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Cancer Cell death Cell cycle Cytoskeleton Exo/endocytosis Differentiation Division Organelles Signalling Stem cells Trafficking
Cell Biology International (2008) 32, 1521–1529 (Printed in Great Britain)
Cadmium toxicity in cultured tomato cells – Role of ethylene, proteases and oxidative stress in cell death signaling
Elena T. Iakimovaa*1, Ernst J. Wolteringa1, Veneta M. Kapchina‑Totevab1, Frans J.M. Harrenc and Simona M. Cristescuc
aWageningen 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
bDepartment of Plant Physiology, Faculty of Biology, University of Sofia, 8 Dragan Tzankov Blvd., 1164 Sofia, Bulgaria
cDepartment of Molecular and Laser Physics, Institute for Molecules and Materials, Faculty of Science, Radboud University, Nijmegen, Toernooiveld 1, 6525 ED Nijmegen, The Netherlands


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 CdSO4 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.


Key words: Cadmium, Ethylene, Lycopersicon esculentum Mill, Oxidative stress, Proteolysis.

1These authors contributed equally to this work.

*Corresponding author. Tel.: +31 317475002; fax: +31 317475347.


Received 14 March 2008/15 May 2008; accepted 19 August 2008

doi:10.1016/j.cellbi.2008.08.021


ISSN Print: 1065-6995
ISSN Electronic: 1095-8355
Published by Portland Press Limited on behalf of the International Federation for Cell Biology (IFCB)