title: Aluminum induces oxidative stress genes in Arabidopsis thaliana.
abstract: Changes in gene expression induced by toxic levels of Al were characterized to investigate the nature of Al stress. A cDNA library was constructed from Arabidopsis thaliana seedlings treated with Al for 2 h. We identified five cDNA clones that showed a transient induction of their mRNA levels, four cDNA clones that showed a longer induction period, and two down-regulated genes. Expression of the four long-term-induced genes remained at elevated levels for at least 48 h. The genes encoded peroxidase, glutathione-S-transferase, blue copper-binding protein, and a protein homologous to the reticuline:oxygen oxidoreductase enzyme. Three of these genes are known to be induced by oxidative stresses and the fourth is induced by pathogen treatment. Another oxidative stress gene, superoxide dismutase, and a gene for Bowman-Birk protease inhibitor were also induced by Al in A. thaliana. These results suggested that Al treatment of Arabidopsis induces oxidative stress. In confirmation of this hypothesis, three of four genes induced by Al stress in A. thaliana were also shown to be induced by ozone. Our results demonstrate that oxidative stress is an important component of the plant's reaction to toxic levels of Al.
authors.affiliation: School of Biological Sciences, University of Auckland, New Zealand.
authors.forename: K D
authors.initials: KD
authors.lastname: Richards
authors.forename: E J
authors.initials: EJ
authors.lastname: Schott
authors.forename: Y K
authors.initials: YK
authors.lastname: Sharma
authors.forename: K R
authors.initials: KR
authors.lastname: Davis
authors.forename: R C
authors.initials: RC
authors.lastname: Gardner
mesh_terms: D000534:Alum Compounds / Q000494:pharmacology*; D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D029681:Arabidopsis Proteins; D002352:Carrier Proteins / Q000096:biosynthesis; D004790:Enzyme Induction; D018506:Gene Expression Regulation, Plant / Q000187:drug effects* / Q000502:physiology; D005982:Glutathione Transferase / Q000096:biosynthesis; D018527:Hydroponics; D007700:Kinetics; D018384:Oxidative Stress / Q000187:drug effects / Q000235:genetics*; D010126:Ozone / Q000494:pharmacology; D010544:Peroxidases / Q000096:biosynthesis; D010940:Plant Proteins / Q000096:biosynthesis; D012333:RNA, Messenger / Q000096:biosynthesis; D013482:Superoxide Dismutase / Q000096:biosynthesis; D014158:Transcription, Genetic / Q000187:drug effects; D014361:Trypsin Inhibitors / Q000096:biosynthesis
chemical_list: D000534:Alum Compounds; D029681:Arabidopsis Proteins; C085507:BCB protein, Arabidopsis; D002352:Carrier Proteins; D010940:Plant Proteins; D012333:RNA, Messenger; D014361:Trypsin Inhibitors; C023548:copper-binding protein; C041524:aluminum sulfate; D010126:Ozone; D010544:Peroxidases; D013482:Superoxide Dismutase; D005982:Glutathione Transferase