title: PHYTOALEXIN DEFICIENT 4 affects reactive oxygen species metabolism, cell wall and wood properties in hybrid aspen (Populus tremula L. × tremuloides).
abstract: The phytoalexin deficient 4 (PAD4) gene in Arabidopsis thaliana (AtPAD4) is involved in the regulation of plant--pathogen interactions. The role of PAD4 in woody plants is not known; therefore, we characterized its function in hybrid aspen and its role in reactive oxygen species (ROS)-dependent signalling and wood development. Three independent transgenic lines with different suppression levels of poplar PAD expression were generated. All these lines displayed deregulated ROS metabolism, which was manifested by an increased H2O2 level in the leaves and shoots, and higher activities of manganese superoxide dismutase (MnSOD) and catalase (CAT) in the leaves in comparison to the wild-type plants. However, no changes in non-photochemical quenching (NPQ) between the transgenic lines and wild type were observed in the leaves. Moreover, changes in the ROS metabolism in the pad4 transgenic lines positively correlated with wood formation. A higher rate of cell division, decreased tracheid average size and numbers, and increased cell wall thickness were observed. The results presented here suggest that the Populus tremula × tremuloides PAD gene might be involved in the regulation of cellular ROS homeostasis and in the cell division--cell death balance that is associated with wood development.
authors.affiliation: Department of Plant Genetics, Breeding and Biotechnology, Warsaw University of Life Sciences, 02-776, Warszawa, Poland.|The Franciszek Górski Institute of Plant Physiology, Polish Academy of Sciences, 30-239, Kraków, Poland.
authors.forename: Ireneusz
authors.initials: I
authors.lastname: Ślesak
authors.affiliation: Department of Plant Genetics, Breeding and Biotechnology, Warsaw University of Life Sciences, 02-776, Warszawa, Poland.|The Franciszek Górski Institute of Plant Physiology, Polish Academy of Sciences, 30-239, Kraków, Poland.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Szechyńska-Hebda
authors.affiliation: Department of Plant Genetics, Breeding and Biotechnology, Warsaw University of Life Sciences, 02-776, Warszawa, Poland.
authors.forename: Halina
authors.initials: H
authors.lastname: Fedak
authors.affiliation: Department of Plant Genetics, Breeding and Biotechnology, Warsaw University of Life Sciences, 02-776, Warszawa, Poland.
authors.forename: Natalia
authors.initials: N
authors.lastname: Sidoruk
authors.affiliation: Department of Plant Genetics, Breeding and Biotechnology, Warsaw University of Life Sciences, 02-776, Warszawa, Poland.
authors.forename: Joanna
authors.initials: J
authors.lastname: Dąbrowska-Bronk
authors.affiliation: Department of Plant Genetics, Breeding and Biotechnology, Warsaw University of Life Sciences, 02-776, Warszawa, Poland.
authors.forename: Damian
authors.initials: D
authors.lastname: Witoń
authors.affiliation: Department of Plant Genetics, Breeding and Biotechnology, Warsaw University of Life Sciences, 02-776, Warszawa, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Rusaczonek
authors.affiliation: Department of Wood Science and Wood Preservation, Warsaw University of Life Sciences, 02-787, Warszawa, Poland.
authors.forename: Andrzej
authors.initials: A
authors.lastname: Antczak
authors.affiliation: Department of Wood Science and Wood Preservation, Warsaw University of Life Sciences, 02-787, Warszawa, Poland.
authors.forename: Michał
authors.initials: M
authors.lastname: Drożdżek
authors.affiliation: Department of Plant Genetics, Breeding and Biotechnology, Warsaw University of Life Sciences, 02-776, Warszawa, Poland.
authors.forename: Barbara
authors.initials: B
authors.lastname: Karpińska
authors.affiliation: Department of Plant Genetics, Breeding and Biotechnology, Warsaw University of Life Sciences, 02-776, Warszawa, Poland.
authors.forename: Stanisław
authors.initials: S
authors.lastname: Karpiński
mesh_terms: D002374:Catalase / Q000378:metabolism; D002473:Cell Wall / Q000378:metabolism; D002734:Chlorophyll / Q000378:metabolism; D000077194:Chlorophyll A; D018506:Gene Expression Regulation, Plant; D006824:Hybridization, Genetic; D008031:Lignin / Q000032:analysis; D018515:Plant Leaves / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D018520:Plant Shoots / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D030821:Plants, Genetically Modified; D032107:Populus / Q000235:genetics* / Q000254:growth & development / Q000502:physiology; D017382:Reactive Oxygen Species / Q000378:metabolism; D012717:Sesquiterpenes / Q000378:metabolism*; D013482:Superoxide Dismutase / Q000378:metabolism; D014934:Wood / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D000094162:Phytoalexins
chemical_list: D010940:Plant Proteins; D017382:Reactive Oxygen Species; D012717:Sesquiterpenes; D002734:Chlorophyll; D008031:Lignin; D002374:Catalase; D013482:Superoxide Dismutase; D000077194:Chlorophyll A; D000094162:Phytoalexins
keywords: cell death; phytoalexin deficiency; poplar wood development