title: Genome-level identification of targets of Hox protein Ultrabithorax in Drosophila: novel mechanisms for target selection.
abstract: Hox proteins are transcription factors and key regulators of segmental identity along the anterior posterior axis across all bilaterian animals. Despite decades of research, the mechanisms by which Hox proteins select and regulate their targets remain elusive. We have carried out whole-genome ChIP-chip experiments to identify direct targets of Hox protein Ultrabithorax (Ubx) during haltere development in Drosophila. Direct targets identified include upstream regulators or cofactors of Ubx. Homothorax, a cofactor of Ubx during embryonic development, is one such target and is required for normal specification of haltere. Although Ubx bound sequences are conserved amongst various insect genomes, no consensus Ubx-specific motif was detected. Surprisingly, binding motifs for certain transcription factors that function either upstream or downstream to Ubx are enriched in these sequences suggesting complex regulatory loops governing Ubx function. Our data supports the hypothesis that specificity during Hox target selection is achieved by associating with other transcription factors.
authors.affiliation: Indian Institute of Science Education and Research, Pune, 411021, India.
authors.forename: Pavan
authors.initials: P
authors.lastname: Agrawal
authors.forename: Farhat
authors.initials: F
authors.lastname: Habib
authors.forename: Ramesh
authors.initials: R
authors.lastname: Yelagandula
authors.forename: L S
authors.initials: LS
authors.lastname: Shashidhara
mesh_terms: D020816:Amino Acid Motifs; D000818:Animals; D000911:Antibodies, Monoclonal / Q000378:metabolism; D047369:Chromatin Immunoprecipitation; D015536:Down-Regulation; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000196:embryology / Q000235:genetics*; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D049750:Genome, Insect; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism*; D034622:RNA Interference; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: D000911:Antibodies, Monoclonal; D029721:Drosophila Proteins; D018398:Homeodomain Proteins; D014157:Transcription Factors; C066177:Ubx protein, Drosophila