Article

Molecular crosstalk between PAMP-triggered immunity and photosynthesis. Mol Plant Microbe Interact

Heinrich-Heine University, Dusseldorf, Germany.
Molecular Plant-Microbe Interactions (Impact Factor: 4.46). 05/2012; 25(8):1083-92. DOI: 10.1094/MPMI-11-11-0301
Source: PubMed

ABSTRACT The innate immune system allows plants to respond to potential pathogens in an appropriate manner while minimizing damage and energy costs. Photosynthesis provides a sustained energy supply and, therefore, has to be integrated into the defense against pathogens. Although changes in photosynthetic activity during infection have been described, a detailed and conclusive characterization is lacking. Here, we addressed whether activation of early defense responses by pathogen-associated molecular patterns (PAMPs) triggers changes in photosynthesis. Using proteomics and chlorophyll fluorescence measurements, we show that activation of defense by PAMPs leads to a rapid decrease in nonphotochemical quenching (NPQ). Conversely, NPQ also influences several responses of PAMP-triggered immunity. In a mutant impaired in NPQ, apoplastic reactive oxygen species production is enhanced and defense gene expression is differentially affected. Although induction of the early defense markers WRKY22 and WRKY29 is enhanced, induction of the late markers PR1 and PR5 is completely abolished. We propose that regulation of NPQ is an intrinsic component of the plant's defense program.

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    • "This can be explained by different photoinhibition of PSII rates, which increased the levels of transcript genes involved in electron transport chain of photosystems (Cramer et al., 2007). The balance between light capture and energy use may be of great relevance for drought tolerance and possibly for immune response (Göhre et al., 2012). Tolerant genotype also exhibited a low enhanced expression of NCED2 involved in ABA biosynthesis. "
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    Journal of Experimental Botany 11/2014; 66(3). DOI:10.1093/jxb/eru436 · 5.79 Impact Factor
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    • "Genes encoding photosynthesis components were repressed by Xoo infection in rice (Narsai et al. 2013). Activation of defense by PAMPs leads to rapid decrease in nonphotochemical quenching (Gohre et al. 2012). Our data showed genes encoding proteins involved in light reactions, Calvin cycle and ATP synthesis were repressed in rice after treatment with WT Xoo relative to the mutant (Figure 4 and Additional file 4: Table S4 "
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    • "[41]). In addition, a causal link between NPQ capacity and pathogen resistance has been recently suggested [42]. Thus, at the start of this study we hypothesized that there could be intriguing evolutionary trade-offs between photoprotection and biotic stress resistance. "
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