1
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Heissler SM, Chinthalapudi K. Structural and functional mechanisms of actin isoforms. FEBS J 2024. [PMID: 38779987 DOI: 10.1111/febs.17153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2024] [Revised: 04/01/2024] [Accepted: 04/23/2024] [Indexed: 05/25/2024]
Abstract
Actin is a highly conserved and fundamental protein in eukaryotes and participates in a broad spectrum of cellular functions. Cells maintain a conserved ratio of actin isoforms, with muscle and non-muscle actins representing the main actin isoforms in muscle and non-muscle cells, respectively. Actin isoforms have specific and redundant functional roles and display different biochemistries, cellular localization, and interactions with myosins and actin-binding proteins. Understanding the specific roles of actin isoforms from the structural and functional perspective is crucial for elucidating the intricacies of cytoskeletal dynamics and regulation and their implications in health and disease. Here, we review how the structure contributes to the functional mechanisms of actin isoforms with a special emphasis on the questions of how post-translational modifications and disease-linked mutations affect actin isoforms biochemistry, function, and interaction with actin-binding proteins and myosin motors.
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Affiliation(s)
- Sarah M Heissler
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart & Lung Research Institute, The Ohio State University, Columbus, OH, USA
| | - Krishna Chinthalapudi
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart & Lung Research Institute, The Ohio State University, Columbus, OH, USA
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2
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Verhoef JMJ, Boshoven C, Evers F, Akkerman LJ, Gijsbrechts BCA, van de Vegte-Bolmer M, van Gemert GJ, Vaidya AB, Kooij TWA. Detailing organelle division and segregation in Plasmodium falciparum. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.30.577899. [PMID: 38352445 PMCID: PMC10862848 DOI: 10.1101/2024.01.30.577899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/23/2024]
Abstract
The malaria causing parasite, Plasmodium falciparum, replicates through a tightly orchestrated process termed schizogony, where approximately 32 daughter parasites are formed in a single infected red blood cell and thousands of daughter cells in mosquito or liver stages. One-per-cell organelles, such as the mitochondrion and apicoplast, need to be properly divided and segregated to ensure a complete set of organelles per daughter parasites. Although this is highly essential, details about the processes and mechanisms involved remain unknown. We developed a new reporter parasite line that allows visualization of the mitochondrion in blood and mosquito stages. Using high-resolution 3D-imaging, we found that the mitochondrion orients in a cartwheel structure, prior to stepwise, non-geometric division during the last stage of schizogony. Analysis of focused ion beam scanning electron microscopy (FIB-SEM) data confirmed these mitochondrial division stages. Furthermore, these data allowed us to elucidate apicoplast division steps, highlighted its close association with the mitochondrion, and showed putative roles of the centriolar plaques (CPs) in apicoplast segregation. These observations form the foundation for a new detailed mechanistic model of mitochondrial and apicoplast division and segregation during P. falciparum schizogony and pave the way for future studies into the proteins and protein complexes involved in organelle division and segregation.
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Affiliation(s)
- Julie M J Verhoef
- Department of Medical Microbiology, Radboudumc Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Cas Boshoven
- Department of Medical Microbiology, Radboudumc Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Felix Evers
- Department of Medical Microbiology, Radboudumc Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Laura J Akkerman
- Department of Medical Microbiology, Radboudumc Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Barend C A Gijsbrechts
- Department of Medical Microbiology, Radboudumc Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Marga van de Vegte-Bolmer
- Department of Medical Microbiology, Radboudumc Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Geert-Jan van Gemert
- Department of Medical Microbiology, Radboudumc Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Akhil B Vaidya
- Center for Molecular Parasitology, Institute for Molecular Medicine and Infectious Disease, Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, USA
| | - Taco W A Kooij
- Department of Medical Microbiology, Radboudumc Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, The Netherlands
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3
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Kellermeier JA, Heaslip AT. Myosin F controls actin organization and dynamics in Toxoplasma gondii. Mol Biol Cell 2024; 35:ar57. [PMID: 38416592 PMCID: PMC11064658 DOI: 10.1091/mbc.e23-12-0510] [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: 01/02/2024] [Revised: 02/14/2024] [Accepted: 02/21/2024] [Indexed: 03/01/2024] Open
Abstract
Intracellular cargo transport is a ubiquitous cellular process in all eukaryotes. In many cell types, membrane bound cargo is associated with molecular motors which transport cargo along microtubule and actin tracks. In Toxoplasma gondii (T. gondii), an obligate intracellular parasite in the phylum Apicomplexa, organization of the endomembrane pathway depends on actin and an unconventional myosin motor, myosin F (MyoF). Loss of MyoF and actin disrupts vesicle transport, organelle positioning, and division of the apicoplast, a nonphotosynthetic plastid organelle. How this actomyosin system contributes to these cellular functions is still unclear. Using live-cell imaging, we observed that MyoF-EmeraldFP (MyoF-EmFP) displayed a dynamic and filamentous-like organization in the parasite cytosol, reminiscent of cytosolic actin filament dynamics. MyoF was not associated with the Golgi, apicoplast or dense granule surfaces, suggesting that it does not function using the canonical cargo transport mechanism. Instead, we found that loss of MyoF resulted in a dramatic rearrangement of the actin cytoskeleton in interphase parasites accompanied by significantly reduced actin dynamics. However, actin organization during parasite replication and motility was unaffected by the loss of MyoF. These findings revealed that MyoF is an actin organizing protein in Toxoplasma and facilitates cargo movement using an unconventional transport mechanism.
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Affiliation(s)
- Jacob A. Kellermeier
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT 06269
| | - Aoife T. Heaslip
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT 06269
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4
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Ornitz Oliveira Souza R, Yang C, Arrizabalaga G. Myosin A and F-Actin play a critical role in mitochondrial dynamics and inheritance in Toxoplasma gondii. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.18.585462. [PMID: 38562694 PMCID: PMC10983951 DOI: 10.1101/2024.03.18.585462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
The single mitochondrion of the obligate intracellular parasite Toxoplasma gondii is highly dynamic. Toxoplasma's mitochondrion changes morphology as the parasite moves from the intracellular to the extracellular environment and during division. Toxoplasma's mitochondrial dynamic is dependent on an outer mitochondrion membrane-associated protein LMF1 and its interaction with IMC10, a protein localized at the inner membrane complex (IMC). In the absence of either LMF1 or IMC10, parasites have defective mitochondrial morphology and inheritance defects. As little is known about mitochondrial inheritance in Toxoplasma, we have used the LMF1/IMC10 tethering complex as an entry point to dissect the machinery behind this process. Using a yeast two-hybrid screen, we previously identified Myosin A (MyoA) as a putative interactor of LMF1. Although MyoA is known to be located at the parasite's pellicle, we now show through ultrastructure expansion microscopy (U-ExM) that this protein accumulates around the mitochondrion in the late stages of parasite division. Parasites lacking MyoA show defective mitochondrial morphology and a delay in mitochondrion delivery to the daughter parasite buds during division, indicating that this protein is involved in organellar inheritance. Disruption of the parasite's actin network also affects mitochondrion morphology. We also show that parasite-extracted mitochondrion vesicles interact with actin filaments. Interestingly, mitochondrion vesicles extracted out of parasites lacking LMF1 pulled down less actin, showing that LMF1 might be important for mitochondrion and actin interaction. Accordingly, we are showing for the first time that actin and Myosin A are important for Toxoplasma mitochondrial morphology and inheritance.
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Affiliation(s)
| | - Chunlin Yang
- Department of Pharmacology and Toxicology, Indiana University School of Medicine
| | - Gustavo Arrizabalaga
- Department of Pharmacology and Toxicology, Indiana University School of Medicine
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5
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Hvorecny KL, Sladewski TE, De La Cruz EM, Kollman JM, Heaslip AT. Toxoplasma gondii actin filaments are tuned for rapid disassembly and turnover. Nat Commun 2024; 15:1840. [PMID: 38418447 PMCID: PMC10902351 DOI: 10.1038/s41467-024-46111-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Accepted: 02/14/2024] [Indexed: 03/01/2024] Open
Abstract
The cytoskeletal protein actin plays a critical role in the pathogenicity of the intracellular parasite, Toxoplasma gondii, mediating invasion and egress, cargo transport, and organelle inheritance. Advances in live cell imaging have revealed extensive filamentous actin networks in the Apicomplexan parasite, but there are conflicting data regarding the biochemical and biophysical properties of Toxoplasma actin. Here, we imaged the in vitro assembly of individual Toxoplasma actin filaments in real time, showing that native, unstabilized filaments grow tens of microns in length. Unlike skeletal muscle actin, Toxoplasma filaments intrinsically undergo rapid treadmilling due to a high critical concentration, fast monomer dissociation, and rapid nucleotide exchange. Cryo-EM structures of jasplakinolide-stabilized and native (i.e. unstabilized) filaments show an architecture like skeletal actin, with differences in assembly contacts in the D-loop that explain the dynamic nature of the filament, likely a conserved feature of Apicomplexan actin. This work demonstrates that evolutionary changes at assembly interfaces can tune the dynamic properties of actin filaments without disrupting their conserved structure.
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Affiliation(s)
- Kelli L Hvorecny
- Department of Biochemistry, University of Washington, Seattle, WA, USA
| | - Thomas E Sladewski
- Department of Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT, USA
| | - Enrique M De La Cruz
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Justin M Kollman
- Department of Biochemistry, University of Washington, Seattle, WA, USA.
| | - Aoife T Heaslip
- Department of Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT, USA.
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6
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Reber S, Singer M, Frischknecht F. Cytoskeletal dynamics in parasites. Curr Opin Cell Biol 2024; 86:102277. [PMID: 38048658 DOI: 10.1016/j.ceb.2023.102277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 10/12/2023] [Accepted: 10/17/2023] [Indexed: 12/06/2023]
Abstract
Cytoskeletal dynamics are essential for cellular homeostasis and development for both metazoans and protozoans. The function of cytoskeletal elements in protozoans can diverge from that of metazoan cells, with microtubules being more stable and actin filaments being more dynamic. This is particularly striking in protozoan parasites that evolved to enter metazoan cells. Here, we review recent progress towards understanding cytoskeletal dynamics in protozoan parasites, with a focus on divergent properties compared to classic model organisms.
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Affiliation(s)
- Simone Reber
- Max Planck Institute for Infection Biology, 10117 Berlin, Germany; University of Applied Sciences Berlin, 13353 Berlin, Germany
| | - Mirko Singer
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical Faculty, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany; German Center for Infection Research, DZIF Partner Site Heidelberg, Heidelberg, Germany.
| | - Friedrich Frischknecht
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical Faculty, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany; German Center for Infection Research, DZIF Partner Site Heidelberg, Heidelberg, Germany
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7
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Tomasina R, González FC, Echeverría S, Cabrera A, Robello C. Insights into the Cell Division of Neospora caninum. Microorganisms 2023; 12:61. [PMID: 38257886 PMCID: PMC10818811 DOI: 10.3390/microorganisms12010061] [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: 11/02/2023] [Revised: 12/14/2023] [Accepted: 12/20/2023] [Indexed: 01/24/2024] Open
Abstract
Neospora caninum is an apicomplexan protozoan parasite responsible for causing neosporosis in a range of animal species. It results in substantial economic losses in the livestock industry and poses significant health risks to companion and wild animals. Central to its survival and pathogenicity is the process of cell division, which remains poorly understood in this parasite. In this study, we explored the cell division of Neospora caninum using a combination of modern and classic imaging tools, emphasizing its pivotal role in perpetuating the parasite's life cycle and contributing to its ability to persist within host organisms. We described the intricacies of endodyogeny in Neospora caninum, detailing the dynamics of the cell assembly and the nuclear division by ultrastructure expansion microscopy and regular confocal microscopy. Furthermore, we explored the centrosome dynamics, the centrioles and the apicoplast through the advancement of the cell cycle. Our analysis described with unprecedented detail, the endodyogeny in this parasite. By advancing our understanding of these molecular mechanisms, we aimed to inspire innovative strategies for disease management and control, with the ultimate goal of mitigating the devastating impact of neosporosis on animal health and welfare.
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Affiliation(s)
- Ramiro Tomasina
- Laboratorio de Interacciones Hospedero Patógeno, Institut Pasteur de Montevideo, Montevideo 11400, Uruguay; (R.T.); (F.C.G.); (S.E.); (A.C.)
- Departamento de Parasitología y Micología, Facultad de Medicina, Universidad de la República, Montevideo 11800, Uruguay
| | - Fabiana C. González
- Laboratorio de Interacciones Hospedero Patógeno, Institut Pasteur de Montevideo, Montevideo 11400, Uruguay; (R.T.); (F.C.G.); (S.E.); (A.C.)
| | - Soledad Echeverría
- Laboratorio de Interacciones Hospedero Patógeno, Institut Pasteur de Montevideo, Montevideo 11400, Uruguay; (R.T.); (F.C.G.); (S.E.); (A.C.)
| | - Andrés Cabrera
- Laboratorio de Interacciones Hospedero Patógeno, Institut Pasteur de Montevideo, Montevideo 11400, Uruguay; (R.T.); (F.C.G.); (S.E.); (A.C.)
- Departamento de Parasitología y Micología, Facultad de Medicina, Universidad de la República, Montevideo 11800, Uruguay
| | - Carlos Robello
- Laboratorio de Interacciones Hospedero Patógeno, Institut Pasteur de Montevideo, Montevideo 11400, Uruguay; (R.T.); (F.C.G.); (S.E.); (A.C.)
- Departamento de Bioquímica, Facultad de Medicina, Universidad de la República, Montevideo 11800, Uruguay
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8
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Wagner M, Song Y, Jiménez-Ruiz E, Härtle S, Meissner M. The SUN-like protein TgSLP1 is essential for nuclear division in the apicomplexan parasite Toxoplasma gondii. J Cell Sci 2023; 136:jcs260337. [PMID: 37815466 PMCID: PMC10629696 DOI: 10.1242/jcs.260337] [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: 06/14/2022] [Accepted: 09/22/2023] [Indexed: 10/11/2023] Open
Abstract
Connections between the nucleus and the cytoskeleton are important for positioning and division of the nucleus. In most eukaryotes, the linker of nucleoskeleton and cytoskeleton (LINC) complex spans the outer and inner nuclear membranes and connects the nucleus to the cytoskeleton. In opisthokonts, it is composed of Klarsicht, ANC-1 and Syne homology (KASH) domain proteins and Sad1 and UNC-84 (SUN) domain proteins. Given that the nucleus is positioned at the posterior pole of Toxoplasma gondii, we speculated that apicomplexan parasites must have a similar mechanism that integrates the nucleus and the cytoskeleton. Here, we identified three UNC family proteins in the genome of the apicomplexan parasite T. gondii. Whereas the UNC-50 protein TgUNC1 localised to the Golgi and appeared to be not essential for the parasite, the SUN domain protein TgSLP2 showed a diffuse pattern throughout the parasite. The second SUN domain protein, TgSLP1, was expressed in a cell cycle-dependent manner and was localised close to the mitotic spindle and, more detailed, at the kinetochore. We demonstrate that conditional knockout of TgSLP1 leads to failure of nuclear division and loss of centrocone integrity.
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Affiliation(s)
- Mirjam Wagner
- Experimental Parasitology, Department of Veterinary Sciences, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität, LMU, Munich, 82152, Planegg, Germany
| | - Yuan Song
- Experimental Parasitology, Department of Veterinary Sciences, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität, LMU, Munich, 82152, Planegg, Germany
| | - Elena Jiménez-Ruiz
- Experimental Parasitology, Department of Veterinary Sciences, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität, LMU, Munich, 82152, Planegg, Germany
| | - Sonja Härtle
- Department of Veterinary Sciences, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität, LMU, Munich, 82152, Planegg, Germany
| | - Markus Meissner
- Experimental Parasitology, Department of Veterinary Sciences, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität, LMU, Munich, 82152, Planegg, Germany
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9
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Tengganu IF, Arias Padilla LF, Munera Lopez J, Liu J, Brown PT, Murray JM, Hu K. The cortical microtubules of Toxoplasma gondii underlie the helicity of parasite movement. J Cell Sci 2023; 136:jcs261270. [PMID: 37675776 PMCID: PMC10499027 DOI: 10.1242/jcs.261270] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Accepted: 08/04/2023] [Indexed: 09/08/2023] Open
Abstract
Motility is essential for apicomplexan parasites to infect their hosts. In a three-dimensional (3D) environment, the apicomplexan parasite Toxoplasma gondii moves along a helical path. The cortical microtubules, which are ultra-stable and spirally arranged, have been considered to be a structure that guides the long-distance movement of the parasite. Here, we address the role of the cortical microtubules in parasite motility, invasion and egress by utilizing a previously generated mutant (dubbed 'TKO') in which these microtubules are destabilized in mature parasites. We found that the cortical microtubules in ∼80% of the non-dividing (i.e. daughter-free) TKO parasites are much shorter than normal. The extent of depolymerization was further exacerbated upon commencement of daughter formation or cold treatment, but parasite replication was not affected. In a 3D Matrigel matrix, the TKO mutant moved directionally over long distances, but along trajectories that were significantly more linear (i.e. less helical) than those of wild-type parasites. Interestingly, this change in trajectory did not impact either movement speed in the matrix or the speed and behavior of the parasite during entry into and egress from the host cell.
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Affiliation(s)
- Isadonna F. Tengganu
- Biodesign Center for Mechanisms of Evolution/School of Life Sciences, Arizona State University, Tempe, AZ 85284, USA
| | - Luisa F. Arias Padilla
- Biodesign Center for Mechanisms of Evolution/School of Life Sciences, Arizona State University, Tempe, AZ 85284, USA
| | - Jonathan Munera Lopez
- Biodesign Center for Mechanisms of Evolution/School of Life Sciences, Arizona State University, Tempe, AZ 85284, USA
| | - Jun Liu
- Department of Biology, Indiana University, Bloomington, ID 47405, USA
| | - Peter T. Brown
- Department of Physics and Center for Biological Physics, Arizona State University, Tempe, AZ 85284, USA
| | - John M. Murray
- Biodesign Center for Mechanisms of Evolution/School of Life Sciences, Arizona State University, Tempe, AZ 85284, USA
| | - Ke Hu
- Biodesign Center for Mechanisms of Evolution/School of Life Sciences, Arizona State University, Tempe, AZ 85284, USA
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10
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Hvorecny KL, Sladewski TE, De La Cruz EM, Kollman JM, Heaslip AT. Toxoplasma gondii actin filaments are tuned for rapid disassembly and turnover. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.29.555340. [PMID: 37693530 PMCID: PMC10491163 DOI: 10.1101/2023.08.29.555340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
The cytoskeletal protein actin plays a critical role in the pathogenicity of Toxoplasma gondii, mediating invasion and egress, cargo transport, and organelle inheritance. Advances in live cell imaging have revealed extensive filamentous actin networks in the Apicomplexan parasite, but there is conflicting data regarding the biochemical and biophysical properties of Toxoplasma actin. Here, we imaged the in vitro assembly of individual Toxoplasma actin filaments in real time, showing that native, unstabilized filaments grow tens of microns in length. Unlike skeletal muscle actin, Toxoplasma filaments intrinsically undergo rapid treadmilling due to a high critical concentration, fast monomer dissociation, and rapid nucleotide exchange. Cryo-EM structures of stabilized and unstabilized filaments show an architecture like skeletal actin, with differences in assembly contacts in the D-loop that explain the dynamic nature of the filament, likely a conserved feature of Apicomplexan actin. This work demonstrates that evolutionary changes at assembly interfaces can tune dynamic properties of actin filaments without disrupting their conserved structure.
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Affiliation(s)
- Kelli L Hvorecny
- Department of Biochemistry, University of Washington, Seattle, WA, USA
| | - Thomas E Sladewski
- Department of Department of Molecular and Cell Biology, University of Connecticut, Storrs, Connecticut, USA
| | - Enrique M De La Cruz
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520
| | - Justin M Kollman
- Department of Biochemistry, University of Washington, Seattle, WA, USA
| | - Aoife T Heaslip
- Department of Department of Molecular and Cell Biology, University of Connecticut, Storrs, Connecticut, USA
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11
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Martinez M, Mageswaran SK, Guérin A, Chen WD, Thompson CP, Chavin S, Soldati-Favre D, Striepen B, Chang YW. Origin and arrangement of actin filaments for gliding motility in apicomplexan parasites revealed by cryo-electron tomography. Nat Commun 2023; 14:4800. [PMID: 37558667 PMCID: PMC10412601 DOI: 10.1038/s41467-023-40520-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Accepted: 07/26/2023] [Indexed: 08/11/2023] Open
Abstract
The phylum Apicomplexa comprises important eukaryotic parasites that invade host tissues and cells using a unique mechanism of gliding motility. Gliding is powered by actomyosin motors that translocate host-attached surface adhesins along the parasite cell body. Actin filaments (F-actin) generated by Formin1 play a central role in this critical parasitic activity. However, their subcellular origin, path and ultrastructural arrangement are poorly understood. Here we used cryo-electron tomography to image motile Cryptosporidium parvum sporozoites and reveal the cellular architecture of F-actin at nanometer-scale resolution. We demonstrate that F-actin nucleates at the apically positioned preconoidal rings and is channeled into the pellicular space between the parasite plasma membrane and the inner membrane complex in a conoid extrusion-dependent manner. Within the pellicular space, filaments on the inner membrane complex surface appear to guide the apico-basal flux of F-actin. F-actin concordantly accumulates at the basal end of the parasite. Finally, analyzing a Formin1-depleted Toxoplasma gondii mutant pinpoints the upper preconoidal ring as the conserved nucleation hub for F-actin in Cryptosporidium and Toxoplasma. Together, we provide an ultrastructural model for the life cycle of F-actin for apicomplexan gliding motility.
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Affiliation(s)
- Matthew Martinez
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Shrawan Kumar Mageswaran
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Institute of Structural Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Amandine Guérin
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - William David Chen
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Cameron Parker Thompson
- Pennsylvania Muscle Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Sabine Chavin
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA, USA
| | - Dominique Soldati-Favre
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Boris Striepen
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Yi-Wei Chang
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
- Institute of Structural Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
- Pennsylvania Muscle Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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12
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O’Shaughnessy WJ, Hu X, Henriquez SA, Reese ML. Toxoplasma ERK7 protects the apical complex from premature degradation. J Cell Biol 2023; 222:e202209098. [PMID: 37027006 PMCID: PMC10083718 DOI: 10.1083/jcb.202209098] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Revised: 02/01/2023] [Accepted: 03/17/2023] [Indexed: 04/08/2023] Open
Abstract
Accurate cellular replication balances the biogenesis and turnover of complex structures. In the apicomplexan parasite Toxoplasma gondii, daughter cells form within an intact mother cell, creating additional challenges to ensuring fidelity of division. The apical complex is critical to parasite infectivity and consists of apical secretory organelles and specialized cytoskeletal structures. We previously identified the kinase ERK7 as required for maturation of the apical complex in Toxoplasma. Here, we define the Toxoplasma ERK7 interactome, including a putative E3 ligase, CSAR1. Genetic disruption of CSAR1 fully suppresses loss of the apical complex upon ERK7 knockdown. Furthermore, we show that CSAR1 is normally responsible for turnover of maternal cytoskeleton during cytokinesis, and that its aberrant function is driven by mislocalization from the parasite residual body to the apical complex. These data identify a protein homeostasis pathway critical for Toxoplasma replication and fitness and suggest an unappreciated role for the parasite residual body in compartmentalizing processes that threaten the fidelity of parasite development.
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Affiliation(s)
| | - Xiaoyu Hu
- Department of Pharmacology, University of Texas, Southwestern Medical Center, Dallas, TX, USA
| | - Sarah Ana Henriquez
- Department of Pharmacology, University of Texas, Southwestern Medical Center, Dallas, TX, USA
| | - Michael L. Reese
- Department of Pharmacology, University of Texas, Southwestern Medical Center, Dallas, TX, USA
- Department of Biochemistry, University of Texas, Southwestern Medical Center, Dallas, TX, USA
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13
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Koreny L, Mercado-Saavedra BN, Klinger CM, Barylyuk K, Butterworth S, Hirst J, Rivera-Cuevas Y, Zaccai NR, Holzer VJC, Klingl A, Dacks JB, Carruthers VB, Robinson MS, Gras S, Waller RF. Stable endocytic structures navigate the complex pellicle of apicomplexan parasites. Nat Commun 2023; 14:2167. [PMID: 37061511 PMCID: PMC10105704 DOI: 10.1038/s41467-023-37431-x] [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: 07/01/2022] [Accepted: 03/17/2023] [Indexed: 04/17/2023] Open
Abstract
Apicomplexan parasites have immense impacts on humanity, but their basic cellular processes are often poorly understood. Where endocytosis occurs in these cells, how conserved this process is with other eukaryotes, and what the functions of endocytosis are across this phylum are major unanswered questions. Using the apicomplexan model Toxoplasma, we identified the molecular composition and behavior of unusual, fixed endocytic structures. Here, stable complexes of endocytic proteins differ markedly from the dynamic assembly/disassembly of these machineries in other eukaryotes. We identify that these endocytic structures correspond to the 'micropore' that has been observed throughout the Apicomplexa. Moreover, conserved molecular adaptation of this structure is seen in apicomplexans including the kelch-domain protein K13 that is central to malarial drug-resistance. We determine that a dominant function of endocytosis in Toxoplasma is plasma membrane homeostasis, rather than parasite nutrition, and that these specialized endocytic structures originated early in infrakingdom Alveolata likely in response to the complex cell pellicle that defines this medically and ecologically important ancient eukaryotic lineage.
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Affiliation(s)
- Ludek Koreny
- Department of Biochemistry, University of Cambridge, Cambridge, CB2 1QW, UK
| | | | - Christen M Klinger
- Division of Infectious Diseases, Department of Medicine, University of Alberta, Edmonton, AB, T6G 2R3, Canada
| | | | - Simon Butterworth
- Department of Biochemistry, University of Cambridge, Cambridge, CB2 1QW, UK
| | - Jennifer Hirst
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, CB2 1QW, UK
| | - Yolanda Rivera-Cuevas
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - Nathan R Zaccai
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, CB2 1QW, UK
| | - Victoria J C Holzer
- Plant Development, Ludwig-Maximilians-University Munich, Planegg-Martinsried, 82152, Germany
| | - Andreas Klingl
- Plant Development, Ludwig-Maximilians-University Munich, Planegg-Martinsried, 82152, Germany
| | - Joel B Dacks
- Division of Infectious Diseases, Department of Medicine, University of Alberta, Edmonton, AB, T6G 2R3, Canada
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, 370 05, Czech Republic
| | - Vern B Carruthers
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - Margaret S Robinson
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, CB2 1QW, UK
| | - Simon Gras
- Experimental Parasitology, Department for Veterinary Sciences, Ludwig-Maximilians-University Munich, Planegg-Martinsried, 82152, Germany.
| | - Ross F Waller
- Department of Biochemistry, University of Cambridge, Cambridge, CB2 1QW, UK.
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14
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Dans MG, Piirainen H, Nguyen W, Khurana S, Mehra S, Razook Z, Geoghegan ND, Dawson AT, Das S, Parkyn Schneider M, Jonsdottir TK, Gabriela M, Gancheva MR, Tonkin CJ, Mollard V, Goodman CD, McFadden GI, Wilson DW, Rogers KL, Barry AE, Crabb BS, de Koning-Ward TF, Sleebs BE, Kursula I, Gilson PR. Sulfonylpiperazine compounds prevent Plasmodium falciparum invasion of red blood cells through interference with actin-1/profilin dynamics. PLoS Biol 2023; 21:e3002066. [PMID: 37053271 PMCID: PMC10128974 DOI: 10.1371/journal.pbio.3002066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 04/25/2023] [Accepted: 03/06/2023] [Indexed: 04/15/2023] Open
Abstract
With emerging resistance to frontline treatments, it is vital that new antimalarial drugs are identified to target Plasmodium falciparum. We have recently described a compound, MMV020291, as a specific inhibitor of red blood cell (RBC) invasion, and have generated analogues with improved potency. Here, we generated resistance to MMV020291 and performed whole genome sequencing of 3 MMV020291-resistant populations. This revealed 3 nonsynonymous single nucleotide polymorphisms in 2 genes; 2 in profilin (N154Y, K124N) and a third one in actin-1 (M356L). Using CRISPR-Cas9, we engineered these mutations into wild-type parasites, which rendered them resistant to MMV020291. We demonstrate that MMV020291 reduces actin polymerisation that is required by the merozoite stage parasites to invade RBCs. Additionally, the series inhibits the actin-1-dependent process of apicoplast segregation, leading to a delayed death phenotype. In vitro cosedimentation experiments using recombinant P. falciparum proteins indicate that potent MMV020291 analogues disrupt the formation of filamentous actin in the presence of profilin. Altogether, this study identifies the first compound series interfering with the actin-1/profilin interaction in P. falciparum and paves the way for future antimalarial development against the highly dynamic process of actin polymerisation.
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Affiliation(s)
- Madeline G Dans
- Burnet Institute, Melbourne, Victoria, Australia
- School of Medicine and Institute for Mental and Physical Health and Clinical Translation, Deakin University, Waurn Ponds, Victoria, Australia
- Walter and Eliza Hall Institute, Parkville, Victoria, Australia
| | - Henni Piirainen
- Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| | - William Nguyen
- Walter and Eliza Hall Institute, Parkville, Victoria, Australia
| | - Sachin Khurana
- Walter and Eliza Hall Institute, Parkville, Victoria, Australia
| | - Somya Mehra
- Burnet Institute, Melbourne, Victoria, Australia
| | - Zahra Razook
- Burnet Institute, Melbourne, Victoria, Australia
- School of Medicine and Institute for Mental and Physical Health and Clinical Translation, Deakin University, Waurn Ponds, Victoria, Australia
| | | | | | - Sujaan Das
- Ludwig Maximilian University, Faculty of Veterinary Medicine, Munich, Germany
| | | | - Thorey K Jonsdottir
- Burnet Institute, Melbourne, Victoria, Australia
- Department of Microbiology and Immunology, The University of Melbourne, Parkville, Victoria, Australia
| | - Mikha Gabriela
- Burnet Institute, Melbourne, Victoria, Australia
- School of Medicine and Institute for Mental and Physical Health and Clinical Translation, Deakin University, Waurn Ponds, Victoria, Australia
| | - Maria R Gancheva
- Research Centre for Infectious Diseases, The University of Adelaide, Adelaide, Australia
| | | | - Vanessa Mollard
- School of Biosciences, The University of Melbourne, Parkville, Victoria, Australia
| | | | - Geoffrey I McFadden
- School of Biosciences, The University of Melbourne, Parkville, Victoria, Australia
| | - Danny W Wilson
- Research Centre for Infectious Diseases, The University of Adelaide, Adelaide, Australia
| | - Kelly L Rogers
- Walter and Eliza Hall Institute, Parkville, Victoria, Australia
| | - Alyssa E Barry
- Burnet Institute, Melbourne, Victoria, Australia
- School of Medicine and Institute for Mental and Physical Health and Clinical Translation, Deakin University, Waurn Ponds, Victoria, Australia
| | - Brendan S Crabb
- Burnet Institute, Melbourne, Victoria, Australia
- Department of Microbiology and Immunology, The University of Melbourne, Parkville, Victoria, Australia
| | - Tania F de Koning-Ward
- School of Medicine and Institute for Mental and Physical Health and Clinical Translation, Deakin University, Waurn Ponds, Victoria, Australia
| | - Brad E Sleebs
- Walter and Eliza Hall Institute, Parkville, Victoria, Australia
| | - Inari Kursula
- Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
- Department of Biomedicine, University of Bergen, Bergen, Norway
| | - Paul R Gilson
- Burnet Institute, Melbourne, Victoria, Australia
- Department of Microbiology and Immunology, The University of Melbourne, Parkville, Victoria, Australia
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15
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Burrell A, Marugan-Hernandez V, Graefin Von Der Recke K, Aguiar-Martins K, Gabriel HB, Tomley FM, Vaughan S. Refractile bodies of Eimeria tenella are proteinaceous membrane-less organelles that undergo dynamic changes during infection. Front Cell Infect Microbiol 2023; 13:1082622. [PMID: 37033474 PMCID: PMC10081493 DOI: 10.3389/fcimb.2023.1082622] [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: 10/28/2022] [Accepted: 02/27/2023] [Indexed: 03/11/2023] Open
Abstract
IntroductionRefractile bodies (RB) are large membrane-less organelles (MLO) of unknown function found as a prominent mismatched pair within the sporozoite stages of all species of Eimeria, parasitic coccidian protozoa.MethodsHigh resolution imaging methods including time-lapse live confocal microscopy and serial block face-scanning electron microscopy (SBF-SEM) were used to investigate the morphology of RB and other intracellular organelles before and after sporozoite invasion of host cells.ResultsLive cell imaging of MDBK cells infected with E. tenella sporozoites confirmed previous reports that RB reduce from two to one post-infection and showed that reduction in RB number occurs via merger of the anterior RB with the posterior RB, a process that lasts 20-40 seconds and takes place between 2- and 5-hours post-infection. Ultrastructural studies using SBF-SEM on whole individual sporozoites, both pre- and post-host cell invasion, confirmed the live cell imaging observations and showed also that changes to the overall sporozoite cell shape accompanied RB merger. Furthermore, the single RB post-merger was found to be larger in volume than the two RB pre-merger. Actin inhibitors were used to investigate a potential role for actin in RB merger, Cytochalasin D significantly inhibited both RB merger and the accompanying changes in sporozoite cell shape.DiscussionMLOs in eukaryotic organisms are characterised by their lack of a membrane and ability to undergo liquid-liquid phase separation (LLPS) and fusion, usually in an actin-mediated fashion. Based on the changes in sporozoite cell shape observed at the time of RB merger together with a potential role for actin in this process, we propose that RB are classed as an MLO and recognised as one of the largest MLOs so far characterised.
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Affiliation(s)
- Alana Burrell
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, United Kingdom
- Department of Pathobiology and Population Sciences, The Royal Veterinary College, University of London, North Mymms, United Kingdom
| | - Virginia Marugan-Hernandez
- Department of Pathobiology and Population Sciences, The Royal Veterinary College, University of London, North Mymms, United Kingdom
- *Correspondence: Virginia Marugan-Hernandez, ; Sue Vaughan,
| | - Karolin Graefin Von Der Recke
- Department of Pathobiology and Population Sciences, The Royal Veterinary College, University of London, North Mymms, United Kingdom
| | - Kelsilandia Aguiar-Martins
- Department of Pathobiology and Population Sciences, The Royal Veterinary College, University of London, North Mymms, United Kingdom
| | - Heloisa Berti Gabriel
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, United Kingdom
| | - Fiona M. Tomley
- Department of Pathobiology and Population Sciences, The Royal Veterinary College, University of London, North Mymms, United Kingdom
| | - Sue Vaughan
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, United Kingdom
- *Correspondence: Virginia Marugan-Hernandez, ; Sue Vaughan,
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16
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Haase R, Dos Santos Pacheco N, Soldati-Favre D. Nanoscale imaging of the conoid and functional dissection of its dynamics in Apicomplexa. Curr Opin Microbiol 2022; 70:102226. [PMID: 36332501 DOI: 10.1016/j.mib.2022.102226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 09/27/2022] [Accepted: 10/03/2022] [Indexed: 11/08/2022]
Abstract
Members of the Apicomplexa phylum are unified by an apical complex tailored for motility and host cell invasion. It includes regulated secretory organelles and a conoid attached to the apical polar ring (APR) from which subpellicular microtubules emerge. In coccidia, the conoid is composed of a cone of spiraling tubulin fibers, two preconoidal rings, and two intraconoidal microtubules. The conoid extrudes through the APR in motile parasites. Recent advances in proteomics, cryo-electron tomography, super-resolution, and expansion microscopy provide a more comprehensive view of the spatial and temporal resolution of proteins belonging to the conoid subcomponents. In combination with the phenotyping of targeted mutants, the biogenesis, turnover, dynamics, and function of the conoid begin to be elucidated.
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Affiliation(s)
- Romuald Haase
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, Switzerland
| | - Nicolas Dos Santos Pacheco
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, Switzerland
| | - Dominique Soldati-Favre
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, Switzerland.
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17
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Yee M, Walther T, Frischknecht F, Douglas RG. Divergent Plasmodium actin residues are essential for filament localization, mosquito salivary gland invasion and malaria transmission. PLoS Pathog 2022; 18:e1010779. [PMID: 35998188 PMCID: PMC9439217 DOI: 10.1371/journal.ppat.1010779] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 09/02/2022] [Accepted: 07/29/2022] [Indexed: 11/18/2022] Open
Abstract
Actin is one of the most conserved and ubiquitous proteins in eukaryotes. Its sequence has been highly conserved for its monomers to self-assemble into filaments that mediate essential cell functions such as trafficking, cell shape and motility. The malaria-causing parasite, Plasmodium, expresses a highly sequence divergent actin that is critical for its rapid motility at different stages within its mammalian and mosquito hosts. Each of Plasmodium actin’s four subdomains have divergent regions compared to canonical vertebrate actins. We previously identified subdomains 2 and 3 as providing critical contributions for parasite actin function as these regions could not be replaced by subdomains of vertebrate actins. Here we probed the contributions of individual divergent amino acid residues in these subdomains on parasite motility and progression. Non-lethal changes in these subdomains did not affect parasite development in the mammalian host but strongly affected progression through the mosquito with striking differences in transmission to and through the insect. Live visualization of actin filaments showed that divergent amino acid residues in subdomains 2 and 4 enhanced localization associated with filaments, while those in subdomain 3 negatively affected actin filaments. This suggests that finely tuned actin dynamics are essential for efficient organ entry in the mosquito vector affecting malaria transmission. This work provides residue level insight on the fundamental requirements of actin in highly motile cells. Actin is one of the most abundant and conserved proteins known. Actin monomers can join together to form long filaments. The malaria-causing parasite is transmitted by mosquitoes and needs actin to move very rapidly. An actin from the parasite is different to other actins: its amino acid sequence has relatively high amounts of changes compared to animal species and the actin tends to form only short filaments. We previously identified two large parts of the protein that were critical for the parasite since these large parts could not be exchanged with the equivalent regions of other species. In this study, we focused in on these regions by making more discrete mutations. Most mutations of the actin sequence were tolerated by the parasite in the blood stages. However, these mutants has striking defects in progressing through mosquitoes, especially in invading its salivary glands. We used a new filament labeler to visualize how these mutations affect the actin filaments and found surprisingly different effects. Taken together, small changes to the sequence can have large consequences for the parasite, which ultimately affects its ability to transmit to a new host.
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Affiliation(s)
- Michelle Yee
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
| | - Tobias Walther
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
| | - Friedrich Frischknecht
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
- German Centre for Infection Research, DZIF, partner site Heidelberg, Heidelberg, Germany
- * E-mail: (FF); (RGD)
| | - Ross G. Douglas
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
- Biochemistry and Molecular Biology, Interdisciplinary Research Centre and Molecular Infection Biology, Biomedical Research Centre Seltersberg, Justus Liebig University Giessen, Giessen, Germany
- * E-mail: (FF); (RGD)
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18
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Tsee Dawson A, Tonkin CJ. A CRISPR upgrade unlocks Toxoplasma gene function. Trends Parasitol 2022; 38:826-828. [PMID: 35973902 DOI: 10.1016/j.pt.2022.07.007] [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: 07/22/2022] [Accepted: 07/22/2022] [Indexed: 10/15/2022]
Abstract
Forward genetic screens are invaluable in describing gene function. CRISPR has reinvigorated phenotypic screens in Toxoplasma - a model apicomplexan parasite. Two recent papers by Smith et al. and Li et al. take the next big leap in performing forward genetic screens in Toxoplasma by combining conditional gene regulation with CRISPR.
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Affiliation(s)
- Aurelie Tsee Dawson
- The Division of Infectious Diseases and Immune Defense, The Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, Melbourne, Victoria, Australia; Department of Medical Biology, The University of Melbourne, Parkville, Melbourne, Victoria, Australia
| | - Christopher J Tonkin
- The Division of Infectious Diseases and Immune Defense, The Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, Melbourne, Victoria, Australia; Department of Medical Biology, The University of Melbourne, Parkville, Melbourne, Victoria, Australia.
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19
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Yao H, Zhang L, Yan S, He Y, Zhu H, Li Y, Wang D, Yang K. Low-intensity pulsed ultrasound/nanomechanical force generators enhance osteogenesis of BMSCs through microfilaments and TRPM7. J Nanobiotechnology 2022; 20:378. [PMID: 35964037 PMCID: PMC9375242 DOI: 10.1186/s12951-022-01587-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 08/03/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Low-intensity pulsed ultrasound (LIPUS) has been reported to accelerate fracture healing, but the mechanism is unclear and its efficacy needs to be further optimized. Ultrasound in combination with functionalized microbubbles has been shown to induce local shear forces and controllable mechanical stress in cells, amplifying the mechanical effects of LIPUS. Nanoscale lipid bubbles (nanobubbles) have high stability and good biosafety. However, the effect of LIPUS combined with functionalized nanobubbles on osteogenesis has rarely been studied. RESULTS In this study, we report cyclic arginine-glycine-aspartic acid-modified nanobubbles (cRGD-NBs), with a particle size of ~ 500 nm, able to actively target bone marrow mesenchymal stem cells (BMSCs) via integrin receptors. cRGD-NBs can act as nanomechanical force generators on the cell membrane, and further enhance the BMSCs osteogenesis and bone formation promoted by LIPUS. The polymerization of actin microfilaments and the mechanosensitive transient receptor potential melastatin 7 (TRPM7) ion channel play important roles in BMSCs osteogenesis promoted by LIPUS/cRGD-NBs. Moreover, the mutual regulation of TRPM7 and actin microfilaments promote the effect of LIPUS/cRGD-NBs. The extracellular Ca2 + influx, controlled partly by TRPM7, could participated in the effect of LIPUS/cRGD-NBs on BMSCs. CONCLUSIONS The nanomechanical force generators cRGD-NBs could promote osteogenesis of BMSCs and bone formation induced by LIPUS, through regulation TRPM7, actin cytoskeleton, and intracellular calcium oscillations. This study provides new directions for optimizing the efficacy of LIPUS for fracture healing, and a theoretical basis for the further application and development of LIPUS in clinical practice.
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Affiliation(s)
- Huan Yao
- Pediatric Research Institute, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Engineering Research Center of Stem Cell Therapy, Chongqing, 400014, China.,Department of Ultrasound, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, China
| | - Liang Zhang
- Department of Ultrasound, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, China
| | - Shujin Yan
- Department of Ultrasound, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, China
| | - Yiman He
- Department of Ultrasound, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, China
| | - Hui Zhu
- Department of Ultrasound, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, China
| | - Yasha Li
- Pediatric Research Institute, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Engineering Research Center of Stem Cell Therapy, Chongqing, 400014, China
| | - Dong Wang
- Department of Ultrasound, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, China
| | - Ke Yang
- Pediatric Research Institute, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Engineering Research Center of Stem Cell Therapy, Chongqing, 400014, China.
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20
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Engelberg K, Bechtel T, Michaud C, Weerapana E, Gubbels MJ. Proteomic characterization of the Toxoplasma gondii cytokinesis machinery portrays an expanded hierarchy of its assembly and function. Nat Commun 2022; 13:4644. [PMID: 35941170 PMCID: PMC9360017 DOI: 10.1038/s41467-022-32151-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Accepted: 07/15/2022] [Indexed: 12/01/2022] Open
Abstract
The basal complex (BC) is essential for T. gondii cell division but mechanistic details are lacking. Here we report a reciprocal proximity based biotinylation approach to map the BC’s proteome. We interrogate the resulting map for spatiotemporal dynamics and function by disrupting the expression of components. This highlights four architecturally distinct BC subcomplexes, the compositions of which change dynamically in correlation with changes in BC function. We identify BCC0 as a protein undergirding BC formation in five foci that precede the same symmetry seen in the apical annuli and IMC sutures. Notably, daughter budding from BCC0 progresses bidirectionally: the apical cap in apical and the rest of the IMC in basal direction. Furthermore, the essential role of the BC in cell division is contained in BCC4 and MORN1 that form a ‘rubber band’ to sequester the basal end of the assembling daughter cytoskeleton. Finally, we assign BCC1 to the non-essential, final BC constriction step. The basal complex is orchestrating Toxoplasma gondii cell division steps. Here, the authors use proximity biotinylation to map the proteome of this contractile ring, identify components acting on its formation, stability and constriction, and reveal bidirectional daughter budding.
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Affiliation(s)
| | - Tyler Bechtel
- Department of Chemistry, Boston College, Chestnut Hill, MA, USA
| | - Cynthia Michaud
- Department of Biology, Boston College, Chestnut Hill, MA, USA
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21
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Munera Lopez J, Tengganu IF, Liu J, Murray JM, Arias Padilla LF, Zhang Y, Brown PT, Florens L, Hu K. An apical protein, Pcr2, is required for persistent movement by the human parasite Toxoplasma gondii. PLoS Pathog 2022; 18:e1010776. [PMID: 35994509 PMCID: PMC9436145 DOI: 10.1371/journal.ppat.1010776] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 09/01/2022] [Accepted: 07/28/2022] [Indexed: 11/18/2022] Open
Abstract
The phylum Apicomplexa includes thousands of species of unicellular parasites that cause a wide range of human and animal diseases such as malaria and toxoplasmosis. To infect, the parasite must first initiate active movement to disseminate through tissue and invade into a host cell, and then cease moving once inside. The parasite moves by gliding on a surface, propelled by an internal cortical actomyosin-based motility apparatus. One of the most effective invaders in Apicomplexa is Toxoplasma gondii, which can infect any nucleated cell and any warm-blooded animal. During invasion, the parasite first makes contact with the host cell "head-on" with the apical complex, which features an elaborate cytoskeletal apparatus and associated structures. Here we report the identification and characterization of a new component of the apical complex, Preconoidal region protein 2 (Pcr2). Pcr2 knockout parasites replicate normally, but they are severely diminished in their capacity for host tissue destruction due to significantly impaired invasion and egress, two vital steps in the lytic cycle. When stimulated for calcium-induced egress, Pcr2 knockout parasites become active, and secrete effectors to lyse the host cell. Calcium-induced secretion of the major adhesin, MIC2, also appears to be normal. However, the movement of the Pcr2 knockout parasite is spasmodic, which drastically compromises egress. In addition to faulty motility, the ability of the Pcr2 knockout parasite to assemble the moving junction is impaired. Both defects likely contribute to the poor efficiency of invasion. Interestingly, actomyosin activity, as indicated by the motion of mEmerald tagged actin chromobody, appears to be largely unperturbed by the loss of Pcr2, raising the possibility that Pcr2 may act downstream of or in parallel with the actomyosin machinery.
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Affiliation(s)
- Jonathan Munera Lopez
- Biodesign Center for Mechanisms of Evolution/School of Life Sciences, Arizona State University, Tempe, Arizona, United States of America
| | - Isadonna F. Tengganu
- Biodesign Center for Mechanisms of Evolution/School of Life Sciences, Arizona State University, Tempe, Arizona, United States of America
| | - Jun Liu
- Department of Biology, Indiana University, Bloomington, Indiana, United States of America
| | - John M. Murray
- Biodesign Center for Mechanisms of Evolution/School of Life Sciences, Arizona State University, Tempe, Arizona, United States of America
| | - Luisa F. Arias Padilla
- Biodesign Center for Mechanisms of Evolution/School of Life Sciences, Arizona State University, Tempe, Arizona, United States of America
| | - Ying Zhang
- Stowers Institute for Medical Research, Kansas City, Missouri, United States of America
| | - Peter T. Brown
- Department of Physics and Center for Biological Physics, Arizona State University, Tempe, Arizona, United States of America
| | - Laurence Florens
- Stowers Institute for Medical Research, Kansas City, Missouri, United States of America
| | - Ke Hu
- Biodesign Center for Mechanisms of Evolution/School of Life Sciences, Arizona State University, Tempe, Arizona, United States of America
- * E-mail:
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22
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Kent RS, Briggs EM, Colon BL, Alvarez C, Silva Pereira S, De Niz M. Paving the Way: Contributions of Big Data to Apicomplexan and Kinetoplastid Research. Front Cell Infect Microbiol 2022; 12:900878. [PMID: 35734575 PMCID: PMC9207352 DOI: 10.3389/fcimb.2022.900878] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 05/06/2022] [Indexed: 11/13/2022] Open
Abstract
In the age of big data an important question is how to ensure we make the most out of the resources we generate. In this review, we discuss the major methods used in Apicomplexan and Kinetoplastid research to produce big datasets and advance our understanding of Plasmodium, Toxoplasma, Cryptosporidium, Trypanosoma and Leishmania biology. We debate the benefits and limitations of the current technologies, and propose future advancements that may be key to improving our use of these techniques. Finally, we consider the difficulties the field faces when trying to make the most of the abundance of data that has already been, and will continue to be, generated.
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Affiliation(s)
- Robyn S. Kent
- Department of Microbiology and Molecular Genetics, University of Vermont, Burlington, VT, United States
| | - Emma M. Briggs
- Institute for Immunology and Infection Research, School of Biological Sciences, University Edinburgh, Edinburgh, United Kingdom
- Wellcome Centre for Integrative Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, United Kingdom
| | - Beatrice L. Colon
- Wellcome Centre for Anti-Infectives Research, Division of Biological Chemistry and Drug Discovery, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Catalina Alvarez
- de Duve Institute, Université Catholique de Louvain, Brussels, Belgium
| | - Sara Silva Pereira
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina da Universidade de Lisboa, Lisboa, Portugal
| | - Mariana De Niz
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina da Universidade de Lisboa, Lisboa, Portugal
- Institut Pasteur, Paris, France
- *Correspondence: Mariana De Niz,
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Li W, Grech J, Stortz JF, Gow M, Periz J, Meissner M, Jimenez-Ruiz E. A splitCas9 phenotypic screen in Toxoplasma gondii identifies proteins involved in host cell egress and invasion. Nat Microbiol 2022; 7:882-895. [PMID: 35538310 DOI: 10.1038/s41564-022-01114-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 03/31/2022] [Indexed: 11/09/2022]
Abstract
Apicomplexan parasites, such as Toxoplasma gondii, have specific adaptations that enable invasion and exit from the host cell. Owing to the phylogenetic distance between apicomplexan parasites and model organisms, comparative genomics has limited capacity to infer gene functions. Further, although CRISPR/Cas9-based screens have assigned roles to some Toxoplasma genes, the functions of encoded proteins have proven difficult to assign. To overcome this problem, we devised a conditional Cas9-system in T. gondii that enables phenotypic screens. Using an indicator strain for F-actin dynamics and apicoplast segregation, we screened 320 genes to identify those required for defined steps in the asexual life cycle. The detailed characterization of two genes identified in our screen, through the generation of conditional knockout parasites using the DiCre-system, revealed that signalling linking factor (SLF) is an integral part of a signalling complex required for early induction of egress, and a novel conoid protein (conoid gliding protein, CGP) functions late during egress and is required for the activation of gliding motility. Establishing different indicator lines and applying our conditional Cas9 screen could enable the identification of genes involved in organellar biogenesis, parasite replication or maintenance of the endosymbiotic organelles in the future.
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Affiliation(s)
- Wei Li
- Experimental Parasitology, Department of Veterinary Sciences, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität, LMU, Munich, Germany
| | - Janessa Grech
- Experimental Parasitology, Department of Veterinary Sciences, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität, LMU, Munich, Germany
| | - Johannes Felix Stortz
- Wellcome Centre for Integrative Parasitology, Institute of Infection, Immunity and Inflammation, Glasgow Biomedical Research Centre, University of Glasgow, Glasgow, UK.,Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Matthew Gow
- Experimental Parasitology, Department of Veterinary Sciences, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität, LMU, Munich, Germany
| | - Javier Periz
- Experimental Parasitology, Department of Veterinary Sciences, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität, LMU, Munich, Germany
| | - Markus Meissner
- Experimental Parasitology, Department of Veterinary Sciences, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität, LMU, Munich, Germany. .,Wellcome Centre for Integrative Parasitology, Institute of Infection, Immunity and Inflammation, Glasgow Biomedical Research Centre, University of Glasgow, Glasgow, UK.
| | - Elena Jimenez-Ruiz
- Experimental Parasitology, Department of Veterinary Sciences, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität, LMU, Munich, Germany.
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Gubbels MJ, Ferguson DJP, Saha S, Romano JD, Chavan S, Primo VA, Michaud C, Coppens I, Engelberg K. Toxoplasma gondii’s Basal Complex: The Other Apicomplexan Business End Is Multifunctional. Front Cell Infect Microbiol 2022; 12:882166. [PMID: 35573773 PMCID: PMC9103881 DOI: 10.3389/fcimb.2022.882166] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 03/30/2022] [Indexed: 01/08/2023] Open
Abstract
The Apicomplexa are famously named for their apical complex, a constellation of organelles at their apical end dedicated to invasion of their host cells. In contrast, at the other end of the cell, the basal complex (BC) has been overshadowed since it is much less prominent and specific functions were not immediately obvious. However, in the past decade a staggering array of functions have been associated with the BC and strides have been made in understanding its structure. Here, these collective insights are supplemented with new data to provide an overview of the understanding of the BC in Toxoplasma gondii. The emerging picture is that the BC is a dynamic and multifunctional complex, with a series of (putative) functions. The BC has multiple roles in cell division: it is the site where building blocks are added to the cytoskeleton scaffold; it exerts a two-step stretch and constriction mechanism as contractile ring; and it is key in organelle division. Furthermore, the BC has numerous putative roles in ‘import’, such as the recycling of mother cell remnants, the acquisition of host-derived vesicles, possibly the uptake of lipids derived from the extracellular medium, and the endocytosis of micronemal proteins. The latter process ties the BC to motility, whereas an additional role in motility is conferred by Myosin C. Furthermore, the BC acts on the assembly and/or function of the intravacuolar network, which may directly or indirectly contribute to the establishment of chronic tissue cysts. Here we provide experimental support for molecules acting in several of these processes and identify several new BC proteins critical to maintaining the cytoplasmic bridge between divided parasites. However, the dispensable nature of many BC components leaves many questions unanswered regarding its function. In conclusion, the BC in T. gondii is a dynamic and multifunctional structure at the posterior end of the parasite.
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Affiliation(s)
- Marc-Jan Gubbels
- Department of Biology, Boston College, Chestnut Hill, MA, United States
- *Correspondence: Marc-Jan Gubbels, ; Klemens Engelberg,
| | - David J. P. Ferguson
- Nuffield Department of Clinical Laboratory Science, University of Oxford John Radcliffe Hospital, Oxford, United Kingdom
- Department of Biological and Medical Sciences, Faculty of Health and Life Science, Oxford Brookes University, Oxford, United Kingdom
| | - Sudeshna Saha
- Department of Biology, Boston College, Chestnut Hill, MA, United States
| | - Julia D. Romano
- Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, United States
| | - Suyog Chavan
- Department of Biology, Boston College, Chestnut Hill, MA, United States
| | - Vincent A. Primo
- Department of Biology, Boston College, Chestnut Hill, MA, United States
| | - Cynthia Michaud
- Department of Biology, Boston College, Chestnut Hill, MA, United States
| | - Isabelle Coppens
- Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, United States
| | - Klemens Engelberg
- Department of Biology, Boston College, Chestnut Hill, MA, United States
- *Correspondence: Marc-Jan Gubbels, ; Klemens Engelberg,
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25
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Steele-Ogus MC, Obenaus AM, Sniadecki NJ, Paredez AR. Disc and Actin Associated Protein 1 influences attachment in the intestinal parasite Giardia lamblia. PLoS Pathog 2022; 18:e1010433. [PMID: 35333908 PMCID: PMC8986099 DOI: 10.1371/journal.ppat.1010433] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 04/06/2022] [Accepted: 03/10/2022] [Indexed: 02/01/2023] Open
Abstract
The deep-branching eukaryote Giardia lamblia is an extracellular parasite that attaches to the host intestine via a microtubule-based structure called the ventral disc. Control of attachment is mediated in part by the movement of two regions of the ventral disc that either permit or exclude the passage of fluid under the disc. Several known disc-associated proteins (DAPs) contribute to disc structure and function, but no force-generating protein has been identified among them. We recently identified several Giardia actin (GlActin) interacting proteins at the ventral disc, which could potentially employ actin polymerization for force generation and disc conformational changes. One of these proteins, Disc and Actin Associated Protein 1 (DAAP1), is highly enriched at the two regions of the disc previously shown to be important for fluid flow during attachment. In this study, we investigate the role of both GlActin and DAAP1 in ventral disc morphology and function. We confirmed interaction between GlActin and DAAP1 through coimmunoprecipitation, and used immunofluorescence to localize both proteins throughout the cell cycle and during trophozoite attachment. Similar to other DAPs, the association of DAAP1 with the disc is stable, except during cell division when the disc disassembles. Depletion of GlActin by translation-blocking antisense morpholinos resulted in both impaired attachment and defects in the ventral disc, indicating that GlActin contributes to disc-mediated attachment. Depletion of DAAP1 through CRISPR interference resulted in intact discs but impaired attachment, gating, and flow under the disc. As attachment is essential for infection, elucidation of these and other molecular mediators is a promising area for development of new therapeutics against a ubiquitous parasite.
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Affiliation(s)
- Melissa C. Steele-Ogus
- Department of Biology, University of Washington, Seattle, Washington, United States of America
| | - Ava M. Obenaus
- Department of Mechanical Engineering, University of Washington, Seattle, Washington, United States of America
| | - Nathan J. Sniadecki
- Department of Mechanical Engineering, University of Washington, Seattle, Washington, United States of America
| | - Alexander R. Paredez
- Department of Biology, University of Washington, Seattle, Washington, United States of America
- * E-mail:
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26
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Wu RZ, Zhou HY, Song JF, Xia QH, Hu W, Mou XD, Li X. Chemotherapeutics for Toxoplasma gondii: Molecular Biotargets, Binding Modes, and Structure-Activity Relationship Investigations. J Med Chem 2021; 64:17627-17655. [PMID: 34894691 DOI: 10.1021/acs.jmedchem.1c01569] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Toxoplasmosis, an infectious zoonotic disease caused by the apicomplexan parasite Toxoplasma gondii (T. gondii), is a major worldwide health problem. However, there are currently no effective options (chemotherapeutic drugs or prophylactic vaccines) for treating chronic latent toxoplasmosis infection. Accordingly, seeking more effective and safer chemotherapeutics for combating this disease remains a long-term and challenging objective. In this paper, we summarize possible molecular biotargets, with an emphasis on those that are druggable and promising, including, without limitation, calcium-dependent protein kinase 1, bifunctional thymidylate synthase-dihydrofolate reductase, and farnesyl diphosphate synthase. Meanwhile, as important components of medicinal chemistry, the binding modes and structure-activity relationship profiles of the corresponding inhibitors were also illuminated. We anticipate that this information will be helpful for further identification of more effective chemotherapeutic interventions to prevent and treat zoonotic infections caused by T. gondii.
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Affiliation(s)
- Rong-Zhen Wu
- Institute of Materia Medica, Shandong First Medical University and Shandong Academy of Medical Sciences, no. 6699 Qingdao Road, Ji'nan, Shandong 250117, PR China
| | - Huai-Yu Zhou
- Department of Pathogen Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, no. 44 Wenhua Xi Road, Ji'nan, Shandong 250012, PR China
| | - Jing-Feng Song
- School of Pharmaceutical Sciences and Yunnan Provincial Key Laboratory of Pharmacology for Natural Products, Kunming Medical University, no. 1168 Chunrong Xi Road, Kunming, Yunnan 650500, PR China
| | - Qiao-Hong Xia
- Department of Pathogen Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, no. 44 Wenhua Xi Road, Ji'nan, Shandong 250012, PR China
| | - Wei Hu
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, no. 72 Binhai Road of JiMo, Qingdao, Shandong 266237, PR China
| | - Xiao-Dong Mou
- Institute of Materia Medica, Shandong First Medical University and Shandong Academy of Medical Sciences, no. 6699 Qingdao Road, Ji'nan, Shandong 250117, PR China
| | - Xun Li
- Institute of Materia Medica, Shandong First Medical University and Shandong Academy of Medical Sciences, no. 6699 Qingdao Road, Ji'nan, Shandong 250117, PR China.,Key Laboratory of Forensic Toxicology, Ministry of Public Security, Beijing 100192, PR China
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27
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Wagner TR, Rothbauer U. Nanobodies - Little helpers unravelling intracellular signaling. Free Radic Biol Med 2021; 176:46-61. [PMID: 34536541 DOI: 10.1016/j.freeradbiomed.2021.09.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 08/26/2021] [Accepted: 09/08/2021] [Indexed: 11/21/2022]
Abstract
The identification of diagnostic and therapeutic targets requires a comprehensive understanding of cellular processes, for which advanced technologies in biomedical research are needed. The emergence of nanobodies (Nbs) derived from antibody fragments of camelid heavy chain-only antibodies as intracellular research tools offers new possibilities to study and modulate target antigens in living cells. Here we summarize this rapidly changing field, beginning with a brief introduction of Nbs, followed by an overview of how target-specific Nbs can be generated, and introduce the selection of intrabodies as research tools. Intrabodies, by definition, are intracellular functional Nbs that target ectopic or endogenous intracellular antigens within living cells. Such binders can be applied in various formats, e.g. as chromobodies for live cell microscopy or as biosensors to decipher complex intracellular signaling pathways. In addition, protein knockouts can be achieved by target-specific Nbs, while modulating Nbs have the potential as future therapeutics. The development of fine-tunable and switchable Nb-based systems that simultaneously provide spatial and temporal control has recently taken the application of these binders to the next level.
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Affiliation(s)
- Teresa R Wagner
- Pharmaceutical Biotechnology, Eberhard Karls University, Tübingen, Germany; NMI Natural and Medical Sciences Institute at the University of Tübingen, Reutlingen, Germany
| | - Ulrich Rothbauer
- Pharmaceutical Biotechnology, Eberhard Karls University, Tübingen, Germany; NMI Natural and Medical Sciences Institute at the University of Tübingen, Reutlingen, Germany; Cluster of Excellence iFIT (EXC2180) "Image-Guided and Functionally Instructed Tumor Therapies", Eberhard Karls University, Tübingen, Germany.
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28
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Abstract
Apicomplexan parasites, such as Toxoplasma gondii and Plasmodium falciparum, are the cause of many important human and animal diseases. While T. gondii tachyzoites replicate through endodyogeny, during which two daughter cells are formed within the parental cell, P. falciparum replicates through schizogony, where up to 32 parasites are formed in a single infected red blood cell and even thousands of daughter cells during mosquito- or liver-stage development. These processes require a tightly orchestrated division and distribution over the daughter parasites of one-per-cell organelles such as the mitochondrion and apicoplast. Although proper organelle segregation is highly essential, the molecular mechanism and the key proteins involved remain largely unknown. In this review, we describe organelle dynamics during cell division in T. gondii and P. falciparum, summarize the current understanding of the molecular mechanisms underlying organelle fission in these parasites, and introduce candidate fission proteins.
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Abstract
Robert Insall introduces the cytoskeleton special issue and summarises some recent changes in our view of actin function and regulation.
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Affiliation(s)
- Robert Insall
- Institute of Cancer Sciences, University of Glasgow, Garscube Campus, Switchback Road, Bearsden, Glasgow G61 1QH, UK; Cancer Research UK Beatson Institute, Switchback Road, Bearsden, Glasgow G61 1BD, UK.
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30
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Das S, Stortz JF, Meissner M, Periz J. The multiple functions of actin in apicomplexan parasites. Cell Microbiol 2021; 23:e13345. [PMID: 33885206 DOI: 10.1111/cmi.13345] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 03/30/2021] [Accepted: 03/31/2021] [Indexed: 11/29/2022]
Abstract
The cytoskeletal protein actin is highly abundant and conserved in eukaryotic cells. It occurs in two different states- the globular (G-actin) form, which can polymerise into the filamentous (F-actin) form, fulfilling various critical functions including cytokinesis, cargo trafficking and cellular motility. In higher eukaryotes, there are several actin isoforms with nearly identical amino acid sequences. Despite the high level of amino acid identity, they display regulated expression patterns and unique non-redundant roles. The number of actin isoforms together with conserved sequences may reflect the selective pressure exerted by scores of actin binding proteins (ABPs) in higher eukaryotes. In contrast, in many protozoans such as apicomplexan parasites which possess only a few ABPs, the regulatory control of actin and its multiple functions are still obscure. Here, we provide a summary of the regulation and biological functions of actin in higher eukaryotes and compare it with the current knowledge in apicomplexans. We discuss future experiments that will help us understand the multiple, critical roles of this fascinating system in apicomplexans.
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Affiliation(s)
- Sujaan Das
- Faculty of Veterinary Medicine, Experimental Parasitology, Ludwig Maximilian University, Munich, Germany
| | - Johannes Felix Stortz
- Department Metabolism of Infection, Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Markus Meissner
- Faculty of Veterinary Medicine, Experimental Parasitology, Ludwig Maximilian University, Munich, Germany
| | - Javier Periz
- Faculty of Veterinary Medicine, Experimental Parasitology, Ludwig Maximilian University, Munich, Germany
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31
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Abstract
Toxoplasma gondii causes a chronic infection that renders the immunocompromised human host susceptible to toxoplasmic encephalitis triggered by cyst reactivation in the central nervous system. The dense granule protein GRA12 is a major parasite virulence factor required for parasite survival during acute infection. Here, we characterized the role of four GRA12-related genes in acute and chronic stages of infection. While GRA12A, GRA12B, and GRA12D were highly expressed in asexual stage tachyzoites and bradyzoites, expression of GRA12C appeared to be restricted to the sexual stages. In contrast to deletion of GRA12 (Δgra12), no major defects in acute virulence were observed in Δgra12A, Δgra12B, or Δgra12D parasites, though Δgra12B parasites exhibited an increased tachyzoite replication rate. Bradyzoites secreted GRA12A, GRA12B, and GRA12D and incorporated these molecules into the developing cyst wall, as well as the cyst matrix in distinct patterns. Similar to GRA12, GRA12A, GRA12B, and GRA12D colocalized with the dense granules in extracellular tachyzoites, with GRA2 and the intravacuolar network in the tachyzoite stage parasitophorous vacuole and with GRA2 in the cyst matrix and cyst wall. Chronic stage cyst burdens were decreased in mice infected with Δgra12A parasites and were increased in mice infected with Δgra12B parasites. However, Δgra12B cysts were not efficiently maintained in vivo Δgra12A, Δgra12B, and Δgra12D in vitro cysts displayed a reduced reactivation efficiency, and reactivation of Δgra12A cysts was delayed. Collectively, our results suggest that a family of genes related to GRA12 play significant roles in the formation, maintenance, and reactivation of chronic stage cysts.IMPORTANCE If host immunity weakens, Toxoplasma gondii cysts recrudesce in the central nervous system and cause a severe toxoplasmic encephalitis. Current therapies target acute stage infection but do not eliminate chronic cysts. Parasite molecules that mediate the development and persistence of chronic infection are poorly characterized. Dense granule (GRA) proteins such as GRA12 are key virulence factors during acute infection. Here, we investigated four GRA12-related genes. GRA12-related genes were not major virulence factors during acute infection. Instead, GRA12-related proteins localized at the cyst wall and cyst matrix and played significant roles in cyst development, persistence, and reactivation during chronic infection. Similar to GRA12, the GRA12-related proteins selectively associated with the intravacuolar network of membranes inside the vacuole. Collectively, our results support the hypothesis that GRA12 proteins associated with the intravacuolar membrane system support parasite virulence during acute infection and cyst development, persistence, and reactivation during chronic infection.
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32
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Morano AA, Dvorin JD. The Ringleaders: Understanding the Apicomplexan Basal Complex Through Comparison to Established Contractile Ring Systems. Front Cell Infect Microbiol 2021; 11:656976. [PMID: 33954122 PMCID: PMC8089483 DOI: 10.3389/fcimb.2021.656976] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 03/19/2021] [Indexed: 12/02/2022] Open
Abstract
The actomyosin contractile ring is a key feature of eukaryotic cytokinesis, conserved across many eukaryotic kingdoms. Recent research into the cell biology of the divergent eukaryotic clade Apicomplexa has revealed a contractile ring structure required for asexual division in the medically relevant genera Toxoplasma and Plasmodium; however, the structure of the contractile ring, known as the basal complex in these parasites, remains poorly characterized and in the absence of a myosin II homolog, it is unclear how the force required of a cytokinetic contractile ring is generated. Here, we review the literature on the basal complex in Apicomplexans, summarizing what is known about its formation and function, and attempt to provide possible answers to this question and suggest new avenues of study by comparing the Apicomplexan basal complex to well-studied, established cytokinetic contractile rings and their mechanisms in organisms such as S. cerevisiae and D. melanogaster. We also compare the basal complex to structures formed during mitochondrial and plastid division and cytokinetic mechanisms of organisms beyond the Opisthokonts, considering Apicomplexan diversity and divergence.
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Affiliation(s)
- Alexander A Morano
- Biological and Biomedical Sciences, Harvard Medical School, Boston, MA, United States.,Division of Infectious Diseases, Boston Children's Hospital, Boston, MA, United States
| | - Jeffrey D Dvorin
- Division of Infectious Diseases, Boston Children's Hospital, Boston, MA, United States.,Department of Pediatrics, Harvard Medical School, Boston, MA, United States
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Carmeille R, Schiano Lomoriello P, Devarakonda PM, Kellermeier JA, Heaslip AT. Actin and an unconventional myosin motor, TgMyoF, control the organization and dynamics of the endomembrane network in Toxoplasma gondii. PLoS Pathog 2021; 17:e1008787. [PMID: 33529198 PMCID: PMC7880465 DOI: 10.1371/journal.ppat.1008787] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 02/12/2021] [Accepted: 01/07/2021] [Indexed: 12/25/2022] Open
Abstract
Toxoplasma gondii is an obligate intracellular parasite that relies on three distinct secretory organelles, the micronemes, rhoptries, and dense granules, for parasite survival and disease pathogenesis. Secretory proteins destined for these organelles are synthesized in the endoplasmic reticulum (ER) and sequentially trafficked through a highly polarized endomembrane network that consists of the Golgi and multiple post-Golgi compartments. Currently, little is known about how the parasite cytoskeleton controls the positioning of the organelles in this pathway, or how vesicular cargo is trafficked between organelles. Here we show that F-actin and an unconventional myosin motor, TgMyoF, control the dynamics and organization of the organelles in the secretory pathway, specifically ER tubule movement, apical positioning of the Golgi and post-Golgi compartments, apical positioning of the rhoptries, and finally, the directed transport of Rab6-positive and Rop1-positive vesicles. Thus, this study identifies TgMyoF and actin as the key cytoskeletal components that organize the endomembrane system in T. gondii. Endomembrane trafficking is a vital cellular process in all eukaryotic cells. In most cases the molecular motors myosin, kinesin, and dynein transport cargo including vesicles, organelles and transcripts along actin and microtubule filaments in a manner analogous to a train moving on its tracks. For the unicellular eukaryote Toxoplasma gondii, the accurate trafficking of proteins through the endomembrane system is vital for parasite survival and pathogenicity. However, the mechanisms of cargo transport in this parasite are poorly understood. In this study, we fluorescently labeled multiple endomembrane organelles and imaged their movements using live cell microscopy. We demonstrate that filamentous actin and an unconventional myosin motor named TgMyoF control both the positioning of organelles in this pathway and the movement of transport vesicles throughout the parasite cytosol. This data provides new insight into the mechanisms of cargo transport in this important pathogen and expands our understanding of the biological roles of actin in the intracellular phase of the parasite’s growth cycle.
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Affiliation(s)
- Romain Carmeille
- Department of Cell and Molecular Biology, University of Connecticut, Storrs, Connecticut, United States of America
| | - Porfirio Schiano Lomoriello
- Department of Cell and Molecular Biology, University of Connecticut, Storrs, Connecticut, United States of America
| | - Parvathi M. Devarakonda
- Department of Cell and Molecular Biology, University of Connecticut, Storrs, Connecticut, United States of America
| | - Jacob A. Kellermeier
- Department of Cell and Molecular Biology, University of Connecticut, Storrs, Connecticut, United States of America
| | - Aoife T. Heaslip
- Department of Cell and Molecular Biology, University of Connecticut, Storrs, Connecticut, United States of America
- * E-mail:
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34
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Soetens E, Ballegeer M, Saelens X. An Inside Job: Applications of Intracellular Single Domain Antibodies. Biomolecules 2020; 10:biom10121663. [PMID: 33322697 PMCID: PMC7764588 DOI: 10.3390/biom10121663] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 12/09/2020] [Accepted: 12/10/2020] [Indexed: 02/06/2023] Open
Abstract
Sera of camelid species contain a special kind of antibody that consists only of heavy chains. The variable antigen binding domain of these heavy chain antibodies can be expressed as a separate entity, called a single domain antibody that is characterized by its small size, high solubility and oftentimes exceptional stability. Because of this, most single domain antibodies fold correctly when expressed in the reducing environment of the cytoplasm, and thereby retain their antigen binding specificity. Single domain antibodies can thus be used to target a broad range of intracellular proteins. Such intracellular single domain antibodies are also known as intrabodies, and have proven to be highly useful tools for basic research by allowing visualization, disruption and even targeted degradation of intracellular proteins. Furthermore, intrabodies can be used to uncover prospective new therapeutic targets and have the potential to be applied in therapeutic settings in the future. In this review we provide a brief overview of recent advances in the field of intracellular single domain antibodies, focusing on their use as research tools and potential therapeutic applications. Special attention is given to the available methods that allow delivery of single domain antibodies into cells.
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Affiliation(s)
- Eline Soetens
- VIB-UGent Center for Medical Biotechnology, VIB, B-9052 Ghent, Belgium; (E.S.); (M.B.)
- Department of Biochemistry and Microbiology, Ghent University, B-9000 Ghent, Belgium
| | - Marlies Ballegeer
- VIB-UGent Center for Medical Biotechnology, VIB, B-9052 Ghent, Belgium; (E.S.); (M.B.)
- Department of Biochemistry and Microbiology, Ghent University, B-9000 Ghent, Belgium
| | - Xavier Saelens
- VIB-UGent Center for Medical Biotechnology, VIB, B-9052 Ghent, Belgium; (E.S.); (M.B.)
- Department of Biochemistry and Microbiology, Ghent University, B-9000 Ghent, Belgium
- Correspondence:
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35
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Abstract
Mitogen-activated protein kinases (MAPKs) are a conserved family of protein kinases that regulate signal transduction, proliferation, and development throughout eukaryotes. The apicomplexan parasite Toxoplasma gondii expresses three MAPKs. Two of these, extracellular signal-regulated kinase 7 (ERK7) and MAPKL1, have been implicated in the regulation of conoid biogenesis and centrosome duplication, respectively. The third kinase, MAPK2, is specific to and conserved throughout the Alveolata, although its function is unknown. We used the auxin-inducible degron system to determine phenotypes associated with MAPK2 loss of function in Toxoplasma We observed that parasites lacking MAPK2 failed to duplicate their centrosomes and therefore did not initiate daughter cell budding, which ultimately led to parasite death. MAPK2-deficient parasites initiated but did not complete DNA replication and arrested prior to mitosis. Surprisingly, the parasites continued to grow and replicate their Golgi apparatus, mitochondria, and apicoplasts. We found that the failure in centrosome duplication is distinct from the phenotype caused by the depletion of MAPKL1. As we did not observe MAPK2 localization at the centrosome at any point in the cell cycle, our data suggest that MAPK2 regulates a process at a distal site that is required for the completion of centrosome duplication and the initiation of parasite mitosis.IMPORTANCE Toxoplasma gondii is a ubiquitous intracellular protozoan parasite that can cause severe and fatal disease in immunocompromised patients and the developing fetus. Rapid parasite replication is critical for establishing a productive infection. Here, we demonstrate that a Toxoplasma protein kinase called MAPK2 is conserved throughout the Alveolata and essential for parasite replication. We found that parasites lacking MAPK2 protein were defective in the initiation of daughter cell budding and were rendered inviable. Specifically, T. gondii MAPK2 (TgMAPK2) appears to be required for centrosome replication at the basal end of the nucleus, and its loss causes arrest early in parasite division. MAPK2 is unique to the Alveolata and not found in metazoa and likely is a critical component of an essential parasite-specific signaling network.
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36
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de Beer MA, Giepmans BNG. Nanobody-Based Probes for Subcellular Protein Identification and Visualization. Front Cell Neurosci 2020; 14:573278. [PMID: 33240044 PMCID: PMC7667270 DOI: 10.3389/fncel.2020.573278] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 10/05/2020] [Indexed: 12/14/2022] Open
Abstract
Understanding how building blocks of life contribute to physiology is greatly aided by protein identification and cellular localization. The two main labeling approaches developed over the past decades are labeling with antibodies such as immunoglobulin G (IgGs) or use of genetically encoded tags such as fluorescent proteins. However, IgGs are large proteins (150 kDa), which limits penetration depth and uncertainty of target position caused by up to ∼25 nm distance of the label created by the chosen targeting approach. Additionally, IgGs cannot be easily recombinantly modulated and engineered as part of fusion proteins because they consist of multiple independent translated chains. In the last decade single domain antigen binding proteins are being explored in bioscience as a tool in revealing molecular identity and localization to overcome limitations by IgGs. These nanobodies have several potential benefits over routine applications. Because of their small size (15 kDa), nanobodies better penetrate during labeling procedures and improve resolution. Moreover, nanobodies cDNA can easily be fused with other cDNA. Multidomain proteins can thus be easily engineered consisting of domains for targeting (nanobodies) and visualization by fluorescence microscopy (fluorescent proteins) or electron microscopy (based on certain enzymes). Additional modules for e.g., purification are also easily added. These nanobody-based probes can be applied in cells for live-cell endogenous protein detection or may be purified prior to use on molecules, cells or tissues. Here, we present the current state of nanobody-based probes and their implementation in microscopy, including pitfalls and potential future opportunities.
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Affiliation(s)
- Marit A de Beer
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - Ben N G Giepmans
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
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37
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The Riveting Cellular Structures of Apicomplexan Parasites. Trends Parasitol 2020; 36:979-991. [PMID: 33011071 DOI: 10.1016/j.pt.2020.09.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 08/31/2020] [Accepted: 09/03/2020] [Indexed: 12/21/2022]
Abstract
Parasitic protozoa of the phylum Apicomplexa cause a range of human and animal diseases. Their complex life cycles - often heteroxenous with sexual and asexual phases in different hosts - rely on elaborate cytoskeletal structures to enable morphogenesis and motility, organize cell division, and withstand diverse environmental forces. This review primarily focuses on studies using Toxoplasma gondii and Plasmodium spp. as the best studied apicomplexans; however, many cytoskeletal adaptations are broadly conserved and predate the emergence of the parasitic phylum. After decades cataloguing the constituents of such structures, a dynamic picture is emerging of the assembly and maintenance of apicomplexan cytoskeletons, illuminating how they template and orient critical processes during infection. These observations impact our view of eukaryotic diversity and offer future challenges for cell biology.
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38
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Young JC, Broncel M, Teague H, Russell MRG, McGovern OL, Renshaw M, Frith D, Snijders AP, Collinson L, Carruthers VB, Ewald SE, Treeck M. Phosphorylation of Toxoplasma gondii Secreted Proteins during Acute and Chronic Stages of Infection. mSphere 2020; 5:e00792-20. [PMID: 32907954 PMCID: PMC7485689 DOI: 10.1128/msphere.00792-20] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Accepted: 08/17/2020] [Indexed: 01/07/2023] Open
Abstract
The intracellular parasite Toxoplasma gondii resides within a membrane-bound parasitophorous vacuole (PV) and secretes an array of proteins to establish this replicative niche. It has been shown previously that Toxoplasma secretes kinases and that numerous proteins are phosphorylated after secretion. Here, we assess the role of the phosphorylation of strand-forming protein 1 (SFP1) and the related protein GRA29, two secreted proteins with unknown function. We show that both proteins form stranded structures in the PV that are independent of the previously described intravacuolar network or actin. SFP1 and GRA29 can each form these structures independently of other Toxoplasma secreted proteins, although GRA29 appears to regulate SFP1 strands. We show that an unstructured region at the C termini of SFP1 and GRA29 is required for the formation of strands and that mimicking the phosphorylation of this domain of SFP1 negatively regulates strand development. When tachyzoites convert to chronic-stage bradyzoites, both proteins show a dispersed localization throughout the cyst matrix. Many secreted proteins are reported to dynamically redistribute as the cyst forms, and secreted kinases are known to play a role in cyst formation. Using quantitative phosphoproteome and proteome analyses comparing tachyzoite and early bradyzoite stages, we reveal widespread differential phosphorylation of secreted proteins. While we found no direct evidence for phosphorylation playing a dominant role for SFP1/GRA29 redistribution in the cyst, these data support a model in which secreted kinases and phosphatases contribute to the regulation of secreted proteins during stage conversion.IMPORTANCEToxoplasma gondii is a common parasite that infects up to one-third of the human population. Initially, the parasite grows rapidly, infecting and destroying cells of the host, but subsequently switches to a slow-growing form and establishes chronic infection. In both stages, the parasite lives within a membrane-bound vacuole within the host cell, but in the chronic stage, a durable cyst wall is synthesized, which provides protection to the parasite during transmission to a new host. Toxoplasma secretes proteins into the vacuole to build its replicative niche, and previous studies identified many of these proteins as phosphorylated. We investigate two secreted proteins and show that a phosphorylated region plays an important role in their regulation in acute stages. We also observed widespread phosphorylation of secreted proteins when parasites convert from acute to chronic stages, providing new insight into how the cyst wall may be dynamically regulated.
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Affiliation(s)
- Joanna C Young
- Signalling in Apicomplexan Parasites Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Malgorzata Broncel
- Signalling in Apicomplexan Parasites Laboratory, The Francis Crick Institute, London, United Kingdom
- Proteomics Science Technology Platform, The Francis Crick Institute, London, United Kingdom
| | - Helena Teague
- Signalling in Apicomplexan Parasites Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Matt R G Russell
- Electron Microscopy Science Technology Platform, The Francis Crick Institute, London, United Kingdom
| | - Olivia L McGovern
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Matt Renshaw
- Advanced Light Microscopy Science Technology Platform, The Francis Crick Institute, London, United Kingdom
| | - David Frith
- Proteomics Science Technology Platform, The Francis Crick Institute, London, United Kingdom
| | - Ambrosius P Snijders
- Proteomics Science Technology Platform, The Francis Crick Institute, London, United Kingdom
| | - Lucy Collinson
- Electron Microscopy Science Technology Platform, The Francis Crick Institute, London, United Kingdom
| | - Vern B Carruthers
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Sarah E Ewald
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia, Charlottesville, Virginia, USA
- Carter Immunology Center, University of Virginia, Charlottesville, Virginia, USA
| | - Moritz Treeck
- Signalling in Apicomplexan Parasites Laboratory, The Francis Crick Institute, London, United Kingdom
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Zhang H, Liu J, Ying Z, Li S, Wu Y, Liu Q. Toxoplasma gondii UBL-UBA shuttle proteins contribute to the degradation of ubiquitinylated proteins and are important for synchronous cell division and virulence. FASEB J 2020; 34:13711-13725. [PMID: 32808330 DOI: 10.1096/fj.202000759rr] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 07/27/2020] [Accepted: 07/31/2020] [Indexed: 11/11/2022]
Abstract
Toxoplasma gondii is an obligate intracellular apicomplexan parasite that causes lethal diseases in immunocompromised patients. Ubiquitin-proteasome system (UPS) regulates many cellular processes by degrading ubiquitinylated proteins. The UBL-UBA shuttle protein family, which escorts the ubiquitinylated proteins to the proteasome for degradation, are crucial components of UPS. Here, we identified three UBL-UBA shuttle proteins (TGGT1_304680, DNA damage inducible protein 1, DDI1; TGGT1_295340, UV excision repair protein rad23 protein, RAD23; and TGGT1_223680, ubiquitin family protein, DSK2) localized in the cytoplasm and nucleus of T gondii. Deletion of shuttle proteins inhibited parasites growth and resulted in accumulation of ubiquitinylated proteins. Cell division of triple-gene knockout strain was asynchronous. In addition, we found that the retroviral aspartic protease activity of the nonclassical shuttle protein DDI1 was important for the virulence of Toxoplasma in mice. These results showed the critical roles of UBL-UBA shuttle proteins in regulating the degradation of ubiquitinylated proteins and cell division of T gondii.
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Affiliation(s)
- Heng Zhang
- National Animal Protozoa Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing, China.,Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Jing Liu
- National Animal Protozoa Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing, China.,Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Zhu Ying
- National Animal Protozoa Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing, China.,Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Shuang Li
- National Animal Protozoa Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing, China.,Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Yihan Wu
- National Animal Protozoa Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing, China.,Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Qun Liu
- National Animal Protozoa Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing, China.,Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, China
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40
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Dos Santos Pacheco N, Tosetti N, Koreny L, Waller RF, Soldati-Favre D. Evolution, Composition, Assembly, and Function of the Conoid in Apicomplexa. Trends Parasitol 2020; 36:688-704. [DOI: 10.1016/j.pt.2020.05.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 04/30/2020] [Accepted: 05/01/2020] [Indexed: 12/14/2022]
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41
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Bisio H, Soldati-Favre D. Signaling Cascades Governing Entry into and Exit from Host Cells by Toxoplasma gondii. Annu Rev Microbiol 2020; 73:579-599. [PMID: 31500539 DOI: 10.1146/annurev-micro-020518-120235] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The Apicomplexa phylum includes a large group of obligate intracellular protozoan parasites responsible for important diseases in humans and animals. Toxoplasma gondii is a widespread parasite with considerable versatility, and it is capable of infecting virtually any warm-blooded animal, including humans. This outstanding success can be attributed at least in part to an efficient and continuous sensing of the environment, with a ready-to-adapt strategy. This review updates the current understanding of the signals governing the lytic cycle of T. gondii, with particular focus on egress from infected cells, a key step for balancing survival, multiplication, and spreading in the host. We cover the recent advances in the conceptual framework of regulation of microneme exocytosis that ensures egress, motility, and invasion. Particular emphasis is given to the trigger molecules and signaling cascades regulating exit from host cells.
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Affiliation(s)
- Hugo Bisio
- Département de Microbiologie et Médecine Moléculaire, Centre Médical Universitaire, Université de Genève, 1211 Geneva 4, Switzerland;
| | - Dominique Soldati-Favre
- Département de Microbiologie et Médecine Moléculaire, Centre Médical Universitaire, Université de Genève, 1211 Geneva 4, Switzerland;
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42
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Pavlou G, Touquet B, Vigetti L, Renesto P, Bougdour A, Debarre D, Balland M, Tardieux I. Coupling Polar Adhesion with Traction, Spring, and Torque Forces Allows High-Speed Helical Migration of the Protozoan Parasite Toxoplasma. ACS NANO 2020; 14:7121-7139. [PMID: 32432851 DOI: 10.1021/acsnano.0c01893] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Among the eukaryotic cells that navigate through fully developed metazoan tissues, protozoans from the Apicomplexa phylum have evolved motile developmental stages that move much faster than the fastest crawling cells owing to a peculiar substrate-dependent type of motility, known as gliding. Best-studied models are the Plasmodium sporozoite and the Toxoplasma tachyzoite polarized cells for which motility is vital to achieve their developmental programs in the metazoan hosts. The gliding machinery is shared between the two parasites and is largely characterized. Localized beneath the cell surface, it includes actin filaments, unconventional myosin motors housed within a multimember glideosome unit, and apically secreted transmembrane adhesins. In contrast, less is known about the force mechanisms powering cell movement. Pioneered biophysical studies on the sporozoite and phenotypic analysis of tachyzoite actin-related mutants have added complexity to the general view that force production for parasite forward movement directly results from the myosin-driven rearward motion of the actin-coupled adhesion sites. Here, we have interrogated how forces and substrate adhesion-de-adhesion cycles operate and coordinate to allow the typical left-handed helical gliding mode of the tachyzoite. By combining quantitative traction force and reflection interference microscopy with micropatterning and expansion microscopy, we unveil at the millisecond and nanometer scales the integration of a critical apical anchoring adhesion with specific traction and spring-like forces. We propose that the acto-myoA motor directs the traction force which allows transient energy storage by the microtubule cytoskeleton and therefore sets the thrust force required for T. gondii tachyzoite vital helical gliding capacity.
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Affiliation(s)
- Georgios Pavlou
- Institute for Advanced Biosciences (IAB), Team Membrane Dynamics of Parasite-Host Cell Interactions, CNRS UMR5309, INSERM U1209, Université Grenoble Alpes, 38700 Grenoble, France
| | - Bastien Touquet
- Institute for Advanced Biosciences (IAB), Team Membrane Dynamics of Parasite-Host Cell Interactions, CNRS UMR5309, INSERM U1209, Université Grenoble Alpes, 38700 Grenoble, France
| | - Luis Vigetti
- Institute for Advanced Biosciences (IAB), Team Membrane Dynamics of Parasite-Host Cell Interactions, CNRS UMR5309, INSERM U1209, Université Grenoble Alpes, 38700 Grenoble, France
| | - Patricia Renesto
- Institute for Advanced Biosciences (IAB), Team Membrane Dynamics of Parasite-Host Cell Interactions, CNRS UMR5309, INSERM U1209, Université Grenoble Alpes, 38700 Grenoble, France
- TIMC-IMAG UMR 5525 - UGA CNRS, 38700 Grenoble, France
| | - Alexandre Bougdour
- Institute for Advanced Biosciences (IAB), Team Host-Pathogen Interactions & Immunity to Infections, CNRS UMR5309, INSERM U1209, Université Grenoble Alpes, 38700 Grenoble, France
| | - Delphine Debarre
- Laboratoire Interdisciplinaire de Physique, UMR CNRS, 5588, Université Grenoble Alpes, Grenoble 38402, France
| | - Martial Balland
- Laboratoire Interdisciplinaire de Physique, UMR CNRS, 5588, Université Grenoble Alpes, Grenoble 38402, France
| | - Isabelle Tardieux
- Institute for Advanced Biosciences (IAB), Team Membrane Dynamics of Parasite-Host Cell Interactions, CNRS UMR5309, INSERM U1209, Université Grenoble Alpes, 38700 Grenoble, France
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Gubbels MJ, Keroack CD, Dangoudoubiyam S, Worliczek HL, Paul AS, Bauwens C, Elsworth B, Engelberg K, Howe DK, Coppens I, Duraisingh MT. Fussing About Fission: Defining Variety Among Mainstream and Exotic Apicomplexan Cell Division Modes. Front Cell Infect Microbiol 2020; 10:269. [PMID: 32582569 PMCID: PMC7289922 DOI: 10.3389/fcimb.2020.00269] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2020] [Accepted: 05/06/2020] [Indexed: 12/17/2022] Open
Abstract
Cellular reproduction defines life, yet our textbook-level understanding of cell division is limited to a small number of model organisms centered around humans. The horizon on cell division variants is expanded here by advancing insights on the fascinating cell division modes found in the Apicomplexa, a key group of protozoan parasites. The Apicomplexa display remarkable variation in offspring number, whether karyokinesis follows each S/M-phase or not, and whether daughter cells bud in the cytoplasm or bud from the cortex. We find that the terminology used to describe the various manifestations of asexual apicomplexan cell division emphasizes either the number of offspring or site of budding, which are not directly comparable features and has led to confusion in the literature. Division modes have been primarily studied in two human pathogenic Apicomplexa, malaria-causing Plasmodium spp. and Toxoplasma gondii, a major cause of opportunistic infections. Plasmodium spp. divide asexually by schizogony, producing multiple daughters per division round through a cortical budding process, though at several life-cycle nuclear amplifications stages, are not followed by karyokinesis. T. gondii divides by endodyogeny producing two internally budding daughters per division round. Here we add to this diversity in replication mechanisms by considering the cattle parasite Babesia bigemina and the pig parasite Cystoisospora suis. B. bigemina produces two daughters per division round by a “binary fission” mechanism whereas C. suis produces daughters through both endodyogeny and multiple internal budding known as endopolygeny. In addition, we provide new data from the causative agent of equine protozoal myeloencephalitis (EPM), Sarcocystis neurona, which also undergoes endopolygeny but differs from C. suis by maintaining a single multiploid nucleus. Overall, we operationally define two principally different division modes: internal budding found in cyst-forming Coccidia (comprising endodyogeny and two forms of endopolygeny) and external budding found in the other parasites studied (comprising the two forms of schizogony, binary fission and multiple fission). Progressive insights into the principles defining the molecular and cellular requirements for internal vs. external budding, as well as variations encountered in sexual stages are discussed. The evolutionary pressures and mechanisms underlying apicomplexan cell division diversification carries relevance across Eukaryota.
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Affiliation(s)
- Marc-Jan Gubbels
- Department of Biology, Boston College, Chestnut Hill, MA, United States
| | - Caroline D Keroack
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Harvard University, Boston, MA, United States
| | - Sriveny Dangoudoubiyam
- Department of Veterinary Science, Gluck Equine Research Center, University of Kentucky, Lexington, KY, United States
| | - Hanna L Worliczek
- Department of Biology, Boston College, Chestnut Hill, MA, United States.,Institute of Parasitology, University of Veterinary Medicine, Vienna, Austria
| | - Aditya S Paul
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Harvard University, Boston, MA, United States
| | - Ciara Bauwens
- Department of Biology, Boston College, Chestnut Hill, MA, United States
| | - Brendan Elsworth
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Harvard University, Boston, MA, United States.,School of Biosciences, University of Melbourne, Melbourne, VIC, Australia
| | - Klemens Engelberg
- Department of Biology, Boston College, Chestnut Hill, MA, United States
| | - Daniel K Howe
- Department of Veterinary Science, Gluck Equine Research Center, University of Kentucky, Lexington, KY, United States
| | - Isabelle Coppens
- Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, United States
| | - Manoj T Duraisingh
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Harvard University, Boston, MA, United States
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Venugopal K, Chehade S, Werkmeister E, Barois N, Periz J, Lafont F, Tardieux I, Khalife J, Langsley G, Meissner M, Marion S. Rab11A regulates dense granule transport and secretion during Toxoplasma gondii invasion of host cells and parasite replication. PLoS Pathog 2020; 16:e1008106. [PMID: 32463830 PMCID: PMC7255593 DOI: 10.1371/journal.ppat.1008106] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Accepted: 02/10/2020] [Indexed: 12/31/2022] Open
Abstract
Toxoplasma gondii possesses an armada of secreted virulent factors that enable parasite invasion and survival into host cells. These factors are contained in specific secretory organelles, the rhoptries, micronemes and dense granules that release their content upon host cell recognition. Dense granules are secreted in a constitutive manner during parasite replication and play a crucial role in modulating host metabolic and immune responses. While the molecular mechanisms triggering rhoptry and microneme release upon host cell adhesion have been well studied, constitutive secretion remains a poorly explored aspect of T. gondii vesicular trafficking. Here, we investigated the role of the small GTPase Rab11A, a known regulator of exocytosis in eukaryotic cells. Our data revealed an essential role of Rab11A in promoting the cytoskeleton driven transport of dense granules and the release of their content into the vacuolar space. Rab11A also regulates transmembrane protein trafficking and localization during parasite replication, indicating a broader role of Rab11A in cargo exocytosis at the plasma membrane. Moreover, we found that Rab11A also regulates extracellular parasite motility and adhesion to host cells. In line with these findings, MIC2 secretion was altered in Rab11A-defective parasites, which also exhibited severe morphological defects. Strikingly, by live imaging we observed a polarized accumulation of Rab11A-positive vesicles and dense granules at the apical pole of extracellular motile and invading parasites suggesting that apically polarized Rab11A-dependent delivery of cargo regulates early secretory events during parasite entry into host cells. Toxoplasma gondii (T. gondii) is a highly prevalent parasite infecting a wide range of animals as well as humans. T. gondii secretes numerous virulent factors contained in specific organelles, termed the rhoptries, micronemes and dense granules. These factors are released upon host cell recognition and enable parasite invasion and subsequent development into an intracellular vacuole. In particular, dense granules contain critical effectors that modulate intrinsic defenses of infected host cells ensuring parasite survival and dissemination. The mechanisms regulating dense granule secretion have not been elucidated. In this study, we unraveled a novel role for the T. gondii GTPase Rab11A in promoting dense granule transport along the parasite cytoskeleton and their content release into the vacuolar space during parasite replication. We also found that T. gondii Rab11A regulates extracellular parasite motility and adhesion to host cells suggesting a broader role in distinct secretory pathways essential for parasite virulence.
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Affiliation(s)
- Kannan Venugopal
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019—UMR 9017—CIIL—Center for Infection and Immunity of Lille, Lille, France
| | - Sylia Chehade
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019—UMR 9017—CIIL—Center for Infection and Immunity of Lille, Lille, France
| | - Elisabeth Werkmeister
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019—UMR 9017—CIIL—Center for Infection and Immunity of Lille, Lille, France
| | - Nicolas Barois
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019—UMR 9017—CIIL—Center for Infection and Immunity of Lille, Lille, France
| | - Javier Periz
- Department of Veterinary Sciences, Experimental Parasitology, Ludwig-Maximilians-Universität, Munich, Germany
| | - Frank Lafont
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019—UMR 9017—CIIL—Center for Infection and Immunity of Lille, Lille, France
| | - Isabelle Tardieux
- Institute for Advanced Biosciences (IAB), Membrane Dynamics of Parasite-Host Cell Interactions, CNRS UMR5309, INSERM U1209, Université Grenoble Alpes, Grenoble, France
| | - Jamal Khalife
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019—UMR 9017—CIIL—Center for Infection and Immunity of Lille, Lille, France
| | - Gordon Langsley
- Laboratoire de Biologie Comparative des Apicomplexes, Faculté de Médicine, Université Paris Descartes—Sorbonne Paris Cité, France, INSERM U1016, CNRS UMR8104, Institut Cochin, Paris, France
| | - Markus Meissner
- Department of Veterinary Sciences, Experimental Parasitology, Ludwig-Maximilians-Universität, Munich, Germany
| | - Sabrina Marion
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019—UMR 9017—CIIL—Center for Infection and Immunity of Lille, Lille, France
- * E-mail:
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45
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O’Shaughnessy WJ, Hu X, Beraki T, McDougal M, Reese ML. Loss of a conserved MAPK causes catastrophic failure in assembly of a specialized cilium-like structure in Toxoplasma gondii. Mol Biol Cell 2020; 31:881-888. [PMID: 32073987 PMCID: PMC7185968 DOI: 10.1091/mbc.e19-11-0607] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Revised: 02/03/2020] [Accepted: 02/14/2020] [Indexed: 12/26/2022] Open
Abstract
Primary cilia are important organizing centers that control diverse cellular processes. Apicomplexan parasites like Toxoplasma gondii have a specialized cilium-like structure called the conoid that organizes the secretory and invasion machinery critical for the parasites' lifestyle. The proteins that initiate the biogenesis of this structure are largely unknown. We identified the Toxoplasma orthologue of the conserved kinase ERK7 as essential to conoid assembly. Parasites in which ERK7 has been depleted lose their conoids late during maturation and are immotile and thus unable to invade new host cells. This is the most severe phenotype to conoid biogenesis yet reported, and is made more striking by the fact that ERK7 is not a conoid protein, as it localizes just basal to the structure. ERK7 has been recently implicated in ciliogenesis in metazoan cells, and our data suggest that this kinase has an ancient and central role in regulating ciliogenesis throughout Eukaryota.
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Affiliation(s)
| | - Xiaoyu Hu
- Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX 75390
| | - Tsebaot Beraki
- Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX 75390
| | - Matthew McDougal
- Department of Microbiology, UT Southwestern Medical Center, Dallas, TX 75390
| | - Michael L. Reese
- Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX 75390
- Department of Biochemistry, UT Southwestern Medical Center, Dallas, TX 75390
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46
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Trivedi DV, Nag S, Spudich A, Ruppel KM, Spudich JA. The Myosin Family of Mechanoenzymes: From Mechanisms to Therapeutic Approaches. Annu Rev Biochem 2020; 89:667-693. [PMID: 32169021 DOI: 10.1146/annurev-biochem-011520-105234] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Myosins are among the most fascinating enzymes in biology. As extremely allosteric chemomechanical molecular machines, myosins are involved in myriad pivotal cellular functions and are frequently sites of mutations leading to disease phenotypes. Human β-cardiac myosin has proved to be an excellent target for small-molecule therapeutics for heart muscle diseases, and, as we describe here, other myosin family members are likely to be potentially unique targets for treating other diseases as well. The first part of this review focuses on how myosins convert the chemical energy of ATP hydrolysis into mechanical movement, followed by a description of existing therapeutic approaches to target human β-cardiac myosin. The next section focuses on the possibility of targeting nonmuscle members of the human myosin family for several diseases. We end the review by describing the roles of myosin in parasites and the therapeutic potential of targeting them to block parasitic invasion of their hosts.
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Affiliation(s)
- Darshan V Trivedi
- Department of Biochemistry, Stanford University School of Medicine, Stanford, California 94305, USA; , , .,Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, California 94305, USA
| | - Suman Nag
- MyoKardia Inc., Brisbane, California 94005, USA;
| | - Annamma Spudich
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bangalore 560-097, India;
| | - Kathleen M Ruppel
- Department of Biochemistry, Stanford University School of Medicine, Stanford, California 94305, USA; , , .,Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, California 94305, USA.,Division of Pediatric Cardiology, Department of Pediatrics, Stanford University School of Medicine, Stanford, California 94305, USA
| | - James A Spudich
- Department of Biochemistry, Stanford University School of Medicine, Stanford, California 94305, USA; , , .,Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, California 94305, USA
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Frénal K, Krishnan A, Soldati-Favre D. The Actomyosin Systems in Apicomplexa. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1239:331-354. [PMID: 32451865 DOI: 10.1007/978-3-030-38062-5_14] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The phylum of Apicomplexa groups obligate intracellular parasites that exhibit unique classes of unconventional myosin motors. These parasites also encode a limited repertoire of actins, actin-like proteins, actin-binding proteins and nucleators of filamentous actin (F-actin) that display atypical properties. In the last decade, significant progress has been made to visualize F-actin and to unravel the functional contribution of actomyosin systems in the biology of Toxoplasma and Plasmodium, the most genetically-tractable members of the phylum. In addition to assigning specific roles to each myosin, recent biochemical and structural studies have begun to uncover mechanistic insights into myosin function at the atomic level. In several instances, the myosin light chains associated with the myosin heavy chains have been identified, helping to understand the composition of the motor complexes and their mode of regulation. Moreover, the considerable advance in proteomic methodologies and especially in assignment of posttranslational modifications is offering a new dimension to our understanding of the regulation of actin dynamics and myosin function. Remarkably, the actomyosin system contributes to three major processes in Toxoplasma gondii: (i) organelle trafficking, positioning and inheritance, (ii) basal pole constriction and intravacuolar cell-cell communication and (iii) motility, invasion, and egress from infected cells. In this chapter, we summarize how the actomyosin system harnesses these key events to ensure successful completion of the parasite life cycle.
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Affiliation(s)
- Karine Frénal
- Microbiologie Fondamentale et Pathogénicité, UMR 5234, University of Bordeaux and CNRS, Bordeaux Cedex, France. .,Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland.
| | - Aarti Krishnan
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Dominique Soldati-Favre
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
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Del Rosario M, Periz J, Pavlou G, Lyth O, Latorre‐Barragan F, Das S, Pall GS, Stortz JF, Lemgruber L, Whitelaw JA, Baum J, Tardieux I, Meissner M. Apicomplexan F-actin is required for efficient nuclear entry during host cell invasion. EMBO Rep 2019; 20:e48896. [PMID: 31584242 PMCID: PMC6893294 DOI: 10.15252/embr.201948896] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2019] [Revised: 08/21/2019] [Accepted: 09/11/2019] [Indexed: 12/16/2022] Open
Abstract
The obligate intracellular parasites Toxoplasma gondii and Plasmodium spp. invade host cells by injecting a protein complex into the membrane of the targeted cell that bridges the two cells through the assembly of a ring-like junction. This circular junction stretches while the parasites apply a traction force to pass through, a step that typically concurs with transient constriction of the parasite body. Here we analyse F-actin dynamics during host cell invasion. Super-resolution microscopy and real-time imaging highlighted an F-actin pool at the apex of pre-invading parasite, an F-actin ring at the junction area during invasion but also networks of perinuclear and posteriorly localised F-actin. Mutant parasites with dysfunctional acto-myosin showed significant decrease of junctional and perinuclear F-actin and are coincidently affected in nuclear passage through the junction. We propose that the F-actin machinery eases nuclear passage by stabilising the junction and pushing the nucleus through the constriction. Our analysis suggests that the junction opposes resistance to the passage of the parasite's nucleus and provides the first evidence for a dual contribution of actin-forces during host cell invasion by apicomplexan parasites.
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Affiliation(s)
- Mario Del Rosario
- Wellcome Centre For Integrative ParasitologyInstitute of InfectionImmunity & Inflammation, Glasgow Biomedical Research CentreUniversity of GlasgowGlasgowUK
| | - Javier Periz
- Wellcome Centre For Integrative ParasitologyInstitute of InfectionImmunity & Inflammation, Glasgow Biomedical Research CentreUniversity of GlasgowGlasgowUK
| | - Georgios Pavlou
- Institute for Advanced BiosciencesCNRS, UMR5309, INSERM U1209Université Grenoble AlpesGrenobleFrance
| | - Oliver Lyth
- Department of Life SciencesImperial College LondonLondonUK
| | - Fernanda Latorre‐Barragan
- Wellcome Centre For Integrative ParasitologyInstitute of InfectionImmunity & Inflammation, Glasgow Biomedical Research CentreUniversity of GlasgowGlasgowUK
- Faculty of Science, Food Engineering and BiotechnologyTechnical University of AmbatoAmbatoEcuador
| | - Sujaan Das
- Wellcome Centre For Integrative ParasitologyInstitute of InfectionImmunity & Inflammation, Glasgow Biomedical Research CentreUniversity of GlasgowGlasgowUK
| | - Gurman S Pall
- Wellcome Centre For Integrative ParasitologyInstitute of InfectionImmunity & Inflammation, Glasgow Biomedical Research CentreUniversity of GlasgowGlasgowUK
| | - Johannes Felix Stortz
- Wellcome Centre For Integrative ParasitologyInstitute of InfectionImmunity & Inflammation, Glasgow Biomedical Research CentreUniversity of GlasgowGlasgowUK
| | - Leandro Lemgruber
- Wellcome Centre For Integrative ParasitologyInstitute of InfectionImmunity & Inflammation, Glasgow Biomedical Research CentreUniversity of GlasgowGlasgowUK
| | | | - Jake Baum
- Department of Life SciencesImperial College LondonLondonUK
| | - Isabelle Tardieux
- Institute for Advanced BiosciencesCNRS, UMR5309, INSERM U1209Université Grenoble AlpesGrenobleFrance
| | - Markus Meissner
- Wellcome Centre For Integrative ParasitologyInstitute of InfectionImmunity & Inflammation, Glasgow Biomedical Research CentreUniversity of GlasgowGlasgowUK
- Experimental ParasitologyDepartment for Veterinary SciencesLudwig‐Maximilians‐University Munich MunichGermany
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49
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Guevara RB, Fox BA, Falla A, Bzik DJ. Toxoplasma gondii Intravacuolar-Network-Associated Dense Granule Proteins Regulate Maturation of the Cyst Matrix and Cyst Wall. mSphere 2019; 4:e00487-19. [PMID: 31619500 PMCID: PMC6796980 DOI: 10.1128/msphere.00487-19] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Accepted: 09/30/2019] [Indexed: 11/21/2022] Open
Abstract
Little is known regarding how the chronic Toxoplasma gondii cyst develops. Here, we investigated intravacuolar-network-associated dense granule (GRA) proteins GRA1, GRA2, GRA4, GRA6, GRA9, and GRA12 during cyst development in vitro after differentiation of the tachyzoite-stage parasitophorous vacuole. By day 1 postdifferentiation, GRA1, GRA4, GRA6, GRA9, and GRA12 colocalized with Dolichos biflorus agglutinin stain at the cyst periphery. In contrast, GRA2 remained in the cyst matrix. By day 2 postdifferentiation, coinciding with localization of GRA2 to the cyst periphery, GRA1, GRA4, GRA6, and GRA9 established a continuous matrix pattern in the cyst. In contrast, GRA2 and GRA12 were colocalized in prominent cyst matrix puncta throughout cyst development. While GRA2, GRA6, and GRA12 localized in outer and inner layers of the cyst wall, GRA1, GRA4, and GRA9 localized predominantly in the inner layers of the cyst wall. GRA2 and GRA12 were colocalized in the cyst wall by day 7 postdifferentiation. However, by day 10 postdifferentiation, GRA12 was relocalized from the cyst wall to puncta in the cyst matrix. Differentiation of Δgra2 parasites revealed a defect in the ability to establish a normal cyst matrix. In addition, the deletion of any intravacuolar-network-associated GRA protein, except GRA1, reduced the rate of accumulation of cyst wall proteins at the cyst periphery relative to the cyst interior. Our findings reveal dynamic patterns of GRA protein localization during cyst development and suggest that intravacuolar-network-associated GRA proteins regulate the formation and maturation of the cyst matrix and cyst wall structures.IMPORTANCEToxoplasma gondii establishes chronic infection in humans by forming thick-walled cysts that persist in the brain. If host immunity wanes, cysts reactivate to cause severe, and often lethal, toxoplasmic encephalitis. There is no available therapy to eliminate cysts or to prevent their reactivation. Moreover, how the vital and characteristic cyst matrix and cyst wall structures develop is poorly understood. Here, we visualized and tracked the localization of Toxoplasma intravacuolar-network-associated dense granule (GRA) proteins during cyst development in vitro Intravacuolar-network GRAs were present within the cyst matrix and at the cyst wall in developing cysts, and genetic deletion of intravacuolar-network-associated GRAs reduced the rate of accumulation of cyst wall material at the cyst periphery. Our results show that intravacuolar-network-associated GRAs, particularly GRA2 and GRA12, play dynamic and essential roles in the development and maturation of the cyst matrix and the cyst wall structures.
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Affiliation(s)
- Rebekah B Guevara
- Department of Microbiology and Immunology, The Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire, USA
| | - Barbara A Fox
- Department of Microbiology and Immunology, The Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire, USA
| | - Alejandra Falla
- Department of Microbiology and Immunology, The Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire, USA
| | - David J Bzik
- Department of Microbiology and Immunology, The Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire, USA
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50
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Craig EW, Mueller DM, Bigge BM, Schaffer M, Engel BD, Avasthi P. The elusive actin cytoskeleton of a green alga expressing both conventional and divergent actins. Mol Biol Cell 2019; 30:2827-2837. [PMID: 31532705 PMCID: PMC6789165 DOI: 10.1091/mbc.e19-03-0141] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 09/06/2019] [Accepted: 09/10/2019] [Indexed: 12/13/2022] Open
Abstract
The green alga Chlamydomonas reinhardtii is a leading model system to study photosynthesis, cilia, and the generation of biological products. The cytoskeleton plays important roles in all of these cellular processes, but to date, the filamentous actin network within Chlamydomonas has remained elusive. By optimizing labeling conditions, we can now visualize distinct linear actin filaments at the posterior of the nucleus in both live and fixed vegetative cells. Using in situ cryo-electron tomography, we confirmed this localization by directly imaging actin filaments within the native cellular environment. The fluorescently labeled structures are sensitive to the depolymerizing agent latrunculin B (Lat B), demonstrating the specificity of our optimized labeling method. Interestingly, Lat B treatment resulted in the formation of a transient ring-like filamentous actin structure around the nucleus. The assembly of this perinuclear ring is dependent upon a second actin isoform, NAP1, which is strongly up-regulated upon Lat B treatment and is insensitive to Lat B-induced depolymerization. Our study combines orthogonal strategies to provide the first detailed visual characterization of filamentous actins in Chlamydomonas, allowing insights into the coordinated functions of two actin isoforms expressed within the same cell.
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Affiliation(s)
- Evan W. Craig
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, KS 66160
| | - David M. Mueller
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, KS 66160
| | - Brae M. Bigge
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, KS 66160
| | - Miroslava Schaffer
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Benjamin D. Engel
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Prachee Avasthi
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, KS 66160
- Department of Ophthalmology, University of Kansas Medical Center, Kansas City, KS 66160
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