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Carbajo CG, Han X, Savur B, Upadhyaya A, Taha F, Tinti M, Wheeler RJ, Yates PA, Tiengwe C. A high-throughput protein tagging toolkit that retains endogenous untranslated regions for studying gene regulation in kinetoplastids. Open Biol 2025; 15:240334. [PMID: 39999874 PMCID: PMC11858757 DOI: 10.1098/rsob.240334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2024] [Revised: 01/02/2025] [Accepted: 01/29/2025] [Indexed: 02/27/2025] Open
Abstract
Kinetoplastid parasites cause diseases that threaten human and animal health. To survive transitions between vertebrate hosts and insect vectors, these parasites rely on precise regulation of gene expression to adapt to environmental changes. Since gene regulation in kinetoplastids is primarily post-transcriptional, developing efficient genetic tools for modifying genes at their endogenous loci while preserving regulatory mRNA elements is crucial for studying their complex biology. We present a CRISPR/Cas9-based tagging system that preserves untranslated regulatory elements and uses a viral 2A peptide from Thosea asigna to generate two separate proteins from a single transcript: a drug-selectable marker and a tagged protein of interest. This dual-function design maintains native control elements, allowing discrimination between regulation of transcript abundance, translational efficiency, and post-translational events. We validate the system by tagging six Trypanosoma brucei proteins and demonstrate (i) high-efficiency positive selection and separation of drug-selectable marker and target protein, (ii) preservation of regulatory responses to environmental cues like heat shock and iron availability, and (iii) maintenance of stage-specific regulation during developmental transitions. This versatile toolkit is applicable to all kinetoplastids amenable to CRISPR/Cas9 editing, providing a powerful reverse genetic tool for studying post-transcriptional regulation and protein function in organisms where post-transcriptional control is dominant.
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Affiliation(s)
| | - Xiaoyang Han
- Department of Life Sciences, Imperial College London, London, UK
| | - Bhairavi Savur
- Department of Life Sciences, Imperial College London, London, UK
| | - Arushi Upadhyaya
- Department of Life Sciences, Imperial College London, London, UK
| | - Fatima Taha
- Department of Life Sciences, Imperial College London, London, UK
| | - Michele Tinti
- Wellcome Trust Centre for Anti-Infectives Research, University of Dundee, Dundee, UK
| | - Richard J. Wheeler
- Peter Medawar Building for Pathogen Research, University of Oxford, Oxford, UK
- Institute of Immunology and Infection Research, University of Edinburgh, Edinburgh, UK
| | - Phillip A. Yates
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR, USA
| | - Calvin Tiengwe
- Department of Life Sciences, Imperial College London, London, UK
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2
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Carbajo CG, Han X, Savur B, Upadhyaya A, Taha F, Tinti M, Wheeler RJ, Yates PA, Tiengwe C. A high-throughput protein tagging toolkit that retains endogenous UTRs for studying gene regulation in Kinetoplastids. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2025:2024.11.02.621556. [PMID: 39554005 PMCID: PMC11566017 DOI: 10.1101/2024.11.02.621556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2024]
Abstract
Kinetoplastid parasites cause diseases that threaten human and animal health. To survive transitions between vertebrate hosts and insect vectors, these parasites rely on precise regulation of gene expression to adapt to environmental changes. Since gene regulation in Kinetoplastids is primarily post-transcriptional, developing efficient genetic tools for modifying genes at their endogenous loci while preserving regulatory mRNA elements is crucial for studying their complex biology. We present a CRISPR/Cas9-based tagging system that preserves untranslated regulatory elements and uses a viral 2A peptide from Thosea asigna to generate two separate proteins from a single transcript: a drug-selectable marker and a tagged protein of interest. This dual-function design maintains native control elements, allowing discrimination between regulation of transcript abundance, translational efficiency, and post-translational events. We validate the system by tagging six Trypanosoma brucei proteins and demonstrate: (i) high-efficiency positive selection and separation of drug-selectable marker and target protein, (ii) preservation of regulatory responses to environmental cues like heat shock and iron availability, and (iii) maintenance of stage-specific regulation during developmental transitions. This versatile toolkit is applicable to all kinetoplastids amenable to CRISPR/Cas9 editing, providing a powerful reverse genetic tool for studying post-transcriptional regulation and protein function in organisms where post-transcriptional control is dominant.
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3
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Yanase R, Pruzinova K, Owino BO, Rea E, Moreira-Leite F, Taniguchi A, Nonaka S, Sádlová J, Vojtkova B, Volf P, Sunter JD. Discovery of essential kinetoplastid-insect adhesion proteins and their function in Leishmania-sand fly interactions. Nat Commun 2024; 15:6960. [PMID: 39138209 PMCID: PMC11322530 DOI: 10.1038/s41467-024-51291-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Accepted: 08/01/2024] [Indexed: 08/15/2024] Open
Abstract
Leishmania species, members of the kinetoplastid parasites, cause leishmaniasis, a neglected tropical disease, in millions of people worldwide. Leishmania has a complex life cycle with multiple developmental forms, as it cycles between a sand fly vector and a mammalian host; understanding their life cycle is critical to understanding disease spread. One of the key life cycle stages is the haptomonad form, which attaches to insect tissues through its flagellum. This adhesion, conserved across kinetoplastid parasites, is implicated in having an important function within their life cycles and hence in disease transmission. Here, we discover the kinetoplastid-insect adhesion proteins (KIAPs), which localise in the attached Leishmania flagellum. Deletion of these KIAPs impairs cell adhesion in vitro and prevents Leishmania from colonising the stomodeal valve in the sand fly, without affecting cell growth. Additionally, loss of parasite adhesion in the sand fly results in reduced physiological changes to the fly, with no observable damage of the stomodeal valve and reduced midgut swelling. These results provide important insights into a comprehensive understanding of the Leishmania life cycle, which will be critical for developing transmission-blocking strategies.
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Affiliation(s)
- Ryuji Yanase
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, UK.
- School of Life Sciences, University of Nottingham, Nottingham, UK.
- Department of Genetics and Genome Biology, University of Leicester, Leicester, UK.
| | - Katerina Pruzinova
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czechia
| | - Barrack O Owino
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, UK
| | - Edward Rea
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, UK
| | - Flávia Moreira-Leite
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, UK
- Department of Biochemistry, Central Oxford Structural Molecular Imaging Centre (COSMIC), University of Oxford, Oxford, UK
| | - Atsushi Taniguchi
- Laboratory for Spatiotemporal Regulations, National Institute for Basic Biology, Okazaki, Japan
- Research Center of Mathematics for Social Creativity, Research Institute for Electronic Science, Hokkaido University, Sapporo, Japan
| | - Shigenori Nonaka
- Laboratory for Spatiotemporal Regulations, National Institute for Basic Biology, Okazaki, Japan
- Spatiotemporal Regulations Group, Exploratory Research Center for Life and Living Systems, Okazaki, Japan
- Department of Basic Biology, School of Life Science, SOKENDAI, Okazaki, Japan
| | - Jovana Sádlová
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czechia
| | - Barbora Vojtkova
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czechia
| | - Petr Volf
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czechia.
| | - Jack D Sunter
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, UK.
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4
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Jentzsch J, Wunderlich H, Thein M, Bechthold J, Brehm L, Krauss SW, Weiss M, Ersfeld K. Microtubule polyglutamylation is an essential regulator of cytoskeletal integrity in Trypanosoma brucei. J Cell Sci 2024; 137:jcs261740. [PMID: 38205672 DOI: 10.1242/jcs.261740] [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: 10/19/2023] [Accepted: 01/02/2024] [Indexed: 01/12/2024] Open
Abstract
Tubulin polyglutamylation, catalysed by members of the tubulin tyrosine ligase-like (TTLL) protein family, is an evolutionarily highly conserved mechanism involved in the regulation of microtubule dynamics and function in eukaryotes. In the protozoan parasite Trypanosoma brucei, the microtubule cytoskeleton is essential for cell motility and maintaining cell shape. In a previous study, we showed that T. brucei TTLL6A and TTLL12B are required to regulate microtubule dynamics at the posterior cell pole. Here, using gene deletion, we show that the polyglutamylase TTLL1 is essential for the integrity of the highly organised microtubule structure at the cell pole, with a phenotype distinct from that observed in TTLL6A- and TTLL12B-depleted cells. Reduced polyglutamylation in TTLL1-deficient cells also leads to increased levels in tubulin tyrosination, providing new evidence for an interplay between the tubulin tyrosination and detyrosination cycle and polyglutamylation. We also show that TTLL1 acts differentially on specific microtubule doublets of the flagellar axoneme, although the absence of TTLL1 appears to have no measurable effect on cell motility.
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Affiliation(s)
- Jana Jentzsch
- Molecular Parasitology, Department of Biology, University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany
| | - Hannes Wunderlich
- Experimental Physics I, Department of Physics, University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany
| | - Marinus Thein
- Molecular Parasitology, Department of Biology, University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany
| | - Julia Bechthold
- Molecular Parasitology, Department of Biology, University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany
| | - Lucas Brehm
- Molecular Parasitology, Department of Biology, University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany
| | - Sebastian W Krauss
- Experimental Physics I, Department of Physics, University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany
| | - Matthias Weiss
- Experimental Physics I, Department of Physics, University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany
| | - Klaus Ersfeld
- Molecular Parasitology, Department of Biology, University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany
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Jamabo M, Mahlalela M, Edkins AL, Boshoff A. Tackling Sleeping Sickness: Current and Promising Therapeutics and Treatment Strategies. Int J Mol Sci 2023; 24:12529. [PMID: 37569903 PMCID: PMC10420020 DOI: 10.3390/ijms241512529] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 07/27/2023] [Accepted: 08/03/2023] [Indexed: 08/13/2023] Open
Abstract
Human African trypanosomiasis is a neglected tropical disease caused by the extracellular protozoan parasite Trypanosoma brucei, and targeted for eradication by 2030. The COVID-19 pandemic contributed to the lengthening of the proposed time frame for eliminating human African trypanosomiasis as control programs were interrupted. Armed with extensive antigenic variation and the depletion of the B cell population during an infectious cycle, attempts to develop a vaccine have remained unachievable. With the absence of a vaccine, control of the disease has relied heavily on intensive screening measures and the use of drugs. The chemotherapeutics previously available for disease management were plagued by issues such as toxicity, resistance, and difficulty in administration. The approval of the latest and first oral drug, fexinidazole, is a major chemotherapeutic achievement for the treatment of human African trypanosomiasis in the past few decades. Timely and accurate diagnosis is essential for effective treatment, while poor compliance and resistance remain outstanding challenges. Drug discovery is on-going, and herein we review the recent advances in anti-trypanosomal drug discovery, including novel potential drug targets. The numerous challenges associated with disease eradication will also be addressed.
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Affiliation(s)
- Miebaka Jamabo
- Biotechnology Innovation Centre, Rhodes University, Makhanda 6139, South Africa; (M.J.); (M.M.)
| | - Maduma Mahlalela
- Biotechnology Innovation Centre, Rhodes University, Makhanda 6139, South Africa; (M.J.); (M.M.)
| | - Adrienne L. Edkins
- Department of Biochemistry and Microbiology, Biomedical Biotechnology Research Centre (BioBRU), Rhodes University, Makhanda 6139, South Africa;
| | - Aileen Boshoff
- Biotechnology Innovation Centre, Rhodes University, Makhanda 6139, South Africa; (M.J.); (M.M.)
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Genome-wide subcellular protein map for the flagellate parasite Trypanosoma brucei. Nat Microbiol 2023; 8:533-547. [PMID: 36804636 PMCID: PMC9981465 DOI: 10.1038/s41564-022-01295-6] [Citation(s) in RCA: 77] [Impact Index Per Article: 38.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 11/21/2022] [Indexed: 02/22/2023]
Abstract
Trypanosoma brucei is a model trypanosomatid, an important group of human, animal and plant unicellular parasites. Understanding their complex cell architecture and life cycle is challenging because, as with most eukaryotic microbes, ~50% of genome-encoded proteins have completely unknown functions. Here, using fluorescence microscopy and cell lines expressing endogenously tagged proteins, we mapped the subcellular localization of 89% of the T. brucei proteome, a resource we call TrypTag. We provide clues to function and define lineage-specific organelle adaptations for parasitism, mapping the ultraconserved cellular architecture of eukaryotes, including the first comprehensive 'cartographic' analysis of the eukaryotic flagellum, which is vital for morphogenesis and pathology. To demonstrate the power of this resource, we identify novel organelle subdomains and changes in molecular composition through the cell cycle. TrypTag is a transformative resource, important for hypothesis generation for both eukaryotic evolutionary molecular cell biology and fundamental parasite cell biology.
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Oliveira ACS, Rezende L, Gorshkov V, Melo-Braga MN, Verano-Braga T, Fernandes-Braga W, Guadalupe JLDM, de Menezes GB, Kjeldsen F, de Andrade HM, Andrade LDO. Biological and Molecular Effects of Trypanosoma cruzi Residence in a LAMP-Deficient Intracellular Environment. Front Cell Infect Microbiol 2022; 11:788482. [PMID: 35071040 PMCID: PMC8770540 DOI: 10.3389/fcimb.2021.788482] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Accepted: 12/06/2021] [Indexed: 01/08/2023] Open
Abstract
Trypanosoma cruzi invades non-professional phagocytic cells by subverting their membrane repair process, which is dependent on membrane injury and cell signaling, intracellular calcium increase, and lysosome recruitment. Cells lacking lysosome-associated membrane proteins 1 and 2 (LAMP1 and LAMP2) are less permissive to parasite invasion but more prone to parasite intracellular multiplication. Several passages through a different intracellular environment can significantly change T. cruzi's gene expression profile. Here, we evaluated whether one single passage through LAMP-deficient (KO) or wild-type (WT) fibroblasts, thus different intracellular environments, could influence T. cruzi Y strain trypomastigotes' ability to invade L6 myoblasts and WT fibroblasts host cells. Parasites released from LAMP2 KO cells (TcY-L2-/-) showed higher invasion, calcium signaling, and membrane injury rates, for the assays in L6 myoblasts, when compared to those released from WT (TcY-WT) or LAMP1/2 KO cells (TcY-L1/2-/-). On the other hand, TcY-L1/2-/- showed higher invasion, calcium signaling, and cell membrane injury rates, for the assays in WT fibroblasts, compared to TcY-WT and TcY-L1/2-/-. Albeit TcY-WT presented an intermediary invasion and calcium signaling rates, compared to the others, in WT fibroblasts, they induced lower levels of injury, which reinforces that signals mediated by surface membrane protein interactions also have a significant contribution to trigger host cell calcium signals. These results clearly show that parasites released from WT or LAMP KO cells are distinct from each other. Additionally, these parasites' ability to invade the cell may be distinct depending on which cell type they interact with. Since these alterations most likely would reflect differences among parasite surface molecules, we also evaluated their proteome. We identified few protein complexes, membrane, and secreted proteins regulated in our dataset. Among those are some members of MASP, mucins, trans-sialidases, and gp63 proteins family, which are known to play an important role during parasite infection and could correlate to TcY-WT, TcY-L1/2-/-, and TcY-L2-/- biological behavior.
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Affiliation(s)
- Anny Carolline Silva Oliveira
- Department of Morphology, Biological Sciences Institute—ICB, Federal University of Minas Gerais (UFMG), Belo Horizonte, Brazil
- Protein Research Group, Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Luisa Rezende
- Department of Morphology, Biological Sciences Institute—ICB, Federal University of Minas Gerais (UFMG), Belo Horizonte, Brazil
| | - Vladimir Gorshkov
- Protein Research Group, Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Marcella Nunes Melo-Braga
- Department of Biochemistry and Immunology, Biological Sciences Institute—ICB, Federal University of Minas Gerais (UFMG), Belo Horizonte, Minas Gerais, Brazil
| | - Thiago Verano-Braga
- Hypertension Lab/Functional Proteomics Group, Department of Physiology and Biophysics, Biological Sciences Institute—ICB, Federal University of Minas Gerais (UFMG), Belo Horizonte, Brazil
| | - Weslley Fernandes-Braga
- Department of Biochemistry and Immunology, Biological Sciences Institute—ICB, Federal University of Minas Gerais (UFMG), Belo Horizonte, Minas Gerais, Brazil
| | - Jorge Luís de Melo Guadalupe
- Department of Morphology, Biological Sciences Institute—ICB, Federal University of Minas Gerais (UFMG), Belo Horizonte, Brazil
| | - Gustavo Batista de Menezes
- Department of Morphology, Biological Sciences Institute—ICB, Federal University of Minas Gerais (UFMG), Belo Horizonte, Brazil
| | - Frank Kjeldsen
- Protein Research Group, Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Hélida Monteiro de Andrade
- Laboratory of Leishmanioses, Department of Parasitology, Biological Sciences Institute—ICB, Federal University of Minas Gerais (UFMG), Belo Horizonte, Brazil
| | - Luciana de Oliveira Andrade
- Department of Morphology, Biological Sciences Institute—ICB, Federal University of Minas Gerais (UFMG), Belo Horizonte, Brazil
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Novel Cytoskeleton-Associated Proteins in Trypanosoma brucei Are Essential for Cell Morphogenesis and Cytokinesis. Microorganisms 2021; 9:microorganisms9112234. [PMID: 34835360 PMCID: PMC8625193 DOI: 10.3390/microorganisms9112234] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 10/19/2021] [Accepted: 10/22/2021] [Indexed: 11/24/2022] Open
Abstract
Trypanosome brucei, the causative agent of African sleeping sickness, harbours a highly ordered, subpellicular microtubule cytoskeleton that defines many aspects of morphology, motility and virulence. This array of microtubules is associated with a large number of proteins involved in its regulation. Employing proximity-dependent biotinylation assay (BioID) using the well characterised cytoskeleton-associated protein CAP5.5 as a probe, we identified CAP50 (Tb927.11.2610). This protein colocalises with the subpellicular cytoskeleton microtubules but not with the flagellum. Depletion by RNAi results in defects in cytokinesis, morphology and partial disorganisation of microtubule arrays. Published proteomics data indicate a possible association of CAP50 with two other, yet uncharacterised, cytoskeletal proteins, CAP52 (Tb927.6.5070) and CAP42 (Tb927.4.1300), which were therefore included in our analysis. We show that their depletion causes phenotypes similar to those described for CAP50 and that they are essential for cellular integrity.
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Dean S. Basic Biology of Trypanosoma brucei with Reference to the Development of Chemotherapies. Curr Pharm Des 2021; 27:1650-1670. [PMID: 33463458 DOI: 10.2174/1381612827666210119105008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 12/01/2020] [Accepted: 12/08/2020] [Indexed: 11/22/2022]
Abstract
Trypanosoma brucei are protozoan parasites that cause the lethal human disease African sleeping sickness and the economically devastating disease of cattle, Nagana. African sleeping sickness, also known as Human African Trypanosomiasis (HAT), threatens 65 million people and animal trypanosomiasis makes large areas of farmland unusable. There is no vaccine and licensed therapies against the most severe, late-stage disease are toxic, impractical and ineffective. Trypanosomes are transmitted by tsetse flies, and HAT is therefore predominantly confined to the tsetse fly belt in sub-Saharan Africa. They are exclusively extracellular and they differentiate between at least seven developmental forms that are highly adapted to host and vector niches. In the mammalian (human) host they inhabit the blood, cerebrospinal fluid (late-stage disease), skin, and adipose fat. In the tsetse fly vector they travel from the tsetse midgut to the salivary glands via the ectoperitrophic space and proventriculus. Trypanosomes are evolutionarily divergent compared with most branches of eukaryotic life. Perhaps most famous for their extraordinary mechanisms of monoallelic gene expression and antigenic variation, they have also been investigated because much of their biology is either highly unconventional or extreme. Moreover, in addition to their importance as pathogens, many researchers have been attracted to the field because trypanosomes have some of the most advanced molecular genetic tools and database resources of any model system. The following will cover just some aspects of trypanosome biology and how its divergent biochemistry has been leveraged to develop drugs to treat African sleeping sickness. This is by no means intended to be a comprehensive survey of trypanosome features. Rather, I hope to present trypanosomes as one of the most fascinating and tractable systems to do discovery biology.
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Affiliation(s)
- Samuel Dean
- Warwick Medical School, University of Warwick, Coventry, CV4 7AL, United Kingdom
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Ennes-Vidal V, Branquinha MH, dos Santos ALS, d’Avila-Levy CM. The Diverse Calpain Family in Trypanosomatidae: Functional Proteins Devoid of Proteolytic Activity? Cells 2021; 10:cells10020299. [PMID: 33535641 PMCID: PMC7912814 DOI: 10.3390/cells10020299] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 01/19/2021] [Accepted: 01/20/2021] [Indexed: 11/25/2022] Open
Abstract
Calpains are calcium-dependent cysteine peptidases that were originally described in mammals and, thereafter, their homologues were identified in almost all known living organisms. The deregulated activity of these peptidases is associated with several pathologies and, consequently, huge efforts have been made to identify selective inhibitors. Trypanosomatids, responsible for life-threatening human diseases, possess a large and diverse family of calpain sequences in their genomes. Considering that the current therapy to treat trypanosomatid diseases is limited to a handful of drugs that suffer from unacceptable toxicity, tough administration routes, like parenteral, and increasing treatment failures, a repurposed approach with calpain inhibitors could be a shortcut to successful chemotherapy. However, there is a general lack of knowledge about calpain functions in these parasites and, currently, the proteolytic activity of these proteins is still an open question. Here, we highlight the current research and perspectives on trypanosomatid calpains, overview calpain description in these organisms, and explore the potential of targeting the calpain system as a therapeutic strategy. This review gathers the current knowledge about this fascinating family of peptidases as well as insights into the puzzle: are we unable to measure calpain activity in trypanosomatids, or are the functions of these proteins devoid of proteolytic activity in these parasites?
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Affiliation(s)
- Vítor Ennes-Vidal
- Laboratório de Estudos Integrados em Protozoologia, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz (FIOCRUZ), 21040-360 Rio de Janeiro, Brazil;
- Correspondence: ; Tel.: +55-21-2562-1014
| | - Marta Helena Branquinha
- Laboratório de Estudos Avançados de Microrganismos Emergentes e Resistentes, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro (UFRJ), 21941-901 Rio de Janeiro, Brazil; (M.H.B.); (A.L.S.d.S.)
| | - André Luis Souza dos Santos
- Laboratório de Estudos Avançados de Microrganismos Emergentes e Resistentes, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro (UFRJ), 21941-901 Rio de Janeiro, Brazil; (M.H.B.); (A.L.S.d.S.)
- Programa de Pós-Graduação em Bioquímica, Instituto de Química, Universidade Federal do Rio de Janeiro (UFRJ), 21941-909 Rio de Janeiro, Brazil
| | - Claudia Masini d’Avila-Levy
- Laboratório de Estudos Integrados em Protozoologia, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz (FIOCRUZ), 21040-360 Rio de Janeiro, Brazil;
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Ennes-Vidal V, Pitaluga AN, Britto CFDPDC, Branquinha MH, Santos ALSD, Menna-Barreto RFS, d'Avila-Levy CM. Expression and cellular localisation of Trypanosoma cruzi calpains. Mem Inst Oswaldo Cruz 2020; 115:e200142. [PMID: 33053076 PMCID: PMC7552305 DOI: 10.1590/0074-02760200142] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 09/09/2020] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Calpains are present in almost all organisms and comprise a family of calcium-dependent cysteine peptidases implicated in crucial cellular functions. Trypanosoma cruzi, the causative agent of Chagas disease, presents an expansion on this gene family with unexplored biological properties. OBJECTIVES Here, we searched for calpains in the T. cruzi genome, evaluated the mRNA levels, calpain activity and the protein expression and determined the cellular localisation in all three parasite life cycle forms. METHODS/FINDINGS Sixty-three calpain sequences were identified in T. cruzi CL Brener genome, with fourteen domain arrangements. The comparison of calpain mRNA abundance by quantitative polymerase chain reaction (qPCR) revealed seven up-regulated sequences in amastigotes and/or bloodstream trypomastigotes and five in epimastigotes. Western Blotting analysis revealed seven different molecules in the three parasite forms, and one amastigote-specific, while no proteolytic activity could be detected. Flow cytometry assays revealed a higher amount of intracellular calpains in amastigotes and/or trypomastigotes in comparison to epimastigotes. Finally, ultrastructural analysis revealed the presence of calpains in the cytoplasm, vesicular and plasma membranes of the three parasite forms, and in the paraflagellar rod in trypomastigotes. CONCLUSION Calpains are differentially expressed and localised in the T. cruzi life cycle forms. This study adds data on the calpain occurrence and expression pattern in T. cruzi.
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Affiliation(s)
- Vítor Ennes-Vidal
- Fundação Oswaldo Cruz-Fiocruz, Instituto Oswaldo Cruz, Laboratório de Estudos Integrados em Protozoologia, Rio de Janeiro, RJ, Brasil
| | - André Nóbrega Pitaluga
- Fundação Oswaldo Cruz-Fiocruz, Instituto Oswaldo Cruz, Laboratório de Biologia Molecular de Parasitas e Vetores, Rio de Janeiro, RJ, Brasil
| | | | - Marta Helena Branquinha
- Universidade Federal do Rio de Janeiro, Instituto de Microbiologia Paulo de Góes, Laboratório de Estudos Avançados de Microrganismos Emergentes e Resistentes, Rio de Janeiro, RJ, Brasil
| | - André Luis Souza Dos Santos
- Universidade Federal do Rio de Janeiro, Instituto de Microbiologia Paulo de Góes, Laboratório de Estudos Avançados de Microrganismos Emergentes e Resistentes, Rio de Janeiro, RJ, Brasil.,Universidade Federal do Rio de Janeiro, Instituto de Química, Programa de Pós-Graduação em Bioquímica, Rio de Janeiro, RJ, Brasil
| | | | - Claudia Masini d'Avila-Levy
- Fundação Oswaldo Cruz-Fiocruz, Instituto Oswaldo Cruz, Laboratório de Estudos Integrados em Protozoologia, Rio de Janeiro, RJ, Brasil
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Jentzsch J, Sabri A, Speckner K, Lallinger-Kube G, Weiss M, Ersfeld K. Microtubule polyglutamylation is important for regulating cytoskeletal architecture and motility in Trypanosoma brucei. J Cell Sci 2020; 133:jcs248047. [PMID: 32843576 DOI: 10.1242/jcs.248047] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 07/30/2020] [Indexed: 11/20/2022] Open
Abstract
The shape of kinetoplastids, such as Trypanosoma brucei, is precisely defined during the stages of the life cycle and governed by a stable subpellicular microtubule cytoskeleton. During the cell cycle and transitions between life cycle stages, this stability has to transiently give way to a dynamic behaviour to enable cell division and morphological rearrangements. How these opposing requirements of the cytoskeleton are regulated is poorly understood. Two possible levels of regulation are activities of cytoskeleton-associated proteins and microtubule post-translational modifications (PTMs). Here, we investigate the functions of two putative tubulin polyglutamylases in T. brucei, TTLL6A and TTLL12B. Depletion of both proteins leads to a reduction in tubulin polyglutamylation in situ and is associated with disintegration of the posterior cell pole, loss of the microtubule plus-end-binding protein EB1 and alterations of microtubule dynamics. We also observe a reduced polyglutamylation of the flagellar axoneme. Quantitative motility analysis reveals that the PTM imbalance correlates with a transition from directional to diffusive cell movement. These data show that microtubule polyglutamylation has an important role in regulating cytoskeletal architecture and motility in the parasite T. bruceiThis article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Jana Jentzsch
- Molecular Parasitology, Department of Biology, University of Bayreuth, Universitätsstr. 30, 95447 Bayreuth, Germany
| | - Adal Sabri
- Experimental Physics I, Department of Physics, University of Bayreuth, Universitätsstr. 30, 95447 Bayreuth, Germany
| | - Konstantin Speckner
- Experimental Physics I, Department of Physics, University of Bayreuth, Universitätsstr. 30, 95447 Bayreuth, Germany
| | - Gertrud Lallinger-Kube
- Molecular Parasitology, Department of Biology, University of Bayreuth, Universitätsstr. 30, 95447 Bayreuth, Germany
| | - Matthias Weiss
- Experimental Physics I, Department of Physics, University of Bayreuth, Universitätsstr. 30, 95447 Bayreuth, Germany
| | - Klaus Ersfeld
- Molecular Parasitology, Department of Biology, University of Bayreuth, Universitätsstr. 30, 95447 Bayreuth, Germany
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13
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Chaimon S, Limpanont Y, Reamtong O, Ampawong S, Phuphisut O, Chusongsang P, Ruangsittichai J, Boonyuen U, Watthanakulpanich D, O'Donoghue AJ, Caffrey CR, Adisakwattana P. Molecular characterization and functional analysis of the Schistosoma mekongi Ca 2+-dependent cysteine protease (calpain). Parasit Vectors 2019; 12:383. [PMID: 31362766 PMCID: PMC6668146 DOI: 10.1186/s13071-019-3639-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Accepted: 07/25/2019] [Indexed: 11/22/2022] Open
Abstract
Background Schistosoma mekongi, which causes schistosomiasis in humans, is an important public health issue in Southeast Asia. Treatment with praziquantel is the primary method of control but emergence of praziquantel resistance requires the development of alternative drugs and vaccines. Calcium-dependent cysteine protease (calpain) is a novel vaccine candidate that has been studied in S. mansoni, S. japonicum, and protozoans including malaria, leishmania and trypanosomes. However, limited information is available on the properties and functions of calpain in other Schistosoma spp., including S. mekongi. In this study, we functionally characterized calpain 1 of S. mekongi (SmeCalp1). Results Calpain 1 of S. mekongi was obtained from transcriptomic analysis of S. mekongi; it had the highest expression level of all isoforms tested and was predominantly expressed in the adult male. SmeCalp1 cDNA is 2274 bp long and encodes 758 amino acids, with 85% to 90% homology with calpains in other Schistosoma species. Recombinant SmeCalp1 (rSmeCalp1), with a molecular weight of approximately 86.7 kDa, was expressed in bacteria and stimulated a marked antibody response in mice. Native SmeCalp1 was detected in crude worm extract and excretory-secretory product, and it was mainly localized in the tegument of the adult male; less signal was detected in the adult female worm. Thus, SmeCalp1 may play a role in surface membrane synthesis or host–parasite interaction. We assessed the protease activity of rSmeCalp1 and demonstrated that rSmeCalp1 could cleave the calpain substrate N-succinyl-Leu-Leu-Val-Tyr-7-amino-4-methylcoumarin, that was inhibited by calpain inhibitors (MDL28170 and E64c). Additionally, rSmeCalp1 could degrade the biological substrates fibronectin (blood clotting protein) and human complement C3, indicating important roles in the intravascular system and in host immune evasion. Conclusions SmeCalp1 is expressed on the tegumental surface of the parasite and can cleave host defense molecules; thus, it might participate in growth, development and survival during the entire life-cycle of S. mekongi. Information on the properties and functions of SmeCalp1 reported herein will be advantageous in the development of effective drugs and vaccines against S. mekongi and other schistosomes. Electronic supplementary material The online version of this article (10.1186/s13071-019-3639-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Salisa Chaimon
- Department of Helminthology, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Yanin Limpanont
- Department of Social and Environmental Medicine, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Onrapak Reamtong
- Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Sumate Ampawong
- Department of Tropical Pathology, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Orawan Phuphisut
- Department of Helminthology, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Phiraphol Chusongsang
- Department of Social and Environmental Medicine, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Jiraporn Ruangsittichai
- Department of Medical Entomology, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Usa Boonyuen
- Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Dorn Watthanakulpanich
- Department of Helminthology, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Anthony J O'Donoghue
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, San Diego, California, USA
| | - Conor R Caffrey
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, San Diego, California, USA
| | - Poom Adisakwattana
- Department of Helminthology, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand.
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14
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Trypanosoma cruzi immunoproteome: Calpain-like CAP5.5 differentially detected throughout distinct stages of human Chagas disease cardiomyopathy. J Proteomics 2019; 194:179-190. [DOI: 10.1016/j.jprot.2018.11.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 10/22/2018] [Accepted: 11/28/2018] [Indexed: 12/26/2022]
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15
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Domínguez-Fernández T, Rodríguez MA, Sánchez Monroy V, Gómez García C, Medel O, Pérez Ishiwara DG. A Calpain-Like Protein Is Involved in the Execution Phase of Programmed Cell Death of Entamoeba histolytica. Front Cell Infect Microbiol 2018; 8:339. [PMID: 30319995 PMCID: PMC6167430 DOI: 10.3389/fcimb.2018.00339] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Accepted: 09/06/2018] [Indexed: 01/27/2023] Open
Abstract
Oxygen or nitrogen oxidative species and chemical stress induce the programmed cell death (PCD) of Entamoeba histolytica trophozoites. PCD caused by the aminoglycoside G418 is reduced by incubation with the cysteine protease inhibitor E-64; however, no typical caspases or metacaspases have been detected in this parasite. Calpain, a cysteine protease activated by calcium, has been suggested to be part of a specific PCD pathway in this parasite because the specific calpain inhibitor Z-Leu-Leu-Leu-al diminishes the PCD of trophozoites. Here, we predicted the hypothetical 3D structure of a calpain-like protein of E. histolytica and produced specific antibodies against it. We detected the protein in the cytoplasm and near the nucleus. Its expression gradually increased during incubation with G418, with the highest level after 9 h of treatment. In addition, a specific calpain-like siRNA sequence reduced the cell death rate by 65%. All these results support the hypothesis that the calpain-like protein is one of the proteases involved in the execution phase of PCD in E. histolytica. The hypothetical interactome of the calpain-like protein suggests that it may activate or regulate other proteins that probably participate in PCD, including those with EF-hand domains or other calcium-binding sites.
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Affiliation(s)
| | | | - Virginia Sánchez Monroy
- Programa de Biomedicina Molecular, Escuela Nacional de Medicina y Homeopatía (ENMyH), Instituto Politécnico Nacional, Ciudad de México, Mexico
| | - Consuelo Gómez García
- Programa de Biomedicina Molecular, Escuela Nacional de Medicina y Homeopatía (ENMyH), Instituto Politécnico Nacional, Ciudad de México, Mexico
| | - Olivia Medel
- Programa de Biomedicina Molecular, Escuela Nacional de Medicina y Homeopatía (ENMyH), Instituto Politécnico Nacional, Ciudad de México, Mexico
| | - David Guillermo Pérez Ishiwara
- Programa de Biomedicina Molecular, Escuela Nacional de Medicina y Homeopatía (ENMyH), Instituto Politécnico Nacional, Ciudad de México, Mexico
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16
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Hilton NA, Sladewski TE, Perry JA, Pataki Z, Sinclair-Davis AN, Muniz RS, Tran HL, Wurster JI, Seo J, de Graffenried CL. Identification of TOEFAZ1-interacting proteins reveals key regulators of Trypanosoma brucei cytokinesis. Mol Microbiol 2018; 109:306-326. [PMID: 29781112 PMCID: PMC6359937 DOI: 10.1111/mmi.13986] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/13/2018] [Indexed: 01/07/2023]
Abstract
The protist parasite Trypanosoma brucei is an obligate extracellular pathogen that retains its highly polarized morphology during cell division and has evolved a novel cytokinetic process independent of non-muscle myosin II. The polo-like kinase homolog TbPLK is essential for transmission of cell polarity during division and for cytokinesis. We previously identified a putative TbPLK substrate named Tip of the Extending FAZ 1 (TOEFAZ1) as an essential kinetoplastid-specific component of the T. brucei cytokinetic machinery. We performed a proximity-dependent biotinylation identification (BioID) screen using TOEFAZ1 as a means to identify additional proteins that are involved in cytokinesis. Using quantitative proteomic methods, we identified nearly 500 TOEFAZ1-proximal proteins and characterized 59 in further detail. Among the candidates, we identified an essential putative phosphatase that regulates the expression level and localization of both TOEFAZ1 and TbPLK, a previously uncharacterized protein that is necessary for the assembly of a new cell posterior, and a microtubule plus-end directed orphan kinesin that is required for completing cleavage furrow ingression. The identification of these proteins provides new insight into T. brucei cytokinesis and establishes TOEFAZ1 as a key component of this essential and uniquely configured process in kinetoplastids.
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Affiliation(s)
- Nicholas A. Hilton
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI, 02912
| | - Thomas E. Sladewski
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI, 02912
| | - Jenna A. Perry
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI, 02912
| | - Zemplen Pataki
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI, 02912
| | - Amy N. Sinclair-Davis
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI, 02912
| | - Richard S. Muniz
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI, 02912
| | - Holly L. Tran
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI, 02912
| | - Jenna I. Wurster
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI, 02912
| | - Jiwon Seo
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI, 02912
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17
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Adenylate Cyclases of Trypanosoma brucei, Environmental Sensors and Controllers of Host Innate Immune Response. Pathogens 2018; 7:pathogens7020048. [PMID: 29693583 PMCID: PMC6027212 DOI: 10.3390/pathogens7020048] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 04/12/2018] [Accepted: 04/20/2018] [Indexed: 12/12/2022] Open
Abstract
Trypanosoma brucei, etiological agent of Sleeping Sickness in Africa, is the prototype of African trypanosomes, protozoan extracellular flagellate parasites transmitted by saliva (Salivaria). In these parasites the molecular controls of the cell cycle and environmental sensing are elaborate and concentrated at the flagellum. Genomic analyses suggest that these parasites appear to differ considerably from the host in signaling mechanisms, with the exception of receptor-type adenylate cyclases (AC) that are topologically similar to receptor-type guanylate cyclase (GC) of higher eukaryotes but control a new class of cAMP targets of unknown function, the cAMP response proteins (CARPs), rather than the classical protein kinase A cAMP effector (PKA). T. brucei possesses a large polymorphic family of ACs, mainly associated with the flagellar membrane, and these are involved in inhibition of the innate immune response of the host prior to the massive release of immunomodulatory factors at the first peak of parasitemia. Recent evidence suggests that in T. brucei several insect-specific AC isoforms are involved in social motility, whereas only a few AC isoforms are involved in cytokinesis control of bloodstream forms, attesting that a complex signaling pathway is required for environmental sensing. In this review, after a general update on cAMP signaling pathway and the multiple roles of cAMP, I summarize the existing knowledge of the mechanisms by which pathogenic microorganisms modulate cAMP levels to escape immune defense.
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18
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Tiwary P, Kumar D, Sundar S. Identification and Functional Validation of a Biomarker for the Diagnosis of Miltefosine Relapse during Visceral Leishmaniasis. Am J Trop Med Hyg 2017; 98:492-496. [PMID: 29280431 DOI: 10.4269/ajtmh.16-0983] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Miltefosine is the only orally administrable drug for the treatment of leishmaniasis. But in recent years, a decline in its efficacy points toward the emergence of resistance to this drug. Knowledge of biomarkers for miltefosine resistance may be beneficial for proper selection of treatment regimen. Splenic aspirates were collected and parasites cultured from patients relapsed after initial cure (N = 15) and successfully treated (N = 15) with miltefosine. Differential expression of genes in miltefosine-resistant strains was examined by DNA microarray and validated by real-time reverse transcription polymerase chain reaction and Western blotting. Of 669 upregulated genes, the cysteine protease-like protein of calpain family (GenBank: CBZ34784) was found to be significantly overexpressed in resistant parasite strains and only anti-calpain antibodies showed its presence in the sera of relapse patients through Western blotting. Calpain family cysteine protease-like protein can be useful as a potential biomarker of miltefosine unresponsiveness.
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Affiliation(s)
- Puja Tiwary
- Department of Medicine, Infectious Disease Research Laboratory, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India
| | - Dinesh Kumar
- Department of Medicine, Infectious Disease Research Laboratory, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India
| | - Shyam Sundar
- Department of Medicine, Infectious Disease Research Laboratory, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India
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19
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Bayliss T, Robinson DA, Smith VC, Brand S, McElroy SP, Torrie LS, Mpamhanga C, Norval S, Stojanovski L, Brenk R, Frearson JA, Read KD, Gilbert IH, Wyatt PG. Design and Synthesis of Brain Penetrant Trypanocidal N-Myristoyltransferase Inhibitors. J Med Chem 2017; 60:9790-9806. [PMID: 29125744 PMCID: PMC5734605 DOI: 10.1021/acs.jmedchem.7b01255] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
N-Myristoyltransferase (NMT) represents a promising drug target within the parasitic protozoa Trypanosoma brucei (T. brucei), the causative agent for human African trypanosomiasis (HAT) or sleeping sickness. We have previously validated T. brucei NMT as a promising druggable target for the treatment of HAT in both stages 1 and 2 of the disease. We report on the use of the previously reported DDD85646 (1) as a starting point for the design of a class of potent, brain penetrant inhibitors of T. brucei NMT.
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Affiliation(s)
- Tracy Bayliss
- Drug Discovery Unit, College of Life Sciences, University of Dundee , Sir James Black Centre, Dundee DD1 5EH, U.K
| | - David A Robinson
- Drug Discovery Unit, College of Life Sciences, University of Dundee , Sir James Black Centre, Dundee DD1 5EH, U.K
| | - Victoria C Smith
- Drug Discovery Unit, College of Life Sciences, University of Dundee , Sir James Black Centre, Dundee DD1 5EH, U.K
| | - Stephen Brand
- Drug Discovery Unit, College of Life Sciences, University of Dundee , Sir James Black Centre, Dundee DD1 5EH, U.K
| | - Stuart P McElroy
- Drug Discovery Unit, College of Life Sciences, University of Dundee , Sir James Black Centre, Dundee DD1 5EH, U.K
| | - Leah S Torrie
- Drug Discovery Unit, College of Life Sciences, University of Dundee , Sir James Black Centre, Dundee DD1 5EH, U.K
| | - Chido Mpamhanga
- Drug Discovery Unit, College of Life Sciences, University of Dundee , Sir James Black Centre, Dundee DD1 5EH, U.K
| | - Suzanne Norval
- Drug Discovery Unit, College of Life Sciences, University of Dundee , Sir James Black Centre, Dundee DD1 5EH, U.K
| | - Laste Stojanovski
- Drug Discovery Unit, College of Life Sciences, University of Dundee , Sir James Black Centre, Dundee DD1 5EH, U.K
| | - Ruth Brenk
- Drug Discovery Unit, College of Life Sciences, University of Dundee , Sir James Black Centre, Dundee DD1 5EH, U.K
| | - Julie A Frearson
- Drug Discovery Unit, College of Life Sciences, University of Dundee , Sir James Black Centre, Dundee DD1 5EH, U.K
| | - Kevin D Read
- Drug Discovery Unit, College of Life Sciences, University of Dundee , Sir James Black Centre, Dundee DD1 5EH, U.K
| | - Ian H Gilbert
- Drug Discovery Unit, College of Life Sciences, University of Dundee , Sir James Black Centre, Dundee DD1 5EH, U.K
| | - Paul G Wyatt
- Drug Discovery Unit, College of Life Sciences, University of Dundee , Sir James Black Centre, Dundee DD1 5EH, U.K
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20
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In vitro selection of Phytomonas serpens cells resistant to the calpain inhibitor MDL28170: alterations in fitness and expression of the major peptidases and efflux pumps. Parasitology 2017; 145:355-370. [PMID: 29039273 DOI: 10.1017/s0031182017001561] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The species Phytomonas serpens is known to express some molecules displaying similarity to those described in trypanosomatids pathogenic to humans, such as peptidases from Trypanosoma cruzi (cruzipain) and Leishmania spp. (gp63). In this work, a population of P. serpens resistant to the calpain inhibitor MDL28170 at 70 µ m (MDLR population) was selected by culturing promastigotes in increasing concentrations of the drug. The only relevant ultrastructural difference between wild-type (WT) and MDLR promastigotes was the presence of microvesicles within the flagellar pocket of the latter. MDLR population also showed an increased reactivity to anti-cruzipain antibody as well as a higher papain-like proteolytic activity, while the expression of calpain-like molecules cross-reactive to anti-Dm-calpain (from Drosophila melanogaster) antibody and calcium-dependent cysteine peptidase activity were decreased. Gp63-like molecules also presented a diminished expression in MDLR population, which is probably correlated to the reduction in the parasite adhesion to the salivary glands of the insect vector Oncopeltus fasciatus. A lower accumulation of Rhodamine 123 was detected in MDLR cells when compared with the WT population, a phenotype that was reversed when MDLR cells were treated with cyclosporin A and verapamil. Collectively, our results may help in the understanding of the roles of calpain inhibitors in trypanosomatids.
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21
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The Lipid Raft Proteome of African Trypanosomes Contains Many Flagellar Proteins. Pathogens 2017; 6:pathogens6030039. [PMID: 28837104 PMCID: PMC5617996 DOI: 10.3390/pathogens6030039] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Revised: 08/22/2017] [Accepted: 08/22/2017] [Indexed: 12/20/2022] Open
Abstract
Lipid rafts are liquid-ordered membrane microdomains that form by preferential association of 3-β-hydroxysterols, sphingolipids and raft-associated proteins often having acyl modifications. We isolated lipid rafts of the protozoan parasite Trypanosoma brucei and determined the protein composition of lipid rafts in the cell. This analysis revealed a striking enrichment of flagellar proteins and several putative signaling proteins in the lipid raft proteome. Calpains and intraflagellar transport proteins, in particular, were found to be abundant in the lipid raft proteome. These findings provide additional evidence supporting the notion that the eukaryotic cilium/flagellum is a lipid raft-enriched specialized structure with high concentrations of sterols, sphingolipids and palmitoylated proteins involved in environmental sensing and cell signaling.
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22
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Brown RWB, Sharma AI, Engman DM. Dynamic protein S-palmitoylation mediates parasite life cycle progression and diverse mechanisms of virulence. Crit Rev Biochem Mol Biol 2017; 52:145-162. [PMID: 28228066 PMCID: PMC5560270 DOI: 10.1080/10409238.2017.1287161] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Eukaryotic parasites possess complex life cycles and utilize an assortment of molecular mechanisms to overcome physical barriers, suppress and/or bypass the host immune response, including invading host cells where they can replicate in a protected intracellular niche. Protein S-palmitoylation is a dynamic post-translational modification in which the fatty acid palmitate is covalently linked to cysteine residues on proteins by the enzyme palmitoyl acyltransferase (PAT) and can be removed by lysosomal palmitoyl-protein thioesterase (PPT) or cytosolic acyl-protein thioesterase (APT). In addition to anchoring proteins to intracellular membranes, functions of dynamic palmitoylation include - targeting proteins to specific intracellular compartments via trafficking pathways, regulating the cycling of proteins between membranes, modulating protein function and regulating protein stability. Recent studies in the eukaryotic parasites - Plasmodium falciparum, Toxoplasma gondii, Trypanosoma brucei, Cryptococcus neoformans and Giardia lamblia - have identified large families of PATs and palmitoylated proteins. Many palmitoylated proteins are important for diverse aspects of pathogenesis, including differentiation into infective life cycle stages, biogenesis and tethering of secretory organelles, assembling the machinery powering motility and targeting virulence factors to the plasma membrane. This review aims to summarize our current knowledge of palmitoylation in eukaryotic parasites, highlighting five exemplary mechanisms of parasite virulence dependent on palmitoylation.
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Affiliation(s)
- Robert W. B. Brown
- Department of Pathology and Laboratory Medicine, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Aabha I. Sharma
- Departments of Pathology and Microbiology-Biology, Northwestern University, Chicago, IL, United States
| | - David M. Engman
- Department of Pathology and Laboratory Medicine, Cedars-Sinai Medical Center, Los Angeles, CA, United States
- Departments of Pathology and Microbiology-Biology, Northwestern University, Chicago, IL, United States
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23
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Oliveira SSCD, Gonçalves DDS, Garcia-Gomes ADS, Gonçalves IC, Seabra SH, Menna-Barreto RF, Lopes AHDCS, D'Avila-Levy CM, Santos ALSD, Branquinha MH. Susceptibility of Phytomonas serpens to calpain inhibitors in vitro: interference on the proliferation, ultrastructure, cysteine peptidase expression and interaction with the invertebrate host. Mem Inst Oswaldo Cruz 2016; 112:31-43. [PMID: 27925020 PMCID: PMC5224352 DOI: 10.1590/0074-02760160270] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 09/12/2016] [Indexed: 12/15/2022] Open
Abstract
A pleiotropic response to the calpain inhibitor MDL28170 was detected in the tomato
parasite Phytomonas serpens. Ultrastructural studies revealed that
MDL28170 caused mitochondrial swelling, shortening of flagellum and disruption of
trans Golgi network. This effect was correlated to the inhibition in processing of
cruzipain-like molecules, which presented an increase in expression paralleled by
decreased proteolytic activity. Concomitantly, a calcium-dependent cysteine peptidase
was detected in the parasite extract, the activity of which was repressed by
pre-incubation of parasites with MDL28170. Flow cytometry and Western blotting
analyses revealed the differential expression of calpain-like proteins (CALPs) in
response to the pre-incubation of parasites with the MDL28170, and confocal
fluorescence microscopy confirmed their surface location. The interaction of
promastigotes with explanted salivary glands of the insect Oncopeltus
fasciatus was reduced when parasites were pre-treated with MDL28170,
which was correlated to reduced levels of surface cruzipain-like and gp63-like
molecules. Treatment of parasites with anti-Drosophila melanogaster
(Dm) calpain antibody also decreased the adhesion process. Additionally, parasites
recovered from the interaction process presented higher levels of surface
cruzipain-like and gp63-like molecules, with similar levels of CALPs cross-reactive
to anti-Dm-calpain antibody. The results confirm the importance of exploring the use
of calpain inhibitors in studying parasites’ physiology.
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Affiliation(s)
- Simone Santiago Carvalho de Oliveira
- Universidade Federal do Rio de Janeiro, Instituto de Microbiologia Paulo de Góes, Departamento de Microbiologia Geral, Laboratório de Investigação de Peptidases, Rio de Janeiro, RJ, Brasil
| | - Diego de Souza Gonçalves
- Universidade Federal do Rio de Janeiro, Instituto de Química, Programa de Pós-Graduação em Bioquímica, Rio de Janeiro, RJ, Brasil
| | - Aline Dos Santos Garcia-Gomes
- Fundação Oswaldo Cruz, Instituto Oswaldo Cruz, Laboratório de Estudos Integrados em Protozoologia, Coleção de Protozoários, Rio de Janeiro, RJ, Brasil.,Instituto Federal de Educação, Ciência e Tecnologia, Laboratório de Microbiologia, Rio de Janeiro, RJ, Brasil
| | - Inês Correa Gonçalves
- Universidade Federal do Rio de Janeiro, Instituto de Microbiologia Paulo de Góes, Departamento de Microbiologia Geral, Laboratório de Bioquímica de Microrganismos, Rio de Janeiro, RJ, Brasil
| | - Sergio Henrique Seabra
- Centro Universitário Estadual da Zona Oeste, Laboratório de Tecnologia em Cultura de Células, Rio de Janeiro, RJ, Brasil
| | | | - Angela Hampshire de Carvalho Santos Lopes
- Universidade Federal do Rio de Janeiro, Instituto de Microbiologia Paulo de Góes, Departamento de Microbiologia Geral, Laboratório de Bioquímica de Microrganismos, Rio de Janeiro, RJ, Brasil
| | - Claudia Masini D'Avila-Levy
- Fundação Oswaldo Cruz, Instituto Oswaldo Cruz, Laboratório de Estudos Integrados em Protozoologia, Coleção de Protozoários, Rio de Janeiro, RJ, Brasil
| | - André Luis Souza Dos Santos
- Universidade Federal do Rio de Janeiro, Instituto de Microbiologia Paulo de Góes, Departamento de Microbiologia Geral, Laboratório de Investigação de Peptidases, Rio de Janeiro, RJ, Brasil.,Universidade Federal do Rio de Janeiro, Instituto de Química, Programa de Pós-Graduação em Bioquímica, Rio de Janeiro, RJ, Brasil
| | - Marta Helena Branquinha
- Universidade Federal do Rio de Janeiro, Instituto de Microbiologia Paulo de Góes, Departamento de Microbiologia Geral, Laboratório de Investigação de Peptidases, Rio de Janeiro, RJ, Brasil
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Roberts AJ, Fairlamb AH. The N-myristoylome of Trypanosoma cruzi. Sci Rep 2016; 6:31078. [PMID: 27492267 PMCID: PMC4974623 DOI: 10.1038/srep31078] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Accepted: 07/12/2016] [Indexed: 01/04/2023] Open
Abstract
Protein N-myristoylation is catalysed by N-myristoyltransferase (NMT), an essential and druggable target in Trypanosoma cruzi, the causative agent of Chagas' disease. Here we have employed whole cell labelling with azidomyristic acid and click chemistry to identify N-myristoylated proteins in different life cycle stages of the parasite. Only minor differences in fluorescent-labelling were observed between the dividing forms (the insect epimastigote and mammalian amastigote stages) and the non-dividing trypomastigote stage. Using a combination of label-free and stable isotope labelling of cells in culture (SILAC) based proteomic strategies in the presence and absence of the NMT inhibitor DDD85646, we identified 56 proteins enriched in at least two out of the three experimental approaches. Of these, 6 were likely to be false positives, with the remaining 50 commencing with amino acids MG at the N-terminus in one or more of the T. cruzi genomes. Most of these are proteins of unknown function (32), with the remainder (18) implicated in a diverse range of critical cellular and metabolic functions such as intracellular transport, cell signalling and protein turnover. In summary, we have established that 0.43-0.46% of the proteome is N-myristoylated in T. cruzi approaching that of other eukaryotic organisms (0.5-1.7%).
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Affiliation(s)
- Adam J. Roberts
- Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK
| | - Alan H. Fairlamb
- Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK
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25
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Wright MH, Paape D, Price HP, Smith DF, Tate EW. Global Profiling and Inhibition of Protein Lipidation in Vector and Host Stages of the Sleeping Sickness Parasite Trypanosoma brucei. ACS Infect Dis 2016; 2:427-441. [PMID: 27331140 PMCID: PMC4906374 DOI: 10.1021/acsinfecdis.6b00034] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2016] [Indexed: 01/05/2023]
Abstract
The enzyme N-myristoyltransferase (NMT) catalyzes the essential fatty acylation of substrate proteins with myristic acid in eukaryotes and is a validated drug target in the parasite Trypanosoma brucei, the causative agent of African trypanosomiasis (sleeping sickness). N-Myristoylation typically mediates membrane localization of proteins and is essential to the function of many. However, only a handful of proteins are experimentally validated as N-myristoylated in T. brucei. Here, we perform metabolic labeling with an alkyne-tagged myristic acid analogue, enabling the capture of lipidated proteins in insect and host life stages of T. brucei. We further compare this with a longer chain palmitate analogue to explore the chain length-specific incorporation of fatty acids into proteins. Finally, we combine the alkynyl-myristate analogue with NMT inhibitors and quantitative chemical proteomics to globally define N-myristoylated proteins in the clinically relevant bloodstream form parasites. This analysis reveals five ARF family small GTPases, calpain-like proteins, phosphatases, and many uncharacterized proteins as substrates of NMT in the parasite, providing a global view of the scope of this important protein modification and further evidence for the crucial and pleiotropic role of NMT in the cell.
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Affiliation(s)
- Megan H. Wright
- Department of Chemistry, Imperial College London, London SW7 2AZ, United Kingdom
| | - Daniel Paape
- Centre for Immunology and Infection, Department
of Biology, University of York, York YO10 5DD, United Kingdom
| | - Helen P. Price
- Centre for Immunology and Infection, Department
of Biology, University of York, York YO10 5DD, United Kingdom
| | - Deborah F. Smith
- Centre for Immunology and Infection, Department
of Biology, University of York, York YO10 5DD, United Kingdom
| | - Edward W. Tate
- Department of Chemistry, Imperial College London, London SW7 2AZ, United Kingdom
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26
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Monroy VS, Flores OM, García CG, Maya YC, Fernández TD, Pérez Ishiwara DG. Calpain-like: A Ca(2+) dependent cystein protease in Entamoeba histolytica cell death. Exp Parasitol 2015; 159:245-51. [PMID: 26496790 DOI: 10.1016/j.exppara.2015.10.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Revised: 09/08/2015] [Accepted: 10/19/2015] [Indexed: 10/22/2022]
Abstract
Entamoeba histolytica programmed cell death (PCD) induced by G418 is characterized by the release of important amounts of intracellular calcium from reservoirs. Nevertheless, no typical caspases have been detected in the parasite, the PCD phenotype is inhibited by the cysteine protease inhibitor E-64. These results strongly suggest that Ca(2+)-dependent proteases could be involved in PCD. In this study, we evaluate the expression and activity of a specific dependent Ca(2+) protease, the calpain-like protease, by real-time quantitative PCR (RTq-PCR), Western blot assays and a enzymatic method during the induction of PCD by G418. Alternatively, using cell viability and TUNEL assays, we also demonstrated that the Z-Leu-Leu-Leu-al calpain inhibitor reduced the rate of cell death. The results demonstrated 4.9-fold overexpression of calpain-like gene 1.5 h after G418 PCD induction, while calpain-like protein increased almost two-fold with respect to basal calpain-like expression after 3 h of induction, and calpain activity was found to be approximately three-fold higher 6 h after treatment compared with untreated trophozoites. Taken together, these results suggest that this Ca(2+)-dependent protease could be involved in the executory phase of PCD.
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Affiliation(s)
- Virginia Sánchez Monroy
- Laboratorio de Biomedicina Molecular I, Programa Institucional de Biomedicina Molecular, Escuela Nacional de Medicina y Homeopatía, IPN, Guillermo Massieu Helguera No.239, Fracc. La Escalera, Col. Ticomán, D.F, C.P.07320, Mexico; Laboratorio Multidisciplinario de Investigación, Escuela Militar de Graduados de Sanidad, UDEFA, Lomas de San Isidro, DF, CP 11620, Mexico
| | - Olivia Medel Flores
- Laboratorio de Biomedicina Molecular I, Programa Institucional de Biomedicina Molecular, Escuela Nacional de Medicina y Homeopatía, IPN, Guillermo Massieu Helguera No.239, Fracc. La Escalera, Col. Ticomán, D.F, C.P.07320, Mexico
| | - Consuelo Gómez García
- Laboratorio de Biomedicina Molecular I, Programa Institucional de Biomedicina Molecular, Escuela Nacional de Medicina y Homeopatía, IPN, Guillermo Massieu Helguera No.239, Fracc. La Escalera, Col. Ticomán, D.F, C.P.07320, Mexico
| | - Yesenia Chávez Maya
- Facultad de Estudios Superiores Cuautitlán Izcalli, UNAM, Cuautitlán Izcalli, Estado de México CP.54740, Mexico
| | - Tania Domínguez Fernández
- Laboratorio de Biomedicina Molecular I, Programa Institucional de Biomedicina Molecular, Escuela Nacional de Medicina y Homeopatía, IPN, Guillermo Massieu Helguera No.239, Fracc. La Escalera, Col. Ticomán, D.F, C.P.07320, Mexico
| | - D Guillermo Pérez Ishiwara
- Laboratorio de Biomedicina Molecular I, Programa Institucional de Biomedicina Molecular, Escuela Nacional de Medicina y Homeopatía, IPN, Guillermo Massieu Helguera No.239, Fracc. La Escalera, Col. Ticomán, D.F, C.P.07320, Mexico; Centro de Investigación en Ciencia Aplicada. Instituto Politécnico Nacional, Tepetitla de Lardizabal, Tlaxcala, Doctorado en Biotecnología, Red de Investigación en Biotecnología IPN, Mexico.
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de Oliveira SSC, Garcia-Gomes ADS, d'Avila-Levy CM, dos Santos ALS, Branquinha MH. Expression of calpain-like proteins and effects of calpain inhibitors on the growth rate of Angomonas deanei wild type and aposymbiotic strains. BMC Microbiol 2015; 15:188. [PMID: 26415499 PMCID: PMC4587752 DOI: 10.1186/s12866-015-0519-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Accepted: 09/16/2015] [Indexed: 12/21/2022] Open
Abstract
Background Angomonas deanei is a trypanosomatid parasite of insects that has a bacterial endosymbiont, which supplies amino acids and other nutrients to its host. Bacterium loss induced by antibiotic treatment of the protozoan leads to an aposymbiotic strain with increased need for amino acids and results in increased production of extracellular peptidases. In this work, a more detailed examination of A. deanei was conducted to determine the effects of endosymbiont loss on the host calpain-like proteins (CALPs), followed by testing of different calpain inhibitors on parasite proliferation. Results Western blotting showed the presence of different protein bands reactive to antibodies against calpain from Drosophila melanogaster (anti-Dm-calpain), lobster calpain (anti-CDPIIb) and cytoskeleton-associated calpain from Trypanosoma brucei (anti-CAP5.5), suggesting a possible modulation of CALPs influenced by the endosymbiont. In the cell-free culture supernatant of A. deanei wild type and aposymbiotic strains, a protein of 80 kDa cross-reacted with the anti-Dm-calpain antibody; however, no cross-reactivity was found with anti-CAP5.5 and anti-CDPIIb antibodies. A search in A. deanei genome for homologues of D. melanogaster calpain, T. brucei CAP5.5 and lobster CDPIIb calpain revealed the presence of hits with at least one calpain conserved domain and also with theoretical molecular mass consistent with the recognition by each antibody. No significant hit was observed in the endosymbiont genome, indicating that calpain molecules might be absent from the symbiont. Flow cytometry analysis of cells treated with the anti-calpain antibodies showed that a larger amount of reactive epitopes was located intracellularly. The reversible calpain inhibitor MDL28170 displayed a much higher efficacy in diminishing the growth of both strains compared to the non-competitive calpain inhibitor PD150606, while the irreversible calpain inhibitor V only marginally diminished the proliferation. Conclusions Altogether, these results indicate that distinct calpain-like molecules are expressed by A. deanei, with a possible modulation in the expression influenced by the endosymbiont. In addition, treatment with MDL28170 affects the growth rate of both strains, as previously determined in the human pathogenic species Leishmania amazonensis and Trypanosoma cruzi, with whom A. deanei shares immunological and biochemical relationships.
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Affiliation(s)
- Simone Santiago Carvalho de Oliveira
- Laboratório de Investigação de Peptidases, Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil.
| | - Aline dos Santos Garcia-Gomes
- Laboratório de Estudos Integrados em Protozoologia, Coleção de Protozoários, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil. .,Laboratório de Microbiologia, Instituto Federal de Educação, Ciência e Tecnologia - Campus Rio de Janeiro, Rio de Janeiro, Brazil.
| | - Claudia Masini d'Avila-Levy
- Laboratório de Estudos Integrados em Protozoologia, Coleção de Protozoários, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.
| | - André Luis Souza dos Santos
- Laboratório de Investigação de Peptidases, Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Marta Helena Branquinha
- Laboratório de Investigação de Peptidases, Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil.
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28
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Wright MH, Paape D, Storck EM, Serwa RA, Smith DF, Tate EW. Global analysis of protein N-myristoylation and exploration of N-myristoyltransferase as a drug target in the neglected human pathogen Leishmania donovani. ACTA ACUST UNITED AC 2015; 22:342-54. [PMID: 25728269 PMCID: PMC4372256 DOI: 10.1016/j.chembiol.2015.01.003] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Revised: 12/16/2014] [Accepted: 01/13/2015] [Indexed: 10/26/2022]
Abstract
N-Myristoyltransferase (NMT) modulates protein function through the attachment of the lipid myristate to the N terminus of target proteins, and is a promising drug target in eukaryotic parasites such as Leishmania donovani. Only a small number of NMT substrates have been characterized in Leishmania, and a global picture of N-myristoylation is lacking. Here, we use metabolic tagging with an alkyne-functionalized myristic acid mimetic in live parasites followed by downstream click chemistry and analysis to identify lipidated proteins in both the promastigote (extracellular) and amastigote (intracellular) life stages. Quantitative chemical proteomics is used to profile target engagement by NMT inhibitors, and to define the complement of N-myristoylated proteins. Our results provide new insight into the multiple pathways modulated by NMT and the pleiotropic effects of NMT inhibition. This work constitutes the first global experimental analysis of protein lipidation in Leishmania, and reveals the extent of NMT-related biology yet to be explored for this neglected human pathogen.
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Affiliation(s)
- Megan H Wright
- Department of Chemistry, Imperial College London, London SW7 2AZ, UK.
| | - Daniel Paape
- Centre for Immunology and Infection, Department of Biology, University of York, York YO10 5DD, UK
| | | | - Remigiusz A Serwa
- Department of Chemistry, Imperial College London, London SW7 2AZ, UK
| | - Deborah F Smith
- Centre for Immunology and Infection, Department of Biology, University of York, York YO10 5DD, UK
| | - Edward W Tate
- Department of Chemistry, Imperial College London, London SW7 2AZ, UK.
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29
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Portman N, Gull K. Identification of paralogous life-cycle stage specific cytoskeletal proteins in the parasite Trypanosoma brucei. PLoS One 2014; 9:e106777. [PMID: 25180513 PMCID: PMC4152294 DOI: 10.1371/journal.pone.0106777] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Accepted: 08/07/2014] [Indexed: 12/03/2022] Open
Abstract
The life cycle of the African trypanosome Trypanosoma brucei, is characterised by a transition between insect and mammalian hosts representing very different environments that present the parasite with very different challenges. These challenges are met by the expression of life-cycle stage-specific cohorts of proteins, which function in systems such as metabolism and immune evasion. These life-cycle transitions are also accompanied by morphological rearrangements orchestrated by microtubule dynamics and associated proteins of the subpellicular microtubule array. Here we employed a gel-based comparative proteomic technique, Difference Gel Electrophoresis, to identify cytoskeletal proteins that are expressed differentially in mammalian infective and insect form trypanosomes. From this analysis we identified a pair of novel, paralogous proteins, one of which is expressed in the procyclic form and the other in the bloodstream form. We show that these proteins, CAP51 and CAP51V, localise to the subpellicular corset of microtubules and are essential for correct organisation of the cytoskeleton and successful cytokinesis in their respective life cycle stages. We demonstrate for the first time redundancy of function between life-cycle stage specific paralogous sets in the cytoskeleton and reveal modification of cytoskeletal components in situ prior to their removal during differentiation from the bloodstream form to the insect form. These specific results emphasise a more generic concept that the trypanosome genome encodes a cohort of cytoskeletal components that are present in at least two forms with life-cycle stage-specific expression.
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Affiliation(s)
- Neil Portman
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
- Faculty of Veterinary Science, University of Sydney, Sydney, Australia
- * E-mail:
| | - Keith Gull
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
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Abstract
A decade of genome sequencing has transformed our understanding of how
trypanosomatid parasites have evolved and provided fresh impetus to explaining
the origins of parasitism in the Kinetoplastida. In this review, I will consider
the many ways in which genome sequences have influenced our view of genomic
reduction in trypanosomatids; how species-specific genes, and the genomic
domains they occupy, have illuminated the innovations in trypanosomatid genomes;
and how comparative genomics has exposed the molecular mechanisms responsible
for innovation and adaptation to a parasitic lifestyle.
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31
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Goldston AM, Sharma AI, Paul KS, Engman DM. Acylation in trypanosomatids: an essential process and potential drug target. Trends Parasitol 2014; 30:350-60. [PMID: 24954795 DOI: 10.1016/j.pt.2014.05.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Revised: 05/06/2014] [Accepted: 05/06/2014] [Indexed: 12/11/2022]
Abstract
Fatty acylation--the addition of fatty acid moieties such as myristate and palmitate to proteins--is essential for the survival, growth, and infectivity of the trypanosomatids: Trypanosoma brucei, Trypanosoma cruzi, and Leishmania. Myristoylation and palmitoylation are critical for parasite growth, targeting and localization, and the intrinsic function of some proteins. The trypanosomatids possess a single N-myristoyltransferase (NMT) and multiple palmitoyl acyltransferases, and these enzymes and their protein targets are only now being characterized. Global inhibition of either process leads to cell death in trypanosomatids, and genetic ablation of NMT compromises virulence. Moreover, NMT inhibitors effectively cure T. brucei infection in rodents. Thus, protein acylation represents an attractive target for the development of new trypanocidal drugs.
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Affiliation(s)
- Amanda M Goldston
- Departments of Pathology and Microbiology-Immunology, Northwestern University, Chicago, Illinois, USA
| | - Aabha I Sharma
- Departments of Pathology and Microbiology-Immunology, Northwestern University, Chicago, Illinois, USA
| | - Kimberly S Paul
- Department of Genetics and Biochemistry, Clemson University, Clemson, South Carolina, USA
| | - David M Engman
- Departments of Pathology and Microbiology-Immunology, Northwestern University, Chicago, Illinois, USA.
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32
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Roberts A, Torrie L, Wyllie S, Fairlamb A. Biochemical and genetic characterization of Trypanosoma cruzi N-myristoyltransferase. Biochem J 2014; 459:323-32. [PMID: 24444291 PMCID: PMC3969225 DOI: 10.1042/bj20131033] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Revised: 01/20/2014] [Accepted: 01/21/2014] [Indexed: 12/20/2022]
Abstract
Co- and post-translational N-myristoylation is known to play a role in the correct subcellular localization of specific proteins in eukaryotes. The enzyme that catalyses this reaction, NMT (N-myristoyltransferase), has been pharmacologically validated as a drug target in the African trypanosome, Trypanosoma brucei. In the present study, we evaluate NMT as a potential drug target in Trypanosoma cruzi, the causative agent of Chagas' disease, using chemical and genetic approaches. Replacement of both allelic copies of TcNMT (T. cruzi NMT) was only possible in the presence of a constitutively expressed ectopic copy of the gene, indicating that this gene is essential for survival of T. cruzi epimastigotes. The pyrazole sulphonamide NMT inhibitor DDD85646 is 13-23-fold less potent against recombinant TcNMT than TbNMT (T. brucei NMT), with Ki values of 12.7 and 22.8 nM respectively, by scintillation proximity or coupled assay methods. DDD85646 also inhibits growth of T. cruzi epimastigotes (EC50=6.9 μM), but is ~1000-fold less potent than that reported for T. brucei. On-target activity is demonstrated by shifts in cell potency in lines that over- and under-express NMT and by inhibition of intracellular N-myristoylation of several proteins in a dose-dependent manner. Collectively, our findings suggest that N-myristoylation is an essential and druggable target in T. cruzi.
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Key Words
- chagas’ disease
- click chemistry
- drug target
- n-myristoylation
- trypanosoma cruzi
- validation
- cap5.5, cytoskeleton-associated protein 5.5
- dig, digoxigenin
- dko, double knockout
- dmem, dulbecco’s modified eagle’s medium
- hyg, hygromycin phosphotransferase
- nmt, n-myristoyltransferase
- nmtoe, nmt overexpressor
- pac, puromycin n-acetyltransferase
- rth/fbs, rpmi 1640 medium supplemented with trypticase, haemin, hepes and 10% heat-inactivated fbs
- sko, single knockout
- tbnmt, trypanosoma brucei nmt
- tcep, tris-(2-carboxyethyl)phosphine
- tcnmt, trypanosoma cruzi nmt
- tctryr, trypanosoma cruzi trypanothione reductase
- wt, wild-type
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Affiliation(s)
- Adam J. Roberts
- *Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee DD1 5EH, U.K
| | - Leah S. Torrie
- *Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee DD1 5EH, U.K
| | - Susan Wyllie
- *Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee DD1 5EH, U.K
| | - Alan H. Fairlamb
- *Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee DD1 5EH, U.K
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The calpain inhibitor MDL28170 induces the expression of apoptotic markers in Leishmania amazonensis promastigotes. PLoS One 2014; 9:e87659. [PMID: 24498160 PMCID: PMC3909198 DOI: 10.1371/journal.pone.0087659] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2013] [Accepted: 12/26/2013] [Indexed: 11/19/2022] Open
Abstract
Background Human cutaneous leishmaniasis is caused by distinct species, including Leishmania amazonensis. Treatment of cutaneous leishmaniasis is far from satisfactory due to increases in drug resistance and relapses, and toxicity of compounds to the host. As a consequence for this situation, the development of new leishmanicidal drugs and the search of new targets in the parasite biology are important goals. Methodology/Principal Findings In this study, we investigated the mechanism of death pathway induced by the calpain inhibitor MDL28170 on Leishmania amazonensis promastigote forms. The combined use of different techniques was applied to contemplate this goal. MDL28170 treatment with IC50 (15 µM) and two times the IC50 doses induced loss of parasite viability, as verified by resazurin assay, as well as depolarization of the mitochondrial membrane, which was quantified by JC-1 staining. Scanning and transmission electron microscopic images revealed drastic alterations on the parasite morphology, some of them resembling apoptotic-like death, including cell shrinking, surface membrane blebs and altered chromatin condensation pattern. The lipid rearrangement of the plasma membrane was detected by Annexin-V labeling. The inhibitor also induced a significant increase in the proportion of cells in the sub-G0/G1 phase, as quantified by propidium iodide staining, as well as genomic DNA fragmentation, detected by TUNEL assay. In cells treated with MDL28170 at two times the IC50 dose, it was also possible to observe an oligonucleossomal DNA fragmentation by agarose gel electrophoresis. Conclusions/Significance The data presented in the current study suggest that MDL28170 induces apoptotic marker expression in promastigotes of L. amazonensis. Altogether, the results described in the present work not only provide a rationale for further exploration of the mechanism of action of calpain inhibitors against trypanosomatids, but may also widen the investigation of the potential clinical utility of calpain inhibitors in the chemotherapy of leishmaniases.
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Tate EW, Bell AS, Rackham MD, Wright MH. N-Myristoyltransferase as a potential drug target in malaria and leishmaniasis. Parasitology 2014; 141:37-49. [PMID: 23611109 DOI: 10.1017/s0031182013000450] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Infections caused by protozoan parasites are among the most widespread and intractable transmissible diseases affecting the developing world, with malaria and leishmaniasis being the most costly in terms of morbidity and mortality. Although new drugs are urgently required against both diseases in the face of ever-rising resistance to frontline therapies, very few candidates passing through development pipelines possess a known and novel mode of action. Set in the context of drugs currently in use and under development, we present the evidence for N-myristoyltransferase (NMT), an enzyme that N-terminally lipidates a wide range of specific target proteins through post-translational modification, as a potential drug target in malaria and the leishmaniases. We discuss the limitations of current knowledge regarding the downstream targets of this enzyme in protozoa, and our recent progress towards potent cell-active NMT inhibitors against the most clinically-relevant species of parasite. Finally, we outline the next steps required in terms of both tools to understand N-myristoylation in protozoan parasites, and the generation of potential development candidates based on the output of our recently-reported high-throughput screens.
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Affiliation(s)
- Edward W Tate
- Department of Chemistry, Institute of Chemical Biology, Imperial College London, London SW7 2AZ, UK
| | - Andrew S Bell
- Department of Chemistry, Institute of Chemical Biology, Imperial College London, London SW7 2AZ, UK
| | - Mark D Rackham
- Department of Chemistry, Institute of Chemical Biology, Imperial College London, London SW7 2AZ, UK
| | - Megan H Wright
- Department of Chemistry, Institute of Chemical Biology, Imperial College London, London SW7 2AZ, UK
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35
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Wheeler RJ, Gluenz E, Gull K. The limits on trypanosomatid morphological diversity. PLoS One 2013; 8:e79581. [PMID: 24260255 PMCID: PMC3834336 DOI: 10.1371/journal.pone.0079581] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Accepted: 10/02/2013] [Indexed: 01/13/2023] Open
Abstract
Cell shape is one, often overlooked, way in which protozoan parasites have adapted to a variety of host and vector environments and directional transmissions between these environments. Consequently, different parasite life cycle stages have characteristic morphologies. Trypanosomatid parasites are an excellent example of this in which large morphological variations between species and life cycle stage occur, despite sharing well-conserved cytoskeletal and membranous structures. Here, using previously published reports in the literature of the morphology of 248 isolates of trypanosomatid species from different hosts, we perform a meta-analysis of the occurrence and limits on morphological diversity of different classes of trypanosomatid morphology (trypomastigote, promastigote, etc.) in the vertebrate bloodstream and invertebrate gut environments. We identified several limits on cell body length, cell body width and flagellum length diversity which can be interpreted as biomechanical limits on the capacity of the cell to attain particular dimensions. These limits differed for morphologies with and without a laterally attached flagellum which we suggest represent two morphological superclasses, the ‘juxtaform’ and ‘liberform’ superclasses. Further limits were identified consistent with a selective pressure from the mechanical properties of the vertebrate bloodstream environment; trypanosomatid size showed limits relative to host erythrocyte dimensions. This is the first comprehensive analysis of the limits of morphological diversity in any protozoan parasite, revealing the morphogenetic constraints and extrinsic selection pressures associated with the full diversity of trypanosomatid morphology.
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Affiliation(s)
- Richard John Wheeler
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
- * E-mail:
| | - Eva Gluenz
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Keith Gull
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
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Ooi CP, Bastin P. More than meets the eye: understanding Trypanosoma brucei morphology in the tsetse. Front Cell Infect Microbiol 2013; 3:71. [PMID: 24312899 PMCID: PMC3826061 DOI: 10.3389/fcimb.2013.00071] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Accepted: 10/14/2013] [Indexed: 11/13/2022] Open
Abstract
T. brucei, the causative parasite for African trypanosomiasis, faces an interesting dilemma in its life cycle. It has to successfully complete its infection cycle in the tsetse vector to be able to infect other vertebrate hosts. T. brucei has to undergo multiple morphological changes as it invades the alimentary canal of the tsetse to finally achieve infectivity in the salivary glands. In this review, we attempt to elucidate how these morphological changes are possible for a parasite that has evolved a highly robust cell structure to survive the chemically and physically diverse environments it finds itself in. To achieve this, we juxtaposed the experimental evidence that has been collected from T. brucei forms that are cultured in vitro with the observations that have been carried out on tsetse-infective forms in vivo. Although the accumulated knowledge on T. brucei biology is by no means trivial, several outstanding questions remain for how the parasite mechanistically changes its morphology as it traverses the tsetse and how those changes are triggered. However, we conclude that with recent breakthroughs allowing for the replication of the tsetse-infection process of T. brucei in vitro, these outstanding questions can finally be addressed.
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Affiliation(s)
| | - Philippe Bastin
- Trypanosome Cell Biology Unit, CNRS URA2581, Institut PasteurParis, France
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Heng J, Saunders EC, Gooley PR, McConville MJ, Naderer T, Tull D. Membrane targeting of the small myristoylated protein 2 (SMP-2) in Leishmania major. Mol Biochem Parasitol 2013; 190:1-5. [PMID: 23727225 DOI: 10.1016/j.molbiopara.2013.05.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Revised: 05/06/2013] [Accepted: 05/21/2013] [Indexed: 01/01/2023]
Abstract
Leishmania parasites express three highly conserved small myristoylated proteins (SMPs) that are targeted to distinct membranes. SMP-1 is exclusively found in the flagellum, depending on myristoylation and palmitoylation. In contrast, monoacylated SMP-2 and SMP-4 are localized to the flagellar pocket and plasma membrane, respectively. Here, we demonstrate that unlike SMP-4, SMP-2 resides in detergent resistant membranes, but can be readily solubilized in the presence of high concentrations of salt. We provide evidence that in detergent resistant membranes, SMP-2 forms high molecular weight complexes in vivo. Association with detergent resistant membranes was abrogated in the presence of a C-terminal tag suggesting acylation independent targeting signals. In addition, the N-terminal region of SMP-2 contains sufficient information for membrane targeting, as a GFP-chimera localizes to the flagellar pocket. Thus while the core sequences of the SMPs are highly conserved, individual members have evolved different mechanisms for their diverse membrane localization.
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Affiliation(s)
- Joanne Heng
- Department of Biochemistry and Molecular Biology, Bio21 Institute of Molecular Science and Biotechnology, University of Melbourne, Parkville, Victoria, Australia
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Branquinha MH, Marinho FA, Sangenito LS, Oliveira SSC, Goncalves KC, Ennes-Vidal V, d'Avila-Levy CM, Santos ALS. Calpains: potential targets for alternative chemotherapeutic intervention against human pathogenic trypanosomatids. Curr Med Chem 2013; 20:3174-85. [PMID: 23899207 PMCID: PMC4181241 DOI: 10.2174/0929867311320250010] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2012] [Revised: 01/29/2013] [Accepted: 02/13/2013] [Indexed: 12/03/2022]
Abstract
The treatment for both leishmaniasis and trypanosomiasis, which are severe human infections caused by trypanosomatids belonging to Leishmania and Trypanosoma genera, respectively, is extremely limited because of concerns of toxicity and efficacy with the available anti-protozoan drugs, as well as the emergence of drug resistance. Consequently, the urgency for the discovery of new trypanosomatid targets and novel bioactive compounds is particularly necessary. In this context, the investigation of changes in parasite gene expression between drug resistant/sensitive strains and in the up-regulation of virulence-related genes in infective forms has brought to the fore the involvement of calpain-like proteins in several crucial pathophysiological processes performed by trypanosomatids. These studies were encouraged by the publication of the complete genome sequences of three human pathogenic trypanosomatids, Trypanosoma brucei, Trypanosoma cruzi and Leishmania major, which allowed in silico analyses that in turn directed the identification of numerous genes with interesting chemotherapeutic characteristics, including a large family of calpain-related proteins, in which to date 23 genes were assigned as calpains in T. brucei, 40 in T. cruzi and 33 in L. braziliensis. In the present review, we intend to add to these biochemical/biological reports the investigations performed upon the inhibitory capability of calpain inhibitors against human pathogenic trypanosomatids.
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Affiliation(s)
- M H Branquinha
- Laboratório de Investigação de Peptidases, Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes-IMPG, Centro de Ciências da Saúde-CCS, Bloco Esubsolo, Sala 05, Universidade Federal do Rio de Janeiro-UFRJ, Rio de Janeiro, Brazil.
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Selective inhibitors of protozoan protein N-myristoyltransferases as starting points for tropical disease medicinal chemistry programs. PLoS Negl Trop Dis 2012; 6:e1625. [PMID: 22545171 PMCID: PMC3335879 DOI: 10.1371/journal.pntd.0001625] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2011] [Accepted: 03/07/2012] [Indexed: 01/11/2023] Open
Abstract
Inhibition of N-myristoyltransferase has been validated pre-clinically as a target for the treatment of fungal and trypanosome infections, using species-specific inhibitors. In order to identify inhibitors of protozoan NMTs, we chose to screen a diverse subset of the Pfizer corporate collection against Plasmodium falciparum and Leishmania donovani NMTs. Primary screening hits against either enzyme were tested for selectivity over both human NMT isoforms (Hs1 and Hs2) and for broad-spectrum anti-protozoan activity against the NMT from Trypanosoma brucei. Analysis of the screening results has shown that structure-activity relationships (SAR) for Leishmania NMT are divergent from all other NMTs tested, a finding not predicted by sequence similarity calculations, resulting in the identification of four novel series of Leishmania-selective NMT inhibitors. We found a strong overlap between the SARs for Plasmodium NMT and both human NMTs, suggesting that achieving an appropriate selectivity profile will be more challenging. However, we did discover two novel series with selectivity for Plasmodium NMT over the other NMT orthologues in this study, and an additional two structurally distinct series with selectivity over Leishmania NMT. We believe that release of results from this study into the public domain will accelerate the discovery of NMT inhibitors to treat malaria and leishmaniasis. Our screening initiative is another example of how a tripartite partnership involving pharmaceutical industries, academic institutions and governmental/non-governmental organisations such as Medical Research Council and Wellcome Trust can stimulate research for neglected diseases. Inhibition of N-myristoyltransferase has been validated pre-clinically as a target for the treatment of fungal and trypanosome infections, using species-specific inhibitors. In order to identify inhibitors of protozoan NMTs, we chose to screen a diverse subset of the Pfizer corporate collection against Plasmodium falciparum and Leishmania donovani NMTs. Primary screening hits against either enzyme were tested for selectivity over both human NMT isoforms (HsNMT1 and HsNMT2) and for broad-spectrum anti-protozoan activity against the NMT from Trypanosoma brucei. We have identified eight series of protozoan NMT inhibitors, six having good selectivity for either Plasmodium or Leishmania NMTs over the other orthologues in this study. We believe that all of these series could form the basis of medicinal chemistry programs to deliver drug candidates against either malaria or leishmaniasis. Our screening initiative is another example of how a tripartite partnership involving pharmaceutical industries, academic institutions and governmental/non-governmental organisations such as the UK Medical Research Council and Wellcome Trust can stimulate research for neglected diseases.
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Abstract
Trypanosoma brucei is the etiological agent of devastating parasitic disease in humans and livestock in sub-saharan Africa. The pathogenicity and growth of the parasite are intimately linked to its shape and form. This is in turn derived from a highly ordered microtubule cytoskeleton that forms a tightly arrayed cage directly beneath the pellicular membrane and numerous other cytoskeletal structures such as the flagellum. The parasite undergoes extreme changes in cellular morphology during its life cycle and cell cycles which require a high level of integration and coordination of cytoskeletal processes. In this review we will discuss the role that proteomics techniques have had in advancing our understanding of the molecular composition of the cytoskeleton and its functions. We then consider future opportunities for the application of these techniques in terms of addressing some of the unanswered questions of trypanosome cytoskeletal cell biology with particular focus on the differences in the composition and organisation of the cytoskeleton through the trypanosome life-cycle.
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May SF, Peacock L, Almeida Costa CIC, Gibson WC, Tetley L, Robinson DR, Hammarton TC. The Trypanosoma brucei AIR9-like protein is cytoskeleton-associated and is required for nucleus positioning and accurate cleavage furrow placement. Mol Microbiol 2012; 84:77-92. [PMID: 22329999 PMCID: PMC3488599 DOI: 10.1111/j.1365-2958.2012.08008.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/08/2012] [Indexed: 12/26/2022]
Abstract
AIR9 is a cytoskeleton-associated protein in Arabidopsis thaliana with roles in cytokinesis and cross wall maturation, and reported homologues in land plants and excavate protists, including trypanosomatids. We show that the Trypanosoma brucei AIR9-like protein, TbAIR9, is also cytoskeleton-associated and colocalizes with the subpellicular microtubules. We find it to be expressed in all life cycle stages and show that it is essential for normal proliferation of trypanosomes in vitro. Depletion of TbAIR9 from procyclic trypanosomes resulted in increased cell length due to increased microtubule extension at the cell posterior. Additionally, the nucleus was re-positioned to a location posterior to the kinetoplast, leading to defects in cytokinesis and the generation of aberrant progeny. In contrast, in bloodstream trypanosomes, depletion of TbAIR9 had little effect on nucleus positioning, but resulted in aberrant cleavage furrow placement and the generation of non-equivalent daughter cells following cytokinesis. Our data provide insight into the control of nucleus positioning in this important pathogen and emphasize differences in the cytoskeleton and cell cycle control between two life cycle stages of the T. brucei parasite.
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Affiliation(s)
- Sophie F May
- Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of GlasgowGlasgow G12 8TA, UK
| | - Lori Peacock
- School of Clinical Veterinary Science, University of BristolLangford, Bristol BS40 7DU, UK
- School of Biological Sciences, University of BristolBristol BS8 1UG, UK
| | - Cristina I C Almeida Costa
- Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of GlasgowGlasgow G12 8TA, UK
- Instituto de Higiene e Medicina Tropical, Universidade Nova de LisboaLisbon, Portugal
| | - Wendy C Gibson
- School of Biological Sciences, University of BristolBristol BS8 1UG, UK
| | - Laurence Tetley
- School of Life Sciences, University of GlasgowGlasgow G12 8QQ, UK
| | | | - Tansy C Hammarton
- Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of GlasgowGlasgow G12 8TA, UK
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42
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Acylation-dependent and-independent membrane targeting and distinct functions of small myristoylated proteins (SMPs) in Leishmania major. Int J Parasitol 2012; 42:239-47. [DOI: 10.1016/j.ijpara.2011.12.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2011] [Revised: 12/21/2011] [Accepted: 12/22/2011] [Indexed: 11/20/2022]
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Cytokinesis in bloodstream stage Trypanosoma brucei requires a family of katanins and spastin. PLoS One 2012; 7:e30367. [PMID: 22279588 PMCID: PMC3261199 DOI: 10.1371/journal.pone.0030367] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2011] [Accepted: 12/19/2011] [Indexed: 11/19/2022] Open
Abstract
Microtubule severing enzymes regulate microtubule dynamics in a wide range of organisms and are implicated in important cell cycle processes such as mitotic spindle assembly and disassembly, chromosome movement and cytokinesis. Here we explore the function of several microtubule severing enzyme homologues, the katanins (KAT80, KAT60a, KAT60b and KAT60c), spastin (SPA) and fidgetin (FID) in the bloodstream stage of the African trypanosome parasite, Trypanosoma brucei. The trypanosome cytoskeleton is microtubule based and remains assembled throughout the cell cycle, necessitating its remodelling during cytokinesis. Using RNA interference to deplete individual proteins, we show that the trypanosome katanin and spastin homologues are non-redundant and essential for bloodstream form proliferation. Further, cell cycle analysis revealed that these proteins play essential but discrete roles in cytokinesis. The KAT60 proteins each appear to be important during the early stages of cytokinesis, while downregulation of KAT80 specifically inhibited furrow ingression and SPA depletion prevented completion of abscission. In contrast, RNA interference of FID did not result in any discernible effects. We propose that the stable microtubule cytoskeleton of T. brucei necessitates the coordinated action of a family of katanins and spastin to bring about the cytoskeletal remodelling necessary to complete cell division.
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Brand S, Cleghorn LAT, McElroy SP, Robinson DA, Smith VC, Hallyburton I, Harrison JR, Norcross NR, Spinks D, Bayliss T, Norval S, Stojanovski L, Torrie LS, Frearson JA, Brenk R, Fairlamb AH, Ferguson MAJ, Read KD, Wyatt PG, Gilbert IH. Discovery of a novel class of orally active trypanocidal N-myristoyltransferase inhibitors. J Med Chem 2011; 55:140-52. [PMID: 22148754 PMCID: PMC3256935 DOI: 10.1021/jm201091t] [Citation(s) in RCA: 91] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
N-Myristoyltransferase (NMT) represents a promising drug target for human African trypanosomiasis (HAT), which is caused by the parasitic protozoa Trypanosoma brucei. We report the optimization of a high throughput screening hit (1) to give a lead molecule DDD85646 (63), which has potent activity against the enzyme (IC(50) = 2 nM) and T. brucei (EC(50) = 2 nM) in culture. The compound has good oral pharmacokinetics and cures rodent models of peripheral HAT infection. This compound provides an excellent tool for validation of T. brucei NMT as a drug target for HAT as well as a valuable lead for further optimization.
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Affiliation(s)
- Stephen Brand
- Drug Discovery Unit, Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Sir James Black Centre, Dundee, DD1 5EH, U.K
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Galetović A, Souza RT, Santos MRM, Cordero EM, Bastos IMD, Santana JM, Ruiz JC, Lima FM, Marini MM, Mortara RA, da Silveira JF. The repetitive cytoskeletal protein H49 of Trypanosoma cruzi is a calpain-like protein located at the flagellum attachment zone. PLoS One 2011; 6:e27634. [PMID: 22096606 PMCID: PMC3214072 DOI: 10.1371/journal.pone.0027634] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2011] [Accepted: 10/20/2011] [Indexed: 12/27/2022] Open
Abstract
Background Trypanosoma cruzi has a single flagellum attached to the cell body by a network of specialized cytoskeletal and membranous connections called the flagellum attachment zone. Previously, we isolated a DNA fragment (clone H49) which encodes tandemly arranged repeats of 68 amino acids associated with a high molecular weight cytoskeletal protein. In the current study, the genomic complexity of H49 and its relationships to the T. cruzi calpain-like cysteine peptidase family, comprising active calpains and calpain-like proteins, is addressed. Immunofluorescence analysis and biochemical fractionation were used to demonstrate the cellular location of H49 proteins. Methods and Findings All of H49 repeats are associated with calpain-like sequences. Sequence analysis demonstrated that this protein, now termed H49/calpain, consists of an amino-terminal catalytic cysteine protease domain II, followed by a large region of 68-amino acid repeats tandemly arranged and a carboxy-terminal segment carrying the protease domains II and III. The H49/calpains can be classified as calpain-like proteins as the cysteine protease catalytic triad has been partially conserved in these proteins. The H49/calpains repeats share less than 60% identity with other calpain-like proteins in Leishmania and T. brucei, and there is no immunological cross reaction among them. It is suggested that the expansion of H49/calpain repeats only occurred in T. cruzi after separation of a T. cruzi ancestor from other trypanosomatid lineages. Immunofluorescence and immunoblotting experiments demonstrated that H49/calpain is located along the flagellum attachment zone adjacent to the cell body. Conclusions H49/calpain contains large central region composed of 68-amino acid repeats tandemly arranged. They can be classified as calpain-like proteins as the cysteine protease catalytic triad is partially conserved in these proteins. H49/calpains could have a structural role, namely that of ensuring that the cell body remains attached to the flagellum by connecting the subpellicular microtubule array to it.
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Affiliation(s)
- Alexandra Galetović
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, São Paulo, Brasil
- Laboratorio de Bioquímica, Departamento Biomédico, Universidad de Antofagasta, Antofagasta, Chile
| | - Renata T. Souza
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, São Paulo, Brasil
| | | | - Esteban M. Cordero
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, São Paulo, Brasil
| | - Izabela M. D. Bastos
- Departamento de Biologia Celular, Instituto de Biologia, Universidade de Brasilia, Brasilia, Brasil
| | - Jaime M. Santana
- Departamento de Biologia Celular, Instituto de Biologia, Universidade de Brasilia, Brasilia, Brasil
| | - Jeronimo C. Ruiz
- Centro de Pesquisa René Rachou (CPqRR), FIOCRUZ, Belo Horizonte, Minas Gerais, Brasil
| | - Fabio M. Lima
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, São Paulo, Brasil
| | - Marjorie M. Marini
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, São Paulo, Brasil
| | - Renato A. Mortara
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, São Paulo, Brasil
| | - José Franco da Silveira
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, São Paulo, Brasil
- * E-mail:
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Abstract
The biogenesis of the ER Exit Site/Golgi Junction (EGJ) in bloodstream-form African trypanosomes is investigated using tagged markers for ER Exit Sites, the Golgi and the bilobe structure. The typical pattern is two EGJ in G1 phase (1 kinetoplast/1 nucleus, 1K1N) through S-phase (2K1N), duplication to four EGJ in post-mitotic cells (2K2N) and segregation of two EGJ to each daughter. Lesser cell percentages have elevated EGJ copy numbers in all stages, and blocking cell cycle progression results in even higher copy numbers. EGJs are closely aligned with the flagellar attachment zone (FAZ) indicating nucleation on the FAZ-associated ER (FAZ:ER). Only the most posterior EGJ in each cell is in proximity to the bilobe, which is located at the base of the FAZ filament near the mouth of the flagellar pocket. These results indicate that EGJ replication in bloodstream trypanosomes is not tightly coupled to the cell cycle. Furthermore, segregation of EGJ is not obligately mediated by the bilobe, rather assembly of the EGJ on the FAZ:ER, which is coupled to the flagellar cytoskeleton, apparently ensures segregation with fidelity during cytokinesis. These findings differ markedly from procyclic-form trypanosomes, and models highlighting these stage-specific differences in EGJ biogenesis are proposed.
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Affiliation(s)
- James D Bangs
- Department of Medical Microbiology & Immunology, University of Wisconsin School of Medicine and Public Health, Madison, WI 53706, USA.
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Maric D, McGwire BS, Buchanan KT, Olson CL, Emmer BT, Epting CL, Engman DM. Molecular determinants of ciliary membrane localization of Trypanosoma cruzi flagellar calcium-binding protein. J Biol Chem 2011; 286:33109-17. [PMID: 21784841 DOI: 10.1074/jbc.m111.240895] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The flagellar calcium-binding protein (FCaBP) of Trypanosoma cruzi is localized to the flagellar membrane in all life cycle stages of the parasite. Myristoylation and palmitoylation of the N terminus of FCaBP are necessary for flagellar membrane targeting. Not all dually acylated proteins in T. cruzi are flagellar, however. Other determinants of FCaBP therefore likely contribute to flagellar specificity. We generated T. cruzi transfectants expressing the N-terminal 24 or 12 amino acids of FCaBP fused to GFP. Analysis of these mutants revealed that although amino acids 1-12 are sufficient for dual acylation and membrane binding, amino acids 13-24 are required for flagellar specificity and lipid raft association. Mutagenesis of several conserved lysine residues in the latter peptide demonstrated that these residues are essential for flagellar targeting and lipid raft association. Finally, FCaBP was expressed in the protozoan Leishmania amazonensis, which lacks FCaBP. The flagellar localization and membrane association of FCaBP in L. amazonensis suggest that the mechanisms for flagellar targeting, including a specific palmitoyl acyltransferase, are conserved in this organism.
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Affiliation(s)
- Danijela Maric
- Department of Pathology, Northwestern University, Chicago, Illinois 60611, USA
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48
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Ennes-Vidal V, Menna-Barreto RFS, Santos ALS, Branquinha MH, d'Avila-Levy CM. MDL28170, a calpain inhibitor, affects Trypanosoma cruzi metacyclogenesis, ultrastructure and attachment to Rhodnius prolixus midgut. PLoS One 2011; 6:e18371. [PMID: 21483751 PMCID: PMC3070728 DOI: 10.1371/journal.pone.0018371] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2010] [Accepted: 03/06/2011] [Indexed: 11/18/2022] Open
Abstract
Background Trypanosoma cruzi is the etiological agent of Chagas' disease. During the parasite life cycle, many molecules are involved in the differentiation process and infectivity. Peptidases are relevant for crucial steps of T. cruzi life cycle; as such, it is conceivable that they may participate in the metacyclogenesis and interaction with the invertebrate host. Methodology/Principal Findings In this paper, we have investigated the effect of the calpain inhibitor MDL28170 on the attachment of T. cruzi epimastigotes to the luminal midgut surface of Rhodnius prolixus, as well as on the metacyclogenesis process and ultrastructure. MDL28170 treatment was capable of significantly reducing the number of bound epimastigotes to the luminal surface midgut of the insect. Once the cross-reactivity of the anti-Dm-calpain was assessed, it was possible to block calpain molecules by the antibody, leading to a significant reduction in the capacity of adhesion to the insect guts by T. cruzi. However, the antibodies were unable to interfere in metacyclogenesis, which was impaired by the calpain inhibitor presenting a significant reduction in the number of metacyclic trypomastigotes. The calpain inhibitor also promoted a direct effect against bloodstream trypomastigotes. Ultrastructural analysis of epimastigotes treated with the calpain inhibitor revealed disorganization in the reservosomes, Golgi and plasma membrane disruption. Conclusions/Significance The presence of calpain and calpain-like molecules in a wide range of organisms suggests that these proteins could be necessary for basic cellular functions. Herein, we demonstrated the effects of MDL28170 in crucial steps of the T. cruzi life cycle, such as attachment to the insect midgut and metacyclogenesis, as well as in parasite viability and morphology. Together with our previous findings, these results help to shed some light on the functions of T. cruzi calpains. Considering the potential roles of these molecules on the interaction with both invertebrate and vertebrate hosts, it is interesting to improve knowledge on these molecules in T. cruzi.
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Affiliation(s)
- Vítor Ennes-Vidal
- Laboratório de Biologia Molecular e Doenças Endêmicas, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz (Fiocruz), Rio de Janeiro, Brazil
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49
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Sorimachi H, Hata S, Ono Y. Expanding members and roles of the calpain superfamily and their genetically modified animals. Exp Anim 2011; 59:549-66. [PMID: 21030783 DOI: 10.1538/expanim.59.549] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Calpains are intracellular Ca²(+)-dependent cysteine proteases (Clan CA, family C02, EC 3.4.22.17) found in almost all eukaryotes and some bacteria. Calpains display limited proteolytic activity at neutral pH, proteolysing substrates to transform and modulate their structures and activities, and are therefore called "modulator proteases". The human genome has 15 genes that encode a calpain-like protease domain, generating diverse calpain homologues that possess combinations of several functional domains such as Ca²(+)-binding domains and Zn-finger domains. The importance of the physiological roles of calpains is reflected in the fact that particular defects in calpain functionality cause a variety of deficiencies in many different organisms, including lethality, muscular dystrophies, lissencephaly, and tumorigenesis. In this review, the unique characteristics of this distinctive protease superfamily are introduced in terms of genetically modified animals, some of which are animal models of calpain deficiency diseases.
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Affiliation(s)
- Hiroyuki Sorimachi
- Calpain Project, The Tokyo Metropolitan Institute of Medical Science (Rinshoken), Japan
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Sorimachi H, Hata S, Ono Y. Calpain chronicle--an enzyme family under multidisciplinary characterization. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2011; 87:287-327. [PMID: 21670566 PMCID: PMC3153876 DOI: 10.2183/pjab.87.287] [Citation(s) in RCA: 112] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2011] [Accepted: 03/04/2011] [Indexed: 05/29/2023]
Abstract
Calpain is an intracellular Ca2+-dependent cysteine protease (EC 3.4.22.17; Clan CA, family C02) discovered in 1964. It was also called CANP (Ca2+-activated neutral protease) as well as CASF, CDP, KAF, etc. until 1990. Calpains are found in almost all eukaryotes and a few bacteria, but not in archaebacteria. Calpains have a limited proteolytic activity, and function to transform or modulate their substrates' structures and activities; they are therefore called, "modulator proteases." In the human genome, 15 genes--CAPN1, CAPN2, etc.--encode a calpain-like protease domain. Their products are calpain homologs with divergent structures and various combinations of functional domains, including Ca2+-binding and microtubule-interaction domains. Genetic studies have linked calpain deficiencies to a variety of defects in many different organisms, including lethality, muscular dystrophies, gastropathy, and diabetes. This review of the study of calpains focuses especially on recent findings about their structure-function relationships. These discoveries have been greatly aided by the development of 3D structural studies and genetic models.
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Affiliation(s)
- Hiroyuki Sorimachi
- Calpain Project, Department of Advanced Science for Biomolecules, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan.
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