Plant Cell Advance Online Publication Published on December 21, 2007; 10.1105/tpc.107.055624
OPEN ACCESS ARTICLE
Received September 9, 2007
Returned for revision November 7, 2007
Accepted December 7, 2007
Regulation of Rice NADPH Oxidase by Binding of Rac GTPase to Its N-Terminal Extension
Hann Ling Wong 1, Reinhard Pinontoan 1, Kokoro Hayashi 2, Ryo Tabata 2, Takashi Yaeno 3, Kana Hasegawa 1, Chojiro Kojima 2, Hirofumi Yoshioka 4, Koh Iba 3, Tsutomu Kawasaki 1, and Ko Shimamoto 1*
1 Laboratory of Plant Molecular Genetics, Nara Institute of Science and Technology, Ikoma, 630-0192 Nara, Japan
2 Laboratory of Biophysics, Graduate School of Biological Sciences, Nara Institute of Science and Technology, Ikoma, 630-0192 Nara, Japan
3 Department of Biology, Faculty of Science, Kyushu University, Hakozaki, Fukuoka 812-8581, Japan
4 Laboratory of Defense in Plant–Pathogen Interactions, Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan
* To whom correspondence should be addressed. E-mail: simamoto{at}bs.naist.jp.
Reactive oxygen species (ROS) produced by NADPH oxidase play critical roles in various cellular activities, including plant innate immunity response. In contrast with the large multiprotein NADPH oxidase complex of phagocytes, in plants, only the homologs of the catalytic subunit gp91phox and the cytosolic regulator small GTPase Rac are found. Plant homologs of the gp91phox subunit are known as Rboh (for respiratory burst oxidase homolog). Although numerous Rboh have been isolated in plants, the regulation of enzymatic activity remains unknown. All rboh genes identified to date possess a conserved N-terminal extension that contains two Ca2+ binding EF-hand motifs. Previously, we ascertained that a small GTPase Rac (Os Rac1) enhanced pathogen-associated molecular pattern–induced ROS production and resistance to pathogens in rice (Oryza sativa). In this study, using yeast two-hybrid assay, we found that interaction between Rac GTPases and the N-terminal extension is ubiquitous and that a substantial part of the N-terminal region of Rboh, including the two EF-hand motifs, is required for the interaction. The direct Rac–Rboh interaction was supported by further studies using in vitro pull-down assay, a nuclear magnetic resonance titration experiment, and in vivo fluorescence resonance energy transfer (FRET) microscopy. The FRET analysis also suggests that cytosolic Ca2+ concentration may regulate Rac–Rboh interaction in a dynamic manner. Furthermore, transient coexpression of Os Rac1 and rbohB enhanced ROS production in Nicotiana benthamiana, suggesting that direct Rac–Rboh interaction may activate NADPH oxidase activity in plants. Taken together, the results suggest that cytosolic Ca2+ concentration may modulate NADPH oxidase activity by regulating the interaction between Rac GTPase and Rboh.
This article has been cited by other articles:

|
 |

|
 |
 
T. Oda, H. Hashimoto, N. Kuwabara, S. Akashi, K. Hayashi, C. Kojima, H. L. Wong, T. Kawasaki, K. Shimamoto, M. Sato, et al.
Structure of the N-terminal Regulatory Domain of a Plant NADPH Oxidase and Its Functional Implications
J. Biol. Chem.,
January 8, 2010;
285(2):
1435 - 1445.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
B. Steffens and M. Sauter
Heterotrimeric G Protein Signaling Is Required for Epidermal Cell Death in Rice
Plant Physiology,
October 1, 2009;
151(2):
732 - 740.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
H. L. Wong and K. Shimamoto
Sending ROS on a Bullet Train
Sci. Signal.,
September 29, 2009;
2(90):
pe60 - pe60.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
G. Miller, K. Schlauch, R. Tam, D. Cortes, M. A. Torres, V. Shulaev, J. L. Dangl, and R. Mittler
The Plant NADPH Oxidase RBOHD Mediates Rapid Systemic Signaling in Response to Diverse Stimuli
Sci. Signal.,
August 18, 2009;
2(84):
ra45 - ra45.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
Y. Zhang, H. Zhu, Q. Zhang, M. Li, M. Yan, R. Wang, L. Wang, R. Welti, W. Zhang, and X. Wang
Phospholipase D{alpha}1 and Phosphatidic Acid Regulate NADPH Oxidase Activity and Production of Reactive Oxygen Species in ABA-Mediated Stomatal Closure in Arabidopsis
PLANT CELL,
August 1, 2009;
21(8):
2357 - 2377.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
F. Lin, H. Ding, J. Wang, H. Zhang, A. Zhang, Y. Zhang, M. Tan, W. Dong, and M. Jiang
Positive feedback regulation of maize NADPH oxidase by mitogen-activated protein kinase cascade in abscisic acid signalling
J. Exp. Bot.,
July 10, 2009;
(2009)
erp157v1.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. Fujiwara, S. Hamada, M. Hiratsuka, Y. Fukao, T. Kawasaki, and K. Shimamoto
Proteome Analysis of Detergent-Resistant Membranes (DRMs) Associated with OsRac1-Mediated Innate Immunity in Rice
Plant Cell Physiol.,
July 1, 2009;
50(7):
1191 - 1200.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
B. Steffens and M. Sauter
Epidermal Cell Death in Rice Is Confined to Cells with a Distinct Molecular Identity and Is Mediated by Ethylene and H2O2 through an Autoamplified Signal Pathway
PLANT CELL,
January 1, 2009;
21(1):
184 - 196.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
J.-Y. Park, J. Jin, Y.-W. Lee, S. Kang, and Y.-H. Lee
Rice Blast Fungus (Magnaporthe oryzae) Infects Arabidopsis via a Mechanism Distinct from That Required for the Infection of Rice
Plant Physiology,
January 1, 2009;
149(1):
474 - 486.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
D. Zhang, D. Wengier, B. Shuai, C.-P. Gui, J. Muschietti, S. McCormick, and W.-H. Tang
The Pollen Receptor Kinase LePRK2 Mediates Growth-Promoting Signals and Positively Regulates Pollen Germination and Tube Growth
Plant Physiology,
November 1, 2008;
148(3):
1368 - 1379.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
A. Nakashima, L. Chen, N. P. Thao, M. Fujiwara, H. L. Wong, M. Kuwano, K. Umemura, K. Shirasu, T. Kawasaki, and K. Shimamoto
RACK1 Functions in Rice Innate Immunity by Interacting with the Rac1 Immune Complex
PLANT CELL,
August 1, 2008;
20(8):
2265 - 2279.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
S. Yalovsky, D. Bloch, N. Sorek, and B. Kost
Regulation of Membrane Trafficking, Cytoskeleton Dynamics, and Cell Polarity by ROP/RAC GTPases
Plant Physiology,
August 1, 2008;
147(4):
1527 - 1543.
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
F. Van Breusegem, J. Bailey-Serres, and R. Mittler
Unraveling the Tapestry of Networks Involving Reactive Oxygen Species in Plants
Plant Physiology,
July 1, 2008;
147(3):
978 - 984.
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
S. Asai, K. Ohta, and H. Yoshioka
MAPK Signaling Regulates Nitric Oxide and NADPH Oxidase-Dependent Oxidative Bursts in Nicotiana benthamiana
PLANT CELL,
May 1, 2008;
20(5):
1390 - 1406.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
N. P. Thao, L. Chen, A. Nakashima, S.-i. Hara, K. Umemura, A. Takahashi, K. Shirasu, T. Kawasaki, and K. Shimamoto
RAR1 and HSP90 Form a Complex with Rac/Rop GTPase and Function in Innate-Immune Responses in Rice
PLANT CELL,
December 1, 2007;
19(12):
4035 - 4045.
[Abstract]
[Full Text]
[PDF]
|
 |
|
|
|