Molecular Crosstalk Between PAMP-Triggered Immunity and Photosynthesis

Heinrich-Heine University, Dusseldorf, Germany.
Molecular Plant-Microbe Interactions (Impact Factor: 3.94). 05/2012; 25(8):1083-92. DOI: 10.1094/MPMI-11-11-0301
Source: PubMed


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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    • "ulases , and proteases ) producing maceration of the infected tissue by breaking down plant cell walls , as reviewed by Toth et al . ( 2003 ) . Many authors have addressed the effect of biotrophs and hemi - biotrophs on plant physiology . However , photosynthetic responses in plants to necrotrophs have been paid little attention . A recent study ( Göhre et al . , 2012 ) demonstrated how PAMPs triggered immunity response , which influences photosynthesis and their crosstalk via the NPQ on Arabidopsis plants treated with the PAMP flg22 , a peptide derived from flagellin . NPQ is a defense mechanism related to photosynthesis that protects the thylakoid membrane of the chloroplast from excess excitation "
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