Juvenile hormone (JH) signalling, via its receptor Methoprene-tolerant (Met), controls metamorphosis and reproduction in insects. Met belongs to a superfamily of transcription factors containing the basic Helix Loop Helix (bHLH) and Per Arnt Sim (PAS) domains. Since its discovery in 1986, Met has been characterized in several insect species. However, in spite of the importance as vectors of Chagas disease, our knowledge on the role of Met in JH signalling in Triatominae is limited. In this study, we cloned and sequenced the Dipetalogaster maxima Met transcript (DmaxMet). Molecular modelling was used to build the structure of Met and identify the JH binding site. To further understand the role of the JH receptor during oogenesis, transcript levels were evaluated in two main target organs of JH, fat body and ovary. Functional studies using Met RNAi revealed significant decreases of transcripts for vitellogenin (Vg) and lipophorin (Lp), as well as their receptors. Lp and Vg protein amounts in fat body, as well as Vg in hemolymph were also decreased, and ovarian development was impaired. Overall, these studies provide additional molecular insights on the roles of JH signalling in oogenesis in Triatominae; and therefore are relevant for the epidemiology of Chagas´ disease.
- MeSH
- juvenilní hormony metabolismus MeSH
- methopren * metabolismus MeSH
- oogeneze genetika MeSH
- Triatominae * MeSH
- vitelogeniny MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
- Názvy látek
- juvenilní hormony MeSH
- methopren * MeSH
- vitelogeniny MeSH
Successful reproduction requires an oocyte competent to sustain early embryo development. By the end of oogenesis, the oocyte has entered a transcriptionally silenced state, the mechanisms and significance of which remain poorly understood. Histone H3.3, a histone H3 variant, has unique cell cycle-independent functions in chromatin structure and gene expression. Here, we have characterised the H3.3 chaperone Hira/Cabin1/Ubn1 complex, showing that loss of function of any of these subunits causes early embryogenesis failure in mouse. Transcriptome and nascent RNA analyses revealed that transcription is aberrantly silenced in mutant oocytes. Histone marks, including H3K4me3 and H3K9me3, are reduced and chromatin accessibility is impaired in Hira/Cabin1 mutants. Misregulated genes in mutant oocytes include Zscan4d, a two-cell specific gene involved in zygote genome activation. Overexpression of Zscan4 in the oocyte partially recapitulates the phenotypes of Hira mutants and Zscan4 knockdown in Cabin1 mutant oocytes partially restored their developmental potential, illustrating that temporal and spatial expression of Zscan4 is fine-tuned at the oocyte-to-embryo transition. Thus, the H3.3 chaperone Hira complex has a maternal effect function in oocyte developmental competence and embryogenesis, through modulating chromatin condensation and transcriptional quiescence.
- Klíčová slova
- Competent oocyte, Hira complex, Histone H3.3, Oocyte-to-embryo transition, Zygotic genome activation,
- MeSH
- adaptorové proteiny signální transdukční metabolismus MeSH
- chromatin metabolismus MeSH
- embryonální vývoj genetika MeSH
- genový knockdown MeSH
- histonové chaperony genetika metabolismus MeSH
- histony metabolismus MeSH
- myši inbrední C57BL MeSH
- myši transgenní MeSH
- myši MeSH
- oocyty růst a vývoj metabolismus MeSH
- oogeneze genetika MeSH
- proteiny buněčného cyklu genetika metabolismus MeSH
- signální transdukce genetika MeSH
- transkripční faktory genetika metabolismus MeSH
- zvířata MeSH
- zygota metabolismus MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
- Research Support, U.S. Gov't, Non-P.H.S. MeSH
- Názvy látek
- adaptorové proteiny signální transdukční MeSH
- Cabin1 protein, mouse MeSH Prohlížeč
- chromatin MeSH
- Hira protein, mouse MeSH Prohlížeč
- histonové chaperony MeSH
- histony MeSH
- proteiny buněčného cyklu MeSH
- transkripční faktory MeSH
- Zscan4d protein, mouse MeSH Prohlížeč
miRNAs, ~22nt small RNAs associated with Argonaute (AGO) proteins, are important negative regulators of gene expression in mammalian cells. However, mammalian maternal miRNAs show negligible repressive activity and the miRNA pathway is dispensable for oocytes and maternal-to-zygotic transition. The stoichiometric hypothesis proposed that this is caused by dilution of maternal miRNAs during oocyte growth. As the dilution affects miRNAs but not mRNAs, it creates unfavorable miRNA:mRNA stoichiometry for efficient repression of cognate mRNAs. Here, we report that porcine ssc-miR-205 and bovine bta-miR-10b are exceptional miRNAs, which resist the diluting effect of oocyte growth and can efficiently suppress gene expression. Additional analysis of ssc-miR-205 shows that it has higher stability, reduces expression of endogenous targets, and contributes to the porcine oocyte-to-embryo transition. Consistent with the stoichiometric hypothesis, our results show that the endogenous miRNA pathway in mammalian oocytes is intact and that maternal miRNAs can efficiently suppress gene expression when a favorable miRNA:mRNA stoichiometry is established.
- Klíčová slova
- NanoLuc, miR-10b, miR-205, miRNA, oocyte,
- MeSH
- messenger RNA genetika metabolismus MeSH
- mikro RNA * genetika metabolismus MeSH
- oocyty metabolismus MeSH
- oogeneze genetika MeSH
- prasata MeSH
- skot MeSH
- zvířata MeSH
- zygota metabolismus MeSH
- Check Tag
- skot MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- messenger RNA MeSH
- mikro RNA * MeSH
The most common reason for in vitro fertilization (IVF) cycle cancelation is a lack of quality gametes available for intracytoplasmic sperm injection (ICSI). Here we present the successful fertility treatment of the couple affected by obstructive azoospermia combined with suboptimal response to controlled ovarian stimulation. Since the conventional approach appeared ineffective to overcome both partners' specific problems, the targeted interventions, namely, (1) pharmacological enhancement of sperm motility and (2) polarized light microscopy (PLM)-guided optimization of ICSI time, were applied to rescue the cycle with only immature oocytes and immotile testicular sperm retrieved. The treatment with theophylline aided the selection of viable spermatozoa derived from cryopreserved testicular tissue. When the traditional stimulation protocol failed to produce mature eggs, non-invasive spindle imaging was employed to adjust the sperm injection time to the maturational stage of oocytes extruding a polar body in vitro. The fertilization of 12 late-maturing oocytes yielded 5 zygotes, which all developed into blastocysts. One embryo was transferred into the uterus on day 5 post-fertilization, and another 3 good quality blastocysts were vitrified for later use. The pregnancy resulted in a full-term delivery of a healthy child. This case demonstrates that the individualization beyond the standard IVF protocols should be considered to maximize the chance of poor-prognosis patients to achieve pregnancy with their own gametes.
- Klíčová slova
- IVF add-ons, Oocyte maturity, Polarized light microscopy, Testicular sperm, Theophylline,
- MeSH
- azoospermie epidemiologie terapie MeSH
- ejakulace fyziologie MeSH
- fertilizace in vitro trendy MeSH
- indukce ovulace MeSH
- intracytoplazmatické injekce spermie MeSH
- kryoprezervace * MeSH
- lidé MeSH
- motilita spermií genetika MeSH
- narození živého dítěte epidemiologie MeSH
- oocyty růst a vývoj MeSH
- oogeneze genetika MeSH
- spermie patologie transplantace MeSH
- těhotenství MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- kazuistiky MeSH
Protein syntheses at appropriate timings are important for promoting diverse biological processes and are controlled at the levels of transcription and translation. Pou5f1/Oct4 is a transcription factor that is essential for vertebrate embryonic development. However, the precise timings when the mRNA and protein of Pou5f1/Oct4 are expressed during oogenesis and early stages of embryogenesis remain unclear. We analyzed the expression patterns of mRNA and protein of Pou5f1/Oct4 in mouse oocytes and embryos by using a highly sensitive in situ hybridization method and a monoclonal antibody specific to Pou5f1/Oct4, respectively. Pou5f1/Oct4 mRNA was detected in growing oocytes from the primary follicle stage to the fully grown GV stage during oogenesis. In contrast, Pou5f1/Oct4 protein was undetectable during oogenesis, oocyte maturation and the first cleavage stage but subsequently became detectable in the nuclei of early 2-cell-stage embryos. Pou5f1/Oct4 protein at this stage was synthesized from maternal mRNAs stored in oocytes. The amount of Pou5f1/Oct4 mRNA in the polysomal fraction was small in GV-stage oocytes but was significantly increased in fertilized eggs. Taken together, our results indicate that the synthesis of Pou5f1/Oct4 protein during oogenesis and early stages of embryogenesis is controlled at the level of translation and suggest that precise control of the amount of this protein by translational regulation is important for oocyte development and early embryonic development.
- Klíčová slova
- Embryo, Maternal transcript, Mouse, Oocyte, Translational regulation,
- MeSH
- embryonální vývoj genetika MeSH
- myši inbrední ICR MeSH
- myši MeSH
- oktamerní transkripční faktor 3 genetika metabolismus MeSH
- oogeneze genetika MeSH
- těhotenství MeSH
- vývojová regulace genové exprese genetika MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- oktamerní transkripční faktor 3 MeSH
- Pou5f1 protein, mouse MeSH Prohlížeč
Lamin C2 (LMN C2) is a short product of the lamin a gene. It is a germ cell-specific lamin and has been extensively studied in male germ cells. In this study, we focussed on the expression and localization of LMN C2 in fully-grown germinal vesicle (GV) oocytes. We detected LMN C2 in the fully-grown germinal vesicle oocytes of various mammalian species with confirmation done by immunoblotting the wild type and Lmnc2 gene deleted testes. Expression of LMN C2 tagged with GFP showed localization of LMN C2 to the nuclear membrane of the oocyte. Moreover, the LMN C2 protein notably disappeared after nuclear envelope breakdown (NEBD) and the expression of LMN C2 was significantly reduced in the oocytes from aged females and ceased altogether during meiotic maturation. These results provide new insights regarding LMN C2 expression in the oocytes of various mammalian species.
- MeSH
- jaderný obal genetika MeSH
- laminin genetika MeSH
- meióza genetika MeSH
- messenger RNA genetika MeSH
- myši knockoutované MeSH
- myši MeSH
- oocyty růst a vývoj metabolismus MeSH
- oogeneze genetika MeSH
- ovarium růst a vývoj MeSH
- spermatocyty růst a vývoj MeSH
- testis růst a vývoj MeSH
- vývojová regulace genové exprese genetika MeSH
- zárodečné buňky růst a vývoj MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- lamin C2 MeSH Prohlížeč
- laminin MeSH
- messenger RNA MeSH
Oocyte maturation is essential for proper fertilization, embryo implantation and early development. While the physiological conditions of these processes are relatively well‑known, its exact molecular mechanisms remain widely undiscovered. Oocyte growth, differentiation and maturation are therefore the subject of scientific debate. Precious literature has indicated that the oocyte itself serves a regulatory role in the mechanisms underlying these processes. Hence, the present study performed expression microarrays to analyze the complete transcriptome of porcine oocytes during their in vitro maturation (IVM). Pig material was used for experimentation, as it possesses similarities to the reproductive processes and general genetic proximities of Sus scrofa to human. Oocytes, isolated from the ovaries of slaughtered animals were assessed via the Brilliant Cresyl Blue test and directed to IVM. A number of oocytes were left to be analyzed as the 'before IVM' group. Oocyte mRNA was isolated and used for microarray analysis, which was subsequently validated via RT‑qPCR. The current study particularly focused on genes belonging to 'positive regulation of transcription, DNA‑dependent', 'positive regulation of gene expression', 'positive regulation of macromolecule metabolic process' and 'positive regulation of transcription from RNA polymerase II promoter' ontologies. FOS, VEGFA, ESR1, AR, CCND2, EGR2, ENDRA, GJA1, INHBA, IHH, INSR, APP, WWTR1, SMARCA1, NFAT5, SMAD4, MAP3K1, EGR1, RORA, ECE1, NR5A1, KIT, IKZF2, MEF2C, SH3D19, MITF and PSMB4 were all determined to be significantly altered (fold change, >|2|; P<0.05) among these groups, with their downregulation being observed after IVM. Genes with the most altered expressions were analyzed and considered to be potential markers of maturation associated with transcription regulation and macromolecule metabolism process.
- Klíčová slova
- pig, oocyte, rna, transcription, in vitro maturation,
- MeSH
- biologické markery MeSH
- buněčná diferenciace genetika MeSH
- energetický metabolismus * MeSH
- genetická transkripce MeSH
- genové regulační sítě MeSH
- imunohistochemie MeSH
- kultivované buňky MeSH
- metabolomika MeSH
- oocyty cytologie metabolismus MeSH
- oogeneze genetika MeSH
- ovarium metabolismus MeSH
- prasata MeSH
- stanovení celkové genové exprese MeSH
- transkriptom MeSH
- výpočetní biologie metody MeSH
- vývojová regulace genové exprese * MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- biologické markery MeSH
Although our knowledge regarding oocyte quality and development has improved significantly, the molecular mechanisms that regulate and determine oocyte developmental competence are still unclear. Therefore, the objective of this study was to identify and analyze the transcriptome profiles of porcine oocytes derived from large or small follicles using RNA high-throughput sequencing technology. RNA libraries were constructed from oocytes of large (LO; 3-6 mm) or small (SO; 1.5-1.9 mm) ovarian follicles and then sequenced in an Illumina HiSeq4000. Transcriptome analysis showed a total of 14,557 genes were commonly detected in both oocyte groups. Genes related to the cell cycle, oocyte meiosis, and quality were among the top highly expressed genes in both groups. Differential expression analysis revealed 60 up- and 262 downregulated genes in the LO compared with the SO group. BRCA2, GPLD1, ZP3, ND3, and ND4L were among the highly abundant and highly significant differentially expressed genes (DEGs). The ontological classification of DEGs indicated that protein processing in endoplasmic reticulum was the top enriched pathway. In addition, biological processes related to cell growth and signaling, gene expression regulations, cytoskeleton, and extracellular matrix organization were among the highly enriched processes. In conclusion, this study provides new insights into the global transcriptome changes and the abundance of specific transcripts in porcine oocytes in correlation with follicle size.
- Klíčová slova
- RNAseq, follicular size, oocyte, porcine,
- MeSH
- genové regulační sítě fyziologie MeSH
- oocyty metabolismus MeSH
- oogeneze genetika MeSH
- ovariální folikul cytologie MeSH
- polymerázová řetězová reakce s reverzní transkripcí MeSH
- prasata genetika růst a vývoj MeSH
- signální transdukce genetika MeSH
- stanovení celkové genové exprese MeSH
- transkriptom * MeSH
- vysoce účinné nukleotidové sekvenování MeSH
- vývojová regulace genové exprese fyziologie MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
This paper aims to identify and describe new genetic markers involved in the processes of protein expression and modification reflected in the change of mitochondrial activity before and after in vitro maturation of the oocyte. Porcine oocytes collected from the ovaries of slaughtered landrace gilts were subjected to the process of in vitro maturation. Transcriptomic changes in the expression profile of oocyte genes involved in response to hypoxia, the transmembrane protein receptor serine threonine kinase signaling pathway, the "transforming growth factor β receptor signaling pathway", "response to protein stimulus", and "response to organic substance" were investigated using microarrays. The expression values of these genes in oocytes was analyzed before (immature) and after (mature) in vitro maturation, with significant differences found. All the significantly altered genes showed downregulation after the maturation process. The most changed genes from these gene ontologies, FOS, ID2, VEGFA, BTG2, CYR61, ESR1, AR, TACR3, CCND2, CHRDL1, were chosen to be further validated, described and related to the literature. Additionally, the mitochondrial activity of the analyzed oocytes was measured using specific dyes. We found that the mitochondrial activity was higher before the maturation process. The analysis of these results and the available literature provides a novel insight on the processes that occur during in vitro oocyte maturation. While this knowledge may prove to be useful in further research of the procedures commonly associated with in vitro fertilization procedures, it serves mostly as a basic reference for further proteomic, in vivo, and clinical studies that are necessary to translate it into practical applications.
- Klíčová slova
- microarray, mitochondrial activity, oocyte maturation, pig,
- MeSH
- hypoxie buňky genetika MeSH
- IVM techniky MeSH
- kultivované buňky MeSH
- mitochondrie genetika metabolismus MeSH
- oocyty cytologie metabolismus MeSH
- oogeneze genetika MeSH
- prasata MeSH
- signální transdukce MeSH
- transformující růstový faktor beta metabolismus MeSH
- transkriptom * MeSH
- tyrosinkinasové receptory metabolismus MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- transformující růstový faktor beta MeSH
- tyrosinkinasové receptory MeSH
PROPOSE: The presence of metaphase II (MII) spindle together with the polar body (PB) indicates completion of oocyte maturation. This study was designed to explore if spindle imaging can be used to optimize timing of intracytoplasmic sperm injection (ICSI). METHODS: The study involved 916 oocytes from 234 conventionally stimulated ICSI cycles with an unexpectedly poor ovarian response. All PB-displaying oocytes were subjected to polarized light microscopy (PLM) prior to ICSI. When MII spindle was absent in the majority of oocytes, ICSI was postponed and performed after additional spindle imaging. Fertilization, embryo development, and clinical outcome were evaluated with respect to the observed spindle pattern. RESULTS: The visible spindle was absent in 32.64% of PB-displaying oocytes. The late-maturing oocytes extruding PB in vitro were less likely to exhibit a spindle signal than in vivo matured MII oocytes (38.86% vs. 89.84%). When fertilization was postponed, 59.39% of initially spindle-negative oocytes developed detectable MII spindle. Spindled eggs had significantly higher developmental potential, and the presence of the spindle has been identified as an independent measure for predicting the formation of the blastocyst. Embryos derived from spindle-positive oocytes also showed a higher chance to implant and develop to term. Notably, 11 children were conceived by finely timed fertilization of late-maturing oocytes which are normally discarded. CONCLUSIONS: The study confirms the prognostic value of spindle imaging and demonstrates that immature oocytes can be clinically utilized and give rise to live births when the timing of ICSI is adjusted to their developmental stage.
- Klíčová slova
- Immature oocytes, Meiotic spindle, Oocyte maturation, Polarized light microscopy, Timing of ICSI,
- MeSH
- embryonální vývoj genetika MeSH
- fertilizace in vitro * MeSH
- intracytoplazmatické injekce spermie * MeSH
- lidé MeSH
- metafáze genetika MeSH
- oocyty růst a vývoj ultrastruktura MeSH
- oogeneze genetika MeSH
- polarizační mikroskopie MeSH
- těhotenství MeSH
- Check Tag
- lidé MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
