The onset of an early development is, in mammals, characterized by profound changes of multiple aspects of cellular morphology and behavior. These are including, but not limited to, fertilization and the merging of parental genomes with a subsequent transition from the meiotic into the mitotic cycle, followed by global changes of chromatin epigenetic modifications, a gradual decrease in cell size and the initiation of gene expression from the newly formed embryonic genome. Some of these important, and sometimes also dramatic, changes are executed within the period during which the gene transcription is globally silenced or not progressed, and the regulation of most cellular activities, including those mentioned above, relies on controlled translation. It is known that the blastomeres within an early embryo are prone to chromosome segregation errors, which might, when affecting a significant proportion of a cell within the embryo, compromise its further development. In this review, we discuss how the absence of transcription affects the transition from the oocyte to the embryo and what impact global transcriptional silencing might have on the basic cell cycle and chromosome segregation controlling mechanisms.
- Klíčová slova
- cell cycle, embryo, oocyte, transcriptional repression, translation,
- MeSH
- buněčný cyklus genetika MeSH
- chromatin genetika MeSH
- embryo savčí fyziologie MeSH
- embryonální vývoj genetika MeSH
- genetická transkripce genetika MeSH
- lidé MeSH
- segregace chromozomů genetika MeSH
- umlčování genů fyziologie MeSH
- vývojová regulace genové exprese genetika MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Názvy látek
- chromatin MeSH
The Aurora protein kinases are well-established regulators of spindle building and chromosome segregation in mitotic and meiotic cells. In mouse oocytes, there is significant Aurora kinase A (AURKA) compensatory abilities when the other Aurora kinase homologs are deleted. Whether the other homologs, AURKB or AURKC can compensate for loss of AURKA is not known. Using a conditional mouse oocyte knockout model, we demonstrate that this compensation is not reciprocal because female oocyte-specific knockout mice are sterile, and their oocytes fail to complete meiosis I. In determining AURKA-specific functions, we demonstrate that its first meiotic requirement is to activate Polo-like kinase 1 at acentriolar microtubule organizing centers (aMTOCs; meiotic spindle poles). This activation induces fragmentation of the aMTOCs, a step essential for building a bipolar spindle. We also show that AURKA is required for regulating localization of TACC3, another protein required for spindle building. We conclude that AURKA has multiple functions essential to completing MI that are distinct from AURKB and AURKC.
- MeSH
- aparát dělícího vřeténka genetika MeSH
- aurora kinasa A genetika MeSH
- aurora kinasa B genetika MeSH
- aurora kinasa C genetika MeSH
- dělení bunečného jádra genetika MeSH
- fetální proteiny genetika MeSH
- lidé MeSH
- meióza genetika MeSH
- myši MeSH
- oocyty růst a vývoj metabolismus MeSH
- organizační centrum mikrotubulů metabolismus MeSH
- polo-like kinasa 1 MeSH
- póly dělícího vřeténka genetika MeSH
- protein-serin-threoninkinasy genetika MeSH
- proteiny asociované s mikrotubuly genetika MeSH
- proteiny buněčného cyklu genetika MeSH
- protoonkogenní proteiny genetika MeSH
- segregace chromozomů genetika MeSH
- vývojová regulace genové exprese genetika MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
- Názvy látek
- Aurkb protein, mouse MeSH Prohlížeč
- Aurkc protein, mouse MeSH Prohlížeč
- aurora kinasa A MeSH
- aurora kinasa B MeSH
- aurora kinasa C MeSH
- fetální proteiny MeSH
- protein-serin-threoninkinasy MeSH
- proteiny asociované s mikrotubuly MeSH
- proteiny buněčného cyklu MeSH
- protoonkogenní proteiny MeSH
- TACC3 protein, mouse MeSH Prohlížeč
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
Yeast cells must grow to a critical size before committing to division. It is unknown how size is measured. We find that as cells grow, mRNAs for some cell-cycle activators scale faster than size, increasing in concentration, while mRNAs for some inhibitors scale slower than size, decreasing in concentration. Size-scaled gene expression could cause an increasing ratio of activators to inhibitors with size, triggering cell-cycle entry. Consistent with this, expression of the CLN2 activator from the promoter of the WHI5 inhibitor, or vice versa, interfered with cell size homeostasis, yielding a broader distribution of cell sizes. We suggest that size homeostasis comes from differential scaling of gene expression with size. Differential regulation of gene expression as a function of cell size could affect many cellular processes.
- Klíčová slova
- Cln3, cell cycle, cell cycle control, cell cycle regulation, cell size control, growth Whi5, growth control of division, size homeostasis, start, yeast cell cycle,
- MeSH
- buněčné dělení genetika MeSH
- buněčný cyklus genetika MeSH
- cykliny genetika MeSH
- G1 fáze genetika MeSH
- regulace genové exprese u hub genetika MeSH
- Saccharomyces cerevisiae - proteiny genetika MeSH
- Saccharomyces cerevisiae genetika růst a vývoj MeSH
- velikost buňky * MeSH
- vývojová regulace genové exprese genetika MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
- Názvy látek
- CLN2 protein, S cerevisiae MeSH Prohlížeč
- cykliny MeSH
- Saccharomyces cerevisiae - proteiny MeSH
Meiotic maturation of oocyte relies on pre-synthesised maternal mRNA, the translation of which is highly coordinated in space and time. Here, we provide a detailed polysome profiling protocol that demonstrates a combination of the sucrose gradient ultracentrifugation in small SW55Ti tubes with the qRT-PCR-based quantification of 18S and 28S rRNAs in fractionated polysome profile. This newly optimised method, named Scarce Sample Polysome Profiling (SSP-profiling), is suitable for both scarce and conventional sample sizes and is compatible with downstream RNA-seq to identify polysome associated transcripts. Utilising SSP-profiling we have assayed the translatome of mouse oocytes at the onset of nuclear envelope breakdown (NEBD)-a developmental point, the study of which is important for furthering our understanding of the molecular mechanisms leading to oocyte aneuploidy. Our analyses identified 1847 transcripts with moderate to strong polysome occupancy, including abundantly represented mRNAs encoding mitochondrial and ribosomal proteins, proteasomal components, glycolytic and amino acids synthetic enzymes, proteins involved in cytoskeleton organization plus RNA-binding and translation initiation factors. In addition to transcripts encoding known players of meiotic progression, we also identified several mRNAs encoding proteins of unknown function. Polysome profiles generated using SSP-profiling were more than comparable to those developed using existing conventional approaches, being demonstrably superior in their resolution, reproducibility, versatility, speed of derivation and downstream protocol applicability.
- Klíčová slova
- RNA-seq, SW55Ti rotor, mouse early embryo, mouse oocyte, mouse zygote, polysome fractionation, polysome profiling, translatome,
- MeSH
- jaderný obal genetika metabolismus MeSH
- meióza genetika MeSH
- myši MeSH
- oocyty růst a vývoj metabolismus MeSH
- polyribozomy genetika MeSH
- proteiny vázající RNA genetika MeSH
- RNA messenger skladovaná genetika MeSH
- RNA ribozomální 18S genetika MeSH
- RNA ribozomální 28S genetika MeSH
- sekvenování transkriptomu MeSH
- vývojová regulace genové exprese genetika MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- proteiny vázající RNA MeSH
- RNA messenger skladovaná MeSH
- RNA ribozomální 18S MeSH
- RNA ribozomální 28S MeSH
The Wnt, TGF-β, and Notch signaling pathways are essential for the regulation of cellular polarity, differentiation, proliferation, and migration. Differential activation and mutual crosstalk of these pathways during animal development are crucial instructive forces in the initiation of the body axis and the development of organs and tissues. Due to the ability to initiate cell proliferation, these pathways are vulnerable to somatic mutations selectively producing cells, which ultimately slip through cellular and organismal checkpoints and develop into cancer. The architecture of the Wnt, TGF-β, and Notch signaling pathways is simple. The transmembrane receptor, activated by the extracellular stimulus, induces nuclear translocation of the transcription factor, which subsequently changes the expression of target genes. Nevertheless, these pathways are regulated by a myriad of factors involved in various feedback mechanisms or crosstalk. The most prominent group of regulators is the ubiquitin-proteasome system (UPS). To open the door to UPS-based therapeutic manipulations, a thorough understanding of these regulations at a molecular level and rigorous confirmation in vivo are required. In this quest, mouse models are exceptional and, thanks to the progress in genetic engineering, also an accessible tool. Here, we reviewed the current understanding of how the UPS regulates the Wnt, TGF-β, and Notch pathways and we summarized the knowledge gained from related mouse models.
- Klíčová slova
- cancer, gene inactivation, mouse model, ubiquitin–proteasome system,
- MeSH
- beta-katenin metabolismus MeSH
- buněčná diferenciace fyziologie MeSH
- homeostáza genetika MeSH
- ligasy metabolismus MeSH
- myši embryologie genetika MeSH
- proliferace buněk fyziologie MeSH
- proteiny Wnt metabolismus MeSH
- receptory Notch metabolismus MeSH
- signální dráha Wnt fyziologie MeSH
- transformující růstový faktor beta metabolismus MeSH
- transkripční faktory metabolismus MeSH
- ubikvitin metabolismus MeSH
- ubikvitinligasy metabolismus fyziologie MeSH
- vývojová regulace genové exprese genetika MeSH
- zvířata MeSH
- Check Tag
- myši embryologie genetika MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
- Názvy látek
- beta-katenin MeSH
- ligasy MeSH
- proteiny Wnt MeSH
- receptory Notch MeSH
- transformující růstový faktor beta MeSH
- transkripční faktory MeSH
- ubikvitin MeSH
- ubikvitinligasy MeSH
The physiological processes that drive the development of ovarian follicle, as well as the process of oogenesis, are quite well known. Granulosa cells are major players in this occurrence, being the somatic element of the female gamete development. They participate directly in the processes of oogenesis, building the cumulus-oocyte complex surrounding the ovum. In addition to that, they have a further impact on the reproductive processes, being a place of steroid sex hormone synthesis and secretion. It is known that the follicle development creates a major need for angiogenesis and blood vessel development in the ovary. In this study, we use novel molecular approaches to analyze markers of these processes in porcine granulosa cultured primarily in vitro. The cells were recovered from mature sus scrofa specimen after slaughter. They were then subjected to enzymatic digestion and culture primarily for a short term. The RNA was extracted from cultures in specific time periods (0h, 24h, 48h, 96h, and 144h) and analyzed using expression microarrays. The genes that exhibited fold change bigger than |2|, and adjusted p-value lower than 0.05, were considered differentially expressed. From these, we have chosen the members of "angiogenesis," "blood vessel development," "blood vessel morphogenesis," "cardiovascular system development," and "vasculature development" for further selection. CCL2, FGFR2, SFRP2, PDPN, DCN, CAV1, CHI3L1, ITGB3, FN1, and LOX which are upregulated, as well as CXCL10, NEBL, IHH, TGFBR3, SCUBE1, IGF1, EDNRA, RHOB, PPARD, and SLITRK5 genes whose expression is downregulated through the time of culture, were chosen as the potential markers, as their expression varied the most during the time of culture. The fold changes were further validated with RT-qPCR. The genes were described, with special attention to their possible function in GCs during culture. The results broaden the general knowledge about GC's in vitro molecular processes and might serve as a point of reference for further in vivo and clinical studies.
- MeSH
- cévy růst a vývoj metabolismus MeSH
- folikulární buňky cytologie metabolismus MeSH
- fyziologická neovaskularizace genetika MeSH
- lidé MeSH
- morfogeneze genetika MeSH
- oocyty růst a vývoj MeSH
- oogeneze genetika MeSH
- ovariální folikul růst a vývoj MeSH
- ovarium růst a vývoj metabolismus MeSH
- prasata MeSH
- primární buněčná kultura MeSH
- proteosyntéza genetika MeSH
- vývojová regulace genové exprese genetika MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Zygotic genome activation (ZGA) denotes the initiation of gene expression after fertilization. It is part of the complex oocyte-to-embryo transition (OET) in which a highly specialized cell - the oocyte - is fertilized and transformed into a zygote that gives rise to an embryo that will develop into a newborn. From the perspective of gene expression, the OET reflects reprogramming of germ cell gene expression into the new developmental program of the zygote. This reprogramming occurs at transcriptional and post-transcriptional levels. This review will discuss selected aspects of mammalian ZGA, highlighting shared features and evolved differences observed in commonly investigated mammals and non-mammalian model animals.
- Klíčová slova
- Chromatin, DNA methylation, Epigenetics, Gene expression, Histone modifications, Oocyte-to-embryo transition, Protamine/histone exchange, Retrotransponsons, Transcription, Zygotic genome activation,
- MeSH
- embryo savčí cytologie MeSH
- fertilizace genetika MeSH
- lidé MeSH
- oocyty cytologie MeSH
- savci MeSH
- vývojová regulace genové exprese genetika MeSH
- zvířata MeSH
- zygota cytologie MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
The formation of the vertebrate brain requires the generation, migration, differentiation and survival of neurons. Genetic mutations that perturb these critical cellular events can result in malformations of the telencephalon, providing a molecular window into brain development. Here we report the identification of an N-ethyl-N-nitrosourea-induced mouse mutant characterized by a fractured hippocampal pyramidal cell layer, attributable to defects in neuronal migration. We show that this is caused by a hypomorphic mutation in Vps15 that perturbs endosomal-lysosomal trafficking and autophagy, resulting in an upregulation of Nischarin, which inhibits Pak1 signaling. The complete ablation of Vps15 results in the accumulation of autophagic substrates, the induction of apoptosis and severe cortical atrophy. Finally, we report that mutations in VPS15 are associated with cortical atrophy and epilepsy in humans. These data highlight the importance of the Vps15-Vps34 complex and the Nischarin-Pak1 signaling hub in the development of the telencephalon.
- MeSH
- alkylační látky toxicita MeSH
- atrofie chemicky indukované genetika patologie MeSH
- autofagie účinky léků genetika MeSH
- embryo savčí MeSH
- ethylnitrosomočovina toxicita MeSH
- lidé MeSH
- modely nemocí na zvířatech MeSH
- mozek účinky léků patologie MeSH
- mutace účinky léků MeSH
- myši inbrední C57BL MeSH
- myši transgenní MeSH
- myši MeSH
- neurony účinky léků patologie ultrastruktura MeSH
- neurovývojové poruchy * chemicky indukované diagnostické zobrazování genetika patologie MeSH
- novorozená zvířata MeSH
- pohyb buněk účinky léků genetika MeSH
- signální transdukce účinky léků genetika MeSH
- vakuolární protonové ATPasy účinky léků genetika MeSH
- vývojová regulace genové exprese účinky léků genetika MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- alkylační látky MeSH
- ethylnitrosomočovina MeSH
- vakuolární protonové ATPasy MeSH
- Vps50 protein, mouse MeSH Prohlížeč