Nejvíce citovaný článek - PubMed ID 15501230
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
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
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.
- Klíčová slova
- Non-coding RNA, development, embryo, oocyte, 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
- Názvy látek
- nekódující RNA MeSH
- RNA malá cytoplazmatická 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
Granulosa cells (GCs) are somatic cells essential for establishing and maintaining bi-directional communication with the oocytes. This connection has a profound importance for the delivery of energy substrates, structural components and ions to the maturing oocyte through gap junctions. Cumulus cells, group of closely associated GCs, surround the oocyte and can diminished the effect of harmful environmental insults. Both GCs and oocytes prefer different energy substrates in their cellular metabolism: GCs are more glycolytic, whereas oocytes rely more on oxidative phosphorylation pathway. The interconnection of these cells is emphasized by the fact that GCs supply oocytes with intermediates produced in glycolysis. The number of GCs surrounding the oocyte and their age affect the energy status of oocytes. This review summarises available studies collaboration of cellular types in the ovarian follicle from the point of view of energy metabolism, signaling and protection of toxic insults. A deeper knowledge of the underlying mechanisms is crucial for better methods to prevent and treat infertility and to improve the technology of in vitro fertilization.
- MeSH
- antioxidancia metabolismus MeSH
- energetický metabolismus MeSH
- folikulární buňky účinky léků metabolismus MeSH
- lidé MeSH
- metabolismus lipidů MeSH
- metabolismus sacharidů MeSH
- nebezpečné látky toxicita MeSH
- oocyty růst a vývoj metabolismus MeSH
- reaktivní formy kyslíku metabolismus MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Názvy látek
- antioxidancia MeSH
- nebezpečné látky MeSH
- reaktivní formy kyslíku 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
In the absence of transcription, the regulation of gene expression in oocytes is controlled almost exclusively at the level of transcriptome and proteome stabilization, and translation. A subset of maternal transcripts is stored in a translationally dormant state in the oocyte, and temporally driven translation of specific mRNAs propel meiotic progression, oocyte-to-embryo transition and early embryo development. We identified Ank2.3 as the only transcript variant present in the mouse oocyte and discovered that it is translated after nuclear envelope breakdown. Here we show that Ank2.3 mRNA is localized in higher concentration in the oocyte nucleoplasm and, after nuclear envelope breakdown, in the newly forming spindle where its translation occurs. Furthermore, we reveal that Ank2.3 mRNA contains an oligo-pyrimidine motif at 5'UTR that predetermines its translation through a cap-dependent pathway. Lastly, we show that prevention of ANK2 translation leads to abnormalities in oocyte cytokinesis.
- MeSH
- ankyriny genetika metabolismus MeSH
- časoprostorová analýza * MeSH
- cytokineze * MeSH
- embryo savčí cytologie fyziologie MeSH
- meióza * MeSH
- messenger RNA genetika metabolismus MeSH
- myši MeSH
- oocyty cytologie fyziologie MeSH
- oogeneze MeSH
- vývojová regulace genové exprese * MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- Ank2 protein, mouse MeSH Prohlížeč
- ankyriny MeSH
- messenger RNA MeSH
The oocyte-to-embryo transition (OET) arguably initiates with formation of a primordial follicle and culminates with reprogramming of gene expression during the course of zygotic genome activation. This transition results in converting a highly differentiated cell, i.e. oocyte, to undifferentiated cells, i.e. initial blastomeres of a preimplantation embryo. A plethora of changes occur during the OET and include, but are not limited to, changes in transcription, chromatin structure, and protein synthesis; accumulation of macromolecules and organelles that will comprise the oocyte's maternal contribution to the early embryo; sequential acquisition of meiotic and developmental competence to name but a few. This review will focus on transcriptional and post-transcriptional changes that occur during OET in mouse because such changes are likely the major driving force for OET. We often take a historical and personal perspective, and highlight how advances in experimental methods often catalyzed conceptual advances in understanding the molecular bases for OET. We also point out questions that remain open and therefore represent topics of interest for future investigation.
- MeSH
- buněčná diferenciace fyziologie MeSH
- embryonální vývoj fyziologie MeSH
- genom MeSH
- myši MeSH
- oocyty fyziologie MeSH
- ovariální folikul fyziologie MeSH
- vývojová regulace genové exprese MeSH
- zvířata 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, N.I.H., Intramural MeSH
The fully grown mammalian oocyte is transcriptionally quiescent and utilizes only transcripts synthesized and stored during early development. However, we find that an abundant RNA population is retained in the oocyte nucleus and contains specific mRNAs important for meiotic progression. Here we show that during the first meiotic division, shortly after nuclear envelope breakdown, translational hotspots develop in the chromosomal area and in a region that was previously surrounded the nucleus. These distinct translational hotspots are separated by endoplasmic reticulum and Lamin, and disappear following polar body extrusion. Chromosomal translational hotspots are controlled by the activity of the mTOR-eIF4F pathway. Here we reveal a mechanism that-following the resumption of meiosis-controls the temporal and spatial translation of a specific set of transcripts required for normal spindle assembly, chromosome alignment and segregation.
- MeSH
- časové faktory MeSH
- down regulace MeSH
- eukaryotický iniciační faktor 4F metabolismus MeSH
- fertilizace MeSH
- jaderný obal metabolismus MeSH
- lidé MeSH
- meióza MeSH
- messenger RNA genetika metabolismus MeSH
- myši MeSH
- nestabilita genomu MeSH
- oocyty metabolismus MeSH
- proteosyntéza * MeSH
- RNA čepičky metabolismus MeSH
- savčí chromozomy metabolismus MeSH
- savci metabolismus MeSH
- signální transdukce * MeSH
- TOR serin-threoninkinasy metabolismus MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- eukaryotický iniciační faktor 4F MeSH
- messenger RNA MeSH
- RNA čepičky MeSH
- TOR serin-threoninkinasy MeSH