scholarly journals The Age of Coumarins in Plant–Microbe Interactions

2019 ◽  
Vol 60 (7) ◽  
pp. 1405-1419 ◽  
Author(s):  
Ioannis A Stringlis ◽  
Ronnie de Jonge ◽  
Corn� M J Pieterse
Keyword(s):  
Plant Species ◽  
Stress Responses ◽  
Iron Uptake ◽  
Plant Pathogens ◽  
Current Knowledge ◽  
Phenylpropanoid Pathway ◽  
The Past ◽  
Microbe Interactions ◽  
Review Current

Abstract Coumarins are a family of plant-derived secondary metabolites that are produced via the phenylpropanoid pathway. In the past decade, coumarins have emerged as iron-mobilizing compounds that are secreted by plant roots and aid in iron uptake from iron-deprived soils. Members of the coumarin family are found in many plant species. Besides their role in iron uptake, coumarins have been extensively studied for their potential to fight infections in both plants and animals. Coumarin activities range from antimicrobial and antiviral to anticoagulant and anticancer. In recent years, studies in the model plant species tobacco and Arabidopsis have significantly increased our understanding of coumarin biosynthesis, accumulation, secretion, chemical modification and their modes of action against plant pathogens. Here, we review current knowledge on coumarins in different plant species. We focus on simple coumarins and provide an overview on their biosynthesis and role in environmental stress responses, with special attention for the recently discovered semiochemical role of coumarins in aboveground and belowground plant–microbe interactions and the assembly of the root microbiome.

scholarly journals HYPOXIA AND REPRODUCTIVE HEALTH: The presence and role of hypoxia in the endometrium

Reproduction ◽  
2021 ◽  
Vol 161 (1) ◽  
pp. F1-F17
Author(s):  
Rocío Martínez-Aguilar ◽  
Lucy E Kershaw ◽  
Jane J Reavey ◽  
Hilary O D Critchley ◽  
Jacqueline A Maybin
Keyword(s):  
Current Knowledge ◽  
Abnormal Uterine Bleeding ◽  
Future Research ◽  
Hypoxic Episode ◽  
Optimal Function ◽  
Pros And Cons ◽  
The Impact ◽  
Review Current

The endometrium is a multicellular tissue that is exquisitely responsive to the ovarian hormones. The local mechanisms of endometrial regulation to ensure optimal function are less well characterised. Transient physiological hypoxia has been proposed as a critical regulator of endometrial function. Herein, we review the literature on hypoxia in the non-pregnant endometrium. We discuss the pros and cons of animal models, human laboratory studies and novel in vivo imaging for the study of endometrial hypoxia. These research tools provide mounting evidence of a transient hypoxic episode in the menstrual endometrium and suggest that endometrial hypoxia may be present at the time of implantation. This local hypoxia may modify the inflammatory environment, influence vascular remodelling and modulate endometrial proliferation to optimise endometrial function. Finally, we review current knowledge of the impact of this hypoxia on endometrial pathologies, with a focus on abnormal uterine bleeding. Throughout the manuscript areas for future research are highlighted with the aim of concentrating research efforts to maximise future benefits for women and society.

Fungal Production and Manipulation of Plant Hormones

2018 ◽  
Vol 25 (2) ◽  
pp. 253-267 ◽  
Author(s):  
Sandra Fonseca ◽  
Dhanya Radhakrishnan ◽  
Kalika Prasad ◽  
Andrea Chini
Keyword(s):  
Stress Responses ◽  
Current Knowledge ◽  
Critical Role ◽  
Plant Defence ◽  
Pathogenic Fungi ◽  
Plant Responses ◽  
Defensive Strategies ◽  
Hormone Balance ◽  
Living Organisms

Living organisms are part of a highly interconnected web of interactions, characterised by species nurturing, competing, parasitizing and preying on one another. Plants have evolved cooperative as well as defensive strategies to interact with neighbour organisms. Among these, the plant-fungus associations are very diverse, ranging from pathogenic to mutualistic. Our current knowledge of plant-fungus interactions suggests a sophisticated coevolution to ensure dynamic plant responses to evolving fungal mutualistic/pathogenic strategies. The plant-fungus communication relies on a rich chemical language. To manipulate the plant defence mechanisms, fungi produce and secrete several classes of biomolecules, whose modeof- action is largely unknown. Upon perception of the fungi, plants produce phytohormones and a battery of secondary metabolites that serve as defence mechanism against invaders or to promote mutualistic associations. These mutualistic chemical signals can be co-opted by pathogenic fungi for their own benefit. Among the plant molecules regulating plant-fungus interaction, phytohormones play a critical role since they modulate various aspects of plant development, defences and stress responses. Intriguingly, fungi can also produce phytohormones, although the actual role of fungalproduced phytohormones in plant-fungus interactions is poorly understood. Here, we discuss the recent advances in fungal production of phytohormone, their putative role as endogenous fungal signals and how fungi manipulate plant hormone balance to their benefits.

scholarly journals The Significance of Flavonoids in the Process of Biological Nitrogen Fixation

2020 ◽  
Vol 21 (16) ◽  
pp. 5926
Author(s):  
Wei Dong ◽  
Yuguang Song
Keyword(s):  
Nitrogen Fixation ◽  
Plant Species ◽  
Biological Nitrogen Fixation ◽  
Molecular Basis ◽  
Phenylpropanoid Pathway ◽  
Rhizobium Spp ◽  
Microbial Symbionts ◽  
Biological Nitrogen ◽  
Do So

Nitrogen is essential for the growth of plants. The ability of some plant species to obtain all or part of their requirement for nitrogen by interacting with microbial symbionts has conferred a major competitive advantage over those plants unable to do so. The function of certain flavonoids (a group of secondary metabolites produced by the plant phenylpropanoid pathway) within the process of biological nitrogen fixation carried out by Rhizobium spp. has been thoroughly researched. However, their significance to biological nitrogen fixation carried out during the actinorhizal and arbuscular mycorrhiza–Rhizobium–legume interaction remains unclear. This review catalogs and contextualizes the role of flavonoids in the three major types of root endosymbiosis responsible for biological nitrogen fixation. The importance of gaining an understanding of the molecular basis of endosymbiosis signaling, as well as the potential of and challenges facing modifying flavonoids either quantitatively and/or qualitatively are discussed, along with proposed strategies for both optimizing the process of nodulation and widening the plant species base, which can support nodulation.

The Role of Symbioses in the Adaptation and Stress Responses of Marine Organisms

2020 ◽  
Vol 12 (1) ◽  
pp. 291-314 ◽  
Author(s):  
Amy Apprill
Keyword(s):  
Coral Reef ◽  
Significant Role ◽  
Stress Responses ◽  
Current Knowledge ◽  
Technological Development ◽  
Marine Organisms ◽  
Anthropogenic Change ◽  
Subject Knowledge ◽  
Coral Reef Ecosystems

Ocean ecosystems are experiencing unprecedented rates of climate and anthropogenic change, which can often initiate stress in marine organisms. Symbioses, or associations between different organisms, are plentiful in the ocean and could play a significant role in facilitating organismal adaptations to stressful ocean conditions. This article reviews current knowledge about the role of symbiosis in marine organismal acclimation and adaptation. It discusses stress and adaptations in symbioses from coral reef ecosystems, which are among the most affected environments in the ocean, including the relationships between corals and microalgae, corals and bacteria, anemones and clownfish, and cleaner fish and client fish. Despite the importance of this subject, knowledge of how marine organisms adapt to stress is still limited, and there are vast opportunities for research and technological development in this area. Attention to this subject will enhance our understanding of the capacity of symbioses to alleviate organismal stress in the oceans.

scholarly journals TOR coordinates with transcriptional and chromatin machinery to regulate thermotolerance and thermomemory

2020 ◽  
Author(s):  
Mohan Sharma ◽  
Muhammed Jamsheer K ◽  
Brihaspati Narayan Shukla ◽  
Manvi Sharma ◽  
Prakhar Awasthi ◽  
...  
Keyword(s):  
Stress Responses ◽  
Stress Signaling ◽  
Dependent Manner ◽  
Plant Fitness ◽  
Epigenetic Landscape ◽  
Tor Signaling ◽  
Promoter Regions ◽  
The Past ◽  
Adaptation To Heat

ABSTRACTGlobal warming exhibits profound effects on plant fitness and productivity. To withstand stress, plants sacrifice their growth and activate protective stress responses for ensuring survival. However, the switch between growth and stress is largely elusive. In the past decade, emerging role of Target of Rapamycin (TOR) has been studied linking energy and stress signaling. Here, we have identified an important role of Glc-TOR signaling in plant adaptation to heat stress (HS). Glc-TOR via the E2Fa signaling module regulates the transcription of heat shock factor genes through direct recruitment of E2Fa onto their promoter regions. Glc also epigenetically governs the transcription of core HS signaling genes in a TOR-dependent manner. TOR acts in concert with p300/CREB HISTONE ACETYLTRANSFERASE1 (HAC1) and dictates the epigenetic landscape of HS loci to regulate thermotolerance. Arabidopsis plants defective in TOR and HAC1 exhibited reduced thermotolerance with a decrease in expression of core HS signaling genes. In addition, TOR also promotes accumulation of histone H3K4me3 marks at the promoters of thermomemory-related genes and therefore, governs thermomemory. Collectively, our findings thus reveal a mechanistic framework in which Glc-TOR signaling through different modules determines the integration of stress and energy signaling to regulate thermotolerance and thermomemory.

scholarly journals Thyroid Hormone Plays an Important Role in Cardiac Function: From Bench to Bedside

2021 ◽  
Vol 12 ◽  
Author(s):  
Hiroyuki Yamakawa ◽  
Tomoko S. Kato ◽  
Jaeduk Yoshimura Noh ◽  
Shinsuke Yuasa ◽  
Akio Kawamura ◽  
...  
Keyword(s):  
Thyroid Hormones ◽  
Cardiac Function ◽  
Cardiovascular System ◽  
Antiarrhythmic Agent ◽  
Current Knowledge ◽  
Cardiac Contractility ◽  
The Body ◽  
The Past ◽  
Systolic And Diastolic Function

Thyroid hormones (THs) are synthesized in the thyroid gland, and they circulate in the blood to regulate cells, tissues, and organs in the body. In particular, they exert several effects on the cardiovascular system. It is well known that THs raise the heart rate and cardiac contractility, improve the systolic and diastolic function of the heart, and decrease systemic vascular resistance. In the past 30 years, some researchers have studied the molecular pathways that mediate the role of TH in the cardiovascular system, to better understand its mechanisms of action. Two types of mechanisms, which are genomic and non-genomic pathways, underlie the effects of THs on cardiomyocytes. In this review, we summarize the current knowledge of the action of THs in the cardiac function, the clinical manifestation and parameters of their hemodynamics, and treatment principles for patients with hyperthyroid- or hypothyroid-associated heart disease. We also describe the cardiovascular drugs that induce thyroid dysfunction and explain the mechanism underlying the thyroid toxicity of amiodarone, which is considered the most effective antiarrhythmic agent. Finally, we discuss the recent reports on the involvement of thyroid hormones in the regulation of myocardial regeneration and metabolism in the adult heart.

scholarly journals Considerações sobre hormônios e sexo / Considerations on hormones and sex

2021 ◽  
Vol 66 (1u) ◽  
pp. 1
Author(s):  
Sônia Maria Rolim Rosa Lima
Keyword(s):  
Sexual Function ◽  
Ovarian Function ◽  
Current Knowledge ◽  
Serum Concentrations ◽  
Local Synthesis ◽  
Low Concentrations ◽  
Potential Impact ◽  
Review Current ◽  
Selection Of

Os esteroides sexuais, em particular os estrogênios e os androgênios, representam papel fundamental, na modulação da função sexual feminina. As mulheres após a menopausa, devido ao declínio da função ovariana, são dependentes da síntese local de estrogênios nos tecidos alvo extragonadais. Mantendo-se o quadro carêncial ocorre progressivo estreitamento da vagina, e o sintoma genital mais comum é a secura por diminuição da transudação e da quantidade de muco cervical. Esses fenômenos explicam os processos encontrados no período do climatério ou qualquer período em que ocorra a carência estrogênica, característicos da falência hormonal: vaginite atrófica, leucorréia, prurido, dor e sangramento ao coito. Com relação aos androgênios, vários estudos investigaram associações entre androgênios e função sexual em mulheres. Muitos, mas não todos, identificam uma relação entre o desejo sexual e as concentrações séricas de androgênios circulantes. A variabilidade nos resultados provavelmente reflete as limitações em aferir com precisão suas baixas concentrações, o impacto potencial de outros esteroides, as diferenças no desenho do estudo, na seleção das participantes e nos parâmetros de função sexual. Neste artigo, revisamos o conhecimento atual sobre o papel dos estrogênios e androgênios e seu uso clínico em mulheres com declínio da função ovariana.Palavras chave: Hormônios sexuais, Esteroides, Androgênios, Pós-Menopausa, Disfunções sexuais fisiológicasABSTRACTSex steroids, in particular estrogens and androgens, play a fundamental role in the modulation of female sexual function. Postmenopausal women, due to the decline in ovarian function, are dependent on the local synthesis of estrogens in extragonadal target tissues. If the deficiency is maintained, progressive narrowing of the vagina occurs, and the most common genital symptom is dryness due to decreased transudation and the amount of cervical mucus. These phenomena explain the processes found during the climacteric period or any period in which estrogen deficiency occurs, which are characteristic of hormonal failure: atrophic vaginitis, leukorrhea, itching, pain and bleeding on intercourse. With regard to androgens, several studies have investigated associations between androgens and sexual function in women. Many, but not all, identify a relationship between sexual desire and serum concentrations of circulating androgens. The variability in the results probably reflects the limitations in accurately measuring the low concentrations of androgens in women, the potential impact of other steroids, the differences in the study design, in the selection of participants and in the parameters of sexual function. In this article, we review current knowledge about the role of estrogens and androgens and their clinical use in women with declining ovarian function.Keywords: Sex hormones, Steroids, Androgens, Postmenopause, Physiological sexual dysfunctions

scholarly journals MiRNAs in the Peri-Implantation Period: Contribution to Embryo–Maternal Communication in Pigs

2020 ◽  
Vol 21 (6) ◽  
pp. 2229 ◽  
Author(s):  
Monika M. Kaczmarek ◽  
Joanna Najmula ◽  
Maria M. Guzewska ◽  
Emilia Przygrodzka
Keyword(s):  
Current Knowledge ◽  
Mammalian Species ◽  
Embryo Implantation ◽  
Cell Communication ◽  
Large Family ◽  
Protein Coding ◽  
The Past ◽  
Domestic Livestock ◽  
Implantation Period

MicroRNAs (miRNAs) constitute a large family of noncoding RNAs, approximately 22 nucleotides long, which function as guide molecules in RNA silencing. Targeting most protein-coding transcripts, miRNAs are involved in nearly all developmental and pathophysiological processes in animals. To date, the regulatory roles of miRNAs in reproduction, such as fertilization, embryo development, implantation, and placenta formation, among others, have been demonstrated in numerous mammalian species, including domestic livestock such as pigs. Over the past years, it appeared that understanding the functions of miRNAs in mammalian reproduction can substantially improve our understanding of the biological challenges of successful reproductive performance. This review describes the current knowledge on miRNAs, specifically in relation to the peri-implantation period when the majority of embryonic mortality occurs in pigs. To present a broader picture of crucial peri-implantation events, we focus on the role of miRNA-processing machinery and miRNA–mRNA infarctions during the maternal recognition of pregnancy, leading to maintenance of the corpus luteum function and further embryo implantation. Furthermore, we summarize the current knowledge on cell-to-cell communication involving extracellular vesicles at the embryo–maternal interface in pigs. Finally, we discuss the potential of circulating miRNAs to serve as indicators of ongoing embryo–maternal crosstalk.

scholarly journals On transposons and totipotency

2020 ◽  
Vol 375 (1795) ◽  
pp. 20190339 ◽  
Author(s):  
Maria-Elena Torres-Padilla
Keyword(s):  
Large Scale ◽  
Current Knowledge ◽  
Regulation Of Gene Expression ◽  
Endogenous Retrovirus ◽  
Endogenous Retroviruses ◽  
Host Genome ◽  
The Past ◽  
Stage Of Development ◽  
Mammalian Genomes

Our perception of the role of the previously considered ‘selfish’ or ‘junk’ DNA has been dramatically altered in the past 20 years or so. A large proportion of this non-coding part of mammalian genomes is repetitive in nature, classified as either satellites or transposons. While repetitive elements can be termed selfish in terms of their amplification, such events have surely been co-opted by the host, suggesting by itself a likely altruistic function for the organism at the subject of such natural selection. Indeed numerous examples of transposons regulating the functional output of the host genome have been documented. Transposons provide a powerful framework for large-scale relatively rapid concerted regulatory activities with the ability to drive evolution. Mammalian totipotency has emerged as one key stage of development in which transposon-mediated regulation of gene expression has taken centre stage in the past few years. During this period, large-scale (epigenetic) reprogramming must be accomplished in order to activate the host genome. In mice and men, one particular element murine endogenous retrovirus with leucine tRNA primer (MERVL) (and its counterpart human ERVL (HERVL)) appears to have acquired roles as a key driving force in this process. Here, I will discuss and interpret the current knowledge and its implications regarding the role of transposons, particularly of long interspersed nuclear elements (LINE-1s) and endogenous retroviruses (ERVs), in the regulation of totipotency. This article is part of a discussion meeting issue ‘Crossroads between transposons and gene regulation’.

Role of Fur on cyanide tolerance of Pseudomonas pseudoalcaligenes CECT5344

2011 ◽  
Vol 39 (6) ◽  
pp. 1854-1858 ◽  
Author(s):  
Gracia Becerra ◽  
Rafael Blasco ◽  
Alberto Quesada ◽  
Faustino Merchán ◽  
M. Isabel Igeño
Keyword(s):  
Oxidative Stress ◽  
Iron Uptake ◽  
Current Knowledge ◽  
Tricarboxylic Acid Cycle ◽  
Pseudomonas Pseudoalcaligenes ◽  
Iron Deprivation ◽  
Essential Nutrient ◽  
High Concentrations ◽  
And Storage

Pseudomonas pseudoalcaligenes CECT5344 can be used in cyanide bioremediation processes because it grows at pH 9.5 using 2.0 mM cyanide at the sole nitrogen source. Cyanide strongly binds to metals creating iron-deprivation conditions. The bacterium responds to the presence of cyanide by inducing several processes such as siderophore synthesis for iron capture, cyanide-insensitive respiration system and defence mechanisms against oxidative stress. Since high concentrations of cyanide cause iron deficiency and because iron is an essential nutrient, bacterial growth in the presence of cyanide requires an efficient iron uptake. Fur is a global transcription factor that regulates a diversity of biological processes such as iron homoeostasis, TCA (tricarboxylic acid) cycle metabolism and oxidative stress response. Fur's regulation of iron uptake and storage genes should play a significant role in the lives of these bacteria. In the present review, current knowledge of Fur is summarized.

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