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Ahmad T, Alhammadi BA, Almaazmi SY, Arafa S, Blatch GL, Dutta T, Gestwicki JE, Keyzers RA, Shonhai A, Singh H. Plasmodium falciparum heat shock proteins as antimalarial drug targets: An update. Cell Stress Chaperones 2024; 29:326-337. [PMID: 38518861 PMCID: PMC10990865 DOI: 10.1016/j.cstres.2024.03.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Revised: 02/25/2024] [Accepted: 03/18/2024] [Indexed: 03/24/2024] Open
Abstract
Global efforts to eradicate malaria are threatened by multiple factors, particularly the emergence of antimalarial drug resistant strains of Plasmodium falciparum. Heat shock proteins (HSPs), particularly P. falciparum HSPs (PfHSPs), represent promising drug targets due to their essential roles in parasite survival and virulence across the various life cycle stages. Despite structural similarities between human and malarial HSPs posing challenges, there is substantial evidence for subtle differences that could be exploited for selective drug targeting. This review provides an update on the potential of targeting various PfHSP families (particularly PfHSP40, PfHSP70, and PfHSP90) and their interactions within PfHSP complexes as a strategy to develop new antimalarial drugs. In addition, the need for a deeper understanding of the role of HSP complexes at the host-parasite interface is highlighted, especially heterologous partnerships between human and malarial HSPs, as this opens novel opportunities for targeting protein-protein interactions crucial for malaria parasite survival and pathogenesis.
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Affiliation(s)
- Tanveer Ahmad
- Faculty of Health Sciences, Higher Colleges of Technology, Sharjah, United Arab Emirates
| | - Bushra A Alhammadi
- Faculty of Health Sciences, Higher Colleges of Technology, Sharjah, United Arab Emirates
| | - Shaikha Y Almaazmi
- Faculty of Health Sciences, Higher Colleges of Technology, Sharjah, United Arab Emirates
| | - Sahar Arafa
- Faculty of Health Sciences, Higher Colleges of Technology, Sharjah, United Arab Emirates
| | - Gregory L Blatch
- Faculty of Health Sciences, Higher Colleges of Technology, Sharjah, United Arab Emirates; Biomedical Biotechnology Research Unit, Department of Biochemistry and Microbiology, Rhodes University, Grahamstown, South Africa.
| | - Tanima Dutta
- Department of Diagnostic Genomics, Pathwest, QEII Medical Centre, Nedlands, Western Australia, Australia
| | - Jason E Gestwicki
- Department of Pharmaceutical Chemistry and the Institute for Neurodegenerative Diseases, University of California San Francisco, San Francisco, CA, USA
| | - Robert A Keyzers
- Centre for Biodiscovery & School of Chemical and Physical Sciences, Victoria University of Wellington, Wellington, New Zealand
| | - Addmore Shonhai
- Department of Biochemistry and Microbiology, University of Venda, Thohoyandou, South Africa
| | - Harpreet Singh
- Department of Bioinformatics, Hans Raj Mahila Maha Vidyalaya, Jalandhar, Punjab, India
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2
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Sahu W, Bai T, Das A, Mukherjee S, Prusty A, Mallick NR, Elangovan S, Reddy KS. Plasmodium falciparum J-dot localized J domain protein A8iJp modulates the chaperone activity of human HSPA8. FEBS Lett 2024; 598:818-836. [PMID: 38418371 DOI: 10.1002/1873-3468.14836] [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: 09/13/2023] [Revised: 01/25/2024] [Accepted: 02/04/2024] [Indexed: 03/01/2024]
Abstract
Plasmodium falciparum renovates the host erythrocyte to survive during intraerythrocytic development. This renovation requires many parasite proteins to unfold and move outside the parasitophorous vacuolar membrane, and chaperone-regulated protein folding becomes essential for the exported proteins to function. We report on a type-IV J domain protein (JDP), PF3D7_1401100, which we found to be processed before export and trafficked inside the lumen of parasite-derived structures known as J-dots. We found this protein to have holdase activity, as well as stimulate the ATPase and aggregation suppression activity of the human HSP70 chaperone HsHSPA8; thus, we named it "HSPA8-interacting J protein" (A8iJp). Moreover, we found a subset of HsHSPA8 to co-localize with A8iJp inside the infected human erythrocyte. Our results suggest that A8iJp modulates HsHSPA8 chaperone activity and may play an important role in host erythrocyte renovation.
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Affiliation(s)
- Welka Sahu
- School of Biotechnology, Kalinga Institute of Industrial Technology, Deemed to be University, Bhubaneswar, India
| | - Tapaswini Bai
- School of Biotechnology, Kalinga Institute of Industrial Technology, Deemed to be University, Bhubaneswar, India
| | - Aleena Das
- School of Biotechnology, Kalinga Institute of Industrial Technology, Deemed to be University, Bhubaneswar, India
| | - Subhadip Mukherjee
- School of Biotechnology, Kalinga Institute of Industrial Technology, Deemed to be University, Bhubaneswar, India
| | - Aradhana Prusty
- School of Biotechnology, Kalinga Institute of Industrial Technology, Deemed to be University, Bhubaneswar, India
| | - Nipa Rani Mallick
- School of Biotechnology, Kalinga Institute of Industrial Technology, Deemed to be University, Bhubaneswar, India
| | - Selvakumar Elangovan
- School of Biotechnology, Kalinga Institute of Industrial Technology, Deemed to be University, Bhubaneswar, India
| | - K Sony Reddy
- School of Biotechnology, Kalinga Institute of Industrial Technology, Deemed to be University, Bhubaneswar, India
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Zimbres FM, Merino EF, Butschek GJ, Butler JH, Ducongé F, Cassera MB. Aptamer-Based Imaging of Polyisoprenoids in the Malaria Parasite. Molecules 2023; 29:178. [PMID: 38202761 PMCID: PMC10780415 DOI: 10.3390/molecules29010178] [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: 11/29/2023] [Revised: 12/21/2023] [Accepted: 12/22/2023] [Indexed: 01/12/2024] Open
Abstract
Dolichols are isoprenoid end-products of the mevalonate and 2C-methyl-D-erythritol-4-phosphate pathways. The synthesis of dolichols is initiated with the addition of several molecules of isopentenyl diphosphate to farnesyl diphosphate. This reaction is catalyzed by a cis-prenyltransferase and leads to the formation of polyprenyl diphosphate. Subsequent steps involve the dephosphorylation and reduction of the α-isoprene unit by a polyprenol reductase, resulting in the generation of dolichol. The size of the dolichol varies, depending on the number of isoprene units incorporated. In eukaryotes, dolichols are synthesized as a mixture of four or more different lengths. Their biosynthesis is predicted to occur in the endoplasmic reticulum, where dolichols play an essential role in protein glycosylation. In this study, we have developed a selection of aptamers targeting dolichols and enhanced their specificity by incorporating fatty acids for negative selection. One aptamer showed high enrichment and specificity for linear polyisoprenoids containing at least one oxygen atom, such as an alcohol or aldehyde, in the α-isoprene unit. The selected aptamer proved to be a valuable tool for the subcellular localization of polyisoprenoids in the malaria parasite. To the best of our knowledge, this is the first time that polyisoprenoids have been localized within a cell using aptamer-based imaging techniques.
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Affiliation(s)
- Flavia M. Zimbres
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA
- Center for Tropical and Emerging Global Diseases (CTEGD), University of Georgia, Athens, GA 30602, USA
| | - Emilio F. Merino
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA
- Center for Tropical and Emerging Global Diseases (CTEGD), University of Georgia, Athens, GA 30602, USA
| | - Grant J. Butschek
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA
- Center for Tropical and Emerging Global Diseases (CTEGD), University of Georgia, Athens, GA 30602, USA
| | - Joshua H. Butler
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA
- Center for Tropical and Emerging Global Diseases (CTEGD), University of Georgia, Athens, GA 30602, USA
| | - Frédéric Ducongé
- French Atomic Energy Commission (CEA), Fundamental Research Division (DRF), Institute of Biology François Jacob (Jacob), Molecular Imaging Research Center, 92265 Fontenay-aux-Roses, France
- Neurodegenerative Diseases Laboratory, CNRS CEA UMR 9199, 92265 Fontenay-aux-Roses, France
- Paris-Saclay University, 92265 Fontenay-aux-Roses, France
| | - Maria B. Cassera
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA
- Center for Tropical and Emerging Global Diseases (CTEGD), University of Georgia, Athens, GA 30602, USA
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4
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Anaguano D, Dedkhad W, Brooks CF, Cobb DW, Muralidharan V. Time-resolved proximity biotinylation implicates a porin protein in export of transmembrane malaria parasite effectors. J Cell Sci 2023; 136:jcs260506. [PMID: 37772444 PMCID: PMC10651097 DOI: 10.1242/jcs.260506] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Accepted: 09/21/2023] [Indexed: 09/30/2023] Open
Abstract
The malaria-causing parasite, Plasmodium falciparum completely remodels its host red blood cell (RBC) through the export of several hundred parasite proteins, including transmembrane proteins, across multiple membranes to the RBC. However, the process by which these exported membrane proteins are extracted from the parasite plasma membrane for export remains unknown. To address this question, we fused the exported membrane protein, skeleton binding protein 1 (SBP1), with TurboID, a rapid, efficient and promiscuous biotin ligase (SBP1TbID). Using time-resolved proximity biotinylation and label-free quantitative proteomics, we identified two groups of SBP1TbID interactors - early interactors (pre-export) and late interactors (post-export). Notably, two promising membrane-associated proteins were identified as pre-export interactors, one of which possesses a predicted translocon domain, that could facilitate the export of membrane proteins. Further investigation using conditional mutants of these candidate proteins showed that these proteins were essential for asexual growth and localize to the host-parasite interface during early stages of the intraerythrocytic cycle. These data suggest that they might play a role in ushering membrane proteins from the parasite plasma membrane for export to the host RBC.
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Affiliation(s)
- David Anaguano
- Department of Cellular Biology, University of Georgia, Athens, GA, USA
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA
| | - Watcharatip Dedkhad
- Department of Cellular Biology, University of Georgia, Athens, GA, USA
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA
| | - Carrie F Brooks
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA
| | - David W Cobb
- Department of Cellular Biology, University of Georgia, Athens, GA, USA
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA
| | - Vasant Muralidharan
- Department of Cellular Biology, University of Georgia, Athens, GA, USA
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA
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Mansour H, Cabezas-Cruz A, Peucelle V, Farce A, Salomé-Desnoulez S, Metatla I, Guerrera IC, Hollin T, Khalife J. Characterization of GEXP15 as a Potential Regulator of Protein Phosphatase 1 in Plasmodium falciparum. Int J Mol Sci 2023; 24:12647. [PMID: 37628837 PMCID: PMC10454571 DOI: 10.3390/ijms241612647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 07/29/2023] [Accepted: 08/04/2023] [Indexed: 08/27/2023] Open
Abstract
The Protein Phosphatase type 1 catalytic subunit (PP1c) (PF3D7_1414400) operates in combination with various regulatory proteins to specifically direct and control its phosphatase activity. However, there is little information about this phosphatase and its regulators in the human malaria parasite, Plasmodium falciparum. To address this knowledge gap, we conducted a comprehensive investigation into the structural and functional characteristics of a conserved Plasmodium-specific regulator called Gametocyte EXported Protein 15, GEXP15 (PF3D7_1031600). Through in silico analysis, we identified three significant regions of interest in GEXP15: an N-terminal region housing a PP1-interacting RVxF motif, a conserved domain whose function is unknown, and a GYF-like domain that potentially facilitates specific protein-protein interactions. To further elucidate the role of GEXP15, we conducted in vitro interaction studies that demonstrated a direct interaction between GEXP15 and PP1 via the RVxF-binding motif. This interaction was found to enhance the phosphatase activity of PP1. Additionally, utilizing a transgenic GEXP15-tagged line and live microscopy, we observed high expression of GEXP15 in late asexual stages of the parasite, with localization predominantly in the nucleus. Immunoprecipitation assays followed by mass spectrometry analyses revealed the interaction of GEXP15 with ribosomal- and RNA-binding proteins. Furthermore, through pull-down analyses of recombinant functional domains of His-tagged GEXP15, we confirmed its binding to the ribosomal complex via the GYF domain. Collectively, our study sheds light on the PfGEXP15-PP1-ribosome interaction, which plays a crucial role in protein translation. These findings suggest that PfGEXP15 could serve as a potential target for the development of malaria drugs.
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Affiliation(s)
- Hala Mansour
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019-UMR 9017-CIIL-Center for Infection and Immunity of Lille, 59000 Lille, France; (H.M.); (V.P.)
| | - Alejandro Cabezas-Cruz
- ANSES, INRAE, Ecole Nationale Vétérinaire d’Alfort, UMR BIPAR, Laboratoire de Santé Animale, 94700 Maisons-Alfort, France;
| | - Véronique Peucelle
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019-UMR 9017-CIIL-Center for Infection and Immunity of Lille, 59000 Lille, France; (H.M.); (V.P.)
| | - Amaury Farce
- Univ. Lille, Inserm, CHU Lille, U1286–Infinite–Institute for Translational Research in Inflammation, 59000 Lille, France;
| | - Sophie Salomé-Desnoulez
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, US 41–UAR 2014–PLBS, 59000 Lille, France;
| | - Ines Metatla
- Proteomics Platform Necker, Université Paris Cité–Structure Fédérative de Recherche Necker, INSERM US24/CNRS UAR3633, 75015 Paris, France; (I.M.); (I.C.G.)
| | - Ida Chiara Guerrera
- Proteomics Platform Necker, Université Paris Cité–Structure Fédérative de Recherche Necker, INSERM US24/CNRS UAR3633, 75015 Paris, France; (I.M.); (I.C.G.)
| | - Thomas Hollin
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019-UMR 9017-CIIL-Center for Infection and Immunity of Lille, 59000 Lille, France; (H.M.); (V.P.)
- Department of Molecular, Cell and Systems Biology, University of California Riverside, Riverside, CA 92521, USA
| | - Jamal Khalife
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019-UMR 9017-CIIL-Center for Infection and Immunity of Lille, 59000 Lille, France; (H.M.); (V.P.)
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6
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Pires CV, Oberstaller J, Wang C, Casandra D, Zhang M, Chawla J, Adapa SR, Otto TD, Ferdig MT, Rayner JC, Jiang RHY, Adams JH. Chemogenomic Profiling of a Plasmodium falciparum Transposon Mutant Library Reveals Shared Effects of Dihydroartemisinin and Bortezomib on Lipid Metabolism and Exported Proteins. Microbiol Spectr 2023; 11:e0501422. [PMID: 37067430 PMCID: PMC10269874 DOI: 10.1128/spectrum.05014-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Accepted: 03/21/2023] [Indexed: 04/18/2023] Open
Abstract
The antimalarial activity of the frontline drug artemisinin involves generation of reactive oxygen species (ROS) leading to oxidative damage of parasite proteins. To achieve homeostasis and maintain protein quality control in the overwhelmed parasite, the ubiquitin-proteasome system kicks in. Even though molecular markers for artemisinin resistance like pfkelch13 have been identified, the intricate network of mechanisms driving resistance remains to be elucidated. Here, we report a forward genetic screening strategy that enables a broader identification of genetic factors responsible for altering sensitivity to dihydroartemisinin (DHA) and a proteasome inhibitor, bortezomib (BTZ). Using a library of isogenic piggyBac mutants in P. falciparum, we defined phenotype-genotype associations influencing drug responses and highlighted shared mechanisms between the two processes, which mainly included proteasome-mediated degradation and the lipid metabolism genes. Additional transcriptomic analysis of a DHA/BTZ-sensitive piggyBac mutant showed it is possible to find differences between the two response mechanisms on the specific components for regulation of the exportome. Our results provide further insight into the molecular mechanisms of antimalarial drug resistance. IMPORTANCE Malaria control is seriously threatened by the emergence and spread of Plasmodium falciparum resistance to the leading antimalarial, artemisinin. The potent killing activity of artemisinin results from oxidative damage unleashed by free heme activation released by hemoglobin digestion. Although the ubiquitin-proteasome system is considered critical for parasite survival of this toxicity, the diverse genetic changes linked to artemisinin resistance are complex and, so far, have not included the ubiquitin-proteasome system. In this study, we use a systematic forward genetic approach by screening a library of P. falciparum random piggyBac mutants to decipher the genetic factors driving malaria parasite responses to the oxidative stress caused by antimalarial drugs. This study compares phenotype-genotype associations influencing dihydroartemisinin responses with the proteasome inhibitor bortezomib to delineate the role of ubiquitin-proteasome system. Our study highlights shared and unique pathways from the complex array of molecular processes critical for P. falciparum survival resulting from the oxidative damage of artemisinin.
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Affiliation(s)
- Camilla Valente Pires
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, Tampa, Florida, USA
- USF Genomics Program, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Jenna Oberstaller
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, Tampa, Florida, USA
- USF Genomics Program, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Chengqi Wang
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, Tampa, Florida, USA
- USF Genomics Program, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Debora Casandra
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, Tampa, Florida, USA
- USF Genomics Program, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Min Zhang
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, Tampa, Florida, USA
- USF Genomics Program, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Jyotsna Chawla
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, Tampa, Florida, USA
- USF Genomics Program, College of Public Health, University of South Florida, Tampa, Florida, USA
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States
| | - Swamy Rakesh Adapa
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, Tampa, Florida, USA
- USF Genomics Program, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Thomas D. Otto
- Institute of Infection, Immunity and Inflammation, MVLS, University of Glasgow, Glasgow, United Kingdom
| | - Michael T. Ferdig
- Eck Institute for Global Health, Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA
| | - Julian C. Rayner
- Cambridge Institute for Medical Research, Cambridge Biomedical Campus, University of Cambridge, Cambridge, United Kingdom
| | - Rays H. Y. Jiang
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, Tampa, Florida, USA
- USF Genomics Program, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - John H. Adams
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, Tampa, Florida, USA
- USF Genomics Program, College of Public Health, University of South Florida, Tampa, Florida, USA
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Barth J, Schach T, Przyborski JM. HSP70 and their co-chaperones in the human malaria parasite P. falciparum and their potential as drug targets. Front Mol Biosci 2022; 9:968248. [PMID: 35992276 PMCID: PMC9388776 DOI: 10.3389/fmolb.2022.968248] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 07/04/2022] [Indexed: 11/13/2022] Open
Abstract
As part of their life-cycle, malaria parasites undergo rapid cell multiplication and division, with one parasite giving rise to over 20 new parasites within the course of 48 h. To support this, the parasite has an extremely high metabolic rate and level of protein biosynthesis. Underpinning these activities, the parasite encodes a number of chaperone/heat shock proteins, belonging to various families. Research over the past decade has revealed that these proteins are involved in a number of essential processes within the parasite, or within the infected host cell. Due to this, these proteins are now being viewed as potential targets for drug development, and we have begun to characterize their properties in more detail. In this article we summarize the current state of knowledge about one particular chaperone family, that of the HSP70, and highlight their importance, function, and potential co-chaperone interactions. This is then discussed with regard to the suitability of these proteins and interactions for drug development.
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Blatch GL. Plasmodium falciparum Molecular Chaperones: Guardians of the Malaria Parasite Proteome and Renovators of the Host Proteome. Front Cell Dev Biol 2022; 10:921739. [PMID: 35652103 PMCID: PMC9149364 DOI: 10.3389/fcell.2022.921739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Accepted: 04/28/2022] [Indexed: 11/13/2022] Open
Abstract
Plasmodium falciparum is a unicellular protozoan parasite and causative agent of the most severe form of malaria in humans. The malaria parasite has had to develop sophisticated mechanisms to preserve its proteome under the changing stressful conditions it confronts, particularly when it invades host erythrocytes. Heat shock proteins, especially those that function as molecular chaperones, play a key role in protein homeostasis (proteostasis) of P. falciparum. Soon after invading erythrocytes, the malaria parasite exports a large number of proteins including chaperones, which are responsible for remodeling the infected erythrocyte to enable its survival and pathogenesis. The infected host cell has parasite-resident and erythrocyte-resident chaperones, which appear to play a vital role in the folding and functioning of P. falciparum proteins and potentially host proteins. This review critiques the current understanding of how the major chaperones, particularly the Hsp70 and Hsp40 (or J domain proteins, JDPs) families, contribute to proteostasis of the malaria parasite-infected erythrocytes.
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Affiliation(s)
- Gregory L Blatch
- The Vice Chancellery, The University of Notre Dame Australia, Fremantle, WA, Australia.,Biomedical Biotechnology Research Unit, Department of Biochemistry and Microbiology, Rhodes University, Grahamstown, South Africa.,Biomedical Research and Drug Discovery Research Group, Faculty of Health Sciences, Higher Colleges of Technology, Sharjah, United Arab Emirates
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9
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Sahu W, Bai T, Panda PK, Mazumder A, Das A, Ojha DK, Verma SK, Elangovan S, Reddy KS. Plasmodium falciparum HSP40 protein eCiJp traffics to the erythrocyte cytoskeleton and interacts with the human HSP70 chaperone HSPA1. FEBS Lett 2022; 596:95-111. [PMID: 34890056 DOI: 10.1002/1873-3468.14255] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 11/24/2021] [Accepted: 12/02/2021] [Indexed: 11/09/2022]
Abstract
Renovation of host erythrocytes is vital for pathogenesis by Plasmodium falciparum. These changes are mediated by parasite proteins that translocate beyond the parasitophorous vacuolar membrane in an unfolded state, suggesting protein folding by chaperones is imperative for the functionality of exported proteins. We report a type IV P. falciparum heat-shock protein 40, PF11_0034, that localizes to the cytoplasmic side of J-dots and interacts with the erythrocyte cytoskeleton, and therefore named eCiJp (erythrocyte cytoskeleton-interacting J protein). Recombinant eCiJp binds to the human heat-shock protein 70 HsHSPA1 and promotes its ATPase activity. In addition, eCiJp could suppress protein aggregation. Our data suggest that eCiJp recruits HsHSPA1 to the host erythrocyte cytoskeleton, where it may become involved in remodeling of the erythrocyte cytoskeleton and/or folding of exported parasite proteins.
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Affiliation(s)
- Welka Sahu
- School of Biotechnology, Kalinga Institute of Industrial Technology, Deemed to be University, Bhubaneswar, India
| | - Tapaswini Bai
- School of Biotechnology, Kalinga Institute of Industrial Technology, Deemed to be University, Bhubaneswar, India
| | - Pritam Kumar Panda
- Condensed Matter Theory Group, Materials Theory Division, Department of Physics and Astronomy, Uppsala University, Sweden
| | - Archita Mazumder
- School of Biotechnology, Kalinga Institute of Industrial Technology, Deemed to be University, Bhubaneswar, India
| | - Aleena Das
- School of Biotechnology, Kalinga Institute of Industrial Technology, Deemed to be University, Bhubaneswar, India
- Technology Business Incubator, Kalinga Institute of Industrial Technology, Deemed to be University, Bhubaneswar, India
| | - Deepak Kumar Ojha
- School of Biotechnology, Kalinga Institute of Industrial Technology, Deemed to be University, Bhubaneswar, India
| | - Suresh K Verma
- School of Biotechnology, Kalinga Institute of Industrial Technology, Deemed to be University, Bhubaneswar, India
| | - Selvakumar Elangovan
- School of Biotechnology, Kalinga Institute of Industrial Technology, Deemed to be University, Bhubaneswar, India
| | - K Sony Reddy
- School of Biotechnology, Kalinga Institute of Industrial Technology, Deemed to be University, Bhubaneswar, India
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10
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Co-chaperone involvement in knob biogenesis implicates host-derived chaperones in malaria virulence. PLoS Pathog 2021; 17:e1009969. [PMID: 34614006 PMCID: PMC8544838 DOI: 10.1371/journal.ppat.1009969] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 10/25/2021] [Accepted: 09/24/2021] [Indexed: 11/19/2022] Open
Abstract
The pathology associated with malaria infection is largely due to the ability of infected human RBCs to adhere to a number of receptors on endothelial cells within tissues and organs. This phenomenon is driven by the export of parasite-encoded proteins to the host cell, the exact function of many of which is still unknown. Here we inactivate the function of one of these exported proteins, PFA66, a member of the J-domain protein family. Although parasites lacking this protein were still able to grow in cell culture, we observed severe defects in normal host cell modification, including aberrant morphology of surface knobs, disrupted presentation of the cytoadherence molecule PfEMP1, and a total lack of cytoadherence, despite the presence of the knob associated protein KAHRP. Complementation assays demonstrate that an intact J-domain is required for recovery to a wild-type phenotype and suggest that PFA66 functions in concert with a HSP70 to carry out host cell modification. Strikingly, this HSP70 is likely to be of host origin. ATPase assays on recombinant protein verify a functional interaction between PFA66 and residual host cell HSP70. Taken together, our data reveal a role for PFA66 in host cell modification, strongly implicate human HSP70s as being essential in this process and uncover a new KAHRP-independent molecular factor required for correct knob biogenesis. To survive in the human body, the malaria parasite invades and lives within human red blood cells. Once within the red blood cell, the parasite renovates the host cell to its own needs. Here we have studied which factors from both parasite and host cell are required for this renovation process, and discover that human chaperone proteins, referred to as HSP70, are required. It appears that a particular parasite-derived protein, PFA66, recruits and modifies the function of the human HSP70. As this interaction between a parasite and human protein is novel and essential for parasite survival, our study identifies a potential Achilles’ Heel which may be targeted for development of new anti-malaria therapies.
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Daniyan MO. Heat Shock Proteins as Targets for Novel Antimalarial Drug Discovery. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1340:205-236. [PMID: 34569027 DOI: 10.1007/978-3-030-78397-6_9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Plasmodium falciparum, the parasitic agent that is responsible for a severe and dangerous form of human malaria, has a history of long years of cohabitation with human beings with attendant negative consequences. While there have been some gains in the fight against malaria through the application of various control measures and the use of chemotherapeutic agents, and despite the global decline in malaria cases and associated deaths, the continual search for new and effective therapeutic agents is key to achieving sustainable development goals. An important parasite survival strategy, which is also of serious concern to the scientific community, is the rate at which the parasites continually develop resistance to drugs. Among the key players in the parasite's ability to develop resistance, maintain cellular integrity, and survives within an unusual environment of the red blood cells are the molecular chaperones of the heat shock proteins (HSP) family. HSPs constitute a novel avenue for antimalarial drug discovery and by exploring their ubiquitous nature and multifunctional activities, they may be suitable targets for the discovery of multi-targets antimalarial drugs, needed to fight incessant drug resistance. In this chapter, features of selected families of plasmodial HSPs that can be exploited in drug discovery are presented. Also, known applications of HSPs in small molecule screening, their potential usefulness in high throughput drug screening, as well as possible challenges are highlighted.
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Affiliation(s)
- Michael Oluwatoyin Daniyan
- Department of Pharmacology, Faculty of Pharmacy, Obafemi Awolowo University, Ile-Ife, Osun State, Nigeria.
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12
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The Role of Hsp70s in the Development and Pathogenicity of Plasmodium falciparum. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021. [PMID: 34569021 DOI: 10.1007/978-3-030-78397-6_3] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/24/2024]
Abstract
The main agent of human malaria, the protozoa, Plasmodium falciparum is known to infect liver cells, subsequently invading the host erythrocyte, leading to the manifestation of clinical outcomes of the disease. As part of its survival in the human host, P. falciparum employs several heat shock protein (Hsp) families whose primary purpose is to ensure cytoprotection through their molecular chaperone role. The parasite expresses six Hsp70s that localise to various subcellular organelles of the parasite, with one, PfHsp70-x, being exported to the infected human erythrocyte. The role of these Hsp70s in the survival and pathogenicity of malaria has received immense research attention. Several studies have reported on their structure-function features, network partnerships, and elucidation of their potential substrates. Apart from their role in cytoprotection and pathogenicity, Hsp70s are implicated in antimalarial drug resistance. As such, they are deemed potential antimalarial drug candidates, especially suited for co-targeting in combination therapies. In addition, Hsp70 is implicated in host immune modulation. The current report highlights the various structure-function features of these proteins, their roles in the development of malaria, current and prospective efforts being employed towards targeting them in malaria intervention efforts.
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13
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Okombo J, Kanai M, Deni I, Fidock DA. Genomic and Genetic Approaches to Studying Antimalarial Drug Resistance and Plasmodium Biology. Trends Parasitol 2021; 37:476-492. [PMID: 33715941 PMCID: PMC8162148 DOI: 10.1016/j.pt.2021.02.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 02/11/2021] [Accepted: 02/12/2021] [Indexed: 12/14/2022]
Abstract
Recent progress in genomics and molecular genetics has empowered novel approaches to study gene functions in disease-causing pathogens. In the human malaria parasite Plasmodium falciparum, the application of genome-based analyses, site-directed genome editing, and genetic systems that allow for temporal and quantitative regulation of gene and protein expression have been invaluable in defining the genetic basis of antimalarial resistance and elucidating candidate targets to accelerate drug discovery efforts. Using examples from recent studies, we review applications of some of these approaches in advancing our understanding of Plasmodium biology and illustrate their contributions and limitations in characterizing parasite genomic loci associated with antimalarial drug responses.
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Affiliation(s)
- John Okombo
- Department of Microbiology & Immunology, Department of Medicine, Columbia University Irving Medical Center, New York, NY, USA
| | - Mariko Kanai
- Department of Microbiology & Immunology, Department of Medicine, Columbia University Irving Medical Center, New York, NY, USA
| | - Ioanna Deni
- Department of Microbiology & Immunology, Department of Medicine, Columbia University Irving Medical Center, New York, NY, USA
| | - David A Fidock
- Department of Microbiology & Immunology, Department of Medicine, Columbia University Irving Medical Center, New York, NY, USA; Division of Infectious Diseases, Department of Medicine, Columbia University Irving Medical Center, New York, NY, USA.
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14
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Abstract
Malaria, caused by infection with Plasmodium parasites, remains a significant global health concern. For decades, genetic intractability and limited tools hindered our ability to study essential proteins and pathways in Plasmodium falciparum, the parasite associated with the most severe malaria cases. However, recent years have seen major leaps forward in the ability to genetically manipulate P. falciparum parasites and conditionally control protein expression/function. The conditional knockdown systems used in P. falciparum target all 3 components of the central dogma, allowing researchers to conditionally control gene expression, translation, and protein function. Here, we review some of the common knockdown systems that have been adapted or developed for use in P. falciparum. Much of the work done using conditional knockdown approaches has been performed in asexual, blood-stage parasites, but we also highlight their uses in other parts of the life cycle and discuss new ways of applying these systems outside of the intraerythrocytic stages. With the use of these tools, the field’s understanding of parasite biology is ever increasing, and promising new pathways for antimalarial drug development are being discovered.
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Abstract
Obligate intracellular malaria parasites reside within a vacuolar compartment generated during invasion which is the principal interface between pathogen and host. To subvert their host cell and support their metabolism, these parasites coordinate a range of transport activities at this membrane interface that are critically important to parasite survival and virulence, including nutrient import, waste efflux, effector protein export, and uptake of host cell cytosol. Here, we review our current understanding of the transport mechanisms acting at the malaria parasite vacuole during the blood and liver-stages of development with a particular focus on recent advances in our understanding of effector protein translocation into the host cell by the Plasmodium Translocon of EXported proteins (PTEX) and small molecule transport by the PTEX membrane-spanning pore EXP2. Comparison to Toxoplasma gondii and other related apicomplexans is provided to highlight how similar and divergent mechanisms are employed to fulfill analogous transport activities.
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Affiliation(s)
- Josh R. Beck
- Department of Biomedical Sciences, Iowa State University, Ames, Iowa, United States of America
| | - Chi-Min Ho
- Department of Microbiology and Immunology, Vagelos College of Physicians and Surgeons, Columbia University, New York, New York, United States of America
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16
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Kirti A, Sharma M, Rani K, Bansal A. CRISPRing protozoan parasites to better understand the biology of diseases. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2021; 180:21-68. [PMID: 33934837 DOI: 10.1016/bs.pmbts.2021.01.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Precise gene editing techniques are paramount to gain deeper insights into the biological processes such as host-parasite interactions, drug resistance mechanisms, and gene-function relationships. Discovery of CRISPR-Cas9 system has spearheaded mechanistic understanding of protozoan parasite biology as evident from the number of reports in the last decade. Here, we have described the use of CRISPR-Cas9 in understanding the biology of medically important protozoan parasites such as Plasmodium, Leishmania, Trypanosoma, Babesia and Trichomonas. In spite of intrinsic difficulties in genome editing in these protozoan parasites, CRISPR-Cas9 has acted as a catalyst for faster generation of desired transgenic parasites. Modifications in the CRISPR-Cas9 system for improving the efficiency have been useful in better understanding the molecular mechanisms associated with repair of double strand breaks in the parasites. Moreover, improvement in reagents used for CRISPR mediated gene editing have been instrumental in addressing the issue of non-specificity and toxicity for therapeutic use. These application-based modifications may help in further increasing the efficiency of gene editing in protozoan parasites.
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Affiliation(s)
- Apurva Kirti
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Manish Sharma
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Komal Rani
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Abhisheka Bansal
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India.
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17
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Structural-functional diversity of malaria parasite's PfHSP70-1 and PfHSP40 chaperone pair gives an edge over human orthologs in chaperone-assisted protein folding. Biochem J 2021; 477:3625-3643. [PMID: 32893851 DOI: 10.1042/bcj20200434] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 09/02/2020] [Accepted: 09/07/2020] [Indexed: 12/13/2022]
Abstract
Plasmodium falciparum, the human malaria parasite harbors a metastable proteome which is vulnerable to proteotoxic stress conditions encountered during its lifecycle. How parasite's chaperone machinery is able to maintain its aggregation-prone proteome in functional state, is poorly understood. As HSP70-40 system forms the central hub in cellular proteostasis, we investigated the protein folding capacity of PfHSP70-1 and PfHSP40 chaperone pair and compared it with human orthologs (HSPA1A and DNAJA1). Despite the structural similarity, we observed that parasite chaperones and their human orthologs exhibit striking differences in conformational dynamics. Comprehensive biochemical investigations revealed that PfHSP70-1 and PfHSP40 chaperone pair has better protein folding, aggregation inhibition, oligomer remodeling and disaggregase activities than their human orthologs. Chaperone-swapping experiments suggest that PfHSP40 can also efficiently cooperate with human HSP70 to facilitate the folding of client-substrate. SPR-derived kinetic parameters reveal that PfHSP40 has higher binding affinity towards unfolded substrate than DNAJA1. Interestingly, the observed slow dissociation rate of PfHSP40-substrate interaction allows PfHSP40 to maintain the substrate in folding-competent state to minimize its misfolding. Structural investigation through small angle x-ray scattering gave insights into the conformational architecture of PfHSP70-1 (monomer), PfHSP40 (dimer) and their complex. Overall, our data suggest that the parasite has evolved functionally diverged and efficient chaperone machinery which allows the human malaria parasite to survive in hostile conditions. The distinct allosteric landscapes and interaction kinetics of plasmodial chaperones open avenues for the exploration of small-molecule based antimalarial interventions.
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18
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Cobb DW, Kudyba HM, Villegas A, Hoopmann MR, Baptista RP, Bruton B, Krakowiak M, Moritz RL, Muralidharan V. A redox-active crosslinker reveals an essential and inhibitable oxidative folding network in the endoplasmic reticulum of malaria parasites. PLoS Pathog 2021; 17:e1009293. [PMID: 33534803 PMCID: PMC7886143 DOI: 10.1371/journal.ppat.1009293] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 02/16/2021] [Accepted: 01/07/2021] [Indexed: 12/18/2022] Open
Abstract
Malaria remains a major global health problem, creating a constant need for research to identify druggable weaknesses in P. falciparum biology. As important components of cellular redox biology, members of the Thioredoxin (Trx) superfamily of proteins have received interest as potential drug targets in Apicomplexans. However, the function and essentiality of endoplasmic reticulum (ER)-localized Trx-domain proteins within P. falciparum has not been investigated. We generated conditional mutants of the protein PfJ2—an ER chaperone and member of the Trx superfamily—and show that it is essential for asexual parasite survival. Using a crosslinker specific for redox-active cysteines, we identified PfJ2 substrates as PfPDI8 and PfPDI11, both members of the Trx superfamily as well, which suggests a redox-regulatory role for PfJ2. Knockdown of these PDIs in PfJ2 conditional mutants show that PfPDI11 may not be essential. However, PfPDI8 is required for asexual growth and our data suggest it may work in a complex with PfJ2 and other ER chaperones. Finally, we show that the redox interactions between these Trx-domain proteins in the parasite ER and their substrates are sensitive to small molecule inhibition. Together these data build a model for how Trx-domain proteins in the P. falciparum ER work together to assist protein folding and demonstrate the suitability of ER-localized Trx-domain proteins for antimalarial drug development. One of the leading and persistent causes of childhood mortality in the world is malaria, which is caused by parasites from the genus Plasmodium. Unfortunately, the parasite has developed resistance to all available drugs, making the discovery of new drug targets and potential small molecule inhibitors of essential parasite biology a top priority. A critical pathway required for many different biological processes in the parasite is oxidative folding which requires members of the Thioredoxin (Trx) superfamily of proteins. But we know almost nothing about the function and essentiality of Trx-domain proteins that localize to the endoplasmic reticulum, the origin of the secretory pathway, within P. falciparum. Here we show that a network of Trx-domain containing proteins function together and are essential for parasite survival within human red blood cells. Further, we identify a small molecule inhibitor of the redox activities of these Trx-domain containing proteins. This study demonstrates the suitability of this pathway for future antimalarial drug development.
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Affiliation(s)
- David W. Cobb
- Department of Cellular Biology, University of Georgia, Georgia, United States of America
- Center for Tropical and Emerging Global Diseases, University of Georgia, Georgia, United States of America
| | - Heather M. Kudyba
- Department of Cellular Biology, University of Georgia, Georgia, United States of America
- Center for Tropical and Emerging Global Diseases, University of Georgia, Georgia, United States of America
| | - Alejandra Villegas
- Department of Cellular Biology, University of Georgia, Georgia, United States of America
- Center for Tropical and Emerging Global Diseases, University of Georgia, Georgia, United States of America
| | - Michael R. Hoopmann
- Institute for Systems Biology, Seattle, Washington, United States of America
| | - Rodrigo P. Baptista
- Center for Tropical and Emerging Global Diseases, University of Georgia, Georgia, United States of America
- Institute of Bioinformatics, University of Georgia, Georgia, United States of America
| | - Baylee Bruton
- Department of Cellular Biology, University of Georgia, Georgia, United States of America
| | - Michelle Krakowiak
- Department of Cellular Biology, University of Georgia, Georgia, United States of America
- Center for Tropical and Emerging Global Diseases, University of Georgia, Georgia, United States of America
| | - Robert L. Moritz
- Institute for Systems Biology, Seattle, Washington, United States of America
| | - Vasant Muralidharan
- Department of Cellular Biology, University of Georgia, Georgia, United States of America
- Center for Tropical and Emerging Global Diseases, University of Georgia, Georgia, United States of America
- * E-mail:
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19
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Role of the J Domain Protein Family in the Survival and Pathogenesis of Plasmodium falciparum. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1340:97-123. [PMID: 34569022 DOI: 10.1007/978-3-030-78397-6_4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Plasmodium falciparum has dedicated an unusually large proportion of its genome to molecular chaperones (2% of all genes), with the heat shock protein 40 (Hsp40) family (now called J domain proteins, JDPs) exhibiting evolutionary radiation into 49 members. A large number of the P. falciparum JDPs (PfJDPs) are predicted to be exported, with certain members shown experimentally to be present in the erythrocyte cytosol (PFA0660w and PFE0055c) or erythrocyte membrane (ring-infected erythrocyte surface antigen, RESA). PFA0660w and PFE0055c are associated with an exported plasmodial Hsp70 (PfHsp70-x) within novel mobile structures called J-dots, which have been proposed to be dedicated to the trafficking of key membrane proteins such as erythrocyte membrane protein 1 (PfEMP1). Well over half of the PfJDPs appear to be essential, including the J-dot PfJDP, PFE0055c, while others have been found to be required for growth under febrile conditions (e.g. PFA0110w, the ring-infected erythrocyte surface antigen protein [RESA]) or involved in pathogenesis (e.g. PF10_0381 has been shown to be important for protrusions of the infected red blood cell membrane, the so-called knobs). Here we review what is known about those PfJDPs that have been well characterised, and may be directly or indirectly involved in the survival and pathogenesis of the malaria parasite.
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20
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Jonsdottir TK, Gabriela M, Gilson PR. The Role of Malaria Parasite Heat Shock Proteins in Protein Trafficking and Remodelling of Red Blood Cells. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1340:141-167. [PMID: 34569024 DOI: 10.1007/978-3-030-78397-6_6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The genus Plasmodium comprises intracellular eukaryotic parasites that infect many vertebrate groups and cause deadly malaria disease in humans. The parasites employ a suite of heat shock proteins to help traffic other proteins to different compartments within their own cells and that of the host cells they parasitise. This review will cover the role of these chaperones in protein export and host cell modification in the asexual blood stage of the human parasite P. falciparum which is the most deadly and well-studied parasite species. We will examine the role chaperones play in the import of proteins into the secretory pathway from where they are escorted to the vacuole space surrounding the intraerythrocytic parasite. Here, other heat shock proteins unfold protein cargoes and extrude them into the red blood cell (RBC) cytosol from where additional chaperones of parasite and possibly host origin refold the cargo proteins and guide them to their final functional destinations within their RBC host cells. The secretory pathway also serves as a launch pad for proteins targeted to the non-photosynthetic apicoplast organelle of endosymbiotic origin, and the role of heat shock proteins in trafficking proteins here will be reviewed. Finally, the function of chaperones in protein trafficking into the mitochondrion, the remaining organelle of endosymbiotic origin, will be discussed.
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Affiliation(s)
- Thorey K Jonsdottir
- Burnet Institute, Melbourne, VIC, Australia.,Department of Microbiology and Immunology, University of Melbourne, Parkville, VIC, Australia
| | - Mikha Gabriela
- Burnet Institute, Melbourne, VIC, Australia.,School of Medicine, Deakin University, Waurn Ponds, VIC, Australia
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21
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PV1 Protein from Plasmodium falciparum Exhibits Chaperone-Like Functions and Cooperates with Hsp100s. Int J Mol Sci 2020; 21:ijms21228616. [PMID: 33207549 PMCID: PMC7697860 DOI: 10.3390/ijms21228616] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Revised: 11/09/2020] [Accepted: 11/10/2020] [Indexed: 01/17/2023] Open
Abstract
Plasmodium falciparum parasitophorous vacuolar protein 1 (PfPV1), a protein unique to malaria parasites, is localized in the parasitophorous vacuolar (PV) and is essential for parasite growth. Previous studies suggested that PfPV1 cooperates with the Plasmodium translocon of exported proteins (PTEX) complex to export various proteins from the PV. However, the structure and function of PfPV1 have not been determined in detail. In this study, we undertook the expression, purification, and characterization of PfPV1. The tetramer appears to be the structural unit of PfPV1. The activity of PfPV1 appears to be similar to that of molecular chaperones, and it may interact with various proteins. PfPV1 could substitute CtHsp40 in the CtHsp104, CtHsp70, and CtHsp40 protein disaggregation systems. Based on these results, we propose a model in which PfPV1 captures various PV proteins and delivers them to PTEX through a specific interaction with HSP101.
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22
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Live-Cell FRET Reveals that Malaria Nutrient Channel Proteins CLAG3 and RhopH2 Remain Associated throughout Their Tortuous Trafficking. mBio 2020; 11:mBio.01354-20. [PMID: 32900800 PMCID: PMC7482060 DOI: 10.1128/mbio.01354-20] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Malaria parasites increase their host erythrocyte's permeability to various nutrients, fueling intracellular pathogen development and replication. The plasmodial surface anion channel (PSAC) mediates this uptake and is linked to the parasite-encoded RhopH complex, consisting of CLAG3, RhopH2, and RhopH3. While interactions between these subunits are well established, it is not clear whether they remain associated from their synthesis in developing merozoites through erythrocyte invasion and trafficking to the host membrane. Here, we explored protein-protein interactions between RhopH subunits using live-cell imaging and Förster resonance energy transfer (FRET) experiments. Using the green fluorescent protein (GFP) derivatives mCerulean and mVenus, we generated single- and double-tagged parasite lines for fluorescence measurements. While CLAG3-mCerulean served as an efficient FRET donor for RhopH2-mVenus within rhoptry organelles, mCerulean targeted to this organelle via a short signal sequence produced negligible FRET. Upon merozoite egress and reinvasion, these tagged RhopH subunits were deposited into the new host cell's parasitophorous vacuole; these proteins were then exported and trafficked to the erythrocyte membrane, where CLAG3 and RhopH2 remained fully associated. Fluorescence intensity measurements identified stoichiometric increases in exported RhopH protein when erythrocytes are infected with two parasites; whole-cell patch-clamp revealed a concomitant increase in PSAC functional copy number and a dose effect for RhopH contribution to ion and nutrient permeability. These studies establish live-cell FRET imaging in human malaria parasites, reveal that RhopH subunits traffic to their host membrane destination without dissociation, and suggest quantitative contribution to PSAC formation.IMPORTANCE Malaria parasites grow within circulating red blood cells and uptake nutrients through a pore on their host membrane. Here, we used gene editing to tag CLAG3 and RhopH2, two proteins linked to the nutrient pore, with fluorescent markers and tracked these proteins in living infected cells. After their synthesis in mature parasites, imaging showed that both proteins are packaged into membrane-bound rhoptries. When parasites ruptured their host cells and invaded new red blood cells, these proteins were detected within a vacuole around the parasite before they migrated and inserted in the surface membrane of the host cell. Using simultaneous labeling of CLAG3 and RhopH2, we determined that these proteins interact tightly during migration and after surface membrane insertion. Red blood cells infected with two parasites had twice the protein at their surface and a parallel increase in the number of nutrient pores. Our work suggests that these proteins directly facilitate parasite nutrient uptake from human plasma.
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23
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Plastid biogenesis in malaria parasites requires the interactions and catalytic activity of the Clp proteolytic system. Proc Natl Acad Sci U S A 2020; 117:13719-13729. [PMID: 32482878 DOI: 10.1073/pnas.1919501117] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The human malaria parasite, Plasmodium falciparum, contains an essential plastid called the apicoplast. Most apicoplast proteins are encoded by the nuclear genome and it is unclear how the plastid proteome is regulated. Here, we study an apicoplast-localized caseinolytic-protease (Clp) system and how it regulates organelle proteostasis. Using null and conditional mutants, we demonstrate that the P. falciparum Clp protease (PfClpP) has robust enzymatic activity that is essential for apicoplast biogenesis. We developed a CRISPR/Cas9-based system to express catalytically dead PfClpP, which showed that PfClpP oligomerizes as a zymogen and is matured via transautocatalysis. The expression of both wild-type and mutant Clp chaperone (PfClpC) variants revealed a functional chaperone-protease interaction. Conditional mutants of the substrate-adaptor (PfClpS) demonstrated its essential function in plastid biogenesis. A combination of multiple affinity purification screens identified the Clp complex composition as well as putative Clp substrates. This comprehensive study reveals the molecular composition and interactions influencing the proteolytic function of the apicoplast Clp system and demonstrates its central role in the biogenesis of the plastid in malaria parasites.
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24
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Florentin A, Cobb DW, Kudyba HM, Muralidharan V. Directing traffic: Chaperone-mediated protein transport in malaria parasites. Cell Microbiol 2020; 22:e13215. [PMID: 32388921 PMCID: PMC7282954 DOI: 10.1111/cmi.13215] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 04/12/2020] [Accepted: 04/14/2020] [Indexed: 12/16/2022]
Abstract
The ability of eukaryotic parasites from the phylum Apicomplexa to cause devastating diseases is predicated upon their ability to maintain faithful and precise protein trafficking mechanisms. Their parasitic life cycle depends on the trafficking of effector proteins to the infected host cell, transport of proteins to several critical organelles required for survival, as well as transport of parasite and host proteins to the digestive organelles to generate the building blocks for parasite growth. Several recent studies have shed light on the molecular mechanisms parasites utilise to transform the infected host cells, transport proteins to essential metabolic organelles and for biogenesis of organelles required for continuation of their life cycle. Here, we review key pathways of protein transport originating and branching from the endoplasmic reticulum, focusing on the essential roles of chaperones in these processes. Further, we highlight key gaps in our knowledge that prevents us from building a holistic view of protein trafficking in these deadly human pathogens.
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Affiliation(s)
- Anat Florentin
- Department of Cellular Biology, University of Georgia, Athens, Georgia, USA.,Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
| | - David W Cobb
- Department of Cellular Biology, University of Georgia, Athens, Georgia, USA.,Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
| | - Heather M Kudyba
- Department of Cellular Biology, University of Georgia, Athens, Georgia, USA.,Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
| | - Vasant Muralidharan
- Department of Cellular Biology, University of Georgia, Athens, Georgia, USA.,Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
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25
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An Endoplasmic Reticulum CREC Family Protein Regulates the Egress Proteolytic Cascade in Malaria Parasites. mBio 2020; 11:mBio.03078-19. [PMID: 32098818 PMCID: PMC7042697 DOI: 10.1128/mbio.03078-19] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The endoplasmic reticulum (ER) is thought to play an essential role during egress of malaria parasites because the ER is assumed to be required for biogenesis and secretion of egress-related organelles. However, no proteins localized to the parasite ER have been shown to play a role in egress of malaria parasites. In this study, we generated conditional mutants of the Plasmodium falciparum endoplasmic reticulum-resident calcium-binding protein (PfERC), a member of the CREC family. Knockdown of the PfERC gene showed that this gene is essential for asexual growth of P. falciparum Analysis of the intraerythrocytic life cycle revealed that PfERC is essential for parasite egress but is not required for protein trafficking or calcium storage. We found that PfERC knockdown prevents the rupture of the parasitophorous vacuole membrane. This is because PfERC knockdown inhibited the proteolytic maturation of the subtilisin-like serine protease SUB1. Using double mutant parasites, we showed that PfERC is required for the proteolytic maturation of the essential aspartic protease plasmepsin X, which is required for SUB1 cleavage. Further, we showed that processing of substrates downstream of the proteolytic cascade is inhibited by PfERC knockdown. Thus, these data establish that the ER-resident CREC family protein PfERC is a key early regulator of the egress proteolytic cascade of malaria parasites.IMPORTANCE The divergent eukaryotic parasites that cause malaria grow and divide within a vacuole inside a host cell, which they have to break open once they finish cell division. The egress of daughter parasites requires the activation of a proteolytic cascade, and a subtilisin-like protease initiates a proteolytic cascade to break down the membranes blocking egress. It is assumed that the parasite endoplasmic reticulum plays a role in this process, but the proteins in this organelle required for egress remain unknown. We have identified an early ER-resident regulator essential for the maturation of the recently discovered aspartic protease in the egress proteolytic cascade, plasmepsin X, which is required for maturation of the subtilisin-like protease. Conditional loss of PfERC results in the formation of immature and inactive egress proteases that are unable to breakdown the vacuolar membrane barring release of daughter parasites.
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26
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Jankowska-Döllken M, Sanchez CP, Cyrklaff M, Lanzer M. Overexpression of the HECT ubiquitin ligase PfUT prolongs the intraerythrocytic cycle and reduces invasion efficiency of Plasmodium falciparum. Sci Rep 2019; 9:18333. [PMID: 31797898 PMCID: PMC6893019 DOI: 10.1038/s41598-019-54854-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Accepted: 11/18/2019] [Indexed: 11/22/2022] Open
Abstract
The glms ribozyme system has been used as an amenable tool to conditionally control expression of genes of interest. It is generally assumed that insertion of the ribozyme sequence does not affect expression of the targeted gene in the absence of the inducer glucosamine-6-phosphate, although experimental support for this assumption is scarce. Here, we report the unexpected finding that integration of the glms ribozyme sequence in the 3′ untranslated region of a gene encoding a HECT E3 ubiquitin ligase, termed Plasmodium falciparum ubiquitin transferase (PfUT), increased steady state RNA and protein levels 2.5-fold in the human malaria parasite P. falciparum. Overexpression of pfut resulted in an S/M phase-associated lengthening of the parasite’s intraerythrocytic developmental cycle and a reduced merozoite invasion efficiency. The addition of glucosamine partially restored the wild type phenotype. Our study suggests a role of PfUT in controlling cell cycle progression and merozoite invasion. Our study further raises awareness regarding unexpected effects on gene expression when inserting the glms ribozyme sequence into a gene locus.
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Affiliation(s)
- Monika Jankowska-Döllken
- Center of Infectious Diseases, Parasitology, Heidelberg University Hospital, Im Neuenheimer Feld 324, 69120, Heidelberg, Germany
| | - Cecilia P Sanchez
- Center of Infectious Diseases, Parasitology, Heidelberg University Hospital, Im Neuenheimer Feld 324, 69120, Heidelberg, Germany
| | - Marek Cyrklaff
- Center of Infectious Diseases, Parasitology, Heidelberg University Hospital, Im Neuenheimer Feld 324, 69120, Heidelberg, Germany
| | - Michael Lanzer
- Center of Infectious Diseases, Parasitology, Heidelberg University Hospital, Im Neuenheimer Feld 324, 69120, Heidelberg, Germany.
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27
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Day J, Passecker A, Beck HP, Vakonakis I. The Plasmodium falciparum Hsp70-x chaperone assists the heat stress response of the malaria parasite. FASEB J 2019; 33:14611-14624. [PMID: 31690116 PMCID: PMC6894070 DOI: 10.1096/fj.201901741r] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Accepted: 09/23/2019] [Indexed: 01/25/2023]
Abstract
Plasmodium falciparum is the most lethal of human-infective malaria parasites. A hallmark of P. falciparum malaria is extensive remodeling of host erythrocytes by the parasite, which facilitates the development of virulence properties such as host cell adhesion to the endothelial lining of the microvasculature. Host remodeling is mediated by a large complement of parasite proteins exported to the erythrocyte; among them is a single heat shock protein (Hsp)70-class protein chaperone, P. falciparum Hsp70-x (PfHsp70-x). PfHsp70-x was previously shown to assist the development of virulent cytoadherence characteristics. Here, we show that PfHsp70-x also supports parasite growth under elevated temperature conditions that simulate febrile episodes, especially at the beginning of the parasite life cycle when most of host cell remodeling takes place. Biochemical and biophysical analyses of PfHsp70-x, including crystallographic structures of its catalytic domain and the J-domain of its stimulatory Hsp40 cochaperone, suggest that PfHsp70-x is highly similar to human Hsp70 chaperones endogenous to the erythrocyte. Nevertheless, our results indicate that selective inhibition of PfHsp70-x function using small molecules may be possible and highlight specific sites of its catalytic domain as potentially of high interest. We discuss the likely roles of PfHsp70-x and human chaperones in P. falciparum biology and how specific inhibitors may assist us in disentangling their relative contributions.-Day, J., Passecker, A., Beck, H.-P., Vakonakis, I. The Plasmodium falciparum Hsp70-x chaperone assists the heat stress response of the malaria parasite.
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Affiliation(s)
- Jemma Day
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Armin Passecker
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Hans-Peter Beck
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Ioannis Vakonakis
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
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28
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Zininga T, Shonhai A. Small Molecule Inhibitors Targeting the Heat Shock Protein System of Human Obligate Protozoan Parasites. Int J Mol Sci 2019; 20:E5930. [PMID: 31775392 PMCID: PMC6929125 DOI: 10.3390/ijms20235930] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 10/29/2019] [Accepted: 11/13/2019] [Indexed: 12/13/2022] Open
Abstract
Obligate protozoan parasites of the kinetoplastids and apicomplexa infect human cells to complete their life cycles. Some of the members of these groups of parasites develop in at least two systems, the human host and the insect vector. Survival under the varied physiological conditions associated with the human host and in the arthropod vectors requires the parasites to modulate their metabolic complement in order to meet the prevailing conditions. One of the key features of these parasites essential for their survival and host infectivity is timely expression of various proteins. Even more importantly is the need to keep their proteome functional by maintaining its functional capabilities in the wake of physiological changes and host immune responses. For this reason, molecular chaperones (also called heat shock proteins)-whose role is to facilitate proteostasis-play an important role in the survival of these parasites. Heat shock protein 90 (Hsp90) and Hsp70 are prominent molecular chaperones that are generally induced in response to physiological stress. Both Hsp90 and Hsp70 members are functionally regulated by nucleotides. In addition, Hsp70 and Hsp90 cooperate to facilitate folding of some key proteins implicated in cellular development. In addition, Hsp90 and Hsp70 individually interact with other accessory proteins (co-chaperones) that regulate their functions. The dependency of these proteins on nucleotide for their chaperone function presents an Achille's heel, as inhibitors that mimic ATP are amongst potential therapeutic agents targeting their function in obligate intracellular human parasites. Most of the promising small molecule inhibitors of parasitic heat shock proteins are either antibiotics or anticancer agents, whose repurposing against parasitic infections holds prospects. Both cancer cells and obligate human parasites depend upon a robust protein quality control system to ensure their survival, and hence, both employ a competent heat shock machinery to this end. Furthermore, some inhibitors that target chaperone and co-chaperone networks also offer promising prospects as antiparasitic agents. The current review highlights the progress made so far in design and application of small molecule inhibitors against obligate intracellular human parasites of the kinetoplastida and apicomplexan kingdoms.
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Affiliation(s)
| | - Addmore Shonhai
- Department of Biochemistry, School of Mathematical and Natural Sciences, University of Venda, Thohoyandou 0950, South Africa;
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29
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Establishing Computational Approaches Towards Identifying Malarial Allosteric Modulators: A Case Study of Plasmodium falciparum Hsp70s. Int J Mol Sci 2019; 20:ijms20225574. [PMID: 31717270 PMCID: PMC6887781 DOI: 10.3390/ijms20225574] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 10/24/2019] [Accepted: 10/27/2019] [Indexed: 02/07/2023] Open
Abstract
Combating malaria is almost a never-ending battle, as Plasmodium parasites develop resistance to the drugs used against them, as observed recently in artemisinin-based combination therapies. The main concern now is if the resistant parasite strains spread from Southeast Asia to Africa, the continent hosting most malaria cases. To prevent catastrophic results, we need to find non-conventional approaches. Allosteric drug targeting sites and modulators might be a new hope for malarial treatments. Heat shock proteins (HSPs) are potential malarial drug targets and have complex allosteric control mechanisms. Yet, studies on designing allosteric modulators against them are limited. Here, we identified allosteric modulators (SANC190 and SANC651) against P. falciparum Hsp70-1 and Hsp70-x, affecting the conformational dynamics of the proteins, delicately balanced by the endogenous ligands. Previously, we established a pipeline to identify allosteric sites and modulators. This study also further investigated alternative approaches to speed up the process by comparing all atom molecular dynamics simulations and dynamic residue network analysis with the coarse-grained (CG) versions of the calculations. Betweenness centrality (BC) profiles for PfHsp70-1 and PfHsp70-x derived from CG simulations not only revealed similar trends but also pointed to the same functional regions and specific residues corresponding to BC profile peaks.
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30
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Lee MCS, Lindner SE, Lopez-Rubio JJ, Llinás M. Cutting back malaria: CRISPR/Cas9 genome editing of Plasmodium. Brief Funct Genomics 2019; 18:281-289. [PMID: 31365053 PMCID: PMC6859820 DOI: 10.1093/bfgp/elz012] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 04/15/2019] [Accepted: 05/20/2019] [Indexed: 12/15/2022] Open
Abstract
CRISPR/Cas9 approaches are revolutionizing our ability to perform functional genomics across a wide range of organisms, including the Plasmodium parasites that cause malaria. The ability to deliver single point mutations, epitope tags and gene deletions at increased speed and scale is enabling our understanding of the biology of these complex parasites, and pointing to potential new therapeutic targets. In this review, we describe some of the biological and technical considerations for designing CRISPR-based experiments, and discuss potential future developments that broaden the applications for CRISPR/Cas9 interrogation of the malaria parasite genome.
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Affiliation(s)
- Marcus C S Lee
- Parasites and Microbes Programme, Wellcome Sanger Institute, Hinxton, UK
| | - Scott E Lindner
- Department of Biochemistry and Molecular Biology, Huck Center for Malaria Research, The Pennsylvania State University, Pennsylvania, USA
| | - Jose-Juan Lopez-Rubio
- Dynamique des Interactions Membranaires Normales et Pathologiques, UMR5235 CNRS, INSERM, Université Montpellier, Montpellier, France
| | - Manuel Llinás
- Department of Biochemistry and Molecular Biology, Huck Center for Malaria Research, The Pennsylvania State University, Pennsylvania, USA
- Department of Chemistry, The Pennsylvania State University, Pennsylvania, USA
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31
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Daniyan MO, Przyborski JM, Shonhai A. Partners in Mischief: Functional Networks of Heat Shock Proteins of Plasmodium falciparum and Their Influence on Parasite Virulence. Biomolecules 2019; 9:E295. [PMID: 31340488 PMCID: PMC6681276 DOI: 10.3390/biom9070295] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 06/28/2019] [Accepted: 06/28/2019] [Indexed: 02/06/2023] Open
Abstract
The survival of the human malaria parasite Plasmodium falciparum under the physiologically distinct environments associated with their development in the cold-blooded invertebrate mosquito vectors and the warm-blooded vertebrate human host requires a genome that caters to adaptability. To this end, a robust stress response system coupled to an efficient protein quality control system are essential features of the parasite. Heat shock proteins constitute the main molecular chaperone system of the cell, accounting for approximately two percent of the malaria genome. Some heat shock proteins of parasites constitute a large part (5%) of the 'exportome' (parasite proteins that are exported to the infected host erythrocyte) that modify the host cell, promoting its cyto-adherence. In light of their importance in protein folding and refolding, and thus the survival of the parasite, heat shock proteins of P. falciparum have been a major subject of study. Emerging evidence points to their role not only being cyto-protection of the parasite, as they are also implicated in regulating parasite virulence. In undertaking their roles, heat shock proteins operate in networks that involve not only partners of parasite origin, but also potentially functionally associate with human proteins to facilitate parasite survival and pathogenicity. This review seeks to highlight these interplays and their roles in parasite pathogenicity. We further discuss the prospects of targeting the parasite heat shock protein network towards the developments of alternative antimalarial chemotherapies.
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Affiliation(s)
- Michael O Daniyan
- Department of Pharmacology, Faculty of Pharmacy, Obafemi Awolowo University, Ile-Ife, Osun State 220005, Nigeria.
| | - Jude M Przyborski
- Center of Infectious Diseases, Parasitology, University of Heidelberg Medical School, INF324, 69120 Heidelberg, Germany
| | - Addmore Shonhai
- Department of Biochemistry, School of Mathematical & Natural Sciences, University of Venda, P. Bag X5050, Thohoyandou 0950, South Africa.
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32
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Chakafana G, Zininga T, Shonhai A. Comparative structure-function features of Hsp70s of Plasmodium falciparum and human origins. Biophys Rev 2019; 11:591-602. [PMID: 31280465 PMCID: PMC6682331 DOI: 10.1007/s12551-019-00563-w] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 06/20/2019] [Indexed: 01/18/2023] Open
Abstract
The heat shock protein 70 (Hsp70) family of molecular chaperones are crucial for the survival and pathogenicity of the main agent of malaria, Plasmodium falciparum. Hsp70 is central to cellular proteostasis and some of its isoforms are essential for survival of the malaria parasite. In addition, they are also implicated in the development of antimalarial drug resistance. For these reasons, they are thought to be potential drug targets, especially in antimalarial combination therapies. However, their high sequence conservation across species presents a hurdle with respect to their selective targeting. The human genome encodes 17 Hsp70 isoforms while P. falciparum encodes for only 6. The structural architecture of Hsp70s is typically characterized by a highly conserved N-terminal nucleotide-binding domain (NBD) and a less conserved C-terminal substrate-binding domain (SBD). The two domains are connected by a highly conserved linker. In spite of their fairly high sequence conservation, Hsp70s from various species possess unique signature motifs that appear to uniquely influence their function. In addition, their cooperation with co-chaperones further regulates their functional specificity. In the current review, bioinformatics tools were used to identify conserved and unique signature motifs in Hsp70s of P. falciparum versus their human counterparts. We discuss the common and distinctive structure-function features of these proteins. This information is important towards elucidating the prospects of selective targeting of parasite heat shock proteins as part of antimalarial design efforts.
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Affiliation(s)
- Graham Chakafana
- Department of Biochemistry, University of Venda, Private Bags X5050, Thohoyandou, 0950, South Africa
| | - Tawanda Zininga
- Department of Biochemistry, University of Venda, Private Bags X5050, Thohoyandou, 0950, South Africa
| | - Addmore Shonhai
- Department of Biochemistry, University of Venda, Private Bags X5050, Thohoyandou, 0950, South Africa.
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33
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Kudyba HM, Cobb DW, Fierro MA, Florentin A, Ljolje D, Singh B, Lucchi NW, Muralidharan V. The endoplasmic reticulum chaperone PfGRP170 is essential for asexual development and is linked to stress response in malaria parasites. Cell Microbiol 2019; 21:e13042. [PMID: 31087747 PMCID: PMC6699899 DOI: 10.1111/cmi.13042] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 04/09/2019] [Accepted: 05/09/2019] [Indexed: 12/24/2022]
Abstract
The vast majority of malaria mortality is attributed to one parasite species: Plasmodium falciparum. Asexual replication of the parasite within the red blood cell is responsible for the pathology of the disease. In Plasmodium, the endoplasmic reticulum (ER) is a central hub for protein folding and trafficking as well as stress response pathways. In this study, we tested the role of an uncharacterised ER protein, PfGRP170, in regulating these key functions by generating conditional mutants. Our data show that PfGRP170 localises to the ER and is essential for asexual growth, specifically required for proper development of schizonts. PfGRP170 is essential for surviving heat shock, suggesting a critical role in cellular stress response. The data demonstrate that PfGRP170 interacts with the Plasmodium orthologue of the ER chaperone, BiP. Finally, we found that loss of PfGRP170 function leads to the activation of the Plasmodium eIF2α kinase, PK4, suggesting a specific role for this protein in this parasite stress response pathway.
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Affiliation(s)
- Heather M Kudyba
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia.,Department of Cellular Biology, University of Georgia, Athens, Georgia
| | - David W Cobb
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia.,Department of Cellular Biology, University of Georgia, Athens, Georgia
| | - Manuel A Fierro
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia.,Department of Cellular Biology, University of Georgia, Athens, Georgia
| | - Anat Florentin
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Dragan Ljolje
- Malaria Branch and Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Balwan Singh
- Malaria Branch and Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Naomi W Lucchi
- Malaria Branch and Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Vasant Muralidharan
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia.,Department of Cellular Biology, University of Georgia, Athens, Georgia
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34
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Matthews KM, Pitman EL, de Koning-Ward TF. Illuminating how malaria parasites export proteins into host erythrocytes. Cell Microbiol 2019; 21:e13009. [PMID: 30656810 DOI: 10.1111/cmi.13009] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 12/06/2018] [Accepted: 12/17/2018] [Indexed: 12/11/2022]
Abstract
Plasmodium parasites that cause the disease malaria have developed an elaborate trafficking pathway to facilitate the export of hundreds of effector proteins into their host cell, the erythrocyte. In this review, we outline how certain effector proteins contribute to parasite survival, virulence, and immune evasion. We also highlight how parasite proteins destined for export are recognised at the endoplasmic reticulum to facilitate entry into the export pathway and how the effector proteins are able to transverse the bounding parasitophorous vaculoar membrane via the Plasmodium translocon of exported proteins to gain access to the host cell. Some of the gaps in our understanding of the export pathway are also presented. Finally, we examine the degree of conservation of some of the key components of the Plasmodium export pathway in closely related apicomplexan parasites, which may provide insight into how the diverse apicomplexan parasites have adapted to survival pressures encountered within their respective host cells.
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Affiliation(s)
| | - Ethan L Pitman
- School of Medicine, Deakin University, Waurn Ponds, Victoria, Australia
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35
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Ng CL, Fidock DA. Plasmodium falciparum In Vitro Drug Resistance Selections and Gene Editing. Methods Mol Biol 2019; 2013:123-140. [PMID: 31267498 DOI: 10.1007/978-1-4939-9550-9_9] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Malaria continues to be a global health burden, threatening over 40% of the world's population. Drug resistance in Plasmodium falciparum, the etiological agent of the majority of human malaria cases, is compromising elimination efforts. New approaches to treating drug-resistant malaria benefit from defining resistance liabilities of known antimalarial agents and compounds in development and defining genetic changes that mediate loss of parasite susceptibility. Here, we present protocols for in vitro selection of drug-resistant parasites and for site-directed gene editing of candidate resistance mediators to test for causality.
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Affiliation(s)
- Caroline L Ng
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, USA
| | - David A Fidock
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA. .,Division of Infectious Diseases, Department of Medicine, Columbia University Irving Medical Center, New York, NY, USA.
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36
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Mabate B, Zininga T, Ramatsui L, Makumire S, Achilonu I, Dirr HW, Shonhai A. Structural and biochemical characterization of Plasmodium falciparum Hsp70-x reveals functional versatility of its C-terminal EEVN motif. Proteins 2018; 86:1189-1201. [PMID: 30183110 PMCID: PMC6282620 DOI: 10.1002/prot.25600] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 08/27/2018] [Accepted: 08/31/2018] [Indexed: 01/12/2023]
Abstract
Plasmodium falciparum, the main agent of malaria expresses six members of the heat shock protein 70 (Hsp70) family. Hsp70s serve as protein folding facilitators in the cell. Amongst the six Hsp70 species that P. falciparum expresses, Hsp70-x (PfHsp70-x), is partially exported to the host red blood cell where it is implicated in host cell remodeling. Nearly 500 proteins of parasitic origin are exported to the parasite-infected red blood cell (RBC) along with PfHsp70-x. The role of PfHsp70-x in the infected human RBC remains largely unclear. One of the defining features of PfHsp70-x is the presence of EEVN residues at its C-terminus. In this regard, PfHsp70-x resembles canonical eukaryotic cytosol-localized Hsp70s which possess EEVD residues at their C-termini in place of the EEVN residues associated with PfHsp70-x. The EEVD residues of eukaryotic Hsp70s facilitate their interaction with co-chaperones. Characterization of the role of the EEVN residues of PfHsp70-x could provide insights into the function of this protein. In the current study, we expressed and purified recombinant PfHsp70-x (full length) and its EEVN minus form (PfHsp70-xT ). We then conducted structure- function assays towards establishing the role of the EEVN motif of PfHsp70-x. Our findings suggest that the EEVN residues of PfHsp70-x are important for its ATPase activity and chaperone function. Furthermore, the EEVN residues are crucial for the direct interaction between PfHsp70-x and human Hsp70-Hsp90 organizing protein (hHop) in vitro. Hop facilitates functional cooperation between Hsp70 and Hsp90. However, it remains to be established if PfHsp70-x and hHsp90 cooperate in vivo.
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Affiliation(s)
| | | | | | | | - Ikechukwu Achilonu
- Protein Structure‐Function Research UnitSchool of Molecular & Cell Biology, University of the WitwatersrandJohannesburgSouth Africa
| | - Heini W. Dirr
- Protein Structure‐Function Research UnitSchool of Molecular & Cell Biology, University of the WitwatersrandJohannesburgSouth Africa
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37
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Kudyba HM, Cobb DW, Florentin A, Krakowiak M, Muralidharan V. CRISPR/Cas9 Gene Editing to Make Conditional Mutants of Human Malaria Parasite P. falciparum. J Vis Exp 2018. [PMID: 30295650 DOI: 10.3791/57747] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Malaria is a significant cause of morbidity and mortality worldwide. This disease, which primarily affects those living in tropical and subtropical regions, is caused by infection with Plasmodium parasites. The development of more effective drugs to combat malaria can be accelerated by improving our understanding of the biology of this complex parasite. Genetic manipulation of these parasites is key to understanding their biology; however, historically the genome of P. falciparum has been difficult to manipulate. Recently, CRISPR/Cas9 genome editing has been utilized in malaria parasites, allowing for easier protein tagging, generation of conditional protein knockdowns, and deletion of genes. CRISPR/Cas9 genome editing has proven to be a powerful tool for advancing the field of malaria research. Here, we describe a CRISPR/Cas9 method for generating glmS-based conditional knockdown mutants in P. falciparum. This method is highly adaptable to other types of genetic manipulations, including protein tagging and gene knockouts.
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Affiliation(s)
- Heather M Kudyba
- Department of Cellular Biology, University of Georgia; Center for Tropical and Emerging Global Diseases, University of Georgia
| | - David W Cobb
- Department of Cellular Biology, University of Georgia
| | - Anat Florentin
- Department of Cellular Biology, University of Georgia; Center for Tropical and Emerging Global Diseases, University of Georgia
| | | | - Vasant Muralidharan
- Department of Cellular Biology, University of Georgia; Center for Tropical and Emerging Global Diseases, University of Georgia;
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38
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Florentin A, Cobb DW, Fishburn JD, Cipriano MJ, Kim PS, Fierro MA, Striepen B, Muralidharan V. PfClpC Is an Essential Clp Chaperone Required for Plastid Integrity and Clp Protease Stability in Plasmodium falciparum. Cell Rep 2017; 21:1746-1756. [PMID: 29141210 PMCID: PMC5726808 DOI: 10.1016/j.celrep.2017.10.081] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 08/17/2017] [Accepted: 10/21/2017] [Indexed: 01/11/2023] Open
Abstract
The deadly malaria parasite Plasmodium falciparum contains a nonphotosynthetic plastid, known as the apicoplast, that functions to produce essential metabolites, and drugs that target the apicoplast are clinically effective. Several prokaryotic caseinolytic protease (Clp) genes have been identified in the Plasmodium genome. Using phylogenetic analysis, we focused on the Clp members that may form a regulated proteolytic complex in the apicoplast. We genetically targeted members of this complex and generated conditional mutants of the apicoplast-localized PfClpC chaperone and PfClpP protease. Conditional inhibition of the PfClpC chaperone resulted in growth arrest and apicoplast loss and was rescued by addition of the essential apicoplast-derived metabolite IPP. Using a double-conditional mutant parasite line, we discovered that the chaperone activity is required to stabilize the mature protease, revealing functional interactions. These data demonstrate the essential function of PfClpC in maintaining apicoplast integrity and its role in regulating the proteolytic activity of the Clp complex.
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Affiliation(s)
- Anat Florentin
- Department of Cellular Biology, University of Georgia, Athens, GA 30602, USA; Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA
| | - David W Cobb
- Department of Cellular Biology, University of Georgia, Athens, GA 30602, USA
| | - Jillian D Fishburn
- Department of Cellular Biology, University of Georgia, Athens, GA 30602, USA
| | - Michael J Cipriano
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA
| | - Paul S Kim
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA
| | - Manuel A Fierro
- Department of Cellular Biology, University of Georgia, Athens, GA 30602, USA
| | - Boris Striepen
- Department of Cellular Biology, University of Georgia, Athens, GA 30602, USA; Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA
| | - Vasant Muralidharan
- Department of Cellular Biology, University of Georgia, Athens, GA 30602, USA; Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA.
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