title: An amphibian two-domain 'big' neurophysin: conformational homology with the mammalian MSEL-neurophysin/copeptin intermediate precursor shown by trypsin-sepharose proteolysis.
abstract: A 'big' frog (Rana esculenta) neurophysin, encompassing sequences homologous to mammalian MSEL-neurophysin and copeptin, has been passed through a trypsin-Sepharose column in order to compare its conformation with that of the two-domain intermediate precursor isolated from guinea pig. Whereas the polypeptide possesses 8 arginine residues, only two cleavages were observed located in a putative inter-domain sequence (at Arg-94 and Arg-114). Because free vasotocin has been isolated from the frog, it is assumed that pro-vasotocin has a three-domain conformation similar to that of pro-vasopressin but processing in amphibians involves only one step rather than two steps as in mammals.
authors.affiliation: Laboratory of Biological Chemistry, University of Paris VI, France.
authors.forename: J
authors.initials: J
authors.lastname: Chauvet
authors.forename: G
authors.initials: G
authors.lastname: Michel
authors.forename: M T
authors.initials: MT
authors.lastname: Chauvet
authors.forename: R
authors.initials: R
authors.lastname: Acher
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001127:Arginine Vasopressin; D005075:Biological Evolution; D002417:Cattle; D006020:Glycopeptides; D008969:Molecular Sequence Data; D009481:Neurophysins; D010121:Oxytocin; D011487:Protein Conformation; D011498:Protein Precursors; D011893:Rana esculenta; D012689:Sequence Homology, Nucleic Acid; D014667:Vasopressins
chemical_list: D006020:Glycopeptides; D009481:Neurophysins; D011498:Protein Precursors; C048197:copeptins; D014667:Vasopressins; D001127:Arginine Vasopressin; D010121:Oxytocin