iScience (Nov 2022)

A lipid transfer protein ensures nematode cuticular impermeability

  • Ferdinand Ngale Njume,
  • Adria Razzauti,
  • Miguel Soler,
  • Veronika Perschin,
  • Gholamreza Fazeli,
  • Axelle Bourez,
  • Cedric Delporte,
  • Stephen M. Ghogomu,
  • Philippe Poelvoorde,
  • Simon Pichard,
  • Catherine Birck,
  • Arnaud Poterszman,
  • Jacob Souopgui,
  • Pierre Van Antwerpen,
  • Christian Stigloher,
  • Luc Vanhamme,
  • Patrick Laurent

Journal volume & issue
Vol. 25, no. 11
p. 105357

Abstract

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Summary: The cuticle of C. elegans is impermeable to chemicals, toxins, and pathogens. However, increased permeability is a desirable phenotype because it facilitates chemical uptake. Surface lipids contribute to the permeability barrier. Here, we identify the lipid transfer protein GMAP-1 as a critical element setting the permeability of the C. elegans cuticle. A gmap-1 deletion mutant increases cuticular permeability to sodium azide, levamisole, Hoechst, and DiI. Expressing GMAP-1 in the hypodermis or transiently in the adults is sufficient to rescue this gmap-1 permeability phenotype. GMAP-1 protein is secreted from the hypodermis to the aqueous fluid filling the space between collagen fibers of the cuticle. In vitro, GMAP-1 protein binds phosphatidylserine and phosphatidylcholine while in vivo, GMAP-1 sets the surface lipid composition and organization. Altogether, our results suggest GMAP-1 secreted by hypodermis shuttles lipids to the surface to form the permeability barrier of C. elegans.

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