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Antioxidants & Redox Signaling Sep 2017Trypanosomatids have a unique trypanothione-based thiol redox metabolism. The parasite-specific dithiol is synthesized from glutathione and spermidine, with...
AIMS
Trypanosomatids have a unique trypanothione-based thiol redox metabolism. The parasite-specific dithiol is synthesized from glutathione and spermidine, with glutathionylspermidine as intermediate catalyzed by trypanothione synthetase. In this study, we address the oxidative stress response of African trypanosomes with special focus on putative protein S-thiolation.
RESULTS
Challenging bloodstream Trypanosoma brucei with diamide, HO or hypochlorite results in distinct levels of reversible overall protein S-thiolation. Quantitative proteome analyses reveal 84 proteins oxidized in diamide-stressed parasites. Fourteen of them, including several essential thiol redox proteins and chaperones, are also enriched when glutathione/glutaredoxin serves as a reducing system indicating S-thiolation. In parasites exposed to HO, other sets of proteins are modified. Only three proteins are S-thiolated under all stress conditions studied in accordance with a highly specific response. HO causes primarily the formation of free disulfides. In contrast, in diamide-treated cells, glutathione, glutathionylspermidine, and trypanothione are almost completely protein bound. Remarkably, the total level of trypanothione is decreased, whereas those of glutathione and glutathionylspermidine are increased, indicating partial hydrolysis of protein-bound trypanothione. Depletion of trypanothione synthetase exclusively induces protein S-glutathionylation. Total mass analyses of a recombinant peroxidase treated with T(SH) and either diamide or hydrogen peroxide verify protein S-trypanothionylation as stable modification.
INNOVATION
Our data reveal for the first time that trypanosomes employ protein S-thiolation when exposed to exogenous and endogenous oxidative stresses and trypanothione, despite its dithiol character, forms protein-mixed disulfides.
CONCLUSION
The stress-specific responses shown here emphasize protein S-trypanothionylation and S-glutathionylation as reversible protection mechanism in these parasites. Antioxid. Redox Signal. 27, 517-533.
Topics: Diamide; Glutathione; Humans; Hydrogen Peroxide; Hypochlorous Acid; Oxidative Stress; Protein S; Proteome; Protozoan Proteins; Spermidine; Sulfhydryl Compounds; Trypanosoma brucei brucei
PubMed: 28338335
DOI: 10.1089/ars.2016.6947 -
Blood Coagulation & Fibrinolysis : An... Dec 2019: Protein S Tokushima (p.Lys196Glu) and two protein C gene variants (p.Arg189Trp, p.Lys193del) are hereditary thrombophilia in Japanese and Chinese populations,...
: Protein S Tokushima (p.Lys196Glu) and two protein C gene variants (p.Arg189Trp, p.Lys193del) are hereditary thrombophilia in Japanese and Chinese populations, respectively; however, their diagnosis by plasma analyses is difficult because of the type II deficiency phenotype. Three gene variant genotypes were examined in young Japanese women (n = 231). Plasma total protein S activity and total protein S antigen levels were measured using a total protein S assay system, protein C and protein S activities by clot-based methods, and protein C and free protein S antigen levels by latex agglutination methods. protein S Tokushima (p.Lys196Glu) and protein C p.Lys193del variants were prevalent among participants with allele frequencies of 1.08 and 0.86%, respectively, whereas any carrier of protein C p.Arg189Trp variant was not identified. The plasma phenotype of the type II deficiency of protein S Tokushima heterozygotes was demonstrated by decreased total protein S activity with a normal total protein S antigen level; however, the protein C activities of protein C p.Lys193del heterozygotes were within reference intervals, whereas their protein C antigen levels were elevated. We compared the diagnostic accuracy of the total protein S activity/total protein S antigen ratio for identifying protein S Tokushima heterozygotes with that of the clot-based protein S activity/free protein S antigen ratio and found that sensitivity and specificity of 100% each was only achieved by the former. Protein S Tokushima and protein C p.Lys193del are prevalent among young Japanese women, and a plasma analysis using the total protein S assay system is more accurate than the clot-based protein S activity/free protein S antigen ratio for diagnosing protein S Tokushima carriers.
Topics: Adult; Antigens; Asian People; Female; Gene Frequency; Heterozygote; Humans; Japan; Mutation; Phenotype; Plasma; Protein C; Protein S; Thrombophilia; Young Adult
PubMed: 31490209
DOI: 10.1097/MBC.0000000000000854 -
American Journal of Hematology May 2011Heterozygous deficiency of Protein S (PS) increases the risk for developing thrombosis. Many acquired conditions alter plasma PS levels. These complex interactions of PS... (Review)
Review
Heterozygous deficiency of Protein S (PS) increases the risk for developing thrombosis. Many acquired conditions alter plasma PS levels. These complex interactions of PS in plasma make it imperative that clinical PS assay limitations are understood so that the assays are reliable, reproducible and specific to diagnose true genetic abnormalities based on plasma phenotype alone. Unfortunately, the diagnosis of PS deficiency is difficult and complicated. Three basic assays can be utilized for assessing PS in plasma: PS activity assay, Free PS antigen assay, and Total PS antigen assay. This article will review these clinical assays and their associated problems. We also discuss the confounding and interfering factors that make it difficult to obtain an accurate diagnosis of PS deficiency.
Topics: Decision Trees; Diagnosis, Differential; Humans; Protein S; Protein S Deficiency
PubMed: 21523802
DOI: 10.1002/ajh.21992 -
Current Opinion in Chemical Biology Dec 2021Protein S-fatty acylation or S-palmitoylation is a reversible and regulated lipid post-translational modification (PTM) in eukaryotes. Loss-of-function mutagenesis... (Review)
Review
Protein S-fatty acylation or S-palmitoylation is a reversible and regulated lipid post-translational modification (PTM) in eukaryotes. Loss-of-function mutagenesis studies have suggested important roles for protein S-fatty acylation in many fundamental biological pathways in development, neurobiology, and immunity that are also associated with human diseases. However, the hydrophobicity and reversibility of this PTM have made site-specific gain-of-function studies more challenging to investigate. In this review, we summarize recent chemical biology approaches and methods that have enabled site-specific gain-of-function studies of protein S-fatty acylation and the investigation of the mechanisms and significance of this PTM in eukaryotic biology.
Topics: Acylation; Humans; Lipoylation; Protein Processing, Post-Translational; Protein S
PubMed: 34333222
DOI: 10.1016/j.cbpa.2021.06.004 -
International Journal of Hematology Apr 2012Plasma protein C is a serine protease zymogen that is transformed into the active, trypsin-like protease, activated protein C (APC), which can exert multiple activities.... (Review)
Review
Plasma protein C is a serine protease zymogen that is transformed into the active, trypsin-like protease, activated protein C (APC), which can exert multiple activities. For its anticoagulant action, APC causes inactivation of the procoagulant cofactors, factors Va and VIIIa, by limited proteolysis, and APC's anticoagulant activity is promoted by protein S, various lipids, high-density lipoprotein, and factor V. Hereditary heterozygous deficiency of protein C or protein S is linked to moderately increased risk for venous thrombosis, while a severe or total deficiency of either protein is linked to neonatal purpura fulminans. In recent years, the beneficial direct effects of APC on cells which are mediated by several specific receptors have become the focus of much attention. APC-induced signaling can promote multiple cytoprotective actions which can minimize injuries in various preclinical animal injury models. Remarkably, pharmacologic therapy using APC demonstrates substantial neuroprotective effects in various murine injury models, including ischemic stroke. This review summarizes the molecules that are central to the protein C pathways, the relationship of pathway deficiencies to venous thrombosis risk, and mechanisms for the beneficial effects of APC.
Topics: Animals; Anticoagulants; Cytoprotection; Enzyme Activation; Humans; Models, Molecular; Mutation; Protein C; Protein S; Receptors, Cell Surface; Signal Transduction; Thrombomodulin; Venous Thrombosis
PubMed: 22477541
DOI: 10.1007/s12185-012-1059-0 -
The Tohoku Journal of Experimental... Sep 2019A defect in clearance of apoptotic materials is pivotal in the pathogenesis of systemic lupus erythematosus (SLE). Protein S participates in the removal of apoptotic...
Plasma Free Protein S Is Correlated with Disease Activity, but not with Subclinical Atherosclerosis among Patients with Systemic Lupus Erythematosus: A Cross-Sectional Study.
A defect in clearance of apoptotic materials is pivotal in the pathogenesis of systemic lupus erythematosus (SLE). Protein S participates in the removal of apoptotic remnants and the anticoagulation pathway. The aim of the study was to clarify the relationship between plasma levels of free protein S and the disease activity or subclinical atherosclerosis in SLE. Free protein S was measured by an enzyme-linked immunosorbent assay, and patients were classified into two groups of free protein S levels: low (< 50%) and normal (≥ 50%). One hundred-eleven Korean female patients with SLE were enrolled, and the levels of free protein S were 67.4 ± 19.7%. Carotid plaque was detected in 25 (22.5%) patients. Twenty-one patients with low free protein S had lower hemoglobin (11.4 ± 1.4 vs. 12.5 ± 1.4 g/dL) and lymphocytes (1,221 ± 609 vs. 1,720 ± 1,097/µL), higher erythrocyte sedimentation rate (30.1 ± 20.6 vs. 20.8 ± 17.8 mm/h), and lower complement 3 (80.8 ± 27.6 vs. 103.4 ± 25.8 mg/dL) and complement 4 (15.6 ± 10.4 vs. 21.5 ± 7.6 mg/dL) than those with normal protein S. There was no significant difference in the proportion of patients with increased carotid artery intima-media thickness (> 4.6 mm) or with carotid artery plaque between two groups. The low levels of free protein S were associated with hemoglobin (OR = 0.64, p = 0.04) and complement 3 (OR = 0.96, p = 0.005). Free protein S is correlated with disease activity, but not with subclinical atherosclerosis in SLE.
Topics: Adult; Atherosclerosis; Cross-Sectional Studies; Female; Humans; Logistic Models; Lupus Erythematosus, Systemic; Multivariate Analysis; Protein S
PubMed: 31511453
DOI: 10.1620/tjem.249.1 -
International Journal of Molecular... Apr 2020Leber's hereditary optic neuropathy (LHON, MIM#535000) is the most common form of inherited optic neuropathies and mitochondrial DNA-related diseases. The pathogenicity...
Leber's hereditary optic neuropathy (LHON, MIM#535000) is the most common form of inherited optic neuropathies and mitochondrial DNA-related diseases. The pathogenicity of mutations in genes encoding components of mitochondrial Complex I is well established, but the underlying pathomechanisms of the disease are still unclear. Hypothesizing that oxidative stress related to Complex I deficiency may increase protein -glutathionylation, we investigated the proteome-wide -glutathionylation profiles in LHON ( 11) and control ( 7) fibroblasts, using the GluICAT platform that we recently developed. Glutathionylation was also studied in healthy fibroblasts ( 6) after experimental Complex I inhibition. The significantly increased reactive oxygen species (ROS) production in the LHON group by Complex I was shown experimentally. Among the 540 proteins which were globally identified as glutathionylated, 79 showed a significantly increased glutathionylation ( < 0.05) in LHON and 94 in Complex I-inhibited fibroblasts. Approximately 42% (33/79) of the altered proteins were shared by the two groups, suggesting that Complex I deficiency was the main cause of increased glutathionylation. Among the 79 affected proteins in LHON fibroblasts, 23% (18/79) were involved in energetic metabolism, 31% (24/79) exhibited catalytic activity, 73% (58/79) showed various non-mitochondrial localizations, and 38% (30/79) affected the cell protein quality control. Integrated proteo-metabolomic analysis using our previous metabolomic study of LHON fibroblasts also revealed similar alterations of protein metabolism and, in particular, of aminoacyl-tRNA synthetases. -glutathionylation is mainly known to be responsible for protein loss of function, and molecular dynamics simulations and 3D structure predictions confirmed such deleterious impacts on adenine nucleotide translocator 2 (ANT2), by weakening its affinity to ATP/ADP. Our study reveals a broad impact throughout the cell of Complex I-related LHON pathogenesis, involving a generalized protein stress response, and provides a therapeutic rationale for targeting -glutathionylation by antioxidative strategies.
Topics: Adenosine Triphosphate; Adult; Aged; Disease Susceptibility; Electron Transport Complex I; Female; Fibroblasts; Humans; Male; Middle Aged; Mitochondria; Models, Molecular; Optic Atrophy, Hereditary, Leber; Protein Conformation; Protein Processing, Post-Translational; Protein S; Proteome; Proteomics; Reactive Oxygen Species; Signal Transduction; Structure-Activity Relationship; Young Adult
PubMed: 32344771
DOI: 10.3390/ijms21083027 -
Neurobiology of Disease Dec 2015Nitric oxide (NO) is a gasotransmitter that impacts fundamental aspects of neuronal function in large measure through S-nitrosylation, a redox reaction that occurs on... (Review)
Review
Nitric oxide (NO) is a gasotransmitter that impacts fundamental aspects of neuronal function in large measure through S-nitrosylation, a redox reaction that occurs on regulatory cysteine thiol groups. For instance, S-nitrosylation regulates enzymatic activity of target proteins via inhibition of active site cysteine residues or via allosteric regulation of protein structure. During normal brain function, protein S-nitrosylation serves as an important cellular mechanism that modulates a diverse array of physiological processes, including transcriptional activity, synaptic plasticity, and neuronal survival. In contrast, emerging evidence suggests that aging and disease-linked environmental risk factors exacerbate nitrosative stress via excessive production of NO. Consequently, aberrant S-nitrosylation occurs and represents a common pathological feature that contributes to the onset and progression of multiple neurodegenerative disorders, including Alzheimer's, Parkinson's, and Huntington's diseases. In the current review, we highlight recent key findings on aberrant protein S-nitrosylation showing that this reaction triggers protein misfolding, mitochondrial dysfunction, transcriptional dysregulation, synaptic damage, and neuronal injury. Specifically, we discuss the pathological consequences of S-nitrosylated parkin, myocyte enhancer factor 2 (MEF2), dynamin-related protein 1 (Drp1), protein disulfide isomerase (PDI), X-linked inhibitor of apoptosis protein (XIAP), and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) under neurodegenerative conditions. We also speculate that intervention to prevent these aberrant S-nitrosylation events may produce novel therapeutic agents to combat neurodegenerative diseases.
Topics: Animals; Humans; Neurodegenerative Diseases; Protein S
PubMed: 25796565
DOI: 10.1016/j.nbd.2015.03.017 -
Blood Jul 2018
Topics: Humans; Hypoxia; Protein S; Thrombosis
PubMed: 30049732
DOI: 10.1182/blood-2018-06-854976 -
Annals of Laboratory Medicine Jan 2013Thrombophilia that is common among Caucasians is caused by genetic polymorphisms of coagulation factor V Leiden (R506Q) and prothrombin G20210A. Unlike that in... (Review)
Review
Thrombophilia that is common among Caucasians is caused by genetic polymorphisms of coagulation factor V Leiden (R506Q) and prothrombin G20210A. Unlike that in Caucasians, thrombophilia that is common in the Japanese and Chinese involve dysfunction of the activated protein C (APC) anticoagulant system caused by abnormal protein S and protein C molecules. Approximately 50% of Japanese and Chinese individuals who develop venous thrombosis have reduced activities of protein S. The abnormal sites causing the protein S molecule abnormalities are distributed throughout the protein S gene, PROS1. One of the most common abnormalities is protein S Tokushima (K155E), which accounts for about 30% of the protein S molecule abnormalities in the Japanese. Whether APC dysfunction occurs in other Asian countries is an important aspect of mapping thrombophilia among Asians. International surveys using an accurate assay system are needed to determine this.
Topics: Asian People; Blood Coagulation; Blood Proteins; Humans; Protein C; Protein S; Thrombophilia; Venous Thrombosis
PubMed: 23301217
DOI: 10.3343/alm.2013.33.1.8