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Cao X, Lu W, Gang Y, Hu B, Wen C. Prx5 of Cristaria plicata has antioxidant function and is regulated by Nrf2/ARE signaling pathway. FISH & SHELLFISH IMMUNOLOGY 2023; 134:108548. [PMID: 36690268 DOI: 10.1016/j.fsi.2023.108548] [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: 12/01/2022] [Revised: 01/09/2023] [Accepted: 01/12/2023] [Indexed: 06/17/2023]
Abstract
Cristaria plicata is one of the more important freshwater pearl bivalves in China, which is susceptible to pathogen infection, and greatly impacts the ability of breeding pearls. Nrf2/ARE signaling pathway and its downstream target gene Prx5 have endogenous antioxidant functions to protect cells from oxidative damage. The full-length cDNA of Prx5 was cloned from C. Plicata, which was 1420 bp, encoding a total of 189 amino acids and had two conserved cysteine residues (Cys78 and Cys179). The amino acid sequence of CpPrx5 was highly similar to Prx5 of other species. Real-time fluorescence quantitative PCR showed that CpPrx5 was distributed in various tissues of mussels, and the highest expression was in hepatopancreas. The expression of CpPrx5 up-regulated in hepatopancreas and gills after LPS, PGN and Poly:I:C stimulation. The recombinant plasmid DE3-PGEX-4T-1-CpPrx5 was expressed in Escherichia coli BL21 and showed antioxidant activity. With the increase of CpPrx5 protein concentration, the superhelical form of DNA was protected. The expression of CpPrx5 was up-regulated after interference CpKeap1 and down-regulated after interference CpNrf2. Gel block assay showed that CpNrf2 and CpMafK proteins blocked CpPrx5 promoter. Subcellular localization showed that CpPrx5 was located in 293T nucleus and cytoplasm and CpMafK was located in 293T nucleus. GST-Pull down verified that CpMafK and CpPrx5 could bind in vitro. These results indicated that Prx5 had antioxidant function and could protects DNA from oxidative damage, and participated in transcriptional regulation by combining with the transcription factor MafK. In addition, MafK could combine with Nrf2 to regulate the downstream target gene Prx5.
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Affiliation(s)
- Xinying Cao
- College of Life Science, Education Ministry Key Laboratory of Poyang Lake Environment and Resource Utilization, Nanchang University, Nanchang, 330031, China
| | - Wuting Lu
- College of Life Science, Education Ministry Key Laboratory of Poyang Lake Environment and Resource Utilization, Nanchang University, Nanchang, 330031, China.
| | - Yang Gang
- College of Life Science, Education Ministry Key Laboratory of Poyang Lake Environment and Resource Utilization, Nanchang University, Nanchang, 330031, China
| | - Baoqing Hu
- College of Life Science, Education Ministry Key Laboratory of Poyang Lake Environment and Resource Utilization, Nanchang University, Nanchang, 330031, China.
| | - Chungen Wen
- College of Life Science, Education Ministry Key Laboratory of Poyang Lake Environment and Resource Utilization, Nanchang University, Nanchang, 330031, China.
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Ellison M, Mittal M, Chaudhuri M, Chaudhuri G, Misra S. The role of the redox/miR-6855-3p/PRDX5A axis in reversing SLUG-mediated BRCA2 silencing in breast cancer cells. Cell Commun Signal 2020; 18:15. [PMID: 31987042 PMCID: PMC6986021 DOI: 10.1186/s12964-019-0493-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Accepted: 12/04/2019] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND We have previously shown that the zinc finger transcription repressor SNAI2 (SLUG) represses tumor suppressor BRCA2-expression in non-dividing cells by binding to the E2-box upstream of the transcription start site. However, it is unclear how proliferating breast cancer (BC) cells that has higher oxidation state, overcome this repression. In this study, we provide insight into the mechanism of de-silencing of BRCA2 gene expression by PRDX5A, which is the longest member of the peroxiredoxin5 family, in proliferating breast cancer cells. METHODS We used cell synchronization and DNA affinity pulldown to analyze PRDX5A binding to the BRCA2 silencer. We used oxidative stress and microRNA (miRNA) treatments to study nuclear localization of PRDX5A and its impact on BRCA2-expression. We validated our findings using mutational, reporter assay, and immunofluorescence analyses. RESULTS Under oxidative stress, proliferating BC cells express PRDX5 isoform A (PRDX5A). In the nucleus, PRDX5A binds to the BRCA2 silencer near the E2-box, displacing SLUG and enhancing BRCA2-expression. Nuclear PRDX5A is translated from the second AUG codon in frame to the first AUG codon in the PRDX5A transcript that retains all exons. Mutation of the first AUG increases nuclear localization of PRDX5A in MDA-MB-231 cells, but mutation of the second AUG decreases it. Increased mitronic hsa-miRNA-6855-3p levels under oxidative stress renders translation from the second AUG preferable. Mutational analysis using reporter assay uncovered a miR-6855-3p binding site between the first and second AUG codon in the PRDX5A transcript. miR-6855-3p mimic increases accumulation of nuclear PRDX5A and inhibits reporter gene translation. CONCLUSION Oxidative stress increases miR-6855-3p expression and binding to the inter-AUG sequence of the PRDX5A transcript, promoting translation of nuclear PRDX5A. Nuclear PRDX5A relieves SLUG-mediated BRCA2 silencing, resulting in increased BRCA2-expression.
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Affiliation(s)
- Marshall Ellison
- Department of Microbiology, Immunology, and Physiology, Meharry Medical College, Nashville, TN, 37208, USA
| | - Mukul Mittal
- Department of Microbiology, Immunology, and Physiology, Meharry Medical College, Nashville, TN, 37208, USA
| | - Minu Chaudhuri
- Department of Microbiology, Immunology, and Physiology, Meharry Medical College, Nashville, TN, 37208, USA
| | - Gautam Chaudhuri
- Department of Microbiology, Immunology, and Physiology, Meharry Medical College, Nashville, TN, 37208, USA
| | - Smita Misra
- School of Graduate Studies and Research, Meharry Medical College, Nashville, TN, 37208, USA. .,Center for Women's Health Research (CWHR), Meharry Medical College, Nashville, TN, 37208, USA.
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Peroxiredoxin 5 Silencing Sensitizes Dopaminergic Neuronal Cells to Rotenone via DNA Damage-Triggered ATM/p53/PUMA Signaling-Mediated Apoptosis. Cells 2019; 9:cells9010022. [PMID: 31861721 PMCID: PMC7016837 DOI: 10.3390/cells9010022] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 12/16/2019] [Accepted: 12/17/2019] [Indexed: 12/11/2022] Open
Abstract
Peroxiredoxins (Prxs) are a family of thioredoxin peroxidases. Accumulating evidence suggests that changes in the expression of Prxs may be involved in neurodegenerative diseases pathology. However, the expression and function of Prxs in Parkinson’s disease (PD) remains unclear. Here, we showed that Prx5 was the most downregulated of the six Prx subtypes in dopaminergic (DA) neurons in rotenone-induced cellular and rat models of PD, suggesting possible roles in regulating their survival. Depletion of Prx5 sensitized SH-SY5Y DA neuronal cells to rotenone-induced apoptosis. The extent of mitochondrial membrane potential collapse, cytochrome c release, and caspase activation was increased by Prx5 loss. Furthermore, Prx5 knockdown enhanced the induction of PUMA by rotenone through a p53-dependent mechanism. Using RNA interference approaches, we demonstrated that the p53/PUMA signaling was essential for Prx5 silencing-exacerbated mitochondria-driven apoptosis. Additionally, downregulation of Prx5 augmented rotenone-induced DNA damage manifested as induction of phosphorylated histone H2AX (γ-H2AX) and activation of ataxia telangiectasia mutated (ATM) kinase. The pharmacological inactivation of ATM revealed that ATM was integral to p53 activation by DNA damage. These findings provided a novel link between Prx5 and DNA damage-triggered ATM/p53/PUMA signaling in a rotenone-induced PD model. Thus, Prx5 might play an important role in protection against rotenone-induced DA neurodegeneration.
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Tolomeo AM, Carraro A, Bakiu R, Toppo S, Garofalo F, Pellegrino D, Gerdol M, Ferro D, Place SP, Santovito G. Molecular characterization of novel mitochondrial peroxiredoxins from the Antarctic emerald rockcod and their gene expression in response to environmental warming. Comp Biochem Physiol C Toxicol Pharmacol 2019; 225:108580. [PMID: 31374295 DOI: 10.1016/j.cbpc.2019.108580] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 07/17/2019] [Accepted: 07/26/2019] [Indexed: 02/07/2023]
Abstract
In the present study we describe the molecular characterization of the two paralogous mitochondrial peroxiredoxins from Trematomus bernacchii, a teleost that plays a pivotal role in the Antarctic food chain. The two putative amino acid sequences were compared with orthologs from other fish, highlighting a high percentage of identity and similarity with the respective variant, in particular for the residues that are essential for the characteristic peroxidase activity of these enzymes. The temporal expression of Prdx3 and Prdx5 mRNAs in response to short-term thermal stress showed a general upregulation of prdx3, suggesting that this isoform is the most affected by temperature increase. These data, together with the peculiar differences between the molecular structures of the two mitochondrial Prdxs in T. bernacchii as well as in the tropical species Stegastes partitus, suggest an adaptation that allowed these poikilothermic aquatic vertebrates to colonize very different environments, characterized by different temperature ranges.
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Affiliation(s)
- A M Tolomeo
- Department of Women's and Children's Health, University of Padova, Padova, Italy
| | - A Carraro
- Department of Women's and Children's Health, University of Padova, Padova, Italy
| | - R Bakiu
- Department of Aquaculture and Fisheries, Agricultural University of Tirana, Tirana, Albania
| | - S Toppo
- Department of Molecular Medicine, University of Padova, Italy
| | - F Garofalo
- Departmentof of Biology, Ecology and Earth Sciences (B.E.S.T.), University of Calabria, Arcavacata di Rende, Italy
| | - D Pellegrino
- Departmentof of Biology, Ecology and Earth Sciences (B.E.S.T.), University of Calabria, Arcavacata di Rende, Italy
| | - M Gerdol
- Department of Life Sciences, University of Trieste, Trieste, Italy
| | - D Ferro
- Department of Pharmacology, University of Arizona, Tucson, AZ, USA
| | - S P Place
- Department of Biology, Sonoma State University, Rohnert Park, CA, USA
| | - G Santovito
- Department of Biology, University of Padova, Padova, Italy.
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Zhao L. Mitochondrial DNA degradation: A quality control measure for mitochondrial genome maintenance and stress response. Enzymes 2019; 45:311-341. [PMID: 31627882 DOI: 10.1016/bs.enz.2019.08.004] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Mitochondria play a central role in bioenergetics, and fulfill a plethora of functions in cell signaling, programmed cell death, and biosynthesis of key protein cofactors. Mitochondria harbor their own genomic DNA, which encodes protein subunits of the electron transport chain and a full set of transfer and ribosomal RNAs. Mitochondrial DNA (mtDNA) is essential for cellular and organismal functions, and defects in mitochondrial genome maintenance have been implicated in common human diseases and mitochondrial disorders. mtDNA repair and degradation are known pathways to cope with mtDNA damage; however, molecular factors involved in this process have remained unclear. Such knowledge is fundamental to the understanding of mitochondrial genomic maintenance and pathology, because mtDNA degradation may contribute to the etiology of mtDNA depletion syndromes and to the activation of the innate immune response by fragmented mtDNA. This article reviews the current literature regarding the importance of mitochondrial DNA degradation in mtDNA maintenance and stress response, and the recent progress in uncovering molecular factors involved in mtDNA degradation. These factors include key components of the mtDNA replication machinery, such as DNA polymerase γ, helicase Twinkle, and exonuclease MGME1, as well as a major DNA-packaging protein, mitochondrial transcription factor A (TFAM).
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Affiliation(s)
- Linlin Zhao
- Department of Chemistry, University of California, Riverside, Riverside, CA, United States.
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Dumay-Odelot H, Durrieu-Gaillard S, El Ayoubi L, Parrot C, Teichmann M. Contributions of in vitro transcription to the understanding of human RNA polymerase III transcription. Transcription 2015; 5:e27526. [PMID: 25764111 DOI: 10.4161/trns.27526] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Human RNA polymerase III transcribes small untranslated RNAs that contribute to the regulation of essential cellular processes, including transcription, RNA processing and translation. Analysis of this transcription system by in vitro transcription techniques has largely contributed to the discovery of its transcription factors and to the understanding of the regulation of human RNA polymerase III transcription. Here we review some of the key steps that led to the identification of transcription factors and to the definition of minimal promoter sequences for human RNA polymerase III transcription.
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Affiliation(s)
- Hélène Dumay-Odelot
- a INSERM U869; University of Bordeaux; Institut Européen de Chimie et Biologie (IECB); 33607 Pessac, France
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Brooks WH, Renaudineau Y. Epigenetics and autoimmune diseases: the X chromosome-nucleolus nexus. Front Genet 2015; 6:22. [PMID: 25763008 PMCID: PMC4329817 DOI: 10.3389/fgene.2015.00022] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2014] [Accepted: 01/16/2015] [Indexed: 12/18/2022] Open
Abstract
Autoimmune diseases occur more often in females, suggesting a key role for the X chromosome. X chromosome inactivation, a major epigenetic feature in female cells that provides dosage compensation of X-linked genes to avoid overexpression, presents special vulnerabilities that can contribute to the disease process. Disruption of X inactivation can result in loss of dosage compensation with expression from previously sequestered genes, imbalance of gene products, and altered endogenous material out of normal epigenetic context. In addition, the human X has significant differences compared to other species and these differences can contribute to the frequency and intensity of the autoimmune disease in humans as well as the types of autoantigens encountered. Here a link is demonstrated between autoimmune diseases, such as systemic lupus erythematosus, and the X chromosome by discussing cases in which typically non-autoimmune disorders complicated with X chromosome abnormalities also present lupus-like symptoms. The discussion is then extended to the reported spatial and temporal associations of the inactive X chromosome with the nucleolus. When frequent episodes of cellular stress occur, the inactive X chromosome may be disrupted and inadvertently become involved in the nucleolar stress response. Development of autoantigens, many of which are at least transiently components of the nucleolus, is then described. Polyamines, which aid in nucleoprotein complex assembly in the nucleolus, increase further during cell stress, and appear to have an important role in the autoimmune disease process. Autoantigenic endogenous material can potentially be stabilized by polyamines. This presents a new paradigm for autoimmune diseases: that many are antigen-driven and the autoantigens originate from altered endogenous material due to episodes of cellular stress that disrupt epigenetic control. This suggests that epigenetics and the X chromosome are important aspects of autoimmune diseases.
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Affiliation(s)
- Wesley H Brooks
- Department of Chemistry, University of South Florida Tampa, FL, USA
| | - Yves Renaudineau
- Research Unit INSERM ERI29/EA2216, SFR ScinBios, Labex Igo "Immunotherapy Graft, Oncology", Réseau Épigénétique et Réseau Canaux Ioniques du Cancéropole Grand Ouest, European University of Brittany Brest, France ; Laboratory of Immunology and Immunotherapy, Hôpital Morvan Brest, France
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8
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Wan H, Kang T, Zhan S, You H, Zhu F, Lee KS, Zhao H, Jin BR, Li J. Peroxiredoxin 5 from common cutworm (Spodoptera litura) acts as a potent antioxidant enzyme. Comp Biochem Physiol B Biochem Mol Biol 2014; 175:53-61. [DOI: 10.1016/j.cbpb.2014.06.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Revised: 06/24/2014] [Accepted: 06/27/2014] [Indexed: 01/12/2023]
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9
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Dynamic Alu methylation during normal development, aging, and tumorigenesis. BIOMED RESEARCH INTERNATIONAL 2014; 2014:784706. [PMID: 25243180 PMCID: PMC4163490 DOI: 10.1155/2014/784706] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Accepted: 08/16/2014] [Indexed: 12/15/2022]
Abstract
DNA methylation primarily occurs on CpG dinucleotides and plays an important role in transcriptional regulations during tissue development and cell differentiation. Over 25% of CpG dinucleotides in the human genome reside within Alu elements, the most abundant human repeats. The methylation of Alu elements is an important mechanism to suppress Alu transcription and subsequent retrotransposition. Decades of studies revealed that Alu methylation is highly dynamic during early development and aging. Recently, many environmental factors were shown to have a great impact on Alu methylation. In addition, aberrant Alu methylation has been documented to be an early event in many tumors and Alu methylation levels have been associated with tumor aggressiveness. The assessment of the Alu methylation has become an important approach for early diagnosis and/or prognosis of cancer. This review focuses on the dynamic Alu methylation during development, aging, and tumor genesis. The cause and consequence of Alu methylation changes will be discussed.
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11
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Choi HI, Chung KJ, Yang HY, Ren L, Sohn S, Kim PR, Kook MS, Choy HE, Lee TH. Peroxiredoxin V selectively regulates IL-6 production by modulating the Jak2-Stat5 pathway. Free Radic Biol Med 2013; 65:270-279. [PMID: 23831231 DOI: 10.1016/j.freeradbiomed.2013.06.038] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Revised: 05/26/2013] [Accepted: 06/21/2013] [Indexed: 01/23/2023]
Abstract
Mammalian peroxiredoxin V (PrdxV) is a multifunctional protein that protects cells from DNA damage and inhibits stress-induced apoptosis. However, PrdxV is also known to be involved in modulating lipopolysaccharide (LPS)-induced host cell signaling, but its precise role is not fully understood. In this study, we used stably transfected RAW264.7 cells and transiently transfected 293-mTLR4-MD2-CD14 cells expressing wild-type (WT) or mutant (C48S) PrdxV to characterize the function and mechanism of action of PrdxV in LPS-induced immune responses. We found that PrdxV selectively reduces production of interleukin 6 (IL-6) by inhibiting activation of signal transducer and activator of transcription 5 (Stat5) through interaction with Jak2. Notably, this activity of PrdxV was dependent on its catalytic Cys48 residue, but not its peroxidase activity. The binding of to Jak2 effectively inhibited Jak2 phosphorylation, but PrdxV did not act as efficiently as SOCS1 (suppressor of cytokine signaling 1). Our results suggest that PrdxV is a key mediator contributing to the regulation of LPS/TLR4-induced immune responses.
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Affiliation(s)
- Hoon-In Choi
- Dental Science Research Institute and the BK21 Project, Medical Research Center for Biomineralization Disorders, School of Dentistry, Chonnam National University, Gwangju, 500-757, Republic of Korea
| | - Kyoung-Jin Chung
- Dental Science Research Institute and the BK21 Project, Medical Research Center for Biomineralization Disorders, School of Dentistry, Chonnam National University, Gwangju, 500-757, Republic of Korea; Technical University of Dresden, Department of Medicine, Division of Vascular inflammation, 01307 Dresden, Germany
| | - Hee-Young Yang
- Dental Science Research Institute and the BK21 Project, Medical Research Center for Biomineralization Disorders, School of Dentistry, Chonnam National University, Gwangju, 500-757, Republic of Korea
| | - Lina Ren
- Dental Science Research Institute and the BK21 Project, Medical Research Center for Biomineralization Disorders, School of Dentistry, Chonnam National University, Gwangju, 500-757, Republic of Korea
| | - Sungoh Sohn
- Dental Science Research Institute and the BK21 Project, Medical Research Center for Biomineralization Disorders, School of Dentistry, Chonnam National University, Gwangju, 500-757, Republic of Korea
| | - Poo-Reun Kim
- Department of Oral & Maxillofacial Surgery, School of Dentistry, Chonnam National University, Gwangju, 500-757, Republic of Korea
| | - Min-Suk Kook
- Department of Oral & Maxillofacial Surgery, School of Dentistry, Chonnam National University, Gwangju, 500-757, Republic of Korea
| | - Hyon E Choy
- Department of Microbiology and Genome Research Center for Enteropathogenic Bacteria, Chonnam National University Medical School, Gwangju 501-746, Republic of Korea
| | - Tae-Hoon Lee
- Dental Science Research Institute and the BK21 Project, Medical Research Center for Biomineralization Disorders, School of Dentistry, Chonnam National University, Gwangju, 500-757, Republic of Korea.
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12
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Van der Eecken V, Clippe A, Dekoninck S, Goemaere J, Walbrecq G, Van Veldhoven PP, Knoops B. Abolition of peroxiredoxin-5 mitochondrial targeting during canid evolution. PLoS One 2013; 8:e72844. [PMID: 24023783 PMCID: PMC3759418 DOI: 10.1371/journal.pone.0072844] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Accepted: 07/16/2013] [Indexed: 11/19/2022] Open
Abstract
In human, the subcellular targeting of peroxiredoxin-5 (PRDX5), a thioredoxin peroxidase, is dependent on the use of multiple alternative transcription start sites and two alternative in-frame translation initiation sites, which determine whether or not the region encoding a mitochondrial targeting sequence (MTS) is translated. In the present study, the abolition of PRDX5 mitochondrial targeting in dog is highlighted and the molecular mechanism underlying the loss of mitochondrial PRDX5 during evolution is examined. Here, we show that the absence of mitochondrial PRDX5 is generalized among the extant canids and that the first events leading to PRDX5 MTS abolition in canids involve a mutation in the more 5′ translation initiation codon as well as the appearance of a STOP codon. Furthermore, we found that PRDX5 MTS functionality is maintained in giant panda and northern elephant seal, which are phylogenetically closely related to canids. Also, the functional consequences of the restoration of mitochondrial PRDX5 in dog Madin-Darby canine kidney (MDCK) cells were investigated. The restoration of PRDX5 mitochondrial targeting in MDCK cells, instead of protecting, provokes deleterious effects following peroxide exposure independently of its peroxidase activity, indicating that mitochondrial PRDX5 gains cytotoxic properties under acute oxidative stress in MDCK cells. Altogether our results show that, although mitochondrial PRDX5 cytoprotective function against oxidative stress has been clearly demonstrated in human and rodents, PRDX5 targeting to mitochondria has been evolutionary lost in canids. Moreover, restoration of mitochondrial PRDX5 in dog MDCK cells, instead of conferring protection against peroxide exposure, makes them more vulnerable.
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Affiliation(s)
- Valérie Van der Eecken
- Institut des Sciences de la Vie, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - André Clippe
- Institut des Sciences de la Vie, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Sophie Dekoninck
- Institut des Sciences de la Vie, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Julie Goemaere
- Institut des Sciences de la Vie, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Geoffroy Walbrecq
- Institut des Sciences de la Vie, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Paul P. Van Veldhoven
- Department of Cellular and Molecular Medicine, LIPIT, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Bernard Knoops
- Institut des Sciences de la Vie, Université catholique de Louvain, Louvain-la-Neuve, Belgium
- * E-mail:
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Knoops B, Goemaere J, Van der Eecken V, Declercq JP. Peroxiredoxin 5: structure, mechanism, and function of the mammalian atypical 2-Cys peroxiredoxin. Antioxid Redox Signal 2011; 15:817-29. [PMID: 20977338 DOI: 10.1089/ars.2010.3584] [Citation(s) in RCA: 165] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Peroxiredoxin 5 (PRDX5) was the last member to be identified among the six mammalian peroxiredoxins. It is also the unique atypical 2-Cys peroxiredoxin in mammals. Like the other five members, PRDX5 is widely expressed in tissues but differs by its surprisingly large subcellular distribution. In human cells, it has been shown that PRDX5 can be addressed to mitochondria, peroxisomes, the cytosol, and the nucleus. PRDX5 is a peroxidase that can use cytosolic or mitochondrial thioredoxins to reduce alkyl hydroperoxides or peroxynitrite with high rate constants in the 10(6) to 10(7) M(-1)s(-1) range, whereas its reaction with hydrogen peroxide is more modest, in the 10(5) M(-1)s(-1) range. PRDX5 crystal structures confirmed the proposed enzymatic mechanisms based on biochemical data but revealed also some specific unexpected structural features. So far, PRDX5 has been viewed mainly as a cytoprotective antioxidant enzyme acting against endogenous or exogenous peroxide attacks rather than as a redox sensor. Accordingly, overexpression of the enzyme in different subcellular compartments protects cells against death caused by nitro-oxidative stresses, whereas gene silencing makes them more vulnerable. Thus, more than 10 years after its molecular cloning, mammalian PRDX5 appears to be a unique peroxiredoxin exhibiting specific functional and structural features.
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Affiliation(s)
- Bernard Knoops
- Institut des Sciences de Vie, Université catholique de Louvain, Louvain-la-Neuve, Belgium.
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Van der Eecken V, Clippe A, Van Veldhoven PP, Knoops B. Mitochondrial targeting of peroxiredoxin 5 is preserved from annelids to mammals but is absent in pig Sus scrofa domesticus. Mitochondrion 2011; 11:973-81. [PMID: 21763786 DOI: 10.1016/j.mito.2011.06.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2010] [Revised: 05/13/2011] [Accepted: 06/29/2011] [Indexed: 11/19/2022]
Abstract
Peroxiredoxin 5 (PRDX5) is a thioredoxin peroxidase able to reduce hydrogen peroxide, alkyl hydroperoxides and peroxynitrite. In human, PRDX5 was reported to be localized in the cytosol, the mitochondria, the peroxisomes and the nucleus. Mitochondrial localization results from the presence of an N-terminal mitochondrial targeting sequence (MTS). Here, we examined the conservation of mitochondrial localization of PRDX5 in animal species. We found that PRDX5 MTS is present and functional in the annelid lugworm Arenicola marina. Surprisingly, although mitochondrial targeting is well conserved among animals, PRDX5 is missing in mitochondria of domestic pig. Thus, it appears that mitochondrial targeting of PRDX5 may have been lost throughout evolution in animal species, including pig, with unknown functional consequences.
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Affiliation(s)
- Valérie Van der Eecken
- Université catholique de Louvain, Institut des Sciences de la Vie, 4-5 place Croix du Sud, B-1348 Louvain-la-Neuve, Belgium
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Radyuk SN, Rebrin I, Klichko VI, Sohal BH, Michalak K, Benes J, Sohal RS, Orr WC. Mitochondrial peroxiredoxins are critical for the maintenance of redox state and the survival of adult Drosophila. Free Radic Biol Med 2010; 49:1892-902. [PMID: 20869434 PMCID: PMC3005798 DOI: 10.1016/j.freeradbiomed.2010.09.014] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2010] [Revised: 09/02/2010] [Accepted: 09/16/2010] [Indexed: 10/19/2022]
Abstract
Drosophila mitochondria contain two peroxidases, peroxiredoxin 3 (dPrx3) and peroxiredoxin 5 (dPrx5), which together constitute the sole known intramitochondrial mechanism for the catalytic removal of hydrogen and organic peroxides. dPrx3 exists exclusively within mitochondria, whereas dPrx5 is also present in some other intracellular compartments. Levels of these two peroxiredoxins were genetically manipulated, singly and together, in D. melanogaster, for the purpose of understanding their respective functions. Underexpression of dPrx3 by 90-95% had no discernable effect on life span under normal or oxidative stress conditions; the dPrx5 null flies were previously reported to exhibit a 10% shortening of mean life span and an increase in sensitivity to oxidative stress. Flies underexpressing both dPrx3 and dPrx5 showed an 80% decrease in life span, a severe disruption in thiol homeostasis, and a massive induction of apoptosis in the muscle and digestive system tissues. The early mortality in flies underexpressing both peroxiredoxins was partially offset by overexpression of thioredoxin reductase but not mitochondrion-targeted catalase. These results suggest that mitochondrial peroxiredoxins confer specific protection for thioredoxin/glutathione systems, play a critical role in the maintenance of global thiol homeostasis, and prevent the age-associated apoptosis and premature death.
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Affiliation(s)
- Svetlana N. Radyuk
- Department of Biological Sciences, Southern Methodist University, 6501 Airline Rd., Dallas, TX 75275
| | - Igor Rebrin
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, 1985 Zonal Ave., Los Angeles, CA 90089
| | - Vladimir I. Klichko
- Department of Biological Sciences, Southern Methodist University, 6501 Airline Rd., Dallas, TX 75275
| | - Barbara H. Sohal
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, 1985 Zonal Ave., Los Angeles, CA 90089
| | - Katarzyna Michalak
- Department of Biological Sciences, Southern Methodist University, 6501 Airline Rd., Dallas, TX 75275
| | - Judith Benes
- Department of Biological Sciences, Southern Methodist University, 6501 Airline Rd., Dallas, TX 75275
| | - Rajindar S. Sohal
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, 1985 Zonal Ave., Los Angeles, CA 90089
| | - William C. Orr
- Department of Biological Sciences, Southern Methodist University, 6501 Airline Rd., Dallas, TX 75275
- Corresponding author. Department of Biological Sciences, Southern Methodist University, 6501 Airline Rd., Dallas, TX 75275, USA. Phone: +1-214-768-4018. Fax: +1-214-768-3955.
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16
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Yang HY, Kwon J, Cho EJ, Choi HI, Park C, Park HR, Park SH, Chung KJ, Ryoo ZY, Cho KO, Lee TH. Proteomic analysis of protein expression affected by peroxiredoxin V knock-down in hypoxic kidney. J Proteome Res 2010; 9:4003-15. [PMID: 20553050 DOI: 10.1021/pr100190b] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Peroxiredoxin V, an atypical thioredoxin peroxidase, is widely expressed in mammalian tissues. In addition, Prdx V is localized in mitochondria, peroxisome, cytosol, and the nucleus. Prdx V has been reported to protect a wide range of cellular environments as an antioxidant enzyme, and its dysfunctions may be implicated in several diseases, such as cancer, inflammation, and neurodegenerative disease. Identification and relative quantification of proteins affected by Prdx V may help identify novel signaling mechanisms that are important for oxidative stress response. However, the role of Prdx V in the modulation of hypoxia-related cellular response is not studied yet. To examine the function of endogenous Prdx V in hypoxic condition in vivo, we generated a transgenic mouse model with Prdx V siRNA expression controlled by U6 promoter. Of many tissues, the knockdown of Prdx V expression was displayed in the kidney, lung, and liver but not the spleen and skin. We conducted on the basis of nano-UPLC-MS(E) proteomic study to identify the Prdx V-affected protein networks in hypoxic kidneys. In this study, we identified protein networks associated with oxidative stress, fatty acid metabolism, and mitochondrial dysfunction. Our results indicated that Prdx V affected to regulation of kidney homeostasis under hypoxia stress.
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Affiliation(s)
- Hee-Young Yang
- Department of Oral Biochemistry, Dental Science Research Institute, The second Stage of Brain Korea 21 for Dental School, Chonnam National University, Gwangju, Republic of Korea
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17
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Peroxiredoxin 5 confers protection against oxidative stress and apoptosis and also promotes longevity in Drosophila. Biochem J 2009; 419:437-45. [PMID: 19128239 DOI: 10.1042/bj20082003] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Peroxiredoxin 5 is a distinct isoform of the peroxiredoxin gene family. The antioxidative and anti-apoptotic functions of peroxiredoxin 5 have been extensively demonstrated in cell culture experiments. In the present paper, we provide the first functional analysis of peroxiredoxin 5 in a multicellular organism, Drosophila melanogaster. Similar to its mammalian, yeast or human counterparts, dPrx5 (Drosophila peroxiredoxin 5) is expressed in several cellular compartments, including the cytosol, nucleus and the mitochondrion. Global overexpression of dPrx5 in flies increased resistance to oxidative stress and extended their life span by up to 30% under normal conditions. The dprx5(-/-) null flies were comparatively more susceptible to oxidative stress, had higher incidence of apoptosis, and a shortened life span. TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling) analysis revealed that the dprx5(-/-) null mutant had discernible tissue-specific apoptotic patterns, similar to those observed in control flies exposed to paraquat. In addition, apoptosis was particularly notable in oenocytes. During development the dPrx5 levels co-varied with ecdysone pulses, suggesting inter-relationship between ecdystreroids and dPrx5 expression. The importance of dPrx5 for development was further underscored by the embryonic lethal phenotype of progeny derived from the dprx5(-/-) null mutant. Results from the present study suggest that the antioxidant and anti-apoptotic activities of dPrx5 play a critical role in development and aging of the fly.
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18
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Avila PC, Kropotov AV, Krutilina R, Krasnodembskay A, Tomilin NV, Serikov VB. Peroxiredoxin V Contributes to Antioxidant Defense of Lung Epithelial Cells. Lung 2008; 186:103-14. [DOI: 10.1007/s00408-007-9066-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2007] [Accepted: 12/12/2007] [Indexed: 01/05/2023]
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19
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Gogvadze V, Zhivotovsky B. Alteration of mitochondrial function and cell sensitization to death. J Bioenerg Biomembr 2007; 39:23-30. [PMID: 17549639 DOI: 10.1007/s10863-006-9054-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Stimulation of cell death is a powerful instrument in the organism's struggle with cancer. Apoptosis represents one mode of cell death. However, in a variety of tumor cells proapoptotic mechanisms are downregulated, or not properly activated, whereas antiapoptotic mechanisms are upregulated. Mitochondria are known as key players in the regulation of apoptotic pathways. Specifically, permeabilization of the mitochondrial outer membrane and subsequent release of proapoptotic proteins from the intermembrane space are viewed as decisive events in the initiation and/or execution of apoptosis. Disruption of mitochondrial functions by anticancer drugs, which induce oxidative stress, inhibit mitochondrial respiration, or uncouple oxidative phosphorylation, can sensitize mitochondria in these cells and facilitate outer membrane permeabilization.
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Affiliation(s)
- Vladimir Gogvadze
- Institute of Environmental Medicine, Division of Toxicology, Karolinska Institutet, Box 210, SE-171 77 Stockholm, Sweden.
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20
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Kropotov A, Usmanova N, Serikov V, Zhivotovsky B, Tomilin N. Mitochondrial targeting of human peroxiredoxin V protein and regulation of PRDX5 gene expression by nuclear transcription factors controlling biogenesis of mitochondria. FEBS J 2007; 274:5804-14. [PMID: 17937766 DOI: 10.1111/j.1742-4658.2007.06103.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Peroxiredoxin V (PRDX5) is a member of the family of mammalian proteins that neutralize reactive oxygen species. The PRDX5 gene is constitutively expressed at a high level in many human tissues, but functional elements of its promoter responsible for a high basal activity in the absence of oxidative stress have still not been identified. Among predicted binding sites for transcription factors in the human PRDX5 promoter are binding sites for nuclear respiratory factor 1 (NFR-1) and nuclear respiratory factor 2 (also called GABPA), which regulate the biogenesis of mitochondria. We constructed luciferase reporter gene plasmids containing stepwise deletions of the PRDX5 promoter and examined their activities in transient transfections. Our results suggest that basal PRDX5 promoter activity mostly depends on NFR-1 and GABPA sites. The latter, in the PRDX5 promoter, were conserved in the six mammalian genomes analyzed (human, chimpanzee, cow, mouse, rat and dog) and a fraction of human PRDX5 associates with the mitochondrial matrix. We also found that the N-terminal 50 amino acids of the full-length human PRDX5 (24 kDa) translated from its first AUG codon targets this protein exclusively to mitochondria. However, the short form of PRDX5 (17 kDa), translated from its second AUG codon, has cytoplasmic and nuclear localization, which is also typical for endogenously expressed protein. Together, our results indicate that high basal expression of the PRDX5 gene is coordinated with the expression of nuclear genes encoding mitochondrial proteins and that the PRDX5 protein might play a major role in permanent defense against reactive oxygen species produced by mitochondria.
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Affiliation(s)
- Andrey Kropotov
- Institute of Cytology, Russian Academy of Sciences, St Petersburg, Russia
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21
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Pollak N, Niere M, Ziegler M. NAD kinase levels control the NADPH concentration in human cells. J Biol Chem 2007; 282:33562-33571. [PMID: 17855339 DOI: 10.1074/jbc.m704442200] [Citation(s) in RCA: 135] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
NAD kinases (NADKs) are vital, as they generate the cellular NADP pool. As opposed to three compartment-specific isoforms in plants and yeast, only a single NADK has been identified in mammals whose cytoplasmic localization we established by immunocytochemistry. To understand the physiological roles of the human enzyme, we generated and analyzed cell lines stably deficient in or overexpressing NADK. Short hairpin RNA-mediated down-regulation led to similar (about 70%) decrease of both NADK expression, activity, and the NADPH concentration and was accompanied by increased sensitivity toward H(2)O(2). Overexpression of NADK resulted in a 4-5-fold increase in the NADPH, but not NADP(+), concentration, although the recombinant enzyme phosphorylated preferentially NAD(+). Surprisingly, NADK overexpression and the ensuing increase of the NADPH level only moderately enhanced protection against oxidant treatment. Apparently, to maintain the NADPH level for the regeneration of oxidative defense systems human cells depend primarily on NADP-dependent dehydrogenases (which re-reduce NADP(+)), rather than on a net increase of NADP. The stable shifts of the NADPH level in the generated cell lines were also accompanied by alterations in the expression of peroxiredoxin 5 and Nrf2. Because the basal oxygen radical level in the cell lines was only slightly changed, the redox state of NADP may be a major transmitter of oxidative stress.
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Affiliation(s)
- Nadine Pollak
- Department of Molecular Biology, University of Bergen, Thormøhlensgate 55, N-5008 Bergen, Norway
| | - Marc Niere
- Department of Molecular Biology, University of Bergen, Thormøhlensgate 55, N-5008 Bergen, Norway
| | - Mathias Ziegler
- Department of Molecular Biology, University of Bergen, Thormøhlensgate 55, N-5008 Bergen, Norway.
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22
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Nguyên-Nhu NT, Berck J, Clippe A, Duconseille E, Cherif H, Boone C, Van der Eecken V, Bernard A, Banmeyer I, Knoops B. Human peroxiredoxin 5 gene organization, initial characterization of its promoter and identification of alternative forms of mRNA. ACTA ACUST UNITED AC 2007; 1769:472-83. [PMID: 17628720 DOI: 10.1016/j.bbaexp.2007.05.004] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2006] [Revised: 05/16/2007] [Accepted: 05/25/2007] [Indexed: 01/20/2023]
Abstract
Peroxiredoxin 5 (PRDX5) is a mammalian thioredoxin peroxidase ubiquitously expressed in tissues. Its role as antioxidant enzyme has been previously supported in different pathological situations. In this study, we determined the complete human PRDX5 genomic organization and isolated the 5'-flanking region of the gene. Human PRDX5 gene is composed of six exons and five introns similarly to other chordate PRDX5 genes. Several single nucleotide polymorphisms were identified. Six out of them have amino acid substitutions in protein-coding region. Analysis of the 5'-flanking region of human PRDX5 revealed the presence of a TATA-less promoter containing a canonical CpG island and several putative response elements for transcription factors. To analyze the regulatory mechanisms controlling human PRDX5 expression, we characterized the 5'-flanking region by cloning various segments of this region in front of a luciferase reporter sequence. Transfection in HepG2 cells indicate that the 5'-flanking region contains regulatory elements for constitutive expression of human PRDX5. Multiple transcription start sites were also identified by 5'-RACE-PCR in human liver. Moreover, although no corresponding proteins were reported, we present new alternative splicing variants encoded specifically by human PRDX5 gene. The characterization of human PRDX5 gene revealed the complexity of its regulation and a high variability of sequences that might be associated with pathological situations.
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Affiliation(s)
- Nhu Tiên Nguyên-Nhu
- Laboratory of Cell Biology, ISV, Department of Biology, Université catholique de Louvain, Place Croix du Sud 5, B-1348 Louvain-la-Neuve, Belgium
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23
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Krutilina RI, Kropotov AV, Leutenegger C, Serikov VB. Migrating leukocytes are the source of peroxiredoxin V during inflammation in the airways. JOURNAL OF INFLAMMATION-LONDON 2006; 3:13. [PMID: 17020618 PMCID: PMC1601951 DOI: 10.1186/1476-9255-3-13] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2006] [Accepted: 10/04/2006] [Indexed: 11/12/2022]
Abstract
Background We characterized changes in expression of the antioxidant protein Peroxiredoxin V (PRXV) during airway inflammation. Methods Studies in anesthetized rats and mice; PRXV expression determined by Western blot analyses and immunohistochemistry; PRXV m-RNA expression determined by Taq-Man RT-PCR. Results Bacterial lung inflammation did not change expression of PRXV in murine epithelia but produced massive influx of leukocytes highly expressing PRXV. Endotoxin and f-MLP induced leukocyte migration in rat trachea but did not change mRNA levels and PRXV protein expression in tracheal epithelial cells. In primary airway cell culture (cow), alveolar epithelial cells A549, or co-culture of A549 with murine macrophages RAW264.7, exposure to live bacteria increased expression of PRXV, which required serum. PRXV was secreted in vitro by epithelial and immune cells. Conclusion Inflammation increased expression of PRXV in airways by at least 2 mechanisms: cell population shift by massive influx of leukocytes expressing PRXV, and moderate post-transcriptional up-regulation of PRXV in epithelial cells.
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Affiliation(s)
- Raisa I Krutilina
- Children's Hospital Oakland Research Institute, Oakland, CA 94609, USA
| | - Andrei V Kropotov
- Institute of Cytology Russian Academy of Sciences, St. Petersburg, 194021, Russia
- Children's Hospital Oakland Research Institute, Oakland, CA 94609, USA
| | - Christian Leutenegger
- University of California, Davis, Davis, CA 95616, USA
- Children's Hospital Oakland Research Institute, Oakland, CA 94609, USA
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24
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Kropotov A, Serikov V, Suh J, Smirnova A, Bashkirov V, Zhivotovsky B, Tomilin N. Constitutive expression of the human peroxiredoxin V gene contributes to protection of the genome from oxidative DNA lesions and to suppression of transcription of noncoding DNA. FEBS J 2006; 273:2607-17. [PMID: 16817890 DOI: 10.1111/j.1742-4658.2006.05265.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Peroxiredoxins belong to a family of antioxidant proteins that neutralize reactive oxygen species. One member of this family, peroxiredoxin I (PRDX1), suppresses DNA oxidation. Peroxiredoxin V (PRDX5) has been cloned as a transcriptional corepressor, as a peroxisomal/mitochondrial antioxidant protein, and as an inhibitor of p53-dependent apoptosis. Promoters of mammalian PRDX5 genes contain clusters of antioxidant response elements, which can bind the transcription factor NRF2. However, we found that expression of the human PRDX5 gene in situ was not stimulated by the oxidative agent menadione. Silencing of the NRF2 gene in the absence of oxidative stress by specific siRNA did not decrease PRDX5 protein concentration. We also constructed clones of human lung epithelial cells A549 with siRNA-mediated knockdown of the PRDX5 gene. This led to a significant increase in 8-oxoguanine formation in cell DNA. In the PRDX5 knockdown clone, an increase in transcripts containing sequences of alpha-satellite and satellite III DNAs was also detected, suggesting that this protein may be required for silencing of heterochromatin. Together, these results suggest that constitutively expressed PRDX5 gene plays an important role in protecting the genome against oxidation and may also be involved in the control of transcription of noncoding DNA.
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25
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Kropotov A, Gogvadze V, Shupliakov O, Tomilin N, Serikov VB, Tomilin NV, Zhivotovsky B. Peroxiredoxin V is essential for protection against apoptosis in human lung carcinoma cells. Exp Cell Res 2006; 312:2806-15. [PMID: 16781710 DOI: 10.1016/j.yexcr.2006.05.006] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2006] [Revised: 05/06/2006] [Accepted: 05/12/2006] [Indexed: 10/24/2022]
Abstract
Sensitivity of tumor cells to treatment with anticancer drugs depends on expression and function of antiapoptotic and antioxidant proteins. The goal of our study was to determine the functional role of the novel antioxidant protein Peroxiredoxin V (PrxV), in protection of human lung carcinoma cell lines against apoptosis. Analysis of expression of PrxV in multiple lung carcinoma cell lines revealed a positive correlation between the expression of PrxV and radioresistance in vitro. Clones of the lung carcinoma cells U1810 with down-regulated expression of PrxV, or with its impaired enzymatic function (expression of redox-negative PrxV), demonstrated increased sensitivity to treatment with anticancer drugs etoposide and adriamycin. Pre-treatment of these clones with antioxidant N-acetyl-cysteine did not change their sensitivity to adriamycin, suggesting the involvement of a non-redox activity of PrxV. Expression of the redox-negative PrxV mainly affected the mitochondrial pathway of apoptosis, as assessed by cytochrome c release assay. Impairment of the PrxV enzymatic function also affected transmembrane potential and calcium loading capacity of mitochondria, as well as mitochondrial morphology. Altogether, these findings suggest that PrxV is a multifunctional protein, which is essential for protection against apoptosis induced by anticancer drugs.
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Affiliation(s)
- Andrey Kropotov
- Children's Hospital Oakland Research Institute, Oakland, CA 94609, USA.
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26
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Serikov VB, Leutenegger C, Krutilina R, Kropotov A, Pleskach N, Suh JH, Tomilin NV. Cigarette smoke extract inhibits expression of peroxiredoxin V and increases airway epithelial permeability. Inhal Toxicol 2006; 18:79-92. [PMID: 16326404 DOI: 10.1080/08958370500282506] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Inhaled cigarette smoke induces oxidative stress in the epithelium of airways. Peroxiredoxin V (PRXV) is a potent antioxidant protein, highly expressed in cells of the airway epithelium. The goal of our study was to determine whether cigarette smoke extract (CSE) influenced expression of this protein in airway epithelia in vivo and in vitro. In Sprague-Dawley rats, we determined effects of CSE on airway epithelial permeability, mRNA levels and expression of PRXV protein. Exposure of isolated tracheal segment in vitro to 20% CSE for 4 h resulted in development of increased permeability to albumin, significantly reduced mRNA levels for PRXV, and reduced amounts of PRXV protein in the epithelium. In cultures of the airway epithelial cell lines (Calu-3, JME), primary airway cell culture (cow), and alveolar epithelial cells A549, CSE also significantly decreased transepithelial electrical resistance and expression of PRXV protein, and induced glutathione and protein oxidation. To demonstrate functional importance of PRXV, we exposed clones of HeLa cells with siRNA-downregulated PRXV to hydrogen peroxide, which resulted in increased rate of cell death and protein oxidation. CSE directly downregulates expression of functionally important antioxidant enzyme PRXV in the epithelial cells of airways, which represents one pathophysiological mechanism of cigarette smoke toxicity.
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Affiliation(s)
- Vladimir B Serikov
- Children's Hospital Oakland Research Institute, Oakland, California 94609, USA.
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27
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Abstract
There are clear theoretical reasons and many well-documented examples which show that repetitive, DNA is essential for genome function. Generic repeated signals in the DNA are necessary to format expression of unique coding sequence files and to organise additional functions essential for genome replication and accurate transmission to progeny cells. Repetitive DNA sequence elements are also fundamental to the cooperative molecular interactions forming nucleoprotein complexes. Here, we review the surprising abundance of repetitive DNA in many genomes, describe its structural diversity, and discuss dozens of cases where the functional importance of repetitive elements has been studied in molecular detail. In particular, the fact that repeat elements serve either as initiators or boundaries for heterochromatin domains and provide a significant fraction of scaffolding/matrix attachment regions (S/MARs) suggests that the repetitive component of the genome plays a major architectonic role in higher order physical structuring. Employing an information science model, the 'functionalist' perspective on repetitive DNA leads to new ways of thinking about the systemic organisation of cellular genomes and provides several novel possibilities involving repeat elements in evolutionarily significant genome reorganisation. These ideas may facilitate the interpretation of comparisons between sequenced genomes, where the repetitive DNA component is often greater than the coding sequence component.
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Affiliation(s)
- James A Shapiro
- Department of Biochemistry and Molecular Biology, University of Chicago, 920 E. 58th Street, Chicago, IL 60637, USA.
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28
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Kulski JK, Dunn DS. Polymorphic Alu insertions within the Major Histocompatibility Complex class I genomic region: a brief review. Cytogenet Genome Res 2005; 110:193-202. [PMID: 16093672 DOI: 10.1159/000084952] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2003] [Accepted: 10/21/2003] [Indexed: 11/19/2022] Open
Abstract
Most polymorphic Alu insertions (POALINs) belong to a subgroup of the Alu multicopy retrotransposon family of short interspersed nucleotide elements (SINEs) that are categorized as AluYb8 and AluYa5. The number of AluYb8/AluYa5 members (approximately 4,492 copies) is significantly less than the approximately one million fixed Alu copies per human genome. We have studied the presence of POALINs within the Major Histocompatibility Complex (MHC) class I region on the short arm of chromosome 6 (6p21.3) because this region has a high gene density, many genes with immune system functions, large sequence variations and diversity, duplications and redundancy, and a strong association with more than 100 different diseases. Since little is known about POALINs within the MHC genomic region, we undertook to identify some of the members of the AluYb8/AluYa5 subfamily and to study their frequency of distribution and genetic characteristics in different populations. As a result of our comparative genomic analyses, we identified the insertion sites for five POALINs distributed within the MHC class I region. This brief review outlines the locations of the insertions and sequence features of the five MHC POALINs, their single site and haplotype frequencies in different geographic populations, and their association with different HLA class I genes and disease. We show that the MHC POALINs have a potential value as lineage and linkage markers for the study of human population genetics, disease associations, genomic diversity and evolution.
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Affiliation(s)
- J K Kulski
- Centre for Bioinformatics and Biological Computing, School of Information Technology, Murdoch University, Murdoch, Western Australia.
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29
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Abstract
Peroxiredoxin 5 (PRDX5) is a newly discovered thioredoxin peroxidase able to reduce peroxides that is implicated in antioxidant protective mechanisms. We report here its expression in the human thyroid gland. Twenty-seven human thyroid specimens were examined by immunohistochemistry. They included six normal thyroid tissues, five multinodular goiters, nine hot nodules, two Hürthle cell adenomas, and five thyroids from patients with Graves' disease. In the control tissue, PRDX5 expression was heterogeneous, being stronger in cubical functionally active follicular cells than in flat quiescent thyrocytes. It was diffuse in the cytoplasm, occasionally localized in inclusions that most likely corresponded to mitochondria. This feature was particularly marked in the Hürthle cell adenoma case. In multinodular goiters, hot nodules, and Graves' thyroids, the cytosolic labeling was enhanced compared to the control tissue and a signal was also detected in few nuclei. To determine whether the level of expression was different between multinodular goiters and hyperthyroid Graves' thyroids, PRDX5 immunoblotting was performed in these two respective tissues. We observed that PRDX5 expression was higher in the thyroid gland of patients with Graves' disease compared to multinodular goiters. In conclusion, our data show that PRDX5 is expressed in the thyroid gland where it could act as antioxidant. The level of expression is directly correlated with the functional status of epithelial cells, being higher in multinodular goiters, and even more pronounced in hyperthyroid tissues, such as Graves' disease.
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Affiliation(s)
- A-C Gérard
- Unité de Morphologie Expérimentale, B-1200, Bruxelles, Belgium
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30
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Tripathi MK, Misra S, Khedkar SV, Hamilton N, Irvin-Wilson C, Sharan C, Sealy L, Chaudhuri G. Regulation of BRCA2 gene expression by the SLUG repressor protein in human breast cells. J Biol Chem 2005; 280:17163-71. [PMID: 15734731 PMCID: PMC3092429 DOI: 10.1074/jbc.m501375200] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The expression of the breast cancer susceptibility protein BRCA2 is highly regulated in human breast, ovary, and pancreatic cells. BRCA2 is not expressed in the non-dividing cells, and expression is cell cycle stage-dependent and is elevated in the sporadic cancer cells. Mutational analysis of the upstream sequence of the human BRCA2 gene revealed an E2-box-containing silencer at the -701 to -921 position. The E2-box is essential for the cell-cycle stage-dependent activity of the silencer. We affinity-purified a 29-kDa silencer-binding protein (SBP) from the nuclear extracts of human breast cells BT-549 and MDA-MB-231. We explored whether the E2-box-binding repressor protein SLUG, which is of similar molecular size, is involved in the silencing process. Supershift assay with the purified SBP and anti-SLUG antibody revealed the identity of the SBP as SLUG. We found that silencer is inactive in the human breast cancer cells such as MDA-MB-468 and MCF-7 that do not express SLUG, further suggesting the involvement of SLUG in the BRCA2 gene silencing. Inducible expression of human SLUG in the dividing MDA-MB-468 cells reduced BRCA2 RNA levels with the activation of the silencer. Furthermore, small interfering RNA-mediated knockdown of SLUG mRNA in the BT-549 cells caused inhibition of the silencer function. Chromatin immunoprecipitation assays suggested that SLUG mediates its action by recruiting C-terminal-binding protein-1 (CtBP-1) and histone deacetylase-1 (HDAC-1) at the silencer E2-box. The general HDAC inhibitor, trichostatin A, inhibited the SLUG-mediated regulation of the silencer function. It thus appears that SLUG is a negative regulator for BRCA2 gene expression.
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MESH Headings
- Acetylation
- Alcohol Oxidoreductases
- BRCA2 Protein/biosynthesis
- BRCA2 Protein/genetics
- Base Sequence
- Blotting, Northern
- Blotting, Western
- Breast Neoplasms/genetics
- Breast Neoplasms/metabolism
- Breast Neoplasms/pathology
- Cell Line, Tumor
- Cell Nucleus/metabolism
- Chromatin Immunoprecipitation
- DNA/metabolism
- DNA Mutational Analysis
- DNA-Binding Proteins/metabolism
- Gene Expression Regulation, Neoplastic
- Gene Silencing
- Histone Deacetylases/metabolism
- Histones/chemistry
- Humans
- Models, Genetic
- Molecular Sequence Data
- Mutagenesis, Site-Directed
- Phosphoproteins/metabolism
- Promoter Regions, Genetic
- Protein Binding
- Protein Conformation
- Protein Structure, Tertiary
- RNA, Messenger/metabolism
- RNA, Small Interfering/metabolism
- Recombinant Proteins/chemistry
- Reverse Transcriptase Polymerase Chain Reaction
- Snail Family Transcription Factors
- Transcription Factors/metabolism
- Transfection
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Affiliation(s)
- Manish K. Tripathi
- Division of Cancer Biology, Department of Biomedical Sciences, Meharry Medical College, Vanderbilt University Medical Center, Nashville, Tennessee 37208
| | - Smita Misra
- Division of Cancer Biology, Department of Biomedical Sciences, Meharry Medical College, Vanderbilt University Medical Center, Nashville, Tennessee 37208
| | - Sheetal V. Khedkar
- Division of Cancer Biology, Department of Biomedical Sciences, Meharry Medical College, Vanderbilt University Medical Center, Nashville, Tennessee 37208
| | - Nalo Hamilton
- Division of Cancer Biology, Department of Biomedical Sciences, Meharry Medical College, Vanderbilt University Medical Center, Nashville, Tennessee 37208
| | - Charletha Irvin-Wilson
- Division of Cancer Biology, Department of Biomedical Sciences, Meharry Medical College, Vanderbilt University Medical Center, Nashville, Tennessee 37208
| | - Chakradhari Sharan
- Division of Cancer Biology, Department of Biomedical Sciences, Meharry Medical College, Vanderbilt University Medical Center, Nashville, Tennessee 37208
| | - Linda Sealy
- Department of Molecular Physiology and Biophysics, Vanderbilt University Medical Center, Nashville, Tennessee 37208
| | - Gautam Chaudhuri
- Division of Cancer Biology, Department of Biomedical Sciences, Meharry Medical College, Vanderbilt University Medical Center, Nashville, Tennessee 37208
- To whom correspondence should be addressed: Div, of Cancer Biology, Dept. of Biomedical Sciences, Meharry Medical College, 1005 D. B. Todd, Jr. Blvd., Nashville, TN 37208. Tel.: 615-327-6499; Fax 615-327-5559;
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31
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Serikov VB, Popov BV, Kropotov AV, Tomilin NV. BM-derived cells restore expression of peroxiredoxin V in the airways following acute naphthalene injury in mice. Cytotherapy 2005; 7:483-93. [PMID: 16306010 DOI: 10.1080/14653240500361012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
BACKGROUND Naphthalene-induced respiratory tract toxicity in mice is characterized by specific and rapid loss of the Clara cell population, which is restored only after several days. The sources of restoration of this cell population remain unclear. We investigated whether BM-derived cells participated in the process of epithelial restoration following naphthalene toxicity compared with bacterial infection. We further investigated the role of BM-derived cells in restoration of expression of peroxiredoxin V (PRXV), one of the major proteins of antioxidant defense, specifically expressed in the bronchial epithelium. METHODS We transplanted GFP-tagged BM cells into 5 Gy-irradiated C57BL/6 recipients. Following 1 month of recovery, experimental animals were subjected to 250 mg/kg naphthalene i.p. An additional group of animals received intratracheal instillation of Escherichia coli to induce acute bacterial inflammation. Animals were killed at 1-12 days after naphthalene and analyzed immunohistochemically. RESULTS Recipients' cells of bronchial epithelium demonstrated significantly reduced levels of PRXV expression following naphthalene. In animals with acute bacterial inflammation, PRXV levels were not reduced in epithelium and participation of BM-derived cells in epithelial restoration was minimal. Following naphthalene, GFP(+) cells were present in large numbers in lung parenchyma and epithelium of conducting airways starting at 1 day following injury. GFP(+) progeny of BM cells was the major source of PRXV in the epithelium. DISCUSSION These data suggest that BM-derived cells may provide a source of antioxidant protection of airways by expression of PRXV in a model of acute epithelial respiratory tract toxicity.
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Affiliation(s)
- V B Serikov
- Children's Hospital Oakland Research Institute, 5700 M. L. King Jr Way, California 94609, USA
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32
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Kropotov AV, Grudinkin PS, Pleskach NM, Gavrilov BA, Tomilin NV, Zhivotovsky B. Downregulation of peroxiredoxin V stimulates formation of etoposide-induced double-strand DNA breaks. FEBS Lett 2004; 572:75-9. [PMID: 15304327 DOI: 10.1016/j.febslet.2004.07.011] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2004] [Revised: 07/08/2004] [Accepted: 07/08/2004] [Indexed: 01/17/2023]
Abstract
Antioxidant protein Peroxiredoxin V (PrxV) is located in mitochondria and peroxisomes but is also present in the nucleus. Here, we show that nuclear PrxV associates with coilin-containing bodies suggesting possible interaction of this protein with transcription complexes. We also studied etoposide-induced phosphorylation of histone H2AX (gamma-H2AX) in human cells in which PrxV activity was downregulated (knockdown, KD-clones) or compromised by overexpression of redox-negative (RD) protein. In KD clones, but not in RD-clones, formation of etoposide-induced gamma-H2AX was increased, indicating that PrxV inhibits conversion of topoisomerase II cleavage complexes into double-strand DNA breaks but this inhibition is not caused by its antioxidant activity.
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Affiliation(s)
- Andrei V Kropotov
- Institute of Cytology, Russian Academy of Sciences, Tikchoretskii Av.4, 194064 St. Petersburg, Russia
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33
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Yuan J, Murrell GAC, Trickett A, Landtmeters M, Knoops B, Wang MX. Overexpression of antioxidant enzyme peroxiredoxin 5 protects human tendon cells against apoptosis and loss of cellular function during oxidative stress. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2004; 1693:37-45. [PMID: 15276323 DOI: 10.1016/j.bbamcr.2004.04.006] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2003] [Revised: 03/22/2004] [Accepted: 04/21/2004] [Indexed: 10/26/2022]
Abstract
Oxidative stress and apoptosis are implicated in tendon degeneration. Peroxiredoxin 5 (PRDX5) is a novel thioredoxin peroxidase recently identified in mammals, participating directly in eliminating hydrogen peroxide (H(2)O(2)) and neutralizing other reactive oxygen species (ROS). We have previously reported that PRDX5 is upregulated in degenerative human tendon. However, the effects of this upregulation on human tendon cell function remain unknown, in particular, with regards to oxidative stress conditions. Here we report that exposure of human tendon cells to 50 microM H(2)O(2) for 24 h (in vitro oxidative stress) caused a significant increase in the percentage of apoptotic cells (P<0.05) as assessed by flow cytometric analysis of Annexin V binding, accompanied by increased PRXD5 mRNA and protein expression. Overexpression of PRDX5 in human tendon cells via transfection inhibited H(2)O(2)-induced tendon cell apoptosis by 46% (P<0.05), and prevented the decrease in tendon cell collagen synthesis which occurs under H(2)O(2) challenge, although the decrease in collagen synthesis was small. Results from our study indicate that the antioxidant enzyme PRDX5 plays a protective role in human tendon cells against oxidative stress by reducing apoptosis and maintaining collagen synthesis.
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Affiliation(s)
- Jun Yuan
- Orthopaedic Research Institute, St. George Hospital Campus, 4-10 South Street, University of New South Wales, Sydney, NSW 2217, Australia
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34
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Evrard C, Capron A, Marchand C, Clippe A, Wattiez R, Soumillion P, Knoops B, Declercq JP. Crystal structure of a dimeric oxidized form of human peroxiredoxin 5. J Mol Biol 2004; 337:1079-90. [PMID: 15046979 DOI: 10.1016/j.jmb.2004.02.017] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2003] [Revised: 01/27/2004] [Accepted: 02/04/2004] [Indexed: 12/25/2022]
Abstract
Peroxiredoxin 5 is the last discovered mammalian member of an ubiquitous family of peroxidases widely distributed among prokaryotes and eukaryotes. Mammalian peroxiredoxin 5 has been recently classified as an atypical 2-Cys peroxiredoxin due to the presence of a conserved peroxidatic N-terminal cysteine (Cys47) and an unconserved resolving C-terminal cysteine residue (Cys151) forming an intramolecular disulfide intermediate in the oxidized enzyme. We have recently reported the crystal structure of human peroxiredoxin 5 in its reduced form. Here, a new crystal form of human peroxiredoxin 5 is described at 2.0 A resolution. The asymmetric unit contains three polypeptide chains. Surprisingly, beside two reduced chains, the third one is oxidized although the enzyme was crystallized under initial reducing conditions in the presence of 1 mM 1,4-dithio-dl-threitol. The oxidized polypeptide chain forms an homodimer with a symmetry-related one through intermolecular disulfide bonds between Cys47 and Cys151. The formation of these disulfide bonds is accompanied by the partial unwinding of the N-terminal parts of the alpha2 helix, which, in the reduced form, contains the peroxidatic Cys47 and the alpha6 helix, which is sequentially close to the resolving residue Cys151. In each monomer of the oxidized chain, the C-terminal part including the alpha6 helix is completely reorganized and is isolated from the rest of the protein on an extended arm. In the oxidized dimer, the arm belonging to the first monomer now appears at the surface of the second subunit and vice versa.
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Affiliation(s)
- Christine Evrard
- Unit of Structural Chemistry (CSTR), Université catholique de Louvain, 1 place Louis Pasteur, B-1348 Louvain-la-Neuve, Belgium
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35
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Oei SL, Babich VS, Kazakov VI, Usmanova NM, Kropotov AV, Tomilin NV. Clusters of regulatory signals for RNA polymerase II transcription associated with Alu family repeats and CpG islands in human promoters. Genomics 2004; 83:873-82. [PMID: 15081116 DOI: 10.1016/j.ygeno.2003.11.001] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2003] [Accepted: 11/07/2003] [Indexed: 10/26/2022]
Abstract
Primate genomes contain a very large number of short interspersed GC-rich repeats of the Alu family, which are abundant in introns and intergenic spacers but also present in 5' flanking regions of genes enriched in binding motifs (BMs) for transcription factors and frequently containing CpG islands. Here we studied whether CpG islands located in promoters of human genes overlap with Alu repeats and with clusters of BMs for the zinc-finger transcription factors Sp1, estrogen receptor alpha, and YY1. The presence of estrogen-response elements in Alu was shown earlier and here we confirm the presence in the consensus Alu sequence of the binding sites for Sp1 and YY1. Analyzing >5000 promoters from the two databases we found that Alu sequences are underrepresented in promoters compared to introns and that approximately 4% of CpG islands located within the -1000 to +200 segments of human promoters overlap with Alu repeats. Although this fraction was found to be lower for proximal segments of promoters (-500 to +100), our results indicate that a significant number (>1000) of all human genes may be controlled by Alu-associated CpG islands. Analysis of clustering of potential BMs for the indicated transcription factors within some promoters also suggests that the Alu family contributed to the evolution of transcription cis-regulatory modules in the human genome. It is important that among Alu sequences overlapping with CpG islands in promoters a large fraction of members of the old Alu subfamilies is found, suggesting extensive retroposon-assisted regulatory genome evolution during the divergence of the primates.
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Affiliation(s)
- Shiao-Li Oei
- Institute of Biochemistry, Free University of Berlin, Thielallee 63, D-14195, Berlin-Dahlem, Germany
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36
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Banmeyer I, Marchand C, Verhaeghe C, Vucic B, Rees JF, Knoops B. Overexpression of human peroxiredoxin 5 in subcellular compartments of Chinese hamster ovary cells: effects on cytotoxicity and DNA damage caused by peroxides. Free Radic Biol Med 2004; 36:65-77. [PMID: 14732291 DOI: 10.1016/j.freeradbiomed.2003.10.019] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2003] [Revised: 10/22/2003] [Accepted: 10/27/2003] [Indexed: 11/24/2022]
Abstract
Peroxiredoxin 5 is a mammalian thioredoxin peroxidase ubiquitously expressed in tissues. Peroxiredoxin 5 can be intracellularly localized to mitochondria, peroxisomes, the cytosol, and, to a lesser extent, the nucleus. This remarkably wide subcellular distribution compared with the five other mammalian peroxiredoxins prompted us to further investigate the antioxidant protective function of peroxiredoxin 5 in mammalian cells according to its subcellular localization. Chinese hamster ovary cells overexpressing human peroxiredoxin 5 in the cytosol, in mitochondria, or in the nucleus were established by stable transfection. Cells overexpressing peroxiredoxin 5 were exposed for 1 h to low or acute oxidative stress with exogenously added hydrogen peroxide or tert-butylhydroperoxide. Cell protection conferred by peroxiredoxin 5 was evaluated by clonogenicity and lactate dehydrogenase assays. Overexpressing peroxiredoxin 5 in either the cytosolic, mitochondrial, or nuclear compartment significantly reduced cell death, with more effective protection with overexpression of peroxiredoxin 5 in mitochondria, confirming that this organelle is a major target of peroxides. Moreover, we evaluated, with the comet assay, nuclear DNA damage induced by hydrogen peroxide or tert-butylhydroperoxide. Overexpression of peroxiredoxin 5 in the nucleus significantly decreased DNA damage induced by both peroxides. In conclusion, the present study suggests that multiple subcellular targeting of peroxiredoxin 5 in mammalian cells can be implicated in antioxidant protective mechanisms under nonpathological conditions but also during acute oxidative stress caused by peroxides occurring in pathophysiological situations.
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Affiliation(s)
- Ingrid Banmeyer
- Laboratory of Cell Biology, Institut des Sciences de la Vie, Université catholique de Louvain, B-1348 Louvain-La-Neuve, Belgium
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37
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Leyens G, Donnay I, Knoops B. Cloning of bovine peroxiredoxins—gene expression in bovine tissues and amino acid sequence comparison with rat, mouse and primate peroxiredoxins. Comp Biochem Physiol B Biochem Mol Biol 2003; 136:943-55. [PMID: 14662316 DOI: 10.1016/s1096-4959(03)00290-2] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The peroxiredoxin (PRDX) family is a recently identified family of peroxidases found in organisms ranging from bacteria to mammals. In mammals, six PRDX isoforms have been characterized in human (Homo sapiens), rat (Rattus norvegicus) and mouse (Mus musculus). PRDXs are cytosolic, secreted or targeted to organelles such as peroxisomes, mitochondria and the nucleus. Some PRDXs are synthesized as larger precursor proteins with a presequence that is cleaved to produce the mature form. To study the expression of the six PRDXs in bovine (Bos taurus), we first cloned cDNAs coding for PRDX1, PRDX2, PRDX4 and PRDX5. PRDX3 and PRDX6 had previously been cloned and characterized in bovine. The comparison of bovine PRDXs with their rat, mouse and primate orthologues reveals a minimum of 95% similarity of mature proteins. Even though mitochondrial or export signal presequences are normally less conserved, the unprocessed proteins still present a minimum of 84% similarity. Nevertheless, a major divergence lies at the N-terminus of bovine PRDX2, where a Cys-Val-Cys motif was identified. The expression of the six PRDXs in 22 bovine tissues has been studied by RT-PCR. Our results point out the ubiquity of the different PRDX transcripts in bovine tissues. The important conservation of the different PRDXs, the multiple processes they have been associated with, as well as the ubiquity of all the members of the family analyzed in this study for the first time altogether, suggest that they play a major role in the basal metabolism of mammalian cells.
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Affiliation(s)
- Gregory Leyens
- Unité des Sciences vétérinaires, Institut des Sciences de la Vie, Université catholique de Louvain, Place Croix du Sud 5, B-1348 Louvain-la-Neuve, Belgium.
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38
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Tiên Nguyên-nhu N, Knoops B. Mitochondrial and cytosolic expression of human peroxiredoxin 5 in Saccharomyces cerevisiae protect yeast cells from oxidative stress induced by paraquat. FEBS Lett 2003; 544:148-52. [PMID: 12782306 DOI: 10.1016/s0014-5793(03)00493-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Human peroxiredoxin 5 is a recently discovered mitochondrial, peroxisomal and cytosolic thioredoxin peroxidase able to reduce hydrogen peroxide and alkyl hydroperoxides. To gain insight into peroxiredoxin 5 antioxidant role in cell protection, we investigated the resistance of yeast cells expressing human peroxiredoxin 5 in mitochondria or in the cytosol against oxidative stress induced by paraquat. The herbicide paraquat is a redox active drug known to generate superoxide anions in mitochondria and the cytosol of yeast and mammalian cells leading to the formation of several reactive oxygen species. Here, we report that mitochondrial and cytosolic human peroxiredoxin 5 protect yeast cells from cytotoxicity and lipid peroxidation induced by paraquat.
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Affiliation(s)
- Nhu Tiên Nguyên-nhu
- Laboratory of Cell Biology, ISV, Department of Biology, Université Catholique de Louvain, Place Croix du Sud 5, 1348 Louvain-la-Neuve, Belgium
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Plaisant F, Clippe A, Vander Stricht D, Knoops B, Gressens P. Recombinant peroxiredoxin 5 protects against excitotoxic brain lesions in newborn mice. Free Radic Biol Med 2003; 34:862-72. [PMID: 12654475 DOI: 10.1016/s0891-5849(02)01440-5] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The pathophysiology of brain lesions associated with cerebral palsy is multifactorial and likely involves excess release of glutamate and excess production of free radicals, among other factors. Theoretically, antioxidants could limit the severity of these brain lesions. Peroxiredoxins are a family of peroxidases widely distributed in eukaryotes and prokaryotes. Peroxiredoxin 5 (PRDX5) is a recently discovered mammalian member of this family of antioxidant enzymes that is able to reduce hydrogen peroxide and alkyl hydroperoxides. The present study was designed to examine the neuroprotective effects of recombinant PRDX5 against neonatal excitotoxic challenge in both in vivo and in vitro experiments. For in vivo experiments, mice (postnatal day 5) were injected intraneopallially with ibotenate acting on NMDA and metabotropic receptors, or S-bromowillardiine acting on AMPA-kainate receptors to produce excitotoxic stress and brain lesions. Systemically administered recombinant PRDX5 provided protection against ibotenate-induced excitotoxic stress. Brain lesions of animals given ibotenate and PRDX5 were up to 63% smaller than that given ibotenate alone. However, PRDX5 provided no prevention from lesions induced with S-bromowillardiine. A mutated recombinant PRDX5 that is devoid of peroxidase activity was also tested and showed no protection against lesions induced by either ibotenate or S-bromowillardiine. Two classical antioxidants, N-acetylcysteine and catalase-PEG, provided the same neuroprotective effect as PRDX5. For in vitro experiments, neocortical neurons were exposed to 300 microM NMDA alone, NMDA plus recombinant PRDX5, or NMDA, recombinant PRDX5 and dithiothreitol, a classical electron donor for peroxiredoxins. Recombinant PRDX5 plus dithiothreitol displayed a synergistic neuroprotective effect on NMDA-induced neuronal death. These findings indicate that reactive oxygen species production participates in the formation of NMDA receptor-mediated brain lesions in newborn mice and that antioxidant compounds, such as PRDX5, provide some neuroprotection in these models.
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Affiliation(s)
- Frank Plaisant
- INSERM E 9935 and Service de Neurologie Pédiatrique, Hôpital Robert-Debré, Paris, France
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40
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Abstract
Peroxiredoxins constitute a family of peroxidases that lack prosthetic groups or catalytically active heteroatoms. Instead, their peroxidatic activity is due to a strictly conserved cysteine that is activated within a novel catalytic triad in which the cysteine thiol is coordinated to an arginine and a threonine or serine residue. Donor substrates are thiol compounds which differ between subtypes of peroxiredoxins and species. In pathogenic trypanosomatids that lack heme- or seleno-peroxidases peroxiredoxins have been shown to represent the major devices to detoxify hydroperoxides and an equivalent role may be assumed for other protozoal parasites and many bacterial pathogens. In mammals equipped with more efficient peroxidases the peroxiredoxins appear to be responsible for the redox regulation of diverse metabolic processes. The substantial differences in the cosubstrate requirements of the peroxiredoxins of pathogenic microorganisms and their mammalian host may be exploited to selectively inhibit the antioxidant defense of pathogens. Thereby, the pathogen would be more readily eliminated by the innate immune response of the host's phagocytes.
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Affiliation(s)
- Leopold Flohé
- Department of Biochemistry, Technical University of Braunschweig, Mascheroder Weg 1, D-38124 Braunschweig, Germany.
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41
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Nguyên-nhu NT, Knoops B. Alkyl hydroperoxide reductase 1 protects Saccharomyces cerevisiae against metal ion toxicity and glutathione depletion. Toxicol Lett 2002; 135:219-28. [PMID: 12270680 DOI: 10.1016/s0378-4274(02)00280-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Alkyl hydroperoxide reductase 1 (Ahp1p) is a thioredoxin peroxidase of the peroxiredoxin family expressed by Saccharomyces cerevisiae. Recently, disruption of the AHP1 gene has shown that the gene is not essential for yeast growth on glucose medium but revealed a high sensitivity of null mutants to organic peroxides, suggesting that Ahp1p is an important enzyme implicated in oxidative stress protection in S. cerevisiae. To gain insight into antioxidant enzymatic mechanisms involved in cell protection against metal toxicity and glutathione depletion, we investigated the resistance of S. cerevisiae, in which the AHP1 gene was disrupted, against several metals and diethyl maleate, a glutathione depleting agent. We report that Ahp1p protects yeast against toxicity induced by copper, cobalt, chromium, arsenite, arsenate, mercury, zinc and diethyl maleate, suggesting that Ahp1p plays an important role in S. cerevisiae in the protection against metals possibly by reducing peroxides generated in cells by these compounds.
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Affiliation(s)
- Nhu Tiên Nguyên-nhu
- Laboratory of Cell Biology, Department of Biology, Catholic University of Louvain, Place Croix du Sud, 5, B-1348 Louvain-la-Neuve, Belgium
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42
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Wang MX, Wei A, Yuan J, Trickett A, Knoops B, Murrell GAC. Expression and regulation of peroxiredoxin 5 in human osteoarthritis. FEBS Lett 2002; 531:359-62. [PMID: 12417342 DOI: 10.1016/s0014-5793(02)03511-1] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Reactive oxygen species (ROS) are implicated in the pathogenesis of osteoarthritis (OA). However, little is known about the antioxidant defence system in articular cartilage. We investigated the expression and regulation of peroxiredoxin 5 (PRDX5), a newly discovered thioredoxin peroxidase, in human normal and osteoarthritic cartilage. Our results show that human cartilage constitutively expresses PRDX5. Moreover, the expression is up-regulated in OA. Inflammatory cytokines tumour necrosis factor alpha and interleukin 1 beta contribute to this up-regulation by increasing intracellular ROS production. The present study suggests that PRDX5 may play a protective role against oxidative stress in human cartilage.
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Affiliation(s)
- Min Xia Wang
- Orthopaedic Research Institute, St George Hospital, University of New South Wales, Sydney, NSW, Australia
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43
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Abstract
Present knowledge on peroxiredoxins is reviewed with special emphasis on catalytic principles, specificities and biological function. Peroxiredoxins are low efficiency peroxidases using thiols as reductants. They appear to be fairly promiscuous with respect to the hydroperoxide substrate; the specificities for the donor substrate vary considerably between the subfamilies, comprising GSH, thioredoxin, tryparedoxin and the analogous CXXC motifs in bacterial AhpF proteins. Peroxiredoxins are definitely responsible for antioxidant defense in bacteria (AhpC), yeast (thioredoxin peroxidase) and trypanosomatids (tryparedoxin peroxidase). They are considered to determine virulence of mycobacteria and trypanosomatids. In higher plants they are involved in balancing hydroperoxide production during photosynthesis. In higher animals peroxiredoxins appear to be involved in the redox-regulation of cellular signaling and differentiation, displaying in part opposite effects.
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Affiliation(s)
- Birgit Hofmann
- Department of Biochemistry, Technical University of Braunschweig, Germany
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44
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Declercq JP, Evrard C, Clippe A, Stricht DV, Bernard A, Knoops B. Crystal structure of human peroxiredoxin 5, a novel type of mammalian peroxiredoxin at 1.5 A resolution. J Mol Biol 2001; 311:751-9. [PMID: 11518528 DOI: 10.1006/jmbi.2001.4853] [Citation(s) in RCA: 190] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The peroxiredoxins define an emerging family of peroxidases able to reduce hydrogen peroxide and alkyl hydroperoxides with the use of reducing equivalents derived from thiol-containing donor molecules such as thioredoxin, glutathione, trypanothione and AhpF. Peroxiredoxins have been identified in prokaryotes as well as in eukaryotes. Peroxiredoxin 5 (PRDX5) is a novel type of mammalian thioredoxin peroxidase widely expressed in tissues and located cellularly to mitochondria, peroxisomes and cytosol. Functionally, PRDX5 has been implicated in antioxidant protective mechanisms as well as in signal transduction in cells. We report here the 1.5 A resolution crystal structure of human PRDX5 in its reduced form. The crystal structure reveals that PRDX5 presents a thioredoxin-like domain. Interestingly, the crystal structure shows also that PRDX5 does not form a dimer like other mammalian members of the peroxiredoxin family. In the reduced form of PRDX5, Cys47 and Cys151 are distant of 13.8 A although these two cysteine residues are thought to be involved in peroxide reductase activity by forming an intramolecular disulfide intermediate in the oxidized enzyme. These data suggest that the enzyme would necessitate a conformational change to form a disulfide bond between catalytic Cys47 and Cys151 upon oxidation according to proposed peroxide reduction mechanisms. Moreover, the presence of a benzoate ion, a hydroxyl radical scavenger, was noted close to the active-site pocket. The possible role of benzoate in the antioxidant activity of PRDX5 is discussed.
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Affiliation(s)
- J P Declercq
- Université Catholique de Louvain, Unit of Structural Chemistry (CSTR), 1 place Louis Pasteur, Louvain-la-Neuve, B-1348, Belgium.
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45
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Berggren MI, Husbeck B, Samulitis B, Baker AF, Gallegos A, Powis G. Thioredoxin peroxidase-1 (peroxiredoxin-1) is increased in thioredoxin-1 transfected cells and results in enhanced protection against apoptosis caused by hydrogen peroxide but not by other agents including dexamethasone, etoposide, and doxorubicin. Arch Biochem Biophys 2001; 392:103-9. [PMID: 11469800 DOI: 10.1006/abbi.2001.2435] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Thioredoxin-1 (Trx-1) is a small redox oncoprotein whose expression is increased in a number of human primary cancers where it is associated with aggressive tumor growth, inhibition of apoptosis and decreased patient survival. We report that Trx-1-transfected MCF-7 human breast cancer cells have increased expression of thioredoxin peroxidase-1 (TrxP-1) a peroxiredoxin family member that scavenges H(2)O(2) using Trx-1 as a source of reducing equivalents. Our work shows that TrxP-1 is more effective than selenium-dependent glutathione peroxidase in protecting cells against H(2)O(2) damage. Transfection of mouse WEHI7.2 lymphoma cells with human TrxP-1 or TrxP-2, but not TrxP-4, protects the cells against H(2)O(2) induced apoptosis but does not protect against apoptosis induced by dexamethasone, etoposide, or doxorubicin. The results show that an increase in TrxP-1 expression contributes to the protection against H(2)O(2) induced apoptosis caused by Trx-1, but does not protect against apoptosis induced by other agents.
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Affiliation(s)
- M I Berggren
- Arizona Cancer Center, University of Arizona, Tucson, Arizona, 85724-5024, USA
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46
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Mukhopadhyay SS, Sheikh FG, Gupta P. In vitro binding of cattle PstI SINE with a 33-kDa nuclear protein. Genome 2000; 43:981-7. [PMID: 11195352 DOI: 10.1139/g00-072] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
A PstI family of SINEs (short interspersed elements) has been identified in some of the members of the family Bovidae, for example, cattle, buffalo and goat. In vitro DNA-protein interactions were studied to provide a better understanding of the function of these SINEs in the genome. Use of one such cattle PstI interspersed repeat sequence, as a probe in gel retardation assays, has lead to the identification of a repeat DNA-binding factor PIRBP (PstI interspersed repeat binding protein) from cattle liver nuclear extract. Southwestern analysis with liver nuclear extracts from cattle, goat, and buffalo revealed the presence of a PIRBP-like nuclear factor in all three species belonging to the family Bovidae. Deletion analysis localized the PIRBP binding site to an 80-bp (337-417 bp) region within the cattle PstI sequence. UV crosslinking and Southwestern analyses clearly indicated that PIRBP is a singular, small polypeptide of 33-kDa molecular mass. Homology search of the nucleic acids database revealed that the cattle PstI sequence was associated with many different genes of the family Bovidae, either in the 5' flanking region, 5' locus activating region, 3' UTR or in intervening sequences. The binding of the cattle PstI SINE by PIRBP and its association with the regulatory regions of the genes suggests that it plays an important role in the bovine genome.
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Zhou Y, Kok KH, Chun AC, Wong CM, Wu HW, Lin MC, Fung PC, Kung H, Jin DY. Mouse peroxiredoxin V is a thioredoxin peroxidase that inhibits p53-induced apoptosis. Biochem Biophys Res Commun 2000; 268:921-7. [PMID: 10679306 DOI: 10.1006/bbrc.2000.2231] [Citation(s) in RCA: 136] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have identified human and mouse peroxiredoxin V (Prx-V) by virtue of the sequence homologies to yeast peroxisomal antioxidant enzyme PMP20. Prx-V represents the fifth of the six currently known subfamilies of mammalian peroxiredoxins. It is a novel organellar enzyme that has orthologs in bacteria. Biochemically, Prx-V is a thioredoxin peroxidase. One important aspect of p53 function in mammalian cells involves induction of apoptosis likely mediated by redox. We show that overexpression of Prx-V prevented the p53-dependent generation of reactive oxygen species. Likewise, Prx-V inhibited p53-induced apoptosis. Thus, Prx-V is critically involved in intracellular redox signaling.
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Affiliation(s)
- Y Zhou
- Institute of Molecular Biology, Division of Medical Physics, Department of Medicine, University of Hong Kong, Pokfulam, Hong Kong, China
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Wong CM, Chun AC, Kok KH, Zhou Y, Fung PC, Kung HF, Jeang KT, Jin DY. Characterization of human and mouse peroxiredoxin IV: evidence for inhibition by Prx-IV of epidermal growth factor- and p53-induced reactive oxygen species. Antioxid Redox Signal 2000; 2:507-18. [PMID: 11229364 DOI: 10.1089/15230860050192288] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The aim of this study was to identify and characterize human and mouse Prx-IV. We identified mouse peroxiredoxin IV (Prx-IV) by virtue of sequence homology to its human ortholog previously called AOE372. Mouse Prx-IV conserves an amino-terminal presequence coding for signal peptide. The amino acid sequences of mature mouse and human Prx-IV share 97.5% identity. Phylogenetic analysis demonstrates that Prx-IV is more closely related to Prx-I/-II/-III than to Prx-V/-VI. Previously, we mapped the mouse Prx-IV gene to chromosome X by analyzing two sets of multiloci genetic crosses. Here we performed further comparative analysis of mouse and human Prx-IV genomic loci. Consistent with the mouse results, human Prx-IV gene localized to chromosome Xp22.135-136, in close proximity to SAT and DXS7178. A bacterial artificial chromosome (BAC) clone containing the complete human Prx-IV locus was identified. The size of 7 exons and the sequences of the splice junctions were confirmed by PCR analysis. We conclude that mouse Prx-IV is abundantly expressed in many tissues. However, we could not detect Prx-IV in the conditioned media of NIH-3T3 and Jurkat cells. Mouse Prx-IV was specifically found in the nucleus-excluded region of cultured mouse cells. Intracellularly, overexpression of mouse Prx-IV prevented the production of reactive oxygen species induced by epidermal growth factor or p53. Taken together, mouse Prx-IV is likely a cytoplasmic or organellar peroxiredoxin involved in intracellular redox signaling.
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Affiliation(s)
- C M Wong
- Institute of Molecular Biology, The University of Hong Kong, Pokfulam
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Sharan C, Hamilton NM, Parl AK, Singh PK, Chaudhuri G. Identification and characterization of a transcriptional silencer upstream of the human BRCA2 gene. Biochem Biophys Res Commun 1999; 265:285-90. [PMID: 10558858 PMCID: PMC3100288 DOI: 10.1006/bbrc.1999.1652] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Expression of the breast cancer susceptibility tumor-suppressor protein BRCA2, a protein potentially involved in DNA recombination repair, is tightly regulated throughout development. We have identified a transcriptional silencer at the distal end of the human BRCA2 gene promoter. This silencer is involved in the negative regulation of the expression of this gene in breast cell lines tested but not in HeLa or HepG2 cells. The 221-base-pair silencer region is characterized by a full-length Alu-repeat. Presence of specific BRCA2 silencer-binding proteins in the breast cell extracts indicates the potential regulation of BRCA2 gene expression by these proteins.
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Affiliation(s)
| | | | | | | | - Gautam Chaudhuri
- To whom correspondence should be addressed at Division of Biomedical Sciences, Meharry Medical College, HD West Basic Science Bldg., Room 4220, 1005 D. B. Todd, Jr. Blvd., Nashville, TN 37208. Fax: (615) 327-6072.
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