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Plant Signaling & Behavior Nov 2009Plant defensins are small, highly stable, cysteine-rich peptides that constitute a part of the innate immune system primarily directed against fungal pathogens.... (Review)
Review
Plant defensins are small, highly stable, cysteine-rich peptides that constitute a part of the innate immune system primarily directed against fungal pathogens. Biological activities reported for plant defensins include antifungal activity, antibacterial activity, proteinase inhibitory activity and insect amylase inhibitory activity. Plant defensins have been shown to inhibit infectious diseases of humans and to induce apoptosis in a human pathogen. Transgenic plants overexpressing defensins are strongly resistant to fungal pathogens. Based on recent studies, some plant defensins are not merely toxic to microbes but also have roles in regulating plant growth and development.
Topics: Animals; Anti-Bacterial Agents; Antifungal Agents; Defensins; Enzyme Inhibitors; Humans; Infections; Insecta; Plant Diseases; Plant Growth Regulators; Plant Proteins; Plants; Plants, Genetically Modified
PubMed: 20009545
DOI: 10.4161/psb.4.11.9755 -
BioMed Research International 2015Bioactive peptides are part of an innate response elicited by most living forms. In plants, they are produced ubiquitously in roots, seeds, flowers, stems, and leaves,... (Review)
Review
Bioactive peptides are part of an innate response elicited by most living forms. In plants, they are produced ubiquitously in roots, seeds, flowers, stems, and leaves, highlighting their physiological importance. While most of the bioactive peptides produced in plants possess microbicide properties, there is evidence that they are also involved in cellular signaling. Structurally, there is an overall similarity when comparing them with those derived from animal or insect sources. The biological action of bioactive peptides initiates with the binding to the target membrane followed in most cases by membrane permeabilization and rupture. Here we present an overview of what is currently known about bioactive peptides from plants, focusing on their antimicrobial activity and their role in the plant signaling network and offering perspectives on their potential application.
Topics: Anti-Infective Agents; Hydrolysis; Peptides; Plants; Signal Transduction
PubMed: 25815307
DOI: 10.1155/2015/102129 -
International Journal of Molecular... Oct 2015Since air pollution has been linked to a plethora of human health problems, strategies to improve air quality are indispensable. Despite the complexity in composition of... (Review)
Review
Since air pollution has been linked to a plethora of human health problems, strategies to improve air quality are indispensable. Despite the complexity in composition of air pollution, phytoremediation was shown to be effective in cleaning air. Plants are known to scavenge significant amounts of air pollutants on their aboveground plant parts. Leaf fall and runoff lead to transfer of (part of) the adsorbed pollutants to the soil and rhizosphere below. After uptake in the roots and leaves, plants can metabolize, sequestrate and/or excrete air pollutants. In addition, plant-associated microorganisms play an important role by degrading, detoxifying or sequestrating the pollutants and by promoting plant growth. In this review, an overview of the available knowledge about the role and potential of plant-microbe interactions to improve indoor and outdoor air quality is provided. Most importantly, common air pollutants (particulate matter, volatile organic compounds and inorganic air pollutants) and their toxicity are described. For each of these pollutant types, a concise overview of the specific contributions of the plant and its microbiome is presented. To conclude, the state of the art and its related future challenges are presented.
Topics: Air Pollutants; Biodegradation, Environmental; Microbiota; Plant Physiological Phenomena; Plants; Rhizosphere
PubMed: 26516837
DOI: 10.3390/ijms161025576 -
Current Opinion in Plant Biology Aug 2015Nitrogen-fixing symbioses between plants and bacteria are restricted to a few plant lineages. The plant partner benefits from these associations by gaining access to the... (Review)
Review
Nitrogen-fixing symbioses between plants and bacteria are restricted to a few plant lineages. The plant partner benefits from these associations by gaining access to the pool of atmospheric nitrogen. By contrast, other plant species, including all cereals, rely only on the scarce nitrogen present in the soil and what they can glean from associative bacteria. Global cereal yields from conventional agriculture are dependent on the application of massive levels of chemical fertilisers. Engineering nitrogen-fixing symbioses into cereal crops could in part mitigate the economic and ecological impacts caused by the overuse of fertilisers and provide better global parity in crop yields. Comparative phylogenetics and phylogenomics are powerful tools to identify genetic and genomic innovations behind key plant traits. In this review we highlight recent discoveries made using such approaches and we discuss how these approaches could be used to help direct the engineering of nitrogen-fixing symbioses into cereals.
Topics: Biological Evolution; Crops, Agricultural; Nitrogen Fixation
PubMed: 26123396
DOI: 10.1016/j.pbi.2015.06.003 -
International Journal of Molecular... Mar 2021Adaptation and response to environmental changes require dynamic and fast information distribution within the plant body. If one part of a plant is exposed to stress,... (Review)
Review
Adaptation and response to environmental changes require dynamic and fast information distribution within the plant body. If one part of a plant is exposed to stress, attacked by other organisms or exposed to any other kind of threat, the information travels to neighboring organs and even neighboring plants and activates appropriate responses. The information flow is mediated by fast-traveling small metabolites, hormones, proteins/peptides, RNAs or volatiles. Electric and hydraulic waves also participate in signal propagation. The signaling molecules move from one cell to the neighboring cell, via the plasmodesmata, through the apoplast, within the vascular tissue or-as volatiles-through the air. A threat-specific response in a systemic tissue probably requires a combination of different traveling compounds. The propagating signals must travel over long distances and multiple barriers, and the signal intensity declines with increasing distance. This requires permanent amplification processes, feedback loops and cross-talks among the different traveling molecules and probably a short-term memory, to refresh the propagation process. Recent studies show that volatiles activate defense responses in systemic tissues but also play important roles in the maintenance of the propagation of traveling signals within the plant. The distal organs can respond immediately to the systemic signals or memorize the threat information and respond faster and stronger when they are exposed again to the same or even another threat. Transmission and storage of information is accompanied by loss of specificity about the threat that activated the process. I summarize our knowledge about the proposed long-distance traveling compounds and discuss their possible connections.
Topics: Biological Transport; Biomarkers; Calcium; Disease Resistance; Electrophysiological Phenomena; Environment; Host-Pathogen Interactions; Light; Organ Specificity; Photosynthesis; Phytochrome; Plant Diseases; Plant Physiological Phenomena; Plants; RNA, Plant; Reactive Oxygen Species; Signal Transduction; Volatile Organic Compounds
PubMed: 33808792
DOI: 10.3390/ijms22063152 -
Biochimica Et Biophysica Acta Mar 2012Heat shock protein 90 (HSP90) is a highly conserved and essential molecular chaperone involved in maturation and activation of signaling proteins in eukaryotes. HSP90... (Review)
Review
Heat shock protein 90 (HSP90) is a highly conserved and essential molecular chaperone involved in maturation and activation of signaling proteins in eukaryotes. HSP90 operates as a dimer in a conformational cycle driven by ATP binding and hydrolysis. HSP90 often functions together with co-chaperones that regulate the conformational cycle and/or load a substrate "client" protein onto HSP90. In plants, immune sensing NLR (nucleotide-binding domain and leucine-rich repeat containing) proteins are among the few known client proteins of HSP90. In the process of chaperoning NLR proteins, co-chaperones, RAR1 and SGT1 function together with HSP90. Recent structural and functional analyses indicate that RAR1 dynamically controls conformational changes of the HSP90 dimer, allowing SGT1 to bridge the interaction between NLR proteins and HSP90. Here, we discuss the regulation of NLR proteins by HSP90 upon interaction with RAR1 and SGT1, emphasizing the recent progress in our understanding of the structure and function of the complex. This article is part of a Special Issue entitled: Heat Shock Protein 90 (HSP90).
Topics: HSP90 Heat-Shock Proteins; Models, Molecular; Molecular Chaperones; Plant Proteins; Plants; Structure-Activity Relationship
PubMed: 22001401
DOI: 10.1016/j.bbamcr.2011.09.016 -
International Journal of Molecular... Apr 2019Endophytic bacteria, which interact closely with their host, are an essential part of the plant microbiome. These interactions enhance plant tolerance to environmental... (Review)
Review
Endophytic bacteria, which interact closely with their host, are an essential part of the plant microbiome. These interactions enhance plant tolerance to environmental changes as well as promote plant growth, thus they have become attractive targets for increasing crop production. Numerous studies have aimed to characterise how endophytic bacteria infect and colonise their hosts as well as conferring important traits to the plant. In this review, we summarise the current knowledge regarding endophytic colonisation and focus on the insights that have been obtained from the mutants of bacteria and plants as well as 'omic analyses. These show how endophytic bacteria produce various molecules and have a range of activities related to chemotaxis, motility, adhesion, bacterial cell wall properties, secretion, regulating transcription and utilising a substrate in order to establish a successful interaction. Colonisation is mediated by plant receptors and is regulated by the signalling that is connected with phytohormones such as auxin and jasmonic (JA) and salicylic acids (SA). We also highlight changes in the expression of small RNAs and modifications of the cell wall properties. Moreover, in order to exploit the beneficial plant-endophytic bacteria interactions in agriculture successfully, we show that the key aspects that govern successful interactions remain to be defined.
Topics: Bacteria; Cell Wall; Endophytes; Plant Development; Plants; Signal Transduction
PubMed: 31010043
DOI: 10.3390/ijms20081947 -
Philosophical Transactions of the Royal... Sep 2016Land plants underpin a multitude of ecosystem functions, support human livelihoods and represent a critically important component of terrestrial biodiversity-yet many... (Review)
Review
Land plants underpin a multitude of ecosystem functions, support human livelihoods and represent a critically important component of terrestrial biodiversity-yet many tens of thousands of species await discovery, and plant identification remains a substantial challenge, especially where material is juvenile, fragmented or processed. In this opinion article, we tackle two main topics. Firstly, we provide a short summary of the strengths and limitations of plant DNA barcoding for addressing these issues. Secondly, we discuss options for enhancing current plant barcodes, focusing on increasing discriminatory power via either gene capture of nuclear markers or genome skimming. The former has the advantage of establishing a defined set of target loci maximizing efficiency of sequencing effort, data storage and analysis. The challenge is developing a probe set for large numbers of nuclear markers that works over sufficient phylogenetic breadth. Genome skimming has the advantage of using existing protocols and being backward compatible with existing barcodes; and the depth of sequence coverage can be increased as sequencing costs fall. Its non-targeted nature does, however, present a major informatics challenge for upscaling to large sample sets.This article is part of the themed issue 'From DNA barcodes to biomes'.
Topics: Biodiversity; DNA Barcoding, Taxonomic; Genome, Plant; Plants
PubMed: 27481790
DOI: 10.1098/rstb.2015.0338 -
Plant, Cell & Environment Feb 2014The expression of genes encoding various enzymes participating in photosynthetic and respiratory metabolism is regulated by light via the phytochrome system. While many... (Review)
Review
The expression of genes encoding various enzymes participating in photosynthetic and respiratory metabolism is regulated by light via the phytochrome system. While many photosynthetic, photorespiratory and some respiratory enzymes, such as the rotenone-insensitive NADH and NADPH dehydrogenases and the alternative oxidase, are stimulated by light, succinate dehydrogenase, subunits of the pyruvate dehydrogenase complex, cytochrome oxidase and fumarase are inhibited via the phytochrome mechanism. The effect of light, therefore, imposes limitations on the tricarboxylic acid cycle and on the mitochondrial electron transport coupled to ATP synthesis, while the non-coupled pathways become activated. Phytochrome-mediated regulation of gene expression also creates characteristic distribution patterns of photosynthetic, photorespiratory and respiratory enzymes across the leaf generating different populations of mitochondria, either enriched by glycine decarboxylase (in the upper part) or by succinate dehydrogenase (in the bottom part of the leaf).
Topics: Cell Respiration; Citric Acid Cycle; Electron Transport; Gene Expression Regulation, Plant; Glycine Dehydrogenase (Decarboxylating); Mitochondria; Mitochondrial Proteins; Oxidoreductases; Photosynthesis; Phytochrome; Plant Leaves; Plant Proteins; Plants; Succinate Dehydrogenase
PubMed: 23772790
DOI: 10.1111/pce.12155 -
Amino Acids Jul 2021Free amino acids (FAAs), the major constituents of the natural moisturizing factor (NMF), are very important for maintaining the moisture balance of human skin and their...
Free amino acids (FAAs), the major constituents of the natural moisturizing factor (NMF), are very important for maintaining the moisture balance of human skin and their deficiency results in dry skin conditions. There is a great interest in the identification and use of nature-based sources of these molecules for such cosmeceutical applications. The objective of the present study was, therefore, to investigate the FAA contents of selected Ethiopian plant and fungi species; and select the best sources so as to use them for the stated purpose. About 59 different plant species and oyster mushroom were included in the study and the concentrations of 27 FAAs were analyzed. Each sample was collected, lyophilized, extracted using aqueous solvent, derivatized with Fluorenylmethoxycarbonyl chloride (Fmoc-Cl) prior to solid-phase extraction and quantified using Liquid Chromatography Electrospray Ionization Tandem Mass Spectrometric (LC-ESI-MS/MS) system. All the 27 FAAs were detected in most of the samples. The dominant FAAs that are part of the NMF were found at sufficiently high concentration in the mushroom and some of the plants. This indicates that FAAs that could be included in the preparations for the management of dry skin condition can be obtained from a single natural resource and the use of these resources for the specified purpose have both economic and therapeutic advantage in addition to fulfilling customer needs.
Topics: Amino Acids; Chromatography, Liquid; Cosmeceuticals; Fungi; Humans; Plants; Skin; Tandem Mass Spectrometry
PubMed: 34106335
DOI: 10.1007/s00726-021-03008-5