title: An aspartic proteinase expressed in the equine placenta.
abstract: This manuscript describes the cloning of a novel aspartic proteinase expressed in the placenta of the horse (order Perrisodactyla). Evidence for similar genes in the cat (Carnivora) and ruminants (Artiodactyla), indicates that these molecules have been conserved within widely divergent species with distinct types of placentation. Since ePAG is produced by the outer cell layer (trophoblast) of the placenta, it can tentatively be grouped with the pregnancy-associated glycoproteins (PAG) of cattle, sheep, and pig. The high sequence identity that ePAG shares with pepsinogens as well as the PAG, indicates that ePAG may be the evolutionary bridge that links these two groups of aspartic proteinases.
authors.affiliation: Department of Animal Sciences, University of Missouri, Columbia 65211, USA.
authors.forename: J
authors.initials: J
authors.lastname: Green
authors.forename: S
authors.initials: S
authors.lastname: Xie
authors.forename: X
authors.initials: X
authors.lastname: Gan
authors.forename: R M
authors.initials: RM
authors.lastname: Roberts
mesh_terms: D000818:Animals; D016282:Aspartic Acid Endopeptidases / Q000235:genetics*; D002415:Cats; D002417:Cattle; D018076:DNA, Complementary; D015870:Gene Expression; D006023:Glycoproteins / Q000235:genetics*; D006736:Horses; D010920:Placenta / Q000201:enzymology*; D011257:Pregnancy Proteins / Q000235:genetics*; D012333:RNA, Messenger
chemical_list: D018076:DNA, Complementary; D006023:Glycoproteins; D011257:Pregnancy Proteins; D012333:RNA, Messenger; D016282:Aspartic Acid Endopeptidases; C094766:pregnancy-associated glycoprotein 1