1
|
Basant A, Way M. The amount of Nck rather than N-WASP correlates with the rate of actin-based motility of Vaccinia virus. Microbiol Spectr 2023; 11:e0152923. [PMID: 37855608 PMCID: PMC10883800 DOI: 10.1128/spectrum.01529-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Accepted: 09/03/2023] [Indexed: 10/20/2023] Open
Abstract
IMPORTANCE Vaccinia virus is a large double-stranded DNA virus and a close relative of Mpox and Variola virus, the causative agent of smallpox. During infection, Vaccinia hijacks its host's transport systems and promotes its spread into neighboring cells by recruiting a signaling network that stimulates actin polymerization. Over the years, Vaccinia has provided a powerful model to understand how signaling networks regulate actin polymerization. Nevertheless, we still lack important quantitative information about the system, including the precise number of viral and host molecules required to induce actin polymerization. Using quantitative fluorescence microscopy techniques, we have determined the number of viral and host signaling proteins accumulating on virions during their egress. Our analysis has uncovered two unexpected new aspects of this process: the number of viral proteins in the virion is not fixed and the velocity of virus movement depends on the level of a single adaptor within the signaling network.
Collapse
Affiliation(s)
- Angika Basant
- Cellular Signalling and Cytoskeletal Function Laboratory, The Francis Crick Institute , London, United Kingdom
| | - Michael Way
- Cellular Signalling and Cytoskeletal Function Laboratory, The Francis Crick Institute , London, United Kingdom
- Department of Infectious Disease, Imperial College , London, United Kingdom
| |
Collapse
|
2
|
Lee M, Joo S, Lee TG. Quantitative evaluation of brightness of fluorescent nanoparticles using
DNA
origami standards. B KOREAN CHEM SOC 2023. [DOI: 10.1002/bkcs.12691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2023]
Affiliation(s)
- Mina Lee
- Safety Measurement Institute Korea Research Institute of Standards and Science (KRISS) Daejeon South Korea
| | - Sihwa Joo
- Safety Measurement Institute Korea Research Institute of Standards and Science (KRISS) Daejeon South Korea
| | - Tae Geol Lee
- Safety Measurement Institute Korea Research Institute of Standards and Science (KRISS) Daejeon South Korea
- Department of Nano Science University of Science and Technology (UST) Daejeon South Korea
| |
Collapse
|
3
|
Leung JM, Nagayasu E, Hwang YC, Liu J, Pierce PG, Phan IQ, Prentice RA, Murray JM, Hu K. A doublecortin-domain protein of Toxoplasma and its orthologues bind to and modify the structure and organization of tubulin polymers. BMC Mol Cell Biol 2020; 21:8. [PMID: 32111164 PMCID: PMC7048138 DOI: 10.1186/s12860-020-0249-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 01/31/2020] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND TgDCX is a doublecortin-domain protein associated with the conoid fibers, a set of strongly curved non-tubular tubulin-polymers in Toxoplasma. TgDCX deletion impairs conoid structure and parasite invasion. TgDCX contains two tubulin-binding domains: a partial P25α and the DCX/doublecortin domain. Orthologues are found in apicomplexans and their free-living relatives Chromera and Vitrella. RESULTS We report that isolated TgDCX-containing conoid fibers retain their pronounced curvature, but loss of TgDCX destabilizes the fibers. We crystallized and determined the 3D-structure of the DCX-domain, which is similar to those of human doublecortin and well-conserved among TgDCX orthologues. However, the orthologues vary widely in targeting to the conoid in Toxoplasma and in modulating microtubule organization in Xenopus cells. Several orthologues bind to microtubules in Xenopus cells, but only TgDCX generates short, strongly curved microtubule arcs. EM analysis shows microtubules decorated with TgDCX bundled into rafts, often bordered on one edge by a "C"-shaped incomplete tube. A Chromera orthologue closely mimics TgDCX targeting in Toxoplasma and binds to microtubules in Xenopus cells, but does not generate arcs or "C"-shaped tubes, and fails to rescue the defects of the TgDCX-knockout parasite. CONCLUSIONS These observations suggest that species-specific features of TgDCX enable it to generate strongly curved tubulin-polymers to support efficient host-cell invasion.
Collapse
Affiliation(s)
| | - Eiji Nagayasu
- Department of Infectious Diseases, Division of Parasitology, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan
| | - Yu-Chen Hwang
- Nikon Instruments Inc, Melville, New York, 11747, USA
| | - Jun Liu
- Department of Biology, Indiana University, Bloomington, IN, 47405, USA
| | - Phillip G Pierce
- UCB, and Seattle Structural Genomics Center for Infectious Disease, Bainbridge Island, WA, 98110, USA
| | - Isabelle Q Phan
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, and Seattle Structural Genomics Center for Infectious Disease, Seattle, WA, 98109, USA
| | - Robin A Prentice
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, and Seattle Structural Genomics Center for Infectious Disease, Seattle, WA, 98109, USA
- University of Washington, Brotman Bady Institute, Seattle, WA, 98195, USA
| | - John M Murray
- Department of Biology, Indiana University, Bloomington, IN, 47405, USA
| | - Ke Hu
- Department of Biology, Indiana University, Bloomington, IN, 47405, USA.
| |
Collapse
|
4
|
Leung JM, Liu J, Wetzel LA, Hu K. Centrin2 from the human parasite Toxoplasma gondii is required for its invasion and intracellular replication. J Cell Sci 2019; 132:jcs.228791. [PMID: 31182647 DOI: 10.1242/jcs.228791] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 06/03/2019] [Indexed: 12/24/2022] Open
Abstract
Centrins are EF-hand containing proteins ubiquitously found in eukaryotes and are key components of centrioles/basal bodies as well as certain contractile fibers. We previously identified three centrins in the human parasite Toxoplasma gondii, all of which localized to the centrioles. However, one of them, T. gondii (Tg) Centrin2 (CEN2), is also targeted to structures at the apical and basal ends of the parasite, as well as to annuli at the base of the apical cap of the membrane cortex. The role(s) that CEN2 play in these locations were unknown. Here, we report the functional characterization of CEN2 using a conditional knockdown method that combines transcriptional and protein stability control. The knockdown resulted in an ordered loss of CEN2 from its four compartments, due to differences in incorporation kinetics and structural inheritance over successive generations. This was correlated with a major invasion deficiency at early stages of CEN2 knockdown, and replication defects at later stages. These results indicate that CEN2 is incorporated into multiple cytoskeletal structures to serve distinct functions that are required for parasite survival.
Collapse
Affiliation(s)
| | - Jun Liu
- Department of Biology, Indiana University, Bloomington, IN 47405, USA
| | - Laura A Wetzel
- Department of Biology, Indiana University, Bloomington, IN 47405, USA
| | - Ke Hu
- Department of Biology, Indiana University, Bloomington, IN 47405, USA
| |
Collapse
|
5
|
Harding CR, Gow M, Kang JH, Shortt E, Manalis SR, Meissner M, Lourido S. Alveolar proteins stabilize cortical microtubules in Toxoplasma gondii. Nat Commun 2019; 10:401. [PMID: 30674885 PMCID: PMC6344517 DOI: 10.1038/s41467-019-08318-7] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 01/04/2019] [Indexed: 12/21/2022] Open
Abstract
Single-celled protists use elaborate cytoskeletal structures, including arrays of microtubules at the cell periphery, to maintain polarity and rigidity. The obligate intracellular parasite Toxoplasma gondii has unusually stable cortical microtubules beneath the alveoli, a network of flattened membrane vesicles that subtends the plasmalemma. However, anchoring of microtubules along alveolar membranes is not understood. Here, we show that GAPM1a, an integral membrane protein of the alveoli, plays a role in maintaining microtubule stability. Degradation of GAPM1a causes cortical microtubule disorganisation and subsequent depolymerisation. These changes in the cytoskeleton lead to parasites becoming shorter and rounder, which is accompanied by a decrease in cellular volume. Extended GAPM1a depletion leads to severe defects in division, reminiscent of the effect of disrupting other alveolar proteins. We suggest that GAPM proteins link the cortical microtubules to the alveoli and are required to maintain the shape and rigidity of apicomplexan zoites. Cortical microtubules of Toxoplasma gondii are exceptionally stable, but it isn’t known how they are anchored along membranes. Here, Harding et al. show that GAPM proteins localize to the inner membrane complex and are essential for maintaining the structural stability of parasites.
Collapse
Affiliation(s)
- Clare R Harding
- Whitehead Institute for Biomedical Research, Cambridge, 02142, MA, USA.
| | - Matthew Gow
- Wellcome Centre for Molecular Parasitology, Institute of Infection, Immunity & Inflammation, University of Glasgow, Glasgow, G12 8TA, UK
| | - Joon Ho Kang
- Department of Physics, Massachusetts Institute of Technology, Cambridge, 02139, MA, USA.,Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, 02139, MA, USA
| | - Emily Shortt
- Whitehead Institute for Biomedical Research, Cambridge, 02142, MA, USA
| | - Scott R Manalis
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, 02139, MA, USA.,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, 02139, MA, USA.,Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, 02139, MA, USA
| | - Markus Meissner
- Wellcome Centre for Molecular Parasitology, Institute of Infection, Immunity & Inflammation, University of Glasgow, Glasgow, G12 8TA, UK.,Department of Veterinary Sciences, Ludwig-Maximilians-Universität, Munich, 80539, Germany
| | - Sebastian Lourido
- Whitehead Institute for Biomedical Research, Cambridge, 02142, MA, USA. .,Biology Department, Massachusetts Institute of Technology, Cambridge, 02139, MA, USA.
| |
Collapse
|