Changes in heterochromatin distribution during the initial stages of sexual development in Plasmodium falciparum
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ABSTRACT:
ORGANISM(S): Plasmodium falciparum
PROVIDER: GSE252334 | GEO | 2024/10/09
REPOSITORIES: GEO
Similar Datasets
Project description:Differentiation from asexual blood stages to sexual gametocytes is required for transmission of malaria parasites from the human host to mosquitos, where sexual fertilization occurs to complete the lifecycle. Although preventing gametocyte development would block parasite transmission, the molecular mechanisms underlying sexual commitment and gametocyte maturation are still relatively unknown. Previous studies identified an ApiAP2 protein, AP2-G2, which plays a critical role in gametocyte maturation in rodent malaria parasite Plasmodium berghei by acting as the repressor of asexual stage genes in gametocytes. In this work we characterize the P. falciparum orthologue (PF3D7_1408200) of PbAP2-G2 and report that it plays a critical role in maturation of gametocytes. Disruption of pfap2-g2 did not obstruct commitment to sexual development but the majority of parasites were unable to develop normally beyond stage III gametocytes. In asexual stages PfAP2-G2 binds to the promoters of wide variety of genes expressed in diverse range of parasite’s life cycle stages including gametocytes, mosquito lifecycle stages early ring stage genes and genes encoding for proteins involved in egress and invasion. Surprisingly, we also identify binding of PfAP2-G2 in the gene body of almost 3000 genes. We could also show that PfAP2-G2 interacts with chromatin remodeling proteins and another ApiAP2 protein (PF3D7_1139300) whose motif is also overrepresented in the ChIP-seq data. Overall this work suggests that PfAP2-G2 is a transcriptional regulator that regulates genes possibly by recruiting additional transcription factors and chromatin remodeling machinery and plays a critical role in the development of malaria parasites as they transition from the asexual stage to gametocytes.
2021-02-16 | GSE157753 | GEO
Project description:Differentiation from asexual blood stages to sexual gametocytes is required for transmission of malaria parasites from the human to the mosquito host. Preventing gametocyte commitment and development would block parasite transmission, but the underlying molecular mechanisms behind these processes remain poorly understood. Here, we report that the ApiAP2 transcription factor, PfAP2-G2 (PF3D7_1408200) plays a critical role in the maturation of Plasmodium falciparum gametocytes. PfAP2-G2 binds to the promoters of a wide array of genes that are expressed at many stages of the parasite life cycle. Interestingly, we also find binding of PfAP2-G2 within the gene body of almost 3000 genes, which strongly correlates with the location of H3K36me3 and several other histone modifications as well as Heterochromatin Protein 1 (HP1), suggesting that occupancy of PfAP2-G2 in gene bodies may serve as an alternative regulatory mechanism. Disruption of pfap2-g2 does not impact asexual development, parasite multiplication rate, or commitment to sexual development but the majority of sexual parasites are unable to mature beyond stage III gametocytes. The absence of pfap2-g2 leads to overexpression of 28% of the genes bound by PfAP2-G2 and none of the PfAP2-g2 bound are downregulated, suggesting that it is a repressor. We also find that PfAP2-G2 interacts with chromatin remodeling proteins, a microrchidia (MORC) protein, and another ApiAP2 protein (PF3D7_1139300). Overall our data demonstrate that PfAP2-G2 is an important transcription factor that establishes an essential gametocyte maturation program in association with other chromatin-related proteins.
2021-02-01 | GSE160924 | GEO
Project description:Differentiation from asexual blood stages to sexual gametocytes is required for transmission of malaria parasites from the human to the mosquito host. Preventing gametocyte commitment and development would block parasite transmission, but the underlying molecular mechanisms behind these processes remain poorly understood. Here, we report that the ApiAP2 transcription factor, PfAP2-G2 (PF3D7_1408200) plays a critical role in the maturation of Plasmodium falciparum gametocytes. PfAP2-G2 binds to the promoters of a wide array of genes that are expressed at many stages of the parasite life cycle. Interestingly, we also find binding of PfAP2-G2 within the gene body of almost 3000 genes, which strongly correlates with the location of H3K36me3 and several other histone modifications as well as Heterochromatin Protein 1 (HP1), suggesting that occupancy of PfAP2-G2 in gene bodies may serve as an alternative regulatory mechanism. Disruption of pfap2-g2 does not impact asexual development, parasite multiplication rate, or commitment to sexual development but the majority of sexual parasites are unable to mature beyond stage III gametocytes. The absence of pfap2-g2 leads to overexpression of 28% of the genes bound by PfAP2-G2 and none of the PfAP2-g2 bound are downregulated, suggesting that it is a repressor. We also find that PfAP2-G2 interacts with chromatin remodeling proteins, a microrchidia (MORC) protein, and another ApiAP2 protein (PF3D7_1139300). Overall our data demonstrate that PfAP2-G2 is an important transcription factor that establishes an essential gametocyte maturation program in association with other chromatin-related proteins.
2021-02-01 | GSE160923 | GEO
Project description:Gametogenesis is essential for malaria parasite transmission, but the molecular mechanism of this process remains to be refined. Here, we identified a G-protein-coupled receptor 180 (GPR180) that plays a critical role in signal transduction during gametogenesis in Plasmodium. In the rodent parasite P. berghei, PbGPR180 was expressed during asexual and sexual development, with more prominent expression in gametocytes and ookinetes. While PbGPR180 was predominantly localized to cytoplasmic puncta in asexual stages and gametocytes, it became associated with the plasma membrane in female gametes and ookinetes. Knockout of pbgpr180 (Δpbgpr180) had no noticeable effect on asexual development or gametocytogenesis but impaired gamete formation and reduced transmission of the parasites to mosquitoes. Transcriptome analysis of the Δpbgpr180 gametocytes revealed a large proportion of the dysregulated genes with assigned functions in cyclic nucleotide signaling transduction, especially the cGMP-PKG-Ca2+ signaling cascade. Deletion of pbgpr180 resulted in a delay and reduction in cytosolic Ca2+ mobilization during the induction of gametogenesis. In addition, the intracellular cGMP level was significantly reduced in the Δpbgpr180 gametocytes, suggesting that PbGPR180 functions upstream of the cGMP-PKG-Ca2+ signaling pathway. In line with this function, PbGPR180 protein was found to interact with several transmembrane transporter proteins and a small GTPase, Rab6, in activated gametocytes. Allele replacement of pbgpr180 with the P. vivax ortholog pvgpr180 showed equal competence of the transgenic parasite in sexual development, suggesting functional conservation of this gene in Plasmodium spp . These results indicate that GPR180 is involved in cGMP-PKG-Ca2+ signal transduction to regulate gametogenesis in malaria parasites.
2022-04-01 | PXD030837 | Pride
Project description:In the human host, Plasmodium falciparum parasites propagate asexually in erythrocytes causing the symptoms of malaria. However, in every asexual cycle, a small proportion of the parasites commits to sexual differentiation, which is critical for transmission. During a period of about 10 days, the sexually committed parasites either develop into male or female gametocytes. In this study, gametocytes carrying an endogenously GFP tagged version of the female specifically expressed ABCG2 gene were FACS sorted to separate male (GFP low) and female (GFP high) gametocyte populations at different days of development. RNA was subsequently extracted from these populations as well as from asexual parasites as controls and subjected to directional RNAseq. These data reveal the transcriptional differences between asexual parasite stages and developing gametocytes, but also between male and female gametocytes as well as for each sex during the course of differentiation. In particular, male gametocytes undergo distinct transcriptional transitions when comparing the transcriptome between day 4, 6 and 10 of gametocytogenesis. In contrast, female gametocyte transcriptomes are more static during the course of gametocytogenesis and only show minimal variation. This is the first study to longitudinally monitor gene expression in developing male and female gametocytes
2021-07-31 | GSE180985 | 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:The sexual stages are vital phases in malaria parasite transmission and are the targets of various interventions such as transmission blocking vaccines. The molecular mechanisms underlying sexual development, however, remain poorly understood. We report mappping of a determinant previously linked to a male gametocyte development defect in the P. falciparum Dd2 parasite to an 82 kb region on chromosome 12. In order to find a critical gene in this region, we compared gene expression pattern in sexual stage of the parasite between Dd2 and its normal gametocyte-producing ancestor W2 clones. The region contains a sexual stage specific gene (pfmdv 1) that is expressed substantially at a lower level in the Dd2 than in W2 parasite. Disruption of pfmdv 1 results in a dramatic reduction in mature gametocytes, especially male gametocytes, with the majority of sexually committed parasites arrested at stage-I. The pfmdv-1 knockout parasites show an enlarged nucleus, often with separation of the inner and outer nuclear membranes and presence of multi-membrane vesicles in red blood cell cytoplasm. Mosquito infectivity of the knockout parasites is also greatly reduced, but not completely lost, suggesting presence of compensatory mechanisms in the sexual development pathways. Data include Day 8 gametocytes of male defective Dd2 and parental W2 clones of Plasmodium falciparum. The series includes three biological repeats. Keywords: repeat sample
2010-06-10 | E-GEOD-2265 | biostudies-arrayexpress
Project description:Malaria transmission requires the conversion of some asexual parasites into sexual forms termed gametocytes. The initial stages of sexual development, including sexually-committed schizonts and sexual rings, remain poorly characterized, in part because only a subset of parasites undergo sexual development and they are morphologically identical to their asexual counterparts. Here we present a system based on conditional expression of PfAP2-G, the master regulator of sexual conversion, for controlled sexual induction. Induction resulted in ~90% sexual conversion, which enables the characterization of early sexual stages without further purification. Transcriptomic analysis identified the alterations that follow pfap2-g activation, including identification of genes that are down-regulated. We also show that the inducible system enables the characterization of committed stages at the phenotypic level. Altogether, the inducible lines will facilitate the study of the initial stages of sexual development, which is important for the development of new strategies to stop malaria transmission.
2020-06-10 | GSE135005 | GEO
Project description:Malaria transmission requires the conversion of some asexual parasites into sexual forms termed gametocytes. The initial stages of sexual development, including sexually-committed schizonts and sexual rings, remain poorly characterized, in part because only a subset of parasites undergo sexual development and they are morphologically identical to their asexual counterparts. Here we present a system based on conditional expression of PfAP2-G, the master regulator of sexual conversion, for controlled sexual induction. Induction resulted in ~90% sexual conversion, which enables the characterization of early sexual stages without further purification. Transcriptomic analysis identified the alterations that follow pfap2-g activation, including identification of genes that are down-regulated. We also show that the inducible system enables the characterization of committed stages at the phenotypic level. Altogether, the inducible lines will facilitate the study of the initial stages of sexual development, which is important for the development of new strategies to stop malaria transmission.
2020-06-10 | GSE135002 | GEO
Project description:The malaria parasite Plasmodium falciparum employs antigenic variation of the virulence factor P. falciparum erythrocyte membrane protein 1 (PfEMP1) to escape adaptive immune responses during blood infection. Antigenic variation of PfEMP1 occurs through transcriptional switches in the mutually exclusive expression of individual members of the multi-copy var gene family. var genes are located in perinuclear clusters of transcriptionally inactive heterochromatin. Singular var gene activation is linked to locus repositioning into a dedicated zone at the nuclear periphery and deposition of histone 3 lysine 4 di-/trimethylation (H3K4me2/3) and H3K9 acetylation marks in the promoter region. While previous work identified the putative H3K4-specific methyltransferase PfSET10 as an essential enzyme and positive regulator of var gene expression, a recent study reported conflicting data. Here, we used iterative genome editing to engineer a conditional PfSET10 knockout line tailored to study the function of PfSET10 in var gene regulation. We demonstrate that PfSET10 is not required for mutually exclusive var gene expression and switching. We also show that PfSET10 is dispensable not only for asexual parasite proliferation but also for sexual conversion and differentiation of gametocytes. Furthermore, comparative RNA-seq experiments revealed that PfSET10 plays no obvious role in regulating gene expression during asexual parasite development and gametocytogenesis. Interestingly, however, PfSET10 shows different subnuclear localization patterns in asexual and sexual stage parasites and female-specific expression in mature gametocytes. In summary, our work confirms in detail that PfSET10 is not involved in regulating var gene expression and is not required for blood stage parasite viability, at least not when cultured in vitro, thus suggesting PfSET10 may be important for life cycle progression in the mosquito vector or during liver stage development.
2024-06-26 | GSE270631 | GEO