gov/27528022 and http://www.genome.gov/Pages/Research/ENCODE/ENCODEDataReleasePolicyFinal2008.pdf Haltere or leg imaginal discs ChIPped for Ubx or Hth vs. input DNA from corresponding imaginal discs. For each combination of tissue and antibody, ChIP experiments have been performed and hybridized on Affymetrix Drosophila Tiling 2.0R arrays. At least 3 biological replicates for the ChIP sample have been hybridized.
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