Search results for " phosphorylation"
showing 10 items of 381 documents
Cold exposure enhances fat utilization but not non-esterified fatty acids, glycerol or catecholamines availability during submaximal walking and runn…
2013
Cold exposure modulates the use of carbohydrates and fat during exercise. This phenomenon has mostly been observed in controlled cycling studies, but not during walking and running when core temperature and oxygen consumption are controlled, as both may alter energy metabolism. This study aimed at examining energy substrate availability and utilization during walking and running in the cold when core temperature and oxygen consumption are maintained. Ten lightly clothed male subjects walked or ran for 60-min, at 50% and 70% of maximal oxygen consumption, respectively, in a climatic chamber set at 0°C or 22°C. Thermal, cardiovascular, and oxidative responses were measured every 15-…
Cytotoxic effects of oxysterols associated with human diseases: Induction of cell death (apoptosis and/or oncosis), oxidative and inflammatory activi…
2009
Oxysterols resulting from spontaneous or enzymatic oxidation of cholesterol are present in numerous foodstuffs and have been identified at increased levels in the plasma and the vascular walls of patients with cardiovascular diseases, especially in atherosclerotic lesions. Consequently, their role in lipid disorders is widely suspected, but they may also contribute to the development of important degenerative diseases such as Alzheimer's disease, Parkinson's disease, multiple sclerosis, osteoporosis, age-related macular degeneration, and cataract. Since these pathologies can be associated with the presence of apoptotic cells, oxidative and inflammatory processes, and lipid disorders, the ab…
Side effects of oxysterols: cytotoxicity, oxidation, inflammation, and phospholipidosis.
2008
Oxysterols are 27-carbon atom molecules resulting from autoxidation or enzymatic oxidation of cholesterol. They are present in numerous foodstuffs and have been demonstrated to be present at increased levels in the plasma of patients with cardiovascular diseases and in atherosclerotic lesions. Thus, their role in lipid disorders is widely suspected, and they might also be involved in important degenerative diseases such as Alzheimer's disease, osteoporosis, and age-related macular degeneration. Since atherosclerosis is associated with the presence of apoptotic cells and with oxidative and inflammatory processes, the ability of some oxysterols, especially 7-ketocholesterol and 7β-hydrox…
Direct evidence that FK506 inhibition of FcεRI-mediated exocytosis from RBL mast cells involves calcineurin
1998
eRI-mediated exocytosis of preformed mediators from mast cells and basophils (e.g. histamine, serotonin, beta-hexosaminidase) is sensitive to the immunosuppressants cyclosporin A and FK506 (IC 50 200 and 4 n M , respectively) but not rapamycin. The mechanism of inhibition does not appear to involve tyrosine phosphorylation, hydrolysis of inositol phosphates or calcium flux. Here we report experiments using a molecular approach to assess the role of calcineurin, a serine/threonine phosphatase thought to be the primary pharmacological target of these drugs. Calcineurin’s activity requires association of its catalytic (A) subunit with an intrinsic regulatory (B) subunit. We hypothesized that c…
Investigation of cancer drug resistance mechanisms by phosphoproteomics
2020
Abstract Cancer cell mutations can be identified by genomic and transcriptomic techniques. However, they are not sufficient to understand the full complexity of cancer heterogeneity. Analyses of proteins expressed in cancers and their modification profiles show how these mutations could be translated at the functional level. Protein phosphorylation is a major post-translational modification critical for regulating several cellular functions. The covalent addition of phosphate groups to serine, threonine, and tyrosine is catalyzed by protein kinases. Over the past years, kinases were strongly associated with cancer, thus inhibition of protein kinases emanated as novel cancer treatment. Howev…
Proteomic analysis of tyrosine phosphorylation induced by exogenous expression of oncogenic kinase fusions identified in lung adenocarcinoma.
2021
Kinase fusions are considered oncogenic drivers in numerous types of cancer. In lung adenocarcinoma 5-10% of patients harbor kinase fusions. The most frequently detected kinase fusion involves the Anaplastic Lymphoma Kinase (ALK) and Echinoderm Microtubule-associated protein-Like 4 (EML4). In addition, oncogenic kinase fusions involving the tyrosine kinases RET and ROS1 are found in smaller subsets of patients. In this study, we employed quantitative mass spectrometry-based phosphoproteomics to define the cellular tyrosine phosphorylation patterns induced by different oncogenic kinase fusions identified in patients with lung adenocarcinoma. We show that exogenous expression of the kinase fu…
Plant protein phosphorylation monitored by capillary liquid chromatography–element mass spectrometry
2007
Abstract Many essential cellular functions such as growth rate, motility, and metabolic activity are linked to reversible protein phosphorylation, since they are controlled by signaling cascades based mainly on phosphorylation/dephosphorylation events. Quantification of global or site-specific protein phosphorylation is not straightforward with standard proteomic techniques. The coupling of capillary liquid chromatography (μLC) with ICP-MS (inductively coupled plasma-mass spectrometry) is a method which allows a quantitative screening of protein extracts for their phosphorus and sulfur content, and thus provides access to the protein phosphorylation degree. In extension of a recent pilot st…
Saccharomyces cerevisiae Cytosolic Thioredoxins Control Glycolysis, Lipid Metabolism, and Protein Biosynthesis under Wine-Making Conditions.
2019
Thioredoxins are small proteins that regulate the cellular redox state, prevent oxidative damage, and play an active role in cell repair. Oxidative stress has proven to be of much relevance in biotechnological processes when the metabolism of Saccharomyces cerevisiae is mainly respiratory. During wine yeast starter production, active dry yeast cytosolic thioredoxin Trx2p is a key player in protecting metabolic enzymes from being oxidized by carbonylation. Less is known about the role of redox control during grape juice fermentation. A mutant strain that lacked both cytosolic thioredoxins, Trx1p and Trx2p, was tested for grape juice fermentation. Its growth and sugar consumption were greatly…
Mitochondrial proteomics profile points oxidative phosphorylation as main target for beauvericin and enniatin B mixture
2020
Abstract Beauvericin (BEA) and enniatin B (EN B) are non-legislated Fusarium mycotoxins usually found in cereal and cereal-based products all around the world. By the proteomic analysis of mitochondria enriched extracts from Jurkat cells exposed for 24 h to three concentrations of BEA:EN B (0.01–0.1–0.5 μM), a number of 1821 proteins (202 mitochondrial) were identified and relatively quantified. 340 proteins (59 mitochondrial) were statistically significant altered in our samples (Anova p-value ≤ 0.05 and fold change (FC) ≥1.5). The protein mitochondrial translational release factor 1 like (MTRF1L) was the most abundant protein in the three mycotoxin exposures studied. The mycotoxins mixtur…
Mitochondrial complex I: new insights from inhibitor assays
2000
The NADH:ubiquinone oxidoreductase (complex I) of the mitochondrial respiratory chain is by far the most complicated of the proton-translocating enzymes involved in the oxidative phosphorylation. Many clues regarding both electron transfer and proton translocation are still unknown. In this sense, inhibitor assays are relevant and useful pieces for elaborating a suitable model to explain the elusive bioenergetic mechanism of this enzyme. This short review presents the most recent advances in inhibitor studies and highlights the major controversies.