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Nguyen W, Hodder AN, de Lezongard RB, Czabotar PE, Jarman KE, O'Neill MT, Thompson JK, Jousset Sabroux H, Cowman AF, Boddey JA, Sleebs BE. Enhanced antimalarial activity of plasmepsin V inhibitors by modification of the P 2 position of PEXEL peptidomimetics. Eur J Med Chem 2018; 154:182-198. [PMID: 29800827 DOI: 10.1016/j.ejmech.2018.05.022] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2018] [Revised: 05/14/2018] [Accepted: 05/14/2018] [Indexed: 12/26/2022]
Abstract
Plasmepsin V is an aspartyl protease that plays a critical role in the export of proteins bearing the Plasmodium export element (PEXEL) motif (RxLxQ/E/D) to the infected host erythrocyte, and thus the survival of the malaria parasite. Previously, development of transition state PEXEL mimetic inhibitors of plasmepsin V have primarily focused on demonstrating the importance of the P3 Arg and P1 Leu in binding affinity and selectivity. Here, we investigate the importance of the P2 position by incorporating both natural and non-natural amino acids into this position and show disubstituted beta-carbon amino acids convey the greatest potency. Consequently, we show analogues with either cyclohexylglycine or phenylglycine in the P2 position are the most potent inhibitors of plasmepsin V that impair processing of the PEXEL motif in exported proteins resulting in death of P. falciparum asexual stage parasites.
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Affiliation(s)
- William Nguyen
- The Walter and Eliza Hall Institute of Medical Research, Parkville, 3052, Australia; Department of Medical Biology, The University of Melbourne, Parkville, 3010, Australia
| | - Anthony N Hodder
- The Walter and Eliza Hall Institute of Medical Research, Parkville, 3052, Australia; Department of Medical Biology, The University of Melbourne, Parkville, 3010, Australia
| | - Richard Bestel de Lezongard
- The Walter and Eliza Hall Institute of Medical Research, Parkville, 3052, Australia; Department of Medical Biology, The University of Melbourne, Parkville, 3010, Australia
| | - Peter E Czabotar
- The Walter and Eliza Hall Institute of Medical Research, Parkville, 3052, Australia; Department of Medical Biology, The University of Melbourne, Parkville, 3010, Australia
| | - Kate E Jarman
- The Walter and Eliza Hall Institute of Medical Research, Parkville, 3052, Australia; Department of Medical Biology, The University of Melbourne, Parkville, 3010, Australia
| | - Matthew T O'Neill
- The Walter and Eliza Hall Institute of Medical Research, Parkville, 3052, Australia
| | - Jennifer K Thompson
- The Walter and Eliza Hall Institute of Medical Research, Parkville, 3052, Australia
| | - Helene Jousset Sabroux
- The Walter and Eliza Hall Institute of Medical Research, Parkville, 3052, Australia; Department of Medical Biology, The University of Melbourne, Parkville, 3010, Australia
| | - Alan F Cowman
- The Walter and Eliza Hall Institute of Medical Research, Parkville, 3052, Australia; Department of Medical Biology, The University of Melbourne, Parkville, 3010, Australia
| | - Justin A Boddey
- The Walter and Eliza Hall Institute of Medical Research, Parkville, 3052, Australia; Department of Medical Biology, The University of Melbourne, Parkville, 3010, Australia
| | - Brad E Sleebs
- The Walter and Eliza Hall Institute of Medical Research, Parkville, 3052, Australia; Department of Medical Biology, The University of Melbourne, Parkville, 3010, Australia.
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Kaur J, Hora R. '2TM proteins': an antigenically diverse superfamily with variable functions and export pathways. PeerJ 2018; 6:e4757. [PMID: 29770278 PMCID: PMC5951124 DOI: 10.7717/peerj.4757] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Accepted: 04/23/2018] [Indexed: 11/20/2022] Open
Abstract
Malaria is a disease that affects millions of people annually. An intracellular habitat and lack of protein synthesizing machinery in erythrocytes pose numerous difficulties for survival of the human pathogen Plasmodium falciparum. The parasite refurbishes the infected red blood cell (iRBC) by synthesis and export of several proteins in an attempt to suffice its metabolic needs and evade the host immune response. Immune evasion is largely mediated by surface display of highly polymorphic protein families known as variable surface antigens. These include the two trans-membrane (2TM) superfamily constituted by multicopy repetitive interspersed family (RIFINs), subtelomeric variable open reading frame (STEVORs) and Plasmodium falciparum Maurer's cleft two trans-membrane proteins present only in P. falciparum and some simian infecting Plasmodium species. Their hypervariable region flanked by 2TM domains exposed on the iRBC surface is believed to generate antigenic diversity. Though historically named "2TM superfamily," several A-type RIFINs and some STEVORs assume one trans-membrane topology. RIFINs and STEVORs share varied functions in different parasite life cycle stages like rosetting, alteration of iRBC rigidity and immune evasion. Additionally, a member of the STEVOR family has been implicated in merozoite invasion. Differential expression of these families in laboratory strains and clinical isolates propose them to be important for host cell survival and defense. The role of RIFINs in modulation of host immune response and presence of protective antibodies against these surface exposed molecules in patient sera highlights them as attractive targets of antimalarial therapies and vaccines. 2TM proteins are Plasmodium export elements positive, and several of these are exported to the infected erythrocyte surface after exiting through the classical secretory pathway within parasites. Cleaved and modified proteins are trafficked after packaging in vesicles to reach Maurer's clefts, while information regarding delivery to the iRBC surface is sparse. Expression and export timing of the RIFIN and Plasmodium falciparum erythrocyte membrane protein1 families correspond to each other. Here, we have compiled and comprehended detailed information regarding orthologues, domain architecture, surface topology, functions and trafficking of members of the "2TM superfamily." Considering the large repertoire of proteins included in the 2TM superfamily and recent advances defining their function in malaria biology, a surge in research carried out on this important protein superfamily is likely.
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Affiliation(s)
- Jasweer Kaur
- 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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53
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Böhme U, Otto TD, Cotton JA, Steinbiss S, Sanders M, Oyola SO, Nicot A, Gandon S, Patra KP, Herd C, Bushell E, Modrzynska KK, Billker O, Vinetz JM, Rivero A, Newbold CI, Berriman M. Complete avian malaria parasite genomes reveal features associated with lineage-specific evolution in birds and mammals. Genome Res 2018; 28:547-560. [PMID: 29500236 PMCID: PMC5880244 DOI: 10.1101/gr.218123.116] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 02/28/2018] [Indexed: 01/08/2023]
Abstract
Avian malaria parasites are prevalent around the world and infect a wide diversity of bird species. Here, we report the sequencing and analysis of high-quality draft genome sequences for two avian malaria species, Plasmodium relictum and Plasmodium gallinaceum We identify 50 genes that are specific to avian malaria, located in an otherwise conserved core of the genome that shares gene synteny with all other sequenced malaria genomes. Phylogenetic analysis suggests that the avian malaria species form an outgroup to the mammalian Plasmodium species, and using amino acid divergence between species, we estimate the avian- and mammalian-infective lineages diverged in the order of 10 million years ago. Consistent with their phylogenetic position, we identify orthologs of genes that had previously appeared to be restricted to the clades of parasites containing Plasmodium falciparum and Plasmodium vivax, the species with the greatest impact on human health. From these orthologs, we explore differential diversifying selection across the genus and show that the avian lineage is remarkable in the extent to which invasion-related genes are evolving. The subtelomeres of the P. relictum and P. gallinaceum genomes contain several novel gene families, including an expanded surf multigene family. We also identify an expansion of reticulocyte binding protein homologs in P. relictum, and within these proteins, we detect distinct regions that are specific to nonhuman primate, humans, rodent, and avian hosts. For the first time in the Plasmodium lineage, we find evidence of transposable elements, including several hundred fragments of LTR-retrotransposons in both species and an apparently complete LTR-retrotransposon in the genome of P. gallinaceum.
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Affiliation(s)
- Ulrike Böhme
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, United Kingdom
| | - Thomas D Otto
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, United Kingdom
| | - James A Cotton
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, United Kingdom
| | - Sascha Steinbiss
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, United Kingdom
| | - Mandy Sanders
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, United Kingdom
| | - Samuel O Oyola
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, United Kingdom
- International Livestock Research Institute, Nairobi 00100, Kenya
| | - Antoine Nicot
- CEFE UMR 5175, CNRS-Université de Montpellier-Université Paul-Valéry Montpellier-EPHE, 34293 Montpellier Cedex 5, France
| | - Sylvain Gandon
- CEFE UMR 5175, CNRS-Université de Montpellier-Université Paul-Valéry Montpellier-EPHE, 34293 Montpellier Cedex 5, France
| | - Kailash P Patra
- Department of Medicine, Division of Infectious Diseases, University of California San Diego, School of Medicine, La Jolla, California 92093, USA
| | - Colin Herd
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, United Kingdom
| | - Ellen Bushell
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, United Kingdom
| | - Katarzyna K Modrzynska
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, United Kingdom
| | - Oliver Billker
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, United Kingdom
| | - Joseph M Vinetz
- Department of Medicine, Division of Infectious Diseases, University of California San Diego, School of Medicine, La Jolla, California 92093, USA
| | - Ana Rivero
- MIVEGEC (CNRS UMR 5290), 34394 Montpellier Cedex 5, France
| | - Chris I Newbold
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, United Kingdom
- Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DS, United Kingdom
| | - Matthew Berriman
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, United Kingdom
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54
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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: 30] [Impact Index Per Article: 5.0] [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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55
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Morita M, Nagaoka H, Ntege EH, Kanoi BN, Ito D, Nakata T, Lee JW, Tokunaga K, Iimura T, Torii M, Tsuboi T, Takashima E. PV1, a novel Plasmodium falciparum merozoite dense granule protein, interacts with exported protein in infected erythrocytes. Sci Rep 2018; 8:3696. [PMID: 29487358 PMCID: PMC5829233 DOI: 10.1038/s41598-018-22026-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 02/07/2018] [Indexed: 01/09/2023] Open
Abstract
Upon invasion, Plasmodium falciparum exports hundreds of proteins across its surrounding parasitophorous vacuole membrane (PVM) to remodel the infected erythrocyte. Although this phenomenon is crucial for the parasite growth and virulence, elucidation of precise steps in the export pathway is still required. A translocon protein complex, PTEX, is the only known pathway that mediates passage of exported proteins across the PVM. P. falciparum Parasitophorous Vacuolar protein 1 (PfPV1), a previously reported parasitophorous vacuole (PV) protein, is considered essential for parasite growth. In this study, we characterized PfPV1 as a novel merozoite dense granule protein. Structured illumination microscopy (SIM) analyses demonstrated that PfPV1 partially co-localized with EXP2, suggesting the protein could be a PTEX accessory molecule. Furthermore, PfPV1 and exported protein PTP5 co-immunoprecipitated with anti-PfPV1 antibody. Surface plasmon resonance (SPR) confirmed the proteins’ direct interaction. Additionally, we identified a PfPV1 High-affinity Region (PHR) at the C-terminal side of PTP5 where PfPV1 dominantly bound. SIM analysis demonstrated an export arrest of PTP5ΔPHR, a PTP5 mutant lacking PHR, suggesting PHR is essential for PTP5 export to the infected erythrocyte cytosol. The overall results suggest that PfPV1, a novel dense granule protein, plays an important role in protein export at PV.
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Affiliation(s)
- Masayuki Morita
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Ehime, Japan
| | - Hikaru Nagaoka
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Ehime, Japan
| | - Edward H Ntege
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Ehime, Japan
| | - Bernard N Kanoi
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Ehime, Japan
| | - Daisuke Ito
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Ehime, Japan.,Division of Medical Zoology, Department of Microbiology and Immunology, Faculty of Medicine, Tottori University, Yonago, Tottori, 683-8503, Japan
| | - Takahiro Nakata
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Ehime, Japan
| | - Ji-Won Lee
- Division of Bio-Imaging, Proteo-Science Center, Ehime University, Shitsukawa, Toon, Ehime, Japan
| | | | - Tadahiro Iimura
- Division of Bio-Imaging, Proteo-Science Center, Ehime University, Shitsukawa, Toon, Ehime, Japan.,Division of Analytical Bio-Medicine, Advanced Research Support Center, Ehime University, Shitsukawa, Toon, Ehime, Japan
| | - Motomi Torii
- Division of Molecular Parasitology, Proteo-Science Center, Ehime University, Shitsukawa, Toon, Ehime, Japan
| | - Takafumi Tsuboi
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Ehime, Japan
| | - Eizo Takashima
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Ehime, Japan.
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56
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Patent Highlights June-July 2017. Pharm Pat Anal 2017; 6:259-266. [PMID: 29064331 DOI: 10.4155/ppa-2017-0034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A snapshot of noteworthy recent developments in the patent literature of relevance to pharmaceutical and medical research and development.
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57
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Shakya B, Penn WD, Nakayasu ES, LaCount DJ. The Plasmodium falciparum exported protein PF3D7_0402000 binds to erythrocyte ankyrin and band 4.1. Mol Biochem Parasitol 2017; 216:5-13. [PMID: 28627360 PMCID: PMC5738903 DOI: 10.1016/j.molbiopara.2017.06.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 05/24/2017] [Accepted: 06/07/2017] [Indexed: 01/12/2023]
Abstract
Plasmodium falciparum extensively modifies the infected red blood cell (RBC), resulting in changes in deformability, shape and surface properties. These alterations suggest that the RBC cytoskeleton is a major target for modification during infection. However, the molecular mechanisms leading to these changes are largely unknown. To begin to address this question, we screened for exported P. falciparum proteins that bound to the erythrocyte cytoskeleton proteins ankyrin 1 (ANK1) and band 4.1 (4.1R), which form critical interactions with other cytoskeletal proteins that contribute to the deformability and stability of RBCs. Yeast two-hybrid screens with ANK1 and 4.1R identified eight interactions with P. falciparum exported proteins, including an interaction between 4.1R and PF3D7_0402000 (PFD0090c). This interaction was first identified in a large-scale screen (Vignali et al., Malaria J, 7:211, 2008), which also reported an interaction between PF3D7_0402000 and ANK1. We confirmed the interactions of PF3D7_0402000 with 4.1R and ANK1 in pair-wise yeast two-hybrid and co-precipitation assays. In both cases, an intact PHIST domain in PF3D7_0402000 was required for binding. Complex purification followed by mass spectrometry analysis provided additional support for the interaction of PF3D7_0402000 with ANK1 and 4.1R. RBC ghost cells loaded with maltose-binding protein (MBP)-PF3D7_0402000 passed through a metal microsphere column less efficiently than mock- or MBP-loaded controls, consistent with an effect of PF3D7_0402000 on RBC rigidity or membrane stability. This study confirmed the interaction of PF3D7_0402000 with 4.1R in multiple independent assays, provided the first evidence that PF3D7_0402000 also binds to ANK1, and suggested that PF3D7_0402000 affects deformability or membrane stability of uninfected RBC ghosts.
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Affiliation(s)
- Bikash Shakya
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907, USA
| | - Wesley D Penn
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907, USA
| | - Ernesto S Nakayasu
- Bindley Bioscience Center, Discovery Park, Purdue University, West Lafayette, IN 47907, USA; Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Douglas J LaCount
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907, USA.
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58
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Pasini EM, Böhme U, Rutledge GG, Voorberg-Van der Wel A, Sanders M, Berriman M, Kocken CH, Otto TD. An improved Plasmodium cynomolgi genome assembly reveals an unexpected methyltransferase gene expansion. Wellcome Open Res 2017; 2:42. [PMID: 28748222 PMCID: PMC5500898 DOI: 10.12688/wellcomeopenres.11864.1] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/15/2017] [Indexed: 11/20/2022] Open
Abstract
Background:
Plasmodium cynomolgi, a non-human primate malaria parasite species, has been an important model parasite since its discovery in 1907. Similarities in the biology of
P. cynomolgi to the closely related, but less tractable, human malaria parasite
P. vivax make it the model parasite of choice for liver biology and vaccine studies pertinent to
P. vivax malaria. Molecular and genome-scale studies of
P. cynomolgi have relied on the current reference genome sequence, which remains highly fragmented with 1,649 unassigned scaffolds and little representation of the subtelomeres. Methods: Using long-read sequence data (Pacific Biosciences SMRT technology), we assembled and annotated a new reference genome sequence, PcyM, sourced from an Indian rhesus monkey. We compare the newly assembled genome sequence with those of several other
Plasmodium species, including a re-annotated
P. coatneyi assembly. Results: The new PcyM genome assembly is of significantly higher quality than the existing reference, comprising only 56 pieces, no gaps and an improved average gene length. Detailed manual curation has ensured a comprehensive annotation of the genome with 6,632 genes, nearly 1,000 more than previously attributed to
P. cynomolgi. The new assembly also has an improved representation of the subtelomeric regions, which account for nearly 40% of the sequence. Within the subtelomeres, we identified more than 1300
Plasmodium interspersed repeat (
pir) genes, as well as a striking expansion of 36 methyltransferase pseudogenes that originated from a single copy on chromosome 9. Conclusions: The manually curated PcyM reference genome sequence is an important new resource for the malaria research community. The high quality and contiguity of the data have enabled the discovery of a novel expansion of methyltransferase in the subtelomeres, and illustrates the new comparative genomics capabilities that are being unlocked by complete reference genomes.
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Affiliation(s)
- Erica M Pasini
- Biomedical Primate Research Centre, Rijswijk, Lange Kleiweg 161, 2288GJ Rijswijk, Netherlands
| | - Ulrike Böhme
- The Wellcome Trust Sanger Institute, Hinxton, Cambridge, CB10 1SA, UK
| | - Gavin G Rutledge
- The Wellcome Trust Sanger Institute, Hinxton, Cambridge, CB10 1SA, UK
| | | | - Mandy Sanders
- The Wellcome Trust Sanger Institute, Hinxton, Cambridge, CB10 1SA, UK
| | - Matt Berriman
- The Wellcome Trust Sanger Institute, Hinxton, Cambridge, CB10 1SA, UK
| | - Clemens Hm Kocken
- Biomedical Primate Research Centre, Rijswijk, Lange Kleiweg 161, 2288GJ Rijswijk, Netherlands
| | - Thomas Dan Otto
- The Wellcome Trust Sanger Institute, Hinxton, Cambridge, CB10 1SA, UK
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59
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Patarroyo ME, Alba MP, Rojas-Luna R, Bermudez A, Aza-Conde J. Functionally relevant proteins in Plasmodium falciparum host cell invasion. Immunotherapy 2017; 9:131-155. [DOI: 10.2217/imt-2016-0091] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A totally effective, antimalarial vaccine must involve sporozoite and merozoite proteins (or their fragments) to ensure complete parasite blocking during critical invasion stages. This Special Report examines proteins involved in critical biological functions for parasite survival and highlights the conserved amino acid sequences of the most important proteins involved in sporozoite invasion of hepatocytes and merozoite invasion of red blood cells. Conserved high activity binding peptides are located in such proteins’ functionally strategic sites, whose functions are related to receptor binding, nutrient and protein transport, enzyme activity and molecule–molecule interactions. They are thus excellent targets for vaccine development as they block proteins binding function involved in invasion and also their biological function.
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Affiliation(s)
- Manuel E Patarroyo
- Fundación Instituto de Inmunología de Colombia (FIDIC), Carrera 50 No. 26–20 Bogotá, Colombia
- Universidad Nacional de Colombia, Bogotá DC, Colombia
| | - Martha P Alba
- Fundación Instituto de Inmunología de Colombia (FIDIC), Carrera 50 No. 26–20 Bogotá, Colombia
- Universidad de Ciencias Aplicadas y Ambientales (UDCA), Bogotá, Colombia
| | - Rocío Rojas-Luna
- Fundación Instituto de Inmunología de Colombia (FIDIC), Carrera 50 No. 26–20 Bogotá, Colombia
| | - Adriana Bermudez
- Fundación Instituto de Inmunología de Colombia (FIDIC), Carrera 50 No. 26–20 Bogotá, Colombia
- Universidad del Rosario, Bogotá DC, Colombia
| | - Jorge Aza-Conde
- Fundación Instituto de Inmunología de Colombia (FIDIC), Carrera 50 No. 26–20 Bogotá, Colombia
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60
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Fougère A, Jackson AP, Paraskevi Bechtsi D, Braks JAM, Annoura T, Fonager J, Spaccapelo R, Ramesar J, Chevalley-Maurel S, Klop O, van der Laan AMA, Tanke HJ, Kocken CHM, Pasini EM, Khan SM, Böhme U, van Ooij C, Otto TD, Janse CJ, Franke-Fayard B. Variant Exported Blood-Stage Proteins Encoded by Plasmodium Multigene Families Are Expressed in Liver Stages Where They Are Exported into the Parasitophorous Vacuole. PLoS Pathog 2016; 12:e1005917. [PMID: 27851824 PMCID: PMC5113031 DOI: 10.1371/journal.ppat.1005917] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Accepted: 09/06/2016] [Indexed: 01/05/2023] Open
Abstract
Many variant proteins encoded by Plasmodium-specific multigene families are exported into red blood cells (RBC). P. falciparum-specific variant proteins encoded by the var, stevor and rifin multigene families are exported onto the surface of infected red blood cells (iRBC) and mediate interactions between iRBC and host cells resulting in tissue sequestration and rosetting. However, the precise function of most other Plasmodium multigene families encoding exported proteins is unknown. To understand the role of RBC-exported proteins of rodent malaria parasites (RMP) we analysed the expression and cellular location by fluorescent-tagging of members of the pir, fam-a and fam-b multigene families. Furthermore, we performed phylogenetic analyses of the fam-a and fam-b multigene families, which indicate that both families have a history of functional differentiation unique to RMP. We demonstrate for all three families that expression of family members in iRBC is not mutually exclusive. Most tagged proteins were transported into the iRBC cytoplasm but not onto the iRBC plasma membrane, indicating that they are unlikely to play a direct role in iRBC-host cell interactions. Unexpectedly, most family members are also expressed during the liver stage, where they are transported into the parasitophorous vacuole. This suggests that these protein families promote parasite development in both the liver and blood, either by supporting parasite development within hepatocytes and erythrocytes and/or by manipulating the host immune response. Indeed, in the case of Fam-A, which have a steroidogenic acute regulatory-related lipid transfer (START) domain, we found that several family members can transfer phosphatidylcholine in vitro. These observations indicate that these proteins may transport (host) phosphatidylcholine for membrane synthesis. This is the first demonstration of a biological function of any exported variant protein family of rodent malaria parasites. Malaria-parasites invade and multiply in hepatocytes and erythrocytes. The human parasite P. falciparum transports proteins encoded by multigene families onto the surface of erythrocytes, mediating interactions between infected red blood cells (iRBCs) and other host-cells and are thought to play a key role in parasite survival during blood-stage development. The function of other exported Plasmodium protein families remains largely unknown. We provide novel insights into expression and cellular location of proteins encoded by three large multigene families of rodent malaria parasites (Fam-a, Fam-b and PIR). Multiple members of the same family are expressed in a single iRBC, unlike P. falciparum PfEMP1 proteins where individual iRBCs express only a single member. Most proteins we examined are located in the RBC cytoplasm and are not transported onto the iRBC surface membrane, indicating that these proteins are unlikely to mediate interactions between iRBCs and host-cells. Unexpectedly, liver stages also express many of these proteins, where they locate to the vacuole surrounding the parasite inside the hepatocyte. In support of a role of these proteins for parasite growth within their host cells we provide evidence that Fam-A proteins have a role in uptake and transport of (host) phosphatidylcholine for parasite-membrane synthesis.
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Affiliation(s)
- Aurélie Fougère
- Leiden Malaria Research Group, Parasitology, Center of infectious Diseases, Leiden University Medical Center (LUMC), Leiden, The Netherlands
- Department of Experimental Medicine, University of Perugia, Italy
| | - Andrew P. Jackson
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool, UnitedKingdom
| | | | - Joanna A. M. Braks
- Leiden Malaria Research Group, Parasitology, Center of infectious Diseases, Leiden University Medical Center (LUMC), Leiden, The Netherlands
| | - Takeshi Annoura
- Leiden Malaria Research Group, Parasitology, Center of infectious Diseases, Leiden University Medical Center (LUMC), Leiden, The Netherlands
- Department of Department of Parasitology, National Institute of Infectious Diseases (NIID), Tokyo, Japan
| | - Jannik Fonager
- Leiden Malaria Research Group, Parasitology, Center of infectious Diseases, Leiden University Medical Center (LUMC), Leiden, The Netherlands
- Department of Microbiological Diagnostics and Virology, Statens Serum Institute, Copenhagen, Denmark
| | | | - Jai Ramesar
- Leiden Malaria Research Group, Parasitology, Center of infectious Diseases, Leiden University Medical Center (LUMC), Leiden, The Netherlands
| | - Séverine Chevalley-Maurel
- Leiden Malaria Research Group, Parasitology, Center of infectious Diseases, Leiden University Medical Center (LUMC), Leiden, The Netherlands
| | - Onny Klop
- Leiden Malaria Research Group, Parasitology, Center of infectious Diseases, Leiden University Medical Center (LUMC), Leiden, The Netherlands
- Biomedical Primate Research Centre (BPRC), Rijswijk, The Netherlands
| | | | - Hans J. Tanke
- Department of Molecular Cell Biology, Leiden University Medical Center (LUMC), Leiden, The Netherlands
| | | | - Erica M. Pasini
- Biomedical Primate Research Centre (BPRC), Rijswijk, The Netherlands
| | - Shahid M. Khan
- Leiden Malaria Research Group, Parasitology, Center of infectious Diseases, Leiden University Medical Center (LUMC), Leiden, The Netherlands
| | - Ulrike Böhme
- Wellcome Trust Sanger Institute, Hinxton, Cambridge, UnitedKingdom
| | - Christiaan van Ooij
- The Francis Crick Institute, Mill Hill Laboratory, Mill Hill, London, UnitedKingdom
| | - Thomas D. Otto
- Wellcome Trust Sanger Institute, Hinxton, Cambridge, UnitedKingdom
| | - Chris J. Janse
- Leiden Malaria Research Group, Parasitology, Center of infectious Diseases, Leiden University Medical Center (LUMC), Leiden, The Netherlands
| | - Blandine Franke-Fayard
- Leiden Malaria Research Group, Parasitology, Center of infectious Diseases, Leiden University Medical Center (LUMC), Leiden, The Netherlands
- * E-mail:
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Exported Epoxide Hydrolases Modulate Erythrocyte Vasoactive Lipids during Plasmodium falciparum Infection. mBio 2016; 7:mBio.01538-16. [PMID: 27795395 PMCID: PMC5082902 DOI: 10.1128/mbio.01538-16] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Erythrocytes are reservoirs of important epoxide-containing lipid signaling molecules, including epoxyeicosatrienoic acids (EETs). EETs function as vasodilators and anti-inflammatory modulators in the bloodstream. Bioactive EETs are hydrolyzed to less active diols (dihydroxyeicosatrienoic acids) by epoxide hydrolases (EHs). The malaria parasite Plasmodium falciparum infects host red blood cells (RBCs) and exports hundreds of proteins into the RBC compartment. In this study, we show that two parasite epoxide hydrolases, P. falciparum epoxide hydrolases 1 (PfEH1) and 2 (PfEH2), both with noncanonical serine nucleophiles, are exported to the periphery of infected RBCs. PfEH1 and PfEH2 were successfully expressed in Escherichia coli, and they hydrolyzed physiologically relevant erythrocyte EETs. Mutations in active site residues of PfEH1 ablated the ability of the enzyme to hydrolyze an epoxide substrate. Overexpression of PfEH1 or PfEH2 in parasite-infected RBCs resulted in a significant alteration in the epoxide fatty acids stored in RBC phospholipids. We hypothesize that the parasite disruption of epoxide-containing signaling lipids leads to perturbed vascular function, creating favorable conditions for binding and sequestration of infected RBCs to the microvascular endothelium. The malaria parasite exports hundreds of proteins into the erythrocyte compartment. However, for most of these proteins, their physiological function is unknown. In this study, we investigate two “hypothetical” proteins of the α/β-hydrolase fold family that share sequence similarity with epoxide hydrolases (EHs)—enzymes that destroy bioactive epoxides. Altering EH expression in parasite-infected erythrocytes resulted in a significant change in the epoxide fatty acids stored in the host cell. We propose that these EH enzymes may help the parasite to manipulate host blood vessel opening and inflame the vessel walls as they pass through the circulation system. Understanding how the malaria parasite interacts with its host RBCs will aid in our ability to combat this deadly disease.
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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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63
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Ansari HR, Templeton TJ, Subudhi AK, Ramaprasad A, Tang J, Lu F, Naeem R, Hashish Y, Oguike MC, Benavente ED, Clark TG, Sutherland CJ, Barnwell JW, Culleton R, Cao J, Pain A. Genome-scale comparison of expanded gene families in Plasmodium ovale wallikeri and Plasmodium ovale curtisi with Plasmodium malariae and with other Plasmodium species. Int J Parasitol 2016; 46:685-96. [PMID: 27392654 DOI: 10.1016/j.ijpara.2016.05.009] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Revised: 05/26/2016] [Accepted: 05/28/2016] [Indexed: 12/13/2022]
Abstract
Malaria in humans is caused by six species of Plasmodium parasites, of which the nuclear genome sequences for the two Plasmodium ovale spp., P. ovale curtisi and P. ovale wallikeri, and Plasmodium malariae have not yet been analyzed. Here we present an analysis of the nuclear genome sequences of these three parasites, and describe gene family expansions therein. Plasmodium ovale curtisi and P. ovale wallikeri are genetically distinct but morphologically indistinguishable and have sympatric ranges through the tropics of Africa, Asia and Oceania. Both P. ovale spp. show expansion of the surfin variant gene family, and an amplification of the Plasmodium interspersed repeat (pir) superfamily which results in an approximately 30% increase in genome size. For comparison, we have also analyzed the draft nuclear genome of P. malariae, a malaria parasite causing mild malaria symptoms with a quartan life cycle, long-term chronic infections, and wide geographic distribution. Plasmodium malariae shows only a moderate level of expansion of pir genes, and unique expansions of a highly diverged transmembrane protein family with over 550 members and the gamete P25/27 gene family. The observed diversity in the P. ovale wallikeri and P. ovale curtisi surface antigens, combined with their phylogenetic separation, supports consideration that the two parasites be given species status.
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Affiliation(s)
- Hifzur Rahman Ansari
- Pathogen Genomics Laboratory, Biological and Environmental Sciences and Engineering (BESE) Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Jeddah 23955-6900, Saudi Arabia
| | - Thomas J Templeton
- Department of Protozoology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan; Department of Microbiology and Immunology, Weill Cornell Medical College, New York 10021, USA
| | - Amit Kumar Subudhi
- Pathogen Genomics Laboratory, Biological and Environmental Sciences and Engineering (BESE) Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Jeddah 23955-6900, Saudi Arabia
| | - Abhinay Ramaprasad
- Pathogen Genomics Laboratory, Biological and Environmental Sciences and Engineering (BESE) Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Jeddah 23955-6900, Saudi Arabia
| | - Jianxia Tang
- Key Laboratory of National Health and Family Planning Commission on Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, Jiangsu Province, People's Republic of China
| | - Feng Lu
- Key Laboratory of National Health and Family Planning Commission on Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, Jiangsu Province, People's Republic of China
| | - Raeece Naeem
- Pathogen Genomics Laboratory, Biological and Environmental Sciences and Engineering (BESE) Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Jeddah 23955-6900, Saudi Arabia
| | - Yasmeen Hashish
- Pathogen Genomics Laboratory, Biological and Environmental Sciences and Engineering (BESE) Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Jeddah 23955-6900, Saudi Arabia
| | - Mary C Oguike
- Department of Immunology & Infection, Faculty of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Ernest Diez Benavente
- Department of Pathogen Molecular Biology, Faculty of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Taane G Clark
- Department of Pathogen Molecular Biology, Faculty of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom; Department of Infectious Disease Epidemiology, Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Colin J Sutherland
- Department of Immunology & Infection, Faculty of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom; Department of Pathogen Molecular Biology, Faculty of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom; Public Health England Malaria Reference Laboratory, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - John W Barnwell
- Centers for Disease Control and Prevention, Atlanta, GA 30329-4027, USA
| | - Richard Culleton
- Malaria Unit, Department of Pathology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan.
| | - Jun Cao
- Key Laboratory of National Health and Family Planning Commission on Parasitic Disease Control and Prevention, Jiangsu Provincial Key Laboratory on Parasite and Vector Control Technology, Jiangsu Institute of Parasitic Diseases, Wuxi, Jiangsu Province, People's Republic of China.
| | - Arnab Pain
- Pathogen Genomics Laboratory, Biological and Environmental Sciences and Engineering (BESE) Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Jeddah 23955-6900, Saudi Arabia; Global Station for Zoonosis Control, Global Institution for Collaborative Research and Education (GI-CoRE), Hokkaido University, N20 W10 Kita-ku, Sapporo 001-0020, Japan.
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64
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de Koning-Ward TF, Dixon MW, Tilley L, Gilson PR. Plasmodium species: master renovators of their host cells. Nat Rev Microbiol 2016; 14:494-507. [DOI: 10.1038/nrmicro.2016.79] [Citation(s) in RCA: 117] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Gilson PR, Chisholm SA, Crabb BS, de Koning-Ward TF. Host cell remodelling in malaria parasites: a new pool of potential drug targets. Int J Parasitol 2016; 47:119-127. [PMID: 27368610 DOI: 10.1016/j.ijpara.2016.06.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Revised: 06/02/2016] [Accepted: 06/04/2016] [Indexed: 12/01/2022]
Abstract
When in their human hosts, malaria parasites spend most of their time housed within vacuoles inside erythrocytes and hepatocytes. The parasites extensively modify their host cells to obtain nutrients, prevent host cell breakdown and avoid the immune system. To perform these modifications, malaria parasites export hundreds of effector proteins into their host cells and this process is best understood in the most lethal species to infect humans, Plasmodium falciparum. The effector proteins are synthesized within the parasite and following a proteolytic cleavage event in the endoplasmic reticulum and sorting of mature proteins into the correct vesicular trafficking pathway, they are transported to the parasite surface and released into the vacuole. The effector proteins are then unfolded before extrusion across the vacuole membrane by a unique translocon complex called Plasmodium translocon of exported proteins. After gaining access to the erythrocyte cytoplasm many effector proteins continue their journey to the erythrocyte surface by utilising various membranous structures established by the parasite. This complex trafficking pathway and a large number of the effector proteins are unique to Plasmodium parasites. This pathway could, therefore, be developed as new drug targets given that protein export and the functional role of these proteins are essential for parasite survival. This review explores known and potential drug targetable steps in the protein export pathway and strategies for discovering novel drug targets.
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Affiliation(s)
- Paul R Gilson
- Burnet Institute, Melbourne, Victoria, Australia; Monash University, Melbourne, Victoria, Australia.
| | | | - Brendan S Crabb
- Burnet Institute, Melbourne, Victoria, Australia; Monash University, Melbourne, Victoria, Australia; University of Melbourne, Melbourne, Victoria, Australia
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66
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Sojka D, Hartmann D, Bartošová-Sojková P, Dvořák J. Parasite Cathepsin D-Like Peptidases and Their Relevance as Therapeutic Targets. Trends Parasitol 2016; 32:708-723. [PMID: 27344362 DOI: 10.1016/j.pt.2016.05.015] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Revised: 04/27/2016] [Accepted: 05/25/2016] [Indexed: 11/18/2022]
Abstract
Inhibition of aspartic cathepsin D-like peptidases (APDs) has been often discussed as an antiparasite intervention strategy. APDs have been considered as virulence factors of Trypanosoma cruzi and Leishmania spp., and have been demonstrated to have important roles in protein trafficking mechanisms of apicomplexan parasites. APDs also initiate blood digestion as components of multienzyme proteolytic complexes in malaria, platyhelminths, nematodes, and ticks. Increasing DNA and RNA sequencing data indicate that parasites express multiple APD isoenzymes of various functions that can now be specifically evaluated using new functional-genomic and biochemical tools, from which we can further assess the potential of APDs as targets for novel effective intervention strategies against parasitic diseases that still pose an alarming threat to mankind.
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Affiliation(s)
- Daniel Sojka
- Institute of Parasitology, Biology Centre, The Czech Academy of Sciences, Ceske Budejovice 370 05, Czech Republic.
| | - David Hartmann
- Institute of Parasitology, Biology Centre, The Czech Academy of Sciences, Ceske Budejovice 370 05, Czech Republic
| | - Pavla Bartošová-Sojková
- Institute of Parasitology, Biology Centre, The Czech Academy of Sciences, Ceske Budejovice 370 05, Czech Republic
| | - Jan Dvořák
- Institute of Molecular Genetics, The Czech Academy of Sciences, Prague 14220, Czech Republic; Institute of Organic Chemistry and Biochemistry, The Czech Academy of Sciences, Prague 16610, Czech Republic; School of Biological Sciences, Queen's University Belfast, Belfast BT9 7BL, UK
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67
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Przyborski JM, Nyboer B, Lanzer M. Ticket to ride: export of proteins to the Plasmodium falciparum-infected erythrocyte. Mol Microbiol 2016; 101:1-11. [PMID: 26996123 DOI: 10.1111/mmi.13380] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/17/2016] [Indexed: 12/28/2022]
Abstract
The malaria parasite Plasmodium falciparum exports numerous proteins to its chosen host cell, the mature human erythrocyte. Many of these proteins are important for parasite survival. To reach the host cell, parasites must cross multiple membrane barriers and then furthermore be targeted to their correct sub-cellular localisation. This novel transport pathway has received much research attention in the past decades, especially as many of the mechanisms are expected to be parasite-specific and thus potential targets for drug development. In this article we summarize some of the most recent advances in this field, and highlight areas in which further research is needed.
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Affiliation(s)
- Jude M Przyborski
- Parasitology, Faculty of Biology, Philipps University Marburg, Karl von Frisch Strasse 8, 35043, Marburg, Germany
| | - Britta Nyboer
- Center of Infectious Diseases, Parasitology, Heidelberg University, Im Neuenheimer Feld 324, 69120, Heidelberg, Germany
| | - Michael Lanzer
- Center of Infectious Diseases, Parasitology, Heidelberg University, Im Neuenheimer Feld 324, 69120, Heidelberg, Germany
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68
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Elsworth B, Sanders PR, Nebl T, Batinovic S, Kalanon M, Nie CQ, Charnaud SC, Bullen HE, de Koning Ward TF, Tilley L, Crabb BS, Gilson PR. Proteomic analysis reveals novel proteins associated with the Plasmodium protein exporter PTEX and a loss of complex stability upon truncation of the core PTEX component, PTEX150. Cell Microbiol 2016; 18:1551-1569. [PMID: 27019089 DOI: 10.1111/cmi.12596] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Revised: 03/11/2016] [Accepted: 03/22/2016] [Indexed: 11/28/2022]
Abstract
The Plasmodium translocon for exported proteins (PTEX) has been established as the machinery responsible for the translocation of all classes of exported proteins beyond the parasitophorous vacuolar membrane of the intraerythrocytic malaria parasite. Protein export, particularly in the asexual blood stage, is crucial for parasite survival as exported proteins are involved in remodelling the host cell, an essential process for nutrient uptake, waste removal and immune evasion. Here, we have truncated the conserved C-terminus of one of the essential PTEX components, PTEX150, in Plasmodium falciparum in an attempt to create mutants of reduced functionality. Parasites tolerated C-terminal truncations of up to 125 amino acids with no reduction in growth, protein export or the establishment of new permeability pathways. Quantitative proteomic approaches however revealed a decrease in other PTEX subunits associating with PTEX150 in truncation mutants, suggesting a role for the C-terminus of PTEX150 in regulating PTEX stability. Our analyses also reveal three previously unreported PTEX-associated proteins, namely PV1, Pf113 and Hsp70-x (respective PlasmoDB numbers; PF3D7_1129100, PF3D7_1420700 and PF3D7_0831700) and demonstrate that core PTEX proteins exist in various distinct multimeric forms outside the major complex.
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Affiliation(s)
- Brendan Elsworth
- Burnet Institute, 85 Commercial Road, Melbourne, VIC, 3004, Australia.,Monash University, Melbourne, VIC, 3800, Australia
| | - Paul R Sanders
- Burnet Institute, 85 Commercial Road, Melbourne, VIC, 3004, Australia
| | - Thomas Nebl
- Walter & Eliza Hall Institute, Melbourne, VIC, 3052, Australia
| | - Steven Batinovic
- Department of Biochemistry and Molecular Biology, The University of Melbourne, Melbourne, VIC, Australia.,ARC Centre of Excellence for Coherent X-ray Science, The University of Melbourne, Melbourne, VIC, Australia.,Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC, Australia
| | | | - Catherine Q Nie
- Burnet Institute, 85 Commercial Road, Melbourne, VIC, 3004, Australia
| | - Sarah C Charnaud
- Burnet Institute, 85 Commercial Road, Melbourne, VIC, 3004, Australia.,Monash University, Melbourne, VIC, 3800, Australia
| | - Hayley E Bullen
- Burnet Institute, 85 Commercial Road, Melbourne, VIC, 3004, Australia
| | | | - Leann Tilley
- Department of Biochemistry and Molecular Biology, The University of Melbourne, Melbourne, VIC, Australia.,ARC Centre of Excellence for Coherent X-ray Science, The University of Melbourne, Melbourne, VIC, Australia.,Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC, Australia
| | - Brendan S Crabb
- Burnet Institute, 85 Commercial Road, Melbourne, VIC, 3004, Australia.,Monash University, Melbourne, VIC, 3800, Australia.,University of Melbourne, Melbourne, VIC, 3010, Australia
| | - Paul R Gilson
- Burnet Institute, 85 Commercial Road, Melbourne, VIC, 3004, Australia. .,Monash University, Melbourne, VIC, 3800, Australia.
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69
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Role of the ER and Golgi in protein export by Apicomplexa. Curr Opin Cell Biol 2016; 41:18-24. [PMID: 27019341 DOI: 10.1016/j.ceb.2016.03.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Revised: 03/06/2016] [Accepted: 03/07/2016] [Indexed: 12/31/2022]
Abstract
Apicomplexan parasites cause diseases of medical and agricultural importance linked to dramatic changes they impart upon infected host cells. Following invasion, the malaria parasite Plasmodium falciparum renovates the host erythrocyte using mechanisms previously believed to be malaria-specific. This involves proteolytic cleavage of effectors in the endoplasmic reticulum that licences proteins for translocation into the host cell. Recently, it was demonstrated that the related parasite Toxoplasma gondii, responsible for disease in immunocompromised individuals and congenital birth defects, has an analogous pathway with some differences, including proteolytic processing in the Golgi. Here we review the similarities and distinctions in export mechanisms between these and other Apicomplexan parasites to reconcile how this group of pathogens modify their host cells to survive and proliferate.
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70
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Export of malaria proteins requires co-translational processing of the PEXEL motif independent of phosphatidylinositol-3-phosphate binding. Nat Commun 2016; 7:10470. [PMID: 26832821 PMCID: PMC4740378 DOI: 10.1038/ncomms10470] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Accepted: 12/09/2015] [Indexed: 11/08/2022] Open
Abstract
Plasmodium falciparum exports proteins into erythrocytes using the Plasmodium export element (PEXEL) motif, which is cleaved in the endoplasmic reticulum (ER) by plasmepsin V (PMV). A recent study reported that phosphatidylinositol-3-phosphate (PI(3)P) concentrated in the ER binds to PEXEL motifs and is required for export independent of PMV, and that PEXEL motifs are functionally interchangeable with RxLR motifs of oomycete effectors. Here we show that the PEXEL does not bind PI(3)P, and that this lipid is not concentrated in the ER. We find that RxLR motifs cannot mediate export in P. falciparum. Parasites expressing a mutated version of KAHRP, with the PEXEL motif repositioned near the signal sequence, prevented PMV cleavage. This mutant possessed the putative PI(3)P-binding residues but is not exported. Reinstatement of PEXEL to its original location restores processing by PMV and export. These results challenge the PI(3)P hypothesis and provide evidence that PEXEL position is conserved for co-translational processing and export.
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71
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Sappakhaw K, Takasila R, Sittikul P, Wattana-Amorn P, Assavalapsakul W, Boonyalai N. Biochemical characterization of plasmepsin V from Plasmodium vivax Thailand isolates: Substrate specificity and enzyme inhibition. Mol Biochem Parasitol 2016; 204:51-63. [PMID: 26795263 DOI: 10.1016/j.molbiopara.2016.01.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2015] [Revised: 01/05/2016] [Accepted: 01/08/2016] [Indexed: 12/19/2022]
Abstract
Plasmepsin V (PMV) is a Plasmodium aspartic protease responsible for the cleavage of the Plasmodium export element (PEXEL) motif, which is an essential step for export of PEXEL containing proteins and crucial for parasite viability. Here we describe the genetic polymorphism of Plasmodium vivax PMV (PvPMV) Thailand isolates, followed by cloning, expression, purification and characterization of PvPMV-Thai, presenting the pro- and mature-form of PvPMV-Thai. With our refolding and purification method, approximately 1mg of PvPMV-Thai was obtained from 1g of washed inclusion bodies. Unlike PvPMV-Ind and PvPMV-Sal-1, PvPMV-Thai contains a four-amino acid insertion (SVSE) at residues 246-249. We have confirmed that this insertion did not interfere with the catalytic activity as it is located in the long loop (R241-E272) pointing away from the substrate-binding pocket. PvPMV-Thai exhibited similar activity to PfPMV counterparts in which PfEMP2 could be hydrolyzed more efficiently than HRPII. Substrate specificity studies at P1' showed that replacing Ser by Val or Glu of the PfEMP2 peptide markedly reduced the enzyme activity of PvPMV similar to that of PfPMV whereas replacing His by Val or Ser of the HRPII peptide increased the cleavage activity. However, the substitution of amino acids at the P2 position with Glu dramatically reduced the cleavage efficiency by 80% in PvPMV in contrast to 30% in PfPMV, indicating subtle differences around the S2 binding pocket of both PfPMV and PvPMV. Four inhibitors were also evaluated for PvPMV-Thai activity including PMSF, pepstatin A, nelfinavir, and menisporopsin A-a macrocyclic polylactone. We are the first to show that menisporopsin A partially inhibits the PvPMV-Thai activity at high concentration. Taken together, these findings provide insights into recombinant production, substrate specificity and inhibition of PvPMV-Thai.
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Affiliation(s)
- Khomkrit Sappakhaw
- Department of Biochemistry, Special Research Unit for Protein Engineering and Protein Bioinformatics, Faculty of Science, Kasetsart University, 50 Ngam Wong Wan Road, Lat Yao, Chatuchak, Bangkok 10900, Thailand
| | - Ratchaneekorn Takasila
- Department of Biochemistry, Special Research Unit for Protein Engineering and Protein Bioinformatics, Faculty of Science, Kasetsart University, 50 Ngam Wong Wan Road, Lat Yao, Chatuchak, Bangkok 10900, Thailand
| | - Pichamon Sittikul
- Department of Biochemistry, Special Research Unit for Protein Engineering and Protein Bioinformatics, Faculty of Science, Kasetsart University, 50 Ngam Wong Wan Road, Lat Yao, Chatuchak, Bangkok 10900, Thailand
| | - Pakorn Wattana-Amorn
- Center of Excellence for Innovation in Chemistry, Faculty of Science, Kasetsart University, 50 Ngam Wong Wan Road, Lat Yao, Chatuchak, Bangkok 10900, Thailand; Department of Chemistry, Faculty of Science, Kasetsart University, 50 Ngam Wong Wan Road, Lat Yao, Chatuchak, Bangkok 10900, Thailand
| | - Wanchai Assavalapsakul
- Department of Microbiology, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Nonlawat Boonyalai
- Department of Biochemistry, Special Research Unit for Protein Engineering and Protein Bioinformatics, Faculty of Science, Kasetsart University, 50 Ngam Wong Wan Road, Lat Yao, Chatuchak, Bangkok 10900, Thailand; Center of Excellence for Innovation in Chemistry, Faculty of Science, Kasetsart University, 50 Ngam Wong Wan Road, Lat Yao, Chatuchak, Bangkok 10900, Thailand.
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72
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L. M, Soliman ME. The binding landscape of plasmepsin V and the implications for flap dynamics. MOLECULAR BIOSYSTEMS 2016; 12:1457-67. [DOI: 10.1039/c6mb00077k] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Plasmepsin V belongs to the plasmepsin family of aspartic proteases.
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Affiliation(s)
- McGillewie L.
- Molecular Modelling & Drug Design Research Group
- School of Health Sciences
- University of KwaZulu-Natal
- Durban 4001
- South Africa
| | - Mahmoud E. Soliman
- Molecular Modelling & Drug Design Research Group
- School of Health Sciences
- University of KwaZulu-Natal
- Durban 4001
- South Africa
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73
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Malaria Parasite Proteins and Their Role in Alteration of the Structure and Function of Red Blood Cells. ADVANCES IN PARASITOLOGY 2015; 91:1-86. [PMID: 27015947 DOI: 10.1016/bs.apar.2015.09.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Malaria, caused by Plasmodium spp., continues to be a major threat to human health and a significant cause of socioeconomic hardship in many countries. Almost half of the world's population live in malaria-endemic regions and many of them suffer one or more, often life-threatening episodes of malaria every year, the symptoms of which are attributable to replication of the parasite within red blood cells (RBCs). In the case of Plasmodium falciparum, the species responsible for most malaria-related deaths, parasite replication within RBCs is accompanied by striking alterations to the morphological, biochemical and biophysical properties of the host cell that are essential for the parasites' survival. To achieve this, the parasite establishes a unique and extensive protein export network in the infected RBC, dedicating at least 6% of its genome to the process. Understanding the full gamut of proteins involved in this process and the mechanisms by which P. falciparum alters the structure and function of RBCs is important both for a more complete understanding of the pathogenesis of malaria and for development of new therapeutic strategies to prevent or treat this devastating disease. This review focuses on what is currently known about exported parasite proteins, their interactions with the RBC and their likely pathophysiological consequences.
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74
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Coffey MJ, Sleebs BE, Uboldi AD, Garnham A, Franco M, Marino ND, Panas MW, Ferguson DJP, Enciso M, O'Neill MT, Lopaticki S, Stewart RJ, Dewson G, Smyth GK, Smith BJ, Masters SL, Boothroyd JC, Boddey JA, Tonkin CJ. An aspartyl protease defines a novel pathway for export of Toxoplasma proteins into the host cell. eLife 2015; 4:e10809. [PMID: 26576949 PMCID: PMC4764566 DOI: 10.7554/elife.10809] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Accepted: 11/18/2015] [Indexed: 02/03/2023] Open
Abstract
Infection by Toxoplasma gondii leads to massive changes to the host cell. Here, we identify a novel host cell effector export pathway that requires the Golgi-resident aspartyl protease 5 (ASP5). We demonstrate that ASP5 cleaves a highly constrained amino acid motif that has similarity to the PEXEL-motif of Plasmodium parasites. We show that ASP5 matures substrates at both the N- and C-terminal ends of proteins and also controls trafficking of effectors without this motif. Furthermore, ASP5 controls establishment of the nanotubular network and is required for the efficient recruitment of host mitochondria to the vacuole. Assessment of host gene expression reveals that the ASP5-dependent pathway influences thousands of the transcriptional changes that Toxoplasma imparts on its host cell. All these changes result in attenuation of virulence of Δasp5 tachyzoites in vivo. This work characterizes the first identified machinery required for export of Toxoplasma effectors into the infected host cell.
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Affiliation(s)
- Michael J Coffey
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Department of Medical Biology, The University of Melbourne, Melbourne, Australia
| | - Brad E Sleebs
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Department of Medical Biology, The University of Melbourne, Melbourne, Australia
| | - Alessandro D Uboldi
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Department of Medical Biology, The University of Melbourne, Melbourne, Australia
| | - Alexandra Garnham
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Department of Medical Biology, The University of Melbourne, Melbourne, Australia
| | - Magdalena Franco
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, United States
| | - Nicole D Marino
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, United States
| | - Michael W Panas
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, United States
| | - David JP Ferguson
- Nuffield Department of Clinical Laboratory Science, Oxford University, John Radcliffe Hospital, Oxford, United Kingdom
| | - Marta Enciso
- La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Australia
| | - Matthew T O'Neill
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
| | - Sash Lopaticki
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
| | - Rebecca J Stewart
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Department of Medical Biology, The University of Melbourne, Melbourne, Australia
| | - Grant Dewson
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Department of Medical Biology, The University of Melbourne, Melbourne, Australia
| | - Gordon K Smyth
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Department of Mathematics and Statistics, The University of Melbourne, Melbourne, Australia
| | - Brian J Smith
- La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Australia
| | - Seth L Masters
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Department of Medical Biology, The University of Melbourne, Melbourne, Australia
| | - John C Boothroyd
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, United States
| | - Justin A Boddey
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Department of Medical Biology, The University of Melbourne, Melbourne, Australia
| | - Christopher J Tonkin
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Department of Medical Biology, The University of Melbourne, Melbourne, Australia
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75
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Gambini L, Rizzi L, Pedretti A, Taglialatela-Scafati O, Carucci M, Pancotti A, Galli C, Read M, Giurisato E, Romeo S, Russo I. Picomolar Inhibition of Plasmepsin V, an Essential Malaria Protease, Achieved Exploiting the Prime Region. PLoS One 2015; 10:e0142509. [PMID: 26566224 PMCID: PMC4643876 DOI: 10.1371/journal.pone.0142509] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Accepted: 10/22/2015] [Indexed: 01/09/2023] Open
Abstract
Malaria is an infectious disease caused by Plasmodium parasites. It results in an annual death-toll of ~ 600,000. Resistance to all medications currently in use exists, and novel antimalarial drugs are urgently needed. Plasmepsin V (PmV) is an essential Plasmodium protease and a highly promising antimalarial target, which still lacks molecular characterization and drug-like inhibitors. PmV, cleaving the PExEl motif, is the key enzyme for PExEl-secretion, an indispensable parasitic process for virulence and infection. Here, we describe the accessibility of PmV catalytic pockets to inhibitors and propose a novel strategy for PmV inhibition. We also provide molecular and structural data suitable for future drug development. Using high-throughput platforms, we identified a novel scaffold that interferes with PmV in-vitro at picomolar ranges (~ 1,000-fold more active than available compounds). Via systematic replacement of P and P' regions, we assayed the physico-chemical requirements for PmV inhibition, achieving an unprecedented IC50 of ~20 pM. The hydroxyethylamine moiety, the hydrogen acceptor group in P2', the lipophilic groups upstream to P3, the arginine and other possible substitutions in position P3 proved to be critically important elements in achieving potent inhibition. In-silico analyses provided essential QSAR information and model validation. Our inhibitors act ‘on-target’, confirmed by cellular interference of PmV function and biochemical interaction with inhibitors. Our inhibitors are poorly performing against parasite growth, possibly due to poor stability of their peptidic component and trans-membrane permeability. The lowest IC50 for parasite growth inhibition was ~ 15μM. Analysis of inhibitor internalization revealed important pharmacokinetic features for PExEl-based molecules. Our work disclosed novel pursuable drug design strategies for highly efficient PmV inhibition highlighting novel molecular elements necessary for picomolar activity against PmV. All the presented data are discussed in respect to human aspartic proteases and previously reported inhibitors, highlighting differences and proposing new strategies for drug development.
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Affiliation(s)
- Luca Gambini
- Department of Pharmaceutical Sciences, Università degli Studi di Milano, Milan, Italy
| | - Luca Rizzi
- Department of Pharmaceutical Sciences, Università degli Studi di Milano, Milan, Italy
| | - Alessandro Pedretti
- Department of Pharmaceutical Sciences, Università degli Studi di Milano, Milan, Italy
| | - Orazio Taglialatela-Scafati
- Department of Chemistry of Natural Substances, Faculty of Pharmacy, Università di Napoli "Federico II", Naples, Italy
| | - Mario Carucci
- Department of Experimental Medicine and Biochemical Sciences, Università degli Studi di Perugia, Perugia, Italy
| | - Andrea Pancotti
- Department of Pharmaceutical Sciences, Università degli Studi di Milano, Milan, Italy
| | - Corinna Galli
- Department of Pharmaceutical Sciences, Università degli Studi di Milano, Milan, Italy
| | - Martin Read
- Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom
| | - Emanuele Giurisato
- Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom
| | - Sergio Romeo
- Department of Pharmaceutical Sciences, Università degli Studi di Milano, Milan, Italy
| | - Ilaria Russo
- Department of Experimental Medicine and Biochemical Sciences, Università degli Studi di Perugia, Perugia, Italy
- Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom
- * E-mail:
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76
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Abstract
Plasmodium falciparum is the protozoan parasite that causes most malaria-associated morbidity and mortality in humans with over 500,000 deaths annually. The disease symptoms are associated with repeated cycles of invasion and asexual multiplication inside red blood cells of the parasite. Partial, non-sterile immunity to P. falciparum malaria develops only after repeated infections and continuous exposure. The successful evasion of the human immune system relies on the large repertoire of antigenically diverse parasite proteins displayed on the red blood cell surface and on the merozoite membrane where they are exposed to the human immune system. Expression switching of these polymorphic proteins between asexual parasite generations provides an efficient mechanism to adapt to the changing environment in the host and to maintain chronic infection. This chapter discusses antigenic diversity and variation in the malaria parasite and our current understanding of the molecular mechanisms that direct the expression of these proteins.
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Affiliation(s)
- Michaela Petter
- Department of Medicine Royal Melbourne Hospital, Peter Doherty Institute, University of Melbourne, 792 Elizabeth Street, Melbourne, VIC, 3010, Australia.
| | - Michael F Duffy
- Department of Medicine Royal Melbourne Hospital, Peter Doherty Institute, University of Melbourne, 792 Elizabeth Street, Melbourne, VIC, 3010, Australia.
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77
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Hammoudi PM, Jacot D, Mueller C, Di Cristina M, Dogga SK, Marq JB, Romano J, Tosetti N, Dubrot J, Emre Y, Lunghi M, Coppens I, Yamamoto M, Sojka D, Pino P, Soldati-Favre D. Fundamental Roles of the Golgi-Associated Toxoplasma Aspartyl Protease, ASP5, at the Host-Parasite Interface. PLoS Pathog 2015; 11:e1005211. [PMID: 26473595 PMCID: PMC4608785 DOI: 10.1371/journal.ppat.1005211] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2015] [Accepted: 09/16/2015] [Indexed: 11/18/2022] Open
Abstract
Toxoplasma gondii possesses sets of dense granule proteins (GRAs) that either assemble at, or cross the parasitophorous vacuole membrane (PVM) and exhibit motifs resembling the HT/PEXEL previously identified in a repertoire of exported Plasmodium proteins. Within Plasmodium spp., cleavage of the HT/PEXEL motif by the endoplasmic reticulum-resident protease Plasmepsin V precedes trafficking to and export across the PVM of proteins involved in pathogenicity and host cell remodelling. Here, we have functionally characterized the T. gondii aspartyl protease 5 (ASP5), a Golgi-resident protease that is phylogenetically related to Plasmepsin V. We show that deletion of ASP5 causes a significant loss in parasite fitness in vitro and an altered virulence in vivo. Furthermore, we reveal that ASP5 is necessary for the cleavage of GRA16, GRA19 and GRA20 at the PEXEL-like motif. In the absence of ASP5, the intravacuolar nanotubular network disappears and several GRAs fail to localize to the PVM, while GRA16 and GRA24, both known to be targeted to the host cell nucleus, are retained within the vacuolar space. Additionally, hypermigration of dendritic cells and bradyzoite cyst wall formation are impaired, critically impacting on parasite dissemination and persistence. Overall, the absence of ASP5 dramatically compromises the parasite’s ability to modulate host signalling pathways and immune responses. The opportunistic pathogen Toxoplasma gondii infects a large range of nucleated cells where it replicates intracellularly within a parasitophorous vacuole (PV) surrounded by a membrane (PVM). Parasites constitutively secrete dense-granule proteins (GRAs) both into and beyond the PV which participate in remodelling of the PVM, recruitment of host organelles, neutralization of the host cellular defences, and subversion of host cell functioning. In addition, the GRAs critically contribute to cyst wall formation, a process that critically ensures parasite persistence and transmission. To act as effector molecules, some of the GRAs must be translocated across the PVM. Within the related apicomplexan parasite P. falciparum, a repertoire of proteins exported beyond the PVM contain a motif cleaved by a specific protease, Plasmepsin V. Examination of the repertoire of GRAs in T. gondii revealed that some proteins exhibit such export-like motifs suggestive of protease involvement. In this study, we have functionally characterized the related aspartyl protease 5 (TgASP5) in both virulent and persistent T. gondii strains, and have investigated the phenotypic consequences of its deletion in the context of overall parasite biology, its intracellular niche, the infected host cells and the murine model. Our findings revealed fundamental roles of TgASP5 at the host-parasite interface.
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Affiliation(s)
- Pierre-Mehdi Hammoudi
- Department of Microbiology and Molecular Medicine, Centre Médical Universitaire, University of Geneva, Geneva, Switzerland
| | - Damien Jacot
- Department of Microbiology and Molecular Medicine, Centre Médical Universitaire, University of Geneva, Geneva, Switzerland
| | - Christina Mueller
- Department of Microbiology and Molecular Medicine, Centre Médical Universitaire, University of Geneva, Geneva, Switzerland
- Department of Immunoparasitology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Manlio Di Cristina
- Department of Chemistry, Biology and Biotechnology, University of Perugia, Perugia, Italy
| | - Sunil Kumar Dogga
- Department of Microbiology and Molecular Medicine, Centre Médical Universitaire, University of Geneva, Geneva, Switzerland
| | - Jean-Baptiste Marq
- Department of Microbiology and Molecular Medicine, Centre Médical Universitaire, University of Geneva, Geneva, Switzerland
| | - Julia Romano
- Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Nicolò Tosetti
- Department of Microbiology and Molecular Medicine, Centre Médical Universitaire, University of Geneva, Geneva, Switzerland
| | - Juan Dubrot
- Department of Pathology and Immunology, Centre Médical Universitaire, University of Geneva, Geneva, Switzerland
| | - Yalin Emre
- Department of Pathology and Immunology, Centre Médical Universitaire, University of Geneva, Geneva, Switzerland
| | - Matteo Lunghi
- Department of Chemistry, Biology and Biotechnology, University of Perugia, Perugia, Italy
| | - Isabelle Coppens
- Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Masahiro Yamamoto
- Department of Immunoparasitology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Daniel Sojka
- Department of Microbiology and Molecular Medicine, Centre Médical Universitaire, University of Geneva, Geneva, Switzerland
- Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic, České Budějovice, Czech Republic
| | - Paco Pino
- Department of Microbiology and Molecular Medicine, Centre Médical Universitaire, University of Geneva, Geneva, Switzerland
| | - Dominique Soldati-Favre
- Department of Microbiology and Molecular Medicine, Centre Médical Universitaire, University of Geneva, Geneva, Switzerland
- * E-mail:
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78
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Spielmann T, Gilberger TW. Critical Steps in Protein Export of Plasmodium falciparum Blood Stages. Trends Parasitol 2015; 31:514-525. [DOI: 10.1016/j.pt.2015.06.010] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Revised: 06/16/2015] [Accepted: 06/24/2015] [Indexed: 11/29/2022]
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79
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Curt-Varesano A, Braun L, Ranquet C, Hakimi MA, Bougdour A. The aspartyl protease TgASP5 mediates the export of the Toxoplasma GRA16 and GRA24 effectors into host cells. Cell Microbiol 2015; 18:151-67. [PMID: 26270241 DOI: 10.1111/cmi.12498] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Revised: 07/22/2015] [Accepted: 07/27/2015] [Indexed: 12/21/2022]
Abstract
Toxoplasma gondii and Plasmodium species are obligatory intracellular parasites that export proteins into the infected cells in order to interfere with host-signalling pathways, acquire nutrients or evade host defense mechanisms. With regard to export mechanism, a wealth of information in Plasmodium spp. is available, while the mechanisms operating in T. gondii remain uncertain. The recent discovery of exported proteins in T. gondii, mainly represented by dense granule resident proteins, might explain this discrepancy and offers a unique opportunity to study the export mechanism in T. gondii. Here, we report that GRA16 export is mediated by two protein elements present in its N-terminal region. Because the first element contains a putative Plasmodium export element linear motif (RRLAE), we hypothesized that GRA16 export depended on a maturation process involving protein cleavage. Using both N- and C-terminal epitope tags, we provide evidence for protein proteolysis occurring in the N-terminus of GRA16. We show that TgASP5, the T. gondii homolog of Plasmodium plasmepsin V, is essential for GRA16 export and is directly responsible for its maturation in a Plasmodium export element-dependent manner. Interestingly, TgASP5 is also involved in GRA24 export, although the GRA24 maturation mechanism is TgASP5-independent. Our data reveal different modus operandi for protein export, in which TgASP5 should play multiple functions.
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Affiliation(s)
- Aurélie Curt-Varesano
- Laboratoire Adaptation et Pathogénie des Microorganismes, Centre National de la Recherche Scientifique, UMR5163, F-38041, Grenoble, France.,Université Joseph Fourier, F-38000, Grenoble Cedex 09, France
| | - Laurence Braun
- Laboratoire Adaptation et Pathogénie des Microorganismes, Centre National de la Recherche Scientifique, UMR5163, F-38041, Grenoble, France.,Université Joseph Fourier, F-38000, Grenoble Cedex 09, France
| | - Caroline Ranquet
- Bâtiment B - Biologie, BGene Genetics SAS, 2280 rue de la Piscine, 38400, Saint Martin d'Hères, France
| | - Mohamed-Ali Hakimi
- Laboratoire Adaptation et Pathogénie des Microorganismes, Centre National de la Recherche Scientifique, UMR5163, F-38041, Grenoble, France.,Université Joseph Fourier, F-38000, Grenoble Cedex 09, France
| | - Alexandre Bougdour
- Laboratoire Adaptation et Pathogénie des Microorganismes, Centre National de la Recherche Scientifique, UMR5163, F-38041, Grenoble, France.,Université Joseph Fourier, F-38000, Grenoble Cedex 09, France
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80
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McGillewie L, Soliman ME. Flap flexibility amongst plasmepsins I, II, III, IV, and V: Sequence, structural, and molecular dynamics analyses. Proteins 2015; 83:1693-705. [PMID: 26146842 DOI: 10.1002/prot.24855] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2015] [Revised: 06/09/2015] [Accepted: 06/22/2015] [Indexed: 11/05/2022]
Abstract
Herein, for the first time, we comparatively report the opening and closing of apo plasmepsin I - V. Plasmepsins belong the aspartic protease family of enzymes, and are expressed during the various stages of the P. falciparum lifecycle, the species responsible for the most lethal and virulent malaria to infect humans. Plasmepsin I, II, IV and HAP degrade hemoglobin from infected red blood cells, whereas plasmepsin V transport proteins crucial to the survival of the malaria parasite across the endoplasmic reticulum. Flap-structures covering the active site of aspartic proteases (such as HIV protease) are crucial to the conformational flexibility and dynamics of the protein, and ultimately control the binding landscape. The flap-structure in plasmepsins is made up of a flip tip in the N-terminal lying perpendicular to the active site, adjacent to the flexible loop region in the C-terminal. Using molecular dynamics, we propose three parameters to better describe the opening and closing of the flap-structure in apo plasmepsins. Namely, the distance, d1, between the flap tip and the flexible region; the dihedral angle, ϕ, to account for the twisting motion; and the TriCα angle, θ1. Simulations have shown that as the flap-structure twists, the flap and flexible region move apart opening the active site, or move toward each other closing the active site. The data from our study indicate that of all the plasmepsins investigated in the present study, Plm IV and V display the highest conformational flexibility and are more dynamic structures versus Plm I, II, and HAP.
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Affiliation(s)
- Lara McGillewie
- Molecular Modelling & Drug Design Research Group, School of Health Sciences, University of KwaZulu-Natal, Westville, Durban, 4001, South Africa
| | - Mahmoud E Soliman
- Molecular Modelling & Drug Design Research Group, School of Health Sciences, University of KwaZulu-Natal, Westville, Durban, 4001, South Africa
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81
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Structural basis for plasmepsin V inhibition that blocks export of malaria proteins to human erythrocytes. Nat Struct Mol Biol 2015. [PMID: 26214367 DOI: 10.1038/nsmb.3061] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Plasmepsin V, an essential aspartyl protease of malaria parasites, has a key role in the export of effector proteins to parasite-infected erythrocytes. Consequently, it is an important drug target for the two most virulent malaria parasites of humans, Plasmodium falciparum and Plasmodium vivax. We developed a potent inhibitor of plasmepsin V, called WEHI-842, which directly mimics the Plasmodium export element (PEXEL). WEHI-842 inhibits recombinant plasmepsin V with a half-maximal inhibitory concentration of 0.2 nM, efficiently blocks protein export and inhibits parasite growth. We obtained the structure of P. vivax plasmepsin V in complex with WEHI-842 to 2.4-Å resolution, which provides an explanation for the strict requirements for substrate and inhibitor binding. The structure characterizes both a plant-like fold and a malaria-specific helix-turn-helix motif that are likely to be important in cleavage of effector substrates for export.
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82
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Pellé KG, Jiang RHY, Mantel PY, Xiao YP, Hjelmqvist D, Gallego-Lopez GM, O T Lau A, Kang BH, Allred DR, Marti M. Shared elements of host-targeting pathways among apicomplexan parasites of differing lifestyles. Cell Microbiol 2015; 17:1618-39. [PMID: 25996544 DOI: 10.1111/cmi.12460] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Revised: 04/27/2015] [Accepted: 05/14/2015] [Indexed: 11/30/2022]
Abstract
Apicomplexans are a diverse group of obligate parasites occupying different intracellular niches that require modification to meet the needs of the parasite. To efficiently manipulate their environment, apicomplexans translocate numerous parasite proteins into the host cell. Whereas some parasites remain contained within a parasitophorous vacuole membrane (PVM) throughout their developmental cycle, others do not, a difference that affects the machinery needed for protein export. A signal-mediated pathway for protein export into the host cell has been characterized in Plasmodium parasites, which maintain the PVM. Here, we functionally demonstrate an analogous host-targeting pathway involving organellar staging prior to secretion in the related bovine parasite, Babesia bovis, a parasite that destroys the PVM shortly after invasion. Taking into account recent identification of a similar signal-mediated pathway in the coccidian parasite Toxoplasma gondii, we suggest a model in which this conserved pathway has evolved in multiple steps from signal-mediated trafficking to specific secretory organelles for controlled secretion to a complex protein translocation process across the PVM.
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Affiliation(s)
- Karell G Pellé
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, MA, USA
| | - Rays H Y Jiang
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, MA, USA.,The Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Pierre-Yves Mantel
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, MA, USA
| | - Yu-Ping Xiao
- Department of Infectious Diseases and Pathology, University of Florida, Gainesville, FL, USA
| | - Daisy Hjelmqvist
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, MA, USA
| | - Gina M Gallego-Lopez
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, USA
| | - Audrey O T Lau
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, USA
| | - Byung-Ho Kang
- Department of Microbiology and Cell Science, University of Florida, Gainesville, FL, USA
| | - David R Allred
- Department of Infectious Diseases and Pathology, University of Florida, Gainesville, FL, USA.,Genetics Institute, University of Florida, Gainesville, FL, USA
| | - Matthias Marti
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, MA, USA
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83
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Schulze J, Kwiatkowski M, Borner J, Schlüter H, Bruchhaus I, Burmester T, Spielmann T, Pick C. The Plasmodium falciparum exportome contains non-canonical PEXEL/HT proteins. Mol Microbiol 2015; 97:301-14. [PMID: 25850860 DOI: 10.1111/mmi.13024] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/07/2015] [Indexed: 11/29/2022]
Abstract
The pathogenicity of Plasmodium falciparum is partly due to parasite-induced host cell modifications. These modifications are facilitated by exported P. falciparum proteins, collectively referred to as the exportome. Export of several hundred proteins is mediated by the PEXEL/HT, a protease cleavage site. The PEXEL/HT is usually comprised of five amino acids, of which R at position 1, L at position 3 and E, D or Q at position 5 are conserved and important for export. Non-canonical PEXEL/HTs with K or H at position 1 and/or I at position 3 are presently considered non-functional. Here, we show that non-canonical PEXEL/HT proteins are overrepresented in P. falciparum and other Plasmodium species. Furthermore, we show that non-canonical PEXEL/HTs can be cleaved and can promote export in both a REX3 and a GBP reporter, but not in a KAHRP reporter, indicating that non-canonical PEXEL/HTs are functional in concert with a supportive sequence environment. We then selected P. falciparum proteins with a non-canonical PEXEL/HT and show that some of these proteins are exported and that their export depends on non-canonical PEXEL/HTs. We conclude that PEXEL/HT plasticity is higher than appreciated and that non-canonical PEXEL/HT proteins cannot categorically be excluded from Plasmodium exportome predictions.
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Affiliation(s)
- Jana Schulze
- University of Hamburg, Institute of Zoology, Martin-Luther-King-Platz 3, D-20146, Hamburg, Germany
| | - Marcel Kwiatkowski
- Department of Clinical Chemistry, University Medical Center Hamburg-Eppendorf, D-20246, Hamburg, Germany
| | - Janus Borner
- University of Hamburg, Institute of Zoology, Martin-Luther-King-Platz 3, D-20146, Hamburg, Germany
| | - Hartmut Schlüter
- Department of Clinical Chemistry, University Medical Center Hamburg-Eppendorf, D-20246, Hamburg, Germany
| | - Iris Bruchhaus
- Bernhard Nocht Institute for Tropical Medicine, Bernhard-Nocht-Str. 74, D-20359, Hamburg, Germany
| | - Thorsten Burmester
- University of Hamburg, Institute of Zoology, Martin-Luther-King-Platz 3, D-20146, Hamburg, Germany
| | - Tobias Spielmann
- Bernhard Nocht Institute for Tropical Medicine, Bernhard-Nocht-Str. 74, D-20359, Hamburg, Germany
| | - Christian Pick
- University of Hamburg, Institute of Zoology, Martin-Luther-King-Platz 3, D-20146, Hamburg, Germany
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84
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Boonyalai N, Sittikul P, Yuvaniyama J. Plasmodium falciparum Plasmepsin V ( Pf PMV): Insights into recombinant expression, substrate specificity and active site structure. Mol Biochem Parasitol 2015; 201:5-15. [DOI: 10.1016/j.molbiopara.2015.05.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Revised: 04/02/2015] [Accepted: 05/11/2015] [Indexed: 10/23/2022]
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85
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Pesce ER, Blatch GL, Edkins AL. Hsp40 Co-chaperones as Drug Targets: Towards the Development of Specific Inhibitors. TOPICS IN MEDICINAL CHEMISTRY 2015. [DOI: 10.1007/7355_2015_92] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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86
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Vale N, Aguiar L, Gomes P. Antimicrobial peptides: a new class of antimalarial drugs? Front Pharmacol 2014; 5:275. [PMID: 25566072 PMCID: PMC4271771 DOI: 10.3389/fphar.2014.00275] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2014] [Accepted: 11/26/2014] [Indexed: 12/12/2022] Open
Abstract
A range of antimicrobial peptides (AMP) exhibit activity on malaria parasites, Plasmodium spp., in their blood or mosquito stages, or both. These peptides include a diverse array of both natural and synthetic molecules varying greatly in size, charge, hydrophobicity, and secondary structure features. Along with an overview of relevant literature reports regarding AMP that display antiplasmodial activity, this review makes a few considerations about those molecules as a potential new class of antimalarial drugs.
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Affiliation(s)
- Nuno Vale
- Department of Chemistry and Biochemistry, Faculty of Sciences, Centro de Investigação em Química, University of Porto Porto, Portugal
| | - Luísa Aguiar
- Department of Chemistry and Biochemistry, Faculty of Sciences, Centro de Investigação em Química, University of Porto Porto, Portugal
| | - Paula Gomes
- Department of Chemistry and Biochemistry, Faculty of Sciences, Centro de Investigação em Química, University of Porto Porto, Portugal
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87
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Plasmodium falciparum transfected with ultra bright NanoLuc luciferase offers high sensitivity detection for the screening of growth and cellular trafficking inhibitors. PLoS One 2014; 9:e112571. [PMID: 25392998 PMCID: PMC4231029 DOI: 10.1371/journal.pone.0112571] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Accepted: 10/08/2014] [Indexed: 11/19/2022] Open
Abstract
Drug discovery is a key part of malaria control and eradication strategies, and could benefit from sensitive and affordable assays to quantify parasite growth and to help identify the targets of potential anti-malarial compounds. Bioluminescence, achieved through expression of exogenous luciferases, is a powerful tool that has been applied in studies of several aspects of parasite biology and high throughput growth assays. We have expressed the new reporter NanoLuc (Nluc) luciferase in Plasmodium falciparum and showed it is at least 100 times brighter than the commonly used firefly luciferase. Nluc brightness was explored as a means to achieve a growth assay with higher sensitivity and lower cost. In addition we attempted to develop other screening assays that may help interrogate libraries of inhibitory compounds for their mechanism of action. To this end parasites were engineered to express Nluc in the cytoplasm, the parasitophorous vacuole that surrounds the intraerythrocytic parasite or exported to the red blood cell cytosol. As proof-of-concept, these parasites were used to develop functional screening assays for quantifying the effects of Brefeldin A, an inhibitor of protein secretion, and Furosemide, an inhibitor of new permeation pathways used by parasites to acquire plasma nutrients.
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88
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Otto TD, Böhme U, Jackson AP, Hunt M, Franke-Fayard B, Hoeijmakers WAM, Religa AA, Robertson L, Sanders M, Ogun SA, Cunningham D, Erhart A, Billker O, Khan SM, Stunnenberg HG, Langhorne J, Holder AA, Waters AP, Newbold CI, Pain A, Berriman M, Janse CJ. A comprehensive evaluation of rodent malaria parasite genomes and gene expression. BMC Biol 2014; 12:86. [PMID: 25359557 PMCID: PMC4242472 DOI: 10.1186/s12915-014-0086-0] [Citation(s) in RCA: 199] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Accepted: 10/10/2014] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND Rodent malaria parasites (RMP) are used extensively as models of human malaria. Draft RMP genomes have been published for Plasmodium yoelii, P. berghei ANKA (PbA) and P. chabaudi AS (PcAS). Although availability of these genomes made a significant impact on recent malaria research, these genomes were highly fragmented and were annotated with little manual curation. The fragmented nature of the genomes has hampered genome wide analysis of Plasmodium gene regulation and function. RESULTS We have greatly improved the genome assemblies of PbA and PcAS, newly sequenced the virulent parasite P. yoelii YM genome, sequenced additional RMP isolates/lines and have characterized genotypic diversity within RMP species. We have produced RNA-seq data and utilised it to improve gene-model prediction and to provide quantitative, genome-wide, data on gene expression. Comparison of the RMP genomes with the genome of the human malaria parasite P. falciparum and RNA-seq mapping permitted gene annotation at base-pair resolution. Full-length chromosomal annotation permitted a comprehensive classification of all subtelomeric multigene families including the 'Plasmodium interspersed repeat genes' (pir). Phylogenetic classification of the pir family, combined with pir expression patterns, indicates functional diversification within this family. CONCLUSIONS Complete RMP genomes, RNA-seq and genotypic diversity data are excellent and important resources for gene-function and post-genomic analyses and to better interrogate Plasmodium biology. Genotypic diversity between P. chabaudi isolates makes this species an excellent parasite to study genotype-phenotype relationships. The improved classification of multigene families will enhance studies on the role of (variant) exported proteins in virulence and immune evasion/modulation.
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Affiliation(s)
- Thomas D Otto
- />Wellcome Trust Sanger Institute, Hinxton, Cambridge UK
| | - Ulrike Böhme
- />Wellcome Trust Sanger Institute, Hinxton, Cambridge UK
| | - Andrew P Jackson
- />Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool, UK
| | - Martin Hunt
- />Wellcome Trust Sanger Institute, Hinxton, Cambridge UK
| | - Blandine Franke-Fayard
- />Leiden Malaria Research Group, Department of Parasitology, Leiden University Medical Center, Leiden, The Netherlands
| | - Wieteke A M Hoeijmakers
- />Department of Molecular Biology, Science faculty, Radboud Institute for Molecular Life Sciences, Radboud University, Nijmegen, The Netherlands
| | - Agnieszka A Religa
- />Institute of Infection, Immunity & Inflammation, School of Medical, Veterinary & Life Sciences, & Wellcome Centre for Molecular Parasitology, Glasgow Biomedical Research Centre, University of Glasgow, Glasgow, Scotland UK
| | | | - Mandy Sanders
- />Wellcome Trust Sanger Institute, Hinxton, Cambridge UK
| | - Solabomi A Ogun
- />Division of Parasitology, MRC National Institute for Medical Research, Mill Hill, London UK
| | - Deirdre Cunningham
- />Division of Parasitology, MRC National Institute for Medical Research, Mill Hill, London UK
| | - Annette Erhart
- />Unit of Malariology, Institute of Tropical Medicine, Antwerp, Belgium
| | - Oliver Billker
- />Wellcome Trust Sanger Institute, Hinxton, Cambridge UK
| | - Shahid M Khan
- />Leiden Malaria Research Group, Department of Parasitology, Leiden University Medical Center, Leiden, The Netherlands
| | - Hendrik G Stunnenberg
- />Department of Molecular Biology, Science faculty, Radboud Institute for Molecular Life Sciences, Radboud University, Nijmegen, The Netherlands
| | - Jean Langhorne
- />Division of Parasitology, MRC National Institute for Medical Research, Mill Hill, London UK
| | - Anthony A Holder
- />Division of Parasitology, MRC National Institute for Medical Research, Mill Hill, London UK
| | - Andrew P Waters
- />Institute of Infection, Immunity & Inflammation, School of Medical, Veterinary & Life Sciences, & Wellcome Centre for Molecular Parasitology, Glasgow Biomedical Research Centre, University of Glasgow, Glasgow, Scotland UK
| | - Chris I Newbold
- />Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
- />Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Headington, Oxford UK
| | - Arnab Pain
- />Biological and Environmental Sciences and Engineering (BESE) Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Kingdom of Saudi Arabia
| | | | - Chris J Janse
- />Leiden Malaria Research Group, Department of Parasitology, Leiden University Medical Center, Leiden, The Netherlands
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89
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Xiao H, Bryksa BC, Bhaumik P, Gustchina A, Kiso Y, Yao SQ, Wlodawer A, Yada RY. The zymogen of plasmepsin V from Plasmodium falciparum is enzymatically active. Mol Biochem Parasitol 2014; 197:56-63. [PMID: 25447707 PMCID: PMC6310130 DOI: 10.1016/j.molbiopara.2014.10.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Revised: 10/15/2014] [Accepted: 10/16/2014] [Indexed: 10/24/2022]
Abstract
Plasmepsin V, a membrane-bound aspartic protease present in Plasmodium falciparum, is involved in the export of malaria parasite effector proteins into host erythrocytes and therefore is a potential target for antimalarial drug development. The present study reports the bacterial recombinant expression and initial characterization of zymogenic and mature plasmepsin V. A 484-residue truncated form of proplasmepsin (Glu37-Asn521) was fused to a fragment of thioredoxin and expressed as inclusion bodies. Refolding conditions were optimized and zymogen was processed into a mature form via cleavage at the Asn80-Ala81 peptide bond. Mature plasmepsin V exhibited a pH optimum of 5.5-7.0 with Km and kcat of 4.6 μM and 0.24s(-1), respectively, at pH 6.0 using the substrate DABCYL-LNKRLLHETQ-E(EDANS). Furthermore, the prosegment of proplasmepsin V was shown to be nonessential for refolding and inhibition. Unexpectedly, unprocessed proplasmepsin V was enzymatically active with slightly reduced substrate affinity (∼ 2-fold), and similar pH optimum as well as turnover compared to the mature form. Both zymogenic and mature plasmepsin V were partially inhibited by pepstatin A as well as several KNI aspartic protease inhibitors while certain metals strongly inhibited activity. Overall, the present study provides the first report on the nonessentiality of the prosegment for plasmepsin V folding and activity, and therefore, subsequent characterization of its structure-function relationships of both zymogen and mature forms in the development of novel inhibitors with potential antimalarial activities is warranted.
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Affiliation(s)
- Huogen Xiao
- Department of Food Science, University of Guelph, 50 Stone Road East, Guelph, ON, Canada N1G2W1
| | - Brian C Bryksa
- Department of Food Science, University of Guelph, 50 Stone Road East, Guelph, ON, Canada N1G2W1
| | - Prasenjit Bhaumik
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Alla Gustchina
- Protein Structure Section, Macromolecular Crystallography Laboratory, National Cancer Institute, Frederick, MD 21702, USA
| | - Yoshiaki Kiso
- Laboratory of Peptide Science, Nagahama Institute of Bio-Science and Technology, Nagahama, Shiga 526-0829, Japan
| | - Shao Q Yao
- Department of Chemistry, National University of Singapore, 3 Science Drive, Singapore 117543, Singapore
| | - Alexander Wlodawer
- Protein Structure Section, Macromolecular Crystallography Laboratory, National Cancer Institute, Frederick, MD 21702, USA
| | - Rickey Y Yada
- Department of Food Science, University of Guelph, 50 Stone Road East, Guelph, ON, Canada N1G2W1; Faculty of Land and Food Systems, University of British Columbia 248-2357 Main Mall Vancouver, BC V6T 1Z4.
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90
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Sleebs BE, Gazdik M, O'Neill MT, Rajasekaran P, Lopaticki S, Lackovic K, Lowes K, Smith BJ, Cowman AF, Boddey JA. Transition state mimetics of the Plasmodium export element are potent inhibitors of Plasmepsin V from P. falciparum and P. vivax. J Med Chem 2014; 57:7644-62. [PMID: 25167370 DOI: 10.1021/jm500797g] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Following erythrocyte invasion, malaria parasites export a catalogue of remodeling proteins into the infected cell that enable parasite development in the human host. Export is dependent on the activity of the aspartyl protease, plasmepsin V (PMV), which cleaves proteins within the Plasmodium export element (PEXEL; RxL↓xE/Q/D) in the parasite's endoplasmic reticulum. Here, we generated transition state mimetics of the native PEXEL substrate that potently inhibit PMV isolated from Plasmodium falciparum and Plasmodium vivax. Through optimization, we identified that the activity of the mimetics was completely dependent on the presence of P1 Leu and P3 Arg. Treatment of P. falciparum-infected erythrocytes with a set of optimized mimetics impaired PEXEL processing and killed the parasites. The striking effect of the compounds provides a clearer understanding of the accessibility of the PMV active site and reaffirms the enzyme as an attractive target for the design of future antimalarials.
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Affiliation(s)
- Brad E Sleebs
- The Walter and Eliza Hall Institute of Medical Research , 1G Royal Parade, Parkville 3052, Victoria, Australia
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91
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Otto TD, Rayner JC, Böhme U, Pain A, Spottiswoode N, Sanders M, Quail M, Ollomo B, Renaud F, Thomas AW, Prugnolle F, Conway DJ, Newbold C, Berriman M. Genome sequencing of chimpanzee malaria parasites reveals possible pathways of adaptation to human hosts. Nat Commun 2014; 5:4754. [PMID: 25203297 PMCID: PMC4166903 DOI: 10.1038/ncomms5754] [Citation(s) in RCA: 114] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Accepted: 07/18/2014] [Indexed: 01/19/2023] Open
Abstract
Plasmodium falciparum causes most human malaria deaths, having prehistorically evolved from parasites of African Great Apes. Here we explore the genomic basis of P. falciparum adaptation to human hosts by fully sequencing the genome of the closely related chimpanzee parasite species P. reichenowi, and obtaining partial sequence data from a more distantly related chimpanzee parasite (P. gaboni). The close relationship between P. reichenowi and P. falciparum is emphasized by almost complete conservation of genomic synteny, but against this strikingly conserved background we observe major differences at loci involved in erythrocyte invasion. The organization of most virulence-associated multigene families, including the hypervariable var genes, is broadly conserved, but P. falciparum has a smaller subset of rif and stevor genes whose products are expressed on the infected erythrocyte surface. Genome-wide analysis identifies other loci under recent positive selection, but a limited number of changes at the host-parasite interface may have mediated host switching.
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Affiliation(s)
- Thomas D. Otto
- Parasite Genomics, Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Cambridge CB10 1SA, UK
| | - Julian C. Rayner
- Parasite Genomics, Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Cambridge CB10 1SA, UK
| | - Ulrike Böhme
- Parasite Genomics, Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Cambridge CB10 1SA, UK
| | - Arnab Pain
- Parasite Genomics, Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Cambridge CB10 1SA, UK
- Biological and Environmental Sciences and Engineering (BESE) Division, Computational Bioscience Research Center, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia
| | - Natasha Spottiswoode
- National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland 20852, USA
- Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DS, UK
| | - Mandy Sanders
- Parasite Genomics, Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Cambridge CB10 1SA, UK
| | - Michael Quail
- Parasite Genomics, Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Cambridge CB10 1SA, UK
| | - Benjamin Ollomo
- Centre International de Recherches Médicales de Franceville, CIRMF, BP 769 Franceville, Gabon
| | - François Renaud
- Laboratoire MIVEGEC, UMR 5290 CNRS-IRD-UMI-UMII, IRD, BP 64501, 34394 Montpellier, France
| | - Alan W. Thomas
- Biomedical Primate Research Centre, Department of Parasitology, 2280 GH Rijswijk, The Netherlands
| | - Franck Prugnolle
- Centre International de Recherches Médicales de Franceville, CIRMF, BP 769 Franceville, Gabon
- Laboratoire MIVEGEC, UMR 5290 CNRS-IRD-UMI-UMII, IRD, BP 64501, 34394 Montpellier, France
| | - David J. Conway
- Department of Pathogen Molecular Biology, London School of Hygiene & Tropical Medicine, London WC1E 7HT, UK
| | - Chris Newbold
- Parasite Genomics, Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Cambridge CB10 1SA, UK
- Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DS, UK
- These authors contributed equally to this work
| | - Matthew Berriman
- Parasite Genomics, Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Cambridge CB10 1SA, UK
- These authors contributed equally to this work
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92
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Export of virulence proteins by malaria-infected erythrocytes involves remodeling of host actin cytoskeleton. Blood 2014; 124:3459-68. [PMID: 25139348 DOI: 10.1182/blood-2014-06-583054] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Following invasion of human red blood cells (RBCs) by the malaria parasite, Plasmodium falciparum, a remarkable process of remodeling occurs in the host cell mediated by trafficking of several hundred effector proteins to the RBC compartment. The exported virulence protein, P falciparum erythrocyte membrane protein 1 (PfEMP1), is responsible for cytoadherence of infected cells to host endothelial receptors. Maurer clefts are organelles essential for protein trafficking, sorting, and assembly of protein complexes. Here we demonstrate that disruption of PfEMP1 trafficking protein 1 (PfPTP1) function leads to severe alterations in the architecture of Maurer's clefts. Furthermore, 2 major surface antigen families, PfEMP1 and STEVOR, are no longer displayed on the host cell surface leading to ablation of cytoadherence to host receptors. PfPTP1 functions in a large complex of proteins and is required for linking of Maurer's clefts to the host actin cytoskeleton.
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93
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Prajapati SK, Culleton R, Singh OP. Protein trafficking in Plasmodium falciparum-infected red cells and impact of the expansion of exported protein families. Parasitology 2014; 141:1-11. [PMID: 25076418 DOI: 10.1017/s0031182014000948] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
SUMMARY Erythrocytes are extensively remodelled by the malaria parasite following invasion of the cell. Plasmodium falciparum encodes numerous virulence-associated and host-cell remodelling proteins that are trafficked to the cytoplasm, the cell membrane and the surface of the infected erythrocyte. The export of soluble proteins relies on a sequence directing entry into the secretory pathways in addition to an export signal. The export signal consisting of five amino acids is termed the Plasmodium export element (PEXEL) or the vacuole transport signal (VTS). Genome mining studies have revealed that PEXEL/VTS carrying protein families have expanded dramatically in P. falciparum compared with other malaria parasite species, possibly due to lineage-specific expansion linked to the unique requirements of P. falciparum for host-cell remodelling. The functional characterization of such genes and gene families may reveal potential drug targets that could inhibit protein trafficking in infected erythrocytes. This review highlights some of the recent advances and key knowledge gaps in protein trafficking pathways in P. falciparum-infected red cells and speculates on the impact of exported gene families in the trafficking pathway.
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Affiliation(s)
- Surendra K Prajapati
- Molecular Biology Division,National Institute of Malaria Research,New Delhi,India
| | - Richard Culleton
- Malaria Unit,Institute for Tropical Medicine (NEKKEN), Nagasaki University,Nagasaki,Japan
| | - Om P Singh
- Molecular Biology Division,National Institute of Malaria Research,New Delhi,India
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94
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Beck JR, Muralidharan V, Oksman A, Goldberg DE. PTEX component HSP101 mediates export of diverse malaria effectors into host erythrocytes. Nature 2014; 511:592-5. [PMID: 25043010 PMCID: PMC4130291 DOI: 10.1038/nature13574] [Citation(s) in RCA: 197] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Accepted: 06/11/2014] [Indexed: 12/02/2022]
Affiliation(s)
- Josh R Beck
- 1] Department of Molecular Microbiology, Washington University School of Medicine, St Louis, Missouri 63110, USA [2]
| | - Vasant Muralidharan
- 1] Department of Medicine, Washington University School of Medicine, St Louis, Missouri 63110, USA [2] Howard Hughes Medical Institute, Washington University School of Medicine, St Louis, Missouri 63110, USA [3] [4] Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, Georgia 30602, USA
| | - Anna Oksman
- 1] Department of Molecular Microbiology, Washington University School of Medicine, St Louis, Missouri 63110, USA [2] Department of Medicine, Washington University School of Medicine, St Louis, Missouri 63110, USA [3] Howard Hughes Medical Institute, Washington University School of Medicine, St Louis, Missouri 63110, USA
| | - Daniel E Goldberg
- 1] Department of Molecular Microbiology, Washington University School of Medicine, St Louis, Missouri 63110, USA [2] Department of Medicine, Washington University School of Medicine, St Louis, Missouri 63110, USA [3] Howard Hughes Medical Institute, Washington University School of Medicine, St Louis, Missouri 63110, USA
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95
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Elsworth B, Matthews K, Nie CQ, Kalanon M, Charnaud SC, Sanders PR, Chisholm SA, Counihan NA, Shaw PJ, Pino P, Chan JA, Azevedo MF, Rogerson SJ, Beeson JG, Crabb BS, Gilson PR, de Koning-Ward TF. PTEX is an essential nexus for protein export in malaria parasites. Nature 2014; 511:587-91. [DOI: 10.1038/nature13555] [Citation(s) in RCA: 195] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Accepted: 05/30/2014] [Indexed: 11/09/2022]
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96
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Inhibition of Plasmepsin V activity demonstrates its essential role in protein export, PfEMP1 display, and survival of malaria parasites. PLoS Biol 2014; 12:e1001897. [PMID: 24983235 PMCID: PMC4077696 DOI: 10.1371/journal.pbio.1001897] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Accepted: 05/22/2014] [Indexed: 11/19/2022] Open
Abstract
The malaria parasite Plasmodium falciparum exports several hundred proteins into the infected erythrocyte that are involved in cellular remodeling and severe virulence. The export mechanism involves the Plasmodium export element (PEXEL), which is a cleavage site for the parasite protease, Plasmepsin V (PMV). The PMV gene is refractory to deletion, suggesting it is essential, but definitive proof is lacking. Here, we generated a PEXEL-mimetic inhibitor that potently blocks the activity of PMV isolated from P. falciparum and Plasmodium vivax. Assessment of PMV activity in P. falciparum revealed PEXEL cleavage occurs cotranslationaly, similar to signal peptidase. Treatment of P. falciparum-infected erythrocytes with the inhibitor caused dose-dependent inhibition of PEXEL processing as well as protein export, including impaired display of the major virulence adhesin, PfEMP1, on the erythrocyte surface, and cytoadherence. The inhibitor killed parasites at the trophozoite stage and knockdown of PMV enhanced sensitivity to the inhibitor, while overexpression of PMV increased resistance. This provides the first direct evidence that PMV activity is essential for protein export in Plasmodium spp. and for parasite survival in human erythrocytes and validates PMV as an antimalarial drug target.
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97
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Abstract
SUMMARYPlasmodium falciparumdisplays a large and remarkable variety of heat shock protein 40 family members (PfHsp40s). The majority of the PfHsp40s are poorly characterized, and although the functions of some of them have been suggested, their exact mechanism of action is still elusive and their interacting partners and client proteins are unknown. TheP. falciparumheat shock protein 70 family members (PfHsp70s) have been more extensively characterized than the PfHsp40s, with certain members shown to function as molecular chaperones. However, little is known about the PfHsp70-PfHsp40 chaperone partnerships. There is mounting evidence that these chaperones are important not only in protein homoeostasis and cytoprotection, but also in protein trafficking across the parasitophorous vacuole (PV) and into the infected erythrocyte. We propose that certain members of these chaperone families work together to maintain exported proteins in an unfolded state until they reach their final destination. In this review, we critically evaluate what is known and not known about PfHsp40s and PfHsp70s.
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98
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Elsworth B, Crabb BS, Gilson PR. Protein export in malaria parasites: an update. Cell Microbiol 2014; 16:355-63. [PMID: 24418476 DOI: 10.1111/cmi.12261] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Revised: 01/04/2014] [Accepted: 01/06/2014] [Indexed: 11/30/2022]
Abstract
Symptomatic malaria is caused by the infection of human red blood cells (RBCs) with Plasmodium parasites. The RBC is a peculiar environment for parasites to thrive in as they lack many of the normal cellular processes and resources present in other cells. Because of this, Plasmodium spp. have adapted to extensively remodel the host cell through the export of hundreds of proteins that have a range of functions, the best known of which are virulence-associated. Many exported parasite proteins are themselves involved in generating a novel trafficking system in the RBC that further promotes export. In this review we provide an overview of the parasite synthesized export machinery as well as recent developments in how different classes of exported proteins are recognized by this machinery.
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Affiliation(s)
- Brendan Elsworth
- Burnet Institute, 85 Commercial Road, Melbourne, Vic., 3004, Australia; Monash University, Clayton, Vic., Australia
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99
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Bougdour A, Tardieux I, Hakimi MA. Toxoplasmaexports dense granule proteins beyond the vacuole to the host cell nucleus and rewires the host genome expression. Cell Microbiol 2014; 16:334-43. [DOI: 10.1111/cmi.12255] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2013] [Revised: 12/17/2013] [Accepted: 12/18/2013] [Indexed: 12/21/2022]
Affiliation(s)
- Alexandre Bougdour
- CNRS; UMR5163; LAPM; Grenoble 38041 France
- Université Joseph Fourier; Grenoble 38000 France
| | - Isabelle Tardieux
- Institut Cochin; INSERM U1016; CNRS UMR 8104; Université Paris Descartes; Paris 75014 France
| | - Mohamed-Ali Hakimi
- CNRS; UMR5163; LAPM; Grenoble 38041 France
- Université Joseph Fourier; Grenoble 38000 France
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100
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Abstract
Plasmodium falciparum, the causative agent of malaria, completely remodels the infected human erythrocyte to acquire nutrients and to evade the immune system. For this process, the parasite exports more than 10% of all its proteins into the host cell cytosol, including the major virulence factor PfEMP1 (P. falciparum erythrocyte surface protein 1). This unusual protein trafficking system involves long-known parasite-derived membranous structures in the host cell cytosol, called Maurer's clefts. However, the genesis, role, and function of Maurer's clefts remain elusive. Similarly unclear is how proteins are sorted and how they are transported to and from these structures. Recent years have seen a large increase of knowledge but, as yet, no functional model has been established. In this perspective we review the most important findings and conclude with potential possibilities to shed light into the enigma of Maurer's clefts. Understanding the mechanism and function of these structures, as well as their involvement in protein export in P. falciparum, might lead to innovative control strategies and might give us a handle with which to help to eliminate this deadly parasite.
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