title: Mitochondrial behaviour in the early stages of ROS stress leading to cell death in Arabidopsis thaliana.
abstract: OBJECTIVE
  Reactive oxygen species (ROS) are involved in triggering cell death. To visualize mitochondrial behaviour under ROS stress, transgenic arabidopsis plants possessing mitochondrial-targeted GFP (S65T) were studied.
  
  
  METHODS
  Arabidopsis leaves were treated with ROS and ROS-inducing chemicals such as hydrogen peroxide, paraquat and menadione. Microscopic observations were carried out using a confocal laser scanning microscope system, and electrolyte leakage was also monitored.
  
  
  RESULTS
  After treatment, mitochondria showed morphological changes from a bacillus-like to a round shape. The size of mitochondria treated with H(2)O(2) decreased by half compared with controls. Concurrently, cytoplasmic streaming was blocked and mitochondria eventually swelled. Treatment of leaves with butanedione monoxime, an inhibitor of myosin ATPase, resulted in similar behaviour of mitochondria to that under ROS stress.
  
  
  CONCLUSIONS
  The results indicate that morphological changes of mitochondria and cessation of cytoplasmic streaming may interact, and this phenomenon is one of the features of ROS stress-induced cell death.
authors.affiliation: Institute of Molecular and Cellular Biosciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan.
authors.forename: Keiko
authors.initials: K
authors.lastname: Yoshinaga
authors.forename: Shin-ichi
authors.initials: S
authors.lastname: Arimura
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Niwa
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Tsutsumi
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Uchimiya
authors.forename: Maki
authors.initials: M
authors.lastname: Kawai-Yamada
mesh_terms: D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D016923:Cell Death; D003595:Cytoplasmic Streaming / Q000187:drug effects; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000494:pharmacology; D018613:Microscopy, Confocal; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism*; D009218:Myosins / Q000037:antagonists & inhibitors; D010269:Paraquat / Q000494:pharmacology; D018515:Plant Leaves / Q000187:drug effects / Q000378:metabolism; D030821:Plants, Genetically Modified; D017382:Reactive Oxygen Species / Q000378:metabolism*; D024483:Vitamin K 3 / Q000494:pharmacology
chemical_list: D017382:Reactive Oxygen Species; D049452:Green Fluorescent Proteins; D024483:Vitamin K 3; D006861:Hydrogen Peroxide; D009218:Myosins; D010269:Paraquat