title: Responses of Populus trichocarpa galactinol synthase genes to abiotic stresses.
abstract: Galactinol synthase (GolS; EC 2.4.1.123) is a member of the glycosyltransferase eight family that catalyzes the first step in the biosynthesis pathway of the raffinose family of oligosaccharides (RFOs). The accumulation of RFOs in response to abiotic stress indicates a role for RFOs in stress adaptation. To obtain information on the roles of RFOs in abiotic stress adaptation in trees, we investigated the expression patterns of nine Populus trichocarpa GolS (PtrGolS) genes with special reference to stress responses. PtrGolS genes were differentially expressed in different organs, and the expressions of PtrGolS4 and PtrGolS6 were relatively high in all tested organs. The expression levels of all PtrGolS genes, except PtrGolS9, changed in response to abiotic stress in gene- and stress-type-specific manners. Moreover, short- and long-term stress treatments revealed that induction of PtrGolS by salt stress is obvious only in the early period of treatment (within 24 h), whereas water-deficit stress treatments continued to upregulate PtrGolS gene expression after two days of treatment, in addition to induction within 24 h of treatment. Consistent with these expression patterns, the galactinol content in leaves increased after four days of drought stress, but not under salt stress. Our findings suggest divergent roles for PtrGolS genes in abiotic stress responses in poplars.
authors.affiliation: Key Laboratory of Forest Genetics and Biotechnology, Ministry of Education, Nanjing Forestry University, Nanjing, 210037, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Zhou
authors.forename: Yang
authors.initials: Y
authors.lastname: Yang
authors.forename: Juan
authors.initials: J
authors.lastname: Yu
authors.forename: Like
authors.initials: L
authors.lastname: Wang
authors.forename: Xiang
authors.initials: X
authors.lastname: Yu
authors.forename: Misato
authors.initials: M
authors.lastname: Ohtani
authors.forename: Miyako
authors.initials: M
authors.lastname: Kusano
authors.forename: Kazuki
authors.initials: K
authors.lastname: Saito
authors.forename: Taku
authors.initials: T
authors.lastname: Demura
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhuge
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D004187:Disaccharides / Q000032:analysis / Q000378:metabolism; D055864:Droughts; D005700:Galactosyltransferases / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000032:analysis / Q000378:metabolism; D009928:Organ Specificity; D010802:Phylogeny; D010937:Plant Growth Regulators / Q000494:pharmacology; D018515:Plant Leaves / Q000187:drug effects / Q000201:enzymology / Q000235:genetics / Q000502:physiology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified; D032107:Populus / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics / Q000502:physiology; D011401:Promoter Regions, Genetic / Q000235:genetics; D011887:Raffinose / Q000032:analysis / Q000378:metabolism; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D012965:Sodium Chloride / Q000494:pharmacology; D013312:Stress, Physiological
chemical_list: D004187:Disaccharides; D009844:Oligosaccharides; D010937:Plant Growth Regulators; D010940:Plant Proteins; C013536:6 beta-galactinol; D012965:Sodium Chloride; D005700:Galactosyltransferases; C096645:inositol 1-alpha-galactosyltransferase; D011887:Raffinose