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Iyyappan R, Aleshkina D, Ming H, Dvoran M, Kakavand K, Jansova D, del Llano E, Gahurova L, Bruce AW, Masek T, Pospisek M, Horvat F, Kubelka M, Jiang Z, Susor A. The translational oscillation in oocyte and early embryo development. Nucleic Acids Res 2023; 51:12076-12091. [PMID: 37950888 PMCID: PMC10711566 DOI: 10.1093/nar/gkad996] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 10/03/2023] [Accepted: 10/17/2023] [Indexed: 11/13/2023] Open
Abstract
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.
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Affiliation(s)
- Rajan Iyyappan
- Laboratory of Biochemistry and Molecular Biology of Germ Cells, Institute of Animal Physiology and Genetics of the Czech Academy of Sciences, Rumburska 89, 277 21 Libechov, Czech Republic
| | - Daria Aleshkina
- Laboratory of Biochemistry and Molecular Biology of Germ Cells, Institute of Animal Physiology and Genetics of the Czech Academy of Sciences, Rumburska 89, 277 21 Libechov, Czech Republic
| | - Hao Ming
- Department of Animal Sciences, University of Florida, Gainesville, FL 32610, USA
| | - Michal Dvoran
- Laboratory of Biochemistry and Molecular Biology of Germ Cells, Institute of Animal Physiology and Genetics of the Czech Academy of Sciences, Rumburska 89, 277 21 Libechov, Czech Republic
| | - Kianoush Kakavand
- Laboratory of Biochemistry and Molecular Biology of Germ Cells, Institute of Animal Physiology and Genetics of the Czech Academy of Sciences, Rumburska 89, 277 21 Libechov, Czech Republic
| | - Denisa Jansova
- Laboratory of Biochemistry and Molecular Biology of Germ Cells, Institute of Animal Physiology and Genetics of the Czech Academy of Sciences, Rumburska 89, 277 21 Libechov, Czech Republic
| | - Edgar del Llano
- Laboratory of Biochemistry and Molecular Biology of Germ Cells, Institute of Animal Physiology and Genetics of the Czech Academy of Sciences, Rumburska 89, 277 21 Libechov, Czech Republic
| | - Lenka Gahurova
- Laboratory of Biochemistry and Molecular Biology of Germ Cells, Institute of Animal Physiology and Genetics of the Czech Academy of Sciences, Rumburska 89, 277 21 Libechov, Czech Republic
| | - Alexander W Bruce
- Laboratory of Early Mammalian Developmental Biology, Department of Molecular Biology & Genetics, Faculty of Science, University of South Bohemia in České Budějovice, Branisovšká 31a, České Budějovice, Czech Republic
| | - Tomas Masek
- Laboratory of RNA Biochemistry, Department of Genetics and Microbiology, Faculty of Science, Charles University, Viničná 5, 128 44 Prague 2, Czech Republic
| | - Martin Pospisek
- Laboratory of RNA Biochemistry, Department of Genetics and Microbiology, Faculty of Science, Charles University, Viničná 5, 128 44 Prague 2, Czech Republic
| | - Filip Horvat
- Laboratory of Epigenetic Regulations, Institute of Molecular Genetics of the Czech Academy of Sciences, Videnska 1083, 142 20 Prague 4, Czech Republic
- Bioinformatics Group, Division of Molecular Biology, Department of Biology, Faculty of Science, University of Zagreb, 10000, Zagreb, Croatia
| | - Michal Kubelka
- Laboratory of Biochemistry and Molecular Biology of Germ Cells, Institute of Animal Physiology and Genetics of the Czech Academy of Sciences, Rumburska 89, 277 21 Libechov, Czech Republic
| | - Zongliang Jiang
- Department of Animal Sciences, University of Florida, Gainesville, FL 32610, USA
| | - Andrej Susor
- Laboratory of Biochemistry and Molecular Biology of Germ Cells, Institute of Animal Physiology and Genetics of the Czech Academy of Sciences, Rumburska 89, 277 21 Libechov, Czech Republic
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Gahurova L, Tomankova J, Cerna P, Bora P, Kubickova M, Virnicchi G, Kovacovicova K, Potesil D, Hruska P, Zdrahal Z, Anger M, Susor A, Bruce AW. Spatial positioning of preimplantation mouse embryo cells is regulated by mTORC1 and m 7G-cap-dependent translation at the 8- to 16-cell transition. Open Biol 2023; 13:230081. [PMID: 37553074 PMCID: PMC10409569 DOI: 10.1098/rsob.230081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Accepted: 07/18/2023] [Indexed: 08/10/2023] Open
Abstract
Preimplantation mouse embryo development involves temporal-spatial specification and segregation of three blastocyst cell lineages: trophectoderm, primitive endoderm and epiblast. Spatial separation of the outer-trophectoderm lineage from the two other inner-cell-mass (ICM) lineages starts with the 8- to 16-cell transition and concludes at the 32-cell stages. Accordingly, the ICM is derived from primary and secondary contributed cells; with debated relative EPI versus PrE potencies. We report generation of primary but not secondary ICM populations is highly dependent on temporal activation of mammalian target of Rapamycin (mTOR) during 8-cell stage M-phase entry, mediated via regulation of the 7-methylguanosine-cap (m7G-cap)-binding initiation complex (EIF4F) and linked to translation of mRNAs containing 5' UTR terminal oligopyrimidine (TOP-) sequence motifs, as knockdown of identified TOP-like motif transcripts impairs generation of primary ICM founders. However, mTOR inhibition-induced ICM cell number deficits in early blastocysts can be compensated by the late blastocyst stage, after inhibitor withdrawal; compensation likely initiated at the 32-cell stage when supernumerary outer cells exhibit molecular characteristics of inner cells. These data identify a novel mechanism specifically governing initial spatial segregation of mouse embryo blastomeres, that is distinct from those directing subsequent inner cell formation, contributing to germane segregation of late blastocyst lineages.
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Affiliation(s)
- Lenka Gahurova
- Laboratory of Early Mammalian Developmental Biology (LEMDB), Department of Molecular Biology and Genetics, Faculty of Science, University of South Bohemia, Branišovská 31, 37005 České Budějovice, Czech Republic
- Laboratory of Biochemistry and Molecular Biology of Germ Cells, Institute of Animal Physiology and Genetics, Czech Academy of Sciences, Rumburská 89, 27721 Liběchov, Czech Republic
| | - Jana Tomankova
- Laboratory of Early Mammalian Developmental Biology (LEMDB), Department of Molecular Biology and Genetics, Faculty of Science, University of South Bohemia, Branišovská 31, 37005 České Budějovice, Czech Republic
| | - Pavlina Cerna
- Laboratory of Early Mammalian Developmental Biology (LEMDB), Department of Molecular Biology and Genetics, Faculty of Science, University of South Bohemia, Branišovská 31, 37005 České Budějovice, Czech Republic
| | - Pablo Bora
- Laboratory of Early Mammalian Developmental Biology (LEMDB), Department of Molecular Biology and Genetics, Faculty of Science, University of South Bohemia, Branišovská 31, 37005 České Budějovice, Czech Republic
| | - Michaela Kubickova
- Laboratory of Early Mammalian Developmental Biology (LEMDB), Department of Molecular Biology and Genetics, Faculty of Science, University of South Bohemia, Branišovská 31, 37005 České Budějovice, Czech Republic
| | - Giorgio Virnicchi
- Laboratory of Early Mammalian Developmental Biology (LEMDB), Department of Molecular Biology and Genetics, Faculty of Science, University of South Bohemia, Branišovská 31, 37005 České Budějovice, Czech Republic
| | - Kristina Kovacovicova
- Laboratory of Cell Division Control, Institute of Animal Physiology and Genetics, Czech Academy of Sciences, Rumburská 89, 27721 Liběchov, Czech Republic
- Department of Genetics and Reproduction, Central European Institute of Technology, Veterinary Research Institute, Hudcova 296/70, 621 00 Brno, Czech Republic
| | - David Potesil
- Laboratory of Functional Genomics and Proteomics, National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Kamenice 753/5, 62500 Brno, Czech Republic
| | - Pavel Hruska
- Laboratory of Functional Genomics and Proteomics, National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Kamenice 753/5, 62500 Brno, Czech Republic
| | - Zbynek Zdrahal
- Laboratory of Functional Genomics and Proteomics, National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Kamenice 753/5, 62500 Brno, Czech Republic
- Central European Institute of Technology, Masaryk University, Kamenice 753/5, 62500 Brno, Czech Republic
| | - Martin Anger
- Laboratory of Cell Division Control, Institute of Animal Physiology and Genetics, Czech Academy of Sciences, Rumburská 89, 27721 Liběchov, Czech Republic
- Department of Genetics and Reproduction, Central European Institute of Technology, Veterinary Research Institute, Hudcova 296/70, 621 00 Brno, Czech Republic
| | - Andrej Susor
- Laboratory of Biochemistry and Molecular Biology of Germ Cells, Institute of Animal Physiology and Genetics, Czech Academy of Sciences, Rumburská 89, 27721 Liběchov, Czech Republic
| | - Alexander W. Bruce
- Laboratory of Early Mammalian Developmental Biology (LEMDB), Department of Molecular Biology and Genetics, Faculty of Science, University of South Bohemia, Branišovská 31, 37005 České Budějovice, Czech Republic
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Kalous J, Aleshkina D, Anger M. A Role of PI3K/Akt Signaling in Oocyte Maturation and Early Embryo Development. Cells 2023; 12:1830. [PMID: 37508495 PMCID: PMC10378481 DOI: 10.3390/cells12141830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 06/24/2023] [Accepted: 07/06/2023] [Indexed: 07/30/2023] Open
Abstract
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.
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Affiliation(s)
- Jaroslav Kalous
- Institute of Animal Physiology and Genetics, Academy of Sciences of the Czech Republic, 277 21 Libechov, Czech Republic
| | - Daria Aleshkina
- Institute of Animal Physiology and Genetics, Academy of Sciences of the Czech Republic, 277 21 Libechov, Czech Republic
- Department of Cell Biology, Faculty of Science, Charles University, Albertov 6, 128 00 Praha, Czech Republic
| | - Martin Anger
- Institute of Animal Physiology and Genetics, Academy of Sciences of the Czech Republic, 277 21 Libechov, Czech Republic
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Jiang Y, Adhikari D, Li C, Zhou X. Spatiotemporal regulation of maternal mRNAs during vertebrate oocyte meiotic maturation. Biol Rev Camb Philos Soc 2023; 98:900-930. [PMID: 36718948 DOI: 10.1111/brv.12937] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Revised: 01/15/2023] [Accepted: 01/17/2023] [Indexed: 02/01/2023]
Abstract
Vertebrate oocytes face a particular challenge concerning the regulation of gene expression during meiotic maturation. Global transcription becomes quiescent in fully grown oocytes, remains halted throughout maturation and fertilization, and only resumes upon embryonic genome activation. Hence, the oocyte meiotic maturation process is largely regulated by protein synthesis from pre-existing maternal messenger RNAs (mRNAs) that are transcribed and stored during oocyte growth. Rapidly developing genome-wide techniques have greatly expanded our insights into the global translation changes and possible regulatory mechanisms during oocyte maturation. The storage, translation, and processing of maternal mRNAs are thought to be regulated by factors interacting with elements in the mRNA molecules. Additionally, posttranscriptional modifications of mRNAs, such as methylation and uridylation, have recently been demonstrated to play crucial roles in maternal mRNA destabilization. However, a comprehensive understanding of the machineries that regulate maternal mRNA fate during oocyte maturation is still lacking. In particular, how the transcripts of important cell cycle components are stabilized, recruited at the appropriate time for translation, and eliminated to modulate oocyte meiotic progression remains unclear. A better understanding of these mechanisms will provide invaluable insights for the preconditions of developmental competence acquisition, with important implications for the treatment of infertility. This review discusses how the storage, localization, translation, and processing of oocyte mRNAs are regulated, and how these contribute to oocyte maturation progression.
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Affiliation(s)
- Yanwen Jiang
- College of Animal Science, Jilin University, 5333 Xian Road, Changchun, 130062, China
| | - Deepak Adhikari
- Department of Anatomy and Developmental Biology, Monash Biomedicine Discovery Institute, Monash University, 19 Innovation Walk, Melbourne, VIC, 3800, Australia
| | - Chunjin Li
- College of Animal Science, Jilin University, 5333 Xian Road, Changchun, 130062, China
| | - Xu Zhou
- College of Animal Science, Jilin University, 5333 Xian Road, Changchun, 130062, China
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5
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Kalous J, Aleshkina D. Multiple Roles of PLK1 in Mitosis and Meiosis. Cells 2023; 12:cells12010187. [PMID: 36611980 PMCID: PMC9818836 DOI: 10.3390/cells12010187] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 12/22/2022] [Accepted: 12/23/2022] [Indexed: 01/05/2023] Open
Abstract
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.
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Dvoran M, Nemcova L, Kalous J. An Interplay between Epigenetics and Translation in Oocyte Maturation and Embryo Development: Assisted Reproduction Perspective. Biomedicines 2022; 10:biomedicines10071689. [PMID: 35884994 PMCID: PMC9313063 DOI: 10.3390/biomedicines10071689] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 06/25/2022] [Accepted: 06/28/2022] [Indexed: 12/11/2022] Open
Abstract
Germ cell quality is a key prerequisite for successful fertilization and early embryo development. The quality is determined by the fine regulation of transcriptomic and proteomic profiles, which are prone to alteration by assisted reproduction technology (ART)-introduced in vitro methods. Gaining evidence shows the ART can influence preset epigenetic modifications within cultured oocytes or early embryos and affect their developmental competency. The aim of this review is to describe ART-determined epigenetic changes related to the oogenesis, early embryogenesis, and further in utero development. We confront the latest epigenetic, related epitranscriptomic, and translational regulation findings with the processes of meiotic maturation, fertilization, and early embryogenesis that impact the developmental competency and embryo quality. Post-ART embryo transfer, in utero implantation, and development (placentation, fetal development) are influenced by environmental and lifestyle factors. The review is emphasizing their epigenetic and ART contribution to fetal development. An epigenetic parallel among mouse, porcine, and bovine animal models and human ART is drawn to illustrate possible future mechanisms of infertility management as well as increase the awareness of the underlying mechanisms governing oocyte and embryo developmental complexity under ART conditions.
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Li F, Hu G, Long X, Cao Y, Li Q, Guo W, Wang J, Liu J, Fu S. Stearic Acid Activates the PI3K-mTOR-4EBP1/S6K and mTOR-SREBP-1 Signaling Axes through FATP4-CDK1 To Promote Milk Synthesis in Primary Bovine Mammary Epithelial Cells. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:4007-4018. [PMID: 35333520 DOI: 10.1021/acs.jafc.2c00208] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Stearic acid (SA), an 18-carbon long-chain saturated fatty acid, has great potential for promoting lactation. Therefore, this study investigates the effects and mechanism of SA on milk synthesis in primary bovine mammary epithelial cells (BMECs). In our study, we found that SA significantly increased β-casein and triglycerides, and the effect was most significant at 100 μM. Signaling pathway studies have found that SA affects milk synthesis by upregulating cyclin-dependent kinase 1 (CDK1) to activate PI3K-mTOR-4EBP1/S6K and mTOR-SREBP-1 pathways. Furthermore, we detected fatty acid transport proteins (FATPs) when BMECs were treated with SA; the mRNA levels of FATP3 (3.713 ± 0.583) and FATP4 (40.815 ± 8.959) were significantly upregulated at 100 μM. Subsequently, we constructed FATP4-siRNA and found that SA was transported by FATP4 into BMECs, promoting milk synthesis. Collectively, these results revealed that SA activated PI3K-mTOR-4EBP1/S6K and mTOR-SREBP-1 signaling axes through FATP4-CDK1 to promote milk synthesis in BMECs.
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Affiliation(s)
- Feng Li
- College of Veterinary Medicine, Jilin University, Changchun 130062, China
| | - Guiqiu Hu
- College of Veterinary Medicine, Jilin University, Changchun 130062, China
| | - Xiaoyu Long
- College of Veterinary Medicine, Jilin University, Changchun 130062, China
| | - Yu Cao
- College of Veterinary Medicine, Jilin University, Changchun 130062, China
| | - Qianqian Li
- College of Veterinary Medicine, Jilin University, Changchun 130062, China
| | - Wenjin Guo
- College of Veterinary Medicine, Jilin University, Changchun 130062, China
| | - Jiaxin Wang
- College of Veterinary Medicine, Jilin University, Changchun 130062, China
| | - Juxiong Liu
- College of Veterinary Medicine, Jilin University, Changchun 130062, China
| | - Shoupeng Fu
- College of Veterinary Medicine, Jilin University, Changchun 130062, China
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Amino Acid Transport and Metabolism Regulate Early Embryo Development: Species Differences, Clinical Significance, and Evolutionary Implications. Cells 2021; 10:cells10113154. [PMID: 34831375 PMCID: PMC8618253 DOI: 10.3390/cells10113154] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 11/05/2021] [Accepted: 11/11/2021] [Indexed: 12/11/2022] Open
Abstract
In this review we discuss the beneficial effects of amino acid transport and metabolism on pre- and peri-implantation embryo development, and we consider how disturbances in these processes lead to undesirable health outcomes in adults. Proline, glutamine, glycine, and methionine transport each foster cleavage-stage development, whereas leucine uptake by blastocysts via transport system B0,+ promotes the development of trophoblast motility and the penetration of the uterine epithelium in mammalian species exhibiting invasive implantation. (Amino acid transport systems and transporters, such as B0,+, are often oddly named. The reader is urged to focus on the transporters’ functions, not their names.) B0,+ also accumulates leucine and other amino acids in oocytes of species with noninvasive implantation, thus helping them to produce proteins to support later development. This difference in the timing of the expression of system B0,+ is termed heterochrony—a process employed in evolution. Disturbances in leucine uptake via system B0,+ in blastocysts appear to alter the subsequent development of embryos, fetuses, and placentae, with undesirable consequences for offspring. These consequences may include greater adiposity, cardiovascular dysfunction, hypertension, neural abnormalities, and altered bone growth in adults. Similarly, alterations in amino acid transport and metabolism in pluripotent cells in the blastocyst inner cell mass likely lead to epigenetic DNA and histone modifications that produce unwanted transgenerational health outcomes. Such outcomes might be avoided if we learn more about the mechanisms of these effects.
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Saba JA, Liakath-Ali K, Green R, Watt FM. Translational control of stem cell function. Nat Rev Mol Cell Biol 2021; 22:671-690. [PMID: 34272502 DOI: 10.1038/s41580-021-00386-2] [Citation(s) in RCA: 60] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/27/2021] [Indexed: 12/22/2022]
Abstract
Stem cells are characterized by their ability to self-renew and differentiate into many different cell types. Research has focused primarily on how these processes are regulated at a transcriptional level. However, recent studies have indicated that stem cell behaviour is strongly coupled to the regulation of protein synthesis by the ribosome. In this Review, we discuss how different translation mechanisms control the function of adult and embryonic stem cells. Stem cells are characterized by low global translation rates despite high levels of ribosome biogenesis. The maintenance of pluripotency, the commitment to a specific cell fate and the switch to cell differentiation depend on the tight regulation of protein synthesis and ribosome biogenesis. Translation regulatory mechanisms that impact on stem cell function include mTOR signalling, ribosome levels, and mRNA and tRNA features and amounts. Understanding these mechanisms important for stem cell self-renewal and differentiation may also guide our understanding of cancer grade and metastasis.
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Affiliation(s)
- James A Saba
- Department of Molecular Biology and Genetics, Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Kifayathullah Liakath-Ali
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
| | - Rachel Green
- Department of Molecular Biology and Genetics, Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
| | - Fiona M Watt
- King's College London Centre for Stem Cells and Regenerative Medicine, Guy's Hospital, London, UK.
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Jansova D, Aleshkina D, Jindrova A, Iyyappan R, An Q, Fan G, Susor A. Single Molecule RNA Localization and Translation in the Mammalian Oocyte and Embryo. J Mol Biol 2021; 433:167166. [PMID: 34293340 DOI: 10.1016/j.jmb.2021.167166] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 06/29/2021] [Accepted: 07/13/2021] [Indexed: 11/28/2022]
Abstract
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.
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Affiliation(s)
- Denisa Jansova
- Institute of Animal Physiology and Genetics, Czech Academy of Sciences, Libechov 277 21, Czech Republic.
| | - Daria Aleshkina
- Institute of Animal Physiology and Genetics, Czech Academy of Sciences, Libechov 277 21, Czech Republic
| | - Anna Jindrova
- Institute of Animal Physiology and Genetics, Czech Academy of Sciences, Libechov 277 21, Czech Republic
| | - Rajan Iyyappan
- Institute of Animal Physiology and Genetics, Czech Academy of Sciences, Libechov 277 21, Czech Republic
| | - Qin An
- Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, CA 90095-7088, USA
| | - Guoping Fan
- Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, CA 90095-7088, USA
| | - Andrej Susor
- Institute of Animal Physiology and Genetics, Czech Academy of Sciences, Libechov 277 21, Czech Republic.
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11
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Still Living Better through Chemistry: An Update on Caloric Restriction and Caloric Restriction Mimetics as Tools to Promote Health and Lifespan. Int J Mol Sci 2020; 21:ijms21239220. [PMID: 33287232 PMCID: PMC7729921 DOI: 10.3390/ijms21239220] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Revised: 11/30/2020] [Accepted: 11/30/2020] [Indexed: 02/06/2023] Open
Abstract
Caloric restriction (CR), the reduction of caloric intake without inducing malnutrition, is the most reproducible method of extending health and lifespan across numerous organisms, including humans. However, with nearly one-third of the world’s population overweight, it is obvious that caloric restriction approaches are difficult for individuals to achieve. Therefore, identifying compounds that mimic CR is desirable to promote longer, healthier lifespans without the rigors of restricting diet. Many compounds, such as rapamycin (and its derivatives), metformin, or other naturally occurring products in our diets (nutraceuticals), induce CR-like states in laboratory models. An alternative to CR is the removal of specific elements (such as individual amino acids) from the diet. Despite our increasing knowledge of the multitude of CR approaches and CR mimetics, the extent to which these strategies overlap mechanistically remains unclear. Here we provide an update of CR and CR mimetic research, summarizing mechanisms by which these strategies influence genome function required to treat age-related pathologies and identify the molecular fountain of youth.
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Zamfirescu RC, Day ML, Morris MB. mTORC1/2 signaling is downregulated by amino acid-free culture of mouse preimplantation embryos and is only partially restored by amino acid readdition. Am J Physiol Cell Physiol 2020; 320:C30-C44. [PMID: 33052068 DOI: 10.1152/ajpcell.00385.2020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Development of the mammalian preimplantation embryo is influenced by autocrine/paracrine factors and the availability of nutrients. Deficiencies of these during in vitro culture reduce the success of assisted reproductive technologies. The mechanistic target of rapamycin complex 1 (mTORC1) pathway integrates external and internal signals, including those by amino acids (AAs), to promote normal preimplantation development. For this reason, AAs are often included in embryo culture media. In this study, we examined how withdrawal and addition of AAs to culture media modulate mTORC1 pathway activity compared with its activity in mouse embryos developed in vivo. Phosphorylation of signaling components downstream of mTORC1, namely, p70 ribosomal protein S6 kinase (p70S6K), ribosomal protein S6, and 4E binding protein 1 (4E-BP1), and that of protein kinase B (Akt), which lies upstream of mTORC1, changed significantly across stages of embryos developed in vivo. For freshly isolated blastocysts placed in vitro, the absence of AAs in the culture medium, even for a few hours, decreased mTORC1 signaling, which could only be partially restored by their addition. Long-term culture of early embryos to blastocysts in the absence of AAs decreased mTORC1 signaling to a greater extent and again this could only be partially restored by their inclusion. This failure to fully restore is probably due to decreased phosphatidylinositol 3-kinase (PI3K)/Akt/mTORC2 signaling in culture, as indicated by decreased P-AktS473. mTORC2 lies upstream of mTORC1 and is insensitive to AAs, and its reduced activity probably results from loss of maternal/autocrine factors. These data highlight reduced mTORC1/2 signaling activity correlating with compromised development in vitro and show that the addition of AAs can only partially offset these effects.
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Affiliation(s)
- Radu C Zamfirescu
- Discipline of Physiology and Bosch Institute, Faculty of Medicine and Health, School of Medical Sciences, The University of Sydney, Camperdown, New South Wales, Australia
| | - Margot L Day
- Discipline of Physiology and Bosch Institute, Faculty of Medicine and Health, School of Medical Sciences, The University of Sydney, Camperdown, New South Wales, Australia
| | - Michael B Morris
- Discipline of Physiology and Bosch Institute, Faculty of Medicine and Health, School of Medical Sciences, The University of Sydney, Camperdown, New South Wales, Australia
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13
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Tetkova A, Susor A, Kubelka M, Nemcova L, Jansova D, Dvoran M, Del Llano E, Holubcova Z, Kalous J. Follicle-stimulating hormone administration affects amino acid metabolism in mammalian oocytes†. Biol Reprod 2020; 101:719-732. [PMID: 31290535 DOI: 10.1093/biolre/ioz117] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Revised: 06/18/2019] [Accepted: 07/04/2019] [Indexed: 12/27/2022] Open
Abstract
Culture media used in assisted reproduction are commonly supplemented with gonadotropin hormones to support the nuclear and cytoplasmic maturation of in vitro matured oocytes. However, the effect of gonadotropins on protein synthesis in oocytes is yet to be fully understood. As published data have previously documented a positive in vitro effect of follicle-stimulating hormone (FSH) on cytoplasmic maturation, we exposed mouse denuded oocytes to FSH in order to evaluate the changes in global protein synthesis. We found that dose-dependent administration of FSH resulted in a decrease of methionine incorporation into de novo synthesized proteins in denuded mouse oocytes and oocytes cultured in cumulus-oocyte complexes. Similarly, FSH influenced methionine incorporation in additional mammalian species including human. Furthermore, we showed the expression of FSH-receptor protein in oocytes. We found that major translational regulators were not affected by FSH treatment; however, the amino acid uptake became impaired. We propose that the effect of FSH treatment on amino acid uptake is influenced by FSH receptor with the effect on oocyte metabolism and physiology.
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Affiliation(s)
- Anna Tetkova
- Institute of Animal Physiology and Genetics, Czech Academy of Science, Libechov, Czech Republic.,Department of Cell Biology, Faculty of Science, Charles University in Prague, Prague 2, Czech Republic
| | - Andrej Susor
- Institute of Animal Physiology and Genetics, Czech Academy of Science, Libechov, Czech Republic
| | - Michal Kubelka
- Institute of Animal Physiology and Genetics, Czech Academy of Science, Libechov, Czech Republic
| | - Lucie Nemcova
- Institute of Animal Physiology and Genetics, Czech Academy of Science, Libechov, Czech Republic
| | - Denisa Jansova
- Institute of Animal Physiology and Genetics, Czech Academy of Science, Libechov, Czech Republic
| | - Michal Dvoran
- Institute of Animal Physiology and Genetics, Czech Academy of Science, Libechov, Czech Republic.,Department of Cell Biology, Faculty of Science, Charles University in Prague, Prague 2, Czech Republic
| | - Edgar Del Llano
- Institute of Animal Physiology and Genetics, Czech Academy of Science, Libechov, Czech Republic.,Department of Cell Biology, Faculty of Science, Charles University in Prague, Prague 2, Czech Republic
| | - Zuzana Holubcova
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, Brno, Czech Republic.,Reprofit International, Clinic of Reproductive Medicine, Brno, Czech Republic
| | - Jaroslav Kalous
- Institute of Animal Physiology and Genetics, Czech Academy of Science, Libechov, Czech Republic
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14
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Camlin NJ, Evans JP. Auxin-inducible protein degradation as a novel approach for protein depletion and reverse genetic discoveries in mammalian oocytes†. Biol Reprod 2020; 101:704-718. [PMID: 31299080 PMCID: PMC6863966 DOI: 10.1093/biolre/ioz113] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2019] [Revised: 05/25/2019] [Accepted: 07/10/2019] [Indexed: 01/06/2023] Open
Abstract
The disruption of protein expression is a major approach used for investigating protein function in mammalian oocytes. This is often achieved with RNAi/morpholino-mediated knockdown or gene knockout, leading to long-term loss of proteins of interest. However, these methods have noteworthy limitations, including (a) slow protein turnover can prohibit use of these approaches; (b) essential roles in early events precludes characterization of functions in subsequent events; (c) extended protein loss can allow time for compensatory mechanisms and other unanticipated events that confound interpretation of results. The work presented here examines the use of auxin-inducible degradation, a powerful new approach that overcomes these limitations through the depletion of one's protein of interest through controllable ubiquitin-mediated degradation. This method has been employed in yeast and mammalian cell lines, and here we demonstrate the utility of auxin-inducible degradation in mouse oocytes at multiple stages of meiosis, through degradation of exogenously expressed EGFP. We also evaluate important parameters for experimental design for use of this system in oocytes. This study thus expands the toolkit of researchers in oocyte biology, establishing the use of this unique and versatile approach for depleting proteins in oocytes, and providing researchers with valuable information to make use of this system.
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Affiliation(s)
- Nicole J Camlin
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, USA
| | - Janice P Evans
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, USA
- Correspondence: Department of Biological Sciences, Purdue University, 915 W. State St., West Lafayette, IN 47907. Tel: +765-494-4407; Fax: (765) 496–1495; E-mail:
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15
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Kalous J, Jansová D, Šušor A. Role of Cyclin-Dependent Kinase 1 in Translational Regulation in the M-Phase. Cells 2020; 9:cells9071568. [PMID: 32605021 PMCID: PMC7408968 DOI: 10.3390/cells9071568] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 06/15/2020] [Accepted: 06/24/2020] [Indexed: 12/20/2022] Open
Abstract
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.
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16
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Zhang J, Zhang YL, Zhao LW, Pi SB, Zhang SY, Tong C, Fan HY. The CRL4-DCAF13 ubiquitin E3 ligase supports oocyte meiotic resumption by targeting PTEN degradation. Cell Mol Life Sci 2020; 77:2181-2197. [PMID: 31492966 PMCID: PMC11105099 DOI: 10.1007/s00018-019-03280-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 07/31/2019] [Accepted: 08/12/2019] [Indexed: 12/21/2022]
Abstract
Cullin ring-finger ubiquitin ligase 4 (CRL4) has multiple functions in the maintenance of oocyte survival and meiotic cell cycle progression. DCAF13, a novel CRL4 adaptor, is essential for oocyte development. But the mechanisms by which CRL4-DCAF13 supports meiotic maturation remained unclear. In this study, we demonstrated that DCAF13 stimulates the meiotic resumption-coupled activation of protein synthesis in oocytes, partially by maintaining the activity of PI3K signaling pathway. CRL4-DCAF13 targets the polyubiquitination and degradation of PTEN, a lipid phosphatase that inhibits PI3K pathway as well as oocyte growth and maturation. Dcaf13 knockout in oocytes caused decreased CDK1 activity and impaired meiotic cell cycle progression and chromosome condensation defects. As a result, chromosomes fail to be aligned at the spindle equatorial plate, the spindle assembly checkpoint is activated, and most Dcaf13 null oocytes are arrested at the prometaphase I. The DCAF13-dependent PTEN degradation mechanism fits in as a missing link between CRL4 ubiquitin E3 ligase and PI3K pathway, both of which are crucial for translational activation during oocyte GV-MII transition.
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Affiliation(s)
- Jue Zhang
- MOE Key Laboratory for Biosystems Homeostasis and Protection and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, 866 Yu Hang Tang Rd., Hangzhou, 310058, China
| | - Yin-Li Zhang
- Key Laboratory of Reproductive Dysfunction Management of Zhejiang Province; Assisted Reproduction Unit, Department of Obstetrics and Gynecology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, 310016, China
| | - Long-Wen Zhao
- MOE Key Laboratory for Biosystems Homeostasis and Protection and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, 866 Yu Hang Tang Rd., Hangzhou, 310058, China
| | - Shuai-Bo Pi
- MOE Key Laboratory for Biosystems Homeostasis and Protection and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, 866 Yu Hang Tang Rd., Hangzhou, 310058, China
| | - Song-Ying Zhang
- Key Laboratory of Reproductive Dysfunction Management of Zhejiang Province; Assisted Reproduction Unit, Department of Obstetrics and Gynecology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, 310016, China
| | - Chao Tong
- MOE Key Laboratory for Biosystems Homeostasis and Protection and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, 866 Yu Hang Tang Rd., Hangzhou, 310058, China
| | - Heng-Yu Fan
- Key Laboratory of Reproductive Dysfunction Management of Zhejiang Province; Assisted Reproduction Unit, Department of Obstetrics and Gynecology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, 310016, China.
- MOE Key Laboratory for Biosystems Homeostasis and Protection and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, 866 Yu Hang Tang Rd., Hangzhou, 310058, China.
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17
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Christou-Kent M, Dhellemmes M, Lambert E, Ray PF, Arnoult C. Diversity of RNA-Binding Proteins Modulating Post-Transcriptional Regulation of Protein Expression in the Maturing Mammalian Oocyte. Cells 2020; 9:cells9030662. [PMID: 32182827 PMCID: PMC7140715 DOI: 10.3390/cells9030662] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2020] [Revised: 03/02/2020] [Accepted: 03/03/2020] [Indexed: 12/18/2022] Open
Abstract
The oocyte faces a particular challenge in terms of gene regulation. When oocytes resume meiosis at the end of the growth phase and prior to ovulation, the condensed chromatin state prevents the transcription of genes as they are required. Transcription is effectively silenced from the late germinal vesicle (GV) stage until embryonic genome activation (EGA) following fertilisation. Therefore, during its growth, the oocyte must produce the mRNA transcripts needed to fulfil its protein requirements during the active period of meiotic completion, fertilisation, and the maternal-to zygote-transition (MZT). After meiotic resumption, gene expression control can be said to be transferred from the nucleus to the cytoplasm, from transcriptional regulation to translational regulation. Maternal RNA-binding proteins (RBPs) are the mediators of translational regulation and their role in oocyte maturation and early embryo development is vital. Understanding these mechanisms will provide invaluable insight into the oocyte's requirements for developmental competence, with important implications for the diagnosis and treatment of certain types of infertility. Here, we give an overview of post-transcriptional regulation in the oocyte, emphasising the current knowledge of mammalian RBP mechanisms, and develop the roles of these mechanisms in the timely activation and elimination of maternal transcripts.
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Affiliation(s)
- Marie Christou-Kent
- Université Grenoble Alpes, F-38000 Grenoble, France; (M.C.-K.); (M.D.); (E.L.); (P.F.R.)
- Institute for Advanced Biosciences INSERM U1209, CNRS UMR5309, F-38000 Grenoble, France
| | - Magali Dhellemmes
- Université Grenoble Alpes, F-38000 Grenoble, France; (M.C.-K.); (M.D.); (E.L.); (P.F.R.)
- Institute for Advanced Biosciences INSERM U1209, CNRS UMR5309, F-38000 Grenoble, France
| | - Emeline Lambert
- Université Grenoble Alpes, F-38000 Grenoble, France; (M.C.-K.); (M.D.); (E.L.); (P.F.R.)
- Institute for Advanced Biosciences INSERM U1209, CNRS UMR5309, F-38000 Grenoble, France
| | - Pierre F. Ray
- Université Grenoble Alpes, F-38000 Grenoble, France; (M.C.-K.); (M.D.); (E.L.); (P.F.R.)
- Institute for Advanced Biosciences INSERM U1209, CNRS UMR5309, F-38000 Grenoble, France
- CHU de Grenoble, UM GI-DPI, F-38000 Grenoble, France
| | - Christophe Arnoult
- Université Grenoble Alpes, F-38000 Grenoble, France; (M.C.-K.); (M.D.); (E.L.); (P.F.R.)
- Institute for Advanced Biosciences INSERM U1209, CNRS UMR5309, F-38000 Grenoble, France
- Correspondence: ; Tel.: +33-(0)4-76-63-74-08
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18
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Mitchell DC, Menon A, Garner AL. Cyclin-dependent kinase 4 inhibits the translational repressor 4E-BP1 to promote cap-dependent translation during mitosis-G1 transition. FEBS Lett 2019; 594:1307-1318. [PMID: 31853978 DOI: 10.1002/1873-3468.13721] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 12/02/2019] [Accepted: 12/04/2019] [Indexed: 01/18/2023]
Abstract
Phosphorylation of translational repressor eukaryotic translation initiation factor 4E (eIF4E)-binding protein 1 (4E-BP1) controls the initiation of cap-dependent translation, a type of protein synthesis that is frequently upregulated in human diseases such as cancer. Because of its critical cellular function, it is not surprising that multiple kinases can post-translationally modify 4E-BP1 to drive aberrant cap-dependent translation. We recently reported a site-selective chemoproteomic method for uncovering kinase-substrate interactions, and using this approach, we discovered the cyclin-dependent kinase (CDK)4 as a new 4E-BP1 kinase. Herein, we describe our extension of this work and reveal the role of CDK4 in modulating 4E-BP1 activity in the transition from mitosis to G1, thereby demonstrating a novel role for this kinase in cell cycle regulation.
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Affiliation(s)
- Dylan C Mitchell
- Program in Chemical Biology, University of Michigan, Ann Arbor, MI, USA
| | - Arya Menon
- Department of Medicinal Chemistry, College of Pharmacy, University of Michigan, Ann Arbor, MI, USA
| | - Amanda L Garner
- Program in Chemical Biology, University of Michigan, Ann Arbor, MI, USA.,Department of Medicinal Chemistry, College of Pharmacy, University of Michigan, Ann Arbor, MI, USA
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19
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Sun X, Wei W, Ren J, Liang Y, Wang M, Gui Y, Xue X, Li J, Dai C. Inhibition of 4E-BP1 phosphorylation promotes tubular cell escaping from G2/M arrest and ameliorates kidney fibrosis. Cell Signal 2019; 62:109331. [DOI: 10.1016/j.cellsig.2019.05.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Revised: 05/29/2019] [Accepted: 05/29/2019] [Indexed: 01/17/2023]
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20
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Spatio-temporal expression of ANK2 promotes cytokinesis in oocytes. Sci Rep 2019; 9:13121. [PMID: 31511568 PMCID: PMC6739377 DOI: 10.1038/s41598-019-49483-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Accepted: 08/21/2019] [Indexed: 01/01/2023] Open
Abstract
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.
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21
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Rutkovsky AC, Yeh ES, Guest ST, Findlay VJ, Muise-Helmericks RC, Armeson K, Ethier SP. Eukaryotic initiation factor 4E-binding protein as an oncogene in breast cancer. BMC Cancer 2019; 19:491. [PMID: 31122207 PMCID: PMC6533768 DOI: 10.1186/s12885-019-5667-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Accepted: 05/01/2019] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Eukaryotic Initiation Factor 4E-Binding Protein (EIF4EBP1, 4EBP1) is overexpressed in many human cancers including breast cancer, yet the role of 4EBP1 in breast cancer remains understudied. Despite the known role of 4EBP1 as a negative regulator of cap-dependent protein translation, 4EBP1 is predicted to be an essential driving oncogene in many cancer cell lines in vitro, and can act as a driver of cancer cell proliferation. EIF4EBP1 is located within the 8p11-p12 genomic locus, which is frequently amplified in breast cancer and is known to predict poor prognosis and resistance to endocrine therapy. METHODS Here we evaluated the effect of 4EBP1 targeting using shRNA knock-down of expression of 4EBP1, as well as response to the mTORC targeted drug everolimus in cell lines representing different breast cancer subtypes, including breast cancer cells with the 8p11-p12 amplicon, to better define a context and mechanism for oncogenic 4EBP1. RESULTS Using a genome-scale shRNA screen on the SUM panel of breast cancer cell lines, we found 4EBP1 to be a strong hit in the 8p11 amplified SUM-44 cells, which have amplification and overexpression of 4EBP1. We then found that knock-down of 4EBP1 resulted in dramatic reductions in cell proliferation in 8p11 amplified breast cancer cells as well as in other luminal breast cancer cell lines, but had little or no effect on the proliferation of immortalized but non-tumorigenic human mammary epithelial cells. Kaplan-Meier analysis of EIF4EBP1 expression in breast cancer patients demonstrated that overexpression of this gene was associated with reduced relapse free patient survival across all breast tumor subtypes. CONCLUSIONS These results are consistent with an oncogenic role of 4EBP1 in luminal breast cancer and suggests a role for this protein in cell proliferation distinct from its more well-known role as a regulator of cap-dependent translation.
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Affiliation(s)
- Alexandria C. Rutkovsky
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, 171 Ashley Avenue, MSC 908, Charleston, SC 29425 USA
- Hollings Cancer Center, Medical University of South Carolina, 86 Jonathan Lucas Street, Charleston, SC 29425 USA
| | - Elizabeth S. Yeh
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, 173 Ashley Avenue, BSB 358, MSC 509, Charleston, SC 29425 USA
- Hollings Cancer Center, Medical University of South Carolina, 86 Jonathan Lucas Street, Charleston, SC 29425 USA
| | - Stephen T. Guest
- Department of Computational Medicine and Bioinformatics, University of Michigan, 500 S. State Street, Ann Arbor, MI 48109 USA
| | - Victoria J. Findlay
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, 171 Ashley Avenue, MSC 908, Charleston, SC 29425 USA
| | - Robin C. Muise-Helmericks
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, 173 Ashley Avenue, BSB 601, MSC 508, Charleston, SC 29425 USA
| | - Kent Armeson
- Hollings Cancer Center, Medical University of South Carolina, 86 Jonathan Lucas Street, Charleston, SC 29425 USA
- Department of Public Health Sciences, Medical University of South Carolina, 135 Cannon Street Suite 303 MSC 835, Charleston, USA
| | - Stephen P. Ethier
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, 171 Ashley Avenue, MSC 908, Charleston, SC 29425 USA
- Hollings Cancer Center, Medical University of South Carolina, 86 Jonathan Lucas Street, Charleston, SC 29425 USA
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22
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Miettinen TP, Kang JH, Yang LF, Manalis SR. Mammalian cell growth dynamics in mitosis. eLife 2019; 8:44700. [PMID: 31063131 PMCID: PMC6534395 DOI: 10.7554/elife.44700] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2018] [Accepted: 05/05/2019] [Indexed: 12/20/2022] Open
Abstract
The extent and dynamics of animal cell biomass accumulation during mitosis are unknown, primarily because growth has not been quantified with sufficient precision and temporal resolution. Using the suspended microchannel resonator and protein synthesis assays, we quantify mass accumulation and translation rates between mitotic stages on a single-cell level. For various animal cell types, growth rates in prophase are commensurate with or higher than interphase growth rates. Growth is only stopped as cells approach metaphase-to-anaphase transition and growth resumes in late cytokinesis. Mitotic arrests stop growth independently of arresting mechanism. For mouse lymphoblast cells, growth in prophase is promoted by CDK1 through increased phosphorylation of 4E-BP1 and cap-dependent protein synthesis. Inhibition of CDK1-driven mitotic translation reduces daughter cell growth. Overall, our measurements counter the traditional dogma that growth during mitosis is negligible and provide insight into antimitotic cancer chemotherapies.
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Affiliation(s)
- Teemu P Miettinen
- MRC Laboratory for Molecular Cell Biology, University College London, London, United Kingdom.,Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, United States
| | - Joon Ho Kang
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, United States.,Department of Physics, Massachusetts Institute of Technology, Cambridge, United States
| | - Lucy F Yang
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, United States
| | - Scott R Manalis
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, United States.,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, United States.,Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, United States
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23
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Choi SH, Martinez TF, Kim S, Donaldson C, Shokhirev MN, Saghatelian A, Jones KA. CDK12 phosphorylates 4E-BP1 to enable mTORC1-dependent translation and mitotic genome stability. Genes Dev 2019; 33:418-435. [PMID: 30819820 PMCID: PMC6446539 DOI: 10.1101/gad.322339.118] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Accepted: 01/22/2019] [Indexed: 01/23/2023]
Abstract
Here, Choi et al. show that CDK12, the RNA polymerase II C-terminal domain kinase, which regulates genome stability, expression of DNA repair genes, and cancer cell drug resistance, also phosphorylates the mRNA 5′ cap-binding repressor 4E-BP1 to promote translation of mTORC1-dependent mRNAs. Using RIP-seq and Ribo-seq, the authors found that CDK12 regulates binding of eIF4G to many mTORC1 target mRNAs, and identified specific CDK12 “translation-only” target mRNAs. The RNA polymerase II (RNAPII) C-terminal domain kinase, CDK12, regulates genome stability, expression of DNA repair genes, and cancer cell resistance to chemotherapy and immunotherapy. In addition to its role in mRNA biosynthesis of DNA repair genes, we show here that CDK12 phosphorylates the mRNA 5′ cap-binding repressor, 4E-BP1, to promote translation of mTORC1-dependent mRNAs. In particular, we found that phosphorylation of 4E-BP1 by mTORC1 (T37 and T46) facilitates subsequent CDK12 phosphorylation at two Ser–Pro sites (S65 and T70) that control the exchange of 4E-BP1 with eIF4G at the 5′ cap of CHK1 and other target mRNAs. RNA immunoprecipitation coupled with deep sequencing (RIP-seq) revealed that CDK12 regulates release of 4E-BP1, and binding of eIF4G, to many mTORC1 target mRNAs, including those needed for MYC transformation. Genome-wide ribosome profiling (Ribo-seq) further identified specific CDK12 “translation-only” target mRNAs, including many mTORC1 target mRNAs as well as many subunits of mitotic and centromere/centrosome complexes. Accordingly, confocal imaging analyses revealed severe chromosome misalignment, bridging, and segregation defects in cells deprived of CDK12 or CCNK. We conclude that the nuclear RNAPII-CTD kinase CDK12 cooperates with mTORC1, and controls a specialized translation network that is essential for mitotic chromosome stability.
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Affiliation(s)
- Seung H Choi
- Regulatory Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, California 92037, USA
| | - Thomas F Martinez
- Clayton Foundation Laboratory for Peptide Biology, The Salk Institute for Biological Studies, La Jolla, California 92037, USA
| | - Seongjae Kim
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, La Jolla, California 92037, USA
| | - Cynthia Donaldson
- Clayton Foundation Laboratory for Peptide Biology, The Salk Institute for Biological Studies, La Jolla, California 92037, USA
| | - Maxim N Shokhirev
- Razavi Newman Integrative Genomics and Bioinformatics Core, The Salk Institute for Biological Studies, La Jolla, California 92037, USA
| | - Alan Saghatelian
- Clayton Foundation Laboratory for Peptide Biology, The Salk Institute for Biological Studies, La Jolla, California 92037, USA
| | - Katherine A Jones
- Regulatory Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, California 92037, USA
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24
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Xia J, Luo Q, Huang S, Jiang F, Wang L, Wang G, Xie J, Liu J, Xu Y. Alisol B 23-acetate-induced HepG2 hepatoma cell death through mTOR signaling-initiated G 1 cell cycle arrest and apoptosis: A quantitative proteomic study. Chin J Cancer Res 2019; 31:375-388. [PMID: 31156308 PMCID: PMC6513739 DOI: 10.21147/j.issn.1000-9604.2019.02.12] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Objective The present study aimed to investigate the molecular events in alisol B 23-acetate (ABA) cytotoxic activity against a liver cancer cell line. Methods First, we employed a quantitative proteomics approach based on stable isotope labeling by amino acids in cell culture (SILAC) to identify the different proteins expressed in HepG2 liver cancer cells upon exposure to ABA. Next, bioinformatics analyses through DAVID and STRING on-line tools were used to predict the pathways involved. Finally, we applied functional validation including cell cycle analysis and Western blotting for apoptosis and mTOR pathway-related proteins to confirm the bioinformatics predictions. Results We identified 330 different proteins with the SILAC-based quantitative proteomics approach. The bioinformatics analysis and the functional validation revealed that the mTOR pathway, ribosome biogenesis, cell cycle, and apoptosis pathways were differentially regulated by ABA. G1 cell cycle arrest, apoptosis and mTOR inhibition were confirmed. Conclusions ABA, a potential mTOR inhibitor, induces the disruption of ribosomal biogenesis. It also affects the mTOR-MRP axis to cause G1 cell cycle arrest and finally leads to cancer cell apoptosis.
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Affiliation(s)
- Ji Xia
- School of Pharmaceutical Sciences, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Xiamen 361101, China
| | - Qiang Luo
- School of Pharmaceutical Sciences, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Xiamen 361101, China
| | - Shengbin Huang
- School of Pharmaceutical Sciences, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Xiamen 361101, China
| | - Fuquan Jiang
- School of Pharmaceutical Sciences, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Xiamen 361101, China
| | - Lin Wang
- Department of Oncology, Zhongshan Hospital of Xiamen University, Xiamen 361004, China.,Institute of Gastrointestinal Oncology, Medical College of Xiamen University, Xiamen 361101, China
| | - Guanghui Wang
- School of Pharmaceutical Sciences, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Xiamen 361101, China
| | - Jingjing Xie
- School of Pharmaceutical Sciences, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Xiamen 361101, China
| | - Jie Liu
- School of Pharmaceutical Sciences, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Xiamen 361101, China
| | - Yang Xu
- School of Pharmaceutical Sciences, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Xiamen 361101, China
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25
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Jansova D, Tetkova A, Koncicka M, Kubelka M, Susor A. Localization of RNA and translation in the mammalian oocyte and embryo. PLoS One 2018. [PMID: 29529035 PMCID: PMC5846722 DOI: 10.1371/journal.pone.0192544] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The tight correlation between mRNA distribution and subsequent protein localization and function indicate a major role for mRNA localization within the cell. RNA localization, followed by local translation, presents a mechanism for spatial and temporal gene expression regulation utilized by various cell types. However, little is known about mRNA localization and translation in the mammalian oocyte and early embryo. Importantly, fully-grown oocyte becomes transcriptionally inactive and only utilizes transcripts previously synthesized and stored during earlier development. We discovered an abundant RNA population in the oocyte and early embryo nucleus together with RNA binding proteins. We also characterized specific ribosomal proteins, which contribute to translation in the oocyte and embryo. By applying selected markers to mouse and human oocytes, we found that there might be a similar mechanism of RNA metabolism in both species. In conclusion, we visualized the localization of RNAs and translation machinery in the oocyte, that could shed light on this terra incognita of these unique cell types in mouse and human.
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Affiliation(s)
- Denisa Jansova
- Institute of Animal Physiology and Genetics, CAS, Libechov, Czech Republic
- Department of Cell Biology, Faculty of Science, Charles University in Prague, Prague 2, Czech Republic
- * E-mail: (DJ); (AS)
| | - Anna Tetkova
- Institute of Animal Physiology and Genetics, CAS, Libechov, Czech Republic
- Department of Cell Biology, Faculty of Science, Charles University in Prague, Prague 2, Czech Republic
| | - Marketa Koncicka
- Institute of Animal Physiology and Genetics, CAS, Libechov, Czech Republic
- Department of Cell Biology, Faculty of Science, Charles University in Prague, Prague 2, Czech Republic
| | - Michal Kubelka
- Institute of Animal Physiology and Genetics, CAS, Libechov, Czech Republic
| | - Andrej Susor
- Institute of Animal Physiology and Genetics, CAS, Libechov, Czech Republic
- * E-mail: (DJ); (AS)
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Kalous J, Tetkova A, Kubelka M, Susor A. Importance of ERK1/2 in Regulation of Protein Translation during Oocyte Meiosis. Int J Mol Sci 2018; 19:ijms19030698. [PMID: 29494492 PMCID: PMC5877559 DOI: 10.3390/ijms19030698] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 02/23/2018] [Accepted: 02/26/2018] [Indexed: 02/07/2023] Open
Abstract
Although the involvement of the extracellular signal-regulated kinases 1 and 2 (ERK1/2) pathway in the regulation of cytostatic factor (CSF) activity; as well as in microtubules organization during meiotic maturation of oocytes; has already been described in detail; rather less attention has been paid to the role of ERK1/2 in the regulation of mRNA translation. However; important data on the role of ERK1/2 in translation during oocyte meiosis have been documented. This review focuses on recent findings regarding the regulation of translation and the role of ERK1/2 in this process in the meiotic cycle of mammalian oocytes. The specific role of ERK1/2 in the regulation of mammalian target of rapamycin (mTOR); eukaryotic translation initiation factor 4E (eIF4E) and cytoplasmic polyadenylation element binding protein 1 (CPEB1) activity is addressed along with additional focus on the other key players involved in protein translation.
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Affiliation(s)
- Jaroslav Kalous
- Institute of Animal Physiology and Genetics, Academy of Sciences of the Czech Republic, Rumburska 89, 27721 Libechov, Czech Republic.
| | - Anna Tetkova
- Institute of Animal Physiology and Genetics, Academy of Sciences of the Czech Republic, Rumburska 89, 27721 Libechov, Czech Republic.
- Department of Cell Biology, Faculty of Science, Charles University in Prague, Albertov 6, 12843 Prague 2, Czech Republic.
| | - Michal Kubelka
- Institute of Animal Physiology and Genetics, Academy of Sciences of the Czech Republic, Rumburska 89, 27721 Libechov, Czech Republic.
| | - Andrej Susor
- Institute of Animal Physiology and Genetics, Academy of Sciences of the Czech Republic, Rumburska 89, 27721 Libechov, Czech Republic.
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Moundoyi H, Demouy J, Le Panse S, Morales J, Sarels B, Cormier P. Toward Multiscale Modeling of Molecular and Biochemical Events Occurring at Fertilization Time in Sea Urchins. Results Probl Cell Differ 2018; 65:69-89. [DOI: 10.1007/978-3-319-92486-1_5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023]
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28
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Severance AL, Latham KE. PLK1 regulates spindle association of phosphorylated eukaryotic translation initiation factor 4E-binding protein and spindle function in mouse oocytes. Am J Physiol Cell Physiol 2017; 313:C501-C515. [PMID: 28794108 PMCID: PMC5792166 DOI: 10.1152/ajpcell.00075.2017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 08/03/2017] [Accepted: 08/04/2017] [Indexed: 11/22/2022]
Abstract
Oocyte meiotic spindles are associated with spindle-enriched mRNAs, phosphorylated ribosome protein S6, and phosphorylated variants of the key translational regulator, eukaryotic translation initiation factor 4E-binding protein 1 (eIF4E-BP1), consistent with translational control of localized mRNAs by eIF4E-BP1 in facilitating spindle formation and stability. Using specific kinase inhibitors, we determined which kinases regulate phosphorylation status of eIF4E-BP1 associated with meiotic spindles in mouse oocytes and effects of kinase inhibition on chromosome congression and spindle formation. Neither ataxia telangiectasia-mutated kinase nor mechanistic target of rapamycin inhibition significantly affected phosphorylation status of spindle-associated eIF4E-BP1 at the phosphorylation sites examined. Spindle-associated phospho-eIF4E-BP1, spindle formation, and chromosome congression were strongly disrupted by polo-like kinase I (PLK1) inhibition at both metaphase I (MI) and MII. In addition, direct inhibition of eIF4E-BP1 via 4EGI led to spindle defects at MI, indicating a direct role for eIF4E-BP1 phosphorylation in meiotic spindle formation. PLK1 also regulated microtubule dynamics throughout the ooplasm, indicating likely coordination between spindle dynamics and broader ooplasm cytoskeletal dynamics. Because diverse upstream signaling pathways converge on PLK1, these results implicate PLK1 as a major regulatory nexus coupling endogenous and exogenous signals via eIF4E-BP1 to the regulation of spindle formation and stability.
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Affiliation(s)
- Ashley L Severance
- Reproductive and Developmental Sciences Program, Michigan State University , East Lansing, Michigan
- Genetics Graduate Program, Michigan State University , East Lansing, Michigan
| | - Keith E Latham
- Reproductive and Developmental Sciences Program, Michigan State University , East Lansing, Michigan
- Genetics Graduate Program, Michigan State University , East Lansing, Michigan
- Department of Animal Science, Michigan State University , East Lansing, Michigan ; and
- Department of Obstetrics, Gynecology, and Reproductive Biology, Michigan State University , East Lansing, Michigan
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Jansova D, Koncicka M, Tetkova A, Cerna R, Malik R, del Llano E, Kubelka M, Susor A. Regulation of 4E-BP1 activity in the mammalian oocyte. Cell Cycle 2017; 16:927-939. [PMID: 28272965 PMCID: PMC5462087 DOI: 10.1080/15384101.2017.1295178] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Revised: 01/31/2017] [Accepted: 02/08/2017] [Indexed: 01/03/2023] Open
Abstract
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.
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Affiliation(s)
- Denisa Jansova
- Institute of Animal Physiology and Genetics, ASC, Libechov, Czech Republic
| | - Marketa Koncicka
- Institute of Animal Physiology and Genetics, ASC, Libechov, Czech Republic
| | - Anna Tetkova
- Institute of Animal Physiology and Genetics, ASC, Libechov, Czech Republic
| | - Renata Cerna
- Institute of Animal Physiology and Genetics, ASC, Libechov, Czech Republic
| | - Radek Malik
- Institute of Molecular Genetics, ASCR, Prague, Czech Republic
| | - Edgar del Llano
- Institute of Animal Physiology and Genetics, ASC, Libechov, Czech Republic
| | - Michal Kubelka
- Institute of Animal Physiology and Genetics, ASC, Libechov, Czech Republic
| | - Andrej Susor
- Institute of Animal Physiology and Genetics, ASC, Libechov, Czech Republic
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Affiliation(s)
- Patrick Cormier
- a Sorbonne Universités, UPMC Univ Paris 06, UMR 8227, Integrative Biology of Marine Models, Translation Cell Cycle and Development, Station Biologique de Roscoff , Roscoff cedex , France.,b CNRS, UMR 8227, Integrative Biology of Marine Models, Station Biologique de Roscoff , Roscoff cedex , France
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31
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Abstract
Fully grown oocytes arrest meiosis at prophase I and deposit maternal RNAs. A subset of maternal transcripts is stored in a dormant state in the oocyte, and the timely driven translation of specific mRNAs guides meiotic progression, the oocyte-embryo transition, and early embryo development. 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 at the level of protein synthesis.This chapter focuses on the recent findings on RNA distribution related to the temporal and spatial translational control of the meiotic cycle progression in mammalian oocytes. We discuss the most relevant mechanisms involved in the organization of the oocyte's maternal transcriptome storage and localization, and the regulation of translation, in correlation with the regulation of oocyte meiotic progression.
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