title: Altered lignin structure and resistance to pathogens in spi 2-expressing tobacco plants.
abstract: The physiological role of the Norway spruce [ Picea abies (L.) Karst.] spi 2 gene, encoding a defense-related cationic peroxidase was examined in transgenic tobacco (Nicotiana tabacum L.). Expression of spi 2, under control of the 35S promoter, in tobacco plants resulted in higher total peroxidase activities. The phenotype of the spi 2-transformed lines was normal. The spi 2-transformed lines displayed lignin levels similar to levels in the control line, but with some alteration in lignin histochemistry and structure. These changes were associated with reduced flexibility of the tobacco stems. The defense against pathogenic microorganisms was altered in the transgenic tobacco plants compared with control plants. High peroxidase activities increased the susceptibility to the pathogenic oomycete Phytophthora parasitica var. nicotianae, but increased the ability of the tobacco plants to suppress growth of the pathogenic bacterium Erwinia carotovora.
authors.affiliation: Department of Forest Genetics, Swedish University of Agricultural Sciences, Uppsala, Sweden.
authors.forename: Malin
authors.initials: M
authors.lastname: Elfstrand
authors.forename: Folke
authors.initials: F
authors.lastname: Sitbon
authors.forename: Catherine
authors.initials: C
authors.lastname: Lapierre
authors.forename: Arnaud
authors.initials: A
authors.lastname: Bottin
authors.forename: Sara
authors.initials: S
authors.lastname: von Arnold
mesh_terms: D018076:DNA, Complementary / Q000235:genetics; D018506:Gene Expression Regulation, Plant; D006651:Histocytochemistry; D007113:Immunity, Innate; D008031:Lignin / Q000737:chemistry / Q000378:metabolism*; D016973:Pectobacterium carotovorum / Q000254:growth & development / Q000276:immunology; D009195:Peroxidase / Q000378:metabolism; D010544:Peroxidases / Q000235:genetics* / Q000502:physiology; D010838:Phytophthora / Q000254:growth & development / Q000276:immunology; D028222:Picea / Q000235:genetics* / Q000502:physiology; D010935:Plant Diseases / Q000382:microbiology; D010940:Plant Proteins; D018517:Plant Roots / Q000502:physiology; D018547:Plant Stems / Q000502:physiology; D030821:Plants, Genetically Modified; D014026:Nicotiana / Q000235:genetics* / Q000382:microbiology
chemical_list: D018076:DNA, Complementary; D010940:Plant Proteins; D008031:Lignin; D010544:Peroxidases; C437068:spruce pathogen-induced 2 peroxidase; D009195:Peroxidase