Xenopus laevis
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ABSTRACT:
PROVIDER: PRJNA396491 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Xenopus primordial germ cells (PGCs) are determined by the presence of maternally derived germ plasm. Germ plasm components both protect PGCs from somatic differentiation and begin a unique gene expression program. Segregation of the germline from the endodermal lineage occurs during gastrulation and PGCs subsequently initiate zygotic transcription. However, the gene-networks that operate to both preserve the potential for totipotency and promote germline differentiation are poorly understood. Here, we utilized RNA-sequencing analysis to comprehensively interrogate PGC and neighboring endoderm cell RNAs after lineage segregation. We identified 1,865 transcripts enriched in PGCs compared to endoderm cells. Over 50% of maternal, vegetally-enriched transcripts were enriched in the PGC transcriptome, including sox7. PGC-directed sox7 knockdown and over-expression studies revealed an early requirement for sox7 in proper germ plasm localization, zygotic transcription, and PGC number. We identified oct60 as the most highly expressed and enriched OCT3/4 homologue in PGCs. Lastly, we compared the Xenopus PGC transcriptome with human PGC transcripts and showed that 80% of transcripts are conserved, identifying Xenopus as a relevant model system for understanding the gene-networks necessary for human germline development.
2017-08-01 | GSE102047 | GEO
Project description:Pregnane X receptor (PXR) is generally considered the most important sensor of natural and anthropogenic xenobiotics in vertebrates. In Xenopus, however, PXR plays a role in neural development and it is irresponsive to xenobiotics. We report a first broad-spectrum amphibian xenobiotic receptor, which is an ortholog of the mammalian constitutive androstane receptor (CAR). The low basal activity and pronounced responsiveness to activators such as drugs and steroids displayed by the Xenopus CAR resemble PXR, which both trace back to a common ancestor early in the divergence of land vertebrates. The constitutive activity of CAR emerged first in Sauropsida (reptiles and birds) and it is common to all fully terrestrial land vertebrates (Amniota). This activity can be mimicked by humanizing just two amino acids of the Xenopus CAR. These results demonstrate a remarkable plasticity of CAR which enabled its employment as Xenopus xenosensors. They open way to toxicogenomic and bioaugmentation studies in amphibians, a critically endangered taxon of land vertebrates. Taken together, we provide evidence for a much earlier origin of CAR, for its conservation in tetrapods which exceeds that of PXR, and for its remarkable functional plasticity which enabled its role as a PXR-like xenosensor in Amphibia.
2011-10-11 | GSE28510 | GEO
Project description:microRNAs associated with early neural crest development in Xenopus laevis
| PRJNA429716 | ENA
Project description:Pregnane X receptor (PXR) is generally considered the most important sensor of natural and anthropogenic xenobiotics in vertebrates. In Xenopus, however, PXR plays a role in neural development and it is irresponsive to xenobiotics. We report a first broad-spectrum amphibian xenobiotic receptor, which is an ortholog of the mammalian constitutive androstane receptor (CAR). The low basal activity and pronounced responsiveness to activators such as drugs and steroids displayed by the Xenopus CAR resemble PXR, which both trace back to a common ancestor early in the divergence of land vertebrates. The constitutive activity of CAR emerged first in Sauropsida (reptiles and birds) and it is common to all fully terrestrial land vertebrates (Amniota). This activity can be mimicked by humanizing just two amino acids of the Xenopus CAR. These results demonstrate a remarkable plasticity of CAR which enabled its employment as Xenopus xenosensors. They open way to toxicogenomic and bioaugmentation studies in amphibians, a critically endangered taxon of land vertebrates. Taken together, we provide evidence for a much earlier origin of CAR, for its conservation in tetrapods which exceeds that of PXR, and for its remarkable functional plasticity which enabled its role as a PXR-like xenosensor in Amphibia. We used microarrays to detect global transcriptional changes in Xenopus laevis livers following pregnenolone and artemisinin treatment in order to identify target genes of xlCAR. Arteminisin or pregnenolone were injected intraperitoneally into three frogs on two consecutive days. The control group received in parallel two DMSO injections. All frogs were sacrificed 24 h after the second injection by decapitation, and livers were immediately frozen in liquid nitrogen. After RNA isolation, specimens within the same experimental group were pooled.
2011-10-10 | E-GEOD-28510 | biostudies-arrayexpress
Project description:The molecular mechanisms underlying the commitment of cells to the germ cell lineage and the subsequent formation of germ cells during mammalian development remain poorly understood due to an inability to obtain sufficient amounts of cellular materials to conduct thorough in-vitro analyses. Although primordial germ cells (PGCs) have been generated and isolated from embryonic stem cells (ESCs) in vitro, concurrent expression of several cell surface receptors and transcription factors, at various levels, confounds the identification of these cells. To date, only a few genes that mark the onset of germ cell commitment to the epiblast, including tissue nonspecific alkaline phosphatase (TNAP), Blimp1, Stella, and Fragilis, have been used with some degree of success to detect PGC formation in in-vitro model systems. In light of the current literature, the generation of an unlimited supply of germ cells and gametes from pluripotent stem cells would greatly facilitate studies into reproductive development. To accomplish this, we would need to discover novel markers that are specifically expressed in germ cells. Here we identified four genes that are specifically expressed in male and female germ cells, both in vivo and in vitro, but are not expressed in somatic tissues or ESCs. Expression of these genes therefore allows us to distinguish committed germ cells from undifferentiated pluripotent cell populations, a prerequisite for the successful derivation of germ cells and gametes in vitro. For RNA isolation, PGCs were sorted by FACS, collected by centrifugation, lysed in RLT buffer (QIAGEN), and processed using RNeasy Micro kits with on-column DNase digestion as per the manufacturer's instructions. Integrity of RNA samples was quality-checked using a 2100 Bioanalyzer (Agilent). If possible, 300 ng of total RNA per sample was used as starting material for linear amplification (Illumina TotalPrep RNA amplification kit, Ambion), which involved synthesis of T7-linked double-stranded cDNA and 14 hrs of in-vitro transcription incorporating biotin-labeled nucleotides. Purified and labeled cRNA was then quality-checked on a 2100 Bioanalyser, and hybridized as biological or technical duplicates for 18 hrs onto MouseRef-8 v2 gene expression BeadChips (Illumina), following the manufacturer's instructions. After being washed, the chips were stained with streptavidin-Cy3 (GE Healthcare) and scanned using the iScan reader and accompanying software. 44 samples were analyzed. ESCm: OG2 male Embryonic Stem Cell, +/+ Oct4-GFP ES cells, 1 biological rep 11.5: 11.5 embryonic day PGC (Primordial Germ Cell), 2 biological reps 12.5F: 12.5 embryonic day female PGC (Primordial Germ Cell), 2 biological reps 13.5F: 13.5 embryonic day female PGC (Primordial Germ Cell), 2 biological reps 14.5F: 14.5 embryonic day female PGC (Primordial Germ Cell), 2 biological reps 15.5F: 15.5 embryonic day female PGC (Primordial Germ Cell), 2 biological reps 16.5F: 16.5 embryonic day female PGC (Primordial Germ Cell), 2 biological reps 17.5F: 17.5 embryonic day female PGC (Primordial Germ Cell), 2 biological reps 18.5F: 18.5 embryonic day female PGC (Primordial Germ Cell), 2 biological reps 12.5M: 12.5 embryonic day male PGC (Primordial Germ Cell), 2 biological reps 13.5M: 13.5 embryonic day male PGC (Primordial Germ Cell), 2 biological reps 14.5M: 14.5 embryonic day male PGC (Primordial Germ Cell), 2 biological reps 15.5M: 15.5 embryonic day male PGC (Primordial Germ Cell), 2 biological reps 16.5M: 16.5 embryonic day male PGC (Primordial Germ Cell), 2 biological reps 17.5M: 17.5 embryonic day male PGC (Primordial Germ Cell), 2 biological reps 18.5M: 18.5 embryonic day male PGC (Primordial Germ Cell), 2 biological reps 8M: 8 day after birth male PGC (Primordial Germ Cell), 2 biological reps 10M: 10 day after birth male PGC (Primordial Germ Cell), 2 biological reps 12M: 12 day after birth male PGC (Primordial Germ Cell), 2 biological reps 14M: 14 day after birth male PGC (Primordial Germ Cell), 1 biological rep 16M: 16 day after birth male PGC (Primordial Germ Cell), 2 biological reps 18M: 18 day after birth male PGC (Primordial Germ Cell), 2 biological reps 20M: 20 day after birth male PGC (Primordial Germ Cell), 2 biological reps
2010-11-16 | E-GEOD-23322 | biostudies-arrayexpress
Project description:This dataset includes the files for N-glycoproteome analysis of early and late stage Xenopus laevis embyros, as well as the N-glycome during Xenopus laevis embryogenesis
2019-08-07 | MSV000084180 | MassIVE
Project description:Differential expression analysis of Gcn5 knockdown embryos at early developmental stage 10.5 in Xenopus laevis
| PRJNA309195 | ENA
Project description:In this study we analyzed the spatial and temporal localization of maternal transcripts during oogenesis in Xenopus laevis. The occurrence of transcript asymmetry in X. laevis has been described at a global level only in matured eggs, while the establishment of the asymmetry during oogenesis has been described only for a few transcripts. In this model it was discerned that there exist three pathways (early, intermediate, late) for the establishment of the vegetal gradient, while for the animal gradient not much is known for its production. In this study we assessed the temporal establishment of the transcript localization at a global level for Xenopus laevis. We were able to determine that there are many transcripts that show temporal variability in the establishment of their localization. We observed the previously described early, intermediate (predefined) and also late pathways but found more member transcripts within these groups. We also described, perhaps for the first time, an early, intermediate (predefined) and late pathway for the animal genes as well. Additionally, we showed that some maternal transcripts are dynamic during oogenesis with degradation and de novo production being observed. Our study showed that in additional to spatial orientation to the transcripts, there is a strong temporal factor. The discovery of these new temporal profiles should help to better understand the driving forces during embryogenesis.
2022-08-23 | GSE211415 | GEO