title: The sulfonylurea receptor Sur is dispensable for chitin synthesis in Drosophila melanogaster embryos.
abstract: BACKGROUND
  Chitin produced by membrane-inserted chitin synthases is an important constituent of the arthropod cuticle and midgut peritrophic matrix. Chitin synthesis inhibitors are common insecticides in pest control. As the target of sulfonylurea-derived insecticides such as diflubenzuron, the ABC transporter sulfonylurea receptor (Sur) has been postulated to be an essential cofactor of chitin synthesis. However, direct evidence for this assumption is missing.
  
  
  RESULTS
  Here, a study has been made of the phenotype of Drosophila melanogaster larvae suffering completely eliminated Sur function. Taken together, it is found that cuticle architecture is normal and chitin amounts are not diminished in the cuticle of these animals, indicating that Sur is dispensable for chitin synthesis.
  
  
  CONCLUSIONS
  The data obtained suggest that there must exist another sulfonylurea-sensitive ABC transporter that either instead of Sur is the true sulfonylurea-sensitive transporter involved in chitin synthesis or is able to substitute Sur function during cuticle formation. Identification and characterisation of this factor is pivotal for understanding the mode of action of sulfonylurea as insecticide.
authors: Animal Genetics, Interfaculty Institute for Cell Biology, University of Tübingen, Tübingen, Germany.
authors: Frauke
authors: F
authors: Meyer
authors: Matthias
authors: M
authors: Flötenmeyer
authors: Bernard
authors: B
authors: Moussian
mesh_terms: D000818:Animals; D002686:Chitin / Q000096:biosynthesis*; D004132:Diflubenzuron / Q000494:pharmacology; D004331:Drosophila melanogaster / Q000187:drug effects / Q000196:embryology* / Q000235:genetics / Q000378:metabolism*; D007306:Insecticides / Q000494:pharmacology; D007814:Larva / Q000187:drug effects / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D064233:Sulfonylurea Receptors / Q000235:genetics / Q000378:metabolism*
chemical_list: D007306:Insecticides; D064233:Sulfonylurea Receptors; C577513:sulfonylurea receptor, Drosophila; D002686:Chitin; D004132:Diflubenzuron
keywords: ABC transporter; Cuticle, epidermis; benzoylphenylurea; glibenclamide