Similar Datasets
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
Project description:In this study we analyzed the spatial and temporal localization of maternal transcripts during oogenesis in Acipenser ruthenus. The occurrence of transcript asymmetry in A. ruthenus has been described at a global level only in matured eggs. However not much is known about the asymmetry during oogenesis. In this study we assessed the temporal establishment of the transcript localization at a global level for A. ruthenus. We were able to determine that there are many transcripts that show temporal variability in the establishment of their localization. We observed an early, predefined and also late pathways for both the vegetally and animally localized transcripts. 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 | GSE211412 | GEO
Project description:The oocyte is a unique cell, from which develops a complex organism comprising of germ layers, tissues and organs. In some vertebrate species it is known that the asymmetrical localization of biomolecules within the oocyte is what drives the spatial differentiation of the daughter cells required for embryogenesis. This asymmetry is first established to produce an animal-vegetal (A-V) axis which reflects the future specification of the ectoderm, mesoderm, and endoderm layers. Several pathways for localization of vegetal maternal transcripts have already been described using a few animal models. However, there is limited information about transcripts that are localized to the animal pole, even though there is accumulating evidence indicating its active establishment. Here, we performed comparative TOMO-Seq analysis on two holoblastic cleavage models: Xenopus laevis and Acipenser ruthenus oocytes during oogenesis. We found that there were many transcripts that have a temporal preference for the establishment of localization. In both models, we observed vegetal transcript gradients that were established during either the early or late oogenesis stages and transcripts that started their localization during the early stages but became more pronounced during the later stages. We found that some animal gradients were already established during the early stages, however the majority were formed during the later stages of oogenesis. Some of these temporally localized transcripts were conserved between the models, while others were species specific. Additionally, temporal de novo transcription and also degradation of transcripts within the oocyte were observed, pointing to an active remodeling of the maternal RNA pool.
| S-EPMC9531136 | biostudies-literature
Project description:The establishment of the dorso-ventral axis is a fundamental process that occurs after fertilization. Dorsal axis specification in frogs starts immediately after fertilization, and depends upon activation of Wnt/?-catenin signaling. The protein kinase CK2? can modulate Wnt/?-catenin signaling and is necessary for dorsal axis specification in Xenopus laevis. Our previous experiments show that CK2? transcripts and protein are animally localized in embryos, overlapping the region where Wnt/?-catenin signaling is activated. Here we determined whether the animal localization of CK2? in the embryo is preceded by its localization in the oocyte. We found that CK2? transcripts were detected from stage I, their levels increased during oogenesis, and were animally localized as early as stage III. CK2? transcripts were translated during oogenesis and CK2? protein was localized to the animal hemisphere of stage VI oocytes. We cloned the CK2? 3'UTR and showed that the 2.8 kb CK2? transcript containing the 3'UTR was enriched during oogenesis. By injecting ectopic mRNAs, we demonstrated that both the coding and 3'UTR regions were necessary for proper CK2? transcript localization. This is the first report showing the involvement of coding and 3'UTR regions in animal transcript localization. Our findings demonstrate the pre-localization of CK2? transcript and thus, CK2? protein, in the oocyte. This may help restrict CK2? expression in preparation for dorsal axis specification.
| S-EPMC4207361 | biostudies-literature
Project description:A method is described which permits the preparation of descrete classes of oocytes of different sizes from all stages of oogenesis in Xenopus laevis. This technique is used in the determination of the content of microtubule protein in oocytes during the course of oogenesis. These experiments show that microtubule protein is present in oocytes of all sizes assayed and that the amount is simply related to the volume of the oocyte. In the largest oocytes microtubule protein constitutes 1% of the soluble protein and this amount does not change on maturation and fertilization. These results show that the changes occurring in the oocyte on maturation which allow the cytoplasm to support microtubule polymerization occur as a result of a modification of the pre-existing microtubule protein, not from protein synthesis de novo. These experiments also indicate that the synthesis of microtubule protein either form 'masked' mRNA or from newly synthesized mRNA plays an insignificant role in microtubule protein synthesis at maturation, ovulation and immediately post-fertilization.
| S-EPMC1165253 | biostudies-other
Project description:Directional transport of specific mRNAs is of primary biological relevance. In Xenopus oocytes, mRNA localization to the vegetal pole is important for germ layer formation and germ cell development. Using a biochemical approach, we identified Xenopus Elr-type proteins, homologs of the Hu/ELAV proteins, as novel components of the vegetal mRNA localization machinery. They bind specifically to the localization elements of several different vegetally localizing Xenopus mRNAs, and they are part of one RNP together with other localization proteins, such as Vg1RBP and XStaufen 1. Blocking Elr-type protein binding by either localization element mutagenesis or antisense morpholino oligonucleotide-mediated masking of their target RNA structures, as well as overexpression of wild type and mutant ElrB proteins, interferes with vegetal localization in Xenopus oocytes.
| S-EPMC2740424 | biostudies-literature
Project description:This SuperSeries is composed of the SubSeries listed below.
2023-11-30 | GSE245320 | GEO
Project description:This SuperSeries is composed of the SubSeries listed below. Refer to individual Series
2016-10-24 | E-GEOD-73431 | biostudies-arrayexpress
Project description:This SuperSeries is composed of the SubSeries listed below.
2019-09-26 | GSE126599 | GEO
Project description:This SuperSeries is composed of the SubSeries listed below.
2016-04-25 | GSE77365 | GEO