PfAP2-G and PfAP2-I ChIP-seq in schizonts
Ontology highlight
ABSTRACT:
ORGANISM(S): Plasmodium falciparum
PROVIDER: GSE120488 | GEO | 2019/02/11
REPOSITORIES: GEO
Similar Datasets
Project description:In the malaria parasite Plasmodium falciparum, the switch from asexual multiplication to sexual differentiation into gametocytes is essential for transmission to mosquitos. One of the key determinants of sexual commitment is the transcription factor PfAP2-G, which has been proposed to orchestrate this crucial cell fate decision by driving expression of gametocyte genes. We show conclusively that PfAP2-G is a transcriptional activator of gametocyte genes and identify the earliest known markers expressed during commitment. Remarkably, we also find that in sexually committed cells, PfAP2-G is associated with the promoters of genes important for red blood cell invasion and activates them through its interactions with a second transcription factor. We thus demonstrate an intriguing transcriptional link between the apparently opposing processes of red blood cell invasion and gametocytogenesis that is coordinated by the master regulator PfAP2-G. This finding has important implications for the development of new anti-malarial drugs that block the invasion of red blood cells by sexually committed cells, thereby preventing parasite transmission.
2019-02-11 | GSE120448 | GEO
Project description:In the malaria parasite Plasmodium falciparum, the switch from asexual multiplication to sexual differentiation into gametocytes is essential for transmission to mosquitos. One of the key determinants of sexual commitment is the transcription factor PfAP2-G, which has been proposed to orchestrate this crucial cell fate decision by driving expression of gametocyte genes. We show conclusively that PfAP2-G is a transcriptional activator of gametocyte genes and identify the earliest known markers expressed during commitment. Remarkably, we also find that in sexually committed cells, PfAP2-G is associated with the promoters of genes important for red blood cell invasion and activates them through its interactions with a second transcription factor. We thus demonstrate an intriguing transcriptional link between the apparently opposing processes of red blood cell invasion and gametocytogenesis that is coordinated by the master regulator PfAP2-G. This finding has important implications for the development of new anti-malarial drugs that block the invasion of red blood cells by sexually committed cells, thereby preventing parasite transmission.
2019-02-08 | GSE121312 | GEO
Project description:In the malaria parasite Plasmodium falciparum, the switch from asexual multiplication to sexual differentiation into gametocytes is essential for transmission to mosquitos. One of the key determinants of sexual commitment is the transcription factor PfAP2-G, which has been proposed to orchestrate this crucial cell fate decision by driving expression of gametocyte genes. We show conclusively that PfAP2-G is a transcriptional activator of gametocyte genes and identify the earliest known markers expressed during commitment. Remarkably, we also find that in sexually committed cells, PfAP2-G is associated with the promoters of genes important for red blood cell invasion and activates them through its interactions with a second transcription factor. We thus demonstrate an intriguing transcriptional link between the apparently opposing processes of red blood cell invasion and gametocytogenesis that is coordinated by the master regulator PfAP2-G. This finding has important implications for the development of new anti-malarial drugs that block the invasion of red blood cells by sexually committed cells, thereby preventing parasite transmission.
2019-02-08 | GSE120990 | 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: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: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:In the malaria parasite Plasmodium falciparum, the switch from asexual multiplication to sexual differentiation into gametocytes is essential for transmission to mosquitos. One of the key determinants of sexual commitment is the transcription factor PfAP2-G, which has been proposed to orchestrate this crucial cell fate decision by driving expression of gametocyte genes. Here we identify for the first time the direct targets of PfAP2-G and demonstrate that it dynamically binds hundreds of sites across the genome. We also identify major differences in PfAP2-G occupancy between gametocytes derived via next-cycle and same-cycle conversion, suggesting significant biological differences between these two pathways. By using a combination of ChIP-seq, transcriptomics, and CRISPR-Cas9, we are able to show definitively that PfAP2-G is a transcriptional activator of early gametocyte genes. Our data implicate PfAP2-G not just as a transcriptional activator of gametocyte genes, but also as a regulator of genes important for red blood cell invasion. Excitingly, we also demonstrate that PfAP2-G interacts with a second transcription factor to regulate transcription. These results shed new light on a critical part of the malaria parasite lifecycle by clarifying the role of PfAP2-G during gametocytogenesis.
2019-07-17 | GSE134268 | GEO
Project description:Gametocytogenesis, the process by which malaria parasites produce sexual forms that can infect mosquitoes, is essential for the transmission of malaria. A transcriptional switch of the pfap2-g gene triggers sexual commitment, but how the complex multi-step process is precisely programed remains largely unknown. Here, by systematic functional screening of a panel of ApiAP2 transcription factors, we identify six new apiAP2 members associated with gametocytogenesis in Plasmodium falciparum. Among these, PfAP2-G5 (PF3D7_1139300) was found to be indispensable for gametocytogenesis. This factor suppresses the transcriptional activity of the pfap2-g gene via binding to both the upstream region and exonic gene body, the latter is linked to the maintenance of local heterochromatin structure, thereby preventing initiation of sexual commitment. Removal of this repressive effect through pfap2-g5 knockout disrupts the asexual replication cycle and promotes sexual commitment accompanied by upregulation of pfap2-g expression. However, the gametocytes produced fail to mature fully. Further analyses show that PfAP2-G5 is essential for gametocyte maturation, and causes the down-regulation of pfap2-g and a set of early gametocyte genes activated by PfAP2-G prior to gametocyte development. Collectively, our findings reveal a regulation cascade of gametocyte production in malaria parasites, and provide a new target for transmission blocking interventions.
2021-08-03 | GSE175931 | GEO
Project description:Gametocytogenesis, the process by which malaria parasites produce sexual forms that can infect mosquitoes, is essential for the transmission of malaria. A transcriptional switch of the pfap2-g gene triggers sexual commitment, but how the complex multi-step process is precisely programed remains largely unknown. Here, by systematic functional screening of a panel of ApiAP2 transcription factors, we identify six new apiAP2 members associated with gametocytogenesis in Plasmodium falciparum. Among these, PfAP2-G5 (PF3D7_1139300) was found to be indispensable for gametocytogenesis. This factor suppresses the transcriptional activity of the pfap2-g gene via binding to both the upstream region and exonic gene body, the latter is linked to the maintenance of local heterochromatin structure, thereby preventing initiation of sexual commitment. Removal of this repressive effect through pfap2-g5 knockout disrupts the asexual replication cycle and promotes sexual commitment accompanied by upregulation of pfap2-g expression. However, the gametocytes produced fail to mature fully. Further analyses show that PfAP2-G5 is essential for gametocyte maturation, and causes the down-regulation of pfap2-g and a set of early gametocyte genes activated by PfAP2-G prior to gametocyte development. Collectively, our findings reveal a regulation cascade of gametocyte production in malaria parasites, and provide a new target for transmission blocking interventions.
2021-08-03 | GSE149772 | GEO
Project description:Malaria is caused by Plasmodium parasites that proliferate through iterative cycles of intra-erythrocytic replication. During each cycle a small number of parasites differentiate into gametocytes, the only forms able to infect the mosquito vector and transmit malaria. Sexual commitment is triggered by activation of AP2-G, the master transcriptional regulator of gametocytogenesis. Heterochromatin protein 1 (HP1)-dependent silencing of ap2-g prevents sexual conversion and secures proliferation. Here, we identify gametocyte development 1 (GDV1) as the first upstream activator of the sexual differentiation pathway in P. falciparum. Induction of GDV1 expression is sufficient to activate AP2-G expression and sexual differentiation. We found that GDV1 targets heterochromatin and triggers HP1 eviction preferentially at ap2-g and other gametocyte-specific genes. We further demonstrate that GDV1-dependent activation of ap2-g is controlled via a gdv1 antisense RNA. In summary, we identify GDV1 as an unprecedented cell fate decision factor that induces sexual differentiation by antagonizing HP1-dependent gene silencing.
2018-05-04 | GSE94901 | GEO