title: Isolation of factor Xa from chick embryo as the amniotic endoprotease responsible for paramyxovirus activation.
abstract: In chick embryo, certain paramyxoviruses mainly target the chorioallantois and the allantoamnion and show no extensive further spreading in the other organs. This has been explained by the possible presence of an endoprotease activating the viral fusion glycoprotein precursor in the allantoic and the amniotic fluid, and its absence in other places or organs. We previously isolated such an endoprotease from the allantoic fluid and demonstrated its identity with the clotting factor Xa. Exactly the same endoprotease by all the criteria including the N-terminal amino acid sequence was now isolated from the amniotic fluid. Thus, the factor Xa seems to be a major host determinant of the viral tropism in chick embryo.
authors.affiliation: Radioisotope Center Medical Division, Nagoya University School of Medicine, Japan.
authors.forename: B
authors.initials: B
authors.lastname: Gotoh
authors.forename: F
authors.initials: F
authors.lastname: Yamauchi
authors.forename: T
authors.initials: T
authors.lastname: Ogasawara
authors.forename: Y
authors.initials: Y
authors.lastname: Nagai
mesh_terms: D000595:Amino Acid Sequence; D000653:Amniotic Fluid / Q000201:enzymology*; D000818:Animals; D002642:Chick Embryo; D002850:Chromatography, Gel; D004591:Electrophoresis, Polyacrylamide Gel; D015951:Factor Xa / Q000737:chemistry / Q000302:isolation & purification / Q000502:physiology*; D008969:Molecular Sequence Data; D010252:Paramyxoviridae / Q000254:growth & development*; D016415:Sequence Alignment; D012697:Serine Endopeptidases / Q000737:chemistry / Q000302:isolation & purification / Q000502:physiology*; D014775:Virus Activation
chemical_list: D012697:Serine Endopeptidases; C066527:virus activating protease; D015951:Factor Xa