1
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Howell J, Omwenga S, Jimenez M, Hammarton TC. Analysis of the Leishmania mexicana promastigote cell cycle using imaging flow cytometry provides new insights into cell cycle flexibility and events of short duration. PLoS One 2024; 19:e0311367. [PMID: 39361666 PMCID: PMC11449296 DOI: 10.1371/journal.pone.0311367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2024] [Accepted: 09/17/2024] [Indexed: 10/05/2024] Open
Abstract
Promastigote Leishmania mexicana have a complex cell division cycle characterised by the ordered replication of several single-copy organelles, a prolonged S phase and rapid G2 and cytokinesis phases, accompanied by cell cycle stage-associated morphological changes. Here we exploit these morphological changes to develop a high-throughput and semi-automated imaging flow cytometry (IFC) pipeline to analyse the cell cycle in live L. mexicana. Firstly, we demonstrate that, unlike several other DNA stains, Vybrant™ DyeCycle™ Orange (DCO) is non-toxic and enables quantitative DNA imaging in live promastigotes. Secondly, by tagging the orphan spindle kinesin, KINF, with mNeonGreen, we describe KINF's cell cycle-dependent expression and localisation. Then, by combining manual gating of DCO DNA intensity profiles with automated masking and morphological measurements of parasite images, visual determination of the number of flagella per cell, and automated masking and analysis of mNG:KINF fluorescence, we provide a newly detailed description of L. mexicana promastigote cell cycle events that, for the first time, includes the durations of individual G2, mitosis and post-mitosis phases, and identifies G1 cells within the first 12 minutes of the new cell cycle. Our custom-developed masking and gating scheme allowed us to identify elusive G2 cells and to demonstrate that the CDK-inhibitor, flavopiridol, arrests cells in G2 phase, rather than mitosis, providing proof-of-principle of the utility of IFC for drug mechanism-of-action studies. Further, the high-throughput nature of IFC allowed the close examination of promastigote cytokinesis, revealing considerable flexibility in both the timing of cytokinesis initiation and the direction of furrowing, in contrast to the related kinetoplastid parasite, Trypanosoma brucei and many other cell types. Our new pipeline offers many advantages over traditional methods of cell cycle analysis such as fluorescence microscopy and flow cytometry and paves the way for novel high-throughput analysis of Leishmania cell division.
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Affiliation(s)
- Jessie Howell
- James Watt School of Engineering, University of Glasgow, Glasgow, United Kingdom
| | - Sulochana Omwenga
- School of Infection and Immunity, University of Glasgow, Glasgow, United Kingdom
| | - Melanie Jimenez
- Biomedical Engineering Department, University of Strathclyde, Glasgow, United Kingdom
| | - Tansy C. Hammarton
- School of Infection and Immunity, University of Glasgow, Glasgow, United Kingdom
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2
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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: 0] [Impact Index Per Article: 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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3
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Aellig S, Billington K, Damasceno JD, Davidson L, Dobramysl U, Etzensperger R, Ferreira ER, Gluenz E, Mottram JC, Neish R, Pereira R, Smith J, Sunter JD, Volf P, Wheeler RJ, Young M. LeishGEM: genome-wide deletion mutant fitness and protein localisations in Leishmania. Trends Parasitol 2024; 40:675-678. [PMID: 39030136 DOI: 10.1016/j.pt.2024.06.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2024] [Revised: 06/03/2024] [Accepted: 06/03/2024] [Indexed: 07/21/2024]
Abstract
LeishGEM is a genome-wide functional annotation community resource for Leishmania mexicana, where deletion mutant growth in vitro and in vivo is measured and protein localisation is determined by endogenous tagging and LOPIT-DC (localisation of organelle proteins by isotope tagging with differential centrifugation) spatial proteomics. Data are being made available pre-publication via http://leishgem.org which allows data-driven identification of the mechanisms for Leishmania parasitism.
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4
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Azevedo LG, Sosa E, de Queiroz ATL, Barral A, Wheeler RJ, Nicolás MF, Farias LP, Do Porto DF, Ramos PIP. High-throughput prioritization of target proteins for development of new antileishmanial compounds. Int J Parasitol Drugs Drug Resist 2024; 25:100538. [PMID: 38669848 PMCID: PMC11068527 DOI: 10.1016/j.ijpddr.2024.100538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 03/11/2024] [Accepted: 04/04/2024] [Indexed: 04/28/2024]
Abstract
Leishmaniasis, a vector-borne disease, is caused by the infection of Leishmania spp., obligate intracellular protozoan parasites. Presently, human vaccines are unavailable, and the primary treatment relies heavily on systemic drugs, often presenting with suboptimal formulations and substantial toxicity, making new drugs a high priority for LMIC countries burdened by the disease, but a low priority in the agenda of most pharmaceutical companies due to unattractive profit margins. New ways to accelerate the discovery of new, or the repositioning of existing drugs, are needed. To address this challenge, our study aimed to identify potential protein targets shared among clinically-relevant Leishmania species. We employed a subtractive proteomics and comparative genomics approach, integrating high-throughput multi-omics data to classify these targets based on different druggability metrics. This effort resulted in the ranking of 6502 ortholog groups of protein targets across 14 pathogenic Leishmania species. Among the top 20 highly ranked groups, metabolic processes known to be attractive drug targets, including the ubiquitination pathway, aminoacyl-tRNA synthetases, and purine synthesis, were rediscovered. Additionally, we unveiled novel promising targets such as the nicotinate phosphoribosyltransferase enzyme and dihydrolipoamide succinyltransferases. These groups exhibited appealing druggability features, including less than 40% sequence identity to the human host proteome, predicted essentiality, structural classification as highly druggable or druggable, and expression levels above the 50th percentile in the amastigote form. The resources presented in this work also represent a comprehensive collection of integrated data regarding trypanosomatid biology.
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Affiliation(s)
- Lucas G Azevedo
- Center for Data and Knowledge Integration for Health (CIDACS), Instituto Gonçalo Moniz, Fundação Oswaldo Cruz (Fiocruz Bahia), Salvador, Bahia, Brazil; Post-graduate Program in Biotechnology and Investigative Medicine, Instituto Gonçalo Moniz, Salvador, Bahia, Brazil.
| | - Ezequiel Sosa
- Universidad de Buenos Aires, Buenos Aires, Argentina.
| | - Artur T L de Queiroz
- Center for Data and Knowledge Integration for Health (CIDACS), Instituto Gonçalo Moniz, Fundação Oswaldo Cruz (Fiocruz Bahia), Salvador, Bahia, Brazil; Post-graduate Program in Biotechnology and Investigative Medicine, Instituto Gonçalo Moniz, Salvador, Bahia, Brazil.
| | - Aldina Barral
- Laboratório de Medicina e Saúde Pública de Precisão (MeSP2), Instituto Gonçalo Moniz, Fundação Oswaldo Cruz (Fiocruz Bahia), Salvador, Bahia, Brazil.
| | - Richard J Wheeler
- Peter Medawar Building for Pathogen Research, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom.
| | - Marisa F Nicolás
- Laboratório Nacional de Computação Científica, Petrópolis, Rio de Janeiro, Brazil.
| | - Leonardo P Farias
- Post-graduate Program in Biotechnology and Investigative Medicine, Instituto Gonçalo Moniz, Salvador, Bahia, Brazil; Laboratório de Medicina e Saúde Pública de Precisão (MeSP2), Instituto Gonçalo Moniz, Fundação Oswaldo Cruz (Fiocruz Bahia), Salvador, Bahia, Brazil.
| | | | - Pablo Ivan P Ramos
- Center for Data and Knowledge Integration for Health (CIDACS), Instituto Gonçalo Moniz, Fundação Oswaldo Cruz (Fiocruz Bahia), Salvador, Bahia, Brazil; Post-graduate Program in Biotechnology and Investigative Medicine, Instituto Gonçalo Moniz, Salvador, Bahia, Brazil.
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5
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Bieber BV, Lockett SG, Glasser SK, St Clair FA, Portillo NO, Adler LS, Povelones ML. Genetic modification of the bee parasite Crithidia bombi for improved visualization and protein localization. Exp Parasitol 2024; 262:108789. [PMID: 38762201 DOI: 10.1016/j.exppara.2024.108789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Revised: 05/02/2024] [Accepted: 05/15/2024] [Indexed: 05/20/2024]
Abstract
Crithidia bombi is a trypanosomatid parasite that infects several species of bumble bees (Bombus spp.), by adhering to their intestinal tract. Crithidia bombi infection impairs learning and reduces survival of workers and the fitness of overwintering queens. Although there is extensive research on the ecology of this host-pathogen system, we understand far less about the mechanisms that mediate internal infection dynamics. Crithidia bombi infects hosts by attaching to the hindgut via the flagellum, and one previous study found that a nectar secondary compound removed the flagellum, preventing attachment. However, approaches that allow more detailed observation of parasite attachment and growth would allow us to better understand factors mediating this host-pathogen relationship. We established techniques for genetic manipulation and visualization of cultured C. bombi. Using constructs established for Crithidia fasciculata, we successfully generated C. bombi cells expressing ectopic fluorescent transgenes using two different selectable markers. To our knowledge, this is the first genetic modification of this species. We also introduced constructs that label the mitochondrion and nucleus of the parasite, showing that subcellular targeting signals can function across parasite species to highlight specific organelles. Finally, we visualized fluorescently tagged parasites in vitro in both their swimming and attached forms, and in vivo in bumble bee (Bombus impatiens) hosts. Expanding our cell and molecular toolkit for C. bombi will help us better understand how factors such as host diet, immune system, and physiology mediate outcomes of infection by these common parasites.
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Affiliation(s)
| | - Sarah G Lockett
- Department of Biology, Villanova University, Villanova, PA, 19085, USA
| | - Sonja K Glasser
- Department of Biology, University of Massachusetts Amherst, Amherst, MA, 01003, USA
| | - Faith A St Clair
- Department of Biology, Villanova University, Villanova, PA, 19085, USA
| | - Neida O Portillo
- Department of Biology, University of Massachusetts Amherst, Amherst, MA, 01003, USA
| | - Lynn S Adler
- Department of Biology, University of Massachusetts Amherst, Amherst, MA, 01003, USA
| | - Megan L Povelones
- Department of Biology, Villanova University, Villanova, PA, 19085, USA.
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6
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Ribeiro JM, Silva PA, Costa-Silva HM, Santi AMM, Murta SMF. Deletion of the lipid droplet protein kinase gene affects lipid droplets biogenesis, parasite infectivity, and resistance to trivalent antimony in Leishmania infantum. PLoS Negl Trop Dis 2024; 18:e0011880. [PMID: 38236929 PMCID: PMC10795987 DOI: 10.1371/journal.pntd.0011880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2023] [Accepted: 12/21/2023] [Indexed: 01/22/2024] Open
Abstract
The Lipid Droplet Protein Kinase (LDK) facilitates lipid droplet (LD) biogenesis, organelles involved in various metabolic and signaling functions in trypanosomatids. As LDK's function has not been previously explored in Leishmania spp., we utilized CRISPR/Cas9 technology to generate LDK-knockout lines of Leishmania infantum to investigate its role in this parasite. Our findings demonstrate that LDK is not an essential gene for L. infantum, as its deletion did not impede parasite survival. Furthermore, removing LDK did not impact the growth of promastigote forms of L. infantum lacking LDK. However, a noticeable reduction in LDs occurred during the stationary phase of parasite growth following LDK deletion. In the presence of myriocin, a LD inducer, LDK-knockout parasites displayed reduced LD abundance during both logarithmic and stationary growth phases compared to control parasites. Moreover, an infection analysis involving THP-1 cells revealed that 72 h post-infection, LDK-knockout L. infantum lines exhibited fewer infected macrophages and intracellular amastigotes than control parasites. LDK-knockout L. infantum lines also displayed 1.7 to 1.8 -fold greater resistance to trivalent antimony than control parasites. There were no observed alterations in susceptibility to amphotericin B, miltefosine, or menadione in LDK-knockout L. infantum lines. Our results suggest that LDK plays a crucial role in the biogenesis and/or maintenance of LDs in L. infantum, as well as in parasite infectivity and resistance to trivalent antimony.
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Affiliation(s)
- Juliana Martins Ribeiro
- Grupo Genômica Funcional de Parasitos, Instituto René Rachou, Fiocruz Minas, Belo Horizonte, Minas Gerais, Brazil
| | - Paula Alves Silva
- Grupo Genômica Funcional de Parasitos, Instituto René Rachou, Fiocruz Minas, Belo Horizonte, Minas Gerais, Brazil
| | - Héllida Marina Costa-Silva
- Grupo Genômica Funcional de Parasitos, Instituto René Rachou, Fiocruz Minas, Belo Horizonte, Minas Gerais, Brazil
| | - Ana Maria Murta Santi
- Grupo Genômica Funcional de Parasitos, Instituto René Rachou, Fiocruz Minas, Belo Horizonte, Minas Gerais, Brazil
| | - Silvane Maria Fonseca Murta
- Grupo Genômica Funcional de Parasitos, Instituto René Rachou, Fiocruz Minas, Belo Horizonte, Minas Gerais, Brazil
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7
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Campbell PC, de Graffenried CL. Morphogenesis in Trypanosoma cruzi epimastigotes proceeds via a highly asymmetric cell division. PLoS Negl Trop Dis 2023; 17:e0011731. [PMID: 37917723 PMCID: PMC10656021 DOI: 10.1371/journal.pntd.0011731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 11/17/2023] [Accepted: 10/16/2023] [Indexed: 11/04/2023] Open
Abstract
Trypanosoma cruzi is a protist parasite that is the causative agent of Chagas disease, a neglected tropical disease endemic to the Americas. T. cruzi cells are highly polarized and undergo morphological changes as they cycle within their insect and mammalian hosts. Work on related trypanosomatids has described cell division mechanisms in several life-cycle stages and identified a set of essential morphogenic proteins that serve as markers for key events during trypanosomatid division. Here, we use Cas9-based tagging of morphogenic genes, live-cell imaging, and expansion microscopy to study the cell division mechanism of the insect-resident epimastigote form of T. cruzi, which represents an understudied trypanosomatid morphotype. We find that T. cruzi epimastigote cell division is highly asymmetric, producing one daughter cell that is significantly smaller than the other. Daughter cell division rates differ by 4.9 h, which may be a consequence of this size disparity. Many of the morphogenic proteins identified in T. brucei have altered localization patterns in T. cruzi epimastigotes, which may reflect fundamental differences in the cell division mechanism of this life cycle stage, which widens and shortens the cell body to accommodate the duplicated organelles and cleavage furrow rather than elongating the cell body along the long axis of the cell, as is the case in life-cycle stages that have been studied in T. brucei. This work provides a foundation for further investigations of T. cruzi cell division and shows that subtle differences in trypanosomatid cell morphology can alter how these parasites divide.
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Affiliation(s)
- Paul C. Campbell
- Department of Molecular Microbiology and Immunology, Brown University, Providence, Rhode Island, United States of America
| | - Christopher L. de Graffenried
- Department of Molecular Microbiology and Immunology, Brown University, Providence, Rhode Island, United States of America
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8
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Schichler D, Konle A, Spath EM, Riegler S, Klein A, Seleznev A, Jung S, Wuppermann T, Wetterich N, Borges A, Meyer-Natus E, Havlicek K, Pérez Cabrera S, Niedermüller K, Sajko S, Dohn M, Malzer X, Riemer E, Tumurbaatar T, Djinovic-Carugo K, Dong G, Janzen CJ, Morriswood B. Characterisation of TbSmee1 suggests endocytosis allows surface-bound cargo to enter the trypanosome flagellar pocket. J Cell Sci 2023; 136:jcs261548. [PMID: 37737012 PMCID: PMC10652038 DOI: 10.1242/jcs.261548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Accepted: 08/11/2023] [Indexed: 09/23/2023] Open
Abstract
All endocytosis and exocytosis in the African trypanosome Trypanosoma brucei occurs at a single subdomain of the plasma membrane. This subdomain, the flagellar pocket, is a small vase-shaped invagination containing the root of the single flagellum of the cell. Several cytoskeleton-associated multiprotein complexes are coiled around the neck of the flagellar pocket on its cytoplasmic face. One of these, the hook complex, was proposed to affect macromolecule entry into the flagellar pocket lumen. In previous work, knockdown of T. brucei (Tb)MORN1, a hook complex component, resulted in larger cargo being unable to enter the flagellar pocket. In this study, the hook complex component TbSmee1 was characterised in bloodstream form T. brucei and found to be essential for cell viability. TbSmee1 knockdown resulted in flagellar pocket enlargement and impaired access to the flagellar pocket membrane by surface-bound cargo, similar to depletion of TbMORN1. Unexpectedly, inhibition of endocytosis by knockdown of clathrin phenocopied TbSmee1 knockdown, suggesting that endocytic activity itself is a prerequisite for the entry of surface-bound cargo into the flagellar pocket.
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Affiliation(s)
- Daja Schichler
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, 97074 Würzburg, Germany
| | - Antonia Konle
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, 97074 Würzburg, Germany
| | - Eva-Maria Spath
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, 97074 Würzburg, Germany
| | - Sina Riegler
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, 97074 Würzburg, Germany
| | - Alexandra Klein
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, 97074 Würzburg, Germany
| | - Anna Seleznev
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, 97074 Würzburg, Germany
| | - Sisco Jung
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, 97074 Würzburg, Germany
| | - Timothy Wuppermann
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, 97074 Würzburg, Germany
| | - Noah Wetterich
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, 97074 Würzburg, Germany
| | - Alyssa Borges
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, 97074 Würzburg, Germany
| | - Elisabeth Meyer-Natus
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, 97074 Würzburg, Germany
| | - Katharina Havlicek
- Department of Biochemistry and Cell Biology, Max Perutz Labs, University of Vienna, Vienna Biocenter (VBC), 1030 Vienna, Austria
| | | | - Korbinian Niedermüller
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, 97074 Würzburg, Germany
| | - Sara Sajko
- Department of Structural and Computational Biology, Max Perutz Labs, University of Vienna, Vienna Biocenter (VBC), 1030 Vienna, Austria
| | - Maximilian Dohn
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, 97074 Würzburg, Germany
| | - Xenia Malzer
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, 97074 Würzburg, Germany
| | - Emily Riemer
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, 97074 Würzburg, Germany
| | - Tuguldur Tumurbaatar
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, 97074 Würzburg, Germany
| | - Kristina Djinovic-Carugo
- Department of Structural and Computational Biology, Max Perutz Labs, University of Vienna, Vienna Biocenter (VBC), 1030 Vienna, Austria
- Department of Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, 1000 Ljubljana, Slovenia
- European Molecular Biology Laboratory (EMBL) Grenoble, 38000 Grenoble, France
| | - Gang Dong
- Center for Medical Biochemistry, Max Perutz Labs, Medical University of Vienna, Vienna Biocenter (VBC), 1030 Vienna, Austria
| | - Christian J. Janzen
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, 97074 Würzburg, Germany
| | - Brooke Morriswood
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, 97074 Würzburg, Germany
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9
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Pyrih J, Hammond M, Alves A, Dean S, Sunter JD, Wheeler RJ, Gull K, Lukeš J. Comprehensive sub-mitochondrial protein map of the parasitic protist Trypanosoma brucei defines critical features of organellar biology. Cell Rep 2023; 42:113083. [PMID: 37669165 DOI: 10.1016/j.celrep.2023.113083] [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: 03/19/2023] [Revised: 06/30/2023] [Accepted: 08/17/2023] [Indexed: 09/07/2023] Open
Abstract
We have generated a high-confidence mitochondrial proteome (MitoTag) of the Trypanosoma brucei procyclic stage containing 1,239 proteins. For 337 of these, a mitochondrial localization had not been described before. We use the TrypTag dataset as a foundation and take advantage of the properties of the fluorescent protein tag that causes aberrant but fortuitous accumulation of tagged matrix and inner membrane proteins near the kinetoplast (mitochondrial DNA). Combined with transmembrane domain predictions, this characteristic allowed categorization of 1,053 proteins into mitochondrial sub-compartments, the detection of unique matrix-localized fucose and methionine synthesis, and the identification of new kinetoplast proteins, which showed kinetoplast-linked pyrimidine synthesis. Moreover, disruption of targeting signals by tagging allowed mapping of the mode of protein targeting to these sub-compartments, identifying a set of C-tail anchored outer mitochondrial membrane proteins and mitochondrial carriers likely employing multiple target peptides. This dataset represents a comprehensive, updated mapping of the mitochondrion.
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Affiliation(s)
- Jan Pyrih
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic; Department of Biochemistry, University of Cambridge, Cambridge, UK; Faculty of Science, University of Ostrava, Ostrava, Czech Republic.
| | - Michael Hammond
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
| | | | - Samuel Dean
- Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, UK
| | | | - Richard John Wheeler
- Peter Medawar Building for Pathogen Research, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Keith Gull
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Julius Lukeš
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic; Faculty of Sciences, University of South Bohemia, České Budějovice (Budweis), Czech Republic.
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10
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Campbell PC, de Graffenried CL. Morphogenesis in Trypanosoma cruzi epimastigotes proceeds via a highly asymmetric cell division. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.24.542100. [PMID: 37293088 PMCID: PMC10245916 DOI: 10.1101/2023.05.24.542100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Trypanosoma cruzi is a protist parasite that is the causative agent of Chagas' disease, a neglected tropical disease endemic to the Americas. T. cruzi cells are highly polarized and undergo morphological changes as they cycle within their insect and mammalian hosts. Work on related trypanosomatids has described cell division mechanisms in several life-cycle stages and identified a set of essential morphogenic proteins that serve as markers for key events during trypanosomatid division. Here, we use Cas9-based tagging of morphogenic genes, live-cell imaging, and expansion microscopy to study the cell division mechanism of the insect-resident epimastigote form of T. cruzi, which represents an understudied trypanosomatid morphotype. We find that T. cruzi epimastigote cell division is highly asymmetric, producing one daughter cell that is significantly smaller than the other. Daughter cell division rates differ by 4.9 h, which may be a consequence of this size disparity. Many of the morphogenic proteins identified in T. brucei have altered localization patterns in T. cruzi epimastigoes, which may reflect fundamental differences in the cell division mechanism of this life cycle stage, which widens and shortens the cell body to accommodate the duplicated organelles and cleavage furrow rather than elongating the cell body along the long axis of the cell, as is the case in life-cycle stages that have been studied in T. brucei. This work provides a foundation for further investigations of T. cruzi cell division and shows that subtle differences in trypansomatid cell morphology can alter how these parasites divide.
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Affiliation(s)
- Paul C. Campbell
- Department of Molecular Microbiology and Immunology, Brown University, Providence, Rhode Island, USA
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11
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Sunter JD, Dean S, Wheeler RJ. TrypTag.org: from images to discoveries using genome-wide protein localisation in Trypanosoma brucei. Trends Parasitol 2023; 39:328-331. [PMID: 36925446 DOI: 10.1016/j.pt.2023.02.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 02/19/2023] [Accepted: 02/19/2023] [Indexed: 03/18/2023]
Abstract
TrypTag was a 4-year project to tag the N- and C-termini of almost all Trypanosoma brucei proteins with a fluorescent protein and record the subcellular localisation through images and manual annotation. We highlight the new routes to cell biological discovery this transformative resource is enabling for parasitologists and cell biologists.
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Affiliation(s)
- Jack D Sunter
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, UK.
| | - Samuel Dean
- Warwick Medical School, University of Warwick, Coventry, UK.
| | - Richard John Wheeler
- Peter Medawar Building for Pathogen Research, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
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12
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Moreira POL, Nogueira PM, Monte-Neto RL. Next-Generation Leishmanization: Revisiting Molecular Targets for Selecting Genetically Engineered Live-Attenuated Leishmania. Microorganisms 2023; 11:microorganisms11041043. [PMID: 37110466 PMCID: PMC10145799 DOI: 10.3390/microorganisms11041043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Revised: 04/07/2023] [Accepted: 04/14/2023] [Indexed: 04/29/2023] Open
Abstract
Despite decades of research devoted to finding a vaccine against leishmaniasis, we are still lacking a safe and effective vaccine for humans. Given this scenario, the search for a new prophylaxis alternative for controlling leishmaniasis should be a global priority. Inspired by leishmanization-a first generation vaccine strategy where live L. major parasites are inoculated in the skin to protect against reinfection-live-attenuated Leishmania vaccine candidates are promising alternatives due to their robust elicited protective immune response. In addition, they do not cause disease and could provide long-term protection upon challenge with a virulent strain. The discovery of a precise and easy way to perform CRISPR/Cas-based gene editing allowed the selection of safer null mutant live-attenuated Leishmania parasites obtained by gene disruption. Here, we revisited molecular targets associated with the selection of live-attenuated vaccinal strains, discussing their function, their limiting factors and the ideal candidate for the next generation of genetically engineered live-attenuated Leishmania vaccines to control leishmaniasis.
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Affiliation(s)
- Paulo O L Moreira
- Biotechnology Applied to Pathogens (BAP), Instituto René Rachou, Fundação Oswaldo Cruz, Fiocruz Minas, Belo Horizonte 30190-009, Brazil
| | - Paula M Nogueira
- Biotechnology Applied to Pathogens (BAP), Instituto René Rachou, Fundação Oswaldo Cruz, Fiocruz Minas, Belo Horizonte 30190-009, Brazil
| | - Rubens L Monte-Neto
- Biotechnology Applied to Pathogens (BAP), Instituto René Rachou, Fundação Oswaldo Cruz, Fiocruz Minas, Belo Horizonte 30190-009, Brazil
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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: 45] [Impact Index Per Article: 45.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [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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14
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Pseudokinase NRP1 facilitates endocytosis of transferrin in the African trypanosome. Sci Rep 2022; 12:18572. [PMID: 36329148 PMCID: PMC9633767 DOI: 10.1038/s41598-022-22054-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Accepted: 10/10/2022] [Indexed: 11/06/2022] Open
Abstract
Trypanosoma brucei causes human African trypanosomiasis (HAT) and nagana in cattle. During infection of a vertebrate, endocytosis of host transferrin (Tf) is important for viability of the parasite. The majority of proteins involved in trypanosome endocytosis of Tf are unknown. Here we identify pseudokinase NRP1 (Tb427tmp.160.4770) as a regulator of Tf endocytosis. Genetic knockdown of NRP1 inhibited endocytosis of Tf without blocking uptake of bovine serum albumin. Binding of Tf to the flagellar pocket was not affected by knockdown of NRP1. However the quantity of Tf per endosome dropped significantly, consistent with NRP1 promoting robust capture and/or retention of Tf in vesicles. NRP1 is involved in motility of Tf-laden vesicles since distances between endosomes and the kinetoplast were reduced after knockdown of the gene. In search of possible mediators of NRP1 modulation of Tf endocytosis, the gene was knocked down and the phosphoproteome analyzed. Phosphorylation of protein kinases forkhead, NEK6, and MAPK10 was altered, in addition to EpsinR, synaptobrevin and other vesicle-associated proteins predicted to be involved in endocytosis. These candidate proteins may link NRP1 functionally either to protein kinases or to vesicle-associated proteins.
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15
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Genome-scale RNA interference profiling of Trypanosoma brucei cell cycle progression defects. Nat Commun 2022; 13:5326. [PMID: 36088375 PMCID: PMC9464253 DOI: 10.1038/s41467-022-33109-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 08/31/2022] [Indexed: 11/21/2022] Open
Abstract
Trypanosomatids, which include major pathogens of humans and livestock, are flagellated protozoa for which cell cycle controls and the underlying mechanisms are not completely understood. Here, we describe a genome-wide RNA-interference library screen for cell cycle defects in Trypanosoma brucei. We induced massive parallel knockdown, sorted the perturbed population using high-throughput flow cytometry, deep-sequenced RNAi-targets from each stage and digitally reconstructed cell cycle profiles at a genomic scale; also enabling data visualisation using an online tool ( https://tryp-cycle.pages.dev/ ). Analysis of several hundred genes that impact cell cycle progression reveals >100 flagellar component knockdowns linked to genome endoreduplication, evidence for metabolic control of the G1-S transition, surface antigen regulatory mRNA-binding protein knockdowns linked to G2M accumulation, and a putative nucleoredoxin required for both mitochondrial genome segregation and for mitosis. The outputs provide comprehensive functional genomic evidence for the known and novel machineries, pathways and regulators that coordinate trypanosome cell cycle progression.
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Boy RL, Hong A, Aoki JI, Floeter-Winter LM, Laranjeira-Silva MF. Reporter gene systems: a powerful tool for Leishmania studies. CURRENT RESEARCH IN MICROBIAL SCIENCES 2022; 3:100165. [DOI: 10.1016/j.crmicr.2022.100165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022] Open
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Orahoske CM, Afrin M, Li Y, Hanna J, Marbury M, Li B, Su B. Identification of Prazosin as a Potential Flagellum Attachment Zone 1(FAZ1) Inhibitor for the Treatment of Human African Trypanosomiasis. ACS Infect Dis 2022; 8:1711-1726. [PMID: 35894227 DOI: 10.1021/acsinfecdis.2c00331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Human African trypanosomiasis (HAT) remains a health threat to sub-Saharan Africa. The current treatments suffer from drug resistance and life-threatening side effects, making drug discovery for HAT still important. A high-throughput screening of the library of pharmaceutically active compounds identified prazosin, an α-adrenoceptor antagonist, that showed selective activity toward Trypanosoma brucei brucei. Furthermore, a series of prazosin analogues were examined, and overall, the new analogues had improved activity and selectivity. To elucidate the binding partner, a biotin-conjugated probe was synthesized, and a protein pulldown assay combined with a proteomic analysis identified the flagellum attachment zone 1 (FAZ1) filament as an interacting partner. Additionally, prazosin treatment resulted in dysfunction of the flagellum of trypanosome cells, which is indicative of a FAZ1 irregularity. We also examined the drug distribution by utilizing immunofluorescence with a designed fluorescent analogue that showed partial colocalization with FAZ1. With the activity of the prazosin analogues, a structure-activity relationship (SAR) was summarized for future lead optimization. Our findings provide a new group of FAZ1 inhibitors as novel antitrypanosomal agents.
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Affiliation(s)
- Cody M Orahoske
- Department of Chemistry, Center for Gene Regulation in Health and Disease, College of Sciences & Health Professions, Cleveland State University, 2121 Euclid Ave., Cleveland, Ohio 44115, United States
| | - Marjia Afrin
- Department of Biological, Geological, and Environmental Sciences, Center for Gene Regulation in Health and Disease, College of Sciences and Health Professions, Cleveland State University, 2121 Euclid Ave., Cleveland, Ohio 44115, United States
| | - Yaxin Li
- Department of Chemistry, Center for Gene Regulation in Health and Disease, College of Sciences & Health Professions, Cleveland State University, 2121 Euclid Ave., Cleveland, Ohio 44115, United States
| | - Jovana Hanna
- Department of Chemistry, Center for Gene Regulation in Health and Disease, College of Sciences & Health Professions, Cleveland State University, 2121 Euclid Ave., Cleveland, Ohio 44115, United States
| | - Myah Marbury
- Department of Chemistry, Center for Gene Regulation in Health and Disease, College of Sciences & Health Professions, Cleveland State University, 2121 Euclid Ave., Cleveland, Ohio 44115, United States
| | - Bibo Li
- Department of Biological, Geological, and Environmental Sciences, Center for Gene Regulation in Health and Disease, College of Sciences and Health Professions, Cleveland State University, 2121 Euclid Ave., Cleveland, Ohio 44115, United States
| | - Bin Su
- Department of Chemistry, Center for Gene Regulation in Health and Disease, College of Sciences & Health Professions, Cleveland State University, 2121 Euclid Ave., Cleveland, Ohio 44115, United States
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18
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López-Escobar L, Hänisch B, Halliday C, Ishii M, Akiyoshi B, Dean S, Sunter JD, Wheeler RJ, Gull K. Stage-specific transcription activator ESB1 regulates monoallelic antigen expression in Trypanosoma brucei. Nat Microbiol 2022; 7:1280-1290. [PMID: 35879525 PMCID: PMC9352583 DOI: 10.1038/s41564-022-01175-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 06/14/2022] [Indexed: 11/09/2022]
Abstract
Variant surface glycoprotein (VSG) coats bloodstream form Trypanosoma brucei parasites, and monoallelic VSG expression underpins the antigenic variation necessary for pathogenicity. One of thousands of VSG genes is transcribed by RNA polymerase I in a singular nuclear structure called the expression site body (ESB), but how monoallelic VSG transcription is achieved remains unclear. Using a localization screen of 153 proteins we found one, ESB-specific protein 1 (ESB1), that localized only to the ESB and is expressed only in VSG-expressing life cycle stages. ESB1 associates with DNA near the active VSG promoter and is necessary for VSG expression, with overexpression activating inactive VSG promoters. Mechanistically, ESB1 is necessary for recruitment of a subset of ESB components, including RNA polymerase I, revealing that the ESB has separately assembled subdomains. Because many trypanosomatid parasites have divergent ESB1 orthologues yet do not undergo antigenic variation, ESB1 probably represents an important class of transcription regulators.
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Affiliation(s)
| | - Benjamin Hänisch
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Clare Halliday
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Midori Ishii
- Department of Biochemistry, University of Oxford, Oxford, UK
| | - Bungo Akiyoshi
- Department of Biochemistry, University of Oxford, Oxford, UK
| | - Samuel Dean
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK.,Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, UK
| | - Jack Daniel Sunter
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, UK.
| | | | - Keith Gull
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
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Kent RS, Briggs EM, Colon BL, Alvarez C, Silva Pereira S, De Niz M. Paving the Way: Contributions of Big Data to Apicomplexan and Kinetoplastid Research. Front Cell Infect Microbiol 2022; 12:900878. [PMID: 35734575 PMCID: PMC9207352 DOI: 10.3389/fcimb.2022.900878] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 05/06/2022] [Indexed: 11/13/2022] Open
Abstract
In the age of big data an important question is how to ensure we make the most out of the resources we generate. In this review, we discuss the major methods used in Apicomplexan and Kinetoplastid research to produce big datasets and advance our understanding of Plasmodium, Toxoplasma, Cryptosporidium, Trypanosoma and Leishmania biology. We debate the benefits and limitations of the current technologies, and propose future advancements that may be key to improving our use of these techniques. Finally, we consider the difficulties the field faces when trying to make the most of the abundance of data that has already been, and will continue to be, generated.
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Affiliation(s)
- Robyn S. Kent
- Department of Microbiology and Molecular Genetics, University of Vermont, Burlington, VT, United States
| | - Emma M. Briggs
- Institute for Immunology and Infection Research, School of Biological Sciences, University Edinburgh, Edinburgh, United Kingdom
- Wellcome Centre for Integrative Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, United Kingdom
| | - Beatrice L. Colon
- Wellcome Centre for Anti-Infectives Research, Division of Biological Chemistry and Drug Discovery, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Catalina Alvarez
- de Duve Institute, Université Catholique de Louvain, Brussels, Belgium
| | - Sara Silva Pereira
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina da Universidade de Lisboa, Lisboa, Portugal
| | - Mariana De Niz
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina da Universidade de Lisboa, Lisboa, Portugal
- Institut Pasteur, Paris, France
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20
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Howick VM, Peacock L, Kay C, Collett C, Gibson W, Lawniczak MKN. Single-cell transcriptomics reveals expression profiles of Trypanosoma brucei sexual stages. PLoS Pathog 2022; 18:e1010346. [PMID: 35255094 PMCID: PMC8939820 DOI: 10.1371/journal.ppat.1010346] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 03/22/2022] [Accepted: 02/06/2022] [Indexed: 01/26/2023] Open
Abstract
Early diverging lineages such as trypanosomes can provide clues to the evolution of sexual reproduction in eukaryotes. In Trypanosoma brucei, the pathogen that causes Human African Trypanosomiasis, sexual reproduction occurs in the salivary glands of the insect host, but analysis of the molecular signatures that define these sexual forms is complicated because they mingle with more numerous, mitotically-dividing developmental stages. We used single-cell RNA-sequencing (scRNAseq) to profile 388 individual trypanosomes from midgut, proventriculus, and salivary glands of infected tsetse flies allowing us to identify tissue-specific cell types. Further investigation of salivary gland parasite transcriptomes revealed fine-scale changes in gene expression over a developmental progression from putative sexual forms through metacyclics expressing variant surface glycoprotein genes. The cluster of cells potentially containing sexual forms was characterized by high level transcription of the gamete fusion protein HAP2, together with an array of surface proteins and several genes of unknown function. We linked these expression patterns to distinct morphological forms using immunofluorescence assays and reporter gene expression to demonstrate that the kinetoplastid-conserved gene Tb927.10.12080 is exclusively expressed at high levels by meiotic intermediates and gametes. Further experiments are required to establish whether this protein, currently of unknown function, plays a role in gamete formation and/or fusion.
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Affiliation(s)
- Virginia M. Howick
- Institute of Biodiversity, Animal Health, and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
- Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, United Kingdom
- Parasites and Microbes Programme, Wellcome Sanger Institute, Hinxton, United Kingdom
| | - Lori Peacock
- School of Biological Sciences, University of Bristol, Bristol, United Kingdom
- Bristol Veterinary School, University of Bristol, Langford, United Kingdom
| | - Chris Kay
- School of Biological Sciences, University of Bristol, Bristol, United Kingdom
| | - Clare Collett
- School of Biological Sciences, University of Bristol, Bristol, United Kingdom
| | - Wendy Gibson
- School of Biological Sciences, University of Bristol, Bristol, United Kingdom
| | - Mara K. N. Lawniczak
- Parasites and Microbes Programme, Wellcome Sanger Institute, Hinxton, United Kingdom
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Nakada-Tsukui K, Nozaki T. Trogocytosis in Unicellular Eukaryotes. Cells 2021; 10:cells10112975. [PMID: 34831198 PMCID: PMC8616307 DOI: 10.3390/cells10112975] [Citation(s) in RCA: 2] [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: 07/16/2021] [Revised: 09/25/2021] [Accepted: 10/17/2021] [Indexed: 12/12/2022] Open
Abstract
Trogocytosis is a mode of internalization of a part of a live cell by nibbling and is mechanistically distinct from phagocytosis, which implies internalization of a whole cell or a particle. Trogocytosis has been demonstrated in a broad range of cell types in multicellular organisms and is also known to be involved in a plethora of functions. In immune cells, trogocytosis is involved in the "cross-dressing" between antigen presenting cells and T cells, and is thus considered to mediate intercellular communication. On the other hand, trogocytosis has also been reported in a variety of unicellular organisms including the protistan (protozoan) parasite Entamoeba histolytica. E. histolytica ingests human T cell line by trogocytosis and acquires complement resistance and cross-dresses major histocompatibility complex (MHC) class I on the cell surface. Furthermore, trogocytosis and trogocytosis-like phenomena (nibbling of a live cell, not previously described as trogocytosis) have also been reported in other parasitic protists such as Trichomonas, Plasmodium, Toxoplasma, and free-living amoebae. Thus, trogocytosis is conserved in diverse eukaryotic supergroups as a means of intercellular communication. It is depicting the universality of trogocytosis among eukaryotes. In this review, we summarize our current understanding of trogocytosis in unicellular organisms, including the history of its discovery, taxonomical distribution, roles, and molecular mechanisms.
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Affiliation(s)
- Kumiko Nakada-Tsukui
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo 162-8640, Japan
- Correspondence: (K.N.-T.); (T.N.); Tel.: +81-3-5285-1111 (K.N.-T.); +81-3-5841-3526 (T.N.)
| | - Tomoyoshi Nozaki
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo 113-8654, Japan
- Correspondence: (K.N.-T.); (T.N.); Tel.: +81-3-5285-1111 (K.N.-T.); +81-3-5841-3526 (T.N.)
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Cosentino RO, Brink BG, Siegel TN. Allele-specific assembly of a eukaryotic genome corrects apparent frameshifts and reveals a lack of nonsense-mediated mRNA decay. NAR Genom Bioinform 2021; 3:lqab082. [PMID: 34541528 PMCID: PMC8445201 DOI: 10.1093/nargab/lqab082] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 08/25/2021] [Accepted: 09/06/2021] [Indexed: 11/14/2022] Open
Abstract
To date, most reference genomes represent a mosaic consensus sequence in which the homologous chromosomes are collapsed into one sequence. This approach produces sequence artefacts and impedes analyses of allele-specific mechanisms. Here, we report an allele-specific genome assembly of the diploid parasite Trypanosoma brucei and reveal allelic variants affecting gene expression. Using long-read sequencing and chromosome conformation capture data, we could assign 99.5% of all heterozygote variants to a specific homologous chromosome and build a 66 Mb long allele-specific genome assembly. The phasing of haplotypes allowed us to resolve hundreds of artefacts present in the previous mosaic consensus assembly. In addition, it revealed allelic recombination events, visible as regions of low allelic heterozygosity, enabling the lineage tracing of T. brucei isolates. Interestingly, analyses of transcriptome and translatome data of genes with allele-specific premature termination codons point to the absence of a nonsense-mediated decay mechanism in trypanosomes. Taken together, this study delivers a reference quality allele-specific genome assembly of T. brucei and demonstrates the importance of such assemblies for the study of gene expression control. We expect the new genome assembly will increase the awareness of allele-specific phenomena and provide a platform to investigate them.
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Affiliation(s)
- Raúl O Cosentino
- Division of Experimental Parasitology, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität in Munich, Lena-Christ-Str. 48, Planegg-Martinsried 82152, Germany
| | - Benedikt G Brink
- Division of Experimental Parasitology, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität in Munich, Lena-Christ-Str. 48, Planegg-Martinsried 82152, Germany
| | - T Nicolai Siegel
- Division of Experimental Parasitology, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität in Munich, Lena-Christ-Str. 48, Planegg-Martinsried 82152, Germany
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23
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Corrales RM, Vaselek S, Neish R, Berry L, Brunet CD, Crobu L, Kuk N, Mateos-Langerak J, Robinson DR, Volf P, Mottram JC, Sterkers Y, Bastien P. The kinesin of the flagellum attachment zone in Leishmania is required for cell morphogenesis, cell division and virulence in the mammalian host. PLoS Pathog 2021; 17:e1009666. [PMID: 34143858 PMCID: PMC8244899 DOI: 10.1371/journal.ppat.1009666] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 06/30/2021] [Accepted: 05/24/2021] [Indexed: 11/20/2022] Open
Abstract
Leishmania parasites possess a unique and complex cytoskeletal structure termed flagellum attachment zone (FAZ) connecting the base of the flagellum to one side of the flagellar pocket (FP), an invagination of the cell body membrane and the sole site for endocytosis and exocytosis. This structure is involved in FP architecture and cell morphogenesis, but its precise role and molecular composition remain enigmatic. Here, we characterized Leishmania FAZ7, the only known FAZ protein containing a kinesin motor domain, and part of a clade of trypanosomatid-specific kinesins with unknown functions. The two paralogs of FAZ7, FAZ7A and FAZ7B, display different localizations and functions. FAZ7A localizes at the basal body, while FAZ7B localizes at the distal part of the FP, where the FAZ structure is present in Leishmania. While null mutants of FAZ7A displayed normal growth rates, the deletion of FAZ7B impaired cell growth in both promastigotes and amastigotes of Leishmania. The kinesin activity is crucial for its function. Deletion of FAZ7B resulted in altered cell division, cell morphogenesis (including flagellum length), and FP structure and function. Furthermore, knocking out FAZ7B induced a mis-localization of two of the FAZ proteins, and disrupted the molecular organization of the FP collar, affecting the localization of its components. Loss of the kinesin FAZ7B has important consequences in the insect vector and mammalian host by reducing proliferation in the sand fly and pathogenicity in mice. Our findings reveal the pivotal role of the only FAZ kinesin as part of the factors important for a successful life cycle of Leishmania. Leishmania are flagellated trypanosomatid parasites causing worldwide human and animal diseases. As ’divergent eukaryotes’, their biology presents unique features and structures, of which the specific functions constitute potential drug targets. Among others, they possess a unique cytoskeletal structure termed the flagellum attachment zone (FAZ) attaching the base of their flagellum to one side of the flagellar pocket (FP), which is the sole site for endocytosis and exocytosis. The FP together with other unique flagellum-associated structures are crucial for parasite survival, but the functioning of this whole remains largely enigmatic. Leishmania also possess an expanded repertoire of kinesins (>55), including two trypanosomatid-specific families. Here, we show that the deletion of the sole kinesin among FAZ proteins disrupts cell morphogenesis, FP organisation and cell division. Furthermore, the ability to proliferate in the insect vector and mammalian host is reduced in parasites lacking the kinesin FAZ7B. This study helps elucidate the factors contributing to the successful lifecycle and pathogenicity of the parasite. It also highlights the functional diversification of motor proteins during evolution.
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Affiliation(s)
- Rosa Milagros Corrales
- Research Unit “MiVEGEC”, University of Montpellier, CNRS, IRD, Academic Hospital (CHU) of Montpellier, Montpellier, France
- * E-mail: (RMC); (PB)
| | - Slavica Vaselek
- Department of Parasitology, Charles University, Prague, Czech Republic
| | - Rachel Neish
- York Biomedical Research Institute and Department of Biology, University of York, York, United Kingdom
| | - Laurence Berry
- Research Unit “LPHI” (Laboratory of Pathogen Host Interactions), University of Montpellier, CNRS, Montpellier, France
| | - Camille D. Brunet
- Research Unit “MiVEGEC”, University of Montpellier, CNRS, IRD, Academic Hospital (CHU) of Montpellier, Montpellier, France
| | - Lucien Crobu
- Research Unit “MiVEGEC”, University of Montpellier, CNRS, IRD, Academic Hospital (CHU) of Montpellier, Montpellier, France
| | - Nada Kuk
- Research Unit “MiVEGEC”, University of Montpellier, CNRS, IRD, Academic Hospital (CHU) of Montpellier, Montpellier, France
| | | | - Derrick R. Robinson
- Research Unit “Fundamental Microbiology and Pathogenicity”, “Protist Parasite Cytoskeleton (ProParaCyto)”, University of Bordeaux, UMR 5234, CNRS, Bordeaux, France
| | - Petr Volf
- Department of Parasitology, Charles University, Prague, Czech Republic
| | - Jeremy C. Mottram
- York Biomedical Research Institute and Department of Biology, University of York, York, United Kingdom
| | - Yvon Sterkers
- Research Unit “MiVEGEC”, University of Montpellier, CNRS, IRD, Academic Hospital (CHU) of Montpellier, Montpellier, France
| | - Patrick Bastien
- Research Unit “MiVEGEC”, University of Montpellier, CNRS, IRD, Academic Hospital (CHU) of Montpellier, Montpellier, France
- * E-mail: (RMC); (PB)
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24
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Sinclair AN, Huynh CT, Sladewski TE, Zuromski JL, Ruiz AE, de Graffenried CL. The Trypanosoma brucei subpellicular microtubule array is organized into functionally discrete subdomains defined by microtubule associated proteins. PLoS Pathog 2021; 17:e1009588. [PMID: 34010336 PMCID: PMC8168904 DOI: 10.1371/journal.ppat.1009588] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 06/01/2021] [Accepted: 04/25/2021] [Indexed: 11/19/2022] Open
Abstract
Microtubules are inherently dynamic cytoskeletal polymers whose length and organization can be altered to perform essential functions in eukaryotic cells, such as providing tracks for intracellular trafficking and forming the mitotic spindle. Microtubules can be bundled to create more stable structures that collectively propagate force, such as in the flagellar axoneme, which provides motility. The subpellicular microtubule array of the protist parasite Trypanosoma brucei, the causative agent of African sleeping sickness, is a remarkable example of a highly specialized microtubule bundle. It is comprised of a single layer of microtubules that are crosslinked to each other and to the overlying plasma membrane. The array microtubules appear to be highly stable and remain intact throughout the cell cycle, but very little is known about the pathways that tune microtubule properties in trypanosomatids. Here, we show that the subpellicular microtubule array is organized into subdomains that consist of differentially localized array-associated proteins at the array posterior, middle, and anterior. The array-associated protein PAVE1 stabilizes array microtubules at the cell posterior and is essential for maintaining its tapered shape. PAVE1 and the newly identified protein PAVE2 form a complex that binds directly to the microtubule lattice, demonstrating that they are a true kinetoplastid-specific MAP. TbAIR9, which localizes to the entirety of the subpellicular array, is necessary for maintaining the localization of array-associated proteins within their respective subdomains of the array. The arrangement of proteins within the array likely tunes the local properties of array microtubules and creates the asymmetric shape of the cell, which is essential for parasite viability.
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Affiliation(s)
- Amy N. Sinclair
- Department of Molecular Microbiology and Immunology, Brown University, Providence, Rhode Island, United States of America
| | - Christine T. Huynh
- Department of Molecular Microbiology and Immunology, Brown University, Providence, Rhode Island, United States of America
| | - Thomas E. Sladewski
- Department of Molecular Microbiology and Immunology, Brown University, Providence, Rhode Island, United States of America
| | - Jenna L. Zuromski
- Department of Pathology and Laboratory Medicine, Center for International Health Research, Brown University, Providence, Rhode Island, United States of America
| | - Amanda E. Ruiz
- Department of Pathology and Laboratory Medicine, Center for International Health Research, Brown University, Providence, Rhode Island, United States of America
| | - Christopher L. de Graffenried
- Department of Molecular Microbiology and Immunology, Brown University, Providence, Rhode Island, United States of America
- * E-mail:
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25
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Papadaki A, Tziouvara O, Kotopouli A, Koumarianou P, Doukas A, Rios P, Tardieux I, Köhn M, Boleti H. The Leishmania donovani LDBPK_220120.1 Gene Encodes for an Atypical Dual Specificity Lipid-Like Phosphatase Expressed in Promastigotes and Amastigotes; Substrate Specificity, Intracellular Localizations, and Putative Role(s). Front Cell Infect Microbiol 2021; 11:591868. [PMID: 33842381 PMCID: PMC8027504 DOI: 10.3389/fcimb.2021.591868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 01/25/2021] [Indexed: 11/13/2022] Open
Abstract
The intracellular protozoan parasites of the Leishmania genus are responsible for Leishmaniases, vector borne diseases with a wide range of clinical manifestations. Leishmania (L.) donovani causes visceral leishmaniasis (kala azar), the most severe of these diseases. Along their biological cycle, Leishmania parasites undergo distinct developmental transitions including metacyclogenesis and differentiation of metacyclic promastigotes (MPs) to amastigotes. Metacyclogenesis inside the phlebotomine sandfly host's midgut converts the procyclic dividing promastigotes to non-dividing infective MPs eventually injected into the skin of mammalian hosts and phagocytosed by macrophages where the MPs are converted inside modified phagolysosomes to the intracellular amastigotes. These developmental transitions involve dramatic changes in cell size and shape and reformatting of the flagellum requiring thus membrane and cytoskeleton remodeling in which phosphoinositide (PI) signaling and metabolism must play central roles. This study reports on the LDBPK_220120.1 gene, the L. donovani ortholog of LmjF.22.0250 from L. major that encodes a phosphatase from the "Atypical Lipid Phosphatases" (ALPs) enzyme family. We confirmed the expression of the LDBPK_220120.1 gene product in both L. donovani promastigotes and axenic amastigotes and showed that it behaves in vitro as a Dual Specificity P-Tyr and monophosphorylated [PI(3)P and PI(4)P] PI phosphatase and therefore named it LdTyrPIP_22 (Leishmaniad onovani Tyrosine PI Phosphatase, gene locus at chromosome 22). By immunofluorescence confocal microscopy we localized the LdTyrPIP_22 in several intracellular sites in the cell body of L. donovani promastigotes and amastigotes and in the flagellum. A temperature and pH shift from 25°C to 37°C and from pH 7 to 5.5, induced a pronounced recruitment of LdTyrPIP_22 epitopes to the flagellar pocket and a redistribution around the nucleus. These results suggest possible role(s) for this P-Tyr/PI phosphatase in the regulation of processes initiated or upregulated by this temperature/pH shift that contribute to the developmental transition from MPs to amastigotes inside the mammalian host macrophages.
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Affiliation(s)
- Amalia Papadaki
- Intracellular Parasitism Laboratory, Department of Microbiology, Hellenic Pasteur Institute, Athens, Greece
| | - Olympia Tziouvara
- Intracellular Parasitism Laboratory, Department of Microbiology, Hellenic Pasteur Institute, Athens, Greece
| | - Anastasia Kotopouli
- Intracellular Parasitism Laboratory, Department of Microbiology, Hellenic Pasteur Institute, Athens, Greece
| | - Petrina Koumarianou
- Intracellular Parasitism Laboratory, Department of Microbiology, Hellenic Pasteur Institute, Athens, Greece.,Light Microscopy Unit, Hellenic Pasteur Institute, Athens, Greece
| | - Anargyros Doukas
- Intracellular Parasitism Laboratory, Department of Microbiology, Hellenic Pasteur Institute, Athens, Greece
| | - Pablo Rios
- Genome Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany.,Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, Germany.,Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Isabelle Tardieux
- Team «Biomechanics of Host Parasite Interactions», Institut for Advanced BioSciences, Univ. Grenoble Alpes, Inserm U1209 - CNRS UMR 5309, 38700 La Tronche, France
| | - Maja Köhn
- Genome Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany.,Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, Germany.,Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Haralabia Boleti
- Intracellular Parasitism Laboratory, Department of Microbiology, Hellenic Pasteur Institute, Athens, Greece.,Light Microscopy Unit, Hellenic Pasteur Institute, Athens, Greece
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26
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Baker N, Catta-Preta CMC, Neish R, Sadlova J, Powell B, Alves-Ferreira EVC, Geoghegan V, Carnielli JBT, Newling K, Hughes C, Vojtkova B, Anand J, Mihut A, Walrad PB, Wilson LG, Pitchford JW, Volf P, Mottram JC. Systematic functional analysis of Leishmania protein kinases identifies regulators of differentiation or survival. Nat Commun 2021; 12:1244. [PMID: 33623024 PMCID: PMC7902614 DOI: 10.1038/s41467-021-21360-8] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 01/13/2021] [Indexed: 01/31/2023] Open
Abstract
Differentiation between distinct stages is fundamental for the life cycle of intracellular protozoan parasites and for transmission between hosts, requiring stringent spatial and temporal regulation. Here, we apply kinome-wide gene deletion and gene tagging in Leishmania mexicana promastigotes to define protein kinases with life cycle transition roles. Whilst 162 are dispensable, 44 protein kinase genes are refractory to deletion in promastigotes and are likely core genes required for parasite replication. Phenotyping of pooled gene deletion mutants using bar-seq and projection pursuit clustering reveal functional phenotypic groups of protein kinases involved in differentiation from metacyclic promastigote to amastigote, growth and survival in macrophages and mice, colonisation of the sand fly and motility. This unbiased interrogation of protein kinase function in Leishmania allows targeted investigation of organelle-associated signalling pathways required for successful intracellular parasitism.
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Affiliation(s)
- N Baker
- York Biomedical Research Institute, University of York, York, UK
- Department of Biology, University of York, York, UK
| | - C M C Catta-Preta
- York Biomedical Research Institute, University of York, York, UK
- Department of Biology, University of York, York, UK
| | - R Neish
- York Biomedical Research Institute, University of York, York, UK
- Department of Biology, University of York, York, UK
| | - J Sadlova
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czech Republic
| | - B Powell
- Department of Mathematics, University of York, York, UK
| | - E V C Alves-Ferreira
- York Biomedical Research Institute, University of York, York, UK
- Department of Biology, University of York, York, UK
| | - V Geoghegan
- York Biomedical Research Institute, University of York, York, UK
- Department of Biology, University of York, York, UK
| | - J B T Carnielli
- York Biomedical Research Institute, University of York, York, UK
- Department of Biology, University of York, York, UK
| | - K Newling
- Department of Biology, University of York, York, UK
| | - C Hughes
- York Biomedical Research Institute, University of York, York, UK
- Department of Biology, University of York, York, UK
| | - B Vojtkova
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czech Republic
| | - J Anand
- York Biomedical Research Institute, University of York, York, UK
- Department of Biology, University of York, York, UK
| | - A Mihut
- Department of Biology, University of York, York, UK
| | - P B Walrad
- York Biomedical Research Institute, University of York, York, UK
- Department of Biology, University of York, York, UK
| | - L G Wilson
- York Biomedical Research Institute, University of York, York, UK
- Department of Physics, University of York, York, UK
| | - J W Pitchford
- Department of Biology, University of York, York, UK
- Department of Mathematics, University of York, York, UK
| | - P Volf
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czech Republic
| | - J C Mottram
- York Biomedical Research Institute, University of York, York, UK.
- Department of Biology, University of York, York, UK.
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27
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Gupta CM, Ambaru B, Bajaj R. Emerging Functions of Actins and Actin Binding Proteins in Trypanosomatids. Front Cell Dev Biol 2020; 8:587685. [PMID: 33163497 PMCID: PMC7581878 DOI: 10.3389/fcell.2020.587685] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Accepted: 09/22/2020] [Indexed: 01/20/2023] Open
Abstract
Actin is the major protein constituent of the cytoskeleton that performs wide range of cellular functions. It exists in monomeric and filamentous forms, dynamics of which is regulated by a large repertoire of actin binding proteins. However, not much was known about existence of these proteins in trypanosomatids, till the genome sequence data of three important organisms of this class, viz. Trypanosoma brucei, Trypanosoma cruzi and Leishmania major, became available. Here, we have reviewed most of the findings reported to date on the intracellular distribution, structure and functions of these proteins and based on them, we have hypothesized some of their functions. The major findings are as follows: (1) All the three organisms encode at least a set of ten actin binding proteins (profilin, twinfilin, ADF/cofilin, CAP/srv2, CAPz, coronin, two myosins, two formins) and one isoform of actin, except that T. cruzi encodes for three formins and several myosins along with four actins. (2) Actin 1 and a few actin binding proteins (ADF/cofilin, profilin, twinfilin, coronin and myosin13 in L. donovani; ADF/cofilin, profilin and myosin1 in T. brucei; profilin and myosin-F in T.cruzi) have been identified and characterized. (3) In all the three organisms, actin cytoskeleton has been shown to regulate endocytosis and intracellular trafficking. (4) Leishmania actin1 has been the most characterized protein among trypanosomatid actins. (5) This protein is localized to the cytoplasm as well as in the flagellum, nucleus and kinetoplast, and in vitro, it binds to DNA and displays scDNA relaxing and kDNA nicking activities. (6) The pure protein prefers to form bundles instead of thin filaments, and does not bind DNase1 or phalloidin. (7) Myosin13, myosin1 and myosin-F regulate endocytosis and intracellular trafficking, respectively, in Leishmania, T. brucei and T. cruzi. (8) Actin-dependent myosin13 motor is involved in dynamics and assembly of Leishmania flagellum. (9) Leishmania twinfilin localizes mostly to the nucleolus and coordinates karyokinesis by effecting splindle elongation and DNA synthesis. (10) Leishmania coronin binds and promotes actin filament formation and exists in tetrameric form rather than trimeric form, like other coronins. (11) Trypanosomatid profilins are essential for survival of all the three parasites.
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Affiliation(s)
- Chhitar M Gupta
- Institute of Bioinformatics and Applied Biotechnology, Bengaluru, India
| | - Bindu Ambaru
- Institute of Bioinformatics and Applied Biotechnology, Bengaluru, India.,Manipal Academy of Higher Education, Manipal, India
| | - Rani Bajaj
- Institute of Bioinformatics and Applied Biotechnology, Bengaluru, India.,Manipal Academy of Higher Education, Manipal, India
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28
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Wang Z, Beneke T, Gluenz E, Wheeler RJ. The single flagellum of Leishmania has a fixed polarisation of its asymmetric beat. J Cell Sci 2020; 133:133/20/jcs246637. [PMID: 33093230 PMCID: PMC7595685 DOI: 10.1242/jcs.246637] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Accepted: 09/17/2020] [Indexed: 12/20/2022] Open
Abstract
Eukaryotic flagella undertake different beat types as necessary for different functions; for example, the Leishmania parasite flagellum undergoes a symmetric tip-to-base beat for forward swimming and an asymmetric base-to-tip beat to rotate the cell. In multi-ciliated tissues or organisms, the asymmetric beats are coordinated, leading to movement of the cell, organism or surrounding fluid. This coordination involves a polarisation of power stroke direction. Here, we asked whether the asymmetric beat of the single Leishmania flagellum also has a fixed polarisation. We developed high frame rate dual-colour fluorescence microscopy to visualise flagellar-associated structures in live swimming cells. This showed that the asymmetric Leishmania beat is polarised, with power strokes only occurring in one direction relative to the asymmetric flagellar machinery. Polarisation of bending was retained in deletion mutants whose flagella cannot beat but have a static bend. Furthermore, deletion mutants for proteins required for asymmetric extra-axonemal and rootlet-like flagellum-associated structures also retained normal polarisation. Leishmania beat polarisation therefore likely arises from either the nine-fold rotational symmetry of the axoneme structure or is due to differences between the outer doublet decorations. Highlighted Article: By using high speed, high-resolution fluorescence microscopy of swimming Leishmania cells, we showed that the asymmetric flagellar beat always wafts in the same direction and investigate which structures are involved.
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Affiliation(s)
- Ziyin Wang
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Tom Beneke
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Eva Gluenz
- The Wellcome Centre for Integrative Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, UK
| | - Richard John Wheeler
- Peter Medawar Building for Pathogen Research, Nuffield Department of Medicine, University of Oxford, Oxford, UK
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29
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Yagoubat A, Corrales RM, Bastien P, Lévêque MF, Sterkers Y. Gene Editing in Trypanosomatids: Tips and Tricks in the CRISPR-Cas9 Era. Trends Parasitol 2020; 36:745-760. [DOI: 10.1016/j.pt.2020.06.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 06/19/2020] [Accepted: 06/30/2020] [Indexed: 12/22/2022]
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30
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Basal Body Protein TbSAF1 Is Required for Microtubule Quartet Anchorage to the Basal Bodies in Trypanosoma brucei. mBio 2020; 11:mBio.00668-20. [PMID: 32518185 PMCID: PMC7291619 DOI: 10.1128/mbio.00668-20] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Trypanosoma brucei contains a large array of single-copied organelles and structures. Through extensive interorganelle connections, these structures replicate and divide following a strict temporal and spatial order. A microtubule quartet (MtQ) originates from the basal bodies and extends toward the anterior end of the cell, stringing several cytoskeletal structures together along its path. In this study, we examined the interaction network of TbSpef1, the only protein specifically located to the MtQ. We identified an interaction between TbSpef1 and a basal body protein TbSAF1, which is required for MtQ anchorage to the basal bodies. This study thus provides the first molecular description of MtQ association with the basal bodies, since the discovery of this association ∼30 years ago. The results also reveal a general mechanism of the evolutionarily conserved Spef1/CLAMP, which achieves specific cellular functions via their conserved microtubule functions and their diverse molecular interaction networks. Sperm flagellar protein 1 (Spef1, also known as CLAMP) is a microtubule-associated protein involved in various microtubule-related functions from ciliary motility to polarized cell movement and planar cell polarity. In Trypanosoma brucei, the causative agent of trypanosomiasis, a single Spef1 ortholog (TbSpef1) is associated with a microtubule quartet (MtQ), which is in close association with several single-copied organelles and is required for their coordinated biogenesis during the cell cycle. Here, we investigated the interaction network of TbSpef1 using BioID, a proximity-dependent protein-protein interaction screening method. Characterization of selected candidates provided a molecular description of TbSpef1-MtQ interactions with nearby cytoskeletal structures. Of particular interest, we identified a new basal body protein TbSAF1, which is required for TbSpef1-MtQ anchorage to the basal bodies. The results demonstrate that MtQ-basal body anchorage is critical for the spatial organization of cytoskeletal organelles, as well as the morphology of the membrane-bound flagellar pocket where endocytosis takes place in this parasite.
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31
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Vizcaíno-Castillo A, Osorio-Méndez JF, Ambrosio JR, Hernández R, Cevallos AM. The complexity and diversity of the actin cytoskeleton of trypanosomatids. Mol Biochem Parasitol 2020; 237:111278. [PMID: 32353561 DOI: 10.1016/j.molbiopara.2020.111278] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 03/24/2020] [Accepted: 04/07/2020] [Indexed: 10/24/2022]
Abstract
Trypanosomatids are a monophyletic group of parasitic flagellated protists belonging to the order Kinetoplastida. Their cytoskeleton is primarily made up of microtubules in which no actin microfilaments have been detected. Although all these parasites contain actin, it is widely thought that their actin cytoskeleton is reduced when compared to most eukaryotic organisms. However, there is increasing evidence that it is more complex than previously thought. As in other eukaryotic organisms, trypanosomatids encode for a conventional actin that is expected to form microfilament-like structures, and for members of three conserved actin-related proteins probably involved in microfilament nucleation (ARP2, ARP3) and in gene expression regulation (ARP6). In addition to these canonical proteins, also encode for an expanded set of actins and actin-like proteins that seem to be restricted to kinetoplastids. Analysis of their amino acid sequences demonstrated that, although very diverse in primary sequence when compared to actins of model organisms, modelling of their tertiary structure predicted the presence of the actin fold in all of them. Experimental characterization has been done for only a few of the trypanosomatid actins and actin-binding proteins. The most studied is the conventional actin of Leishmania donovani (LdAct), which unusually requires both ATP and Mg2+ for polymerization, unlike other conventional actins that do not require ATP. Additionally, polymerized LdAct tends to assemble in bundles rather than in single filaments. Regulation of actin polymerization depends on their interaction with actin-binding proteins. In trypanosomatids, there is a reduced but sufficient core of actin-binding proteins to promote microfilament nucleation, turnover and stabilization. There are also genes encoding for members of two families of myosin motor proteins, including one lineage-specific. Homologues to all identified actin-family proteins and actin-binding proteins of trypanosomatids are also present in Paratrypanosoma confusum (an early branching trypanosomatid) and in Bodo saltans (a closely related free-living organism belonging to the trypanosomatid sister order of Bodonida) suggesting they were all present in their common ancestor. Secondary losses of these genes may have occurred during speciation within the trypanosomatids, with salivarian trypanosomes having lost many of them and stercorarian trypanosomes retaining most.
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Affiliation(s)
- Andrea Vizcaíno-Castillo
- Departamento de Biología Molecular y Biotecnología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Av. Universidad 3000, Ciudad Universitaria, Coyoacán, 04510, Ciudad de México, Mexico
| | - Juan Felipe Osorio-Méndez
- Departamento de Biología Molecular y Biotecnología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Av. Universidad 3000, Ciudad Universitaria, Coyoacán, 04510, Ciudad de México, Mexico; Laboratorio de Microbiología y Biología Molecular, Programa de Medicina, Corporación Universitaria Empresarial Alexander von Humboldt, Armenia, Colombia
| | - Javier R Ambrosio
- Departamento de Microbiología y Parasitología de la Facultad de Medicina, Universidad Nacional Autónoma de México, Apartado Postal, 4510, D.F., Mexico
| | - Roberto Hernández
- Departamento de Biología Molecular y Biotecnología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Av. Universidad 3000, Ciudad Universitaria, Coyoacán, 04510, Ciudad de México, Mexico
| | - Ana María Cevallos
- Departamento de Biología Molecular y Biotecnología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Av. Universidad 3000, Ciudad Universitaria, Coyoacán, 04510, Ciudad de México, Mexico.
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32
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A Global Analysis of Enzyme Compartmentalization to Glycosomes. Pathogens 2020; 9:pathogens9040281. [PMID: 32290588 PMCID: PMC7237986 DOI: 10.3390/pathogens9040281] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 04/08/2020] [Accepted: 04/09/2020] [Indexed: 12/28/2022] Open
Abstract
In kinetoplastids, the first seven steps of glycolysis are compartmentalized into a glycosome along with parts of other metabolic pathways. This organelle shares a common ancestor with the better-understood eukaryotic peroxisome. Much of our understanding of the emergence, evolution, and maintenance of glycosomes is limited to explorations of the dixenous parasites, including the enzymatic contents of the organelle. Our objective was to determine the extent that we could leverage existing studies in model kinetoplastids to determine the composition of glycosomes in species lacking evidence of experimental localization. These include diverse monoxenous species and dixenous species with very different hosts. For many of these, genome or transcriptome sequences are available. Our approach initiated with a meta-analysis of existing studies to generate a subset of enzymes with highest evidence of glycosome localization. From this dataset we extracted the best possible glycosome signal peptide identification scheme for in silico identification of glycosomal proteins from any kinetoplastid species. Validation suggested that a high glycosome localization score from our algorithm would be indicative of a glycosomal protein. We found that while metabolic pathways were consistently represented across kinetoplastids, individual proteins within those pathways may not universally exhibit evidence of glycosome localization.
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33
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ImageJ for Partially and Fully Automated Analysis of Trypanosome Micrographs. Methods Mol Biol 2020. [PMID: 32221933 DOI: 10.1007/978-1-0716-0294-2_24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/07/2023]
Abstract
Trypanosomes and related parasites such as Leishmania are unicellular parasites with a precise internal structure. This makes light microscopy a powerful tool for interrogating their biology-whether considering advance techniques for visualizing the precise localization of proteins within the cell or simply measuring parasite cell shape. Methods to partially or fully automate analysis and interpretation are extremely powerful and provide easier access to microscope images as a source of quantitative data. This chapter provides an introduction to these methods using ImageJ/FIJI, free and open source software for scientific image analysis. It provides an overview of how ImageJ handles images and introduces the ImageJ macro/scripting language for automated images, starting at a basic level and assuming no previous programming/scripting experience. It then outlines three methods using ImageJ for automated analysis of trypanosome micrographs: Semiautomated cropping and setting image contrast for presentation, automated analysis of cell properties from a light micrograph field of view, and example semiautomated tools for quantitative analysis of protein localization. These are not presented as strict methods, but are instead described in detail with the intention of furnishing the reader with the ability to "hack" the scripts for their own needs or write their own scripts for partially and fully automated quantitation of trypanosomes from light micrographs. Most of the methods described here are transferrable to other types of microscope image and other cell types.
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34
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Nerusheva OO, Ludzia P, Akiyoshi B. Identification of four unconventional kinetoplastid kinetochore proteins KKT22-25 in Trypanosoma brucei. Open Biol 2019; 9:190236. [PMID: 31795916 PMCID: PMC6936259 DOI: 10.1098/rsob.190236] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The kinetochore is a multi-protein complex that drives chromosome segregation in eukaryotes. It assembles onto centromere DNA and interacts with spindle microtubules during mitosis and meiosis. Although most eukaryotes have canonical kinetochore proteins, kinetochores of evolutionarily divergent kinetoplastid species consist of at least 20 unconventional kinetochore proteins (KKT1–20). In addition, 12 proteins (KKT-interacting proteins 1–12, KKIP1–12) are known to localize at kinetochore regions during mitosis. It remains unclear whether KKIP proteins interact with KKT proteins. Here, we report the identification of four additional kinetochore proteins, KKT22–25, in Trypanosoma brucei. KKT22 and KKT23 constitutively localize at kinetochores, while KKT24 and KKT25 localize from S phase to anaphase. KKT23 has a Gcn5-related N-acetyltransferase domain, which is not found in any kinetochore protein known to date. We also show that KKIP1 co-purifies with KKT proteins, but not with KKIP proteins. Finally, our affinity purification of KKIP2/3/4/6 identifies a number of proteins as their potential interaction partners, many of which are implicated in RNA binding or processing. These findings further support the idea that kinetoplastid kinetochores are unconventional.
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Affiliation(s)
- Olga O Nerusheva
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK
| | - Patryk Ludzia
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK
| | - Bungo Akiyoshi
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK
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Wang Z, Wheeler RJ, Sunter JD. Lysosome assembly and disassembly changes endocytosis rate through the Leishmania cell cycle. Microbiologyopen 2019; 9:e969. [PMID: 31743959 PMCID: PMC7002101 DOI: 10.1002/mbo3.969] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 10/29/2019] [Accepted: 10/30/2019] [Indexed: 01/03/2023] Open
Abstract
The Leishmania lysosome has an atypical structure, consisting of an elongated vesicle‐filled tubule running along the anterior–posterior axis of the cell, which is termed the multivesicular tubule (MVT) lysosome. Alongside, the MVT lysosome is one or more microtubules, the lysosomal microtubule(s). Previous work indicated there were cell cycle‐related changes in MVT lysosome organization; however, these only provided snapshots and did not connect the changes in the lysosomal microtubule(s) or lysosomal function. Using mNeonGreen tagged cysteine peptidase A and SPEF1 as markers of the MVT lysosome and lysosomal microtubule(s), we examined the dynamics of these structures through the cell cycle. Both the MVT lysosome and lysosomal microtubule(s) elongated at the beginning of the cell cycle before plateauing and then disassembling in late G2 before cytokinesis. Moreover, the endocytic rate in cells where the MVT lysosome and lysosomal microtubule(s) had disassembled was extremely low. The dynamic nature of the MVT lysosome and lysosomal microtubule(s) parallels that of the Trypanosoma cruzi cytostome/cytopharynx, which also has a similar membrane tubule structure with associated microtubules. As the cytostome/cytopharynx is an ancestral feature of the kinetoplastids, this suggests that the Leishmania MVT lysosome and lysosomal microtubule(s) are a reduced cytostome/cytopharynx‐like feature.
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Affiliation(s)
- Ziyin Wang
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Richard J Wheeler
- The Peter Medawar Building for Pathogen Research, University of Oxford, Oxford, UK
| | - Jack D Sunter
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, UK
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Grewal JS, Catta-Preta CM, Brown E, Anand J, Mottram JC. Evaluation of clan CD C11 peptidase PNT1 and other Leishmania mexicana cysteine peptidases as potential drug targets. Biochimie 2019; 166:150-160. [DOI: 10.1016/j.biochi.2019.08.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 08/26/2019] [Indexed: 10/26/2022]
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Sinclair AN, de Graffenried CL. More than Microtubules: The Structure and Function of the Subpellicular Array in Trypanosomatids. Trends Parasitol 2019; 35:760-777. [PMID: 31471215 PMCID: PMC6783356 DOI: 10.1016/j.pt.2019.07.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 07/25/2019] [Accepted: 07/26/2019] [Indexed: 10/26/2022]
Abstract
The subpellicular microtubule array defines the wide range of cellular morphologies found in parasitic kinetoplastids (trypanosomatids). Morphological studies have characterized array organization, but little progress has been made towards identifying the molecular mechanisms that are responsible for array differentiation during the trypanosomatid life cycle, or the apparent stability and longevity of array microtubules. In this review, we outline what is known about the structure and biogenesis of the array, with emphasis on Trypanosoma brucei, Trypanosoma cruzi, and Leishmania, which cause life-threatening diseases in humans and livestock. We highlight unanswered questions about this remarkable cellular structure that merit new consideration in light of our recently improved understanding of how the 'tubulin code' influences microtubule dynamics to generate complex cellular structures.
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Affiliation(s)
- Amy N Sinclair
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI 02912, USA
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Abstract
Trypanosomes have complex life cycles within which there are both proliferative and differentiation cell divisions. The coordination of the cell cycle to achieve these different divisions is critical for the parasite to infect both host and vector. From studying the regulation of the proliferative cell cycle of the Trypanosoma brucei procyclic life cycle stage, three subcycles emerge that control the duplication and segregation of ( a) the nucleus, ( b) the kinetoplast, and ( c) a set of cytoskeletal structures. We discuss how the clear dependency relationships within these subcycles, and the potential for cross talk between them, are likely required for overall cell cycle coordination. Finally, we look at the implications this interdependence has for proliferative and differentiation divisions through the T. brucei life cycle and in related parasitic trypanosomatid species.
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Affiliation(s)
- Richard J. Wheeler
- Nuffield Department of Medicine, University of Oxford, Oxford OX1 3SY, United Kingdom
| | - Keith Gull
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, United Kingdom
| | - Jack D. Sunter
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford OX3 0BP, United Kingdom
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Contribution of Cytidine Deaminase to Thymidylate Biosynthesis in Trypanosoma brucei: Intracellular Localization and Properties of the Enzyme. mSphere 2019; 4:4/4/e00374-19. [PMID: 31391279 PMCID: PMC6686228 DOI: 10.1128/msphere.00374-19] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Cytidine deaminase (CDA) is a pyrimidine salvage enzyme that catalyzes cytidine and deoxycytidine hydrolytic deamination to yield uridine and deoxyuridine. Here we report the biochemical characterization of Trypanosoma brucei CDA as an enzyme within the tetrameric class of the CDA family that efficiently deaminates cytidine, deoxycytidine, and the nucleoside analogue 5-methyl-2'-deoxycytidine. In line with previous studies, we show that RNA interference (RNAi)-mediated CDA depletion impairs T. brucei proliferation when grown in pyrimidine-deficient medium, while supplementation with thymidine or deoxyuridine restores growth, further underscoring the role of this enzyme in providing deoxyuridine for dUMP formation via thymidine kinase, the substrate required for de novo thymidylate biosynthesis. This observation contrasts with the existence in T. brucei of a dimeric deoxyuridine 5'-triphosphate nucleotidohydrolase (dUTPase), an essential enzyme that can produce dUMP via the hydrolysis of dUTP/dUDP. Thus, T. brucei dUTPase-null mutants are thymidine auxotrophs, suggesting that dUTPase might have a role in providing dUMP for thymidylate biosynthesis. We show that overexpression of human dCMP deaminase (DCTD), an enzyme that provides directly dUMP through dCMP deamination, does not reverse the lethal phenotype of dUTPase knockout cells, which further supports the notion that in T. brucei, CDA is uniquely involved in providing dUMP, while the main role of dUTPase would be the withdrawal of the excess of dUTP to avoid its incorporation into DNA. Furthermore, we report the mitochondrial localization of CDA, highlighting the importance of this organelle in pyrimidine metabolism.IMPORTANCE Cytidine deaminases (CDAs) catalyze the hydrolytic deamination of cytidine and deoxycytidine in the pyrimidine salvage pathway. In kinetoplastids, pyrimidine metabolism has been extensively studied as a source of potential drug targets, given the fact that many of the enzymes of the pathway are essential. Thymidylate (dTMP) synthesis in Trypanosoma brucei exhibits unique characteristics. Thus, it has been suggested that the production of dUMP, the substrate for dTMP formation, is solely dependent on cytidine deaminase and thymidine kinase. Here we characterize recombinant T. brucei CDA (TbCDA) and present evidence that indeed the alternative route for dUMP formation via deoxyuridine 5'-triphosphate nucleotidohydrolase does not have a prominent role in de novo dTMP formation. Furthermore, we provide a scheme for the compartmentalization of dTMP biosynthesis, taking into account the observation that CDA is located in the mitochondrion, together with available information on the intracellular localization of other enzymes involved in the dTTP biosynthetic pathway.
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Dean S, Moreira-Leite F, Gull K. Basalin is an evolutionarily unconstrained protein revealed via a conserved role in flagellum basal plate function. eLife 2019; 8:42282. [PMID: 30810527 PMCID: PMC6392502 DOI: 10.7554/elife.42282] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 02/11/2019] [Indexed: 01/15/2023] Open
Abstract
Most motile flagella have an axoneme that contains nine outer microtubule doublets and a central pair (CP) of microtubules. The CP coordinates the flagellar beat and defects in CP projections are associated with motility defects and human disease. The CP nucleate near a ‘basal plate’ at the distal end of the transition zone (TZ). Here, we show that the trypanosome TZ protein ‘basalin’ is essential for building the basal plate, and its loss is associated with CP nucleation defects, inefficient recruitment of CP assembly factors to the TZ, and flagellum paralysis. Guided by synteny, we identified a highly divergent basalin ortholog in the related Leishmania species. Basalins are predicted to be highly unstructured, suggesting they may act as ‘hubs’ facilitating many protein-protein interactions. This raises the general concept that proteins involved in cytoskeletal functions and appearing organism-specific, may have highly divergent and cryptic orthologs in other species.
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Affiliation(s)
- Samuel Dean
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Flavia Moreira-Leite
- 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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