title: Spermine modulates the expression of two probable polyamine transporter genes and determines growth responses to cadaverine in Arabidopsis.
abstract: Two genes, LAT1 and OCT1 , are likely to be involved in polyamine transport in Arabidopsis. Endogenous spermine levels modulate their expression and determine the sensitivity to cadaverine. Arabidopsis spermine (Spm) synthase (SPMS) gene-deficient mutant was previously shown to be rather resistant to the diamine cadaverine (Cad). Furthermore, a mutant deficient in polyamine oxidase 4 gene, accumulating about twofold more of Spm than wild type plants, showed increased sensitivity to Cad. It suggests that endogenous Spm content determines growth responses to Cad in Arabidopsis thaliana. Here, we showed that Arabidopsis seedlings pretreated with Spm absorbs more Cad and has shorter root growth, and that the transgenic Arabidopsis plants overexpressing the SPMS gene are hypersensitive to Cad, further supporting the above idea. The transgenic Arabidopsis overexpressing L-Amino acid Transporter 1 (LAT1) absorbed more Cad and showed increased Cad sensitivity, suggesting that LAT1 functions as a Cad importer. Recently, other research group reported that Organic Cation Transporter 1 (OCT1) is a causal gene which determines the Cad sensitivity of various Arabidopsis accessions. Furthermore, their results suggested that OCT1 is involved in Cad efflux. Thus we monitored the expression of OCT1 and LAT1 during the above experiments. Based on the results, we proposed a model in which the level of Spm content modulates the expression of OCT1 and LAT1, and determines Cad sensitivity of Arabidopsis.
authors.affiliation: Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Aoba, Sendai, 980-8577, Japan.
authors.forename: G H M
authors.initials: GH
authors.lastname: Sagor
authors.affiliation: Biodiversity and Climate Research Center, Laboratory Center, Georg-Voigt-Str. 14-16, 60325, Frankfurt am Main, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Berberich
authors.affiliation: Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Aoba, Sendai, 980-8577, Japan.|Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Aramaki aza Aoba 6-3, Aoba, Sendai, 980-8578, Japan.
authors.forename: Seiji
authors.initials: S
authors.lastname: Kojima
authors.affiliation: Faculty of Pharmaceutical Sciences, Josai University, Sakado, Saitama, 350-0295, Japan.
authors.forename: Masaru
authors.initials: M
authors.lastname: Niitsu
authors.affiliation: Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Aoba, Sendai, 980-8577, Japan. kusano@ige.tohoku.ac.jp.
authors.forename: Tomonobu
authors.initials: T
authors.lastname: Kusano
mesh_terms: D017360:Arabidopsis / Q000187:drug effects / Q000254:growth & development* / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics / Q000502:physiology; D002103:Cadaverine / Q000494:pharmacology*; D027682:Cation Transport Proteins / Q000502:physiology; D018506:Gene Expression Regulation, Plant / Q000187:drug effects / Q000502:physiology; D017343:Genes, Plant / Q000235:genetics / Q000502:physiology; D027283:Large Neutral Amino Acid-Transporter 1 / Q000502:physiology; D026901:Membrane Transport Proteins / Q000502:physiology; D027702:Organic Cation Transporter 1 / Q000502:physiology; D030821:Plants, Genetically Modified / Q000502:physiology; D016133:Polymerase Chain Reaction; D013096:Spermine / Q000494:pharmacology*
chemical_list: D029681:Arabidopsis Proteins; D027682:Cation Transport Proteins; C000614717:LAT1 protein, Arabidopsis; D027283:Large Neutral Amino Acid-Transporter 1; D026901:Membrane Transport Proteins; C000614718:OCT1 protein, Arabidopsis; D027702:Organic Cation Transporter 1; D013096:Spermine; D002103:Cadaverine
keywords: Arabidopsis; Cadaverine response; L-Amino acid Transporter 1; Organic Cation Transporter 1; Polyamine; Spermine