Identification and characterization of a new member of the gas3/PMP22 gene family in C. elegans.

The Gas3/PMP22 protein family is characterized by tetraspan transmembrane proteins. The gas3/PMP22 gene is highly expressed in Schwann cells of the peripheral nervous system, and different alterations of this gene are associated with hereditary demyelinating neuropathies, such as the Charcot-Marie-Tooth type 1A, the Dejerine-Sottas syndrome and the Hereditary Liability to Pressure Palsies (HNPP).Here, we report on the identification of at least one member of the Gas3/PMP22 family in the nematode C. elegans (C01C10.1b). C01C10.1b shares 36% of identical amino acids with the human Gas3/PMP22 and is characterized by four hydrophobic putative transmembrane domains. It lacks the typical N-linked glycosylation consensus in the first extracellular loop. C01C10.1b is transcribed as an operon downstream to the gene C01C10.1a, which encodes for a putative tetraspan protein with less conserved homology with the Gas3/PMP22 family. Interestingly, C01C10.1a contains three N-glycosylation sites at the C-terminus. Both genes are expressed in different nematode developmental stages and in the adults. The characterization of one member of the gas3/PMP22 family in C. elegans gives the opportunity to use this model organism to investigate the role of gas3/PMP22 in the regulation of cell proliferation and differentiation and its relation to the hereditary neurodegenerative diseases in humans.