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Tong T, Zhai PS, Qin X, Zhang Z, Li CW, Guo HY, Ma HL. Nuclear TOP1MT Confers Cisplatin Resistance via Pseudogene in HNSCC. J Dent Res 2024:220345241272017. [PMID: 39382100 DOI: 10.1177/00220345241272017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/10/2024] Open
Abstract
Cisplatin resistance is one of the major causes of treatment failure in head and neck squamous cell carcinoma (HNSCC). There is an urgent need to uncover the underlying mechanism for developing effective treatment strategies. A quantitative proteomics assay was used to identify differential proteins in cisplatin-resistant cells. Mitochondrial topoisomerase I (TOP1MT) localization was determined using laser confocal microscopy and nucleocytoplasmic separation assay. Chromatin immunoprecipitation sequencing, dual-luciferase reporter assay, and RNA immunoprecipitation were used to identify the interaction between pseudogenes, miRNAs, and real genes. In vivo experiments verified the interaction between TOP1MT and pseudogenes on cisplatin resistance. TOP1MT was identified as a driving factor of cisplatin resistance in vitro, in vivo, and in HNSCC patients. Moreover, TOP1MT exceptionally translocated to the nucleus in cisplatin-resistant HNSCC cells in a signal peptide-dependent manner. Nuclear TOP1MT (nTOP1MT) transcriptionally regulated the mitochondrial functional pseudogene MTATP6P1, which bound to miR-137 and miR-491-5p as a competing endogenous RNA (ceRNA) and promoted the expression of MTATP6. An increase in MTATP6 enhanced mitochondrial oxidative phosphorylation (OXPHOS), which conferred cisplatin resistance in HNSCC. Our findings revealed that nTOP1MT transcriptionally activated MTAPT6P1 and increased MTATP6 expression via ceRNA, which facilitated OXPHOS and cisplatin resistance. These results provide novel insight for overcoming cisplatin resistance in HNSCC.
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Affiliation(s)
- T Tong
- Department of Oral and Maxillofacial-Head & Neck Oncology, Shanghai Ninth People's Hospital
- Shanghai Jiao Tong University School of Medicine, PR China
- College of Stomatology, Shanghai Jiao Tong University, PR China
- National Center for Stomatology, PR China
- National Clinical Research Center for Oral Diseases, PR China
- Shanghai Key Laboratory of Stomatology, Shanghai, PR China
- Department of Oral and Maxillofacial Surgery, Shanghai Stomatological Hospital, Fudan University, Shanghai, PR China
- Shanghai Key Laboratory of Craniomaxillofacial Development and Diseases, Fudan University, Shanghai, PR China
| | - P S Zhai
- Department of Oral and Maxillofacial-Head & Neck Oncology, Shanghai Ninth People's Hospital
- Shanghai Jiao Tong University School of Medicine, PR China
- College of Stomatology, Shanghai Jiao Tong University, PR China
- National Center for Stomatology, PR China
- National Clinical Research Center for Oral Diseases, PR China
- Shanghai Key Laboratory of Stomatology, Shanghai, PR China
| | - X Qin
- Department of Oral and Maxillofacial-Head & Neck Oncology, Shanghai Ninth People's Hospital
- Shanghai Jiao Tong University School of Medicine, PR China
- College of Stomatology, Shanghai Jiao Tong University, PR China
- National Center for Stomatology, PR China
- National Clinical Research Center for Oral Diseases, PR China
- Shanghai Key Laboratory of Stomatology, Shanghai, PR China
| | - Z Zhang
- Department of Oral and Maxillofacial-Head & Neck Oncology, Shanghai Ninth People's Hospital
- Shanghai Jiao Tong University School of Medicine, PR China
- College of Stomatology, Shanghai Jiao Tong University, PR China
- National Center for Stomatology, PR China
- National Clinical Research Center for Oral Diseases, PR China
- Shanghai Key Laboratory of Stomatology, Shanghai, PR China
| | - C W Li
- Department of Oral and Maxillofacial-Head & Neck Oncology, Shanghai Ninth People's Hospital
- Shanghai Jiao Tong University School of Medicine, PR China
- College of Stomatology, Shanghai Jiao Tong University, PR China
- National Center for Stomatology, PR China
- National Clinical Research Center for Oral Diseases, PR China
- Shanghai Key Laboratory of Stomatology, Shanghai, PR China
| | - H Y Guo
- Department of Clinical Laboratory, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine
| | - H L Ma
- Department of Oral and Maxillofacial-Head & Neck Oncology, Shanghai Ninth People's Hospital
- Shanghai Jiao Tong University School of Medicine, PR China
- College of Stomatology, Shanghai Jiao Tong University, PR China
- National Center for Stomatology, PR China
- National Clinical Research Center for Oral Diseases, PR China
- Shanghai Key Laboratory of Stomatology, Shanghai, PR China
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Baechler SA, Saha LK, Factor VM, Chitnis C, Dhall A, Becker D, Marquardt JU, Pommier Y. Mitochondrial topoisomerase I (Top1MT) prevents the onset of metabolic dysfunction-associated steatohepatitis (MASH) in mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.09.05.611454. [PMID: 39372760 PMCID: PMC11451593 DOI: 10.1101/2024.09.05.611454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/08/2024]
Abstract
High fat (HF) diet is a major factor in the development of metabolic dysfunction-associated steatotic liver disease (MASLD) and steatohepatis (MASH), and mitochondria have been proposed to play a role in the pathogenesis of HF diet-induced MASH. Because Mitochondrial topoisomerase I (Top1MT) is exclusively present in mitochondria and Top1MT knock-out mice are viable, we were able to assess the role of Top1MT in the development of MASH. We show that after 16 weeks of HF diet, mice lacking Top1MT are prone to the development of severe MASH characterized by liver steatosis, lobular inflammation and hepatocyte damage. Mice lacking Top1MT also show prominent mitochondrial dysfunction, ROS production and mitochondrial DNA (mtDNA) release, accompanied by hepatic inflammation and fibrosis. In summary, our study demonstrates the importance of Top1MT in sustaining hepatocyte functions and suppressing MASH.
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Johnson OD, Paul S, Gutierrez JA, Russell WK, Ward MC. DNA damage-associated protein co-expression network in cardiomyocytes informs on tolerance to genetic variation and disease. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.14.607863. [PMID: 39185220 PMCID: PMC11343126 DOI: 10.1101/2024.08.14.607863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 08/27/2024]
Abstract
Cardiovascular disease (CVD) is associated with both genetic variants and environmental factors. One unifying consequence of the molecular risk factors in CVD is DNA damage, which must be repaired by DNA damage response proteins. However, the impact of DNA damage on global cardiomyocyte protein abundance, and its relationship to CVD risk remains unclear. We therefore treated induced pluripotent stem cell-derived cardiomyocytes with the DNA-damaging agent Doxorubicin (DOX) and a vehicle control, and identified 4,178 proteins that contribute to a network comprising 12 co-expressed modules and 403 hub proteins with high intramodular connectivity. Five modules correlate with DOX and represent distinct biological processes including RNA processing, chromatin regulation and metabolism. DOX-correlated hub proteins are depleted for proteins that vary in expression across individuals due to genetic variation but are enriched for proteins encoded by loss-of-function intolerant genes. While proteins associated with genetic risk for CVD, such as arrhythmia are enriched in specific DOX-correlated modules, DOX-correlated hub proteins are not enriched for known CVD risk proteins. Instead, they are enriched among proteins that physically interact with CVD risk proteins. Our data demonstrate that DNA damage in cardiomyocytes induces diverse effects on biological processes through protein co-expression modules that are relevant for CVD, and that the level of protein connectivity in DNA damage-associated modules influences the tolerance to genetic variation.
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Affiliation(s)
- Omar D. Johnson
- Biochemistry, Cellular and Molecular Biology Graduate Program, University of Texas Medical Branch, Galveston, Texas, USA
- MD-PhD Combined Degree Program, University of Texas Medical Branch, Galveston, Texas, USA
| | - Sayan Paul
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas, USA
| | - Jose A. Gutierrez
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas, USA
| | - William K. Russell
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas, USA
| | - Michelle C. Ward
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas, USA
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Bhasin V, Vakilpour A, Scherrer-Crosbie M. Statins for the Primary Prevention of Anthracycline Cardiotoxicity: A Comprehensive Review. Curr Oncol Rep 2024:10.1007/s11912-024-01579-6. [PMID: 39002055 DOI: 10.1007/s11912-024-01579-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/02/2024] [Indexed: 07/15/2024]
Abstract
PURPOSE OF REVIEW The aim of this review is two-fold: (1) To examine the mechanisms by which statins may protect from anthracycline-induced cardiotoxicity and (2) To provide a comprehensive overview of the existing clinical literature investigating the role of statins for the primary prevention of anthracycline-induced cardiotoxicity. RECENT FINDINGS The underlying cardioprotective mechanisms associated with statins have not been fully elucidated. Key mechanisms related to the inhibition of Ras homologous (Rho) GTPases have been proposed. Data from observational studies has supported the beneficial role of statins for the primary prevention of anthracycline-induced cardiotoxicity. Recently, several randomized controlled trials investigating the role of statins for the primary prevention of anthracycline-induced cardiotoxicity have produced contrasting results. Statins have been associated with a lower risk of cardiac dysfunction in cancer patients receiving anthracyclines. Further investigation with larger randomized control trials and longer follow-up periods are needed to better evaluate the long-term role of statin therapy and identify the subgroups who benefit most from statin therapy.
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Affiliation(s)
- Varun Bhasin
- Division of Cardiovascular Medicine and Thalheimer Center for Cardio-Oncology, Perelman Center for Advanced Medicine and Hospital of the University of Pennsylvania, 3400 Civic Center Boulevard, Philadelphia, PA, USA
| | - Azin Vakilpour
- Division of Cardiovascular Medicine and Thalheimer Center for Cardio-Oncology, Perelman Center for Advanced Medicine and Hospital of the University of Pennsylvania, 3400 Civic Center Boulevard, Philadelphia, PA, USA
| | - Marielle Scherrer-Crosbie
- Division of Cardiovascular Medicine and Thalheimer Center for Cardio-Oncology, Perelman Center for Advanced Medicine and Hospital of the University of Pennsylvania, 3400 Civic Center Boulevard, Philadelphia, PA, USA.
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Bernardino Gomes TM, Vincent AE, Menger KE, Stewart JB, Nicholls TJ. Mechanisms and pathologies of human mitochondrial DNA replication and deletion formation. Biochem J 2024; 481:683-715. [PMID: 38804971 PMCID: PMC11346376 DOI: 10.1042/bcj20230262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2024] [Revised: 05/13/2024] [Accepted: 05/14/2024] [Indexed: 05/29/2024]
Abstract
Human mitochondria possess a multi-copy circular genome, mitochondrial DNA (mtDNA), that is essential for cellular energy metabolism. The number of copies of mtDNA per cell, and their integrity, are maintained by nuclear-encoded mtDNA replication and repair machineries. Aberrant mtDNA replication and mtDNA breakage are believed to cause deletions within mtDNA. The genomic location and breakpoint sequences of these deletions show similar patterns across various inherited and acquired diseases, and are also observed during normal ageing, suggesting a common mechanism of deletion formation. However, an ongoing debate over the mechanism by which mtDNA replicates has made it difficult to develop clear and testable models for how mtDNA rearrangements arise and propagate at a molecular and cellular level. These deletions may impair energy metabolism if present in a high proportion of the mtDNA copies within the cell, and can be seen in primary mitochondrial diseases, either in sporadic cases or caused by autosomal variants in nuclear-encoded mtDNA maintenance genes. These mitochondrial diseases have diverse genetic causes and multiple modes of inheritance, and show notoriously broad clinical heterogeneity with complex tissue specificities, which further makes establishing genotype-phenotype relationships challenging. In this review, we aim to cover our current understanding of how the human mitochondrial genome is replicated, the mechanisms by which mtDNA replication and repair can lead to mtDNA instability in the form of large-scale rearrangements, how rearranged mtDNAs subsequently accumulate within cells, and the pathological consequences when this occurs.
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Affiliation(s)
- Tiago M. Bernardino Gomes
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, U.K
- Wellcome Centre for Mitochondrial Research, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, U.K
- NHS England Highly Specialised Service for Rare Mitochondrial Disorders, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne NE2 4HH, U.K
| | - Amy E. Vincent
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, U.K
- Wellcome Centre for Mitochondrial Research, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, U.K
| | - Katja E. Menger
- Wellcome Centre for Mitochondrial Research, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, U.K
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, U.K
| | - James B. Stewart
- Wellcome Centre for Mitochondrial Research, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, U.K
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, U.K
| | - Thomas J. Nicholls
- Wellcome Centre for Mitochondrial Research, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, U.K
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, U.K
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Shehwar D, Barki S, Aliotta A, Veuthey L, Bertaggia Calderara D, Alberio L, Alam MR. Inhibition of mitochondrial calcium transporters alters adp-induced platelet responses. Mol Biol Rep 2024; 51:177. [PMID: 38252254 DOI: 10.1007/s11033-023-09116-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Accepted: 12/06/2023] [Indexed: 01/23/2024]
Abstract
INTRODUCTION ADP-stimulated elevation of cytosolic Ca2+ is an important effector mechanism for platelet activation. The rapidly elevating cytosolic Ca2+ is also transported to mitochondrial matrix via Mitochondrial Ca2+ Uniporter (MCU) and extruded via Na+/Ca2+/Li+ Exchanger (NCLX). However, the exact contribution of MCU and NCLX in ADP-mediated platelet responses remains incompletely understood. METHODS AND RESULTS The present study aimed to elucidate the role of mitochondrial Ca2+ transport in ADP-stimulated platelet responses by inhibition of MCU and NCLX with mitoxantrone (MTX) and CGP37157 (CGP), respectively. As these inhibitory strategies are reported to cause distinct effects on matrix Ca2+ concentration, we hypothesized to observe opposite impact of MTX and CGP on ADP-induced platelet responses. Platelet aggregation profiling was performed by microplate-based spectrophotometery while p-selectin externalization and integrin αIIbβ3 activation were analyzed by fluorescent immunolabeling using flow cytometery. Our results confirmed the expression of both MCU and NCLX mRNAs with relatively low abundance of NCLX in human platelets. In line with our hypothesis, MTX caused a dose-dependent inhibition of ADP-induced platelet aggregation without displaying any cytotoxicity. Likewise, ADP-induced p-selectin externalization and integrin αIIbβ3 activation was also significantly attenuated in MTX-treated platelets. Concordantly, inhibition of NCLX with CGP yielded an accelerated ADP-stimulated platelet aggregation which was associated with an elevation of p-selectin surface expression and αIIbβ3 activation. CONCLUSION Together, these findings uncover a vital and hitherto poorly characterized role of mitochondrial Ca2+ transporters in ADP-induced platelet activation.
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Affiliation(s)
- Durre Shehwar
- Department of Biochemistry, Quaid-I-Azam University, Islamabad, 45320, Pakistan
| | - Saima Barki
- Department of Biochemistry, Quaid-I-Azam University, Islamabad, 45320, Pakistan
| | - Alessandro Aliotta
- Hemostasis and Platelet Research Laboratory, Division of Hematology and Central Hematology Laboratory, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), CH-1010, Lausanne, Switzerland
| | - Lucas Veuthey
- Hemostasis and Platelet Research Laboratory, Division of Hematology and Central Hematology Laboratory, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), CH-1010, Lausanne, Switzerland
| | - Debora Bertaggia Calderara
- Hemostasis and Platelet Research Laboratory, Division of Hematology and Central Hematology Laboratory, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), CH-1010, Lausanne, Switzerland
| | - Lorenzo Alberio
- Hemostasis and Platelet Research Laboratory, Division of Hematology and Central Hematology Laboratory, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), CH-1010, Lausanne, Switzerland
| | - Muhammad Rizwan Alam
- Department of Biochemistry, Quaid-I-Azam University, Islamabad, 45320, Pakistan.
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Wang H, Sun X, Yang C, Li Z, Jin D, Zhu W, Yu Z. Deficiency of TOP1MT enhances glycolysis through the stimulation of PDK4 expression in gastric cancer. Cancer Metab 2024; 12:2. [PMID: 38200513 PMCID: PMC10777619 DOI: 10.1186/s40170-024-00330-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2023] [Accepted: 01/03/2024] [Indexed: 01/12/2024] Open
Abstract
BACKGROUND Abnormal glucose metabolism is one of the determinants of maintaining malignant characteristics of cancer. Targeting cancer metabolism is regarded as a new strategy for cancer treatment. Our previous studies have found that TOP1MT is a crucial gene that inhibits glycolysis and cell metastasis of gastric cancer (GC) cells, but the mechanism of its regulation of glycolysis remains unclear. METHODS Transcriptome sequencing data, clinic-pathologic features of GC from a variety of public databases, and WGCNA were used to identify novel targets of TOP1MT. Immunohistochemical results of 250 patients with GC were used to analyze the relative expression relationship between TOP1MT and PDK4. The function of TOP1MT was investigated by migration assays and sea-horse analysis in vitro. RESULTS We discovered a mitochondrial topoisomerase I, TOP1MT, which correlated with a higher risk of metastasis. Functional experiments revealed that TOP1MT deficiency promotes cell migration and glycolysis through increasing PDK4 expression. Additionally, the stimulating effect of TOP1MT on glycolysis may be effectively reversed by PDK4 inhibitor M77976. CONCLUSIONS In brief, our work demonstrated the critical function of TOP1MT in the regulation of glycolysis by PDK4 in gastric cancer. Inhibiting glycolysis and limiting tumor metastasis in GC may be accomplished by suppressing PDK4.
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Affiliation(s)
- Hongqiang Wang
- Cancer Chemotherapy Center, Zhoushan Hospital, Wenzhou Medical University, Zhoushan, China
| | - Xutao Sun
- Department of General Surgery, Zhoushan Hospital, Wenzhou Medical University, No. 739 Dingshen Road, Lincheng New District, Zhoushan, Zhejiang, 316021, China
| | - Chen Yang
- Department of General Surgery, Zhoushan Hospital, Wenzhou Medical University, No. 739 Dingshen Road, Lincheng New District, Zhoushan, Zhejiang, 316021, China
| | - Ziqi Li
- The Laboratory of Cytobiology and Molecular Biology, Zhoushan Hospital, Wenzhou Medical University, Zhoushan, China
| | - Danwen Jin
- Department of Pathology, Zhoushan Hospital, Wenzhou Medical University, Zhoushan, China
| | - Wenwen Zhu
- Cancer Chemotherapy Center, Zhoushan Hospital, Wenzhou Medical University, Zhoushan, China
| | - Ze Yu
- Department of General Surgery, Zhoushan Hospital, Wenzhou Medical University, No. 739 Dingshen Road, Lincheng New District, Zhoushan, Zhejiang, 316021, China.
- The Laboratory of Cytobiology and Molecular Biology, Zhoushan Hospital, Wenzhou Medical University, Zhoushan, China.
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Saha LK, Pommier Y. TOP3A coupling with replication forks and repair of TOP3A cleavage complexes. Cell Cycle 2024; 23:115-130. [PMID: 38341866 PMCID: PMC11037291 DOI: 10.1080/15384101.2024.2314440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Accepted: 01/08/2024] [Indexed: 02/13/2024] Open
Abstract
Humans have two Type IA topoisomerases, topoisomerase IIIα (TOP3A) and topoisomerase IIIβ (TOP3B). In this review, we focus on the role of human TOP3A in DNA replication and highlight the recent progress made in understanding TOP3A in the context of replication. Like other topoisomerases, TOP3A acts by a reversible mechanism of cleavage and rejoining of DNA strands allowing changes in DNA topology. By cleaving and resealing single-stranded DNA, it generates TOP3A-linked single-strand breaks as TOP3A cleavage complexes (TOP3Accs) with a TOP3A molecule covalently bound to the 5´-end of the break. TOP3A is critical for both mitochondrial and for nuclear DNA replication. Here, we discuss the formation and repair of irreversible TOP3Accs, as their presence compromises genome integrity as they form TOP3A DNA-protein crosslinks (TOP3A-DPCs) associated with DNA breaks. We discuss the redundant pathways that repair TOP3A-DPCs, and how their defects are a source of DNA damage leading to neurological diseases and mitochondrial disorders.
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Affiliation(s)
- Liton Kumar Saha
- Developmental Therapeutics Branch and Laboratory of Molecular Pharmacology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Yves Pommier
- Developmental Therapeutics Branch and Laboratory of Molecular Pharmacology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
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Al Khatib I, Deng J, Lei Y, Torres-Odio S, Rojas GR, Newman LE, Chung BK, Symes A, Zhang H, Huang SYN, Pommier Y, Khan A, Shadel GS, West AP, Gibson WT, Shutt TE. Activation of the cGAS-STING innate immune response in cells with deficient mitochondrial topoisomerase TOP1MT. Hum Mol Genet 2023; 32:2422-2440. [PMID: 37129502 PMCID: PMC10360396 DOI: 10.1093/hmg/ddad062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 03/22/2023] [Accepted: 04/11/2023] [Indexed: 05/03/2023] Open
Abstract
The recognition that cytosolic mitochondrial DNA (mtDNA) activates cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) innate immune signaling has unlocked novel disease mechanisms. Here, an uncharacterized variant predicted to affect TOP1MT function, P193L, was discovered in a family with multiple early onset autoimmune diseases, including Systemic Lupus Erythematosus (SLE). Although there was no previous genetic association between TOP1MT and autoimmune disease, the role of TOP1MT as a regulator of mtDNA led us to investigate whether TOP1MT could mediate the release of mtDNA to the cytosol, where it could then activate the cGAS-STING innate immune pathway known to be activated in SLE and other autoimmune diseases. Through analysis of cells with reduced TOP1MT expression, we show that loss of TOP1MT results in release of mtDNA to the cytosol, which activates the cGAS-STING pathway. We also characterized the P193L variant for its ability to rescue several TOP1MT functions when expressed in TOP1MT knockout cells. We show that the P193L variant is not fully functional, as its re-expression at high levels was unable to rescue mitochondrial respiration deficits, and only showed partial rescue for other functions, including repletion of mtDNA replication following depletion, nucleoid size, steady state mtDNA transcripts levels and mitochondrial morphology. Additionally, expression of P193L at endogenous levels was unable to rescue mtDNA release-mediated cGAS-STING signaling. Overall, we report a link between TOP1MT and mtDNA release leading to cGAS-STING activation. Moreover, we show that the P193L variant has partial loss of function that may contribute to autoimmune disease susceptibility via cGAS-STING mediated activation of the innate immune system.
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Affiliation(s)
- Iman Al Khatib
- Department of Biochemistry & Molecular Biology, Cumming School of Medicine, Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta T2N 4N1, Canada
| | - Jingti Deng
- Department of Biochemistry & Molecular Biology, Cumming School of Medicine, Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta T2N 4N1, Canada
| | - Yuanjiu Lei
- Department of Microbial Pathogenesis and Immunology, School of Medicine, Texas A&M University, Bryan, TX, USA
| | - Sylvia Torres-Odio
- Department of Microbial Pathogenesis and Immunology, School of Medicine, Texas A&M University, Bryan, TX, USA
| | - Gladys R Rojas
- The Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Laura E Newman
- The Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Brian K Chung
- Norwegian PSC Research Center, Oslo University Hospital, Rikshospitalet, Oslo, Norway
- Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Andrew Symes
- Department of Geomatics Engineering, Schulich School of Engineering, University of Calgary, Calgary, Alberta T2N 1N4, Canada
| | - Hongliang Zhang
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, NCI, National Institutes of Health, Bethesda, MD 20892, USA
| | - Shar-yin N Huang
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, NCI, National Institutes of Health, Bethesda, MD 20892, USA
| | - Yves Pommier
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, NCI, National Institutes of Health, Bethesda, MD 20892, USA
| | - Aneal Khan
- Discovery DNA, Calgary, Alberta T2L 1Y8, Canada
- M.A.G.I.C. Clinic Ltd. (Metabolics and Genetics in Calgary)
- Department of Pediatrics, Cumming School of Medicine, University of Calgary, Alberta Children's Hospital Research Institute, Calgary, Alberta T2M OL6, Canada
| | - Gerald S Shadel
- The Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Andrew Phillip West
- Department of Microbial Pathogenesis and Immunology, School of Medicine, Texas A&M University, Bryan, TX, USA
| | - William T Gibson
- Department of Medical Genetics, Faculty of Medicine, British Columbia Children's Hospital Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4, Canada
| | - Timothy E Shutt
- Departments of Medical Genetics and Biochemistry & Molecular Biology, Cumming School of Medicine, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta T2N 4N1, Canada
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10
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Lei Y, VanPortfliet JJ, Chen YF, Bryant JD, Li Y, Fails D, Torres-Odio S, Ragan KB, Deng J, Mohan A, Wang B, Brahms ON, Yates SD, Spencer M, Tong CW, Bosenberg MW, West LC, Shadel GS, Shutt TE, Upton JW, Li P, West AP. Cooperative sensing of mitochondrial DNA by ZBP1 and cGAS promotes cardiotoxicity. Cell 2023; 186:3013-3032.e22. [PMID: 37352855 PMCID: PMC10330843 DOI: 10.1016/j.cell.2023.05.039] [Citation(s) in RCA: 64] [Impact Index Per Article: 64.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 02/03/2023] [Accepted: 05/26/2023] [Indexed: 06/25/2023]
Abstract
Mitochondrial DNA (mtDNA) is a potent agonist of the innate immune system; however, the exact immunostimulatory features of mtDNA and the kinetics of detection by cytosolic nucleic acid sensors remain poorly defined. Here, we show that mitochondrial genome instability promotes Z-form DNA accumulation. Z-DNA binding protein 1 (ZBP1) stabilizes Z-form mtDNA and nucleates a cytosolic complex containing cGAS, RIPK1, and RIPK3 to sustain STAT1 phosphorylation and type I interferon (IFN-I) signaling. Elevated Z-form mtDNA, ZBP1 expression, and IFN-I signaling are observed in cardiomyocytes after exposure to Doxorubicin, a first-line chemotherapeutic agent that induces frequent cardiotoxicity in cancer patients. Strikingly, mice lacking ZBP1 or IFN-I signaling are protected from Doxorubicin-induced cardiotoxicity. Our findings reveal ZBP1 as a cooperative partner for cGAS that sustains IFN-I responses to mitochondrial genome instability and highlight ZBP1 as a potential target in heart failure and other disorders where mtDNA stress contributes to interferon-related pathology.
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Affiliation(s)
- Yuanjiu Lei
- Department of Microbial Pathogenesis and Immunology, School of Medicine, Texas A&M University, Bryan, TX 77807, USA
| | - Jordyn J VanPortfliet
- Department of Microbial Pathogenesis and Immunology, School of Medicine, Texas A&M University, Bryan, TX 77807, USA
| | - Yi-Fan Chen
- Department of Microbial Pathogenesis and Immunology, School of Medicine, Texas A&M University, Bryan, TX 77807, USA
| | - Joshua D Bryant
- Department of Microbial Pathogenesis and Immunology, School of Medicine, Texas A&M University, Bryan, TX 77807, USA
| | - Ying Li
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, USA
| | | | - Sylvia Torres-Odio
- Department of Microbial Pathogenesis and Immunology, School of Medicine, Texas A&M University, Bryan, TX 77807, USA
| | - Katherine B Ragan
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA
| | - Jingti Deng
- Departments of Medical Genetics and Biochemistry & Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 1N4, Canada
| | - Armaan Mohan
- Departments of Medical Genetics and Biochemistry & Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 1N4, Canada
| | - Bing Wang
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, USA
| | - Olivia N Brahms
- Department of Biological Sciences, Auburn University, Auburn, AL 36849, USA
| | - Shawn D Yates
- Department of Biological Sciences, Auburn University, Auburn, AL 36849, USA
| | | | - Carl W Tong
- Department of Medical Physiology, School of Medicine, Texas A&M University, Bryan, TX 77807, USA
| | - Marcus W Bosenberg
- Departments of Pathology, Dermatology, and Immunobiology, Yale School of Medicine, New Haven, CT 06520, USA
| | - Laura Ciaccia West
- Department of Microbial Pathogenesis and Immunology, School of Medicine, Texas A&M University, Bryan, TX 77807, USA
| | - Gerald S Shadel
- Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Timothy E Shutt
- Departments of Medical Genetics and Biochemistry & Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 1N4, Canada
| | - Jason W Upton
- Department of Biological Sciences, Auburn University, Auburn, AL 36849, USA
| | - Pingwei Li
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, USA
| | - A Phillip West
- Department of Microbial Pathogenesis and Immunology, School of Medicine, Texas A&M University, Bryan, TX 77807, USA.
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11
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Saha S, Pommier Y. R-loops, type I topoisomerases and cancer. NAR Cancer 2023; 5:zcad013. [PMID: 37600974 PMCID: PMC9984992 DOI: 10.1093/narcan/zcad013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 01/18/2023] [Accepted: 02/27/2023] [Indexed: 03/06/2023] Open
Abstract
R-loops are abundant and dynamic structures ubiquitously present in human cells both in the nuclear and mitochondrial genomes. They form in cis in the wake of transcription complexes and in trans apart from transcription complexes. In this review, we focus on the relationship between R-loops and topoisomerases, and cancer genomics and therapies. We summarize the topological parameters associated with the formation and resolution of R-loops, which absorb and release high levels of genomic negative supercoiling (Sc-). We review the deleterious consequences of excessive R-loops and rationalize how human type IA (TOP3B) and type IB (TOP1) topoisomerases regulate and resolve R-loops in coordination with helicase and RNase H enzymes. We also review the drugs (topoisomerase inhibitors, splicing inhibitors, G4 stabilizing ligands) and cancer predisposing genes (BRCA1/2, transcription, and splicing genes) known to induce R-loops, and whether stabilizing R-loops and thereby inducing genomic damage can be viewed as a strategy for cancer treatment.
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Affiliation(s)
- Sourav Saha
- Developmental Therapeutics Branch & Laboratory of Molecular Pharmacology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Yves Pommier
- Developmental Therapeutics Branch & Laboratory of Molecular Pharmacology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
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12
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Moreira F, Arenas M, Videira A, Pereira F. Evolution of TOP1 and TOP1MT Topoisomerases in Chordata. J Mol Evol 2023; 91:192-203. [PMID: 36651963 PMCID: PMC10081982 DOI: 10.1007/s00239-022-10091-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2022] [Accepted: 12/30/2022] [Indexed: 01/19/2023]
Abstract
Type IB topoisomerases relax the torsional stress associated with DNA metabolism in the nucleus and mitochondria and constitute important molecular targets of anticancer drugs. Vertebrates stand out among eukaryotes by having two Type IB topoisomerases acting specifically in the nucleus (TOP1) and mitochondria (TOP1MT). Despite their major importance, the origin and evolution of these paralogues remain unknown. Here, we examine the molecular evolutionary processes acting on both TOP1 and TOP1MT in Chordata, taking advantage of the increasing number of available genome sequences. We found that both TOP1 and TOP1MT evolved under strong purifying selection, as expected considering their essential biological functions. Critical active sites, including those associated with resistance to anticancer agents, were found particularly conserved. However, TOP1MT presented a higher rate of molecular evolution than TOP1, possibly related with its specialized activity on the mitochondrial genome and a less critical role in cells. We could place the duplication event that originated the TOP1 and TOP1MT paralogues early in the radiation of vertebrates, most likely associated with the first round of vertebrate tetraploidization (1R). Moreover, our data suggest that cyclostomes present a specialized mitochondrial Type IB topoisomerase. Interestingly, we identified two missense mutations replacing amino acids in the Linker region of TOP1MT in Neanderthals, which appears as a rare event when comparing the genome of both species. In conclusion, TOP1 and TOP1MT differ in their rates of evolution, and their evolutionary histories allowed us to better understand the evolution of chordates.
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Affiliation(s)
- Filipa Moreira
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos S/N 4450-208, Matosinhos, Portugal
- ICBAS - Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Rua Jorge de Viterbo Ferreira 228, 4050-313, Porto, Portugal
| | - Miguel Arenas
- Department of Biochemistry, Genetics and Immunology, University of Vigo, 36310, Vigo, Spain
- CINBIO, Universidade de Vigo, 36310, Vigo, Spain
- Galicia Sur Health Research Institute (IIS Galicia Sur), 36310, Vigo, Spain
| | - Arnaldo Videira
- ICBAS - Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Rua Jorge de Viterbo Ferreira 228, 4050-313, Porto, Portugal
- IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
- i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
| | - Filipe Pereira
- IDENTIFICA Genetic Testing, Rua Simão Bolívar 259 3º Dir Tras, 4470-214, Maia, Portugal.
- Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Calçada Martim de Freitas, 3000-456, Coimbra, Portugal.
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13
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Muralidhara P, Kumar A, Chaurasia MK, Bansal K. Topoisomerases in Immune Cell Development and Function. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2023; 210:126-133. [PMID: 36596219 PMCID: PMC7614072 DOI: 10.4049/jimmunol.2200650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 09/30/2022] [Indexed: 01/04/2023]
Abstract
DNA topoisomerases (TOPs) are complex enzymatic machines with extraordinary capacity to maintain DNA topology during torsion-intensive steps of replication and transcription. Recently, TOPs have gained significant attention for their tissue-specific function, and the vital role of TOPs in immune homeostasis and dysfunction is beginning to emerge. TOPs have been implicated in various immunological disorders such as autoimmunity, B cell immunodeficiencies, and sepsis, underscoring their importance in immune regulation. However, much remains unknown about immunological underpinnings of TOPs, and a deeper understanding of the role of TOPs in the immune system will be critical for yielding significant insights into the etiology of immunological disorders. In this review, we first discuss the recent literature highlighting the contribution of TOPs in the development of immune cells, and we further provide an overview of their importance in immune cell responses.
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Affiliation(s)
- Prerana Muralidhara
- Molecular Biology and Genetics Unit (MBGU), Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur, Bangalore 560064, India
| | - Amit Kumar
- Molecular Biology and Genetics Unit (MBGU), Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur, Bangalore 560064, India
| | - Mukesh Kumar Chaurasia
- Molecular Biology and Genetics Unit (MBGU), Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur, Bangalore 560064, India
| | - Kushagra Bansal
- Molecular Biology and Genetics Unit (MBGU), Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur, Bangalore 560064, India,Corresponding author ()
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14
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Uusküla-Reimand L, Wilson MD. Untangling the roles of TOP2A and TOP2B in transcription and cancer. SCIENCE ADVANCES 2022; 8:eadd4920. [PMID: 36322662 PMCID: PMC9629710 DOI: 10.1126/sciadv.add4920] [Citation(s) in RCA: 52] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 09/12/2022] [Indexed: 06/09/2023]
Abstract
Type II topoisomerases (TOP2) are conserved regulators of chromatin topology that catalyze reversible DNA double-strand breaks (DSBs) and are essential for maintaining genomic integrity in diverse dynamic processes such as transcription, replication, and cell division. While controlled TOP2-mediated DSBs are an elegant solution to topological constraints of DNA, DSBs also contribute to the emergence of chromosomal translocations and mutations that drive cancer. The central importance of TOP2 enzymes as frontline chemotherapeutic targets is well known; however, their precise biological functions and impact in cancer development are still poorly understood. In this review, we provide an updated overview of TOP2A and TOP2B in the regulation of chromatin topology and transcription, and discuss the recent discoveries linking TOP2 activities with cancer pathogenesis.
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Affiliation(s)
- Liis Uusküla-Reimand
- Genetics and Genome Biology Program, The Hospital for Sick Children, Toronto, ON, Canada
| | - Michael D. Wilson
- Genetics and Genome Biology Program, The Hospital for Sick Children, Toronto, ON, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
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15
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Menger KE, Chapman J, Díaz-Maldonado H, Khazeem M, Deen D, Erdinc D, Casement JW, Di Leo V, Pyle A, Rodríguez-Luis A, Cowell I, Falkenberg M, Austin C, Nicholls T. Two type I topoisomerases maintain DNA topology in human mitochondria. Nucleic Acids Res 2022; 50:11154-11174. [PMID: 36215039 PMCID: PMC9638942 DOI: 10.1093/nar/gkac857] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 09/03/2022] [Accepted: 09/26/2022] [Indexed: 11/12/2022] Open
Abstract
Genetic processes require the activity of multiple topoisomerases, essential enzymes that remove topological tension and intermolecular linkages in DNA. We have investigated the subcellular localisation and activity of the six human topoisomerases with a view to understanding the topological maintenance of human mitochondrial DNA. Our results indicate that mitochondria contain two topoisomerases, TOP1MT and TOP3A. Using molecular, genomic and biochemical methods we find that both proteins contribute to mtDNA replication, in addition to the decatenation role of TOP3A, and that TOP1MT is stimulated by mtSSB. Loss of TOP3A or TOP1MT also dysregulates mitochondrial gene expression, and both proteins promote transcription elongation in vitro. We find no evidence for TOP2 localisation to mitochondria, and TOP2B knockout does not affect mtDNA maintenance or expression. Our results suggest a division of labour between TOP3A and TOP1MT in mtDNA topology control that is required for the proper maintenance and expression of human mtDNA.
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Affiliation(s)
- Katja E Menger
- Wellcome Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
- Biosciences Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - James Chapman
- Wellcome Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
- Biosciences Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Héctor Díaz-Maldonado
- Department of Medical Biochemistry and Cell Biology, University of Gothenburg, PO Box 440, 405 30 Gothenburg, Sweden
| | - Mushtaq M Khazeem
- Biosciences Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Dasha Deen
- Wellcome Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
- Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Direnis Erdinc
- Department of Medical Biochemistry and Cell Biology, University of Gothenburg, PO Box 440, 405 30 Gothenburg, Sweden
| | - John W Casement
- Bioinformatics Support Unit, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Valeria Di Leo
- Wellcome Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
- Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Angela Pyle
- Wellcome Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
- Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Alejandro Rodríguez-Luis
- Wellcome Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
- Biosciences Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Ian G Cowell
- Biosciences Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Maria Falkenberg
- Department of Medical Biochemistry and Cell Biology, University of Gothenburg, PO Box 440, 405 30 Gothenburg, Sweden
| | - Caroline A Austin
- Biosciences Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Thomas J Nicholls
- Wellcome Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
- Biosciences Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
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16
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Al Khatib I, Deng J, Symes A, Kerr M, Zhang H, Huang SYN, Pommier Y, Khan A, Shutt TE. Functional characterization of two variants of mitochondrial topoisomerase TOP1MT that impact regulation of the mitochondrial genome. J Biol Chem 2022; 298:102420. [PMID: 36030054 PMCID: PMC9513266 DOI: 10.1016/j.jbc.2022.102420] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 08/02/2022] [Accepted: 08/03/2022] [Indexed: 11/21/2022] Open
Abstract
TOP1MT encodes a mitochondrial topoisomerase that is important for mtDNA regulation and is involved in mitochondrial replication, transcription, and translation. Two variants predicted to affect TOP1MT function (V1 - R198C and V2 - V338L) were identified by exome sequencing of a newborn with hypertrophic cardiomyopathy. As no pathogenic TOP1MT variants had been confirmed previously, we characterized these variants for their ability to rescue several TOP1MT functions in KO cells. Consistent with these TOP1MT variants contributing to the patient phenotype, our comprehensive characterization suggests that both variants had impaired activity. Critically, we determined neither variant was able to restore steady state levels of mitochondrial-encoded proteins nor to rescue oxidative phosphorylation when re-expressed in TOP1MT KO cells. However, we found the two variants behaved differently in some respects; while the V1 variant was more efficient in restoring transcript levels, the V2 variant showed better rescue of mtDNA copy number and replication. These findings suggest that the different TOP1MT variants affect distinct TOP1MT functions. Altogether, these findings begin to provide insight into the many roles that TOP1MT plays in the maintenance and expression of the mitochondrial genome and how impairments in this important protein may lead to human pathology.
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Affiliation(s)
- Iman Al Khatib
- Department of Biochemistry & Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Jingti Deng
- Department of Biochemistry & Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Andrew Symes
- Department of Geomatics Engineering, Schulich School of Engineering, University of Calgary, Calgary, Alberta, Canada
| | | | - Hongliang Zhang
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, NCI, National Institutes of Health, Bethesda, Maryland, USA
| | - Shar-Yin Naomi Huang
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, NCI, National Institutes of Health, Bethesda, Maryland, USA
| | - Yves Pommier
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, NCI, National Institutes of Health, Bethesda, Maryland, USA
| | - Aneal Khan
- Discovery DNA, Calgary, Alberta, Canada; M.A.G.I.C. Clinic Ltd (Metabolics and Genetics in Calgary), Department of Pediatrics, Cumming School of Medicine, Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
| | - Timothy E Shutt
- Departments of Biochemistry & Molecular Biology and Medical Genetics, Cumming School of Medicine, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.
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17
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Fei L, Lu Z, Xu Y, Hou G. A comprehensive pan-cancer analysis of the expression characteristics, prognostic value, and immune characteristics of TOP1MT. Front Genet 2022; 13:920897. [PMID: 36035140 PMCID: PMC9399363 DOI: 10.3389/fgene.2022.920897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Accepted: 07/12/2022] [Indexed: 12/01/2022] Open
Abstract
Background: Mitochondria are at the heart of a number of metabolic pathways providing enormous energy for normal cell growth and regulating tumor cell growth as well as survival. Mitochondrial topoisomerase I (TOP1MT) is a type IB topoisomerase found in the mitochondria of vertebrates. However, no pan-cancer analysis of TOP1MT has been reported. This study aims to explore TOP1MT expression in pan-cancer tissues and identify whether it can be a target for mitochondrial anticancer therapy. Methods and results: The original TOP1MT expression data in 33 different types of cancer patients were downloaded from the TCGA and GTEx databases. TOP1MT was highly expressed in cancer tissues, including BLCA, BRCA, CHOL, COAD, DLBC, ESCA, GBM, HNSC, KIRC, KIRP, LGG, LIHC, LUAD, LUSC, PAAD, PCPG, PRAD, READ, SKCM, STAD, THYM, UCEC, and UCS. According to Kaplan-Meier survival curve analysis, high TOP1MT expression in BLCA, HNSC, KIRP, PAAD, UCEC, and LIHC cancer tissues was linked to poor prognosis of cancer patients, i.e., poor OS, disease-specific survival, and PFI. Linkedomics analysis identified a positive correlation of TOP1MT expression with CNA, but a negative correlation with methylation. TOP1MT expression significantly correlated with immune cells and immune checkpoints in the TIMER database. Functional analysis showed a close relationship between TOP1MT expression and ribosomes. Conclusion: In summary, TOP1MT is a potential biomarker for mitochondrial anticancer therapy and cancer immunotherapy.
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Affiliation(s)
- Lihong Fei
- Department of Gastroenterology, The First Hospital of Jiaxing, Affiliated Hospital of Jiaxing University, Jiaxing, Zhejiang, China
| | - Zhimin Lu
- Department of Outpatient, The First Hospital of Jiaxing, Affiliated Hospital of Jiaxing University, Jiaxing, Zhejiang, China
| | - Yufen Xu
- Department of Oncology, The First Hospital of Jiaxing, Affiliated Hospital of Jiaxing University, Jiaxing, Zhejiang, China
- *Correspondence: Yufen Xu, ; Guoxin Hou,
| | - Guoxin Hou
- Department of Oncology, The First Hospital of Jiaxing, Affiliated Hospital of Jiaxing University, Jiaxing, Zhejiang, China
- *Correspondence: Yufen Xu, ; Guoxin Hou,
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18
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Hangas A, Kekäläinen NJ, Potter A, Michell C, Aho KJ, Rutanen C, Spelbrink JN, Pohjoismäki JL, Goffart S. Top3α is the replicative topoisomerase in mitochondrial DNA replication. Nucleic Acids Res 2022; 50:8733-8748. [PMID: 35904803 PMCID: PMC9410902 DOI: 10.1093/nar/gkac660] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 07/07/2022] [Accepted: 07/22/2022] [Indexed: 11/18/2022] Open
Abstract
Mitochondrial DNA has been investigated for nearly fifty years, but many aspects of the maintenance of this essential small genome remain unknown. Like any genome, mammalian mitochondrial DNA requires the function of topoisomerases to counter and regulate the topological tension arising during replication, transcription, segregation, and repair. However, the functions of the different mitochondrial topoisomerases are poorly understood. Here, we investigate the role of Topoisomerase 3α (Top3α) in mtDNA replication and transcription, providing evidence that this enzyme, previously reported to act in mtDNA segregation, also participates in mtDNA replication fork progression. Top3α knockdown caused replication fork stalling, increased mtDNA catenation and decreased mtDNA levels. Overexpression in contrast induced abundant double-strand breaks around the replication origin OH and abortion of early replication, while at the same time improving the resolution of mtDNA replication termination intermediates. Both Top3α knockdown and overexpression affected mitochondrial RNA transcription, leading to a decrease in steady-state levels of mitochondrial transcripts. Together, our results indicate that the mitochondrial isoform of Top3α is not only involved in mtDNA segregation, as reported previously, but also supports the progression of the replication fork. Mitochondrial Top3α is also influencing the progression of transcription, with its absence affecting downstream transcript levels.
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Affiliation(s)
- Anu Hangas
- Department of Environmental and Biological Sciences, University of Eastern Finland, PO Box 111, 80101 Joensuu, Finland
| | - Nina J Kekäläinen
- Department of Environmental and Biological Sciences, University of Eastern Finland, PO Box 111, 80101 Joensuu, Finland
| | - Alisa Potter
- Department of Environmental and Biological Sciences, University of Eastern Finland, PO Box 111, 80101 Joensuu, Finland.,Radboud Center for Mitochondrial Medicine, Department of Paediatrics, Radboudumc, Nijmegen, The Netherlands
| | - Craig Michell
- Department of Environmental and Biological Sciences, University of Eastern Finland, PO Box 111, 80101 Joensuu, Finland
| | - Kauko J Aho
- Department of Environmental and Biological Sciences, University of Eastern Finland, PO Box 111, 80101 Joensuu, Finland
| | - Chiara Rutanen
- Department of Environmental and Biological Sciences, University of Eastern Finland, PO Box 111, 80101 Joensuu, Finland
| | - Johannes N Spelbrink
- Radboud Center for Mitochondrial Medicine, Department of Paediatrics, Radboudumc, Nijmegen, The Netherlands
| | - Jaakko L Pohjoismäki
- Department of Environmental and Biological Sciences, University of Eastern Finland, PO Box 111, 80101 Joensuu, Finland
| | - Steffi Goffart
- Department of Environmental and Biological Sciences, University of Eastern Finland, PO Box 111, 80101 Joensuu, Finland
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19
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Roy A, Kandettu A, Ray S, Chakrabarty S. Mitochondrial DNA replication and repair defects: Clinical phenotypes and therapeutic interventions. BIOCHIMICA ET BIOPHYSICA ACTA. BIOENERGETICS 2022; 1863:148554. [PMID: 35341749 DOI: 10.1016/j.bbabio.2022.148554] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 03/06/2022] [Accepted: 03/16/2022] [Indexed: 12/15/2022]
Abstract
Mitochondria is a unique cellular organelle involved in multiple cellular processes and is critical for maintaining cellular homeostasis. This semi-autonomous organelle contains its circular genome - mtDNA (mitochondrial DNA), that undergoes continuous cycles of replication and repair to maintain the mitochondrial genome integrity. The majority of the mitochondrial genes, including mitochondrial replisome and repair genes, are nuclear-encoded. Although the repair machinery of mitochondria is quite efficient, the mitochondrial genome is highly susceptible to oxidative damage and other types of exogenous and endogenous agent-induced DNA damage, due to the absence of protective histones and their proximity to the main ROS production sites. Mutations in replication and repair genes of mitochondria can result in mtDNA depletion and deletions subsequently leading to mitochondrial genome instability. The combined action of mutations and deletions can result in compromised mitochondrial genome maintenance and lead to various mitochondrial disorders. Here, we review the mechanism of mitochondrial DNA replication and repair process, key proteins involved, and their altered function in mitochondrial disorders. The focus of this review will be on the key genes of mitochondrial DNA replication and repair machinery and the clinical phenotypes associated with mutations in these genes.
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Affiliation(s)
- Abhipsa Roy
- Department of Cell and Molecular Biology, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India
| | - Amoolya Kandettu
- Department of Cell and Molecular Biology, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India
| | - Swagat Ray
- Department of Life Sciences, School of Life and Environmental Sciences, University of Lincoln, Lincoln LN6 7TS, United Kingdom
| | - Sanjiban Chakrabarty
- Department of Cell and Molecular Biology, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India.
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20
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Carvalho G, Repolês BM, Mendes I, Wanrooij PH. Mitochondrial DNA Instability in Mammalian Cells. Antioxid Redox Signal 2022; 36:885-905. [PMID: 34015960 PMCID: PMC9127837 DOI: 10.1089/ars.2021.0091] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 05/11/2021] [Indexed: 02/06/2023]
Abstract
Significance: The small, multicopy mitochondrial genome (mitochondrial DNA [mtDNA]) is essential for efficient energy production, as alterations in its coding information or a decrease in its copy number disrupt mitochondrial ATP synthesis. However, the mitochondrial replication machinery encounters numerous challenges that may limit its ability to duplicate this important genome and that jeopardize mtDNA stability, including various lesions in the DNA template, topological stress, and an insufficient nucleotide supply. Recent Advances: An ever-growing array of DNA repair or maintenance factors are being reported to localize to the mitochondria. We review current knowledge regarding the mitochondrial factors that may contribute to the tolerance or repair of various types of changes in the mitochondrial genome, such as base damage, incorporated ribonucleotides, and strand breaks. We also discuss the newly discovered link between mtDNA instability and activation of the innate immune response. Critical Issues: By which mechanisms do mitochondria respond to challenges that threaten mtDNA maintenance? What types of mtDNA damage are repaired, and when are the affected molecules degraded instead? And, finally, which forms of mtDNA instability trigger an immune response, and how? Future Directions: Further work is required to understand the contribution of the DNA repair and damage-tolerance factors present in the mitochondrial compartment, as well as the balance between mtDNA repair and degradation. Finally, efforts to understand the events underlying mtDNA release into the cytosol are warranted. Pursuing these and many related avenues can improve our understanding of what goes wrong in mitochondrial disease. Antioxid. Redox Signal. 36, 885-905.
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Affiliation(s)
- Gustavo Carvalho
- Department of Medical Biochemistry and Biophysics, Umeå University, Umeå, Sweden
| | - Bruno Marçal Repolês
- Department of Medical Biochemistry and Biophysics, Umeå University, Umeå, Sweden
| | - Isabela Mendes
- Department of Medical Biochemistry and Biophysics, Umeå University, Umeå, Sweden
| | - Paulina H. Wanrooij
- Department of Medical Biochemistry and Biophysics, Umeå University, Umeå, Sweden
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21
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Pommier Y, Nussenzweig A, Takeda S, Austin C. Human topoisomerases and their roles in genome stability and organization. Nat Rev Mol Cell Biol 2022; 23:407-427. [PMID: 35228717 PMCID: PMC8883456 DOI: 10.1038/s41580-022-00452-3] [Citation(s) in RCA: 148] [Impact Index Per Article: 74.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/06/2022] [Indexed: 12/15/2022]
Abstract
Human topoisomerases comprise a family of six enzymes: two type IB (TOP1 and mitochondrial TOP1 (TOP1MT), two type IIA (TOP2A and TOP2B) and two type IA (TOP3A and TOP3B) topoisomerases. In this Review, we discuss their biochemistry and their roles in transcription, DNA replication and chromatin remodelling, and highlight the recent progress made in understanding TOP3A and TOP3B. Because of recent advances in elucidating the high-order organization of the genome through chromatin loops and topologically associating domains (TADs), we integrate the functions of topoisomerases with genome organization. We also discuss the physiological and pathological formation of irreversible topoisomerase cleavage complexes (TOPccs) as they generate topoisomerase DNA–protein crosslinks (TOP-DPCs) coupled with DNA breaks. We discuss the expanding number of redundant pathways that repair TOP-DPCs, and the defects in those pathways, which are increasingly recognized as source of genomic damage leading to neurological diseases and cancer. Topoisomerases have essential roles in transcription, DNA replication, chromatin remodelling and, as recently revealed, 3D genome organization. However, topoisomerases also generate DNA–protein crosslinks coupled with DNA breaks, which are increasingly recognized as a source of disease-causing genomic damage.
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Bhattacharjee S, Rehman I, Nandy S, Das BB. Post-translational regulation of Tyrosyl-DNA phosphodiesterase (TDP1 and TDP2) for the repair of the trapped topoisomerase-DNA covalent complex. DNA Repair (Amst) 2022; 111:103277. [DOI: 10.1016/j.dnarep.2022.103277] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 12/24/2021] [Accepted: 01/20/2022] [Indexed: 12/23/2022]
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Trapped topoisomerase-DNA covalent complexes in the mitochondria and their role in human diseases. Mitochondrion 2021; 60:234-244. [PMID: 34500116 DOI: 10.1016/j.mito.2021.08.017] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/24/2021] [Accepted: 08/27/2021] [Indexed: 11/22/2022]
Abstract
Topoisomerases regulate DNA topology, organization of the intracellular DNA, the transmission of genetic materials, and gene expressions. Other than the nuclear genome, mitochondria also harbor the small, circular DNA (mtDNA) that encodes a critical subset of proteins for the production of cellular ATP; however, mitochondria are solely dependent on the nucleus for all the mitochondrial proteins necessary for mtDNA replication, repair, and maintenance. Mitochondrial genome compiles topological stress from bidirectional transcription and replication, therefore imports four nuclear encoded topoisomerases (Top1mt, Top2α, Top2β, and Top3α) in the mitochondria to relax mtDNA supercoiling generated during these processes. Trapping of topoisomerase on DNA results in the formation of protein-linked DNA adducts (PDAs), which are widely exploited by topoisomerase-targeting anticancer drugs. Intriguingly mtDNA is potentially exposed to DNA damage that has been attributed to a variety of human diseases, including neurodegeneration, cancer, and premature aging. In this review, we focus on the role of different topoisomerases in the mitochondria and our current understanding of the mitochondrial DNA damage through trapped protein-DNA complexes, and the progress in the molecular mechanisms of the repair for trapped topoisomerase covalent complexes (Topcc). Finally, we have discussed how the pathological DNA lesions that cause mtDNA damage,trigger mitochondrial fission and mitophagy, which serve as quality control events for clearing damaged mtDNA.
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Menger KE, Rodríguez-Luis A, Chapman J, Nicholls TJ. Controlling the topology of mammalian mitochondrial DNA. Open Biol 2021; 11:210168. [PMID: 34547213 PMCID: PMC8455175 DOI: 10.1098/rsob.210168] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The genome of mitochondria, called mtDNA, is a small circular DNA molecule present at thousands of copies per human cell. MtDNA is packaged into nucleoprotein complexes called nucleoids, and the density of mtDNA packaging affects mitochondrial gene expression. Genetic processes such as transcription, DNA replication and DNA packaging alter DNA topology, and these topological problems are solved by a family of enzymes called topoisomerases. Within mitochondria, topoisomerases are involved firstly in the regulation of mtDNA supercoiling and secondly in disentangling interlinked mtDNA molecules following mtDNA replication. The loss of mitochondrial topoisomerase activity leads to defects in mitochondrial function, and variants in the dual-localized type IA topoisomerase TOP3A have also been reported to cause human mitochondrial disease. We review the current knowledge on processes that alter mtDNA topology, how mtDNA topology is modulated by the action of topoisomerases, and the consequences of altered mtDNA topology for mitochondrial function and human health.
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Affiliation(s)
- Katja E. Menger
- Wellcome Centre for Mitochondrial Research, Biosciences Institute, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - Alejandro Rodríguez-Luis
- Wellcome Centre for Mitochondrial Research, Biosciences Institute, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - James Chapman
- Wellcome Centre for Mitochondrial Research, Biosciences Institute, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - Thomas J. Nicholls
- Wellcome Centre for Mitochondrial Research, Biosciences Institute, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
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Sutormin DA, Galivondzhyan AK, Polkhovskiy AV, Kamalyan SO, Severinov KV, Dubiley SA. Diversity and Functions of Type II Topoisomerases. Acta Naturae 2021; 13:59-75. [PMID: 33959387 PMCID: PMC8084294 DOI: 10.32607/actanaturae.11058] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 10/09/2020] [Indexed: 11/29/2022] Open
Abstract
The DNA double helix provides a simple and elegant way to store and copy genetic information. However, the processes requiring the DNA helix strands separation, such as transcription and replication, induce a topological side-effect - supercoiling of the molecule. Topoisomerases comprise a specific group of enzymes that disentangle the topological challenges associated with DNA supercoiling. They relax DNA supercoils and resolve catenanes and knots. Here, we review the catalytic cycles, evolution, diversity, and functional roles of type II topoisomerases in organisms from all domains of life, as well as viruses and other mobile genetic elements.
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Affiliation(s)
- D. A. Sutormin
- Institute of Gene Biology RAS, Moscow, 119334 Russia
- Centre for Life Sciences, Skolkovo Institute of Science and Technology, Moscow, 121205 Russia
| | - A. K. Galivondzhyan
- Lomonosov Moscow State University, Moscow, 119991 Russia
- Institute of Molecular Genetics RAS, Moscow, 123182 Russia
| | - A. V. Polkhovskiy
- Institute of Gene Biology RAS, Moscow, 119334 Russia
- Centre for Life Sciences, Skolkovo Institute of Science and Technology, Moscow, 121205 Russia
| | - S. O. Kamalyan
- Institute of Gene Biology RAS, Moscow, 119334 Russia
- Centre for Life Sciences, Skolkovo Institute of Science and Technology, Moscow, 121205 Russia
| | - K. V. Severinov
- Centre for Life Sciences, Skolkovo Institute of Science and Technology, Moscow, 121205 Russia
- Centre for Precision Genome Editing and Genetic Technologies for Biomedicine, Institute of Gene Biology RAS, Moscow, 119334 Russia
- Waksman Institute for Microbiology, Piscataway, New Jersey, 08854 USA
| | - S. A. Dubiley
- Institute of Gene Biology RAS, Moscow, 119334 Russia
- Centre for Life Sciences, Skolkovo Institute of Science and Technology, Moscow, 121205 Russia
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Zagnoli-Vieira G, Caldecott KW. Untangling trapped topoisomerases with tyrosyl-DNA phosphodiesterases. DNA Repair (Amst) 2020; 94:102900. [PMID: 32653827 DOI: 10.1016/j.dnarep.2020.102900] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 06/14/2020] [Accepted: 06/14/2020] [Indexed: 02/08/2023]
Abstract
DNA topoisomerases alleviate the torsional stress that is generated by processes that are central to genome metabolism such as transcription and DNA replication. To do so, these enzymes generate an enzyme intermediate known as the cleavage complex in which the topoisomerase is covalently linked to the termini of a DNA single- or double-strand break. Whilst cleavage complexes are normally transient they can occasionally become abortive, creating protein-linked DNA breaks that threaten genome stability and cell survival; a process promoted and exploited in the cancer clinic by the use of topoisomerase 'poisons'. Here, we review the consequences to genome stability and human health of abortive topoisomerase-induced DNA breakage and the cellular pathways that cells have adopted to mitigate them, with particular focus on an important class of enzymes known as tyrosyl-DNA phosphodiesterases.
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Affiliation(s)
- Guido Zagnoli-Vieira
- Wellcome Trust Cancer Research UK Gurdon Institute, Tennis Court Road, Cambridge, CB2 1QN, UK.
| | - Keith W Caldecott
- Genome Damage Stability Centre, University of Sussex, Falmer Road, Brighton, BN1 9RQ, UK.
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Falkenberg M, Gustafsson CM. Mammalian mitochondrial DNA replication and mechanisms of deletion formation. Crit Rev Biochem Mol Biol 2020; 55:509-524. [DOI: 10.1080/10409238.2020.1818684] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- Maria Falkenberg
- Department of Medical Biochemistry and Cell Biology, University of Gothenburg, Gothenburg, Sweden
| | - Claes M. Gustafsson
- Department of Medical Biochemistry and Cell Biology, University of Gothenburg, Gothenburg, Sweden
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Hou G, Deng J, You X, Chen J, Jiang Y, Qian T, Bi Y, Song B, Xu Y, Yang X. Mining topoisomerase isoforms in gastric cancer. Gene 2020; 754:144859. [PMID: 32535049 DOI: 10.1016/j.gene.2020.144859] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 05/20/2020] [Accepted: 06/05/2020] [Indexed: 01/04/2023]
Abstract
DNA topoisomerases essentially remove topological strains generated during DNA replication, transcription, DNA repair, and other cytogenetic processes. However, distinct expression level and prognostic significance of individual topoisomerase isoforms in gastric cancer (GC) remain largely unexplored. In this study, we utilized Oncomine and Kaplan-Meier plotter database to detect the mRNA expression level of individual topoisomerase isoforms as well as assess their prognostic significance in GC patients. With the exception of TOP3B and TOP2B, levels of all topoisomerase isoforms were found to be elevated in GC patients when compared to the normal tissues. Elevated expression of TOP1 and TOP1MT was relevant to longer overall survival (OS) in GC and gastric intestinal type adenocarcinoma (GITA) patients, but not in diffuse gastric adenocarcinoma (DFA) patients. Increased expression of TOP2A and TOP2B was related to better OS in GC, as well as in GITA and DFA patients. In contrast, increased expression TOP3A and TOP3B was associated with shorter OS in GC, as well as in GITA and DFA patients. We also applied the Tumor IMmune Estimation Resource (TIMER) tool to assess the correlations between distinct topoisomerase isoforms and the infiltrating immune cell landscape. Furthermore, we found that down-regulating the expression of TOP3A by shRNA significantly inhibited the proliferation and colony formation in GC cells compared to control shRNA treated cells. Thus our study lays the framework for utilizing topoisomerases in better understanding the complexity and heterogeneity of GC and for developing strategies for novel customized therapy in GC patients.
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Affiliation(s)
- Guoxin Hou
- Department of Oncology, The First Hospital of Jiaxing, Affiliated Hospital of Jiaxing University, Jiaxing, Zhejiang, China
| | - Jingjing Deng
- Department of Respiratory, The First Hospital of Jiaxing, Affiliated Hospital of Jiaxing University, Jiaxing, Zhejiang, China
| | - Xin You
- The First Department of Chemotherapy, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China
| | - Jing Chen
- Department of Oncology, The First Hospital of Jiaxing, Affiliated Hospital of Jiaxing University, Jiaxing, Zhejiang, China
| | - Yiming Jiang
- Department of Oncology, The First Hospital of Jiaxing, Affiliated Hospital of Jiaxing University, Jiaxing, Zhejiang, China
| | - Tingting Qian
- Department of Oncology, The First Hospital of Jiaxing, Affiliated Hospital of Jiaxing University, Jiaxing, Zhejiang, China
| | - Yanyu Bi
- Department of Oncology, The First Hospital of Jiaxing, Affiliated Hospital of Jiaxing University, Jiaxing, Zhejiang, China
| | - Binbin Song
- Department of Oncology, The First Hospital of Jiaxing, Affiliated Hospital of Jiaxing University, Jiaxing, Zhejiang, China
| | - Yufen Xu
- Department of Oncology, The First Hospital of Jiaxing, Affiliated Hospital of Jiaxing University, Jiaxing, Zhejiang, China
| | - Xinmei Yang
- Department of Oncology, The First Hospital of Jiaxing, Affiliated Hospital of Jiaxing University, Jiaxing, Zhejiang, China.
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Sala V, Della Sala A, Hirsch E, Ghigo A. Signaling Pathways Underlying Anthracycline Cardiotoxicity. Antioxid Redox Signal 2020; 32:1098-1114. [PMID: 31989842 DOI: 10.1089/ars.2020.8019] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Significance: The cardiac side effects of hematological treatments are a major issue of the growing population of cancer survivors, often affecting patient survival even more than the tumor for which the treatment was initially prescribed. Among the most cardiotoxic drugs are anthracyclines (ANTs), highly potent antitumor agents, which still represent a mainstay in the treatment of hematological and solid tumors. Unfortunately, diagnosis, prevention, and treatment of cardiotoxicity are still unmet clinical needs, which call for a better understanding of the molecular mechanism behind the pathology. Recent Advances: This review article will discuss recent findings on the pathomechanisms underlying the cardiotoxicity of ANTs, spanning from DNA and mitochondrial damage to calcium homeostasis, autophagy, and apoptosis. Special emphasis will be given to the role of reactive oxygen species and their interplay with major signaling pathways. Critical Issues: Although new promising therapeutic targets and new drugs have started to be identified, their efficacy has been mainly proven in preclinical studies and requires clinical validation. Future Directions: Future studies are awaited to confirm the relevance of recently uncovered targets, as well as to identify new druggable pathways, in more clinically relevant models, including, for example, human induced pluripotent stem cell-derived cardiomyocytes.
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Affiliation(s)
- Valentina Sala
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy
| | - Angela Della Sala
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy
| | - Emilio Hirsch
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy
| | - Alessandra Ghigo
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy
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Fang Y, Akimoto M, Mayanagi K, Hatano A, Matsumoto M, Matsuda S, Yasukawa T, Kang D. Chemical acetylation of mitochondrial transcription factor A occurs on specific lysine residues and affects its ability to change global DNA topology. Mitochondrion 2020; 53:99-108. [PMID: 32439622 DOI: 10.1016/j.mito.2020.05.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 05/08/2020] [Accepted: 05/14/2020] [Indexed: 12/20/2022]
Abstract
Chemical acetylation is postulated to occur in mitochondria. Mitochondrial transcription factor A (TFAM or mtTFA), a mitochondrial transcription initiation factor as well as the major mitochondrial nucleoid protein coating the entire mitochondrial genome, is proposed to be acetylated in animals and cultured cells. This study investigated the properties of human TFAM, in conjunction with the mechanism and effects of TFAM acetylation in vitro. Using highly purified recombinant human TFAM and 3 kb circular DNA as a downsized mtDNA model, we studied how the global TFAM-DNA interaction is affected/regulated by the quantitative TFAM-DNA relationship and TFAM acetylation. Results showed that the TFAM-DNA ratio strictly affects the TFAM property to unwind circular DNA in the presence of topoisomerase I. Mass spectrometry analysis showed that in vitro chemical acetylation of TFAM with acetyl-coenzyme A occurs preferentially on specific lysine residues, including those reported to be acetylated in exogenously expressed TFAM in cultured human cells, indicating that chemical acetylation plays a crucial role in TFAM acetylation in mitochondria. Intriguingly, the modification significantly decreased TFAM's DNA-unwinding ability, while its DNA-binding ability was largely unaffected. Altogether, we propose TFAM is chemically acetylated in vivo, which could change mitochondrial DNA topology, leading to copy number and gene expression modulation.
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Affiliation(s)
- Yuan Fang
- Department of Clinical Chemistry and Laboratory Medicine, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka-shi, Fukuoka 812-8582, Japan
| | - Masaru Akimoto
- Department of Clinical Chemistry and Laboratory Medicine, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka-shi, Fukuoka 812-8582, Japan; Department of Clinical Chemistry and Laboratory Medicine, Kyushu University Hospital, 3-1-1 Maidashi, Higashi-ku, Fukuoka-shi, Fukuoka 812-8582, Japan
| | - Kouta Mayanagi
- Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka-shi, Fukuoka 812-8582, Japan
| | - Atsushi Hatano
- Department of Omics and Systems Biology, Graduate School of Medical and Dental Sciences, Niigata University, 757 Ichibancho, Asahimachi-dori, Chuo-ku, Niigata-shi, Niigata 951-8510, Japan
| | - Masaki Matsumoto
- Department of Omics and Systems Biology, Graduate School of Medical and Dental Sciences, Niigata University, 757 Ichibancho, Asahimachi-dori, Chuo-ku, Niigata-shi, Niigata 951-8510, Japan
| | - Shigeru Matsuda
- Department of Clinical Chemistry and Laboratory Medicine, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka-shi, Fukuoka 812-8582, Japan
| | - Takehiro Yasukawa
- Department of Clinical Chemistry and Laboratory Medicine, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka-shi, Fukuoka 812-8582, Japan.
| | - Dongchon Kang
- Department of Clinical Chemistry and Laboratory Medicine, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka-shi, Fukuoka 812-8582, Japan
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Mishmar D, Levin R, Naeem MM, Sondheimer N. Higher Order Organization of the mtDNA: Beyond Mitochondrial Transcription Factor A. Front Genet 2019; 10:1285. [PMID: 31998357 PMCID: PMC6961661 DOI: 10.3389/fgene.2019.01285] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 11/21/2019] [Indexed: 01/09/2023] Open
Abstract
The higher order organization of eukaryotic and prokaryotic genomes is pivotal in the regulation of gene expression. Specifically, chromatin accessibility in eukaryotes and nucleoid accessibility in bacteria are regulated by a cohort of proteins to alter gene expression in response to diverse physiological conditions. By contrast, prior studies have suggested that the mitochondrial genome (mtDNA) is coated solely by mitochondrial transcription factor A (TFAM), whose increased cellular concentration was proposed to be the major determinant of mtDNA packaging in the mitochondrial nucleoid. Nevertheless, recent analysis of DNase-seq and ATAC-seq experiments from multiple human and mouse samples suggest gradual increase in mtDNA occupancy during the course of embryonic development to generate a conserved footprinting pattern which correlate with sites that have low TFAM occupancy in vivo (ChIP-seq) and tend to adopt G-quadruplex structures. These findings, along with recent identification of mtDNA binding by known modulators of chromatin accessibility such as MOF, suggest that mtDNA higher order organization is generated by cross talk with the nuclear regulatory system, may have a role in mtDNA regulation, and is more complex than once thought.
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Affiliation(s)
- Dan Mishmar
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Rotem Levin
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Mansur M Naeem
- Institute of Medical Sciences and the Department of Paediatrics, The University of Toronto, Toronto, ON, Canada
| | - Neal Sondheimer
- Institute of Medical Sciences and the Department of Paediatrics, The University of Toronto, Toronto, ON, Canada
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Abstract
DNA replication in human mitochondria has been studied for several decades; however, its mechanism still remains unclear. During the last 15 years, many new experimental data on the mitochondrial replication have appeared, although extremely contradictory. Two asynchronous (strand displacement and RITOLS) and one synchronous (strand-coupled) replication models have been proposed. In the asynchronous models, replication from the origin in the H-chain starts earlier, so that the replication of the two chains ends at different times. The synchronous model is more traditional and implies two replication forks with leading and lagging strands initiated at the same origin. For each of the three models, both confirming and contradicting experimental data exist. Most likely, there is no single model of mitochondrial replication. It is possible that the unique mitochondrial replication machinery that has originated as a results of endosymbiosis has an unexpected variety of replication strategies to maintain the mitochondrial genome. An unusual combination of enzymes of different origin (phage, bacterial, eukaryotic) and unique features of the mitochondrial genome (existance of heavy and light chains, insertions of ribonucleotides, a variety of origins) can allow replication through different mechanisms. In human mitochondria, asynchronous replication seems to dominate; however, synchronous replication is also possible under certain conditions. In the human heart mitochondria, circular mitochondrial DNA (mtDNA) molecules can rearrange in a network of rapidly replicating linear genomes, thereby suggesting possible existence of a wide range of replication mechanisms in the mitochondria. The review describes the main stages of mtDNA replication and enzymes involved in this process, as well as discusses the prospects of mitochondrial replication studies.
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Affiliation(s)
- L A Zinovkina
- Lomonosov Moscow State University, Faculty of Bioengineering and Bioinformatics, Moscow, 119234, Russia.
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Ghosh A, Bhattacharjee S, Chowdhuri SP, Mallick A, Rehman I, Basu S, Das BB. SCAN1-TDP1 trapping on mitochondrial DNA promotes mitochondrial dysfunction and mitophagy. SCIENCE ADVANCES 2019; 5:eaax9778. [PMID: 31723605 PMCID: PMC6834389 DOI: 10.1126/sciadv.aax9778] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Accepted: 09/17/2019] [Indexed: 05/03/2023]
Abstract
A homozygous mutation of human tyrosyl-DNA phosphodiesterase 1 (TDP1) causes the neurodegenerative syndrome, spinocerebellar ataxia with axonal neuropathy (SCAN1). TDP1 hydrolyzes the phosphodiester bond between DNA 3'-end and a tyrosyl moiety within trapped topoisomerase I (Top1)-DNA covalent complexes (Top1cc). TDP1 is critical for mitochondrial DNA (mtDNA) repair; however, the role of mitochondria remains largely unknown for the etiology of SCAN1. We demonstrate that mitochondria in cells expressing SCAN1-TDP1 (TDP1H493R) are selectively trapped on mtDNA in the regulatory non-coding region and promoter sequences. Trapped TDP1H493R-mtDNA complexes were markedly increased in the presence of the Top1 poison (mito-SN38) when targeted selectively into mitochondria in nanoparticles. TDP1H493R-trapping accumulates mtDNA damage and triggers Drp1-mediated mitochondrial fission, which blocks mitobiogenesis. TDP1H493R prompts PTEN-induced kinase 1-dependent mitophagy to eliminate dysfunctional mitochondria. SCAN1-TDP1 in mitochondria creates a pathological state that allows neurons to turn on mitophagy to rescue fit mitochondria as a mechanism of survival.
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Affiliation(s)
- Arijit Ghosh
- Laboratory of Molecular Biology, School of Biological Sciences, Indian Association for the Cultivation of Science, 2A & B, Raja S. C. Mullick Road, Jadavpur, Kolkata 700032, India
| | - Sangheeta Bhattacharjee
- Laboratory of Molecular Biology, School of Biological Sciences, Indian Association for the Cultivation of Science, 2A & B, Raja S. C. Mullick Road, Jadavpur, Kolkata 700032, India
| | - Srijita Paul Chowdhuri
- Laboratory of Molecular Biology, School of Biological Sciences, Indian Association for the Cultivation of Science, 2A & B, Raja S. C. Mullick Road, Jadavpur, Kolkata 700032, India
| | - Abhik Mallick
- Department of Chemistry, Indian Institute of Science Education and Research (IISER) Pune, Dr. Homi Bhabha Road, Pashan, Pune, Maharashtra 411008, India
| | - Ishita Rehman
- Laboratory of Molecular Biology, School of Biological Sciences, Indian Association for the Cultivation of Science, 2A & B, Raja S. C. Mullick Road, Jadavpur, Kolkata 700032, India
| | - Sudipta Basu
- Discipline of Chemistry, Indian Institute of Technology (IIT) Gandhinagar, Palaj, Gandhinagar, Gujarat 382355, India
| | - Benu Brata Das
- Laboratory of Molecular Biology, School of Biological Sciences, Indian Association for the Cultivation of Science, 2A & B, Raja S. C. Mullick Road, Jadavpur, Kolkata 700032, India
- Corresponding author.
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Zilocchi M, Fasano M, Alberio T. Mitochondrial Proteins in the Development of Parkinson’s Disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1158:17-44. [DOI: 10.1007/978-981-13-8367-0_2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Baechler SA, Dalla Rosa I, Spinazzola A, Pommier Y. Beyond the unwinding: role of TOP1MT in mitochondrial translation. Cell Cycle 2019; 18:2377-2384. [PMID: 31345095 DOI: 10.1080/15384101.2019.1646563] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Mitochondria contain their own genome (mtDNA), encoding 13 proteins of the enzyme complexes of the oxidative phosphorylation. Synthesis of these 13 mitochondrial proteins requires a specific translation machinery, the mitoribosomes whose RNA components are encoded by the mtDNA, whereas more than 80 proteins are encoded by nuclear genes. It has been well established that mitochondrial topoisomerase I (TOP1MT) is important for mtDNA integrity and mitochondrial transcription as it prevents excessive mtDNA negative supercoiling and releases topological stress during mtDNA replication and transcription. We recently showed that TOP1MT also supports mitochondrial protein synthesis, and thus is critical for promoting tumor growth. Impaired mitochondrial protein synthesis leads to activation of the mitonuclear stress response through the transcription factor ATF4, and induces cytoprotective genes in order to prevent mitochondrial and cellular dysfunction. In this perspective, we highlight the novel role of TOP1MT in mitochondrial protein synthesis and as potential target for chemotherapy.
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Affiliation(s)
- Simone A Baechler
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, National Cancer Institute, NIH , Bethesda , MD , USA
| | - Ilaria Dalla Rosa
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology , London , UK
| | - Antonella Spinazzola
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology , London , UK
| | - Yves Pommier
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, National Cancer Institute, NIH , Bethesda , MD , USA
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Mammalian Tyrosyl-DNA Phosphodiesterases in the Context of Mitochondrial DNA Repair. Int J Mol Sci 2019; 20:ijms20123015. [PMID: 31226795 PMCID: PMC6628236 DOI: 10.3390/ijms20123015] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2019] [Revised: 06/14/2019] [Accepted: 06/18/2019] [Indexed: 01/03/2023] Open
Abstract
Mammalian mitochondria contain four topoisomerases encoded in the nuclear genome: TOP1MT, TOP2α, TOP2β, and TOP3α. They also contain the two known tyrosyl-DNA phosphodiesterases (TDPs): TDP1 and TDP2, including a specific TDP2S isoform. Both TDP1 and TDP2 excise abortive topoisomerase cleavage complexes (TOPccs), yet their molecular structures and mechanisms are different. TDP1 is present across eukaryotes, from yeasts to humans and belongs to the phospholipase D family. It functions without a metal cofactor and has a broad activity range, as it also serves to cleanse blocking 3′-DNA ends bearing phosphoglycolate, deoxyribose phosphate, nucleoside, nucleoside analogs (zidovudine), abasic moieties, and with a lower efficiency, TOP2ccs. Found in higher vertebrates, TDP2 is absent in yeast where TDP1 appears to perform its functions. TDP2 belongs to the exonuclease/endonuclease/phosphodiesterase family and requires magnesium as a cofactor to excise TOP2ccs, and it also excises TOP1ccs, albeit with a lower efficiency. Here, we review TDP1 and TDP2 in the context of mitochondrial DNA repair and discuss potential new research areas centered on the mitochondrial TDPs.
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Melo-Hanchuk TD, Slepicka PF, Pelegrini AL, Menck CFM, Kobarg J. NEK5 interacts with topoisomerase IIβ and is involved in the DNA damage response induced by etoposide. J Cell Biochem 2019; 120:16853-16866. [PMID: 31090963 DOI: 10.1002/jcb.28943] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 04/16/2019] [Accepted: 04/18/2019] [Indexed: 02/06/2023]
Abstract
Cells are daily submitted to high levels of DNA lesions that trigger complex pathways and cellular responses by cell cycle arrest, apoptosis, alterations in transcriptional response, and the onset of DNA repair. Members of the NIMA-related kinase (NEK) family have been related to DNA damage response and repair and the first insight about NEK5 in this context is related to its role in centrosome separation resulting in defects in chromosome integrity. Here we investigate the potential correlation between NEK5 and the DNA damage repair index. The effect of NEK5 in double-strand breaks caused by etoposide was accessed by alkaline comet assay and revealed that NEK5-silenced cells are more sensitive to etoposide treatment. Topoisomerase IIβ (TOPIIβ) is a target of etoposide that leads to the production of DNA breaks. We demonstrate that NEK5 interacts with TOPIIβ, and the dynamics of this interaction is evaluated by proximity ligation assay. The complex NEK5/TOPIIβ is formed immediately after etoposide treatment. Taken together, the results of our study reveal that NEK5 depletion increases DNA damage and impairs proper DNA damage response, pointing out NEK5 as a potential kinase contributor to genomic stability.
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Affiliation(s)
- Talita Diniz Melo-Hanchuk
- Departamento de Bioquímica e Biologia Tecidual, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil
| | - Priscila Ferreira Slepicka
- Laboratório Nacional de Biociências, Centro Nacional de Pesquisa em Energia e Materiais, Campinas, São Paulo, Brazil
| | - Alessandra Luiza Pelegrini
- Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
| | | | - Jörg Kobarg
- Departamento de Bioquímica e Biologia Tecidual, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil.,Faculdade de Ciências Farmacêuticas, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil
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Twist and Turn-Topoisomerase Functions in Mitochondrial DNA Maintenance. Int J Mol Sci 2019; 20:ijms20082041. [PMID: 31027213 PMCID: PMC6514783 DOI: 10.3390/ijms20082041] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Revised: 04/22/2019] [Accepted: 04/24/2019] [Indexed: 12/15/2022] Open
Abstract
Like any genome, mitochondrial DNA (mtDNA) also requires the action of topoisomerases to resolve topological problems in its maintenance, but for a long time, little was known about mitochondrial topoisomerases. The last years have brought a closer insight into the function of these fascinating enzymes in mtDNA topology regulation, replication, transcription, and segregation. Here, we summarize the current knowledge about mitochondrial topoisomerases, paying special attention to mammalian mitochondrial genome maintenance. We also discuss the open gaps in the existing knowledge of mtDNA topology control and the potential involvement of mitochondrial topoisomerases in human pathologies. While Top1mt, the only exclusively mitochondrial topoisomerase in mammals, has been studied intensively for nearly a decade, only recent studies have shed some light onto the mitochondrial function of Top2β and Top3α, enzymes that are shared between nucleus and mitochondria. Top3α mediates the segregation of freshly replicated mtDNA molecules, and its dysfunction leads to mtDNA aggregation and copy number depletion in patients. Top2β, in contrast, regulates mitochondrial DNA replication and transcription through the alteration of mtDNA topology, a fact that should be acknowledged due to the frequent use of Topoisomerase 2 inhibitors in medical therapy.
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Fief CA, Hoang KG, Phipps SD, Wallace JL, Deweese JE. Examining the Impact of Antimicrobial Fluoroquinolones on Human DNA Topoisomerase IIα and IIβ. ACS OMEGA 2019; 4:4049-4055. [PMID: 31459613 PMCID: PMC6648947 DOI: 10.1021/acsomega.8b03428] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 02/11/2019] [Indexed: 05/29/2023]
Abstract
Fluoroquinolones are a class of widely prescribed antibiotics with a broad range of activity against Gram-positive, Gram-negative, and some atypical microbes. Unfortunately, these drugs are associated with significant adverse events including neuropathy, tendinopathy, cardiac rhythm abnormalities, and mental health side effects. The mechanism by which fluoroquinolones cause many of these toxicities is unknown. The antibacterial mechanism of action involves disruption of the catalytic mechanism of type-II topoisomerases in bacteria, namely topoisomerase IV and DNA gyrase. Fluoroquinolones inhibit the ability of the enzymes to ligate cleaved DNA and result in single- and double-stranded DNA breaks. Thus, there is an interest in investigating whether human topoisomerase II is involved in mediating the adverse events associated with quinolones. Previous studies demonstrate some response of human topoisomerase IIα and IIβ to high levels of ciprofloxacin. However, it is not clear whether the concentration of ciprofloxacin utilized in those studies corresponds to concentrations that would be routinely achievable in patients. Therefore, this study set out to examine three clinically relevant fluoroquinolones along with two older agents to determine whether these compounds display activity against topoisomerase IIα and IIβ at drug concentrations that more closely approximate typical patient plasma values. On the basis of our evidence, none of the quinolones studied were able to poison DNA cleavage by either human enzyme. Ciprofloxacin, desethylene-ciprofloxacin, and the recently removed from market gemifloxacin were able to inhibit topoisomerase II-mediated DNA relaxation at concentrations of 200-300 μM. On the basis of these data, we propose that human topoisomerase II is not likely to be the main cause of these adverse events and that additional targets need to be identified to clarify the mechanisms underlying quinolone toxicities.
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Affiliation(s)
- Cole A. Fief
- Department
of Pharmaceutical Sciences and Department of Pharmacy Practice, Lipscomb University College of Pharmacy and Health
Sciences, One University Park Drive, Nashville, Tennessee 37204-3951, United States
| | - Kristine G. Hoang
- Department
of Pharmaceutical Sciences and Department of Pharmacy Practice, Lipscomb University College of Pharmacy and Health
Sciences, One University Park Drive, Nashville, Tennessee 37204-3951, United States
| | - Stephen D. Phipps
- Department
of Pharmaceutical Sciences and Department of Pharmacy Practice, Lipscomb University College of Pharmacy and Health
Sciences, One University Park Drive, Nashville, Tennessee 37204-3951, United States
| | - Jessica L. Wallace
- Department
of Pharmaceutical Sciences and Department of Pharmacy Practice, Lipscomb University College of Pharmacy and Health
Sciences, One University Park Drive, Nashville, Tennessee 37204-3951, United States
- Veterans
Affairs Tennessee Valley Healthcare System, 1310 24th, Avenue South, Nashville, Tennessee 37232, United States
| | - Joseph E. Deweese
- Department
of Pharmaceutical Sciences and Department of Pharmacy Practice, Lipscomb University College of Pharmacy and Health
Sciences, One University Park Drive, Nashville, Tennessee 37204-3951, United States
- Department
of Biochemistry, Vanderbilt University School
of Medicine, 2215 Garland
Avenue, Nashville, Tennessee 37232-0146, United States
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40
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Baechler SA, Factor VM, Dalla Rosa I, Ravji A, Becker D, Khiati S, Miller Jenkins LM, Lang M, Sourbier C, Michaels SA, Neckers LM, Zhang HL, Spinazzola A, Huang SN, Marquardt JU, Pommier Y. The mitochondrial type IB topoisomerase drives mitochondrial translation and carcinogenesis. Nat Commun 2019; 10:83. [PMID: 30622257 PMCID: PMC6325124 DOI: 10.1038/s41467-018-07922-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 11/28/2018] [Indexed: 01/23/2023] Open
Abstract
Mitochondrial topoisomerase IB (TOP1MT) is a nuclear-encoded topoisomerase, exclusively localized to mitochondria, which resolves topological stress generated during mtDNA replication and transcription. Here, we report that TOP1MT is overexpressed in cancer tissues and demonstrate that TOP1MT deficiency attenuates tumor growth in human and mouse models of colon and liver cancer. Due to their mitochondrial dysfunction, TOP1MT-KO cells become addicted to glycolysis, which limits synthetic building blocks and energy supply required for the proliferation of cancer cells in a nutrient-deprived tumor microenvironment. Mechanistically, we show that TOP1MT associates with mitoribosomal subunits, ensuring optimal mitochondrial translation and assembly of oxidative phosphorylation complexes that are critical for sustaining tumor growth. The TOP1MT genomic signature profile, based on Top1mt-KO liver cancers, is correlated with enhanced survival of hepatocellular carcinoma patients. Our results highlight the importance of TOP1MT for tumor development, providing a potential rationale to develop TOP1MT-targeted drugs as anticancer therapies.
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MESH Headings
- Animals
- Carcinogenesis/pathology
- Carcinogens/toxicity
- Carcinoma, Hepatocellular/genetics
- Carcinoma, Hepatocellular/metabolism
- Carcinoma, Hepatocellular/mortality
- Carcinoma, Hepatocellular/pathology
- Cell Nucleus/metabolism
- Cell Proliferation
- DNA Topoisomerases, Type I/genetics
- DNA Topoisomerases, Type I/metabolism
- DNA, Mitochondrial/genetics
- DNA, Mitochondrial/isolation & purification
- Datasets as Topic
- Energy Metabolism
- Female
- Fibroblasts
- Gene Expression Profiling
- Gene Expression Regulation, Neoplastic
- Glycolysis
- HCT116 Cells
- Humans
- Liver/cytology
- Liver/metabolism
- Liver/pathology
- Liver Neoplasms/genetics
- Liver Neoplasms/metabolism
- Liver Neoplasms/mortality
- Liver Neoplasms/pathology
- Liver Neoplasms, Experimental/chemically induced
- Liver Neoplasms, Experimental/genetics
- Liver Neoplasms, Experimental/metabolism
- Liver Neoplasms, Experimental/pathology
- Male
- Mice
- Mice, Knockout
- Mice, Nude
- Mitochondria/metabolism
- Mitochondria/pathology
- Prognosis
- Protein Biosynthesis
- Survival Analysis
- Xenograft Model Antitumor Assays
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Affiliation(s)
- S A Baechler
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, NIH, National Cancer Institute, Bethesda, Maryland, 20892, USA
| | - V M Factor
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, NIH, National Cancer Institute, Bethesda, Maryland, 20892, USA
| | - I Dalla Rosa
- Department of Clinical and Movement Neurosciences, Institute of Neurology, Royal Free Campus, University College London, London, NW3 2PF, UK
| | - A Ravji
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, NIH, National Cancer Institute, Bethesda, Maryland, 20892, USA
| | - D Becker
- Department of Medicine I, Johannes Gutenberg University, Langenbeckstrasse 1, 55131, Mainz, Germany
| | - S Khiati
- Equipe MitoLab, Institut MitoVasc, UMR CNRS 6015, INSERM U1083, Universite d'Angers, 49933, Angers, France
| | - L M Miller Jenkins
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - M Lang
- Urologic Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MA, 20892, USA
| | - C Sourbier
- Urologic Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MA, 20892, USA
- Laboratory of Molecular Oncology, Division of Biotechnology Review and Research I, Office of Biotechnology Products, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, MD, 20993, USA
| | - S A Michaels
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, NIH, National Cancer Institute, Bethesda, Maryland, 20892, USA
| | - L M Neckers
- Urologic Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MA, 20892, USA
| | - H L Zhang
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, NIH, National Cancer Institute, Bethesda, Maryland, 20892, USA
| | - A Spinazzola
- Department of Clinical and Movement Neurosciences, Institute of Neurology, Royal Free Campus, University College London, London, NW3 2PF, UK
| | - S N Huang
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, NIH, National Cancer Institute, Bethesda, Maryland, 20892, USA
| | - J U Marquardt
- Department of Medicine I, Johannes Gutenberg University, Langenbeckstrasse 1, 55131, Mainz, Germany
| | - Y Pommier
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, NIH, National Cancer Institute, Bethesda, Maryland, 20892, USA.
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Marinello J, Delcuratolo M, Capranico G. Anthracyclines as Topoisomerase II Poisons: From Early Studies to New Perspectives. Int J Mol Sci 2018; 19:ijms19113480. [PMID: 30404148 PMCID: PMC6275052 DOI: 10.3390/ijms19113480] [Citation(s) in RCA: 141] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Revised: 11/01/2018] [Accepted: 11/05/2018] [Indexed: 12/22/2022] Open
Abstract
Mammalian DNA topoisomerases II are targets of anticancer anthracyclines that act by stabilizing enzyme-DNA complexes wherein DNA strands are cut and covalently linked to the protein. This molecular mechanism is the molecular basis of anthracycline anticancer activity as well as the toxic effects such as cardiomyopathy and induction of secondary cancers. Even though anthracyclines have been used in the clinic for more than 50 years for solid and blood cancers, the search of breakthrough analogs has substantially failed. The recent developments of personalized medicine, availability of individual genomic information, and immune therapy are expected to change significantly human cancer therapy. Here, we discuss the knowledge of anthracyclines as Topoisomerase II poisons, their molecular and cellular effects and toxicity along with current efforts to improve the therapeutic index. Then, we discuss the contribution of the immune system in the anticancer activity of anthracyclines, and the need to increase our knowledge of molecular mechanisms connecting the drug targets to the immune stimulatory pathways in cancer cells. We propose that the complete definition of the molecular interaction of anthracyclines with the immune system may open up more effective and safer ways to treat patients with these drugs.
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Affiliation(s)
- Jessica Marinello
- Department of Pharmacy and Biotechnology, University of Bologna, via Selmi 3, 40126 Bologna, Italy.
| | - Maria Delcuratolo
- Department of Pharmacy and Biotechnology, University of Bologna, via Selmi 3, 40126 Bologna, Italy.
| | - Giovanni Capranico
- Department of Pharmacy and Biotechnology, University of Bologna, via Selmi 3, 40126 Bologna, Italy.
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42
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Hangas A, Aasumets K, Kekäläinen NJ, Paloheinä M, Pohjoismäki JL, Gerhold JM, Goffart S. Ciprofloxacin impairs mitochondrial DNA replication initiation through inhibition of Topoisomerase 2. Nucleic Acids Res 2018; 46:9625-9636. [PMID: 30169847 PMCID: PMC6182158 DOI: 10.1093/nar/gky793] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 08/21/2018] [Accepted: 08/23/2018] [Indexed: 11/17/2022] Open
Abstract
Maintenance of topological homeostasis is vital for gene expression and genome replication in all organisms. Similar to other circular genomes, also mitochondrial DNA (mtDNA) is known to exist in various different topological forms, although their functional significance remains unknown. We report here that both known type II topoisomerases Top2α and Top2β are present in mammalian mitochondria, with especially Top2β regulating the supercoiling state of mtDNA. Loss of Top2β or its inhibition by ciprofloxacin results in accumulation of positively supercoiled mtDNA, followed by cessation of mitochondrial transcription and replication initiation, causing depletion of mtDNA copy number. These mitochondrial effects block both cell proliferation and differentiation, possibly explaining some of the side effects associated with fluoroquinolone antibiotics. Our results show for the first time the importance of topology for maintenance of mtDNA homeostasis and provide novel insight into the mitochondrial effects of fluoroquinolones.
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Affiliation(s)
- Anu Hangas
- Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 111, FI-80101 Joensuu, Finland
| | - Koit Aasumets
- Institute of Technology, University of Tartu, Nooruse 1, 50411 Tartu, Estonia
| | - Nina J Kekäläinen
- Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 111, FI-80101 Joensuu, Finland
| | - Mika Paloheinä
- Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 111, FI-80101 Joensuu, Finland
| | - Jaakko L Pohjoismäki
- Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 111, FI-80101 Joensuu, Finland
| | - Joachim M Gerhold
- Institute of Technology, University of Tartu, Nooruse 1, 50411 Tartu, Estonia
| | - Steffi Goffart
- Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 111, FI-80101 Joensuu, Finland
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43
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Lee RG, Sedghi M, Salari M, Shearwood AMJ, Stentenbach M, Kariminejad A, Goullee H, Rackham O, Laing NG, Tajsharghi H, Filipovska A. Early-onset Parkinson disease caused by a mutation in CHCHD2 and mitochondrial dysfunction. NEUROLOGY-GENETICS 2018; 4:e276. [PMID: 30338296 PMCID: PMC6186023 DOI: 10.1212/nxg.0000000000000276] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 06/18/2018] [Indexed: 01/01/2023]
Abstract
Objective Our goal was to identify the gene(s) associated with an early-onset form of Parkinson disease (PD) and the molecular defects associated with this mutation. Methods We combined whole-exome sequencing and functional genomics to identify the genes associated with early-onset PD. We used fluorescence microscopy, cell, and mitochondrial biology measurements to identify the molecular defects resulting from the identified mutation. Results Here, we report an association of a homozygous variant in CHCHD2, encoding coiled-coil-helix-coiled-coil-helix domain containing protein 2, a mitochondrial protein of unknown function, with an early-onset form of PD in a 26-year-old Caucasian woman. The CHCHD2 mutation in PD patient fibroblasts causes fragmentation of the mitochondrial reticular morphology and results in reduced oxidative phosphorylation at complex I and complex IV. Although patient cells could maintain a proton motive force, reactive oxygen species production was increased, which correlated with an increased metabolic rate. Conclusions Our findings implicate CHCHD2 in the pathogenesis of recessive early-onset PD, expanding the repertoire of mitochondrial proteins that play a direct role in this disease.
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Affiliation(s)
- Richard G Lee
- Centre for Medical Research (R.G.L., A.-M.J.S., M. Stentenbach, H.G., O.R., N.G.L., H.T., A.F.), University of Western Australia and the Harry Perkins Institute for Medical Research, Nedlands, Western Australia, Australia; Department of Genetics (M. Sedghi), University of Isfahan, Isfahan; Functional Neurosurgery Research Center (M. Salari), Shohada Tajrish Neurosurgical Center of Excellence, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Kariminejad-Najmabadi Pathology and Genetics Center (A.K.), Tehran, Iran; School of Molecular Sciences (O.R., A.F.), The University of Western Australia, Crawley; Department of Diagnostic Genomics (N.G.L.), PathWest, QEII Medical Centre, Nedlands, Western Australia, Australia; and Division Biomedicine and Public Health (H.T.), School of Health and Education, University of Skovde, Sweden
| | - Maryam Sedghi
- Centre for Medical Research (R.G.L., A.-M.J.S., M. Stentenbach, H.G., O.R., N.G.L., H.T., A.F.), University of Western Australia and the Harry Perkins Institute for Medical Research, Nedlands, Western Australia, Australia; Department of Genetics (M. Sedghi), University of Isfahan, Isfahan; Functional Neurosurgery Research Center (M. Salari), Shohada Tajrish Neurosurgical Center of Excellence, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Kariminejad-Najmabadi Pathology and Genetics Center (A.K.), Tehran, Iran; School of Molecular Sciences (O.R., A.F.), The University of Western Australia, Crawley; Department of Diagnostic Genomics (N.G.L.), PathWest, QEII Medical Centre, Nedlands, Western Australia, Australia; and Division Biomedicine and Public Health (H.T.), School of Health and Education, University of Skovde, Sweden
| | - Mehri Salari
- Centre for Medical Research (R.G.L., A.-M.J.S., M. Stentenbach, H.G., O.R., N.G.L., H.T., A.F.), University of Western Australia and the Harry Perkins Institute for Medical Research, Nedlands, Western Australia, Australia; Department of Genetics (M. Sedghi), University of Isfahan, Isfahan; Functional Neurosurgery Research Center (M. Salari), Shohada Tajrish Neurosurgical Center of Excellence, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Kariminejad-Najmabadi Pathology and Genetics Center (A.K.), Tehran, Iran; School of Molecular Sciences (O.R., A.F.), The University of Western Australia, Crawley; Department of Diagnostic Genomics (N.G.L.), PathWest, QEII Medical Centre, Nedlands, Western Australia, Australia; and Division Biomedicine and Public Health (H.T.), School of Health and Education, University of Skovde, Sweden
| | - Anne-Marie J Shearwood
- Centre for Medical Research (R.G.L., A.-M.J.S., M. Stentenbach, H.G., O.R., N.G.L., H.T., A.F.), University of Western Australia and the Harry Perkins Institute for Medical Research, Nedlands, Western Australia, Australia; Department of Genetics (M. Sedghi), University of Isfahan, Isfahan; Functional Neurosurgery Research Center (M. Salari), Shohada Tajrish Neurosurgical Center of Excellence, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Kariminejad-Najmabadi Pathology and Genetics Center (A.K.), Tehran, Iran; School of Molecular Sciences (O.R., A.F.), The University of Western Australia, Crawley; Department of Diagnostic Genomics (N.G.L.), PathWest, QEII Medical Centre, Nedlands, Western Australia, Australia; and Division Biomedicine and Public Health (H.T.), School of Health and Education, University of Skovde, Sweden
| | - Maike Stentenbach
- Centre for Medical Research (R.G.L., A.-M.J.S., M. Stentenbach, H.G., O.R., N.G.L., H.T., A.F.), University of Western Australia and the Harry Perkins Institute for Medical Research, Nedlands, Western Australia, Australia; Department of Genetics (M. Sedghi), University of Isfahan, Isfahan; Functional Neurosurgery Research Center (M. Salari), Shohada Tajrish Neurosurgical Center of Excellence, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Kariminejad-Najmabadi Pathology and Genetics Center (A.K.), Tehran, Iran; School of Molecular Sciences (O.R., A.F.), The University of Western Australia, Crawley; Department of Diagnostic Genomics (N.G.L.), PathWest, QEII Medical Centre, Nedlands, Western Australia, Australia; and Division Biomedicine and Public Health (H.T.), School of Health and Education, University of Skovde, Sweden
| | - Ariana Kariminejad
- Centre for Medical Research (R.G.L., A.-M.J.S., M. Stentenbach, H.G., O.R., N.G.L., H.T., A.F.), University of Western Australia and the Harry Perkins Institute for Medical Research, Nedlands, Western Australia, Australia; Department of Genetics (M. Sedghi), University of Isfahan, Isfahan; Functional Neurosurgery Research Center (M. Salari), Shohada Tajrish Neurosurgical Center of Excellence, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Kariminejad-Najmabadi Pathology and Genetics Center (A.K.), Tehran, Iran; School of Molecular Sciences (O.R., A.F.), The University of Western Australia, Crawley; Department of Diagnostic Genomics (N.G.L.), PathWest, QEII Medical Centre, Nedlands, Western Australia, Australia; and Division Biomedicine and Public Health (H.T.), School of Health and Education, University of Skovde, Sweden
| | - Hayley Goullee
- Centre for Medical Research (R.G.L., A.-M.J.S., M. Stentenbach, H.G., O.R., N.G.L., H.T., A.F.), University of Western Australia and the Harry Perkins Institute for Medical Research, Nedlands, Western Australia, Australia; Department of Genetics (M. Sedghi), University of Isfahan, Isfahan; Functional Neurosurgery Research Center (M. Salari), Shohada Tajrish Neurosurgical Center of Excellence, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Kariminejad-Najmabadi Pathology and Genetics Center (A.K.), Tehran, Iran; School of Molecular Sciences (O.R., A.F.), The University of Western Australia, Crawley; Department of Diagnostic Genomics (N.G.L.), PathWest, QEII Medical Centre, Nedlands, Western Australia, Australia; and Division Biomedicine and Public Health (H.T.), School of Health and Education, University of Skovde, Sweden
| | - Oliver Rackham
- Centre for Medical Research (R.G.L., A.-M.J.S., M. Stentenbach, H.G., O.R., N.G.L., H.T., A.F.), University of Western Australia and the Harry Perkins Institute for Medical Research, Nedlands, Western Australia, Australia; Department of Genetics (M. Sedghi), University of Isfahan, Isfahan; Functional Neurosurgery Research Center (M. Salari), Shohada Tajrish Neurosurgical Center of Excellence, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Kariminejad-Najmabadi Pathology and Genetics Center (A.K.), Tehran, Iran; School of Molecular Sciences (O.R., A.F.), The University of Western Australia, Crawley; Department of Diagnostic Genomics (N.G.L.), PathWest, QEII Medical Centre, Nedlands, Western Australia, Australia; and Division Biomedicine and Public Health (H.T.), School of Health and Education, University of Skovde, Sweden
| | - Nigel G Laing
- Centre for Medical Research (R.G.L., A.-M.J.S., M. Stentenbach, H.G., O.R., N.G.L., H.T., A.F.), University of Western Australia and the Harry Perkins Institute for Medical Research, Nedlands, Western Australia, Australia; Department of Genetics (M. Sedghi), University of Isfahan, Isfahan; Functional Neurosurgery Research Center (M. Salari), Shohada Tajrish Neurosurgical Center of Excellence, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Kariminejad-Najmabadi Pathology and Genetics Center (A.K.), Tehran, Iran; School of Molecular Sciences (O.R., A.F.), The University of Western Australia, Crawley; Department of Diagnostic Genomics (N.G.L.), PathWest, QEII Medical Centre, Nedlands, Western Australia, Australia; and Division Biomedicine and Public Health (H.T.), School of Health and Education, University of Skovde, Sweden
| | - Homa Tajsharghi
- Centre for Medical Research (R.G.L., A.-M.J.S., M. Stentenbach, H.G., O.R., N.G.L., H.T., A.F.), University of Western Australia and the Harry Perkins Institute for Medical Research, Nedlands, Western Australia, Australia; Department of Genetics (M. Sedghi), University of Isfahan, Isfahan; Functional Neurosurgery Research Center (M. Salari), Shohada Tajrish Neurosurgical Center of Excellence, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Kariminejad-Najmabadi Pathology and Genetics Center (A.K.), Tehran, Iran; School of Molecular Sciences (O.R., A.F.), The University of Western Australia, Crawley; Department of Diagnostic Genomics (N.G.L.), PathWest, QEII Medical Centre, Nedlands, Western Australia, Australia; and Division Biomedicine and Public Health (H.T.), School of Health and Education, University of Skovde, Sweden
| | - Aleksandra Filipovska
- Centre for Medical Research (R.G.L., A.-M.J.S., M. Stentenbach, H.G., O.R., N.G.L., H.T., A.F.), University of Western Australia and the Harry Perkins Institute for Medical Research, Nedlands, Western Australia, Australia; Department of Genetics (M. Sedghi), University of Isfahan, Isfahan; Functional Neurosurgery Research Center (M. Salari), Shohada Tajrish Neurosurgical Center of Excellence, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Kariminejad-Najmabadi Pathology and Genetics Center (A.K.), Tehran, Iran; School of Molecular Sciences (O.R., A.F.), The University of Western Australia, Crawley; Department of Diagnostic Genomics (N.G.L.), PathWest, QEII Medical Centre, Nedlands, Western Australia, Australia; and Division Biomedicine and Public Health (H.T.), School of Health and Education, University of Skovde, Sweden
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44
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van Esveld SL, Huynen MA. Does mitochondrial DNA evolution in metazoa drive the origin of new mitochondrial proteins? IUBMB Life 2018; 70:1240-1250. [PMID: 30281911 DOI: 10.1002/iub.1940] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Revised: 08/14/2018] [Accepted: 08/21/2018] [Indexed: 01/10/2023]
Abstract
Most eukaryotic cells contain mitochondria with a genome that evolved from their α-proteobacterial ancestor. In the course of eukaryotic evolution, the mitochondrial genome underwent a dramatic reduction in size, caused by the loss and translocation of genes. This required adjustments in mitochondrial gene expression mechanisms and resulted in a complex collaborative system of mitochondrially encoded transfer RNAs and ribosomal RNAs with nuclear encoded proteins to express the mitochondrial encoded oxidative phosphorylation (OXPHOS) proteins. In this review, we examine mitochondrial gene expression from an evolutionary point of view: to what extent can we correlate changes in the mitochondrial genome in the evolutionary lineage leading to human with the origin of new nuclear encoded proteins. We dated the evolutionary origin of mitochondrial proteins that interact with mitochondrial DNA or its RNA and/or protein products in a systematic manner and compared them with documented changes in the mitochondrial DNA. We find anecdotal but accumulating evidence that metazoan RNA-interacting proteins arose in conjunction with changes of the mitochondrial DNA. We find no substantial evidence for such compensatory evolution in new OXPHOS proteins, which appear to be constrained by the ability to form supercomplexes. © 2018 IUBMB Life, 70(12):1240-1250, 2018.
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Affiliation(s)
- S L van Esveld
- Radboud Center for Mitochondrial Medicine, Radboudumc, Nijmegen, The Netherlands.,Centre for Molecular and Biomolecular Informatics, Radboud Institute for Molecular Life Sciences, Radboudumc, Nijmegen, The Netherlands
| | - M A Huynen
- Radboud Center for Mitochondrial Medicine, Radboudumc, Nijmegen, The Netherlands
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45
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Austin CA, Lee KC, Swan RL, Khazeem MM, Manville CM, Cridland P, Treumann A, Porter A, Morris NJ, Cowell IG. TOP2B: The First Thirty Years. Int J Mol Sci 2018; 19:ijms19092765. [PMID: 30223465 PMCID: PMC6163646 DOI: 10.3390/ijms19092765] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 09/07/2018] [Accepted: 09/11/2018] [Indexed: 12/19/2022] Open
Abstract
Type II DNA topoisomerases (EC 5.99.1.3) are enzymes that catalyse topological changes in DNA in an ATP dependent manner. Strand passage reactions involve passing one double stranded DNA duplex (transported helix) through a transient enzyme-bridged break in another (gated helix). This activity is required for a range of cellular processes including transcription. Vertebrates have two isoforms: topoisomerase IIα and β. Topoisomerase IIβ was first reported in 1987. Here we review the research on DNA topoisomerase IIβ over the 30 years since its discovery.
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Affiliation(s)
- Caroline A Austin
- Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, UK.
| | - Ka C Lee
- Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, UK.
| | - Rebecca L Swan
- Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, UK.
| | - Mushtaq M Khazeem
- Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, UK.
| | - Catriona M Manville
- Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, UK.
| | - Peter Cridland
- Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, UK.
| | - Achim Treumann
- NUPPA, Newcastle University, Newcastle upon Tyne NE2 4HH, UK.
| | - Andrew Porter
- NUPPA, Newcastle University, Newcastle upon Tyne NE2 4HH, UK.
| | - Nick J Morris
- School of Biomedical Sciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, UK.
| | - Ian G Cowell
- Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, UK.
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Nicholls TJ, Gustafsson CM. Separating and Segregating the Human Mitochondrial Genome. Trends Biochem Sci 2018; 43:869-881. [PMID: 30224181 DOI: 10.1016/j.tibs.2018.08.007] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 08/21/2018] [Accepted: 08/22/2018] [Indexed: 12/17/2022]
Abstract
Cells contain thousands of copies of the mitochondrial genome. These genomes are distributed within the tubular mitochondrial network, which is itself spread across the cytosol of the cell. Mitochondrial DNA (mtDNA) replication occurs throughout the cell cycle and ensures that cells maintain a sufficient number of mtDNA copies. At replication termination the genomes must be resolved and segregated within the mitochondrial network. Defects in mtDNA replication and segregation are a cause of human mitochondrial disease associated with failure of cellular energy production. This review focuses upon recent developments on how mitochondrial genomes are physically separated at the end of DNA replication, and how these genomes are subsequently segregated and distributed around the mitochondrial network.
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Affiliation(s)
- Thomas J Nicholls
- Department of Medical Biochemistry and Cell Biology, University of Gothenburg, PO Box 440, SE-405 30 Gothenburg, Sweden.
| | - Claes M Gustafsson
- Department of Medical Biochemistry and Cell Biology, University of Gothenburg, PO Box 440, SE-405 30 Gothenburg, Sweden
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47
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LeMaire SA, Zhang L, Luo W, Ren P, Azares AR, Wang Y, Zhang C, Coselli JS, Shen YH. Effect of Ciprofloxacin on Susceptibility to Aortic Dissection and Rupture in Mice. JAMA Surg 2018; 153:e181804. [PMID: 30046809 PMCID: PMC6233654 DOI: 10.1001/jamasurg.2018.1804] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 04/22/2018] [Indexed: 12/12/2022]
Abstract
Importance Fluoroquinolones are among the most commonly prescribed antibiotics. Recent clinical studies indicated an association between fluoroquinolone use and increased risk of aortic aneurysm and dissection (AAD). This alarming association has raised concern, especially in patients with AAD with risk of rupture and in individuals at risk for developing AAD. Objective To examine the effect of ciprofloxacin on AAD development in mice. Design, Setting, and Participants In a mouse model of moderate, sporadic AAD, 4-week-old male and female C57BL/6J mice were challenged with a high-fat diet and low-dose angiotensin infusion (1000 ng/min/kg). Control unchallenged mice were fed a normal diet and infused with saline. After randomization, challenged and unchallenged mice received ciprofloxacin (100 mg/kg/d) or vehicle through daily gavage during angiotensin or saline infusion. Aortic aneurysm and dissection development and aortic destruction were compared between mice. The direct effects of ciprofloxacin on aortic smooth muscle cells were examined in cultured cells. Results No notable aortic destruction was observed in unchallenged mice that received ciprofloxacin alone. Aortic challenge induced moderate aortic destruction with development of AAD in 17 of 38 mice (45%) and severe AAD in 9 (24%) but no rupture or death. However, challenged mice that received ciprofloxacin had severe aortic destruction and a significantly increased incidence of AAD (38 of 48 [79%]; P = .001; χ2 = 10.9), severe AAD (32 of 48 [67%]; P < .001; χ2 = 15.7), and rupture and premature death (7 of 48 [15%]; P = .01; χ2 = 6.0). The increased AAD incidence was observed in different aortic segments and was similar between male and female mice. Compared with aortic tissues from challenged control mice, those from challenged mice that received ciprofloxacin showed decreased expression of lysyl oxidase, an enzyme that is critical in the assembly and stabilization of elastic fibers and collagen. These aortas also showed increased matrix metalloproteinase levels and activity, elastic fiber fragmentation, and aortic cell injury. In cultured smooth muscle cells, ciprofloxacin treatment significantly reduced lysyl oxidase expression and activity, increased matrix metalloproteinase expression and activity, suppressed cell proliferation, and induced cell death. Furthermore, ciprofloxacin-a DNA topoisomerase inhibitor-caused nuclear and mitochondrial DNA damage and the release of DNA into the cytosol, subsequently inducing mitochondrial dysfunction, reactive oxygen species production, and activation of the cytosolic DNA sensor STING, which we further showed was involved in the suppression of lysyl oxidase expression and induction of matrix metalloproteinase expression. Conclusions and Relevance Ciprofloxacin increases susceptibility to aortic dissection and rupture in a mouse model of moderate, sporadic AAD. Ciprofloxacin should be used with caution in patients with aortic dilatation, as well as in those at high risk for AAD.
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Affiliation(s)
- Scott A. LeMaire
- Division of Cardiothoracic Surgery, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, Texas
- Department of Cardiovascular Surgery, Texas Heart Institute, Houston
- Cardiovascular Research Institute, Baylor College of Medicine, Houston, Texas
| | - Lin Zhang
- Division of Cardiothoracic Surgery, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, Texas
- Department of Cardiovascular Surgery, Texas Heart Institute, Houston
| | - Wei Luo
- Division of Cardiothoracic Surgery, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, Texas
- Department of Cardiovascular Surgery, Texas Heart Institute, Houston
| | - Pingping Ren
- Division of Cardiothoracic Surgery, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, Texas
- Department of Cardiovascular Surgery, Texas Heart Institute, Houston
| | | | - Yidan Wang
- Division of Cardiothoracic Surgery, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, Texas
- Department of Cardiovascular Surgery, Texas Heart Institute, Houston
| | - Chen Zhang
- Division of Cardiothoracic Surgery, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, Texas
- Department of Cardiovascular Surgery, Texas Heart Institute, Houston
| | - Joseph S. Coselli
- Division of Cardiothoracic Surgery, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, Texas
- Department of Cardiovascular Surgery, Texas Heart Institute, Houston
- Cardiovascular Research Institute, Baylor College of Medicine, Houston, Texas
| | - Ying H. Shen
- Division of Cardiothoracic Surgery, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, Texas
- Department of Cardiovascular Surgery, Texas Heart Institute, Houston
- Cardiovascular Research Institute, Baylor College of Medicine, Houston, Texas
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48
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Mitochondrial DNA replication in mammalian cells: overview of the pathway. Essays Biochem 2018; 62:287-296. [PMID: 29880722 PMCID: PMC6056714 DOI: 10.1042/ebc20170100] [Citation(s) in RCA: 100] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 05/18/2018] [Accepted: 05/21/2018] [Indexed: 12/27/2022]
Abstract
Mammalian mitochondria contain multiple copies of a circular, double-stranded DNA genome and a dedicated DNA replication machinery is required for its maintenance. Many disease-causing mutations affect mitochondrial replication factors and a detailed understanding of the replication process may help to explain the pathogenic mechanisms underlying a number of mitochondrial diseases. We here give a brief overview of DNA replication in mammalian mitochondria, describing our current understanding of this process and some unanswered questions remaining.
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Huang SYN, Dalla Rosa I, Michaels SA, Tulumello DV, Agama K, Khiati S, Jean SR, Baechler SA, Factor VM, Varma S, Murai J, Miller Jenkins LM, Kelley SO, Pommier Y. Mitochondrial tyrosyl-DNA phosphodiesterase 2 and its TDP2 S short isoform. EMBO Rep 2018; 19:embr.201642139. [PMID: 29438979 DOI: 10.15252/embr.201642139] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Revised: 12/04/2017] [Accepted: 01/05/2018] [Indexed: 12/26/2022] Open
Abstract
Tyrosyl-DNA phosphodiesterase 2 (TDP2) repairs abortive topoisomerase II cleavage complexes. Here, we identify a novel short isoform of TDP2 (TDP2S) expressed from an alternative transcription start site. TDP2S contains a mitochondrial targeting sequence, contributing to its enrichment in the mitochondria and cytosol, while full-length TDP2 contains a nuclear localization signal and the ubiquitin-associated domain in the N-terminus. Our study reveals that both TDP2 isoforms are present and active in the mitochondria. Comparison of isogenic wild-type (WT) and TDP2 knockout (TDP2-/-/-) DT40 cells shows that TDP2-/-/- cells are hypersensitive to mitochondrial-targeted doxorubicin (mtDox), and that complementing TDP2-/-/- cells with human TDP2 restores resistance to mtDox. Furthermore, mtDox selectively depletes mitochondrial DNA in TDP2-/-/- cells. Using CRISPR-engineered human cells expressing only the TDP2S isoform, we show that TDP2S also protects human cells against mtDox. Finally, lack of TDP2 in the mitochondria reduces the mitochondria transcription levels in two different human cell lines. In addition to identifying a novel TDP2S isoform, our report demonstrates the presence and importance of both TDP2 isoforms in the mitochondria.
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Affiliation(s)
- Shar-Yin N Huang
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Ilaria Dalla Rosa
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Stephanie A Michaels
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
| | - David V Tulumello
- Department of Biochemistry, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Keli Agama
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Salim Khiati
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Sae Rin Jean
- Department of Biochemistry, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Simone A Baechler
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Valentina M Factor
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Sudhir Varma
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Junko Murai
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Lisa M Miller Jenkins
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Shana O Kelley
- Department of Biochemistry, Faculty of Medicine, University of Toronto, Toronto, ON, Canada.,Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON, Canada
| | - Yves Pommier
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
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50
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Delgado JL, Hsieh CM, Chan NL, Hiasa H. Topoisomerases as anticancer targets. Biochem J 2018; 475:373-398. [PMID: 29363591 PMCID: PMC6110615 DOI: 10.1042/bcj20160583] [Citation(s) in RCA: 266] [Impact Index Per Article: 44.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Revised: 12/14/2017] [Accepted: 12/21/2017] [Indexed: 12/15/2022]
Abstract
Many cancer type-specific anticancer agents have been developed and significant advances have been made toward precision medicine in cancer treatment. However, traditional or nonspecific anticancer drugs are still important for the treatment of many cancer patients whose cancers either do not respond to or have developed resistance to cancer-specific anticancer agents. DNA topoisomerases, especially type IIA topoisomerases, are proved therapeutic targets of anticancer and antibacterial drugs. Clinically successful topoisomerase-targeting anticancer drugs act through topoisomerase poisoning, which leads to replication fork arrest and double-strand break formation. Unfortunately, this unique mode of action is associated with the development of secondary cancers and cardiotoxicity. Structures of topoisomerase-drug-DNA ternary complexes have revealed the exact binding sites and mechanisms of topoisomerase poisons. Recent advances in the field have suggested a possibility of designing isoform-specific human topoisomerase II poisons, which may be developed as safer anticancer drugs. It may also be possible to design catalytic inhibitors of topoisomerases by targeting certain inactive conformations of these enzymes. Furthermore, identification of various new bacterial topoisomerase inhibitors and regulatory proteins may inspire the discovery of novel human topoisomerase inhibitors. Thus, topoisomerases remain as important therapeutic targets of anticancer agents.
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Affiliation(s)
- Justine L Delgado
- Division of Medicinal and Natural Products Chemistry, Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, 115 S Grand Ave., S321 Pharmacy Building, Iowa City, IA 52242, U.S.A
| | - Chao-Ming Hsieh
- Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, Taipei City 100, Taiwan
| | - Nei-Li Chan
- Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, Taipei City 100, Taiwan
| | - Hiroshi Hiasa
- Department of Pharmacology, University of Minnesota Medical School, 6-120 Jackson Hall, 321 Church Street SE, Minneapolis, MN 55455, U.S.A.
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