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

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

Fully grown mammalian oocytes store a large amount of RNA synthesized during the transcriptionally active growth stage. A large part of the stored RNA belongs to the long non-coding class which contain either transcriptional noise or important contributors to cellular physiology. Despite the expanding number of studies related to lncRNAs, their influence on oocyte physiology remains enigmatic. We found an oocyte specific antisense, long non-coding RNA, "Rose" (lncRNA in Oocyte Specifically Expressed) expressed in two variants containing two and three non-coding exons, respectively. Rose is localized in the nucleus of transcriptionally active oocyte and in embryo with polysomal occupancy in the cytoplasm. Experimental overexpression of Rose in fully grown oocyte did not show any differences in meiotic maturation. However, knocking down Rose resulted in abnormalities in oocyte cytokinesis and impaired preimplantation embryo development. In conclusion, we have identified an oocyte-specific maternal lncRNA that is essential for successful mammalian oocyte and embryo development.

• Klíčová slova
• Early embryo, LncRNA, Meiosis, Oocyte, Polysome,
• Publikační typ
• časopisecké články 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

The degradation of maternally provided molecules is a very important process during early embryogenesis. However, the vast majority of studies deals with mRNA degradation and protein degradation is only a very little explored process yet. The aim of this article was to summarize current knowledge about the protein degradation during embryogenesis of mammals. In addition to resuming of known data concerning mammalian embryogenesis, we tried to fill the gaps in knowledge by comparison with facts known about protein degradation in early embryos of non-mammalian species. Maternal protein degradation seems to be driven by very strict rules in terms of specificity and timing. The degradation of some maternal proteins is certainly necessary for the normal course of embryonic genome activation (EGA) and several concrete proteins that need to be degraded before major EGA have been already found. Nevertheless, the most important period seems to take place even before preimplantation development-during oocyte maturation. The defects arisen during this period seems to be later irreparable.

• Klíčová slova
• Autophagy, Embryonic genome activation, Maternal to zygotic transition, Proteasome system, Ubiquitin, Ubiquitin ligase,
• MeSH
• embryo nesavčí metabolismus   fyziologie   MeSH
• embryo savčí metabolismus   fyziologie   MeSH
• embryonální vývoj fyziologie   MeSH
• genom fyziologie   MeSH
• lidé MeSH
• oocyty metabolismus   fyziologie   MeSH
• proteiny metabolismus   MeSH
• vývojová regulace genové exprese fyziologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• proteiny 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
• Názvy látek
• lamin C2 MeSH Prohlížeč
• laminin MeSH
• messenger RNA 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

Oocyte meiotic maturation and embryogenesis are some of the most important physiological processes that occur in organisms, playing crucial roles in the preservation of life in all species. The post-transcriptional regulation of maternal messenger ribonucleic acids (mRNAs) and the post-translational regulation of proteins are critical in the control of oocyte maturation and early embryogenesis. Translational control affects the basic mechanism of protein synthesis, thus, knowledge of the key components included in this machinery is required in order to understand its regulation. Cytoplasmic polyadenylation element binding proteins (CPEBs) bind to the 3'-end of mRNAs to regulate their localization and translation and are necessary for proper development. In this study we examined the expression pattern of cytoplasmic polyadenylation element binding protein 2 (CPEB2) both on the mRNA (by real-time quantitative reverse transcription polymerase chain reaction, qRT-PCR) and protein (by Western blotting, WB) level, as well as its localization during the meiotic maturation of porcine oocytes and early embryonic development by immunocytochemistry (ICC). For the elucidation of its functions, CPEB2 knockdown by double-strand RNA (dsRNA) was used. We discovered that CPEB2 is expressed during all stages of porcine meiotic maturation and embryonic development. Moreover, we found that it is necessary to enable a high percentage of oocytes to reach the metaphase II (MII) stage, as well as for the production of good-quality parthenogenetic blastocysts.

• Klíčová slova
• CPEB2, CPEBs, embryonic development, oocyte maturation, translational control,
• MeSH
• 3' nepřekládaná oblast MeSH
• embryonální vývoj MeSH
• genový knockdown MeSH
• meióza * MeSH
• messenger RNA metabolismus   MeSH
• oocyty cytologie   metabolismus   MeSH
• partenogeneze MeSH
• prasata MeSH
• proteiny vázající RNA genetika   metabolismus   MeSH
• těhotenství MeSH
• vývojová regulace genové exprese MeSH
• zvířata MeSH
• Check Tag
• těhotenství MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• 3' nepřekládaná oblast MeSH
• messenger RNA MeSH
• proteiny vázající RNA MeSH