Similar Datasets
Project description:Sexual reproduction of Toxoplasma gondii, which is restricted to the small intestine of felids, is sparsely documented in studies involving domestic cats, which also raises ethical concerns. Chromatin modifiers dictate the developmental fate of the parasite during its multistage life cycle, but their targeting to stage-specific cistromes is poorly described. Here we show that AP2XII-1 and AP2XI-2, two transcription factors expressed in tachyzoites, a stage that causes acute toxoplasmosis, silence genes specific to merozoites, a developmental stage critical for sexual commitment and transmission to the next host, including humans. Their conditional and simultaneous depletion leads to a drastic change in the transcriptional program, promoting a complete transition from tachyzoites to merozoites, as revealed by mass spectrometry-based proteomic analyses of the parasites.
2023-09-16 | PXD039400 | Pride
Project description:Sexual reproduction of Toxoplasma gondii, confined to the felid gut, remains largely uncharted owing to ethical concerns regarding the use of cats as model organisms. Chromatin modifiers dictate the developmental fate of the parasite during its multistage life cycle, but their targeting to stage-specific cistromes is poorly described1,2. Here we found that the transcription factors AP2XII-1 and AP2XI-2 operate during the tachyzoite stage, a hallmark of acute toxoplasmosis, to silence genes necessary for merozoites, a developmental stage critical for subsequent sexual commitment and transmission to the next host, including humans. Their conditional and simultaneous depletion leads to a marked change in the transcriptional program, promoting a full transition from tachyzoites to merozoites. These in vitro-cultured pre-gametes have unique protein markers and undergo typical asexual endopolygenic division cycles. In tachyzoites, AP2XII-1 and AP2XI-2 bind DNA as heterodimers at merozoite promoters and recruit MORC and HDAC3 (ref. 1), thereby limiting chromatin accessibility and transcription. Consequently, the commitment to merogony stems from a profound epigenetic rewiring orchestrated by AP2XII-1 and AP2XI-2. Successful production of merozoites in vitro paves the way for future studies on Toxoplasma sexual development without the need for cat infections and holds promise for the development of therapies to prevent parasite transmission.
| S-EPMC10781626 | biostudies-literature
Project description:Here we show that AP2XII-1 and AP2XI-2, two transcription factors expressed in tachyzoites, a stage that causes acute toxoplasmosis, silence genes specific to merozoites, a developmental stage critical for sexual commitment and transmission to the next host, including humans. Their conditional and simultaneous depletion leads to a drastic change in the transcriptional program, promoting a complete transition from tachyzoites to merozoites. Pre-gametes produced in vitro are characterized by specific protein markers and undergo typical asexual endopolygenic division cycles. AP2XII-1 and AP2XI-2 bind DNA as heterodimers at merozoite promoters and recruit the epigenitors MORC and HDAC3, which in turn restrict the accessibility of chromatin to the transcriptional machinery.
2023-09-16 | GSE222832 | GEO
Project description:Here we show that AP2XII-1 and AP2XI-2, two transcription factors expressed in tachyzoites, a stage that causes acute toxoplasmosis, silence genes specific to merozoites, a developmental stage critical for sexual commitment and transmission to the next host, including humans. Their conditional and simultaneous depletion leads to a drastic change in the transcriptional program, promoting a complete transition from tachyzoites to merozoites. Pre-gametes produced in vitro are characterized by specific protein markers and undergo typical asexual endopolygenic division cycles. AP2XII-1 and AP2XI-2 bind DNA as heterodimers at merozoite promoters and recruit the epigenitors MORC and HDAC3, which in turn restrict the accessibility of chromatin to the transcriptional machinery.
2023-09-16 | GSE222819 | GEO
Project description:In vitro production of cat-restricted Toxoplasma pre-sexual stages by epigenetic reprogramming
| PRJNA923617 | ENA
Project description:In vitro production of cat-restricted Toxoplasma pre-sexual stages by epigenetic reprogramming [ATAC-seq]
| PRJNA923619 | ENA
Project description:In vitro production of cat-restricted Toxoplasma pre-sexual stages by epigenetic reprogramming [ChIP-seq]
| PRJNA923616 | ENA
Project description:Cat odors induce rapid, innate and stereotyped defensive behaviors in rats at first exposure, a presumed response to the evolutionary pressures of predation. Bizarrely, rats infected with the brain parasite Toxoplasma gondii approach the cat odors they typically avoid. Since the protozoan Toxoplasma requires the cat to sexually reproduce, this change in host behavior is thought to be a remarkable example of a parasite manipulating a mammalian host for its own benefit. Toxoplasma does not influence host response to non-feline predator odor nor does it alter behavior on olfactory, social, fear or anxiety tests, arguing for specific manipulation in the processing of cat odor. We report that Toxoplasma infection alters neural activity in limbic brain areas necessary for innate defensive behavior in response to cat odor. Moreover, Toxoplasma increases activity in nearby limbic regions of sexual attraction when the rat is exposed to cat urine, compelling evidence that Toxoplasma overwhelms the innate fear response by causing, in its stead, a type of sexual attraction to the normally aversive cat odor.
| S-EPMC3157360 | biostudies-literature
Project description:BACKGROUND:The porcine coccidium Cystoisospora suis is characterized by a complex life-cycle during which asexual multiplication is followed by sexual development with two morphologically distinct cell types, the micro- and macrogametes. Genes related to the sexual stages and cell cycle progression were previously identified in related Apicomplexa. Dynein light chain type 1 and male gamete fusion factor HAP2 are restricted to microgametes. Tyrosine-rich proteins and oocyst wall proteins are a part of the oocyst wall. The Rad51/Dmc1-like protein and Nima-related protein kinases are associated with the cell cycle and fertilization process. Here, the sexual stages of C. suis were characterized in vitro morphologically and for temporal expression changes of the mentioned genes to gain insight into this poorly known phase of coccidian development. METHODS:Sexual stages of C. suis developing in vitro in porcine intestinal epithelial cells were examined by light and electron microscopy. The transcriptional levels of genes related to merozoite multiplication and sexual development were evaluated by quantitative real-time PCR at different time points of cultivation. Transcription levels were compared for parasites in culture supernatants at 6-9 days of cultivation (doc) and intracellular parasites at 6-15 doc. RESULTS:Sexual stage of C. suis was detected during 8-11 doc in vitro. Microgamonts (16.8 ± 0.9 µm) and macrogamonts (16.6 ± 1.1 µm) are very similar in shape and size. Microgametes had a round body (3.5 ± 0.5 µm) and two flagella (11.2 ± 0.5 µm). Macrogametes were spherical with a diameter of 12.1 ± 0.5 µm. Merozoite gene transcription peaked on 10 doc and then declined. Genes related to the sexual stages and cell cycle showed an upregulation with a peak on 13 doc, after which they declined. CONCLUSIONS:The present study linked gene expression changes to the detailed morphological description of C. suis sexual development in vitro, including fertilization, meiosis and oocyst formation in this unique model for coccidian parasites. Following this process at the cellular and molecular level will elucidate details on potential bottlenecks of C. suis development (applicable for coccidian parasites in general) which could be exploited as a novel target for control.
| S-EPMC7079422 | biostudies-literature
Project description:Earlier genetic and inhibitor studies showed that epigenetic regulation of gene expression is critical for malaria parasite survival in multiple life stages and a promising target for new antimalarials. We therefore evaluated the activity of 350 diverse epigenetic inhibitors against multiple stages of Plasmodium falciparum We observed ≥90% inhibition at 10 μM for 28% of compounds against asexual blood stages and early gametocytes, of which a third retained ≥90% inhibition at 1 μM.
| S-EPMC7318029 | biostudies-literature