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Caillet C, Stofberg ML, Muleya V, Shonhai A, Zininga T. Host cell stress response as a predictor of COVID-19 infectivity and disease progression. Front Mol Biosci 2022; 9:938099. [PMID: 36032680 PMCID: PMC9411049 DOI: 10.3389/fmolb.2022.938099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 07/15/2022] [Indexed: 11/13/2022] Open
Abstract
The coronavirus disease (COVID-19) caused by a coronavirus identified in December 2019 has caused a global pandemic. COVID-19 was declared a pandemic in March 2020 and has led to more than 6.3 million deaths. The pandemic has disrupted world travel, economies, and lifestyles worldwide. Although vaccination has been an effective tool to reduce the severity and spread of the disease there is a need for more concerted approaches to fighting the disease. COVID-19 is characterised as a severe acute respiratory syndrome . The severity of the disease is associated with a battery of comorbidities such as cardiovascular diseases, cancer, chronic lung disease, and renal disease. These underlying diseases are associated with general cellular stress. Thus, COVID-19 exacerbates outcomes of the underlying conditions. Consequently, coronavirus infection and the various underlying conditions converge to present a combined strain on the cellular response. While the host response to the stress is primarily intended to be of benefit, the outcomes are occasionally unpredictable because the cellular stress response is a function of complex factors. This review discusses the role of the host stress response as a convergent point for COVID-19 and several non-communicable diseases. We further discuss the merits of targeting the host stress response to manage the clinical outcomes of COVID-19.
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Affiliation(s)
- Celine Caillet
- Department of Biochemistry, Stellenbosch University, Stellenbosch, South Africa
| | | | - Victor Muleya
- Department of Biochemistry, Midlands State University, Gweru, Zimbabwe
| | - Addmore Shonhai
- Department of Biochemistry and Microbiology, University of Venda, Thohoyandou, South Africa
| | - Tawanda Zininga
- Department of Biochemistry, Stellenbosch University, Stellenbosch, South Africa
- *Correspondence: Tawanda Zininga,
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Effect of Reactive Oxygen Species on the Endoplasmic Reticulum and Mitochondria during Intracellular Pathogen Infection of Mammalian Cells. Antioxidants (Basel) 2021; 10:antiox10060872. [PMID: 34071633 PMCID: PMC8229183 DOI: 10.3390/antiox10060872] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 05/24/2021] [Accepted: 05/24/2021] [Indexed: 02/06/2023] Open
Abstract
Oxidative stress, particularly reactive oxygen species (ROS), are important for innate immunity against pathogens. ROS directly attack pathogens, regulate and amplify immune signals, induce autophagy and activate inflammation. In addition, production of ROS by pathogens affects the endoplasmic reticulum (ER) and mitochondria, leading to cell death. However, it is unclear how ROS regulate host defense mechanisms. This review outlines the role of ROS during intracellular pathogen infection, mechanisms of ROS production and regulation of host defense mechanisms by ROS. Finally, the interaction between microbial pathogen-induced ROS and the ER and mitochondria is described.
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Abstract
PURPOSE OF REVIEW The present review provides an overview of recent findings on new members of the protein disulfide isomerase (PDI) family required for thrombosis. RECENT FINDINGS Twenty years ago PDI was shown to mediate platelet aggregation, and 10 years ago PDI was shown to support thrombosis in vivo. Subsequently, other members of this endoplasmic reticulum family of enzymes, ERp57 and ERp5, were demonstrated to support thrombosis. A fourth member, ERp72, was recently shown to be required for platelet accumulation and fibrin deposition in vivo. None of these enzymes can individually support these processes. Moreover, aggregation of platelets deficient in a specific PDI is only recovered by the PDI that is missing. This implies that each PDI has a distinct role in activation of the αIIbβ3 fibrinogen receptor and platelet aggregation. Free thiols can be labeled in both subunits of αIIbβ3, suggesting cysteine-based reactions are involved in relaying conformational changes from the cytoplasmic tails to the integrin headpiece of this integrin. SUMMARY Multiple members of the PDI family support platelet function, and hemostasis and thrombosis with distinct roles in these processes. The individual cysteine targets of each enzyme and how these enzymes are integrated into a network that supports hemostasis and thrombosis remain to be elucidated.
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Ozfiliz-Kilbas P, Sarikaya B, Obakan-Yerlikaya P, Coker-Gurkan A, Arisan ED, Temizci B, Palavan-Unsal N. Cyclin-dependent kinase inhibitors, roscovitine and purvalanol, induce apoptosis and autophagy related to unfolded protein response in HeLa cervical cancer cells. Mol Biol Rep 2018; 45:815-828. [PMID: 29978381 DOI: 10.1007/s11033-018-4222-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Accepted: 06/25/2018] [Indexed: 12/11/2022]
Abstract
Roscovitine (Rosc) and purvalanol (Pur) are competitive inhibitors of cyclin-dependent kinases (CDKs) by targeting their ATP-binding pockets. Both drugs are shown to be effective to decrease cell viability and dysregulate the ratio of pro- and anti-apoptotic Bcl-2 family members, which finally led to apoptotic cell death in different cancer cell lines in vitro. It was well established that Bcl-2 family members have distinct roles in the regulation of other cellular processes such as endoplasmic reticulum (ER) stress. The induction of ER stress has been shown to play critical role in cell death/survival decision via autophagy or apoptosis. In this study, our aim was to investigate the molecular targets of CDK inhibitors on ER stress mechanism related to distinct cell death types in time-dependent manner in HeLa cervical cancer cells. Our results showed that Rosc and Pur decreased the cell viability, cell growth and colony formation, induced ER stress-mediated autophagy or apoptosis in time-dependent manner. Thus, we conclude that exposure of cells to CDK inhibitors induces unfolded protein response and ER stress leading to autophagy and apoptosis processes in HeLa cervical cancer cells.
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Affiliation(s)
- Pelin Ozfiliz-Kilbas
- Department of Molecular Biology and Genetics, Istanbul Kultur University, Atakoy Campus, 34156, Istanbul, Turkey
| | - Bahar Sarikaya
- Department of Molecular Biology and Genetics, Istanbul Kultur University, Atakoy Campus, 34156, Istanbul, Turkey
| | - Pinar Obakan-Yerlikaya
- Department of Molecular Biology and Genetics, Istanbul Kultur University, Atakoy Campus, 34156, Istanbul, Turkey.
| | - Ajda Coker-Gurkan
- Department of Molecular Biology and Genetics, Istanbul Kultur University, Atakoy Campus, 34156, Istanbul, Turkey
| | - Elif Damla Arisan
- Department of Molecular Biology and Genetics, Istanbul Kultur University, Atakoy Campus, 34156, Istanbul, Turkey
| | - Benan Temizci
- Department of Molecular Biology and Genetics, Istanbul Kultur University, Atakoy Campus, 34156, Istanbul, Turkey
| | - Narcin Palavan-Unsal
- Department of Molecular Biology and Genetics, Istanbul Kultur University, Atakoy Campus, 34156, Istanbul, Turkey
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Abstract
INTRODUCTION The protein disulfide isomerase (PDI) family of thiol isomerases are intracellular enzymes known to catalyze the oxidation, reduction and isomerization of disulfide bonds during protein synthesis in the endoplasmic reticulum. PDI and related members of the thiol isomerase family are known to localize extracellularly where they possess various functions. Among these, the role of PDI in the initiation of thrombus formation is best characterized. PDI is secreted within seconds from activated platelets and endothelial cells at the site of vascular injury and accumulates in the developing platelet-fibrin thrombus. Inhibition of PDI by antibodies or small molecule inhibitors blocks thrombus formation. Efforts are underway to identify extracellular substrates of PDI that participate in the network pathways linking thiol isomerases to thrombus formation. ERp57, ERp5 and ERp72 also play a role in initiation of thrombus formation but their specific extracellular substrates are unknown. Areas covered: The following review gives an overview of biochemistry of vascular thiol isomerases followed by a detailed description of their role in thrombosis and its clinical implications. Expert commentary: The thiol isomerase system, by controlling the initiation of thrombus formation, provides the regulatory switch by which the normal vasculature is protected under physiologic conditions from thrombi generation.
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Affiliation(s)
- Anish Sharda
- a Division of Hemostasis and Thrombosis , Beth Israel Deaconess Medical Center, Harvard Medical School , Boston , MA USA
| | - Bruce Furie
- a Division of Hemostasis and Thrombosis , Beth Israel Deaconess Medical Center, Harvard Medical School , Boston , MA USA
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Ke B, Zhu N, Luo F, Xu Y, Fang X. Targeted inhibition of endoplasmic reticulum stress: New hope for renal fibrosis (Review). Mol Med Rep 2017. [PMID: 28627612 PMCID: PMC5562070 DOI: 10.3892/mmr.2017.6762] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Chronic kidney disease (CKD) has a very high mortality rate and remains a global health challenge. Inhibiting renal fibrosis is one of the most promising therapeutic strategies for CKD. Recent studies have indicated that endoplasmic reticulum stress (ERS) serves an active role in the development of acute and chronic kidney disease, especially with regards to renal fibrosis. In the current review, the authors summarize the latest understanding of the role of ERS during the onset of renal fibrosis. ERS promotes renal fibrosis through multiple signaling pathways, such as transforming growth factor-β, epithelial-mesenchymal transition and oxidative stress. In addition, ERS also causes podocyte damage, leading to increased proteinuria and the development of renal fibrosis in rat models. In conclusion, targeted inhibition of ERS may become a promising therapeutic strategy for renal fibrosis.
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Affiliation(s)
- Ben Ke
- Department of Nephrology, The Third Hospital of Nanchang, Nanchang, Jiangxi 330009, P.R. China
| | - Na Zhu
- Nanchang University School of Medicine, Nanchang, Jiangxi 330006, P.R. China
| | - Fuli Luo
- Department of Nephrology, Chinese Medicine Hospital in Jiangxi Province, Nanchang, Jiangxi 330006, P.R. China
| | - Yang Xu
- Department of Nephrology, Jiangxi Provincial People's Hospital, Nanchang, Jiangxi 330006, P.R. China
| | - Xiangdong Fang
- Department of Nephrology, The Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, P.R. China
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The disulfide isomerase ERp72 supports arterial thrombosis in mice. Blood 2017; 130:817-828. [PMID: 28576878 DOI: 10.1182/blood-2016-12-755587] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 05/30/2017] [Indexed: 01/01/2023] Open
Abstract
Several CGHC motif-containing disulfide isomerases support thrombosis. We here report that endoplasmic reticulum protein 72 (ERp72), with 3 CGHC redox-active sites (ao, a, and a'), supports thrombosis. We generated a new conditional knockout mouse model and found that Tie2-Cre/ERp72fl/fl mice with blood and endothelial cells lacking ERp72 had prolonged tail bleeding times and decreased platelet accumulation in laser-induced cremaster arteriole injury and FeCl3-induced mesenteric arterial injury. Fibrin deposition was decreased in the laser injury model. Both platelet and fibrin accumulation defects were fully rescued by infusion of recombinant ERp72 containing functional a and a' CGHC motifs (ERp72(oo-ss-ss)). Infusion of ERp72 containing inactivated a and a' CGHC motifs (ERp72(ss-oo-oo)) inhibited platelet accumulation and fibrin deposition in wild-type mice. Infusion of ERp72(oo-ss-ss) into β3-null mice increased fibrin deposition in the absence of platelets. ERp72-null platelets had defective aggregation, JON/A binding, P-selectin expression, and adenosine triphosphate (ATP) secretion. The aggregation and ATP secretion defects were fully rescued by ERp72(oo-ss-ss) but partially rescued by ERp72(ss-oo-ss) and ERp72(ss-ss-oo). Aggregation and ATP secretion of human platelets was potentiated by ERp72(oo-ss-ss) but inhibited by ERp72(ss-oo-ss) and ERp72(ss-ss-oo). These data suggest that both the a and a' active sites are required for platelet function. ERp72 bound poorly to β3-null mouse platelets, and the addition of ERp72(oo-ss-ss) to human platelets generated thiols in αIIbβ3, suggesting a direct interaction of ERp72 with αIIbβ3. Defective aggregation of ERp72-null platelets was recovered by ERp72, but not other thiol isomerases. In summary, ERp72 plays a critical role in platelet function and coagulation through the a and a' CGHC motifs.
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Moon J, Gorson J, Wright ME, Yee L, Khawaja S, Shin HY, Karma Y, Musunri RL, Yun M, Holford M. Characterization and Recombinant Expression of Terebrid Venom Peptide from Terebra guttata. Toxins (Basel) 2016; 8:toxins8030063. [PMID: 26950153 PMCID: PMC4810208 DOI: 10.3390/toxins8030063] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2016] [Revised: 02/23/2016] [Accepted: 02/23/2016] [Indexed: 01/26/2023] Open
Abstract
Venom peptides found in terebrid snails expand the toolbox of active compounds that can be applied to investigate cellular physiology and can be further developed as future therapeutics. However, unlike other predatory organisms, such as snakes, terebrids produce very small quantities of venom, making it difficult to obtain sufficient amounts for biochemical characterization. Here, we describe the first recombinant expression and characterization of terebrid peptide, teretoxin Tgu6.1, from Terebra guttata. Tgu6.1 is a novel forty-four amino acid teretoxin peptide with a VI/VII cysteine framework (C-C-CC-C-C) similar to O, M and I conotoxin superfamilies. A ligation-independent cloning strategy with an ompT protease deficient strain of E. coli was employed to recombinantly produce Tgu6.1. Thioredoxin was introduced in the plasmid to combat disulfide folding and solubility issues. Specifically Histidine-6 tag and Ni-NTA affinity chromatography were applied as a purification method, and enterokinase was used as a specific cleavage protease to effectively produce high yields of folded Tgu6.1 without extra residues to the primary sequence. The recombinantly-expressed Tgu6.1 peptide was bioactive, displaying a paralytic effect when injected into a Nereis virens polychaete bioassay. The recombinant strategy described to express Tgu6.1 can be applied to produce high yields of other disulfide-rich peptides.
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Affiliation(s)
- John Moon
- Hunter College, City University of New York, Belfer Research Center 413 E. 69th Street, New York, NY 10021, USA.
| | - Juliette Gorson
- Hunter College, City University of New York, Belfer Research Center 413 E. 69th Street, New York, NY 10021, USA.
- The Graduate Center, City University of New York, 365 Fifth Avenue, New York, NY 10016, USA.
| | - Mary Elizabeth Wright
- Hunter College, City University of New York, Belfer Research Center 413 E. 69th Street, New York, NY 10021, USA.
- The Graduate Center, City University of New York, 365 Fifth Avenue, New York, NY 10016, USA.
| | - Laurel Yee
- Hunter College, City University of New York, Belfer Research Center 413 E. 69th Street, New York, NY 10021, USA.
| | - Samer Khawaja
- Hunter College, City University of New York, Belfer Research Center 413 E. 69th Street, New York, NY 10021, USA.
| | - Hye Young Shin
- Hunter College, City University of New York, Belfer Research Center 413 E. 69th Street, New York, NY 10021, USA.
| | - Yasmine Karma
- Hunter College, City University of New York, Belfer Research Center 413 E. 69th Street, New York, NY 10021, USA.
| | | | - Michelle Yun
- Hunter College, City University of New York, Belfer Research Center 413 E. 69th Street, New York, NY 10021, USA.
| | - Mande Holford
- Hunter College, City University of New York, Belfer Research Center 413 E. 69th Street, New York, NY 10021, USA.
- The Graduate Center, City University of New York, 365 Fifth Avenue, New York, NY 10016, USA.
- The American Museum of Natural History, 79th Street at Central Park West, New York, NY 10026, USA.
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9
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Zeeshan HMA, Lee GH, Kim HR, Chae HJ. Endoplasmic Reticulum Stress and Associated ROS. Int J Mol Sci 2016; 17:327. [PMID: 26950115 PMCID: PMC4813189 DOI: 10.3390/ijms17030327] [Citation(s) in RCA: 567] [Impact Index Per Article: 70.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 01/21/2016] [Accepted: 02/24/2016] [Indexed: 02/07/2023] Open
Abstract
The endoplasmic reticulum (ER) is a fascinating network of tubules through which secretory and transmembrane proteins enter unfolded and exit as either folded or misfolded proteins, after which they are directed either toward other organelles or to degradation, respectively. The ER redox environment dictates the fate of entering proteins, and the level of redox signaling mediators modulates the level of reactive oxygen species (ROS). Accumulating evidence suggests the interrelation of ER stress and ROS with redox signaling mediators such as protein disulfide isomerase (PDI)-endoplasmic reticulum oxidoreductin (ERO)-1, glutathione (GSH)/glutathione disuphide (GSSG), NADPH oxidase 4 (Nox4), NADPH-P450 reductase (NPR), and calcium. Here, we reviewed persistent ER stress and protein misfolding-initiated ROS cascades and their significant roles in the pathogenesis of multiple human disorders, including neurodegenerative diseases, diabetes mellitus, atherosclerosis, inflammation, ischemia, and kidney and liver diseases.
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Affiliation(s)
- Hafiz Maher Ali Zeeshan
- Department of Pharmacology and New Drug Development Institute, School of Medicine, Chonbuk National University, Jeonju, Chonbuk 561-180, Korea.
| | - Geum Hwa Lee
- Department of Pharmacology and New Drug Development Institute, School of Medicine, Chonbuk National University, Jeonju, Chonbuk 561-180, Korea.
| | - Hyung-Ryong Kim
- Department of Dental Pharmacology and Wonkwang Biomaterial Implant Research Institute, School of Dentistry, Wonkwang University, Iksan, Chonbuk 570-749, Korea.
| | - Han-Jung Chae
- Department of Pharmacology and New Drug Development Institute, School of Medicine, Chonbuk National University, Jeonju, Chonbuk 561-180, Korea.
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10
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Yuen CYL, Matsumoto KO, Christopher DA. Variation in the Subcellular Localization and Protein Folding Activity among Arabidopsis thaliana Homologs of Protein Disulfide Isomerase. Biomolecules 2013; 3:848-69. [PMID: 24970193 PMCID: PMC4030966 DOI: 10.3390/biom3040848] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Revised: 09/27/2013] [Accepted: 10/12/2013] [Indexed: 12/18/2022] Open
Abstract
Protein disulfide isomerases (PDIs) catalyze the formation, breakage, and rearrangement of disulfide bonds to properly fold nascent polypeptides within the endoplasmic reticulum (ER). Classical animal and yeast PDIs possess two catalytic thioredoxin-like domains (a, a') and two non-catalytic domains (b, b'), in the order a-b-b'-a'. The model plant, Arabidopsis thaliana, encodes 12 PDI-like proteins, six of which possess the classical PDI domain arrangement (AtPDI1 through AtPDI6). Three additional AtPDIs (AtPDI9, AtPDI10, AtPDI11) possess two thioredoxin domains, but without intervening b-b' domains. C-terminal green fluorescent protein (GFP) fusions to each of the nine dual-thioredoxin PDI homologs localized predominantly to the ER lumen when transiently expressed in protoplasts. Additionally, expression of AtPDI9:GFP-KDEL and AtPDI10: GFP-KDDL was associated with the formation of ER bodies. AtPDI9, AtPDI10, and AtPDI11 mediated the oxidative folding of alkaline phosphatase when heterologously expressed in the Escherichia coli protein folding mutant, dsbA-. However, only three classical AtPDIs (AtPDI2, AtPDI5, AtPDI6) functionally complemented dsbA-. Interestingly, chemical inducers of the ER unfolded protein response were previously shown to upregulate most of the AtPDIs that complemented dsbA-. The results indicate that Arabidopsis PDIs differ in their localization and protein folding activities to fulfill distinct molecular functions in the ER.
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Affiliation(s)
- Christen Y L Yuen
- Department of Molecular Biosciences and Bioengineering, University of Hawaii at Manoa, Honolulu, HI 96822, USA.
| | - Kristie O Matsumoto
- Department of Molecular Biosciences and Bioengineering, University of Hawaii at Manoa, Honolulu, HI 96822, USA.
| | - David A Christopher
- Department of Molecular Biosciences and Bioengineering, University of Hawaii at Manoa, Honolulu, HI 96822, USA.
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11
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Bulleid NJ. Disulfide bond formation in the mammalian endoplasmic reticulum. Cold Spring Harb Perspect Biol 2012; 4:4/11/a013219. [PMID: 23125019 DOI: 10.1101/cshperspect.a013219] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The formation of disulfide bonds between cysteine residues occurs during the folding of many proteins that enter the secretory pathway. As the polypeptide chain collapses, cysteines brought into proximity can form covalent linkages during a process catalyzed by members of the protein disulfide isomerase family. There are multiple pathways in mammalian cells to ensure disulfides are introduced into proteins. Common requirements for this process include a disulfide exchange protein and a protein oxidase capable of forming disulfides de novo. In addition, any incorrect disulfides formed during the normal folding pathway are removed in a process involving disulfide exchange. The pathway for the reduction of disulfides remains poorly characterized. This work will cover the current knowledge in the field and discuss areas for future investigation.
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Affiliation(s)
- Neil J Bulleid
- Institute of Molecular, Cellular and Systems Biology, College of Medical Veterinary and Life Sciences, University of Glasgow, United Kingdom.
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12
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Abstract
Analysis of the human genome reveals that approximately a third of all open reading frames code for proteins that enter the endoplasmic reticulum (ER), demonstrating the importance of this organelle for global protein maturation. The path taken by a polypeptide through the secretory pathway starts with its translocation across or into the ER membrane. It then must fold and be modified correctly in the ER before being transported via the Golgi apparatus to the cell surface or another destination. Being physically segregated from the cytosol means that the ER lumen has a distinct folding environment. It contains much of the machinery for fulfilling the task of protein production, including complex pathways for folding, assembly, modification, quality control, and recycling. Importantly, the compartmentalization means that several modifications that do not occur in the cytosol, such as glycosylation and extensive disulfide bond formation, can occur to secreted proteins to enhance their stability before their exposure to the extracellular milieu. How these various machineries interact during the normal pathway of folding and protein secretion is the subject of this review.
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Affiliation(s)
- Ineke Braakman
- Cellular Protein Chemistry, Faculty of Science, Utrecht University, Utrecht, The Netherlands.
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13
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Pedone E, Limauro D, D’Ambrosio K, De Simone G, Bartolucci S. Multiple catalytically active thioredoxin folds: a winning strategy for many functions. Cell Mol Life Sci 2010; 67:3797-814. [PMID: 20625793 PMCID: PMC11115506 DOI: 10.1007/s00018-010-0449-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2010] [Revised: 06/23/2010] [Accepted: 06/28/2010] [Indexed: 10/19/2022]
Abstract
The Thioredoxin (Trx) fold is a versatile protein scaffold consisting of a four-stranded β-sheet surrounded by three α-helices. Various insertions are possible on this structural theme originating different proteins, which show a variety of functions and specificities. During evolution, the assembly of different Trx fold domains has been used many times to build new multi-domain proteins able to perform a large number of catalytic functions. To clarify the interaction mode of the different Trx domains within a multi-domain structure and how their combination can affect catalytic performances, in this review, we report on a structural and functional analysis of the most representative proteins containing more than one catalytically active Trx domain: the eukaryotic protein disulfide isomerases (PDIs), the thermophilic protein disulfide oxidoreductases (PDOs) and the hybrid peroxiredoxins (Prxs).
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Affiliation(s)
- Emilia Pedone
- Istituto di Biostrutture e Bioimmagini-CNR, via Mezzocannone 16, 80134 Naples, Italy
| | - Danila Limauro
- Dipartimento di Biologia Strutturale e Funzionale, Università degli Studi di Napoli “Federico II”, Complesso Universitario Monte S. Angelo, Via Cinthia, 80126 Naples, Italy
| | - Katia D’Ambrosio
- Istituto di Biostrutture e Bioimmagini-CNR, via Mezzocannone 16, 80134 Naples, Italy
| | - Giuseppina De Simone
- Istituto di Biostrutture e Bioimmagini-CNR, via Mezzocannone 16, 80134 Naples, Italy
| | - Simonetta Bartolucci
- Dipartimento di Biologia Strutturale e Funzionale, Università degli Studi di Napoli “Federico II”, Complesso Universitario Monte S. Angelo, Via Cinthia, 80126 Naples, Italy
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14
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Kozlov G, Määttänen P, Thomas DY, Gehring K. A structural overview of the PDI family of proteins. FEBS J 2010; 277:3924-36. [DOI: 10.1111/j.1742-4658.2010.07793.x] [Citation(s) in RCA: 186] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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15
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Structure of the Catalytic a0a Fragment of the Protein Disulfide Isomerase ERp72. J Mol Biol 2010; 401:618-25. [DOI: 10.1016/j.jmb.2010.06.045] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2010] [Revised: 06/19/2010] [Accepted: 06/22/2010] [Indexed: 11/21/2022]
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16
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Hatahet F, Ruddock LW. Protein disulfide isomerase: a critical evaluation of its function in disulfide bond formation. Antioxid Redox Signal 2009; 11:2807-50. [PMID: 19476414 DOI: 10.1089/ars.2009.2466] [Citation(s) in RCA: 496] [Impact Index Per Article: 33.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Disulfide bond formation is probably involved in the biogenesis of approximately one third of human proteins. A central player in this essential process is protein disulfide isomerase or PDI. PDI was the first protein-folding catalyst reported. However, despite more than four decades of study, we still do not understand much about its physiological mechanisms of action. This review examines the published literature with a critical eye. This review aims to (a) provide background on the chemistry of disulfide bond formation and rearrangement, including the concept of reduction potential, before examining the structure of PDI; (b) detail the thiol-disulfide exchange reactions that are catalyzed by PDI in vitro, including a critical examination of the assays used to determine them; (c) examine oxidation and reduction of PDI in vivo, including not only the role of ERo1 but also an extensive assessment of the role of glutathione, as well as other systems, such as peroxide, dehydroascorbate, and a discussion of vitamin K-based systems; (d) consider the in vivo reactions of PDI and the determination and implications of the redox state of PDI in vivo; and (e) discuss other human and yeast PDI-family members.
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Affiliation(s)
- Feras Hatahet
- Department of Biochemistry, University of Oulu , Oulu, Finland
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17
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Kozlov G, Määttänen P, Schrag JD, Hura GL, Gabrielli L, Cygler M, Thomas DY, Gehring K. Structure of the noncatalytic domains and global fold of the protein disulfide isomerase ERp72. Structure 2009; 17:651-9. [PMID: 19446521 DOI: 10.1016/j.str.2009.02.016] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2008] [Revised: 02/17/2009] [Accepted: 02/19/2009] [Indexed: 02/03/2023]
Abstract
Protein disulfide isomerases are a family of proteins that catalyze the oxidation and isomerization of disulfide bonds in newly synthesized proteins in the endoplasmic reticulum. The family includes general enzymes such as PDI that recognize unfolded proteins, and others that are selective for specific classes of proteins. Here, we report the X-ray crystal structure of central non-catalytic domains of a specific isomerase, ERp72 (also called CaBP2 and protein disulfide-isomerase A4) from Rattus norvegicus. The structure reveals strong similarity to ERp57, a PDI-family member that interacts with the lectin-like chaperones calnexin and calreticulin but, unexpectedly, ERp72 does not interact with calnexin as shown by isothermal titration calorimetry and nuclear magnetic resonance (NMR) spectroscopy. Small-angle X-ray scattering (SAXS) of ERp72 was used to develop models of the full-length protein using both rigid body refinement and ab initio simulated annealing of dummy atoms. The two methods show excellent agreement and define the relative positions of the five thioredoxin-like domains of ERp72 and potential substrate or chaperone binding sites.
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Affiliation(s)
- Guennadi Kozlov
- Department of Biochemistry, McGill University, 3655 Promenade Sir William Osler, Montréal, Québec, Canada
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18
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Forster ML, Mahn JJ, Tsai B. Generating an unfoldase from thioredoxin-like domains. J Biol Chem 2009; 284:13045-56. [PMID: 19289469 DOI: 10.1074/jbc.m808352200] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Protein-disulfide isomerase (PDI), an endoplasmic reticulum (ER)-resident protein, is primarily known as a catalyst of oxidative protein folding but also has a protein unfolding activity. We showed previously that PDI unfolds the cholera toxin A1 (CTA1) polypeptide to facilitate the ER-to-cytosol retrotranslocation of the toxin during intoxication. We now provide insight into the mechanism of this unfoldase activity. PDI includes two redox-active (a and a') and two redox-inactive (b and b') thioredoxin-like domains, a linker (x), and a C-terminal domain (c) arranged as abb'xa'c. Using recombinant PDI fragments, we show that binding of CTA1 by the continuous PDIbb'xa' fragment is necessary and sufficient to trigger unfolding. The specific linear arrangement of bb'xa' and the type a domain (a' versus a) C-terminal to bb'x are additional determinants of activity. These data suggest a general mechanism for the unfoldase activity of PDI: the concurrent and specific binding of bb'xa' to particular regions along the CTA1 molecule triggers its unfolding. Furthermore, we show the bb' domains of PDI are indispensable to the unfolding reaction, whereas the function of its a' domain can be substituted partially by the a' domain from ERp57 (abb'xa'c) or ERp72 (ca degrees abb'xa'), PDI-like proteins that do not unfold CTA1 normally. However, the bb' domains of PDI were insufficient to convert full-length ERp57 into an unfoldase because the a domain of ERp57 inhibited toxin binding. Thus, we propose that generating an unfoldase from thioredoxin-like domains requires the bb'(x) domains of PDI followed by an a' domain but not preceded by an inhibitory a domain.
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Affiliation(s)
- Michele L Forster
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
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19
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Appenzeller-Herzog C, Ellgaard L. The human PDI family: versatility packed into a single fold. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2007; 1783:535-48. [PMID: 18093543 DOI: 10.1016/j.bbamcr.2007.11.010] [Citation(s) in RCA: 300] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 09/18/2007] [Revised: 11/16/2007] [Accepted: 11/20/2007] [Indexed: 12/12/2022]
Abstract
The enzymes of the protein disulfide isomerase (PDI) family are thiol-disulfide oxidoreductases of the endoplasmic reticulum (ER). They contain a CXXC active-site sequence where the two cysteines catalyze the exchange of a disulfide bond with or within substrates. The primary function of the PDIs in promoting oxidative protein folding in the ER has been extended in recent years to include roles in other processes such as ER-associated degradation (ERAD), trafficking, calcium homeostasis, antigen presentation and virus entry. Some of these functions are performed by non-catalytic members of the family that lack the active-site cysteines. Regardless of their function, all human PDIs contain at least one domain of approximately 100 amino acid residues with structural homology to thioredoxin. As we learn more about the individual proteins of the family, a complex picture is emerging that emphasizes as much their differences as their similarities, and underlines the versatility of the thioredoxin fold. Here, we primarily explore the diversity of cellular functions described for the human PDIs.
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Affiliation(s)
- Christian Appenzeller-Herzog
- Department of Molecular Biology, Universitetsparken 13, University of Copenhagen, DK - 2100 Copenhagen Ø., Denmark
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20
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van Lith M, Karala AR, Bown D, Gatehouse JA, Ruddock LW, Saunders PTK, Benham AM. A developmentally regulated chaperone complex for the endoplasmic reticulum of male haploid germ cells. Mol Biol Cell 2007; 18:2795-804. [PMID: 17507649 PMCID: PMC1949379 DOI: 10.1091/mbc.e07-02-0147] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Glycoprotein folding is mediated by lectin-like chaperones and protein disulfide isomerases (PDIs) in the endoplasmic reticulum. Calnexin and the PDI homologue ERp57 work together to help fold nascent polypeptides with glycans located toward the N-terminus of a protein, whereas PDI and BiP may engage proteins that lack glycans or have sugars toward the C-terminus. In this study, we show that the PDI homologue PDILT is expressed exclusively in postmeiotic male germ cells, in contrast to the ubiquitous expression of many other PDI family members in the testis. PDILT is induced during puberty and represents the first example of a PDI family member under developmental control. We find that PDILT is not active as an oxido-reductase, but interacts with the model peptide Delta-somatostatin and nonnative bovine pancreatic trypsin inhibitor in vitro, indicative of chaperone activity. In vivo, PDILT forms a tissue-specific chaperone complex with the calnexin homologue calmegin. The identification of a redox-inactive chaperone partnership defines a new system of testis-specific protein folding with implications for male fertility.
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Affiliation(s)
- Marcel van Lith
- Department of Biological and Biomedical Sciences, University of Durham, Durham, DH1 3LE, United Kingdom
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21
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Maattanen P, Kozlov G, Gehring K, Thomas DY. ERp57 and PDI: multifunctional protein disulfide isomerases with similar domain architectures but differing substrate–partner associationsThis paper is one of a selection of papers published in this Special Issue, entitled CSBMCB — Membrane Proteins in Health and Disease. Biochem Cell Biol 2006; 84:881-9. [PMID: 17215875 DOI: 10.1139/o06-186] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Secretory proteins become folded and acquire stabilizing disulfide bonds in the endoplasmic reticulum (ER). Correct disulfide bond formation is a key step in ER quality control (ERQC). Proteins with incorrect disulfide bonds are recognized by the quality control machinery and are retrotranslocated into the cytosol where they are degraded by the proteasome. The mammalian ER contains 17 disulfide isomerases and at least one of them, ERp57, works in conjunction with the ER lectin-like chaperones calnexin and calreticulin. The targeting of ERp57 to calnexin–calreticulin is mediated by its noncatalytic b′ domain, and analogous domains in other disulfide isomerases likely determine their substrate and partner preferences. This review discusses some explanations for the multiplicity of disulfide isomerases and highlights structural differences in the b′ domains of PDI and ERp57 as an example of how noncatalytic domains define specialized roles in oxidative folding.
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Affiliation(s)
- P Maattanen
- Biochemistry Department, McGill University, 3655 Promenade Sir William Osler, Montréal, QC H3G 1Y6, Canada.
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22
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Görlach A, Klappa P, Kietzmann T. The endoplasmic reticulum: folding, calcium homeostasis, signaling, and redox control. Antioxid Redox Signal 2006; 8:1391-418. [PMID: 16986999 DOI: 10.1089/ars.2006.8.1391] [Citation(s) in RCA: 493] [Impact Index Per Article: 27.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The endoplasmic reticulum (ER) plays a major role in regulating synthesis, folding, and orderly transport of proteins. It is also essentially involved in various cellular signaling processes, primarily by its function as a dynamic Ca(2+) store. Compared to the cytosol, oxidizing conditions are found in the ER that allow oxidation of cysteine residues in nascent polypeptide chains to form intramolecular disulfide bonds. However, compounds and enzymes such as PDI that catalyze disulfide bonds become reduced and have to be reoxidized for further catalytic cycles. A number of enzymes, among them products of the ERO1 gene, appear to provide oxidizing equivalents, and oxygen appears to be the final oxidant in aerobic living organisms. Thus, protein oxidation in the ER is connected with generation of reactive oxygen species (ROS). Changes in the redox state and the presence of ROS also affect the Ca(2+) homeostasis by modulating the functionality of ER-based channels and buffering chaperones. In addition, a close relationship exists between oxidative stress and ER stress, which both may activate signaling events leading to a rebalance of folding capacity and folding demand or to cell death. Thus, redox homeostasis appears to be a prerequisite for proper functioning of the ER.
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Affiliation(s)
- Agnes Görlach
- Experimental Pediatric Cardiology, Department of Pediatric Cardiology and Congenital Heart Disease, German Heart Center Munich at the Technical University Munich, Munich, Germany
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23
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Abstract
Two pathways for the formation of biosynthetic protein disulfide bonds have been characterized in the endoplasmic reticulum (ER) of eukaryotes. In the major pathway, the membrane-associated flavoprotein Ero1 generates disulfide bonds for transfer to protein disulfide isomerase (PDI), which is responsible for directly introducing disulfide bonds into secretory proteins. In a minor fungal-specific protein oxidation pathway, the membrane-associated flavoprotein Erv2 can catalyze disulfide bond formation via the transfer of oxidizing equivalents to PDI. Genomic sequencing has revealed an abundance of enzymes sharing homology with Ero1, Erv2, or PDI. Herein the authors discuss the functional, mechanistic, and potential structural similarities between these homologs and the core enzymes of the characterized ER oxidation pathways. In addition they speculate about the possible differences between these enzymes that may explain why the cell contains multiple proteins dedicated to a single process. Finally, the eukaryotic ER protein oxidation and reduction pathways are compared to the corresponding prokaryotic periplasmic pathways, to highlight the functional, mechanistic, and structural similarities that exist between the pathways in these two kingdoms despite very low primary sequence homology between the protein and small molecule components.
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Affiliation(s)
- Carolyn S Sevier
- Department of Biology, Massachusetts Institute of Technology, Cambridge, 02139, USA
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24
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Abstract
An emerging concept is that disulfide bonds can act as a dynamic scaffold to present mature proteins in different conformational and functional states on the cell surface. Two examples are the conversion of the receptor, integrin alphaIIbbeta3, from a low affinity to a high affinity state, and the interaction of CD4 receptor with the HIV-1 envelope glycoprotein gp120 to promote virus-cell fusion. In both of these cases there is a remodeling of the protein disulfide bonding pattern. The formation and rearrangement of disulfide bonds is modulated by a family of enzymes known as the thiol isomerases, which include protein disulfide isomerase (PDI), ERp5, ERp57, and ERp72. While these enzymes were reported originally to be restricted in location to the endoplasmic reticulum, in some cells thiol isomerases are found on the cell surface. This may indicate a wider role for these enzymes in cell function. In platelets it has been shown that reagents that react with cell surface sulfhydryl groups are capable of blocking a number of functional responses, including integrin-mediated aggregation, adhesion, and granule secretion. Furthermore, the use of function blocking antibodies to either PDI or ERp5 causes inhibition of these functional responses. This review summarizes current knowledge of the extracellular regulation of disulfide exchange and the implications of this in the regulation of cell function.
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Affiliation(s)
- Peter A Jordan
- School of Animal and Microbial Sciences, University of Reading, Whiteknights, Reading, United Kingdom
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Alanen HI, Salo KEH, Pirneskoski A, Ruddock LW. pH dependence of the peptide thiol-disulfide oxidase activity of six members of the human protein disulfide isomerase family. Antioxid Redox Signal 2006; 8:283-91. [PMID: 16677074 DOI: 10.1089/ars.2006.8.283] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Protein folding in the endoplasmic reticulum is often associated with the formation of native disulfide bonds, a process which in vivo is one of the rate limiting steps of protein folding and which is facilitated by the enzyme protein disulfide isomerase (PDI). Higher eukaryotes have multiple members of the PDI family, for example, seventeen human PDIs have been reported to date. With multiple members of the same family being present, even within the same cell, the question arises as to what differential functions are they performing? To date there has been no systematic evaluation of the enzymological properties of the different members of the PDI-family. To address the question of whether different PDI family members have differing thioldisulfide chemistry, we have recombinantly expressed and purified six members of the family, PDI, PDIp, ERp57, ERp72, P5, and PDIr from a single organism, human. An examination of the pH-dependence and nature of the rate limiting step for the peptide thiol-disulfide oxidase activity of these enzymes reveals that, with the exception of PDIr, they are all remarkably similar. In the light of this data potential differential functions for these enzymes are discussed.
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Affiliation(s)
- H I Alanen
- Biocenter Oulu and Department of Biochemistry, University of Oulu, Oulu, Finland
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26
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Kimura T, Nishida A, Ohara N, Yamagishi D, Horibe T, Kikuchi M. Functional analysis of the CXXC motif using phage antibodies that cross-react with protein disulphide-isomerase family proteins. Biochem J 2005; 382:169-76. [PMID: 15137910 PMCID: PMC1133927 DOI: 10.1042/bj20040116] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2004] [Revised: 04/27/2004] [Accepted: 05/12/2004] [Indexed: 11/17/2022]
Abstract
Polyclonal antibodies that had been raised against particular PDI (protein disulphide-isomerase) family proteins did not cross-react with other PDI family proteins. To evade immune tolerance to the important self-motif Cys-Xaa-Xaa-Cys, which is present in PDI family proteins, we used the phage display library [established by Griffiths, Williams, Hartley, Tomlinson, Waterhouse, Crosby, Kontermann, Jones, Low, Allison et al. (1994) EMBO J. 13, 3245-3260] to isolate successfully the phage antibodies that can cross-react with human and bovine PDIs, human P5, human PDI-related protein and yeast PDI. By measuring the binding of scFv (single-chain antibody fragment of variable region) to synthetic peptides and to mutants of PDI family proteins in a surface plasmon resonance apparatus, we identified clones that recognized sequences containing the CGHC motif or the CGHCK sequence. By using the isolated phage antibodies, we demonstrated for the first time that a lysine residue following the CXXC motif significantly increases the isomerase activities of PDI family proteins. Moreover, we demonstrated that the affinity of isolated scFvs for mutant PDI family proteins is proportional to the isomerase activities of their active sites.
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Affiliation(s)
- Taiji Kimura
- Department of Bioscience and Technology, Faculty of Science and Engineering, Ritsumeikan University, 1-1-1 Noji-higashi, Kusatsu, Shiga 525-8577, Japan
| | - Ai Nishida
- Department of Bioscience and Technology, Faculty of Science and Engineering, Ritsumeikan University, 1-1-1 Noji-higashi, Kusatsu, Shiga 525-8577, Japan
| | - Nobutoshi Ohara
- Department of Bioscience and Technology, Faculty of Science and Engineering, Ritsumeikan University, 1-1-1 Noji-higashi, Kusatsu, Shiga 525-8577, Japan
| | - Daisuke Yamagishi
- Department of Bioscience and Technology, Faculty of Science and Engineering, Ritsumeikan University, 1-1-1 Noji-higashi, Kusatsu, Shiga 525-8577, Japan
| | - Tomohisa Horibe
- Department of Bioscience and Technology, Faculty of Science and Engineering, Ritsumeikan University, 1-1-1 Noji-higashi, Kusatsu, Shiga 525-8577, Japan
| | - Masakazu Kikuchi
- Department of Bioscience and Technology, Faculty of Science and Engineering, Ritsumeikan University, 1-1-1 Noji-higashi, Kusatsu, Shiga 525-8577, Japan
- To whom correspondence should be addressed (email )
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Lemaire SD, Miginiac-Maslow M. The thioredoxin superfamily in Chlamydomonas reinhardtii. PHOTOSYNTHESIS RESEARCH 2004; 82:203-20. [PMID: 16143836 DOI: 10.1007/s11120-004-1091-x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2003] [Accepted: 02/23/2004] [Indexed: 05/04/2023]
Abstract
The thioredoxin (TRX) superfamily includes redox proteins such as thioredoxins, glutaredoxins (GRXs) and protein disulfide isomerases (PDI). These proteins share a common structural motif named the thioredoxin fold. They are involved in disulfide oxido-reduction and/or isomerization. The sequencing of the Arabidopsisgenome revealed an unsuspected multiplicity of TRX and GRX genes compared to other organisms. The availability of full Chlamydomonasgenome sequence offers the opportunity to determine whether this multiplicity is specific to higher plant species or common to all photosynthetic eukaryotes. We have previously shown that the multiplicity is more limited in Chlamydomonas for TRX and GRX families. We extend here our analysis to the PDI family. This paper presents a comparative analysis of the TRX, GRX and PDI families present in Arabidopsis,Chlamydomonas and Synechocystis. The putative subcellular localization of each protein and its relative expression level, based on EST data, have been investigated. This analysis provides a large overview of the redox regulatory systems present in Chlamydomonas. The data are discussed in view of recent results suggesting a complex cross-talk between the TRX, GRX and PDI redox regulatory networks.
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Affiliation(s)
- Stéphane D Lemaire
- Institut de Biotechnologie des Plantes, Université Paris-Sud, UMR 8618 CNRS, Bâtiment 630, 91405, Orsay Cedex, France,
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