title: Overexpression of wheat alternative oxidase gene Waox1a alters respiration capacity and response to reactive oxygen species under low temperature in transgenic Arabidopsis.
abstract: Under low temperature conditions, the cytochrome pathway of respiration is repressed and reactive oxygen species (ROS) are produced in plants. Mitochondrial alternative oxidase (AOX) is the terminal oxidase responsible for the cyanide-insensitive and salicylhydroxamic acid-sensitive respiration. To study functions of wheat AOX genes under low temperature, we produced transgenic Arabidopsis by introducing Waox1a expressed under control of the cauliflower mosaic virus (CaMV) 35S promoter in Arabidopsis thaliana. The enhancement of endogenous AOX1a expression via low temperature stress was delayed in the transgenic Arabidopsis. Recovery of the total respiration activity under low temperature occurred more rapidly in the transgenic plants than in the wild-type plants due to a constitutively increased alternative pathway capacity. Levels of ROS decreased in the transgenic plants under low temperature stress. These results support the hypothesis that AOX alleviates oxidative stress when the cytochrome pathway of respiration is inhibited under abiotic stress conditions.
authors.affiliation: Laboratory of Plant Genetics, Faculty of Agriculture, and Graduate School of Science and Technology, Kobe University, Kobe, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Sugie
authors.forename: Nayden
authors.initials: N
authors.lastname: Naydenov
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Mizuno
authors.forename: Chiharu
authors.initials: C
authors.lastname: Nakamura
authors.forename: Shigeo
authors.initials: S
authors.lastname: Takumi
mesh_terms: D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics*; D019069:Cell Respiration / Q000502:physiology; D003080:Cold Temperature; D024101:Mitochondrial Proteins; D010088:Oxidoreductases / Q000235:genetics*; D010940:Plant Proteins; D030821:Plants, Genetically Modified; D017382:Reactive Oxygen Species / Q000378:metabolism*; D014908:Triticum / Q000201:enzymology* / Q000235:genetics*; D000099188:Alternative Oxidase
chemical_list: D024101:Mitochondrial Proteins; D010088:Oxidoreductases; D010940:Plant Proteins; D017382:Reactive Oxygen Species; D000099188:Alternative Oxidase