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Singh R, Purohit R. Computational analysis of protein-ligand interaction by targeting a cell cycle restrainer. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2023; 231:107367. [PMID: 36716649 DOI: 10.1016/j.cmpb.2023.107367] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Revised: 01/10/2023] [Accepted: 01/22/2023] [Indexed: 06/18/2023]
Abstract
BACKGROUND AND OBJECTIVE The cyclin-dependent kinases 4/6 (CDK4/6) are among the most crucial controllers of the cell cycle, and their abnormal activity may induce uncontrolled cell multiplication, leading to cancers. The FDA currently approved three CDK4/6 inhibitors, however, they are associated with a variety of side effects. Thus it is required to design/develop novel potent and safe CDK4/6 inhibitors. METHODS In the present work, we furnished an integrated in-silico approach followed by steered molecular dynamics (SMD) simulations to identify molecules that can be developed into novel CDK4/6 inhibitors. RESULTS Out of thirty-two 3-methyleneisoindolin-1-one molecules we selected top three M18, M24, and M32 molecules as potential drug candidates based on their respective interaction energies. According to the robust 250 ns MD simulations and thermodynamic free energy, M24 was the best molecule in comparison to palbociclib. In SMD, M24 required ∼205.587 kJ/mol/nm external pulling force, while palbociclib needed ∼160.97 kJ/mol/nm to dissociate from the binding pocket of the CDK4. CONCLUSIONS The high pulling force required for M24 dissociation from the binding site denotes stronger binding with CDK4. Therefore, M24 offers the possibility of a critical starting structure in developing effective CDK4 inhibitors.
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Affiliation(s)
- Rahul Singh
- Structural Bioinformatics Lab, CSIR-Institute of Himalayan Bioresource Technology (CSIR-IHBT), Palampur, HP 176061, India; Biotechnology Division, CSIR-IHBT, Palampur, HP 176061, India; Academy of Scientific & Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Rituraj Purohit
- Structural Bioinformatics Lab, CSIR-Institute of Himalayan Bioresource Technology (CSIR-IHBT), Palampur, HP 176061, India; Biotechnology Division, CSIR-IHBT, Palampur, HP 176061, India; Academy of Scientific & Innovative Research (AcSIR), Ghaziabad 201002, India.
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2
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eIF4B mRNA Translation Contributes to Cleavage Dynamics in Early Sea Urchin Embryos. BIOLOGY 2022; 11:biology11101408. [PMID: 36290313 PMCID: PMC9598784 DOI: 10.3390/biology11101408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 09/14/2022] [Accepted: 09/20/2022] [Indexed: 11/17/2022]
Abstract
Simple Summary Cell division, also known as mitosis, relies on a complex cascade of molecular events that orchestrates the whole process and decides when cells can start dividing. A key factor in this process is protein synthesis, which is carefully regulated inside the cell to assure the timely production of all the proteins required for mitosis. The embryos of sea urchins divide rapidly after fertilization and represent an informative model to analyze the role of protein synthesis regulation during cell cycle progression. For example, the analysis in the 1980s of sea urchin embryos fostered the discovery of Cyclin B, the first representative of a family of proteins that plays a universal role in controlling cell division. This finding was awarded in 2001 with the Nobel Prize in Physiology and Medicine. However, much remains to be learned, and how protein synthesis controls the time and speed of mitosis in a developing embryo is still unclear. For instance, discovering whether the translation of other mRNAs than mitotic cyclins is required to finely regulate the rate of embryonic cleavage has never been tested. In this work, we investigated the role of the translation of an mRNA encoding a protein called eIF4B in the dynamics of embryonic cell division. We showed that newly synthesized eIF4B directly impacts cell division rates in two sea urchin species. Cell divisions are delayed when the production of eIF4B is inhibited in a fertilized egg. Conversely, increased production of eIF4B accelerates mitosis. Therefore, eIF4B mRNA translation represents a new means to regulate the pace of embryonic cleavages. Moreover, since eIF4B is a translational regulator, our findings suggest that the function of its mRNA translation is boosting the production of other proteins essential for mitosis. The cells of the sea urchin embryos seem thus equipped with a controlling device capable of modulating cell division rates, a molecular switch that could contribute to coordinating the first steps of development in other animals as well. Abstract During the first steps of sea urchin development, fertilization elicits a marked increase in protein synthesis essential for subsequent cell divisions. While the translation of mitotic cyclin mRNAs is crucial, we hypothesized that additional mRNAs must be translated to finely regulate the onset into mitosis. One of the maternal mRNAs recruited onto active polysomes at this stage codes for the initiation factor eIF4B. Here, we show that the sea urchin eIF4B orthologs present the four specific domains essential for eIF4B function and that Paracentrotus lividus eIF4B copurifies with eIF4E in a heterologous system. In addition, we investigated the role of eIF4B mRNA de novo translation during the two first embryonic divisions of two species, P. lividus and Sphaerechinus granularis. Our results show that injection of a morpholino directed against eIF4B mRNA results in a downregulation of translational activity and delays cell division in these two echinoids. Conversely, injection of an mRNA encoding for P. lividus eIF4B stimulates translation and significantly accelerates cleavage rates. Taken together, our findings suggest that eIF4B mRNA de novo translation participates in a conserved regulatory loop that contributes to orchestrating protein synthesis and modulates cell division rhythm during early sea urchin development.
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3
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Cacioppo R, Lindon C. Regulating the regulator: a survey of mechanisms from transcription to translation controlling expression of mammalian cell cycle kinase Aurora A. Open Biol 2022; 12:220134. [PMID: 36067794 PMCID: PMC9448500 DOI: 10.1098/rsob.220134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Aurora Kinase A (AURKA) is a positive regulator of mitosis with a strict cell cycle-dependent expression pattern. Recently, novel oncogenic roles of AURKA have been uncovered that are independent of the kinase activity and act within multiple signalling pathways, including cell proliferation, survival and cancer stem cell phenotypes. For this, cellular abundance of AURKA protein is per se crucial and must be tightly fine-tuned. Indeed, AURKA is found overexpressed in different cancers, typically as a result of gene amplification or enhanced transcription. It has however become clear that impaired processing, decay and translation of AURKA mRNA can also offer the basis for altered AURKA levels. Accordingly, the involvement of gene expression mechanisms controlling AURKA expression in human diseases is increasingly recognized and calls for much more research. Here, we explore and create an integrated view of the molecular processes regulating AURKA expression at the level of transcription, post-transcription and translation, intercalating discussion on how impaired regulation underlies disease. Given that targeting AURKA levels might affect more functions compared to inhibiting the kinase activity, deeper understanding of its gene expression may aid the design of alternative and therapeutically more successful ways of suppressing the AURKA oncogene.
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Affiliation(s)
- Roberta Cacioppo
- Department of Pharmacology, University of Cambridge, Cambridge CB2 1PD, UK
| | - Catherine Lindon
- Department of Pharmacology, University of Cambridge, Cambridge CB2 1PD, UK
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4
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Luperchio AM, Jónsson SR, Salamango DJ. Evolutionary Conservation of PP2A Antagonism and G2/M Cell Cycle Arrest in Maedi-Visna Virus Vif. Viruses 2022; 14:1701. [PMID: 36016323 PMCID: PMC9413702 DOI: 10.3390/v14081701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 07/29/2022] [Accepted: 07/29/2022] [Indexed: 11/18/2022] Open
Abstract
The canonical function of lentiviral Vif proteins is to counteract the mutagenic potential of APOBEC3 antiviral restriction factors. However, recent studies have discovered that Vif proteins from diverse HIV-1 and simian immunodeficiency virus (SIV) isolates degrade cellular B56 phosphoregulators to remodel the host phosphoproteome and induce G2/M cell cycle arrest. Here, we evaluate the conservation of this activity among non-primate lentiviral Vif proteins using fluorescence-based degradation assays and demonstrate that maedi-visna virus (MVV) Vif efficiently degrades all five B56 family members. Testing an extensive panel of single amino acid substitution mutants revealed that MVV Vif recognizes B56 proteins through a conserved network of electrostatic interactions. Furthermore, experiments using genetic and pharmacologic approaches demonstrate that degradation of B56 proteins requires the cellular cofactor cyclophilin A. Lastly, MVV Vif-mediated depletion of B56 proteins induces a potent G2/M cell cycle arrest phenotype. Therefore, remodeling of the cellular phosphoproteome and induction of G2/M cell cycle arrest are ancient and conserved functions of lentiviral Vif proteins, which suggests that they are advantageous for lentiviral pathogenesis.
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Affiliation(s)
- Adeline M. Luperchio
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, New York, NY 11794, USA;
| | - Stefán R. Jónsson
- Institute for Experimental Pathology, University of Iceland, Keldur, 112 Reykjavik, Iceland;
| | - Daniel J. Salamango
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, New York, NY 11794, USA;
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5
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Li X, Zhu M, Zang M, Cao D, Xie Z, Liang H, Bian Z, Zhao T, Hu Z, Xu EY. PUMILIO-mediated translational control of somatic cell cycle program promotes folliculogenesis and contributes to ovarian cancer progression. Cell Mol Life Sci 2022; 79:279. [PMID: 35507203 PMCID: PMC11072887 DOI: 10.1007/s00018-022-04254-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 03/14/2022] [Accepted: 03/16/2022] [Indexed: 02/06/2023]
Abstract
Translational control is a fundamental mechanism regulating animal germ cell development. Gonadal somatic cells provide support and microenvironment for germ cell development to ensure fertility, yet the roles of translational control in gonadal somatic compartment remain largely undefined. We found that mouse homolog of conserved fly germline stem cell factor Pumilio, PUM1, is absent in oocytes of all growing follicles after the primordial follicle stage, instead, it is highly expressed in somatic compartments of ovaries. Global loss of Pum1, not oocyte-specific loss of Pum1, led to a significant reduction in follicular number and size as well as fertility. Whole-genome identification of PUM1 targets in ovarian somatic cells revealed an enrichment of cell proliferation pathway, including 48 key regulators of cell phase transition. Consistently granulosa cells proliferation is reduced and the protein expression of the PUM-bound Cell Cycle Regulators (PCCR) were altered accordingly in mutant ovaries, and specifically in granulosa cells. Increase in negative regulator expression and decrease in positive regulators in the mutant ovaries support a coordinated translational control of somatic cell cycle program via PUM proteins. Furthermore, postnatal knockdown, but not postnatal oocyte-specific loss, of Pum1 in Pum2 knockout mice reduced follicular growth and led to similar expression alteration of PCCR genes, supporting a critical role of PUM-mediated translational control in ovarian somatic cells for mammalian female fertility. Finally, expression of human PUM protein and its regulated cell cycle targets exhibited significant correlation with ovarian cancer and prognosis for cancer survival. Hence, PUMILIO-mediated cell cycle regulation represents an important mechanism in mammalian female reproduction and human cancer biology.
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Affiliation(s)
- Xin Li
- State Key Laboratory of Reproductive Medicine (Suzhou Centre), The Affiliated Suzhou Hospital of Nanjing Medical University, Suzhou Municipal Hospital, Gusu School, Nanjing Medical University, Suzhou, Jiangsu, China
| | - Mengyi Zhu
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, 211166, China
| | - Min Zang
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, 211166, China
| | - Dandan Cao
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, 211166, China
| | - Zhengyao Xie
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, 211166, China
| | - Haibo Liang
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, 211166, China
| | - Zexin Bian
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, 211166, China
| | - Tingting Zhao
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, 211166, China
| | - Zhibin Hu
- State Key Laboratory of Reproductive Medicine (Suzhou Centre), The Affiliated Suzhou Hospital of Nanjing Medical University, Suzhou Municipal Hospital, Gusu School, Nanjing Medical University, Suzhou, Jiangsu, China
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, 211166, China
| | - Eugene Yujun Xu
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, 211166, China.
- Department of Neurology, Center for Reproductive Science, Feinberg School of Medicine, Northwestern University Feinberg School of Medicine, Chicago, USA.
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6
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Ambaru B, Gangadharan GM, Subramanya HS, Gupta CM. Profilin is involved in G1 to S phase progression and mitotic spindle orientation during Leishmania donovani cell division cycle. PLoS One 2022; 17:e0265692. [PMID: 35316283 PMCID: PMC8939790 DOI: 10.1371/journal.pone.0265692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 03/04/2022] [Indexed: 11/27/2022] Open
Abstract
Profilin is a multi-ligand binding protein, which is a key regulator of actin dynamics and involved in regulating several cellular functions. It is present in all eukaryotes, including trypanosomatids such as Leishmania. However, not much is known about its functions in these organisms. Our earlier studies have shown that Leishmania parasites express a single homologue of profilin (LdPfn) that binds actin, phosphoinositides and poly- L- proline motives, and depletion of its intracellular pool to 50%of normal levels affects the cell growth and intracellular trafficking. Here, we show, employing affinity pull-down and mass spectroscopy, that LdPfn interacted with a large number of proteins, including those involved in mRNA processing and protein translation initiation, such as eIF4A1. Further, we reveal, using mRNA Seq analysis, that depletion of LdPfn in Leishmania cells (LdPfn+/-) resulted in significantly reduced expression of genes which encode proteins involved in cell cycle regulation, mRNA translation initiation, nucleosides and amino acids transport. In addition, we show that in LdPfn+/- cells, cellular levels of eIF4A1 protein were significantly decreased, and during their cell division cycle, G1-to-S phase progression was delayed and orientation of mitotic spindle altered. These changes were, however, reversed to normal by episomal expression of GFP-LdPfn in LdPfn+/- cells. Taken together, our results indicate that profilin is involved in regulation of G1-to-S phase progression and mitotic spindle orientation in Leishmania cell cycle, perhaps through its interaction with elF4A1 protein.
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Affiliation(s)
- Bindu Ambaru
- Institute of Bioinformatics and Applied Biotechnology, Bengaluru, Karnataka, India
- Manipal Academy of Higher Education, Manipal, Karnataka, India
| | | | | | - Chhitar M. Gupta
- Institute of Bioinformatics and Applied Biotechnology, Bengaluru, Karnataka, India
- * E-mail:
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7
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Clemm von Hohenberg K, Müller S, Schleich S, Meister M, Bohlen J, Hofmann TG, Teleman AA. Cyclin B/CDK1 and Cyclin A/CDK2 phosphorylate DENR to promote mitotic protein translation and faithful cell division. Nat Commun 2022; 13:668. [PMID: 35115540 PMCID: PMC8813921 DOI: 10.1038/s41467-022-28265-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 01/12/2022] [Indexed: 12/11/2022] Open
Abstract
DENR and MCTS1 have been identified as oncogenes in several different tumor entities. The heterodimeric DENR·MCTS1 protein complex promotes translation of mRNAs containing upstream Open Reading Frames (uORFs). We show here that DENR is phosphorylated on Serine 73 by Cyclin B/CDK1 and Cyclin A/CDK2 at the onset of mitosis, and then dephosphorylated as cells exit mitosis. Phosphorylation of Ser73 promotes mitotic stability of DENR protein and prevents its cleavage at Asp26. This leads to enhanced translation of mRNAs involved in mitosis. Indeed, we find that roughly 40% of all mRNAs with elevated translation in mitosis are DENR targets. In the absence of DENR or of Ser73 phosphorylation, cells display elevated levels of aberrant mitoses and cell death. This provides a mechanism how the cell cycle regulates translation of a subset of mitotically relevant mRNAs during mitosis. The cell cycle regulates translation during mitosis by controlling DENR stability. Here, the authors show the non-canonical translation initiation complex DENR·MCTS1 is phosphorylated during mitosis by CDK1 and 2, enabling the translation of genes needed for proper mitotic progression.
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Affiliation(s)
- Katharina Clemm von Hohenberg
- German Cancer Research Center (DKFZ), 69120, Heidelberg, Germany.,Heidelberg University, 69120, Heidelberg, Germany.,CellNetworks-Cluster of Excellence, Heidelberg University, Heidelberg, Germany.,Department of Medicine III, Universitätsmedizin Mannheim, 68167, Mannheim, Germany
| | - Sandra Müller
- German Cancer Research Center (DKFZ), 69120, Heidelberg, Germany.,Heidelberg University, 69120, Heidelberg, Germany
| | - Sibylle Schleich
- German Cancer Research Center (DKFZ), 69120, Heidelberg, Germany.,Heidelberg University, 69120, Heidelberg, Germany
| | - Matthias Meister
- Division of Viral Transformation Mechanisms, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Jonathan Bohlen
- German Cancer Research Center (DKFZ), 69120, Heidelberg, Germany.,Heidelberg University, 69120, Heidelberg, Germany.,CellNetworks-Cluster of Excellence, Heidelberg University, Heidelberg, Germany.,Laboratory of Human Genetics of Infectious Diseases, Necker Branch, INSERM U1163, Paris, France.,University of Paris, Imagine Institute, Paris, France
| | - Thomas G Hofmann
- Institute of Toxicology, University Medical Center Mainz at the Johannes Gutenberg University of Mainz, Mainz, Germany
| | - Aurelio A Teleman
- German Cancer Research Center (DKFZ), 69120, Heidelberg, Germany. .,Heidelberg University, 69120, Heidelberg, Germany. .,CellNetworks-Cluster of Excellence, Heidelberg University, Heidelberg, Germany.
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8
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Krenning L, Sonneveld S, Tanenbaum M. Time-resolved single-cell sequencing identifies multiple waves of mRNA decay during the mitosis-to-G1 phase transition. eLife 2022; 11:71356. [PMID: 35103592 PMCID: PMC8806192 DOI: 10.7554/elife.71356] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 01/17/2022] [Indexed: 01/20/2023] Open
Abstract
Accurate control of the cell cycle is critical for development and tissue homeostasis, and requires precisely timed expression of many genes. Cell cycle gene expression is regulated through transcriptional and translational control, as well as through regulated protein degradation. Here, we show that widespread and temporally controlled mRNA decay acts as an additional mechanism for gene expression regulation during the cell cycle in human cells. We find that two waves of mRNA decay occur sequentially during the mitosis-to-G1 phase transition, and we identify the deadenylase CNOT1 as a factor that contributes to mRNA decay during this cell cycle transition. Collectively, our data show that, akin to protein degradation, scheduled mRNA decay helps to reshape cell cycle gene expression as cells move from mitosis into G1 phase.
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Affiliation(s)
- Lenno Krenning
- Oncode Institute, Hubrecht Institute – KNAW and University Medical Center UtrechtUtrechtNetherlands
| | - Stijn Sonneveld
- Oncode Institute, Hubrecht Institute – KNAW and University Medical Center UtrechtUtrechtNetherlands
| | - Marvin Tanenbaum
- Oncode Institute, Hubrecht Institute – KNAW and University Medical Center UtrechtUtrechtNetherlands
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9
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Gilmutdinov R, Kozlov EN, Yakovlev KV, Olenina LV, Kotov AA, Barr J, Zhukova M, Schedl P, Shidlovskii YV. The 3'UTR of the Drosophila CPEB translation factor gene orb2 plays a crucial role in spermatogenesis. Development 2021; 148:272122. [PMID: 34473243 DOI: 10.1242/dev.198788] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Accepted: 07/22/2021] [Indexed: 01/27/2023]
Abstract
CPEB proteins are conserved translation regulators involved in multiple biological processes. One of these proteins in Drosophila, Orb2, is a principal player in spermatogenesis. It is required for meiosis and spermatid differentiation. During the later process, orb2 mRNA and protein are localized within the developing spermatid. To evaluate the role of the orb2 mRNA 3'UTR in spermatogenesis, we used the CRISPR/Cas9 system to generate a deletion of the orb2 3'UTR, orb2R. This deletion disrupts the process of spermatid differentiation but has no apparent effect on meiosis. Differentiation abnormalities include defects in the initial polarization of the 64-cell spermatid cysts, mislocalization of mRNAs and proteins in the elongating spermatid tails, altered morphology of the elongating spermatid tails, and defects in the assembly of the individualization complex. These disruptions in differentiation appear to arise because orb2 mRNA and protein are not properly localized within the 64-cell spermatid cyst.
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Affiliation(s)
- Rudolf Gilmutdinov
- Department of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, Moscow 119334, Russia
| | - Eugene N Kozlov
- Department of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, Moscow 119334, Russia
| | - Konstantin V Yakovlev
- Department of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, Moscow 119334, Russia.,Laboratory of Cytotechnology, A.V. Zhirmunsky National Scientific Center of Marine Biology, Far Eastern Branch of the Russian Academy of Sciences, Vladivostok 690041, Russia
| | - Ludmila V Olenina
- Department of Molecular Genetics of Cell, Institute of Molecular Genetics, National Research Centre Kurchatov Institute, Moscow 123182, Russia
| | - Alexei A Kotov
- Department of Molecular Genetics of Cell, Institute of Molecular Genetics, National Research Centre Kurchatov Institute, Moscow 123182, Russia
| | - Justinn Barr
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544-1014, USA
| | - Mariya Zhukova
- Department of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, Moscow 119334, Russia
| | - Paul Schedl
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544-1014, USA
| | - Yulii V Shidlovskii
- Department of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, Moscow 119334, Russia.,Department of Biology and General Genetics, I.M. Sechenov First Moscow State Medical University, Moscow 119048, Russia
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10
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Anger M, Radonova L, Horakova A, Sekach D, Charousova M. Impact of Global Transcriptional Silencing on Cell Cycle Regulation and Chromosome Segregation in Early Mammalian Embryos. Int J Mol Sci 2021; 22:9073. [PMID: 34445775 PMCID: PMC8396661 DOI: 10.3390/ijms22169073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 08/14/2021] [Accepted: 08/18/2021] [Indexed: 11/17/2022] Open
Abstract
The onset of an early development is, in mammals, characterized by profound changes of multiple aspects of cellular morphology and behavior. These are including, but not limited to, fertilization and the merging of parental genomes with a subsequent transition from the meiotic into the mitotic cycle, followed by global changes of chromatin epigenetic modifications, a gradual decrease in cell size and the initiation of gene expression from the newly formed embryonic genome. Some of these important, and sometimes also dramatic, changes are executed within the period during which the gene transcription is globally silenced or not progressed, and the regulation of most cellular activities, including those mentioned above, relies on controlled translation. It is known that the blastomeres within an early embryo are prone to chromosome segregation errors, which might, when affecting a significant proportion of a cell within the embryo, compromise its further development. In this review, we discuss how the absence of transcription affects the transition from the oocyte to the embryo and what impact global transcriptional silencing might have on the basic cell cycle and chromosome segregation controlling mechanisms.
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Affiliation(s)
- Martin Anger
- Central European Institute of Technology, Department of Genetics and Reproduction, Veterinary Research Institute, 621 00 Brno, Czech Republic; (L.R.); (A.H.); (D.S.); (M.C.)
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11
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Sergeeva O, Zatsepin T. RNA Helicases as Shadow Modulators of Cell Cycle Progression. Int J Mol Sci 2021; 22:2984. [PMID: 33804185 PMCID: PMC8001981 DOI: 10.3390/ijms22062984] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 03/06/2021] [Accepted: 03/10/2021] [Indexed: 02/07/2023] Open
Abstract
The progress of the cell cycle is directly regulated by modulation of cyclins and cyclin-dependent kinases. However, many proteins that control DNA replication, RNA transcription and the synthesis and degradation of proteins can manage the activity or levels of master cell cycle regulators. Among them, RNA helicases are key participants in RNA metabolism involved in the global or specific tuning of cell cycle regulators at the level of transcription and translation. Several RNA helicases have been recently evaluated as promising therapeutic targets, including eIF4A, DDX3 and DDX5. However, targeting RNA helicases can result in side effects due to the influence on the cell cycle. In this review, we discuss direct and indirect participation of RNA helicases in the regulation of the cell cycle in order to draw attention to downstream events that may occur after suppression or inhibition of RNA helicases.
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Affiliation(s)
- Olga Sergeeva
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30b1, 121205 Moscow, Russia;
| | - Timofei Zatsepin
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30b1, 121205 Moscow, Russia;
- Department of Chemistry, Lomonosov Moscow State University, 119992 Moscow, Russia
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12
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Salamango DJ, Harris RS. Demystifying Cell Cycle Arrest by HIV-1 Vif. Trends Microbiol 2021; 29:381-384. [PMID: 33478820 DOI: 10.1016/j.tim.2021.01.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 12/28/2020] [Accepted: 01/04/2021] [Indexed: 11/26/2022]
Abstract
Although APOBEC3 degradation is the canonical function of HIV-1 Vif, this viral protein also induces potent cell cycle arrest through a newly defined mechanism. Here, we review recent advances in this area and propose that the scope of this activity may go beyond subversion of the host cell cycle.
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Affiliation(s)
- Daniel J Salamango
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA; Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455, USA.
| | - Reuben S Harris
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA; Howard Hughes Medical Institute, University of Minnesota, Minneapolis, MN 55455, USA.
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13
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Salamango DJ, Harris RS. Dual Functionality of HIV-1 Vif in APOBEC3 Counteraction and Cell Cycle Arrest. Front Microbiol 2021; 11:622012. [PMID: 33510734 PMCID: PMC7835321 DOI: 10.3389/fmicb.2020.622012] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 12/11/2020] [Indexed: 01/02/2023] Open
Abstract
Accessory proteins are a key feature that distinguishes primate immunodeficiency viruses such as human immunodeficiency virus type I (HIV-1) from other retroviruses. A prime example is the virion infectivity factor, Vif, which hijacks a cellular co-transcription factor (CBF-β) to recruit a ubiquitin ligase complex (CRL5) to bind and degrade antiviral APOBEC3 enzymes including APOBEC3D (A3D), APOBEC3F (A3F), APOBEC3G (A3G), and APOBEC3H (A3H). Although APOBEC3 antagonism is essential for viral pathogenesis, and a more than sufficient functional justification for Vif’s evolution, most viral proteins have evolved multiple functions. Indeed, Vif has long been known to trigger cell cycle arrest and recent studies have shed light on the underlying molecular mechanism. Vif accomplishes this function using the same CBF-β/CRL5 ubiquitin ligase complex to degrade a family of PPP2R5 phospho-regulatory proteins. These advances have helped usher in a new era of accessory protein research and fresh opportunities for drug development.
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Affiliation(s)
- Daniel J Salamango
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, United States.,Masonic Cancer Center, University of Minnesota, Minneapolis, MN, United States.,Institute for Molecular Virology, University of Minnesota, Minneapolis, MN, United States
| | - Reuben S Harris
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, United States.,Masonic Cancer Center, University of Minnesota, Minneapolis, MN, United States.,Institute for Molecular Virology, University of Minnesota, Minneapolis, MN, United States.,Howard Hughes Medical Institute, University of Minnesota, Minneapolis, MN, United States
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14
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Laureau R, Dyatel A, Dursuk G, Brown S, Adeoye H, Yue JX, De Chiara M, Harris A, Ünal E, Liti G, Adams IR, Berchowitz LE. Meiotic Cells Counteract Programmed Retrotransposon Activation via RNA-Binding Translational Repressor Assemblies. Dev Cell 2020; 56:22-35.e7. [PMID: 33278343 DOI: 10.1016/j.devcel.2020.11.008] [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] [Received: 03/27/2020] [Revised: 06/25/2020] [Accepted: 11/06/2020] [Indexed: 12/14/2022]
Abstract
Retrotransposon proliferation poses a threat to germline integrity. While retrotransposons must be activated in developing germ cells in order to survive and propagate, how they are selectively activated in the context of meiosis is unclear. We demonstrate that the transcriptional activation of Ty3/Gypsy retrotransposons and host defense are controlled by master meiotic regulators. We show that budding yeast Ty3/Gypsy co-opts binding sites of the essential meiotic transcription factor Ndt80 upstream of the integration site, thereby tightly linking its transcriptional activation to meiotic progression. We also elucidate how yeast cells thwart Ty3/Gypsy proliferation by blocking translation of the retrotransposon mRNA using amyloid-like assemblies of the RNA-binding protein Rim4. In mammals, several inactive Ty3/Gypsy elements are undergoing domestication. We show that mammals utilize equivalent master meiotic regulators (Stra8, Mybl1, Dazl) to regulate Ty3/Gypsy-derived genes in developing gametes. Our findings inform how genes that are evolving from retrotransposons can build upon existing regulatory networks during domestication.
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Affiliation(s)
- Raphaelle Laureau
- Department of Genetics and Development, Hammer Health Sciences Center, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Annie Dyatel
- Department of Genetics and Development, Hammer Health Sciences Center, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Gizem Dursuk
- Department of Genetics and Development, Hammer Health Sciences Center, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Samantha Brown
- Department of Genetics and Development, Hammer Health Sciences Center, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Hannah Adeoye
- Department of Genetics and Development, Hammer Health Sciences Center, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Jia-Xing Yue
- Université Côte d'Azur, CNRS, INSERM, IRCAN, Nice 06107, France
| | | | - Anthony Harris
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA 94720, USA
| | - Elçin Ünal
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA 94720, USA
| | - Gianni Liti
- Université Côte d'Azur, CNRS, INSERM, IRCAN, Nice 06107, France
| | - Ian R Adams
- MRC Human Genetics Unit, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, UK
| | - Luke E Berchowitz
- Department of Genetics and Development, Hammer Health Sciences Center, Columbia University Irving Medical Center, New York, NY 10032, USA.
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15
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Qin H, Ni H, Liu Y, Yuan Y, Xi T, Li X, Zheng L. RNA-binding proteins in tumor progression. J Hematol Oncol 2020; 13:90. [PMID: 32653017 PMCID: PMC7353687 DOI: 10.1186/s13045-020-00927-w] [Citation(s) in RCA: 136] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 06/25/2020] [Indexed: 02/08/2023] Open
Abstract
RNA-binding protein (RBP) has a highly dynamic spatiotemporal regulation process and important biological functions. They are critical to maintain the transcriptome through post-transcriptionally controlling the processing and transportation of RNA, including regulating RNA splicing, polyadenylation, mRNA stability, mRNA localization, and translation. Alteration of each process will affect the RNA life cycle, produce abnormal protein phenotypes, and thus lead to the occurrence and development of tumors. Here, we summarize RBPs involved in tumor progression and the underlying molecular mechanisms whereby they are regulated and exert their effects. This analysis is an important step towards the comprehensive characterization of post-transcriptional gene regulation involved in tumor progression.
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Affiliation(s)
- Hai Qin
- School of Life Science and Technology, Jiangsu Key Laboratory of Carcinogenesis and Intervention, China Pharmaceutical University, 639 Longmian Road, Nanjing, 211198, People's Republic of China
| | - Haiwei Ni
- School of Life Science and Technology, Jiangsu Key Laboratory of Carcinogenesis and Intervention, China Pharmaceutical University, 639 Longmian Road, Nanjing, 211198, People's Republic of China
| | - Yichen Liu
- School of Life Science and Technology, Jiangsu Key Laboratory of Carcinogenesis and Intervention, China Pharmaceutical University, 639 Longmian Road, Nanjing, 211198, People's Republic of China
| | - Yaqin Yuan
- Guizhou Medical Device Testing Center, Guiyang, 550004, Guizhou, People's Republic of China
| | - Tao Xi
- School of Life Science and Technology, Jiangsu Key Laboratory of Carcinogenesis and Intervention, China Pharmaceutical University, 639 Longmian Road, Nanjing, 211198, People's Republic of China.
| | - Xiaoman Li
- Jiangsu Key Laboratory for Pharmacology and Safety Evaluation of Chinese Materia Medica, School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, 210023, People's Republic of China.
| | - Lufeng Zheng
- School of Life Science and Technology, Jiangsu Key Laboratory of Carcinogenesis and Intervention, China Pharmaceutical University, 639 Longmian Road, Nanjing, 211198, People's Republic of China.
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16
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Lin K, Qiang W, Zhu M, Ding Y, Shi Q, Chen X, Zsiros E, Wang K, Yang X, Kurita T, Xu EY. Mammalian Pum1 and Pum2 Control Body Size via Translational Regulation of the Cell Cycle Inhibitor Cdkn1b. Cell Rep 2020; 26:2434-2450.e6. [PMID: 30811992 PMCID: PMC6444939 DOI: 10.1016/j.celrep.2019.01.111] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2018] [Revised: 12/20/2018] [Accepted: 01/29/2019] [Indexed: 11/24/2022] Open
Abstract
Body and organ size regulation in mammals involves multiple signaling pathways and remains largely enigmatic. Here, we report that Pum1 and Pum2, which encode highly conserved PUF RNA-binding proteins, regulate mouse body and organ size by post-transcriptional repression of the cell cycle inhibitor Cdkn1b. Binding of PUM1 or PUM2 to Pumilio binding elements (PBEs) in the 3’ UTR of Cdkn1b inhibits translation, promoting G1-S transition and cell proliferation. Mice with null mutations in Pum1 and Pum2 exhibit gene dosage-dependent reductions in body and organ size, and deficiency for Cdkn1b partially rescues postnatal growth defects in Pum1−/− mice. We propose that coordinated tissue-specific expression of Pum1 and Pum2, which involves auto-regulatory and reciprocal post-transcriptional repression, contributes to the precise regulation of body and organ size. Hence PUM-mediated post-transcriptional control of cell cycle regulators represents an additional layer of control in the genetic regulation of organ and body size. Lin et al. show that the RNA-binding proteins PUM1 and PUM2 regulate translation of cell cycle proteins such as CDKN1B by binding to their 3’ UTR and achieve precise control of organ and body size in a gene dosage-sensitive manner via auto and reciprocal gene expression regulation.
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Affiliation(s)
- Kaibo Lin
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing 211166, China
| | - Wenan Qiang
- Department of Obstetrics and Gynecology (Reproductive Science in Medicine), Center for Developmental Therapeutics, Northwestern University, Chicago, IL 60611, USA
| | - Mengyi Zhu
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing 211166, China
| | - Yan Ding
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing 211166, China
| | - Qinghua Shi
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing 211166, China
| | - Xia Chen
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing 211166, China
| | - Emese Zsiros
- Department of Obstetrics and Gynecology (Reproductive Science in Medicine), Center for Developmental Therapeutics, Northwestern University, Chicago, IL 60611, USA
| | - Kun Wang
- Department of Chemistry, Nanjing Normal University, Nanjing 210023, China
| | - Xiaodi Yang
- Department of Chemistry, Nanjing Normal University, Nanjing 210023, China
| | - Takeshi Kurita
- Department of Cancer Biology and Genetics, The Ohio State University Comprehensive Cancer Center, Columbus, OH 43210, USA
| | - Eugene Yujun Xu
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing 211166, China.
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17
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Abstract
The coordinated activities of many protein kinases, acting on multiple protein substrates, ensures the error-free progression through mitosis of eukaryotic cells. Enormous research effort has thus been devoted to studying the roles and regulation of these mitotic kinases, and to the identification of their physiological substrates. Central for the timely deployment of specific protein kinases to their appropriate substrates during the cell division cycle are the many anchoring proteins, which serve critical regulatory roles. Through direct association, anchoring proteins are capable of modulating the catalytic activity and/or sub-cellular distribution of the mitotic kinases they associate with. The key roles of some anchoring proteins in cell division are well-established, whilst others are still being unearthed. Here, we review the current knowledge on anchoring proteins for some mitotic kinases, and highlight how targeting anchoring proteins for inhibition, instead of the mitotic kinases themselves, could be advantageous for disrupting the cell division cycle.
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Affiliation(s)
- Luke J Fulcher
- Medical Research Council Protein Phosphorylation and Ubiquitylation Unit, University of Dundee, Dundee, Scotland, UK
| | - Gopal P Sapkota
- Medical Research Council Protein Phosphorylation and Ubiquitylation Unit, University of Dundee, Dundee, Scotland, UK
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18
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Brocard M, Khasnis S, Wood CD, Shannon-Lowe C, West MJ. Pumilio directs deadenylation-associated translational repression of the cyclin-dependent kinase 1 activator RGC-32. Nucleic Acids Res 2019; 46:3707-3725. [PMID: 29385536 PMCID: PMC5909466 DOI: 10.1093/nar/gky038] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Accepted: 01/22/2018] [Indexed: 12/11/2022] Open
Abstract
Response gene to complement-32 (RGC-32) activates cyclin-dependent kinase 1, regulates the cell cycle and is deregulated in many human tumours. We previously showed that RGC-32 expression is upregulated by the cancer-associated Epstein-Barr virus (EBV) in latently infected B cells through the relief of translational repression. We now show that EBV infection of naïve primary B cells also induces RGC-32 protein translation. In EBV-immortalised cell lines, we found that RGC-32 depletion resulted in cell death, indicating a key role in B cell survival. Studying RGC-32 translational control in EBV-infected cells, we found that the RGC-32 3′untranslated region (3′UTR) mediates translational repression. Repression was dependent on a single Pumilio binding element (PBE) adjacent to the polyadenylation signal. Mutation of this PBE did not affect mRNA cleavage, but resulted in increased polyA tail length. Consistent with Pumilio-dependent recruitment of deadenylases, we found that depletion of Pumilio in EBV-infected cells increased RGC-32 protein expression and polyA tail length. The extent of Pumilio binding to the endogenous RGC-32 mRNA in EBV-infected cell lines also correlated with RGC-32 protein expression. Our data demonstrate the importance of RGC-32 for the survival of EBV-immortalised B cells and identify Pumilio as a key regulator of RGC-32 translation.
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Affiliation(s)
- Michèle Brocard
- School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9QG, UK
| | - Sarika Khasnis
- School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9QG, UK
| | - C David Wood
- School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9QG, UK
| | - Claire Shannon-Lowe
- Institute of Immunology and Immunotherapy, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Michelle J West
- School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9QG, UK
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19
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Anda S, Grallert B. Cell-Cycle-Dependent Regulation of Translation: New Interpretations of Old Observations in Light of New Approaches. Bioessays 2019; 41:e1900022. [PMID: 31210378 DOI: 10.1002/bies.201900022] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 04/29/2019] [Indexed: 12/22/2022]
Abstract
It is a long-standing view that global translation varies during the cell cycle and is much lower in mitosis than in other cell-cycle phases. However, the central papers in the literature are not in agreement about the extent of downregulation in mitosis, ranging from a dramatic decrease to only a marginal reduction. Herein, it is argued that the discrepancy derives from technical challenges. Cell-cycle-dependent variations are most conveniently studied in synchronized cells, but the synchronization methods by themselves often evoke stress responses that, in turn, affect translation rates. Further, it is argued that previously reported cell-cycle-dependent changes in the global translation rate to a large extent reflect responses to the synchronization methods. Recent findings strongly suggest that the global translation rate is not regulated in a cell-cycle-dependent manner. Novel techniques allowing a genome-wide analysis of translational profiles suggest that the extent and importance of selective translational regulation associated with cell-cycle transitions have been underestimated. Therefore, the main question is which messenger RNAs (mRNAs) are translated, rather than whether the global translation rate is decreased.
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Affiliation(s)
- Silje Anda
- Department of Radiation Biology, Institute for Cancer Research, Oslo University Hospital, 0379, Oslo, Norway
| | - Beáta Grallert
- Department of Radiation Biology, Institute for Cancer Research, Oslo University Hospital, 0379, Oslo, Norway
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20
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Poornima G, Mythili R, Nag P, Parbin S, Verma PK, Hussain T, Rajyaguru PI. RGG-motif self-association regulates eIF4G-binding translation repressor protein Scd6. RNA Biol 2019; 16:1215-1227. [PMID: 31157589 PMCID: PMC6693564 DOI: 10.1080/15476286.2019.1621623] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
Regulation of mRNA translation plays a key role in the control of gene expression. Scd6, a conserved RGG-motif containing protein represses translation by binding to translation initiation factor eIF4G1. Here we report that Scd6 binds itself in RGG-motif dependent manner and self-association regulates its repression activity. Scd6 self-interaction competes with eIF4G1 binding and methylation of Scd6 RGG-motif by Hmt1 negatively affects self-association. Results pertaining to Sbp1 indicate that self-association could be a general feature of RGG-motif containing translation repressor proteins. Taken together, our study reveals a mechanism of regulation of eIF4G-binding RGG-motif translation repressors.
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Affiliation(s)
| | - Ravishankar Mythili
- a Department of Biochemistry, Indian Institute of Science , Bangalore , India.,b Department of Biology, University of Western Ontario , London , Canada
| | - Priyabrata Nag
- c Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science , Bangalore , India
| | - Sabnam Parbin
- a Department of Biochemistry, Indian Institute of Science , Bangalore , India
| | - Praveen Kumar Verma
- a Department of Biochemistry, Indian Institute of Science , Bangalore , India
| | - Tanweer Hussain
- c Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science , Bangalore , India
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21
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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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22
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IMOTO Y, ABE Y, OKUMOTO K, OHNUMA M, KUROIWA H, KUROIWA T, FUJIKI Y. Dynamics of the nucleoside diphosphate kinase protein DYNAMO2 correlates with the changes in the global GTP level during the cell cycle of Cyanidioschyzon merolae. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2019; 95:75-85. [PMID: 30745504 PMCID: PMC6403433 DOI: 10.2183/pjab.95.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Accepted: 12/17/2018] [Indexed: 06/09/2023]
Abstract
GTP is an essential source of energy that supports a large array of cellular mechanochemical structures ranging from protein synthesis machinery to cytoskeletal apparatus for maintaining the cell cycle. However, GTP regulation during the cell cycle has been difficult to investigate because of heterogenous levels of GTP in asynchronous cell cycles and genetic redundancy of the GTP-generating enzymes. Here, in the unicellular red algae Cyanidioschyzon merolae, we demonstrated that the ATP-GTP-converting enzyme DYNAMO2 is an essential regulator of global GTP levels during the cell cycle. The cell cycle of C. merolae can be highly synchronized by light/dark stimulations to examine GTP levels at desired time points. Importantly, the genome of C. merolae encodes only two isoforms of the ATP-GTP-converting enzyme, namely DYNAMO1 and DYNAMO2. DYNAMO1 regulates organelle divisions, whereas DYNAMO2 is entirely localized in the cytoplasm. DYNAMO2 protein levels increase during the S-M phases, and changes in GTP levels are correlated with these DYNAMO2 protein levels. These results indicate that DYNAMO2 is a potential regulator of global GTP levels during the cell cycle.
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Affiliation(s)
- Yuuta IMOTO
- Division of Organelle Homeostasis, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Yuichi ABE
- Division of Organelle Homeostasis, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan
| | - Kanji OKUMOTO
- Department of Biology, Faculty of Sciences, Kyushu University, Fukuoka, Japan
| | - Mio OHNUMA
- Institute of Technology, Hiroshima College, Hiroshima, Japan
| | - Haruko KUROIWA
- Department of Chemical and Biological Science, Faculty of Science, Japan Women’s University, Tokyo, Japan
| | - Tsuneyoshi KUROIWA
- Department of Chemical and Biological Science, Faculty of Science, Japan Women’s University, Tokyo, Japan
| | - Yukio FUJIKI
- Division of Organelle Homeostasis, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan
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23
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Xu M, Fang S, Song J, Chen M, Zhang Q, Weng Q, Fan X, Chen W, Wu X, Wu F, Tu J, Zhao Z, Ji J. CPEB1 mediates hepatocellular carcinoma cancer stemness and chemoresistance. Cell Death Dis 2018; 9:957. [PMID: 30237545 PMCID: PMC6148052 DOI: 10.1038/s41419-018-0974-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 08/01/2018] [Accepted: 08/20/2018] [Indexed: 12/13/2022]
Abstract
Cancer stem cells (CSCs) are a subpopulation of cells within tumors that are believed to possess pluripotent properties and thought to be responsible for tumor initiation, progression, relapse and metastasis. Cytoplasmic polyadenylation element-binding protein 1 (CPEB1), a sequence-specific RNA-binding protein that regulates mRNA polyadenylation and translation, has been linked to cancer progression and metastasis. However, the involvement of CPEB1 in hepatocellular carcinoma (HCC) remains unclear. In this study, we have demonstrated that CPEB1 directly regulates sirtuin 1 (SIRT1) mRNA to mediate cancer stemness in HCC. Cancer stemness was analyzed by self-renewal ability, chemoresistance, metastasis, expression of stemness-related genes and CSC marker-positive cell populations. The results indicate that CPEB1 is downregulated in HCC. Overexpression of CPEB1 dramatically reduced HCC cell stemness, whereas silencing CPEB1 enhances it. Using site-directed mutagenesis, a luciferase reporter assay, and immunoprecipitation, we found that CPEB1 could directly target the 3′-UTR of SIRT1, control poly(A) tail length and suppress its translation to mediate cancer stemness in vitro and in vivo. Overall, our findings suggest that the negative regulation between CPEB1 and SIRT1 contributes to the suppression of cancer stemness in HCC. CPEB1 may have potential as a therapeutic target in HCC.
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Affiliation(s)
- Min Xu
- Key Laboratory of Imaging Diagnosis and Minimally Invasive Intervention Research, The Fifth Affiliated Hospital of Wenzhou Medical University, 323000, Lishui, China.,Department of Radiology, Affiliated Lishui Hospital of Zhejiang University, 323000, Lishui, China
| | - Shiji Fang
- Key Laboratory of Imaging Diagnosis and Minimally Invasive Intervention Research, The Fifth Affiliated Hospital of Wenzhou Medical University, 323000, Lishui, China.,Department of Radiology, Affiliated Lishui Hospital of Zhejiang University, 323000, Lishui, China
| | - Jingjing Song
- Key Laboratory of Imaging Diagnosis and Minimally Invasive Intervention Research, The Fifth Affiliated Hospital of Wenzhou Medical University, 323000, Lishui, China.,Department of Radiology, Affiliated Lishui Hospital of Zhejiang University, 323000, Lishui, China
| | - Minjiang Chen
- Key Laboratory of Imaging Diagnosis and Minimally Invasive Intervention Research, The Fifth Affiliated Hospital of Wenzhou Medical University, 323000, Lishui, China.,Department of Radiology, Affiliated Lishui Hospital of Zhejiang University, 323000, Lishui, China
| | - Qianqian Zhang
- Key Laboratory of Imaging Diagnosis and Minimally Invasive Intervention Research, The Fifth Affiliated Hospital of Wenzhou Medical University, 323000, Lishui, China.,Department of Radiology, Affiliated Lishui Hospital of Zhejiang University, 323000, Lishui, China
| | - Qiaoyou Weng
- Key Laboratory of Imaging Diagnosis and Minimally Invasive Intervention Research, The Fifth Affiliated Hospital of Wenzhou Medical University, 323000, Lishui, China.,Department of Radiology, Affiliated Lishui Hospital of Zhejiang University, 323000, Lishui, China
| | - Xiaoxi Fan
- Key Laboratory of Imaging Diagnosis and Minimally Invasive Intervention Research, The Fifth Affiliated Hospital of Wenzhou Medical University, 323000, Lishui, China.,Department of Radiology, Affiliated Lishui Hospital of Zhejiang University, 323000, Lishui, China
| | - Weiqian Chen
- Key Laboratory of Imaging Diagnosis and Minimally Invasive Intervention Research, The Fifth Affiliated Hospital of Wenzhou Medical University, 323000, Lishui, China.,Department of Radiology, Affiliated Lishui Hospital of Zhejiang University, 323000, Lishui, China
| | - Xulu Wu
- Key Laboratory of Imaging Diagnosis and Minimally Invasive Intervention Research, The Fifth Affiliated Hospital of Wenzhou Medical University, 323000, Lishui, China.,Department of Radiology, Affiliated Lishui Hospital of Zhejiang University, 323000, Lishui, China
| | - Fazong Wu
- Key Laboratory of Imaging Diagnosis and Minimally Invasive Intervention Research, The Fifth Affiliated Hospital of Wenzhou Medical University, 323000, Lishui, China.,Department of Radiology, Affiliated Lishui Hospital of Zhejiang University, 323000, Lishui, China
| | - Jianfei Tu
- Key Laboratory of Imaging Diagnosis and Minimally Invasive Intervention Research, The Fifth Affiliated Hospital of Wenzhou Medical University, 323000, Lishui, China.,Department of Radiology, Affiliated Lishui Hospital of Zhejiang University, 323000, Lishui, China
| | - Zhongwei Zhao
- Key Laboratory of Imaging Diagnosis and Minimally Invasive Intervention Research, The Fifth Affiliated Hospital of Wenzhou Medical University, 323000, Lishui, China. .,Department of Radiology, Affiliated Lishui Hospital of Zhejiang University, 323000, Lishui, China.
| | - Jiansong Ji
- Key Laboratory of Imaging Diagnosis and Minimally Invasive Intervention Research, The Fifth Affiliated Hospital of Wenzhou Medical University, 323000, Lishui, China. .,Department of Radiology, Affiliated Lishui Hospital of Zhejiang University, 323000, Lishui, China.
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24
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Carpenter K, Bell RB, Yunus J, Amon A, Berchowitz LE. Phosphorylation-Mediated Clearance of Amyloid-like Assemblies in Meiosis. Dev Cell 2018; 45:392-405.e6. [PMID: 29738715 DOI: 10.1016/j.devcel.2018.04.001] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 03/05/2018] [Accepted: 04/04/2018] [Indexed: 10/17/2022]
Abstract
Amyloids are fibrous protein assemblies that are often described as irreversible and intrinsically pathogenic. However, yeast cells employ amyloid-like assemblies of the RNA-binding protein Rim4 to control translation during meiosis. Here, we show that multi-site phosphorylation of Rim4 is critical for its regulated disassembly and degradation and that failure to clear Rim4 assemblies interferes with meiotic progression. Furthermore, we identify the protein kinase Ime2 to bring about Rim4 clearance via phosphorylation of Rim4's intrinsically disordered region. Rim4 phosphorylation leads to reversal of its amyloid-like properties and degradation by the proteasome. Our data support a model in which a threshold amount of phosphorylation, rather than modification of critical residues, is required for Rim4 clearance. Our results further demonstrate that at least some amyloid-like assemblies are not as irreversible as previously thought. We propose that the natural pathways by which cells process these structures could be deployed to act on disease-related amyloids.
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Affiliation(s)
- Kayla Carpenter
- Department of Genetics and Development, Columbia University Medical Center, 701 W. 168th Street, Hammer Health Sciences Building, Room 1520, New York, NY 10032, USA
| | - Rachel Brietta Bell
- Department of Genetics and Development, Columbia University Medical Center, 701 W. 168th Street, Hammer Health Sciences Building, Room 1520, New York, NY 10032, USA
| | - Julius Yunus
- Department of Genetics and Development, Columbia University Medical Center, 701 W. 168th Street, Hammer Health Sciences Building, Room 1520, New York, NY 10032, USA
| | - Angelika Amon
- Koch Institute for Integrative Cancer Biology, Massachusetts Institute of Technology, Cambridge, MA, USA; Howard Hughes Medical Institute, Chevy Chase, MD, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Luke Edwin Berchowitz
- Department of Genetics and Development, Columbia University Medical Center, 701 W. 168th Street, Hammer Health Sciences Building, Room 1520, New York, NY 10032, USA; Taub Institute for Research on Alzheimer's and the Aging Brain, New York, NY, USA.
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MAPK signaling couples SCF-mediated degradation of translational regulators to oocyte meiotic progression. Proc Natl Acad Sci U S A 2018; 115:E2772-E2781. [PMID: 29496961 DOI: 10.1073/pnas.1715439115] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
RNA-binding proteins (RBPs) are important regulators of gene expression programs, especially during gametogenesis. How the abundance of particular RBPs is restricted to defined stages of meiosis remains largely elusive. Here, we report a molecular pathway that subjects two nonrelated but broadly evolutionarily conserved translational regulators (CPB-3/CPEB and GLD-1/STAR) to proteosomal degradation in Caenorhabditis elegans germ cells at the transition from pachytene to diplotene of meiotic prophase. Both RBPs are recognized by the same ubiquitin ligase complex, containing the molecular scaffold Cullin-1 and the tumor suppressor SEL-10/FBXW7 as its substrate recognition subunit. Destabilization of either RBP through this Skp, Cullin, F-box-containing complex (SCF) ubiquitin ligase appears to loosen its negative control over established target mRNAs, and presumably depends on a prior phosphorylation of CPB-3 and GLD-1 by MAPK (MPK-1), whose activity increases in mid- to late pachytene to promote meiotic progression and oocyte differentiation. Thus, we propose that the orchestrated degradation of RBPs via MAPK-signaling cascades during germ cell development may act to synchronize meiotic with sexual differentiation gene expression changes.
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Nakama AB, Chou HC, Schneider SQ. The asymmetric cell division machinery in the spiral-cleaving egg and embryo of the marine annelid Platynereis dumerilii. BMC DEVELOPMENTAL BIOLOGY 2017; 17:16. [PMID: 29228898 PMCID: PMC5725810 DOI: 10.1186/s12861-017-0158-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 11/23/2017] [Indexed: 12/29/2022]
Abstract
BACKGROUND Over one third of all animal phyla utilize a mode of early embryogenesis called 'spiral cleavage' to divide the fertilized egg into embryonic cells with different cell fates. This mode is characterized by a series of invariant, stereotypic, asymmetric cell divisions (ACDs) that generates cells of different size and defined position within the early embryo. Astonishingly, very little is known about the underlying molecular machinery to orchestrate these ACDs in spiral-cleaving embryos. Here we identify, for the first time, cohorts of factors that may contribute to early embryonic ACDs in a spiralian embryo. RESULTS To do so we analyzed stage-specific transcriptome data in eggs and early embryos of the spiralian annelid Platynereis dumerilii for the expression of over 50 candidate genes that are involved in (1) establishing cortical domains such as the partitioning defective (par) genes, (2) directing spindle orientation, (3) conveying polarity cues including crumbs and scribble, and (4) maintaining cell-cell adhesion between embryonic cells. In general, each of these cohorts of genes are co-expressed exhibiting high levels of transcripts in the oocyte and fertilized single-celled embryo, with progressively lower levels at later stages. Interestingly, a small number of key factors within each ACD module show different expression profiles with increased early zygotic expression suggesting distinct regulatory functions. In addition, our analysis discovered several highly co-expressed genes that have been associated with specialized neural cell-cell recognition functions in the nervous system. The high maternal contribution of these 'neural' adhesion complexes indicates novel general adhesion functions during early embryogenesis. CONCLUSIONS Spiralian embryos are champions of ACD generating embryonic cells of different size with astonishing accuracy. Our results suggest that the molecular machinery for ACD is already stored as maternal transcripts in the oocyte. Thus, the spiralian egg can be viewed as a totipotent yet highly specialized cell that evolved to execute fast and precise ACDs during spiral cleaving stages. Our survey identifies cohorts of factors in P. dumerilii that are candidates for these molecular mechanisms and their regulation, and sets the stage for a functional dissection of ACD in a spiral-cleaving embryo.
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Affiliation(s)
- Aron B. Nakama
- Department of Genetics, Development and Cell Biology, Iowa State University, 503 Science Hall II, Ames, IA 50011 USA
| | - Hsien-Chao Chou
- Department of Genetics, Development and Cell Biology, Iowa State University, 503 Science Hall II, Ames, IA 50011 USA
- current address: Center for Cancer Research, National Institutes of Health, Bethesda, MD 20894 USA
| | - Stephan Q. Schneider
- Department of Genetics, Development and Cell Biology, Iowa State University, 503 Science Hall II, Ames, IA 50011 USA
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Flora P, Schowalter S, Wong-Deyrup S, DeGennaro M, Nasrallah MA, Rangan P. Transient transcriptional silencing alters the cell cycle to promote germline stem cell differentiation in Drosophila. Dev Biol 2017; 434:84-95. [PMID: 29198563 PMCID: PMC5830152 DOI: 10.1016/j.ydbio.2017.11.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 11/18/2017] [Accepted: 11/27/2017] [Indexed: 12/31/2022]
Abstract
Transcriptional silencing is a conserved process used by embryonic germ cells to repress somatic fate and maintain totipotency and immortality. In Drosophila, this transcriptional silencing is mediated by polar granule component (pgc). Here, we show that in the adult ovary, pgc is required for timely germline stem cell (GSC) differentiation. Pgc is expressed transiently in the immediate GSC daughter (pre-cystoblast), where it mediates a pulse of transcriptional silencing. This transcriptional silencing mediated by pgc indirectly promotes the accumulation of Cyclin B (CycB) and cell cycle progression into late-G2 phase, when the differentiation factor bag of marbles (bam) is expressed. Pgc mediated accumulation of CycB is also required for heterochromatin deposition, which protects the germ line genome against selfish DNA elements. Our results suggest that transient transcriptional silencing in the pre-cystoblast “re-programs” it away from self-renewal and toward the gamete differentiation program.
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Affiliation(s)
- Pooja Flora
- Department of Biological Sciences/The RNA Institute, University at Albany SUNY, Albany, NY 12222, USA
| | - Sean Schowalter
- Department of Biological Sciences/The RNA Institute, University at Albany SUNY, Albany, NY 12222, USA; Boston University School of Medicine, 815 Albany Street, MA 02119, USA
| | - SiuWah Wong-Deyrup
- Department of Biological Sciences/The RNA Institute, University at Albany SUNY, Albany, NY 12222, USA
| | - Matthew DeGennaro
- Biomolecular Sciences Institute, Department of Biological Sciences, Florida International University, Miami, FL 33199, USA
| | - Mohamad Ali Nasrallah
- Department of Biological Sciences/The RNA Institute, University at Albany SUNY, Albany, NY 12222, USA; University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Prashanth Rangan
- Department of Biological Sciences/The RNA Institute, University at Albany SUNY, Albany, NY 12222, USA.
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The 5'-poly(A) leader of poxvirus mRNA confers a translational advantage that can be achieved in cells with impaired cap-dependent translation. PLoS Pathog 2017; 13:e1006602. [PMID: 28854224 PMCID: PMC5595341 DOI: 10.1371/journal.ppat.1006602] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Revised: 09/12/2017] [Accepted: 08/23/2017] [Indexed: 01/11/2023] Open
Abstract
The poly(A) leader at the 5'-untranslated region (5'-UTR) is an unusually striking feature of all poxvirus mRNAs transcribed after viral DNA replication (post-replicative mRNAs). These poly(A) leaders are non-templated and of heterogeneous lengths; and their function during poxvirus infection remains a long-standing question. Here, we discovered that a 5'-poly(A) leader conferred a selective translational advantage to mRNA in poxvirus-infected cells. A constitutive and uninterrupted 5'-poly(A) leader with 12 residues was optimal. Because the most frequent lengths of the 5'-poly(A) leaders are 8-12 residues, the result suggests that the poly(A) leader has been evolutionarily optimized to boost poxvirus protein production. A 5'-poly(A) leader also could increase protein production in the bacteriophage T7 promoter-based expression system of vaccinia virus, the prototypic member of poxviruses. Interestingly, although vaccinia virus post-replicative mRNAs do have 5'- methylated guanosine caps and can use cap-dependent translation, in vaccinia virus-infected cells, mRNA with a 5'-poly(A) leader could also be efficiently translated in cells with impaired cap-dependent translation. However, the translation was not mediated through an internal ribosome entry site (IRES). These results point to a fundamental mechanism poxvirus uses to efficiently translate its post-replicative mRNAs.
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Host Cell S Phase Restricts Legionella pneumophila Intracellular Replication by Destabilizing the Membrane-Bound Replication Compartment. mBio 2017; 8:mBio.02345-16. [PMID: 28830950 PMCID: PMC5565972 DOI: 10.1128/mbio.02345-16] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Legionella pneumophila grows within cells ranging from environmental amoebae to human macrophages. In spite of this conserved strategy of pathogenesis, identification of host factors that restrict L. pneumophila intracellular replication has not been extended outside components of the mammalian innate immune response. We performed a double-stranded RNA (dsRNA) screen against more than 50% of the Drosophila melanogaster annotated open reading frames (ORFs) to identify host cell factors that restrict L. pneumophila. The majority of analyzed dsRNAs that stimulated L. pneumophila intracellular replication were directed against host proteins involved in protein synthesis or cell cycle control. Consistent with disruption of the cell cycle stimulating intracellular replication, proteins involved in translation initiation also resulted in G1 arrest. Stimulation of replication was dependent on the stage of cell cycle arrest, as dsRNAs causing arrest during S phase had an inhibitory effect on intracellular replication. The inhibitory effects of S phase arrest could be recapitulated in a human cell line, indicating that cell cycle control of L. pneumophila replication is evolutionarily conserved. Synchronized HeLa cell populations in S phase and challenged with L. pneumophila failed to progress through the cell cycle and were depressed for supporting intracellular replication. Poor bacterial replication in S phase was associated with loss of the vacuole membrane barrier, resulting in exposure of bacteria to the cytosol and their eventual degradation. These results are consistent with the model that S phase is inhibitory for L. pneumophila intracellular survival as a consequence of failure to maintain the integrity of the membrane surrounding intracellular bacteria. Legionella pneumophila has the ability to replicate within human macrophages and amoebal hosts. Here, we report that the host cell cycle influences L. pneumophila intracellular replication. Our data demonstrate that the G1 and G2/M phases of the host cell cycle are permissive for bacterial replication, while S phase is toxic for the bacterium. L. pneumophila replicates poorly within host cells present in S phase. The inability of L. pneumophila to replicate relies on its failure to control the integrity of its vacuole, leading to cytosolic exposure of the bacteria and eventual degradation. The data presented here argue that growth-arrested host cells that are encountered by L. pneumophila in either the environment or within human hosts are ideal targets for intracellular replication because their transit through S phase is blocked.
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Salton GD, Laurino CCFC, Mega NO, Delgado-Cañedo A, Setterblad N, Carmagnat M, Xavier RM, Cirne-Lima E, Lenz G, Henriques JAP, Laurino JP. Deletion of eIF2β lysine stretches creates a dominant negative that affects the translation and proliferation in human cell line: A tool for arresting the cell growth. Cancer Biol Ther 2017; 18:560-570. [PMID: 28692326 DOI: 10.1080/15384047.2017.1345383] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Eukaryote initiation factor 2 subunit β (eIF2β) plays a crucial role in regulation protein synthesis, which mediates the interaction of eIF2 with mRNA. eIF2β contains evolutionarily conserved polylysine stretches in amino-terminal region and a zinc finger motif in the carboxy-terminus. METHODS The gene eIF2β was cloned under tetracycline transcription control and the polylysine stretches were deleted by site-directed mutagenesis (eIF2βΔ3K). The plasmid was transfected into HEK 293 TetR cells. These cells were analyzed for their proliferative and translation capacities as well as cell death rate. Experiments were performed using gene reporter assays, western blotting, flow cytometry, cell sorting, cell proliferation assays and confocal immunofluorescence. RESULTS eIF2βΔ3K affected negatively the protein synthesis, cell proliferation and cell survival causing G2 cell cycle arrest and increased cell death, acting in a negative dominant manner against the native protein. Polylysine stretches are also essential for eIF2β translocated from the cytoplasm to the nucleus, accumulating in the nucleolus and eIF2βΔ3K did not make this translocation. DISCUSSION eIF2β is involved in the protein synthesis process and should act in nuclear processes as well. eIF2βΔ3K reduces cell proliferation and causes cell death. Since translation control is essential for normal cell function and survival, the development of drugs or molecules that inhibit translation has become of great interest in the scenario of proliferative disorders. In conclusion, our results suggest the dominant negative eIF2βΔ3K as a therapeutic strategy for the treatment of proliferative disorders and that eIF2β polylysine stretch domains are promising targets for this.
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Affiliation(s)
- Gabrielle Dias Salton
- a Post-Graduation Program in Cellular and Molecular Biology, Molecular Radiobiology Laboratory, Biotechnology Center , Universidade Federal do Rio Grande do Sul , Porto Alegre (RS) , Brazil , Cryobiology Unit and Umbilical Cord Blood Bank, Hemotherapy Service , Hospital de Clínicas de Porto Alegre , Porto Alegre (RS) , Brazil
| | - Claudia Cilene Fernandes Correia Laurino
- b Molecular Biology for Auto-immune and Infectious Diseases Laboratory, Experimental Research Center, Hospital de Clínicas de Porto Alegre , Universidade Federal do Rio Grande do Sul , Porto Alegre (RS) , Brazil . Embriology and Cellular Differentiation Laboratory, Experimental Research Center, Hospital de Clínicas de Porto Alegre; Faculdade de Veterinária , Universidade Federal do Rio Grande do Sul , Porto Alegre (RS) , Brazil . Faculdade Nossa Senhora de Fátima , Caxias do Sul (RS) , Brazil . Instituto Brasileiro de Saúde , Porto Alegre (RS) , Brazil
| | - Nicolás Oliveira Mega
- c Animal Biology Post-Graduation Program , Universidade Federal do Rio Grande do Sul , Porto Alegre (RS) , Brazil
| | - Andrés Delgado-Cañedo
- d Biotechnology Research Center for Interdisciplinary Research , Universidade Federal do Pampa , São Gabriel (RS) , Brazil
| | - Niclas Setterblad
- e Imaging, Cell Selection and Genomics Platform , Institut Universitaire d'Hématologie, Hôpital Saint-Louis , Paris , France
| | - Maryvonnick Carmagnat
- f Immunology and Histocompatibility Laboratory AP-HP , INSERM UMRS 940, Institut Universitaire d'Hématologie , Paris , France
| | - Ricardo Machado Xavier
- g Molecular Biology for Auto-immune and Infectious Diseases Laboratory, Experimental Research Center, Hospital de Clínicas de Porto Alegre , Universidade Federal do Rio Grande do Sul , Porto Alegre (RS) , Brazil
| | - Elizabeth Cirne-Lima
- h Embriology and Cellular Differentiation Laboratory, Experimental Research Center, Hospital de Clínicas de Porto Alegre; Faculdade de Veterinária , Universidade Federal do Rio Grande do Sul , Porto Alegre (RS) , Brazil
| | - Guido Lenz
- i Cell Signaling Laboratory, Biophysics Department, Biotechnology Center and Post-Graduation Program in Cellular and Molecular Biology , Universidade Federal do Rio Grande do Sul , Porto Alegre (RS) , Brazil
| | - João Antonio Pêgas Henriques
- j Molecular Radiobiology Laboratory, Biotechnology Center and Post-Graduation Program in Cellular and Molecular Biology , Universidade Federal do Rio Grande do Sul , Porto Alegre (RS) ; Biotechnology Institute , Universidade de Caxias do Sul , Caxias do Sul (RS) , Brazil
| | - Jomar Pereira Laurino
- k Biotechnology Institute , Universidade de Caxias do Sul, Caxias do Sul (RS) and Instituto Brasileiro de Saúde , Porto Alegre (RS) , Brazil
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Hewetson A, Do HQ, Myers C, Muthusubramanian A, Sutton RB, Wylie BJ, Cornwall GA. Functional Amyloids in Reproduction. Biomolecules 2017; 7:biom7030046. [PMID: 28661450 PMCID: PMC5618227 DOI: 10.3390/biom7030046] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Revised: 06/20/2017] [Accepted: 06/23/2017] [Indexed: 11/16/2022] Open
Abstract
Amyloids are traditionally considered pathological protein aggregates that play causative roles in neurodegenerative disease, diabetes and prionopathies. However, increasing evidence indicates that in many biological systems nonpathological amyloids are formed for functional purposes. In this review, we will specifically describe amyloids that carry out biological roles in sexual reproduction including the processes of gametogenesis, germline specification, sperm maturation and fertilization. Several of these functional amyloids are evolutionarily conserved across several taxa, including human, emphasizing the critical role amyloids perform in reproduction. Evidence will also be presented suggesting that, if altered, some functional amyloids may become pathological.
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Affiliation(s)
- Aveline Hewetson
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA.
| | - Hoa Quynh Do
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA.
| | - Caitlyn Myers
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA.
| | - Archana Muthusubramanian
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA.
| | - Roger Bryan Sutton
- Department of Cell Physiology and Molecular Biophysics, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA.
| | - Benjamin J Wylie
- Department of Chemistry, Texas Tech University, Lubbock, TX 79409, USA.
| | - Gail A Cornwall
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA.
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32
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De Pablos LM, Kelly S, de Freitas Nascimento J, Sunter J, Carrington M. Characterization of RBP9 and RBP10, two developmentally regulated RNA-binding proteins in Trypanosoma brucei. Open Biol 2017; 7:rsob.160159. [PMID: 28381627 PMCID: PMC5413900 DOI: 10.1098/rsob.160159] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Accepted: 03/08/2017] [Indexed: 12/19/2022] Open
Abstract
The fate of an mRNA is determined by its interaction with proteins and small RNAs within dynamic complexes called ribonucleoprotein complexes (mRNPs). In Trypanosoma brucei and related kinetoplastids, responses to internal and external signals are mainly mediated by post-transcriptional processes. Here, we used proximity-dependent biotin identification (BioID) combined with RNA-seq to investigate the changes resulting from ectopic expression of RBP10 and RBP9, two developmentally regulated RNA-binding proteins (RBPs). Both RBPs have reduced expression in insect procyclic forms (PCFs) compared with bloodstream forms (BSFs). Upon overexpression in PCFs, both proteins were recruited to cytoplasmic foci, co-localizing with the processing body marker SCD6. Further, both RBPs altered the transcriptome from a PCF- to a BSF-like pattern. Notably, upon expression of BirA*-RBP9 and BirA*-RBP10, BioID yielded more than 200 high confidence protein interactors (more than 10-fold enriched); 45 (RBP9) and 31 (RBP10) were directly related to mRNA metabolism. This study validates the use of BioID for investigating mRNP components but also illustrates the complexity of mRNP function.
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Affiliation(s)
- Luis Miguel De Pablos
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK.,Centre for Immunology and Infection (CII). Biology Dept., University of York, York YO10 5DD, UK
| | - Steve Kelly
- Department of Plant Sciences, University of Oxford, South Parks Road, Oxford OX1 3RB, UK
| | | | - Jack Sunter
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK
| | - Mark Carrington
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
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McCurdy SR, Pacal M, Ahmad M, Bremner R. A CDK2 activity signature predicts outcome in CDK2-low cancers. Oncogene 2016; 36:2491-2502. [DOI: 10.1038/onc.2016.409] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Revised: 08/30/2016] [Accepted: 09/23/2016] [Indexed: 12/21/2022]
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Onichtchouk DV, Voronina AS. Regulation of Zygotic Genome and Cellular Pluripotency. BIOCHEMISTRY (MOSCOW) 2016; 80:1723-33. [PMID: 26878577 DOI: 10.1134/s0006297915130088] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Events, manifesting transition from maternal to zygotic period of development are studied for more than 100 years, but underlying mechanisms are not yet clear. We provide a brief historical overview of development of concepts and explain the specific terminology used in the field. We further discuss differences and similarities between the zygotic genome activation and in vitro reprogramming process. Finally, we envision the future research directions within the field, where biochemical methods will play increasingly important role.
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Affiliation(s)
- D V Onichtchouk
- University of Freiburg, Developmental Biology Unit, Biologie 1, Freiburg, 79194, Germany.
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Lu Z, Sessler F, Holroyd N, Hahnel S, Quack T, Berriman M, Grevelding CG. Schistosome sex matters: a deep view into gonad-specific and pairing-dependent transcriptomes reveals a complex gender interplay. Sci Rep 2016; 6:31150. [PMID: 27499125 PMCID: PMC4976352 DOI: 10.1038/srep31150] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Accepted: 07/12/2016] [Indexed: 12/25/2022] Open
Abstract
As a key event for maintaining life cycles, reproduction is a central part of platyhelminth biology. In case of parasitic platyhelminths, reproductive processes can also contribute to pathology. One representative example is the trematode Schistosoma, which causes schistosomiasis, an infectious disease, whose pathology is associated with egg production. Among the outstanding features of schistosomes is their dioecious lifestyle and the pairing-dependent differentiation of the female gonads which finally leads to egg synthesis. To analyze the reproductive biology of Schistosoma mansoni in-depth we isolated complete ovaries and testes from paired and unpaired schistosomes for comparative RNA-seq analyses. Of >7,000 transcripts found in the gonads, 243 (testes) and 3,600 (ovaries) occurred pairing-dependently. Besides the detection of genes transcribed preferentially or specifically in the gonads of both genders, we uncovered pairing-induced processes within the gonads including stem cell-associated and neural functions. Comparisons to work on neuropeptidergic signaling in planarian showed interesting parallels but also remarkable differences and highlights the importance of the nervous system for flatworm gonad differentiation. Finally, we postulated first functional hints for 235 hypothetical genes. Together, these results elucidate key aspects of flatworm reproductive biology and will be relevant for basic as well as applied, exploitable research aspects.
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Affiliation(s)
- Zhigang Lu
- BFS, Institute of Parasitology, Justus-Liebig-University, Giessen, Germany
| | - Florian Sessler
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, United Kingdom
| | - Nancy Holroyd
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, United Kingdom
| | - Steffen Hahnel
- BFS, Institute of Parasitology, Justus-Liebig-University, Giessen, Germany
| | - Thomas Quack
- BFS, Institute of Parasitology, Justus-Liebig-University, Giessen, Germany
| | - Matthew Berriman
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, United Kingdom
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Guan C, Zhang J, Zhang J, Shi H, Ni R. Enhanced expression of early mitotic inhibitor-1 predicts a poor prognosis in esophageal squamous cell carcinoma patients. Oncol Lett 2016; 12:114-120. [PMID: 27347110 PMCID: PMC4906579 DOI: 10.3892/ol.2016.4611] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Accepted: 04/08/2016] [Indexed: 01/15/2023] Open
Abstract
Early mitotic inhibitor-1 (Emi1), as a key cell cycle regulatory gene, induces S phase and mitotic entry by controlling anaphase-promoting complex substrates. Emi1 overexpression may be a prognostic factor for patients with invasive breast cancer. However, its expression and clinical significance in esophageal squamous cell carcinoma (ESCC) remain unknown. In the present study, Emi1 was overexpressed in ESCC samples, contrarily to their neighboring normal tissues. The expression of Emi1 was correlated with histological differentiation (P=0.032), lymphatic metastasis (P=0.006) and Ki-67 expression (P=0.028). Multivariate analysis indicated that the presence of lymphatic metastasis and the protein expression levels of Emi1 and Ki-67 were all independent prognostic factors for ESCC patients (P=0.042, 0.018 and 0.001, respectively). In vitro, however, the expression of Emi1 was upregulated in the ECA109 cell line following release from serum starvation. In addition, depletion of endogenous Emi1 by small interfering RNA could effectively reduce cell proliferation. Thus, the present data indicated that Emi1 expression was upregulated in ESCC tissues and correlated with poor survival in ESCC patients, and suggested that Emi1 may be an independent prognostic factor for ESCC patients.
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Affiliation(s)
- Chengqi Guan
- Department of Gastroenterology, Affiliated Hospital of Nantong University, Nantong, Jiangsu 226001, P.R. China
| | - Jianfeng Zhang
- Department of Gastroenterology, Affiliated Hospital of Nantong University, Nantong, Jiangsu 226001, P.R. China
| | - Jianguo Zhang
- Department of Pathology, Affiliated Hospital of Nantong University, Nantong, Jiangsu 226001, P.R. China
| | - Hui Shi
- Department of Thoracic Surgery, Affiliated Hospital of Nantong University, Nantong, Jiangsu 226001, P.R. China
| | - Runzhou Ni
- Department of Gastroenterology, Affiliated Hospital of Nantong University, Nantong, Jiangsu 226001, P.R. China
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Chassé H, Mulner-Lorillon O, Boulben S, Glippa V, Morales J, Cormier P. Cyclin B Translation Depends on mTOR Activity after Fertilization in Sea Urchin Embryos. PLoS One 2016; 11:e0150318. [PMID: 26962866 PMCID: PMC4786324 DOI: 10.1371/journal.pone.0150318] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Accepted: 02/11/2016] [Indexed: 12/11/2022] Open
Abstract
The cyclin B/CDK1 complex is a key regulator of mitotic entry. Using PP242, a specific ATP-competitive inhibitor of mTOR kinase, we provide evidence that the mTOR signalling pathway controls cyclin B mRNA translation following fertilization in Sphaerechinus granularis and Paracentrotus lividus. We show that PP242 inhibits the degradation of the cap-dependent translation repressor 4E-BP (eukaryotic initiation factor 4E-Binding Protein). PP242 inhibits global protein synthesis, delays cyclin B accumulation, cyclin B/CDK1 complex activation and consequently entry into the mitotic phase of the cell cycle triggered by fertilization. PP242 inhibits cyclin B mRNA recruitment into active polysomes triggered by fertilization. An amount of cyclin B mRNA present in active polysomes appears to be insensitive to PP242 treatment. Taken together, our results suggest that, following sea urchin egg fertilization, cyclin B mRNA translation is controlled by two independent mechanisms: a PP242-sensitive and an additional PP242-insentitive mechanism.
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Affiliation(s)
- Héloïse Chassé
- Sorbonne Universités, UPMC Univ Paris 06, UMR 8227, Integrative Biology of Marine Models, Translation Cell Cycle and Development, Station Biologique de Roscoff, CS 90074, F-29688, Roscoff cedex, France
- CNRS, UMR 8227, Integrative Biology of Marine Models, Station Biologique de Roscoff, CS 90074, F-29688, Roscoff cedex, France
| | - Odile Mulner-Lorillon
- Sorbonne Universités, UPMC Univ Paris 06, UMR 8227, Integrative Biology of Marine Models, Translation Cell Cycle and Development, Station Biologique de Roscoff, CS 90074, F-29688, Roscoff cedex, France
- CNRS, UMR 8227, Integrative Biology of Marine Models, Station Biologique de Roscoff, CS 90074, F-29688, Roscoff cedex, France
- * E-mail: (PC); (JM); (OML)
| | - Sandrine Boulben
- Sorbonne Universités, UPMC Univ Paris 06, UMR 8227, Integrative Biology of Marine Models, Translation Cell Cycle and Development, Station Biologique de Roscoff, CS 90074, F-29688, Roscoff cedex, France
- CNRS, UMR 8227, Integrative Biology of Marine Models, Station Biologique de Roscoff, CS 90074, F-29688, Roscoff cedex, France
| | - Virginie Glippa
- Sorbonne Universités, UPMC Univ Paris 06, UMR 8227, Integrative Biology of Marine Models, Translation Cell Cycle and Development, Station Biologique de Roscoff, CS 90074, F-29688, Roscoff cedex, France
- CNRS, UMR 8227, Integrative Biology of Marine Models, Station Biologique de Roscoff, CS 90074, F-29688, Roscoff cedex, France
| | - Julia Morales
- Sorbonne Universités, UPMC Univ Paris 06, UMR 8227, Integrative Biology of Marine Models, Translation Cell Cycle and Development, Station Biologique de Roscoff, CS 90074, F-29688, Roscoff cedex, France
- CNRS, UMR 8227, Integrative Biology of Marine Models, Station Biologique de Roscoff, CS 90074, F-29688, Roscoff cedex, France
- * E-mail: (PC); (JM); (OML)
| | - Patrick Cormier
- Sorbonne Universités, UPMC Univ Paris 06, UMR 8227, Integrative Biology of Marine Models, Translation Cell Cycle and Development, Station Biologique de Roscoff, CS 90074, F-29688, Roscoff cedex, France
- CNRS, UMR 8227, Integrative Biology of Marine Models, Station Biologique de Roscoff, CS 90074, F-29688, Roscoff cedex, France
- * E-mail: (PC); (JM); (OML)
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Zur H, Aviner R, Tuller T. Complementary Post Transcriptional Regulatory Information is Detected by PUNCH-P and Ribosome Profiling. Sci Rep 2016; 6:21635. [PMID: 26898226 PMCID: PMC4761937 DOI: 10.1038/srep21635] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Accepted: 01/27/2016] [Indexed: 01/09/2023] Open
Abstract
Two novel approaches were recently suggested for genome-wide identification of protein aspects synthesized at a given time. Ribo-Seq is based on sequencing all the ribosome protected mRNA fragments in a cell, while PUNCH-P is based on mass-spectrometric analysis of only newly synthesized proteins. Here we describe the first Ribo-Seq/PUNCH-P comparison via the analysis of mammalian cells during the cell-cycle for detecting relevant differentially expressed genes between G1 and M phase. Our analyses suggest that the two approaches significantly overlap with each other. However, we demonstrate that there are biologically meaningful proteins/genes that can be detected to be post-transcriptionally regulated during the mammalian cell cycle only by each of the approaches, or their consolidation. Such gene sets are enriched with proteins known to be related to intra-cellular signalling pathways such as central cell cycle processes, central gene expression regulation processes, processes related to chromosome segregation, DNA damage, and replication, that are post-transcriptionally regulated during the mammalian cell cycle. Moreover, we show that combining the approaches better predicts steady state changes in protein abundance. The results reported here support the conjecture that for gaining a full post-transcriptional regulation picture one should integrate the two approaches.
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Affiliation(s)
- Hadas Zur
- Department of Biomedical Engineering, the Engineering Faculty, Tel Aviv University, Israel
| | - Ranen Aviner
- Department of Cell Research and Immunology, Tel Aviv University, Israel
| | - Tamir Tuller
- Department of Biomedical Engineering, the Engineering Faculty, Tel Aviv University, Israel.,The Sagol School of Neuroscience, Tel Aviv University, Israel
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Peguero-Sanchez E, Pardo-Lopez L, Merino E. IRES-dependent translated genes in fungi: computational prediction, phylogenetic conservation and functional association. BMC Genomics 2015; 16:1059. [PMID: 26666532 PMCID: PMC4678720 DOI: 10.1186/s12864-015-2266-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Accepted: 12/01/2015] [Indexed: 01/17/2023] Open
Abstract
Background The initiation of translation via cellular internal ribosome entry sites plays an important role in the stress response and certain physiological conditions in which canonical cap-dependent translation initiation is compromised. Currently, only a limited number of these regulatory elements have been experimentally identified. Notably, cellular internal ribosome entry sites lack conservation of both the primary sequence and mRNA secondary structure, rendering their identification difficult. Despite their biological importance, the currently available computational strategies to predict them have had limited success. We developed a bioinformatic method based on a support vector machine for the prediction of internal ribosome entry sites in fungi using the 5’-UTR sequences of 20 non-redundant fungal organisms. Additionally, we performed a comparative analysis and characterization of the functional relationships among the gene products predicted to be translated by this cap-independent mechanism. Results Using our method, we predicted 6,532 internal ribosome entry sites in 20 non-redundant fungal organisms. Some orthologous groups were enriched with our positive predictions. This is the case of the HSP70 chaperone family, which remarkably has two verified internal ribosome entry sites, one in humans and the other in flies. A second example is the orthologous group of the eIF4G repression protein Sbp1p, which has two homologous genes known to be translated by this cap-independent mechanism, one in mice and the other in yeast. These examples emphasize the wide conservation of these regulatory elements as a result of selective pressure. In addition, we performed a protein-protein interaction network characterization of the gene products of our positive predictions using Saccharomyces cerevisiae as a model, which revealed a highly connected and modular topology, suggesting a functional association. A remarkable example of this functional association is our prediction of internal ribosome entry sites elements in three components of the RNA polymerase II mediator complex. Conclusions We developed a method for the prediction of cellular internal ribosome entry sites that may guide experimental and bioinformatic analyses to increase our understanding of protein translation regulation. Our analysis suggests that fungi show evolutionary conservation and functional association of proteins translated by this cap-independent mechanism. Electronic supplementary material The online version of this article (doi:10.1186/s12864-015-2266-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Esteban Peguero-Sanchez
- Departamento de Microbiología Molecular, Instituto de Biotecnología, UNAM, Av. Universidad 2001, Cuernavaca, Morelos, CP 62210, Mexico.
| | - Liliana Pardo-Lopez
- Departamento de Microbiología Molecular, Instituto de Biotecnología, UNAM, Av. Universidad 2001, Cuernavaca, Morelos, CP 62210, Mexico.
| | - Enrique Merino
- Departamento de Microbiología Molecular, Instituto de Biotecnología, UNAM, Av. Universidad 2001, Cuernavaca, Morelos, CP 62210, Mexico.
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40
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Berchowitz LE, Kabachinski G, Walker MR, Carlile TM, Gilbert WV, Schwartz TU, Amon A. Regulated Formation of an Amyloid-like Translational Repressor Governs Gametogenesis. Cell 2015; 163:406-18. [PMID: 26411291 DOI: 10.1016/j.cell.2015.08.060] [Citation(s) in RCA: 125] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2015] [Revised: 06/28/2015] [Accepted: 08/17/2015] [Indexed: 11/25/2022]
Abstract
Message-specific translational control is required for gametogenesis. In yeast, the RNA-binding protein Rim4 mediates translational repression of numerous mRNAs, including the B-type cyclin CLB3, which is essential for establishing the meiotic chromosome segregation pattern. Here, we show that Rim4 forms amyloid-like aggregates and that it is the amyloid-like form of Rim4 that is the active, translationally repressive form of the protein. Our data further show that Rim4 aggregation is a developmentally regulated process. Starvation induces the conversion of monomeric Rim4 into amyloid-like aggregates, thereby activating the protein to bring about repression of translation. At the onset of meiosis II, Rim4 aggregates are abruptly degraded allowing translation to commence. Although amyloids are best known for their role in the etiology of diseases such as Alzheimer's, Parkinson's, and diabetes by forming toxic protein aggregates, our findings show that cells can utilize amyloid-like protein aggregates to function as central regulators of gametogenesis.
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Affiliation(s)
- Luke E Berchowitz
- David H. Koch Institute for Integrative Cancer Research and Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Greg Kabachinski
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139 USA
| | - Margaret R Walker
- David H. Koch Institute for Integrative Cancer Research and Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Thomas M Carlile
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139 USA
| | - Wendy V Gilbert
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139 USA
| | - Thomas U Schwartz
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139 USA
| | - Angelika Amon
- David H. Koch Institute for Integrative Cancer Research and Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139 USA.
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Tanenbaum ME, Stern-Ginossar N, Weissman JS, Vale RD. Regulation of mRNA translation during mitosis. eLife 2015; 4. [PMID: 26305499 PMCID: PMC4548207 DOI: 10.7554/elife.07957] [Citation(s) in RCA: 112] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Accepted: 08/02/2015] [Indexed: 12/21/2022] Open
Abstract
Passage through mitosis is driven by precisely-timed changes in transcriptional regulation and protein degradation. However, the importance of translational regulation during mitosis remains poorly understood. Here, using ribosome profiling, we find both a global translational repression and identified ∼200 mRNAs that undergo specific translational regulation at mitotic entry. In contrast, few changes in mRNA abundance are observed, indicating that regulation of translation is the primary mechanism of modulating protein expression during mitosis. Interestingly, 91% of the mRNAs that undergo gene-specific regulation in mitosis are translationally repressed, rather than activated. One of the most pronounced translationally-repressed genes is Emi1, an inhibitor of the anaphase promoting complex (APC) which is degraded during mitosis. We show that full APC activation requires translational repression of Emi1 in addition to its degradation. These results identify gene-specific translational repression as a means of controlling the mitotic proteome, which may complement post-translational mechanisms for inactivating protein function. DOI:http://dx.doi.org/10.7554/eLife.07957.001 The human body contains billions of cells, most of which formed via a process called mitosis in which a single cell divides to produce two new daughter cells. Actively dividing cells pass through a series of events (or phases) that are collectively known as the cell cycle. These phases allow the cell to grow in size, copy its genetic material, and then make preparations for cell division before taking the final decision to divide. Many proteins are involved in regulating the cell cycle and each protein has a particular role in specific phases. The levels of these proteins in cells may change during the cycle, which is often crucial to allow the cell to progress to the next phase. For example, cells need a group of proteins called the anaphase-promoting complex (or APC for short) to destroy other specific proteins at the end of mitosis. Another way in which the amount of protein in a cell can be adjusted is by controlling how much new protein is made during a process known as translation. During this process, a molecule called a messenger RNA (mRNA)—which contains information copied from a particular gene—is used as a template to assemble a new protein. However, it is not clear whether regulation of translation is involved in control of the cell division. Tanenbaum et al. now address this question using a technique called ribosome profiling to measure the translation of individual mRNA molecules. The experiments analysed the changes in protein production before, during and after mitosis. The overall level of translation of all the mRNAs was about 35% lower during mitosis. However, some mRNAs in particular experienced a very large reduction in the level of translation (between three- and ten-fold less than the levels before mitosis). One example of an mRNA whose translation is turned off in mitosis is the mRNA that makes a protein called Emi1. It is known from previous work that Emi1 inhibits the activity of the APC. Therefore, Emi1 needs to be inactivated in mitosis so that the APC can become active and promote progression to the next phase of the cell cycle. It was previously shown that Emi1 is destroyed during mitosis to allow the APC to operate. Tanenbaum et al. found that translation of the Emi1 mRNA must also be suppressed during mitosis in order to keep Emi1 protein levels very low and allow the APC to become fully active. These findings uncover a new role for the control of protein production in regulating the cell cycle. The next challenge will be to find out whether suppression of translation is also used in other biological systems where proteins need to be rapidly inactivated. DOI:http://dx.doi.org/10.7554/eLife.07957.002
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Affiliation(s)
- Marvin E Tanenbaum
- Department of Cellular and Molecular Pharmacology, Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, United States
| | - Noam Stern-Ginossar
- Department of Cellular and Molecular Pharmacology, Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, United States
| | - Jonathan S Weissman
- Department of Cellular and Molecular Pharmacology, Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, United States
| | - Ronald D Vale
- Department of Cellular and Molecular Pharmacology, Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, United States
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Silva RC, Dautel M, Di Genova BM, Amberg DC, Castilho BA, Sattlegger E. The Gcn2 Regulator Yih1 Interacts with the Cyclin Dependent Kinase Cdc28 and Promotes Cell Cycle Progression through G2/M in Budding Yeast. PLoS One 2015; 10:e0131070. [PMID: 26176233 PMCID: PMC4503747 DOI: 10.1371/journal.pone.0131070] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2014] [Accepted: 05/28/2015] [Indexed: 12/01/2022] Open
Abstract
The Saccharomyces cerevisiae protein Yih1, when overexpressed, inhibits the eIF2 alpha kinase Gcn2 by competing for Gcn1 binding. However, deletion of YIH1 has no detectable effect on Gcn2 activity, suggesting that Yih1 is not a general inhibitor of Gcn2, and has no phenotypic defect identified so far. Thus, its physiological role is largely unknown. Here, we show that Yih1 is involved in the cell cycle. Yeast lacking Yih1 displays morphological patterns and DNA content indicative of a delay in the G2/M phases of the cell cycle, and this phenotype is independent of Gcn1 and Gcn2. Accordingly, the levels of phosphorylated eIF2α, which show a cell cycle-dependent fluctuation, are not altered in cells devoid of Yih1. We present several lines of evidence indicating that Yih1 is in a complex with Cdc28. Yih1 pulls down endogenous Cdc28 in vivo and this interaction is enhanced when Cdc28 is active, suggesting that Yih1 modulates the function of Cdc28 in specific stages of the cell cycle. We also demonstrate, by Bimolecular Fluorescence Complementation, that endogenous Yih1 and Cdc28 interact with each other, confirming Yih1 as a bona fide Cdc28 binding partner. Amino acid substitutions within helix H2 of the RWD domain of Yih1 enhance Yih1-Cdc28 association. Overexpression of this mutant, but not of wild type Yih1, leads to a phenotype similar to that of YIH1 deletion, supporting the view that Yih1 is involved through Cdc28 in the regulation of the cell cycle. We further show that IMPACT, the mammalian homologue of Yih1, interacts with CDK1, the mammalian counterpart of Cdc28, indicating that the involvement with the cell cycle is conserved. Together, these data provide insights into the cellular function of Yih1/IMPACT, and provide the basis for future studies on the role of this protein in the cell cycle.
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Affiliation(s)
- Richard C. Silva
- Department of Microbiology, Immunology and Parasitology, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Martina Dautel
- Institute of Natural and Mathematical Sciences, Massey University, Auckland, New Zealand
| | - Bruno M. Di Genova
- Department of Microbiology, Immunology and Parasitology, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - David C. Amberg
- Department of Biochemistry and Molecular Biology, Upstate Medical University, State University of New York, Syracuse, New York, United States of America
| | - Beatriz A. Castilho
- Department of Microbiology, Immunology and Parasitology, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Evelyn Sattlegger
- Institute of Natural and Mathematical Sciences, Massey University, Auckland, New Zealand
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Tada H, Orii H. Dynamic intracellular localization of Dazl protein during Xenopus germline development. Histochem Cell Biol 2015; 144:157-66. [DOI: 10.1007/s00418-015-1323-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/08/2015] [Indexed: 12/13/2022]
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Polymenis M, Aramayo R. Translate to divide: сontrol of the cell cycle by protein synthesis. MICROBIAL CELL 2015; 2:94-104. [PMID: 28357283 PMCID: PMC5348972 DOI: 10.15698/mic2015.04.198] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Protein synthesis underpins much of cell growth and, consequently, cell multiplication. Understanding how proliferating cells commit and progress into the cell cycle requires knowing not only which proteins need to be synthesized, but also what determines their rate of synthesis during cell division.
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Affiliation(s)
- Michael Polymenis
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, USA
| | - Rodolfo Aramayo
- Department of Biology, Texas A&M University, College Station, TX 77843, USA
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45
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Guerrero S, Batisse J, Libre C, Bernacchi S, Marquet R, Paillart JC. HIV-1 replication and the cellular eukaryotic translation apparatus. Viruses 2015; 7:199-218. [PMID: 25606970 PMCID: PMC4306834 DOI: 10.3390/v7010199] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Accepted: 01/12/2015] [Indexed: 12/13/2022] Open
Abstract
Eukaryotic translation is a complex process composed of three main steps: initiation, elongation, and termination. During infections by RNA- and DNA-viruses, the eukaryotic translation machinery is used to assure optimal viral protein synthesis. Human immunodeficiency virus type I (HIV-1) uses several non-canonical pathways to translate its own proteins, such as leaky scanning, frameshifting, shunt, and cap-independent mechanisms. Moreover, HIV-1 modulates the host translation machinery by targeting key translation factors and overcomes different cellular obstacles that affect protein translation. In this review, we describe how HIV-1 proteins target several components of the eukaryotic translation machinery, which consequently improves viral translation and replication.
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Affiliation(s)
- Santiago Guerrero
- Architecture et Réactivité de l'ARN, CNRS, Université de Strasbourg, Institut de Biologie Moléculaire et Cellulaire, 15 rue René Descartes, 67084 Strasbourg cedex, France.
| | - Julien Batisse
- Architecture et Réactivité de l'ARN, CNRS, Université de Strasbourg, Institut de Biologie Moléculaire et Cellulaire, 15 rue René Descartes, 67084 Strasbourg cedex, France.
| | - Camille Libre
- Architecture et Réactivité de l'ARN, CNRS, Université de Strasbourg, Institut de Biologie Moléculaire et Cellulaire, 15 rue René Descartes, 67084 Strasbourg cedex, France.
| | - Serena Bernacchi
- Architecture et Réactivité de l'ARN, CNRS, Université de Strasbourg, Institut de Biologie Moléculaire et Cellulaire, 15 rue René Descartes, 67084 Strasbourg cedex, France.
| | - Roland Marquet
- Architecture et Réactivité de l'ARN, CNRS, Université de Strasbourg, Institut de Biologie Moléculaire et Cellulaire, 15 rue René Descartes, 67084 Strasbourg cedex, France.
| | - Jean-Christophe Paillart
- Architecture et Réactivité de l'ARN, CNRS, Université de Strasbourg, Institut de Biologie Moléculaire et Cellulaire, 15 rue René Descartes, 67084 Strasbourg cedex, France.
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Abstract
The Drosophila melanogaster ovary has served as a popular and successful model for understanding a wide range of biological processes: stem cell function, germ cell development, meiosis, cell migration, morphogenesis, cell death, intercellular signaling, mRNA localization, and translational control. This review provides a brief introduction to Drosophila oogenesis, along with a survey of its diverse biological topics and the advanced genetic tools that continue to make this a popular developmental model system.
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47
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Nath S, Ghatak D, Das P, Roychoudhury S. Transcriptional control of mitosis: deregulation and cancer. Front Endocrinol (Lausanne) 2015; 6:60. [PMID: 25999914 PMCID: PMC4419714 DOI: 10.3389/fendo.2015.00060] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Accepted: 04/08/2015] [Indexed: 12/22/2022] Open
Abstract
Research over the past few decades has well established the molecular functioning of mitosis. Deregulation of these functions has also been attributed to the generation of aneuploidy in different tumor types. Numerous studies have given insight into the regulation of mitosis by cell cycle specific proteins. Optimum abundance of these proteins is pivotal to timely execution of mitosis. Aberrant expressions of these mitotic proteins have been reported in different cancer types. Several post-transcriptional mechanisms and their interplay have subsequently been identified that control the level of mitotic proteins. However, to date, infrequent incidences of cancer-associated mutations have been reported for the genes expressing these proteins. Therefore, altered expression of these mitotic regulators in tumor samples can largely be attributed to transcriptional deregulation. This review discusses the biology of transcriptional control for mitosis and evaluates its role in the generation of aneuploidy and tumorigenesis.
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Affiliation(s)
- Somsubhra Nath
- Cancer Biology and Inflammatory Disorder Division, CSIR-Indian Institute of Chemical Biology, Kolkata, India
- Present address: Somsubhra Nath, Genetics, Cell Biology and Anatomy Division, University of Nebraska Medical Center, Omaha, NE, USA
| | - Dishari Ghatak
- Cancer Biology and Inflammatory Disorder Division, CSIR-Indian Institute of Chemical Biology, Kolkata, India
| | - Pijush Das
- Cancer Biology and Inflammatory Disorder Division, CSIR-Indian Institute of Chemical Biology, Kolkata, India
| | - Susanta Roychoudhury
- Cancer Biology and Inflammatory Disorder Division, CSIR-Indian Institute of Chemical Biology, Kolkata, India
- *Correspondence: Susanta Roychoudhury, Cancer Biology and Inflammatory Disorder Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Kolkata 700 032, India, ;
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Holmes M, Itaas V, Ananvoranich S. Sustained translational repression of lactate dehydrogenase 1 inToxoplasma gondiibradyzoites is conferred by a small regulatory RNA hairpin. FEBS J 2014; 281:5077-91. [DOI: 10.1111/febs.13048] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Revised: 09/04/2014] [Accepted: 09/09/2014] [Indexed: 12/24/2022]
Affiliation(s)
- Michael Holmes
- Department of Chemistry and Biochemistry; University of Windsor; Canada
| | - Vaunell Itaas
- Department of Chemistry and Biochemistry; University of Windsor; Canada
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Weng KA, Jeffreys CA, Bickel SE. Rejuvenation of meiotic cohesion in oocytes during prophase I is required for chiasma maintenance and accurate chromosome segregation. PLoS Genet 2014; 10:e1004607. [PMID: 25211017 PMCID: PMC4161318 DOI: 10.1371/journal.pgen.1004607] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Accepted: 07/14/2014] [Indexed: 11/19/2022] Open
Abstract
Chromosome segregation errors in human oocytes are the leading cause of birth defects, and the risk of aneuploid pregnancy increases dramatically as women age. Accurate segregation demands that sister chromatid cohesion remain intact for decades in human oocytes, and gradual loss of the original cohesive linkages established in fetal oocytes is proposed to be a major cause of age-dependent segregation errors. Here we demonstrate that maintenance of meiotic cohesion in Drosophila oocytes during prophase I requires an active rejuvenation program, and provide mechanistic insight into the molecular events that underlie rejuvenation. Gal4/UAS inducible knockdown of the cohesion establishment factor Eco after meiotic S phase, but before oocyte maturation, causes premature loss of meiotic cohesion, resulting in destabilization of chiasmata and subsequent missegregation of recombinant homologs. Reduction of individual cohesin subunits or the cohesin loader Nipped B during prophase I leads to similar defects. These data indicate that loading of newly synthesized replacement cohesin rings by Nipped B and establishment of new cohesive linkages by the acetyltransferase Eco must occur during prophase I to maintain cohesion in oocytes. Moreover, we show that rejuvenation of meiotic cohesion does not depend on the programmed induction of meiotic double strand breaks that occurs during early prophase I, and is therefore mechanistically distinct from the DNA damage cohesion re-establishment pathway identified in G2 vegetative yeast cells. Our work provides the first evidence that new cohesive linkages are established in Drosophila oocytes after meiotic S phase, and that these are required for accurate chromosome segregation. If such a pathway also operates in human oocytes, meiotic cohesion defects may become pronounced in a woman's thirties, not because the original cohesive linkages finally give out, but because the rejuvenation program can no longer supply new cohesive linkages at the same rate at which they are lost.
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Affiliation(s)
- Katherine A. Weng
- Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire, United States of America
| | - Charlotte A. Jeffreys
- Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire, United States of America
| | - Sharon E. Bickel
- Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire, United States of America
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Rajesh K, Papadakis AI, Kazimierczak U, Peidis P, Wang S, Ferbeyre G, Kaufman RJ, Koromilas AE. eIF2α phosphorylation bypasses premature senescence caused by oxidative stress and pro-oxidant antitumor therapies. Aging (Albany NY) 2013; 5:884-901. [PMID: 24334569 PMCID: PMC3883705 DOI: 10.18632/aging.100620] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Abstract
Eukaryotic cells respond to various forms of stress by blocking mRNA translation initiation via the phosphorylation of the alpha (α) subunit of eIF2 at serine 51 (S51) (eIFαP). An important role of eIF2αP is the regulation of redox homeostasis and adaptation of cells to oxidative stress. Herein, we demonstrate that eIF2αP guards cells from intracellular reactive oxygen species (ROS) via the inhibition of senescence. Specifically, genetic inactivation of either eIF2αP or eIF2α kinase PERK in primary mouse or human fibroblasts leads to proliferative defects associated with increased DNA damage, G2/M accumulation and induction of premature senescence. Impaired proliferation of either PERK or eIF2αP-deficient primary cells is caused by increased ROS and restored by anti-oxidant treatment. Contrary to primary cells, impaired eIF2αP in immortalized mouse fibroblasts or human tumor cells provides tolerance to elevated intracellular ROS levels. However, eIF2αP-deficient human tumor cells are highly susceptible to extrinsic ROS generated by the pro-oxidant drug doxorubicin by undergoing premature senescence. Our work demonstrates that eIF2αP determines cell destiny through its capacity to control senescence in response to oxidative stress. Also, inhibition of eIF2αP may be a suitable means to increase the anti-tumor effects of pro-oxidant drugs through the induction of senescence.
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Affiliation(s)
- Kamindla Rajesh
- Lady Davis Institute for Medical Research, McGill University, Sir Mortimer B. Davis-Jewish General Hospital, Montreal, Quebec H3T 1E2, Canada
| | - Andreas I. Papadakis
- Lady Davis Institute for Medical Research, McGill University, Sir Mortimer B. Davis-Jewish General Hospital, Montreal, Quebec H3T 1E2, Canada
| | - Urszula Kazimierczak
- Lady Davis Institute for Medical Research, McGill University, Sir Mortimer B. Davis-Jewish General Hospital, Montreal, Quebec H3T 1E2, Canada
- Department of Cancer Immunology, Chair of Medical Biotechnology, Poznan University of Medical Sciences, Poland
| | - Philippos Peidis
- Lady Davis Institute for Medical Research, McGill University, Sir Mortimer B. Davis-Jewish General Hospital, Montreal, Quebec H3T 1E2, Canada
| | - Shuo Wang
- Lady Davis Institute for Medical Research, McGill University, Sir Mortimer B. Davis-Jewish General Hospital, Montreal, Quebec H3T 1E2, Canada
| | - Gerardo Ferbeyre
- Département de Biochimie, Université de Montréal; Montréal, Québec H3C 3J7, Canada
| | - Randal J. Kaufman
- Center for Neuroscience, Aging and Stem Cell Research, Sanford Burnham Medical Research Institute, La Jolla, CA 92037, USA
| | - Antonis E. Koromilas
- Lady Davis Institute for Medical Research, McGill University, Sir Mortimer B. Davis-Jewish General Hospital, Montreal, Quebec H3T 1E2, Canada
- Department of Oncology, Faculty of Medicine, McGill University, Montreal, Quebec H2W 1S6, Canada
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