Transcriptional activity and gene expression are critical for the development of mature, meiotically competent oocytes. Our study demonstrates that the absence of cyclin-dependent kinase 12 (CDK12) in oocytes leads to complete female sterility, as fully developed oocytes capable of completing meiosis I are absent from the ovaries. Mechanistically, CDK12 regulates RNA polymerase II activity in growing oocytes and ensures the maintenance of the physiological maternal transcriptome, which is essential for protein synthesis that drives further oocyte growth. Notably, CDK12-deficient growing oocytes exhibit a 71% reduction in transcriptional activity. Furthermore, impaired oocyte development disrupts folliculogenesis, leading to premature ovarian failure without terminal follicle maturation or ovulation. In conclusion, our findings identify CDK12 as a key master regulator of the oocyte transcriptional program and gene expression, indispensable for oocyte growth and female fertility. A schematic illustrating the effects of loss of CDK12 in mammalian oocytes on the regulation of transcription by polymerase II and the concomitant effects on translation. This disruption leads to an aberrant transcriptome and translatome, resulting in the absence of fully mature oocytes and ultimately female sterility.
- MeSH
- cyklin-dependentní kinasy * metabolismus genetika MeSH
- meióza genetika MeSH
- myši MeSH
- oocyty * metabolismus MeSH
- RNA-polymerasa II metabolismus MeSH
- transkriptom genetika MeSH
- ženská infertilita * genetika patologie metabolismus MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- CDK12 protein, human MeSH Prohlížeč
- cyklin-dependentní kinasy * MeSH
- RNA-polymerasa II MeSH
Mammalian oocyte development depends on the temporally controlled translation of maternal transcripts, particularly in the coordination of meiotic and early embryonic development when transcription has ceased. The translation of mRNA is regulated by various RNA-binding proteins. We show that the absence of cytoplasmic polyadenylation element-binding protein 3 (CPEB3) negatively affects female reproductive fitness. CPEB3-depleted oocytes undergo meiosis normally but experience early embryonic arrest due to a disrupted transcriptome, leading to aberrant protein expression and the subsequent failure of embryonic transcription initiation. We found that CPEB3 stabilizes a subset of mRNAs with a significantly longer 3'UTR that is enriched in its distal region with cytoplasmic polyadenylation elements. Overall, our results suggest that CPEB3 is an important maternal factor that regulates the stability and translation of a subclass of mRNAs that are essential for the initiation of embryonic transcription and thus for embryonic development.
- Klíčová slova
- embryo, mRNA, oocyte, translation,
- MeSH
- 3' nepřekládaná oblast genetika MeSH
- embryonální vývoj genetika MeSH
- meióza genetika MeSH
- messenger RNA genetika metabolismus MeSH
- myši MeSH
- oocyty * metabolismus MeSH
- polyadenylace MeSH
- proteiny vázající RNA * metabolismus genetika MeSH
- stabilita RNA genetika MeSH
- vývojová regulace genové exprese MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- 3' nepřekládaná oblast MeSH
- Cpeb3 protein, mouse MeSH Prohlížeč
- messenger RNA MeSH
- proteiny vázající RNA * MeSH
Translation is critical for development as transcription in the oocyte and early embryo is silenced. To illustrate the translational changes during meiosis and consecutive two mitoses of the oocyte and early embryo, we performed a genome-wide translatome analysis. Acquired data showed significant and uniform activation of key translational initiation and elongation axes specific to M-phases. Although global protein synthesis decreases in M-phases, translation initiation and elongation activity increases in a uniformly fluctuating manner, leading to qualitative changes in translation regulation via the mTOR1/4F/eEF2 axis. Overall, we have uncovered a highly dynamic and oscillatory pattern of translational reprogramming that contributes to the translational regulation of specific mRNAs with different modes of polysomal occupancy/translation that are important for oocyte and embryo developmental competence. Our results provide new insights into the regulation of gene expression during oocyte meiosis as well as the first two embryonic mitoses and show how temporal translation can be optimized. This study is the first step towards a comprehensive analysis of the molecular mechanisms that not only control translation during early development, but also regulate translation-related networks employed in the oocyte-to-embryo transition and embryonic genome activation.
- MeSH
- embryonální vývoj * MeSH
- meióza MeSH
- messenger RNA genetika metabolismus MeSH
- myši MeSH
- oocyty * cytologie růst a vývoj metabolismus MeSH
- proteosyntéza * MeSH
- vývojová regulace genové exprese MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- messenger RNA MeSH
During oocyte growth the cell accumulates RNAs to contribute to oocyte and embryo development which progresses with ceased transcription. To investigate the subcellular distribution of specific RNAs and their translation we developed a technique revealing several instances of localized translation with distinctive regulatory implications. We analyzed the localization and expression of candidate non-coding and mRNAs in the mouse oocyte and embryo. Furthermore, we established simultaneous visualization of mRNA and in situ translation events validated with polysomal occupancy. We discovered that translationally dormant and abundant mRNAs CyclinB1 and Mos are localized in the cytoplasm of the fully grown GV oocyte forming cloud-like structures with consequent abundant translation at the center of the MII oocyte. Coupling detection of the localization of specific single mRNA molecules with their translation at the subcellular context is a valuable tool to quantitatively study temporal and spatial translation of specific target mRNAs to understand molecular processes in the developing cell.
- Klíčová slova
- imaging, localization, mRNA, subcellular, translation,
- MeSH
- cyklin B1 genetika MeSH
- cytoplazma genetika MeSH
- embryo savčí chemie MeSH
- hybridizace in situ fluorescenční MeSH
- messenger RNA genetika MeSH
- myši MeSH
- nekódující RNA genetika MeSH
- oocyty chemie růst a vývoj MeSH
- polyribozomy genetika MeSH
- proteosyntéza MeSH
- protoonkogenní proteiny c-mos genetika MeSH
- vývojová regulace genové exprese MeSH
- zobrazení jednotlivé molekuly metody MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- Ccnb1 protein, mouse MeSH Prohlížeč
- cyklin B1 MeSH
- messenger RNA MeSH
- nekódující RNA MeSH
- protoonkogenní proteiny c-mos MeSH
Successful specification of the two mouse blastocyst inner cell mass (ICM) lineages (the primitive endoderm (PrE) and epiblast) is a prerequisite for continued development and requires active fibroblast growth factor 4 (FGF4) signaling. Previously, we identified a role for p38 mitogen-activated protein kinases (p38-MAPKs) during PrE differentiation, but the underlying mechanisms have remained unresolved. Here, we report an early blastocyst window of p38-MAPK activity that is required to regulate ribosome-related gene expression, rRNA precursor processing, polysome formation and protein translation. We show that p38-MAPK inhibition-induced PrE phenotypes can be partially rescued by activating the translational regulator mTOR. However, similar PrE phenotypes associated with extracellular signal-regulated kinase (ERK) pathway inhibition targeting active FGF4 signaling are not affected by mTOR activation. These data indicate a specific role for p38-MAPKs in providing a permissive translational environment during mouse blastocyst PrE differentiation that is distinct from classically reported FGF4-based mechanisms.
- MeSH
- blastocysta fyziologie MeSH
- buněčná diferenciace MeSH
- buněčný rodokmen MeSH
- DNA vazebné proteiny fyziologie MeSH
- embryonální vývoj MeSH
- endoderm cytologie MeSH
- mitogenem aktivované proteinkinasy p38 antagonisté a inhibitory fyziologie MeSH
- myši MeSH
- proteiny vázající RNA fyziologie MeSH
- proteosyntéza * MeSH
- TOR serin-threoninkinasy fyziologie MeSH
- transkripční faktory fyziologie MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- DNA vazebné proteiny MeSH
- mitogenem aktivované proteinkinasy p38 MeSH
- mTOR protein, mouse MeSH Prohlížeč
- Mybbp1a protein, mouse MeSH Prohlížeč
- proteiny vázající RNA MeSH
- TOR serin-threoninkinasy MeSH
- transkripční faktory MeSH
Increasing maternal age in mammals is associated with poorer oocyte quality, involving higher aneuploidy rates and decreased developmental competence. Prior to resumption of meiosis, fully developed mammalian oocytes become transcriptionally silent until the onset of zygotic genome activation. Therefore, meiotic progression and early embryogenesis are driven largely by translational utilization of previously synthesized mRNAs. We report that genome-wide translatome profiling reveals considerable numbers of transcripts that are differentially translated in oocytes obtained from aged compared to young females. Additionally, we show that a number of aberrantly translated mRNAs in oocytes from aged females are associated with cell cycle. Indeed, we demonstrate that four specific maternal age-related transcripts (Sgk1, Castor1, Aire and Eg5) with differential translation rates encode factors that are associated with the newly forming meiotic spindle. Moreover, we report substantial defects in chromosome alignment and cytokinesis in the oocytes of young females, in which candidate CASTOR1 and SGK1 protein levels or activity are experimentally altered. Our findings indicate that improper translation of specific proteins at the onset of meiosis contributes to increased chromosome segregation problems associated with female ageing.
- MeSH
- lidé MeSH
- oocyty metabolismus MeSH
- savci MeSH
- věkové faktory MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Cyclin dependent kinase 1 (CDK1) has been primarily identified as a key cell cycle regulator in both mitosis and meiosis. Recently, an extramitotic function of CDK1 emerged when evidence was found that CDK1 is involved in many cellular events that are essential for cell proliferation and survival. In this review we summarize the involvement of CDK1 in the initiation and elongation steps of protein synthesis in the cell. During its activation, CDK1 influences the initiation of protein synthesis, promotes the activity of specific translational initiation factors and affects the functioning of a subset of elongation factors. Our review provides insights into gene expression regulation during the transcriptionally silent M-phase and describes quantitative and qualitative translational changes based on the extramitotic role of the cell cycle master regulator CDK1 to optimize temporal synthesis of proteins to sustain the division-related processes: mitosis and cytokinesis.
- Klíčová slova
- 4E-BP1, CDK1, M-phase, mRNA, mTOR, translation,
- MeSH
- buněčný cyklus genetika fyziologie MeSH
- lidé MeSH
- messenger RNA genetika metabolismus MeSH
- proteinkinasa CDC2 genetika metabolismus MeSH
- proteiny buněčného cyklu genetika metabolismus MeSH
- TOR serin-threoninkinasy genetika metabolismus MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
- Názvy látek
- messenger RNA MeSH
- proteinkinasa CDC2 MeSH
- proteiny buněčného cyklu MeSH
- TOR serin-threoninkinasy MeSH
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
- Publikační typ
- tisková chyba MeSH
In several species, including Xenopus, mouse and human, two members of cyclin A family were identified. Cyclin A2, which is ubiquitously expressed in dividing cells and plays role in DNA replication, entry into mitosis and spindle assembly, and cyclin A1, whose function is less clear and which is expressed in spermatocytes, leukemia cells and in postmitotic multiciliated cells. Deletion of the gene showed that cyclin A1 is essential for male meiosis, but nonessential for female meiosis. Our results revealed, that the cyclin A1 is not only dispensable in oocytes, we show here that its expression is in fact undesirable in these cells. Our data demonstrate that the APC/C and proteasome in oocytes are unable to target sufficiently cyclin A1 before anaphase, which leads into anaphase arrest and direct inhibition of separase. The cyclin A1-induced cell cycle arrest is oocyte-specific and the presence of cyclin A1 in early embryos has no effect on cell cycle progression or chromosome division. Cyclin A1 is therefore not only an important cell cycle regulator with biased expression in germline, being essential for male and damaging for female meiosis, its persistent expression during anaphase in oocytes shows fundamental differences between APC/C function in oocytes and in early embryos.
- MeSH
- anafáze * MeSH
- cyklin A1 fyziologie MeSH
- cyklin A2 fyziologie MeSH
- fluorescenční mikroskopie MeSH
- meióza MeSH
- metafáze MeSH
- mikroinjekce MeSH
- myši MeSH
- oocyty cytologie MeSH
- proteasomový endopeptidasový komplex fyziologie MeSH
- segregace chromozomů * 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
- Ccna1 protein, mouse MeSH Prohlížeč
- CCNA2 protein, mouse MeSH Prohlížeč
- cyklin A1 MeSH
- cyklin A2 MeSH
- proteasomový endopeptidasový komplex MeSH
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
- Publikační typ
- tisková chyba MeSH
