title: Cadmium toxicity in cultured tomato cells--role of ethylene, proteases and oxidative stress in cell death signaling.
abstract: Our aim was to investigate the ability of cadmium to induce programmed cell death in tomato suspension cells and to determine the involvement of proteolysis, oxidative stress and ethylene. Tomato suspension cells were exposed to treatments with CdSO(4) and cell death was calculated after fluorescein diacetate staining of the living cells. Ethylene was measured in a flow-through system using a laser-driven photo acoustic detector; hydrogen peroxide was determined by chemiluminescence in a ferricyanide-catalysed oxidation of luminol. We have demonstrated that cadmium induces cell death in tomato suspension cells involving caspase-like proteases, indicating that programmed cell death took place. Using range of inhibitors, we found that cysteine and serine peptidases, oxidative stress, calcium and ethylene are players in the cadmium-induced cell death signaling. Cadmium-induced cell death in tomato suspension cells exhibits morphological and biochemical similarities to plant hypersensitive response and to cadmium effects in animal systems.
authors.affiliation: Wageningen University & Research Centre, Department of Horticultural Supply Chains (HSC) and Agrotechnology and Food Science Group (AFSG) P.O. Box 17, 6700 AA Wageningen, The Netherlands. elena.iakimova@wur.nl
authors.forename: Elena T
authors.initials: ET
authors.lastname: Iakimova
authors.forename: Ernst J
authors.initials: EJ
authors.lastname: Woltering
authors.forename: Veneta M
authors.initials: VM
authors.lastname: Kapchina-Toteva
authors.forename: Frans J M
authors.initials: FJ
authors.lastname: Harren
authors.forename: Simona M
authors.initials: SM
authors.lastname: Cristescu
mesh_terms: D017209:Apoptosis / Q000187:drug effects* / Q000502:physiology; D019187:Cadmium Compounds / Q000633:toxicity*; D002118:Calcium / Q000378:metabolism; D020169:Caspases / Q000187:drug effects / Q000378:metabolism; D002478:Cells, Cultured; D005030:Ethylenes / Q000378:metabolism*; D008163:Luminescent Measurements / Q000379:methods; D018551:Solanum lycopersicum / Q000187:drug effects* / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects* / Q000502:physiology; D010447:Peptide Hydrolases / Q000187:drug effects* / Q000378:metabolism; D010777:Photochemistry / Q000379:methods; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D013431:Sulfates / Q000633:toxicity
chemical_list: D019187:Cadmium Compounds; D005030:Ethylenes; D013431:Sulfates; C036216:ethylene; C037123:cadmium sulfate; D010447:Peptide Hydrolases; D020169:Caspases; D002118:Calcium