Cadmium toxicity in cultured tomato cells—Role of ethylene, proteases and oxidative stress in cell death signaling

Authors

  • Elena T. Iakimova,

    Corresponding author
    1. 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
    Search for more papers by this author
    • These authors contributed equally to this work.

  • Ernst J. Woltering,

    1. 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
    Search for more papers by this author
    • These authors contributed equally to this work.

  • Veneta M. Kapchina-Toteva,

    1. Department of Plant Physiology, Faculty of Biology, University of Sofia, 8 Dragan Tzankov Blvd., 1164 Sofia, Bulgaria
    Search for more papers by this author
    • These authors contributed equally to this work.

  • Frans J.M. Harren,

    1. Department of Molecular and Laser Physics, Institute for Molecules and Materials, Faculty of Science, Radboud University, Nijmegen, Toernooiveld 1, 6525 ED Nijmegen, The Netherlands
    Search for more papers by this author
  • Simona M. Cristescu

    1. Department of Molecular and Laser Physics, Institute for Molecules and Materials, Faculty of Science, Radboud University, Nijmegen, Toernooiveld 1, 6525 ED Nijmegen, The Netherlands
    Search for more papers by this author

Corresponding author. Tel.: +31 317475002; fax: +31 317475347. elena.iakimova@wur.nl

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.

Ancillary