Ovarian follicles of sterlets (Acipenser ruthenus) are composed of a single oocyte surrounded by follicular cells (FCs), basal lamina, and thecal cells. Previtellogenic oocytes are polarized. Homogeneous ooplasm (contains ribosomes) and granular ooplasm (comprises nuage aggregations of nuclear origin, rough endoplasmic reticulum (RER), Golgi complexes, ribosomes, and mitochondria) are distinguished. Granular ooplasm is initially located near the nucleus, contacts the plasma membrane of the oocyte (oolemma) and forms a thin layer underneath its entire perimeter. Next, a ring that surrounds the nucleus is formed and sends strands directed toward the oolemma. The lipid body composed of lipid droplets forms adjacent to this ring. Later, the granular ooplasm and strands enlarge toward the oolemma, lipid body disperses, and homogeneous ooplasm is no longer present. A thin cortical ooplasm is formed underneath the oolemma and does not contain any organelles. The oocyte nucleus moves to the center. The nucleoplasm contains lampbrush chromosomes, nuclear bodies, and multiple nucleoli. Early vitellogenic oocytes are polarized, too. Three regions in the ooplasm are distinguished: the perinuclear (contains lipid droplets near the nuclear envelope), the endoplasm (contains yolk platelets and lipid droplets), and the periplasm (contains yolk spheres, pigment granules, and microtubules). In all these regions the RER, Golgi complexes, nuage, and mitochondria are present. Micropinocytotic vesicles, Golgi vesicles and precursors of the internal layer of the egg envelope are in the cortical ooplasm. Some FCs delaminate from the follicular epithelium, degenerate and vesicles are released into the perioocytic space. They may contain precursors of egg envelope and may be involved in "cell-cell" communication. The egg envelope (zona radiata, zona pellucida) is made up of three layers: the vitelline envelope (inner layer), the middle layer, and the outer layer. In its deposition, both the oocyte and FCs are engaged.

• MeSH
• cytoplazma MeSH
• oocyty * MeSH
• ovariální folikul * ultrastruktura   MeSH
• ryby MeSH
• vitelogeneze MeSH
• zvířata MeSH
• Check Tag
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem 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.

• 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

Triatomines are vectors of Chagas disease and important model organisms in insect physiology. "Kissing bugs" are obligatory hematophagous insects. A blood meal is required to successfully complete oogenesis, a process primarily controlled by juvenile hormone (JH). We used Dipetalogaster maxima as an experimental model to further understand the roles of JH in the regulation of vitellogenesis and oogenesis. A particular focus was set on the role of JH controlling lipid and protein recruitment by the oocytes. The hemolymph titer of JH III skipped bisepoxide increased after a blood meal. Following a blood meal there were increased levels of mRNAs in the fat body for the yolk protein precursors, vitellogenin (Vg) and lipophorin (Lp), as well as of their protein products in the hemolymph; mRNAs of the Vg and Lp receptors (VgR and LpR) were concomitantly up-regulated in the ovaries. Topical administration of JH induced the expression of Lp/LpR and Vg/VgR genes, and prompted the uptake of Lp and Vg in pre-vitellogenic females. Knockdown of the expression of LpR by RNA interference in fed females did not impair the Lp-mediated lipid transfer to oocytes, suggesting that the bulk of lipid acquisition by oocytes occurred by other pathways rather than by the endocytic Lp/LpR pathway. In conclusion, our results strongly suggest that JH signaling is critical for lipid storage in oocytes, by regulating Vg and Lp gene expression in the fat body as well as by modulating the expression of LpR and VgR genes in ovaries.

• MeSH
• hmyz metabolismus   fyziologie   MeSH
• hmyzí proteiny metabolismus   MeSH
• juvenilní hormony metabolismus   MeSH
• lipoproteiny metabolismus   MeSH
• metabolismus lipidů * MeSH
• oocyty metabolismus   MeSH
• oogeneze fyziologie   MeSH
• ovarium metabolismus   MeSH
• receptory cytoplazmatické a nukleární metabolismus   MeSH
• RNA interference MeSH
• signální transdukce MeSH
• Triatominae * metabolismus   fyziologie   MeSH
• vitelogeneze fyziologie   MeSH
• vitelogeniny metabolismus   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

Regulation of translation is essential for the diverse biological processes involved in development. Particularly, mammalian oocyte development requires the precisely controlled translation of maternal transcripts to coordinate meiotic and early embryo progression while transcription is silent. It has been recently reported that key components of mRNA translation control are short and long noncoding RNAs (ncRNAs). We found that the ncRNABrain cytoplasmic 1 (BC1) has a role in the fully grown germinal vesicle (GV) mouse oocyte, where is highly expressed in the cytoplasm associated with polysomes. Overexpression of BC1 in GV oocyte leads to a minute decrease in global translation with a significant reduction of specific mRNA translation via interaction with the Fragile X Mental Retardation Protein (FMRP). BC1 performs a repressive role in translation only in the GV stage oocyte without forming FMRP or Poly(A) granules. In conclusion, BC1 acts as the translational repressor of specific mRNAs in the GV stage via its binding to a subset of mRNAs and physical interaction with FMRP. The results reported herein contribute to the understanding of the molecular mechanisms of developmental events connected with maternal mRNA translation.

• MeSH
• cytoplazma genetika   metabolismus   MeSH
• myši inbrední ICR MeSH
• myši MeSH
• nekódující RNA genetika   MeSH
• oocyty cytologie   fyziologie   MeSH
• oogeneze * MeSH
• polyribozomy genetika   metabolismus   MeSH
• proteosyntéza * MeSH
• RNA malá cytoplazmatická genetika   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem 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.

• 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

Female fertility relies on successful egg development. Besides chromosome segregation, complex structural and biochemical changes in the cytoplasmic compartment are necessary to confer the female gamete the capacity to undergo normal fertilization and sustain embryonic development. Despite the profound impact on egg quality, morphological bases of cytoplasmic maturation remain largely unknown. Here, we report our findings from the ultrastructural analysis of 69 unfertilized human oocytes from 34 young and healthy egg donors. By comparison of samples fixed at three consecutive developmental stages, we explored how ooplasmic architecture changes during meiotic maturation in vitro. The morphometric image analysis supported observation that the major reorganization of cytoplasm occurs before polar body extrusion. The organelles initially concentrated around prophase nucleus were repositioned toward the periphery and evenly distributed throughout the ooplasm. As maturation progressed, distinct secretory apparatus appeared to transform into cortical granules that clustered underneath the oocyte's surface. The most prominent feature was the gradual formation of heterologous complexes composed of variable elements of endoplasmic reticulum and multiple mitochondria with primitive morphology. Based on the generated image dataset, we proposed a morphological map of cytoplasmic maturation, which may serve as a reference for future comparative studies. In conclusion, this work improves our understanding of human oocyte morphology, cytoplasmic maturation, and intracellular factors defining human egg quality. Although this analysis involved spare oocytes completing development in vitro, it provides essential insight into the enigmatic process by which human egg progenitors prepare for fertilization.

• MeSH
• cytoplazma účinky léků   ultrastruktura   MeSH
• dospělí MeSH
• endoplazmatické retikulum účinky léků   ultrastruktura   MeSH
• folikuly stimulující hormon farmakologie   MeSH
• indukce ovulace MeSH
• lidé MeSH
• mitochondrie účinky léků   ultrastruktura   MeSH
• mladý dospělý MeSH
• oocyty účinky léků   ultrastruktura   MeSH
• oogeneze účinky léků   fyziologie   MeSH
• segregace chromozomů MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mladý dospělý MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem 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.

• 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

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.

• 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

MicroRNAs (miRNAs) are ubiquitous small RNAs guiding post-transcriptional gene repression in countless biological processes. However, the miRNA pathway in mouse oocytes appears inactive and dispensable for development. We propose that marginalization of the miRNA pathway activity stems from the constraints and adaptations of RNA metabolism elicited by the diluting effects of oocyte growth. We report that miRNAs do not accumulate like mRNAs during the oocyte growth because miRNA turnover has not adapted to it. The most abundant miRNAs total tens of thousands of molecules in growing (∅ 40 μm) and fully grown (∅ 80 μm) oocytes, a number similar to that observed in much smaller fibroblasts. The lack of miRNA accumulation results in a 100-fold lower miRNA concentration in fully grown oocytes than in somatic cells. This brings a knock-down-like effect, where diluted miRNAs engage targets but are not abundant enough for significant repression. Low-miRNA concentrations were observed in rat, hamster, porcine and bovine oocytes, arguing that miRNA inactivity is not mouse-specific but a common mammalian oocyte feature. Injection of 250,000 miRNA molecules was sufficient to restore reporter repression in mouse and porcine oocytes, suggesting that miRNA inactivity comes from low-miRNA abundance and not from some suppressor of the pathway.

• MeSH
• buňky 3T3 MeSH
• druhová specificita MeSH
• křečci praví MeSH
• krysa rodu rattus MeSH
• kultivované buňky MeSH
• messenger RNA genetika   metabolismus   MeSH
• mikro RNA genetika   metabolismus   MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• oocyty cytologie   metabolismus   MeSH
• oogeneze * MeSH
• prasata MeSH
• skot MeSH
• teoretické modely MeSH
• vývojová regulace genové exprese MeSH
• zvířata MeSH
• Check Tag
• křečci praví MeSH
• krysa rodu rattus MeSH
• myši MeSH
• skot MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

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