Regulation of the Rice NADPH Oxidase by Binding of Small GTPase Rac and Ca2+ to Its N-terminal Extension

  • Hann Ling Wong
  • Reinhard Pinontoan
  • Kana Hasegawa
  • Takashi Yaeno
  • Koh Iba
  • Ryo Tabata
  • Kokoro Hayashi
  • Chojiro Kojima
  • Tsutomu Kawasaki
  • Ko Shimamoto
Conference paper

In this study, using yeast two-hybrid and in vitro binding assays, we found that the CA-OsRac1, but not the dominant negative form, interacted with the N-terminus of OsrbohB. The N-terminus contained two Ca2+-binding EF-hand motifs, was sufficient for OsRac1- OsrbohB interaction. Fluorescence resonance energy transfer microscopy showed that OsRac1 interacted with the N-terminus of OsrbohB predominantly in the GTP-bound form in vivo and the interaction was suppressed by cytosolic Ca2+ ions accumulation. Furthermore, in vitro NADPH oxidase activity assay also showed that GTP-bound OsRac1 enhanced NADPH oxidase activity and the activity was suppressed by Ca2+ ions.

Keywords

Hydrogen Peroxide NADPH Rboh 

Copyright information

© Springer 2007

Authors and Affiliations

  • Hann Ling Wong
    • 1
  • Reinhard Pinontoan
    • 1
  • Kana Hasegawa
    • 1
  • Takashi Yaeno
    • 2
  • Koh Iba
    • 2
  • Ryo Tabata
    • 1
  • Kokoro Hayashi
    • 1
  • Chojiro Kojima
    • 1
  • Tsutomu Kawasaki
    • 1
  • Ko Shimamoto
    • 1
  1. 1.Nara Institute of Science and TechnologyJapan
  2. 2.Department of BiologyKyushu UniversityJapan

Personalised recommendations