title: Gene expression and sensitivity in response to copper stress in rice leaves.
abstract: Gene expression in response to Cu stress in rice leaves was quantified using DNA microarray (Agilent 22K Rice Oligo Microarray) and real-time PCR technology. Rice plants were grown in hydroponic solutions containing 0.3 (control), 10, 45, or 130 microM of CuCl(2), and Cu accumulation and photosynthesis inhibition were observed in leaves within 1 d of the start of treatment. Microarray analysis flagged 305 Cu-responsive genes, and their expression profile showed that a large proportion of general and defence stress response genes are up-regulated under excess Cu conditions, whereas photosynthesis and transport-related genes are down-regulated. The Cu sensitivity of each Cu-responsive gene was estimated by the median effective concentration value (EC50) and the range of fold-changes (F) under the highest (130 microM) Cu conditions (|log(2)F|(130)). Our results indicate that defence-related genes involved in phytoalexin and lignin biosynthesis were the most sensitive to Cu, and that plant management of abiotic and pathogen stresses has overlapping components, possibly including signal transduction.
authors.affiliation: RIKEN Plant Science Center, Suehiro 1-7-22, Tsurumi, Yokohama 230-0045, Japan.
authors.forename: Emi
authors.initials: E
authors.lastname: Sudo
authors.forename: Misao
authors.initials: M
authors.lastname: Itouga
authors.forename: Kayo
authors.initials: K
authors.lastname: Yoshida-Hatanaka
authors.forename: Yoshiro
authors.initials: Y
authors.lastname: Ono
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Sakakibara
mesh_terms: D003300:Copper / Q000378:metabolism* / Q000494:pharmacology; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D020411:Oligonucleotide Array Sequence Analysis; D012275:Oryza / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D010788:Photosynthesis / Q000187:drug effects; D018515:Plant Leaves / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D010940:Plant Proteins; D003300:Copper