Similar Datasets
Project description:The malaria parasite Plasmodium falciparum replicates via schizogony: a fundamentally unusual type of cell cycle involving asynchronous replication of multiple nuclei within the same cytoplasm. It also has one of the most A/T-biased genomes ever sequenced. Here, we present the first comprehensive study of the specification and activation of DNA replication origins during Plasmodium schizogony. Potential replication origins were found to be abundant, with ORC1-binding sites detected every ~800 bp throughout the genome. They had no motif enrichment, but were biased towards areas of higher G/C content. Origin activation was then measured at single-molecule resolution via DNAscent technology, and was much less dense than ORC1-binding sites, with origins activated preferentially in areas of low transcriptional activity. Consistently, replication forks moved slowest through the most highly transcribed genes, suggesting that conflicts between transcription and origin firing inhibit efficient replication, and that P. falciparum has evolved its S-phase to minimise such conflicts.
2023-01-30 | GSE208757 | GEO
Project description:To date, total mRNA analysis throughout intraerythrocytic development of the malaria parasite, Plasmodium falciparum, has only revealed abundance profiles of each gene at a given time. Here, we establish a new methodology in Plasmodium falciparum that enables biosynthetic labeleing and capture of sub-population mRNA. As a proof of principle for this novel method, we examine the mRNA dynamics of early gametocyte commitment.
2015-09-04 | GSE72695 | GEO
Project description:ChIP-seq experiments were performed for the putative telomere repeat-binding factor (PfTRF) in the malaria parasite Plasmodium falciparum strain 3D7. The gene encoding this factor (PF3D7_1209300) was endogenously tagged with either a GFP- or a 3xHA-tag and these transgenic parasite lines were used in ChIP-sequencing experiments. Sequencing of the ChIP and input libraries showed enrichment of PfTRF at all telomere-repeat containing chromosome ends (reference genome Plasmodium falciparum 3D7 from PlasmoDB version 6.1) as well as in all upsB var promoters.In addition,PfTRF was enriched at seven additional, intra-chromosomal sites and called in the PfTRF-HA ChIP-seq only. Plasmodium falciparum 3D7 parasites were generated with -GFP or -3xHA C-terminal tagged TRF (PF3D7_1209300). Nuclei were isolated from formaldehyde cross-linked schizont-stage transgenic parasites and used to prepare chromatin. Chromatin immunoprecipitations were performed using mouse anti-GFP (Roche Diagnostics, #11814460001) or rat anti-HA 3F10 (Roche Diagnostics, #12158167001). Sequencing libraries were prepared according to a Plasmodium-optimized library preparation procedure including KAPA polymerase-mediated PCR amplification.
2016-07-15 | E-GEOD-76537 | biostudies-arrayexpress
Project description:To date, total mRNA analysis throughout intraerythrocytic development of the malaria parasite, Plasmodium falciparum, has only revealed abundance profiles of each gene at a given time. Here, we establish a new methodology in Plasmodium falciparum that enables biosynthetic labeleing and capture of sub-population mRNA. As a proof of principle for this novel method, we examine the mRNA dynamics of early gametocyte commitment. Plasmodium falciparum strains 3D7, E5, and F12 were highly synchronized and, at 36 hours post invasion, incubated with 40um 4-TU for 12 hours followed immediately by Trizol total RNA extraction. Total RNA from each timepoint was then biotinylated via a thiol-group on any transcript that incorporated a thiol-modified UTP. Biotinylated transcripts were then separated from total RNA by Streptavidin magnetic beads resulting in a Labeled sample. Any mRNA that was not bound to the beads resulted in an Unlabeled sample. Every 12 hours, two samples were analyzed by Agilent P. falciparum DNA microarray, Unlabeled and Labeled, resulting in 48 individual DNA microarrays (4 for each sample type).
2015-09-04 | E-GEOD-72695 | biostudies-arrayexpress
Project description:ChIP-seq experiments were performed for the putative Telomere Repeat-binding Zinc finger protein (PfTRZ) in the malaria parasite Plasmodium falciparum strain 3D7. The gene encoding this factor (PF3D7_1209300) was endogenously tagged with either a GFP- or a 3xHA-tag and these transgenic parasite lines were used in ChIP-sequencing experiments. Sequencing of the ChIP and input libraries showed enrichment of PfTRZ at all telomere-repeat containing chromosome ends (reference genome Plasmodium falciparum 3D7 from PlasmoDB version 6.1) as well as in all upsB var promoters.In addition,PfTRZ was enriched at seven additional, intra-chromosomal sites and called in the PfTRZ-HA ChIP-seq only.
2016-07-15 | GSE76537 | GEO
Project description:The mRNA 5â² cap is normally essential for eukaryotic mRNA translation, stabilization and transport and both the cap and eIF4E are important elements of post-transcriptional gene regulation. To further our understanding of mRNA translation in the human malaria parasite Plasmodium falciparum, we have investigated the parasite translation initiation factor eIF4E and its interaction with 5â² capped mRNA. We have purified P. falciparum eIF4E as a recombinant protein and demonstrated that it has canonical mRNA 5â² cap binding activity. We used this protein to purify P. falciparum full-length 5â² capped mRNAs from total parasite RNA. Microarray analysis comparing total and eIF4E-purified 5â² capped mRNAs shows that a subset of 34 features were more than two-fold under-represented in the purified RNA sample, including 19 features representative of nuclear transcripts. The uncapped nuclear transcripts may represent a class of mRNAs targeted for storage and cap removal. Keywords: total RNA vs purified capped mRNA The microarray data were obtained from four hybridizations using RNA from two independent GST-PfeIF4E purifications from separate malaria cultures.
2010-06-10 | E-GEOD-6356 | biostudies-arrayexpress
Project description:Background: Host iron deficiency is protective against severe malaria as the human malaria parasite Plasmodium falciparum depends on free iron from its host to proliferate. Due to the absence of transferrin, ferritin, ferroportin, and a functional heme oxygenase, the parasite’s essential pathways of iron acquisition, storage, export, and detoxification differ from those in humans and may thus be excellent targets for therapeutic development. However, the proteins involved in these processes in P. falciparum remain largely unknown. Experimental design: To identify iron-regulated mechanisms and putative iron transporters in the human malaria parasite Plasmodium falciparum 3D7, we carried out whole-transcriptome profiling using bulk RNA-sequencing. The parasites were cultured either using erythrocytes from a donors with high, medium (healthy) or low iron status (experiment 1); or with red blood cells from another healthy donor in the presence or absence of 0.7 µM hepcidin, a specific ferroportin inhibitor and iron-regulatory hormone (experiment 2). This concentration of hepcidin was reported to reduce binding of ferrous iron to ferroportin by 50% in vitro (39). Samples from three biological replicates each were harvested at the ring and trophozoite stage (6 – 9 and 26 – 29 hours post invasion, hpi) during the second intra-erythrocytic developmental cycle under the conditions specified.
2024-04-08 | E-MTAB-13411 | biostudies-arrayexpress
Project description:During red-blood-cell-stage infection of Plasmodium falciparum, the parasite undergoes repeated rounds of replication, egress, and invasion. Erythrocyte invasion involves specific interactions between host cell receptors and parasite ligands and coordinated expression of genes specific to this step of the life cycle. We show that a parasite-specific bromodomain protein, PfBDP1, binds to chromatin at transcriptional start sites of invasion-related genes and directly controls their expression. Conditional PfBDP1 knockdown causes a dramatic defect in parasite invasion and growth and results in transcriptional downregulation of multiple invasion-related genes at a time point critical for invasion. Conversely, PfBDP1 overexpression enhances expression of these same invasion-related genes. PfBDP1 binds to acetylated histone H3 and a second bromodomain protein, PfBDP2, suggesting a potential mechanism for gene recognition and control. Collectively, these findings show that PfBDP1 critically coordinates expression of invasion genes and indicate that targeting PfBDP1 could be an invaluable tool in malaria eradication. ChIPseq mapping of the genome wide enrichment profile of the P. falciparum bromodomain protein PfBDP1 in two parasite stages and correlation with RNAseq expression data
2016-03-22 | E-GEOD-79135 | biostudies-arrayexpress
Project description:The mRNA 5′ cap is normally essential for eukaryotic mRNA translation, stabilization and transport and both the cap and eIF4E are important elements of post-transcriptional gene regulation. To further our understanding of mRNA translation in the human malaria parasite Plasmodium falciparum, we have investigated the parasite translation initiation factor eIF4E and its interaction with 5′ capped mRNA. We have purified P. falciparum eIF4E as a recombinant protein and demonstrated that it has canonical mRNA 5′ cap binding activity. We used this protein to purify P. falciparum full-length 5′ capped mRNAs from total parasite RNA. Microarray analysis comparing total and eIF4E-purified 5′ capped mRNAs shows that a subset of 34 features were more than two-fold under-represented in the purified RNA sample, including 19 features representative of nuclear transcripts. The uncapped nuclear transcripts may represent a class of mRNAs targeted for storage and cap removal. Keywords: total RNA vs purified capped mRNA
2007-07-07 | GSE6356 | GEO
Project description:The blood-stage infection of the malaria parasite, Plasmodium falciparum, exhibits a 48-hour developmental cycle that culminates in the synchronous release of parasites from red blood cells, triggering 48-hour fever cycles in the host. This cycle could be driven extrinsically by host circadian processes, or by a parasite-intrinsic oscillator. To distinguish between hypotheses, we examined the P. falciparum cycle in an in vitro culture system that lacks extrinsic cues from the host and show that P. falciparum has molecular signatures associated with circadian and cell-cycle oscillators. Each of four strains examined has a unique period, indicating strain-intrinsic period control. Finally, we demonstrate that parasites have low cell-to-cell variance in cycle period, on par with a circadian oscillator. We conclude that an intrinsic oscillator is responsible for Plasmodium’s rhythmic life cycle.
2019-12-10 | GSE141653 | GEO