1
|
Zajic DE, Podrabsky JE. Metabolomics analysis of annual killifish ( Austrofundulus limnaeus) embryos during aerial dehydration stress. Physiol Genomics 2020; 52:408-422. [PMID: 32776802 DOI: 10.1152/physiolgenomics.00072.2020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
The annual killifish, Austrofundulus limnaeus, survives in ephemeral ponds in the coastal deserts of Venezuela. Persistence through the dry season is dependent on drought-resistant eggs embedded in the pond sediments during the rainy season. The ability of these embryos to enter drastic metabolic dormancy (diapause) during normal development enables A. limnaeus to survive conditions lethal to most other aquatic vertebrates; critical to the survival of the species is the ability of embryos to survive months and perhaps years without access to liquid water. Little is known about the molecular mechanisms that aid in survival of the dry season. This study aims to gain insight into the mechanisms facilitating survival of dehydration stress due to aerial exposure by examining metabolite profiles of dormant and developing embryos. There is strong evidence for unique metabolic profiles based on developmental stage and length of aerial exposure. Actively developing embryos exhibit more robust changes; however, dormant embryos respond in an active manner and significantly alter their metabolic profile. A number of metabolites accumulate in aerial-exposed embryos that may play an important role in survival, including the identification of known antioxidants and neuroprotectants. In addition, a number of unique metabolites not yet discussed in the dehydration literature are identified, such as lanthionine and 2-hydroxyglutarate. Despite high oxygen availability, embryos accumulate the anaerobic end product lactate. This paper offers an overview of the metabolic changes occurring that may support embryonic survival during dehydration stress due to aerial incubation, which can be functionally tested using genetic and pharmacological approaches.
Collapse
Affiliation(s)
- Daniel E Zajic
- Department of Biology, Portland State University, Portland, Oregon.,Health, Human Performance, and Athletics Department, Linfield University, McMinnville, Oregon
| | | |
Collapse
|
2
|
Mao F, Yu K, He J, Zhou Q, Zhang G, Wang W, Li N, Zhang H, Jiang J. Real-time monitoring of electroreduction and labelling of disulfide-bonded peptides and proteins by mass spectrometry. Analyst 2019; 144:6898-6904. [PMID: 31638109 DOI: 10.1039/c9an01420a] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The accurate determination of disulfide bonds for protein identification is in high demand. In this study, a simple electrochemical-mass spectrometry (EC-MS) method that possesses advantages of real-time information, simultaneous disulfide bond electroreduction and tagging was developed. In this EC-MS, an ITO glass corner functions as a counter electrode and spray system, and allows the direct sampling of the droplet-scale reacting solution in real-time. The application of this method was successfully demonstrated by electrochemical reduction of oxidized glutathione (GSSG) with one disulfide bond as well as insulin with multiple disulfide bonds. The preferred electroreduction of intermolecular-bonded disulfides for insulin has been observed and the intramolecular bond was not favored. Moreover, simultaneously tagging the formed thiol residues from electroreduction of GSSG using electrogenerated intermediates such as dopamine orthoquinone (DQ) and benzoquinone (Q) was performed. A proof-of-concept was also demonstrated with a large molecule, β-lactoglobulin A. The relationship between signal strength and operating parameters was also studied. This method successfully detected the reduction reaction of the disulfide bond in the polypeptide and protein. The detection limit (S/N ≥ 3) is 0.398 μg mL-1. These results suggest that this EC-MS platform can count cysteine moieties in proteins using a single drop of sample and in real-time and is promising for protein identification experiments.
Collapse
Affiliation(s)
- Fengjiao Mao
- School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, Shandong 264209, P.R. China.
| | | | | | | | | | | | | | | | | |
Collapse
|
3
|
Sindhu R, Manonmani H. Expression and characterization of recombinant l -asparaginase from Pseudomonas fluorescens. Protein Expr Purif 2018; 143:83-91. [DOI: 10.1016/j.pep.2017.09.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Revised: 08/18/2017] [Accepted: 09/19/2017] [Indexed: 10/18/2022]
|
4
|
Nichenametla SN, Mattocks DAL, Malloy VL, Pinto JT. Sulfur amino acid restriction-induced changes in redox-sensitive proteins are associated with slow protein synthesis rates. Ann N Y Acad Sci 2018; 1418:80-94. [PMID: 29377163 DOI: 10.1111/nyas.13556] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 10/02/2017] [Accepted: 10/27/2017] [Indexed: 12/29/2022]
Abstract
The mechanisms underlying life span extension by sulfur amino acid restriction (SAAR) are unclear. Cysteine and methionine are essential for the biosynthesis of proteins and glutathione (GSH), a major redox buffer in the endoplasmic reticulum (ER). We hypothesized that SAAR alters protein synthesis by modulating the redox milieu. Male F344-rats were fed control (CD: 0.86% methionine without cysteine) and SAAR diets (0.17% methionine without cysteine) for 12 weeks. Growth rates, food intake, cysteine and GSH levels, proteins associated with redox status and translation, and fractional protein synthesis rates (FSRs) were determined in liver. Despite a 40% higher food intake, growth rates for SAAR rats were 27% of those fed CD. Hepatic free cysteine in SAAR rats was 55% compared with CD rats. SAAR altered tissue distribution of GSH, as hepatic and erythrocytic levels were 56% and 196% of those in CD rats. Lower GSH levels did not induce ER stress (i.e., unchanged expression of Xbp1s , Chop, and Grp78), but activated PERK and its substrates eIF2-α and NRF2. SAAR-induced changes in translation-initiation machinery (higher p-eIF2-α and 4E-BP1, and lower eIF4G-1) resulted in slower protein synthesis rates (53% of CD). Proteins involved in the antioxidant response (NRF2, KEAP1, GCLM, and NQO1) and protein folding (PDI and ERO1-α) were increased in SAAR. Lower FSR and efficient protein folding might be improving proteostasis in SAAR.
Collapse
Affiliation(s)
| | | | - Virginia L Malloy
- Orentreich Foundation for the Advancement of Science, Cold Spring, New York
| | - John T Pinto
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, New York
| |
Collapse
|
5
|
Tshabalala TN, Tomescu MS, Prior A, Balakrishnan V, Sayed Y, Dirr HW, Achilonu I. Energetics of Glutathione Binding to Human Eukaryotic Elongation Factor 1 Gamma: Isothermal Titration Calorimetry and Molecular Dynamics Studies. Protein J 2016; 35:448-458. [PMID: 27844275 DOI: 10.1007/s10930-016-9688-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The energetics of ligand binding to human eukaryotic elongation factor 1 gamma (heEF1γ) was investigated using reduced glutathione (GSH), oxidised glutathione (GSSG), glutathione sulfonate and S-hexylglutathione as ligands. The experiments were conducted using isothermal titration calorimetry, and the findings were supported using computational studies. The data show that the binding of these ligands to heEF1γ is enthalpically favourable and entropically driven (except for the binding of GSSG). The full length heEF1γ binds GSSG with lower affinity (K d = 115 μM), with more hydrogen-bond contacts (ΔH = -73.8 kJ/mol) and unfavourable entropy (-TΔS = 51.7 kJ/mol) compared to the glutathione transferase-like N-terminus domain of heEF1γ, which did not show preference to any specific ligand. Computational free binding energy calculations from the 10 ligand poses show that GSSG and GSH consistently bind heEF1γ, and that both ligands bind at the same site with a folded bioactive conformation. This study reveals the possibility that heEF1γ is a glutathione-binding protein.
Collapse
Affiliation(s)
- Thabiso N Tshabalala
- Protein Structure-Function Research Unit, School of Molecular and Cell Biology, University of the Witwatersrand, Johannesburg, 2050, South Africa
| | - Mihai-Silviu Tomescu
- Protein Structure-Function Research Unit, School of Molecular and Cell Biology, University of the Witwatersrand, Johannesburg, 2050, South Africa
| | - Allan Prior
- School of Chemistry, University of the Witwatersrand, Johannesburg, 2050, South Africa
| | - Vijayakumar Balakrishnan
- Protein Structure-Function Research Unit, School of Molecular and Cell Biology, University of the Witwatersrand, Johannesburg, 2050, South Africa
| | - Yasien Sayed
- Protein Structure-Function Research Unit, School of Molecular and Cell Biology, University of the Witwatersrand, Johannesburg, 2050, South Africa
| | - Heini W Dirr
- Protein Structure-Function Research Unit, School of Molecular and Cell Biology, University of the Witwatersrand, Johannesburg, 2050, South Africa
| | - Ikechukwu Achilonu
- Protein Structure-Function Research Unit, School of Molecular and Cell Biology, University of the Witwatersrand, Johannesburg, 2050, South Africa.
| |
Collapse
|
6
|
Kranner I, Grill D. Significance of Thiol-Disulfide Exchange in Resting Stages of Plant Development. ACTA ACUST UNITED AC 2014. [DOI: 10.1111/j.1438-8677.1996.tb00864.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
7
|
Endres K, Reinhardt S. ER-stress in Alzheimer's disease: turning the scale? AMERICAN JOURNAL OF NEURODEGENERATIVE DISEASE 2013; 2:247-265. [PMID: 24319643 PMCID: PMC3852565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Accepted: 11/05/2013] [Indexed: 06/03/2023]
Abstract
Pathogenic mechanisms of Alzheimer's disease (AD) are intensely investigated as it is the most common form of dementia and burdens society by its costs and social demands. While key molecules such as A-beta peptides and tau have been identified decades ago, it is still enigmatic what drives the disease in its sporadic manifestation. Synthesis of A-beta peptides as well as phosphorylation of tau proteins comprise normal cellular functions and occur in principle in the healthy as well as in dementia-affected persons. Dyshomeostasis of Amyloid Precursor Protein (APP) cleavage, energy metabolism or kinase/phosphatase activity due to stressors has been suggested as a trigger of the disease. One way for cells to escape stress based on dysfunction of ER is the unfolded protein response - the UPR. This pathway is composed out of three different routes that differ in proteins involved, targets and consequences for cell fate: activation of transmembrane ER resident kinases IRE1-alpha and PERK or monomerization of membrane-anchored activating transcription factor 6 (ATF6) induce activation of versatile transcription factors (XBP-1, eIF2-alpha/ATF4 and ATF6 P50). These bind to specific DNA sequences on target gene promoters and on one hand attenuate general ER-prone protein synthesis and on the other equip the cell with tools to de-stress. If cells fail in stress compensation, this signaling also is able to evoke apoptosis. In this review we summarized knowledge on how APP processing and phosphorylation of tau might be influenced by ER-stress signaling. In addition, we depicted the effects UPR itself seems to have on molecules closely related to AD and describe what is known about UPR in AD animal models as well as in human patients.
Collapse
Affiliation(s)
- Kristina Endres
- Department of Psychiatry and Psychotherapy, Clinical Research Group, University Medical Centre Johannes Gutenberg-University Mainz Untere Zahlbacher Str. 8, D-55131 Mainz, Germany
| | | |
Collapse
|
8
|
Abstract
β-Cell death is an important pathogenic component of both type 1 and type 2 diabetes. Recent findings indicate that cell signalling pathways emanating from the endoplasmic reticulum (ER) play an important role in the regulation of β-cell death during the progression of diabetes. Homeostasis within the ER must be maintained to produce properly folded secretory proteins, such as insulin, in response to the body's need for them. However, the sensitive protein-folding environment in the ER can be perturbed by genetic and environmental factors leading to ER stress. To counteract ER stress, β-cells activate cell signalling pathways termed the unfolded protein response (UPR). The UPR functions as a binary switch between life and death, regulating both survival and death effectors. The outcome of this switch depends on the nature of the ER stress condition, the regulation of UPR activation and the expression and activation of survival and death components. This review discusses the mechanisms and the components in this switch and highlights the roles of this UPR's balancing act between life and death in β-cells.
Collapse
Affiliation(s)
- Christine M. Oslowski
- Program in Gene Function and Expression, University of Massachusetts Medical School, Worcester, MA 01605, U.S.A
| | - Fumihiko Urano
- Program in Gene Function and Expression, University of Massachusetts Medical School, Worcester, MA 01605, U.S.A
- Program in Molecular Medicine University of Massachusetts Medical School, Worcester, MA 01605, U.S.A
| |
Collapse
|
9
|
Bandgar BP, Gawande SS, Warangkar SC, Totre JV. Silica-supported fluoroboric acid (HBF4–SiO2) catalyzed highly productive synthesis of thiomorpholides as activators of l-asparaginase as well as the antioxidant agent. Bioorg Med Chem 2010; 18:3618-24. [DOI: 10.1016/j.bmc.2010.03.033] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2010] [Revised: 03/12/2010] [Accepted: 03/13/2010] [Indexed: 11/25/2022]
|
10
|
Oslowski CM, Urano F. The binary switch between life and death of endoplasmic reticulum-stressed beta cells. Curr Opin Endocrinol Diabetes Obes 2010; 17:107-12. [PMID: 20125004 PMCID: PMC2898716 DOI: 10.1097/med.0b013e3283372843] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
PURPOSE OF REVIEW beta-Cell death is an important pathogenic component of both type 1 and type 2 diabetes. However, the specific molecular pathways and interactions involved in this process are not completely understood. Increasing evidence indicates that a type of cell stress called endoplasmic reticulum stress (ER stress) plays an important role in beta-cell death. In the present article, we discuss a potential paradigm of ER stress-mediated beta-cell death. RECENT FINDINGS Upon ER stress conditions, a signaling network termed the unfolded protein response (UPR) is activated. The UPR regulates adaptive effectors to attenuate ER stress and restore ER homeostasis promoting cell survival. Paradoxically the UPR also regulates apoptotic effectors. When adaptive effectors fail to attenuate ER stress, these apoptotic effectors take into effect leading to cell death. The nature of this switch between life and death is currently under study. SUMMARY Depending on the nature of the stress condition, the UPR either protects beta cells or promotes their death. The mechanisms of this switch are not well understood but involve the balance between adaptive and apoptotic factors regulated by the UPR. In the present article, we review examples of this UPR balancing act between life and death and the potential mechanisms involved.
Collapse
Affiliation(s)
- Christine M. Oslowski
- Program in Gene Function and Expression, University of Massachusetts Medical School, Worcester, MA 01605, U.S.A
| | - Fumihiko Urano
- Program in Gene Function and Expression, University of Massachusetts Medical School, Worcester, MA 01605, U.S.A
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, U.S.A
| |
Collapse
|
11
|
Warangkar SC, Khobragade CN. Purification, Characterization, and Effect of Thiol Compounds on Activity of the Erwinia carotovora L-Asparaginase. Enzyme Res 2009; 2010:165878. [PMID: 21048860 PMCID: PMC2956972 DOI: 10.4061/2010/165878] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2009] [Accepted: 07/31/2009] [Indexed: 11/20/2022] Open
Abstract
L-asparaginase was extracted from Erwinia carotovora and purified by ammonium sulfate fractionation (60–70%), Sephadex G-100, CM cellulose, and DEAE sephadex chromatography. The apparent Mr of enzyme under nondenaturing and denaturing conditions was 150 kDa and 37 ± 0.5 kDa, respectively. L-asparaginase activity was studied in presence of thiols, namely, L-cystine (Cys), L-methionine (Met), N-acetyl cysteine (NAC), and reduced glutathione (GSH). Kinetic parameters in presence of thiols (10–400 μM) showed an increase in Vmax values (2000, 2223, 2380, 2500, and control 1666.7 μmoles mg−1min−1) and a decrease in Km values (0.086, 0.076, 0.062, 0.055 and control 0.098 mM) indicating nonessential mode of activation. KA values displayed propensity to bind thiols. A decrease in Vmax/Km ratio in concentration plots showed inverse relationship between free thiol groups (NAC and GSH) and bound thiol group (Cys and Met). Enzyme activity was enhanced in presence of thiol protecting reagents like dithiothreitol (DTT), 2-mercaptoethanol (2-ME), and GSH, but inhibited by p-chloromercurybenzoate (PCMB) and iodoacetamide (IA).
Collapse
Affiliation(s)
- Suchita C Warangkar
- Biotechnology Research Laboratory, School of Life Sciences, Swami Ramanand Teerth Marathwada University, Nanded 431606, India
| | | |
Collapse
|
12
|
Hamilton GA. Peroxisomal oxidases and suggestions for the mechanism of action of insulin and other hormones. ADVANCES IN ENZYMOLOGY AND RELATED AREAS OF MOLECULAR BIOLOGY 2006; 57:85-178. [PMID: 2863924 DOI: 10.1002/9780470123034.ch2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
|
13
|
Wells WW, Yang Y, Deits TL, Gan ZR. Thioltransferases. ADVANCES IN ENZYMOLOGY AND RELATED AREAS OF MOLECULAR BIOLOGY 2006; 66:149-201. [PMID: 8430514 DOI: 10.1002/9780470123126.ch4] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
A family of small molecular weight proteins with thiol-disulfide exchange activity have been discovered, widely distributed from E. coli to mammalian systems, called thioltransferases or glutaredoxins. There are no substantiated reports of thioltransferases-glutaredoxins in plants; however, partially purified dehydroascorbate reductase from peas had thiol-disulfide exchange catalytic activity using glutathione as reductant and S-sulfocysteine as thiosulfate cosubstrate (unpublished data). Thus, this class of proteins is universally distributed. Based on mutagenesis studies, a sequence of Cys-Pro-Tyr(Phe)-Cys- followed by Arg-Lys- or Lys alone is critical for both the thiol-disulfide exchange reaction and the dehydroascorbate reductase activity. The dithiol-disulfide loop represented by this structure is unique since the cystine closer to the N-terminus has a highly acidic thiol pKa (3.8 as determined for the pig liver enzyme) that contributes to the protein's high S- nucleophilicity. Compared with the microbial enzyme, the mammalian thioltransferases (glutaredoxins) are extended at both N and C termini by 10-12 amino acid residues, including a second pair of cysteines toward the C-terminus with no known special function. Yeast thioltransferase is more like mammalian enzymes in length (106 amino acids) but more like E. coli glutaredoxin in being unblocked at the N-terminus and having only one set of cysteines; that is, at the active center. The three mammalian enzymes, for which sequences are available, are blocked at the N-terminus by an acetyl group linked to alanine with no known special function other than possibly to impart greater cellular turnover stability. A report of carbohydrate (8.6%) content in rat liver thioltransferase has not been verified by more sensitive methods of carbohydrate analysis, nor has carbohydrate been identified in samples of purified glutaredoxin from any source. Thiol transferase and glutaredoxin are two names for the same protein based on similarity of amino acid sequence, immunochemical cross-reactivity, and other enzyme properties. The inability of thioltransferase from some mammalian sources to act as an electron carrier in ribonucleotide reductase systems, whether homologous or heterologous in origin, remains to be explained in future studies.
Collapse
Affiliation(s)
- W W Wells
- Department of Biochemistry, Michigan State University, East Lansing
| | | | | | | |
Collapse
|
14
|
Fu RY, Bongers RS, van Swam II, Chen J, Molenaar D, Kleerebezem M, Hugenholtz J, Li Y. Introducing glutathione biosynthetic capability into Lactococcus lactis subsp. cremoris NZ9000 improves the oxidative-stress resistance of the host. Metab Eng 2006; 8:662-71. [PMID: 16962352 DOI: 10.1016/j.ymben.2006.07.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2006] [Revised: 06/28/2006] [Accepted: 07/25/2006] [Indexed: 01/23/2023]
Abstract
This study describes how a metabolic engineering approach can be used to improve bacterial stress resistance. Some Lactococcus lactis strains are capable of taking up glutathione, and the imported glutathione protects this organism against H(2)O(2)-induced oxidative stress. L. lactis subsp. cremoris NZ9000, a model organism of this species that is widely used in the study of metabolic engineering, can neither synthesize nor take up glutathione. The study described here aimed to improve the oxidative-stress resistance of strain NZ9000 by introducing a glutathione biosynthetic capability. We show that the glutathione produced by strain NZ9000 conferred stronger resistance on the host following exposure to H(2)O(2) (150 mM) and a superoxide generator, menadione (30 microM). To explore whether glutathione can complement the existing oxidative-stress defense systems, we constructed a superoxide dismutase deficient mutant of strain NZ9000, designated as NZ4504, which is more sensitive to oxidative stress, and introduced the glutathione biosynthetic capability into this strain. Glutathione produced by strain NZ4504(pNZ3203) significantly shortens the lag phase of the host when grown aerobically, especially in the presence of menadione. In addition, cells of NZ4504(pNZ3203) capable of producing glutathione restored the resistance of the host to H(2)O(2)-induced oxidative stress, back to the wild-type level. We conclude that the resistance of L. lactis subsp. cremoris NZ9000 to oxidative stress can be increased in engineered cells with glutathione producing capability.
Collapse
Affiliation(s)
- Rui-Yan Fu
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Southern Yangtze University, Wuxi 214036, People's Republic of China
| | | | | | | | | | | | | | | |
Collapse
|
15
|
Kranner I, Cram WJ, Zorn M, Wornik S, Yoshimura I, Stabentheiner E, Pfeifhofer HW. Antioxidants and photoprotection in a lichen as compared with its isolated symbiotic partners. Proc Natl Acad Sci U S A 2005; 102:3141-6. [PMID: 15710882 PMCID: PMC549463 DOI: 10.1073/pnas.0407716102] [Citation(s) in RCA: 133] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2004] [Accepted: 01/13/2005] [Indexed: 11/18/2022] Open
Abstract
Extreme desiccation and irradiation increase the formation of reactive oxygen species in organisms. Lichens are highly resistant to potential damage, but it is not known whether biochemical interaction between their fungal and algal partners is involved in conferring stress tolerance. Here, we show that antioxidant and photoprotective mechanisms in the lichen Cladonia vulcani are more effective by orders of magnitude than those of its isolated partners. When alone, both alga and fungus suffer oxidative damage during desiccation, but in the lichen, each appears to induce up-regulation of protective systems in the other. Without the fungal contact, the alga tolerates only very dim light and its photoprotective system is only partially effective; without the alga, the glutathione-based antioxidant system of the fungus is slow and ineffective. In the lichen, this mutually enhanced resistance to oxidative stress and, in particular, its desiccation tolerance are essential for life above ground. This lifestyle, in turn, increases the chance of dispersal of reproductive propagules and ensures their joint evolutionary success.
Collapse
Affiliation(s)
- Ilse Kranner
- Institute of Plant Sciences, Karl-Franzens University of Graz, Schubertstrasse 51, A-8010 Graz, Austria.
| | | | | | | | | | | | | |
Collapse
|
16
|
Alirezaei M, Marin P, Nairn AC, Glowinski J, Prémont J. Inhibition of protein synthesis in cortical neurons during exposure to hydrogen peroxide. J Neurochem 2001; 76:1080-8. [PMID: 11181828 DOI: 10.1046/j.1471-4159.2001.00105.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Transient cerebral ischemia, which is accompanied by a sustained release of glutamate and zinc, as well as H(2)O(2) formation during the reperfusion period, strongly depresses protein synthesis. We have previously demonstrated that the glutamate-induced increase in cytosolic Ca(2+) is likely responsible for blockade of the elongation step of protein synthesis, whereas Zn(2+) preferentially inhibits the initiation step. In this study, we provide evidence indicating that H(2)O(2) and thapsigargin mobilized a common intracellular Ca(2+) pool. H(2)O(2) treatment stimulated a slow increase in intracellular Ca(2+), and precluded the effect of thapsigargin on Ca(2+) mobilization. H(2)O(2) stimulated the phosphorylation of both eIF-2alpha and eEF-2, in a time- and dose-dependent manner, suggesting that both the blockade of the elongation and of the initiation step are responsible for the H(2)O(2)-induced inhibition of protein synthesis. However, kinetic data indicated that, at least during the first 15 min of H(2)O(2) treatment, the inhibition of protein synthesis resulted mainly from the phosphorylation of eEF-2. In conclusion, H(2)O(2) inhibits protein translation in cortical neurons by a process that involves the phosphorylation of both eIF-2alpha and eEF-2 and the relative contribution of these two events depends on the duration of H(2)O(2) treatment.
Collapse
Affiliation(s)
- M Alirezaei
- Chaire de Neuropharmacologie, INSERM U114, Collège de France, Paris, France
| | | | | | | | | |
Collapse
|
17
|
Latour I, De Ros E, Denef JF, Buc Calderon P. Protein S-thiolation can mediate the inhibition of protein synthesis induced by tert-butyl hydroperoxide in isolated rat hepatocytes. Toxicol Appl Pharmacol 1999; 160:1-9. [PMID: 10502497 DOI: 10.1006/taap.1999.8757] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A rapid inhibition of protein synthesis is observed when isolated rat hepatocytes are incubated in the presence of 0.25-0.5 mM of tert-butyl hydroperoxide (tBOOH). Such an inhibition occurs in the absence of a cytolytic effect by tBOOH. Iron chelators (o-phenanthroline and desferrioxiamine), protected against oxidative cell death, but they did not modify the inhibition of protein synthesis caused by tBOOH (0.5 mM), suggesting that free radicals are less implicated in such an impairment. Electron micrographs of hepatocytes under oxidative stress show disaggregation of polyribosomes but not oxidative alterations, such as blebs or mitochondrial swelling. Protein synthesis inhibition is accompanied by a decrease in reduced glutathione (GSH) and an increase in glutathione disulfide (GSSG) and the level of protein S-thiolation (protein mixed disulfides formation). Such an increase of GSSG appears as a critical event since diethylmaleate (DEM) at 0.2 mM reduced GSH content by more than 50% but did not affect either GSSG content or protein synthesis. The addition of exogenous GSH and N-acetylcysteine (NAC) to tBOOH-treated hepatocytes significantly reduced the formation of protein mixed disulfides and restored the depressed protein synthesis either completely or partially. We suggest that S-thiolation of some key proteins may be involved in protein synthesis inhibition by tBOOH.
Collapse
Affiliation(s)
- I Latour
- Métabolisme, Université Catholique de Louvain, Bruxelles, 1200, Belgium
| | | | | | | |
Collapse
|
18
|
Huang RP, Peng A, Hossain MZ, Fan Y, Jagdale A, Boynton AL. Tumor promotion by hydrogen peroxide in rat liver epithelial cells. Carcinogenesis 1999; 20:485-92. [PMID: 10190566 DOI: 10.1093/carcin/20.3.485] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Reactive oxygen species, including H2O2, play an important role in the tumor promotion process. Using an in vitro model of tumor promotion involving the rat liver epithelial oval cell line T51B, the tumor promoting activity of H2O2 in N-methyl-N'-nitro-N-nitrosoguanidine-initiated cells was studied. In this assay system, the promoting effect of H2O2 is evidenced by the formation of colonies in soft agar, appearance of foci in monolayer culture, disruption of gap junction communication (GJC) in foci areas and growth at higher saturation densities. H2O2 preferentially induced the expression of c-fos, c-jun, c-myc and egr-1, while JunB and JunD levels remained almost unchanged. H2O2 also induced hyperphosphorylation of Cx43 and disruption of GJC. The effects of H2O2 on tumor promotion, induction of immediate early (IE) genes and disruption of GJC are blocked by antioxidants. These results suggest that H2O2 acts as a tumor promoter in rat liver non-neoplastic epithelial cells and that the induction of IE genes and disruption of GJC are two possible targets of H2O2 during the tumor promotion process.
Collapse
Affiliation(s)
- R P Huang
- Molecular Medicine, Northwest Hospital, Seattle, WA 98125, USA.
| | | | | | | | | | | |
Collapse
|
19
|
Krishnamoorthy T, Sreedhara A, Rao CP, Ramaiah KV. Reducing agents mitigate protein synthesis inhibition mediated by vanadate and vanadyl compounds in reticulocyte lysates. Arch Biochem Biophys 1998; 349:122-8. [PMID: 9439590 DOI: 10.1006/abbi.1997.0394] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Recently, we synthesized and characterized vanadyl saccharides to evaluate the effects of various vanadate and vanadyl complexes, which differ in their oxidation states on various biomacromolecules and cellular activities (1, 2). Here, we report that both vanadate (+V oxidation state) and different vanadyl species (+IV oxidation state) such as vanadyl D-glucose, vanadyl diascorbate, and vanadyl sulfate, impair the formation of polysomes and inhibit the initiation of protein synthesis in hemin-supplemented rabbit reticulocyte lysates. Vanadate inhibits protein synthesis more severely than vanadyl species and is consistent with the idea that vanadate is reduced to vanadyl state intracellularly. The inhibition of protein synthesis caused by low concentrations (10-20 microM) of vanadate and vanadyl species is effectively mitigated by reducing agents such as dithiothreitol, reduced glutathione (GSH), or reduced pyridine dinucleotide. A significant decrease in the protein synthesis inhibition in vanadate-treated lysates by GSH suggests that the mechanism of protein synthesis inhibition by vanadate is different than the action of other oxidants such as heavy metal ions and oxidized glutathione. This suggestion is also consistent with the findings that vanadium compounds do not stimulate phosphorylation of the alpha (alpha) subunit of initiation factor 2 (eIF2) or decrease the guanine nucleotide exchange activity of eIF2B, which is required to exchange GDP for GTP in eIF2.GDP binary complex. The reduction of vanadate to vanadyl state and the subsequent complex formation of vanadyl species with the endogenous reducing compounds or with the -SH groups of certain proteins may be the cause for protein synthesis inhibition in lysates.
Collapse
Affiliation(s)
- T Krishnamoorthy
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, India.
| | | | | | | |
Collapse
|
20
|
Kang YJ, Feng Y, Hatcher EL. Glutathione stimulates A549 cell proliferation in glutamine-deficient culture: the effect of glutamate supplementation. J Cell Physiol 1994; 161:589-96. [PMID: 7962140 DOI: 10.1002/jcp.1041610323] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Extracellular glutathione (GSH) is degraded by an external cell-surface enzyme, gamma-glutamyltranspeptidase (gamma-GT). The products are transported into cells to participate in important cellular processes. In the present study, we tested the hypothesis that extracellular GSH is a source of glutamic acid for cells that express gamma-GT. Under a glutamine-deficient culture condition, the extracellular GSH-supplemented glutamic acid would enhance intracellular glutamine synthesis, thereby stimulating cell proliferation. Human lung carcinoma A549 cells were cultured in glutamine-deficient Dulbecco's modified Eagle medium, and they did not proliferate unless glutamine was supplemented. Extracellular GSH, however, provoked a partial proliferation. The GSH effect correlated with a high level of gamma-GT activity and an increased intracellular level of glutamic acid. A constituent amino acid of GSH, glutamic acid but not cysteine, produced the same growth-stimulatory effect as GSH. Furthermore, neither oxothiazolidine-4-carboxylate (OTC), a cellular cysteine-delivery compound, nor cysteinylglycine, a dipeptide released from the gamma-GT reaction, stimulated cell proliferation. Moreover, buthionine sulfoximine (BSO), a selective inhibitor of gamma-glutamylcysteine synthetase, enhanced the GSH growth stimulatory effect, suggesting that increased cellular GSH synthesis does not correlate with cell growth stimulation. The results obtained demonstrated that glutamine is required for A549 cell proliferation and exogenous GSH partially substitutes for the growth stimulatory action of glutamine. It also suggests that the glutamic acid rather than the cysteine released from the GSH is responsible for the cell proliferation.
Collapse
Affiliation(s)
- Y J Kang
- Department of Pharmacology and Toxicology, University of North Dakota School of Medicine, Grand Forks, 58202-9037
| | | | | |
Collapse
|
21
|
Ravichandran V, Seres T, Moriguchi T, Thomas J, Johnston R. S-thiolation of glyceraldehyde-3-phosphate dehydrogenase induced by the phagocytosis-associated respiratory burst in blood monocytes. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)31491-6] [Citation(s) in RCA: 115] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
|
22
|
Ishikawa T, Ali-Osman F. Glutathione-associated cis-diamminedichloroplatinum(II) metabolism and ATP-dependent efflux from leukemia cells. Molecular characterization of glutathione-platinum complex and its biological significance. J Biol Chem 1993. [DOI: 10.1016/s0021-9258(20)80702-9] [Citation(s) in RCA: 182] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
23
|
Kranner I, Grill D. Content of low-molecular-weight thiols during the imbibition of Pea seeds. PHYSIOLOGIA PLANTARUM 1993; 88:557-562. [PMID: 28741765 DOI: 10.1111/j.1399-3054.1993.tb01371.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
The metabolism of low-molecular-weight thiols was investigated in seeds of Pisum sativum L. cv. Kleine Rheinländerin during imbibition in water for 14 h. The amount of oxidized glutathione (GSSG) decreased from 319 nmol (g dry weight)-1 in dry seeds to 38 nmol (g dry weight)-1 within the first 14 h of imbibition. The decrease may have been due to the reduction of GSSG to reduced glutathione (GSH), catalyzed by the enzyme glutathione reductase (GR; EC 1.6.4.2). The enzyme activity was high in dry seeds [25 nkat (g dry weight)-1 ] and decreased to 20 nkat (g dry weight)-1 within 14 h of imbibition. The activity of glucose-6-phosphate dehydrogenase (EC 1.1.1.49) decreased from 100 nkat (g dry weight)-1 in dry seeds to 67 nkat (g dry weight)-1 after 14 h of imbibition. Within 14 h the amount of γ-glutamyl-cysteine (γ-GC) decreased from 135 to 38 nmol (g dry weight)-1 , whereas the cysteine content rose from 81 nmol (g dry weight)-1 in dry seeds to a maximum of 170 nmol (g dry weight)-1 after 12 h of imbibition, which may be due to the degradation of γ-GC into cysteine.
Collapse
Affiliation(s)
- Ilse Kranner
- Inst. of Plant Physiology, Univ. Graz, Schubertstr. 51, A-8010 Graz, Austria
| | - Dieter Grill
- Inst. of Plant Physiology, Univ. Graz, Schubertstr. 51, A-8010 Graz, Austria
| |
Collapse
|
24
|
Yilla M, Doyle D, Sawyer JT. Early disulfide bond formation prevents heterotypic aggregation of membrane proteins in a cell-free translation system. J Cell Biol 1992; 118:245-52. [PMID: 1352780 PMCID: PMC2290040 DOI: 10.1083/jcb.118.2.245] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We previously demonstrated that a heterotypic complex of the two rat asialoglycoprotein receptor subunits was assembled during cell-free translation (Sawyer, J. T., and D. Doyle. 1990. Proc. Natl. Acad. Sci. USA. 87:4854-4858). We have characterized this system further by analyzing polypeptide interactions under both reducing and oxidizing translation conditions. This report shows that the complex represents a heterogeneous interaction between reduced membrane proteins rather than a specific oligomeric structure. In the reduced state membrane proteins interact in this system to form aggregates of diverse size and composition. The aggregated nascent polypeptides interact with the immunoglobulin heavy chain binding protein but this protein is not an integral component of the aggregate. Aggregation occurs via the exoplasmic domain, rather than the transmembrane domain, and the folding of this domain by the formation of intramolecular disulfides, prevents the interaction from occurring. Additionally, the folded molecules containing intramolecular disulfides lack high affinity binding activity and thus appear to resemble the earliest folding intermediates seen in vivo (Olson, J. T., and M. D. Lane. 198. FASEB (Fed. Am. Soc. Exp. Biol.) J. 3:1618-1624). These results lead us to suggest that the formation of intramolecular disulfides during early biogenesis serves to prevent nonspecific associations between nascent polypeptides.
Collapse
Affiliation(s)
- M Yilla
- Department of Biological Sciences, State University of New York, Buffalo 14260
| | | | | |
Collapse
|
25
|
Kang YJ, Enger MD. Increased glutathione levels in quiescent, serum-stimulated NRK-49F cells are associated not with a response to growth factors but with nutrient repletion. J Cell Physiol 1991; 148:197-201. [PMID: 1679059 DOI: 10.1002/jcp.1041480203] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Treatment of quiescent cells with serum results concomitantly in an increase in cellular glutathione (GSH) content and growth stimulation. A possible association between the GSH increase and the growth response was examined by studying separately the effects of nutrients and growth factors on the levels of cellular GSH and proliferation of quiescent NRK-49F cells. The addition of fresh medium with 10% calf serum was found to result in both a twofold increase in cellular GSH and growth stimulation (DNA synthesis and cell proliferation). 10% calf serum alone, without fresh medium, stimulated cell growth but failed to cause a comparable increase in cellular GSH. The addition of fresh medium without 10% serum, and of 0.5 mM cysteine and glutamate, resulted in both instances in a marked increase in cellular GSH, but failed to stimulate cell growth. EGF, in contrast, induced a complete mitogenic response but did not increase cellular GSH. Finally, pretreatment with L-buthionine-(S,R)-sulfoximine (BSO), a specific inhibitor of GSH synthesis, decreased cellular GSH and inhibited EGF-induced DNA synthesis, but these two responses do not, in their dose dependency, correlate. The results obtained thus show that the increase in cellular GSH that occurs in quiescent, serum-stimulated NRK-49F cells is a result of nutrient repletion rather than mitogenic stimulation, and increased GSH levels do not necessarily precede DNA synthesis and mitosis.
Collapse
Affiliation(s)
- Y J Kang
- Department of Zoology and Genetics, Iowa State University, Ames 50011
| | | |
Collapse
|
26
|
Matts R, Schatz J, Hurst R, Kagen R. Toxic heavy metal ions activate the heme-regulated eukaryotic initiation factor-2 alpha kinase by inhibiting the capacity of hemin-supplemented reticulocyte lysates to reduce disulfide bonds. J Biol Chem 1991. [DOI: 10.1016/s0021-9258(18)98955-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
27
|
Dhindsa RS. Drought Stress, Enzymes of Glutathione Metabolism, Oxidation Injury, and Protein Synthesis in Tortula ruralis. PLANT PHYSIOLOGY 1991; 95:648-51. [PMID: 16668032 PMCID: PMC1077581 DOI: 10.1104/pp.95.2.648] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
The activities of glutathione reductase (EC 1.6.4.2), glutathione peroxidase (EC 1.11.1.9), and glutathione S-transferase (EC 2.5.1.18) were found to increase during slow drying or during rehydration following rapid drying of the drought-tolerant moss Tortula ruralis. Little change was observed in the activity of malate deydrogenase (NAD(+) oxidoreductase, EC 1.1.1.37) during dehydration or subsequent rehydration. When the tissue was treated with cycloheximide, actinomycin D, or cordycepin, the increase in the activities of glutathione reductase and glutathione S-transferase was largely prevented while effect on glutathione peroxidase was much smaller. Concomitantly, oxidized glutathione (GSSG) as percentage of total glutathione increased. GSSG level was correlated positively with the levels of lipid peroxidation and solute leakage and negatively with the rate of protein synthesis. The results show that GSSG level is a good indicator of oxidation stress and provide support to the suggestion that GSSG mediates, at least in part, the drought stress-induced inhibition of protein synthesis.
Collapse
Affiliation(s)
- R S Dhindsa
- Department of Biology, McGill University, Montreal, Quebec H3A 1B1, Canada
| |
Collapse
|
28
|
Chen JJ, Pal JK, Petryshyn R, Kuo I, Yang JM, Throop MS, Gehrke L, London IM. Amino acid microsequencing of internal tryptic peptides of heme-regulated eukaryotic initiation factor 2 alpha subunit kinase: homology to protein kinases. Proc Natl Acad Sci U S A 1991; 88:315-9. [PMID: 1671169 PMCID: PMC50801 DOI: 10.1073/pnas.88.2.315] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
We have purified the heme-regulated eukaryotic initiation factor 2 alpha subunit (eIF-2 alpha) kinase (HRI) from rabbit reticulocytes for amino acid microsequencing. This kinase is a single 92-kDa polypeptide and migrates in perfect alignment with 32P-labeled HRI on SDS/PAGE. Its functions of binding ATP and of autophosphorylation and eIF-2 alpha phosphorylation are inhibited by hemin. The amino acid sequences of three tryptic peptides of HRI have been obtained. A search of the data base of the National Biomedical Research Foundation reveals that these amino acid sequences are unique and that two of these three sequences show homology to protein kinases. HRI peptide P-52 contains Asp-Phe-Gly, which is the most highly conserved short stretch of amino acids in catalytic domain VII of protein kinases. HRI peptide P-74 contains the conserved amino acid residues Asp-(Met)-Tyr-Ser-(Val)-Gly-Val found in catalytic domain IX of protein kinases [Hanks, S. K., Quinn, A. M. & Hunter, T. (1988) Science 241, 42-52]. These findings are consistent with the autokinase and eIF-2 alpha kinase activities of HRI. Synthetic HRI peptide P-74 is a very potent inhibitor of eIF-2 alpha phosphorylation by HRI. Since little is known about the function of conserved domain IX, P-74 peptide may be useful in elucidating the role of this domain of protein kinases.
Collapse
Affiliation(s)
- J J Chen
- Harvard-MIT Division of Health Sciences, Cambridge, MA 02139
| | | | | | | | | | | | | | | |
Collapse
|
29
|
Ayala A, Fabregat I, Machado A. Possible involvement of NADPH requirement in regulation of glucose-6-phosphate and 6-phosphogluconate dehydrogenase levels in rat liver. Mol Cell Biochem 1990; 95:107-15. [PMID: 2195319 DOI: 10.1007/bf00219968] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Previous studies examining regulation of synthesis of Glucose-6-Phosphate and 6-Phosphogluconate dehydrogenase in rat liver have focussed on the induction of these enzymes by different diets and some hormones. However, the precise mechanism regulating increases in the activities of these enzymes is unknown and the factors involved remain unidentified. Considering that many of these metabolic conditions occur simultaneously with the increase of some NADPH consuming pathway, in particular fatty acid synthesis, we suggest that the activities of Glucose-6-Phosphate and 6-Phosphogluconate dehydrogenase could be regulated through a mechanism involving changes in the NADPH requirement. Here, we have studied the effect of changes in the flux through different NADPH consuming pathways on the NADPH/NADP ratio and on Glucose-6-Phosphate and 6-Phosphogluconate levels. The results show that: i) an increase in consumption of NADPH, caused by activation of fatty acid synthesis or the detoxification system which consumes NADPH, is paralleled by an increase in levels of these enzymes; ii) when increase in consumption of NADPH is prevented, Glucose-6-Phosphate and 6-Phosphogluconate dehydrogenase levels do not change.
Collapse
Affiliation(s)
- A Ayala
- Departamento de Bioquimica, Bromatologia y Toxicologia, Facultad de Farmacia, Universidad de Sevilla, Spain
| | | | | |
Collapse
|
30
|
Atzori L, Dypbukt JM, Sundqvist K, Cotgreave I, Edman CC, Moldéus P, Grafström RC. Growth-associated modifications of low-molecular-weight thiols and protein sulfhydryls in human bronchial fibroblasts. J Cell Physiol 1990; 143:165-71. [PMID: 2318904 DOI: 10.1002/jcp.1041430123] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The thiol redox status of cultured human bronchial fibroblasts has been characterized at various growth conditions using thiol-reactive monobromobimane, with or without the combination of dithiotreitol, a strong reducing agent. This procedure has enabled measurement of the cellular content of reduced glutathione (GSH), total glutathione equivalents, cysteine, total cysteine equivalents, protein sulfhydryls, protein disulfides, and mixed disulfides. Passage of cells with trypsin perturbs the cellular thiol homeostasis and causes a 50% decrease in the GSH content, whereas the total cysteine content is subsequently increased severalfold during cell attachment. During subsequent culture, transient severalfold increased levels of GSH, protein-bound thiols, and protein disulfides are reached, whereas the total cysteine content gradually declines. These changes in the redox balance of both low-molecular-weight thiols and protein-bound thiols correlate with cell proliferation and mostly precede the major growth phase. When the onset of proliferation is inhibited by maintenance of cells in medium containing decreased amounts of serum, the GSH content remains significantly increased. Subsequent stimulation of growth by addition of serum results in decreased GSH levels at the onset of proliferation. In thiol-depleted medium, proliferation is also inhibited, whereas GSH levels are increased to a lesser extent than in complete medium. Exposure to buthionine sulfoximine inhibits growth, prevents GSH synthesis, and results in accumulation of total cysteine, protein-bound cysteine, and protein disulfides. For extracellular cystine, variable rates of cellular uptake correlate with the initial increase in the total cysteine content observed following subculture and with the GSH peak that precedes active proliferation. The results strongly suggest that specific fluctuations in the cellular redox balance of both free low-molecular-weight thiols and protein sulfhydryls are involved in growth regulation of normal human fibroblasts.
Collapse
Affiliation(s)
- L Atzori
- Department of Toxicology, Karolinska Institutet, Stockholm, Sweden
| | | | | | | | | | | | | |
Collapse
|
31
|
Evidence for the Association of the Heme-regulated eIF-2α Kinase with the 90-kDa Heat Shock Protein in Rabbit Reticulocyte Lysate in Situ. J Biol Chem 1989. [DOI: 10.1016/s0021-9258(19)84864-0] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
|
32
|
Hille A, Waheed A, von Figura K. The Ligand-binding Conformation of Mr 46,000 Mannose 6-phosphate-specific Receptor. J Biol Chem 1989. [DOI: 10.1016/s0021-9258(18)80019-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
|
33
|
Kass GE, Duddy SK, Orrenius S. Activation of hepatocyte protein kinase C by redox-cycling quinones. Biochem J 1989; 260:499-507. [PMID: 2764885 PMCID: PMC1138696 DOI: 10.1042/bj2600499] [Citation(s) in RCA: 122] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The effects of quinone-generated active oxygen species on rat hepatocyte protein kinase C were investigated. The specific activity of cytosolic protein kinase C was increased 2-3-fold in hepatocytes incubated with the redox-cycling quinones, menadione, duroquinone or 2,3-dimethoxy-1,4-naphthoquinone, without alterations in particulate protein kinase C specific activity or Ca2+- and lipid-independent kinase activities. Redox-cycling quinones did not stimulate translocation of protein kinase C; however, activated protein kinase C was redistributed from cytosol to the particulate fraction when quinone-treated hepatocytes were exposed to 12-O-tetradecanoylphorbol 13-acetate (TPA). Quinone treatment did not alter cytosolic phorbol 12,13-dibutyrate (PDBu) binding capacity, and the cytosol of both control and quinone-treated hepatocytes exhibited a Kd for PDBu binding of 2 nM. Quinone-mediated activation of cytosolic protein kinase C was reversed by incubation with 10 mM-beta-mercaptoethanol, dithiothreitol or GSH, at 4 degrees C for 24 h. Furthermore, protein kinase C specific activity in control cytosol incubated in air increased by over 100% within 3 h; this increase was reversed by thiol-reducing agents. Similarly, incubation of partially-purified rat brain protein kinase C in air, or with low concentrations of GSSG in the presence of GSH, resulted in a 2-2.5-fold increase in Ca2+- and lipid-dependent kinase activity. In contrast with the effects of the redox-cycling quinones, when hepatocytes were treated with the thiol agents N-ethylmaleimide (NEM), p-benzoquinone (pBQ) or p-chloromercuribenzoic acid (pCMB), the cytosolic Ca2+- and lipid-dependent kinase activity was significantly inhibited, but the particulate-associated protein kinase C activity was unaffected. The Ca2+- and lipid-independent kinase activity of both the cytosolic and particulate fractions was significantly stimulated by NEM, but was unaffected by pBQ and pCMB. These results show that hepatocyte cytosolic protein kinase C is activated to a high-Vmax form by quinone-generated active oxygen species, and this effect is due to a reduction-sensitive modification of the thiol/disulphide status of protein kinase C.
Collapse
Affiliation(s)
- G E Kass
- Department of Toxicology, Karolinska Institutet, Stockholm, Sweden
| | | | | |
Collapse
|
34
|
Burdon RH, Rice-Evans C. Free radicals and the regulation of mammalian cell proliferation. FREE RADICAL RESEARCH COMMUNICATIONS 1989; 6:345-58. [PMID: 2676744 DOI: 10.3109/10715768909087918] [Citation(s) in RCA: 141] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The question of whether free radicals or free radical-related species play a role in the modulation of mammalian cell proliferation is examined. Although a positive role for free radicals as specific components of mitogenic pathways is not apparent it is clear that certain free radical-derived species can have a significant modulatory influence on components of major growth signal transduction mechanisms. Free radical-derived species are also involved in the production of prostaglandins which themselves can modulate cell growth. Free radicals themselves appear to have a down regulatory effect on cell proliferation inasmuch as protection from oxidative stress enhances cell proliferation. On the other hand, in certain cases low levels of active oxygen species can enhance cell proliferation.
Collapse
Affiliation(s)
- R H Burdon
- Department of Bioscience and Biotechnology, University of Strathclyde, Glasgow, London
| | | |
Collapse
|
35
|
Kan B, London IM, Levin DH. Role of reversing factor in the inhibition of protein synthesis initiation by oxidized glutathione. J Biol Chem 1988. [DOI: 10.1016/s0021-9258(19)37637-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
36
|
Mick SJ, Abramson RD, Ray BK, Merrick WC, Thach RE, Hagedorn CH. Induction of eIF-4E phosphorylation by the addition of L-pyrroline-5-carboxylic acid to rabbit reticulocyte lysate. FEBS Lett 1988; 236:484-8. [PMID: 3410057 DOI: 10.1016/0014-5793(88)80082-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Addition of L-pyrroline-5-carboxylic acid to reticulocyte lysates inhibits protein synthesis and induced phosphoproteins of 25 and 14 kDa. The 25 kDa phosphoprotein had the same Mr and pI as phosphorylated eIF-4E. Incubation of lysates with L-pyrroline-5-carboxylic acid did not alter the crosslinking of eIF-4E to reovirus mRNA caps. These results suggest that modifications of the translational apparatus other than eIF-4E phosphorylation may mediate the inhibitory effect seen with L-pyrroline-5-carboxylic acid and/or that phosphorylation of eIF-4E may effect functions subsequent to its interaction with the mRNA cap such as protein-protein interactions with other cap-specific translation factors.
Collapse
Affiliation(s)
- S J Mick
- Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110
| | | | | | | | | | | |
Collapse
|
37
|
Dhindsa RS. Protein Synthesis during Rehydration of Rapidly Dried Tortula ruralis: Evidence for Oxidation Injury. PLANT PHYSIOLOGY 1987; 85:1094-8. [PMID: 16665810 PMCID: PMC1054400 DOI: 10.1104/pp.85.4.1094] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Rapidly dried Tortula ruralis, a drought-tolerant moss, is known to synthesize proteins on rehydration at a much lower rate than the slowly dried moss. The reasons for this low rate of protein synthesis are unclear. We have found that during rehydration of rapidly dried moss, there is a negative correlation between the rate of protein synthesis and the tissue levels of oxidized glutathione (GSSG) and lipid peroxidation. When rapidly dried moss, which is known to show extensive solute leakage, is rehydrated in the presence of 100 millimolar K(+), 5 millimolar Mg(2+), 1 millimolar ATP, and 1 millimolar GTP, either separately or together, there is no stimulation of protein synthesis. When it is hydrated in the presence of either 5 millimolar glucose-6-phosphate or 0.1 millimolar NADPH, protein synthesis is stimulated but the stimulation is transitory. A second addition of either of these two chemicals causes a second transient stimulation of protein synthesis. A transitory decrease in the rate of GSSG accumulation is observed during rehydration in the presence of glucose-6-phosphate or NADPH. Both glucose-6-phosphate and NADPH are known to reverse GSSG-induced inhibition of protein synthesis in rabbit reticulocyte lysate. Results of the present study suggest that the rate of protein synthesis during rehydration of rapidly dried moss is not limited by the availability of ions or energy sources. Since exogenously applied GSSG has been shown to inhibit in vivo and in vitro protein synthesis and since it is known to accumulate during rehydration of rapidly dried, but not slowly dried, moss, it is suggested that the low rate of protein synthesis during rehydration of the rapidly dried moss is, at least in part, due to endogenous GSSG.
Collapse
Affiliation(s)
- R S Dhindsa
- Center for Plant Molecular Biology, McGill University, Montreal, Quebec, H3A 1B1, Canada
| |
Collapse
|
38
|
Hurst R, Schatz JR, Matts RL. Inhibition of rabbit reticulocyte lysate protein synthesis by heavy metal ions involves the phosphorylation of the alpha-subunit of the eukaryotic initiation factor 2. J Biol Chem 1987. [DOI: 10.1016/s0021-9258(18)47679-x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
39
|
De Felici M, Dolci S, Siracusa G. Involvement of thiol-disulfide groups in the sensitivity of fully grown mouse oocytes to calcium-free medium. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 1987; 243:283-7. [PMID: 3655685 DOI: 10.1002/jez.1402430213] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The lethality caused by calcium-free medium (CFM) to fully grown mouse oocytes significantly decreases if a disulfide reducing agent (dithiothreitol, reduced glutathione, or L-cysteine) is added to the medium. In this condition, most of the surviving oocytes do not spontaneously resume meiosis. We also show that the sulfhydryl content of fully grown oocytes, estimated by monobromobimane labeling, rapidly decreases during culture in CFM. The hypothesis is discussed that lethality of oocytes cultured in CFM may be a consequence of an alteration of thiol-disulfide balance.
Collapse
Affiliation(s)
- M De Felici
- Department of Anatomy and Cell Biology, II University of Rome, Italy
| | | | | |
Collapse
|
40
|
Dhindsa RS. Glutathione Status and Protein Synthesis during Drought and Subsequent Rehydration in Tortula ruralis. PLANT PHYSIOLOGY 1987; 83:816-9. [PMID: 16665345 PMCID: PMC1056456 DOI: 10.1104/pp.83.4.816] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Glutathione status and its relationship to protein synthesis during water deficit and subsequent rehydration have been examined in the drought-tolerant moss, Tortula ruralis. During slow drying there is a small decrease in total glutathione but the percentage of oxidized glutathione (GSSG) increases. During rapid drying there is little change in total glutathione but a small increase in GSSG. On rehydration of slowly dried moss, GSSG rapidly declines to normal level. But when rapidly dried moss is rehydrated, there is an immediate, sharp increase in GSSG as a percentage of total glutathione. After 2 hours of rehydration GSSG starts declining and reaches a normal level in about 6 hours. When an increasing degree of steady state water deficit is imposed on the moss tissue with polyethylene glycol 6000, there is a progressive decrease in protein synthesis but an increase in oxidized glutathione. When 5 millimolar GSSG is supplied exogenously during rehydration of rapidly dried or slowly dried moss, protein synthesis is strongly inhibited. In vitro protein synthesis supported by moss mRNA is also inhibited by more than 85% by 150 micromolar GSSG. The role of glutathione status in water deficit-induced inhibition of protein synthesis is discussed.
Collapse
Affiliation(s)
- R S Dhindsa
- Center for Plant Molecular Biology, McGill University, Montreal, Quebec, H3A 1B1, Canada
| |
Collapse
|
41
|
London IM, Levin DH, Matts RL, Thomas NSB, Petryshyn R, Chen JJ. 12 Regulation of Protein Synthesis. CONTROL BY PHOSPHORYLATION PART B - SPECIFIC ENZYMES (II) BIOLOGICAL PROCESSES 1987. [DOI: 10.1016/s1874-6047(08)60263-2] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
|
42
|
Matts RL, London IM. The regulation of initiation of protein synthesis by phosphorylation of eIF-2(alpha) and the role of reversing factor in the recycling of eIF-2. J Biol Chem 1984. [DOI: 10.1016/s0021-9258(17)39785-5] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
43
|
|
44
|
Tabarés E, Martínez J, Martín E, Escribano JM. Proteins specified by African Swine Fever virus. IV. Glycoproteins and phosphoproteins. Arch Virol 1983; 77:167-80. [PMID: 6416226 DOI: 10.1007/bf01309265] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
African Swine Fever virus infected MS cells labeled with radioactive 14C-amino acids, 32Pi or [3H]-glucosamine were examined by high resolution sodium dodecylsulfate polyacrylamide gel electrophoresis and showed 43 infected cell polypeptides. Twenty-one of these proteins were present in the nuclear fraction of infected cells. At least 22 of the infected cell polypeptides induced antibodies during natural infections in swine. The pattern of infected cell polypeptides modified by incorporation of showed prosthetic groups that at least 8 polypeptides were phosphorylated and at least three specific viral glycoproteins (A, B and C) were detected by immunoprecipitation. The most highly glycosylated polypeptide corresponds to the structural viral protein VP51.
Collapse
|
45
|
Jackson RJ, Herbert P, Campbell EA, Hunt T. The roles of sugar phosphates and thiol-reducing systems in the control of reticulocyte protein synthesis. ACTA ACUST UNITED AC 1983; 131:313-24. [PMID: 6550533 DOI: 10.1111/j.1432-1033.1983.tb07264.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
46
|
Jackson RJ, Campbell EA, Herbert P, Hunt T. The preparation and properties of gel-filtered rabbit-reticulocyte lysate protein-synthesis systems. EUROPEAN JOURNAL OF BIOCHEMISTRY 1983; 131:289-301. [PMID: 6832153 DOI: 10.1111/j.1432-1033.1983.tb07262.x] [Citation(s) in RCA: 72] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
|
47
|
Johnson HM. Interferon and host defense systems. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1983; 162:105-19. [PMID: 6191529 DOI: 10.1007/978-1-4684-4481-0_11] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
|
48
|
Scheele G, Jacoby R. Conformational changes associated with proteolytic processing of presecretory proteins allow glutathione-catalyzed formation of native disulfide bonds. J Biol Chem 1982. [DOI: 10.1016/s0021-9258(18)33711-6] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
49
|
Almiş-Kanigür G, Kan B, Kospançali S, Bermek E. A translational inhibitor activated in rabbit reticulocyte lysates under high pO2. FEBS Lett 1982; 145:143-6. [PMID: 6290264 DOI: 10.1016/0014-5793(82)81223-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
An inhibitor of protein synthesis was activated under high oxygen partial pressure (pO2) in hemin-supplemented and glutathione disulfide-free lysates from rabbit reticulocytes. This inhibitor shared some common features with other translational inhibitors from rabbit reticulocytes; that is, hemin-controlled repressor, glutathione disulfide-activated inhibitor and high pressure-activated inhibitor. It caused biphasic kinetics of inhibition which could be potentiated by ATP. Its activation was prevented by cAMP or glucose 6-phosphate. The high pO2-inhibitor could be partially purified from post-ribosomal supernatant containing ribosomal salt wash by precipitation between 0-50% (NH4)2SO4-saturation, Sephadex G-100, and DEAE-cellulose chromatography.
Collapse
|
50
|
Millner P, Widger W, Abbott M, Cramer W, Dilley R. The effect of adenine nucleotides on inhibition of the thylakoid protein kinase by sulfhydryl-directed reagents. J Biol Chem 1982. [DOI: 10.1016/s0021-9258(19)68099-3] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
|