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Bekić V, Kilian N. Novel secretory organelles of parasite origin - at the center of host-parasite interaction. Bioessays 2023; 45:e2200241. [PMID: 37518819 DOI: 10.1002/bies.202200241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2022] [Revised: 06/26/2023] [Accepted: 06/28/2023] [Indexed: 08/01/2023]
Abstract
Reorganization of cell organelle-deprived host red blood cells by the apicomplexan malaria parasite Plasmodium falciparum enables their cytoadherence to endothelial cells that line the microvasculature. This increases the time red blood cells infected with mature developmental stages remain within selected organs such as the brain to avoid the spleen passage, which can lead to severe complications and cumulate in patient death. The Maurer's clefts are a novel secretory organelle of parasite origin established by the parasite in the cytoplasm of the host red blood cell in order to facilitate the establishment of cytoadherence by conducting the trafficking of immunovariant adhesins to the host cell surface. Another important function of the organelle is the sorting of other proteins the parasite traffics into its host cell. Although the organelle is of high importance for the pathology of malaria, additional putative functions, structure, and genesis remain shrouded in mystery more than a century after its discovery. In this review, we highlight our current knowledge about the Maurer's clefts and other novel secretory organelles established within the host cell cytoplasm by human-pathogenic malaria parasites and other parasites that reside within human red blood cells.
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Affiliation(s)
- Viktor Bekić
- School of Medicine, University of Zagreb, Zagreb, Croatia
| | - Nicole Kilian
- Centre for Infectious Diseases, Parasitology, Heidelberg University Hospital, Heidelberg, Germany
- Department of Medical Biochemistry, Faculty of Basic Medical Sciences, Delta State University, Abraka, Nigeria
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2
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Wiser MF. Knobs, Adhesion, and Severe Falciparum Malaria. Trop Med Infect Dis 2023; 8:353. [PMID: 37505649 PMCID: PMC10385726 DOI: 10.3390/tropicalmed8070353] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 06/30/2023] [Accepted: 07/02/2023] [Indexed: 07/29/2023] Open
Abstract
Plasmodium falciparum can cause a severe disease with high mortality. A major factor contributing to the increased virulence of P. falciparum, as compared to other human malarial parasites, is the sequestration of infected erythrocytes in the capillary beds of organs and tissues. This sequestration is due to the cytoadherence of infected erythrocytes to endothelial cells. Cytoadherence is primarily mediated by a parasite protein expressed on the surface of the infected erythrocyte called P. falciparum erythrocyte membrane protein-1 (PfEMP1). PfEMP1 is embedded in electron-dense protuberances on the surface of the infected erythrocytes called knobs. These knobs are assembled on the erythrocyte membrane via exported parasite proteins, and the knobs function as focal points for the cytoadherence of infected erythrocytes to endothelial cells. PfEMP1 is a member of the var gene family, and there are approximately 60 antigenically distinct PfEMP1 alleles per parasite genome. Var gene expression exhibits allelic exclusion, with only a single allele being expressed by an individual parasite. This results in sequential waves of antigenically distinct infected erythrocytes and this antigenic variation allows the parasite to establish long-term chronic infections. A wide range of endothelial cell receptors can bind to the various PfEMP1 alleles, and thus, antigenic variation also results in a change in the cytoadherence phenotype. The cytoadherence phenotype may result in infected erythrocytes sequestering in different tissues and this difference in sequestration may explain the wide range of possible clinical manifestations associated with severe falciparum malaria.
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Affiliation(s)
- Mark F Wiser
- Department of Tropical Medicine and Infectious Disease, Tulane University School of Public Health and Tropical Medicine, 1440 Canal Street, New Orleans, LA 70112, USA
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3
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Almaazmi SY, Kaur RP, Singh H, Blatch GL. The Plasmodium falciparum exported J domain proteins fine-tune human and malarial Hsp70s: pathological exploitation of proteostasis machinery. Front Mol Biosci 2023; 10:1216192. [PMID: 37457831 PMCID: PMC10349383 DOI: 10.3389/fmolb.2023.1216192] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Accepted: 06/12/2023] [Indexed: 07/18/2023] Open
Abstract
Cellular proteostasis requires a network of molecular chaperones and co-chaperones, which facilitate the correct folding and assembly of other proteins, or the degradation of proteins misfolded beyond repair. The function of the major chaperones, heat shock protein 70 (Hsp70) and heat shock protein 90 (Hsp90), is regulated by a cohort of co-chaperone proteins. The J domain protein (JDP) family is one of the most diverse co-chaperone families, playing an important role in functionalizing the Hsp70 chaperone system to form a powerful protein quality control network. The intracellular malaria parasite, Plasmodium falciparum, has evolved the capacity to invade and reboot mature human erythrocytes, turning them into a vehicles of pathology. This process appears to involve the harnessing of both the human and parasite chaperone machineries. It is well known that malaria parasite-infected erythrocytes are highly enriched in functional human Hsp70 (HsHsp70) and Hsp90 (HsHsp90), while recent proteomics studies have provided evidence that human JDPs (HsJDPs) may also be enriched, but at lower levels. Interestingly, P. falciparum JDPs (PfJDPs) are the most prominent and diverse family of proteins exported into the infected erythrocyte cytosol. We hypothesize that the exported PfJPDs may be an evolutionary consequence of the need to boost chaperone power for specific protein folding pathways that enable both survival and pathogenesis of the malaria parasite. The evidence suggests that there is an intricate network of PfJDP interactions with the exported malarial Hsp70 (PfHsp70-x) and HsHsp70, which appear to be important for the trafficking of key malarial virulence factors, and the proteostasis of protein complexes of human and parasite proteins associated with pathology. This review will critically evaluate the current understanding of the role of exported PfJDPs in pathological exploitation of the proteostasis machinery by fine-tuning the chaperone properties of both human and malarial Hsp70s.
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Affiliation(s)
- Shaikha Y. Almaazmi
- Biomedical Research and Drug Discovery Research Group, Faculty of Health Sciences, Higher Colleges of Technology, Sharjah, United Arab Emirates
| | - Rupinder P. Kaur
- The Department of Chemistry, Guru Nanak Dev University College Verka, Amritsar, Punjab, India
| | - Harpreet Singh
- Department of Bioinformatics, Hans Raj Mahila Maha Vidyalaya, Jalandhar, Punjab, India
| | - Gregory L. Blatch
- Biomedical Research and Drug Discovery Research Group, 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
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4
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Shakya B, Kilili GK, Wang L, Nakayasu ES, LaCount DJ. Identification of Exported Plasmodium falciparum Proteins That Bind to the Erythrocyte Cytoskeleton. Microorganisms 2022; 10:1438. [PMID: 35889157 PMCID: PMC9320996 DOI: 10.3390/microorganisms10071438] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 07/11/2022] [Accepted: 07/13/2022] [Indexed: 11/28/2022] Open
Abstract
Plasmodium proteins are exported to the erythrocyte cytoplasm to create an environment that supports parasite replication. Although hundreds of proteins are predicted to be exported through Plasmodium export element (PEXEL)-dependent and -independent mechanisms, the functions of exported proteins are largely uncharacterized. In this study, we used a biochemical screening approach to identify putative exported P. falciparum proteins that bound to inside-out vesicles prepared from erythrocytes. Out of 69 P. falciparum PEXEL-motif proteins tested, 18 bound to inside-out vesicles (IOVs) in two or more independent assays. Using co-affinity purifications followed by mass spectrometry, pairwise co-purification experiments, and the split-luciferase assay, we identified 31 putative protein-protein interactions between erythrocyte cytoskeletal proteins and predicted exported P. falciparum proteins. We further showed that PF3D7_1401600 binds to the spectrin-binding domain of erythrocyte ankyrin via its MESA erythrocyte cytoskeleton binding (MEC) motif and to the N-terminal domains of ankyrin and 4.1R through a fragment that required an intact Plasmodium helical interspersed sub-telomeric (PHIST) domain. Introduction of PF3D7_1401600 into erythrocyte ghosts increased retention in the microsphiltration assay, consistent with previous data that reported a reduction of rigidity in red blood cells infected with PF3D7_1401600-deficient parasites.
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Affiliation(s)
- Bikash Shakya
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907, USA; (B.S.); (G.K.K.); (L.W.)
| | - Geoffrey Kimiti Kilili
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907, USA; (B.S.); (G.K.K.); (L.W.)
| | - Ling Wang
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907, USA; (B.S.); (G.K.K.); (L.W.)
| | - Ernesto S. Nakayasu
- Bindley Bioscience Center, Purdue University, West Lafayette, IN 47907, USA;
- Pacific Northwest National Laboratory, Biological Sciences Division, Richland, WA 99352, USA
| | - Douglas J. LaCount
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907, USA; (B.S.); (G.K.K.); (L.W.)
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5
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Artemisinin resistance in the malaria parasite, Plasmodium falciparum, originates from its initial transcriptional response. Commun Biol 2022; 5:274. [PMID: 35347215 PMCID: PMC8960834 DOI: 10.1038/s42003-022-03215-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 02/16/2022] [Indexed: 12/30/2022] Open
Abstract
The emergence and spread of artemisinin-resistant Plasmodium falciparum, first in the Greater Mekong Subregion (GMS), and now in East Africa, is a major threat to global malaria elimination ambitions. To investigate the artemisinin resistance mechanism, transcriptome analysis was conducted of 577 P. falciparum isolates collected in the GMS between 2016–2018. A specific artemisinin resistance-associated transcriptional profile was identified that involves a broad but discrete set of biological functions related to proteotoxic stress, host cytoplasm remodelling, and REDOX metabolism. The artemisinin resistance-associated transcriptional profile evolved from initial transcriptional responses of susceptible parasites to artemisinin. The genetic basis for this adapted response is likely to be complex. Transcriptomic analysis of isolates from the malaria parasite (Plasmodium falciparum) in the Greater Mekong Subregion of Southeast Asia identifies gene expression patterns that are correlated with resistance to a common anti-malaria drug, artemisinin.
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Prata IO, Cubillos EFG, Krüger A, Barbosa D, Martins J, Setubal JC, Wunderlich G. Plasmodium falciparum Acetyl-CoA Synthetase Is Essential for Parasite Intraerythrocytic Development and Chromatin Modification. ACS Infect Dis 2021; 7:3224-3240. [PMID: 34766750 DOI: 10.1021/acsinfecdis.1c00414] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The malaria parasite Plasmodium falciparum possesses a unique Acetyl-CoA Synthetase (PfACS), which provides acetyl moieties for different metabolic and regulatory cellular pathways. We characterized PfACS and studied its role focusing on epigenetic modifications using the var gene family as reporter genes. For this, mutant lines to modulate plasmodial ACS expression by degron-mediated protein degradation and ribozyme-induced transcript decay were created. Additionally, an inhibitor of the human Acetyl-CoA Synthetase 2 was tested for its effectiveness in interfering with PfACS. The knockdown of PfACS or its inhibition resulted in impaired parasite growth. Decreased levels of PfACS also led to differential histone acetylation patterns, altered variant gene expression, and concomitantly decreased cytoadherence of infected red blood cells containing knocked-down parasites. Further, ChIP analysis revealed the presence of PfACS in many loci in ring stage parasites, underscoring its involvement in the regulation of chromatin. Due to its central function in the plasmodial metabolism and significant differences to human ACS, PfACS is an interesting target for drug development.
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Affiliation(s)
- Isadora Oliveira Prata
- Department of Parasitology, Institute for Biomedical Sciences, University of São Paulo, Avenida Professor Lineu Prestes 1374, 05508-000 São Paulo-SP, Brazil
| | - Eliana Fernanda Galindo Cubillos
- Department of Parasitology, Institute for Biomedical Sciences, University of São Paulo, Avenida Professor Lineu Prestes 1374, 05508-000 São Paulo-SP, Brazil
| | - Arne Krüger
- Department of Parasitology, Institute for Biomedical Sciences, University of São Paulo, Avenida Professor Lineu Prestes 1374, 05508-000 São Paulo-SP, Brazil
| | - Deibs Barbosa
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, Avenida Professor Lineu Prestes 748, 05508-000 São Paulo-SP, Brazil
| | - Joaquim Martins
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, Avenida Professor Lineu Prestes 748, 05508-000 São Paulo-SP, Brazil
| | - João Carlos Setubal
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, Avenida Professor Lineu Prestes 748, 05508-000 São Paulo-SP, Brazil
| | - Gerhard Wunderlich
- Department of Parasitology, Institute for Biomedical Sciences, University of São Paulo, Avenida Professor Lineu Prestes 1374, 05508-000 São Paulo-SP, Brazil
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7
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Keitany GJ, Jenkins BJ, Obiakor HT, Daniel S, Muehlenbachs A, Semblat JP, Gamain B, Doritchamou JYA, Desai SA, MacDonald NJ, Narum DL, Morrison R, Saveria T, Vignali M, Oleinikov AV, Fried M, Duffy PE. An invariant protein that co-localizes with VAR2CSA on Plasmodium falciparum-infected red cells binds to chondroitin sulfate A. J Infect Dis 2021; 225:2011-2022. [PMID: 34718641 DOI: 10.1093/infdis/jiab550] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 10/25/2021] [Indexed: 11/14/2022] Open
Abstract
Plasmodium falciparum-infected red blood cells (iRBCs) bind and sequester in deep vascular beds, causing malaria-related disease and death. In pregnant women, VAR2CSA binds to chondroitin sulfate A (CSA) and mediates placental sequestration, making it the major placental malaria (PM) vaccine target. Here, we characterize an invariant protein associated with PM called Plasmodium falciparum chondroitin sulfate A ligand (PfCSA-L). Recombinant PfCSA-L binds both placental CSA and VAR2CSA with nanomolar affinity, and is coexpressed on the iRBC surface with VAR2CSA. Unlike VAR2CSA, which is anchored by a transmembrane domain, PfCSA-L is peripherally associated with the outer surface of knobs through high affinity protein-protein interactions with VAR2CSA. This suggests iRBC sequestration involves complexes of invariant and variant surface proteins, allowing parasites to maintain both diversity and function at the iRBC surface. PfCSA-L is a promising target for intervention because it is well conserved, exposed on infected cells, and expressed and localized with VAR2CSA.
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Affiliation(s)
- Gladys J Keitany
- Center for Infectious Disease Research, Seattle, WA, USA.,University of Washington, Department of Pathobiology, Seattle, WA, USA
| | - Bethany J Jenkins
- Laboratory of Malaria Immunology and Vaccinology, NIAID, NIH, Bethesda, MD, USA
| | - Harold T Obiakor
- Laboratory of Malaria Immunology and Vaccinology, NIAID, NIH, Bethesda, MD, USA
| | - Shaji Daniel
- Laboratory of Malaria Immunology and Vaccinology, NIAID, NIH, Bethesda, MD, USA
| | - Atis Muehlenbachs
- University of Washington Medical Center, Anatomic Pathology, Seattle, WA, USA
| | - Jean-Philippe Semblat
- Université de Paris, Biologie Intégrée du Globule Rouge, UMR_S1134, Inserm, F-75015, Paris, France
| | - Benoit Gamain
- Université de Paris, Biologie Intégrée du Globule Rouge, UMR_S1134, Inserm, F-75015, Paris, France
| | | | - Sanjay A Desai
- Laboratory of Malaria and Vector Research, NIAID, NIH, Rockville, MD
| | | | - David L Narum
- Laboratory of Malaria Immunology and Vaccinology, NIAID, NIH, Bethesda, MD, USA
| | | | - Tracy Saveria
- Center for Infectious Disease Research, Seattle, WA, USA
| | | | | | - Michal Fried
- Center for Infectious Disease Research, Seattle, WA, USA.,University of Washington, Department of Pathobiology, Seattle, WA, USA.,Laboratory of Malaria Immunology and Vaccinology, NIAID, NIH, Bethesda, MD, USA
| | - Patrick E Duffy
- Center for Infectious Disease Research, Seattle, WA, USA.,University of Washington, Department of Pathobiology, Seattle, WA, USA.,Laboratory of Malaria Immunology and Vaccinology, NIAID, NIH, Bethesda, MD, USA
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8
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Isebe TI, Bargul JL, Gichuki BM, Njunge JM, Tuju J, Rono MK. Molecular characterization of Plasmodium falciparum PHISTb proteins as potential targets of naturally-acquired immunity against malaria. Wellcome Open Res 2021. [DOI: 10.12688/wellcomeopenres.15919.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Background: Plasmodium falciparum causes the deadliest form of malaria in humans. Upon infection, the host’s infected red blood cells (iRBCs) are remodelled by exported parasite proteins to provide a niche for parasite development and maturation. Methods: Here we analysed the role of three PHISTb proteins Pf3D7_0532400, Pf3D7_1401600, and Pf3D7_1102500 by expressing recombinant proteins and evaluated antibody responses against these proteins using immune sera from malaria-exposed individuals from Kenya and The Gambia in Africa. Results: Children and adults from malaria-endemic regions recognized the three PHISTb proteins. Responses against PHISTb proteins varied with malaria transmission intensity in three different geographical sites in Kenya (Siaya and Takaungu) and The Gambia (Sukuta). Antibody responses against PHISTb antigens Pf3D7_1102500 and Pf3D7_1401600 were higher in Sukuta, a low transmission region in Gambia, compared to Siaya, a high transmission region in western Kenya, unlike Pf3D7_0532400. Anti-PHIST responses indicate negative correlation between antibody levels and malaria transmission intensity for Pf3D7_1102500 and Pf3D7_1401600. We report a correlation in antibody responses between schizont and gametocyte extract, but this is not statistically significant (cor=0.102, p=0.2851, CI=95%) and, Pf3D7_0532400 (cor=0.11, p=0.249, CI=95%) and Pf3D7_1401600 (cor=0.02, p=0.7968, CI=95%). We report a negative correlation in antibody responses between schizont and Pf3D7_1102500 (cor=-0.008, p=0.9348, CI=95%). There is a correlation between gametocyte extract and Pf3D7_1401600 (cor=-0.0402, p=0.6735, CI=95%), Pf3D7_1102500 (cor=0.0758, p=0.4271, CI=95%) and Pf3D7_0532400 (cor=0.155, p=0.1028, CI=95%). Acquisition of anti-PHIST antibodies correlates with exposure to malaria for Pf3D7_0532400 (p=0.009) but not Pf3D7_1102500 and Pf3D7_1401600 (p=0.507 and p=0.15, respectively, CI=95%). Children aged below 2 years had the lowest antibody levels which do not correlate with age differences. Conclusions: Collectively, these findings provide evidence of natural immunity against PHISTb antigens that varies with level of malaria exposure and underscore their potential as possible serological markers to P. falciparum infection aimed at contributing to malaria control through vaccine development.
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9
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Yang B, Wang X, Jiang N, Sang X, Feng Y, Chen R, Wang X, Chen Q. Interaction Analysis of a Plasmodium falciparum PHISTa-like Protein and PfEMP1 Proteins. Front Microbiol 2020; 11:611190. [PMID: 33281807 PMCID: PMC7691434 DOI: 10.3389/fmicb.2020.611190] [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: 09/28/2020] [Accepted: 10/26/2020] [Indexed: 11/13/2022] Open
Abstract
Plasmodium falciparum extensively remodels host cells by translocating numerous proteins into the cytoplasm of red blood cells (RBCs) after invasion. Among these exported proteins, members of the Plasmodium helical interspersed subtelomeric (PHIST) family are crucial for host cell remodeling and host-parasite interactions, and thereby contribute to malaria pathogenesis. Herein, we explored the function of PF3D7_1372300, a member of the PHIST/PHISTa-like subfamily. PF3D7_1372300 was highly transcribed and expressed during the blood stage of P. falciparum, and distributed throughout RBCs, but most abundant at the erythrocyte membrane. Specific interaction of PF3D7_1372300 with the cytoplasmic tail of P. falciparum erythrocyte membrane protein 1 (PfEMP1) was revealed by immunofluorescence assay, in vitro intermolecular interaction assays. The interaction sites of PF3D7_1372300 with PfEMP1 ATS domain were found involved more than 30 amino acids (aa) at several positions. The findings deepen our understanding of host-parasite interactions and malaria pathogenesis.
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Affiliation(s)
- Baoling Yang
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, Shenyang Agricultural University, Shenyang, China.,College of Food Science and Technology, Shenyang Agricultural University, Shenyang, China.,The Research Unit for Pathogenic Mechanisms of Zoonotic Parasites, Chinese Academy of Medical Sciences, Shenyang, China
| | - Xiaofeng Wang
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences (CAS), University of Chinese Academy of Sciences, Beijing, China
| | - Ning Jiang
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, Shenyang Agricultural University, Shenyang, China.,The Research Unit for Pathogenic Mechanisms of Zoonotic Parasites, Chinese Academy of Medical Sciences, Shenyang, China
| | - Xiaoyu Sang
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, Shenyang Agricultural University, Shenyang, China.,The Research Unit for Pathogenic Mechanisms of Zoonotic Parasites, Chinese Academy of Medical Sciences, Shenyang, China
| | - Ying Feng
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, Shenyang Agricultural University, Shenyang, China.,The Research Unit for Pathogenic Mechanisms of Zoonotic Parasites, Chinese Academy of Medical Sciences, Shenyang, China
| | - Ran Chen
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, Shenyang Agricultural University, Shenyang, China.,The Research Unit for Pathogenic Mechanisms of Zoonotic Parasites, Chinese Academy of Medical Sciences, Shenyang, China
| | - Xinyi Wang
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, Shenyang Agricultural University, Shenyang, China.,College of Basic Sciences, Shenyang Agricultural University, Shenyang, China
| | - Qijun Chen
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, Shenyang Agricultural University, Shenyang, China.,The Research Unit for Pathogenic Mechanisms of Zoonotic Parasites, Chinese Academy of Medical Sciences, Shenyang, China
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10
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Mutisya JM, Mobegi VA, Kinyua JK, Kivecu MN, Okoth RO, Chemwor GC, Mwakio EW, Cheruiyot AC, Yeda RA, Okello CO, Juma JA, Opot BH, Juma DW, Roth AL, Akala HM, Andagalu BM. Characterization of sulfated polysaccharide activity against virulent Plasmodium falciparum PHISTb/RLP1 protein. F1000Res 2020; 9:1268. [PMID: 35600144 PMCID: PMC9096147 DOI: 10.12688/f1000research.26756.2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/19/2022] [Indexed: 11/20/2022] Open
Abstract
Background: The emergence of artemisinin resistance in South East Asia calls for urgent discovery of new drug compounds that have antiplasmodial activity. Unlike the classical compound screening drug discovery methods, the rational approach involving targeted drug discovery is less cumbersome and therefore key for innovation of new antiplasmodial compounds. Plasmodium falciparum (Pf) utilizes the process of host erythrocyte remodeling using Plasmodium-helical interspersed sub-telomeric domain (PHIST) containing proteins, which are amenable drug targets. The aim of this study is to identify inhibitors of PHIST from sulfated polysaccharides as new antimalarials. Methods: 251 samples from an ongoing study of epidemiology of malaria and drug resistance sensitivity patterns in Kenya were sequenced for PHISTb/RLP1 gene using Sanger sequencing. The sequenced reads were mapped to the reference Pf3D7 protein sequence of PHISTb/RLP1 using CLC Main Workbench. Homology modeling of both reference and mutant protein structures was achieved using the LOMETs tool. The models were refined using ModRefiner for energy minimization. Ramachandran plot was generated by ProCheck to assess the conformation of amino acids in the protein model. Protein binding sites predictions were assessed using FT SITE software. We searched for prospective antimalarials from PubChem. Docking experiments were achieved using AutoDock Vina and analysis results visualized in PyMOL. Results: Sanger sequencing generated 86 complete sequences. Upon mapping of the sequences to the reference, 12 non-synonymous single nucleotide polymorphisms were considered for mutant protein structure analysis. Eleven drug compounds with antiplasmodial activity were identified. Both modeled PHISTb/RLP1 reference and mutant structures had a Ramachandran score of >90% of the amino acids in the favored region. Ten of the drug compounds interacted with amino acid residues in PHISTb and RESA domains, showing potential activity against these proteins. Conclusion: This research identifies inhibitors of exported proteins that can be used in in vitro tests against the Plasmodium parasite.
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Affiliation(s)
- Jennifer M. Mutisya
- Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/Walter Reed Project, Kisumu, Kenya
- Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
| | - Victor A. Mobegi
- Department of Biochemistry, University of Nairobi, Nairobi, Kenya
| | - Johnson K. Kinyua
- Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
| | - Martha N. Kivecu
- Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/Walter Reed Project, Kisumu, Kenya
| | - Raphael O. Okoth
- Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/Walter Reed Project, Kisumu, Kenya
| | - Gladys C. Chemwor
- Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/Walter Reed Project, Kisumu, Kenya
| | - Edwin W. Mwakio
- Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/Walter Reed Project, Kisumu, Kenya
| | - Agnes C. Cheruiyot
- Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/Walter Reed Project, Kisumu, Kenya
| | - Redempta A. Yeda
- Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/Walter Reed Project, Kisumu, Kenya
| | - Charles O. Okello
- Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/Walter Reed Project, Kisumu, Kenya
| | - Jackline A. Juma
- Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/Walter Reed Project, Kisumu, Kenya
| | - Benjamin H. Opot
- Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/Walter Reed Project, Kisumu, Kenya
| | - Dennis W. Juma
- Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/Walter Reed Project, Kisumu, Kenya
| | - Amanda L. Roth
- Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/Walter Reed Project, Kisumu, Kenya
| | - Hosea M. Akala
- Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/Walter Reed Project, Kisumu, Kenya
| | - Ben M. Andagalu
- Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/Walter Reed Project, Kisumu, Kenya
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11
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Neveu G, Lavazec C. Erythrocyte Membrane Makeover by Plasmodium falciparum Gametocytes. Front Microbiol 2019; 10:2652. [PMID: 31787966 PMCID: PMC6856072 DOI: 10.3389/fmicb.2019.02652] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 10/30/2019] [Indexed: 12/17/2022] Open
Abstract
Plasmodium falciparum sexual parasites, called gametocytes, are the only parasite stages responsible for transmission from humans to Anopheles mosquitoes. During their maturation, P. falciparum gametocytes remodel the structural and mechanical properties of the membrane of their erythrocyte host. This remodeling is induced by the export of several parasite proteins and a dynamic reorganization of the erythrocyte cytoskeleton. Some of these modifications are specific for sexual stages and play a key role for gametocyte maturation, sequestration in internal organs, subsequent release in the bloodstream and ability to persist in circulation. Here we discuss the mechanisms developed by gametocytes to remodel their host cell and the functional relevance of these modifications.
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Affiliation(s)
- Gaëlle Neveu
- Inserm U1016, CNRS UMR 8104, Université de Paris, Institut Cochin, Paris, France.,Laboratoire d'Excellence GR-Ex, Paris, France
| | - Catherine Lavazec
- Inserm U1016, CNRS UMR 8104, Université de Paris, Institut Cochin, Paris, France.,Laboratoire d'Excellence GR-Ex, Paris, France
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12
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Host Cytoskeleton Remodeling throughout the Blood Stages of Plasmodium falciparum. Microbiol Mol Biol Rev 2019; 83:83/4/e00013-19. [PMID: 31484690 DOI: 10.1128/mmbr.00013-19] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The asexual intraerythrocytic development of Plasmodium falciparum, causing the most severe form of human malaria, is marked by extensive host cell remodeling. Throughout the processes of invasion, intracellular development, and egress, the erythrocyte membrane skeleton is remodeled by the parasite as required for each specific developmental stage. The remodeling is facilitated by a plethora of exported parasite proteins, and the erythrocyte membrane skeleton is the interface of most of the observed interactions between the parasite and host cell proteins. Host cell remodeling has been extensively described and there is a vast body of information on protein export or the description of parasite-induced structures such as Maurer's clefts or knobs on the host cell surface. Here we specifically review the molecular level of each host cell-remodeling step at each stage of the intraerythrocytic development of P. falciparum We describe key events, such as invasion, knob formation, and egress, and identify the interactions between exported parasite proteins and the host cell cytoskeleton. We discuss each remodeling step with respect to time and specific requirement of the developing parasite to explain host cell remodeling in a stage-specific manner. Thus, we highlight the interaction with the host membrane skeleton as a key event in parasite survival.
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13
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Kumar V, Behl A, Sharma R, Sharma A, Hora R. Plasmodium helical interspersed subtelomeric family-an enigmatic piece of the Plasmodium biology puzzle. Parasitol Res 2019; 118:2753-2766. [PMID: 31418110 DOI: 10.1007/s00436-019-06420-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 08/02/2019] [Indexed: 11/27/2022]
Abstract
Plasmodium falciparum (Pf) refurbishes the infected erythrocytes by exporting a myriad of parasite proteins to the host cell. A novel exported protein family 'Plasmodium Helical Interspersed Subtelomeric' (PHIST) has gained attention for its significant roles in parasite biology. Here, we have collected and analysed available information on PHIST members to enhance understanding of their functions, varied localization and structure-function correlation. Functional diversity of PHIST proteins is highlighted by their involvement in PfEMP1 (Pf erythrocyte membrane protein 1) expression, trafficking and switching. This family also contributes to cytoadherence, gametocytogenesis, host cell modification and generation of extracellular vesicles. While the PHIST domain forms the hallmark of this family, existence and functions of additional domains (LyMP, TIGR01639) and the MEC motif underscores its diversity further. Since specific PHIST proteins seem to form pairs with PfEMP1 members, we have used in silico tools to predict such potential partners in Pf. This information and our analysis of structural data on a PHIST member provide important insights into their functioning. This review overall enables readers to view the PHIST family comprehensively, while highlighting key knowledge gaps in the field.
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Affiliation(s)
- Vikash Kumar
- Department of Molecular Biology and Biochemistry, Guru Nanak Dev University, Amritsar, Punjab, India
| | - Ankita Behl
- Department of Biotechnology, Guru Nanak Dev University, Amritsar, Punjab, India
| | - Rachana Sharma
- Department of Molecular Biology and Biochemistry, Guru Nanak Dev University, Amritsar, Punjab, India
| | - Aanchal Sharma
- Department of Molecular Biology and Biochemistry, Guru Nanak Dev University, Amritsar, Punjab, India
| | - Rachna Hora
- Department of Molecular Biology and Biochemistry, Guru Nanak Dev University, Amritsar, Punjab, India.
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14
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Takano R, Kozuka-Hata H, Kondoh D, Bochimoto H, Oyama M, Kato K. A High-Resolution Map of SBP1 Interactomes in Plasmodium falciparum-infected Erythrocytes. iScience 2019; 19:703-714. [PMID: 31476617 PMCID: PMC6728614 DOI: 10.1016/j.isci.2019.07.035] [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: 12/17/2018] [Revised: 05/09/2019] [Accepted: 07/19/2019] [Indexed: 11/19/2022] Open
Abstract
The pathogenesis of malaria parasites depends on host erythrocyte modifications that are facilitated by parasite proteins exported to the host cytoplasm. These exported proteins form a trafficking complex in the host cytoplasm that transports virulence determinants to the erythrocyte surface; this complex is thus essential for malaria virulence. Here, we report a comprehensive interaction network map of this complex. We developed authentic, unbiased, highly sensitive proteomic approaches to determine the proteins that interact with a core component of the complex, SBP1 (skeleton-binding protein 1). SBP1 interactomes revealed numerous exported proteins and potential interactors associated with SBP1 intracellular trafficking. We identified several host-parasite protein interactions and linked the exported protein MAL8P1.4 to Plasmodium falciparum virulence in infected erythrocytes. Our study highlights the complicated interplay between parasite and host proteins in the host cytoplasm and provides an interaction dataset connecting dozens of exported proteins required for P. falciparum virulence. We used shotgun proteomics to identify SBP1-interacting factors System validation showed complex interplay between parasite and host proteins Our system can be used to explore protozoan parasite virulence in erythrocytes
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Affiliation(s)
- Ryo Takano
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido 080-8555, Japan
| | - Hiroko Kozuka-Hata
- Medical Proteomics Laboratory, Institute of Medical Science, The University of Tokyo, Minato-ku, Tokyo 108-8639, Japan
| | - Daisuke Kondoh
- Laboratory of Veterinary Anatomy, Department of Basic Veterinary Medicine, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido 080-8555, Japan
| | - Hiroki Bochimoto
- Health Care Administration Center, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido 080-8555, Japan
| | - Masaaki Oyama
- Medical Proteomics Laboratory, Institute of Medical Science, The University of Tokyo, Minato-ku, Tokyo 108-8639, Japan
| | - Kentaro Kato
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido 080-8555, Japan; Laboratory of Sustainable Animal Environment, Graduate School of Agricultural Science, Tohoku University, Naruko-onsen, Osaki, Miyagi 989-6711, Japan.
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15
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Wu Y, Wagstaff SC, Al-Harthi SA, Craig AG. Comparative 1D Blue-Native electrophoresis analysis of Plasmodium falciparum and human proteins associated with cytoadherence. Malar J 2018; 17:293. [PMID: 30103779 PMCID: PMC6090645 DOI: 10.1186/s12936-018-2445-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 08/04/2018] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND To understand more about changes to the molecular components that occur when host endothelium interacts with Plasmodium falciparum-infected erythrocytes, a combined technique of protein separation (1D Blue-Native electrophoresis) and mass spectrometry of infected erythrocytes with endothelial cells (EC) in a co-culture system has been used. METHODS Native proteins were extracted from co-cultures and identified by mass spectrometry. Proteomic data from different parasite strains, either adhesion proficient (to endothelial cells) or non-adherent, were analysed in parallel to reveal protein associations linked to cytoadherence. Informatic approaches were developed to facilitate this comparison. RESULTS Blue-Native gel separation and LC/MS/MS identification revealed major differences in samples produced from endothelial cell co-culture with adherent and non-adherent parasite strains. This approach enabled us to identify protein associations seen only with the adhesion proficient parasite strain. CONCLUSIONS The combination of proteomic and analytical approaches has identified differences between adherent and non-adherent parasite lines in co-culture with EC, providing potential candidates for complexes or associations formed during cytoadherence involved in cell structure, signalling and apoptosis.
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Affiliation(s)
- Yang Wu
- Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
- The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
| | - Simon C Wagstaff
- Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Saeed A Al-Harthi
- Department of Parasitology, Faculty of Medicine, Umm AL-Qura University, Makkah, Kingdom of Saudi Arabia
| | - Alister G Craig
- Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK.
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16
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Bunnik EM, Cook KB, Varoquaux N, Batugedara G, Prudhomme J, Cort A, Shi L, Andolina C, Ross LS, Brady D, Fidock DA, Nosten F, Tewari R, Sinnis P, Ay F, Vert JP, Noble WS, Le Roch KG. Changes in genome organization of parasite-specific gene families during the Plasmodium transmission stages. Nat Commun 2018; 9:1910. [PMID: 29765020 PMCID: PMC5954139 DOI: 10.1038/s41467-018-04295-5] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 04/18/2018] [Indexed: 12/20/2022] Open
Abstract
The development of malaria parasites throughout their various life cycle stages is coordinated by changes in gene expression. We previously showed that the three-dimensional organization of the Plasmodium falciparum genome is strongly associated with gene expression during its replication cycle inside red blood cells. Here, we analyze genome organization in the P. falciparum and P. vivax transmission stages. Major changes occur in the localization and interactions of genes involved in pathogenesis and immune evasion, host cell invasion, sexual differentiation, and master regulation of gene expression. Furthermore, we observe reorganization of subtelomeric heterochromatin around genes involved in host cell remodeling. Depletion of heterochromatin protein 1 (PfHP1) resulted in loss of interactions between virulence genes, confirming that PfHP1 is essential for maintenance of the repressive center. Our results suggest that the three-dimensional genome structure of human malaria parasites is strongly connected with transcriptional activity of specific gene families throughout the life cycle.
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Affiliation(s)
- Evelien M Bunnik
- Department of Microbiology, Immunology & Molecular Genetics, The University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX, 78229, USA
- Department of Molecular, Cell and Systems Biology, University of California Riverside, 900 University Ave, Riverside, CA, 92521, USA
| | - Kate B Cook
- Department of Genome Sciences, University of Washington, 3720 15th Ave NE, Seattle, WA, 98195, USA
| | - Nelle Varoquaux
- Department of Statistics, University of California, 367 Evans Hall, Berkeley, CA, 94720, USA
- Berkeley Institute for Data Science, 190 Doe Library, Berkeley, CA, 94720, USA
- MINES ParisTech, PSL Research University, CBIO-Centre for Computational Biology, 60 boulevard Saint-Michel, 75006, Paris, France
- Institut Curie, 75248, Paris, France
- U900, INSERM, Paris, 75248, France
| | - Gayani Batugedara
- Department of Molecular, Cell and Systems Biology, University of California Riverside, 900 University Ave, Riverside, CA, 92521, USA
| | - Jacques Prudhomme
- Department of Molecular, Cell and Systems Biology, University of California Riverside, 900 University Ave, Riverside, CA, 92521, USA
| | - Anthony Cort
- Department of Molecular, Cell and Systems Biology, University of California Riverside, 900 University Ave, Riverside, CA, 92521, USA
| | - Lirong Shi
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, 615N. Wolfe Street, E5132, Baltimore, MD, 21205, USA
| | - Chiara Andolina
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine Research building, University of Oxford, Old Road campus, Roosevelt Drive, Headington, Oxford, OX3 7FZ, UK
- Shoklo Malaria Research Unit, Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot, Tak, 63110, Thailand
| | - Leila S Ross
- Department of Microbiology and Immunology, Columbia University Medical Center, 701W. 168 St., HHSC 1208, New York, NY, 10032, USA
| | - Declan Brady
- School of Life Sciences, Queens Medical Centre, University of Nottingham, Nottingham, NG7 2UH, UK
| | - David A Fidock
- Department of Microbiology and Immunology, Columbia University Medical Center, 701W. 168 St., HHSC 1208, New York, NY, 10032, USA
- Division of Infectious Diseases, Department of Medicine, Columbia University, New York, NY, 10032, USA
| | - Francois Nosten
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine Research building, University of Oxford, Old Road campus, Roosevelt Drive, Headington, Oxford, OX3 7FZ, UK
- Shoklo Malaria Research Unit, Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot, Tak, 63110, Thailand
| | - Rita Tewari
- School of Life Sciences, Queens Medical Centre, University of Nottingham, Nottingham, NG7 2UH, UK
| | - Photini Sinnis
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, 615N. Wolfe Street, E5132, Baltimore, MD, 21205, USA
| | - Ferhat Ay
- La Jolla Institute for Allergy & Immunology, 9420 Athena Cir, La Jolla, CA, 92037, USA
| | - Jean-Philippe Vert
- MINES ParisTech, PSL Research University, CBIO-Centre for Computational Biology, 60 boulevard Saint-Michel, 75006, Paris, France
- Institut Curie, 75248, Paris, France
- U900, INSERM, Paris, 75248, France
- Département de mathématiques et applications, École normale supérieure, CNRS, PSL Research University, Paris, 75005, France
| | - William Stafford Noble
- Department of Genome Sciences, University of Washington, 3720 15th Ave NE, Seattle, WA, 98195, USA.
- Department of Computer Science and Engineering, University of Washington, Seattle, WA, 98195, USA.
| | - Karine G Le Roch
- Department of Molecular, Cell and Systems Biology, University of California Riverside, 900 University Ave, Riverside, CA, 92521, USA.
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17
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Davies HM, Nofal SD, McLaughlin EJ, Osborne AR. Repetitive sequences in malaria parasite proteins. FEMS Microbiol Rev 2018; 41:923-940. [PMID: 29077880 DOI: 10.1093/femsre/fux046] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 09/13/2017] [Indexed: 12/13/2022] Open
Abstract
Five species of parasite cause malaria in humans with the most severe disease caused by Plasmodium falciparum. Many of the proteins encoded in the P. falciparum genome are unusually enriched in repetitive low-complexity sequences containing a limited repertoire of amino acids. These repetitive sequences expand and contract dynamically and are among the most rapidly changing sequences in the genome. The simplest repetitive sequences consist of single amino acid repeats such as poly-asparagine tracts that are found in approximately 25% of P. falciparum proteins. More complex repeats of two or more amino acids are also common in diverse parasite protein families. There is no universal explanation for the occurrence of repetitive sequences and it is possible that many confer no function to the encoded protein and no selective advantage or disadvantage to the parasite. However, there are increasing numbers of examples where repetitive sequences are important for parasite protein function. We discuss the diverse roles of low-complexity repetitive sequences throughout the parasite life cycle, from mediating protein-protein interactions to enabling the parasite to evade the host immune system.
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Affiliation(s)
- Heledd M Davies
- The Francis Crick Institute, London, NW1 1AT, United Kingdom
| | - Stephanie D Nofal
- London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, United Kingdom
| | - Emilia J McLaughlin
- Institute of Structural and Molecular Biology, University College London, Gower Street, London WC1E 6BT, United Kingdom
| | - Andrew R Osborne
- Institute of Structural and Molecular Biology, University College London, Gower Street, London WC1E 6BT, United Kingdom.,Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck, Malet Street, London, WC1E 7HX, United Kingdom
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18
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The Plasmodium falciparum transcriptome in severe malaria reveals altered expression of genes involved in important processes including surface antigen-encoding var genes. PLoS Biol 2018; 16:e2004328. [PMID: 29529020 PMCID: PMC5864071 DOI: 10.1371/journal.pbio.2004328] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 03/22/2018] [Accepted: 02/16/2018] [Indexed: 01/13/2023] Open
Abstract
Within the human host, the malaria parasite Plasmodium falciparum is exposed to multiple selection pressures. The host environment changes dramatically in severe malaria, but the extent to which the parasite responds to-or is selected by-this environment remains unclear. From previous studies, the parasites that cause severe malaria appear to increase expression of a restricted but poorly defined subset of the PfEMP1 variant, surface antigens. PfEMP1s are major targets of protective immunity. Here, we used RNA sequencing (RNAseq) to analyse gene expression in 44 parasite isolates that caused severe and uncomplicated malaria in Papuan patients. The transcriptomes of 19 parasite isolates associated with severe malaria indicated that these parasites had decreased glycolysis without activation of compensatory pathways; altered chromatin structure and probably transcriptional regulation through decreased histone methylation; reduced surface expression of PfEMP1; and down-regulated expression of multiple chaperone proteins. Our RNAseq also identified novel associations between disease severity and PfEMP1 transcripts, domains, and smaller sequence segments and also confirmed all previously reported associations between expressed PfEMP1 sequences and severe disease. These findings will inform efforts to identify vaccine targets for severe malaria and also indicate how parasites adapt to-or are selected by-the host environment in severe malaria.
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19
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Kumar V, Kaur J, Singh AP, Singh V, Bisht A, Panda JJ, Mishra PC, Hora R. PHIST
c protein family members localize to different subcellular organelles and bind
Plasmodium falciparum
major virulence factor
Pf
EMP
‐1. FEBS J 2017; 285:294-312. [DOI: 10.1111/febs.14340] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Revised: 10/15/2017] [Accepted: 11/15/2017] [Indexed: 01/14/2023]
Affiliation(s)
- Vikash Kumar
- Department of Molecular Biology and Biochemistry Guru Nanak Dev University Amritsar India
| | - Jasweer Kaur
- Department of Molecular Biology and Biochemistry Guru Nanak Dev University Amritsar India
| | - Amrit P. Singh
- Department of Pharmaceutical Sciences Guru Nanak Dev University Amritsar India
| | - Vineeta Singh
- National Institute of Malaria Research New Delhi India
| | - Anjali Bisht
- Institute of Nano Science and Technology Mohali India
| | | | - Prakash C. Mishra
- Department of Biotechnology Guru Nanak Dev University Amritsar India
| | - Rachna Hora
- Department of Molecular Biology and Biochemistry Guru Nanak Dev University Amritsar India
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20
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Sherling ES, van Ooij C. Host cell remodeling by pathogens: the exomembrane system in Plasmodium-infected erythrocytes. FEMS Microbiol Rev 2017; 40:701-21. [PMID: 27587718 PMCID: PMC5007283 DOI: 10.1093/femsre/fuw016] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/18/2016] [Indexed: 12/22/2022] Open
Abstract
Malaria is caused by infection of erythrocytes by parasites of the genus Plasmodium. To survive inside erythrocytes, these parasites induce sweeping changes within the host cell, one of the most dramatic of which is the formation of multiple membranous compartments, collectively referred to as the exomembrane system. As an uninfected mammalian erythrocyte is devoid of internal membranes, the parasite must be the force and the source behind the formation of these compartments. Even though the first evidence of the presence these of internal compartments was obtained over a century ago, their functions remain mostly unclear, and in some cases completely unknown, and the mechanisms underlying their formation are still mysterious. In this review, we provide an overview of the different parts of the exomembrane system, describing the parasitophorous vacuole, the tubovesicular network, Maurer's clefts, the caveola-vesicle complex, J dots and other mobile compartments, and the small vesicles that have been observed in Plasmodium-infected cells. Finally, we combine the data into a simplified view of the exomembrane system and its relation to the alterations of the host erythrocyte. Plasmodium parasites remodel the host erythrocyte in various ways, including the formation of several membranous compartments, together referred to as the exomembrane system, within the erythrocyte cytosol that together are key to the sweeping changes in the host cell.
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Affiliation(s)
- Emma S Sherling
- The Francis Crick Institute, Mill Hill Laboratory, Mill Hill, London NW7 1AA, UK Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Christiaan van Ooij
- The Francis Crick Institute, Mill Hill Laboratory, Mill Hill, London NW7 1AA, UK
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21
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Structural analysis of P. falciparum KAHRP and PfEMP1 complexes with host erythrocyte spectrin suggests a model for cytoadherent knob protrusions. PLoS Pathog 2017; 13:e1006552. [PMID: 28806784 PMCID: PMC5570508 DOI: 10.1371/journal.ppat.1006552] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 08/24/2017] [Accepted: 07/25/2017] [Indexed: 11/19/2022] Open
Abstract
Plasmodium falciparum Erythrocyte Membrane Protein 1 (PfEMP1) and Knob-associated Histidine-rich Protein (KAHRP) are directly linked to malaria pathology. PfEMP1 and KAHRP cluster on protrusions (knobs) on the P. falciparum-infected erythrocyte surface and enable pathogenic cytoadherence of infected erythrocytes to the host microvasculature, leading to restricted blood flow, oxygen deprivation and damage of tissues. Here we characterize the interactions of PfEMP1 and KAHRP with host erythrocyte spectrin using biophysical, structural and computational approaches. These interactions assist knob formation and, thus, promote cytoadherence. We show that the folded core of the PfEMP1 cytosolic domain interacts broadly with erythrocyte spectrin but shows weak, residue-specific preference for domain 17 of α spectrin, which is proximal to the erythrocyte cytoskeletal junction. In contrast, a protein sequence repeat region in KAHRP preferentially associates with domains 10–14 of β spectrin, proximal to the spectrin–ankyrin complex. Structural models of PfEMP1 and KAHRP with spectrin combined with previous microscopy and protein interaction data suggest a model for knob architecture. Formation of cytoadherent knobs on the surface of P. falciparum infected erythrocytes correlates with malaria pathology. Two parasite proteins central for knob formation and cytoadherence, KAHRP and PfEMP1, have previously been shown to bind the erythrocyte cytoskeleton. Both KAHRP and PfEMP1 include large segments of protein disorder, which have previously hampered their analysis. In this study we use biophysics and structural biology tools to analyze the interactions between these proteins and host spectrin. We devise a novel computational tool to help us towards this goal that may be broadly applicable to characterizing other complexes of widespread, disordered Plasmodial proteins and host components. We derive atomistic models of KAHRP–spectrin and PfEMP1 –spectrin complexes, and integrate these into an emerging model of knob architecture.
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22
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Counihan NA, Chisholm SA, Bullen HE, Srivastava A, Sanders PR, Jonsdottir TK, Weiss GE, Ghosh S, Crabb BS, Creek DJ, Gilson PR, de Koning-Ward TF. Plasmodium falciparum parasites deploy RhopH2 into the host erythrocyte to obtain nutrients, grow and replicate. eLife 2017; 6. [PMID: 28252383 PMCID: PMC5365316 DOI: 10.7554/elife.23217] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2016] [Accepted: 02/26/2017] [Indexed: 11/13/2022] Open
Abstract
Plasmodium falciparum parasites, the causative agents of malaria, modify their host erythrocyte to render them permeable to supplementary nutrient uptake from the plasma and for removal of toxic waste. Here we investigate the contribution of the rhoptry protein RhopH2, in the formation of new permeability pathways (NPPs) in Plasmodium-infected erythrocytes. We show RhopH2 interacts with RhopH1, RhopH3, the erythrocyte cytoskeleton and exported proteins involved in host cell remodeling. Knockdown of RhopH2 expression in cycle one leads to a depletion of essential vitamins and cofactors and decreased de novo synthesis of pyrimidines in cycle two. There is also a significant impact on parasite growth, replication and transition into cycle three. The uptake of solutes that use NPPs to enter erythrocytes is also reduced upon RhopH2 knockdown. These findings provide direct genetic support for the contribution of the RhopH complex in NPP activity and highlight the importance of NPPs to parasite survival.
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Affiliation(s)
| | | | | | - Anubhav Srivastava
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
| | | | - Thorey K Jonsdottir
- Burnet Institute, Melbourne, Australia.,Department of Medicine, University of Melbourne, Parkville, Australia
| | | | - Sreejoyee Ghosh
- School of Medicine, Deakin University, Waurn Ponds, Australia
| | - Brendan S Crabb
- Burnet Institute, Melbourne, Australia.,Department of Medicine, University of Melbourne, Parkville, Australia.,Monash University, Melbourne, Australia
| | - Darren J Creek
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
| | - Paul R Gilson
- Burnet Institute, Melbourne, Australia.,Monash University, Melbourne, Australia
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23
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Proteomic analysis of exported chaperone/co-chaperone complexes of P. falciparum reveals an array of complex protein-protein interactions. Sci Rep 2017; 7:42188. [PMID: 28218284 PMCID: PMC5316994 DOI: 10.1038/srep42188] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Accepted: 01/06/2017] [Indexed: 02/07/2023] Open
Abstract
Malaria parasites modify their human host cell, the mature erythrocyte. This modification is mediated by a large number of parasite proteins that are exported to the host cell, and is also the underlying cause for the pathology caused by malaria infection. Amongst these proteins are many Hsp40 co-chaperones, and a single Hsp70. These proteins have been implicated in several processes in the host cell, including a potential role in protein transport, however the further molecular players in this process remain obscure. To address this, we have utilized chemical cross-linking followed by mass spectrometry and immunoblotting to isolate and characterize proteins complexes containing an exported Hsp40 (PFE55), and the only known exported Hsp70 (PfHsp70x). Our data reveal that both of these proteins are contained in high molecular weight protein complexes. These complexes are found both in the infected erythrocyte, and within the parasite-derived compartment referred to as the parasitophorous vacuole. Surprisingly, our data also reveal an association of PfHsp70x with components of PTEX, a putative protein translocon within the membrane of the parasitophorous vacuole. Our results suggest that the P. falciparum- infected human erythrocyte contains numerous high molecular weight protein complexes, which may potentially be involved in host cell modification.
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Tools for attenuation of gene expression in malaria parasites. Int J Parasitol 2017; 47:385-398. [PMID: 28153780 DOI: 10.1016/j.ijpara.2016.11.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Revised: 09/15/2016] [Accepted: 11/28/2016] [Indexed: 12/30/2022]
Abstract
An understanding of the biology of Plasmodium parasites, which are the causative agents of the disease malaria, requires study of gene function. Various reverse genetic tools have been described for determining gene function. These tools can be broadly grouped as trans- and cis-acting. Trans-acting tools control gene functions through synthetic nucleic acid probe molecules matching the sequence of the gene of interest. Once delivered to the parasite, the probe engages with the mRNA of the target gene and attenuates its function. Cis-acting tools control gene function through elements introduced into the gene of interest by DNA transfection. The expression of the modified gene can be controlled using external agents, typically small molecule ligands. In this review, we discuss the strengths and weaknesses of these tools to guide researchers in selecting the appropriate tool for studies of gene function, and for guiding future refinements of these tools.
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Davies HM, Thalassinos K, Osborne AR. Expansion of Lysine-rich Repeats in Plasmodium Proteins Generates Novel Localization Sequences That Target the Periphery of the Host Erythrocyte. J Biol Chem 2016; 291:26188-26207. [PMID: 27777305 PMCID: PMC5207086 DOI: 10.1074/jbc.m116.761213] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2016] [Indexed: 01/05/2023] Open
Abstract
Repetitive low complexity sequences, mostly assumed to have no function, are common in proteins that are exported by the malaria parasite into its host erythrocyte. We identify a group of exported proteins containing short lysine-rich tandemly repeated sequences that are sufficient to localize to the erythrocyte periphery, where key virulence-related modifications to the plasma membrane and the underlying cytoskeleton are known to occur. Efficiency of targeting is dependent on repeat number, indicating that novel targeting modules could evolve by expansion of short lysine-rich sequences. Indeed, analysis of fragments of GARP from different species shows that two novel targeting sequences have arisen via the process of repeat expansion in this protein. In the protein Hyp12, the targeting function of a lysine-rich sequence is masked by a neighboring repetitive acidic sequence, further highlighting the importance of repetitive low complexity sequences. We show that sequences capable of targeting the erythrocyte periphery are present in at least nine proteins from Plasmodium falciparum and one from Plasmodium knowlesi. We find these sequences in proteins known to be involved in erythrocyte rigidification and cytoadhesion as well as in previously uncharacterized exported proteins. Together, these data suggest that expansion and contraction of lysine-rich repeats could generate targeting sequences de novo as well as modulate protein targeting efficiency and function in response to selective pressure.
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Affiliation(s)
- Heledd M Davies
- From the Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck and University College London, London WC1E 6BT, United Kingdom
| | - Konstantinos Thalassinos
- From the Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck and University College London, London WC1E 6BT, United Kingdom
| | - Andrew R Osborne
- From the Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck and University College London, London WC1E 6BT, United Kingdom
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Abstract
Malaria continues to impose a significant disease burden on low- and middle-income countries in the tropics. However, revolutionary progress over the last 3 years in nucleic acid sequencing, reverse genetics, and post-genome analyses has generated step changes in our understanding of malaria parasite (Plasmodium spp.) biology and its interactions with its host and vector. Driven by the availability of vast amounts of genome sequence data from Plasmodium species strains, relevant human populations of different ethnicities, and mosquito vectors, researchers can consider any biological component of the malarial process in isolation or in the interactive setting that is infection. In particular, considerable progress has been made in the area of population genomics, with Plasmodium falciparum serving as a highly relevant model. Such studies have demonstrated that genome evolution under strong selective pressure can be detected. These data, combined with reverse genetics, have enabled the identification of the region of the P. falciparum genome that is under selective pressure and the confirmation of the functionality of the mutations in the kelch13 gene that accompany resistance to the major frontline antimalarial, artemisinin. Furthermore, the central role of epigenetic regulation of gene expression and antigenic variation and developmental fate in P. falciparum is becoming ever clearer. This review summarizes recent exciting discoveries that genome technologies have enabled in malaria research and highlights some of their applications to healthcare. The knowledge gained will help to develop surveillance approaches for the emergence or spread of drug resistance and to identify new targets for the development of antimalarial drugs and perhaps vaccines.
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Affiliation(s)
- Sebastian Kirchner
- Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical Veterinary & Life Sciences, University of Glasgow, Glasgow, G12 8TA, UK
| | - B Joanne Power
- Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical Veterinary & Life Sciences, University of Glasgow, Glasgow, G12 8TA, UK
| | - Andrew P Waters
- Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical Veterinary & Life Sciences, University of Glasgow, Glasgow, G12 8TA, UK.
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Plasmodium Helical Interspersed Subtelomeric (PHIST) Proteins, at the Center of Host Cell Remodeling. Microbiol Mol Biol Rev 2016; 80:905-27. [PMID: 27582258 DOI: 10.1128/mmbr.00014-16] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
During the asexual cycle, Plasmodium falciparum extensively remodels the human erythrocyte to make it a suitable host cell. A large number of exported proteins facilitate this remodeling process, which causes erythrocytes to become more rigid, cytoadherent, and permeable for nutrients and metabolic products. Among the exported proteins, a family of 89 proteins, called the Plasmodium helical interspersed subtelomeric (PHIST) protein family, has been identified. While also found in other Plasmodium species, the PHIST family is greatly expanded in P. falciparum. Although a decade has passed since their first description, to date, most PHIST proteins remain uncharacterized and are of unknown function and localization within the host cell, and there are few data on their interactions with other host or parasite proteins. However, over the past few years, PHIST proteins have been mentioned in the literature at an increasing rate owing to their presence at various localizations within the infected erythrocyte. Expression of PHIST proteins has been implicated in molecular and cellular processes such as the surface display of PfEMP1, gametocytogenesis, changes in cell rigidity, and also cerebral and pregnancy-associated malaria. Thus, we conclude that PHIST proteins are central to host cell remodeling, but despite their obvious importance in pathology, PHIST proteins seem to be understudied. Here we review current knowledge, shed light on the definition of PHIST proteins, and discuss these proteins with respect to their localization and probable function. We take into consideration interaction studies, microarray analyses, or data from blood samples from naturally infected patients to combine all available information on this protein family.
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Oberli A, Zurbrügg L, Rusch S, Brand F, Butler ME, Day JL, Cutts EE, Lavstsen T, Vakonakis I, Beck HP. Plasmodium falciparum Plasmodium helical interspersed subtelomeric proteins contribute to cytoadherence and anchor P. falciparum erythrocyte membrane protein 1 to the host cell cytoskeleton. Cell Microbiol 2016; 18:1415-28. [PMID: 26916885 PMCID: PMC5103180 DOI: 10.1111/cmi.12583] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Revised: 02/15/2016] [Accepted: 02/21/2016] [Indexed: 01/12/2023]
Abstract
Adherence of Plasmodium falciparum‐infected erythrocytes to host endothelium is conferred through the parasite‐derived virulence factor P. falciparum erythrocyte membrane protein 1 (PfEMP1), the major contributor to malaria severity. PfEMP1 located at knob structures on the erythrocyte surface is anchored to the cytoskeleton, and the Plasmodium helical interspersed subtelomeric (PHIST) gene family plays a role in many host cell modifications including binding the intracellular domain of PfEMP1. Here, we show that conditional reduction of the PHIST protein PFE1605w strongly reduces adhesion of infected erythrocytes to the endothelial receptor CD36. Adhesion to other endothelial receptors was less affected or even unaltered by PFE1605w depletion, suggesting that PHIST proteins might be optimized for subsets of PfEMP1 variants. PFE1605w does not play a role in PfEMP1 transport, but it directly interacts with both the intracellular segment of PfEMP1 and with cytoskeletal components. This is the first report of a PHIST protein interacting with key molecules of the cytoadherence complex and the host cytoskeleton, and this functional role seems to play an essential role in the pathology of P. falciparum.
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Affiliation(s)
- Alexander Oberli
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Laura Zurbrügg
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Sebastian Rusch
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Françoise Brand
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | | | - Jemma L Day
- Department of Biochemistry, University of Oxford, Oxford, UK
| | - Erin E Cutts
- Department of Biochemistry, University of Oxford, Oxford, UK
| | - Thomas Lavstsen
- Centre for Medical Parasitology, Department of International Health, Immunology, and Microbiology, University of Copenhagen, Copenhagen, Denmark.,Department of Infectious Diseases, Rigshospitalet, Copenhagen, Denmark
| | | | - Hans-Peter Beck
- Swiss Tropical and Public Health Institute, Basel, Switzerland. .,University of Basel, Basel, Switzerland.
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