Send to

Choose Destination
Eur J Cell Biol. 2018 Mar;97(2):90-101. doi: 10.1016/j.ejcb.2017.12.003. Epub 2017 Dec 27.

The ABC transporter Snu and the extracellular protein Snsl cooperate in the formation of the lipid-based inward and outward barrier in the skin of Drosophila.

Author information

Applied Zoology, TU Dresden, Zellescher Weg 20b, 01217, Dresden, Germany.
Interfaculty Institute for Cell Biology, Animal Genetics, Auf der Morgenstelle 15, 72076 Tübingen, Germany.
Max-Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstr. 108, 01307, Dresden, Germany.
Rzeszow University, Department of Biochemistry and Cell Biology, ul. Zelwerowicza 4, 35-601 Rzeszów, Poland.
Max-Planck Institute for Developmental Biology, Spemannstr. 35, 72076 Tübingen, Germany.
Applied Zoology, TU Dresden, Zellescher Weg 20b, 01217, Dresden, Germany; iBV, Université Nice Sophia-Antipolis, Parc Valrose, 06108, Nice, France. Electronic address:


Lipids in extracellular matrices (ECM) contribute to barrier function and stability of epithelial tissues such as the pulmonary alveoli and the skin. In insects, skin waterproofness depends on the outermost layer of the extracellular cuticle termed envelope that contains cuticulin, an unidentified water-repellent complex molecule composed of proteins, lipids and catecholamines. Based on live-imaging analyses of fruit fly larvae, we find that initially envelope units are assembled within putative vesicles harbouring the ABC transporter Snu and the extracellular protein Snsl. In a second step, the content of these vesicles is distributed to cuticular lipid-transporting nanotubes named pore canals and to the cuticle surface in dependence of Snu function. Consistently, the surface of snu and snsl mutant larvae is depleted from lipids and cuticulin. By consequence, these animals suffer uncontrolled water loss and penetration of xenobiotics. Our data allude to a two-step model of envelope i.e. barrier formation. The proposed mechanism in principle parallels the events occurring during differentiation of the lipid-based ECM by keratinocytes in the vertebrate skin suggesting establishment of analogous mechanisms of skin barrier formation in vertebrates and invertebrates.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center