title: Identification of the hASCT2-binding domain of the Env ERVWE1/syncytin-1 fusogenic glycoprotein.
abstract: The cellular HERV-W envelope/syncytin-1 protein, encoded by the envelope gene of the ERVWE1 proviral locus is a fusogenic glycoprotein probably involved in the formation of the placental syncytiotrophoblast layer. Syncytin-1-induced in vitro cell-cell fusion is dependent on the interaction with hASCT2. As no receptor binding domain has been clearly defined in the SU of neither the HERV-W Env nor the retroviruses of the same interference group, we designed an in vitro binding assay to evaluate the interaction of the HERV-W envelope with the hASCT2 receptor. Using truncated HERV-W SU subunits, a region consisting of the N-terminal 124 amino acids of the mature SU glycoprotein was determined as the minimal receptor-binding domain. This domain contains several sub-domains which are poorly conserved among retroviruses of this interference group but a region of 18 residus containing the SDGGGX2DX2R conserved motif was proved to be essential for syncytin-1-hASCT2 interaction.
authors.affiliation: UMR 2714 CNRS-bioMérieux, IFR128 BioSciences Lyon-Gerland, Ecole Normale Supérieure de Lyon, 69364 Lyon Cedex 07, France. valerie.cheynet@ens-lyon.fr
authors.forename: Valérie
authors.initials: V
authors.lastname: Cheynet
authors.forename: Guy
authors.initials: G
authors.lastname: Oriol
authors.forename: François
authors.initials: F
authors.lastname: Mallet
mesh_terms: D026962:Amino Acid Transport System ASC / Q000378:metabolism*; D002459:Cell Fusion; D002460:Cell Line; D020077:Endogenous Retroviruses / Q000235:genetics*; D015686:Gene Products, env / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D015778:Minor Histocompatibility Antigens; D011257:Pregnancy Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D011991:Receptors, Virus / Q000378:metabolism
chemical_list: D026962:Amino Acid Transport System ASC; D015686:Gene Products, env; D015778:Minor Histocompatibility Antigens; D011257:Pregnancy Proteins; D011991:Receptors, Virus; C420506:SLC1A5 protein, human; C405335:syncytin