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Niharika, Ureka L, Roy A, Patra SK. Dissecting SOX2 expression and function reveals an association with multiple signaling pathways during embryonic development and in cancer progression. Biochim Biophys Acta Rev Cancer 2024; 1879:189136. [PMID: 38880162 DOI: 10.1016/j.bbcan.2024.189136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 06/03/2024] [Accepted: 06/10/2024] [Indexed: 06/18/2024]
Abstract
SRY (Sex Determining Region) box 2 (SOX2) is an essential transcription factor that plays crucial roles in activating genes involved in pre- and post-embryonic development, adult tissue homeostasis, and lineage specifications. SOX2 maintains the self-renewal property of stem cells and is involved in the generation of induced pluripotency stem cells. SOX2 protein contains a particular high-mobility group domain that enables SOX2 to achieve the capacity to participate in a broad variety of functions. The information about the involvement of SOX2 with gene regulatory elements, signaling networks, and microRNA is gradually emerging, and the higher expression of SOX2 is functionally relevant to various cancer types. SOX2 facilitates the oncogenic phenotype via cellular proliferation and enhancement of invasive tumor properties. Evidence are accumulating in favor of three dimensional (higher order) folding of chromatin and epigenetic control of the SOX2 gene by chromatin modifications, which implies that the expression level of SOX2 can be modulated by epigenetic regulatory mechanisms, specifically, via DNA methylation and histone H3 modification. In view of this, and to focus further insights into the roles SOX2 plays in physiological functions, involvement of SOX2 during development, precisely, the advances of our knowledge in pre- and post-embryonic development, and interactions of SOX2 in this scenario with various signaling pathways in tumor development and cancer progression, its potential as a therapeutic target against many cancers are summarized and discussed in this article.
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Affiliation(s)
- Niharika
- Epigenetics and Cancer Research Laboratory, Biochemistry and Molecular Biology Group, Department of Life Science, National Institute of Technology, Rourkela 769008, Odisha, India
| | - Lina Ureka
- Epigenetics and Cancer Research Laboratory, Biochemistry and Molecular Biology Group, Department of Life Science, National Institute of Technology, Rourkela 769008, Odisha, India
| | - Ankan Roy
- Epigenetics and Cancer Research Laboratory, Biochemistry and Molecular Biology Group, Department of Life Science, National Institute of Technology, Rourkela 769008, Odisha, India
| | - Samir Kumar Patra
- Epigenetics and Cancer Research Laboratory, Biochemistry and Molecular Biology Group, Department of Life Science, National Institute of Technology, Rourkela 769008, Odisha, India.
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2
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Navolić J, Moritz M, Voß H, Schlumbohm S, Schumann Y, Schlüter H, Neumann JE, Hahn J. Direct 3D Sampling of the Embryonic Mouse Head: Layer-wise Nanosecond Infrared Laser (NIRL) Ablation from Scalp to Cortex for Spatially Resolved Proteomics. Anal Chem 2023; 95:17220-17227. [PMID: 37956982 PMCID: PMC10688223 DOI: 10.1021/acs.analchem.3c02637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 10/06/2023] [Accepted: 10/12/2023] [Indexed: 11/21/2023]
Abstract
Common workflows in bottom-up proteomics require homogenization of tissue samples to gain access to the biomolecules within the cells. The homogenized tissue samples often contain many different cell types, thereby representing an average of the natural proteome composition, and rare cell types are not sufficiently represented. To overcome this problem, small-volume sampling and spatial resolution are needed to maintain a better representation of the sample composition and their proteome signatures. Using nanosecond infrared laser ablation, the region of interest can be targeted in a three-dimensional (3D) fashion, whereby the spatial information is maintained during the simultaneous process of sampling and homogenization. In this study, we ablated 40 μm thick consecutive layers directly from the scalp through the cortex of embryonic mouse heads and analyzed them by subsequent bottom-up proteomics. Extra- and intracranial ablated layers showed distinct proteome profiles comprising expected cell-specific proteins. Additionally, known cortex markers like SOX2, KI67, NESTIN, and MAP2 showed a layer-specific spatial protein abundance distribution. We propose potential new marker proteins for cortex layers, such as MTA1 and NMRAL1. The obtained data confirm that the new 3D tissue sampling and homogenization method is well suited for investigating the spatial proteome signature of tissue samples in a layerwise manner. Characterization of the proteome composition of embryonic skin and bone structures, meninges, and cortex lamination in situ enables a better understanding of molecular mechanisms of development during embryogenesis and disease pathogenesis.
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Affiliation(s)
- Jelena Navolić
- Research
Group Molecular Pathology in Neurooncology, Center for Molecular Neurobiology
(ZMNH), University Medical Center Hamburg−Eppendorf, Falkenried 94, 20251 Hamburg, Germany
| | - Manuela Moritz
- Section/Core
Facility Mass Spectrometry and Proteomics, Center for Diagnostics, University Medical Center Hamburg−Eppendorf, Martinistraße 52, 20251 Hamburg, Germany
| | - Hannah Voß
- Section/Core
Facility Mass Spectrometry and Proteomics, Center for Diagnostics, University Medical Center Hamburg−Eppendorf, Martinistraße 52, 20251 Hamburg, Germany
| | - Simon Schlumbohm
- High
Performance Computing, Helmut Schmidt University, Holstenhofweg 85, 22043 Hamburg, Germany
| | - Yannis Schumann
- High
Performance Computing, Helmut Schmidt University, Holstenhofweg 85, 22043 Hamburg, Germany
| | - Hartmut Schlüter
- Section/Core
Facility Mass Spectrometry and Proteomics, Center for Diagnostics, University Medical Center Hamburg−Eppendorf, Martinistraße 52, 20251 Hamburg, Germany
| | - Julia E. Neumann
- Research
Group Molecular Pathology in Neurooncology, Center for Molecular Neurobiology
(ZMNH), University Medical Center Hamburg−Eppendorf, Falkenried 94, 20251 Hamburg, Germany
- Institute
of Neuropathology, University Medical Center
Hamburg−Eppendorf, Martinistraße 52, 20251 Hamburg, Germany
| | - Jan Hahn
- Section/Core
Facility Mass Spectrometry and Proteomics, Center for Diagnostics, University Medical Center Hamburg−Eppendorf, Martinistraße 52, 20251 Hamburg, Germany
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3
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Dahab M, Ben-Dhaou C, Cherif-Feildel M, Moftah M, Hussein HK, Moyse E, Salam SA. Neural stem cells characterization in the vagal complex of adult ovine brain: A combined neurosphere assay/RTqPCR approach. Res Vet Sci 2023; 164:105025. [PMID: 37804666 DOI: 10.1016/j.rvsc.2023.105025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 09/18/2023] [Accepted: 09/19/2023] [Indexed: 10/09/2023]
Abstract
Neural stem cells are the effectors of adult neurogenesis, which occurs in discrete restricted areas of adult mammalian brain. In ovine species, like in rodents, in vivo incorporation of labeled DNA precursor led to characterize neurogenic proliferation in the subventricular zone and progeny migration and differentiation into the olfactory bulb. The present study addresses directly the existence of neural stem cells in the neurogenic niche of the vagal centre (area postrema) by in vitro neurosphere assay and RT-qPCR of specific markers on ex-vivo adult tissue explants, comparatively with the canonical neurogenic niche: the subventricular zone (SVZ) of the forebrain. Explants defined from the neuroanatomical patterns of in vivo BrdU incorporation yielded expandable and self-renewing spheres from both SVZ and AP. Within SVZ though, the density of sphere-forming cells was higher in ventral SVZ (SVZ-V) than in its latero-dorsal (SVZ-D) and lateral (SVZ-L) regions, which differs from the distributions of neural stem cells in mouse and swine brains. Consistently, RT-qPCR of the biomarker of neural stem cells, Sox2, yields highest expression in SVZ-V ahead of SVZ-D, SVZ-L and AP. These results are discussed with regard to previously published dynamics of adult ovine neurogenesis in vivo, and in light of corresponding features in other mammalian species. This confirms existence of neurogenetic plasticity in the vagal complex of adult mammals.
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Affiliation(s)
- Mahmoud Dahab
- Zoology Department, Faculty of Science, Alexandria University, Alexandria 21151, Egypt; Klinik für Neurologie, Universitätsklinikum Jena, 07747 Jena, Germany; University of Tours, Centre INRAe of Tours, Unit 85 PRC (Physiology of Reproduction and Behavior), 37380 Nouzilly, France
| | - Cyrine Ben-Dhaou
- University of Tours, Centre INRAe of Tours, Unit 85 PRC (Physiology of Reproduction and Behavior), 37380 Nouzilly, France
| | - Maëva Cherif-Feildel
- University of Tours, Centre INRAe of Tours, Unit 85 PRC (Physiology of Reproduction and Behavior), 37380 Nouzilly, France
| | - Marie Moftah
- Zoology Department, Faculty of Science, Alexandria University, Alexandria 21151, Egypt
| | | | - Emmanuel Moyse
- University of Tours, Centre INRAe of Tours, Unit 85 PRC (Physiology of Reproduction and Behavior), 37380 Nouzilly, France.
| | - Sherine Abdel Salam
- Zoology Department, Faculty of Science, Alexandria University, Alexandria 21151, Egypt
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4
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Abatti LE, Lado-Fernández P, Huynh L, Collado M, Hoffman M, Mitchell J. Epigenetic reprogramming of a distal developmental enhancer cluster drives SOX2 overexpression in breast and lung adenocarcinoma. Nucleic Acids Res 2023; 51:10109-10131. [PMID: 37738673 PMCID: PMC10602899 DOI: 10.1093/nar/gkad734] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 08/18/2023] [Accepted: 08/24/2023] [Indexed: 09/24/2023] Open
Abstract
Enhancer reprogramming has been proposed as a key source of transcriptional dysregulation during tumorigenesis, but the molecular mechanisms underlying this process remain unclear. Here, we identify an enhancer cluster required for normal development that is aberrantly activated in breast and lung adenocarcinoma. Deletion of the SRR124-134 cluster disrupts expression of the SOX2 oncogene, dysregulates genome-wide transcription and chromatin accessibility and reduces the ability of cancer cells to form colonies in vitro. Analysis of primary tumors reveals a correlation between chromatin accessibility at this cluster and SOX2 overexpression in breast and lung cancer patients. We demonstrate that FOXA1 is an activator and NFIB is a repressor of SRR124-134 activity and SOX2 transcription in cancer cells, revealing a co-opting of the regulatory mechanisms involved in early development. Notably, we show that the conserved SRR124 and SRR134 regions are essential during mouse development, where homozygous deletion results in the lethal failure of esophageal-tracheal separation. These findings provide insights into how developmental enhancers can be reprogrammed during tumorigenesis and underscore the importance of understanding enhancer dynamics during development and disease.
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Affiliation(s)
- Luis E Abatti
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
| | - Patricia Lado-Fernández
- Laboratory of Cell Senescence, Cancer and Aging, Health Research Institute of Santiago de Compostela (IDIS), Xerencia de Xestión Integrada de Santiago (XXIS/SERGAS), Santiago de Compostela, Spain
- Department of Physiology and Center for Research in Molecular Medicine and Chronic Diseases (CiMUS), Universidade de Santiago de Compostela, Santiago de Compostela, Spain
| | - Linh Huynh
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada
| | - Manuel Collado
- Laboratory of Cell Senescence, Cancer and Aging, Health Research Institute of Santiago de Compostela (IDIS), Xerencia de Xestión Integrada de Santiago (XXIS/SERGAS), Santiago de Compostela, Spain
| | - Michael M Hoffman
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
- Department of Computer Science, University of Toronto, Toronto, Ontario, Canada
- Vector Institute for Artificial Intelligence, Toronto, Ontario, Canada
| | - Jennifer A Mitchell
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
- Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
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5
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Domingo-Muelas A, Morante-Redolat JM, Moncho-Amor V, Jordán-Pla A, Pérez-Villalba A, Carrillo-Barberà P, Belenguer G, Porlan E, Kirstein M, Bachs O, Ferrón SR, Lovell-Badge R, Fariñas I. The rates of adult neurogenesis and oligodendrogenesis are linked to cell cycle regulation through p27-dependent gene repression of SOX2. Cell Mol Life Sci 2023; 80:36. [PMID: 36627412 PMCID: PMC9832098 DOI: 10.1007/s00018-022-04676-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Accepted: 12/15/2022] [Indexed: 01/12/2023]
Abstract
Cell differentiation involves profound changes in global gene expression that often has to occur in coordination with cell cycle exit. Because cyclin-dependent kinase inhibitor p27 reportedly regulates proliferation of neural progenitor cells in the subependymal neurogenic niche of the adult mouse brain, but can also have effects on gene expression, we decided to molecularly analyze its role in adult neurogenesis and oligodendrogenesis. At the cell level, we show that p27 restricts residual cyclin-dependent kinase activity after mitogen withdrawal to antagonize cycling, but it is not essential for cell cycle exit. By integrating genome-wide gene expression and chromatin accessibility data, we find that p27 is coincidentally necessary to repress many genes involved in the transit from multipotentiality to differentiation, including those coding for neural progenitor transcription factors SOX2, OLIG2 and ASCL1. Our data reveal both a direct association of p27 with regulatory sequences in the three genes and an additional hierarchical relationship where p27 repression of Sox2 leads to reduced levels of its downstream targets Olig2 and Ascl1. In vivo, p27 is also required for the regulation of the proper level of SOX2 necessary for neuroblasts and oligodendroglial progenitor cells to timely exit cell cycle in a lineage-dependent manner.
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Affiliation(s)
- Ana Domingo-Muelas
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
- Departamento de Biología Celular Biología Funcional y Antropología Física, Universidad de Valencia, 46100, Burjassot, Spain
- Instituto de Biotecnología y Biomedicina (BioTecMed), Universidad de Valencia, Valencia, Spain
- Department of Cell and Developmental Biology, Smilow Center for Translational Research, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Jose Manuel Morante-Redolat
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
- Departamento de Biología Celular Biología Funcional y Antropología Física, Universidad de Valencia, 46100, Burjassot, Spain
- Instituto de Biotecnología y Biomedicina (BioTecMed), Universidad de Valencia, Valencia, Spain
| | - Verónica Moncho-Amor
- The Francis Crick Institute, London, NW1 1AT, UK
- IIS Biodonostia, 48013, Bilbao, Spain
| | - Antonio Jordán-Pla
- Instituto de Biotecnología y Biomedicina (BioTecMed), Universidad de Valencia, Valencia, Spain
| | - Ana Pérez-Villalba
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
- Departamento de Biología Celular Biología Funcional y Antropología Física, Universidad de Valencia, 46100, Burjassot, Spain
- Instituto de Biotecnología y Biomedicina (BioTecMed), Universidad de Valencia, Valencia, Spain
| | - Pau Carrillo-Barberà
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
- Departamento de Biología Celular Biología Funcional y Antropología Física, Universidad de Valencia, 46100, Burjassot, Spain
- Instituto de Biotecnología y Biomedicina (BioTecMed), Universidad de Valencia, Valencia, Spain
- Institute for Research in Biomedicine, 6500, Bellinzona, Switzerland
| | - Germán Belenguer
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
- Departamento de Biología Celular Biología Funcional y Antropología Física, Universidad de Valencia, 46100, Burjassot, Spain
- Instituto de Biotecnología y Biomedicina (BioTecMed), Universidad de Valencia, Valencia, Spain
- Max Planck Institute of Molecular Cell Biology and Genetics, 01307, Dresden, Germany
| | - Eva Porlan
- Departamento de Biología Molecular, Universidad Autónoma de Madrid (UAM), Madrid, Spain
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid (CSIC-UAM), Madrid, Spain
- Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Instituto de Salud Carlos III, Madrid, Spain
| | - Martina Kirstein
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
- Departamento de Biología Celular Biología Funcional y Antropología Física, Universidad de Valencia, 46100, Burjassot, Spain
- Instituto de Biotecnología y Biomedicina (BioTecMed), Universidad de Valencia, Valencia, Spain
| | - Oriol Bachs
- Department of Biomedical Sciences, University of Barcelona-IDIBAPS, CIBERONC, Barcelona, Spain
| | - Sacri R Ferrón
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
- Departamento de Biología Celular Biología Funcional y Antropología Física, Universidad de Valencia, 46100, Burjassot, Spain
- Instituto de Biotecnología y Biomedicina (BioTecMed), Universidad de Valencia, Valencia, Spain
| | | | - Isabel Fariñas
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain.
- Departamento de Biología Celular Biología Funcional y Antropología Física, Universidad de Valencia, 46100, Burjassot, Spain.
- Instituto de Biotecnología y Biomedicina (BioTecMed), Universidad de Valencia, Valencia, Spain.
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6
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Mahlokozera T, Patel B, Chen H, Desouza P, Qu X, Mao DD, Hafez D, Yang W, Taiwo R, Paturu M, Salehi A, Gujar AD, Dunn GP, Mosammaparast N, Petti AA, Yano H, Kim AH. Competitive binding of E3 ligases TRIM26 and WWP2 controls SOX2 in glioblastoma. Nat Commun 2021; 12:6321. [PMID: 34732716 PMCID: PMC8566473 DOI: 10.1038/s41467-021-26653-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Accepted: 10/18/2021] [Indexed: 12/12/2022] Open
Abstract
The pluripotency transcription factor SOX2 is essential for the maintenance of glioblastoma stem cells (GSC), which are thought to underlie tumor growth, treatment resistance, and recurrence. To understand how SOX2 is regulated in GSCs, we utilized a proteomic approach and identified the E3 ubiquitin ligase TRIM26 as a direct SOX2-interacting protein. Unexpectedly, we found TRIM26 depletion decreased SOX2 protein levels and increased SOX2 polyubiquitination in patient-derived GSCs, suggesting TRIM26 promotes SOX2 protein stability. Accordingly, TRIM26 knockdown disrupted the SOX2 gene network and inhibited both self-renewal capacity as well as in vivo tumorigenicity in multiple GSC lines. Mechanistically, we found TRIM26, via its C-terminal PRYSPRY domain, but independent of its RING domain, stabilizes SOX2 protein by directly inhibiting the interaction of SOX2 with WWP2, which we identify as a bona fide SOX2 E3 ligase in GSCs. Our work identifies E3 ligase competition as a critical mechanism of SOX2 regulation, with functional consequences for GSC identity and maintenance. SOX2 is required for the maintenance of glioblastoma stem cells (GSCs). Here the authors identify that the RING family E3 ubiquitin ligase TRIM26 promotes SOX2 stability in a non-canonical ligase-independent manner and thus, increases the tumorigenicity of GSCs.
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Affiliation(s)
- Tatenda Mahlokozera
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, USA
| | - Bhuvic Patel
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, USA
| | - Hao Chen
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, USA
| | - Patrick Desouza
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, USA
| | - Xuan Qu
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, USA
| | - Diane D Mao
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, USA
| | - Daniel Hafez
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, USA
| | - Wei Yang
- Department of Neurology, Washington University School of Medicine, St. Louis, MO, USA
| | - Rukayat Taiwo
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, USA
| | - Mounica Paturu
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, USA
| | - Afshin Salehi
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, USA
| | - Amit D Gujar
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, USA
| | - Gavin P Dunn
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, USA.,Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA.,The Brain Tumor Center, Siteman Cancer Center, Washington University School of Medicine, St. Louis, MO, USA
| | - Nima Mosammaparast
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Allegra A Petti
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, USA.,The Brain Tumor Center, Siteman Cancer Center, Washington University School of Medicine, St. Louis, MO, USA.,Department of Genetics, Washington University School of Medicine, St. Louis, MO, USA
| | - Hiroko Yano
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, USA. .,Department of Neurology, Washington University School of Medicine, St. Louis, MO, USA. .,The Brain Tumor Center, Siteman Cancer Center, Washington University School of Medicine, St. Louis, MO, USA. .,Department of Genetics, Washington University School of Medicine, St. Louis, MO, USA.
| | - Albert H Kim
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, USA. .,Department of Neurology, Washington University School of Medicine, St. Louis, MO, USA. .,The Brain Tumor Center, Siteman Cancer Center, Washington University School of Medicine, St. Louis, MO, USA. .,Department of Genetics, Washington University School of Medicine, St. Louis, MO, USA. .,Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA.
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7
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Soares MAF, Soares DS, Teixeira V, Heskol A, Bressan RB, Pollard SM, Oliveira RA, Castro DS. Hierarchical reactivation of transcription during mitosis-to-G1 transition by Brn2 and Ascl1 in neural stem cells. Genes Dev 2021; 35:1020-1034. [PMID: 34168041 PMCID: PMC8247608 DOI: 10.1101/gad.348174.120] [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: 12/15/2020] [Accepted: 05/19/2021] [Indexed: 12/19/2022]
Abstract
During mitosis, chromatin condensation is accompanied by a global arrest of transcription. Recent studies suggest transcriptional reactivation upon mitotic exit occurs in temporally coordinated waves, but the underlying regulatory principles have yet to be elucidated. In particular, the contribution of sequence-specific transcription factors (TFs) remains poorly understood. Here we report that Brn2, an important regulator of neural stem cell identity, associates with condensed chromatin throughout cell division, as assessed by live-cell imaging of proliferating neural stem cells. In contrast, the neuronal fate determinant Ascl1 dissociates from mitotic chromosomes. ChIP-seq analysis reveals that Brn2 mitotic chromosome binding does not result in sequence-specific interactions prior to mitotic exit, relying mostly on electrostatic forces. Nevertheless, surveying active transcription using single-molecule RNA-FISH against immature transcripts reveals differential reactivation kinetics for key targets of Brn2 and Ascl1, with transcription onset detected in early (anaphase) versus late (early G1) phases, respectively. Moreover, by using a mitotic-specific dominant-negative approach, we show that competing with Brn2 binding during mitotic exit reduces the transcription of its target gene Nestin Our study shows an important role for differential binding of TFs to mitotic chromosomes, governed by their electrostatic properties, in defining the temporal order of transcriptional reactivation during mitosis-to-G1 transition.
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Affiliation(s)
- Mário A F Soares
- Instituto Gulbenkian de Ciência, 2780-156 Oeiras, Portugal
- i3S Instituto de Investigação e Inovação em Saúde, IBMC Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135 Porto, Portugal
| | - Diogo S Soares
- Instituto Gulbenkian de Ciência, 2780-156 Oeiras, Portugal
- i3S Instituto de Investigação e Inovação em Saúde, IBMC Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135 Porto, Portugal
| | - Vera Teixeira
- Instituto Gulbenkian de Ciência, 2780-156 Oeiras, Portugal
| | - Abeer Heskol
- Instituto Gulbenkian de Ciência, 2780-156 Oeiras, Portugal
- i3S Instituto de Investigação e Inovação em Saúde, IBMC Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135 Porto, Portugal
| | - Raul Bardini Bressan
- Centre for Regenerative Medicine, Institute for Regeneration and Repair, University of Edinburgh, Edinburgh EH16 4UU, United Kingdom
| | - Steven M Pollard
- Centre for Regenerative Medicine, Institute for Regeneration and Repair, University of Edinburgh, Edinburgh EH16 4UU, United Kingdom
| | | | - Diogo S Castro
- Instituto Gulbenkian de Ciência, 2780-156 Oeiras, Portugal
- i3S Instituto de Investigação e Inovação em Saúde, IBMC Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135 Porto, Portugal
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8
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Baklaushev VP, Durov OV, Kalsin VA, Gulaev EV, Kim SV, Gubskiy IL, Revkova VA, Samoilova EM, Melnikov PA, Karal-Ogly DD, Orlov SV, Troitskiy AV, Chekhonin VP, Averyanov AV, Ahlfors JE. Disease modifying treatment of spinal cord injury with directly reprogrammed neural precursor cells in non-human primates. World J Stem Cells 2021; 13:452-469. [PMID: 34136075 PMCID: PMC8176843 DOI: 10.4252/wjsc.v13.i5.452] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 01/20/2021] [Accepted: 04/21/2021] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND The development of regenerative therapy for human spinal cord injury (SCI) is dramatically restricted by two main challenges: the need for a safe source of functionally active and reproducible neural stem cells and the need of adequate animal models for preclinical testing. Direct reprogramming of somatic cells into neuronal and glial precursors might be a promising solution to the first challenge. The use of non-human primates for preclinical studies exploring new treatment paradigms in SCI results in data with more translational relevance to human SCI.
AIM To investigate the safety and efficacy of intraspinal transplantation of directly reprogrammed neural precursor cells (drNPCs).
METHODS Seven non-human primates with verified complete thoracic SCI were divided into two groups: drNPC group (n = 4) was subjected to intraspinal transplantation of 5 million drNPCs rostral and caudal to the lesion site 2 wk post injury, and lesion control (n = 3) was injected identically with the equivalent volume of vehicle.
RESULTS Follow-up for 12 wk revealed that animals in the drNPC group demonstrated a significant recovery of the paralyzed hindlimb as well as recovery of somatosensory evoked potential and motor evoked potential of injured pathways. Magnetic resonance diffusion tensor imaging data confirmed the intraspinal transplantation of drNPCs did not adversely affect the morphology of the central nervous system or cerebrospinal fluid circulation. Subsequent immunohistochemical analysis showed that drNPCs maintained SOX2 expression characteristic of multipotency in the transplanted spinal cord for at least 12 wk, migrating to areas of axon growth cones.
CONCLUSION Our data demonstrated that drNPC transplantation was safe and contributed to improvement of spinal cord function after acute SCI, based on neurological status assessment and neurophysiological recovery within 12 wk after transplantation. The functional improvement described was not associated with neuronal differentiation of the allogeneic drNPCs. Instead, directed drNPCs migration to the areas of active growth cone formation may provide exosome and paracrine trophic support, thereby further supporting the regeneration processes.
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Affiliation(s)
- Vladimir P Baklaushev
- Biomedical Research, Federal Research and Clinical Center of Specialized Medical Care and Medical Technologies, FMBA of Russia, Moscow 115682, Moskva, Russia
| | - Oleg V Durov
- Department of Neurosurgery, Federal Research and Clinical Center of Specialized Medical Care and Medical Technologies, FMBA, Moscow 115682, Moskva, Russia
| | - Vladimir A Kalsin
- Biomedical Research, Federal Research and Clinical Center of Specialized Medical Care and Medical Technologies, FMBA of Russia, Moscow 115682, Moskva, Russia
| | - Eugene V Gulaev
- Department of Neurosurgery, Federal Research and Clinical Center of Specialized Medical Care and Medical Technologies, FMBA, Moscow 115682, Moskva, Russia
| | - Sergey V Kim
- Department of Anesthesiology, N.N.Blokhin Russian Cancer Research Centre, Moscow 115478, Moskva, Russia
| | - Ilya L Gubskiy
- Ilya L Gubskiy, Radiology and Clinical Physiology Scientific Research Center, Federal center of brain research and neurotechnologies of the Federal Medical Biological Agency, Moscow 117997, Russia
| | - Veronika A Revkova
- Biomedical Research, Federal Research and Clinical Center of Specialized Medical Care and Medical Technologies, FMBA of Russia, Moscow 115682, Moskva, Russia
| | - Ekaterina M Samoilova
- Biomedical Research, Federal Research and Clinical Center of Specialized Medical Care and Medical Technologies, FMBA of Russia, Moscow 115682, Moskva, Russia
| | - Pavel A Melnikov
- Department of Neurobiology, Serbsky National Medical Research Center for Psychiatry and Narcology, Moscow 119992, Moskva, Russia
| | - Dzhina D Karal-Ogly
- Department of Primatology, Russian Acad Med Sci, Research Institute of Medical Primatology, Sochi 119992, Sochi, Russia
| | - Sergey V Orlov
- Department of Primatology, Russian Acad Med Sci, Research Institute of Medical Primatology, Sochi 119992, Sochi, Russia
| | - Alexander V Troitskiy
- Department of Vascular Surgery, Federal Research and Clinical Center of Specialized Medical Care and Medical Technologies, FMBA of Russia, Moscow 115682, Moskva, Russia
| | - Vladimir P Chekhonin
- Department of Basic and Applied Neurobiology, V.P. Serbsky Federal Medical Research Center for Psychiatry and Narcology, Russia
- Department of Medical Nanobiotechnology, Pirogov Russian National Research Medical University (RNRMU), Moscow 115682, Moskva, Russia
| | - Alexander V Averyanov
- Biomedical Research, Federal Research and Clinical Center of Specialized Medical Care and Medical Technologies, FMBA of Russia, Moscow 115682, Moskva, Russia
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Saenz-Antoñanzas A, Moncho-Amor V, Auzmendi-Iriarte J, Elua-Pinin A, Rizzoti K, Lovell-Badge R, Matheu A. CRISPR/Cas9 Deletion of SOX2 Regulatory Region 2 ( SRR2) Decreases SOX2 Malignant Activity in Glioblastoma. Cancers (Basel) 2021; 13:cancers13071574. [PMID: 33805518 PMCID: PMC8037847 DOI: 10.3390/cancers13071574] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 03/12/2021] [Accepted: 03/17/2021] [Indexed: 11/16/2022] Open
Abstract
Simple Summary Understanding how SOX2, a major driver of cancer stem cells, is regulated in cancer cells is relevant to tackle tumorigenesis. In this study, we deleted the SRR2 regulatory region in glioblastoma cells. Our data confirm that the SRR2 enhancer regulates SOX2 expression in cancer and reveal that SRR2 deletion halts malignant activity of SOX2. Abstract SOX2 is a transcription factor associated with stem cell activity in several tissues. In cancer, SOX2 expression is increased in samples from several malignancies, including glioblastoma, and high SOX2 levels are associated with the population of tumor-initiating cells and with poor patient outcome. Therefore, understanding how SOX2 is regulated in cancer cells is relevant to tackle tumorigenesis. The SOX2 regulatory region 2(SRR2) is located downstream of the SOX2 coding region and mediates SOX2 expression in embryonic and adult stem cells. In this study, we deleted SRR2 using CRISPR/Cas9 in glioblastoma cells. Importantly, SRR2-deleted glioblastoma cells presented reduced SOX2 expression and decreased proliferative activity and self-renewal capacity in vitro. In line with these results, SRR2-deleted glioblastoma cells displayed decreased tumor initiation and growth in vivo. These effects correlated with an elevation of p21CIP1 cell cycle and p27KIP1 quiescence regulators. In conclusion, our data reveal that SRR2 deletion halts malignant activity of SOX2 and confirms that the SRR2 enhancer regulates SOX2 expression in cancer.
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Affiliation(s)
- Ander Saenz-Antoñanzas
- Cellular Oncology Group, Biodonostia Health Research Institute, 20014 San Sebastian, Spain; (A.S.-A.); (J.A.-I.); (A.E.-P.)
| | - Veronica Moncho-Amor
- Stem Cell Biology and Developmental Genetics Lab, The Francis Crick Institute, London NW1 1AT, UK; (V.M.-A.); (K.R.); (R.L.-B.)
| | - Jaione Auzmendi-Iriarte
- Cellular Oncology Group, Biodonostia Health Research Institute, 20014 San Sebastian, Spain; (A.S.-A.); (J.A.-I.); (A.E.-P.)
| | - Alejandro Elua-Pinin
- Cellular Oncology Group, Biodonostia Health Research Institute, 20014 San Sebastian, Spain; (A.S.-A.); (J.A.-I.); (A.E.-P.)
- Donostia Hospital, 20014 San Sebastian, Spain
| | - Karine Rizzoti
- Stem Cell Biology and Developmental Genetics Lab, The Francis Crick Institute, London NW1 1AT, UK; (V.M.-A.); (K.R.); (R.L.-B.)
| | - Robin Lovell-Badge
- Stem Cell Biology and Developmental Genetics Lab, The Francis Crick Institute, London NW1 1AT, UK; (V.M.-A.); (K.R.); (R.L.-B.)
| | - Ander Matheu
- Cellular Oncology Group, Biodonostia Health Research Institute, 20014 San Sebastian, Spain; (A.S.-A.); (J.A.-I.); (A.E.-P.)
- CIBER of Frailty and Healthy Aging (CIBERfes), Carlos III Institute, 28029 Madrid, Spain
- IKERBASQUE, Basque Foundation for Science, 48009 Bilbao, Spain
- Correspondence:
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10
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Batool S, Kayani MA, Valis M, Kuca K. Neural Differentiation of Mouse Embryonic Stem Cells-An in vitro Approach to Profile DNA Methylation of Reprogramming Factor Sox2-SRR2. Front Genet 2021; 12:641095. [PMID: 33828585 PMCID: PMC8019947 DOI: 10.3389/fgene.2021.641095] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Accepted: 03/02/2021] [Indexed: 12/30/2022] Open
Abstract
Sox2 is one of the core transcription factors maintaining the embryonic stem cells (ES) pluripotency and, also indispensable for cellular reprogramming. However, limited data is available about the DNA methylation of pluripotency genes during lineage-specific differentiations. This study investigated the DNA methylation of Sox2 regulatory region 2 (SRR2) during directed differentiation of mouse ES into neural lineage. ES cells were first grown to form embryoid bodies in suspension which were then dissociated, and cultured in defined medium to promote neural differentiation. Typical neuronal morphology together with the up-regulation of Pax6, neuroepithelial stem cell intermediate filament and β-tubulin III and, down-regulation of pluripotency genes Oct4, Nanog and Sox2 showed the existence of neural phenotype in cells undergoing differentiation. Three CpGs in the core enhancer region of neural-specific SRR2 were individually investigated by direct DNA sequencing post-bisulfite treatment and, found to be unmethylated in differentiated cells at time-points chosen for analysis. This analysis does not limit the possibility of methylation at other CpG sites than those profiled here and/or transient methylation. Hence, similar analyses exploring the DNA methylation at other regions of the Sox2 gene could unravel the onset and transitions of epigenetic signatures influencing the outcome of differentiation pathways and neural development. The data presented here shows that in vitro neural differentiation of embryonic stem cells can be employed to study and characterize molecular regulatory mechanisms governing neurogenesis by applying diverse pharmacological and toxicological agents.
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Affiliation(s)
- Sajida Batool
- Cancer Genetics and Epigenetics Laboratory, Department of Biosciences, COMSATS University Islamabad, Islamabad, Pakistan
| | - Mahmood Akhtar Kayani
- Cancer Genetics and Epigenetics Laboratory, Department of Biosciences, COMSATS University Islamabad, Islamabad, Pakistan
| | - Martin Valis
- Department of Neurology of the Medical Faculty of Charles University and University Hospital in Hradec Kralove, Hradec Kralove, Czechia
| | - Kamil Kuca
- Department of Chemistry, University of Hradec Kralove, Hradec Kralove, Czechia
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11
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Functional characterization of SOX2 as an anticancer target. Signal Transduct Target Ther 2020; 5:135. [PMID: 32728033 PMCID: PMC7391717 DOI: 10.1038/s41392-020-00242-3] [Citation(s) in RCA: 94] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 06/01/2020] [Accepted: 06/22/2020] [Indexed: 02/07/2023] Open
Abstract
SOX2 is a well-characterized pluripotent factor that is essential for stem cell self-renewal, reprogramming, and homeostasis. The cellular levels of SOX2 are precisely regulated by a complicated network at the levels of transcription, post-transcription, and post-translation. In many types of human cancer, SOX2 is dysregulated due to gene amplification and protein overexpression. SOX2 overexpression is associated with poor survival of cancer patients. Mechanistically, SOX2 promotes proliferation, survival, invasion/metastasis, cancer stemness, and drug resistance. SOX2 is, therefore, an attractive anticancer target. However, little progress has been made in the efforts to discover SOX2 inhibitors, largely due to undruggable nature of SOX2 as a transcription factor. In this review, we first briefly introduced SOX2 as a transcription factor, its domain structure, normal physiological functions, and its involvement in human cancers. We next discussed its role in embryonic development and stem cell-renewal. We then mainly focused on three aspects of SOX2: (a) the regulatory mechanisms of SOX2, including how SOX2 level is regulated, and how SOX2 cross-talks with multiple signaling pathways to control growth and survival; (b) the role of SOX2 in tumorigenesis and drug resistance; and (c) current drug discovery efforts on targeting SOX2, and the future perspectives to discover specific SOX2 inhibitors for effective cancer therapy.
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12
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Metastatic Phosphatase PRL-3 Induces Ovarian Cancer Stem Cell Sub-population through Phosphatase-Independent Deacetylation Modulations. iScience 2019; 23:100766. [PMID: 31887658 PMCID: PMC6941878 DOI: 10.1016/j.isci.2019.100766] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 09/01/2019] [Accepted: 12/09/2019] [Indexed: 12/18/2022] Open
Abstract
Cancer stem cells (CSCs) are responsible for tumor initiation, chemoresistance, metastasis, and relapse, but the underlying molecular origin of CSCs remains elusive. Here we identified that metastatic phosphatase of regenerating liver 3 (PRL-3) transcriptionally upregulates SOX2 in the expansion of CSC sub-population from normal cancer cells. Mechanistically, SOX2 upregulation is attributed to the binding of the acetylated myocyte enhancer factor 2A (MEF2A) to SOX2 promoter in tumor cells. In parallel, PRL-3 competitively binds to Class IIa histone deacetylase 4 (HDAC4) to facilitate HDAC4 translocation, leading to the disassociation of HDAC4 from MEF2A and histones. The released MEF2A and histones thus remain acetylated and render the subsequent accessibility of the acetylated MEF2A to SOX2 promoter region. Clinical relevance among PRL-3, SOX2, and HDAC4 is validated in ovary cancer samples. Therefore, this PRL-3-HDAC4-MEF2A/histones-SOX2 signaling axis would be a potential therapeutic target in inhibiting ovarian cancer metastasis and relapse. PRL-3 promotes the expansion of CSC-like cells via transcriptional SOX2 upregulation Binding of MEF2A to SOX2 promoter bridges the PRL-3-induced SOX2 upregulation PRL-3 competitively binds HDAC4 to cause the disassociation of HDAC4 from MEF2A Acetylated histones render the accessibility of SOX2 promoter region to MEF2A
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13
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Xu R, Chen L, Yang WT. Aberrantly elevated Bmi1 promotes cervical cancer tumorigenicity and tumor sphere formation via enhanced transcriptional regulation of Sox2 genes. Oncol Rep 2019; 42:688-696. [PMID: 31173263 PMCID: PMC6609343 DOI: 10.3892/or.2019.7188] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2018] [Accepted: 05/30/2019] [Indexed: 12/24/2022] Open
Abstract
The exact molecular mechanisms underlying cervical tumorigenesis are poorly understood. Polycomb complex protein Bmi1 (Bmi1) is involved in the malignant transformation and biological aggressiveness of several human carcinomas. Therefore, the present study assessed the expression of Bmi1 protein in human cervical cancer tissues and examined the mechanisms involved in cervical carcinogenesis. The expression of Bmi1 protein was examined by immunohistochemistry in cervical carcinoma tissues (n=71), high-grade squamous intraepithelial lesions (n=41) and normal cervical tissues (n=47). Expression of Bmi1 protein gradually increased across samples from the normal cervix (1/47; 2.12%), high-grade squamous intraepithelial lesions (5/42; 16.13%) and cervical carcinomas (31/71; 43.66%; P<0.05). Additionally, Bmi1 protein expression was associated with tumor histopathological grade. The effects of Bmi1 silencing and overexpression on tumor sphere formation and the tumorigenicity of cervical cancer cells were investigated. Overexpression of Bmi1 resulted in significantly attenuated tumor formation and tumor sphere formation. Consistently, Bmi1 silencing significantly inhibited tumor formation and tumor sphere formation. Furthermore, Bmi1 upregulated the expression of Sox2, and the dual-luciferase reporter assay and chromatin immunoprecipitation showed that Bmi1 transactivated Sox2 by binding to the two E-box motifs in the Sox2 promoter. In conclusion, aberrantly elevated Bmi1 promotes cervical cancer tumorigenicity and tumor sphere formation via enhanced transcriptional regulation of Sox2 genes as a potential oncogenic factor that participates in the carcinogenesis of cervical carcinomas.
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Affiliation(s)
- Rui Xu
- Department of Reproductive Medicine, The First Affiliated Hospital of the Medical College, Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China
| | - Lin Chen
- Department of Pathology, Shaanxi Provincial People's Hospital, Xi'an, Shaanxi 710061, P.R. China
| | - Wen-Ting Yang
- Department of Reproductive Medicine, The First Affiliated Hospital of the Medical College, Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China
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14
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Lee C, Robinson M, Willerth SM. Direct Reprogramming of Glioblastoma Cells into Neurons Using Small Molecules. ACS Chem Neurosci 2018; 9:3175-3185. [PMID: 30091580 DOI: 10.1021/acschemneuro.8b00365] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Glioblastoma multiforme, a type of deadly brain cancer, originates most commonly from astrocytes found in the brain. Current multimodal treatments for glioblastoma minimally increase life expectancy, but significant advancements in prognosis have not been made in the past few decades. Here we investigate cellular reprogramming for inhibiting the aggressive proliferation of glioblastoma cells. Cellular reprogramming converts one differentiated cell type into another type based on the principles of regenerative medicine. In this study, we used cellular reprogramming to investigate whether small molecule mediated reprogramming could convert glioblastoma cells into neurons. We investigated a novel method for reprogramming U87MG human glioblastoma cells into terminally differentiated neurons using a small molecule cocktail consisting of forskolin, ISX9, CHIR99021 I-BET 151, and DAPT. Treating U87MG glioblastoma cells with this cocktail successfully reprogrammed the malignant cells into early neurons over 13 days. The reprogrammed cells displayed morphological and immunofluorescent characteristics associated with neuronal phenotypes. Genetic analysis revealed that the chemical cocktail upregulates the Ngn2, Ascl1, Brn2, and MAP2 genes, resulting in neuronal reprogramming. Furthermore, these cells displayed decreased viability and lacked the ability to form high numbers of tumor-like spheroids. Overall, this study validates the use of a novel small molecule cocktail for reprogramming glioblastoma into nonproliferating neurons.
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Affiliation(s)
- Christopher Lee
- Department of Biology, University of Victoria, Victoria, BC V8W 2Y2, Canada
| | - Meghan Robinson
- Division of Medical Sciences, University of Victoria, Victoria, BC V8W 2Y2, Canada
| | - Stephanie M. Willerth
- Department of Mechanical Engineering, University of Victoria, Victoria, BC V8W 2Y2, Canada
- Division of Medical Sciences, University of Victoria, Victoria, BC V8W 2Y2, Canada
- Centre for Biomedical Research, University of Victoria, Victoria, BC V8W 2Y2, Canada
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
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15
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Identification and expression of transcription factor sox2 in large yellow croaker Larimichthys crocea. Theriogenology 2018; 120:123-137. [PMID: 30118947 DOI: 10.1016/j.theriogenology.2018.07.025] [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] [Received: 01/22/2018] [Revised: 07/21/2018] [Accepted: 07/23/2018] [Indexed: 12/25/2022]
Abstract
As an important transcription and pluripotency factor, Sox2 plays its functions essentially in the regulation of self-renewal and pluripotency of embryonic and neural stem cells, as well as embryogenesis, organogenesis, neurogenesis and regeneration. The data is lacking on Sox2 in large yellow croaker (Larimichthys crocea) (Lc-Sox2) which is a limitation on the generation of induced pluripotent stem cells (iPSCs). In this study, Lc-sox2 was cloned by RACE (rapid amplification of cDNA ends) and analyzed by Bioinformatics. The quantitative real-time PCR (qRT-PCR) and whole mount in situ hybridization (WISH) were used to detect the expression of Lc-sox2. The full-length cDNA sequence of Lc-sox2 is 2135 bp and encodes a 322-aa (amino acids). Lc-Sox2 possesses a highly conserved HMG-box as DNA-binding domain, maintains highly conserved with vertebrates, particularly with teleosts. In tissues, Lc-sox2 was expressed with gender difference in brain and eye (female > male), in embryos, Lc-sox2 was expressed with a zygotic type that the high level expression began to appear in the gastrula stage. The spatio-temporal expression patterns of Lc-sox2 suggested the potential involvement in embryogenesis, neurogenesis, gametogenesis and adult physiological processes of large yellow croaker. Our results contributed to better understanding of Sox2 from large yellow croaker.
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16
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Knauss JL, Miao N, Kim SN, Nie Y, Shi Y, Wu T, Pinto HB, Donohoe ME, Sun T. Long noncoding RNA Sox2ot and transcription factor YY1 co-regulate the differentiation of cortical neural progenitors by repressing Sox2. Cell Death Dis 2018; 9:799. [PMID: 30038234 PMCID: PMC6056501 DOI: 10.1038/s41419-018-0840-2] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 06/04/2018] [Accepted: 06/18/2018] [Indexed: 01/08/2023]
Abstract
Long noncoding RNAs (lncRNAs) are emerging as key regulators of crucial cellular processes. However, the molecular mechanisms of many lncRNA functions remain uncharacterized. Sox2ot is an evolutionarily conserved lncRNA that transcriptionally overlaps the pluripotency gene Sox2, which maintains the stemness of embryonic stem cells and tissue-specific stem cells. Here, we show that Sox2ot is expressed in the developing mouse cerebral cortex, where it represses neural progenitor (NP) proliferation and promotes neuronal differentiation. Sox2ot negatively regulates self-renewal of neural stem cells, and is predominately expressed in the nucleus and inhibits Sox2 levels. Sox2ot forms a physical interaction with a multifunctional transcriptional regulator YY1, which binds several CpG islands in the Sox2 locus in a Sox2ot-dependent manner. Similar to Sox2ot, YY1 represses NP expansion in vivo. These results demonstrate a regulatory role of Sox2ot in promoting cortical neurogenesis, possibly by repressing Sox2 expression in NPs, through interacting with YY1.
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Affiliation(s)
- Jennifer L Knauss
- Department of Cell and Developmental Biology, Cornell University Weill Medical College, 1300 York Avenue, Box 60, New York, NY, 10065, USA
| | - Nan Miao
- Center for Precision Medicine, School of Medicine and School of Biomedical Sciences, Huaqiao University, Xiamen, China, 361021
| | - Seung-Nam Kim
- Department of Cell and Developmental Biology, Cornell University Weill Medical College, 1300 York Avenue, Box 60, New York, NY, 10065, USA
- College of Korean Medicine, Dongguk University, Ilsandonggu, Goyangsi, 10326, Gyeonggido, Korea
| | - Yanzhen Nie
- School of Life Sciences and Technology, Shanghai Jiao Tong University, Shanghai, China, 200240
| | - Yuelin Shi
- School of Life Sciences and Technology, Shanghai Jiao Tong University, Shanghai, China, 200240
| | - Tao Wu
- Burke Medical Research Institute, 785 Mamaroneck Avenue, White Plains, NY, 10605, USA
- Department of Neuroscience, Department of Cell and Developmental Biology, Cornell University Weill Medical College, 1300 York Avenue, New York, NY, 10065, USA
| | - Hugo Borges Pinto
- Burke Medical Research Institute, 785 Mamaroneck Avenue, White Plains, NY, 10605, USA
- Department of Neuroscience, Department of Cell and Developmental Biology, Cornell University Weill Medical College, 1300 York Avenue, New York, NY, 10065, USA
| | - Mary E Donohoe
- Burke Medical Research Institute, 785 Mamaroneck Avenue, White Plains, NY, 10605, USA
- Department of Neuroscience, Department of Cell and Developmental Biology, Cornell University Weill Medical College, 1300 York Avenue, New York, NY, 10065, USA
| | - Tao Sun
- Department of Cell and Developmental Biology, Cornell University Weill Medical College, 1300 York Avenue, Box 60, New York, NY, 10065, USA.
- Center for Precision Medicine, School of Medicine and School of Biomedical Sciences, Huaqiao University, Xiamen, China, 361021.
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17
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Wuebben EL, Rizzino A. The dark side of SOX2: cancer - a comprehensive overview. Oncotarget 2018; 8:44917-44943. [PMID: 28388544 PMCID: PMC5546531 DOI: 10.18632/oncotarget.16570] [Citation(s) in RCA: 151] [Impact Index Per Article: 25.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Accepted: 03/16/2017] [Indexed: 12/14/2022] Open
Abstract
The pluripotency-associated transcription factor SOX2 is essential during mammalian embryogenesis and later in life, but SOX2 expression can also be highly detrimental. Over the past 10 years, SOX2 has been shown to be expressed in at least 25 different cancers. This review provides a comprehensive overview of the roles of SOX2 in cancer and focuses on two broad topics. The first delves into the expression and function of SOX2 in cancer focusing on the connection between SOX2 levels and tumor grade as well as patient survival. As part of this discussion, we address the developing connection between SOX2 expression and tumor drug resistance. We also call attention to an under-appreciated property of SOX2, its levels in actively proliferating tumor cells appear to be optimized to maximize tumor growth - too little or too much SOX2 dramatically alters tumor growth. The second topic of this review focuses on the exquisite array of molecular mechanisms that control the expression and transcriptional activity of SOX2. In addition to its complex regulation at the transcriptional level, SOX2 expression and activity are controlled carefully by microRNAs, long non-coding RNAs, and post-translational modifications. In the Conclusion and Future Perspectives section, we point out that there are still important unanswered questions. Addressing these questions is expected to lead to new insights into the functions of SOX2 in cancer, which will help design novels strategies for more effectively treating some of the most deadly cancers.
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Affiliation(s)
- Erin L Wuebben
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Angie Rizzino
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, Nebraska, USA.,Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, Nebraska, USA
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18
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Cyclin-Dependent Kinase-Dependent Phosphorylation of Sox2 at Serine 39 Regulates Neurogenesis. Mol Cell Biol 2017; 37:MCB.00201-17. [PMID: 28584195 DOI: 10.1128/mcb.00201-17] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 05/25/2017] [Indexed: 01/05/2023] Open
Abstract
Sox2 is known to be important for neuron formation, but the precise mechanism through which it activates a neurogenic program and how this differs from its well-established function in self-renewal of stem cells remain elusive. In this study, we identified a highly conserved cyclin-dependent kinase (Cdk) phosphorylation site on serine 39 (S39) in Sox2. In neural stem cells (NSCs), phosphorylation of S39 enhances the ability of Sox2 to negatively regulate neuronal differentiation, while loss of phosphorylation is necessary for chromatin retention of a truncated form of Sox2 generated during neurogenesis. We further demonstrated that nonphosphorylated cleaved Sox2 specifically induces the expression of proneural genes and promotes neurogenic commitment in vivo Our present study sheds light on how the level of Cdk kinase activity directly regulates Sox2 to tip the balance between self-renewal and differentiation in NSCs.
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Liu W, Song H, Li A, Du X, Liu Y, He Y, Zhang Q, Qi J. Functional characterization of the Japanese flounder (Paralichthys olivaceus) Sox2 gene promoter. FISH PHYSIOLOGY AND BIOCHEMISTRY 2016; 42:1275-1285. [PMID: 26961126 DOI: 10.1007/s10695-016-0216-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Accepted: 02/28/2016] [Indexed: 06/05/2023]
Abstract
Sox2 has essential roles in early embryogenesis and the development of the central nervous system. Sox2 is also necessary in maintaining the identity of progenitor cells. In our study, a 1.8-kb fragment of the 5' flanking region of Paralichthys olivaceus Sox2 (Po-Sox2) gene was cloned and functionally characterized. The activity and specificity of Po-Sox2 promoter were analyzed by comparing various deletion mutants for their ability to direct luciferase and GFP expression in flounder brain cell line. Results indicated that the basal promoter is located between -978 and -442 bp, and the region from -1370 to -978 bp enhances the promoter activity. The regulatory elements in the -1370 to -442 bp fragment were further investigated. Many binding sites of transcription factors closely related to neurogenesis and stem cell properties were found in this region. Mutational analysis indicated that Nanog, Pax6, p53, and POU binding sites play functional roles in the transcription of Po-Sox2 gene, whereas NF-Y binding sites did not affect this gene. In vivo studies using transient transgenic zebrafish embryos showed that the Po-Sox2 promoter region can drive GFP expression in brain, yolk syncytial layer, and notochord. Our results provide valuable information in understanding the molecular regulatory mechanisms of Po-Sox2 gene during neurogenesis and embryonic development.
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Affiliation(s)
- Wei Liu
- Key Laboratory of Marine Genetics and Breeding (Ocean University of China), Ministry of Education, Qingdao, 266003, China
| | - Huayu Song
- Key Laboratory of Marine Genetics and Breeding (Ocean University of China), Ministry of Education, Qingdao, 266003, China
| | - Aoyun Li
- Key Laboratory of Marine Genetics and Breeding (Ocean University of China), Ministry of Education, Qingdao, 266003, China
| | - Xinxin Du
- Key Laboratory of Marine Genetics and Breeding (Ocean University of China), Ministry of Education, Qingdao, 266003, China
| | - Yuezhong Liu
- Key Laboratory of Marine Genetics and Breeding (Ocean University of China), Ministry of Education, Qingdao, 266003, China
| | - Yan He
- Key Laboratory of Marine Genetics and Breeding (Ocean University of China), Ministry of Education, Qingdao, 266003, China
| | - Quanqi Zhang
- Key Laboratory of Marine Genetics and Breeding (Ocean University of China), Ministry of Education, Qingdao, 266003, China
| | - Jie Qi
- Key Laboratory of Marine Genetics and Breeding (Ocean University of China), Ministry of Education, Qingdao, 266003, China.
- College of Marine Life Science, Ocean University of China, No. 5 Yushan Road, Qingdao, 266003, China.
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20
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Semerci F, Maletic-Savatic M. Transgenic mouse models for studying adult neurogenesis. ACTA ACUST UNITED AC 2016; 11:151-167. [PMID: 28473846 DOI: 10.1007/s11515-016-1405-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The mammalian hippocampus shows a remarkable capacity for continued neurogenesis throughout life. Newborn neurons, generated by the radial neural stem cells (NSCs), are important for learning and memory as well as mood control. During aging, the number and responses of NSCs to neurogenic stimuli diminish, leading to decreased neurogenesis and age-associated cognitive decline and psychiatric disorders. Thus, adult hippocampal neurogenesis has garnered significant interest because targeting it could be a novel potential therapeutic strategy for these disorders. However, if we are to use neurogenesis to halt or reverse hippocampal-related pathology, we need to understand better the core molecular machinery that governs NSC and their progeny. In this review, we summarize a wide variety of mouse models used in adult neurogenesis field, present their advantages and disadvantages based on specificity and efficiency of labeling of different cell types, and review their contribution to our understanding of the biology and the heterogeneity of different cell types found in adult neurogenic niches.
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Affiliation(s)
- Fatih Semerci
- Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030, USA.,Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA
| | - Mirjana Maletic-Savatic
- Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030, USA.,Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA.,Department of Pediatrics-Neurology, Department of Neuroscience, and Structural and Computational Biology and Molecular Biophysics, Baylor College of Medicine, Houston, TX 77030, USA
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21
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Bora-Singhal N, Nguyen J, Schaal C, Perumal D, Singh S, Coppola D, Chellappan S. YAP1 Regulates OCT4 Activity and SOX2 Expression to Facilitate Self-Renewal and Vascular Mimicry of Stem-Like Cells. Stem Cells 2016; 33:1705-18. [PMID: 25754111 DOI: 10.1002/stem.1993] [Citation(s) in RCA: 131] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Revised: 02/02/2015] [Accepted: 02/18/2015] [Indexed: 12/14/2022]
Abstract
Non-small cell lung cancer (NSCLC) is highly correlated with smoking and has very low survival rates. Multiple studies have shown that stem-like cells contribute to the genesis and progression of NSCLC. Our results show that the transcriptional coactivator yes-associated protein 1 (YAP1), which is the oncogenic component of the Hippo signaling pathway, is elevated in the stem-like cells from NSCLC and contributes to their self-renewal and ability to form angiogenic tubules. Inhibition of YAP1 by a small molecule or depletion of YAP1 by siRNAs suppressed self-renewal and vascular mimicry of stem-like cells. These effects of YAP1 were mediated through the embryonic stem cell transcription factor, Sox2. YAP1 could transcriptionally induce Sox2 through a physical interaction with Oct4; Sox2 induction occurred independent of TEAD2 transcription factor, which is the predominant mediator of YAP1 functions. The binding of Oct4 to YAP1 could be detected in cell lines as well as tumor tissues; the interaction was elevated in NSCLC samples compared to normal tissue as seen by proximity ligation assays. YAP1 bound to Oct4 through the WW domain, and a peptide corresponding to this region could disrupt the interaction. Delivery of the WW domain peptide to stem-like cells disrupted the interaction and abrogated Sox2 expression, self-renewal, and vascular mimicry. Depleting YAP1 reduced the expression of multiple epithelial-mesenchymal transition genes and prevented the growth and metastasis of tumor xenografts in mice; overexpression of Sox2 in YAP1 null cells rescued these functions. These results demonstrate a novel regulation of stem-like functions by YAP1, through the modulation of Sox2 expression.
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Affiliation(s)
- Namrata Bora-Singhal
- Department of Tumor Biology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida, USA
| | - Jonathan Nguyen
- Department of Tumor Biology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida, USA
| | - Courtney Schaal
- Department of Tumor Biology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida, USA
| | - Deepak Perumal
- Department of Hematology & Medical Oncology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Sandeep Singh
- National Institute of Biomedical Genomics, Kalyani, West Bengal, India
| | - Domenico Coppola
- Department of Anatomic Pathology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida, USA
| | - Srikumar Chellappan
- Department of Tumor Biology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida, USA
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22
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Bery A, Mérot Y, Rétaux S. Genes expressed in mouse cortical progenitors are enriched in Pax, Lhx, and Sox transcription factor putative binding sites. Brain Res 2015; 1633:37-51. [PMID: 26721689 DOI: 10.1016/j.brainres.2015.12.022] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Revised: 11/25/2015] [Accepted: 12/14/2015] [Indexed: 11/19/2022]
Abstract
Considerable progress has been made in the understanding of molecular and cellular mechanisms controlling the development of the mammalian cortex. The proliferative and neurogenic properties of cortical progenitors located in the ventricular germinal zone start being understood. Little is known however on the cis-regulatory control that finely tunes gene expression in these progenitors. Here, we undertook an in silico-based approach to address this question, followed by some functional validation. Using the Eurexpress database, we established a list of 30 genes specifically expressed in the cortical germinal zone, we selected mouse/human conserved non-coding elements (CNEs) around these genes and we performed motif-enrichment search in these CNEs. We found an over-representation of motifs corresponding to binding sites for Pax, Sox, and Lhx transcription factors, often found as pairs and located within 100bp windows. A small subset of CNEs (n=7) was tested for enhancer activity, by ex-vivo and in utero electroporation assays. Two showed strong enhancer activity in the germinal zone progenitors. Mutagenesis experiments on a selected CNE showed the functional importance of the Pax, Sox, and Lhx TFBS for conferring enhancer activity to the CNE. Overall, from a cis-regulatory viewpoint, our data suggest an input from Pax, Sox and Lhx transcription factors to orchestrate corticogenesis. These results are discussed with regards to the known functional roles of Pax6, Sox2 and Lhx2 in cortical development.
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Affiliation(s)
- Amandine Bery
- DECA Group, Institut des Neurosciences Paris-Saclay, Université Paris-Saclay, Université Paris-Sud, CNRS, UMR 9197, 91198 Gif-sur-Yvette, France.
| | - Yohann Mérot
- DECA Group, Institut des Neurosciences Paris-Saclay, Université Paris-Saclay, Université Paris-Sud, CNRS, UMR 9197, 91198 Gif-sur-Yvette, France
| | - Sylvie Rétaux
- DECA Group, Institut des Neurosciences Paris-Saclay, Université Paris-Saclay, Université Paris-Sud, CNRS, UMR 9197, 91198 Gif-sur-Yvette, France.
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23
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Repetitive magnetic stimulation promotes neural stem cells proliferation by upregulating MiR-106b in vitro. ACTA ACUST UNITED AC 2015; 35:766-772. [PMID: 26489637 DOI: 10.1007/s11596-015-1505-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Revised: 03/10/2015] [Indexed: 10/22/2022]
Abstract
Neural stem cells (NSCs) proliferation can be influenced by repetitive transcranial magnetic stimulation (rTMS) in vivo via microRNA-106b-25 cluster, but the underlying mechanisms are poorly understood. This study investigated the involvement of microRNA-106b-25 cluster in the proliferation of NSCs after repetitive magnetic stimulation (rMS) in vitro. NSCs were stimulated by rMS (200/400/600/800/1000 pulses per day, with 10 Hz frequency and 50% maximum machine output) over a 3-day period. NSCs proliferation was detected by using ki-67 and EdU staining. Ki-67, p21, p57, cyclinD1, cyclinE, cyclinA, cdk2, cdk4 proteins and miR-106b, miR-93, miR-25 mRNAs were detected by Western blotting and qRT-PCR, respectively. The results showed that rMS could promote NSCs proliferation in a dose-dependent manner. The proportions of ki-67+ and Edu+ cells in 1000 pulses group were 20.65% and 4.00%, respectively, significantly higher than those in control group (9.25%, 2.05%). The expression levels of miR-106b and miR-93 were significantly upregulated in 600-1000 pulses groups compared with control group (P<0.05 or 0.01 for all). The expression levels of p21 protein were decreased significantly in 800/1000 pulses groups, and those of cyclinD1, cyclinA, cyclinE, cdk2 and cdk4 were obviously increased after rMS as compared with control group (P<0.05 or 0.01 for all). In conclusion, our findings suggested that rMS enhances the NSCs proliferation in vitro in a dose-dependent manner and miR-106b/p21/cdks/cyclins pathway was involved in the process.
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24
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Zhao C, Ma D, Zawadzka M, Fancy SPJ, Elis-Williams L, Bouvier G, Stockley JH, de Castro GM, Wang B, Jacobs S, Casaccia P, Franklin RJM. Sox2 Sustains Recruitment of Oligodendrocyte Progenitor Cells following CNS Demyelination and Primes Them for Differentiation during Remyelination. J Neurosci 2015; 35:11482-99. [PMID: 26290228 PMCID: PMC6605237 DOI: 10.1523/jneurosci.3655-14.2015] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Revised: 05/27/2015] [Accepted: 06/21/2015] [Indexed: 12/16/2022] Open
Abstract
The Sox family of transcription factors have been widely studied in the context of oligodendrocyte development. However, comparatively little is known about the role of Sox2, especially during CNS remyelination. Here we show that the expression of Sox2 occurs in oligodendrocyte progenitor cells (OPCs) in rodent models during myelination and in activated adult OPCs responding to demyelination, and is also detected in multiple sclerosis lesions. In normal adult white matter of both mice and rats, it is neither expressed by adult OPCs nor by oligodendrocytes (although it is expressed by a subpopulation of adult astrocytes). Overexpression of Sox2 in rat OPCs in vitro maintains the cells in a proliferative state and inhibits differentiation, while Sox2 knockout results in decreased OPC proliferation and survival, suggesting that Sox2 contributes to the expansion of OPCs during the recruitment phase of remyelination. Loss of function in cultured mouse OPCs also results in an impaired ability to undergo normal differentiation in response to differentiation signals, suggesting that Sox2 expression in activated OPCs also primes these cells to eventually undergo differentiation. In vivo studies on remyelination following experimental toxin-induced demyelination in mice with inducible loss of Sox2 revealed impaired remyelination, which was largely due to a profound attenuation of OPC recruitment and likely also due to impaired differentiation. Our results reveal a key role of Sox2 expression in OPCs responding to demyelination, enabling them to effectively contribute to remyelination. SIGNIFICANCE STATEMENT Understanding the mechanisms of CNS remyelination is central to developing effective means by which this process can be therapeutically enhanced in chronic demyelinating diseases such as multiple sclerosis. In this study, we describe the role of Sox2, a transcription factor widely implicated in stem cell biology, in CNS myelination and remyelination. We show how Sox2 is expressed in oligodendrocyte progenitor cells (OPCs) preparing to undergo differentiation, allowing them to undergo proliferation and priming them for subsequent differentiation. Although Sox2 is unlikely to be a direct therapeutic target, these data nevertheless provide more information on how OPC differentiation is controlled and therefore enriches our understanding of this important CNS regenerative process.
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Affiliation(s)
- Chao Zhao
- Wellcome Trust-Medical Research Council Stem Cell Institute and Department of Clinical Neurosciences, University of Cambridge, Cambridge Biomedical Campus, Cambridge CB2 0AH, United Kingdom, and
| | - Dan Ma
- Wellcome Trust-Medical Research Council Stem Cell Institute and Department of Clinical Neurosciences, University of Cambridge, Cambridge Biomedical Campus, Cambridge CB2 0AH, United Kingdom, and
| | - Malgorzata Zawadzka
- Wellcome Trust-Medical Research Council Stem Cell Institute and Department of Clinical Neurosciences, University of Cambridge, Cambridge Biomedical Campus, Cambridge CB2 0AH, United Kingdom, and
| | - Stephen P J Fancy
- Wellcome Trust-Medical Research Council Stem Cell Institute and Department of Clinical Neurosciences, University of Cambridge, Cambridge Biomedical Campus, Cambridge CB2 0AH, United Kingdom, and
| | - Lowri Elis-Williams
- Wellcome Trust-Medical Research Council Stem Cell Institute and Department of Clinical Neurosciences, University of Cambridge, Cambridge Biomedical Campus, Cambridge CB2 0AH, United Kingdom, and
| | - Guy Bouvier
- Wellcome Trust-Medical Research Council Stem Cell Institute and Department of Clinical Neurosciences, University of Cambridge, Cambridge Biomedical Campus, Cambridge CB2 0AH, United Kingdom, and
| | - John H Stockley
- Wellcome Trust-Medical Research Council Stem Cell Institute and Department of Clinical Neurosciences, University of Cambridge, Cambridge Biomedical Campus, Cambridge CB2 0AH, United Kingdom, and
| | - Glaucia Monteiro de Castro
- Wellcome Trust-Medical Research Council Stem Cell Institute and Department of Clinical Neurosciences, University of Cambridge, Cambridge Biomedical Campus, Cambridge CB2 0AH, United Kingdom, and
| | - Bowei Wang
- Wellcome Trust-Medical Research Council Stem Cell Institute and Department of Clinical Neurosciences, University of Cambridge, Cambridge Biomedical Campus, Cambridge CB2 0AH, United Kingdom, and
| | - Sabrina Jacobs
- Wellcome Trust-Medical Research Council Stem Cell Institute and Department of Clinical Neurosciences, University of Cambridge, Cambridge Biomedical Campus, Cambridge CB2 0AH, United Kingdom, and
| | - Patrizia Casaccia
- Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York 10029-6574
| | - Robin J M Franklin
- Wellcome Trust-Medical Research Council Stem Cell Institute and Department of Clinical Neurosciences, University of Cambridge, Cambridge Biomedical Campus, Cambridge CB2 0AH, United Kingdom, and
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25
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Yamamizu K, Schlessinger D, Ko MSH. SOX9 accelerates ESC differentiation to three germ layer lineages by repressing SOX2 expression through P21 (WAF1/CIP1). Development 2015; 141:4254-66. [PMID: 25371362 DOI: 10.1242/dev.115436] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Upon removal of culture conditions that maintain an undifferentiated state, mouse embryonic stem cells (ESCs) differentiate into various cell types. Differentiation can be facilitated by forced expression of certain transcription factors (TFs), each of which can generally specify a particular developmental lineage. We previously established 137 mouse ESC lines, each of which carried a doxycycline-controllable TF. Among them, Sox9 has unique capacity: its forced expression accelerates differentiation of mouse ESCs into cells of all three germ layers. With the additional use of specific culture conditions, overexpression of Sox9 facilitated the generation of endothelial cells, hepatocytes and neurons from ESCs. Furthermore, Sox9 action increases formation of p21 (WAF1/CIP1), which then binds to the SRR2 enhancer of pluripotency marker Sox2 and inhibits its expression. Knockdown of p21 abolishes inhibition of Sox2 and Sox9-accelerated differentiation, and reduction of Sox2 2 days after the beginning of ESC differentiation can comparably accelerate mouse ESC formation of cells of three germ layers. These data implicate the involvement of the p21-Sox2 pathway in the mechanism of accelerated ESC differentiation by Sox9 overexpression. The molecular cascade could be among the first steps to program ESC differentiation.
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Affiliation(s)
- Kohei Yamamizu
- Laboratory of Genetics, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - David Schlessinger
- Laboratory of Genetics, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Minoru S H Ko
- Laboratory of Genetics, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA Department of Systems Medicine, Sakaguchi Laboratory, Keio University School of Medicine, Tokyo 160-8582, Japan
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26
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Okamoto R, Uchikawa M, Kondoh H. Sixteen additional enhancers associated with the chickenSox2locus outside the central 50-kb region. Dev Growth Differ 2014; 57:24-39. [DOI: 10.1111/dgd.12185] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Revised: 09/25/2014] [Accepted: 09/29/2014] [Indexed: 01/06/2023]
Affiliation(s)
- Ryuji Okamoto
- Graduate School of Frontier Biosciences; Osaka University; 1-3 Yamadaoka Suita Osaka 565-0871 Japan
- Faculty of Medicine; Kagawa University; 1750-1 Ikenobe Miki-Cho, Kita-gun Kagawa 761-0793 Japan
| | - Masanori Uchikawa
- Graduate School of Frontier Biosciences; Osaka University; 1-3 Yamadaoka Suita Osaka 565-0871 Japan
| | - Hisato Kondoh
- Graduate School of Frontier Biosciences; Osaka University; 1-3 Yamadaoka Suita Osaka 565-0871 Japan
- Faculty of Life Sciences; Kyoto Sangyo University; Motoyama, Kamigamo Kita-ku Kyoto 603-8555 Japan
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27
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Castaño J, Menendez P, Bruzos-Cidon C, Straccia M, Sousa A, Zabaleta L, Vazquez N, Zubiarrain A, Sonntag KC, Ugedo L, Carvajal-Vergara X, Canals JM, Torrecilla M, Sanchez-Pernaute R, Giorgetti A. Fast and efficient neural conversion of human hematopoietic cells. Stem Cell Reports 2014; 3:1118-31. [PMID: 25458894 PMCID: PMC4264063 DOI: 10.1016/j.stemcr.2014.10.008] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Revised: 10/14/2014] [Accepted: 10/14/2014] [Indexed: 01/15/2023] Open
Abstract
Neurons obtained directly from human somatic cells hold great promise for disease modeling and drug screening. Available protocols rely on overexpression of transcription factors using integrative vectors and are often slow, complex, and inefficient. We report a fast and efficient approach for generating induced neural cells (iNCs) directly from human hematopoietic cells using Sendai virus. Upon SOX2 and c-MYC expression, CD133-positive cord blood cells rapidly adopt a neuroepithelial morphology and exhibit high expansion capacity. Under defined neurogenic culture conditions, they express mature neuronal markers and fire spontaneous action potentials that can be modulated with neurotransmitters. SOX2 and c-MYC are also sufficient to convert peripheral blood mononuclear cells into iNCs. However, the conversion process is less efficient and resulting iNCs have limited expansion capacity and electrophysiological activity upon differentiation. Our study demonstrates rapid and efficient generation of iNCs from hematopoietic cells while underscoring the impact of target cells on conversion efficiency.
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Affiliation(s)
- Julio Castaño
- Josep Carreras Leukemia Research Institute, Cell Therapy Program of the University of Barcelona, Barcelona 08036, Spain
| | - Pablo Menendez
- Josep Carreras Leukemia Research Institute, Cell Therapy Program of the University of Barcelona, Barcelona 08036, Spain; Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona 08010, Spain
| | - Cristina Bruzos-Cidon
- Department of Pharmacology, Faculty of Medicine and Dentistry, University of the Basque Country (UPV/EHU), Leioa 48940, Spain
| | - Marco Straccia
- Department of Cell Biology, Immunology and Neurosciences, Faculty of Medicine, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), University of Barcelona, Barcelona 08036, Spain; Centro de Investigaciones Biomédicas en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Barcelona 08036, Spain
| | - Amaia Sousa
- Laboratory of Stem Cells and Neural Repair, Inbiomed, San Sebastian 20009, Spain
| | - Lorea Zabaleta
- Cell Reprogramming and Differentiation Platform, Inbiomed, San Sebastian 20009, Spain
| | - Nerea Vazquez
- Laboratory of Stem Cells and Neural Repair, Inbiomed, San Sebastian 20009, Spain
| | - Amaia Zubiarrain
- Laboratory of Stem Cells and Neural Repair, Inbiomed, San Sebastian 20009, Spain; Cell Reprogramming and Differentiation Platform, Inbiomed, San Sebastian 20009, Spain
| | - Kai-Christian Sonntag
- Department of Psychiatry, McLean Hospital, Harvard Medical School, Belmont, MA 02478, USA
| | - Luisa Ugedo
- Department of Pharmacology, Faculty of Medicine and Dentistry, University of the Basque Country (UPV/EHU), Leioa 48940, Spain
| | | | - Josep Maria Canals
- Department of Cell Biology, Immunology and Neurosciences, Faculty of Medicine, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), University of Barcelona, Barcelona 08036, Spain; Centro de Investigaciones Biomédicas en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Barcelona 08036, Spain
| | - Maria Torrecilla
- Department of Pharmacology, Faculty of Medicine and Dentistry, University of the Basque Country (UPV/EHU), Leioa 48940, Spain
| | | | - Alessandra Giorgetti
- Josep Carreras Leukemia Research Institute, Cell Therapy Program of the University of Barcelona, Barcelona 08036, Spain.
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28
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Zhang S, Cui W. Sox2, a key factor in the regulation of pluripotency and neural differentiation. World J Stem Cells 2014; 6:305-311. [PMID: 25126380 PMCID: PMC4131272 DOI: 10.4252/wjsc.v6.i3.305] [Citation(s) in RCA: 237] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Revised: 04/07/2014] [Accepted: 05/16/2014] [Indexed: 02/06/2023] Open
Abstract
Sex determining region Y-box 2 (Sox2), a member of the SoxB1 transcription factor family, is an important transcriptional regulator in pluripotent stem cells (PSCs). Together with octamer-binding transcription factor 4 and Nanog, they co-operatively control gene expression in PSCs and maintain their pluripotency. Furthermore, Sox2 plays an essential role in somatic cell reprogramming, reversing the epigenetic configuration of differentiated cells back to a pluripotent embryonic state. In addition to its role in regulation of pluripotency, Sox2 is also a critical factor for directing the differentiation of PSCs to neural progenitors and for maintaining the properties of neural progenitor stem cells. Here, we review recent findings concerning the involvement of Sox2 in pluripotency, somatic cell reprogramming and neural differentiation as well as the molecular mechanisms underlying these roles.
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29
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Gao J, Wang Z, Shao K, Fan L, Yang L, Song H, Liu M, Wang Z, Wang X, Zhang Q. Identification and characterization of a Sox2 homolog in the Japanese flounder Paralichthys olivaceus. Gene 2014; 544:165-76. [DOI: 10.1016/j.gene.2014.04.062] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2013] [Revised: 04/15/2014] [Accepted: 04/20/2014] [Indexed: 12/23/2022]
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30
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Santini R, Pietrobono S, Pandolfi S, Montagnani V, D'Amico M, Penachioni JY, Vinci MC, Borgognoni L, Stecca B. SOX2 regulates self-renewal and tumorigenicity of human melanoma-initiating cells. Oncogene 2014; 33:4697-708. [PMID: 24681955 PMCID: PMC4180644 DOI: 10.1038/onc.2014.71] [Citation(s) in RCA: 158] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Revised: 02/13/2014] [Accepted: 02/17/2014] [Indexed: 02/06/2023]
Abstract
Melanoma is one of the most aggressive types of human cancer, characterized by enhanced heterogeneity and resistance to conventional therapy at advanced stages. We and others have previously shown that HEDGEHOG-GLI (HH-GLI) signaling is required for melanoma growth and for survival and expansion of melanoma-initiating cells (MICs). Recent reports indicate that HH-GLI signaling regulates a set of genes typically expressed in embryonic stem cells, including SOX2 (sex-determining region Y (SRY)-Box2). Here we address the function of SOX2 in human melanomas and MICs and its interaction with HH-GLI signaling. We find that SOX2 is highly expressed in melanoma stem cells. Knockdown of SOX2 sharply decreases self-renewal in melanoma spheres and in putative melanoma stem cells with high aldehyde dehydrogenase activity (ALDH(high)). Conversely, ectopic expression of SOX2 in melanoma cells enhances their self-renewal in vitro. SOX2 silencing also inhibits cell growth and induces apoptosis in melanoma cells. In addition, depletion of SOX2 progressively abrogates tumor growth and leads to a significant decrease in tumor-initiating capability of ALDH(high) MICs upon xenotransplantation, suggesting that SOX2 is required for tumor initiation and for continuous tumor growth. We show that SOX2 is regulated by HH signaling and that the transcription factors GLI1 and GLI2, the downstream effectors of HH-GLI signaling, bind to the proximal promoter region of SOX2 in primary melanoma cells. In functional studies, we find that SOX2 function is required for HH-induced melanoma cell growth and MIC self-renewal in vitro. Thus SOX2 is a critical factor for self-renewal and tumorigenicity of MICs and an important mediator of HH-GLI signaling in melanoma. These findings could provide the basis for novel therapeutic strategies based on the inhibition of SOX2 for the treatment of a subset of human melanomas.
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Affiliation(s)
- R Santini
- Laboratory of Tumor Cell Biology, Core Research Laboratory-Istituto Toscano Tumori (CRL-ITT), Florence, Italy
| | - S Pietrobono
- Laboratory of Tumor Cell Biology, Core Research Laboratory-Istituto Toscano Tumori (CRL-ITT), Florence, Italy
| | - S Pandolfi
- Laboratory of Tumor Cell Biology, Core Research Laboratory-Istituto Toscano Tumori (CRL-ITT), Florence, Italy
| | - V Montagnani
- Laboratory of Tumor Cell Biology, Core Research Laboratory-Istituto Toscano Tumori (CRL-ITT), Florence, Italy
| | - M D'Amico
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - J Y Penachioni
- Laboratory of Tumor Cell Biology, Core Research Laboratory-Istituto Toscano Tumori (CRL-ITT), Florence, Italy
| | - M C Vinci
- Laboratory of Tumor Cell Biology, Core Research Laboratory-Istituto Toscano Tumori (CRL-ITT), Florence, Italy
| | - L Borgognoni
- Plastic Surgery Unit, S.M. Annunziata Hospital-Regional Melanoma Referral Center, Istituto Toscano Tumori, Florence, Italy
| | - B Stecca
- Laboratory of Tumor Cell Biology, Core Research Laboratory-Istituto Toscano Tumori (CRL-ITT), Florence, Italy
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31
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Saritas-Yildirim B, Silva EM. The role of targeted protein degradation in early neural development. Genesis 2014; 52:287-99. [PMID: 24623518 DOI: 10.1002/dvg.22771] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Revised: 03/05/2014] [Accepted: 03/07/2014] [Indexed: 11/08/2022]
Abstract
As neural stem cells differentiate into neurons during neurogenesis, the proteome of the cells is restructured by de novo expression and selective removal of regulatory proteins. The control of neurogenesis at the level of gene regulation is well documented and the regulation of protein abundance through protein degradation via the Ubiquitin/26S proteasome pathway is a rapidly developing field. This review describes our current understanding of the role of the proteasome pathway in neurogenesis. Collectively, the studies show that targeted protein degradation is an important regulatory mechanism in the generation of new neurons.
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32
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Kamachi Y, Kondoh H. Sox proteins: regulators of cell fate specification and differentiation. Development 2013; 140:4129-44. [PMID: 24086078 DOI: 10.1242/dev.091793] [Citation(s) in RCA: 420] [Impact Index Per Article: 38.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Sox transcription factors play widespread roles during development; however, their versatile funtions have a relatively simple basis: the binding of a Sox protein alone to DNA does not elicit transcriptional activation or repression, but requires binding of a partner transcription factor to an adjacent site on the DNA. Thus, the activity of a Sox protein is dependent upon the identity of its partner factor and the context of the DNA sequence to which it binds. In this Primer, we provide an mechanistic overview of how Sox family proteins function, as a paradigm for transcriptional regulation of development involving multi-transcription factor complexes, and we discuss how Sox factors can thus regulate diverse processes during development.
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Affiliation(s)
- Yusuke Kamachi
- Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita, Osaka 565-0871, Japan
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Hu W, Guan FX, Li Y, Tang YJ, Yang F, Yang B. New methods for inducing the differentiation of amniotic-derived mesenchymal stem cells into motor neuron precursor cells. Tissue Cell 2013; 45:295-305. [DOI: 10.1016/j.tice.2013.03.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Revised: 02/23/2013] [Accepted: 03/13/2013] [Indexed: 01/01/2023]
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Characterization of induced neural progenitors from skin fibroblasts by a novel combination of defined factors. Sci Rep 2013; 3:1345. [PMID: 23439431 PMCID: PMC3581826 DOI: 10.1038/srep01345] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2012] [Accepted: 02/12/2013] [Indexed: 12/17/2022] Open
Abstract
Recent reports have demonstrated that somatic cells can be directly converted to other differentiated cell types through ectopic expression of sets of transcription factors, directly avoiding the transition through a pluripotent state. Our previous experiments generated induced neural progenitor-like cells (iNPCs) by a novel combination of five transcription factors (Sox2, Brn2, TLX, Bmi1 and c-Myc). Here we demonstrated that the iNPCs not only possess NPC-specific marker genes, but also have qualities of primary brain-derived NPCs (WT-NPCs), including tripotent differentiation potential, mature neuron differentiation capability and synapse formation. Importantly, the mature neurons derived from iNPCs exhibit significant physiological properties, such as potassium channel activity and generation of action potential-like spikes. These results suggest that directly reprogrammed iNPCs closely resemble WT-NPCs, which may suggest an alternative strategy to overcome the restricted proliferative and lineage potential of induced neurons (iNCs) and broaden applications of cell therapy in the treatment of neurodegenerative disorders.
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Bery A, Martynoga B, Guillemot F, Joly JS, Rétaux S. Characterization of enhancers active in the mouse embryonic cerebral cortex suggests Sox/Pou cis-regulatory logics and heterogeneity of cortical progenitors. Cereb Cortex 2013; 24:2822-34. [PMID: 23720416 DOI: 10.1093/cercor/bht126] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We aimed to identify cis-regulatory elements that control gene expression in progenitors of the cerebral cortex. A list of 975 putative enhancers were retrieved from a ChIP-Seq experiment performed in NS5 mouse stem cells with antibodies to Sox2, Brn2/Pou3f2, or Brn1/Pou3f3. Through a selection pipeline including gene ontology and expression pattern, we reduced the number of candidate enhancer sequences to 20. Ex vivo electroporation of green fluorescent pProtein (GFP) reporter constructs in the telencephalon of mouse embryos showed that 35% of the 20 selected candidate sequences displayed enhancer activity in the developing cortex at E13.5. In silico transcription factor binding site (TFBS) searches and mutagenesis experiments showed that enhancer activity is related to the presence of Sox/Pou TFBS pairs in the sequence. Comparative genomic analyses showed that enhancer activity is not related to the evolutionary conservation of the sequence. Finally, the combination of in utero electroporation of GFP reporter constructs with immunostaining for Tbr2 (basal progenitor marker) and phospho-histoneH3 (mitotic activity marker) demonstrated that each enhancer is specifically active in precise subpopulations of progenitors in the cortical germinal zone, highlighting the heterogeneity of these progenitors in terms of cis-regulation.
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Affiliation(s)
| | | | | | - Jean-Stéphane Joly
- Equipe Morphogenesis of the Chordate Nervous System, UPR3294 N&D, Institut de Neurobiologie Alfred Fessard, CNRS, Gif-sur-Yvette, France and
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SOX2 co-occupies distal enhancer elements with distinct POU factors in ESCs and NPCs to specify cell state. PLoS Genet 2013; 9:e1003288. [PMID: 23437007 PMCID: PMC3578749 DOI: 10.1371/journal.pgen.1003288] [Citation(s) in RCA: 135] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2012] [Accepted: 12/15/2012] [Indexed: 01/26/2023] Open
Abstract
SOX2 is a master regulator of both pluripotent embryonic stem cells (ESCs) and multipotent neural progenitor cells (NPCs); however, we currently lack a detailed understanding of how SOX2 controls these distinct stem cell populations. Here we show by genome-wide analysis that, while SOX2 bound to a distinct set of gene promoters in ESCs and NPCs, the majority of regions coincided with unique distal enhancer elements, important cis-acting regulators of tissue-specific gene expression programs. Notably, SOX2 bound the same consensus DNA motif in both cell types, suggesting that additional factors contribute to target specificity. We found that, similar to its association with OCT4 (Pou5f1) in ESCs, the related POU family member BRN2 (Pou3f2) co-occupied a large set of putative distal enhancers with SOX2 in NPCs. Forced expression of BRN2 in ESCs led to functional recruitment of SOX2 to a subset of NPC-specific targets and to precocious differentiation toward a neural-like state. Further analysis of the bound sequences revealed differences in the distances of SOX and POU peaks in the two cell types and identified motifs for additional transcription factors. Together, these data suggest that SOX2 controls a larger network of genes than previously anticipated through binding of distal enhancers and that transitions in POU partner factors may control tissue-specific transcriptional programs. Our findings have important implications for understanding lineage specification and somatic cell reprogramming, where SOX2, OCT4, and BRN2 have been shown to be key factors. In mammals, a few thousand transcription factors regulate the differential expression of more than 20,000 genes to specify ∼200 functionally distinct cell types during development. How this is accomplished has been a major focus of biology. Transcription factors bind non-coding DNA regulatory elements, including proximal promoters and distal enhancers, to control gene expression. Emerging evidence indicates that transcription factor binding at distal enhancers plays an important role in the establishment of tissue-specific gene expression programs during development. Further, combinatorial binding among groups of transcription factors can further increase the diversity and specificity of regulatory modules. Here, we report the genome-wide binding profile of the HMG-box containing transcription factor SOX2 in mouse embryonic stem cells (ESCs) and neural progenitor cells (NPCs), and we show that SOX2 occupied a distinct set of binding sites with POU homeodomain family members, OCT4 in ESCs and BRN2 in NPCs. Thus, transitions in SOX2-POU partners may control tissue-specific gene networks. Ultimately, a global analysis detailing the combinatorial binding of transcription factors across all tissues is critical to understand cell fate specification in the context of the complex mammalian genome.
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Bolborea M, Dale N. Hypothalamic tanycytes: potential roles in the control of feeding and energy balance. Trends Neurosci 2013; 36:91-100. [PMID: 23332797 PMCID: PMC3605593 DOI: 10.1016/j.tins.2012.12.008] [Citation(s) in RCA: 210] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Revised: 12/11/2012] [Accepted: 12/18/2012] [Indexed: 02/08/2023]
Abstract
Tanycytes, glial-like cells that line the third ventricle, are emerging as components of the hypothalamic networks that control body weight and energy balance. They contact the cerebrospinal fluid (CSF) and send processes that come into close contact with neurons in the arcuate and ventromedial hypothalamic nuclei. Tanycytes are glucosensitive and are able to respond to transmitters associated with arousal and the drive to feed. At least some tanycytes are stem cells and, in the median eminence, may be stimulated by diet to generate new neurons. The quest is on to understand how tanycytes detect and respond to changes in energy balance and how they communicate with the rest of the nervous system to effect their functions.
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Affiliation(s)
- Matei Bolborea
- School of Life Sciences, University of Warwick, Coventry, UK
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38
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Marqués-Torrejón MÁ, Porlan E, Banito A, Gómez-Ibarlucea E, Fernández-Capetillo Ó, Vidal A, Gil J, Torres J, Fariñas I. Cyclin-dependent kinase inhibitor p21 controls adult neural stem cell expansion by regulating Sox2 gene expression. Cell Stem Cell 2013; 12:88-100. [PMID: 23260487 PMCID: PMC3714747 DOI: 10.1016/j.stem.2012.12.001] [Citation(s) in RCA: 153] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2012] [Revised: 10/31/2012] [Accepted: 11/29/2012] [Indexed: 12/26/2022]
Abstract
In the adult brain, continual neurogenesis of olfactory neurons is sustained by the existence of neural stem cells (NSCs) in the subependymal niche. Elimination of the cyclin-dependent kinase inhibitor 1A (p21) leads to premature exhaustion of the subependymal NSC pool, suggesting a relationship between cell cycle control and long-term self-renewal, but the molecular mechanisms underlying NSC maintenance by p21 remain unexplored. Here we identify a function of p21 in the direct regulation of the expression of pluripotency factor Sox2, a key regulator of the specification and maintenance of neural progenitors. We observe that p21 directly binds a Sox2 enhancer and negatively regulates Sox2 expression in NSCs. Augmented levels of Sox2 in p21 null cells induce replicative stress and a DNA damage response that leads to cell growth arrest mediated by increased levels of p19(Arf) and p53. Our results show a regulation of NSC expansion driven by a p21/Sox2/p53 axis.
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Affiliation(s)
- M. Ángeles Marqués-Torrejón
- Departamento de Biología Celular, Universidad de Valencia, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas, Universidad de Valencia, Spain
| | - Eva Porlan
- Departamento de Biología Celular, Universidad de Valencia, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas, Universidad de Valencia, Spain
| | - Ana Banito
- Cell Proliferation Group, MRC Clinical Sciences Centre, Faculty of Medicine, Imperial College, Hammersmith Campus, W12 0NN London, UK
| | - Esther Gómez-Ibarlucea
- Departamento de Fisiología and Centro de Investigación en Medicina Molecular (CIMUS), Instituto de Investigación Sanitaria de Santiago (IDIS), Universidad de Santiago de Compostela, Spain
| | | | - Anxo Vidal
- Departamento de Fisiología and Centro de Investigación en Medicina Molecular (CIMUS), Instituto de Investigación Sanitaria de Santiago (IDIS), Universidad de Santiago de Compostela, Spain
| | - Jesús Gil
- Cell Proliferation Group, MRC Clinical Sciences Centre, Faculty of Medicine, Imperial College, Hammersmith Campus, W12 0NN London, UK
| | - Josema Torres
- Departamento de Biología Celular, Universidad de Valencia, Spain
| | - Isabel Fariñas
- Departamento de Biología Celular, Universidad de Valencia, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas, Universidad de Valencia, Spain
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39
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Kawamata M, Ochiya T. Two distinct knockout approaches highlight a critical role for p53 in rat development. Sci Rep 2012; 2:945. [PMID: 23230510 PMCID: PMC3517977 DOI: 10.1038/srep00945] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2012] [Accepted: 10/29/2012] [Indexed: 01/06/2023] Open
Abstract
Gene targeting in embryonic stem cells (ESCs) has become the principal technology for generating knockout models. Although numerous studies have predicted that the disruption of p53 leads to increased developmental anomalies and malignancies, most p53 knockout mice develop normally. Therefore, the role of p53 in animal development was examined using rat knockout models. Conventionally generated homozygous KO males developed normally, whereas females rarely survived due to neural tube defects. Mutant chimeras generated via blastocyst injection with p53-null ESCs exhibited high rates of embryonic lethality in both sexes. This phenotype could be observed in one month by the use of zinc-finger nucleases. The p53-null ESCs were resistant to apoptosis and differentiation, and exhibited severe chromosome instabilities in the chimera-contributed cells, suggesting an essential role for p53 in maintaining ESC quality and genomic integrity. These results demonstrate that p53 functions as a guardian of embryogenesis in the rats.
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Affiliation(s)
- Masaki Kawamata
- Division of Molecular and Cellular Medicine, National Cancer Center Research Institute , 1-1, Tsukiji, 5-chome, Chuo-ku, Tokyo 104-0045, Japan
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40
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Mandalos N, Saridaki M, Harper JL, Kotsoni A, Yang P, Economides AN, Remboutsika E. Application of a novel strategy of engineering conditional alleles to a single exon gene, Sox2. PLoS One 2012; 7:e45768. [PMID: 23029233 PMCID: PMC3459942 DOI: 10.1371/journal.pone.0045768] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2012] [Accepted: 08/20/2012] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND The Conditional by Inversion (COIN) method for engineering conditional alleles relies on an invertible optimized gene trap-like element, the COIN module, for imparting conditionality. The COIN module contains an optimized 3' splice site-polyadenylation signal pair, but is inserted antisense to the target gene and therefore does not alter transcription, until it is inverted by Cre recombinase. In order to make COIN applicable to all protein-coding genes, the COIN module has been engineered within an artificial intron, enabling insertion into an exon. METHODOLOGY/PRINCIPAL FINDINGS Therefore, theoretically, the COIN method should be applicable to single exon genes, and to test this idea we engineered a COIN allele of Sox2. This single exon gene presents additional design challenges, in that its proximal promoter and coding region are entirely contained within a CpG island, and are also spanned by an overlapping transcript, Sox2Ot, which contains mmu-miR1897. Here, we show that despite disruption of the CpG island by the COIN module intron, the COIN allele of Sox2 (Sox2(COIN)) is phenotypically wild type, and also does not interfere with expression of Sox2Ot and miR1897. Furthermore, the inverted COIN allele of Sox2, Sox2(INV) is functionally null, as homozygotes recapitulate the phenotype of Sox2(βgeo/βgeo) mice, a well-characterized Sox2 null. Lastly, the benefit of the eGFP marker embedded in the COIN allele is demonstrated as it mirrors the expression pattern of Sox2. CONCLUSIONS/SIGNIFICANCE Our results demonstrate the applicability of the COIN technology as a method of choice for targeting single exon genes.
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Affiliation(s)
- Nikolaos Mandalos
- Stem Cell Biology Laboratory, Institute of Molecular Biology and Genetics, Biomedical Sciences Research Centre “Alexander Fleming”, Vari, Greece
| | - Marannia Saridaki
- Stem Cell Biology Laboratory, Institute of Molecular Biology and Genetics, Biomedical Sciences Research Centre “Alexander Fleming”, Vari, Greece
| | - Jessica Lea Harper
- Stem Cell Biology Laboratory, Institute of Molecular Biology and Genetics, Biomedical Sciences Research Centre “Alexander Fleming”, Vari, Greece
- Regeneron Pharmaceuticals Inc., Tarrytown, New York, United States of America
| | - Anastasia Kotsoni
- Stem Cell Biology Laboratory, Institute of Molecular Biology and Genetics, Biomedical Sciences Research Centre “Alexander Fleming”, Vari, Greece
| | - Peter Yang
- Regeneron Pharmaceuticals Inc., Tarrytown, New York, United States of America
| | - Aris N. Economides
- Regeneron Pharmaceuticals Inc., Tarrytown, New York, United States of America
| | - Eumorphia Remboutsika
- Stem Cell Biology Laboratory, Institute of Molecular Biology and Genetics, Biomedical Sciences Research Centre “Alexander Fleming”, Vari, Greece
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López-Juárez A, Remaud S, Hassani Z, Jolivet P, Pierre Simons J, Sontag T, Yoshikawa K, Price J, Morvan-Dubois G, Demeneix BA. Thyroid hormone signaling acts as a neurogenic switch by repressing Sox2 in the adult neural stem cell niche. Cell Stem Cell 2012; 10:531-43. [PMID: 22560077 DOI: 10.1016/j.stem.2012.04.008] [Citation(s) in RCA: 101] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2010] [Revised: 01/12/2012] [Accepted: 04/09/2012] [Indexed: 02/02/2023]
Abstract
The subventricular zone (SVZ) neural stem cell niche contains mixed populations of stem cells, transit-amplifying cells, and migrating neuroblasts. Deciphering how endogenous signals, such as hormones, affect the balance between these cell types is essential for understanding the physiology of niche plasticity and homeostasis. We show that Thyroid Hormone (T(3)) and its receptor, TRα1, are directly involved in maintaining this balance. TRα1 is expressed in amplifying and migrating cells. In vivo gain- and loss-of-function experiments demonstrate first, that T(3)/TRα1 directly repress Sox2 expression, and second, that TRα1 overexpression in the niche favors the appearance of DCX+ migrating neuroblasts. Lack of TRα increases numbers of SOX2+ cells in the SVZ. Hypothyroidism increases proportions of cells in interphase. Thus, in the adult SVZ, T(3)/TRα1 together favor neural stem cell commitment and progression toward a migrating neuroblast phenotype; this transition correlates with T(3)/TRα1-dependent transcriptional repression of Sox2.
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Affiliation(s)
- Alejandra López-Juárez
- UMR CNRS 7221, Evolution des Régulations Endocriniennes, Département Régulations, Développement et Diversité Moléculaire, Muséum National d'Histoire Naturelle, 75231 Paris, France
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The co-transduction of Nurr1 and Brn4 genes induces the differentiation of neural stem cells into dopaminergic neurons. Cell Biol Int 2012; 35:1217-23. [PMID: 21663595 DOI: 10.1042/cbi20110028] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Fetal brain tissue can be used in cell replacement therapy for PD (Parkinson's disease), but there is a poor donor supply of this tissue. NSCs (neural stem cells) may overcome this problem as they can be isolated and expanded in vitro. However, the usage of NSCs is limited because the differentiation of NSCs into specific dopaminergic neurons has proven difficult. In the present study, we investigated the effect of Nurr1 (nuclear receptor related factor 1), a transcription factor specific for the development and maintenance of the midbrain dopaminergic neurons on inducing the differentiation of NSCs into TH (tyrosine hydroxylase) immunoreactive dopaminergic neurons. Nonetheless, these cells exhibited an immature neuronal morphology with small cell bodies and short neurite processes, and they seldom expressed DAT (dopamine transporter), a late marker of mature dopaminergic neurons. However, forced co-expression of Nurr1 with Brn4, a member of the POU domain family of transcription factors, caused immature Nurr1-induced dopaminergic neurons to differentiate into morphologically and phenotypically more mature neurons. Thus the enriched generation of mature dopaminergic neurons by forced expression of Nurr1 with Brn4 may be of future importance in NSC-based cell replacement therapy for PD.
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43
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Tian C, Ambroz RJ, Sun L, Wang Y, Ma K, Chen Q, Zhu B, Zheng JC. Direct conversion of dermal fibroblasts into neural progenitor cells by a novel cocktail of defined factors. Curr Mol Med 2012; 12:126-37. [PMID: 22172100 DOI: 10.2174/156652412798889018] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2011] [Revised: 11/17/2011] [Accepted: 11/23/2011] [Indexed: 12/15/2022]
Abstract
The generation of functional neural progenitor cells (NPCs) independent of donor brain tissue and embryonic tissues is of great therapeutic interest with regard to regenerative medicine and the possible treatment of neurodegenerative disorders. Traditionally, NPCs are derived through the differentiation of embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs). However, the induction of NPCs from ESCs and iPSCs is a complicated process that increases the risk of neoplasia and undesired cell types. This process can be circumvented through the direct conversion of somatic cells from one cell type to another by ectopic expression of specifically defined transcription factors. Using gene expression profiling and parental cells from E/Nestin:EGFP transgenic mice as a monitoring system, we tested nine factors with the potential to directly convert fibroblasts into NPCs. We found that five of these factors can directly convert adult dermal fibroblasts into NPC-like cells (iNPCs), and the resulting iNPCs possessed similar properties as primary NPCs including proliferation, self-renewal and differentiation. Significantly, iNPCs also exhibit chemotactic properties similar to those of primary NPCs. These provide an important alternative strategy to generate iNPCs for cell replacement therapy of neurodegenerative diseases.
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Affiliation(s)
- C Tian
- Laboratory of Neuroimmunology and Regenerative Therapy, University of Nebraska Medical Center, Omaha, NE 68198-5930, USA.
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44
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SOX2 hypomorphism disrupts development of the prechordal floor and optic cup. Mech Dev 2012; 129:1-12. [PMID: 22522080 DOI: 10.1016/j.mod.2012.04.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Accepted: 04/04/2012] [Indexed: 12/19/2022]
Abstract
Haploinsufficiency for the HMG-box transcription factor SOX2 results in abnormalities of the human ventral forebrain and its derivative structures. These defects include anophthalmia (absence of eye), microphthalmia (small eye) and hypothalamic hamartoma (HH), an overgrowth of the ventral hypothalamus. To determine how Sox2 deficiency affects the morphogenesis of the ventral diencephalon and eye, we generated a Sox2 allelic series (Sox2(IR), Sox2(LP), and Sox2(EGFP)), allowing for the generation of mice that express germline hypomorphic levels (<40%) of SOX2 protein and that faithfully recapitulate SOX2 haploinsufficient human phenotypes. We find that Sox2 hypomorphism significantly disrupts the development of the posterior hypothalamus, resulting in an ectopic protuberance of the prechordal floor, an upregulation of Shh signaling, and abnormal hypothalamic patterning. In the anterior diencephalon, both the optic stalks and optic cups (OC) of Sox2 hypomorphic (Sox2(HYP)) embryos are malformed. Furthermore, Sox2(HYP) eyes exhibit a loss of neural potential and coloboma, a common phenotype in SOX2 haploinsufficient humans that has not been described in a mouse model of SOX2 deficiency. These results establish for the first time that germline Sox2 hypomorphism disrupts the morphogenesis and patterning of the hypothalamus, optic stalk, and the early OC, establishing a model of the development of the abnormalities that are observed in SOX2 haploinsufficient humans.
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45
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Mariani J, Favaro R, Lancini C, Vaccari G, Ferri AL, Bertolini J, Tonoli D, Latorre E, Caccia R, Ronchi A, Ottolenghi S, Miyagi S, Okuda A, Zappavigna V, Nicolis SK. Emx2 is a dose-dependent negative regulator of Sox2 telencephalic enhancers. Nucleic Acids Res 2012; 40:6461-76. [PMID: 22495934 PMCID: PMC3413107 DOI: 10.1093/nar/gks295] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
The transcription factor Sox2 is essential for neural stem cells (NSC) maintenance in the hippocampus and in vitro. The transcription factor Emx2 is also critical for hippocampal development and NSC self-renewal. Searching for ‘modifier’ genes affecting the Sox2 deficiency phenotype in mouse, we observed that loss of one Emx2 allele substantially increased the telencephalic β-geo (LacZ) expression of a transgene driven by the 5′ or 3′ Sox2 enhancer. Reciprocally, Emx2 overexpression in NSC cultures inhibited the activity of the same transgene. In vivo, loss of one Emx2 allele increased Sox2 levels in the medial telencephalic wall, including the hippocampal primordium. In hypomorphic Sox2 mutants, retaining a single ‘weak’ Sox2 allele, Emx2 deficiency substantially rescued hippocampal radial glia stem cells and neurogenesis, indicating that Emx2 functionally interacts with Sox2 at the stem cell level. Electrophoresis mobility shift assays and transfection indicated that Emx2 represses the activities of both Sox2 enhancers. Emx2 bound to overlapping Emx2/POU-binding sites, preventing binding of the POU transcriptional activator Brn2. Additionally, Emx2 directly interacted with Brn2 without binding to DNA. These data imply that Emx2 may perform part of its functions by negatively modulating Sox2 in specific brain areas, thus controlling important aspects of NSC function in development.
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Affiliation(s)
- J Mariani
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, 20126 Milano, Italy
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46
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Pluripotency factors in embryonic stem cells regulate differentiation into germ layers. Cell 2011; 145:875-89. [PMID: 21663792 DOI: 10.1016/j.cell.2011.05.017] [Citation(s) in RCA: 403] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2010] [Revised: 03/03/2011] [Accepted: 05/16/2011] [Indexed: 02/06/2023]
Abstract
Cell fate decisions are fundamental for development, but we do not know how transcriptional networks reorganize during the transition from a pluripotent to a differentiated cell state. Here, we asked how mouse embryonic stem cells (ESCs) leave the pluripotent state and choose between germ layer fates. By analyzing the dynamics of the transcriptional circuit that maintains pluripotency, we found that Oct4 and Sox2, proteins that maintain ESC identity, also orchestrate germ layer fate selection. Oct4 suppresses neural ectodermal differentiation and promotes mesendodermal differentiation; Sox2 inhibits mesendodermal differentiation and promotes neural ectodermal differentiation. Differentiation signals continuously and asymmetrically modulate Oct4 and Sox2 protein levels, altering their binding pattern in the genome, and leading to cell fate choice. The same factors that maintain pluripotency thus also integrate external signals and control lineage selection. Our study provides a framework for understanding how complex transcription factor networks control cell fate decisions in progenitor cells.
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Abstract
The cancer stem cell (CSC) model does not imply that tumours are generated from transformed tissue stem cells. The target of transformation could be a tissue stem cell, a progenitor cell, or a differentiated cell that acquires self-renewal ability. The observation that induced pluripotency reprogramming and cancer are related has lead to the speculation that CSCs may arise through a reprogramming-like mechanism. Expression of pluripotency genes (Oct4, Nanog and Sox2) was tested in breast tumours by immunohistochemistry and it was found that Sox2 is expressed in early stage breast tumours. However, expression of Oct4 or Nanog was not found. Mammosphere formation in culture was used to reveal stem cell properties, where expression of Sox2, but not Oct4 or Nanog, was induced. Over-expression of Sox2 increased mammosphere formation, effect dependent on continuous Sox2 expression; furthermore, Sox2 knockdown prevented mammosphere formation and delayed tumour formation in xenograft tumour initiation models. Induction of Sox2 expression was achieved through activation of the distal enhancer of Sox2 promoter upon sphere formation, the same element that controls Sox2 transcription in pluripotent stem cells. These findings suggest that reactivation of Sox2 represents an early step in breast tumour initiation, explaining tumour heterogeneity by placing the tumour-initiating event in any cell along the axis of mammary differentiation.
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48
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Dhaliwal J, Lagace DC. Visualization and genetic manipulation of adult neurogenesis using transgenic mice. Eur J Neurosci 2011; 33:1025-36. [PMID: 21395845 DOI: 10.1111/j.1460-9568.2011.07600.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Many laboratories have focused efforts on the creation of transgenic mouse models to study adult neurogenesis. In the last decade several constitutive reporter, as well as inducible transgenic lines have been published that allowed for visualization, tracking and alteration of specific neurogenic cell populations in the adult brain. Given the popularity of this approach, multiple mouse lines are available, and this review summarizes the differences in the basic techniques that have been used to create these mice, highlighting the different constructs and reporter proteins used, as well as the strengths and limitations of each of these models. Representative examples from the literature demonstrate some of the diverse and seminal findings that have come to fruition through the laborious, yet highly rewarding work of creating transgenic mouse lines for adult neurogenesis research.
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Affiliation(s)
- Jagroop Dhaliwal
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
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49
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Iwafuchi-Doi M, Yoshida Y, Onichtchouk D, Leichsenring M, Driever W, Takemoto T, Uchikawa M, Kamachi Y, Kondoh H. The Pou5f1/Pou3f-dependent but SoxB-independent regulation of conserved enhancer N2 initiates Sox2 expression during epiblast to neural plate stages in vertebrates. Dev Biol 2010; 352:354-66. [PMID: 21185279 DOI: 10.1016/j.ydbio.2010.12.027] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2010] [Revised: 12/09/2010] [Accepted: 12/16/2010] [Indexed: 12/30/2022]
Abstract
The transcription factor Sox2 is a core component of the pluripotency control circuits in the early embryo, and later controls many aspects of neural development. Here, we demonstrate that Sox2 expression in the epiblast (mouse blastoderm) and anterior neural plate (ANP) is determined by the upstream enhancer N2. The mouse enhancer N2 exhibits strong activity in mouse ES cells, epiblast and ANP, and is regulated correctly in chicken and zebrafish embryos. Targeted deletion of this enhancer in mouse embryos caused a large reduction of Sox2 expression to 10% of that of wild-type levels in epiblast and ANP. However, this was tolerated by mouse embryo, probably due to functional compensation by Sox3. The activity of enhancer N2 depends on phylogenetically conserved bipartite POU factor-binding motifs in a 73-bp core sequence that function synergistically, but this activation does not involve Sox2. The major POU factor expressed at the epiblastic stage is Pou5f1 (Oct3/4), while those in the anterior neural plate are Pou3f factors (Oct6, Brn2 etc.). These factors are gradually exchanged during the transition from epiblast to ANP stages in mouse embryos and epiblast stem cells (EpiSC). Consistently, enhancer N2 activity changes from full Pou5f1 dependence to Pou3f dependence during the development of neural plate cells (NPC) from EpiSC, as assessed by specific POU factor knockdown in these cells. Zebrafish mutant embryos completely devoid of Pou5f1 activity failed to activate enhancer N2 and to express Sox2 in the blastoderm and ANP, and these defects were rescued by exogenous supply of pou5f1. Previously, Pou5f1-Sox2 synergism-dependent Sox2 activation through enhancer SRR2 in ES cells has been highlighted, but this mechanism is limited to ES cells and amniotes. In contrast, the enhancer N2-mediated, POU factor-dependent activation of Sox2, without involvement of Sox2, is a phylogenetically conserved core mechanism that functions in gene regulatory networks at early embryonic stages.
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Affiliation(s)
- Makiko Iwafuchi-Doi
- Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita, Osaka 565-0871, Japan
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Peltier J, Conway A, Keung AJ, Schaffer DV. Akt increases sox2 expression in adult hippocampal neural progenitor cells, but increased sox2 does not promote proliferation. Stem Cells Dev 2010; 20:1153-61. [PMID: 21028992 DOI: 10.1089/scd.2010.0130] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Multiple extracellular factors have been shown to modulate adult hippocampal neural progenitor cell (NPC) proliferation and self-renewal, and we have previously shown that Akt is an important mediator of the effects of these extracellular factors on NPC proliferation and differentiation. However, very little work has investigated how and whether Akt is involved in maintaining the multipotency of these cells. Here we demonstrate that Akt promotes expression of Sox2, a core transcription factor important for the self-renewal of NPCs. Retroviral-mediated overexpression of wild-type Akt increased Sox2 protein expression, particularly under conditions that promote cell differentiation, whereas Akt inhibition decreased Sox2. Similarly, quantitative reverse transcription (RT)-PCR in differentiating cultures indicated that Akt rescued Sox2 mRNA to levels present under conditions that promote cell proliferation. Additionally, pharmacological inhibition of Akt did not affect Sox2 protein levels in cells constitutively expressing Sox2 from a retroviral vector, indicating that Akt does not affect Sox2 protein stability. Further, in contrast to Akt overexpression, Sox2 overexpression does not increase NPC viable cell number or proliferation yet does inhibit differentiation. Collectively, these results indicate that Akt promotes cell proliferation and maintenance of a multipotent state via two downstream paths.
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Affiliation(s)
- Joseph Peltier
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720-3220, USA
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