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Fiorentino G, Merico V, Zanoni M, Comincini S, Sproviero D, Garofalo M, Gagliardi S, Cereda C, Lin CJ, Innocenti F, Taggi M, Vaiarelli A, Ubaldi FM, Rienzi L, Cimadomo D, Garagna S, Zuccotti M. Extracellular vesicles secreted by cumulus cells contain microRNAs that are potential regulatory factors of mouse oocyte developmental competence. Mol Hum Reprod 2024; 30:gaae019. [PMID: 38745364 DOI: 10.1093/molehr/gaae019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 04/23/2024] [Indexed: 05/16/2024] Open
Abstract
The role of cumulus cells (CCs) in the acquisition of oocyte developmental competence is not yet fully understood. In a previous study, we matured cumulus-denuded fully-grown mouse oocytes to metaphase II (MII) on a feeder layer of CCs (FL-CCs) isolated from developmentally competent (FL-SN-CCs) or incompetent (FL-NSN-CCs) SN (surrounded nucleolus) or NSN (not surrounding nucleolus) oocytes, respectively. We observed that oocytes cultured on the former could develop into blastocysts, while those matured on the latter arrested at the 2-cell stage. To investigate the CC factors contributing to oocyte developmental competence, here we focused on the CCs' release into the medium of extracellular vesicles (EVs) and on their miRNA content. We found that, during the 15-h transition to MII, both FL-SN-CCs and FL-NSN-CCs release EVs that can be detected, by confocal microscopy, inside the zona pellucida (ZP) or the ooplasm. The majority of EVs are <200 nm in size, which is compatible with their ability to cross the ZP. Next-generation sequencing of the miRNome of FL-SN-CC versus FL-NSN-CC EVs highlighted 74 differentially expressed miRNAs, with 43 up- and 31 down-regulated. Although most of these miRNAs do not have known roles in the ovary, in silico functional analysis showed that seven of these miRNAs regulate 71 target genes with specific roles in meiosis resumption (N = 24), follicle growth (N = 23), fertilization (N = 1), and the acquisition of oocyte developmental competence (N = 23). Overall, our results indicate CC EVs as emerging candidates of the CC-to-oocyte communication axis and uncover a group of miRNAs as potential regulatory factors.
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Affiliation(s)
- Giulia Fiorentino
- Laboratory of Biology and Biotechnology of Reproduction, Department of Biology and Biotechnology 'Lazzaro Spallanzani', University of Pavia, Pavia, Italy
| | - Valeria Merico
- Laboratory of Biology and Biotechnology of Reproduction, Department of Biology and Biotechnology 'Lazzaro Spallanzani', University of Pavia, Pavia, Italy
| | - Mario Zanoni
- Laboratory of Biology and Biotechnology of Reproduction, Department of Biology and Biotechnology 'Lazzaro Spallanzani', University of Pavia, Pavia, Italy
| | - Sergio Comincini
- Functional Genomics Laboratory, Department of Biology and Biotechnology 'Lazzaro Spallanzani', University of Pavia, Pavia, Italy
| | - Daisy Sproviero
- IFOM, IFOM-The FIRC Institute of Molecular Oncology, Milan, Italy
| | - Maria Garofalo
- Molecular Biology and Transcriptomics Unit, IRCCS Mondino Foundation, Pavia, Italy
| | - Stella Gagliardi
- Molecular Biology and Transcriptomics Unit, IRCCS Mondino Foundation, Pavia, Italy
| | - Cristina Cereda
- Department of Pediatrics, Center of Functional Genomics and Rare Diseases, Buzzi Children's Hospital, Milan, Italy
| | - Chih-Jen Lin
- Centre for Reproductive Health, Institute for Regeneration and Repair, University of Edinburgh, Edinburgh, UK
| | - Federica Innocenti
- IVIRMA Global Research Alliance, GENERA, Clinica Valle Giulia, Rome, Italy
| | - Marilena Taggi
- IVIRMA Global Research Alliance, GENERA, Clinica Valle Giulia, Rome, Italy
| | - Alberto Vaiarelli
- IVIRMA Global Research Alliance, GENERA, Clinica Valle Giulia, Rome, Italy
| | | | - Laura Rienzi
- IVIRMA Global Research Alliance, GENERA, Clinica Valle Giulia, Rome, Italy
- Department of Biomolecular Sciences, University of Urbino "Carlo Bo", Urbino, Italy
| | - Danilo Cimadomo
- IVIRMA Global Research Alliance, GENERA, Clinica Valle Giulia, Rome, Italy
| | - Silvia Garagna
- Laboratory of Biology and Biotechnology of Reproduction, Department of Biology and Biotechnology 'Lazzaro Spallanzani', University of Pavia, Pavia, Italy
| | - Maurizio Zuccotti
- Laboratory of Biology and Biotechnology of Reproduction, Department of Biology and Biotechnology 'Lazzaro Spallanzani', University of Pavia, Pavia, Italy
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Tan K, Wilkinson MF. Regulation of both transcription and RNA turnover contribute to germline specification. Nucleic Acids Res 2022; 50:7310-7325. [PMID: 35776114 PMCID: PMC9303369 DOI: 10.1093/nar/gkac542] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 05/29/2022] [Accepted: 06/29/2022] [Indexed: 12/25/2022] Open
Abstract
The nuanced mechanisms driving primordial germ cells (PGC) specification remain incompletely understood since genome-wide transcriptional regulation in developing PGCs has previously only been defined indirectly. Here, using SLAMseq analysis, we determined genome-wide transcription rates during the differentiation of embryonic stem cells (ESCs) to form epiblast-like (EpiLC) cells and ultimately PGC-like cells (PGCLCs). This revealed thousands of genes undergoing bursts of transcriptional induction and rapid shut-off not detectable by RNAseq analysis. Our SLAMseq datasets also allowed us to infer RNA turnover rates, which revealed thousands of mRNAs stabilized and destabilized during PGCLC specification. mRNAs tend to be unstable in ESCs and then are progressively stabilized as they differentiate. For some classes of genes, mRNA turnover regulation collaborates with transcriptional regulation, but these processes oppose each other in a surprisingly high frequency of genes. To test whether regulated mRNA turnover has a physiological role in PGC development, we examined three genes that we found were regulated by RNA turnover: Sox2, Klf2 and Ccne1. Circumvention of their regulated RNA turnover severely impaired the ESC-to-EpiLC and EpiLC-to-PGCLC transitions. Our study demonstrates the functional importance of regulated RNA stability in germline development and provides a roadmap of transcriptional and post-transcriptional regulation during germline specification.
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Affiliation(s)
- Kun Tan
- Department of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine, University of California San Diego, La Jolla, CA 92093, USA
| | - Miles F Wilkinson
- Department of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine, University of California San Diego, La Jolla, CA 92093, USA
- Institute of Genomic Medicine (IGM), University of California San Diego, La Jolla, CA 92093, USA
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Kontio JAJ, Pyhäjärvi T, Sillanpää MJ. Model guided trait-specific co-expression network estimation as a new perspective for identifying molecular interactions and pathways. PLoS Comput Biol 2021; 17:e1008960. [PMID: 33939702 PMCID: PMC8118548 DOI: 10.1371/journal.pcbi.1008960] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 05/13/2021] [Accepted: 04/13/2021] [Indexed: 11/19/2022] Open
Abstract
A wide variety of 1) parametric regression models and 2) co-expression networks have been developed for finding gene-by-gene interactions underlying complex traits from expression data. While both methodological schemes have their own well-known benefits, little is known about their synergistic potential. Our study introduces their methodological fusion that cross-exploits the strengths of individual approaches via a built-in information-sharing mechanism. This fusion is theoretically based on certain trait-conditioned dependency patterns between two genes depending on their role in the underlying parametric model. Resulting trait-specific co-expression network estimation method 1) serves to enhance the interpretation of biological networks in a parametric sense, and 2) exploits the underlying parametric model itself in the estimation process. To also account for the substantial amount of intrinsic noise and collinearities, often entailed by expression data, a tailored co-expression measure is introduced along with this framework to alleviate related computational problems. A remarkable advance over the reference methods in simulated scenarios substantiate the method's high-efficiency. As proof-of-concept, this synergistic approach is successfully applied in survival analysis, with acute myeloid leukemia data, further highlighting the framework's versatility and broad practical relevance.
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Affiliation(s)
- Juho A. J. Kontio
- Research Unit of Mathematical Sciences, University of Oulu, Oulu, Finland
| | - Tanja Pyhäjärvi
- Department of Ecology and Genetics, University of Oulu, Oulu, Finland
- Department of Forest Sciences, University of Helsinki, Helsinki, Finland
| | - Mikko J. Sillanpää
- Research Unit of Mathematical Sciences, University of Oulu, Oulu, Finland
- * E-mail:
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Ter Huurne M, Stunnenberg HG. G1-phase progression in pluripotent stem cells. Cell Mol Life Sci 2021; 78:4507-4519. [PMID: 33884444 PMCID: PMC8195903 DOI: 10.1007/s00018-021-03797-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 01/19/2021] [Accepted: 02/19/2021] [Indexed: 11/10/2022]
Abstract
During early embryonic development both the rapid increase in cell number and the expression of genes that control developmental decisions are tightly regulated. Accumulating evidence has indicated that these two seemingly independent processes are mechanistically intertwined. The picture that emerges from studies on the cell cycle of embryonic stem cells is one in which proteins that promote cell cycle progression prevent differentiation and vice versa. Here, we review which transcription factors and signalling pathways play a role in both maintenance of pluripotency as well as cell cycle progression. We will not only describe the mechanism behind their function but also discuss the role of these regulators in different states of mouse pluripotency. Finally, we elaborate on how canonical cell cycle regulators impact on the molecular networks that control the maintenance of pluripotency and lineage specification.
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Affiliation(s)
- Menno Ter Huurne
- Department of Molecular Biology, Faculty of Science, Radboud University, 6525GA, Nijmegen, The Netherlands
- Murdoch Children's Research Institute, Royal Children's Hospital, Flemington Rd, Parkville, Melbourne, VIC, 3052, Australia
| | - Hendrik G Stunnenberg
- Department of Molecular Biology, Faculty of Science, Radboud University, 6525GA, Nijmegen, The Netherlands.
- Princess Maxima Centre for Pediatric Oncology, Heidelberglaan 25, 3584 CS, Utrecht, The Netherlands.
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Identification of positive and negative regulators in the stepwise developmental progression towards infectivity in Trypanosoma brucei. Sci Rep 2021; 11:5755. [PMID: 33707699 PMCID: PMC7952579 DOI: 10.1038/s41598-021-85225-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 02/25/2021] [Indexed: 11/17/2022] Open
Abstract
Trypanosoma brucei is a protozoan parasite that causes important human and livestock diseases in sub-Saharan Africa. By overexpressing a single RNA-binding protein, RBP6, in non-infectious procyclics trypanosomes, we previously recapitulated in vitro the events occurring in the tsetse fly vector, namely the development of epimastigotes and infectious, quiescent metacyclic parasites. To identify genes involved in this developmental progression, we individually targeted 86 transcripts by RNAi in the RBP6 overexpression cell line and assessed the loss-of-function phenotypes on repositioning the kinetoplast, an organelle that contains the mitochondrial genome, the expression of BARP or brucei alanine rich protein, a marker for epimastigotes, and metacyclic variant surface glycoprotein. This screen identified 22 genes that positively or negatively regulate the stepwise progression towards infectivity at different stages. Two previously uncharacterized putative nucleic acid binding proteins emerged as potent regulators, namely the cold shock domain-containing proteins CSD1 and CSD2. RNA-Seq data from a selected group of cell lines further revealed that the components of gene expression regulatory networks identified in this study affected the abundance of a subset of transcripts in very similar fashion. Finally, our data suggest a considerable overlap between the genes that regulate the formation of stumpy bloodstream form trypanosomes and the genes that govern the development of metacyclic form parasites.
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Tocci A. The unknown human trophectoderm: implication for biopsy at the blastocyst stage. J Assist Reprod Genet 2020; 37:2699-2711. [PMID: 32892265 DOI: 10.1007/s10815-020-01925-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 08/11/2020] [Indexed: 11/30/2022] Open
Abstract
Trophectoderm biopsy is increasingly performed for pre-implantation genetic testing of aneuploidies and considered a safe procedure on short-term clinical outcome, without strong assessment of long-term consequences. Poor biological information on human trophectoderm is available due to ethical restrictions. Therefore, most studies have been conducted in vitro (choriocarcinoma cell lines, embryonic and pluripotent stem cells) and on murine models that nevertheless poorly reflect the human counterpart. Polarization, compaction, and blastomere differentiation (e.g., the basis to ascertain trophectoderm origin) are poorly known in humans. In addition, the trophectoderm function is poorly known from a biological point of view, although a panoply of questionable and controversial microarray studies suggest that important genes overexpressed in trophectoderm are involved in pluripotency, metabolism, cell cycle, endocrine function, and implantation. The intercellular communication system between the trophectoderm cells and the inner cell mass, modulated by cell junctions and filopodia in the murine model, is obscure in humans. For the purpose of this paper, data mainly on primary cells from human and murine embryos has been reviewed. This review suggests that the trophectoderm origin and functions have been insufficiently ascertained in humans so far. Therefore, trophectoderm biopsy should be considered an experimental procedure to be undertaken only under approved rigorous experimental protocols in academic contexts.
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Affiliation(s)
- Angelo Tocci
- Reproductive Medicine Unit, Gruppo Donnamed, Via Giuseppe Silla 12, Rome, Italy.
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Hu K. On Mammalian Totipotency: What Is the Molecular Underpinning for the Totipotency of Zygote? Stem Cells Dev 2020; 28:897-906. [PMID: 31122174 PMCID: PMC6648208 DOI: 10.1089/scd.2019.0057] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The mammalian zygote is described as a totipotent cell in the literature, but this characterization is elusive ignoring the molecular underpinnings. Totipotency can connote genetic totipotency, epigenetic totipotency, or the reprogramming capacity of a cell to epigenetic totipotency. Here, the implications of these concepts are discussed in the context of the properties of the zygote. Although genetically totipotent as any diploid somatic cell is, a zygote seems not totipotent transcriptionally, epigenetically, or functionally. Yet, a zygote may retain most of the key factors from its parental oocyte to reprogram an implanted differentiated genome or the zygote genome toward totipotency. This totipotent reprogramming process may extend to blastomeres in the two-cell-stage embryo. Thus, a revised alternative model of mammalian cellular totipotency is proposed, in which an epigenetically totipotent cell exists after the major embryonic genome activation and before the separation of the first two embryonic lineages.
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Affiliation(s)
- Kejin Hu
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, Alabama
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Patra SK. Roles of OCT4 in pathways of embryonic development and cancer progression. Mech Ageing Dev 2020; 189:111286. [PMID: 32531293 DOI: 10.1016/j.mad.2020.111286] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 04/08/2020] [Accepted: 06/06/2020] [Indexed: 12/11/2022]
Abstract
Somatic cells may be reprogrammed to pluripotent state by ectopic expression of certain transcription factors; namely, OCT4, SOX2, KLF4 and c-MYC. However, the molecular and cellular mechanisms are not adequately understood, especially for human embryonic development. Studies during the last five years implicated importance of OCT4 in human zygotic genome activation (ZGA), patterns of OCT4 protein folding and role of specialized sequences in binding to DNA for modulation of gene expression during development. Epigenetic modulation of OCT4 gene and post translational modifications of OCT4 protein activity in the context of multiple cancers are important issues. A consensus is emerging that chromatin organization and epigenetic landscape play crucial roles for the interactions of transcription factors, including OCT4 with the promoters and/or regulatory sequences of genes associated with human embryonic development (ZGA through lineage specification) and that when the epigenome niche is deregulated OCT4 helps in cancer progression, and how OCT4 silencing in somatic cells of adult organisms may impact ageing.
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Affiliation(s)
- Samir Kumar Patra
- Epigenetics and Cancer Research Laboratory, Biochemistry and Molecular Biology Group, Department of Life Science, National Institute of Technology, Rourkela, Odisha, 769008, India.
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Rodríguez Varela MS, Mucci S, Videla Richardson GA, Morris Hanon O, Furmento VA, Miriuka SG, Sevlever GE, Scassa ME, Romorini L. Regulation of cyclin E1 expression in human pluripotent stem cells and derived neural progeny. Cell Cycle 2018; 17:1721-1744. [PMID: 29995582 DOI: 10.1080/15384101.2018.1496740] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Human pluripotent stem cells (hPSCs), including embryonic and induced pluripotent stem cells (hESCs and hiPSCs) show unique cell cycle characteristics, such as a short doubling time due to an abbreviated G1 phase. Whether or not the core cell cycle machinery directly regulates the stemness and/or the differentiation potential of hPSCs remains to be determined. To date, several scenarios describing the atypical cell cycle of hPSCs have been suggested, and therefore there is still controversy over how cyclins, master regulators of the cell cycle, are expressed and regulated. Furthermore, the cell cycle profile and the expression pattern of major cyclins in hESCs-derived neuroprogenitors (NP) have not been studied yet. Therefore, herein we characterized the expression pattern of major cyclins in hPSCs and NP. We determined that all studied cyclins mRNA expression levels fluctuate along cell cycle. Particularly, after a thorough analysis of synchronized cell populations, we observed that cyclin E1 mRNA levels increased sharply in G1/S concomitantly with cyclin E1 protein accumulation in hPSCs and NP. Additionally, we demonstrated that cyclin E1 mRNA expression levels involves the activation of MEK/ERK pathway and the transcription factors c-Myc and E2Fs in hPSCs. Lastly, our results reveal that proteasome mediates the marked down-regulation (degradation) of cyclin E1 protein observed in G2/M by a mechanism that requires a functional CDK2 but not GSK3β activity. ABBREVIATIONS hPSCs: human pluripotent stem cells; hESCs: human embryonic stem cells; hiPSCs: human induced pluripotent stem cells; NP: neuroprogenitors; HF: human foreskin fibroblasts; MEFs: mouse embryonic fibroblasts; iMEFs: irradiated mouse embryonic fibroblasts; CDKs: cyclindependent kinases; CKIs: CDK inhibitors; CNS: central nervous system; Oct-4: Octamer-4; EB: embryoid body; AFP: Alpha-fetoprotein; cTnT: Cardiac Troponin T; MAP-2: microtubule-associated protein; TUJ-1: neuron-specific class III β-tubulin; bFGF: basic fibroblastic growth factor; PI3K: Phosphoinositide 3-kinase; KSR: knock out serum replacement; CM: iMEF conditioned medium; E8: Essential E8 medium.
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Affiliation(s)
- María Soledad Rodríguez Varela
- a Laboratorios de Investigación Aplicada en Neurociencias (LIAN-CONICET) , Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia (FLENI) , Belén de Escobar , Provincia de Buenos Aires , Argentina
| | - Sofía Mucci
- a Laboratorios de Investigación Aplicada en Neurociencias (LIAN-CONICET) , Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia (FLENI) , Belén de Escobar , Provincia de Buenos Aires , Argentina
| | - Guillermo Agustín Videla Richardson
- a Laboratorios de Investigación Aplicada en Neurociencias (LIAN-CONICET) , Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia (FLENI) , Belén de Escobar , Provincia de Buenos Aires , Argentina
| | - Olivia Morris Hanon
- a Laboratorios de Investigación Aplicada en Neurociencias (LIAN-CONICET) , Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia (FLENI) , Belén de Escobar , Provincia de Buenos Aires , Argentina
| | - Verónica Alejandra Furmento
- a Laboratorios de Investigación Aplicada en Neurociencias (LIAN-CONICET) , Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia (FLENI) , Belén de Escobar , Provincia de Buenos Aires , Argentina
| | - Santiago Gabriel Miriuka
- a Laboratorios de Investigación Aplicada en Neurociencias (LIAN-CONICET) , Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia (FLENI) , Belén de Escobar , Provincia de Buenos Aires , Argentina
| | - Gustavo Emilio Sevlever
- a Laboratorios de Investigación Aplicada en Neurociencias (LIAN-CONICET) , Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia (FLENI) , Belén de Escobar , Provincia de Buenos Aires , Argentina
| | - María Elida Scassa
- a Laboratorios de Investigación Aplicada en Neurociencias (LIAN-CONICET) , Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia (FLENI) , Belén de Escobar , Provincia de Buenos Aires , Argentina
| | - Leonardo Romorini
- a Laboratorios de Investigación Aplicada en Neurociencias (LIAN-CONICET) , Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia (FLENI) , Belén de Escobar , Provincia de Buenos Aires , Argentina
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Zaveri L, Dhawan J. Cycling to Meet Fate: Connecting Pluripotency to the Cell Cycle. Front Cell Dev Biol 2018; 6:57. [PMID: 29974052 PMCID: PMC6020794 DOI: 10.3389/fcell.2018.00057] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2018] [Accepted: 05/14/2018] [Indexed: 01/26/2023] Open
Abstract
Pluripotent stem cells are characterized by their high proliferative rates, their ability to self-renew and their potential to differentiate to all the three germ layers. This rapid proliferation is brought about by a highly modified cell cycle that allows the cells to quickly shuttle from DNA synthesis to cell division, by reducing the time spent in the intervening gap phases. Many key regulators that define the somatic cell cycle are either absent or exhibit altered behavior, allowing the pluripotent cell to bypass cell cycle checkpoints typical of somatic cells. Experimental analysis of this modified stem cell cycle has been challenging due to the strong link between rapid proliferation and pluripotency, since perturbations to the cell cycle or pluripotency factors result in differentiation. Despite these hurdles, our understanding of this unique cell cycle has greatly improved over the past decade, in part because of the availability of new technologies that permit the analysis of single cells in heterogeneous populations. This review aims to highlight some of the recent discoveries in this area with a special emphasis on different states of pluripotency. We also discuss the highly interlinked network that connects pluripotency factors and key cell cycle genes and review evidence for how this interdependency may promote the rapid cell cycle. This issue gains translational importance since disruptions in stem cell proliferation and differentiation can impact disorders at opposite ends of a spectrum, from cancer to degenerative disease.
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Affiliation(s)
- Lamuk Zaveri
- Institute for Stem Cell Biology and Regenerative Medicine, Bangalore, India.,CSIR - Centre for Cellular and Molecular Biology, Hyderabad, India.,Manipal Academy of Higher Education, Manipal, India
| | - Jyotsna Dhawan
- Institute for Stem Cell Biology and Regenerative Medicine, Bangalore, India.,CSIR - Centre for Cellular and Molecular Biology, Hyderabad, India
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11
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Zang Y, Dong M, Zhang K, Tian W, Wang Y, Xue F. Bioinformatics analysis of key differentially expressed genes in well and poorly differentiated endometrial carcinoma. Mol Med Rep 2018; 18:467-476. [PMID: 29749513 DOI: 10.3892/mmr.2018.8969] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Accepted: 04/26/2018] [Indexed: 11/06/2022] Open
Abstract
Endometrial carcinoma (EC) is one of the most common gynecological malignancies. The malignant degree increases between grade (G)1 and G3, and EC of G3 usually presents a high recurrence rate and poor prognosis. Therefore, the present study aimed to examine the principal genes associated with the degree of differentiation in EC. The microarrays GSE17025, GSE24537 and GSE35784, representing data of Type I EC samples of G1 and G3, were downloaded from the Gene Expression Omnibus. The differentially expressed genes (DEGs) and differentially expressed micro (mi)RNAs (DEMs) were identified, followed by functional enrichment analyses and interaction network construction. In total, 83 upregulated and 130 downregulated DEGs with the same expression trends in two mRNA datasets were screened. The upregulated DEGs were primarily enriched in 'mitotic cell cycle process', 'cell cycle process' and 'mitotic cell cycle'; while the downregulated DEGs were enriched in 'cellular component assembly involved in morphogenesis', 'cell projection organization' and 'microtubule‑based movement'. From the protein‑protein interaction network, DNA topoisomerase IIα, kinesin family member 11, cyclin B1 and BUB1 mitotic checkpoint serine/threonine were identified as foremost hub genes. One module was extracted and involved in 'mitotic cell cycle process' and 'cell cycle process'. Based on the analysis of DEMs and the miRNA‑target regulatory network, miRNA‑9 may be the most important upregulated DEM, and the DEGs forkhead box P1 and cyclin E1 may serve vital roles in the differentiation of EC. In conclusion, principal genes were identified that may be determinants of the carcinogenesis of poorly differentiated EC, which may facilitate the examination of potential molecular mechanisms. These genes may additionally help identify candidate biomarkers and novel therapeutic targets for poorly differentiated EC.
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Affiliation(s)
- Yuqin Zang
- Department of Gynecology and Obstetrics, Tianjin Medical University General Hospital, Tianjin 300052, P.R. China
| | - Mengting Dong
- Department of Gynecology and Obstetrics, Tianjin Medical University General Hospital, Tianjin 300052, P.R. China
| | - Kai Zhang
- Department of Gynecology and Obstetrics, Tianjin Medical University General Hospital, Tianjin 300052, P.R. China
| | - Wenyan Tian
- Department of Gynecology and Obstetrics, Tianjin Medical University General Hospital, Tianjin 300052, P.R. China
| | - Yingmei Wang
- Department of Gynecology and Obstetrics, Tianjin Medical University General Hospital, Tianjin 300052, P.R. China
| | - Fengxia Xue
- Department of Gynecology and Obstetrics, Tianjin Medical University General Hospital, Tianjin 300052, P.R. China
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Guo J, Shin KT, Cui XS. Analysis of Cyclin E1 Functions in Porcine Preimplantation Embryonic Development by Fluorescence Microscopy. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2017; 23:69-76. [PMID: 28162122 DOI: 10.1017/s1431927616012733] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Cyclin E1 (CCNE1) is a core component of cell cycle regulation that drives the transition into the S phase. CCNE1 plays critical roles in cell cycle, cell proliferation, and cellular functions. However, the function of CCNE1 in early embryonic development is limited. In the present study, the function and expression of Ccne1 in porcine early parthenotes were examined. Immunostaining experiments showed that CCNE1 localized in the nucleus, starting at the four-cell stage. Knockdown of Ccne1 by double-stranded RNA resulted in the failure of blastocyst formation and induced blastocyst apoptosis. Ccne1 depletion increased expression of the pro-apoptotic gene Bax, and decreased the expression of Oct4 and the rate of inner cell mass (ICM)/trophectoderm formation. The results indicated that CCNE1 affects blastocyst formation by inducing cell apoptosis and ICM formation during porcine embryonic development.
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Affiliation(s)
- Jing Guo
- Department of Animal Sciences,Chungbuk National University,Chungbuk,Cheongju 361-763,Republic of Korea
| | - Kyung-Tae Shin
- Department of Animal Sciences,Chungbuk National University,Chungbuk,Cheongju 361-763,Republic of Korea
| | - Xiang-Shun Cui
- Department of Animal Sciences,Chungbuk National University,Chungbuk,Cheongju 361-763,Republic of Korea
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