1
|
Swapna LS, Stevens GC, Sardinha-Silva A, Hu LZ, Brand V, Fusca DD, Wan C, Xiong X, Boyle JP, Grigg ME, Emili A, Parkinson J. ToxoNet: A high confidence map of protein-protein interactions in Toxoplasma gondii. PLoS Comput Biol 2024; 20:e1012208. [PMID: 38900844 PMCID: PMC11219001 DOI: 10.1371/journal.pcbi.1012208] [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: 10/18/2023] [Revised: 07/02/2024] [Accepted: 05/28/2024] [Indexed: 06/22/2024] Open
Abstract
The apicomplexan intracellular parasite Toxoplasma gondii is a major food borne pathogen that is highly prevalent in the global population. The majority of the T. gondii proteome remains uncharacterized and the organization of proteins into complexes is unclear. To overcome this knowledge gap, we used a biochemical fractionation strategy to predict interactions by correlation profiling. To overcome the deficit of high-quality training data in non-model organisms, we complemented a supervised machine learning strategy, with an unsupervised approach, based on similarity network fusion. The resulting combined high confidence network, ToxoNet, comprises 2,063 interactions connecting 652 proteins. Clustering identifies 93 protein complexes. We identified clusters enriched in mitochondrial machinery that include previously uncharacterized proteins that likely represent novel adaptations to oxidative phosphorylation. Furthermore, complexes enriched in proteins localized to secretory organelles and the inner membrane complex, predict additional novel components representing novel targets for detailed functional characterization. We present ToxoNet as a publicly available resource with the expectation that it will help drive future hypotheses within the research community.
Collapse
Affiliation(s)
| | - Grant C. Stevens
- Program in Molecular Medicine, Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Aline Sardinha-Silva
- Molecular Parasitology Section, Laboratory of Parasitic Diseases, NIAID, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Lucas Zhongming Hu
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Verena Brand
- Program in Molecular Medicine, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Daniel D. Fusca
- Program in Molecular Medicine, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Cuihong Wan
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Xuejian Xiong
- Program in Molecular Medicine, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Jon P. Boyle
- Department of Biological Sciences, Dietrich School of Arts and Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Michael E. Grigg
- Molecular Parasitology Section, Laboratory of Parasitic Diseases, NIAID, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Andrew Emili
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
- Department of Biology and Biochemistry, Boston University, Boston, Massachusetts, United States of America
| | - John Parkinson
- Program in Molecular Medicine, Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| |
Collapse
|
2
|
Shi Y, Jiang Y, Qiu H, Hu D, Song X. Mitochondrial dysfunction induced by bedaquiline as an anti-Toxoplasma alternative. Vet Res 2023; 54:123. [PMID: 38115043 PMCID: PMC10731829 DOI: 10.1186/s13567-023-01252-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: 04/26/2023] [Accepted: 09/29/2023] [Indexed: 12/21/2023] Open
Abstract
Toxoplasma gondii is a zoonotic parasite that infects one-third of the world's population and nearly all warm-blooded animals. Due to the complexity of T. gondii's life cycle, available treatment options have limited efficacy. Thus, there is an urgent need to develop new compounds or repurpose existing drugs with potent anti-Toxoplasma activity. This study demonstrates that bedaquiline (BDQ), an FDA-approved diarylquinoline antimycobacterial drug for the treatment of tuberculosis, potently inhibits the tachyzoites of T. gondii. At a safe concentration, BDQ displayed a dose-dependent inhibition on T. gondii growth with a half-maximal effective concentration (EC50) of 4.95 μM. Treatment with BDQ significantly suppressed the proliferation of T. gondii tachyzoites in the host cell, while the invasion ability of the parasite was not affected. BDQ incubation shrunk the mitochondrial structure and decreased the mitochondrial membrane potential and ATP level of T. gondii parasites. In addition, BDQ induced elevated ROS and led to autophagy in the parasite. By transcriptomic analysis, we found that oxidative phosphorylation pathway genes were significantly disturbed by BDQ-treated parasites. More importantly, BDQ significantly reduces brain cysts for the chronically infected mice. These results suggest that BDQ has potent anti-T. gondii activity and may impair its mitochondrial function by affecting proton transport. This study provides bedaquiline as a potential alternative drug for the treatment of toxoplasmosis, and our findings may facilitate the development of new effective drugs for the treatment of toxoplasmosis.
Collapse
Affiliation(s)
- Yuehong Shi
- College of Animal Science and Technology, Guangxi University, Nanning, 530004, China
| | - Yucong Jiang
- College of Animal Science and Technology, Guangxi University, Nanning, 530004, China
| | - Haolong Qiu
- College of Animal Science and Technology, Guangxi University, Nanning, 530004, China
| | - Dandan Hu
- College of Animal Science and Technology, Guangxi University, Nanning, 530004, China
- Guangxi Zhuang Autonomous Region Engineering Research Center of Veterinary Biologics, Nanning, 530004, China
- Guangxi Key Laboratory of Animal Breeding, Disease Control and Prevention, Nanning, 530004, China
| | - Xingju Song
- College of Animal Science and Technology, Guangxi University, Nanning, 530004, China.
- Guangxi Zhuang Autonomous Region Engineering Research Center of Veterinary Biologics, Nanning, 530004, China.
- Guangxi Key Laboratory of Animal Breeding, Disease Control and Prevention, Nanning, 530004, China.
| |
Collapse
|
3
|
Usey MM, Huet D. ATP synthase-associated coiled-coil-helix-coiled-coil-helix (CHCH) domain-containing proteins are critical for mitochondrial function in Toxoplasma gondii. mBio 2023; 14:e0176923. [PMID: 37796022 PMCID: PMC10653836 DOI: 10.1128/mbio.01769-23] [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: 07/10/2023] [Accepted: 08/21/2023] [Indexed: 10/06/2023] Open
Abstract
IMPORTANCE Members of the coiled-coil-helix-coiled-coil-helix (CHCH) domain protein family are transported into the mitochondrial intermembrane space, where they play important roles in the biogenesis and function of the organelle. Unexpectedly, the ATP synthase of the apicomplexan Toxoplasma gondii harbors CHCH domain-containing subunits of unknown function. As no other ATP synthase studied to date contains this class of proteins, characterizing their function will be of broad interest to the fields of molecular parasitology and mitochondrial evolution. Here, we demonstrate that that two T. gondii ATP synthase subunits containing CHCH domains are required for parasite survival and for stability and function of the ATP synthase. We also show that knockdown disrupts multiple aspects of the mitochondrial morphology of T. gondii and that mutation of key residues in the CHCH domains caused mis-localization of the proteins. This work provides insight into the unique features of the apicomplexan ATP synthase, which could help to develop therapeutic interventions against this parasite and other apicomplexans, such as the malaria-causing parasite Plasmodium falciparum.
Collapse
Affiliation(s)
- Madelaine M. Usey
- Department of Cellular Biology, University of Georgia, Athens, Georgia, USA
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
| | - Diego Huet
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens, Georgia, USA
| |
Collapse
|
4
|
Lamb IM, Okoye IC, Mather MW, Vaidya AB. Unique Properties of Apicomplexan Mitochondria. Annu Rev Microbiol 2023; 77:541-560. [PMID: 37406344 DOI: 10.1146/annurev-micro-032421-120540] [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] [Indexed: 07/07/2023]
Abstract
Apicomplexan parasites constitute more than 6,000 species infecting a wide range of hosts. These include important pathogens such as those causing malaria and toxoplasmosis. Their evolutionary emergence coincided with the dawn of animals. Mitochondrial genomes of apicomplexan parasites have undergone dramatic reduction in their coding capacity, with genes for only three proteins and ribosomal RNA genes present in scrambled fragments originating from both strands. Different branches of the apicomplexans have undergone rearrangements of these genes, with Toxoplasma having massive variations in gene arrangements spread over multiple copies. The vast evolutionary distance between the parasite and the host mitochondria has been exploited for the development of antiparasitic drugs, especially those used to treat malaria, wherein inhibition of the parasite mitochondrial respiratory chain is selectively targeted with little toxicity to the host mitochondria. We describe additional unique characteristics of the parasite mitochondria that are being investigated and provide greater insights into these deep-branching eukaryotic pathogens.
Collapse
Affiliation(s)
- Ian M Lamb
- Center for Molecular Parasitology, Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA;
| | - Ijeoma C Okoye
- Center for Molecular Parasitology, Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA;
| | - Michael W Mather
- Center for Molecular Parasitology, Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA;
| | - Akhil B Vaidya
- Center for Molecular Parasitology, Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA;
| |
Collapse
|
5
|
Sinha SD, Wideman JG. The persistent homology of mitochondrial ATP synthases. iScience 2023; 26:106700. [PMID: 37250340 PMCID: PMC10214729 DOI: 10.1016/j.isci.2023.106700] [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: 09/30/2022] [Revised: 01/24/2023] [Accepted: 04/14/2023] [Indexed: 05/31/2023] Open
Abstract
Relatively little is known about ATP synthase structure in protists, and the investigated ones exhibit divergent structures distinct from yeast or animals. To clarify the subunit composition of ATP synthases across all eukaryotic lineages, we used homology detection techniques and molecular modeling tools to identify an ancestral set of 17 ATP synthase subunits. Most eukaryotes possess an ATP synthase comparable to those of animals and fungi, while some have undergone drastic divergence (e.g., ciliates, myzozoans, euglenozoans). Additionally, a ∼1 billion-year-old gene fusion between ATP synthase stator subunits was identified as a synapomorphy of the SAR (Stramenopila, Alveolata, Rhizaria) supergroup (stramenopile, alveolate, rhizaria). Our comparative approach highlights the persistence of ancestral subunits even amidst major structural changes. We conclude by urging that more ATP synthase structures (e.g., from jakobids, heteroloboseans, stramenopiles, rhizarians) are needed to provide a complete picture of the evolution of the structural diversity of this ancient and essential complex.
Collapse
Affiliation(s)
- Savar D. Sinha
- Center for Mechanisms of Evolution, Biodesign Institute, School of Life Sciences, Arizona State University, Tempe, AZ 85281, USA
| | - Jeremy G. Wideman
- Center for Mechanisms of Evolution, Biodesign Institute, School of Life Sciences, Arizona State University, Tempe, AZ 85281, USA
| |
Collapse
|
6
|
Maclean AE, Hayward JA, Huet D, van Dooren GG, Sheiner L. The mystery of massive mitochondrial complexes: the apicomplexan respiratory chain. Trends Parasitol 2022; 38:1041-1052. [PMID: 36302692 PMCID: PMC10434753 DOI: 10.1016/j.pt.2022.09.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 09/21/2022] [Accepted: 09/23/2022] [Indexed: 11/05/2022]
Abstract
The mitochondrial respiratory chain is an essential pathway in most studied eukaryotes due to its roles in respiration and other pathways that depend on mitochondrial membrane potential. Apicomplexans are unicellular eukaryotes whose members have an impact on global health. The respiratory chain is a drug target for some members of this group, notably the malaria-causing Plasmodium spp. This has motivated studies of the respiratory chain in apicomplexan parasites, primarily Toxoplasma gondii and Plasmodium spp. for which experimental tools are most advanced. Studies of the respiratory complexes in these organisms revealed numerous novel features, including expansion of complex size. The divergence of apicomplexan mitochondria from commonly studied models highlights the diversity of mitochondrial form and function across eukaryotic life.
Collapse
Affiliation(s)
- Andrew E Maclean
- Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, UK
| | - Jenni A Hayward
- Research School of Biology, Australian National University, Canberra, Australia
| | - Diego Huet
- Center for Tropical & Emerging Diseases, University of Georgia, Athens, GA, USA; Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens, GA, USA
| | - Giel G van Dooren
- Research School of Biology, Australian National University, Canberra, Australia
| | - Lilach Sheiner
- Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, UK.
| |
Collapse
|
7
|
Herneisen AL, Li ZH, Chan AW, Moreno SNJ, Lourido S. Temporal and thermal profiling of the Toxoplasma proteome implicates parasite Protein Phosphatase 1 in the regulation of Ca 2+-responsive pathways. eLife 2022; 11:80336. [PMID: 35976251 PMCID: PMC9436416 DOI: 10.7554/elife.80336] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 08/17/2022] [Indexed: 11/13/2022] Open
Abstract
Apicomplexan parasites cause persistent mortality and morbidity worldwide through diseases including malaria, toxoplasmosis, and cryptosporidiosis. Ca2+ signaling pathways have been repurposed in these eukaryotic pathogens to regulate parasite-specific cellular processes governing the replicative and lytic phases of the infectious cycle, as well as the transition between them. Despite the presence of conserved Ca2+-responsive proteins, little is known about how specific signaling elements interact to impact pathogenesis. We mapped the Ca2+-responsive proteome of the model apicomplexan T. gondii via time-resolved phosphoproteomics and thermal proteome profiling. The waves of phosphoregulation following PKG activation and stimulated Ca2+ release corroborate known physiological changes but identify specific proteins operating in these pathways. Thermal profiling of parasite extracts identified many expected Ca2+-responsive proteins, such as parasite Ca2+-dependent protein kinases. Our approach also identified numerous Ca2+-responsive proteins that are not predicted to bind Ca2+, yet are critical components of the parasite signaling network. We characterized protein phosphatase 1 (PP1) as a Ca2+-responsive enzyme that relocalized to the parasite apex upon Ca2+ store release. Conditional depletion of PP1 revealed that the phosphatase regulates Ca2+ uptake to promote parasite motility. PP1 may thus be partly responsible for Ca2+-regulated serine/threonine phosphatase activity in apicomplexan parasites.
Collapse
Affiliation(s)
- Alice L Herneisen
- Whitehead Institute for Biomedical Research, Cambridge, United States
| | - Zhu-Hong Li
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, United States
| | - Alex W Chan
- Whitehead Institute for Biomedical Research, Cambridge, United States
| | - Silvia N J Moreno
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, United States
| | - Sebastian Lourido
- Whitehead Institute for Biomedical Research, Cambridge, United States
| |
Collapse
|
8
|
Identification and Validation of Toxoplasma gondii Mitoribosomal Large Subunit Components. Microorganisms 2022; 10:microorganisms10050863. [PMID: 35630308 PMCID: PMC9145746 DOI: 10.3390/microorganisms10050863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 04/04/2022] [Accepted: 04/05/2022] [Indexed: 12/10/2022] Open
Abstract
Mitochondrial ribosomes are fundamental to mitochondrial function, and thus survival, of nearly all eukaryotes. Despite their common ancestry, mitoribosomes have evolved divergent features in different eukaryotic lineages. In apicomplexans, the mitochondrial rRNA is extremely fragmented raising questions about its evolution, protein composition and structure. Apicomplexan mitochondrial translation and the mitoribosomes are essential in all parasites and life stages studied, highlighting mitoribosomes as a promising target for drugs. Still, the apicomplexan mitoribosome is understudied, with one of the obstacles being that its composition is unknown. Here, to facilitate the study of apicomplexan mitoribosomes, we identified and validated components of the mitoribosomal large subunit in the model apicomplexan Toxoplasma gondii.
Collapse
|
9
|
Hayward JA, Rajendran E, Makota FV, Bassett BJ, Devoy M, Neeman T, van Dooren GG. Real-Time Analysis of Mitochondrial Electron Transport Chain Function in Toxoplasma gondii Parasites Using a Seahorse XFe96 Extracellular Flux Analyzer. Bio Protoc 2022; 12:e4288. [PMID: 35118179 PMCID: PMC8769764 DOI: 10.21769/bioprotoc.4288] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 11/04/2021] [Accepted: 11/07/2021] [Indexed: 07/22/2023] Open
Abstract
The mitochondrial electron transport chain (ETC) performs several critical biological functions, including maintaining mitochondrial membrane potential, serving as an electron sink for important metabolic pathways, and contributing to the generation of ATP via oxidative phosphorylation. The ETC is important for the survival of many eukaryotic organisms, including intracellular parasites such as the apicomplexan Toxoplasma gondii. The ETC of T. gondii and related parasites differs in several ways from the ETC of the mammalian host cells they infect, and can be targeted by anti-parasitic drugs, including the clinically used compound atovaquone. To characterize the function of novel ETC proteins found in the parasite and to identify new ETC inhibitors, a scalable assay that assesses both ETC function and non-mitochondrial parasite metabolism (e.g., glycolysis) is desirable. Here, we describe methods to measure the oxygen consumption rate (OCR) of intact T. gondii parasites and thereby assess ETC function, while simultaneously measuring the extracellular acidification rate (ECAR) as a measure of general parasite metabolism, using a Seahorse XFe96 extracellular flux analyzer. We also describe a method to pinpoint the location of ETC defects and/or the targets of inhibitors, using permeabilized T. gondii parasites. We have successfully used these methods to investigate the function of T. gondii proteins, including the apicomplexan parasite-specific protein subunit TgQCR11 of the coenzyme Q:cytochrome c oxidoreductase complex (ETC Complex III). We note that these methods are also amenable to screening compound libraries to identify candidate ETC inhibitors.
Collapse
Affiliation(s)
- Jenni A. Hayward
- Research School of Biology, Australian National University, Canberra, Australia
| | - Esther Rajendran
- Research School of Biology, Australian National University, Canberra, Australia
| | - F. Victor Makota
- Research School of Biology, Australian National University, Canberra, Australia
| | - Brad J. Bassett
- Research School of Biology, Australian National University, Canberra, Australia
| | - Michael Devoy
- Flow Cytometry Facility, The John Curtin School of Medical Research, Australian National University, Canberra, Australia
| | - Teresa Neeman
- Biological Data Science Institute, The Australian National University, Canberra, Australia
| | - Giel G. van Dooren
- Research School of Biology, Australian National University, Canberra, Australia
| |
Collapse
|
10
|
Usey MM, Huet D. Parasite powerhouse: A review of the Toxoplasma gondii mitochondrion. J Eukaryot Microbiol 2022; 69:e12906. [PMID: 35315174 PMCID: PMC9490983 DOI: 10.1111/jeu.12906] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Toxoplasma gondii is a member of the apicomplexan phylum, a group of single-celled eukaryotic parasites that cause significant human morbidity and mortality around the world. T. gondii harbors two organelles of endosymbiotic origin: a non-photosynthetic plastid, known as the apicoplast, and a single mitochondrion derived from the ancient engulfment of an α-proteobacterium. Due to excitement surrounding the novelty of the apicoplast, the T. gondii mitochondrion was, to a certain extent, overlooked for about two decades. However, recent work has illustrated that the mitochondrion is an essential hub of apicomplexan-specific biology. Development of novel techniques, such as cryo-electron microscopy, complexome profiling, and next-generation sequencing have led to a renaissance in mitochondrial studies. This review will cover what is currently known about key features of the T. gondii mitochondrion, ranging from its genome to protein import machinery and biochemical pathways. Particular focus will be given to mitochondrial features that diverge significantly from the mammalian host, along with discussion of this important organelle as a drug target.
Collapse
Affiliation(s)
- Madelaine M. Usey
- Department of Cellular BiologyUniversity of GeorgiaAthensGeorgiaUSA,Center for Tropical and Emerging Global DiseasesUniversity of GeorgiaAthensGeorgiaUSA
| | - Diego Huet
- Center for Tropical and Emerging Global DiseasesUniversity of GeorgiaAthensGeorgiaUSA,Department of Pharmaceutical and Biomedical SciencesUniversity of GeorgiaAthensGeorgiaUSA
| |
Collapse
|
11
|
Berná L, Rego N, Francia ME. The Elusive Mitochondrial Genomes of Apicomplexa: Where Are We Now? Front Microbiol 2021; 12:751775. [PMID: 34721355 PMCID: PMC8554336 DOI: 10.3389/fmicb.2021.751775] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 09/16/2021] [Indexed: 11/16/2022] Open
Abstract
Mitochondria are vital organelles of eukaryotic cells, participating in key metabolic pathways such as cellular respiration, thermogenesis, maintenance of cellular redox potential, calcium homeostasis, cell signaling, and cell death. The phylum Apicomplexa is entirely composed of obligate intracellular parasites, causing a plethora of severe diseases in humans, wild and domestic animals. These pathogens include the causative agents of malaria, cryptosporidiosis, neosporosis, East Coast fever and toxoplasmosis, among others. The mitochondria in Apicomplexa has been put forward as a promising source of undiscovered drug targets, and it has been validated as the target of atovaquone, a drug currently used in the clinic to counter malaria. Apicomplexans present a single tubular mitochondria that varies widely both in structure and in genomic content across the phylum. The organelle is characterized by massive gene migrations to the nucleus, sequence rearrangements and drastic functional reductions in some species. Recent third generation sequencing studies have reignited an interest for elucidating the extensive diversity displayed by the mitochondrial genomes of apicomplexans and their intriguing genomic features. The underlying mechanisms of gene transcription and translation are also ill-understood. In this review, we present the state of the art on mitochondrial genome structure, composition and organization in the apicomplexan phylum revisiting topological and biochemical information gathered through classical techniques. We contextualize this in light of the genomic insight gained by second and, more recently, third generation sequencing technologies. We discuss the mitochondrial genomic and mechanistic features found in evolutionarily related alveolates, and discuss the common and distinct origins of the apicomplexan mitochondria peculiarities.
Collapse
Affiliation(s)
- Luisa Berná
- Laboratory of Apicomplexan Biology, Institut Pasteur de Montevideo, Montevideo, Uruguay.,Molecular Biology Unit, Institut Pasteur de Montevideo, Montevideo, Uruguay.,Bioinformatics Unit, Institut Pasteur de Montevideo, Montevideo, Uruguay.,Sección Biomatemática-Laboratorio de Genómica Evolutiva, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Natalia Rego
- Bioinformatics Unit, Institut Pasteur de Montevideo, Montevideo, Uruguay
| | - María E Francia
- Laboratory of Apicomplexan Biology, Institut Pasteur de Montevideo, Montevideo, Uruguay.,Departamento de Parasitología y Micología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| |
Collapse
|
12
|
Gahura O, Hierro-Yap C, Zíková A. Redesigned and reversed: architectural and functional oddities of the trypanosomal ATP synthase. Parasitology 2021; 148:1151-1160. [PMID: 33551002 PMCID: PMC8311965 DOI: 10.1017/s0031182021000202] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Revised: 01/23/2021] [Accepted: 01/26/2021] [Indexed: 12/23/2022]
Abstract
Mitochondrial F-type adenosine triphosphate (ATP) synthases are commonly introduced as highly conserved membrane-embedded rotary machines generating the majority of cellular ATP. This simplified view neglects recently revealed striking compositional diversity of the enzyme and the fact that in specific life stages of some parasites, the physiological role of the enzyme is to maintain the mitochondrial membrane potential at the expense of ATP rather than to produce ATP. In addition, mitochondrial ATP synthases contribute indirectly to the organelle's other functions because they belong to major determinants of submitochondrial morphology. Here, we review current knowledge about the trypanosomal ATP synthase composition and architecture in the context of recent advances in the structural characterization of counterpart enzymes from several eukaryotic supergroups. We also discuss the physiological function of mitochondrial ATP synthases in three trypanosomatid parasites, Trypanosoma cruzi, Trypanosoma brucei and Leishmania, with a focus on their disease-causing life cycle stages. We highlight the reversed proton-pumping role of the ATP synthase in the T. brucei bloodstream form, the enzyme's potential link to the regulation of parasite's glycolysis and its role in generating mitochondrial membrane potential in the absence of mitochondrial DNA.
Collapse
Affiliation(s)
- Ondřej Gahura
- Biology Centre, Czech Academy of Sciences, Branišovská 31, České Budějovice, 37005, Czech Republic
| | - Carolina Hierro-Yap
- Biology Centre, Czech Academy of Sciences, Branišovská 31, České Budějovice, 37005, Czech Republic
- Faculty of Science, University of South Bohemia, Branišovská 31, České Budějovice, 37005, Czech Republic
| | - Alena Zíková
- Biology Centre, Czech Academy of Sciences, Branišovská 31, České Budějovice, 37005, Czech Republic
- Faculty of Science, University of South Bohemia, Branišovská 31, České Budějovice, 37005, Czech Republic
| |
Collapse
|
13
|
Evers F, Cabrera-Orefice A, Elurbe DM, Kea-Te Lindert M, Boltryk SD, Voss TS, Huynen MA, Brandt U, Kooij TWA. Composition and stage dynamics of mitochondrial complexes in Plasmodium falciparum. Nat Commun 2021; 12:3820. [PMID: 34155201 PMCID: PMC8217502 DOI: 10.1038/s41467-021-23919-x] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 05/21/2021] [Indexed: 12/19/2022] Open
Abstract
Our current understanding of mitochondrial functioning is largely restricted to traditional model organisms, which only represent a fraction of eukaryotic diversity. The unusual mitochondrion of malaria parasites is a validated drug target but remains poorly understood. Here, we apply complexome profiling to map the inventory of protein complexes across the pathogenic asexual blood stages and the transmissible gametocyte stages of Plasmodium falciparum. We identify remarkably divergent composition and clade-specific additions of all respiratory chain complexes. Furthermore, we show that respiratory chain complex components and linked metabolic pathways are up to 40-fold more prevalent in gametocytes, while glycolytic enzymes are substantially reduced. Underlining this functional switch, we find that cristae are exclusively present in gametocytes. Leveraging these divergent properties and stage dynamics for drug development presents an attractive opportunity to discover novel classes of antimalarials and increase our repertoire of gametocytocidal drugs.
Collapse
Affiliation(s)
- Felix Evers
- Department of Medical Microbiology, Radboudumc Center for Infectious Diseases, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Alfredo Cabrera-Orefice
- Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
- Centre for Molecular and Biomolecular Informatics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Dei M Elurbe
- Centre for Molecular and Biomolecular Informatics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Mariska Kea-Te Lindert
- Electron Microscopy Center, RTC Microscopy, Radboud Institute of Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
- Department of Cell Biology, Radboud Institute of Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Sylwia D Boltryk
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Till S Voss
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Martijn A Huynen
- Centre for Molecular and Biomolecular Informatics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Ulrich Brandt
- Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Taco W A Kooij
- Department of Medical Microbiology, Radboudumc Center for Infectious Diseases, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands.
| |
Collapse
|
14
|
Mathur V, Wakeman KC, Keeling PJ. Parallel functional reduction in the mitochondria of apicomplexan parasites. Curr Biol 2021; 31:2920-2928.e4. [PMID: 33974849 DOI: 10.1016/j.cub.2021.04.028] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 02/18/2021] [Accepted: 04/12/2021] [Indexed: 12/20/2022]
Abstract
Gregarines are an early-diverging lineage of apicomplexan parasites that hold many clues into the origin and evolution of the group, a remarkable transition from free-living phototrophic algae into obligate parasites of animals.1 Using single-cell transcriptomics targeting understudied lineages to complement available sequencing data, we characterized the mitochondrial metabolic repertoire across the tree of apicomplexans. In contrast to the large suite of proteins involved in aerobic respiration in well-studied parasites like Toxoplasma or Plasmodium,2 we find that gregarine trophozoites have significantly reduced energy metabolism: most lack respiratory complexes III and IV, and some lack the electron transport chains (ETCs) and tricarboxylic acid (TCA) cycle entirely. Phylogenomic analyses show that these reductions took place several times in parallel, resulting in a functional range from fully aerobic organelles to extremely reduced "mitosomes" restricted to Fe-S cluster biosynthesis. The mitochondrial genome has also been lost repeatedly: in species with severe functional reduction simply by gene loss but in one species with a complete ETC by relocating cox1 to the nuclear genome. Severe functional reduction of mitochondria is generally associated with structural reduction, resulting in small, nondescript mitochondrial-related organelles (MROs).3 By contrast, gregarines retain distinctive mitochondria with tubular cristae, even the most functionally reduced cases that also lack genes associated with cristae formation. Overall, the parallel, severe reduction of gregarine mitochondria expands the diversity of organisms that contain MROs and further emphasizes the role of parallel transitions in apicomplexan evolution.
Collapse
Affiliation(s)
- Varsha Mathur
- Department of Botany, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
| | - Kevin C Wakeman
- Institute for the Advancement of Higher Education, Hokkaido University, Sapporo 060-0810, Hokkaido, Japan
| | - Patrick J Keeling
- Department of Botany, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
| |
Collapse
|
15
|
Berná L, Marquez P, Cabrera A, Greif G, Francia ME, Robello C. Reevaluation of the Toxoplasma gondii and Neospora caninum genomes reveals misassembly, karyotype differences, and chromosomal rearrangements. Genome Res 2021; 31:823-833. [PMID: 33906964 PMCID: PMC8092007 DOI: 10.1101/gr.262832.120] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 12/16/2020] [Indexed: 12/14/2022]
Abstract
Neosporacaninum primarily infects cattle, causing abortions, with an estimated impact of a billion dollars on the worldwide economy annually. However, the study of its biology has been unheeded by the established paradigm that it is virtually identical to its close relative, the widely studied human pathogen Toxoplasma gondii. By revisiting the genome sequence, assembly, and annotation using third-generation sequencing technologies, here we show that the N. caninum genome was originally incorrectly assembled under the presumption of synteny with T. gondii. We show that major chromosomal rearrangements have occurred between these species. Importantly, we show that chromosomes originally named Chr VIIb and VIII are indeed fused, reducing the karyotype of both N. caninum and T. gondii to 13 chromosomes. We reannotate the N. caninum genome, revealing more than 500 new genes. We sequence and annotate the nonphotosynthetic plastid and mitochondrial genomes and show that although apicoplast genomes are virtually identical, high levels of gene fragmentation and reshuffling exist between species and strains. Our results correct assembly artifacts that are currently widely distributed in the genome database of N. caninum and T. gondii and, more importantly, highlight the mitochondria as a previously oversighted source of variability and pave the way for a change in the paradigm of synteny, encouraging rethinking the genome as basis of the comparative unique biology of these pathogens.
Collapse
Affiliation(s)
- Luisa Berná
- Laboratory of Host Pathogen Interactions-Molecular Biology Unit, Institut Pasteur de Montevideo, 11400 Montevideo, Uruguay
| | - Pablo Marquez
- Laboratory of Host Pathogen Interactions-Molecular Biology Unit, Institut Pasteur de Montevideo, 11400 Montevideo, Uruguay
| | - Andrés Cabrera
- Laboratory of Host Pathogen Interactions-Molecular Biology Unit, Institut Pasteur de Montevideo, 11400 Montevideo, Uruguay
| | - Gonzalo Greif
- Laboratory of Host Pathogen Interactions-Molecular Biology Unit, Institut Pasteur de Montevideo, 11400 Montevideo, Uruguay
| | - María E Francia
- Laboratory of Apicomplexan Biology, Institut Pasteur de Montevideo, 11400 Montevideo, Uruguay.,Departamento de Parasitología y Micología, Facultad de Medicina-Universidad de la República, 11600 Montevideo, Uruguay
| | - Carlos Robello
- Laboratory of Host Pathogen Interactions-Molecular Biology Unit, Institut Pasteur de Montevideo, 11400 Montevideo, Uruguay.,Departamento de Bioquímica, Facultad de Medicina-Universidad de la República, 11300 Montevideo, Uruguay
| |
Collapse
|
16
|
Salomaki ED, Terpis KX, Rueckert S, Kotyk M, Varadínová ZK, Čepička I, Lane CE, Kolisko M. Gregarine single-cell transcriptomics reveals differential mitochondrial remodeling and adaptation in apicomplexans. BMC Biol 2021; 19:77. [PMID: 33863338 PMCID: PMC8051059 DOI: 10.1186/s12915-021-01007-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 03/19/2021] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Apicomplexa is a diverse phylum comprising unicellular endobiotic animal parasites and contains some of the most well-studied microbial eukaryotes including the devastating human pathogens Plasmodium falciparum and Cryptosporidium hominis. In contrast, data on the invertebrate-infecting gregarines remains sparse and their evolutionary relationship to other apicomplexans remains obscure. Most apicomplexans retain a highly modified plastid, while their mitochondria remain metabolically conserved. Cryptosporidium spp. inhabit an anaerobic host-gut environment and represent the known exception, having completely lost their plastid while retaining an extremely reduced mitochondrion that has lost its genome. Recent advances in single-cell sequencing have enabled the first broad genome-scale explorations of gregarines, providing evidence of differential plastid retention throughout the group. However, little is known about the retention and metabolic capacity of gregarine mitochondria. RESULTS Here, we sequenced transcriptomes from five species of gregarines isolated from cockroaches. We combined these data with those from other apicomplexans, performed detailed phylogenomic analyses, and characterized their mitochondrial metabolism. Our results support the placement of Cryptosporidium as the earliest diverging lineage of apicomplexans, which impacts our interpretation of evolutionary events within the phylum. By mapping in silico predictions of core mitochondrial pathways onto our phylogeny, we identified convergently reduced mitochondria. These data show that the electron transport chain has been independently lost three times across the phylum, twice within gregarines. CONCLUSIONS Apicomplexan lineages show variable functional restructuring of mitochondrial metabolism that appears to have been driven by adaptations to parasitism and anaerobiosis. Our findings indicate that apicomplexans are rife with convergent adaptations, with shared features including morphology, energy metabolism, and intracellularity.
Collapse
Affiliation(s)
- Eric D Salomaki
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Kristina X Terpis
- Department of Biological Sciences, University of Rhode Island, Kingston, RI, USA
| | - Sonja Rueckert
- School of Applied Sciences, Edinburgh Napier University, Edinburgh, Scotland, UK
| | - Michael Kotyk
- Department of Zoology, Faculty of Science, Charles University in Prague, Prague, Czech Republic
| | | | - Ivan Čepička
- Department of Zoology, Faculty of Science, Charles University in Prague, Prague, Czech Republic
| | - Christopher E Lane
- Department of Biological Sciences, University of Rhode Island, Kingston, RI, USA.
| | - Martin Kolisko
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic.
- Department of Molecular Biology and Genetics, University of South Bohemia, České Budějovice, Czech Republic.
| |
Collapse
|
17
|
Comparative proteomic profiling of newly acquired, virulent and attenuated Neoparamoeba perurans proteins associated with amoebic gill disease. Sci Rep 2021; 11:6830. [PMID: 33767232 PMCID: PMC7994405 DOI: 10.1038/s41598-021-85988-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 03/02/2021] [Indexed: 12/25/2022] Open
Abstract
The causative agent of amoebic gill disease, Neoparamoeba perurans is reported to lose virulence during prolonged in vitro maintenance. In this study, the impact of prolonged culture on N. perurans virulence and its proteome was investigated. Two isolates, attenuated and virulent, had their virulence assessed in an experimental trial using Atlantic salmon smolts and their bacterial community composition was evaluated by 16S rRNA Illumina MiSeq sequencing. Soluble proteins were isolated from three isolates: a newly acquired, virulent and attenuated N. perurans culture. Proteins were analysed using two-dimensional electrophoresis coupled with liquid chromatography tandem mass spectrometry (LC-MS/MS). The challenge trial using naïve smolts confirmed a loss in virulence in the attenuated N. perurans culture. A greater diversity of bacterial communities was found in the microbiome of the virulent isolate in contrast to a reduction in microbial community richness in the attenuated microbiome. A collated proteome database of N. perurans, Amoebozoa and four bacterial genera resulted in 24 proteins differentially expressed between the three cultures. The present LC-MS/MS results indicate protein synthesis, oxidative stress and immunomodulation are upregulated in a newly acquired N. perurans culture and future studies may exploit these protein identifications for therapeutic purposes in infected farmed fish.
Collapse
|
18
|
Maclean AE, Bridges HR, Silva MF, Ding S, Ovciarikova J, Hirst J, Sheiner L. Complexome profile of Toxoplasma gondii mitochondria identifies divergent subunits of respiratory chain complexes including new subunits of cytochrome bc1 complex. PLoS Pathog 2021; 17:e1009301. [PMID: 33651838 PMCID: PMC7987180 DOI: 10.1371/journal.ppat.1009301] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 03/23/2021] [Accepted: 01/11/2021] [Indexed: 12/30/2022] Open
Abstract
The mitochondrial electron transport chain (mETC) and F1Fo-ATP synthase are of central importance for energy and metabolism in eukaryotic cells. The Apicomplexa, important pathogens of humans causing diseases such as toxoplasmosis and malaria, depend on their mETC in every known stage of their complicated life cycles. Here, using a complexome profiling proteomic approach, we have characterised the Toxoplasma mETC complexes and F1Fo-ATP synthase. We identified and assigned 60 proteins to complexes II, IV and F1Fo-ATP synthase of Toxoplasma, of which 16 have not been identified previously. Notably, our complexome profile elucidates the composition of the Toxoplasma complex III, the target of clinically used drugs such as atovaquone. We identified two new homologous subunits and two new parasite-specific subunits, one of which is broadly conserved in myzozoans. We demonstrate all four proteins are essential for complex III stability and parasite growth, and show their depletion leads to decreased mitochondrial potential, supporting their assignment as complex III subunits. Our study highlights the divergent subunit composition of the apicomplexan mETC and F1Fo-ATP synthase complexes and sets the stage for future structural and drug discovery studies.
Collapse
Affiliation(s)
- Andrew E. Maclean
- Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, United Kingdom
| | - Hannah R. Bridges
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge, United Kingdom
| | - Mariana F. Silva
- Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, United Kingdom
- Institute of Biomedical Sciences, Federal University of Uberlândia, Uberlândia, Brazil
| | - Shujing Ding
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge, United Kingdom
| | - Jana Ovciarikova
- Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, United Kingdom
| | - Judy Hirst
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge, United Kingdom
| | - Lilach Sheiner
- Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, United Kingdom
| |
Collapse
|
19
|
Miranda-Astudillo HV, Yadav KNS, Boekema EJ, Cardol P. Supramolecular associations between atypical oxidative phosphorylation complexes of Euglena gracilis. J Bioenerg Biomembr 2021; 53:351-363. [PMID: 33646522 PMCID: PMC8124061 DOI: 10.1007/s10863-021-09882-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 02/11/2021] [Indexed: 11/28/2022]
Abstract
In vivo associations of respiratory complexes forming higher supramolecular structures are generally accepted nowadays. Supercomplexes (SC) built by complexes I, III and IV and the so-called respirasome (I/III2/IV) have been described in mitochondria from several model organisms (yeasts, mammals and green plants), but information is scarce in other lineages. Here we studied the supramolecular associations between the complexes I, III, IV and V from the secondary photosynthetic flagellate Euglena gracilis with an approach that involves the extraction with several mild detergents followed by native electrophoresis. Despite the presence of atypical subunit composition and additional structural domains described in Euglena complexes I, IV and V, canonical associations into III2/IV, III2/IV2 SCs and I/III2/IV respirasome were observed together with two oligomeric forms of the ATP synthase (V2 and V4). Among them, III2/IV SC could be observed by electron microscopy. The respirasome was further purified by two-step liquid chromatography and showed in-vitro oxygen consumption independent of the addition of external cytochrome c.
Collapse
Affiliation(s)
- H V Miranda-Astudillo
- InBios/Phytosystems, Institut de Botanique, University of Liège, Liège, Belgium.
- Departamento de Biología Molecular y Biotecnología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Mexico City, Mexico.
| | - K N S Yadav
- Department of Electron Microscopy, Groningen Biological Sciences and Biotechnology Institute, University of Groningen, Groningen, the Netherlands
- School of Biochemistry, University of Bristol, Bristol, BS8 1TD, UK
| | - E J Boekema
- Department of Electron Microscopy, Groningen Biological Sciences and Biotechnology Institute, University of Groningen, Groningen, the Netherlands
| | - P Cardol
- InBios/Phytosystems, Institut de Botanique, University of Liège, Liège, Belgium.
| |
Collapse
|
20
|
Hierro-Yap C, Šubrtová K, Gahura O, Panicucci B, Dewar C, Chinopoulos C, Schnaufer A, Zíková A. Bioenergetic consequences of F oF 1-ATP synthase/ATPase deficiency in two life cycle stages of Trypanosoma brucei. J Biol Chem 2021; 296:100357. [PMID: 33539923 PMCID: PMC7949148 DOI: 10.1016/j.jbc.2021.100357] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 12/23/2020] [Accepted: 01/28/2021] [Indexed: 12/17/2022] Open
Abstract
Mitochondrial ATP synthase is a reversible nanomotor synthesizing or hydrolyzing ATP depending on the potential across the membrane in which it is embedded. In the unicellular parasite Trypanosoma brucei, the direction of the complex depends on the life cycle stage of this digenetic parasite: in the midgut of the tsetse fly vector (procyclic form), the FoF1–ATP synthase generates ATP by oxidative phosphorylation, whereas in the mammalian bloodstream form, this complex hydrolyzes ATP and maintains mitochondrial membrane potential (ΔΨm). The trypanosome FoF1–ATP synthase contains numerous lineage-specific subunits whose roles remain unknown. Here, we seek to elucidate the function of the lineage-specific protein Tb1, the largest membrane-bound subunit. In procyclic form cells, Tb1 silencing resulted in a decrease of FoF1–ATP synthase monomers and dimers, rerouting of mitochondrial electron transfer to the alternative oxidase, reduced growth rate and cellular ATP levels, and elevated ΔΨm and total cellular reactive oxygen species levels. In bloodstream form parasites, RNAi silencing of Tb1 by ∼90% resulted in decreased FoF1–ATPase monomers and dimers, but it had no apparent effect on growth. The same findings were obtained by silencing of the oligomycin sensitivity-conferring protein, a conserved subunit in T. brucei FoF1–ATP synthase. However, as expected, nearly complete Tb1 or oligomycin sensitivity-conferring protein suppression was lethal because of the inability to sustain ΔΨm. The diminishment of FoF1–ATPase complexes was further accompanied by a decreased ADP/ATP ratio and reduced oxygen consumption via the alternative oxidase. Our data illuminate the often diametrically opposed bioenergetic consequences of FoF1–ATP synthase loss in insect versus mammalian forms of the parasite.
Collapse
Affiliation(s)
- Carolina Hierro-Yap
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Ceske Budejovice, Czech Republic; Faculty of Science, University of South Bohemia, Ceske Budejovice, Czech Republic
| | - Karolína Šubrtová
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Ceske Budejovice, Czech Republic; Institute of Immunology and Infection Research, University of Edinburgh, United Kingdom
| | - Ondřej Gahura
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Ceske Budejovice, Czech Republic
| | - Brian Panicucci
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Ceske Budejovice, Czech Republic
| | - Caroline Dewar
- Institute of Immunology and Infection Research, University of Edinburgh, United Kingdom
| | | | - Achim Schnaufer
- Institute of Immunology and Infection Research, University of Edinburgh, United Kingdom
| | - Alena Zíková
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Ceske Budejovice, Czech Republic; Faculty of Science, University of South Bohemia, Ceske Budejovice, Czech Republic.
| |
Collapse
|
21
|
Hayward JA, Rajendran E, Zwahlen SM, Faou P, van Dooren GG. Divergent features of the coenzyme Q:cytochrome c oxidoreductase complex in Toxoplasma gondii parasites. PLoS Pathog 2021; 17:e1009211. [PMID: 33524071 PMCID: PMC7877769 DOI: 10.1371/journal.ppat.1009211] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 02/11/2021] [Accepted: 12/03/2020] [Indexed: 11/19/2022] Open
Abstract
The mitochondrion is critical for the survival of apicomplexan parasites. Several major anti-parasitic drugs, such as atovaquone and endochin-like quinolones, act through inhibition of the mitochondrial electron transport chain at the coenzyme Q:cytochrome c oxidoreductase complex (Complex III). Despite being an important drug target, the protein composition of Complex III of apicomplexan parasites has not been elucidated. Here, we undertake a mass spectrometry-based proteomic analysis of Complex III in the apicomplexan Toxoplasma gondii. Along with canonical subunits that are conserved across eukaryotic evolution, we identify several novel or highly divergent Complex III components that are conserved within the apicomplexan lineage. We demonstrate that one such subunit, which we term TgQCR11, is critical for parasite proliferation, mitochondrial oxygen consumption and Complex III activity, and establish that loss of this protein leads to defects in Complex III integrity. We conclude that the protein composition of Complex III in apicomplexans differs from that of the mammalian hosts that these parasites infect.
Collapse
Affiliation(s)
- Jenni A. Hayward
- Research School of Biology, Australian National University, Canberra, Australia
| | - Esther Rajendran
- Research School of Biology, Australian National University, Canberra, Australia
| | - Soraya M. Zwahlen
- Research School of Biology, Australian National University, Canberra, Australia
| | - Pierre Faou
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Australia
| | - Giel G. van Dooren
- Research School of Biology, Australian National University, Canberra, Australia
| |
Collapse
|
22
|
Mühleip A, Kock Flygaard R, Ovciarikova J, Lacombe A, Fernandes P, Sheiner L, Amunts A. ATP synthase hexamer assemblies shape cristae of Toxoplasma mitochondria. Nat Commun 2021; 12:120. [PMID: 33402698 PMCID: PMC7785744 DOI: 10.1038/s41467-020-20381-z] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 11/30/2020] [Indexed: 01/29/2023] Open
Abstract
Mitochondrial ATP synthase plays a key role in inducing membrane curvature to establish cristae. In Apicomplexa causing diseases such as malaria and toxoplasmosis, an unusual cristae morphology has been observed, but its structural basis is unknown. Here, we report that the apicomplexan ATP synthase assembles into cyclic hexamers, essential to shape their distinct cristae. Cryo-EM was used to determine the structure of the hexamer, which is held together by interactions between parasite-specific subunits in the lumenal region. Overall, we identified 17 apicomplexan-specific subunits, and a minimal and nuclear-encoded subunit-a. The hexamer consists of three dimers with an extensive dimer interface that includes bound cardiolipins and the inhibitor IF1. Cryo-ET and subtomogram averaging revealed that hexamers arrange into ~20-megadalton pentagonal pyramids in the curved apical membrane regions. Knockout of the linker protein ATPTG11 resulted in the loss of pentagonal pyramids with concomitant aberrantly shaped cristae. Together, this demonstrates that the unique macromolecular arrangement is critical for the maintenance of cristae morphology in Apicomplexa.
Collapse
Affiliation(s)
- Alexander Mühleip
- Science for Life Laboratory, Department of Biochemistry and Biophysics, Stockholm University, 17165, Solna, Sweden
- Department of Medical Biochemistry and Biophysics, Karolinska Institute, 17177, Stockholm, Sweden
| | - Rasmus Kock Flygaard
- Science for Life Laboratory, Department of Biochemistry and Biophysics, Stockholm University, 17165, Solna, Sweden
- Department of Medical Biochemistry and Biophysics, Karolinska Institute, 17177, Stockholm, Sweden
| | - Jana Ovciarikova
- Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, UK
| | - Alice Lacombe
- Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, UK
| | - Paula Fernandes
- Science for Life Laboratory, Department of Biochemistry and Biophysics, Stockholm University, 17165, Solna, Sweden
- Department of Medical Biochemistry and Biophysics, Karolinska Institute, 17177, Stockholm, Sweden
- Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, UK
| | - Lilach Sheiner
- Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, UK.
| | - Alexey Amunts
- Science for Life Laboratory, Department of Biochemistry and Biophysics, Stockholm University, 17165, Solna, Sweden.
- Department of Medical Biochemistry and Biophysics, Karolinska Institute, 17177, Stockholm, Sweden.
| |
Collapse
|
23
|
Prasad A, Mastud P, Patankar S. Dually localised proteins found in both the apicoplast and mitochondrion utilize the Golgi-dependent pathway for apicoplast targeting in Toxoplasma gondii. Biol Cell 2020; 113:58-78. [PMID: 33112425 DOI: 10.1111/boc.202000050] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Accepted: 10/07/2020] [Indexed: 11/28/2022]
Abstract
BACKGROUND INFORMATION Like other apicomplexan parasites, Toxoplasma gondii harbours a four-membraned endosymbiotic organelle - the apicoplast. Apicoplast proteins are nuclear encoded and trafficked to the organelle through the endoplasmic reticulum (ER). From the ER to the apicoplast, two distinct protein trafficking pathways can be used. One such pathway is the cell's secretory pathway involving the Golgi, whereas the other is a unique Golgi-independent pathway. Using different experimental approaches, many apicoplast proteins have been shown to utilize the Golgi-independent pathway, whereas a handful of reports show that a few proteins use the Golgi-dependent pathway. This has led to an emphasis towards the unique Golgi-independent pathway when apicoplast protein trafficking is discussed in the literature. Additionally, the molecular features that drive proteins to each pathway are not known. RESULTS In this report, we systematically test eight apicoplast proteins, using a C-terminal HDEL sequence to assess the role of the Golgi in their transport. We demonstrate that dually localised proteins of the apicoplast and mitochondrion (TgSOD2, TgTPx1/2 and TgACN/IRP) are trafficked through the Golgi, whereas proteins localised exclusively to the apicoplast are trafficked independent of the Golgi. Mutants of the dually localised proteins that localised exclusively to the apicoplast also showed trafficking through the Golgi. Phylogenetic analysis of TgSOD2, TgTPx1/2 and TgACN/IRP suggested that the evolutionary origins of TgSOD2 and TgTPx1/2 lie in the mitochondrion, whereas TgACN/IRP appears to have originated from the apicoplast. CONCLUSIONS AND SIGNIFICANCE Collectively, with these results, for the first time, we establish that the driver of the Golgi-dependent trafficking route to the apicoplast is the dual localisation of the protein to the apicoplast and the mitochondrion.
Collapse
Affiliation(s)
- Aparna Prasad
- Department of Biosciences & Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
| | - Pragati Mastud
- Department of Biosciences & Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
| | - Swati Patankar
- Department of Biosciences & Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
| |
Collapse
|
24
|
Martin RE. The transportome of the malaria parasite. Biol Rev Camb Philos Soc 2019; 95:305-332. [PMID: 31701663 DOI: 10.1111/brv.12565] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Revised: 10/02/2019] [Accepted: 10/04/2019] [Indexed: 12/15/2022]
Abstract
Membrane transport proteins, also known as transporters, control the movement of ions, nutrients, metabolites, and waste products across the membranes of a cell and are central to its biology. Proteins of this type also serve as drug targets and are key players in the phenomenon of drug resistance. The malaria parasite has a relatively reduced transportome, with only approximately 2.5% of its genes encoding transporters. Even so, assigning functions and physiological roles to these proteins, and ascertaining their contributions to drug action and drug resistance, has been very challenging. This review presents a detailed critique and synthesis of the disruption phenotypes, protein subcellular localisations, protein functions (observed or predicted), and links to antimalarial drug resistance for each of the parasite's transporter genes. The breadth and depth of the gene disruption data are particularly impressive, with at least one phenotype determined in the parasite's asexual blood stage for each transporter gene, and multiple phenotypes available for 76% of the genes. Analysis of the curated data set revealed there to be relatively little redundancy in the Plasmodium transportome; almost two-thirds of the parasite's transporter genes are essential or required for normal growth in the asexual blood stage of the parasite, and this proportion increased to 78% when the disruption phenotypes available for the other parasite life stages were included in the analysis. These observations, together with the finding that 22% of the transportome is implicated in the parasite's resistance to existing antimalarials and/or drugs within the development pipeline, indicate that transporters are likely to serve, or are already serving, as drug targets. Integration of the different biological and bioinformatic data sets also enabled the selection of candidates for transport processes known to be essential for parasite survival, but for which the underlying proteins have thus far remained undiscovered. These include potential transporters of pantothenate, isoleucine, or isopentenyl diphosphate, as well as putative anion-selective channels that may serve as the pore component of the parasite's 'new permeation pathways'. Other novel insights into the parasite's biology included the identification of transporters for the potential development of antimalarial treatments, transmission-blocking drugs, prophylactics, and genetically attenuated vaccines. The syntheses presented herein set a foundation for elucidating the functions and physiological roles of key members of the Plasmodium transportome and, ultimately, to explore and realise their potential as therapeutic targets.
Collapse
Affiliation(s)
- Rowena E Martin
- Research School of Biology, Australian National University, Canberra, Australian Capital Territory, Australia
| |
Collapse
|
25
|
Same same, but different: Uncovering unique features of the mitochondrial respiratory chain of apicomplexans. Mol Biochem Parasitol 2019; 232:111204. [DOI: 10.1016/j.molbiopara.2019.111204] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2019] [Revised: 07/19/2019] [Accepted: 08/01/2019] [Indexed: 01/08/2023]
|
26
|
Lacombe A, Maclean AE, Ovciarikova J, Tottey J, Mühleip A, Fernandes P, Sheiner L. Identification of the
Toxoplasma gondii
mitochondrial ribosome, and characterisation of a protein essential for mitochondrial translation. Mol Microbiol 2019; 112:1235-1252. [PMID: 31339607 PMCID: PMC6851545 DOI: 10.1111/mmi.14357] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/21/2019] [Indexed: 01/20/2023]
Abstract
Apicomplexan parasites cause diseases such as malaria and toxoplasmosis. The apicomplexan mitochondrion shows striking differences from common model organisms, including fundamental processes such as mitochondrial translation. Despite evidence that mitochondrial translation is essential for parasite survival, it is largely understudied. Progress has been restricted by the absence of functional assays to detect apicomplexan mitochondrial translation, a lack of knowledge of proteins involved in the process and the inability to identify and detect mitoribosomes. We report the localization of 12 new mitochondrial proteins, including 6 putative mitoribosomal proteins. We demonstrate the integration of three mitoribosomal proteins in macromolecular complexes, and provide evidence suggesting these are apicomplexan mitoribosomal subunits, detected here for the first time. Finally, a new analytical pipeline detected defects in mitochondrial translation upon depletion of the small subunit protein 35 (TgmS35), while other mitochondrial functions remain unaffected. Our work lays a foundation for the study of apicomplexan mitochondrial translation.
Collapse
Affiliation(s)
- Alice Lacombe
- Wellcome Centre for Integrative Parasitology University of Glasgow 120 University Place GlasgowG12 8TAUK
| | - Andrew E. Maclean
- Wellcome Centre for Integrative Parasitology University of Glasgow 120 University Place GlasgowG12 8TAUK
| | - Jana Ovciarikova
- Wellcome Centre for Integrative Parasitology University of Glasgow 120 University Place GlasgowG12 8TAUK
| | - Julie Tottey
- Wellcome Centre for Integrative Parasitology University of Glasgow 120 University Place GlasgowG12 8TAUK
- UMR 1282 ISP INRA‐Université François Rabelais de Tours Nouzilly France
| | - Alexander Mühleip
- Department of Biochemistry and Biophysics Stockholm University Stockholm Sweden
| | - Paula Fernandes
- Wellcome Centre for Integrative Parasitology University of Glasgow 120 University Place GlasgowG12 8TAUK
| | - Lilach Sheiner
- Wellcome Centre for Integrative Parasitology University of Glasgow 120 University Place GlasgowG12 8TAUK
| |
Collapse
|
27
|
Mastud P, Patankar S. An ambiguous N-terminus drives the dual targeting of an antioxidant protein Thioredoxin peroxidase (TgTPx1/2) to endosymbiotic organelles in Toxoplasma gondii. PeerJ 2019; 7:e7215. [PMID: 31346496 PMCID: PMC6642795 DOI: 10.7717/peerj.7215] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Accepted: 05/30/2019] [Indexed: 12/21/2022] Open
Abstract
Toxoplasma gondii harbors two endosymbiotic organelles: a relict plastid, the apicoplast, and a mitochondrion. The parasite expresses an antioxidant protein, thioredoxin peroxidase 1/2 (TgTPx1/2), that is dually targeted to these organelles. Nuclear-encoded proteins such as TgTPx1/2 are trafficked to the apicoplast via a secretory route through the endoplasmic reticulum (ER) and to the mitochondrion via a non-secretory pathway comprising of translocon uptake. Given the two distinct trafficking pathways for localization to the two organelles, the signals in TgTPx1/2 for this dual targeting are open areas of investigation. Here we show that the signals for apicoplast and mitochondrial trafficking lie in the N-terminal 50 amino acids of the protein and are overlapping. Interestingly, mutational analysis of the overlapping stretch shows that despite this overlap, the signals for individual organellar uptake can be easily separated. Further, deletions in the N-terminus also reveal a 10 amino acid stretch that is responsible for targeting the protein from punctate structures surrounding the apicoplast into the organelle itself. Collectively, results presented in this report suggest that an ambiguous signal sequence for organellar uptake combined with a hierarchy of recognition by the protein trafficking machinery drives the dual targeting of TgTPx1/2.
Collapse
Affiliation(s)
- Pragati Mastud
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, India
| | - Swati Patankar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, India
| |
Collapse
|
28
|
Salunke R, Mourier T, Banerjee M, Pain A, Shanmugam D. Correction: Highly diverged novel subunit composition of apicomplexan F-type ATP synthase identified from Toxoplasma gondii. PLoS Biol 2019; 17:e3000176. [PMID: 30840617 PMCID: PMC6402638 DOI: 10.1371/journal.pbio.3000176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
[This corrects the article DOI: 10.1371/journal.pbio.2006128.].
Collapse
|
29
|
Huet D, Rajendran E, van Dooren GG, Lourido S. Identification of cryptic subunits from an apicomplexan ATP synthase. eLife 2018; 7:e38097. [PMID: 30204085 PMCID: PMC6133553 DOI: 10.7554/elife.38097] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Accepted: 08/17/2018] [Indexed: 01/22/2023] Open
Abstract
The mitochondrial ATP synthase is a macromolecular motor that uses the proton gradient to generate ATP. Proper ATP synthase function requires a stator linking the catalytic and rotary portions of the complex. However, sequence-based searches fail to identify genes encoding stator subunits in apicomplexan parasites like Toxoplasma gondii or the related organisms that cause malaria. Here, we identify 11 previously unknown subunits from the Toxoplasma ATP synthase, which lack homologs outside the phylum. Modeling suggests that two of them, ICAP2 and ICAP18, are distantly related to mammalian stator subunits. Our analysis shows that both proteins form part of the ATP synthase complex. Depletion of ICAP2 leads to aberrant mitochondrial morphology, decreased oxygen consumption, and disassembly of the complex, consistent with its role as an essential component of the Toxoplasma ATP synthase. Our findings highlight divergent features of the central metabolic machinery in apicomplexans, which may reveal new therapeutic opportunities.
Collapse
Affiliation(s)
- Diego Huet
- Whitehead Institute for Biomedical ResearchCambridgeUnited States
| | - Esther Rajendran
- Research School of BiologyAustralian National UniversityCanberraAustralia
| | - Giel G van Dooren
- Research School of BiologyAustralian National UniversityCanberraAustralia
| | - Sebastian Lourido
- Whitehead Institute for Biomedical ResearchCambridgeUnited States
- Department of BiologyMassachusetts Institute of TechnologyCambridgeMassachusetts, United States
| |
Collapse
|
30
|
Seidi A, Muellner-Wong LS, Rajendran E, Tjhin ET, Dagley LF, Aw VYT, Faou P, Webb AI, Tonkin CJ, van Dooren GG. Elucidating the mitochondrial proteome of Toxoplasma gondii reveals the presence of a divergent cytochrome c oxidase. eLife 2018; 7:e38131. [PMID: 30204084 PMCID: PMC6156079 DOI: 10.7554/elife.38131] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2018] [Accepted: 09/09/2018] [Indexed: 12/17/2022] Open
Abstract
The mitochondrion of apicomplexan parasites is critical for parasite survival, although the full complement of proteins that localize to this organelle has not been defined. Here we undertake two independent approaches to elucidate the mitochondrial proteome of the apicomplexan Toxoplasma gondii. We identify approximately 400 mitochondrial proteins, many of which lack homologs in the animals that these parasites infect, and most of which are important for parasite growth. We demonstrate that one such protein, termed TgApiCox25, is an important component of the parasite cytochrome c oxidase (COX) complex. We identify numerous other apicomplexan-specific components of COX, and conclude that apicomplexan COX, and apicomplexan mitochondria more generally, differ substantially in their protein composition from the hosts they infect. Our study highlights the diversity that exists in mitochondrial proteomes across the eukaryotic domain of life, and provides a foundation for defining unique aspects of mitochondrial biology in an important phylum of parasites.
Collapse
Affiliation(s)
- Azadeh Seidi
- Research School of BiologyAustralian National UniversityCanberraAustralia
| | | | - Esther Rajendran
- Research School of BiologyAustralian National UniversityCanberraAustralia
| | - Edwin T Tjhin
- Research School of BiologyAustralian National UniversityCanberraAustralia
| | - Laura F Dagley
- The Walter and Eliza Hall Institute of Medical ResearchVictoriaAustralia
- Department of Medical BiologyUniversity of MelbourneVictoriaAustralia
| | - Vincent YT Aw
- Research School of BiologyAustralian National UniversityCanberraAustralia
| | - Pierre Faou
- Department of Biochemistry and GeneticsLa Trobe Institute for Molecular Science, La Trobe UniversityVictoriaAustralia
| | - Andrew I Webb
- The Walter and Eliza Hall Institute of Medical ResearchVictoriaAustralia
- Department of Medical BiologyUniversity of MelbourneVictoriaAustralia
| | - Christopher J Tonkin
- The Walter and Eliza Hall Institute of Medical ResearchVictoriaAustralia
- Department of Medical BiologyUniversity of MelbourneVictoriaAustralia
| | - Giel G van Dooren
- Research School of BiologyAustralian National UniversityCanberraAustralia
| |
Collapse
|
31
|
Mallo N, Fellows J, Johnson C, Sheiner L. Protein Import into the Endosymbiotic Organelles of Apicomplexan Parasites. Genes (Basel) 2018; 9:E412. [PMID: 30110980 PMCID: PMC6115763 DOI: 10.3390/genes9080412] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2018] [Revised: 07/31/2018] [Accepted: 08/07/2018] [Indexed: 01/26/2023] Open
Abstract
: The organelles of endosymbiotic origin, plastids, and mitochondria, evolved through the serial acquisition of endosymbionts by a host cell. These events were accompanied by gene transfer from the symbionts to the host, resulting in most of the organellar proteins being encoded in the cell nuclear genome and trafficked into the organelle via a series of translocation complexes. Much of what is known about organelle protein translocation mechanisms is based on studies performed in common model organisms; e.g., yeast and humans or Arabidopsis. However, studies performed in divergent organisms are gradually accumulating. These studies provide insights into universally conserved traits, while discovering traits that are specific to organisms or clades. Apicomplexan parasites feature two organelles of endosymbiotic origin: a secondary plastid named the apicoplast and a mitochondrion. In the context of the diseases caused by apicomplexan parasites, the essential roles and divergent features of both organelles make them prime targets for drug discovery. This potential and the amenability of the apicomplexan Toxoplasma gondii to genetic manipulation motivated research about the mechanisms controlling both organelles' biogenesis. Here we provide an overview of what is known about apicomplexan organelle protein import. We focus on work done mainly in T. gondii and provide a comparison to model organisms.
Collapse
Affiliation(s)
- Natalia Mallo
- Wellcome Centre for Molecular Parasitology, University of Glasgow, 120 University Place Glasgow, Glasgow G12 8QQ, UK.
| | - Justin Fellows
- Genetics and Biochemistry Branch, National Institute for Diabetes and Digestive and Kidney Disease, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Carla Johnson
- Wellcome Centre for Molecular Parasitology, University of Glasgow, 120 University Place Glasgow, Glasgow G12 8QQ, UK.
| | - Lilach Sheiner
- Wellcome Centre for Molecular Parasitology, University of Glasgow, 120 University Place Glasgow, Glasgow G12 8QQ, UK.
| |
Collapse
|