title: Initiation of runaway cell death in an Arabidopsis mutant by extracellular superoxide.
abstract: Reactive oxygen intermediates (ROIs) regulate apoptosis during normal development and disease in animals. ROIs are also implicated in hypersensitive resistance responses of plants against pathogens. Arabidopsis lsd1 mutants exhibited impaired control of cell death in the absence of pathogen and could not control the spread of cell death once it was initiated. Superoxide was necessary and sufficient to initiate lesion formation; it accumulated before the onset of cell death and subsequently in live cells adjacent to spreading lsd1 lesions. Thus, runaway cell death seen in lsd1 plants reflected abnormal accumulation of superoxide and lack of responsiveness to signals derived from it.
authors.affiliation: Max-Delbrück Laboratory, Carl von Linné Weg 10, 50829 Köln, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Jabs
authors.forename: R A
authors.initials: RA
authors.lastname: Dietrich
authors.forename: J L
authors.initials: JL
authors.lastname: Dangl
mesh_terms: D017209:Apoptosis; D017360:Arabidopsis / Q000166:cytology* / Q000235:genetics / Q000378:metabolism; D002462:Cell Membrane / Q000201:enzymology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D005982:Glutathione Transferase / Q000235:genetics / Q000378:metabolism; D009154:Mutation; D009247:NADH, NADPH Oxidoreductases / Q000037:antagonists & inhibitors / Q000378:metabolism; D019255:NADPH Oxidases; D009861:Onium Compounds / Q000494:pharmacology; D010544:Peroxidases / Q000235:genetics / Q000378:metabolism; D018515:Plant Leaves / Q000166:cytology / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D018749:RNA, Plant / Q000235:genetics / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D013482:Superoxide Dismutase / Q000235:genetics; D013481:Superoxides / Q000378:metabolism*
chemical_list: D004791:Enzyme Inhibitors; D009861:Onium Compounds; D012333:RNA, Messenger; D018749:RNA, Plant; D017382:Reactive Oxygen Species; D013481:Superoxides; C007517:diphenyleneiodonium; D010544:Peroxidases; D013482:Superoxide Dismutase; D009247:NADH, NADPH Oxidoreductases; D019255:NADPH Oxidases; D005982:Glutathione Transferase