title: EARLY RESPONSIVE TO DEHYDRATION 15, a negative regulator of abscisic acid responses in Arabidopsis.
abstract: EARLY RESPONSIVE TO DEHYDRATION 15 (ERD15) is rapidly induced in response to various abiotic and biotic stress stimuli in Arabidopsis (Arabidopsis thaliana). Modulation of ERD15 levels by overexpression or RNAi silencing altered the responsiveness of the transgenic plants to the phytohormone abscisic acid (ABA). Overexpression of ERD15 reduced the ABA sensitivity of Arabidopsis manifested in decreased drought tolerance and in impaired ability of the plants to increase their freezing tolerance in response to this hormone. In contrast, RNAi silencing of ERD15 resulted in plants that were hypersensitive to ABA and showed improved tolerance to both drought and freezing, as well as impaired seed germination in the presence of ABA. The modulation of ERD15 levels not only affected abiotic stress tolerance but also disease resistance: ERD15 overexpression plants showed improved resistance to the bacterial necrotroph Erwinia carotovora subsp. carotovora accompanied with enhanced induction of marker genes for systemic acquired resistance. We propose that ERD15 is a novel mediator of stress-related ABA signaling in Arabidopsis.
authors.affiliation: Viikki Biocenter, Department of Biological and Environmental Sciences, Division of Genetics, University of Helsinki, FIN-00014, Helsinki, Finland.
authors.forename: Tarja
authors.initials: T
authors.lastname: Kariola
authors.forename: Günter
authors.initials: G
authors.lastname: Brader
authors.forename: Elina
authors.initials: E
authors.lastname: Helenius
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.forename: Pekka
authors.initials: P
authors.lastname: Heino
authors.forename: E Tapio
authors.initials: ET
authors.lastname: Palva
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology*; D017360:Arabidopsis / Q000187:drug effects / Q000382:microbiology / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D005819:Genetic Markers; D018525:Germination / Q000187:drug effects; D007113:Immunity, Innate / Q000235:genetics; D016973:Pectobacterium carotovorum / Q000502:physiology; D010937:Plant Growth Regulators / Q000494:pharmacology*; D030821:Plants, Genetically Modified / Q000187:drug effects; D034622:RNA Interference; D012639:Seeds / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D015398:Signal Transduction; D013696:Temperature; D014867:Water / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; C441601:ERD15 protein, Arabidopsis; D005819:Genetic Markers; D010937:Plant Growth Regulators; D014867:Water; D000040:Abscisic Acid