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Genomics Sep 2022Ralstonia solanacearum severely damages the growth of tobacco (Nicotiana tabacum L.) and causes great economic losses in tobacco production. To investigate the root...
Ralstonia solanacearum severely damages the growth of tobacco (Nicotiana tabacum L.) and causes great economic losses in tobacco production. To investigate the root metabolism and transcriptional characteristics of tobacco bacterial wilt susceptible variety Cuibi-1 (CB-1) and resistant new line KCB-1 (derived from an ethyl methanesulfonate (EMS) mutant of CB-1) after infestation with R. solanacearum, root metabolism and transcriptional characteristics were investigated using RNA-Seq and liquid chromatography-mass spectrometry (LC-MS). Differences in resistance between KCB-1 and CB-1 were observed in several aspects: (1) The phenylpropanoid pathway was the main pathway of resistance to bacterial wilt in KCB-1 compared with CB-1. (2) KCB-1 had more differential metabolic markers of disease resistance than CB-1 after infection with R. solanacearum. Among them, the differential coumarin-like metabolites that affect quorum sensing (QS) and biofilm formation of R. solanacearum differ in KCB-1 and CB-1. (3) KCB-1 inhibited production of the R. solanacearum metabolite putrescine, and the level of putrescine in tobacco was positively correlated with susceptibility. (4) Compared with CB-1, the metabolites of KCB-1 had less differential nitrogen sources during the infestation of R. solanacearum, which was detrimental to the growth and reproduction of R. solanacearum. (5) Both indole-3-acetic acid (IAA) and abscisic acid (ABA) in CB-1 and KCB-1 were involved in the response to R. solanacearum infestation, but the levels of IAA and ABA in KCB-1 were greater than in CB-1 at 24 h post inoculation (hpi). In conclusion, R. solanacearum caused reprogramming of both root metabolism and transcription in KCB-1 and CB-1, and the transcriptional and metabolic characteristics of resistant tobacco were more unfavorable to R. solanacearum.
Topics: Abscisic Acid; Coumarins; Ethyl Methanesulfonate; Nitrogen; Plant Diseases; Putrescine; Nicotiana; Transcriptome
PubMed: 36055574
DOI: 10.1016/j.ygeno.2022.110471 -
Langmuir : the ACS Journal of Surfaces... Mar 2020Coacervates are polymer-rich droplets that form through liquid-liquid phase separation in polymer solutions. Liquid-liquid phase separation and coacervation have...
Coacervates are polymer-rich droplets that form through liquid-liquid phase separation in polymer solutions. Liquid-liquid phase separation and coacervation have recently been shown to play an important role in the organization of biological systems. Such systems are highly dynamic and under continuous influence of enzymatic and chemical processes. However, it is still unclear how enzymatic and chemical reactions affect the coacervation process. Here, we present and characterize a system of enzymatically active coacervates containing spermine, RNA, free nucleotides, and the template independent RNA (de)polymerase PNPase. We find that these RNA coacervates display transient nonspherical shapes, and we systematically study how PNPase concentration, UDP concentration, and temperature affect coacervate morphology. Furthermore, we show that PNPase localizes predominantly into the coacervate phase and that its depolymerization activity in high-phosphate buffer causes coacervate degradation. Our observations of nonspherical coacervate shapes may have broader implications for the relationship between (bio)chemical activity and coacervate biology.
Topics: Polymers; RNA; Spermine; Temperature
PubMed: 31995710
DOI: 10.1021/acs.langmuir.9b02719 -
Molecular Cell Oct 2019A decline in polyamine levels with age has been implicated in the pathophysiology of aging, and nutritional supplementation of spermidine can reduce age-related...
A decline in polyamine levels with age has been implicated in the pathophysiology of aging, and nutritional supplementation of spermidine can reduce age-related pathology and increase lifespan in a number of different organisms. In this issue of Molecular Cell, Zhang and colleagues provide a mechanistic link between polyamines, autophagy, and aging.
Topics: Autophagy; Cellular Senescence; Longevity; Polyamines; Spermidine
PubMed: 31585103
DOI: 10.1016/j.molcel.2019.09.003 -
Biosensors Aug 2022The biogenic aliphatic polyamines (spermine, spermidine, and putrescine) are responsible for numerous cell functions, including cell proliferation, the stabilization of... (Review)
Review
The biogenic aliphatic polyamines (spermine, spermidine, and putrescine) are responsible for numerous cell functions, including cell proliferation, the stabilization of nucleic acid conformations, cell division, homeostasis, gene expression, and protein synthesis in living organisms. The change of polyamine concentrations in the urine or blood is usually related to the presence of malignant tumors and is regarded as a biomarker for the early diagnosis of cancer. Therefore, the detection of polyamine levels in physiological fluids can provide valuable information in terms of cancer diagnosis and in monitoring therapeutic effects. In this review, we summarize the recent advances in fluorescent methods for polyamine detection (supramolecular fluorescent sensing systems, fluorescent probes based on the chromophore reaction, fluorescent small molecules, and fluorescent nanoparticles). In addition, tumor polyamine-suppressing strategies (such as polyamine conjugate, polyamine analogs, combinations that target multiple components, spermine-responsive supramolecular chemotherapy, a combination of polyamine consumption and photodynamic therapy, etc.) are highlighted. We hope that this review promotes the development of more efficient polyamine detection methods and provides a comprehensive understanding of polyamine-based tumor suppressor strategies.
Topics: Humans; Neoplasms; Polyamines; Putrescine; Spermidine; Spermine
PubMed: 36005029
DOI: 10.3390/bios12080633 -
The New Phytologist Apr 2023Arginine decarboxylase (ADC)-mediated putrescine (Put) biosynthesis plays an important role in plant abiotic stress response. SNF1-related protein kinases 2s (SnRK2s)...
Arginine decarboxylase (ADC)-mediated putrescine (Put) biosynthesis plays an important role in plant abiotic stress response. SNF1-related protein kinases 2s (SnRK2s) and abscisic acid (ABA)-response element (ABRE)-binding factors (ABFs), are core components of the ABA signaling pathway involved in drought stress response. We previously reported that ADC of Poncirus trifoliata (PtrADC) functions in drought tolerance. However, whether and how SnRK2 and ABF regulate PtrADC to modulate putrescine accumulation under drought stress remains largely unclear. Herein, we employed a set of physiological, biochemical, and molecular approaches to reveal that a protein complex composed of PtrSnRK2.4 and PtrABF2 modulates putrescine biosynthesis and drought tolerance by directly regulating PtrADC. PtrABF2 was upregulated by dehydration in an ABA-dependent manner. PtrABF2 activated PtrADC expression by directly and specifically binding to the ABRE core sequence within its promoter and positively regulated drought tolerance via modulating putrescine accumulation. PtrSnRK2.4 interacts with and phosphorylates PtrABF2 at Ser93. PtrSnRK2.4-mediated PtrABF2 phosphorylation is essential for the transcriptional regulation of PtrADC. Besides, PtrSnRK2.4 was shown to play a positive role in drought tolerance by facilitating putrescine synthesis. Taken together, this study sheds new light on the regulatory module SnRK2.4-ABF2-ADC responsible for fine-tuning putrescine accumulation under drought stress, which advances our understanding on transcriptional regulation of putrescine synthesis.
Topics: Phosphorylation; Putrescine; Arabidopsis; Droughts; Plants, Genetically Modified; Abscisic Acid; Gene Expression Regulation, Plant; Arabidopsis Proteins; Protein Serine-Threonine Kinases; DNA-Binding Proteins; Transcription Factors
PubMed: 36210523
DOI: 10.1111/nph.18526 -
The Journal of Biological Chemistry Dec 2019Polyamines have essential roles in cell proliferation, DNA replication, transcription, and translation processes, with intracellular depletion of putrescine, spermidine,...
Polyamines have essential roles in cell proliferation, DNA replication, transcription, and translation processes, with intracellular depletion of putrescine, spermidine, and spermine resulting in cellular growth arrest and eventual death. Serum-free media for CHO-K1 cells require putrescine supplementation, because these cells lack the first enzyme of the polyamine production pathway, arginase. On the basis of this phenotype, we developed an arginase-based selection system. We transfected CHO-K1 cells with a bicistronic vector co-expressing GFP and arginase and selected cells in media devoid of l-ornithine and putrescine, resulting in mixed populations stably expressing GFP. Moreover, single clones in these selective media stably expressed GFP for a total of 42 generations. Using this polyamine starvation method, we next generated recombinant CHO-K1 cells co-expressing arginase and human erythropoietin (hEPO), which also displayed stable expression and healthy growth. The hEPO-expressing clones grew in commercial media, such as BalanCD and CHO-S serum-free media (SFM)-II, as well as in a defined serum-free, putrescine-containing medium for at least 9 passages (27 generations), with a minimal decrease in hEPO titer by the end of the culture. We observed a lack of arginase activity also in several CHO cell strains (CHO-DP12, CHO-S, and DUXB11) and other mammalian cell lines, including BHK21, suggesting broader utility of this selection system. In conclusion, we have established an easy-to-apply alternative selection system that effectively generates mammalian cell clones expressing biopharmaceutically relevant or other recombinant proteins without the need for any toxic selective agents. We propose that this system is applicable to mammalian cell lines that lack arginase activity.
Topics: Animals; Arginase; CHO Cells; Cell Line; Cricetulus; Erythropoietin; Polyamines; Putrescine; Recombinant Proteins
PubMed: 31666335
DOI: 10.1074/jbc.RA119.011162 -
Journal of Molecular Graphics &... Jul 2023Ongoing global pandemic caused by coronavirus (COVID-19) requires urgent development of vaccines, treatments, and diagnostic tools. Open reading frame 3a (ORF3a) from...
Ongoing global pandemic caused by coronavirus (COVID-19) requires urgent development of vaccines, treatments, and diagnostic tools. Open reading frame 3a (ORF3a) from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is considered to be a potential drug target for COVID-19 treatment. ORF3a is an accessory protein that plays a significant role in virus-host interactions and in facilitating host immune responses. Using putrescine, spermidine and spermine, an aliphatic polyamine for the activity suppression of ORF3a appears to be a promising approach in finding new targets for drug design. In this study, we explored the possible binding poses of polyamines to the ORF3a protein using a combination of various computational approaches i.e. pocket prediction, blind and site-specific molecular docking, molecular dynamics and ligand flooding simulations. The results showed that the tip of cytoplasmic domain and the upper tunnel of transmembrane domain of ORF3a provide a suitable binding site specific for the polyamines. MD simulations revealed the stability of spermidine binding in the upper tunnel pocket of ORF3a through salt bridge and hydrogen bond interactions between the amine groups of the ligand and negatively charged residues of ORF3a. These findings can be helpful in designing new therapeutic drugs.
Topics: Humans; SARS-CoV-2; COVID-19; Molecular Docking Simulation; Polyamines; Open Reading Frames; Spermidine; COVID-19 Drug Treatment; Ligands
PubMed: 37086515
DOI: 10.1016/j.jmgm.2023.108487 -
Cells Jan 2021In recent years, research on spermine (Spm) has turned up a lot of new information about this essential polyamine, especially as it is able to counteract damage from... (Review)
Review
In recent years, research on spermine (Spm) has turned up a lot of new information about this essential polyamine, especially as it is able to counteract damage from abiotic stresses. Spm has been shown to protect plants from a variety of environmental insults, but whether it can prevent the adverse effects of drought has not yet been reported. Drought stress increases endogenous Spm in plants and exogenous application of Spm improves the plants' ability to tolerate drought stress. Spm's role in enhancing antioxidant defense mechanisms, glyoxalase systems, methylglyoxal (MG) detoxification, and creating tolerance for drought-induced oxidative stress is well documented in plants. However, the influences of enzyme activity and osmoregulation on Spm biosynthesis and metabolism are variable. Spm interacts with other molecules like nitric oxide (NO) and phytohormones such as abscisic acid, salicylic acid, brassinosteroids, and ethylene, to coordinate the reactions necessary for developing drought tolerance. This review focuses on the role of Spm in plants under severe drought stress. We have proposed models to explain how Spm interacts with existing defense mechanisms in plants to improve drought tolerance.
Topics: Adaptation, Physiological; Droughts; Oxidative Stress; Plants; Spermine; Stress, Physiological
PubMed: 33525668
DOI: 10.3390/cells10020261 -
International Journal of Molecular... Jan 2024Ammonium and polyamines are essential nitrogen metabolites in all living organisms. Crosstalk between ammonium and polyamines through their metabolic pathways has been...
Ammonium and polyamines are essential nitrogen metabolites in all living organisms. Crosstalk between ammonium and polyamines through their metabolic pathways has been demonstrated in plants and animals, while no research has been directed to explore this relationship in algae or to investigate the underlying molecular mechanisms. Previous research demonstrated that high concentrations of ammonium and putrescine were among the active substances in bacteria-derived algicide targeting dinoflagellates, suggesting that the biochemical inter-connection and/or interaction of these nitrogen compounds play an essential role in controlling these ecologically important algal species. In this research, putrescine, ammonium, or a combination of putrescine and ammonium was added to cultures of three dinoflagellate species to explore their effects. The results demonstrated the dose-dependent and species-specific synergistic effects of putrescine and ammonium on these species. To further explore the molecular mechanisms behind the synergistic effects, transcriptome analysis was conducted on dinoflagellate treated with putrescine or ammonium vs. a combination of putrescine and ammonium. The results suggested that the synergistic effects of putrescine and ammonium disrupted polyamine homeostasis and reduced ammonium tolerance, which may have contributed to the cell death of . There was also transcriptomic evidence of damage to chloroplasts and impaired photosynthesis of . This research illustrates the molecular mechanisms underlying the synergistic effects of the major nitrogen metabolites, ammonium and putrescine, in dinoflagellates and provides direction for future studies on polyamine biology in algal species.
Topics: Animals; Putrescine; Dinoflagellida; Ammonium Compounds; Polyamines; Nitrogen
PubMed: 38279308
DOI: 10.3390/ijms25021306 -
The American Journal of Clinical... Jan 2019
Topics: Prospective Studies; Spermidine
PubMed: 30576412
DOI: 10.1093/ajcn/nqy222