The vast majority of agricultural land undergoes abiotic stress that can significantly reduce agricultural yields. Understanding the mechanisms of plant defenses against stresses and putting this knowledge into practice is, therefore, an integral part of sustainable agriculture. In this review, we focus on current findings in plant resistance to four cardinal abiotic stressors-drought, heat, salinity, and low temperatures. Apart from the description of the newly discovered mechanisms of signaling and resistance to abiotic stress, this review also focuses on the importance of primary and secondary metabolites, including carbohydrates, amino acids, phenolics, and phytohormones. A meta-analysis of transcriptomic studies concerning the model plant Arabidopsis demonstrates the long-observed phenomenon that abiotic stressors induce different signals and effects at the level of gene expression, but genes whose regulation is similar under most stressors can still be traced. The analysis further reveals the transcriptional modulation of Golgi-targeted proteins in response to heat stress. Our analysis also highlights several genes that are similarly regulated under all stress conditions. These genes support the central role of phytohormones in the abiotic stress response, and the importance of some of these in plant resistance has not yet been studied. Finally, this review provides information about the response to abiotic stress in major European crop plants-wheat, sugar beet, maize, potatoes, barley, sunflowers, grapes, rapeseed, tomatoes, and apples.
Phytophthora cinnamomi Rands is a cosmopolite pathogen of woody plants which during the last couple of centuries has spread all over the world from its center of origin in Southeast Asia. In contrast to Chinese cork oak (Quercus variabilis Blume) forests native to Asia, which are generally healthy despite the presence of the pathogen, the populations of Cork oaks (Quercus suber L.) in Europe have been severely decimated by P. cinnamomi. The present study aims at identifying the differences in the early proteomic and metabolomic response of these two tree species that lead to their differences in susceptibility to P. cinnamomi. By using micropropagated clonal plants, we tried to minimize the plant-to-plant differences in the defense response that is maximized by the high intraspecific genetic variability inherent to the Quercus genus. The evolution on the content of Phytophthora proteins in the roots during the first 36 h after inoculation suggests a slower infection process in Q. variabilis plants. These plants displayed a significant decrease in sugars in the roots, together with a downregulation of proteins related to carbon metabolism. In the leaves, the biggest changes in proteomic profiling were observed 16 h after inoculation, and included increased abundance of peroxidases, superoxide dismutases and glutathione S-transferases in Q. variabilis plants, which probably contributed to decrease its susceptibility to P. cinnamomi.
- Publikační typ
- časopisecké články MeSH
Plant survival in temperate zones requires efficient cold acclimation, which is strongly affected by light and temperature signal crosstalk, which converge in modulation of hormonal responses. Cold under low light conditions affected Arabidopsis responses predominantly in apices, possibly because energy supplies were too limited for requirements of these meristematic tissues, despite a relatively high steady-state quantum yield. Comparing cold responses at optimal light intensity and low light, we found activation of similar defence mechanisms-apart from CBF1-3 and CRF3-4 pathways, also transient stimulation of cytokinin type-A response regulators, accompanied by fast transient increase of trans-zeatin in roots. Upregulated expression of components of strigolactone (and karrikin) signalling pathway indicated involvement of these phytohormones in cold responses. Impaired response of phyA, phyB, cry1 and cry2 mutants reflected participation of these photoreceptors in acquiring freezing tolerance (especially cryptochrome CRY1 at optimal light intensity and phytochrome PHYA at low light). Efficient cold acclimation at optimal light was associated with upregulation of trans-zeatin in leaves and roots, while at low light, cytokinin (except cis-zeatin) content remained diminished. Cold stresses induced elevation of jasmonic acid and salicylic acid (in roots). Low light at optimal conditions resulted in strong suppression of cytokinins, jasmonic and salicylic acid.
Phytophthora is arguably one of the most damaging genera of plant pathogens. This pathogen is well suited to transmission via the international plant trade, and globalization has been promoting its spread since the 19th century. Early detection is essential for reducing its economic and ecological impact. Here, a shotgun proteomics approach was utilized for Phytophthora analysis. The collection of 37 Phytophthora isolates representing 12 different species was screened for species-specific peptide patterns. Next, Phytophthora proteins were detected in planta, employing model plants Solanum tuberosum and Hordeum vulgare. Although the evolutionarily conserved sequences represented more than 10% of the host proteome and limited the pathogen detection, the comparison between qPCR and protein data highlighted more than 300 protein markers, which correlated positively with the amount of P. infestans DNA. Finally, the analysis of P. palmivora response in barley revealed significant alterations in plant metabolism. These changes included enzymes of cell wall metabolism, ROS production, and proteins involved in trafficking. The observed root-specific attenuation in stress-response mechanisms, including the biosynthesis of jasmonates, ethylene and polyamines, and an accumulation of serotonin, provided the first insight into molecular mechanisms behind this particular biotic interaction.
- MeSH
- chromatografie kapalinová MeSH
- fyziologický stres MeSH
- hmotnostní spektrometrie MeSH
- ječmen (rod) enzymologie metabolismus mikrobiologie MeSH
- listy rostlin metabolismus mikrobiologie MeSH
- metabolické sítě a dráhy MeSH
- nemoci rostlin mikrobiologie MeSH
- peptidy metabolismus MeSH
- Phytophthora infestans genetika izolace a purifikace MeSH
- polymerázová řetězová reakce MeSH
- proteom metabolismus MeSH
- proteomika MeSH
- reaktivní formy kyslíku metabolismus MeSH
- rostlinné proteiny metabolismus MeSH
- Solanum tuberosum metabolismus mikrobiologie MeSH
- Publikační typ
- časopisecké články MeSH
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
DELLA transcriptional regulators are central components in the control of plant growth responses to the environment. This control is considered to be mediated by changes in the metabolism of the hormones gibberellins (GAs), which promote the degradation of DELLAs. However, here we show that warm temperature or shade reduced the stability of a GA-insensitive DELLA allele in Arabidopsis thaliana Furthermore, the degradation of DELLA induced by the warmth preceded changes in GA levels and depended on the E3 ubiquitin ligase CONSTITUTIVELY PHOTOMORPHOGENIC1 (COP1). COP1 enhanced the degradation of normal and GA-insensitive DELLA alleles when coexpressed in Nicotiana benthamiana. DELLA proteins physically interacted with COP1 in yeast, mammalian, and plant cells. This interaction was enhanced by the COP1 complex partner SUPRESSOR OF phyA-105 1 (SPA1). The level of ubiquitination of DELLA was enhanced by COP1 and COP1 ubiquitinated DELLA proteins in vitro. We propose that DELLAs are destabilized not only by the canonical GA-dependent pathway but also by COP1 and that this control is relevant for growth responses to shade and warm temperature.
- MeSH
- Arabidopsis chemie enzymologie genetika metabolismus MeSH
- gibereliny metabolismus MeSH
- proteiny huseníčku genetika metabolismus MeSH
- proteolýza MeSH
- regulace genové exprese u rostlin MeSH
- regulátory růstu rostlin metabolismus MeSH
- represorové proteiny genetika metabolismus MeSH
- stabilita proteinů MeSH
- ubikvitinace MeSH
- ubikvitinligasy genetika metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
Cytokinin is an indispensable phytohormone responsible for physiological processes ranging from root development to leaf senescence. The term "cytokinin" refers to several dozen adenine-derived compounds occurring naturally in plants. Cytokinins (CKs) can be divided into various classes and forms; base forms are generally considered to be active while highly abundant cytokinin-N-glucosides (CKNGs), composed of a CK base irreversibly conjugated to a glucose molecule, are considered inactive. However, results from early CK studies suggest CKNGs do not always lack activity despite the perpetuation over several decades in the literature that they are inactive. Here we show that exogenous application of trans-Zeatin-N-glucosides (tZNGs, a specific class of CKNGs) to Arabidopsis results in CK response comparable to the application of an active CK base. These results are most apparent in senescence assays where both a CK base (tZ) and tZNGs (tZ7G, tZ9G) delay senescence in cotyledons. Further experiments involving root growth and shoot regeneration revealed tZNGs do not always have the same effects as tZ, and have largely distinct effects on the transcriptome and proteome. These data are in contrast to previous reports of CKNGs being inactive and raise questions about the function of these compounds as well as their mechanism of action.
De-etiolation is the first developmental process under light control allowing the heterotrophic seedling to become autotrophic. The phytohormones cytokinins (CKs) largely contribute to this process. Reversible phosphorylation is a key event of cell signaling, allowing proteins to become active or generating a binding site for specific protein interaction. 14-3-3 proteins regulate a variety of plant responses. The expression, hormonal regulation, and proteomic network under the control of 14-3-3s were addressed in tomato (Solanum lycopersicum L.) during blue light-induced photomorphogenesis. Two isoforms were specifically investigated due to their high expression during tomato de-etiolation. The multidisciplinary approach demonstrated that TFT9 expression, but not TFT6, was regulated by CKs and identified cis-regulating elements required for this response. Our study revealed >130 potential TFT6/9 interactors. Their functional annotation predicted that TFTs might regulate the activity of proteins involved notably in cell wall strengthening or primary metabolism. Several potential interactors were also predicted to be CK-responsive. For the first time, the 14-3-3 interactome linked to de-etiolation was investigated and evidenced that 14-3-3s might be involved in CK signaling pathway, cell expansion inhibition and steady-state growth rate establishment, and reprograming from heterotrophy to autotrophy. BIOLOGICAL SIGNIFICANCE: Tomato (Solanum lycopersicum L.) is one of the most important vegetables consumed all around the world and represents probably the most preferred garden crop. Regulation of hypocotyl growth by light plays an important role in the early development of a seedling, and consequently the homogeneity of the culture. The present study focuses on the importance of tomato 14-3-3/TFT proteins in this process. We provide here the first report of 14-3-3 interactome in the regulation of light-induced de-etiolation and subsequent photomorphogenesis. Our data provide new insights into light-induced de-etiolation and open new horizons for dissecting the post-transcriptional regulations.
- MeSH
- chromatografie afinitní MeSH
- mapy interakcí proteinů * MeSH
- proteiny 14-3-3 metabolismus MeSH
- proteomika * MeSH
- rostlinné proteiny metabolismus MeSH
- semenáček růst a vývoj MeSH
- Solanum lycopersicum růst a vývoj MeSH
- světlo * MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Hydrogen peroxide promotes seed germination, but the molecular mechanisms underlying this process are unclear. This study presents the results of eggplant (Solanum melongena) germination analyses conducted at two different temperatures and follows the effect of hydrogen peroxide treatment on seed germination and the seed proteome. Hydrogen peroxide was found to promote eggplant germination in a way not dissimilar to that of increased temperature stimuli. LC-MS profiling detected 729 protein families, 77 of which responded to a temperature increase or hydrogen peroxide treatment. These differentially abundant proteins were found to be involved in a number of processes, including protein and amino acid metabolism, carbohydrate metabolism, and the glyoxylate cycle. There was a very low overlap between hydrogen peroxide and temperature-responsive proteins, highlighting the differences behind the seemingly similar outcomes. Furthermore, the observed changes from the seed proteome indicate that hydrogen peroxide treatment diminished the seed endogenous hydrogen peroxide pool and that a part of manifested positive hydrogen peroxide effect might be related to altered sensitivity to abscisic acid.
- MeSH
- chromatografie kapalinová MeSH
- fyziologický stres účinky léků MeSH
- hmotnostní spektrometrie MeSH
- klíčení účinky léků MeSH
- metabolismus sacharidů účinky léků MeSH
- peroxid vodíku farmakologie MeSH
- regulace genové exprese u rostlin účinky léků MeSH
- rostlinné proteiny metabolismus MeSH
- Solanum melongena účinky léků fyziologie MeSH
- teplota MeSH
- vývojová regulace genové exprese účinky léků MeSH
- Publikační typ
- časopisecké články MeSH
The phytohormone cytokinin has been shown to affect many aspects of plant development ranging from the regulation of the shoot apical meristem to leaf senescence. However, some studies have reported contradictory effects of cytokinin on leaf physiology. Therefore cytokinin treatments cause both chlorosis and increased greening and both lead to decrease or increase in cell size. To elucidate this multifaceted role of cytokinin in leaf development, we have employed a system of temporal controls over the cytokinin pool and investigated the consequences of modulated cytokinin levels in the third leaf of Arabidopsis. We show that, at the cell proliferation phase, cytokinin is needed to maintain cell proliferation by blocking the transition to cell expansion and the onset of photosynthesis. Transcriptome profiling revealed regulation by cytokinin of a gene suite previously shown to affect cell proliferation and expansion and thereby a molecular mechanism by which cytokinin modulates a molecular network underlying the cellular responses. During the cell expansion phase, cytokinin stimulates cell expansion and differentiation. Consequently, a cytokinin excess at the cell expansion phase results in an increased leaf and rosette size fueled by higher cell expansion rate, yielding higher shoot biomass. Proteome profiling revealed the stimulation of primary metabolism by cytokinin, in line with an increased sugar content that is expected to increase turgor pressure, representing the driving force of cell expansion. Therefore, the developmental timing of cytokinin content fluctuations, together with a tight control of primary metabolism, is a key factor mediating transitions from cell proliferation to cell expansion in leaves.
- MeSH
- Arabidopsis genetika růst a vývoj fyziologie MeSH
- cytokininy metabolismus MeSH
- genová ontologie MeSH
- listy rostlin genetika růst a vývoj fyziologie MeSH
- proliferace buněk MeSH
- proteom * MeSH
- regulátory růstu rostlin metabolismus MeSH
- signální transdukce * MeSH
- transkriptom * MeSH
- zvětšování buněk MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
