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International Journal of Molecular... Jan 2024The development of the ovarian antral follicle is a complex, highly regulated process. Oocytes orchestrate and coordinate the development of mammalian ovarian follicles,...
The development of the ovarian antral follicle is a complex, highly regulated process. Oocytes orchestrate and coordinate the development of mammalian ovarian follicles, and the rate of follicular development is governed by a developmental program intrinsic to the oocyte. Characterizing oocyte signatures during this dynamic process is critical for understanding oocyte maturation and follicular development. Although the transcriptional signature of sheep oocytes matured in vitro and preovulatory oocytes have been previously described, the transcriptional changes of oocytes in antral follicles have not. Here, we used single-cell transcriptomics (SmartSeq2) to characterize sheep oocytes from small, medium, and large antral follicles. We characterized the transcriptomic landscape of sheep oocytes during antral follicle development, identifying unique features in the transcriptional atlas, stage-specific molecular signatures, oocyte-secreted factors, and transcription factor networks. Notably, we identified the specific expression of 222 genes in the LO, 8 and 6 genes that were stage-specific in the MO and SO, respectively. We also elucidated signaling pathways in each antral follicle size that may reflect oocyte quality and in vitro maturation competency. Additionally, we discovered key biological processes that drive the transition from small to large antral follicles, revealing hub genes involved in follicle recruitment and selection. Thus, our work provides a comprehensive characterization of the single-oocyte transcriptome, filling a gap in the mapping of the molecular landscape of sheep oogenesis. We also provide key insights into the transcriptional regulation of the critical sizes of antral follicular development, which is essential for understanding how the oocyte orchestrates follicular development.
Topics: Female; Animals; Sheep; Single-Cell Gene Expression Analysis; Oocytes; Ovarian Follicle; Oogenesis; Ovary; Mammals; Carbamates; Organometallic Compounds
PubMed: 38255985
DOI: 10.3390/ijms25020910 -
Antioxidants (Basel, Switzerland) Dec 2023Vitamin B12 is an essential cofactor involved in the function of two enzymes: cytosolic methionine synthase and mitochondrial methylmalonic-CoA mutase. In our previous...
Vitamin B12 is an essential cofactor involved in the function of two enzymes: cytosolic methionine synthase and mitochondrial methylmalonic-CoA mutase. In our previous studies, caffeine (1,3,7-trimethylxanthine), the most popular bioactivator, was shown to reduce yolk protein (vitellogenin) and fertility in a model. Based on the previous finding that methionine supplementation increases vitellogenesis in , we investigated the role of vitamin B12 in methionine-mediated vitellogenesis during oogenesis in caffeine-ingested animals (CIA). Vitamin B12 supplementation improved vitellogenesis and reduced oxidative stress by decreasing mitochondrial function in CIA. Furthermore, the decreased number of developing oocytes and high levels of reactive oxygen species in oocytes from CIA were recovered with vitamin B12 supplementation through a reduction in mitochondrial stress, which increased vitellogenesis. Taken together, vitamin B12 supplementation can reverse the negative effects of caffeine intake by enhancing methionine-mediated vitellogenesis and oocyte development by reducing mitochondrial stress.
PubMed: 38247478
DOI: 10.3390/antiox13010053 -
ELife Jan 2024The ease of genetic manipulation in using the system has been beneficial in addressing key biological questions. Current modifications of this methodology to...
The ease of genetic manipulation in using the system has been beneficial in addressing key biological questions. Current modifications of this methodology to temporally induce transgene expression require temperature changes or exposure to exogenous compounds, both of which have been shown to have detrimental effects on physiological processes. The recently described auxin-inducible gene expression system (AGES) utilizes the plant hormone auxin to induce transgene expression and is proposed to be the least toxic compound for genetic manipulation, with no obvious effects on development and survival in one wild-type strain. Here, we show that auxin delays larval development in another widely used fly strain, and that short- and long-term auxin exposure in adult induces observable changes in physiology and feeding behavior. We further reveal a dosage response to adult survival upon auxin exposure, and that the recommended auxin concentration for AGES alters feeding activity. Furthermore, auxin-fed male and female flies exhibit a significant decrease in triglyceride levels and display altered transcription of fatty acid metabolism genes. Although fatty acid metabolism is disrupted, auxin does not significantly impact adult female fecundity or progeny survival, suggesting AGES may be an ideal methodology for studying limited biological processes. These results emphasize that experiments using temporal binary systems must be carefully designed and controlled to avoid confounding effects and misinterpretation of results.
Topics: Animals; Drosophila; Drosophila melanogaster; Indoleacetic Acids; Drosophila Proteins; Feeding Behavior; Fatty Acids
PubMed: 38240746
DOI: 10.7554/eLife.91953 -
BMC Medical Genomics Jan 2024Polycystic ovarian syndrome (PCOS) is a common endocrine disorder that affects 6-20% of women of reproductive age. One of the symptoms of PCOS is hyperandrogenism, which...
BACKGROUND
Polycystic ovarian syndrome (PCOS) is a common endocrine disorder that affects 6-20% of women of reproductive age. One of the symptoms of PCOS is hyperandrogenism, which can impair follicular development. This disruption can cause issues with the development of oocytes and the growth of embryos. Although the exact cause of PCOS is not yet fully understood, studying the gene expression pattern of cumulus cells, which play a crucial role in the maturation and quality of oocytes, could help identify the genes associated with oocyte maturation in PCOS women. Through indirect activation of APC/Cdc20, RBX1 enables oocytes to bypass the GV (germinal vesicles) stage and advance to the MII (metaphase II) stage. our other gene is the BAMBI gene which stimulates WNT signaling, that is a crucial pathway for healthy ovarian function. This study aims to explore the expression level of the RBX1 and BAMBI genes between GV and MII oocytes of PCOS and non-PCOS groups.
METHODS
In this experiment, we gathered the cumulus cells of MII (38 cases and 33 control) and GV (38 cases and 33 control) oocytes from women with/without PCOS. Besides, quantitative RT-PCR was used to assess the semi-quantitative expression of BAMBI and RBX1.
RESULTS
According to our research, the expression level of RBX1 and BAMBI in MII and GV cumulus cells of PCOS patients was significantly lower than that in non-PCOS ones.
CONCLUSION
This research raises the possibility of RBX1 and BAMBI involvement in oocyte quality in PCOS women.
Topics: Humans; Female; Polycystic Ovary Syndrome; Oogenesis; Oocytes; Gene Expression; Carrier Proteins; Membrane Proteins
PubMed: 38238750
DOI: 10.1186/s12920-024-01800-2 -
PLoS Neglected Tropical Diseases Jan 2024Anopheles gambiae and its sibling species Anopheles coluzzii are the most efficient vectors of the malaria parasite Plasmodium falciparum. When females of these species...
Anopheles gambiae and its sibling species Anopheles coluzzii are the most efficient vectors of the malaria parasite Plasmodium falciparum. When females of these species feed on an infected human host, oogenesis and parasite development proceed concurrently, but interactions between these processes are not fully understood. Using multiple natural P. falciparum isolates from Burkina Faso, we show that in both vectors, impairing steroid hormone signaling to disrupt oogenesis leads to accelerated oocyst growth and in a manner that appears to depend on both parasite and mosquito genotype. Consistently, we find that egg numbers are negatively linked to oocyst size, a metric for the rate of oocyst development. Oocyst growth rates are also strongly accelerated in females that are in a pre-gravid state, i.e. that fail to develop eggs after an initial blood meal. Overall, these findings advance our understanding of mosquito-parasite interactions that influence P. falciparum development in malaria-endemic regions.
Topics: Animals; Female; Humans; Plasmodium falciparum; Anopheles; Mosquito Vectors; Host-Parasite Interactions; Malaria, Falciparum; Malaria; Oocysts
PubMed: 38206958
DOI: 10.1371/journal.pntd.0011890 -
International Journal of Molecular... Dec 2023Methyl farnesoate (MF), a crucial sesquiterpenoid hormone, plays a pivotal role in the reproduction of female crustaceans, particularly in the vitellogenesis process....
Methyl farnesoate (MF), a crucial sesquiterpenoid hormone, plays a pivotal role in the reproduction of female crustaceans, particularly in the vitellogenesis process. Despite extensive research on its functions, the molecular mechanisms that regulate MF levels during the vitellogenic phase remain largely elusive. This study investigates the roles of microRNAs (miRNAs), significant post-transcriptional regulators of gene expression, in controlling MF levels in the swimming crab . Through bioinformatic analysis, four miRNAs were identified as potential regulators targeting two genes encoding Carboxylesterases (CXEs), which are key enzymes in MF degradation. Dual luciferase reporter assays revealed that and suppress and expression by directly binding to their 3' UTRs. In vivo overexpression of and significantly diminished and levels, consequently elevating hemolymph MF and enhancing expression. Spatiotemporal expression profile analysis showed that these two miRNAs and their targets exhibited generally opposite patterns during ovarian development. These findings demonstrate that and collaboratively modulate MF levels by targeting , thus influencing vitellogenesis in . Additionally, we found that the expression of and were suppressed by MF, constituting a regulatory loop for the regulation of MF levels. The findings contribute novel insights into miRNA-mediated ovarian development regulation in crustaceans and offer valuable information for developing innovative reproduction manipulation techniques for .
Topics: Animals; Female; 3' Untranslated Regions; Brachyura; Carboxylic Ester Hydrolases; Fatty Acids, Unsaturated; MicroRNAs; Vitellogenesis
PubMed: 38203450
DOI: 10.3390/ijms25010279 -
International Journal of Molecular... Dec 2023The oocyte transcriptome follows a tightly controlled dynamic that leads the oocyte to grow and mature. This succession of distinct transcriptional states determines... (Meta-Analysis)
Meta-Analysis Review
The oocyte transcriptome follows a tightly controlled dynamic that leads the oocyte to grow and mature. This succession of distinct transcriptional states determines embryonic development prior to embryonic genome activation. However, these oocyte maternal mRNA regulatory events have yet to be decoded in humans. We reanalyzed human single-oocyte RNA-seq datasets previously published in the literature to decrypt the transcriptomic reshuffles ensuring that the oocyte is fully competent. We applied trajectory analysis (pseudotime) and a meta-analysis and uncovered the fundamental transcriptomic requirements of the oocyte at any moment of oogenesis until reaching the metaphase II stage (MII). We identified a bunch of genes showing significant variation in expression from primordial-to-antral follicle oocyte development and characterized their temporal regulation and their biological relevance. We also revealed the selective regulation of specific transcripts during the germinal vesicle-to-MII transition. Transcripts associated with energy production and mitochondrial functions were extensively downregulated, while those associated with cytoplasmic translation, histone modification, meiotic processes, and RNA processes were conserved. From the genes identified in this study, some appeared as sensitive to environmental factors such as maternal age, polycystic ovary syndrome, cryoconservation, and in vitro maturation. In the future, the atlas of transcriptomic changes described in this study will enable more precise identification of the transcripts responsible for follicular growth and oocyte maturation failures.
Topics: Female; Humans; Pregnancy; Cell Nucleus; Gene Expression Profiling; Oocytes; Oogenesis; Transcriptome
PubMed: 38203203
DOI: 10.3390/ijms25010033 -
EMBO Reports Jan 2024Centrioles are part of centrosomes and cilia, which are microtubule organising centres (MTOC) with diverse functions. Despite their stability, centrioles can disappear...
Centrioles are part of centrosomes and cilia, which are microtubule organising centres (MTOC) with diverse functions. Despite their stability, centrioles can disappear during differentiation, such as in oocytes, but little is known about the regulation of their structural integrity. Our previous research revealed that the pericentriolar material (PCM) that surrounds centrioles and its recruiter, Polo kinase, are downregulated in oogenesis and sufficient for maintaining both centrosome structural integrity and MTOC activity. We now show that the expression of specific components of the centriole cartwheel and wall, including ANA1/CEP295, is essential for maintaining centrosome integrity. We find that Polo kinase requires ANA1 to promote centriole stability in cultured cells and eggs. In addition, ANA1 expression prevents the loss of centrioles observed upon PCM-downregulation. However, the centrioles maintained by overexpressing and tethering ANA1 are inactive, unlike the MTOCs observed upon tethering Polo kinase. These findings demonstrate that several centriole components are needed to maintain centrosome structure. Our study also highlights that centrioles are more dynamic than previously believed, with their structural stability relying on the continuous expression of multiple components.
Topics: Centrioles; Centrosome; Oocytes; Oogenesis; Protein Serine-Threonine Kinases; Animals; Drosophila melanogaster; Drosophila Proteins; Microtubule-Associated Proteins; Humans
PubMed: 38200359
DOI: 10.1038/s44319-023-00020-6 -
Zoological Research Jan 2024Omega-3 polyunsaturated fatty acids (n-3 PUFAs), particularly docosahexaenoic acid (22:6n-3, DHA), play crucial roles in the reproductive health of vertebrates,...
Omega-3 polyunsaturated fatty acids (n-3 PUFAs), particularly docosahexaenoic acid (22:6n-3, DHA), play crucial roles in the reproductive health of vertebrates, including humans. Nevertheless, the underlying mechanism related to this phenomenon remains largely unknown. In this study, we employed two zebrafish genetic models, i.e., mutant as an endogenous DHA-deficient model and (omega-3 desaturase encoding gene) transgenic zebrafish as an endogenous DHA-rich model, to investigate the effects of DHA on oocyte maturation and quality. Results show that the mutants had much lower fecundity and poorer oocyte quality than the wild-type controls, while the zebrafish had higher fecundity and better oocyte quality than wild-type controls. DHA deficiency in embryos led to defects in egg activation, poor microtubule stability, and reduced pregnenolone levels. Further study revealed that DHA promoted pregnenolone synthesis by enhancing transcription of , which encodes the cholesterol side-chain cleavage enzyme, thereby stabilizing microtubule assembly during oogenesis. In turn, the hypothalamic-pituitary-gonadal axis was enhanced by DHA. In conclusion, using two unique genetic models, our findings demonstrate that endogenously synthesized DHA promotes oocyte maturation and quality by promoting pregnenolone production via transcriptional regulation of .
Topics: Animals; Humans; Docosahexaenoic Acids; Zebrafish; Cholesterol Side-Chain Cleavage Enzyme; Oogenesis; Oocytes
PubMed: 38199972
DOI: 10.24272/j.issn.2095-8137.2023.032 -
BMC Genomics Jan 2024Gene-edited mosquitoes lacking a gamma-interferon-inducible lysosomal thiol reductase-like protein, namely (mosGILT) have lower Plasmodium infection, which is linked to...
Gene-edited mosquitoes lacking a gamma-interferon-inducible lysosomal thiol reductase-like protein, namely (mosGILT) have lower Plasmodium infection, which is linked to impaired ovarian development and immune activation. The transcriptome of mosGILT Anopheles gambiae was therefore compared to wild type (WT) mosquitoes by RNA-sequencing to delineate mosGILT-dependent pathways. Compared to WT mosquitoes, mosGILT A. gambiae demonstrated altered expression of genes related to oogenesis, 20-hydroxyecdysone synthesis, as well as immune-related genes. Serendipitously, the zero population growth gene, zpg, an essential regulator of germ cell development was found to be one of the most downregulated genes in mosGILT mosquitoes. These results provide a crucial missing link between two previous studies on the role of zpg and mosGILT in ovarian development. This study further demonstrates that mosGILT has the potential to serve as a target for the biological control of mosquito vectors and to influence the Plasmodium life cycle within the vector.
Topics: Animals; Anopheles; Cell Differentiation; Immunity, Innate; Mosquito Vectors; Germ Cells
PubMed: 38191283
DOI: 10.1186/s12864-023-09887-0