While endophytic fungi offer promising avenues for bolstering plant resilience against abiotic stressors, the molecular mechanisms behind this biofortification remain largely unknown. This study employed a multifaceted approach, combining plant physiology, proteomic, metabolomic, and targeted hormonal analyses to illuminate the early response of Brassica napus to Acremonium alternatum during the nascent stages of their interaction. Notably, under optimal growth conditions, the initial reaction to fungus was relatively subtle, with no visible alterations in plant phenotype and only minor impacts on the proteome and metabolome. Interestingly, the identified proteins associated with the Acremonium response included TUDOR 1, Annexin D4, and a plastidic K+ efflux antiporter, hinting at potential processes that could counter abiotic stressors, particularly salt stress. Subsequent experiments validated this hypothesis, showcasing significantly enhanced growth in Acremonium-inoculated plants under salt stress. Molecular analyses revealed a profound impact on the plant's proteome, with over 50% of salt stress response proteins remaining unaffected in inoculated plants. Acremonium modulated ribosomal proteins, increased abundance of photosynthetic proteins, enhanced ROS metabolism, accumulation of V-ATPase, altered abundances of various metabolic enzymes, and possibly promoted abscisic acid signaling. Subsequent analyses validated the accumulation of this hormone and its enhanced signaling. Collectively, these findings indicate that Acremonium promotes salt tolerance by orchestrating abscisic acid signaling, priming the plant's antioxidant system, as evidenced by the accumulation of ROS-scavenging metabolites and alterations in ROS metabolism, leading to lowered ROS levels and enhanced photosynthesis. Additionally, it modulates ion sequestration through V-ATPase accumulation, potentially contributing to the observed decrease in chloride content.
- MeSH
- Acremonium * metabolismus fyziologie MeSH
- Brassica napus mikrobiologie metabolismus fyziologie účinky léků MeSH
- fotosyntéza MeSH
- homeostáza * MeSH
- kyselina abscisová metabolismus MeSH
- oxidace-redukce * MeSH
- regulátory růstu rostlin * metabolismus MeSH
- rostlinné proteiny metabolismus genetika MeSH
- signální transdukce * MeSH
- solný stres fyziologie MeSH
- tolerance k soli * fyziologie MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- kyselina abscisová MeSH
- regulátory růstu rostlin * MeSH
- rostlinné proteiny MeSH
Sulfur (S) is an essential mineral nutrient for plant growth and development; it is important for primary and specialized plant metabolites that are crucial for biotic and abiotic interactions. Foliar S content varies up to 6-fold under a controlled environment, suggesting an adaptive value under certain natural environmental conditions. However, a major quantitative regulator of S content in Arabidopsis thaliana has not been identified yet, pointing to the existence of either additional genetic factors controlling sulfate/S content or of many minor quantitative regulators. Here, we use overlapping information of two separate ionomics studies to select groups of accessions with low, mid, and high foliar S content. We quantify series of metabolites, including anions (sulfate, phosphate, and nitrate), thiols (cysteine and glutathione), and seven glucosinolates, gene expression of 20 genes, sulfate uptake, and three biotic traits. Our results suggest that S content is tightly connected with sulfate uptake, the concentration of sulfate and phosphate anions, and glucosinolate and glutathione synthesis. Additionally, our results indicate that the growth of pathogenic bacteria is enhanced in the A. thaliana accessions containing higher S in their leaves, suggesting a complex regulation between S homeostasis, primary and secondary metabolism, and biotic pressures.
- Klíčová slova
- Arabidopsis thaliana, gene expression, glucosinolates, glutathione, natural variation, nutrients, sulfur,
- MeSH
- anionty metabolismus MeSH
- Arabidopsis * metabolismus MeSH
- fosfáty metabolismus MeSH
- glukosinoláty MeSH
- glutathion metabolismus MeSH
- proteiny huseníčku * metabolismus MeSH
- regulace genové exprese u rostlin MeSH
- síra metabolismus MeSH
- sírany metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- anionty MeSH
- fosfáty MeSH
- glukosinoláty MeSH
- glutathion MeSH
- proteiny huseníčku * MeSH
- síra MeSH
- sírany MeSH
Greenhouse gas (GHG) emissions have created a global climate crisis which requires immediate interventions to mitigate the negative effects on all aspects of life on this planet. As current agriculture and land use contributes up to 25% of total GHG emissions, plant scientists take center stage in finding possible solutions for a transition to sustainable agriculture and land use. In this article, the PlantACT! (Plants for climate ACTion!) initiative of plant scientists lays out a road map of how and in which areas plant scientists can contribute to finding immediate, mid-term, and long-term solutions, and what changes are necessary to implement these solutions at the personal, institutional, and funding levels.
- Klíčová slova
- agriculture, carbon sequestration, climate change, food safety, greenhouse gas emission, nitrogen use efficiency, water use efficiency,
- MeSH
- klimatické změny MeSH
- rostliny MeSH
- skleníkové plyny * analýza MeSH
- skleníkový efekt MeSH
- zemědělství * MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
- Názvy látek
- skleníkové plyny * MeSH
Hydroponic experiments were performed to examine the effect of prolonged sulfate limitation combined with cadmium (Cd) exposure in Arabidopsis thaliana and a potential Cd hyperaccumulator, Nicotiana tabacum. Low sulfate treatments (20 and 40 µM MgSO4) and Cd stress (4 µM CdCl2) showed adverse effects on morphology, photosynthetic and biochemical parameters and the nutritional status of both species. For example, Cd stress decreased NO3- root content under 20 µM MgSO4 to approximately 50% compared with respective controls. Interestingly, changes in many measured parameters, such as chlorophyll and carotenoid contents, the concentrations of anions, nutrients and Cd, induced by low sulfate supply, Cd exposure or a combination of both factors, were species-specific. Our data showed opposing effects of Cd exposure on Ca, Fe, Mn, Cu and Zn levels in roots of the studied plants. In A. thaliana, levels of glutathione, phytochelatins and glucosinolates demonstrated their distinct involvement in response to sub-optimal growth conditions and Cd stress. In shoot, the levels of phytochelatins and glucosinolates in the organic sulfur fraction were not dependent on sulfate supply under Cd stress. Altogether, our data showed both common and species-specific features of the complex plant response to prolonged sulfate deprivation and/or Cd exposure.
- Klíčová slova
- Arabidopsis thaliana, Cadmium, Heavy metal stress, Nicotiana tabacum, Sulfate,
- MeSH
- Arabidopsis * MeSH
- fytochelatiny MeSH
- glukosinoláty farmakologie MeSH
- kadmium toxicita MeSH
- kořeny rostlin MeSH
- potravní doplňky MeSH
- sírany farmakologie MeSH
- tabák MeSH
- živiny MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- fytochelatiny MeSH
- glukosinoláty MeSH
- kadmium MeSH
- sírany MeSH
The phytohormone cytokinin is implicated in a range of growth, developmental, and defense processes. A growing body of evidence supports a crosstalk between cytokinin and nutrient signaling pathways, such as nitrate availability. Cytokinin signaling regulates sulfur-responsive gene expression, but the underlying molecular mechanisms and their impact on sulfur-containing metabolites have not been systematically explored. Using a combination of genetic and pharmacological tools, we investigated the interplay between cytokinin signaling and sulfur homeostasis. Exogenous cytokinin triggered sulfur starvation-like gene expression accompanied by a decrease in sulfate and glutathione content. This process was uncoupled from the activity of the major transcriptional regulator of sulfate starvation signaling SULFUR LIMITATION 1 and an important glutathione-degrading enzyme, γ-glutamyl cyclotransferase 2;1, expression of which was robustly up-regulated by cytokinin. Conversely, glutathione accumulation was observed in mutants lacking the cytokinin receptor ARABIDOPSIS HISTIDINE KINASE 3 and in cytokinin-deficient plants. Cytokinin-deficient plants displayed improved root growth upon exposure to glutathione-depleting chemicals which was attributed to a higher capacity to maintain glutathione levels. These results shed new light on the interplay between cytokinin signaling and sulfur homeostasis. They position cytokinin as an important modulator of sulfur uptake, assimilation, and remobilization in plant defense against xenobiotics and root growth.
- Klíčová slova
- Arabidopsis thaliana, cytokinin, glutathione, nutrient homeostasis, sulfur metabolism, sulfur starvation, xenobiotic tolerance,
- MeSH
- cytokininy * MeSH
- glutathion MeSH
- metabolické sítě a dráhy MeSH
- síra * MeSH
- sírany MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- cytokininy * MeSH
- glutathion MeSH
- síra * MeSH
- sírany MeSH
Natural variation allows the investigation of both the fundamental functions of genes and their role in local adaptation. As one of the essential macronutrients, sulfur is vital for plant growth and development and also for crop yield and quality. Selenium and sulfur are assimilated by the same process, and although plants do not require selenium, plant-based selenium is an important source of this essential element for animals. Here, we report the use of linkage mapping in synthetic F2 populations and complementation to investigate the genetic architecture of variation in total leaf sulfur and selenium concentrations in a diverse set of Arabidopsis (Arabidopsis thaliana) accessions. We identify in accessions collected from Sweden and the Czech Republic two variants of the enzyme ADENOSINE 5'-PHOSPHOSULFATE REDUCTASE2 (APR2) with strongly diminished catalytic capacity. APR2 is a key enzyme in both sulfate and selenate reduction, and its reduced activity in the loss-of-function allele apr2-1 and the two Arabidopsis accessions Hodonín and Shahdara leads to a lowering of sulfur flux from sulfate into the reduced sulfur compounds, cysteine and glutathione, and into proteins, concomitant with an increase in the accumulation of sulfate in leaves. We conclude from our observation, and the previously identified weak allele of APR2 from the Shahdara accession collected in Tadjikistan, that the catalytic capacity of APR2 varies by 4 orders of magnitude across the Arabidopsis species range, driving significant differences in sulfur and selenium metabolism. The selective benefit, if any, of this large variation remains to be explored.
- MeSH
- Arabidopsis genetika metabolismus MeSH
- celogenomová asociační studie MeSH
- fenotyp MeSH
- frekvence genu MeSH
- genetická variace MeSH
- geneticky modifikované rostliny MeSH
- izoenzymy genetika metabolismus MeSH
- listy rostlin metabolismus MeSH
- oxidoreduktasy působící na donory sirných skupin genetika metabolismus MeSH
- proteiny huseníčku genetika metabolismus MeSH
- selen metabolismus MeSH
- síra metabolismus MeSH
- sírany metabolismus MeSH
- substituce aminokyselin MeSH
- výhonky rostlin metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
- Geografické názvy
- Česká republika MeSH
- Švédsko MeSH
- Názvy látek
- APR2 protein, Arabidopsis MeSH Prohlížeč
- izoenzymy MeSH
- oxidoreduktasy působící na donory sirných skupin MeSH
- proteiny huseníčku MeSH
- selen MeSH
- síra MeSH
- sírany MeSH
