Nejvíce citovaný článek - PubMed ID 19633130
AKT (protein kinase B) is implicated in meiotic maturation of porcine oocytes
Gibel carp (Carassius gibelio) is a cyprinid fish that originated in eastern Eurasia and is considered as invasive in European freshwater ecosystems. The populations of gibel carp in Europe are mostly composed of asexually reproducing triploid females (i.e., reproducing by gynogenesis) and sexually reproducing diploid females and males. Although some cases of coexisting sexual and asexual reproductive forms are known in vertebrates, the molecular mechanisms maintaining such coexistence are still in question. Both reproduction modes are supposed to exhibit evolutionary and ecological advantages and disadvantages. To better understand the coexistence of these two reproduction strategies, we performed transcriptome profile analysis of gonad tissues (ovaries) and studied the differentially expressed reproduction-associated genes in sexual and asexual females. We used high-throughput RNA sequencing to generate transcriptomic profiles of gonadal tissues of triploid asexual females and males, diploid sexual males and females of gibel carp, as well as diploid individuals from two closely-related species, C. auratus and Cyprinus carpio. Using SNP clustering, we showed the close similarity of C. gibelio and C. auratus with a basal position of C. carpio to both Carassius species. Using transcriptome profile analyses, we showed that many genes and pathways are involved in both gynogenetic and sexual reproduction in C. gibelio; however, we also found that 1500 genes, including 100 genes involved in cell cycle control, meiosis, oogenesis, embryogenesis, fertilization, steroid hormone signaling, and biosynthesis were differently expressed in the ovaries of asexual and sexual females. We suggest that the overall downregulation of reproduction-associated pathways in asexual females, and their maintenance in sexual ones, allows the populations of C. gibelio to combine the evolutionary and ecological advantages of the two reproductive strategies. However, we showed that many sexual-reproduction-related genes are maintained and expressed in asexual females, suggesting that gynogenetic gibel carp retains the genetic toolkits for meiosis and sexual reproduction. These findings shed new light on the evolution of this asexual and sexual complex.
- Klíčová slova
- Asexual reproduction, Carassius gibelio, Differential expression analysis, Evolution of sexual reproduction, Gynogenesis, Meiosis, Oogenesis, Reproduction, Transcriptomics,
- MeSH
- jednonukleotidový polymorfismus MeSH
- kapři * genetika fyziologie MeSH
- nepohlavní rozmnožování * genetika MeSH
- ovarium metabolismus MeSH
- rozmnožování * genetika MeSH
- stanovení celkové genové exprese MeSH
- transkriptom MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
A serine/threonine-specific protein kinase B (PKB), also known as Akt, is a key factor in the phosphoinositide 3-kinase (PI3K)/Akt signaling pathway that regulates cell survival, metabolism and proliferation. Akt phosphorylates many downstream specific substrates, which subsequently control the nuclear envelope breakdown (NEBD), centrosome maturation, spindle assembly, chromosome segregation, and cytokinesis. In vertebrates, Akt is also an important player during oogenesis and preimplantation development. In the signaling pathways regulating mRNA translation, Akt is involved in the control of mammalian target of rapamycin complex 1 (mTORC1) and thereby regulates the activity of a translational repressor, the eukaryotic initiation factor 4E (eIF4E) binding protein 1 (4E-BP1). In this review, we summarize the functions of Akt in mitosis, meiosis and early embryonic development. Additionally, the role of Akt in the regulation of mRNA translation is addressed with respect to the significance of this process during early development.
- Klíčová slova
- Akt kinase, early embryo, mRNA translation, mTORC1, meiosis, mitosis, oocyte, spindle,
- MeSH
- 1-fosfatidylinositol-3-kinasa metabolismus MeSH
- embryonální vývoj MeSH
- fosfatidylinositol-3-kinasy * metabolismus MeSH
- fosfoproteiny metabolismus MeSH
- fosforylace genetika MeSH
- oocyty metabolismus MeSH
- oogeneze MeSH
- protein-serin-threoninkinasy metabolismus MeSH
- protoonkogenní proteiny c-akt * metabolismus MeSH
- savci metabolismus MeSH
- signální transdukce MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
- Názvy látek
- 1-fosfatidylinositol-3-kinasa MeSH
- fosfatidylinositol-3-kinasy * MeSH
- fosfoproteiny MeSH
- protein-serin-threoninkinasy MeSH
- protoonkogenní proteiny c-akt * MeSH
Cells are equipped with a diverse network of signaling and regulatory proteins that function as cell cycle regulators and checkpoint proteins to ensure the proper progression of cell division. A key regulator of cell division is polo-like kinase 1 (PLK1), a member of the serine/threonine kinase family that plays an important role in regulating the mitotic and meiotic cell cycle. The phosphorylation of specific substrates mediated by PLK1 controls nuclear envelope breakdown (NEBD), centrosome maturation, proper spindle assembly, chromosome segregation, and cytokinesis. In mammalian oogenesis, PLK1 is essential for resuming meiosis before ovulation and for establishing the meiotic spindle. Among other potential roles, PLK1 regulates the localized translation of spindle-enriched mRNAs by phosphorylating and thereby inhibiting the translational repressor 4E-BP1, a downstream target of the mTOR (mammalian target of rapamycin) pathway. In this review, we summarize the functions of PLK1 in mitosis, meiosis, and cytokinesis and focus on the role of PLK1 in regulating mRNA translation. However, knowledge of the role of PLK1 in the regulation of meiosis remains limited.
- Klíčová slova
- PLK1, mRNA translation, meiosis, mitosis, oocytes, polo-like kinase 1, spindle,
- MeSH
- lidé MeSH
- meióza MeSH
- mitóza MeSH
- polo-like kinasa 1 MeSH
- protein-serin-threoninkinasy * metabolismus MeSH
- proteiny buněčného cyklu * metabolismus MeSH
- protoonkogenní proteiny metabolismus MeSH
- Check Tag
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
- Názvy látek
- protein-serin-threoninkinasy * MeSH
- proteiny buněčného cyklu * MeSH
- protoonkogenní proteiny MeSH
The developmental potential of porcine oocytes cultured in vitro was remarkably enhanced in a medium containing FGF2, LIF and IGF1 (FLI) when compared to a medium supplemented with gonadotropins and EGF (control). We analyzed the molecular background of the enhanced oocyte quality by comparing the time course of MAPK3/1 and AKT activation, and the expression of genes controlled by these kinases in cumulus-oocyte complexes (COCs) cultured in FLI and the control medium. The pattern of MAPK3/1 activation in COCs was very similar in both media, except for a robust increase in MAPK3/1 phosphorylation during the first hour of culture in the FLI medium. The COCs cultured in the FLI medium exhibited significantly higher activity of AKT than in the control medium from the beginning up to 16 h of culture; afterwards a deregulation of AKT activity occurred in the FLI medium, which was not observed in the control medium. The expression of cumulus cell genes controlled by both kinases was also modulated in the FLI medium, and in particular the genes related to cumulus-expansion, signaling, apoptosis, antioxidants, cell-to-cell communication, proliferation, and translation were significantly overexpressed. Collectively, these data indicate that both MAPK3/1 and AKT are implicated in the enhanced quality of oocytes cultured in FLI medium.
- Klíčová slova
- AKT kinase, FGF2, IGF1, LIF, MAP kinase 3/1, gene expression, oocyte competence, oocyte maturation,
- MeSH
- IVM techniky metody veterinární MeSH
- kultivační média chemie farmakologie MeSH
- kultivované buňky MeSH
- meióza účinky léků fyziologie MeSH
- mitogenem aktivovaná proteinkinasa 1 fyziologie MeSH
- mitogenem aktivovaná proteinkinasa 3 fyziologie MeSH
- oocyty cytologie účinky léků fyziologie MeSH
- oogeneze účinky léků fyziologie MeSH
- prasata MeSH
- protoonkogenní proteiny c-akt fyziologie MeSH
- signální transdukce účinky léků fyziologie MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- kultivační média MeSH
- mitogenem aktivovaná proteinkinasa 1 MeSH
- mitogenem aktivovaná proteinkinasa 3 MeSH
- protoonkogenní proteiny c-akt MeSH
Fully grown mammalian oocytes utilize transcripts synthetized and stored during earlier development. RNA localization followed by a local translation is a mechanism responsible for the regulation of spatial and temporal gene expression. Here we show that the mouse oocyte contains 3 forms of cap-dependent translational repressor expressed on the mRNA level: 4E-BP1, 4E-BP2 and 4E-BP3. However, only 4E-BP1 is present as a protein in oocytes, it becomes inactivated by phosphorylation after nuclear envelope breakdown and as such it promotes cap-dependent translation after NEBD. Phosphorylation of 4E-BP1 can be seen in the oocytes after resumption of meiosis but it is not detected in the surrounding cumulus cells, indicating that 4E-BP1 promotes translation at a specific cell cycle stage. Our immunofluorescence analyses of 4E-BP1 in oocytes during meiosis I showed an even localization of global 4E-BP1, as well as of its 4E-BP1 (Thr37/46) phosphorylated form. On the other hand, 4E-BP1 phosphorylated on Ser65 is localized at the spindle poles, and 4E-BP1 phosphorylated on Thr70 localizes on the spindle. We further show that the main positive regulators of 4E-BP1 phosphorylation after NEBD are mTOR and CDK1 kinases, but not PLK1 kinase. CDK1 exerts its activity toward 4E-BP1 phosphorylation via phosphorylation and activation of mTOR. Moreover, both CDK1 and phosphorylated mTOR co-localize with 4E-BP1 phosphorylated on Thr70 on the spindle at the onset of meiotic resumption. Expression of the dominant negative 4E-BP1 mutant adversely affects translation and results in spindle abnormality. Taken together, our results show that the phosphorylation of 4E-BP1 promotes translation at the onset of meiosis to support the spindle assembly and suggest an important role of CDK1 and mTOR kinases in this process. We also show that the mTOR regulatory pathway is present in human oocytes and is likely to function in a similar way as in mouse oocytes.
- Klíčová slova
- 4E-BP1, CDK1, cumulus cells, kinase, mRNA, mTOR, meiosis, oocyte, spindle, translation,
- MeSH
- adaptorové proteiny signální transdukční MeSH
- aparát dělícího vřeténka genetika MeSH
- buněčný cyklus genetika MeSH
- eukaryotické iniciační faktory MeSH
- fosfoproteiny genetika metabolismus MeSH
- fosforylace MeSH
- lidé MeSH
- myši MeSH
- oocyty růst a vývoj metabolismus MeSH
- proteinkinasa CDC2 genetika MeSH
- proteiny buněčného cyklu MeSH
- proteosyntéza MeSH
- TOR serin-threoninkinasy genetika MeSH
- transportní proteiny genetika metabolismus MeSH
- vývojová regulace genové exprese MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- adaptorové proteiny signální transdukční MeSH
- Eif4ebp1 protein, mouse MeSH Prohlížeč
- eukaryotické iniciační faktory MeSH
- fosfoproteiny MeSH
- mTOR protein, mouse MeSH Prohlížeč
- proteinkinasa CDC2 MeSH
- proteiny buněčného cyklu MeSH
- TOR serin-threoninkinasy MeSH
- transportní proteiny MeSH
Hydrogen sulfide (H2S) has been revealed to be a signal molecule with second messenger action in the somatic cells of many tissues, including the reproductive tract. The aim of this study was to address how exogenous H2S acts on the meiotic maturation of porcine oocytes, including key maturation factors such as MPF and MAPK, and cumulus expansion intensity of cumulus-oocyte complexes. We observed that the H2S donor, Na2S, accelerated oocyte in vitro maturation in a dose-dependent manner, following an increase of MPF activity around germinal vesicle breakdown. Concurrently, the H2S donor affected cumulus expansion, monitored by hyaluronic acid production. Our results suggest that the H2S donor influences oocyte maturation and thus also participates in the regulation of cumulus expansion. The exogenous H2S donor apparently affects key signal pathways of oocyte maturation and cumulus expansion, resulting in faster oocyte maturation with little need of cumulus expansion.
- MeSH
- extracelulárním signálem regulované MAP kinasy metabolismus MeSH
- faktor podporující zrání metabolismus MeSH
- gasotransmitery farmakologie MeSH
- kokultivační techniky MeSH
- kultivované buňky MeSH
- kumulární buňky cytologie metabolismus MeSH
- meióza účinky léků MeSH
- oocyty cytologie metabolismus MeSH
- prasata MeSH
- sulfan farmakologie MeSH
- sulfidy farmakologie MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- extracelulárním signálem regulované MAP kinasy MeSH
- faktor podporující zrání MeSH
- gasotransmitery MeSH
- sodium sulfide MeSH Prohlížeč
- sulfan MeSH
- sulfidy MeSH