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International Journal of Molecular... Apr 2020Ten articles published in the "Special Issue: Salicylic Acid Signalling in Plants" are summarized, in order to get a global picture about the mode of action of salicylic...
Ten articles published in the "Special Issue: Salicylic Acid Signalling in Plants" are summarized, in order to get a global picture about the mode of action of salicylic acid in plants, and about its interaction with other stress-signalling routes. Its ecological aspects and possible practical use are also discussed.
Topics: Acclimatization; Plant Development; Plant Growth Regulators; Plants; Salicylic Acid; Signal Transduction; Stress, Physiological
PubMed: 32290350
DOI: 10.3390/ijms21072655 -
Biomolecules May 2021Salicylic acid (SA) is an active secondary metabolite that occurs in bacteria, fungi, and plants. SA and its derivatives (collectively called salicylates) are... (Review)
Review
Salicylic acid (SA) is an active secondary metabolite that occurs in bacteria, fungi, and plants. SA and its derivatives (collectively called salicylates) are synthesized from chorismate (derived from shikimate pathway). SA is considered an important phytohormone that regulates various aspects of plant growth, environmental stress, and defense responses against pathogens. Besides plants, a large number of bacterial species, such as , , , , , , , and , have been reported to synthesize salicylates through the NRPS/PKS biosynthetic gene clusters. This bacterial salicylate production is often linked to the biosynthesis of small ferric-ion-chelating molecules, salicyl-derived siderophores (known as catecholate) under iron-limited conditions. Although bacteria possess entirely different biosynthetic pathways from plants, they share one common biosynthetic enzyme, isochorismate synthase, which converts chorismate to isochorismate, a common precursor for synthesizing SA. Additionally, SA in plants and bacteria can undergo several modifications to carry out their specific functions. In this review, we will systematically focus on the plant and bacterial salicylate biosynthesis and its metabolism.
Topics: Bacteria; Biosynthetic Pathways; Plant Growth Regulators; Plants; Salicylic Acid; Siderophores
PubMed: 34065121
DOI: 10.3390/biom11050705 -
Cell Sep 2020In plants, pathogen effector-triggered immunity (ETI) often leads to programmed cell death, which is restricted by NPR1, an activator of systemic acquired resistance....
In plants, pathogen effector-triggered immunity (ETI) often leads to programmed cell death, which is restricted by NPR1, an activator of systemic acquired resistance. However, the biochemical activities of NPR1 enabling it to promote defense and restrict cell death remain unclear. Here we show that NPR1 promotes cell survival by targeting substrates for ubiquitination and degradation through formation of salicylic acid-induced NPR1 condensates (SINCs). SINCs are enriched with stress response proteins, including nucleotide-binding leucine-rich repeat immune receptors, oxidative and DNA damage response proteins, and protein quality control machineries. Transition of NPR1 into condensates is required for formation of the NPR1-Cullin 3 E3 ligase complex to ubiquitinate SINC-localized substrates, such as EDS1 and specific WRKY transcription factors, and promote cell survival during ETI. Our analysis of SINCs suggests that NPR1 is centrally integrated into the cell death or survival decisions in plant immunity by modulating multiple stress-responsive processes in this quasi-organelle.
Topics: Arabidopsis; Arabidopsis Proteins; Cell Survival; Gene Expression Regulation, Plant; Plant Immunity; Salicylic Acid; Ubiquitination
PubMed: 32810437
DOI: 10.1016/j.cell.2020.07.016 -
Nature May 2022NPR1 is a master regulator of the defence transcriptome induced by the plant immune signal salicylic acid. Despite the important role of NPR1 in plant immunity,...
NPR1 is a master regulator of the defence transcriptome induced by the plant immune signal salicylic acid. Despite the important role of NPR1 in plant immunity, understanding of its regulatory mechanisms has been hindered by a lack of structural information. Here we report cryo-electron microscopy and crystal structures of Arabidopsis NPR1 and its complex with the transcription factor TGA3. Cryo-electron microscopy analysis reveals that NPR1 is a bird-shaped homodimer comprising a central Broad-complex, Tramtrack and Bric-à-brac (BTB) domain, a BTB and carboxyterminal Kelch helix bundle, four ankyrin repeats and a disordered salicylic-acid-binding domain. Crystal structure analysis reveals a unique zinc-finger motif in BTB for interacting with ankyrin repeats and mediating NPR1 oligomerization. We found that, after stimulation, salicylic-acid-induced folding and docking of the salicylic-acid-binding domain onto ankyrin repeats is required for the transcriptional cofactor activity of NPR1, providing a structural explanation for a direct role of salicylic acid in regulating NPR1-dependent gene expression. Moreover, our structure of the TGA3-NPR1-TGA3 complex, DNA-binding assay and genetic data show that dimeric NPR1 activates transcription by bridging two fatty-acid-bound TGA3 dimers to form an enhanceosome. The stepwise assembly of the NPR1-TGA complex suggests possible hetero-oligomeric complex formation with other transcription factors, revealing how NPR1 reprograms the defence transcriptome.
Topics: Arabidopsis; Arabidopsis Proteins; Basic-Leucine Zipper Transcription Factors; Cryoelectron Microscopy; Gene Expression Profiling; Gene Expression Regulation, Plant; Plant Immunity; Plant Proteins; Salicylic Acid; Transcription Factors
PubMed: 35545668
DOI: 10.1038/s41586-022-04699-w -
Anais Brasileiros de Dermatologia 2017Acne vulgaris is an extremely common condition affecting the pilosebaceous unit of the skin and characterized by presence of comedones, papules, pustules, nodules,... (Review)
Review
Acne vulgaris is an extremely common condition affecting the pilosebaceous unit of the skin and characterized by presence of comedones, papules, pustules, nodules, cysts, which might result in permanent scars. Acne vulgaris commonly involve adolescents and young age groups. Active acne vulgaris is usually associated with several complications like hyper or hypopigmentation, scar formation and skin disfigurement. Previous studies have targeted the efficiency and safety of local and systemic agents in the treatment of active acne vulgaris. Superficial chemical peeling is a skin-wounding procedure which might cause some potentially undesirable adverse events. This study was conducted to review the efficacy and safety of superficial chemical peeling in the treatment of active acne vulgaris. It is a structured review of an earlier seven articles meeting the inclusion and exclusion criteria. The clinical assessments were based on pretreatment and post-treatment comparisons and the role of superficial chemical peeling in reduction of papules, pustules and comedones in active acne vulgaris. This study showed that almost all patients tolerated well the chemical peeling procedures despite a mild discomfort, burning, irritation and erythema have been reported; also the incidence of major adverse events was very low and easily manageable. In conclusion, chemical peeling with glycolic acid is a well-tolerated and safe treatment modality in active acne vulgaris while salicylic acid peels is a more convenient for treatment of darker skin patients and it showed significant and earlier improvement than glycolic acid.
Topics: Acne Vulgaris; Chemexfoliation; Erythema; Glycolates; Humans; Keratolytic Agents; Salicylates; Salicylic Acid; Treatment Outcome
PubMed: 28538881
DOI: 10.1590/abd1806-4841.20175273 -
Plant Physiology Jan 2017Exosomes are extracellular vesicles (EVs) that play a central role in intercellular signaling in mammals by transporting proteins and small RNAs. Plants are also known...
Exosomes are extracellular vesicles (EVs) that play a central role in intercellular signaling in mammals by transporting proteins and small RNAs. Plants are also known to produce EVs, particularly in response to pathogen infection. The contents of plant EVs have not been analyzed, however, and their function is unknown. Here, we describe a method for purifying EVs from the apoplastic fluids of Arabidopsis (Arabidopsis thaliana) leaves. Proteomic analyses of these EVs revealed that they are highly enriched in proteins involved in biotic and abiotic stress responses. Consistent with this finding, EV secretion was enhanced in plants infected with Pseudomonas syringae and in response to treatment with salicylic acid. These findings suggest that EVs may represent an important component of plant immune responses.
Topics: Arabidopsis; Arabidopsis Proteins; Brefeldin A; Extracellular Vesicles; Heat-Shock Proteins; Immunity, Innate; Plant Leaves; Plants, Genetically Modified; Pseudomonas syringae; Qa-SNARE Proteins; Salicylic Acid; Triiodobenzoic Acids
PubMed: 27837092
DOI: 10.1104/pp.16.01253 -
International Journal of Molecular... Feb 2022In plants, salicylic acid (SA) is a hormone that mediates a plant's defense against pathogens. SA also takes an active role in a plant's response to various abiotic... (Review)
Review
In plants, salicylic acid (SA) is a hormone that mediates a plant's defense against pathogens. SA also takes an active role in a plant's response to various abiotic stresses, including chilling, drought, salinity, and heavy metals. In addition, in recent years, numerous studies have confirmed the important role of SA in plant morphogenesis. In this review, we summarize data on changes in root morphology following SA treatments under both normal and stress conditions. Finally, we provide evidence for the role of SA in maintaining the balance between stress responses and morphogenesis in plant development, and also for the presence of SA crosstalk with other plant hormones during this process.
Topics: Gene Expression Regulation, Plant; Plant Development; Plant Growth Regulators; Plant Roots; Plants; Salicylic Acid
PubMed: 35216343
DOI: 10.3390/ijms23042228 -
Current Opinion in Plant Biology Dec 2023The emergence of plant hormone signaling pathways is deeply intertwined with land plant evolution. In angiosperms, two plant hormones, salicylic Acid (SA) and Jasmonates... (Review)
Review
The emergence of plant hormone signaling pathways is deeply intertwined with land plant evolution. In angiosperms, two plant hormones, salicylic Acid (SA) and Jasmonates (JAs), play a key role in plant defense, where JAs-mediated defenses are typically activated in response to herbivores and necrotrophic pathogens, whereas SA is prioritized against hemi/biotrophic pathogens. Thus, studying the evolution of SA and JAs and their crosstalk is essential to understand the evolution of molecular plant-microbe interactions (EvoMPMI) in land plants. Recent advances in the evolution of SA and JAs biosynthesis, signaling, and crosstalk in land plants illustrated that the insight gained in angiosperms does not necessarily apply to non-seed plant lineages, where the receptors perceive different ligands and the hormones activate pathways independently on the canonical receptors. In this review, recent findings on the two main defense hormones (JAs and SA) in non-seed plants, including functional studies in the bryophyte model Marchantia polymorpha, will be discussed.
Topics: Salicylic Acid; Plant Diseases; Oxylipins; Cyclopentanes; Embryophyta; Plant Growth Regulators; Hormones; Gene Expression Regulation, Plant
PubMed: 37801737
DOI: 10.1016/j.pbi.2023.102470 -
Cells Sep 2022One grand challenge for studying plant biotic and abiotic stress responses is to optimize plant growth and plasticity under variable environmental constraints, which in... (Review)
Review
One grand challenge for studying plant biotic and abiotic stress responses is to optimize plant growth and plasticity under variable environmental constraints, which in the long run benefits agricultural production. However, efforts in promoting plant immunity are often accompanied by compromised morphological "syndromes" such as growth retardation, sterility, and reduced yield. Such a trade-off is dictated by complex signaling driven by secondary messengers and phytohormones. Salicylic acid (SA) is a well-known phytohormone essential for basal immunity and systemic acquired resistance. Interestingly, recent updates suggest that external environmental cues, nutrient status, developmental stages, primary metabolism, and breeding strategies attribute an additional layer of control over SA-dependent signaling, and, hence, plant performance against pathogens. In this review, these external and internal factors are summarized, focusing on their specific roles on SA biosynthesis and downstream signaling leading to immunity. A few considerations and future opportunities are highlighted to improve plant fitness with minimal growth compensation.
Topics: Gene Expression Regulation, Plant; Plant Diseases; Plant Growth Regulators; Plant Immunity; Plants; Salicylic Acid
PubMed: 36230947
DOI: 10.3390/cells11192985 -
Molecular Plant Jan 2020Salicylic acid (SA) has long been known to be essential for basal defense and systemic acquired resistance (SAR). N-Hydroxypipecolic acid (NHP), a recently discovered... (Review)
Review
Salicylic acid (SA) has long been known to be essential for basal defense and systemic acquired resistance (SAR). N-Hydroxypipecolic acid (NHP), a recently discovered plant metabolite, also plays a key role in SAR and to a lesser extent in basal resistance. Following pathogen infection, levels of both compounds are dramatically increased. Analysis of SA- or SAR-deficient mutants has uncovered how SA and NHP are biosynthesized. The completion of the SA and NHP biosynthetic pathways in Arabidopsis allowed better understanding of how they are regulated. In this review, we discuss recent progress on SA and NHP biosynthesis and their regulation in plant immunity.
Topics: Arabidopsis; Arabidopsis Proteins; Biosynthetic Pathways; Gene Expression Regulation, Plant; Pipecolic Acids; Plant Immunity; Salicylic Acid
PubMed: 31863850
DOI: 10.1016/j.molp.2019.12.008