Phytophthora cinnamomi is one of the most invasive tree pathogens that devastates wild and cultivated forests. Due to its wide host range, knowledge of the infection process at the molecular level is lacking for most of its tree hosts. To expand the repertoire of studied Phytophthora-woody plant interactions and identify molecular mechanisms that can facilitate discovery of novel ways to control its spread and damaging effects, we focused on the interaction between P. cinnamomi and sweet chestnut (Castanea sativa), an economically important tree for the wood processing industry. By using a combination of proteomics, metabolomics, and targeted hormonal analysis, we mapped the effects of P. cinnamomi attack on stem tissues immediately bordering the infection site and away from it. P. cinnamomi led to a massive reprogramming of the chestnut proteome and accumulation of the stress-related hormones salicylic acid (SA) and jasmonic acid (JA), indicating that stem inoculation can be used as an easily accessible model system to identify novel molecular players in P. cinnamomi pathogenicity.
- MeSH
- cyklopentany metabolismus MeSH
- dřevo MeSH
- Fagaceae metabolismus mikrobiologie MeSH
- homeostáza MeSH
- kořeny rostlin MeSH
- kyselina salicylová metabolismus MeSH
- metabolomika MeSH
- nemoci rostlin mikrobiologie MeSH
- oxylipiny metabolismus MeSH
- Phytophthora patogenita MeSH
- proteomika MeSH
- regulátory růstu rostlin metabolismus MeSH
- signální transdukce MeSH
- vazebná místa MeSH
- výpočetní biologie MeSH
- Publikační typ
- časopisecké články MeSH
Alterations of hydrogen peroxide (H2O2) levels have a profound impact on numerous signaling cascades orchestrating plant growth, development, and stress signaling, including programmed cell death. To expand the repertoire of known molecular mechanisms implicated in H2O2 signaling, we performed a forward chemical screen to identify small molecules that could alleviate the photorespiratory-induced cell death phenotype of Arabidopsisthaliana mutants lacking H2O2-scavenging capacity by peroxisomal catalase2. Here, we report the characterization of pakerine, an m-sulfamoyl benzamide from the sulfonamide family. Pakerine alleviates the cell death phenotype of cat2 mutants exposed to photorespiration-promoting conditions and delays dark-induced senescence in wild-type Arabidopsis leaves. By using a combination of transcriptomics, metabolomics, and affinity purification, we identified abnormal inflorescence meristem 1 (AIM1) as a putative protein target of pakerine. AIM1 is a 3-hydroxyacyl-CoA dehydrogenase involved in fatty acid β-oxidation that contributes to jasmonic acid (JA) and salicylic acid (SA) biosynthesis. Whereas intact JA biosynthesis was not required for pakerine bioactivity, our results point toward a role for β-oxidation-dependent SA production in the execution of H2O2-mediated cell death.
- MeSH
- Arabidopsis cytologie účinky léků genetika metabolismus MeSH
- buněčná smrt účinky léků MeSH
- buněčné dýchání účinky léků genetika MeSH
- cyklopentany metabolismus MeSH
- fotosyntéza účinky léků genetika MeSH
- fyziologický stres MeSH
- hydroponie metody MeSH
- kyselina salicylová metabolismus MeSH
- listy rostlin cytologie účinky léků metabolismus MeSH
- meristém cytologie účinky léků metabolismus MeSH
- multienzymové komplexy genetika metabolismus MeSH
- oxylipiny metabolismus MeSH
- peroxid vodíku antagonisté a inhibitory farmakologie MeSH
- proteiny huseníčku genetika metabolismus MeSH
- regulace genové exprese u rostlin * MeSH
- rostlinné buňky účinky léků metabolismus MeSH
- semena rostlinná účinky léků MeSH
- signální transdukce MeSH
- stanovení celkové genové exprese MeSH
- sulfonamidy chemická syntéza farmakologie MeSH
- transkriptom MeSH
- výpočetní biologie metody MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Although structurally simple, viroids can trigger numerous changes in host plants and cause loss of yield in agronomically important crops. This study investigated changes in the endogenous status of phytohormones and antioxidant enzyme activity in Solanum tuberosum cv. Désirée in response to Potato spindle tuber viroid (PSTVd) infection. Phytohormone analysis showed that the content of endogenous jasmonic acid (JA) and its precursor cis-OPDA significantly increased in leaves, while the content of castasterone (CS) increased in both leaves and tubers of systemically infected plants compared to mock-inoculated control plants at 8 weeks post-inoculation. The indole-3-acetic acid content moderately increased only in tubers, while no differences in salicylic acid and abscisic acid content were observed between infected and control plants. Changes in endogenous phytohormone content were associated with upregulated expression of genes involved in the biosynthesis of JA and brassinosteroids, and the metabolism of auxins. Additionally, PSTVd infection provoked overproduction of hydrogen peroxide, which coincided with increased activity of guaiacol peroxidase in leaves and ascorbate peroxidase in potato tubers. The activity of catalase decreased in leaves, while superoxide dismutase activity remained steady regardless of the treatment and organ type. Total ascorbate and glutathione did not change significantly, although a shift towards oxidized forms was observed. Results suggest the existence of organ-specific differences in phytohormone and antioxidative responses in potato upon PSTVd infection. Possible effects of the observed changes on symptom development are discussed.
- MeSH
- antioxidancia metabolismus MeSH
- brassinosteroidy metabolismus MeSH
- chlorofyl metabolismus MeSH
- cholestanoly metabolismus MeSH
- cyklopentany metabolismus MeSH
- hlízy rostlin metabolismus MeSH
- kyseliny indoloctové metabolismus MeSH
- listy rostlin metabolismus MeSH
- nemoci rostlin virologie MeSH
- oxylipiny metabolismus MeSH
- regulátory růstu rostlin metabolismus MeSH
- Solanum tuberosum metabolismus fyziologie virologie MeSH
- viroidy metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
MAIN CONCLUSION: The level of resistance induced in different tomato genotypes after β-CRY treatment correlated with the upregulation of defence genes, but not sterol binding and involved ethylene and jasmonic acid signalling. Elicitins, a family of small proteins secreted by Phytophthora and Pythium spp., are the most well-known microbe-associated molecular patterns of oomycetes, a lineage of fungus-like organisms that include many economically significant crop pathogens. The responses of tomato plants to elicitin INF1 produced by Phytophthora infestans have been studied extensively. Here, we present studies on the responses of three tomato genotypes to β-cryptogein (β-CRY), a potent elicitin secreted by Phytophthora cryptogea that induces hypersensitive response (HR) cell death in tobacco plants and confers greater resistance to oomycete infection than acidic elicitins like INF1. We also studied β-CRY mutants impaired in sterol binding (Val84Phe) and interaction with the binding site on tobacco plasma membrane (Leu41Phe), because sterol binding was suggested to be important in INF1-induced resistance. Treatment with β-CRY or the Val84Phe mutant induced resistance to powdery mildew caused by the pathogen Pseudoidium neolycopersici, but not the HR cell death observed in tobacco and potato plants. The level of resistance induced in different tomato genotypes correlated with the upregulation of defence genes including defensins, β-1,3-glucanases, heveins, chitinases, osmotins, and PR1 proteins. Treatment with the Leu41Phe mutant did not induce this upregulation, suggesting similar elicitin recognition in tomato and tobacco. However, here β-CRY activated ethylene and jasmonic acid signalling, but not salicylic acid signalling, demonstrating that elicitins activate different downstream signalling processes in different plant species. This could potentially be exploited to enhance the resistance of Phytophthora-susceptible crops.
- MeSH
- cyklopentany metabolismus MeSH
- ethyleny metabolismus MeSH
- fungální proteiny metabolismus MeSH
- interakce hostitele a patogenu MeSH
- kyselina salicylová metabolismus MeSH
- listy rostlin metabolismus mikrobiologie MeSH
- nemoci rostlin mikrobiologie MeSH
- oxylipiny metabolismus MeSH
- peroxid vodíku metabolismus MeSH
- Phytophthora MeSH
- Pythium MeSH
- reaktivní formy kyslíku metabolismus MeSH
- regulátory růstu rostlin metabolismus MeSH
- signální transdukce * MeSH
- Solanum lycopersicum metabolismus mikrobiologie fyziologie MeSH
- Publikační typ
- časopisecké články MeSH
Plant phospholipase Ds (PLDs), essential regulators of phospholipid signaling, function in multiple signal transduction cascades; however, the mechanisms regulating PLDs in response to pathogens remain unclear. Here, we found that Arabidopsis (Arabidopsis thaliana) PLDδ accumulated in cells at the entry sites of the barley powdery mildew fungus, Blumeria graminis f. sp hordei Using fluorescence recovery after photobleaching and single-molecule analysis, we observed higher PLDδ density in the plasma membrane after chitin treatment; PLDδ also underwent rapid exocytosis. Fluorescence resonance energy transfer with fluorescence lifetime imaging microscopy showed that the interaction between PLDδ and the microdomain marker AtREMORIN1.3 (AtREM1.3) increased in response to chitin, indicating that exocytosis facilitates rapid, efficient sorting of PLDδ into microdomains upon pathogen stimulus. We further unveiled a trade-off between brefeldin A (BFA)-resistant and -sensitive pathways in secretion of PLDδ under diverse conditions. Upon pathogen attack, PLDδ secretion involved syntaxin-associated VAMP721/722-mediated exocytosis sensitive to BFA. Analysis of phosphatidic acid (PA), hydrogen peroxide, and jasmonic acid (JA) levels and expression of related genes indicated that the relocalization of PLDδ is crucial for its activation to produce PA and initiate reactive oxygen species and JA signaling pathways. Together, our findings revealed that the translocation of PLDδ to papillae is modulated by exocytosis, thus triggering PA-mediated signaling in plant innate immunity.plantcell;31/12/3015/FX1F1fx1.
- MeSH
- Arabidopsis genetika imunologie metabolismus mikrobiologie MeSH
- Ascomycota patogenita MeSH
- brefeldin A imunologie metabolismus MeSH
- buněčná membrána metabolismus MeSH
- chitin imunologie metabolismus MeSH
- cyklopentany metabolismus MeSH
- exocytóza účinky léků imunologie MeSH
- fosfolipasa D genetika metabolismus MeSH
- kyseliny fosfatidové metabolismus MeSH
- nemoci rostlin imunologie mikrobiologie MeSH
- oxylipiny metabolismus MeSH
- peroxid vodíku metabolismus MeSH
- přirozená imunita * účinky léků MeSH
- proteiny huseníčku metabolismus MeSH
- proteiny Qa-SNARE metabolismus MeSH
- proteiny R-SNARE metabolismus MeSH
- proteiny SNARE genetika metabolismus MeSH
- reaktivní formy kyslíku metabolismus MeSH
- signální transdukce imunologie fyziologie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Jasmonates (JAs) are signals in plant stress responses and development. One of the first observed and prominent responses to JAs is the induction of biosynthesis of different groups of secondary compounds. Among them are nicotine, isoquinolines, glucosinolates, anthocyanins, benzophenanthridine alkaloids, artemisinin, and terpenoid indole alkaloids (TIAs), such as vinblastine. This brief review describes modes of action of JAs in the biosynthesis of anthocyanins, nicotine, TIAs, glucosinolates and artemisinin. After introducing JA biosynthesis, the central role of the SCFCOI1-JAZ co-receptor complex in JA perception and MYB-type and MYC-type transcription factors is described. Brief comments are provided on primary metabolites as precursors of secondary compounds. Pathways for the biosynthesis of anthocyanin, nicotine, TIAs, glucosinolates and artemisinin are described with an emphasis on JA-dependent transcription factors, which activate or repress the expression of essential genes encoding enzymes in the biosynthesis of these secondary compounds. Applied aspects are discussed using the biotechnological formation of artemisinin as an example of JA-induced biosynthesis of secondary compounds in plant cell factories.
- MeSH
- anthokyaniny biosyntéza MeSH
- artemisininy metabolismus MeSH
- biologické modely MeSH
- biosyntetické dráhy MeSH
- cyklopentany metabolismus MeSH
- glukosinoláty biosyntéza MeSH
- metabolické inženýrství MeSH
- nikotin biosyntéza MeSH
- oxylipiny metabolismus MeSH
- regulátory růstu rostlin biosyntéza metabolismus MeSH
- rostlinné proteiny metabolismus MeSH
- rostliny genetika metabolismus MeSH
- sekologanin-tryptaminové alkaloidy metabolismus MeSH
- signální transdukce MeSH
- transkripční faktory metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
The plant cell wall plays an important role in damage-associated molecular pattern-induced resistance to pathogens and herbivorous insects. Our current understanding of cell wall-mediated resistance is largely based on the degree of pectin methylesterification. However, little is known about the role of pectin acetylesterification in plant immunity. This study describes how one pectin-modifying enzyme, PECTIN ACETYLESTERASE 9 (PAE9), affects the Arabidopsis (Arabidopsis thaliana) transcriptome, secondary metabolome, and aphid performance. Electro-penetration graphs showed that Myzus persicae aphids established phloem feeding earlier on pae9 mutants. Whole-genome transcriptome analysis revealed a set of 56 differentially expressed genes (DEGs) between uninfested pae9-2 mutants and wild-type plants. The majority of the DEGs were enriched for biotic stress responses and down-regulated in the pae9-2 mutant, including PAD3 and IGMT2, involved in camalexin and indole glucosinolate biosynthesis, respectively. Relative quantification of more than 100 secondary metabolites revealed decreased levels of several compounds, including camalexin and oxylipins, in two independent pae9 mutants. In addition, absolute quantification of phytohormones showed that jasmonic acid (JA), jasmonoyl-Ile, salicylic acid, abscisic acid, and indole-3-acetic acid were compromised due to PAE9 loss of function. After aphid infestation, however, pae9 mutants increased their levels of camalexin, glucosinolates, and JA, and no long-term effects were observed on aphid fitness. Overall, these data show that PAE9 is required for constitutive up-regulation of defense-related compounds, but that it is not required for aphid-induced defenses. The signatures of phenolic antioxidants, phytoprostanes, and oxidative stress-related transcripts indicate that the processes underlying PAE9 activity involve oxidation-reduction reactions.
- MeSH
- acetylesterasa metabolismus MeSH
- Arabidopsis genetika metabolismus parazitologie MeSH
- býložravci fyziologie MeSH
- down regulace genetika MeSH
- genové regulační sítě MeSH
- glukosinoláty metabolismus MeSH
- indoly metabolismus MeSH
- metabolom genetika MeSH
- mšice fyziologie MeSH
- mutace genetika MeSH
- oxidační stres MeSH
- oxylipiny metabolismus MeSH
- proteiny huseníčku metabolismus MeSH
- regulace genové exprese u rostlin MeSH
- regulační geny MeSH
- regulátory růstu rostlin metabolismus MeSH
- sekundární metabolismus MeSH
- thiazoly metabolismus MeSH
- transkripční faktory metabolismus MeSH
- transkriptom genetika MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Adventitious rooting is a post-embryonic developmental program governed by a multitude of endogenous and environmental cues. Auxin, along with other phytohormones, integrates and translates these cues into precise molecular signatures to provide a coherent developmental output. Auxin signaling guides every step of adventitious root (AR) development from the early event of cell reprogramming and identity transitions until emergence. We have previously shown that auxin signaling controls the early events of AR initiation (ARI) by modulating the homeostasis of the negative regulator jasmonate (JA). Although considerable knowledge has been acquired about the role of auxin and JA in ARI, the genetic components acting downstream of JA signaling and the mechanistic basis controlling the interaction between these two hormones are not well understood. Here we provide evidence that COI1-dependent JA signaling controls the expression of DAO1 and its closely related paralog DAO2. In addition, we show that the dao1-1 loss of function mutant produces more ARs than the wild type, probably due to its deficiency in accumulating JA and its bioactive metabolite JA-Ile. Together, our data indicate that DAO1 controls a sensitive feedback circuit that stabilizes the auxin and JA crosstalk during ARI.
- MeSH
- Arabidopsis genetika metabolismus MeSH
- cyklopentany metabolismus MeSH
- kořeny rostlin genetika růst a vývoj MeSH
- kyseliny indoloctové metabolismus MeSH
- oxidoreduktasy genetika metabolismus MeSH
- oxylipiny metabolismus MeSH
- proteiny huseníčku genetika metabolismus MeSH
- signální transdukce MeSH
- Publikační typ
- časopisecké články MeSH
