title: A transient decrease in reactive oxygen species in roots leads to root hair deformation in the legume-rhizobia symbiosis.
abstract: * A possible role for reactive oxygen species (ROS) in root hair deformation in response to Nod factor (NF) was investigated using Medicago truncatula nodulation mutants, and an inhibitor and precursors of ROS. * In wild-type roots, ROS efflux transiently decreased approximately 1 h after NF treatment. Transcript accumulation of two NADPH oxidase homologs, respiratory burst oxidase homolog 2 (MtRBOH2) and MtRBOH3, also transiently decreased at 1 h. However, in the nonnodulating mutant Nod factor perception (nfp), transcript accumulation did not change. * Exogenous application of ROS prevented root hair swelling and branching induced by NF. When accumulation of ROS was prevented by diphenylene iodonium (DPI), NF did not induce root hair branching. Root treatment with DPI alone reduced ROS efflux and induced root hair tip swelling. Transient treatment of roots with DPI mimicked NF treatment and resulted in root hair branching in the absence of NF. A transient DPI treatment did not induce root hair branching in the nonlegumes Arabidopsis thaliana and tomato (Lycopersicon esculentum). * The results suggest a role for the transient reduction of ROS accumulation in governing NF-induced root hair deformation in legumes.
authors.affiliation: Department of Plant Biology, University of Minnesota, 250 Biological Sciences Building, 1445 Gortner Avenue, Saint Paul, MN 551088, USA.
authors.forename: Dasharath Prasad
authors.initials: DP
authors.lastname: Lohar
authors.forename: Sajeet
authors.initials: S
authors.lastname: Haridas
authors.forename: J Stephen
authors.initials: JS
authors.lastname: Gantt
authors.forename: Kathryn A
authors.initials: KA
authors.lastname: VandenBosch
mesh_terms: D017360:Arabidopsis / Q000187:drug effects / Q000254:growth & development / Q000382:microbiology; D015536:Down-Regulation; D007887:Fabaceae / Q000382:microbiology*; D000070116:Lotus / Q000187:drug effects / Q000254:growth & development / Q000382:microbiology; D018551:Solanum lycopersicum / Q000187:drug effects / Q000254:growth & development / Q000382:microbiology; D046913:Medicago truncatula / Q000166:cytology / Q000254:growth & development / Q000382:microbiology; D009154:Mutation; D019255:NADPH Oxidases / Q000235:genetics / Q000378:metabolism; D009861:Onium Compounds / Q000494:pharmacology; D018517:Plant Roots / Q000166:cytology / Q000254:growth & development / Q000382:microbiology*; D012333:RNA, Messenger / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000037:antagonists & inhibitors / Q000378:metabolism* / Q000494:pharmacology; D053204:Root Nodules, Plant / Q000235:genetics / Q000378:metabolism / Q000382:microbiology; D016962:Sinorhizobium meliloti / Q000502:physiology*; D013045:Species Specificity; D013559:Symbiosis / Q000235:genetics / Q000502:physiology
chemical_list: D009861:Onium Compounds; D012333:RNA, Messenger; D017382:Reactive Oxygen Species; C007517:diphenyleneiodonium; D019255:NADPH Oxidases