title: Cadmium effect on oxidative metabolism of pea (Pisum sativum L.) roots. Imaging of reactive oxygen species and nitric oxide accumulation in vivo.
abstract: Growth of pea (Pisum sativum L.) plants with 50 microM CdCl2 for 15 d produced a reduction in the number and length of lateral roots, and changes in structure of the principal roots affecting the xylem vessels. Cadmium induced a reduction in glutathione (GSH) and ascorbate (ASC) contents, and catalase (CAT), GSH reductase (GR) and guaiacol peroxidase (GPX) activities. CuZn-superoxide dismutase (SOD) activity was also diminished by the Cd treatment, although Mn-SOD was slightly increased. CAT and CuZn-SOD were down-regulated at transcriptional level, while Mn-SOD, Fe-SOD and GR were up-regulated. Analysis of reactive oxygen species (ROS) and nitric oxide (NO) levels by fluorescence and confocal laser microscopy (CLM) showed an over-accumulation of O2*- and H2O2, and a reduction in the NO content in lateral and principal roots. ROS overproduction was dependent on changes in intracellular Ca+2 content, and peroxidases and NADPH oxidases were involved. Cadmium also produced an increase in salicylic acid (SA), jasmonic acid (JA) and ethylene (ET) contents. The rise of ET and ROS, and the NO decrease are in accordance with senescence processes induced by Cd, and the increase of JA and SA could regulate the cellular response to cope with damages imposed by cadmium.
authors.affiliation: Departamento de Bioquimica, Biología Celular y Molecular de Plantas, Estación Experimental del Zaidin CSIC, Granada, Spain.
authors.forename: María
authors.initials: M
authors.lastname: Rodríguez-Serrano
authors.forename: María C
authors.initials: MC
authors.lastname: Romero-Puertas
authors.forename: Ana
authors.initials: A
authors.lastname: Zabalza
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Corpas
authors.forename: Manuel
authors.initials: M
authors.lastname: Gómez
authors.forename: Luis A
authors.initials: LA
authors.lastname: Del Río
authors.forename: Luisa M
authors.initials: LM
authors.lastname: Sandalio
mesh_terms: D000975:Antioxidants / Q000378:metabolism; D002104:Cadmium / Q000494:pharmacology*; D003517:Cyclopentanes / Q000378:metabolism; D005030:Ethylenes / Q000378:metabolism; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D006861:Hydrogen Peroxide / Q000378:metabolism; D018613:Microscopy, Confocal; D008969:Molecular Sequence Data; D009569:Nitric Oxide / Q000032:analysis / Q000378:metabolism*; D010084:Oxidation-Reduction / Q000187:drug effects; D018384:Oxidative Stress; D010100:Oxygen / Q000378:metabolism; D054883:Oxylipins; D018532:Pisum sativum / Q000033:anatomy & histology / Q000187:drug effects* / Q000378:metabolism; D018517:Plant Roots / Q000033:anatomy & histology / Q000187:drug effects / Q000502:physiology; D017382:Reactive Oxygen Species / Q000032:analysis / Q000378:metabolism*; D020156:Salicylic Acid / Q000378:metabolism; D015398:Signal Transduction
chemical_list: D000975:Antioxidants; D003517:Cyclopentanes; D005030:Ethylenes; D054883:Oxylipins; D017382:Reactive Oxygen Species; D002104:Cadmium; D009569:Nitric Oxide; C011006:jasmonic acid; C036216:ethylene; D006861:Hydrogen Peroxide; D020156:Salicylic Acid; D010100:Oxygen