title: Applied jasmonates accumulate extracellularly in tomato, but intracellularly in barley.
abstract: Jasmonic acid (JA) and its derivatives are well-characterized signaling molecules in plant defense and development, but the site of their localization within plant tissue is entirely unknown. To address the question whether applied JA accumulates extracellularly or intracellularly, leaves of tomato and barley were fed with 14C-labeled JA and the label was localized in cryofixed and lyophilized leaf tissues by microautoradiography. In tomato the radioactivity was detectable within the apoplast, but no label was found within the mesophyll cells. By contrast, in barley leaf tissues, radioactivity was detected within the mesophyll cells suggesting a cellular uptake of exogenously applied JA. JA, applied to leaves of both plants as in the labeling experiments, led in all leaf cells to the expression of JA-inducible genes indicating that the perception is completed by JA signal transduction.
authors.affiliation: Department of Plant Biology, Michigan State University, East Lansing, MI 48824-1312, USA.
authors.forename: Heike
authors.initials: H
authors.lastname: Bücking
authors.forename: Hella
authors.initials: H
authors.lastname: Förster
authors.forename: Irene
authors.initials: I
authors.lastname: Stenzel
authors.forename: Otto
authors.initials: O
authors.lastname: Miersch
authors.forename: Bettina
authors.initials: B
authors.lastname: Hause
mesh_terms: D001345:Autoradiography; D002250:Carbon Radioisotopes / Q000378:metabolism; D003517:Cyclopentanes / Q000008:administration & dosage / Q000494:pharmacology*; D018506:Gene Expression Regulation, Plant; D001467:Hordeum / Q000166:cytology / Q000187:drug effects*; D017403:In Situ Hybridization; D018551:Solanum lycopersicum / Q000166:cytology / Q000187:drug effects*; D054883:Oxylipins; D010937:Plant Growth Regulators / Q000494:pharmacology*; D018515:Plant Leaves / Q000166:cytology / Q000187:drug effects; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology
chemical_list: D002250:Carbon Radioisotopes; D003517:Cyclopentanes; D054883:Oxylipins; D010937:Plant Growth Regulators; D010940:Plant Proteins; D012333:RNA, Messenger; C011006:jasmonic acid