title: The bHLH transcription factor hand is required for proper wing heart formation in Drosophila.
abstract: The Hand basic helix-loop-helix transcription factors play an important role in the specification and patterning of various tissues in vertebrates and invertebrates. Here, we have investigated the function of Hand in the development of the Drosophila wing hearts which consist of somatic muscle cells as well as a mesodermally derived epithelium. We found that Hand is essential in both tissues for proper organ formation. Loss of Hand leads to a reduced number of cells in the mature organ and loss of wing heart functionality. In wing heart muscles Hand is required for the correct positioning of attachment sites, the parallel alignment of muscle cells, and the proper orientation of myofibrils. At the protein level, α-Spectrin and Dystroglycan are misdistributed suggesting a defect in the costameric network. Hand is also required for proper differentiation of the wing heart epithelium. Additionally, the handC-GFP reporter line is not active in the mutant suggesting an autoregulatory role of Hand in wing hearts. Finally, in a candidate-based RNAi mediated knock-down approach we identified Daughterless and Nautilus as potential dimerization partners of Hand in wing hearts.
authors.affiliation: Department of Biology, University of Osnabrück, Barbarastraße 11, D-49069 Osnabrück, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Tögel
authors.forename: Heiko
authors.initials: H
authors.lastname: Meyer
authors.forename: Christine
authors.initials: C
authors.lastname: Lehmacher
authors.forename: Jürgen J
authors.initials: JJ
authors.lastname: Heinisch
authors.forename: Günther
authors.initials: G
authors.lastname: Pass
authors.forename: Achim
authors.initials: A
authors.lastname: Paululat
mesh_terms: D022005:Adherens Junctions / Q000235:genetics / Q000378:metabolism; D000818:Animals; D017209:Apoptosis; D051186:Armadillo Domain Proteins / Q000235:genetics / Q000378:metabolism; D051792:Basic Helix-Loop-Helix Proteins / Q000235:genetics / Q000378:metabolism*; D002454:Cell Differentiation; D004330:Drosophila / Q000196:embryology / Q000378:metabolism*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D049030:Dystroglycans / Q000235:genetics / Q000378:metabolism; D004848:Epithelium / Q000378:metabolism; D016326:Extracellular Matrix Proteins / Q000235:genetics / Q000378:metabolism; D005260:Female; D005426:Flight, Animal; D018507:Gene Expression Regulation, Developmental; D055785:Gene Knockdown Techniques; D008297:Male; D008648:Mesoderm / Q000166:cytology / Q000378:metabolism; D024510:Muscle Development; D009132:Muscles / Q000196:embryology / Q000378:metabolism; D025941:Protein Interaction Mapping; D055503:Protein Multimerization; D013049:Spectrin / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D014921:Wings, Animal / Q000196:embryology* / Q000378:metabolism
chemical_list: D051186:Armadillo Domain Proteins; D051792:Basic Helix-Loop-Helix Proteins; D029721:Drosophila Proteins; D049030:Dystroglycans; D016326:Extracellular Matrix Proteins; D013049:Spectrin; D014157:Transcription Factors; C495305:ARM protein, Drosophila; C550355:Dg protein, Drosophila; C475488:Hand protein, Drosophila
keywords: Adult myogenesis; Armadillo; Dystroglycan; Muscle attachment; Spectrin; Wing maturation