title: Ethylene signalling is mediating the early cadmium-induced oxidative challenge in Arabidopsis thaliana.
abstract: Cadmium (Cd) induces the generation of reactive oxygen species (ROS) and stimulates ethylene biosynthesis. The phytohormone ethylene is a regulator of many developmental and physiological plant processes as well as stress responses. Previous research indicated various links between ethylene signalling and oxidative stress. Our results support a correlation between the Cd-induced oxidative challenge and ethylene signalling in Arabidopsis thaliana leaves. The effects of 24 or 72 h exposure to 5 μM Cd on plant growth and several oxidative stress-related parameters were compared between wild-type (WT) and ethylene insensitive mutants (etr1-1, ein2-1, ein3-1). Cadmium-induced responses observed in WT plants were mainly affected in etr1-1 and ein2-1 mutants, of which the growth was less inhibited by Cd exposure as compared to WT and ein3-1 mutants. Both etr1-1 and ein2-1 showed a delayed response in the glutathione (GSH) metabolism, including GSH levels and transcript levels of GSH synthesising and recycling enzymes. Furthermore, the expression of different oxidative stress marker genes was significantly lower in Cd-exposed ein2-1 mutants, evidencing that ethylene signalling is involved in early responses to Cd stress. A model for the cross-talk between ethylene signalling and oxidative stress is proposed.
authors.affiliation: Centre for Environmental Sciences, Hasselt University, Agoralaan Building D, 3590 Diepenbeek, Belgium. Electronic address: kerim.schellingen@uhasselt.be.
authors.forename: Kerim
authors.initials: K
authors.lastname: Schellingen
authors.affiliation: Laboratory for Functional Plant Biology, Ghent University, Karel Lodewijk Ledeganckstraat 35, 9000 Ghent, Belgium. Electronic address: dominique.vanderstraeten@ugent.be.
authors.forename: Dominique
authors.initials: D
authors.lastname: Van Der Straeten
authors.affiliation: Centre for Environmental Sciences, Hasselt University, Agoralaan Building D, 3590 Diepenbeek, Belgium. Electronic address: tony.remans@uhasselt.be.
authors.forename: Tony
authors.initials: T
authors.lastname: Remans
authors.affiliation: Centre for Environmental Sciences, Hasselt University, Agoralaan Building D, 3590 Diepenbeek, Belgium. Electronic address: jaco.vangronsveld@uhasselt.be.
authors.forename: Jaco
authors.initials: J
authors.lastname: Vangronsveld
authors.affiliation: Centre for Environmental Sciences, Hasselt University, Agoralaan Building D, 3590 Diepenbeek, Belgium. Electronic address: els.keunen@uhasselt.be.
authors.forename: Els
authors.initials: E
authors.lastname: Keunen
authors.affiliation: Centre for Environmental Sciences, Hasselt University, Agoralaan Building D, 3590 Diepenbeek, Belgium. Electronic address: ann.cuypers@uhasselt.be.
authors.forename: Ann
authors.initials: A
authors.lastname: Cuypers
mesh_terms: D017360:Arabidopsis / Q000187:drug effects* / Q000378:metabolism; D002104:Cadmium / Q000633:toxicity*; D005030:Ethylenes / Q000378:metabolism*; D008954:Models, Biological; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D010937:Plant Growth Regulators / Q000378:metabolism*; D018515:Plant Leaves / Q000187:drug effects / Q000378:metabolism; D015398:Signal Transduction; D012989:Soil Pollutants / Q000633:toxicity*
chemical_list: D005030:Ethylenes; D010937:Plant Growth Regulators; D012989:Soil Pollutants; D002104:Cadmium; C036216:ethylene
keywords: Arabidopsis thaliana; Cadmium; Ethylene signalling; Glutathione; Oxidative stress