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Cell Reports Nov 2023Plasmodium parasites contribute to one of the highest global infectious disease burdens. To achieve this success, the parasite has evolved a range of specialized...
Plasmodium parasites contribute to one of the highest global infectious disease burdens. To achieve this success, the parasite has evolved a range of specialized subcellular compartments to extensively remodel the host cell for its survival. The information to fully understand these compartments is likely hidden in the so far poorly characterized Plasmodium species spatial proteome. To address this question, we determined the steady-state subcellular location of more than 12,000 parasite proteins across five different species by extensive subcellular fractionation of erythrocytes infected by Plasmodium falciparum, Plasmodium knowlesi, Plasmodium yoelii, Plasmodium berghei, and Plasmodium chabaudi. This comparison of the pan-species spatial proteomes and their expression patterns indicates increasing species-specific proteins associated with the more external compartments, supporting host adaptations and post-transcriptional regulation. The spatial proteome offers comprehensive insight into the different human, simian, and rodent Plasmodium species, establishing a powerful resource for understanding species-specific host adaptation processes in the parasite.
Topics: Humans; Proteomics; Malaria; Proteome; Plasmodium berghei; Erythrocytes
PubMed: 37952150
DOI: 10.1016/j.celrep.2023.113419 -
Nature Communications Sep 2023The Aurora family of kinases orchestrates chromosome segregation and cytokinesis during cell division, with precise spatiotemporal regulation of its catalytic activities...
The Aurora family of kinases orchestrates chromosome segregation and cytokinesis during cell division, with precise spatiotemporal regulation of its catalytic activities by distinct protein scaffolds. Plasmodium spp., the causative agents of malaria, are unicellular eukaryotes with three unique and highly divergent aurora-related kinases (ARK1-3) that are essential for asexual cellular proliferation but lack most canonical scaffolds/activators. Here we investigate the role of ARK2 during sexual proliferation of the rodent malaria Plasmodium berghei, using a combination of super-resolution microscopy, mass spectrometry, and live-cell fluorescence imaging. We find that ARK2 is primarily located at spindle microtubules in the vicinity of kinetochores during both mitosis and meiosis. Interactomic and co-localisation studies reveal several putative ARK2-associated interactors including the microtubule-interacting protein EB1, together with MISFIT and Myosin-K, but no conserved eukaryotic scaffold proteins. Gene function studies indicate that ARK2 and EB1 are complementary in driving endomitotic division and thereby parasite transmission through the mosquito. This discovery underlines the flexibility of molecular networks to rewire and drive unconventional mechanisms of chromosome segregation in the malaria parasite.
Topics: Animals; Chromosome Segregation; Cell Nucleus Division; Plasmodium berghei; Cell Proliferation; Meiosis; Aurora Kinases; Eukaryota
PubMed: 37704606
DOI: 10.1038/s41467-023-41395-3 -
Antimicrobial Agents and Chemotherapy Aug 2023Malaria parasites in the blood stage express a single transmembrane transport protein for the release of the glycolytic end product l-lactate/H from the cell. This...
Malaria parasites in the blood stage express a single transmembrane transport protein for the release of the glycolytic end product l-lactate/H from the cell. This transporter is a member of the strictly microbial formate-nitrite transporter (FNT) family and a novel putative drug target. Small, drug-like FNT inhibitors potently block lactate transport and kill Plasmodium falciparum parasites in culture. The protein structure of Plasmodium falciparum FNT (PfFNT) in complex with the inhibitor has been resolved and confirms its previously predicted binding site and its mode of action as a substrate analog. Here, we investigated the mutational plasticity and essentiality of the PfFNT target on a genetic level, and established its druggability using mouse malaria models. We found that, besides a previously identified PfFNT G107S resistance mutation, selection of parasites at 3 × IC (50% inhibitory concentration) gave rise to two new point mutations affecting inhibitor binding: G21E and V196L. Conditional knockout and mutation of the PfFNT gene showed essentiality in the blood stage, whereas no phenotypic defects in sexual development were observed. PfFNT inhibitors mainly targeted the trophozoite stage and exhibited high potency in P. berghei- and P. falciparum-infected mice. Their activity profiles were comparable to that of artesunate, demonstrating strong potential for the further development of PfFNT inhibitors as novel antimalarials.
Topics: Animals; Mice; Monocarboxylic Acid Transporters; Plasmodium falciparum; Malaria, Falciparum; Antimalarials; Parasites; Lactates; Plasmodium berghei; Protozoan Proteins
PubMed: 37428074
DOI: 10.1128/aac.00356-23 -
Microorganisms Jul 2023Malaria elimination may never succeed without the implementation of transmission-blocking strategies. The transmission of spp. parasites from the human host to the... (Review)
Review
Malaria elimination may never succeed without the implementation of transmission-blocking strategies. The transmission of spp. parasites from the human host to the mosquito vector depends on circulating gametocytes in the peripheral blood of the vertebrate host. Once ingested by the mosquito during blood meals, these sexual forms undergo a series of radical morphological and metabolic changes to survive and progress from the gut to the salivary glands, where they will be waiting to be injected into the vertebrate host. The design of effective transmission-blocking strategies requires a thorough understanding of all the mechanisms that drive the development of gametocytes, gametes, sexual reproduction, and subsequent differentiation within the mosquito. The drastic changes in shape and function throughout its life cycle rely on the tight regulation of stage-specific gene expression. This review outlines the mechanisms involved in sexual stage development in both the human and mosquito vector, and zygote to oocyst differentiation. Functional studies unravel mechanisms employed by to orchestrate the expression of stage-specific functional products required to succeed in its complex life cycle, thus providing us with potential targets for developing new therapeutics. These mechanisms are based on studies conducted with various species, including predominantly and the rodent malaria parasites . However, the great potential of epigenetics, genomics, transcriptomics, proteomics, and functional genetic studies to improve the understanding of malaria as a disease remains partly untapped because of limitations in studies using human malaria parasites and field isolates.
PubMed: 37630530
DOI: 10.3390/microorganisms11081966 -
Scientific Reports Aug 2023Malaria parasites carry out fatty acid synthesis (FAS) in their apicoplast organelle via a bacterially related (type II) enzymatic pathway. In the vertebrate host,...
Malaria parasites carry out fatty acid synthesis (FAS) in their apicoplast organelle via a bacterially related (type II) enzymatic pathway. In the vertebrate host, exoerythrocytic Plasmodium stages rely on FAS, whereas intraerythrocytic stages depend on scavenging FA from their environment. In the mosquito, P. falciparum oocysts express and rely on FAS enzymes for sporozoite formation, but P. yoelii oocysts do not express, nor depend on, FAS enzymes and thus rely on FA scavenging to support sporogony. In P. berghei, FAS enzymes are similarly expendable for sporogony, indicating it conforms to the P. yoelii scenario. We show here that P. berghei, unexpectedly, expresses FAS enzymes throughout oocyst development. These findings indicate that P. berghei can employ FAS alongside FA scavenging to maximise sporogony and transmission, and is more similar to P. falciparum than previously assumed with respect to FA acquisition by the oocyst. The ability of oocysts to switch between FAS and scavenging could be an important factor in the non-competitive relationship of resource exploitation between Plasmodium parasites and their mosquito vectors, which shapes parasite virulence both in the insect and vertebrate.
Topics: Animals; Oocysts; Plasmodium berghei; Mosquito Vectors; Malaria, Falciparum; Anopheles; Fatty Acids; Protozoan Proteins
PubMed: 37543672
DOI: 10.1038/s41598-023-39708-z -
Parasites & Vectors Aug 2023Malaria caused by Plasmodium species is a prominent public health concern worldwide, and the infection of a malarial parasite is transmitted to humans through the saliva...
BACKGROUND
Malaria caused by Plasmodium species is a prominent public health concern worldwide, and the infection of a malarial parasite is transmitted to humans through the saliva of female Anopheles mosquitoes. Plasmodium invasion is a rapid and complex process. A critical step in the blood-stage infection of malarial parasites is the adhesion of merozoites to red blood cells (RBCs), which involves interactions between parasite ligands and receptors. The present study aimed to investigate a previously uncharacterized protein, PbMAP1 (encoded by PBANKA_1425900), which facilitates Plasmodium berghei ANKA (PbANKA) merozoite attachment and invasion via the heparan sulfate receptor.
METHODS
PbMAP1 protein expression was investigated at the asexual blood stage, and its specific binding activity to both heparan sulfate and RBCs was analyzed using western blotting, immunofluorescence, and flow cytometry. Furthermore, a PbMAP1-knockout parasitic strain was established using the double-crossover method to investigate its pathogenicity in mice.
RESULTS
The PbMAP1 protein, primarily localized to the P. berghei membrane at the merozoite stage, is involved in binding to heparan sulfate-like receptor on RBC surface of during merozoite invasion. Furthermore, mice immunized with the PbMAP1 protein or passively immunized with sera from PbMAP1-immunized mice exhibited increased immunity against lethal challenge. The PbMAP1-knockout parasite exhibited reduced pathogenicity.
CONCLUSIONS
PbMAP1 is involved in the binding of P. berghei to heparan sulfate-like receptors on RBC surface during merozoite invasion.
Topics: Humans; Female; Animals; Mice; Plasmodium berghei; Merozoites; Protozoan Proteins; Erythrocytes; Carrier Proteins; Plasmodium falciparum
PubMed: 37563696
DOI: 10.1186/s13071-023-05896-w -
Cell Host & Microbe Sep 2023Malaria remains one of the most devastating infectious diseases. Reverse genetic screens offer a powerful approach to identify genes and molecular processes governing...
Malaria remains one of the most devastating infectious diseases. Reverse genetic screens offer a powerful approach to identify genes and molecular processes governing malaria parasite biology. However, the complex regulation of gene expression and genotype-phenotype associations in the mosquito vector, along with sexual reproduction, have hindered the development of screens in this critical part of the parasite life cycle. To address this, we developed a genetic approach in the rodent parasite Plasmodium berghei that, in combination with barcode sequencing, circumvents the fertilization roadblock and enables screening for gametocyte-expressed genes required for parasite infection of the mosquito Anopheles coluzzii. Our results confirm previous findings, validating our approach for scaling up, and identify genes necessary for mosquito midgut infection, oocyst development, and salivary gland infection. These findings can aid efforts to study malaria transmission biology and to develop interventions for controlling disease transmission.
Topics: Animals; Sporozoites; Mosquito Vectors; Plasmodium berghei; Anopheles
PubMed: 37708854
DOI: 10.1016/j.chom.2023.08.010 -
MBio Oct 2023Cerebral malaria (CM) is a severe neurological complication of infection with acute brain lesions. Genetic variations in both host and parasite have been associated...
Cerebral malaria (CM) is a severe neurological complication of infection with acute brain lesions. Genetic variations in both host and parasite have been associated with susceptibility to CM, but the underlying molecular mechanism remains unclear. Here, we demonstrate that variants of human apolipoprotein E (hApoE) impact the outcome of ANKA (A)-induced experimental cerebral malaria (ECM). Mice carrying the hApoE2 isoform have fewer intracerebral hemorrhages and are more resistant to ECM than mice bearing the hApoE3, hApoE4, or endogenous murine ApoE (mApoE). hApoE2 mice infected with A showed increased splenomegaly and IFN-γ levels in serum but reduced cerebral cell apoptosis that correlated with the survival advantage against ECM. In addition, upregulated expression of genes associated with lipid metabolism and downregulated expression of genes linked to immune responses were observed in the brain tissue of hApoE2 mice relative to ECM-susceptible mice after A infection. Notably, serum cholesterol and the cholesterol content of brain-infiltrating CD8 T cells are significantly higher in infected hApoE2 mice, which might contribute to a significant reduction in the sequestration of brain CD8 T cells. Consistent with the finding that fewer brain lesions occurred in infected hApoE2 mice, fewer behavioral deficits were observed in the hApoE2 mice. Finally, a meta-analysis of publicly available data also showed an increased hApoE2 allele in the malaria-endemic African population, suggesting malaria selection. This study shows that hApoE2 protects mice from ECM through suppression of CD8 T cell activation and migration to the brain and enhanced cholesterol metabolism.IMPORTANCECerebral malaria (CM) is the deadliest complication of malaria infection with an estimated 15%-25% mortality. Even with timely and effective treatment with antimalarial drugs such as quinine and artemisinin derivatives, survivors of CM may suffer long-term cognitive and neurological impairment. Here, we show that human apolipoprotein E variant 2 (hApoE2) protects mice from experimental CM (ECM) via suppression of CD8 T cell activation and infiltration to the brain, enhanced cholesterol metabolism, and increased IFN-γ production, leading to reduced endothelial cell apoptosis, BBB disruption, and ECM symptoms. Our results suggest that hApoE can be an important factor for risk assessment and treatment of CM in humans.
PubMed: 37874152
DOI: 10.1128/mbio.02346-23 -
European Journal of Medicinal Chemistry Oct 2023A novel family of 4-aminoacridine derivatives was obtained by linking this heteroaromatic core to different trans-cinnamic acids. The 4-(N-cinnamoylbutyl)aminoacridines...
A novel family of 4-aminoacridine derivatives was obtained by linking this heteroaromatic core to different trans-cinnamic acids. The 4-(N-cinnamoylbutyl)aminoacridines obtained exhibited in vitro activity in the low- or sub-micromolar range against (i) hepatic stages of Plasmodium berghei, (ii) erythrocytic forms of Plasmodium falciparum, and (iii) early and mature gametocytes of Plasmodium falciparum. The most active compound, having a meta-fluorocinnamoyl group linked to the acridine core, was 20- and 120-fold more potent, respectively, against the hepatic and gametocyte stages of Plasmodium infection than the reference drug, primaquine. Moreover, no cytotoxicity towards mammalian and red blood cells at the concentrations tested was observed for any of the compounds under investigation. These novel conjugates represent promising leads for the development of new multi-target antiplasmodials.
Topics: Animals; Aminacrine; Aminoacridines; Antimalarials; Mammals; Plasmodium berghei; Plasmodium falciparum; Primaquine
PubMed: 37390511
DOI: 10.1016/j.ejmech.2023.115575 -
EMBO Reports Jul 2023Eukaryotic cell adhesion and migration rely on surface adhesins connecting extracellular ligands to the intracellular actin cytoskeleton. Plasmodium sporozoites are...
Eukaryotic cell adhesion and migration rely on surface adhesins connecting extracellular ligands to the intracellular actin cytoskeleton. Plasmodium sporozoites are transmitted by mosquitoes and rely on adhesion and gliding motility to colonize the salivary glands and to reach the liver after transmission. During gliding, the essential sporozoite adhesin TRAP engages actin filaments in the cytoplasm of the parasite, while binding ligands on the substrate through its inserted (I) domain. Crystal structures of TRAP from different Plasmodium species reveal the I domain in closed and open conformations. Here, we probe the importance of these two conformational states by generating parasites expressing versions of TRAP with the I domain stabilized in either the open or closed state with disulfide bonds. Strikingly, both mutations impact sporozoite gliding, mosquito salivary gland entry, and transmission. Absence of gliding in sporozoites expressing the open TRAP I domain can be partially rescued by adding a reducing agent. This suggests that dynamic conformational change is required for ligand binding, gliding motility, and organ invasion and hence sporozoite transmission from mosquito to mammal.
Topics: Animals; Sporozoites; Ligands; Plasmodium; Culicidae; Liver; Protozoan Proteins; Plasmodium berghei; Mammals
PubMed: 37306042
DOI: 10.15252/embr.202357064