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Chowdhury SR, Bhoumik A, Gupta VK, Majumder HK. Type II DNA Topoisomerases in trypanosomatid and apicomplexan parasites. Acta Trop 2022; 234:106613. [PMID: 35905776 DOI: 10.1016/j.actatropica.2022.106613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Revised: 07/14/2022] [Accepted: 07/18/2022] [Indexed: 11/01/2022]
Abstract
Diseases caused by trypanosomatid parasites have no commercially available vaccines for human application. Treatment modalities completely rely on chemotherapeutics strategies that often exhibit clinical drawbacks, like host toxicity, side effects and treatment failure for drug resistance. These, in many instances, are costly, making them unaffordable for certain groups of beneficiaries. To find reasonable solutions, researchers are attempting to identify and validate new drug targets that would offer parasite specificity. DNA topoisomerases in parasites present a consolidated class of drug targets due to their multiple structural and functional differences with host homologs. Type II DNA topoisomerases in these parasites, in particular, have been attracting interest of scientific community attributable to their pivotal role in the replication of the atypical DNA. In this article, we present a detailed review of structural and functional features of type II DNA topoisomerases of clinically-relevant trypanosomatid and apicomplexan parasites. Also, we provide up-to-date information on different molecules that target these enzymes. Altogether, the review will largely help in understanding the rationale for exploiting type II DNA topoisomerases in these groups of parasites as drug targets.
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Affiliation(s)
- Somenath Roy Chowdhury
- Institut für Physikalische Chemie, Westfälische Wilhelms-Universität Münster, Correnstrasse 28, 48149, Münster.
| | - Arpita Bhoumik
- Infectious Diseases & Immunology Division, CSIR-Indian Institute of Chemical Biology, Kolkata, 700 032
| | - Vivek Kumar Gupta
- Organic and Medicinal Chemistry Division, CSIR-Indian Institute of Chemical Biology, Kolkata 700 032
| | - Hemanta K Majumder
- Infectious Diseases & Immunology Division, CSIR-Indian Institute of Chemical Biology, Kolkata, 700 032
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2
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Lamba S, Roy A. DNA Topoisomerases in the Unicellular Protozoan Parasites: Unwinding the Mystery. Biochem Pharmacol 2022; 203:115158. [PMID: 35780829 DOI: 10.1016/j.bcp.2022.115158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 06/17/2022] [Accepted: 06/27/2022] [Indexed: 11/28/2022]
Abstract
DNA topoisomerases are a group of enzymes present ubiquitously in all organisms from unicellular protozoan parasites to humans. These enzymes control the topological problems caused by DNA double helix in the cell during nucleic acid metabolism. Certain types of topoisomerases present in unicellular parasites are quite different from human topoisomerases (hTop) concerning structure, expression, and function. Many protozoan parasites causing fatal diseases have DNA topoisomerases, which play vital roles in their survival. Given the fact that the structures of the protozoan parasite topoisomerases are different from humans, DNA topoisomerase acts as an essential target for potent drug development for parasitic diseases. Moreover, various studies revealed the therapeutic potential of these drugs targeting the parasitic topoisomerases. Therefore, the characterization of parasitic topoisomerases is pivotal for the development of future potential drug targets. Considering the importance of this ubiquitous enzyme as a potential drug target, we describe in detail all the reported protozoan topoisomerases in an organized manner including Leishmania, Trypanosoma, Plasmodium, Giardia, Entamoeba, Babesia, Theileria, Crithidia, Cryptosporidium, Toxoplasma, etc. This review highlights the unique attributes associated with the structure and function of different types of DNA topoisomerases from the unicellular protozoan parasites. So, it would be beneficial for researchers to obtain awareness about the currently characterized topoisomerases and the ones that need better characterization, understand the structure-function relationship of parasitic topoisomerases, to develop the potent anti-parasitic drugs, and also provides a future platform for therapeutic development.
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Affiliation(s)
- Swati Lamba
- Department of Biotechnology, Savitribai Phule Pune University, Ganeshkhind Road, Pune-411007, India
| | - Amit Roy
- Department of Biotechnology, Savitribai Phule Pune University, Ganeshkhind Road, Pune-411007, India.
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3
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Varghese SS, Ghosh SK. Stress-responsive Entamoeba topoisomerase II: a potential antiamoebic target. FEBS Lett 2019; 594:1005-1020. [PMID: 31724164 DOI: 10.1002/1873-3468.13677] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 11/05/2019] [Accepted: 11/05/2019] [Indexed: 12/21/2022]
Abstract
Topoisomerases, the ubiquitous enzymes involved in all DNA processes across the biological world, are targets for various anticancer and antimicrobial agents. In Entamoeba histolytica, the causative agent of amebiasis, we found one of seven unexplored putative topoisomerases to be highly upregulated during heat shock and oxidative stress, and also during the late hours of encystation. Further analysis revealed the upregulated enzyme to be a eukaryotic type IIA topoisomerase (TopoII) with demonstrable activity in vitro. This enzyme is localized to newly forming nuclei during encystation. Gene silencing of the TopoII reduces viability and encystation efficiency. Notable susceptibility of Entamoeba TopoII to prokaryotic topoisomerase inhibitors opens up the possibility for exploring this enzyme as a new antiamoebic target.
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Affiliation(s)
- Sneha Susan Varghese
- Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur, India
| | - Sudip Kumar Ghosh
- Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur, India
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Reguera RM, Elmahallawy EK, García-Estrada C, Carbajo-Andrés R, Balaña-Fouce R. DNA Topoisomerases of Leishmania Parasites; Druggable Targets for Drug Discovery. Curr Med Chem 2019; 26:5900-5923. [DOI: 10.2174/0929867325666180518074959] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Revised: 03/15/2018] [Accepted: 05/14/2018] [Indexed: 12/13/2022]
Abstract
DNA topoisomerases (Top) are a group of isomerase enzymes responsible for controlling the topological problems caused by DNA double helix in the cell during the processes of replication, transcription and recombination. Interestingly, these enzymes have been known since long to be key molecular machines in several cellular processes through overwinding or underwinding of DNA in all living organisms. Leishmania, a trypanosomatid parasite responsible for causing fatal diseases mostly in impoverished populations of low-income countries, has a set of six classes of Top enzymes. These are placed in the nucleus and the single mitochondrion and can be deadly targets of suitable drugs. Given the fact that there are clear differences in structure and expression between parasite and host enzymes, numerous studies have reported the therapeutic potential of Top inhibitors as antileishmanial drugs. In this regard, numerous compounds have been described as Top type IB and Top type II inhibitors in Leishmania parasites, such as camptothecin derivatives, indenoisoquinolines, indeno-1,5- naphthyridines, fluoroquinolones, anthracyclines and podophyllotoxins. The aim of this review is to highlight several facts about Top and Top inhibitors as potential antileishmanial drugs, which may represent a promising strategy for the control of this disease of public health importance.
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Affiliation(s)
- Rosa M. Reguera
- Department of Biomedical Sciences, University of Leon (ULE), Leon, Spain
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de Oliveira França A, de Oliveira Ramos Pereira L, Ortiz Tanaka TS, Pereira de Oliveira M, Cavalheiros Dorval ME. Viability of Leishmania in blood donors: A tangible possibility of transfusion transmission. J Microbiol Immunol Infect 2019; 53:176-178. [PMID: 31427110 DOI: 10.1016/j.jmii.2019.06.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Revised: 04/05/2019] [Accepted: 06/20/2019] [Indexed: 01/09/2023]
Abstract
Asymptomatic individuals apparently able for blood donation, could be infected with Leishmania imposing risks for immunologically vulnerable recipients. Reverse transcribed conventional PCR targeting the 28S ribosomal subunit was conducted, in order to confirm the viability of the parasite in blood donors positive for Leishmania infection.
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Affiliation(s)
- Adriana de Oliveira França
- Laboratory of Clinical Parasitology, Graduate Program in Infectious and Parasitic Diseases, Universidade Federal de Mato Grosso do Sul, Campo Grande, MS, Brazil.
| | - Luiza de Oliveira Ramos Pereira
- Interdisciplinary Laboratory of Medical Research (LIPMed), Laboratory of Leishmaniasis Research, Instituto Oswaldo Cruz, Rio de Janeiro, RJ, Brazil
| | - Tayana Serpa Ortiz Tanaka
- Graduate Program in Infectious and Parasitic Diseases, Universidade Federal de Mato Grosso do Sul, Campo Grande, MS, Brazil
| | - Márcia Pereira de Oliveira
- Interdisciplinary Laboratory of Medical Research (LIPMed), Instituto Oswaldo Cruz, Rio de Janeiro, RJ, Brazil
| | - Maria Elizabeth Cavalheiros Dorval
- Laboratory of Clinical Parasitology, Graduate Program in Infectious and Parasitic Diseases, Universidade Federal de Mato Grosso do Sul, Campo Grande, MS, Brazil
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Balaña-Fouce R, Alvarez-Velilla R, Fernández-Prada C, García-Estrada C, Reguera RM. Trypanosomatids topoisomerase re-visited. New structural findings and role in drug discovery. Int J Parasitol Drugs Drug Resist 2014; 4:326-37. [PMID: 25516844 PMCID: PMC4266802 DOI: 10.1016/j.ijpddr.2014.07.006] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
There is an urgent need of new treatments against trypanosomatids-borne diseases. DNA topoisomerases are pointed as potential drug targets against unicellular parasites. Trypanosomatids have a full set of DNA topoisomerases in both nucleus and kinetoplast. TopII and TopIII are located in the kinetoplast and fully involved in kDNA replication. Tritryps TopIB differ in structure from mammalian’s pointing to an attractive target.
The Trypanosomatidae family, composed of unicellular parasites, causes severe vector-borne diseases that afflict human populations worldwide. Chagas disease, sleeping sickness, as well as different sorts of leishmaniases are amongst the most important infectious diseases produced by Trypanosoma cruzi, Trypanosoma brucei and Leishmania spp., respectively. All these infections are closely related to weak health care services in low-income populations of less developed and least economically developed countries. Search for new therapeutic targets in order to hit these pathogens is of paramount priority, as no effective vaccine is currently in use against any of these parasites. Furthermore, present-day chemotherapy comprises old-fashioned drugs full of important side effects. Besides, they are prone to produce tolerance and resistance as a consequence of their continuous use for decades. DNA topoisomerases (Top) are ubiquitous enzymes responsible for solving the torsional tensions caused during replication and transcription processes, as well as in maintaining genomic stability during DNA recombination. As the inhibition of these enzymes produces cell arrest and triggers cell death, Top inhibitors are among the most effective and most widely used drugs in both cancer and antibacterial therapies. Top relaxation and decatenation activities, which are based on a common nicking–closing cycle involving one or both DNA strands, have been pointed as a promising drug target. Specific inhibitors that bind to the interface of DNA-Top complexes can stabilize Top-mediated transient DNA breaks. In addition, important structural differences have been found between Tops from the Trypanosomatidae family members and Tops from the host. Such dissimilarities make these proteins very interesting for drug design and molecular intervention. The present review is a critical update of the last findings regarding trypanosomatid’s Tops, their new structural features, their involvement both in the physiology and virulence of these parasites, as well as their use as promising targets for drug discovery.
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Affiliation(s)
- Rafael Balaña-Fouce
- Departamento de Ciencias Biomédicas, Universidad de León, Campus de Vegazana s/n, 24071 León, Spain
| | - Raquel Alvarez-Velilla
- Departamento de Ciencias Biomédicas, Universidad de León, Campus de Vegazana s/n, 24071 León, Spain
| | | | - Carlos García-Estrada
- Departamento de Ciencias Biomédicas, Universidad de León, Campus de Vegazana s/n, 24071 León, Spain
| | - Rosa M Reguera
- Departamento de Ciencias Biomédicas, Universidad de León, Campus de Vegazana s/n, 24071 León, Spain
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Menna-Barreto RF, de Castro SL. The double-edged sword in pathogenic trypanosomatids: the pivotal role of mitochondria in oxidative stress and bioenergetics. Biomed Res Int 2014; 2014:614014. [PMID: 24800243 DOI: 10.1155/2014/614014] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Accepted: 02/17/2014] [Indexed: 11/17/2022]
Abstract
The pathogenic trypanosomatids Trypanosoma brucei, Trypanosoma cruzi, and Leishmania spp. are the causative agents of African trypanosomiasis, Chagas disease, and leishmaniasis, respectively. These diseases are considered to be neglected tropical illnesses that persist under conditions of poverty and are concentrated in impoverished populations in the developing world. Novel efficient and nontoxic drugs are urgently needed as substitutes for the currently limited chemotherapy. Trypanosomatids display a single mitochondrion with several peculiar features, such as the presence of different energetic and antioxidant enzymes and a specific arrangement of mitochondrial DNA (kinetoplast DNA). Due to mitochondrial differences between mammals and trypanosomatids, this organelle is an excellent candidate for drug intervention. Additionally, during trypanosomatids' life cycle, the shape and functional plasticity of their single mitochondrion undergo profound alterations, reflecting adaptation to different environments. In an uncoupling situation, the organelle produces high amounts of reactive oxygen species. However, these species role in parasite biology is still controversial, involving parasite death, cell signalling, or even proliferation. Novel perspectives on trypanosomatid-targeting chemotherapy could be developed based on better comprehension of mitochondrial oxidative regulation processes.
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Zuma AA, Cavalcanti DP, Maia MC, de Souza W, Motta MCM. Effect of topoisomerase inhibitors and DNA-binding drugs on the cell proliferation and ultrastructure of Trypanosoma cruzi. Int J Antimicrob Agents 2011; 37:449-56. [DOI: 10.1016/j.ijantimicag.2010.11.031] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2010] [Revised: 10/31/2010] [Accepted: 11/01/2010] [Indexed: 11/22/2022]
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Kapoor P, Kumar A, Naik R, Ganguli M, Siddiqi MI, Sahasrabuddhe AA, Gupta CM. Leishmania actin binds and nicks kDNA as well as inhibits decatenation activity of type II topoisomerase. Nucleic Acids Res 2010; 38:3308-17. [PMID: 20147461 PMCID: PMC2879525 DOI: 10.1093/nar/gkq051] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Leishmania actin (LdACT) is an unconventional form of eukaryotic actin in that it markedly differs from other actins in terms of its filament forming as well as toxin and DNase-1-binding properties. Besides being present in the cytoplasm, cortical regions, flagellum and nucleus, it is also present in the kinetoplast where it appears to associate with the kinetoplast DNA (kDNA). However, nothing is known about its role in this organelle. Here, we show that LdACT is indeed associated with the kDNA disc in Leishmania kinetoplast, and under in vitro conditions, it specifically binds DNA primarily through electrostatic interactions involving its unique DNase-1-binding region and the DNA major groove. We further reveal that this protein exhibits DNA-nicking activity which requires its polymeric state as well as ATP hydrolysis and through this activity it converts catenated kDNA minicircles into open form. In addition, we show that LdACT specifically binds bacterial type II topoisomerase and inhibits its decatenation activity. Together, these results strongly indicate that LdACT could play a critical role in kDNA remodeling.
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Affiliation(s)
- Prabodh Kapoor
- Division of Molecular and Structural Biology, Central Drug Research Institute, Chattar Manzil Palace, CSIR, Lucknow 226001, India
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Alcolea PJ, Alonso A, Sánchez-Gorostiaga A, Moreno-Paz M, Gómez MJ, Ramos I, Parro V, Larraga V. Genome-wide analysis reveals increased levels of transcripts related with infectivity in peanut lectin non-agglutinated promastigotes of Leishmania infantum. Genomics 2009; 93:551-64. [DOI: 10.1016/j.ygeno.2009.01.007] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2008] [Revised: 01/26/2009] [Accepted: 01/27/2009] [Indexed: 10/21/2022]
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Abstract
It was discovered 12 years ago that type IIA topoisomerases can simplify DNA topology--the steady-state fractions of knots and links created by the enzymes are many times lower than the corresponding equilibrium fractions. Though this property of the enzymes made clear biological sense, it was not clear how small enzymes could selectively change the topology of very large DNA molecules, since topology is a global property and cannot be determined by a local DNA-protein interaction. A few models, suggested to explain the phenomenon, are analyzed in this review. We also consider experimental data that both support and contravene these models.
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Wang Y, Tsai YC, Urena-Rivera E, Chen J. Expression, purification and characterization of recombinant mitochondrial topoisomerase II of kinetoplastid Crithidia fasciculata in High-five insect cells. Protein Expr Purif 2007; 58:122-31. [PMID: 18068376 DOI: 10.1016/j.pep.2007.10.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2007] [Revised: 09/19/2007] [Accepted: 10/06/2007] [Indexed: 12/01/2022]
Abstract
Topoisomerase II of kinetoplastid parasites plays an important role in the replication of unusual networks of kinetoplast DNA (kDNA) and is a very useful target for antiparasitic drugs. In this study, we cloned full-length Crithidia fasciculata mitochondrial topoisomerase II gene into pFastBac-HTc vector and successfully expressed an active recombinant full-length mitochondrial topoisomerase II in Bac-to-Bac baculovirus expression system. A rapid and simple purification strategy was established by incorporating a FLAG-tag at the C-terminus of the protein. The purified recombinant topoisomerase II showed a major single band on SDS-PAGE (>96% purity) and was verified through Western blot analysis. The recombinant full-length mitochondrial topoisomerase II exhibited decatenation, catenation and relaxation activity of type II topoisomerase as well as various sensitivities to a series of known topoisomerase inhibitors. These studies explore new way and lay groundwork to express all other similar full-length kinetoplastid topoisomerases, it will also facilitate further elucidation of X-ray structure, catalysis mechanism of kinetoplastid topoisomerases and design of new antiparasitic drugs targeting kinetoplastid topoisomerases.
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Affiliation(s)
- Yuzhen Wang
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA
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Cortázar TM, Coombs GH, Walker J. Leishmania panamensis: Comparative inhibition of nuclear DNA topoisomerase II enzymes from promastigotes and human macrophages reveals anti-parasite selectivity of fluoroquinolones, flavonoids and pentamidine. Exp Parasitol 2007; 116:475-82. [PMID: 17466980 DOI: 10.1016/j.exppara.2007.02.018] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2007] [Accepted: 02/28/2007] [Indexed: 10/23/2022]
Abstract
Certain model inhibitors exerted selective action against the catalytic activity of nuclear DNA topoisomerase II (TOPII) of Leishmania panamensis promastigotes. The second-generation fluoroquinolones enoxacin and ciprofloxacin exhibited extraordinarily high anti-parasite selectivity displaying 582- and 40-fold greater potencies against L. panamensis TOPII as compared with the human macrophage enzyme. The flavonoids quercetin and ellagic acid showed inverse specificities, the former being 161-fold more potent against L. panamensis TOPII, and the latter 15.7-fold more active against macrophage TOPII. The protoberberine coralyne was a potent inhibitor of both Leishmania and macrophage TOPII. Bis-benzimidazoles and the diamidine diminazene aceturate exhibited uniformly high potencies against parasite and host TOPII, but a second diamidine pentamidine showed 17.6-fold greater specificity for Leishmania TOPII. The antimonial sodium stibogluconate was an ineffective inhibitor of parasite TOPII showing 4.3-fold greater potency against the macrophage enzyme. These findings suggest that the leishmanicidal activities of certain fluoroquinolones and pentamidine may be mediated partly through TOPII inhibition.
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Affiliation(s)
- Tania M Cortázar
- Centro Internacional de Entrenamiento e Investigaciones Medicas, Cali, Colombia
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Abstract
Mitochondria are the only organelles containing metabolically active DNA besides nuclei. By analogy with the nuclear topoisomerases, mitochondrial topoisomerase activities are probably critical for maintaining the topology of mitochondrial DNA during replication, transcription, and repair. Mitochondrial diseases include a wide range of defects including neurodegeneracies, myopathies, metabolic abnormalities and premature aging. Vertebrates only have one known specific mitochondrial topoisomerase gene (TOP1mt), coding for a type IB topoisomerase. Like the mitochondrial DNA and RNA polymerase, the TOP1mt gene is encoded in the nuclear genome. The TOP1mt gene possesses the 13 exon Top1B signature motif and codes for a mitochondrial targeting signals at the N-terminus of the Top1mt polypeptide. This review summarizes our current knowledge of mitochondrial topoisomerases (type IA, IB and type II) in eukaryotes including budding and fission yeasts (Saccharomyces cerevisiae and Schizosaccharomyces pombe) and protozoan parasites (kinetoplastidiae and plasmodium). It also includes new data showing alternative splice variants of human TOP1mt.
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Affiliation(s)
- Hongliang Zhang
- Laboratory of Molecular Pharmacology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bldg 37, Room 5068, Bethesda, MD 20892-4255, USA
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Abstract
DNA topoisomerases are the key enzymes involved in carrying out high precision DNA transactions inside the cells. However, they are detrimental to the cell when a wide variety of topoisomerase-targeted drugs generate cytotoxic lesions by trapping the enzymes in covalent complexes on the DNA. The discovery of unusual heterodimeric topoisomerase I in kinetoplastid family added a new twist in topoisomerase research related to evolution, functional conservation and their preferential sensitivity to Camptothecin. On the other hand, structural and mechanistic studies on kinetoplastid topoisomerase II delineate some distinguishing features that differentiate the parasitic enzyme from its prokaryotic and eukaryotic counterparts. This review summarizes the recent advances in research in kinetoplastid topoisomerases, their evolutionary significance and the death of the unicellular parasite Leishmania donovani induced by topoisomerase I inhibitor camptothecin.
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Affiliation(s)
- Benu Brata Das
- Department of Molecular Parasitology, Indian Institute of Chemical Biology, Kolkata 700032, India
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Kulikowicz T, Shapiro TA. Distinct Genes Encode Type II Topoisomerases for the Nucleus and Mitochondrion in the Protozoan Parasite Trypanosoma brucei. J Biol Chem 2006; 281:3048-56. [PMID: 16316982 DOI: 10.1074/jbc.m505977200] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Topoisomerases are essential for orderly nucleic acid metabolism and cell survival and are proven targets for clinically useful antimicrobial and anticancer drugs. Interest in the topologically intricate mitochondrial DNA (kinetoplast or kDNA) of Trypanosoma brucei brucei and related kinetoplastid protozoan parasites has led to many reports of type II topoisomerases that participate in kDNA metabolism (we term the T. brucei brucei gene TbTOP2mt). We have now identified and characterized two new genes for type II topoisomerases in T. brucei brucei, termed TbTOP2alpha and TbTOP2beta. Phylogenetically, they share a common node with other nuclear topoisomerases, clearly distinct from a clade that includes the previously reported kinetoplastid genes, all of which are homologs of TbTOP2mt. Southern blot analysis reveals the new genes are single copy and positioned approximately 1.7 kb apart. Cognate mRNAs are expressed in African trypanosomes, but only a single message is detected in Leishmania or Crithidia. TbTOP2alpha encodes an ATP-dependent topoisomerase that appears as a single approximately 170-kDa band on immunoblots and localizes to the nucleus; RNA interference leads to pleomorphic nuclear (but not kDNA) abnormalities and early growth arrest. The role of TbTOP2beta is unclear. Although transcribed in trypanosomes, TbTOP2beta is not detected by beta-specific antiserum, and RNAi silencing results in no obvious phenotype. These studies indicate that African trypanosomes and related kinetoplastid human pathogens are unusual in having independent topoisomerase II genes to service their nuclear and mitochondrial genomes, and they highlight TbTOP2alpha as a promising target for the development of much-needed new therapies.
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Affiliation(s)
- Tomasz Kulikowicz
- Division of Clinical Pharmacology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
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Jean-Moreno V, Rojas R, Goyeneche D, Coombs GH, Walker J. Leishmania donovani: Differential activities of classical topoisomerase inhibitors and antileishmanials against parasite and host cells at the level of DNA topoisomerase I and in cytotoxicity assays. Exp Parasitol 2006; 112:21-30. [PMID: 16293247 DOI: 10.1016/j.exppara.2005.08.014] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2005] [Revised: 08/30/2005] [Accepted: 08/31/2005] [Indexed: 11/23/2022]
Abstract
Different classes of topoisomerase (TOP) inhibitors and antitrypanosomatid agents exhibited variable efficacies against Leishmania donovani parasites and human mononuclear cells both at the level of DNA topoisomerase I (TOPI) catalytic activity and in cytotoxicity assays. Bis-benzimidazoles and the diamidine diminazene aceturate exhibited uniformly high efficacies against parasite and host enzymes as well as against parasite and mononuclear cells, but pentamidine showed around 2 orders of magnitude greater specificity for Leishmania TOPI and amastigote cells (P<0.05). The protoberberine coralyne and the flavonoid quercetin were highly potent, but non-selective, inhibitors in vitro, although the latter showed slight selectivity for parasite TOPI. Camptothecin was selective for mononuclear cells at both levels (P<0.05) and sodium stibogluconate was selective only at the enzyme level displaying 30-fold greater potency against parasite TOPI (P<0.05). These data suggest that at least part of pentamidines' leishmanicidal activity may be mediated through TOPI inhibition, and support the feasibility of exploiting differences between Leishmania and human TOPs to develop modified compounds with improved selectivity.
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Affiliation(s)
- Valerie Jean-Moreno
- Centro Internacional de Entrenamiento e Investigaciones Médicas (CIDEIM), Biochemistry and Molecular Biology Unit, Avenida 1 Norte No. 3-03, AA 5390, Cali, Valle de Cauca, Colombia
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Mak CKM, Hung VKL, Wong JTY. Type II topoisomerase activities in both the G1 and G2/M phases of the dinoflagellate cell cycle. Chromosoma 2005; 114:420-31. [PMID: 16252092 DOI: 10.1007/s00412-005-0027-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2005] [Revised: 08/31/2005] [Accepted: 09/01/2005] [Indexed: 11/28/2022]
Abstract
Dinoflagellate genomes are large (up to 200 pg) and are encoded in histoneless chromosomes that are quasi-permanently condensed. This unique combination of chromosomal characteristics presents additional topological and cell cycle control problems for a eukaryotic cell, potentially exhibiting novel regulatory requirements of topoisomerase II. The heterotrophic dinoflagellate Crypthecodinium cohnii was used in this study. The topoisomerase II activities throughout its cell cycle were investigated by DNA flow cytometry following enzyme deactivation. Fluorescence microscopy was also used for studying the chromosome morphology of the treated cells. Two classes of topoisomerase II inhibitors were applied in our study, both of which caused G1 delay as well as G2/M arrest in the C. cohnii cell cycle. At high doses, the topoisomerase poisons amsacrine and ellipticine induced DNA fragmentation in C. cohnii cells. Topoisomerase II activities, as measured by the ability to decatenate kinetoplastid DNA (kDNA), are normally detected throughout the cell cycle in C. cohnii. Our results suggest that the requirement of type II topoisomerase activities during the G1 phase of the cell cycle may relate to the unwinding of quasi-permanently condensed chromosomes for the purpose of transcription. This was also the first time that topoisomerase II activity in dinoflagellate cells was detected.
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Affiliation(s)
- Carmen K M Mak
- Biology Department, Hong Kong University of Science and Technology, Clearwater Bay, Kowloon, Hong Kong SAR, People's Republic of China
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Zick A, Onn I, Bezalel R, Margalit H, Shlomai J. Assigning functions to genes: identification of S-phase expressed genes in Leishmania major based on post-transcriptional control elements. Nucleic Acids Res 2005; 33:4235-42. [PMID: 16052032 PMCID: PMC1181863 DOI: 10.1093/nar/gki742] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Assigning functions to genes is one of the major challenges of the post-genomic era. Usually, functions are assigned based on similarity of the coding sequences to sequences of known genes, or by identification of transcriptional cis-regulatory elements that are known to be associated with specific pathways or conditions. In trypanosomatids, where regulation of gene expression takes place mainly at the post-transcriptional level, new approaches for function assignment are needed. Here we demonstrate the identification of novel S-phase expressed genes in Leishmania major, based on a post-transcriptional control element that was recognized in Crithidia fasciculata as involved in the cell cycle-dependent expression of several nuclear and mitochondrial S-phase expressed genes. Hypothesizing that a similar regulatory mechanism is manifested in L.major, we have applied a computational search for similar control elements in the genome of L.major. Our computational scan yielded 132 genes, of which 33% are homologues of known DNA metabolism genes and 63% lack any annotation. Experimental testing of seven of these genes revealed that their mRNAs cycle throughout the cell cycle, reaching a maximum level during S-phase or just prior to it. It is suggested that screening for post-transcriptional control elements associated with a specific function provides an efficient method for assigning functions to trypanosomatid genes.
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Affiliation(s)
- Aviad Zick
- Department of Parasitology, The Kuvin Center for the Study of Infectious and Tropical Diseases, The Hebrew University-Hadassah Medical SchoolJerusalem 91120, Israel
| | - Itay Onn
- Department of Parasitology, The Kuvin Center for the Study of Infectious and Tropical Diseases, The Hebrew University-Hadassah Medical SchoolJerusalem 91120, Israel
- Department of Molecular Genetics and Biotechnology, The Hebrew University-Hadassah Medical SchoolJerusalem 91120, Israel
| | - Rachel Bezalel
- Department of Parasitology, The Kuvin Center for the Study of Infectious and Tropical Diseases, The Hebrew University-Hadassah Medical SchoolJerusalem 91120, Israel
| | - Hanah Margalit
- Department of Molecular Genetics and Biotechnology, The Hebrew University-Hadassah Medical SchoolJerusalem 91120, Israel
| | - Joseph Shlomai
- Department of Parasitology, The Kuvin Center for the Study of Infectious and Tropical Diseases, The Hebrew University-Hadassah Medical SchoolJerusalem 91120, Israel
- To whom correspondence should be addressed. Tel: 972 2 6758089; Fax: 972 2 6757425; E-mail:
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Cavalcanti DP, Fragoso SP, Goldenberg S, de Souza W, Motta MCM. The effect of topoisomerase II inhibitors on the kinetoplast ultrastructure. Parasitol Res 2004; 94:439-48. [PMID: 15517387 DOI: 10.1007/s00436-004-1223-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2004] [Accepted: 08/18/2004] [Indexed: 10/26/2022]
Abstract
Topoisomerases from trypanosomatids play key functions in the replication and organization of kinetoplast DNA (kDNA). Hence, they are considered as potential targets for anti-parasite drugs. In this paper, the effect of topoisomerase II inhibitors, such as nalidixic acid, novobiocin and etoposide, on the ultrastructure of trypanosomatids that present distinct kDNA arrangements was evaluated. Prokaryotic topoisomerase II inhibitors were more effective on growth arrest and ultrastructure changes than etoposide, a eukaryotic topoisomerase II inhibitor. With the exception of novobiocin, drug concentrations which inhibited cell proliferation also promoted kinetoplast ultrastructure alterations, including the redistribution of topoisomerase II. The data reinforce the concept that prokaryotic topoisomerase II inhibitors may offer greater selectivity in drug therapy of trypanosomatid infections.
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Affiliation(s)
- Danielle P Cavalcanti
- Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Bloco G, subsolo, 21949-900, Rio de Janeiro, RJ, Brazil
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Abstract
The protozoan parasites Trypanosoma, Leishmania and Crithidia, which belong to the order kinetoplastidae, emerge from the most ancient eukaryotic lineages. The diversity found in the life cycle of these organisms must be directed by genetic events, wherein topoisomerases play an important role in cellular processes affecting the topology and organization of intracellular DNA. Topoisomerases are valuable as potential drug targets because they have indispensable function in cell biology. This review summarizes what is known about topoisomerase genes and proteins of kinetoplastid parasites and the roles of these enzymes as targets for therapeutic agents.
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Affiliation(s)
- Aditi Das
- Sealy Center for Molecular Sciences, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
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