1
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Sies H, Mailloux RJ, Jakob U. Fundamentals of redox regulation in biology. Nat Rev Mol Cell Biol 2024; 25:701-719. [PMID: 38689066 DOI: 10.1038/s41580-024-00730-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/26/2024] [Indexed: 05/02/2024]
Abstract
Oxidation-reduction (redox) reactions are central to the existence of life. Reactive species of oxygen, nitrogen and sulfur mediate redox control of a wide range of essential cellular processes. Yet, excessive levels of oxidants are associated with ageing and many diseases, including cardiological and neurodegenerative diseases, and cancer. Hence, maintaining the fine-tuned steady-state balance of reactive species production and removal is essential. Here, we discuss new insights into the dynamic maintenance of redox homeostasis (that is, redox homeodynamics) and the principles underlying biological redox organization, termed the 'redox code'. We survey how redox changes result in stress responses by hormesis mechanisms, and how the lifelong cumulative exposure to environmental agents, termed the 'exposome', is communicated to cells through redox signals. Better understanding of the molecular and cellular basis of redox biology will guide novel redox medicine approaches aimed at preventing and treating diseases associated with disturbed redox regulation.
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Affiliation(s)
- Helmut Sies
- Institute for Biochemistry and Molecular Biology I, Faculty of Medicine, Heinrich Heine University Düsseldorf, Düsseldorf, Germany.
- Leibniz Research Institute for Environmental Medicine, Düsseldorf, Germany.
| | - Ryan J Mailloux
- School of Human Nutrition, Faculty of Agricultural and Environmental Science, McGill University, Sainte-Anne-de-Bellevue, Quebec, Canada.
| | - Ursula Jakob
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI, USA.
- Department of Biological Chemistry, University of Michigan, Ann Arbor, MI, USA.
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2
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Wang D, Wang W, Song M, Xie Y, Kuang W, Yang P. Regulation of protein phosphorylation by PTPN2 and its small-molecule inhibitors/degraders as a potential disease treatment strategy. Eur J Med Chem 2024; 277:116774. [PMID: 39178726 DOI: 10.1016/j.ejmech.2024.116774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2024] [Revised: 08/09/2024] [Accepted: 08/12/2024] [Indexed: 08/26/2024]
Abstract
Protein tyrosine phosphatase nonreceptor type 2 (PTPN2) is an enzyme that dephosphorylates proteins with tyrosine residues, thereby modulating relevant signaling pathways in vivo. PTPN2 acts as tumor suppressor or tumor promoter depending on the context. In some cancers, such as colorectal, and lung cancer, PTPN2 defects could impair the protein tyrosine kinase pathway, which is often over-activated in cancer cells, and inhibit tumor development and progression. However, PTPN2 can also suppress tumor immunity by regulating immune cells and cytokines. The structure, functions, and substrates of PTPN2 in various tumor cells were reviewed in this paper. And we summarized the research status of small molecule inhibitors and degraders of PTPN2. It also highlights the potential opportunities and challenges for developing PTPN2 inhibitors as anticancer drugs.
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Affiliation(s)
- Dawei Wang
- State Key Laboratory of Natural Medicines and Jiang Su Key Laboratory of Drug Design and Optimization, China Pharmaceutical University, Nanjing 210009, China; Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China
| | - Wenmu Wang
- State Key Laboratory of Natural Medicines and Jiang Su Key Laboratory of Drug Design and Optimization, China Pharmaceutical University, Nanjing 210009, China; Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China
| | - Mingge Song
- State Key Laboratory of Natural Medicines and Jiang Su Key Laboratory of Drug Design and Optimization, China Pharmaceutical University, Nanjing 210009, China; Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China
| | - Yishi Xie
- State Key Laboratory of Natural Medicines and Jiang Su Key Laboratory of Drug Design and Optimization, China Pharmaceutical University, Nanjing 210009, China; Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China
| | - Wenbin Kuang
- State Key Laboratory of Natural Medicines and Jiang Su Key Laboratory of Drug Design and Optimization, China Pharmaceutical University, Nanjing 210009, China; Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China.
| | - Peng Yang
- State Key Laboratory of Natural Medicines and Jiang Su Key Laboratory of Drug Design and Optimization, China Pharmaceutical University, Nanjing 210009, China; Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China; Institute of Innovative Drug Discovery and Development, China Pharmaceutical University, Nanjing 211198, China.
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3
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Saeed AA, Klureza MA, Hekstra DR. Mapping protein conformational landscapes from crystallographic drug fragment screens. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.29.605395. [PMID: 39131376 PMCID: PMC11312500 DOI: 10.1101/2024.07.29.605395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 08/13/2024]
Abstract
Proteins are dynamic macromolecules. Knowledge of a protein's thermally accessible conformations is critical to determining important transitions and designing therapeutics. Accessible conformations are highly constrained by a protein's structure such that concerted structural changes due to external perturbations likely track intrinsic conformational transitions. These transitions can be thought of as paths through a conformational landscape. Crystallographic drug fragment screens are high-throughput perturbation experiments, in which thousands of crystals of a drug target are soaked with small-molecule drug precursors (fragments) and examined for fragment binding, mapping potential drug binding sites on the target protein. Here, we describe an open-source Python package, COLAV (COnformational LAndscape Visualization), to infer conformational landscapes from such large-scale crystallographic perturbation studies. We apply COLAV to drug fragment screens of two medically important systems: protein tyrosine phosphatase 1B (PTP-1B), which regulates insulin signaling, and the SARS CoV-2 Main Protease (MPro). With enough fragment-bound structures, we find that such drug screens also enable detailed mapping of proteins' conformational landscapes.
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Affiliation(s)
- Ammaar A. Saeed
- Department of Molecular & Cellular Biology, Harvard University, Cambridge, MA 02138
| | - Margaret A. Klureza
- Department of Chemistry & Chemical Biology, Harvard University, Cambridge, MA 02138
| | - Doeke R. Hekstra
- Department of Molecular & Cellular Biology, Harvard University, Cambridge, MA 02138
- School of Engineering & Applied Sciences, Harvard University, Cambridge, MA 02138
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4
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Welsh CL, Madan LK. Protein Tyrosine Phosphatase regulation by Reactive Oxygen Species. Adv Cancer Res 2024; 162:45-74. [PMID: 39069369 DOI: 10.1016/bs.acr.2024.05.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/30/2024]
Abstract
Protein Tyrosine Phosphatases (PTPs) help to maintain the balance of protein phosphorylation signals that drive cell division, proliferation, and differentiation. These enzymes are also well-suited to redox-dependent signaling and oxidative stress response due to their cysteine-based catalytic mechanism, which requires a deprotonated thiol group at the active site. This review focuses on PTP structural characteristics, active site chemical properties, and vulnerability to change by reactive oxygen species (ROS). PTPs can be oxidized and inactivated by H2O2 through three non-exclusive mechanisms. These pathways are dependent on the coordinated actions of other H2O2-sensitive proteins, such as peroxidases like Peroxiredoxins (Prx) and Thioredoxins (Trx). PTPs undergo reversible oxidation by converting their active site cysteine from thiol to sulfenic acid. This sulfenic acid can then react with adjacent cysteines to form disulfide bonds or with nearby amides to form sulfenyl-amide linkages. Further oxidation of the sulfenic acid form to the sulfonic or sulfinic acid forms causes irreversible deactivation. Understanding the structural changes involved in both reversible and irreversible PTP oxidation can help with their chemical manipulation for therapeutic intervention. Nonetheless, more information remains unidentified than is presently known about the precise dynamics of proteins participating in oxidation events, as well as the specific oxidation states that can be targeted for PTPs. This review summarizes current information on PTP-specific oxidation patterns and explains how ROS-mediated signal transmission interacts with phosphorylation-based signaling machinery controlled by growth factor receptors and PTPs.
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Affiliation(s)
- Colin L Welsh
- Department of Cell and Molecular Pharmacology & Experimental Therapeutics, College of Medicine, Medical University of South Carolina, Charleston, SC, United States
| | - Lalima K Madan
- Department of Cell and Molecular Pharmacology & Experimental Therapeutics, College of Medicine, Medical University of South Carolina, Charleston, SC, United States; Hollings Cancer Center, Medical University of South Carolina, Charleston, SC, United States.
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5
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Arnér ESJ, Schmidt EE. Unresolved questions regarding cellular cysteine sources and their possible relationships to ferroptosis. Adv Cancer Res 2024; 162:1-44. [PMID: 39069366 DOI: 10.1016/bs.acr.2024.04.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/30/2024]
Abstract
Cysteine is required for synthesis of glutathione (GSH), coenzyme A, other sulfur-containing metabolites, and most proteins. In most cells, cysteine comes from extracellular disulfide sources including cystine, glutathione-disulfide, and peptides. The thioredoxin reductase-1 (TrxR1)- or glutathione-disulfide reductase (GSR)-driven enzymatic systems can fuel cystine reduction via thioredoxins, glutaredoxins, or other thioredoxin-fold proteins. Free cystine enters cells thorough the cystine-glutamate antiporter, xCT, but systemically, plasma glutathione-disulfide might predominate as a cystine source. Erastin, inhibiting both xCT and voltage-dependent anion channels, induces ferroptotic cell death, so named because this type of cell death is antagonized by iron-chelators. Many cancer cells seem to be predisposed to ferroptosis, which has been proposed as a targetable cancer liability. Ferroptosis is associated with lipid peroxidation and loss of either glutathione peroxidase-4 (GPX4) or ferroptosis suppressor protein-1 (FSP1), which each prevent accumulation of lipid peroxides. It has been suggested that an xCT inhibition-induced cellular cysteine-deficiency lowers GSH levels, starving GPX4 for reducing power and allowing membrane lipid peroxides to accumulate, thereby causing ferroptosis. Aspects of ferroptosis are however not fully understood and need to be further scrutinized, for example that neither disruption of GSH synthesis, loss of GSH, nor disruption of glutathione disulfide reductase (GSR), triggers ferroptosis in animal models. Here we reevaluate the relationships between Erastin, xCT, GPX4, cellular cysteine and GSH, RSL3 or ML162, and ferroptosis. We conclude that, whereas both Cys and ferroptosis are potential liabilities in cancer, their relationship to each other remains insufficiently understood.
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Affiliation(s)
- Elias S J Arnér
- Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden; Department of Selenoprotein Research and the National Tumor Biology Laboratory, National Institutes of Oncology, Budapest, Hungary
| | - Edward E Schmidt
- Laboratory of Redox Biology, University of Veterinary Medicine, Budapest, Hungary; Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, United States.
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6
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Chen L, Qian Z, Zheng Y, Zhang J, Sun J, Zhou C, Xiao H. Structural analysis of PTPN21 reveals a dominant-negative effect of the FERM domain on its phosphatase activity. SCIENCE ADVANCES 2024; 10:eadi7404. [PMID: 38416831 PMCID: PMC10901363 DOI: 10.1126/sciadv.adi7404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 01/24/2024] [Indexed: 03/01/2024]
Abstract
PTPN21 belongs to the four-point-one, ezrin, radixin, moesin (FERM) domain-containing protein tyrosine phosphatases (PTP) and plays important roles in cytoskeleton-associated cellular processes like cell adhesion, motility, and cargo transport. Because of the presence of a WPE loop instead of a WPD loop in the phosphatase domain, it is often considered to lack phosphatase activity. However, many of PTPN21's biological functions require its catalytic activity. To reconcile these findings, we have determined the structures of individual PTPN21 FERM, PTP domains, and a complex between FERM-PTP. Combined with biochemical analysis, we have found that PTPN21 PTP is weakly active and is autoinhibited by association with its FERM domain. Disruption of FERM-PTP interaction results in enhanced ERK activation. The oncogenic HPV18 E7 protein binds to PTP at the same location as PTPN21 FERM, indicating that it may act by displacing the FERM domain from PTP. Our results provide mechanistic insight into PTPN21 and benefit functional studies of PTPN21-mediated processes.
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Affiliation(s)
- Lu Chen
- Department of Pathology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310016, China
- School of Public Health, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Zijun Qian
- Department of Hematology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310016, China
| | - Yuyuan Zheng
- School of Public Health, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
- Department of Cell Biology, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Jie Zhang
- Department of Hematology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310016, China
| | - Jie Sun
- Department of Cell Biology, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Chun Zhou
- Department of Pathology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310016, China
- School of Public Health, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Haowen Xiao
- Department of Hematology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310016, China
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7
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Fransen M, Lismont C. Peroxisomal hydrogen peroxide signaling: A new chapter in intracellular communication research. Curr Opin Chem Biol 2024; 78:102426. [PMID: 38237354 DOI: 10.1016/j.cbpa.2024.102426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2023] [Revised: 01/03/2024] [Accepted: 01/03/2024] [Indexed: 02/09/2024]
Abstract
Hydrogen peroxide (H2O2), a natural metabolite commonly found in aerobic organisms, plays a crucial role in numerous cellular signaling processes. One of the key organelles involved in the cell's metabolism of H2O2 is the peroxisome. In this review, we first provide a concise overview of the current understanding of H2O2 as a molecular messenger in thiol redox signaling, along with the role of peroxisomes as guardians and modulators of cellular H2O2 balance. Next, we direct our focus toward the recently identified primary protein targets of H2O2 originating from peroxisomes, emphasizing their importance in unraveling the complex interplay between peroxisomal H2O2 and cell signaling. We specifically focus on three areas: signaling through peroxiredoxin redox relay complexes, calcium signaling, and phospho-signaling. Finally, we highlight key research directions that warrant further investigation to enhance our comprehension of the molecular and biochemical mechanisms linking alterations in peroxisomal H2O2 metabolism with disease.
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Affiliation(s)
- Marc Fransen
- Laboratory of Peroxisome Biology and Intracellular Signaling, Department of Cellular and Molecular Medicine, Katholieke Universiteit Leuven, Herestraat 49 Box 901, 3000 Leuven, Belgium.
| | - Celien Lismont
- Laboratory of Peroxisome Biology and Intracellular Signaling, Department of Cellular and Molecular Medicine, Katholieke Universiteit Leuven, Herestraat 49 Box 901, 3000 Leuven, Belgium
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8
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Lolicato F, Steringer JP, Saleppico R, Beyer D, Fernandez-Sobaberas J, Unger S, Klein S, Riegerová P, Wegehingel S, Müller HM, Schmitt XJ, Kaptan S, Freund C, Hof M, Šachl R, Chlanda P, Vattulainen I, Nickel W. Disulfide bridge-dependent dimerization triggers FGF2 membrane translocation into the extracellular space. eLife 2024; 12:RP88579. [PMID: 38252473 PMCID: PMC10945597 DOI: 10.7554/elife.88579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2024] Open
Abstract
Fibroblast growth factor 2 (FGF2) exits cells by direct translocation across the plasma membrane, a type I pathway of unconventional protein secretion. This process is initiated by phosphatidylinositol-4,5-bisphosphate (PI(4,5)P2)-dependent formation of highly dynamic FGF2 oligomers at the inner plasma membrane leaflet, inducing the formation of lipidic membrane pores. Cell surface heparan sulfate chains linked to glypican-1 (GPC1) capture FGF2 at the outer plasma membrane leaflet, completing FGF2 membrane translocation into the extracellular space. While the basic steps of this pathway are well understood, the molecular mechanism by which FGF2 oligomerizes on membrane surfaces remains unclear. In the current study, we demonstrate the initial step of this process to depend on C95-C95 disulfide-bridge-mediated FGF2 dimerization on membrane surfaces, producing the building blocks for higher FGF2 oligomers that drive the formation of membrane pores. We find FGF2 with a C95A substitution to be defective in oligomerization, pore formation, and membrane translocation. Consistently, we demonstrate a C95A variant of FGF2 to be characterized by a severe secretion phenotype. By contrast, while also important for efficient FGF2 secretion from cells, a second cysteine residue on the molecular surface of FGF2 (C77) is not involved in FGF2 oligomerization. Rather, we find C77 to be part of the interaction interface through which FGF2 binds to the α1 subunit of the Na,K-ATPase, the landing platform for FGF2 at the inner plasma membrane leaflet. Using cross-linking mass spectrometry, atomistic molecular dynamics simulations combined with a machine learning analysis and cryo-electron tomography, we propose a mechanism by which disulfide-bridged FGF2 dimers bind with high avidity to PI(4,5)P2 on membrane surfaces. We further propose a tight coupling between FGF2 secretion and the formation of ternary signaling complexes on cell surfaces, hypothesizing that C95-C95-bridged FGF2 dimers are functioning as the molecular units triggering autocrine and paracrine FGF2 signaling.
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Affiliation(s)
- Fabio Lolicato
- Heidelberg University Biochemistry CenterHeidelbergGermany
- Department of Physics, University of HelsinkiHelsinkiFinland
| | | | | | - Daniel Beyer
- Heidelberg University Biochemistry CenterHeidelbergGermany
| | | | | | - Steffen Klein
- Schaller Research Group, Department of Infectious Diseases-Virology, Heidelberg University HospitalHeidelbergGermany
| | - Petra Riegerová
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of SciencesPragueCzech Republic
| | | | | | - Xiao J Schmitt
- Institute for Chemistry and Biochemistry, Freie Universität BerlinBerlinGermany
| | - Shreyas Kaptan
- Department of Physics, University of HelsinkiHelsinkiFinland
| | - Christian Freund
- Institute for Chemistry and Biochemistry, Freie Universität BerlinBerlinGermany
| | - Martin Hof
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of SciencesPragueCzech Republic
| | - Radek Šachl
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of SciencesPragueCzech Republic
| | - Petr Chlanda
- Schaller Research Group, Department of Infectious Diseases-Virology, Heidelberg University HospitalHeidelbergGermany
| | | | - Walter Nickel
- Heidelberg University Biochemistry CenterHeidelbergGermany
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9
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Yang M, Silverstein RL. Targeting Cysteine Oxidation in Thrombotic Disorders. Antioxidants (Basel) 2024; 13:83. [PMID: 38247507 PMCID: PMC10812781 DOI: 10.3390/antiox13010083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 12/29/2023] [Accepted: 01/05/2024] [Indexed: 01/23/2024] Open
Abstract
Oxidative stress increases the risk for clinically significant thrombotic events, yet the mechanisms by which oxidants become prothrombotic are unclear. In this review, we provide an overview of cysteine reactivity and oxidation. We then highlight recent findings on cysteine oxidation events in oxidative stress-related thrombosis. Special emphasis is on the signaling pathway induced by a platelet membrane protein, CD36, in dyslipidemia, and by protein disulfide isomerase (PDI), a member of the thiol oxidoreductase family of proteins. Antioxidative and chemical biology approaches to target cysteine are discussed. Lastly, the knowledge gaps in the field are highlighted as they relate to understanding how oxidative cysteine modification might be targeted to limit thrombosis.
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Affiliation(s)
- Moua Yang
- Division of Hemostasis and Thrombosis, Beth Israel Deaconess Medical Center, Harvard Medical School, 3 Blackfan Circle, CLS-924, Boston, MA 02115, USA
| | - Roy L. Silverstein
- Department of Medicine, Medical College of Wisconsin, Hub 8745, 8701 W Watertown Plank Rd., Milwaukee, WI 53226, USA
- Versiti Blood Research Institute, Milwaukee, WI 53226, USA
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10
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Kumar GS. Preparation of Oxidized and Reduced PTP4A1 for Structural and Functional Studies. Methods Mol Biol 2024; 2743:211-222. [PMID: 38147218 DOI: 10.1007/978-1-0716-3569-8_14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2023]
Abstract
The formation of a reversible disulfide bond between the catalytic cysteine and a spatially neighboring cysteine (backdoor) in protein tyrosine phosphatases (PTPs) serves as a critical regulatory mechanism for maintaining the activity of protein tyrosine phosphatases. The failure of such protection results in the formation of irreversibly oxidized cysteines into sulfonic acid in a highly oxidative cellular environment in the presence of free radicals. Hence, it is important to develop methods to interconvert PTPs into reduced and oxidized forms to understand their catalytic function in vitro. Protein tyrosine phosphatase 4A type 1 (PTP4A1), a dual-specificity phosphatase, is catalytically active in the reduced form. Unexpectedly, also its oxidized form performs a key biological function in systemic sclerosis (SSc) by forming a kinase-phosphatase complex with Src kinases. Thus, we developed simple and efficient protocols for producing oxidized and reduced PTP4A1 to elucidate their biological function, which can be extended to study other protein tyrosine phosphatases and other recombinantly produced proteins.
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Affiliation(s)
- Ganesan Senthil Kumar
- Integrative Structural Biology Laboratory, National Institute of Immunology, New Delhi, India.
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11
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Londhe AD, Boivin B. Measuring the Reversible Oxidation of Protein Tyrosine Phosphatases Using a Modified Cysteinyl-Labeling Assay. Methods Mol Biol 2024; 2743:223-237. [PMID: 38147219 DOI: 10.1007/978-1-0716-3569-8_15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2023]
Abstract
The modified cysteinyl-labeling assay enables the labeling, enrichment, and detection of all members of the protein tyrosine phosphatase (PTP) superfamily that become reversibly oxidized in cells to facilitate phosphorylation-dependent signaling. In this chapter, we describe the method in detail and highlight the pitfalls of avoiding post-lysis oxidation of PTPs to measure the dynamic and transient oxidation and reduction of PTPs in cell signaling.
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Affiliation(s)
- Avinash D Londhe
- Department of Nanobioscience, College of Nanoscale Science and Engineering, SUNY Polytechnic Institute, Albany, NY, USA
| | - Benoit Boivin
- Department of Nanobioscience, College of Nanoscale Science and Engineering, SUNY Polytechnic Institute, Albany, NY, USA.
- Department of Nanoscale Science and Engineering, University at Albany, Albany, NY, USA.
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12
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Rodriguez-Colman MJ, Dansen TB, Burgering BMT. FOXO transcription factors as mediators of stress adaptation. Nat Rev Mol Cell Biol 2024; 25:46-64. [PMID: 37710009 DOI: 10.1038/s41580-023-00649-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/01/2023] [Indexed: 09/16/2023]
Abstract
The forkhead box protein O (FOXO, consisting of FOXO1, FOXO3, FOXO4 and FOXO6) transcription factors are the mammalian orthologues of Caenorhabditis elegans DAF-16, which gained notoriety for its capability to double lifespan in the absence of daf-2 (the gene encoding the worm insulin receptor homologue). Since then, research has provided many mechanistic details on FOXO regulation and FOXO activity. Furthermore, conditional knockout experiments have provided a wealth of data as to how FOXOs control development and homeostasis at the organ and organism levels. The lifespan-extending capabilities of DAF-16/FOXO are highly correlated with their ability to induce stress response pathways. Exogenous and endogenous stress, such as cellular redox stress, are considered the main drivers of the functional decline that characterizes ageing. Functional decline often manifests as disease, and decrease in FOXO activity indeed negatively impacts on major age-related diseases such as cancer and diabetes. In this context, the main function of FOXOs is considered to preserve cellular and organismal homeostasis, through regulation of stress response pathways. Paradoxically, the same FOXO-mediated responses can also aid the survival of dysfunctional cells once these eventually emerge. This general property to control stress responses may underlie the complex and less-evident roles of FOXOs in human lifespan as opposed to model organisms such as C. elegans.
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Affiliation(s)
| | - Tobias B Dansen
- Center for Molecular Medicine, University Medical Center Utrecht, Utrecht, Netherlands
| | - Boudewijn M T Burgering
- Center for Molecular Medicine, University Medical Center Utrecht, Utrecht, Netherlands.
- Oncode Institute, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht, Netherlands.
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13
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Camargo LL, Wang Y, Rios FJ, McBride M, Montezano AC, Touyz RM. Oxidative Stress and Endoplasmic Reticular Stress Interplay in the Vasculopathy of Hypertension. Can J Cardiol 2023; 39:1874-1887. [PMID: 37875177 DOI: 10.1016/j.cjca.2023.10.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2023] [Revised: 10/19/2023] [Accepted: 10/19/2023] [Indexed: 10/26/2023] Open
Abstract
Under physiologic conditions, reactive oxygen species (ROS) function as signalling molecules that control cell function. However, in pathologic conditions, increased generation of ROS triggers oxidative stress, which plays a role in vascular changes associated with hypertension, including endothelial dysfunction, vascular reactivity, and arterial remodelling (termed the vasculopathy of hypertension). The major source of ROS in the vascular system is NADPH oxidase (NOX). Increased NOX activity drives vascular oxidative stress in hypertension. Molecular mechanisms underlying vascular damage in hypertension include activation of redox-sensitive signalling pathways, post-translational modification of proteins, and oxidative damage of DNA and cytoplasmic proteins. In addition, oxidative stress leads to accumulation of proteins in the endoplasmic reticulum (ER) (termed ER stress), with consequent activation of the unfolded protein response (UPR). ER stress is emerging as a potential player in hypertension as abnormal protein folding in the ER leads to oxidative stress and dysregulated activation of the UPR promotes inflammation and injury in vascular and cardiac cells. In addition, the ER engages in crosstalk with exogenous sources of ROS, such as mitochondria and NOX, which can amplify redox processes. Here we provide an update of the role of ROS and NOX in hypertension and discuss novel concepts on the interplay between oxidative stress and ER stress.
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Affiliation(s)
- Livia L Camargo
- Research Institute of the McGill University Health Centre, Montréal, Québec, Canada.
| | - Yu Wang
- School of Cardiovascular and Metabolic Health, University of Glasgow, Glasgow, Scotland, United Kingdom
| | - Francisco J Rios
- Research Institute of the McGill University Health Centre, Montréal, Québec, Canada
| | - Martin McBride
- School of Cardiovascular and Metabolic Health, University of Glasgow, Glasgow, Scotland, United Kingdom
| | - Augusto C Montezano
- Research Institute of the McGill University Health Centre, Montréal, Québec, Canada
| | - Rhian M Touyz
- Research Institute of the McGill University Health Centre, Montréal, Québec, Canada; McGill University, Department of Medicine and Department of Family Medicine, Montréal, Québec, Canada.
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14
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Cao M, Day AM, Galler M, Latimer HR, Byrne DP, Foy TW, Dwyer E, Bennett E, Palmer J, Morgan BA, Eyers PA, Veal EA. A peroxiredoxin-P38 MAPK scaffold increases MAPK activity by MAP3K-independent mechanisms. Mol Cell 2023; 83:3140-3154.e7. [PMID: 37572670 DOI: 10.1016/j.molcel.2023.07.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 05/19/2023] [Accepted: 07/14/2023] [Indexed: 08/14/2023]
Abstract
Peroxiredoxins (Prdxs) utilize reversibly oxidized cysteine residues to reduce peroxides and promote H2O2 signal transduction, including H2O2-induced activation of P38 MAPK. Prdxs form H2O2-induced disulfide complexes with many proteins, including multiple kinases involved in P38 MAPK signaling. Here, we show that a genetically encoded fusion between a Prdx and P38 MAPK is sufficient to hyperactivate the kinase in yeast and human cells by a mechanism that does not require the H2O2-sensing cysteine of the Prdx. We demonstrate that a P38-Prdx fusion protein compensates for loss of the yeast scaffold protein Mcs4 and MAP3K activity, driving yeast into mitosis. Based on our findings, we propose that the H2O2-induced formation of Prdx-MAPK disulfide complexes provides an alternative scaffold and signaling platform for MAPKK-MAPK signaling. The demonstration that formation of a complex with a Prdx is sufficient to modify the activity of a kinase has broad implications for peroxide-based signal transduction in eukaryotes.
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Affiliation(s)
- Min Cao
- Newcastle University Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - Alison M Day
- Newcastle University Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - Martin Galler
- Newcastle University Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - Heather R Latimer
- Newcastle University Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - Dominic P Byrne
- Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK
| | - Thomas W Foy
- Newcastle University Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - Emilia Dwyer
- Newcastle University Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - Elise Bennett
- Newcastle University Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - Jeremy Palmer
- Newcastle University Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - Brian A Morgan
- Newcastle University Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - Patrick A Eyers
- Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK
| | - Elizabeth A Veal
- Newcastle University Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK.
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15
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Holendova B, Plecita-Hlavata L. Cysteine residues in signal transduction and its relevance in pancreatic beta cells. Front Endocrinol (Lausanne) 2023; 14:1221520. [PMID: 37455926 PMCID: PMC10339824 DOI: 10.3389/fendo.2023.1221520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Accepted: 06/13/2023] [Indexed: 07/18/2023] Open
Abstract
Cysteine is one of the least abundant but most conserved amino acid residues in proteins, playing a role in their structure, metal binding, catalysis, and redox chemistry. Thiols present in cysteines can be modified by post-translational modifications like sulfenylation, acylation, or glutathionylation, regulating protein activity and function and serving as signals. Their modification depends on their position in the structure, surrounding amino acids, solvent accessibility, pH, etc. The most studied modifications are the redox modifications by reactive oxygen, nitrogen, and sulfur species, leading to reversible changes that serve as cell signals or irreversible changes indicating oxidative stress and cell damage. Selected antioxidants undergoing reversible oxidative modifications like peroxiredoxin-thioredoxin system are involved in a redox-relay signaling that can propagate to target proteins. Cysteine thiols can also be modified by acyl moieties' addition (derived from lipid metabolism), resulting in protein functional modification or changes in protein anchoring in the membrane. In this review, we update the current knowledge on cysteine modifications and their consequences in pancreatic β-cells. Because β-cells exhibit well-balanced redox homeostasis, the redox modifications of cysteines here serve primarily for signaling purposes. Similarly, lipid metabolism provides regulatory intermediates that have been shown to be necessary in addition to redox modifications for proper β-cell function and, in particular, for efficient insulin secretion. On the contrary, the excess of reactive oxygen, nitrogen, and sulfur species and the imbalance of lipids under pathological conditions cause irreversible changes and contribute to oxidative stress leading to cell failure and the development of type 2 diabetes.
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Affiliation(s)
| | - Lydie Plecita-Hlavata
- Laboratory of Pancreatic Islet Research, Institute of Physiology, Czech Academy of Sciences, Prague, Czechia
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16
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Chaudière J. Biological and Catalytic Properties of Selenoproteins. Int J Mol Sci 2023; 24:10109. [PMID: 37373256 DOI: 10.3390/ijms241210109] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 06/06/2023] [Accepted: 06/08/2023] [Indexed: 06/29/2023] Open
Abstract
Selenocysteine is a catalytic residue at the active site of all selenoenzymes in bacteria and mammals, and it is incorporated into the polypeptide backbone by a co-translational process that relies on the recoding of a UGA termination codon into a serine/selenocysteine codon. The best-characterized selenoproteins from mammalian species and bacteria are discussed with emphasis on their biological function and catalytic mechanisms. A total of 25 genes coding for selenoproteins have been identified in the genome of mammals. Unlike the selenoenzymes of anaerobic bacteria, most mammalian selenoenzymes work as antioxidants and as redox regulators of cell metabolism and functions. Selenoprotein P contains several selenocysteine residues and serves as a selenocysteine reservoir for other selenoproteins in mammals. Although extensively studied, glutathione peroxidases are incompletely understood in terms of local and time-dependent distribution, and regulatory functions. Selenoenzymes take advantage of the nucleophilic reactivity of the selenolate form of selenocysteine. It is used with peroxides and their by-products such as disulfides and sulfoxides, but also with iodine in iodinated phenolic substrates. This results in the formation of Se-X bonds (X = O, S, N, or I) from which a selenenylsulfide intermediate is invariably produced. The initial selenolate group is then recycled by thiol addition. In bacterial glycine reductase and D-proline reductase, an unusual catalytic rupture of selenium-carbon bonds is observed. The exchange of selenium for sulfur in selenoproteins, and information obtained from model reactions, suggest that a generic advantage of selenium compared with sulfur relies on faster kinetics and better reversibility of its oxidation reactions.
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Affiliation(s)
- Jean Chaudière
- CBMN (CNRS, UMR 5248), University of Bordeaux, 33600 Pessac, France
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17
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Machado IF, Miranda RG, Dorta DJ, Rolo AP, Palmeira CM. Targeting Oxidative Stress with Polyphenols to Fight Liver Diseases. Antioxidants (Basel) 2023; 12:1212. [PMID: 37371941 DOI: 10.3390/antiox12061212] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 05/26/2023] [Accepted: 05/31/2023] [Indexed: 06/29/2023] Open
Abstract
Reactive oxygen species (ROS) are important second messengers in many metabolic processes and signaling pathways. Disruption of the balance between ROS generation and antioxidant defenses results in the overproduction of ROS and subsequent oxidative damage to biomolecules and cellular components that disturb cellular function. Oxidative stress contributes to the initiation and progression of many liver pathologies such as ischemia-reperfusion injury (LIRI), non-alcoholic fatty liver disease (NAFLD), and hepatocellular carcinoma (HCC). Therefore, controlling ROS production is an attractive therapeutic strategy in relation to their treatment. In recent years, increasing evidence has supported the therapeutic effects of polyphenols on liver injury via the regulation of ROS levels. In the current review, we summarize the effects of polyphenols, such as quercetin, resveratrol, and curcumin, on oxidative damage during conditions that induce liver injury, such as LIRI, NAFLD, and HCC.
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Affiliation(s)
- Ivo F Machado
- CNC-Center for Neuroscience and Cell Biology, CIBB-Center for Innovative Biomedicine and Biotechnology, University of Coimbra, 3000 Coimbra, Portugal
- IIIUC-Institute of Interdisciplinary Research, University of Coimbra, 3000 Coimbra, Portugal
| | - Raul G Miranda
- School of Pharmaceutical Science of Ribeirão Preto, University of São Paulo, São Paulo 14040, Brazil
| | - Daniel J Dorta
- Department of Chemistry, Faculty of Philosophy, Sciences and Letters of Ribeirão Preto, University of São Paulo, Ribeirão Preto 14040, Brazil
| | - Anabela P Rolo
- CNC-Center for Neuroscience and Cell Biology, CIBB-Center for Innovative Biomedicine and Biotechnology, University of Coimbra, 3000 Coimbra, Portugal
- Department of Life Sciences, University of Coimbra, 3000 Coimbra, Portugal
| | - Carlos M Palmeira
- CNC-Center for Neuroscience and Cell Biology, CIBB-Center for Innovative Biomedicine and Biotechnology, University of Coimbra, 3000 Coimbra, Portugal
- Department of Life Sciences, University of Coimbra, 3000 Coimbra, Portugal
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18
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Fujii J, Soma Y, Matsuda Y. Biological Action of Singlet Molecular Oxygen from the Standpoint of Cell Signaling, Injury and Death. Molecules 2023; 28:molecules28104085. [PMID: 37241826 DOI: 10.3390/molecules28104085] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 05/11/2023] [Accepted: 05/12/2023] [Indexed: 05/28/2023] Open
Abstract
Energy transfer to ground state triplet molecular oxygen results in the generation of singlet molecular oxygen (1O2), which has potent oxidizing ability. Irradiation of light, notably ultraviolet A, to a photosensitizing molecule results in the generation of 1O2, which is thought to play a role in causing skin damage and aging. It should also be noted that 1O2 is a dominant tumoricidal component that is generated during the photodynamic therapy (PDT). While type II photodynamic action generates not only 1O2 but also other reactive species, endoperoxides release pure 1O2 upon mild exposure to heat and, hence, are considered to be beneficial compounds for research purposes. Concerning target molecules, 1O2 preferentially reacts with unsaturated fatty acids to produce lipid peroxidation. Enzymes that contain a reactive cysteine group at the catalytic center are vulnerable to 1O2 exposure. Guanine base in nucleic acids is also susceptible to oxidative modification, and cells carrying DNA with oxidized guanine units may experience mutations. Since 1O2 is produced in various physiological reactions in addition to photodynamic reactions, overcoming technical challenges related to its detection and methods used for its generation would allow its potential functions in biological systems to be better understood.
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Affiliation(s)
- Junichi Fujii
- Department of Biochemistry and Molecular Biology, Graduate School of Medical Science, Yamagata University, Yamagata 990-9585, Japan
| | - Yuya Soma
- Graduate School of Nursing, Yamagata University Faculty of Medicine, Yamagata 990-9585, Japan
| | - Yumi Matsuda
- Graduate School of Nursing, Yamagata University Faculty of Medicine, Yamagata 990-9585, Japan
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19
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Meng J, Liu HC, Guo YY, Wang F, Pi DJ, Yu QZ. Discovery of a triphenylamine-benzofuran derivative as fluorescent probe for hydrogen polysulfide in tea samples. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2023; 288:122191. [PMID: 36463623 DOI: 10.1016/j.saa.2022.122191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 11/20/2022] [Accepted: 11/25/2022] [Indexed: 06/17/2023]
Abstract
In this work, a novel triphenylamine-benzofuran derived fluorescent probe, TBF-SS, was developed for detecting hydrogen polysulfide in tea samples and intracellular imaging. TBF-SS showed the practical advantages including high sensitivity (LOD = 0.01 μM), high selectivity, rapid response (within 15 min), and steadiness in various environmental conditions. The detecting system was steady within pH range of 6.0-11.0 and temperature range of 20-55 °C. The probe TBF-SS could guarantee the stable detection of H2Sn for 7 d in storage of either solid or solution. In particular, in the application of various tea samples with different brewing times and testing temperatures, the recovery percentages varied in the range of 95.22 % to 105.0 %. Therefore accurate monitoring of H2Sn could be achieved by using the probe TBF-SS. In addition, TBF-SS could monitor the exogenous level, the β-lapachone-induced generation and the tea-sample-treated introduction of H2Sn in living MCF-7 cells. This work might inspire the improvement of the serviceability of fluorescent implements.
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Affiliation(s)
- Juan Meng
- College of Preparatory Education, Guangxi Minzu University, Nanning 530006, PR China
| | - Hong-Cun Liu
- Guangxi Key Laboratory for Polysaccharide Materials and Modifications, School of Marine Sciences and Biotechnology, Guangxi Minzu University, Nanning 530006, PR China.
| | - Yang-Yang Guo
- Chemical and Biological Engineering, Guangxi Normal University for Nationalities, Chongzuo 532200, PR China
| | - Fang Wang
- Guangxi Key Laboratory for Polysaccharide Materials and Modifications, School of Marine Sciences and Biotechnology, Guangxi Minzu University, Nanning 530006, PR China
| | - Du-Juan Pi
- Guangxi Key Laboratory for Polysaccharide Materials and Modifications, School of Marine Sciences and Biotechnology, Guangxi Minzu University, Nanning 530006, PR China
| | - Qian-Zhou Yu
- Guangxi Key Laboratory for Polysaccharide Materials and Modifications, School of Marine Sciences and Biotechnology, Guangxi Minzu University, Nanning 530006, PR China
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20
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Yarnall MT, Kim SH, Korntner S, Bishop AC. Destabilization of the SHP2 and SHP1 protein tyrosine phosphatase domains by a non-conserved "backdoor" cysteine. Biochem Biophys Rep 2022; 32:101370. [PMID: 36275931 PMCID: PMC9578986 DOI: 10.1016/j.bbrep.2022.101370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 10/11/2022] [Accepted: 10/11/2022] [Indexed: 11/06/2022] Open
Abstract
Protein tyrosine phosphatases (PTPs) are critical regulators of cellular signal transduction that catalyze the hydrolytic dephosphorylation of phosphotyrosine in substrate proteins. Among several conserved features in classical PTP domains are an active-site cysteine residue that is necessary for catalysis and a "backdoor" cysteine residue that can serve to protect the active-site cysteine from irreversible oxidation. Curiously, two biologically important phosphatases, Src homology domain-containing PTPs 2 and 1 (SHP2 and SHP1), each contain an additional backdoor cysteine residue at a position of the PTP domain that is occupied by proline in almost all other classical PTPs (position 333 in human SHP2 numbering). Here we show that the presence of cysteine 333 significantly destabilizes the fold of the PTP domains in the SHPs. We find that replacement of cysteine 333 with proline confers increased thermal stability on the SHP2 and SHP1 PTP domains, as measured by temperature-dependent activity assays and differential scanning fluorimetry. Conversely, we show that substantial destabilization of the PTP-domain fold is conferred by introduction of a non-natural cysteine residue in a non-SHP PTP that contains proline at the 333 position. It has previously been suggested that the extra backdoor cysteine of the SHP PTPs may work in tandem with the conserved backdoor cysteine to provide protection from irreversible oxidative enzyme inactivation. If so, our current results suggest that, during the course of mammalian evolution, the SHP proteins have developed extra protection from oxidation at the cost of the thermal instability that is conferred by the presence of their PTP domains' second backdoor cysteine.
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Affiliation(s)
| | - Sean H. Kim
- Amherst College, Department of Chemistry, Amherst, MA, 01002, USA
| | - Samuel Korntner
- Amherst College, Department of Chemistry, Amherst, MA, 01002, USA
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