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Chen Z, Xie H, Liu J, Zhao J, Huang R, Xiang Y, Wu H, Tian D, Bian E, Xiong Z. Roles of TRPM channels in glioma. Cancer Biol Ther 2024; 25:2338955. [PMID: 38680092 PMCID: PMC11062369 DOI: 10.1080/15384047.2024.2338955] [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: 12/03/2023] [Accepted: 04/01/2024] [Indexed: 05/01/2024] Open
Abstract
Gliomas are the most common type of primary brain tumor. Despite advances in treatment, it remains one of the most aggressive and deadly tumor of the central nervous system (CNS). Gliomas are characterized by high malignancy, heterogeneity, invasiveness, and high resistance to radiotherapy and chemotherapy. It is urgent to find potential new molecular targets for glioma. The TRPM channels consist of TRPM1-TPRM8 and play a role in many cellular functions, including proliferation, migration, invasion, angiogenesis, etc. More and more studies have shown that TRPM channels can be used as new therapeutic targets for glioma. In this review, we first introduce the structure, activation patterns, and physiological functions of TRPM channels. Additionally, the pathological mechanism of glioma mediated by TRPM2, 3, 7, and 8 and the related signaling pathways are described. Finally, we discuss the therapeutic potential of targeting TRPM for glioma.
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Affiliation(s)
- Zhigang Chen
- Department of Neurosurgery, The Translational Research Institute for Neurological Disorders, The First Affiliated Hospital (Yijishan Hospital), Wannan Medical College, Wuhu, P. R. China
- Department of Neurosurgery, The Second Affiliated Hospital of Anhui Medical University, Anhui Medical University, Hefei, China
| | - Han Xie
- Department of Neurosurgery, The Second Affiliated Hospital of Anhui Medical University, Anhui Medical University, Hefei, China
| | - Jun Liu
- Department of Orthopaedics, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
| | - JiaJia Zhao
- Department of Neurosurgery, The Second Affiliated Hospital of Anhui Medical University, Anhui Medical University, Hefei, China
| | - Ruixiang Huang
- Department of Neurosurgery, The Second Affiliated Hospital of Anhui Medical University, Anhui Medical University, Hefei, China
| | - Yufei Xiang
- Department of Neurosurgery, The Second Affiliated Hospital of Anhui Medical University, Anhui Medical University, Hefei, China
| | - Haoyuan Wu
- Department of Neurosurgery, The Second Affiliated Hospital of Anhui Medical University, Anhui Medical University, Hefei, China
| | - Dasheng Tian
- Department of Orthopaedics, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Erbao Bian
- Department of Orthopaedics, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Zhang Xiong
- Department of Neurosurgery, The Translational Research Institute for Neurological Disorders, The First Affiliated Hospital (Yijishan Hospital), Wannan Medical College, Wuhu, P. R. China
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Márquez-Nogueras KM, Kuo IY. Cardiovascular perspectives of the TRP channel polycystin 2. J Physiol 2024; 602:1565-1577. [PMID: 37312633 PMCID: PMC10716366 DOI: 10.1113/jp283835] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Accepted: 06/09/2023] [Indexed: 06/15/2023] Open
Abstract
Calcium release from the endoplasmic reticulum (ER) is predominantly driven by two key ion channel receptors, inositol 1, 4, 5-triphosphate receptor (InsP3R) in non-excitable cells and ryanodine receptor (RyR) in excitable and muscle-based cells. These calcium transients can be modified by other less-studied ion channels, including polycystin 2 (PC2), a member of the transient receptor potential (TRP) family. PC2 is found in various cell types and is evolutionarily conserved with paralogues ranging from single-cell organisms to yeasts and mammals. Interest in the mammalian form of PC2 stems from its disease relevance, as mutations in the PKD2 gene, which encodes PC2, result in autosomal dominant polycystic kidney disease (ADPKD). This disease is characterized by renal and liver cysts, and cardiovascular extrarenal manifestations. However, in contrast to the well-defined roles of many TRP channels, the role of PC2 remains unknown, as it has different subcellular locations, and the functional understanding of the channel in each location is still unclear. Recent structural and functional studies have shed light on this channel. Moreover, studies on cardiovascular tissues have demonstrated a diverse role of PC2 in these tissues compared to that in the kidney. We highlight recent advances in understanding the role of this channel in the cardiovascular system and discuss the functional relevance of PC2 in non-renal cells.
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Affiliation(s)
- Karla M Márquez-Nogueras
- Department of Cell and Molecular Physiology, Stritch School of Medicine, Loyola University Chicago, Maywood, IL, USA
| | - Ivana Y Kuo
- Department of Cell and Molecular Physiology, Stritch School of Medicine, Loyola University Chicago, Maywood, IL, USA
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3
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Hortua Triana MA, Márquez-Nogueras KM, Fazli MS, Quinn S, Moreno SNJ. Regulation of calcium entry by cyclic GMP signaling in Toxoplasma gondii. J Biol Chem 2024; 300:105771. [PMID: 38382669 PMCID: PMC10959671 DOI: 10.1016/j.jbc.2024.105771] [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: 08/01/2023] [Revised: 01/09/2024] [Accepted: 01/28/2024] [Indexed: 02/23/2024] Open
Abstract
Ca2+ signaling impacts almost every aspect of cellular life. Ca2+ signals are generated through the opening of ion channels that permit the flow of Ca2+ down an electrochemical gradient. Cytosolic Ca2+ fluctuations can be generated through Ca2+ entry from the extracellular milieu or release from intracellular stores. In Toxoplasma gondii, Ca2+ ions play critical roles in several essential functions for the parasite, like invasion of host cells, motility, and egress. Plasma membrane Ca2+ entry in T. gondii was previously shown to be activated by cytosolic calcium and inhibited by the voltage-operated Ca2+ channel blocker nifedipine. However, Ca2+ entry in T. gondii did not show the classical characteristics of store regulation. In this work, we characterized the mechanism by which cytosolic Ca2+ regulates plasma membrane Ca2+ entry in extracellular T. gondii tachyzoites loaded with the Ca2+ indicator Fura-2. We compared the inhibition by nifedipine with the effect of the broad spectrum TRP channel inhibitor, anthranilic acid or ACA, and we find that both inhibitors act on different Ca2+ entry activities. We demonstrate, using pharmacological and genetic tools, that an intracellular signaling pathway engaging cyclic GMP, protein kinase G, Ca2+, and the phosphatidyl inositol phospholipase C affects Ca2+ entry and we present a model for crosstalk between cyclic GMP and cytosolic Ca2+ for the activation of T. gondii's lytic cycle traits.
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Affiliation(s)
- Miryam A Hortua Triana
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
| | | | | | - Shannon Quinn
- Department of Computer Science, University of Georgia, Athens, Georgia, USA
| | - Silvia N J Moreno
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA; Department of Cellular Biology, University of Georgia, Athens, Georgia, USA.
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4
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Chan AW, Broncel M, Yifrach E, Haseley NR, Chakladar S, Andree E, Herneisen AL, Shortt E, Treeck M, Lourido S. Analysis of CDPK1 targets identifies a trafficking adaptor complex that regulates microneme exocytosis in Toxoplasma. eLife 2023; 12:RP85654. [PMID: 37933960 PMCID: PMC10629828 DOI: 10.7554/elife.85654] [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: 11/08/2023] Open
Abstract
Apicomplexan parasites use Ca2+-regulated exocytosis to secrete essential virulence factors from specialized organelles called micronemes. Ca2+-dependent protein kinases (CDPKs) are required for microneme exocytosis; however, the molecular events that regulate trafficking and fusion of micronemes with the plasma membrane remain unresolved. Here, we combine sub-minute resolution phosphoproteomics and bio-orthogonal labeling of kinase substrates in Toxoplasma gondii to identify 163 proteins phosphorylated in a CDPK1-dependent manner. In addition to known regulators of secretion, we identify uncharacterized targets with predicted functions across signaling, gene expression, trafficking, metabolism, and ion homeostasis. One of the CDPK1 targets is a putative HOOK activating adaptor. In other eukaryotes, HOOK homologs form the FHF complex with FTS and FHIP to activate dynein-mediated trafficking of endosomes along microtubules. We show the FHF complex is partially conserved in T. gondii, consisting of HOOK, an FTS homolog, and two parasite-specific proteins (TGGT1_306920 and TGGT1_316650). CDPK1 kinase activity and HOOK are required for the rapid apical trafficking of micronemes as parasites initiate motility. Moreover, parasites lacking HOOK or FTS display impaired microneme protein secretion, leading to a block in the invasion of host cells. Taken together, our work provides a comprehensive catalog of CDPK1 targets and reveals how vesicular trafficking has been tuned to support a parasitic lifestyle.
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Affiliation(s)
- Alex W Chan
- Whitehead Institute for Biomedical ResearchCambridgeUnited States
- Biology Department, Massachusetts Institute of TechnologyCambridgeUnited States
| | - Malgorzata Broncel
- Signaling in Apicomplexan Parasites Laboratory, The Francis Crick InstituteLondonUnited Kingdom
| | - Eden Yifrach
- Whitehead Institute for Biomedical ResearchCambridgeUnited States
| | - Nicole R Haseley
- Whitehead Institute for Biomedical ResearchCambridgeUnited States
| | | | - Elena Andree
- Whitehead Institute for Biomedical ResearchCambridgeUnited States
| | - Alice L Herneisen
- Whitehead Institute for Biomedical ResearchCambridgeUnited States
- Biology Department, Massachusetts Institute of TechnologyCambridgeUnited States
| | - Emily Shortt
- Whitehead Institute for Biomedical ResearchCambridgeUnited States
| | - Moritz Treeck
- Signaling in Apicomplexan Parasites Laboratory, The Francis Crick InstituteLondonUnited Kingdom
| | - Sebastian Lourido
- Whitehead Institute for Biomedical ResearchCambridgeUnited States
- Biology Department, Massachusetts Institute of TechnologyCambridgeUnited States
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5
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Chan AW, Broncel M, Yifrach E, Haseley N, Chakladar S, Andree E, Herneisen AL, Shortt E, Treeck M, Lourido S. Analysis of CDPK1 targets identifies a trafficking adaptor complex that regulates microneme exocytosis in Toxoplasma. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.11.523553. [PMID: 36712004 PMCID: PMC9882037 DOI: 10.1101/2023.01.11.523553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Apicomplexan parasites use Ca2+-regulated exocytosis to secrete essential virulence factors from specialized organelles called micronemes. Ca2+-dependent protein kinases (CDPKs) are required for microneme exocytosis; however, the molecular events that regulate trafficking and fusion of micronemes with the plasma membrane remain unresolved. Here, we combine sub-minute resolution phosphoproteomics and bio-orthogonal labeling of kinase substrates in Toxoplasma gondii to identify 163 proteins phosphorylated in a CDPK1-dependent manner. In addition to known regulators of secretion, we identify uncharacterized targets with predicted functions across signaling, gene expression, trafficking, metabolism, and ion homeostasis. One of the CDPK1 targets is a putative HOOK activating adaptor. In other eukaryotes, HOOK homologs form the FHF complex with FTS and FHIP to activate dynein-mediated trafficking of endosomes along microtubules. We show the FHF complex is partially conserved in T. gondii, consisting of HOOK, an FTS homolog, and two parasite-specific proteins (TGGT1_306920 and TGGT1_316650). CDPK1 kinase activity and HOOK are required for the rapid apical trafficking of micronemes as parasites initiate motility. Moreover, parasites lacking HOOK or FTS display impaired microneme protein secretion, leading to a block in the invasion of host cells. Taken together, our work provides a comprehensive catalog of CDPK1 targets and reveals how vesicular trafficking has been tuned to support a parasitic lifestyle.
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Affiliation(s)
- Alex W Chan
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA
- Biology Department, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Malgorzata Broncel
- Signaling in Apicomplexan Parasites Laboratory, The Francis Crick Institute, London, UK
| | - Eden Yifrach
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA
| | - Nicole Haseley
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA
| | | | - Elena Andree
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA
| | - Alice L Herneisen
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA
- Biology Department, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Emily Shortt
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA
| | - Moritz Treeck
- Signaling in Apicomplexan Parasites Laboratory, The Francis Crick Institute, London, UK
| | - Sebastian Lourido
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA
- Biology Department, Massachusetts Institute of Technology, Cambridge, MA, USA
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Quan JJ, Nikolov LA, Sha J, Wohlschlegel JA, Bradley PJ. Toxoplasma gondii encodes an array of TBC-domain containing proteins including an essential regulator that targets Rab2 in the secretory pathway. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.28.542599. [PMID: 37398139 PMCID: PMC10312441 DOI: 10.1101/2023.05.28.542599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
Toxoplasma gondii resides in its intracellular niche by employing a series of specialized secretory organelles that play roles in invasion, host-cell manipulation and parasite replication. Rab GTPases are major regulators of the parasite's secretory traffic that function as nucleotide dependent molecular switches to control vesicle trafficking. While many of the Rab proteins have been characterized in T. gondii , precisely how these Rabs are regulated remains poorly understood. To better understand the parasite's secretory traffic, we investigated the entire family of Tre2-Bub2-Cdc16 (TBC)-domain containing proteins, which are known to be involved in vesicle fusion and secretory protein trafficking. We first determined the localization of all 18 TBC-domain containing proteins to discrete regions of the secretory pathway or other vesicles in the parasite. We then use an auxin-inducible degron approach to demonstrate that the protozoan-specific TgTBC9 protein that localizes to the ER is essential for parasite survival. Knockdown of TgTBC9 results in parasite growth arrest and affects the organization of the ER and Golgi apparatus. We show that the conserved dual-finger active site in the TBC-domain of the protein is critical for its GTPase-activating protein (GAP) function and that the P. falciparum orthologue of TgTBC9 can rescue the lethal knockdown. We additionally show by immunoprecipitation and yeast two hybrid analyses that TgTBC9 directly binds Rab2, indicating that this TBC-Rab pair controls ER to Golgi traffic in the parasite. Together, these studies identify the first essential TBC protein described in any protozoan, provide new insight into intracellular vesicle trafficking in T. gondii , and reveal promising targets for the design of novel therapeutics that can specifically target apicomplexan parasites.
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Huţanu DE, Oprita G, Domocos D, Selescu T, Manolache A, Stratulat T, Sauer SK, Tunaru S, Babes A, Babes RM. The antimalarial artemisinin is a non-electrophilic agonist of the transient receptor potential ankyrin type 1 receptor-channel. Eur J Pharmacol 2023; 939:175467. [PMID: 36543288 DOI: 10.1016/j.ejphar.2022.175467] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 12/12/2022] [Accepted: 12/13/2022] [Indexed: 12/23/2022]
Abstract
Artemisinin and its derivatives are the main therapeutic drugs against Plasmodium protists, the causative agents of malaria. While several putative mechanisms of action have been proposed, the precise molecular targets of these compounds have not been fully elucidated. In addition to their antimalarial properties, artemisinins have been reported to act as anti-tumour agents and certain antinociceptive effects have also been proposed. We investigated the effect of the parent compound, artemisinin, on a number of temperature-gated Transient Receptor Potential ion channels (so called thermoTRPs), given their demonstrated roles in pain-sensing and cancer. We report that artemisinin acts as an agonist of the Transient Receptor Potential Ankyrin type 1 (TRPA1) receptor channel. Artemisinin was able to evoke calcium transients in HEK293T cells expressing recombinant human TRPA1, as well as in a subpopulation of mouse dorsal root ganglion (DRG) neurons which also responded to the selective TRPA1 agonist allyl isothiocyanate (AITC) and these responses were reversibly abolished by the selective TRPA1 antagonist A967079. Artemisinin also triggered whole-cell currents in HEK293T cells transiently transfected with human TRPA1, as well as in TRPA1-expressing DRG neurons, and these currents were inhibited by A967079. Interestingly, using human TRPA1 mutants, we demonstrate that artemisinin acts as a non-electrophilic agonist of TRPA1, activating the channel in a similar manner to carvacrol and menthol. These results may provide a better understanding of the biological actions of the very important antimalarial and anti-tumour agent artemisinin.
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Affiliation(s)
- Debora-Elena Huţanu
- Department of Anatomy, Physiology and Biophysics, Faculty of Biology, University of Bucharest, Splaiul Independenţei 91-95, 050095, Bucharest, Romania
| | - George Oprita
- Department of Anatomy, Physiology and Biophysics, Faculty of Biology, University of Bucharest, Splaiul Independenţei 91-95, 050095, Bucharest, Romania
| | - Dan Domocos
- Department of Anatomy, Physiology and Biophysics, Faculty of Biology, University of Bucharest, Splaiul Independenţei 91-95, 050095, Bucharest, Romania; Cell Signalling Research Group, Institute of Biochemistry of the Romanian Academy, Splaiul Independenţei 296, 060031, Bucharest, Romania
| | - Tudor Selescu
- Department of Anatomy, Physiology and Biophysics, Faculty of Biology, University of Bucharest, Splaiul Independenţei 91-95, 050095, Bucharest, Romania
| | - Alexandra Manolache
- Department of Anatomy, Physiology and Biophysics, Faculty of Biology, University of Bucharest, Splaiul Independenţei 91-95, 050095, Bucharest, Romania
| | - Teodora Stratulat
- Department of Anatomy, Physiology and Biophysics, Faculty of Biology, University of Bucharest, Splaiul Independenţei 91-95, 050095, Bucharest, Romania; Cell Signalling Research Group, Institute of Biochemistry of the Romanian Academy, Splaiul Independenţei 296, 060031, Bucharest, Romania
| | - Susanne K Sauer
- Institute of Physiology and Experimental Pathophysiology, Friedrich-Alexander University of Erlangen-Nuremberg, Universitaetsstrasse 17, 91054, Erlangen, Germany
| | - Sorin Tunaru
- Cell Signalling Research Group, Institute of Biochemistry of the Romanian Academy, Splaiul Independenţei 296, 060031, Bucharest, Romania
| | - Alexandru Babes
- Department of Anatomy, Physiology and Biophysics, Faculty of Biology, University of Bucharest, Splaiul Independenţei 91-95, 050095, Bucharest, Romania.
| | - Ramona-Madalina Babes
- Department of Biophysics, "Carol Davila" University of Medicine and Pharmacy, Str. Dionisie Lupu 37, 020021, Bucharest, Romania
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8
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Down the membrane hole: Ion channels in protozoan parasites. PLoS Pathog 2022; 18:e1011004. [PMID: 36580479 PMCID: PMC9799330 DOI: 10.1371/journal.ppat.1011004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Parasitic diseases caused by protozoans are highly prevalent around the world, disproportionally affecting developing countries, where coinfection with other microorganisms is common. Control and treatment of parasitic infections are constrained by the lack of specific and effective drugs, plus the rapid emergence of resistance. Ion channels are main drug targets for numerous diseases, but their potential against protozoan parasites is still untapped. Ion channels are membrane proteins expressed in all types of cells, allowing for the flow of ions between compartments, and regulating cellular functions such as membrane potential, excitability, volume, signaling, and death. Channels and transporters reside at the interface between parasites and their hosts, controlling nutrient uptake, viability, replication, and infectivity. To understand how ion channels control protozoan parasites fate and to evaluate their suitability for therapeutics, we must deepen our knowledge of their structure, function, and modulation. However, methodological approaches commonly used in mammalian cells have proven difficult to apply in protozoans. This review focuses on ion channels described in protozoan parasites of clinical relevance, mainly apicomplexans and trypanosomatids, highlighting proteins for which molecular and functional evidence has been correlated with their physiological functions.
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9
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In vitro cultivation methods for coccidian parasite research. Int J Parasitol 2022:S0020-7519(22)00153-9. [DOI: 10.1016/j.ijpara.2022.10.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 09/29/2022] [Accepted: 10/09/2022] [Indexed: 11/17/2022]
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10
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Cui J, Yang X, Yang J, Jia R, Feng Y, Shen B. A Coccidia-Specific Phosphate Transporter Is Essential for the Growth of Toxoplasma gondii Parasites. Microbiol Spectr 2022; 10:e0218622. [PMID: 36094254 PMCID: PMC9604053 DOI: 10.1128/spectrum.02186-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Accepted: 08/26/2022] [Indexed: 12/31/2022] Open
Abstract
Toxoplasma gondii is an obligate intracellular parasite that acquires all necessary nutrients from the hosts, but the exact nutrient acquisition mechanisms are poorly understood. Here, we identified three putative phosphate transporters in T. gondii. TgPiT and TgPT2 are mainly on the plasma membrane, whereas TgmPT is localized to the mitochondrion. TgPiT and TgmPT are widely present and conserved in apicomplexan parasites that include Plasmodium and Eimeria species. Nonetheless, they are dispensable for the growth and virulence of Toxoplasma. TgPT2, on the other hand, is restricted to coccidia parasites and is essential for Toxoplasma survival. TgPT2 depletion led to reduced motility and invasion, as well as growth arrest of the parasites both in vitro and in vivo. Both TgPiT and TgPT2 have phosphate transport activities and contribute to parasites' inorganic phosphate (Pi) absorption. Interestingly, the Pi importing activity of Toxoplasma parasites could be competitively inhibited by ATP and AMP. Furthermore, direct uptake of 32P-ATP was also observed, indicating the parasites' ability to scavenge host ATP. Nonetheless, ATP/AMP import is not mediated by TgPiT or TgPT2, suggesting additional mechanisms. Together, these results show the complex pathways of phosphate transport in Toxoplasma, and TgPT2 is a potential target for antitoxoplasmic intervention design due to its essential role in parasite growth. IMPORTANCE To grow and survive within host cells, Toxoplasma must scavenge necessary nutrients from hosts to support its parasitism. Transporters located in the plasma membrane of the parasites play critical roles in nutrient acquisition. Toxoplasma encodes a large number of transporters, but so far, only a few have been characterized. In this study, we identified two phosphate transporters, TgPiT and TgPT2, to localize to the plasma membrane of Toxoplasma. Although both TgPiT and TgPT2 possess phosphate transport activities, only the novel transporter TgPT2 was essential for parasite growth, both in vitro and in vivo. In addition, TgPT2 and its orthologs are only present in coccidia parasites. As such, TgPT2 represents a potential target for drug design against toxoplasmosis. In addition, our data indicated that Toxoplasma can take up ATP and AMP from the environment, providing new insights into the energy metabolism of Toxoplasma.
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Affiliation(s)
- Jianmin Cui
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei Province, People’s Republic of China
- Key Laboratory of Preventive Medicine in Hubei Province, Huazhong Agricultural University, Wuhan, Hubei Province, People’s Republic of China
| | - Xuke Yang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei Province, People’s Republic of China
- Key Laboratory of Preventive Medicine in Hubei Province, Huazhong Agricultural University, Wuhan, Hubei Province, People’s Republic of China
| | - Jichao Yang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei Province, People’s Republic of China
- Key Laboratory of Preventive Medicine in Hubei Province, Huazhong Agricultural University, Wuhan, Hubei Province, People’s Republic of China
| | - Ruilian Jia
- Center for Emerging and Zoonotic Diseases, College of Veterinary Medicine, South China Agricultural University, Guangzhou, People’s Republic of China
| | - Yaoyu Feng
- Center for Emerging and Zoonotic Diseases, College of Veterinary Medicine, South China Agricultural University, Guangzhou, People’s Republic of China
| | - Bang Shen
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei Province, People’s Republic of China
- Key Laboratory of Preventive Medicine in Hubei Province, Huazhong Agricultural University, Wuhan, Hubei Province, People’s Republic of China
- Hubei Hongshan Laboratory, Wuhan, Hubei Province, People’s Republic of China
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11
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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: 16] [Impact Index Per Article: 8.0] [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.
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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
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12
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Fu Y, Brown KM, Jones NG, Moreno SNJ, Sibley LD. Toxoplasma bradyzoites exhibit physiological plasticity of calcium and energy stores controlling motility and egress. eLife 2021; 10:e73011. [PMID: 34860156 PMCID: PMC8683080 DOI: 10.7554/elife.73011] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 12/03/2021] [Indexed: 01/01/2023] Open
Abstract
Toxoplasma gondii has evolved different developmental stages for disseminating during acute infection (i.e., tachyzoites) and establishing chronic infection (i.e., bradyzoites). Calcium ion (Ca2+) signaling tightly regulates the lytic cycle of tachyzoites by controlling microneme secretion and motility to drive egress and cell invasion. However, the roles of Ca2+ signaling pathways in bradyzoites remain largely unexplored. Here, we show that Ca2+ responses are highly restricted in bradyzoites and that they fail to egress in response to agonists. Development of dual-reporter parasites revealed dampened Ca2+ responses and minimal microneme secretion by bradyzoites induced in vitro or harvested from infected mice and tested ex vivo. Ratiometric Ca2+ imaging demonstrated lower Ca2+ basal levels, reduced magnitude, and slower Ca2+ kinetics in bradyzoites compared with tachyzoites stimulated with agonists. Diminished responses in bradyzoites were associated with downregulation of Ca2+-ATPases involved in intracellular Ca2+ storage in the endoplasmic reticulum (ER) and acidocalcisomes. Once liberated from cysts by trypsin digestion, bradyzoites incubated in glucose plus Ca2+ rapidly restored their intracellular Ca2+ and ATP stores, leading to enhanced gliding. Collectively, our findings indicate that intracellular bradyzoites exhibit dampened Ca2+ signaling and lower energy levels that restrict egress, and yet upon release they rapidly respond to changes in the environment to regain motility.
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Affiliation(s)
- Yong Fu
- Department of Molecular Microbiology, Washington University in St. Louis, School of MedicineSt LouisUnited States
| | - Kevin M Brown
- Department of Molecular Microbiology, Washington University in St. Louis, School of MedicineSt LouisUnited States
| | - Nathaniel G Jones
- Department of Molecular Microbiology, Washington University in St. Louis, School of MedicineSt LouisUnited States
| | - Silvia NJ Moreno
- Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of GeorgiaAthensUnited States
| | - L David Sibley
- Department of Molecular Microbiology, Washington University in St. Louis, School of MedicineSt LouisUnited States
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Calcium signaling in intracellular protist parasites. Curr Opin Microbiol 2021; 64:33-40. [PMID: 34571430 DOI: 10.1016/j.mib.2021.09.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 07/28/2021] [Accepted: 09/07/2021] [Indexed: 11/21/2022]
Abstract
Calcium ion (Ca2+) signaling is one of the most frequently employed mechanisms of signal transduction by eukaryotic cells, and starts with either Ca2+ release from intracellular stores or Ca2+ entry through the plasma membrane. In intracellular protist parasites Ca2+ signaling initiates a sequence of events that may facilitate their invasion of host cells, respond to environmental changes within the host, or regulate the function of their intracellular organelles. In this review we examine recent findings in Ca2+ signaling in two groups of intracellular protist parasites that have been studied in more detail, the apicomplexan and the trypanosomatid parasites.
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14
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Theopold U, Barragan A. TRP channels, the missing link for Ca 2+ tuning by a unicellular eukaryotic parasite? Cell Calcium 2021; 98:102449. [PMID: 34332260 DOI: 10.1016/j.ceca.2021.102449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 07/21/2021] [Indexed: 10/20/2022]
Abstract
Sensing and responding to changes in the cellular environments are essential for the diverse family of Apicomplexan parasites, which undergo complex life cycles comprised of both extracellular and obligate intracellular stages. Despite evidence of paramount roles for Ca2+, the molecular players behind how parasites sense Ca2+ and initiate Ca2+ signaling cascades have remained enigmatic. In a recent publication, Marquez-Nogueras et al., identify a transient receptor potential (TRP)-like channel in Toxoplasma gondii and show its implication in the crucial processes of parasite invasion and egress from host cells.
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Affiliation(s)
- Ulrich Theopold
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Antonio Barragan
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden.
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