Search results for "mediator"
showing 10 items of 339 documents
NO contributes to cadmium toxicity in Arabidopsis thaliana by mediating an iron deprivation response
2009
Nitric oxide (NO) functions as a cell-signaling molecule in plants. In particular, a role for NO in the regulation of iron homeostasis and in the plant response to toxic metals has been proposed. Here, we investigated the synthesis and the role of NO in plants exposed to cadmium (Cd(2+)), a nonessential and toxic metal. We demonstrate that Cd(2+) induces NO synthesis in roots and leaves of Arabidopsis (Arabidopsis thaliana) seedlings. This production, which is sensitive to NO synthase inhibitors, does not involve nitrate reductase and AtNOA1 but requires IRT1, encoding a major plasma membrane transporter for iron but also Cd(2+). By analyzing the incidence of NO scavenging or inhibition of …
S-nitrosylation: An emerging post-translational protein modification in plants
2011
International audience; Increasing evidences support the assumption that nitric oxide (NO) acts as a physiological mediator in plants. Understanding its pleiotropic effects requires a deep analysis of the molecular mechanisms underlying its mode of action. In the recent years, efforts have been made in the identification of plant proteins modified by NO at the post-translational level, notably by S-nitrosylation. This reversible process involves the formation of a covalent bond between NO and reactive cysteine residues. This research has now born fruits and numerous proteins regulated by S-nitrosylation have been identified and characterized. This review describes the basic principle of S-n…
Nitric oxide signalling in plants: interplays with Ca2+ and protein kinase
2008
International audience; Much attention has been paid to nitric oxide (NO)research since its discovery as a physiological mediator of plant defence responses. In recent years, newer roles have been attributed to NO, ranging from root development to stomatal closure. The molecular mechanisms underlying NO action in plants are just begun to emerge. The currently available data illustrate that NO can directly influence the activity of target proteins through nitrosylation and has the capacity to act as a Ca2+-mobilizing intracellular messenger. The interplay between NO and Ca2+ has important functional implications, expanding and enriching the possibilities for modulating transduction processes…
Nitric Oxide Signalling in Plants: Cross-Talk With Ca2+, Protein Kinases and Reactive Oxygen Species
2010
International audience; Nitric oxide (NO) is a gaseous free radical recognized as a ubiquitous signal transducer that contributes to various biological processes in animals. It exerts most of its effects by regulating the activities of various proteins including Ca2+ channels, protein kinases and transcription factors. In plants, studies conducted over the past ten years revealed that NO also functions as an endogenous mediator in diverse physiological processes ranging from root development to stomatal closure. Its biological role as an intracellular plant messenger molecule, however, remains poorly understood. Here, we review the molecular basis of NO signaling in animals and discuss curr…
What is the impact of a novel MED12 variant on syndromic conotruncal heart defects? Analysis of case report on two male sibs
2020
Abstract Background Syndromic congenital heart disease accounts for 30% of cases and can be determined by genetic, environmental or multifactorial causes. In many cases the etiology remains uncertain. Many known genes are responsible for specific morphopathogenetic mechanisms during the development of the heart whose alteration can determine specific phenotypes of cardiac malformations. Case presentation We report on two cases of association of conotruncal heart defect with facial dysmorphisms in sibs. In both cases the malformations’ identification occurred by ultrasound in the prenatal period. It was followed by prenatal invasive diagnosis. The genetic analysis revealed no rearrangements …
From lymphopoiesis to plasma cells differentiation, the age-related modifications of B cell compartment are influenced by “inflamm-ageing”
2017
Ageing is a complex process characterized by a general decline in physiological functions with increasing morbidity and mortality. The most important aspect of ageing is the chronic inflammatory status, named âinflamm-ageingâ, strictly associated with the deterioration of the immune function, termed âimmunosenescenceâ. Both are causes of increased susceptibility of elderly to infectious diseases, cancer, dementia, cardiovascular diseases and autoimmunity, and of a decreased response to vaccination. It has been widely demonstrated that ageing has a strong impact on the remodelling of the B cell branch of immune system. The first evident effect is the significant decrease in circulati…
The emerging role of Notch pathway in ageing: Focus on the related mechanisms in age-related diseases
2016
Notch signaling is an evolutionarily conserved pathway, which is fundamental for the development of all tissues, organs and systems of human body. Recently, a considerable and still growing number of studies have highlighted the contribution of Notch signaling in various pathological processes of the adult life, such as age-related diseases. In particular, the Notch pathway has emerged as major player in the maintenance of tissue specific homeostasis, through the control of proliferation, migration, phenotypes and functions of tissue cells, as well as in the cross-talk between inflammatory cells and the innate immune system, and in onset of inflammatory age-related diseases. However, until …
H-ferritin and proinflammatory cytokines are increased in the bone marrow of patients affected by macrophage activation syndrome
2017
Summary Macrophage activation syndrome (MAS) is hyperinflammatory life-threatening syndrome, associated typically with high levels of serum ferritin. This is an iron storage protein including heavy (H) and light (L) subunits, categorized on their molecular weight. The H-/L subunits ratio may be different in tissues, depending on the specific tissue and pathophysiological status. In this study, we analysed the bone marrow (BM) biopsies of adult MAS patients to assess the presence of: (i) H-ferritin and L-ferritin; (ii) CD68+/H-ferritin+ and CD68+/L-ferritin+; and (iii) interleukin (IL)-1β, tumour necrosis factor (TNF) and interferon (IFN)-γ. We also explored possible correlations of these re…
Oleanolic acid improves diet-induced obesity by modulating fat preference and inflammation in mice.
2018
Obesity, triggered by high-fat diet (HFD), is associated to altered gustatory perception of dietary lipids. Oleanolic acid (OLA), a triterpene, has been reported to exert anti-obesity effects in animal models. Hence, we investigated the role of OLA in the modulation of oro-sensory perception of lipids in control and HFD-induced obese mice. As expected, OLA-treated obese mice exhibited a decrease in body, liver, and visceral adipose tissue weights. OLA treatment improved glucose tolerance, insulin level, plasma lipopolysaccharide (LPS), and hepatic cholesterol and triglyceride concentrations. OLA-treated obese mice exhibited higher fat preference compared to untreated obese mice, probably du…
Nut1/Hos1 and Sas2/Rpd3 control the H3 acetylation of two different sets of osmotic stress-induced genes
2019
Epigenetic information is able to interact with the cellular environment and could be especially useful for reprograming gene expression in response to a physiological perturbation. In fact the genes induced or repressed by osmotic stress undergo significant changes in terms of the levels of various histone modifications, especially in the acetylation levels of histone H3. Exposing yeast to high osmolarity results in the activation of stress-activated protein kinase Hog1, which plays a central role in gene expression control. We evaluated the connection between the presence of Hog1 and changes in histone H3 acetylation in stress-regulated genes. We found a parallel increase in the acetylati…