title: Shaping cells and organs in Drosophila by opposing roles of fat body-secreted Collagen IV and perlecan.
abstract: Basement membranes (BMs) are resilient polymer structures that surround organs in all animals. Tissues, however, undergo extensive morphological changes during development. It is not known whether the assembly of BM components plays an active morphogenetic role. To study in vivo the biogenesis and assembly of Collagen IV, the main constituent of BMs, we used a GFP-based RNAi method (iGFPi) designed to knock down any GFP-trapped protein in Drosophila. We found with this method that Collagen IV is synthesized by the fat body, secreted to the hemolymph (insect blood), and continuously incorporated into the BMs of the larva. We also show that incorporation of Collagen IV determines organ shape, first by mechanically constricting cells and second through recruitment of Perlecan, which counters constriction by Collagen IV. Our results uncover incorporation of Collagen IV and Perlecan into BMs as a major determinant of organ shape and animal form.
authors.affiliation: Howard Hughes Medical Institute, Department of Genetics, Yale University School of Medicine, 295 Congress Avenue, New Haven, CT 06519, USA.
authors.forename: José Carlos
authors.initials: JC
authors.lastname: Pastor-Pareja
authors.forename: Tian
authors.initials: T
authors.lastname: Xu
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D001485:Basement Membrane / Q000378:metabolism; D048430:Cell Shape / Q000502:physiology*; D024141:Collagen Type IV / Q000235:genetics / Q000378:metabolism*; D004330:Drosophila; D029721:Drosophila Proteins / Q000235:genetics; D005216:Fat Body / Q000166:cytology* / Q000378:metabolism* / Q000648:ultrastructure; D018507:Gene Expression Regulation, Developmental / Q000235:genetics / Q000502:physiology; D049452:Green Fluorescent Proteins / Q000235:genetics; D019812:Heparan Sulfate Proteoglycans / Q000378:metabolism*; D007814:Larva; D018613:Microscopy, Confocal; D046529:Microscopy, Electron, Transmission; D008954:Models, Biological; D034622:RNA Interference / Q000502:physiology; D014921:Wings, Animal / Q000254:growth & development* / Q000648:ultrastructure
chemical_list: D024141:Collagen Type IV; D029721:Drosophila Proteins; D019812:Heparan Sulfate Proteoglycans; C071927:perlecan; D049452:Green Fluorescent Proteins