title: Spermine is not essential for survival of Arabidopsis.
abstract: Spermine is the final product of the polyamine biosynthetic pathway and is ubiquitously present in most organisms. The genome of Arabidopsis thaliana has two genes encoding spermine synthase: ACAULIS5 (ACL5), whose loss-of-function mutants show a severe defect in stem elongation, and SPMS. In order to elucidate the function of spermine in plants, we isolated a T-DNA insertion mutant of the SPMS gene. Free and conjugated spermine levels in the mutant, designated spms-1, were significantly decreased compared with those in the wild-type, but no obvious morphological phenotype was observed in spms-1 plants. We further confirmed that acl5-1 spms-1 double mutants contained no spermine. Surprisingly, acl5-1 spms-1 was fully as viable as the wild-type and showed no phenotype except for the reduced stem growth due to acl5-1. These results indicate that spermine is not essential for survival of Arabidopsis, at least under normal growth conditions.
authors.affiliation: Division of Biological Sciences, Graduate School of Science, Hokkaido University, 060-0810, Sapporo, Japan.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Imai
authors.forename: Takashi
authors.initials: T
authors.lastname: Akiyama
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Kato
authors.forename: Shusei
authors.initials: S
authors.lastname: Sato
authors.forename: Satoshi
authors.initials: S
authors.lastname: Tabata
authors.forename: Kotaro T
authors.initials: KT
authors.lastname: Yamamoto
authors.forename: Taku
authors.initials: T
authors.lastname: Takahashi
mesh_terms: D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics / Q000254:growth & development*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D018744:DNA, Plant / Q000032:analysis / Q000235:genetics; D017343:Genes, Plant; D018745:Genome, Plant; D016254:Mutagenesis, Insertional; D010641:Phenotype; D011073:Polyamines / Q000032:analysis; D012313:RNA / Q000032:analysis; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D036226:Seedlings / Q000737:chemistry; D013096:Spermine / Q000502:physiology*; D013097:Spermine Synthase / Q000235:genetics* / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D018744:DNA, Plant; D011073:Polyamines; D011994:Recombinant Proteins; D013096:Spermine; D012313:RNA; D013097:Spermine Synthase