title: Structure, expression profile and subcellular localisation of four different sucrose synthase genes from barley.
abstract: Genes encoding two new isoforms of sucrose synthase from barley, HvSs3 and HvSs4, have been characterised and their expression patterns compared with those previously described for HvSs1 and HvSs2, in different organs and during seed maturation and germination. Their response to several abiotic stimuli has also been investigated in leaves: HvSs1 is up-regulated by anoxia and HvSs3 by water deprivation while no response is observed to 150 mM NaCl treatment; HvSs1 and HvSs3 are also induced by cold temperatures. Using translational fusions and transient expression analyses, the four isozymes have been localised not only to the cytoplasm but also along several cytoplasmic tracks and at the inner side of the cell membrane; besides, HvSS1 is also associated with mitochondria, a localisation that has been predicted in silico with the TargetP and Predotar programmes. These data suggest distinct although partially overlapping roles, for the four barley sucrose synthase isoforms, in the channelling of carbon towards different metabolic pathways within the cell.
authors.affiliation: Centro de Biotecnología y Genómica de Plantas (UPM-INIA), Escuela Técnica Superior de Ingenieros Agrónomos, Campus de Montegancedo, Universidad Politécnica de Madrid, Pozuelo de Alarcón, Madrid, 28223, Spain. cristina.barrero@upm.es
authors.forename: Cristina
authors.initials: C
authors.lastname: Barrero-Sicilia
authors.forename: Sara
authors.initials: S
authors.lastname: Hernando-Amado
authors.forename: Pablo
authors.initials: P
authors.lastname: González-Melendi
authors.forename: Pilar
authors.initials: P
authors.lastname: Carbonero
mesh_terms: D000693:Anaerobiosis; D002462:Cell Membrane / Q000378:metabolism; D003080:Cold Temperature; D003593:Cytoplasm / Q000378:metabolism; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D055864:Droughts; D018506:Gene Expression Regulation, Plant / Q000235:genetics; D018525:Germination; D005964:Glucosyltransferases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001467:Hordeum / Q000235:genetics* / Q000378:metabolism* / Q000648:ultrastructure; D007527:Isoenzymes / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D010802:Phylogeny; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D018749:RNA, Plant / Q000235:genetics / Q000302:isolation & purification; D011993:Recombinant Fusion Proteins; D012639:Seeds / Q000235:genetics / Q000378:metabolism; D012965:Sodium Chloride / Q000494:pharmacology; D013312:Stress, Physiological; D013395:Sucrose / Q000378:metabolism; D014867:Water / Q000378:metabolism
chemical_list: D018076:DNA, Complementary; D007527:Isoenzymes; D010940:Plant Proteins; D018749:RNA, Plant; D011993:Recombinant Fusion Proteins; D014867:Water; D012965:Sodium Chloride; D013395:Sucrose; D005964:Glucosyltransferases; C022699:sucrose synthase