title: Drosophila left/right asymmetry establishment is controlled by the Hox gene abdominal-B.
abstract: In Drosophila, left/right (LR) asymmetry is apparent in the directional looping of the gut and male genitalia. The dextral orientation of the organs depends on the activity of a single gene, MyosinID (myoID), whose mutation leads to a fully inverted LR axis, thus revealing the activity of a recessive sinistral pathway. Here, we present the identification of the Hox gene Abdominal-B (Abd-B) as an upstream regulator of LR determination. This role appears distinct from its function in anteroposterior patterning. We show that the Abd-Bm isoform binds to regulatory sequences of myoID and controls MyoID expression in the organ LR organizer. Abd-Bm is also required for the sinistral pathway. Thus, when Abd-B activity is missing, no symmetry breaking occurs and flies develop symmetrically. These findings identify the Hox gene Abd-B as directing the earliest events of LR asymmetry establishment in Drosophila.
authors: Institute of Biology Valrose, iBV, University of Nice Sophia-Antipolis, UMR7277-CNRS, UMR1091-INSERM, Parc Valrose, 06108 Nice Cedex 2, France.
authors: Jean-Baptiste
authors: JB
authors: Coutelis
authors: Charles
authors: C
authors: Géminard
authors: Pauline
authors: P
authors: Spéder
authors: Magali
authors: M
authors: Suzanne
authors: Astrid Gerlinde
authors: AG
authors: Petzoldt
authors: Stéphane
authors: S
authors: Noselli
mesh_terms: D000818:Animals; D019521:Body Patterning; D004065:Digestive System Abnormalities / Q000196:embryology / Q000378:metabolism*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000254:growth & development* / Q000378:metabolism; D041981:Gastrointestinal Tract / Q000002:abnormalities / Q000196:embryology / Q000378:metabolism*; D006066:Gonads / Q000002:abnormalities / Q000196:embryology / Q000378:metabolism*; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism*; D007124:Immunoenzyme Techniques; D008297:Male; D024461:Myosin Type I / Q000235:genetics / Q000378:metabolism*; D020033:Protein Isoforms
chemical_list: C062393:Abd-B proteins, Drosophila; D029721:Drosophila Proteins; D018398:Homeodomain Proteins; D020033:Protein Isoforms; D024461:Myosin Type I