PGP-14 establishes a polar lipid permeability barrier within the < i > C < /i > . < i > elegans < /i > pharyngeal cuticle

by Muntasir Kamal, Levon Tokmakjian, Jessica Knox, Duhyun Han, Houtan Moshiri, Lilia Magomedova, Ken CQ Nguyen, Hong Zheng, Andrew R. Burns, Brittany Cooke, Jessica Lacoste, May Yeo, David H. Hall, Carolyn L. Cummins, Peter J. Roy The cuticles of ecdysozoan animals are barriers to material loss and xenobiotic insult. Key to this barrier is lipid content, the establishment of which is poorly understood. Here, we show that the p-glycoprotein PGP-14 functions coincidently with the sphingomyelin synthase SMS-5 to establish a polar lipid barrier within the pharyngeal cuticle of the nematodeC.elegans. We show that PGP-14 and SMS-5 are coincidentally expressed in the epithelium that surrounds the anterior pharyngeal cuticle where PGP-14 localizes to the apical membrane.pgp-14 andsms-5 also peak in expression at the time of new cuticle synthesis. Loss of PGP-14 and SMS-5 dramatically reduces pharyngeal cuticle staining by Nile Red, a key marker of polar lipids, and coincidentally alters the nematode ’s response to a wide-range of xenobiotics. We infer that PGP-14 exports polar lipids into the developing pharyngeal cuticle in an SMS-5-dependent manner to safeguard the nematode from environmental insult.
Source: PLoS Genetics - Category: Genetics & Stem Cells Authors: Source Type: research