摘要：SummaryThe cuticle ofC. elegansis 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 theC. eleganscuticle. Agmap-1deletion 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 thisgmap-1permeability 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 whilein 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 ofC. elegans.Graphical abstractDisplay OmittedHighlights•GMAP-1 is secreted by the hypodermis toward the cuticle ofCaenorhabditis elegans•GMAP-1 binds and shuttle phosphoglycerides•GMAP-1 sets the lipid composition of the cuticle•While healthy,gmap-1mutant displays high cuticular permeabilityBiological sciences, molecular biology, physiology
