title: The expression pattern of the Picea glauca Defensin 1 promoter is maintained in Arabidopsis thaliana, indicating the conservation of signalling pathways between angiosperms and gymnosperms.
abstract: A 1149 bp genomic fragment corresponding to the 5' non-coding region of the PgD1 (Picea glauca Defensin 1) gene was cloned, characterized, and compared with all Arabidopsis thaliana defensin promoters. The cloned fragment was found to contain several motifs specific to defence or hormonal response, including a motif involved in the methyl jasmonate reponse, a fungal elicitor responsive element, and TC-rich repeat cis-acting element involved in defence and stress responsiveness. A functional analysis of the PgD1 promoter was performed using the uidA (GUS) reporter system in stably transformed Arabidopsis and white spruce plants. The PgD1 promoter was responsive to jasmonic acid (JA), to infection by fungus and to wounding. In transgenic spruce embryos, GUS staining was clearly restricted to the shoot apical meristem. In Arabidopsis, faint GUS coloration was observed in leaves and flowers and a strong blue colour was observed in guard cells and trichomes. Transgenic Arabidopsis plants expressing the PgD1::GUS construct were also infiltrated with the hemibiotrophic pathogen Pseudomonas syringae pv. tomato DC3000. It caused a suppression of defensin expression probably resulting from the antagonistic relationship between the pathogen-stimulated salicylic acid pathway and the jasmonic acid pathway. It is therefore concluded that the PgD1 promoter fragment cloned appears to contain most if not all the elements for proper PgD1 expression and that these elements are also recognized in Arabidopsis despite the phylogenetic and evolutionary differences that separates them.
authors: Natural Resources Canada, Canadian Forest Service, Laurentian Forestry Centre, 1055 du P.E.P.S., PO Box 10380, Stn. Sainte-Foy, Québec, QC, G1V 4C7, Canada.
authors: Hugo
authors: H
authors: Germain
authors: Denis
authors: D
authors: Lachance
authors: Gervais
authors: G
authors: Pelletier
authors: Carl Gunnar
authors: CG
authors: Fossdal
authors: Halvor
authors: H
authors: Solheim
authors: Armand
authors: A
authors: Séguin
mesh_terms: D017360:Arabidopsis / Q000166:cytology / Q000235:genetics* / Q000502:physiology; D032462:Cycadopsida / Q000166:cytology / Q000235:genetics / Q000502:physiology; D003517:Cyclopentanes / Q000378:metabolism; D018744:DNA, Plant / Q000235:genetics; D023082:Defensins / Q000235:genetics* / Q000378:metabolism; D018506:Gene Expression Regulation, Plant / Q000235:genetics; D017930:Genes, Reporter; D019684:Magnoliopsida / Q000166:cytology / Q000235:genetics / Q000502:physiology; D059372:Nucleotide Motifs; D054883:Oxylipins / Q000378:metabolism; D010802:Phylogeny; D028222:Picea / Q000166:cytology / Q000235:genetics* / Q000502:physiology; D057865:Plant Immunity; D018515:Plant Leaves / Q000166:cytology / Q000235:genetics / Q000502:physiology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D018520:Plant Shoots / Q000166:cytology / Q000235:genetics / Q000502:physiology; D030821:Plants, Genetically Modified; D011401:Promoter Regions, Genetic / Q000235:genetics*; D044224:Pseudomonas syringae / Q000502:physiology; D020156:Salicylic Acid / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology; D013489:Suppression, Genetic / Q000235:genetics
chemical_list: D003517:Cyclopentanes; D018744:DNA, Plant; D023082:Defensins; D054883:Oxylipins; D010940:Plant Proteins; C011006:jasmonic acid; D020156:Salicylic Acid