1
|
Lv S, Xu F, Fan Y, Ding K, Li Z. Cyclopropenone, Cyclopropeniminium Ion, and Cyclopropenethione as Novel Electrophilic Warheads for Potential Target Discovery of Triple-Negative Breast Cancer. J Med Chem 2023; 66:2851-2864. [PMID: 36762554 DOI: 10.1021/acs.jmedchem.2c01889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Because very few targets are currently available for drug development, triple-negative breast cancer (TNBC) has been defined as one of the most difficult diseases for chemotherapy. Herein, we describe a suite of novel electrophilic warheads, which we have used in chemical proteomics studies in a search for potential targets for TNBC. Binding site analysis revealed that these warheads can modify not only highly nucleophilic residues, including cysteine and lysine, but also weakly nucleophilic residues. Cys12 of Kirsten rat sarcoma (KRASG12C) was successfully labeled by cyclopropenone and the cyclopropeniminium ions. Moderate inhibitory activity against TNBC cells was achieved with these novel electrophile-based probes. Activity-based protein profiling reveals that these electrophiles can covalently label a series of essential protein targets, including ALDH2, LRPPRC, and FABP5 from MDA-MB-231 cells. Further functional validation experiments demonstrated that FABP5 might be a potential target for TNBC.
Collapse
Affiliation(s)
- Shumin Lv
- International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Development (MOE), MOE Key Laboratory of Tumor Molecular Biology, School of Pharmacy, Jinan University, Guangzhou 510632, China
| | - Fang Xu
- International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Development (MOE), MOE Key Laboratory of Tumor Molecular Biology, School of Pharmacy, Jinan University, Guangzhou 510632, China
| | - Youlong Fan
- International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Development (MOE), MOE Key Laboratory of Tumor Molecular Biology, School of Pharmacy, Jinan University, Guangzhou 510632, China
| | - Ke Ding
- International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Development (MOE), MOE Key Laboratory of Tumor Molecular Biology, School of Pharmacy, Jinan University, Guangzhou 510632, China
| | - Zhengqiu Li
- International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Development (MOE), MOE Key Laboratory of Tumor Molecular Biology, School of Pharmacy, Jinan University, Guangzhou 510632, China
| |
Collapse
|
2
|
Paluchova V, Cajka T, Durand T, Vigor C, Dodia C, Chatterjee S, Fisher AB, Kuda O. The role of peroxiredoxin 6 in biosynthesis of FAHFAs. Free Radic Biol Med 2022; 193:787-794. [PMID: 36403738 DOI: 10.1016/j.freeradbiomed.2022.11.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Accepted: 11/09/2022] [Indexed: 11/20/2022]
Abstract
Peroxiredoxin 6 (Prdx6) is a multifunctional enzyme, a unique member of the peroxiredoxin family, with an important role in antioxidant defense. Moreover, it has also been linked with the biosynthesis of anti-inflammatory and anti-diabetic lipids called fatty acid esters of hydroxy fatty acids (FAHFAs) and many diseases, including cancer, inflammation, and metabolic disorders. Here, we performed metabolomic and lipidomic profiling of subcutaneous adipose tissue from mouse models with genetically modified Prdx6. Deletion of Prdx6 resulted in reduced levels of FAHFAs containing 13-hydroxylinoleic acid (13-HLA). Mutation of Prdx6 C47S impaired the glutathione peroxidase activity and reduced FAHFA levels, while D140A mutation, responsible for phospholipase A2 activity, showed only minor effects. Targeted analysis of oxidized phospholipids and triacylglycerols in adipocytes highlighted a correlation between FAHFA and hydroxy fatty acid production by Prdx6 or glutathione peroxidase 4. FAHFA regioisomer abundance was negatively affected by the Prdx6 deletion, and this effect was more pronounced in longer and more unsaturated FAHFAs. The predicted protein model of Prdx6 suggested that the monomer-dimer transition mechanism might be involved in the repair of longer-chain peroxidized phospholipids bound over two monomers and that the role of Prdx6 in FAHFA synthesis might be restricted to branching positions further from carbon 9. In conclusion, our work linked the peroxidase activity of Prdx6 with the levels of FAHFAs in adipose tissue.
Collapse
Affiliation(s)
- Veronika Paluchova
- Institute of Physiology of the Czech Academy of Sciences, Videnska 1083, 14220, Prague 4, Czech Republic; First Faculty of Medicine, Charles University, Katerinska 32, Prague, 12108, Czech Republic
| | - Tomas Cajka
- Institute of Physiology of the Czech Academy of Sciences, Videnska 1083, 14220, Prague 4, Czech Republic
| | - Thierry Durand
- Institut des Biomolecules Max Mousseron, CNRS, ENSCM, University Montpellier, 34093, Montpellier, France
| | - Claire Vigor
- Institut des Biomolecules Max Mousseron, CNRS, ENSCM, University Montpellier, 34093, Montpellier, France
| | - Chandra Dodia
- Institute for Environmental Medicine of the Department of Physiology, University of Pennsylvania, 3620 Hamilton Walk, 1 John Morgan Building, USA
| | - Shampa Chatterjee
- Institute for Environmental Medicine of the Department of Physiology, University of Pennsylvania, 3620 Hamilton Walk, 1 John Morgan Building, USA
| | - Aron B Fisher
- Institute for Environmental Medicine of the Department of Physiology, University of Pennsylvania, 3620 Hamilton Walk, 1 John Morgan Building, USA
| | - Ondrej Kuda
- Institute of Physiology of the Czech Academy of Sciences, Videnska 1083, 14220, Prague 4, Czech Republic.
| |
Collapse
|
3
|
Structural basis of peroxidase catalytic cycle of human Prdx6. Sci Rep 2020; 10:17416. [PMID: 33060708 PMCID: PMC7566464 DOI: 10.1038/s41598-020-74052-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 09/24/2020] [Indexed: 11/23/2022] Open
Abstract
Peroxiredoxin 6 (Prdx6) is a ubiquitously expressed antioxidant non-selenium glutathione peroxidase that is known to play a major role in various physiological and pathological processes. It belongs to the family of peroxidases (referred to as Peroxiredoxins, Prdx’s) that work independently of any prosthetic groups or co-factors, and instead utilize a peroxidatic thiol residue for peroxide reduction. Mammalian Prdx’s are classified according to the number of Cys implicated in their catalytic activity by the formation of either inter-molecular (typical 2-Cys, Prdx1–4) or intra-molecular (atypical 2-Cys, Prdx5) disulfide bond, or non-covalent interactions (1-Cys, Prdx6). The typical and atypical 2-Prdx’s have been identified to show decamer/dimer and monomer/dimer transition, respectively, upon oxidation of their peroxidatic cysteine. However, the alterations in the oligomeric status of Prdx6 as a function of peroxidatic thiol’s redox state are still ambiguous. While the crystal structure of recombinant human Prdx6 is resolved as a dimer, the solution structures are reported to have both monomers and dimers. In the present study, we have employed several spectroscopic and electrophoretic probes to discern the impact of change in the redox status of peroxidatic cysteine on conformation and oligomeric status of Prdx6. Our study indicates Prdx6′s peroxidase activity to be a redox-based conformation driven process which essentially involves monomer–dimer transition.
Collapse
|
4
|
Zhang L, Zhang Y, Wang Z, Chen Y, Li R. Intermittent hyperbaric oxygen exposure mobilizing peroxiredoxin 6 to prevent oxygen toxicity. J Physiol Sci 2019; 69:779-790. [PMID: 31286450 PMCID: PMC10716995 DOI: 10.1007/s12576-019-00694-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Accepted: 06/26/2019] [Indexed: 01/05/2023]
Abstract
Intermittent hyperbaric oxygen exposure (IE-HBO) can protect the body against oxygen toxicity, but the underlying mechanisms are not very clear. Peroxiredoxin 6 (Prdx6) is a special endogenous antioxidative protein. We explored if the protective effects of IE-HBO are related to Prdx6. Mice were exposed to 280 kPa O2 for 60 min, followed by 30-min exposure to 20% O2/N2 mixture with equal pressure, repeated for six cycles. The Prdx6 protein level and non-selenium glutathione peroxidase (NSGPx) activity in the brain and lungs were then measured and the injury degree of lung and the oxidation level of brain and lung were evaluated. On this basis, the relationship between Prdx6 and IE-HBO's protection was explored. Generally, both IE-HBO and continuous exposure to HBO (CE-HBO) could increase the protein and mRNA levels of Prdx6, and such increases were more significant 24 h after cessation of exposure; moreover, the Prdx6 level of IE-HBO was higher than that of CE-HBO in both brain and lung, also more significantly 24 h after cessation of exposure. In addition, IE-HBO exposure could more effectively potentiate the activity of NSGPx and increase GSH content in brain and lung tissues. At the same time, it could reduce oxidation products in these tissues. IE-HBO could also provide protection for the lungs against injuries resulting from prolonged HBO exposure. These data showed that IE-HBO can potentiate the production and the activity of Prdx6 and consequently mitigate oxidative damages in brain and lungs. The influences of IE-HBO on Prdx6 may form an important basis for its protection against oxygen toxicity.
Collapse
Affiliation(s)
- Lichao Zhang
- Department of Pharmacy, Shanghai Hospital of Traditional Chinese Medicine, Shanghai, China
| | - Yanan Zhang
- Department of Diving Medicine, Faculty of Naval Medicine, Second Military Medical University, Shanghai, 200433, China
| | - Zhongzhuang Wang
- Department of Pharmacy, Changhai Hospital, Second Military Medical University, Shanghai, China
| | - Yuliang Chen
- Department of Nautical and Aviation Medicine Center, Navy General Hospital, Beijing, China
| | - Runping Li
- Department of Diving Medicine, Faculty of Naval Medicine, Second Military Medical University, Shanghai, 200433, China.
| |
Collapse
|
5
|
Antioxidants Special Issue: Peroxiredoxin 6 as a Unique Member of the Peroxiredoxin Family. Antioxidants (Basel) 2019; 8:antiox8040107. [PMID: 31010116 PMCID: PMC6523856 DOI: 10.3390/antiox8040107] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 04/17/2019] [Indexed: 12/15/2022] Open
|
6
|
Forshaw TE, Holmila R, Nelson KJ, Lewis JE, Kemp ML, Tsang AW, Poole LB, Lowther WT, Furdui CM. Peroxiredoxins in Cancer and Response to Radiation Therapies. Antioxidants (Basel) 2019; 8:antiox8010011. [PMID: 30609657 PMCID: PMC6356878 DOI: 10.3390/antiox8010011] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Revised: 12/23/2018] [Accepted: 12/25/2018] [Indexed: 12/11/2022] Open
Abstract
Peroxiredoxins have a long-established cellular function as regulators of redox metabolism by catalyzing the reduction of peroxides (e.g., H2O2, lipid peroxides) with high catalytic efficiency. This activity is also critical to the initiation and relay of both phosphorylation and redox signaling in a broad range of pathophysiological contexts. Under normal physiological conditions, peroxiredoxins protect normal cells from oxidative damage that could promote oncogenesis (e.g., environmental stressors). In cancer, higher expression level of peroxiredoxins has been associated with both tumor growth and resistance to radiation therapies. However, this relationship between the expression of peroxiredoxins and the response to radiation is not evident from an analysis of data in The Cancer Genome Atlas (TCGA) or NCI60 panel of cancer cell lines. The focus of this review is to summarize the current experimental knowledge implicating this class of proteins in cancer, and to provide a perspective on the value of targeting peroxiredoxins in the management of cancer. Potential biases in the analysis of the TCGA data with respect to radiation resistance are also highlighted.
Collapse
Affiliation(s)
- Tom E Forshaw
- Department of Internal Medicine, Section on Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA.
| | - Reetta Holmila
- Department of Internal Medicine, Section on Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA.
| | - Kimberly J Nelson
- Department of Biochemistry, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA.
| | - Joshua E Lewis
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA 30332, USA.
| | - Melissa L Kemp
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA 30332, USA.
| | - Allen W Tsang
- Department of Internal Medicine, Section on Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA.
| | - Leslie B Poole
- Department of Biochemistry, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA.
| | - W Todd Lowther
- Department of Biochemistry, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA.
| | - Cristina M Furdui
- Department of Internal Medicine, Section on Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA.
| |
Collapse
|
7
|
Zhou S, Dodia C, Feinstein SI, Harper S, Forman HJ, Speicher DW, Fisher AB. Oxidation of Peroxiredoxin 6 in the Presence of GSH Increases its Phospholipase A₂ Activity at Cytoplasmic pH. Antioxidants (Basel) 2018; 8:antiox8010004. [PMID: 30586895 PMCID: PMC6357108 DOI: 10.3390/antiox8010004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Revised: 12/05/2018] [Accepted: 12/18/2018] [Indexed: 01/25/2023] Open
Abstract
The expression of the phospholipase A2 activity (aiPLA2) of peroxiredoxin 6 (Prdx6) in the cell cytoplasm is physiologically relevant for the repair of peroxidized cell membranes, but aiPLA2 assay in vitro indicates that, unlike assay at pH 4, activity at cytosolic pH is essentially absent with non-oxidized substrate. However, the addition of glutathione (GSH) to the assay medium significantly increased aiPLA2 activity at cytosolic pH, while oxidized GSH (GSSG) and several other thiols had no effect. By mass spectroscopy (ESI MS), the addition of GSH to Prdx6 paradoxically led to oxidation of its conserved Cys47 residue to a sulfinic acid. The effect of GSH on PLA2 activity was abolished by incubation under anaerobic conditions, confirming that auto-oxidation of the protein was the mechanism for the GSH effect. Analysis by circular dichroism (CD) and tryptophan fluorescence showed alterations of the protein structure in the presence of GSH. Independently of GSH, the oxidation of Prdx6 by exposure to H2O2 or the presence of oxidized phospholipid as substrate also significantly increased aiPLA2 activity at pH 7. We conclude that the oxidation of the peroxidatically active Cys47 of Prdx6 results in an increase of aiPLA2 activity at pH 7 without effect on the activity of the enzyme at pH 4.
Collapse
Affiliation(s)
- Suiping Zhou
- Institute for Environmental Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA.
| | - Chandra Dodia
- Institute for Environmental Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA.
| | - Sheldon I Feinstein
- Institute for Environmental Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA.
| | - Sandra Harper
- Center for Systems and Computational Biology, The Wistar Institute, Philadelphia, PA 19104, USA.
| | - Henry J Forman
- Leonard Davis School of Gerontology, The University of Southern California, Los Angeles, CA 19104, USA.
| | - David W Speicher
- Center for Systems and Computational Biology, The Wistar Institute, Philadelphia, PA 19104, USA.
| | - Aron B Fisher
- Institute for Environmental Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA.
| |
Collapse
|
8
|
Fisher AB. The phospholipase A 2 activity of peroxiredoxin 6. J Lipid Res 2018; 59:1132-1147. [PMID: 29716959 DOI: 10.1194/jlr.r082578] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 04/30/2018] [Indexed: 12/21/2022] Open
Abstract
Peroxiredoxin 6 (Prdx6) is a Ca2+-independent intracellular phospholipase A2 (called aiPLA2) that is localized to cytosol, lysosomes, and lysosomal-related organelles. Activity is minimal at cytosolic pH but is increased significantly with enzyme phosphorylation, at acidic pH, and in the presence of oxidized phospholipid substrate; maximal activity with phosphorylated aiPLA2 is ∼2 µmol/min/mg protein. Prdx6 is a "moonlighting" protein that also expresses glutathione peroxidase and lysophosphatidylcholine acyl transferase activities. The catalytic site for aiPLA2 activity is an S32-H26-D140 triad; S32-H26 is also the phospholipid binding site. Activity is inhibited by a serine "protease" inhibitor (diethyl p-nitrophenyl phosphate), an analog of the PLA2 transition state [1-hexadecyl-3-(trifluoroethyl)-sn-glycero-2-phosphomethanol (MJ33)], and by two naturally occurring proteins (surfactant protein A and p67phox), but not by bromoenol lactone. aiPLA2 activity has important physiological roles in the turnover (synthesis and degradation) of lung surfactant phospholipids, in the repair of peroxidized cell membranes, and in the activation of NADPH oxidase type 2 (NOX2). The enzyme has been implicated in acute lung injury, carcinogenesis, neurodegenerative diseases, diabetes, male infertility, and sundry other conditions, although its specific roles have not been well defined. Protein mutations and animal models are now available to further investigate the roles of Prdx6-aiPLA2 activity in normal and pathological physiology.
Collapse
Affiliation(s)
- Aron B Fisher
- Institute for Environmental Medicine of the Department of Physiology, University of Pennsylvania, Philadelphia, PA 19103
| |
Collapse
|
9
|
Fisher AB. Peroxiredoxin 6 in the repair of peroxidized cell membranes and cell signaling. Arch Biochem Biophys 2017; 617:68-83. [PMID: 27932289 PMCID: PMC5810417 DOI: 10.1016/j.abb.2016.12.003] [Citation(s) in RCA: 125] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Revised: 12/02/2016] [Accepted: 12/03/2016] [Indexed: 12/12/2022]
Abstract
Peroxiredoxin 6 represents a widely distributed group of peroxiredoxins that contain a single conserved cysteine in the protein monomer (1-cys Prdx). The cys when oxidized to the sulfenic form is reduced with glutathione (GSH) catalyzed by the π isoform of GSH-S-transferase. Three enzymatic activities of the protein have been described:1) peroxidase with H2O2, short chain hydroperoxides, and phospholipid hydroperoxides as substrates; 2) phospholipase A2 (PLA2); and 3) lysophosphatidylcholine acyl transferase (LPCAT). These activities have important physiological roles in antioxidant defense, turnover of cellular phospholipids, and the generation of superoxide anion via initiation of the signaling cascade for activation of NADPH oxidase (type 2). The ability of Prdx6 to reduce peroxidized cell membrane phospholipids (peroxidase activity) and also to replace the oxidized sn-2 fatty acyl group through hydrolysis/reacylation (PLA2 and LPCAT activities) provides a complete system for the repair of peroxidized cell membranes.
Collapse
Affiliation(s)
- Aron B Fisher
- Institute for Environmental Medicine of the Department of Physiology, University of Pennsylvania, 3620 Hamilton Walk, 1 John Morgan Building, Philadelphia, PA, United States.
| |
Collapse
|
10
|
Rivera-Santiago R, Harper SL, Sriswasdi S, Hembach P, Speicher DW. Full-Length Anion Exchanger 1 Structure and Interactions with Ankyrin-1 Determined by Zero Length Crosslinking of Erythrocyte Membranes. Structure 2016; 25:132-145. [PMID: 27989623 DOI: 10.1016/j.str.2016.11.017] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 11/02/2016] [Accepted: 11/18/2016] [Indexed: 11/26/2022]
Abstract
Anion exchanger 1 (AE1) is a critical transporter and the primary structural scaffold for large macromolecular complexes responsible for erythrocyte membrane flexibility and integrity. We used zero-length crosslinking and mass spectrometry to probe AE1 structures and interactions in intact erythrocyte membranes. An experimentally verified full-length model of AE1 dimers was developed by combining crosslink-defined distance constraints with homology modeling. Previously unresolved cytoplasmic loops in the AE1 C-terminal domain are packed at the domain-domain interface on the cytoplasmic face of the membrane where they anchor the N-terminal domain's location and prevent it from occluding the ion channel. Crosslinks between AE1 dimers and ankyrin-1 indicate the likely topology for AE1 tetramers and suggest that ankyrin-1 wraps around AE1 tetramers, which may stabilize this oligomer state. This interaction and interactions of AE1 with other major erythrocyte membrane proteins show that protein-protein contacts are often substantially more extensive than previously reported.
Collapse
Affiliation(s)
- Roland Rivera-Santiago
- The Center for Systems and Computational Biology and Molecular and Cellular Oncogenesis Program, The Wistar Institute, 3601 Spruce Street, Philadelphia, PA 19104, USA
| | - Sandra L Harper
- The Center for Systems and Computational Biology and Molecular and Cellular Oncogenesis Program, The Wistar Institute, 3601 Spruce Street, Philadelphia, PA 19104, USA
| | - Sira Sriswasdi
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo 113-0032, Japan
| | - Peter Hembach
- The Center for Systems and Computational Biology and Molecular and Cellular Oncogenesis Program, The Wistar Institute, 3601 Spruce Street, Philadelphia, PA 19104, USA
| | - David W Speicher
- The Center for Systems and Computational Biology and Molecular and Cellular Oncogenesis Program, The Wistar Institute, 3601 Spruce Street, Philadelphia, PA 19104, USA.
| |
Collapse
|
11
|
Zhou S, Sorokina EM, Harper S, Li H, Ralat L, Dodia C, Speicher DW, Feinstein SI, Fisher AB. Peroxiredoxin 6 homodimerization and heterodimerization with glutathione S-transferase pi are required for its peroxidase but not phospholipase A2 activity. Free Radic Biol Med 2016; 94:145-56. [PMID: 26891882 PMCID: PMC4844822 DOI: 10.1016/j.freeradbiomed.2016.02.012] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Revised: 02/09/2016] [Accepted: 02/12/2016] [Indexed: 12/11/2022]
Abstract
Peroxiredoxin 6 (Prdx6) is a unique 1-Cys member of the peroxiredoxin family with both GSH peroxidase and phospholipase A2 (PLA2) activities. It is highly expressed in the lung where it plays an important role in antioxidant defense and lung surfactant metabolism. Glutathionylation of Prdx6 mediated by its heterodimerization with GSH S-transferase π (πGST) is required for its peroxidatic catalytic cycle. Recombinant human Prdx6 crystallizes as a homodimer and sedimentation equilibrium analysis confirmed that this protein exists as a high affinity dimer in solution. Based on measurement of molecular mass, dimeric Prdx6 that was oxidized to the sulfenic acid formed a sulfenylamide during storage. After examination of the dimer interface in the crystal structure, we postulated that the hydrophobic amino acids L145 and L148 play an important role in homodimerization of Prdx6 as well as in its heterodimerization with πGST. Oxidation of Prdx6 also was required for its heterodimerization. Sedimentation equilibrium analysis and the Duolink proximity ligation assay following mutation of the L145 and L148 residues of Prdx6 to Glu indicated greatly decreased dimerization propensity reflecting the loss of hydrophobic interactions between the protein monomers. Peroxidase activity was markedly reduced by mutation at either of the Leu sites and was essentially abolished by the double mutation, while PLA2 activity was unaffected. Decreased peroxidase activity following mutation of the interfacial leucines presumably is mediated via impaired heterodimerization of Prdx6 with πGST that is required for reduction and re-activation of the oxidized enzyme.
Collapse
Affiliation(s)
- Suiping Zhou
- Institute for Environmental Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Elena M Sorokina
- Institute for Environmental Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Sandra Harper
- Center for Systems and Computational Biology, The Wistar Institute, Philadelphia, PA 19104, USA
| | - Haitao Li
- Institute for Environmental Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Luis Ralat
- Institute for Environmental Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Chandra Dodia
- Institute for Environmental Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - David W Speicher
- Center for Systems and Computational Biology, The Wistar Institute, Philadelphia, PA 19104, USA
| | - Sheldon I Feinstein
- Institute for Environmental Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Aron B Fisher
- Institute for Environmental Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA.
| |
Collapse
|
12
|
Sorokina EM, Dodia C, Zhou S, Tao JQ, Gao L, Raabe T, Feinstein SI, Fisher AB. Mutation of Serine 32 to Threonine in Peroxiredoxin 6 Preserves Its Structure and Enzymatic Function but Abolishes Its Trafficking to Lamellar Bodies. J Biol Chem 2016; 291:9268-80. [PMID: 26921317 DOI: 10.1074/jbc.m115.698894] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Indexed: 11/06/2022] Open
Abstract
Peroxiredoxin 6 (Prdx6), a bifunctional protein with phospholipase A2 (aiPLA2) and GSH peroxidase activities, protects lungs from oxidative stress and participates in lung surfactant phospholipid turnover. Prdx6 has been localized to both cytosol and lamellar bodies (LB) in lung epithelium, and its organellar targeting sequence has been identified. We propose that Prdx6 LB targeting facilitates its role in the metabolism of lung surfactant phosphatidylcholine (PC). Ser-32 has been identified as the active site in Prdx6 for aiPLA2 activity, and this activity was abolished by the mutation of serine 32 to alanine (S32A). However, aiPLA2 activity was unaffected by mutation of serine 32 in Prdx6 to threonine (S32T). Prdx6 protein expression and aiPLA2 activity were normal in the whole lung of a "knock-in" mouse model carrying an S32T mutation in the Prdx6 gene but were absent from isolated LB. Analyses by proximity ligation assay in lung sections demonstrated the inability of S32T Prdx6 to bind to the chaperone protein, 14-3-3ϵ, that is required for LB targeting. The content of total phospholipid, PC, and disaturated PC in lung tissue homogenate, bronchoalveolar lavage fluid, and lung LB was increased significantly in Prdx6-S32T mutant lungs, whereas degradation of internalized [(3)H]dipalmitoyl-PC was significantly decreased. Thus, Thr can substitute for Ser for the enzymatic activities of Prdx6 but not for its targeting to LB. These results confirm an important role for LB Prdx6 in the degradation and remodeling of lung surfactant phosphatidylcholine.
Collapse
Affiliation(s)
- Elena M Sorokina
- From the Institute for Environmental Medicine, Department of Physiology, and
| | - Chandra Dodia
- From the Institute for Environmental Medicine, Department of Physiology, and
| | - Suiping Zhou
- From the Institute for Environmental Medicine, Department of Physiology, and
| | - Jian-Qin Tao
- From the Institute for Environmental Medicine, Department of Physiology, and
| | - Ling Gao
- From the Institute for Environmental Medicine, Department of Physiology, and
| | - Tobias Raabe
- Penn Gene Targeting Core and Laboratory, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Sheldon I Feinstein
- From the Institute for Environmental Medicine, Department of Physiology, and
| | - Aron B Fisher
- From the Institute for Environmental Medicine, Department of Physiology, and
| |
Collapse
|
13
|
Fisher AB, Dodia C, Sorokina EM, Li H, Zhou S, Raabe T, Feinstein SI. A novel lysophosphatidylcholine acyl transferase activity is expressed by peroxiredoxin 6. J Lipid Res 2016; 57:587-96. [PMID: 26830860 DOI: 10.1194/jlr.m064758] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Indexed: 12/31/2022] Open
Abstract
The phospholipase A2(PLA2) activity of peroxiredoxin (Prdx)6 has important physiological roles in the synthesis of lung surfactant and in the repair of peroxidized cell membranes. These functions require the activity of a lysophospholipid acyl transferase as a critical component of the phospholipid remodeling pathway. We now describe a lysophosphatidylcholine acyl transferase (LPCAT) activity for Prdx6 that showed a strong preference for lysophosphatidylcholine (LPC) as the head group and for palmitoyl CoA in the acylation reaction. The calculated kinetic constants for acylation wereKm18 μM andVmax30 nmol/min/mg protein; theVmaxwas increased 25-fold by phosphorylation of the protein whileKmwas unchanged. Study of recombinant protein in vitro and in mouse pulmonary microvascular endothelial cells infected with a lentiviral vector construct indicated that amino acid D31 is crucial for LPCAT activity. A linear incorporation of labeled fatty acyl CoA into dipalmitoyl phosphatidylcholine (PC) indicated that LPC generated by Prdx6 PLA2activity remained bound to the enzyme for the reacylation reaction. Prdx6 is the first LPCAT enzyme with demonstrated cytoplasmic localization. Thus, Prdx6 is a complete enzyme comprising both PLA2and LPCAT activities for the remodeling pathway of PC synthesis or for repair of membrane lipid peroxidation.
Collapse
Affiliation(s)
- Aron B Fisher
- Institute for Environmental Medicine and the Department of Physiology University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
| | - Chandra Dodia
- Institute for Environmental Medicine and the Department of Physiology University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
| | - Elena M Sorokina
- Institute for Environmental Medicine and the Department of Physiology University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
| | - Haitao Li
- Institute for Environmental Medicine and the Department of Physiology University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
| | - Suiping Zhou
- Institute for Environmental Medicine and the Department of Physiology University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
| | - Tobias Raabe
- Penn Gene Targeting Core and Laboratory, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
| | - Sheldon I Feinstein
- Institute for Environmental Medicine and the Department of Physiology University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104
| |
Collapse
|
14
|
Renal peroxiredoxin 6 interacts with anion exchanger 1 and plays a novel role in pH homeostasis. Kidney Int 2016; 89:105-112. [PMID: 26398495 PMCID: PMC4705439 DOI: 10.1038/ki.2015.277] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Revised: 07/07/2015] [Accepted: 07/09/2015] [Indexed: 12/11/2022]
Abstract
Peroxiredoxin 6 (PRDX6) is one of six members of the PRDX family, which have peroxidase and antioxidant activity. PRDX6 is unique, containing only one conserved cysteine residue (C47) rather than the two found in other PRDXs. A yeast two-hybrid screen found PRDX6 to be a potential binding partner of the C-terminal tail of anion exchanger 1 (AE1), a Cl−/HCO3− exchanger basolaterally expressed in renal α-intercalated cells. PRDX6 immunostaining in human kidney was both cytoplasmic and peripheral and co-localized with AE1. Analysis of native protein showed it was largely monomeric, whereas expressed tagged protein was more dimeric. Two methionine oxidation sites were identified. In vitro and ex vivo pulldowns and immunoprecipitation assays confirmed interaction with AE1, but mutation of the conserved cysteine resulted in loss of interaction. Prdx6 knockout mice had a baseline acidosis with a major respiratory component and greater AE1 expression than wild type animals. After an oral acid challenge, PRDX6 expression increased in wild type mice, with preservation of AE1. However, AE1 expression was significantly decreased in knockout animals. Kidneys from acidified mice showed widespread proximal tubular vacuolation in wild type but not knockout animals. Knockdown of PRDX6 by siRNA in mammalian cells reduced both total and cell membrane AE1 levels. Thus, PRDX6-AE1 interaction contributes to maintenance of AE1 during cellular stress such as during metabolic acidosis.
Collapse
|
15
|
Rivera-Santiago RF, Sriswasdi S, Harper SL, Speicher DW. Probing structures of large protein complexes using zero-length cross-linking. Methods 2015; 89:99-111. [PMID: 25937394 PMCID: PMC4628899 DOI: 10.1016/j.ymeth.2015.04.031] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Revised: 04/10/2015] [Accepted: 04/24/2015] [Indexed: 02/02/2023] Open
Abstract
Structural mass spectrometry (MS) is a field with growing applicability for addressing complex biophysical questions regarding proteins and protein complexes. One of the major structural MS approaches involves the use of chemical cross-linking coupled with MS analysis (CX-MS) to identify proximal sites within macromolecules. Identified cross-linked sites can be used to probe novel protein-protein interactions or the derived distance constraints can be used to verify and refine molecular models. This review focuses on recent advances of "zero-length" cross-linking. Zero-length cross-linking reagents do not add any atoms to the cross-linked species due to the lack of a spacer arm. This provides a major advantage in the form of providing more precise distance constraints as the cross-linkable groups must be within salt bridge distances in order to react. However, identification of cross-linked peptides using these reagents presents unique challenges. We discuss recent efforts by our group to minimize these challenges by using multiple cycles of LC-MS/MS analysis and software specifically developed and optimized for identification of zero-length cross-linked peptides. Representative data utilizing our current protocol are presented and discussed.
Collapse
Affiliation(s)
- Roland F Rivera-Santiago
- The Center for Systems and Computational Biology and Molecular and Cellular Oncogenesis Program, The Wistar Institute, Philadelphia, PA 19104, United States; Biochemistry and Molecular Biophysics Graduate Group, University of Pennsylvania, Philadelphia, PA 19104, United States
| | - Sira Sriswasdi
- The Center for Systems and Computational Biology and Molecular and Cellular Oncogenesis Program, The Wistar Institute, Philadelphia, PA 19104, United States; Department of Biological Sciences, Graduate School of Sciences, The University of Tokyo, Tokyo 113-0032, Japan
| | - Sandra L Harper
- The Center for Systems and Computational Biology and Molecular and Cellular Oncogenesis Program, The Wistar Institute, Philadelphia, PA 19104, United States
| | - David W Speicher
- The Center for Systems and Computational Biology and Molecular and Cellular Oncogenesis Program, The Wistar Institute, Philadelphia, PA 19104, United States; Biochemistry and Molecular Biophysics Graduate Group, University of Pennsylvania, Philadelphia, PA 19104, United States.
| |
Collapse
|