title: Characterization of spermidine synthase and spermine synthase--The polyamine-synthetic enzymes that induce early flowering in Gentiana triflora.
abstract: Polyamines are essential for several living processes in plants. However, regulatory mechanisms of polyamines in herbaceous perennial are almost unknown. Here, we identified homologs of two Arabidopsis polyamine-synthetic enzymes, spermidine synthase (SPDS) and spermine synthase (SPMS) denoted as GtSPDS and GtSPMS, from the gentian plant, Gentiana triflora. Our results showed that recombinant proteins of GtSPDS and GtSPMS possessed SPDS and SPMS activities, respectively. The expression levels of GtSPDS and GtSPMS increased transiently during vegetative to reproductive growth phase and overexpression of the genes hastened flowering, suggesting that these genes are involved in flowering induction in gentian plants.
authors.affiliation: Department of Biological Science and Technology, Tokyo University of Science, 6-3-1 Niijuku, Katsushika, Tokyo 125-8585, Japan.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Imamura
authors.affiliation: Iwate Biotechnology Research Center, 22-174-4 Narita, Kitakami, Iwate 024-0003, Japan.
authors.forename: Kohei
authors.initials: K
authors.lastname: Fujita
authors.affiliation: Iwate Biotechnology Research Center, 22-174-4 Narita, Kitakami, Iwate 024-0003, Japan.
authors.forename: Keisuke
authors.initials: K
authors.lastname: Tasaki
authors.affiliation: Iwate Biotechnology Research Center, 22-174-4 Narita, Kitakami, Iwate 024-0003, Japan.
authors.forename: Atsumi
authors.initials: A
authors.lastname: Higuchi
authors.affiliation: Iwate Biotechnology Research Center, 22-174-4 Narita, Kitakami, Iwate 024-0003, Japan. Electronic address: h-takahashi@ibrc.or.jp.
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Takahashi
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics; D015317:Biogenic Polyamines / Q000096:biosynthesis*; D035264:Flowers / Q000254:growth & development*; D017343:Genes, Plant; D030012:Gentiana / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D008969:Molecular Sequence Data; D030821:Plants, Genetically Modified; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D011436:Spermidine Synthase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D013097:Spermine Synthase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: D015317:Biogenic Polyamines; D011994:Recombinant Proteins; D011436:Spermidine Synthase; D013097:Spermine Synthase
keywords: Gentiana triflora; Perennial herbaceous; Polyamine; Spermidine synthase; Spermine synthase