title: Processing of multiple forms of preprosodefrin in the abdominal gland of the red-bellied newt Cynops pyrrhogaster: regional and individual differences in preprosodefrin gene expression.
abstract: Peptides derived from the post-translational processing of preprosodefrin were isolated from an extract of the abdominal glands of male red-bellied newts Cynops pyrrhogaster obtained 5 months prior to the onset of the breeding season. Structural characterization of the peptides showed that the pheromone sodefrin (SIPSKDALLK) is stored in a biologically inactive COOH-terminally extended form (SIPSKDALLKISA). It follows, therefore, that the activation of a protease that cleaves at a Lys-Ile bond to generate the active pheromone must occur by the time of onset of reproductive behavior. Additional peptides (representing preprosodefrin-(146-175)-peptide and preprosodefrin-(159-173)-peptide), that are derived from the precursor by cleavage at monobasic and dibasic processing sites, were also purified from the extract. The isolation of paralogs of these peptides, including an inactive COOH-terminally extended form of [Asn10]sodefrin, provides evidence for the expression of multiple genes encoding preprosodefrin. PCR products derived from total RNAs from the abdominal gland of individual newts collected from three different regions of Japan were analyzed. The data confirm the existence of multiple genes encoding sodefrin and its variants whose expression varied according to the individuals and the regions. However, genes encoding sodefrin were found to be expressed in all the specimens sampled.
authors.affiliation: Department of Biology, School of Education, Waseda University, Nishiwaseda 1-6-1, Shinjuku-ku, Tokyo 169-8050, Japan.
authors.forename: Takeo
authors.initials: T
authors.lastname: Iwata
authors.forename: J Michael
authors.initials: JM
authors.lastname: Conlon
authors.forename: Tomoaki
authors.initials: T
authors.lastname: Nakada
authors.forename: Fumiyo
authors.initials: F
authors.lastname: Toyoda
authors.forename: Kazutoshi
authors.initials: K
authors.lastname: Yamamoto
authors.forename: Sakae
authors.initials: S
authors.lastname: Kikuyama
mesh_terms: D034841:Abdominal Cavity; D000595:Amino Acid Sequence; D000818:Animals; D002850:Chromatography, Gel; D018076:DNA, Complementary / Q000378:metabolism; D008297:Male; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry / Q000378:metabolism*; D010675:Pheromones / Q000737:chemistry; D016133:Polymerase Chain Reaction; D011498:Protein Precursors / Q000737:chemistry* / Q000378:metabolism; D011499:Protein Processing, Post-Translational; D017434:Protein Structure, Tertiary; D012313:RNA / Q000378:metabolism; D012455:Salamandridae; D017386:Sequence Homology, Amino Acid
chemical_list: D018076:DNA, Complementary; D010455:Peptides; D010675:Pheromones; D011498:Protein Precursors; D012313:RNA