Plasmodium falciparum
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA245183 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:In summary, we present a systematic in silico screen for the conserved non-coding RNA structures by comparing the P. falciparum genome with seven other malaria species and describe 668 candidate RNA secondary structures. By combining microarray and northern data, we provide evidence for expression of 28 novel ncRNA candidates at the transcript level in the blood stages of P. falciparum, a subset of which show intra-erythrocytic stage-specificity for expression. Few of the expressed novel candidates appear to have similarity to functionally known ncRNAs characterised to-date. The ncRNA candidates that show a narrow phylogenetic distribution, such as the internal var-associated ncRNAs, may be involved in species-specific function. At present, we can not assign specific function to these novel ncRNAs, however, our study highlights the abundance of these novel ncRNA structures in P. falciparum and suggests important roles for these ncRNAs in cellular processes. Although the control of gene expression by mechanisms such as epigenetics, post-transcriptional gene regulation and transcript stability has been recently shown in Plasmodium, all the key cellular players in such types of non-conventional gene regulation in Plasmodium are yet to be identified. Taking cues from the functionally characterized components of the higher eukaryotic non-coding RNA populations, it is tempting to speculate that ncRNAs may, at least in part, be instrumental in gene regulation in P. falciparum. However, in contrast to the higher eukaryotes, the absence of a conventional RNAi pathway and its associated components in malaria suggests that these malaria-specific novel ncRNAs, where functional, must exert their role using novel pathways or mechanisms, possibly unique to malaria. It remains to be determined what fraction of the ncRNAs described here are involved in modulating expression of one or more genes or gene families in malaria and also the precise cellular function for them not only in the blood stages but also in the other life-cycle stages of P. falciparum.
2007-08-23 | E-SGRP-8 | biostudies-arrayexpress
Project description:Plasmodium falciparum Pfs230 and Pfs48/45 are the leading candidates for malaria transmission-blocking vaccines. However, it remains unknown how the two interact and if additional domains in Pfs230 are potential vaccine candidates. Here we report a 3.36 Å resolution cryo-electron microscopy structure of the endogenous Pfs230-Pfs48/45 complex. We show that Pfs48/45 interacts with Pfs230 domains 13 and 14, which are distinct from domains included in current Pfs230 vaccine immunogens. Using a transgenic line with a domain 13 to 14 deletion, we show that these domains are essential for Pfs230 localization on the gamete surface. Nanobodies against these domains inhibit Pfs230-Pfs48/45 complex formation, reduce transmission and structural analyses reveal their binding epitopes. Pfs230 domains 13 and 14 are targets of naturally acquired immunity and when delivered as mRNA-LNP vaccines induced potent immune responses. Our comprehensive structural insights on a core P. falciparum fertilization complex guide the design of novel transmission-blocking vaccine candidates against malaria.
2025-08-08 | PXD060667 | Pride
Project description:Genetic diversity in the next-generation malaria vaccine candidate antigen PfRipr
| PRJNA1204383 | ENA
Project description:During intra-erythrocytic development, late asexually replicating Plasmodium falciparum parasites sequester from peripheral circulation. This facilitates chronic infection and is linked to severe disease and organ-specific pathology including cerebral and placental malaria. Immature gametocytes – sexual stage precursor cells – likewise disappear from circulation. Recent work has demonstrated that these sexual stage parasites are located in the hematopoietic system of the bone marrow before mature gametocytes are released into the blood stream to facilitate mosquito transmission. However, as sequestration occurs only in vivo and not during in vitro culture, the mechanisms by which it is regulated and enacted (particularly by the gametocyte stage) remain poorly understood. We generated the most comprehensive P. falciparum functional gene network to date by integrating global transcriptional data from a large set of asexual and sexual in vitro samples, patient-derived in vivo samples, and a new set of in vitro samples profiling sexual commitment. We defined more than 250 functional modules (clusters) of genes that are co-expressed primarily during the intra-erythrocytic parasite cycle, including 35 during sexual commitment and gametocyte development. Comparing the in vivo and in vitro datasets allowed us, for the first time, to map the time point of asexual parasite sequestration in patients to 22 hours post invasion, confirming previous in vitro observations on the dynamics of host cell modification and cytoadherence. Moreover, we were able to define the properties of gametocyte sequestration, demonstrating the presence of two circulating gametocyte populations: gametocyte rings between 0 and ~30 hours post invasion and mature gametocytes after around 7 days post invasion.
2015-01-13 | GSE64887 | GEO
Project description:The goal of this phase 1/2a sporozoite challenge trial (NCT01883609) was to evaluate novel malaria vaccination regimens of the GSK pre-erythrocytic RTS,S/AS01B vaccine alone and concomitantly same-site administered with the viral vectors ChAd63 & MVA encoding the liver stage antigen construct ME-TRAP. Four vaccine groups were studied and received three vaccinations at a monthly interval. All subjects then underwent controlled human malaria infection (CHMI) 11 weeks after first vaccine administration.
2020-09-01 | GSE103862 | GEO
Project description:Artemisinin and its derivatives exert the potent, antimalarial action, although the mechanisms by which these drugs inhibit the growth of mararia parasites is not fully understood. We used microarrays to detail the global gene expression change in early erythrocytic P. falciparum, and identified molecules that may contribute to the activity of dihydroartemisinin.
2020-11-30 | GSE160666 | GEO
Project description:During intra-erythrocytic development, late asexually replicating Plasmodium falciparum parasites sequester from peripheral circulation. This facilitates chronic infection and is linked to severe disease and organ-specific pathology including cerebral and placental malaria. Immature gametocytes M-bM-^@M-^S sexual stage precursor cells M-bM-^@M-^S likewise disappear from circulation. Recent work has demonstrated that these sexual stage parasites are located in the hematopoietic system of the bone marrow before mature gametocytes are released into the blood stream to facilitate mosquito transmission. However, as sequestration occurs only in vivo and not during in vitro culture, the mechanisms by which it is regulated and enacted (particularly by the gametocyte stage) remain poorly understood. We generated the most comprehensive P. falciparum functional gene network to date by integrating global transcriptional data from a large set of asexual and sexual in vitro samples, patient-derived in vivo samples, and a new set of in vitro samples profiling sexual commitment. We defined more than 250 functional modules (clusters) of genes that are co-expressed primarily during the intra-erythrocytic parasite cycle, including 35 during sexual commitment and gametocyte development. Comparing the in vivo and in vitro datasets allowed us, for the first time, to map the time point of asexual parasite sequestration in patients to 22 hours post invasion, confirming previous in vitro observations on the dynamics of host cell modification and cytoadherence. Moreover, we were able to define the properties of gametocyte sequestration, demonstrating the presence of two circulating gametocyte populations: gametocyte rings between 0 and ~30 hours post invasion and mature gametocytes after around 7 days post invasion. We used 164/TdTom, a transgenic parasite line expressing a red fluorescent protein reporter under a gametocyte-specific promoter to generate schizont samples. Schizonts were subsequently isolated from both the fluorescent and non-fluorescent population by FACS and prepared for microarray analysis. Two biological replicates were produced for both the fluorescent and the non-fluorescent samples.
2015-01-13 | E-GEOD-64887 | biostudies-arrayexpress
Project description:Investigations on the fundamental of malaria parasite biology, such as invasion, growth cycle, metabolism and cell signalling have uncovered a number of potential antimalarial drug targets, including choline kinase, a key enzyme involved in the synthesis of phosphatidylcholine, an important component in parasite membrane compartment. The effect on gene expression of Plasmodium falciparum K1 strain following 72 hours exposure to 2 μM (IC50 concentration) of the choline kinase inhibitor, hexadecyltrimethylammonium bromide (HDTAB) was evaluated by DNA microarray analysis. Genes important in P. falciparum intra-erythrocytic life cycle, such as invasion, cytoadherance and growth were among those affected by at least 2-fold changes in their expression levels compared with non HDTAB-treated control.
2014-02-08 | GSE54775 | GEO
Project description:The molecular basis of coordinated antigen switching enabling chronic infection by human malaria parasites
| PRJNA1282778 | ENA
Project description:Comparative transcriptional analysis of pre-erythrocytic stages
| PRJNA121633 | ENA