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Arabidopsis gp91phox homologues AtrbohD and AtrbohF are required for accumulation of reactive oxygen intermediates in the plant defense response. Proceedings of the National Academy of Sciences of the United States of America, 99, 517-522

Department of Biology and Curriculum in Genetics and Molecular Biology, CB 3280, 108 Coker Hall, University of North Carolina, Chapel Hill, NC 27599-3280, USA.
Proceedings of the National Academy of Sciences (Impact Factor: 9.81). 02/2002; 99(1):517-22. DOI: 10.1073/pnas.012452499
Source: PubMed

ABSTRACT Reactive oxygen intermediates (ROI) are strongly associated with plant defense responses. The origin of these ROI has been controversial. Arabidopsis respiratory burst oxidase homologues (rboh genes) have been proposed to play a role in ROI generation. We analyzed lines carrying dSpm insertions in the highly expressed AtrbohD and AtrbohF genes. Both are required for full ROI production observed during incompatible interactions with the bacterial pathogen Pseudomonas syringae pv. tomato DC3000(avrRpm1) and the oomycete parasite Peronospora parasitica. We also observed reduced cell death, visualized by trypan blue stain and reduced electrolyte leakage, in the Atrboh mutants after DC3000(avrRpm1) inoculation. However, enhanced cell death is observed after infection of mutant lines with P. parasitica. Paradoxically, although atrbohD mutation eliminated the majority of total ROI production, atrbohF mutation exhibited the strongest effect on cell death.

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    • "In contrast with the phenotypes observed in N. benthamiana, abolishment of H 2 O 2 production in rbohD plants reduced, rather than increased, sporangiophore development and fungal biomass upon inoculation with Peronospora parasitica (Torres et al., 2002) and Alternaria brassicicola (Pogá ny et al., 2009), respectively. The latter work also showed that the rbohD mutant is not affected in stress-related responses (Pogá ny et al., 2009) and indicates that RBOHD actually suppresses cell death (Torres et al., 2002; Pogá ny et al., 2009). "
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    • "Implication of ROS in the ABA signaling pathways leading to stomatal closure was confirmed by the identification of mutants of NADPH oxidases. These are plasma membrane enzymes responsible for ROS generation (Torres et al. 2002, Kwak et al. 2003). In the Arabidopsis NADPH oxidase double mutant atrbohD/F, ROS generation and stomatal closure normally observed upon ABA treatment are both reduced, confirming the importance of ROS in ABA effects (Kwak et al. 2003). "
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    • "pathogen-associated molecular patterns, PAMPs) by membraneassociated receptors allows plants to mount a defence response leading to PAMP-triggered immunity (PTI) (Monaghan and Zipfel, 2012). Early signalling events, including the production of reactive oxygen species (ROS) (Torres et al., 2002), Ca 2+ signalling (Cheval et al., 2013) and mitogen-activated protein (MAP) kinase activation (Rasmussen et al., 2012), trigger profound transcriptomic reprogramming. The synthesis of diverse antimicrobial metabolites , callose deposition, cell wall strengthening and the production of pathogenesis-related (PR) proteins are components of the defence response (Eulgem, 2005) underlying PTI, and are sufficient to protect plants against a broad range of potentially harmful microbes. "
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