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Hongo I, Yamaguchi C, Okamoto H. Brain enlargement with rostral bias in larvae from a spontaneously occurring female variant line of Xenopus; role of aberrant embryonic Wnt/β-catenin signaling. Cells Dev 2024:203918. [PMID: 38574816 DOI: 10.1016/j.cdev.2024.203918] [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: 02/01/2024] [Revised: 03/11/2024] [Accepted: 03/29/2024] [Indexed: 04/06/2024]
Abstract
Increased brain size and its rostral bias are hallmarks of vertebrate evolution, but the underlying developmental and genetic basis remains poorly understood. To provide clues to understanding vertebrate brain evolution, we investigated the developmental mechanisms of brain enlargement observed in the offspring of a previously unrecognized, spontaneously occurring female variant line of Xenopus that appears to reflect a genetic variation. Brain enlargement in larvae from this line showed a pronounced rostral bias that could be traced back to the neural plate, the primordium of the brain. At the gastrula stage, the Spemann organizer, which is known to induce the neural plate from the adjacent dorsal ectoderm and give it the initial rostrocaudal patterning, was expanded from dorsal to ventral in a large proportion of the offspring of variant females. Consistently, siamois expression, which is required for Spemann organizer formation, was expanded laterally from dorsal to ventral at the blastula stage in variant offspring. This implies that the active region of the Wnt/β-catenin signaling pathway was similarly expanded in advance on the dorsal side, as siamois is a target gene of this pathway. Notably, the earliest detectable change in variant offspring was in fertilized eggs, in which maternal wnt11b mRNA, a candidate dorsalizing factor responsible for activating Wnt/β-catenin signaling in the dorsal embryonic region, had a wider distribution in the vegetal cortical cytoplasm. Since lateral spreading of wnt11b mRNA, and possibly that of other potential maternal dorsalizing factors in these eggs, is expected to facilitate lateral expansion of the active region of the Wnt/β-catenin pathway during subsequent embryonic stages, we concluded that aberrant Wnt/β-catenin signaling could cause rostral-biased brain enlargement via expansion of siamois expression and consequent expansion of the Spemann organizer in Xenopus. Our studies of spontaneously occurring variations in brain development in Xenopus would provide hints for uncovering genetic mutations that drive analogous morphogenetic variations during vertebrate brain evolution.
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Affiliation(s)
- Ikuko Hongo
- Department of Life Science, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo 171-8588, Japan
| | - Chihiro Yamaguchi
- Department of Life Science, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo 171-8588, Japan
| | - Harumasa Okamoto
- Department of Life Science, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo 171-8588, Japan.
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2
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Asashima M, Satou-Kobayashi Y. Spemann-Mangold organizer and mesoderm induction. Cells Dev 2024:203903. [PMID: 38295873 DOI: 10.1016/j.cdev.2024.203903] [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: 11/13/2023] [Revised: 01/23/2024] [Accepted: 01/24/2024] [Indexed: 02/09/2024]
Abstract
The discovery of the Spemann-Mangold organizer strongly influenced subsequent research on embryonic induction, with research aiming to elucidate the molecular characteristics of organizer activity being currently underway. Herein, we review the history of research on embryonic induction, and describe how the mechanisms of induction phenomena and developmental processes have been investigated. Classical experiments investigating the differentiation capacity and inductive activity of various embryonic regions were conducted by many researchers, and important theories of region-specific induction and the concept for chain of induction were proposed. The transition from experimental embryology to developmental biology has enabled us to understand the mechanisms of embryonic induction at the molecular level. Consequently, many inducing substances and molecules such as transcriptional factors and peptide growth factors involved in the organizer formation were identified. One of peptide growth factors, activin, acts as a mesoderm- and endoderm-inducing substance. Activin induces several tissues and organs from the undifferentiated cell mass of amphibian embryos in a concentration-dependent manner. We review the extent to which we can control in vitro organogenesis from undifferentiated cells, and discuss the application to stem cell-based regenerative medicine based on insights gained from animal experiments, such as in amphibians.
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Affiliation(s)
- Makoto Asashima
- Advanced Comprehensive Research Organization, Teikyo University, 2-11-1 Kaga, Itabashi-ku, Tokyo 173-0003, Japan.
| | - Yumeko Satou-Kobayashi
- Advanced Comprehensive Research Organization, Teikyo University, 2-11-1 Kaga, Itabashi-ku, Tokyo 173-0003, Japan
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3
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Iqbal Z, Xia J, Murtaza G, Shabbir M, Rehman K, Yujie L, Duan L. Targeting WNT signalling pathways as new therapeutic strategies for osteoarthritis. J Drug Target 2023; 31:1027-1049. [PMID: 37969105 DOI: 10.1080/1061186x.2023.2281861] [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: 06/20/2023] [Accepted: 10/21/2023] [Indexed: 11/17/2023]
Abstract
Osteoarthritis (OA) is a highly prevalent chronic joint disease and the leading cause of disability. Currently, no drugs are available to control joint damage or ease the associated pain. The wingless-type (WNT) signalling pathway is vital in OA progression. Excessive activation of the WNT signalling pathway is pertinent to OA progression and severity. Therefore, agonists and antagonists of the WNT pathway are considered potential drug candidates for OA treatment. For example, SM04690, a novel small molecule inhibitor of WNT signalling, has demonstrated its potential in a recent phase III clinical trial as a disease-modifying osteoarthritis drug (DMOAD). Therefore, targeting the WNT signalling pathway may be a distinctive approach to developing particular agents helpful in treating OA. This review aims to update the most recent progress in OA drug development by targeting the WNT pathway. In this, we introduce WNT pathways and their crosstalk with other signalling pathways in OA development and highlight the role of the WNT signalling pathway as a key regulator in OA development. Several articles have reviewed the Wnt pathway from different aspects. This candid review provides an introduction to WNT pathways and their crosstalk with other signalling pathways in OA development, highlighting the role of the WNT signalling pathway as a key regulator in OA development with the latest research. Particularly, we emphasise the state-of-the-art in targeting the WNT pathway as a promising therapeutic approach for OA and challenges in their development and the nanocarrier-based delivery of WNT modulators for treating OA.
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Affiliation(s)
- Zoya Iqbal
- Department of Orthopedics, The First Affiliated Hospital of Shenzhen University, Shenzhen Second People's Hospital, Shenzhen, Guangdong, China
- Guangdong Provincial Research Center for Artificial Intelligence and Digital Orthopedic Technology, Shenzhen Second People's Hospital, Shenzhen, Guangdong, China
| | - Jiang Xia
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China
| | - Ghulam Murtaza
- Department of Pharmacy, COMSATS University Islamabad, Lahore Campus, Pakistan
| | - Maryam Shabbir
- Faculty of Pharmacy, The University of Lahore, Lahore Campus, Pakistan
| | - Khurrum Rehman
- Department of Allied health sciences, The University of Agriculture, D.I.Khan, Pakistan
| | - Liang Yujie
- Affiliated Hospital of Jining Medical University, Jining, Shandong, China
| | - Li Duan
- Department of Orthopedics, The First Affiliated Hospital of Shenzhen University, Shenzhen Second People's Hospital, Shenzhen, Guangdong, China
- Guangdong Provincial Research Center for Artificial Intelligence and Digital Orthopedic Technology, Shenzhen Second People's Hospital, Shenzhen, Guangdong, China
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4
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Šimková K, Naraine R, Vintr J, Soukup V, Šindelka R. RNA localization during early development of the axolotl. Front Cell Dev Biol 2023; 11:1260795. [PMID: 37928901 PMCID: PMC10620976 DOI: 10.3389/fcell.2023.1260795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Accepted: 09/26/2023] [Indexed: 11/07/2023] Open
Abstract
The asymmetric localization of biomolecules is critical for body plan development. One of the most popular model organisms for early embryogenesis studies is Xenopus laevis but there is a lack of information in other animal species. Here, we compared the early development of two amphibian species-the frog X. laevis and the axolotl Ambystoma mexicanum. This study aimed to identify asymmetrically localized RNAs along the animal-vegetal axis during the early development of A. mexicanum. For that purpose, we performed spatial transcriptome-wide analysis at low resolution, which revealed dynamic changes along the animal-vegetal axis classified into the following categories: profile alteration, de novo synthesis and degradation. Surprisingly, our results showed that many of the vegetally localized genes, which are important for germ cell development, are degraded during early development. Furthermore, we assessed the motif presence in UTRs of degraded mRNAs and revealed the enrichment of several motifs in RNAs of germ cell markers. Our results suggest novel reorganization of the transcriptome during embryogenesis of A. mexicanum to converge to the similar developmental pattern as the X. laevis.
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Affiliation(s)
- Kateřina Šimková
- Laboratory of Gene Expression, Institute of Biotechnology of the Czech Academy of Sciences, Vestec, Czechia
| | - Ravindra Naraine
- Laboratory of Gene Expression, Institute of Biotechnology of the Czech Academy of Sciences, Vestec, Czechia
| | - Jan Vintr
- Department of Zoology, Faculty of Science, Charles University, Prague, Czechia
| | - Vladimír Soukup
- Department of Zoology, Faculty of Science, Charles University, Prague, Czechia
| | - Radek Šindelka
- Laboratory of Gene Expression, Institute of Biotechnology of the Czech Academy of Sciences, Vestec, Czechia
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5
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Gao J, Lu Y, Luo Y, Duan X, Chen P, Zhang X, Wu X, Qiu M, Shen W. β-Catenin and SOX2 Interaction Regulate Visual Experience-Dependent Cell Homeostasis in the Developing Xenopus Thalamus. Int J Mol Sci 2023; 24:13593. [PMID: 37686400 PMCID: PMC10488257 DOI: 10.3390/ijms241713593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 08/19/2023] [Accepted: 08/30/2023] [Indexed: 09/10/2023] Open
Abstract
In the vertebrate brain, sensory experience plays a crucial role in shaping thalamocortical connections for visual processing. However, it is still not clear how visual experience influences tissue homeostasis and neurogenesis in the developing thalamus. Here, we reported that the majority of SOX2-positive cells in the thalamus are differentiated neurons that receive visual inputs as early as stage 47 Xenopus. Visual deprivation (VD) for 2 days shifts the neurogenic balance toward proliferation at the expense of differentiation, which is accompanied by a reduction in nuclear-accumulated β-catenin in SOX2-positive neurons. The knockdown of β-catenin decreases the expression of SOX2 and increases the number of progenitor cells. Coimmunoprecipitation studies reveal the evolutionary conservation of strong interactions between β-catenin and SOX2. These findings indicate that β-catenin interacts with SOX2 to maintain homeostatic neurogenesis during thalamus development.
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Affiliation(s)
- Juanmei Gao
- Zhejiang Key Laboratory of Organ Development and Regeneration, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China (M.Q.)
- College of Life and Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yufang Lu
- Zhejiang Key Laboratory of Organ Development and Regeneration, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China (M.Q.)
| | - Yuhao Luo
- Zhejiang Key Laboratory of Organ Development and Regeneration, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China (M.Q.)
| | - Xinyi Duan
- Zhejiang Key Laboratory of Organ Development and Regeneration, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China (M.Q.)
| | - Peiyao Chen
- Zhejiang Key Laboratory of Organ Development and Regeneration, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China (M.Q.)
| | - Xinyu Zhang
- Zhejiang Key Laboratory of Organ Development and Regeneration, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China (M.Q.)
| | - Xiaohua Wu
- Zhejiang Key Laboratory of Organ Development and Regeneration, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China (M.Q.)
| | - Mengsheng Qiu
- Zhejiang Key Laboratory of Organ Development and Regeneration, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China (M.Q.)
- College of Life and Sciences, Zhejiang University, Hangzhou 310058, China
| | - Wanhua Shen
- Zhejiang Key Laboratory of Organ Development and Regeneration, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China (M.Q.)
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6
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Söderholm S, Jauregi-Miguel A, Pagella P, Ghezzi V, Zambanini G, Nordin A, Cantù C. Single-cell response to Wnt signaling activation reveals uncoupling of Wnt target gene expression. Exp Cell Res 2023:113646. [PMID: 37271249 DOI: 10.1016/j.yexcr.2023.113646] [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: 12/21/2022] [Revised: 05/09/2023] [Accepted: 05/14/2023] [Indexed: 06/06/2023]
Abstract
Wnt signaling drives nuclear translocation of β-catenin and its subsequent association with the DNA-bound TCF/LEF transcription factors, which dictate target gene specificity by recognizing Wnt responsive elements across the genome. β-Catenin target genes are therefore thought to be collectively activated upon Wnt pathway stimulation. However, this appears in contrast with the non-overlapping patterns of Wnt target gene expression in several contexts, including early mammalian embryogenesis. Here we followed Wnt target gene expression in human embryonic stem cells after Wnt pathway stimulation at a single-cell resolution. Cells changed gene expression program over time consistent with three key developmental events: i) loss of pluripotency, ii) induction of Wnt target genes, and iii) mesoderm specification. Contrary to our expectation, not all cells displayed equal amplitude of Wnt target gene activation; rather, they distributed in a continuum from strong to weak responders when ranked based on the expression of the target AXIN2. Moreover, high AXIN2 did not always correspond to elevated expression of other Wnt targets, which were activated in different proportions in individual cells. The uncoupling of Wnt target gene expression was also identified in single cell transcriptomics profiling of other Wnt-responding cell types, including HEK293T, murine developing forelimbs, and human colorectal cancer. Our finding underlines the necessity to identify additional mechanisms that explain the heterogeneity of the Wnt/β-catenin-mediated transcriptional outputs in single cells.
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Affiliation(s)
- Simon Söderholm
- Wallenberg Centre for Molecular Medicine, Linköping University, Linköping, Sweden; Department of Biomedical and Clinical Sciences, Division of Molecular Medicine and Virology, Faculty of Medicine and Health Sciences, Linköping University, Linköping, Sweden
| | - Amaia Jauregi-Miguel
- Wallenberg Centre for Molecular Medicine, Linköping University, Linköping, Sweden; Department of Biomedical and Clinical Sciences, Division of Molecular Medicine and Virology, Faculty of Medicine and Health Sciences, Linköping University, Linköping, Sweden
| | - Pierfrancesco Pagella
- Wallenberg Centre for Molecular Medicine, Linköping University, Linköping, Sweden; Department of Biomedical and Clinical Sciences, Division of Molecular Medicine and Virology, Faculty of Medicine and Health Sciences, Linköping University, Linköping, Sweden
| | - Valeria Ghezzi
- Wallenberg Centre for Molecular Medicine, Linköping University, Linköping, Sweden; Department of Biomedical and Clinical Sciences, Division of Molecular Medicine and Virology, Faculty of Medicine and Health Sciences, Linköping University, Linköping, Sweden
| | - Gianluca Zambanini
- Wallenberg Centre for Molecular Medicine, Linköping University, Linköping, Sweden; Department of Biomedical and Clinical Sciences, Division of Molecular Medicine and Virology, Faculty of Medicine and Health Sciences, Linköping University, Linköping, Sweden
| | - Anna Nordin
- Wallenberg Centre for Molecular Medicine, Linköping University, Linköping, Sweden; Department of Biomedical and Clinical Sciences, Division of Molecular Medicine and Virology, Faculty of Medicine and Health Sciences, Linköping University, Linköping, Sweden
| | - Claudio Cantù
- Wallenberg Centre for Molecular Medicine, Linköping University, Linköping, Sweden; Department of Biomedical and Clinical Sciences, Division of Molecular Medicine and Virology, Faculty of Medicine and Health Sciences, Linköping University, Linköping, Sweden.
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7
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Zinina VV, Sauer M, Nigmatullina L, Kreim N, Soshnikova N. TCF7L1 Controls the Differentiation of Tuft Cells in Mouse Small Intestine. Cells 2023; 12:1452. [PMID: 37296573 PMCID: PMC10253002 DOI: 10.3390/cells12111452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 05/10/2023] [Accepted: 05/18/2023] [Indexed: 06/12/2023] Open
Abstract
Continuous and rapid renewal of the intestinal epithelium depends on intestinal stem cells (ISCs). A large repertoire of transcription factors mediates the correct maintenance and differentiation of ISCs along either absorptive or secretory lineages. In the present study, we addressed the role of TCF7L1, a negative regulator of WNT signalling, in embryonic and adult intestinal epithelium using conditional mouse mutants. We found that TCF7L1 prevents precocious differentiation of the embryonic intestinal epithelial progenitors towards enterocytes and ISCs. We show that Tcf7l1 deficiency leads to upregulation of the Notch effector Rbp-J, resulting in a subsequent loss of embryonic secretory progenitors. In the adult small intestine, TCF7L1 is required for the differentiation of secretory epithelial progenitors along the tuft cell lineage. Furthermore, we show that Tcf7l1 promotes the differentiation of enteroendocrine D- and L-cells in the anterior small intestine. We conclude that TCF7L1-mediated repression of both Notch and WNT pathways is essential for the correct differentiation of intestinal secretory progenitors.
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Affiliation(s)
- Valeriya V. Zinina
- Institute for Molecular Medicine, University Medical Center of the Johannes Gutenberg-University, 55131 Mainz, Germany; (V.V.Z.); (M.S.)
| | - Melanie Sauer
- Institute for Molecular Medicine, University Medical Center of the Johannes Gutenberg-University, 55131 Mainz, Germany; (V.V.Z.); (M.S.)
| | | | - Nastasja Kreim
- Institute of Molecular Biology gGmbH, 55128 Mainz, Germany (N.K.)
| | - Natalia Soshnikova
- Institute for Molecular Medicine and Research Center for Immunotherapy (FZI), University Medical Center of the Johannes Gutenberg-University, 55131 Mainz, Germany
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8
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Predes D, Maia LA, Matias I, Araujo HPM, Soares C, Barros-Aragão FGQ, Oliveira LFS, Reis RR, Amado NG, Simas ABC, Mendes FA, Gomes FCA, Figueiredo CP, Abreu JG. The Flavonol Quercitrin Hinders GSK3 Activity and Potentiates the Wnt/β-Catenin Signaling Pathway. Int J Mol Sci 2022; 23:ijms232012078. [PMID: 36292931 PMCID: PMC9602613 DOI: 10.3390/ijms232012078] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 09/09/2022] [Accepted: 09/10/2022] [Indexed: 11/23/2022] Open
Abstract
The Wnt/β-catenin signaling pathway dictates cell proliferation and differentiation during embryonic development and tissue homeostasis. Its deregulation is associated with many pathological conditions, including neurodegenerative disease, frequently downregulated. The lack of efficient treatment for these diseases, including Alzheimer’s disease (AD), makes Wnt signaling an attractive target for therapies. Interestingly, novel Wnt signaling activating compounds are less frequently described than inhibitors, turning the quest for novel positive modulators even more appealing. In that sense, natural compounds are an outstanding source of potential drug leads. Here, we combine different experimental models, cell-based approaches, neuronal culture assays, and rodent behavior tests with Xenopus laevis phenotypic analysis to characterize quercitrin, a natural compound, as a novel Wnt signaling potentiator. We find that quercitrin potentiates the signaling in a concentration-dependent manner and increases the occurrence of the Xenopus secondary axis phenotype mediated by Xwnt8 injection. Using a GSK3 biosensor, we describe that quercitrin impairs GSK3 activity and increases phosphorylated GSK3β S9 levels. Treatment with XAV939, an inhibitor downstream of GSK3, impairs the quercitrin-mediated effect. Next, we show that quercitrin potentiates the Wnt3a-synaptogenic effect in hippocampal neurons in culture, which is blocked by XAV939. Quercitrin treatment also rescues the hippocampal synapse loss induced by intracerebroventricular injection of amyloid-β oligomers (AβO) in mice. Finally, quercitrin rescues AβO-mediated memory impairment, which is prevented by XAV939. Thus, our study uncovers a novel function for quercitrin as a Wnt/β-catenin signaling potentiator, describes its mechanism of action, and opens new avenues for AD treatments.
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Affiliation(s)
- Danilo Predes
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Lorena A. Maia
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Isadora Matias
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | | | - Carolina Soares
- Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-901, Brazil
| | | | - Luiz F. S. Oliveira
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Renata R. Reis
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Nathalia G. Amado
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Alessandro B. C. Simas
- Instituto de Pesquisas de Produtos Naturais Walter Mors, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-901, Brazil
| | - Fabio A. Mendes
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Flávia C. A. Gomes
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Claudia P. Figueiredo
- Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-901, Brazil
| | - Jose G. Abreu
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
- Correspondence: ; Tel.: +55-21-3938-6486
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9
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Morris A, Hoyle R, Pagare PP, Uz Zaman S, Ma Z, Li J, Zhang Y. Exploration of Naphthoquinone Analogs in Targeting the TCF-DNA Interaction to Inhibit the Wnt/β-catenin Signaling Pathway. Bioorg Chem 2022; 124:105812. [DOI: 10.1016/j.bioorg.2022.105812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 04/11/2022] [Accepted: 04/12/2022] [Indexed: 11/02/2022]
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10
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Garg C, khan H, Kaur A, Singh TG, Sharma VK, Singh SK. Therapeutic Implications of Sonic Hedgehog Pathway in Metabolic Disorders: Novel Target for Effective Treatment. Pharmacol Res 2022; 179:106194. [DOI: 10.1016/j.phrs.2022.106194] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2021] [Revised: 03/24/2022] [Accepted: 03/24/2022] [Indexed: 12/13/2022]
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11
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Bou-Rouphael J, Durand BC. T-Cell Factors as Transcriptional Inhibitors: Activities and Regulations in Vertebrate Head Development. Front Cell Dev Biol 2021; 9:784998. [PMID: 34901027 PMCID: PMC8651982 DOI: 10.3389/fcell.2021.784998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 10/28/2021] [Indexed: 11/22/2022] Open
Abstract
Since its first discovery in the late 90s, Wnt canonical signaling has been demonstrated to affect a large variety of neural developmental processes, including, but not limited to, embryonic axis formation, neural proliferation, fate determination, and maintenance of neural stem cells. For decades, studies have focused on the mechanisms controlling the activity of β-catenin, the sole mediator of Wnt transcriptional response. More recently, the spotlight of research is directed towards the last cascade component, the T-cell factor (TCF)/Lymphoid-Enhancer binding Factor (LEF), and more specifically, the TCF/LEF-mediated switch from transcriptional activation to repression, which in both embryonic blastomeres and mouse embryonic stem cells pushes the balance from pluri/multipotency towards differentiation. It has been long known that Groucho/Transducin-Like Enhancer of split (Gro/TLE) is the main co-repressor partner of TCF/LEF. More recently, other TCF/LEF-interacting partners have been identified, including the pro-neural BarH-Like 2 (BARHL2), which belongs to the evolutionary highly conserved family of homeodomain-containing transcription factors. This review describes the activities and regulatory modes of TCF/LEF as transcriptional repressors, with a specific focus on the functions of Barhl2 in vertebrate brain development. Specific attention is given to the transcriptional events leading to formation of the Organizer, as well as the roles and regulations of Wnt/β-catenin pathway in growth of the caudal forebrain. We present TCF/LEF activities in both embryonic and neural stem cells and discuss how alterations of this pathway could lead to tumors.
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Affiliation(s)
| | - Béatrice C. Durand
- Sorbonne Université, CNRS UMR7622, IBPS Developmental Biology Laboratory, Campus Pierre et Marie Curie, Paris, France
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12
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Zhu X, Wang P, Wei J, Li Y, Zhai J, Zheng T, Tao Q. Lysosomal degradation of the maternal dorsal determinant Hwa safeguards dorsal body axis formation. EMBO Rep 2021; 22:e53185. [PMID: 34652064 DOI: 10.15252/embr.202153185] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 09/15/2021] [Accepted: 09/29/2021] [Indexed: 01/09/2023] Open
Abstract
The Spemann and Mangold Organizer (SMO) is of fundamental importance for dorsal ventral body axis formation during vertebrate embryogenesis. Maternal Huluwa (Hwa) has been identified as the dorsal determinant that is both necessary and sufficient for SMO formation. However, it remains unclear how Hwa is regulated. Here, we report that the E3 ubiquitin ligase zinc and ring finger 3 (ZNRF3) is essential for restricting the spatial activity of Hwa and therefore correct SMO formation in Xenopus laevis. ZNRF3 interacts with and ubiquitinates Hwa, thereby regulating its lysosomal trafficking and protein stability. Perturbation of ZNRF3 leads to the accumulation of Hwa and induction of an ectopic axis in embryos. Ectopic expression of ZNRF3 promotes Hwa degradation and dampens the axis-inducing activity of Hwa. Thus, our findings identify a substrate of ZNRF3, but also highlight the importance of the regulation of Hwa temporospatial activity in body axis formation in vertebrate embryos.
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Affiliation(s)
- Xuechen Zhu
- MOE Key Laboratory of Protein Sciences, School of Life Sciences, Tsinghua University, Beijing, China.,Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, China
| | - Pan Wang
- Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China.,Beijing Advanced Innovation Center for Structural Biology, Beijing, China
| | - Jiale Wei
- MOE Key Laboratory of Protein Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Yongyu Li
- MOE Key Laboratory of Protein Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Jiayu Zhai
- MOE Key Laboratory of Protein Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Tianrui Zheng
- MOE Key Laboratory of Protein Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Qinghua Tao
- MOE Key Laboratory of Protein Sciences, School of Life Sciences, Tsinghua University, Beijing, China.,Beijing Advanced Innovation Center for Structural Biology, Beijing, China
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Hedgehog/GLI Signaling Pathway: Transduction, Regulation, and Implications for Disease. Cancers (Basel) 2021; 13:cancers13143410. [PMID: 34298625 PMCID: PMC8304605 DOI: 10.3390/cancers13143410] [Citation(s) in RCA: 82] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 07/04/2021] [Accepted: 07/05/2021] [Indexed: 12/12/2022] Open
Abstract
Simple Summary The Hedgehog/GLI (Hh/GLI) pathway plays a major role during development and it is commonly dysregulated in many diseases, including cancer. This highly concerted series of ligands, receptors, cytoplasmic signaling molecules, transcription factors, and co-regulators is involved in regulating the biological functions controlled by this pathway. Activation of Hh/GLI in cancer is most often through a non-canonical method of activation, independent of ligand binding. This review is intended to summarize our current understanding of the Hh/GLI signaling, non-canonical mechanisms of pathway activation, its implication in disease, and the current therapeutic strategies targeting this cascade. Abstract The Hh/GLI signaling pathway was originally discovered in Drosophila as a major regulator of segment patterning in development. This pathway consists of a series of ligands (Shh, Ihh, and Dhh), transmembrane receptors (Ptch1 and Ptch2), transcription factors (GLI1–3), and signaling regulators (SMO, HHIP, SUFU, PKA, CK1, GSK3β, etc.) that work in concert to repress (Ptch1, Ptch2, SUFU, PKA, CK1, GSK3β) or activate (Shh, Ihh, Dhh, SMO, GLI1–3) the signaling cascade. Not long after the initial discovery, dysregulation of the Hh/GLI signaling pathway was implicated in human disease. Activation of this signaling pathway is observed in many types of cancer, including basal cell carcinoma, medulloblastoma, colorectal, prostate, pancreatic, and many more. Most often, the activation of the Hh/GLI pathway in cancer occurs through a ligand-independent mechanism. However, in benign disease, this activation is mostly ligand-dependent. The upstream signaling component of the receptor complex, SMO, is bypassed, and the GLI family of transcription factors can be activated regardless of ligand binding. Additional mechanisms of pathway activation exist whereby the entirety of the downstream signaling pathway is bypassed, and PTCH1 promotes cell cycle progression and prevents caspase-mediated apoptosis. Throughout this review, we summarize each component of the signaling cascade, non-canonical modes of pathway activation, and the implications in human disease, including cancer.
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Foxh1/Nodal Defines Context-Specific Direct Maternal Wnt/β-Catenin Target Gene Regulation in Early Development. iScience 2020; 23:101314. [PMID: 32650116 PMCID: PMC7347983 DOI: 10.1016/j.isci.2020.101314] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 05/20/2020] [Accepted: 06/20/2020] [Indexed: 12/19/2022] Open
Abstract
Although Wnt/β-catenin signaling is generally conserved and well understood, the regulatory mechanisms controlling context-specific direct Wnt target gene expression in development and disease are still unclear. The onset of zygotic gene transcription in early embryogenesis represents an ideal, accessible experimental system to investigate context-specific direct Wnt target gene regulation. We combine transcriptomics using RNA-seq with genome-wide β-catenin association using ChIP-seq to identify stage-specific direct Wnt target genes. We propose coherent feedforward regulation involving two distinct classes of direct maternal Wnt target genes, which differ both in expression and persistence of β-catenin association. We discover that genomic β-catenin association overlaps with Foxh1-associated regulatory sequences and demonstrate that direct maternal Wnt target gene expression requires Foxh1 function and Nodal/Tgfβ signaling. Our results support a new paradigm for direct Wnt target gene co-regulation with context-specific mechanisms that will inform future studies of embryonic development and more widely stem cell-mediated homeostasis and human disease. Combining RNA-seq and β-catenin ChIP-seq identifies direct Wnt target genes Two distinct classes of direct maternal Wnt/β-catenin target genes can be discerned We propose coherent feedforward regulation of gene expression of the second class Maternal Wnt target gene expression of both classes requires Nodal/Foxh1 signaling
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15
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Esmaeili M, Blythe SA, Tobias JW, Zhang K, Yang J, Klein PS. Chromatin accessibility and histone acetylation in the regulation of competence in early development. Dev Biol 2020; 462:20-35. [PMID: 32119833 PMCID: PMC7225061 DOI: 10.1016/j.ydbio.2020.02.013] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 01/29/2020] [Accepted: 02/25/2020] [Indexed: 02/06/2023]
Abstract
As development proceeds, inductive cues are interpreted by competent tissues in a spatially and temporally restricted manner. While key inductive signaling pathways within competent cells are well-described at a molecular level, the mechanisms by which tissues lose responsiveness to inductive signals are not well understood. Localized activation of Wnt signaling before zygotic gene activation in Xenopus laevis leads to dorsal development, but competence to induce dorsal genes in response to Wnts is lost by the late blastula stage. We hypothesize that loss of competence is mediated by changes in histone modifications leading to a loss of chromatin accessibility at the promoters of Wnt target genes. We use ATAC-seq to evaluate genome-wide changes in chromatin accessibility across several developmental stages. Based on overlap with p300 binding, we identify thousands of putative cis-regulatory elements at the gastrula stage, including sites that lose accessibility by the end of gastrulation and are enriched for pluripotency factor binding motifs. Dorsal Wnt target gene promoters are not accessible after the loss of competence in the early gastrula while genes involved in mesoderm and neural crest development maintain accessibility at their promoters. Inhibition of histone deacetylases increases acetylation at the promoters of dorsal Wnt target genes and extends competence for dorsal gene induction by Wnt signaling. Histone deacetylase inhibition, however, is not sufficient to extend competence for mesoderm or neural crest induction. These data suggest that chromatin state regulates the loss of competence to inductive signals in a context-dependent manner.
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Affiliation(s)
- Melody Esmaeili
- Cell and Molecular Biology Graduate Group, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Shelby A Blythe
- Department of Molecular Biosciences, Northwestern University, Evanston, IL, USA
| | - John W Tobias
- Penn Genomic Analysis Core and Abramson Cancer Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Kai Zhang
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Jing Yang
- Department of Comparative Biosciences, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
| | - Peter S Klein
- Cell and Molecular Biology Graduate Group, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA; Departments of Medicine (Hematology-Oncology) and Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA.
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16
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Redundant and additive functions of the four Lef/Tcf transcription factors in lung epithelial progenitors. Proc Natl Acad Sci U S A 2020; 117:12182-12191. [PMID: 32414917 DOI: 10.1073/pnas.2002082117] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
In multicellular organisms, paralogs from gene duplication survive purifying selection by evolving tissue-specific expression and function. Whether this genetic redundancy is also selected for within a single cell type is unclear for multimember paralogs, as exemplified by the four obligatory Lef/Tcf transcription factors of canonical Wnt signaling, mainly due to the complex genetics involved. Using the developing mouse lung as a model system, we generate two quadruple conditional knockouts, four triple mutants, and various combinations of double mutants, showing that the four Lef/Tcf genes function redundantly in the presence of at least two Lef/Tcf paralogs, but additively upon losing additional paralogs to specify and maintain lung epithelial progenitors. Prelung-specification, pan-epithelial double knockouts have no lung phenotype; triple knockouts have varying phenotypes, including defective branching and tracheoesophageal fistulas; and the quadruple knockout barely forms a lung, resembling the Ctnnb1 mutant. Postlung-specification deletion of all four Lef/Tcf genes leads to branching defects, down-regulation of progenitor genes, premature alveolar differentiation, and derepression of gastrointestinal genes, again phenocopying the corresponding Ctnnb1 mutant. Our study supports a monotonic, positive signaling relationship between CTNNB1 and Lef/Tcf in lung epithelial progenitors as opposed to reported repressor functions of Lef/Tcf, and represents a thorough in vivo analysis of cell-type-specific genetic redundancy among the four Lef/Tcf paralogs.
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17
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Wang X, Cai L, Xie JX, Cui X, Zhang J, Wang J, Chen Y, Larre I, Shapiro JI, Pierre SV, Wu D, Zhu GZ, Xie Z. A caveolin binding motif in Na/K-ATPase is required for stem cell differentiation and organogenesis in mammals and C. elegans. SCIENCE ADVANCES 2020; 6:eaaw5851. [PMID: 32537485 PMCID: PMC7253156 DOI: 10.1126/sciadv.aaw5851] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 03/02/2020] [Indexed: 05/15/2023]
Abstract
Several signaling events have been recognized as essential for regulating cell lineage specification and organogenesis in animals. We find that the gain of an amino-terminal caveolin binding motif (CBM) in the α subunit of the Na/K-adenosine triphosphatase (ATPase) (NKA) is required for the early stages of organogenesis in both mice and Caenorhabditis elegans. The evolutionary gain of the CBM occurred at the same time as the acquisition of the binding sites for Na+/K+. Loss of this CBM does not affect cell lineage specification or the initiation of organogenesis, but arrests further organ development. Mechanistically, this CBM is essential for the dynamic operation of Wnt and the timely up-regulation of transcriptional factors during organogenesis. These results indicate that the NKA was evolved as a dual functional protein that works in concert with Wnt as a hitherto unrecognized common mechanism to enable stem cell differentiation and organogenesis in multicellular organisms within the animal kingdom.
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Affiliation(s)
- Xiaoliang Wang
- Marshall Institute for Interdisciplinary Research (MIIR) at Marshall University, Huntington, WV, USA
| | - Liquan Cai
- Marshall Institute for Interdisciplinary Research (MIIR) at Marshall University, Huntington, WV, USA
| | - Jeffrey X. Xie
- University of Toledo College of Medicine and Life Sciences, Toledo, OH, USA
| | - Xiaoyu Cui
- Marshall Institute for Interdisciplinary Research (MIIR) at Marshall University, Huntington, WV, USA
| | - Jue Zhang
- Marshall Institute for Interdisciplinary Research (MIIR) at Marshall University, Huntington, WV, USA
| | - Jiayan Wang
- Marshall Institute for Interdisciplinary Research (MIIR) at Marshall University, Huntington, WV, USA
| | - Yiliang Chen
- Blood Research Institute, Blood Center of Wisconsin, Milwaukee, WI, USA
| | - Isabel Larre
- Marshall Institute for Interdisciplinary Research (MIIR) at Marshall University, Huntington, WV, USA
| | - Joseph I. Shapiro
- Joan C. Edwards School of Medicine at Marshall University, Huntington, WV, USA
| | - Sandrine V. Pierre
- Marshall Institute for Interdisciplinary Research (MIIR) at Marshall University, Huntington, WV, USA
| | - Dianqing Wu
- Department of Pharmacology and Vascular Biology and Therapeutics, Yale School of Medicine, New Haven, CT, USA
| | - Guo-Zhang Zhu
- Marshall Institute for Interdisciplinary Research (MIIR) at Marshall University, Huntington, WV, USA
- Department of Biological Sciences, Marshall University, Huntington, WV, USA
| | - Zijian Xie
- Marshall Institute for Interdisciplinary Research (MIIR) at Marshall University, Huntington, WV, USA
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18
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Paraiso KD, Cho JS, Yong J, Cho KWY. Early Xenopus gene regulatory programs, chromatin states, and the role of maternal transcription factors. Curr Top Dev Biol 2020; 139:35-60. [PMID: 32450966 DOI: 10.1016/bs.ctdb.2020.02.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
For decades, the early development of the Xenopus embryo has been an essential model system to study the gene regulatory mechanisms that govern cellular specification. At the top of the hierarchy of gene regulatory networks, maternally deposited transcription factors initiate this process and regulate the expression of zygotic genes that give rise to three distinctive germ layer cell types (ectoderm, mesoderm, and endoderm), and subsequent generation of organ precursors. The onset of germ layer specification is also closely coupled with changes associated with chromatin modifications. This review will examine the timing of maternal transcription factors initiating the zygotic genome activation, the epigenetic landscape of embryonic chromatin, and the network structure that governs the process.
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Affiliation(s)
- Kitt D Paraiso
- Department of Developmental and Cell Biology, University of California, Irvine, CA, United States; Center for Complex Biological Systems, University of California, Irvine, CA, United States
| | - Jin S Cho
- Department of Developmental and Cell Biology, University of California, Irvine, CA, United States
| | - Junseok Yong
- Department of Developmental and Cell Biology, University of California, Irvine, CA, United States
| | - Ken W Y Cho
- Department of Developmental and Cell Biology, University of California, Irvine, CA, United States; Center for Complex Biological Systems, University of California, Irvine, CA, United States.
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19
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Li X, Ortiz MA, Kotula L. The physiological role of Wnt pathway in normal development and cancer. Exp Biol Med (Maywood) 2020; 245:411-426. [PMID: 31996036 PMCID: PMC7082880 DOI: 10.1177/1535370220901683] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Over the decades, many studies have illustrated the critical roles of Wnt signaling pathways in both developmental processes as well as tumorigenesis. Due to the complexity of Wnt signaling regulation, there are still questions to be addressed about ways cells are able to manipulate different types of Wnt pathways in order to fulfill the requirements for normal or cancer development. In this review, we will describe different types of Wnt signaling pathways and their roles in both normal developmental processes and their role in cancer development and progression. Additionally, we will briefly introduce new strategies currently in clinical trials targeting Wnt signaling pathway components for cancer therapy.
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Affiliation(s)
- Xiang Li
- Department of Urology, SUNY Upstate Medical University, Syracuse, NY 13210, USA
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, NY 13210, USA
- Upstate Cancer Center, SUNY Upstate Medical University, Syracuse, NY 13210, USA
| | - Maria A Ortiz
- Department of Urology, SUNY Upstate Medical University, Syracuse, NY 13210, USA
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, NY 13210, USA
- Upstate Cancer Center, SUNY Upstate Medical University, Syracuse, NY 13210, USA
| | - Leszek Kotula
- Department of Urology, SUNY Upstate Medical University, Syracuse, NY 13210, USA
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, NY 13210, USA
- Upstate Cancer Center, SUNY Upstate Medical University, Syracuse, NY 13210, USA
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20
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Melchert J, Henningfeld KA, Richts S, Lingner T, Jonigk D, Pieler T. The secreted BMP antagonist ERFE is required for the development of a functional circulatory system in Xenopus. Dev Biol 2019; 459:138-148. [PMID: 31846624 DOI: 10.1016/j.ydbio.2019.12.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 12/03/2019] [Accepted: 12/12/2019] [Indexed: 01/24/2023]
Abstract
The hormone Erythroferrone (ERFE) is a member of the C1q/TNF-related protein family that regulates iron homeostasis through the suppression of hamp. In a gain of function screen in Xenopus embryos, we identified ERFE as a potent secondary axis-inducing agent. Experiments in Xenopus embryos and ectodermal explants revealed that ERFE functions as a selective inhibitor of the BMP pathway and the conserved C1q domain is not required for this activity. Inhibition occurs at the extracelluar level, through the interaction of ERFE with the BMP ligand. During early Xenopus embryogenesis, erfe is first expressed in the ventral blood islands where initial erythropoiesis occurs and later in circulating blood cells. ERFE knockdown does not alter the expression of etv.2, aplnr and flt1 in tailbud stage embryos indicating endothelial cell specification is independent of ERFE. However, in tadpole embryos, defects of the vascular network and primitive blood circulation are observed as well as edema formation. RNAseq analysis of ERFE morphant embryos also revealed the inhibition of gja4 indicating disruption of dorsal aorta formation.
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Affiliation(s)
- Juliane Melchert
- Institute of Developmental Biochemistry, University Medical Center Göttingen, Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Justus-von-Liebig-Weg 11, 37077, Goettingen, Germany.
| | - Kristine A Henningfeld
- Institute of Developmental Biochemistry, University Medical Center Göttingen, Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Justus-von-Liebig-Weg 11, 37077, Goettingen, Germany
| | - Sven Richts
- Institute of Developmental Biochemistry, University Medical Center Göttingen, Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Justus-von-Liebig-Weg 11, 37077, Goettingen, Germany
| | - Thomas Lingner
- Transcriptome and Genome Analysis Laboratory, University Medical Center Göttingen, Justus-von-Liebig-Weg 11, 37077, Göttingen, Germany
| | - Danny Jonigk
- Institut für Pathologie, Medizinische Hochschule Hannover (MHH) Hannover, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Tomas Pieler
- Institute of Developmental Biochemistry, University Medical Center Göttingen, Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Justus-von-Liebig-Weg 11, 37077, Goettingen, Germany
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21
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Pelullo M, Zema S, Nardozza F, Checquolo S, Screpanti I, Bellavia D. Wnt, Notch, and TGF-β Pathways Impinge on Hedgehog Signaling Complexity: An Open Window on Cancer. Front Genet 2019; 10:711. [PMID: 31552081 PMCID: PMC6736567 DOI: 10.3389/fgene.2019.00711] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Accepted: 07/05/2019] [Indexed: 12/22/2022] Open
Abstract
Constitutive activation of the Hedgehog (Hh) signaling pathway is associated with increased risk of developing several malignancies. The biological and pathogenic importance of Hh signaling emphasizes the need to control its action tightly, both physiologically and therapeutically. Evidence of crosstalk between Hh and other signaling pathways is reported in many tumor types. Here, we provide an overview of the current knowledge about the communication between Hh and major signaling pathways, such as Notch, Wnt, and transforming growth factor β (TGF-β), which play critical roles in both embryonic and adult life. When these pathways are unbalanced, impaired crosstalk contributes to disease development. It is reported that more than one of these pathways are active in different type of tumors, at the same time. Therefore, starting from a plethora of stimuli that activate multiple signaling pathways, we describe the signals that preferentially converge on the Hh signaling cascade that influence its activity. Moreover, we highlight several connection points between Hh and Notch, Wnt, or TGF-β pathways, showing a reciprocal synergism that contributes to tumorigenesis, supporting a more malignant behavior by tumor cells, such as in leukemia and brain tumors. Understanding the importance of these molecular interlinking networks will provide a rational basis for combined anticancer drug development.
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Affiliation(s)
- Maria Pelullo
- Center of Life Nano Science Sapienza, Istituto Italiano di Tecnologia, Rome, Italy
| | - Sabrina Zema
- Department of Molecular Medicine, Sapienza University, Rome, Italy
| | | | - Saula Checquolo
- Department of Medico-Surgical Sciences and Biotechnologies, Sapienza University, Latina, Italy
| | | | - Diana Bellavia
- Department of Molecular Medicine, Sapienza University, Rome, Italy
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22
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Kjolby RAS, Truchado-Garcia M, Iruvanti S, Harland RM. Integration of Wnt and FGF signaling in the Xenopus gastrula at TCF and Ets binding sites shows the importance of short-range repression by TCF in patterning the marginal zone. Development 2019; 146:dev179580. [PMID: 31285353 PMCID: PMC6703714 DOI: 10.1242/dev.179580] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 06/26/2019] [Indexed: 12/12/2022]
Abstract
During Xenopus gastrulation, Wnt and FGF signaling pathways cooperate to induce posterior structures. Wnt target expression around the blastopore falls into two main categories: a horseshoe shape with a dorsal gap, as in Wnt8 expression; or a ring, as in FGF8 expression. Using ChIP-seq, we show, surprisingly, that the FGF signaling mediator Ets2 binds near all Wnt target genes. However, β-catenin preferentially binds at the promoters of genes with horseshoe patterns, but further from the promoters of genes with ring patterns. Manipulation of FGF or Wnt signaling demonstrated that 'ring' genes are responsive to FGF signaling at the dorsal midline, whereas 'horseshoe' genes are predominantly regulated by Wnt signaling. We suggest that, in the absence of active β-catenin at the dorsal midline, the DNA-binding protein TCF binds and actively represses gene activity only when close to the promoter. In contrast, genes without functional TCF sites at the promoter may be predominantly regulated by Ets at the dorsal midline and are expressed in a ring. These results suggest recruitment of only short-range repressors to potential Wnt targets in the Xenopus gastrula.
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Affiliation(s)
- Rachel A S Kjolby
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA
| | - Marta Truchado-Garcia
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA
| | - Suvruta Iruvanti
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA
| | - Richard M Harland
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA
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23
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Lichtig H, Cohen Y, Bin-Nun N, Golubkov V, Frank D. PTK7 proteolytic fragment proteins function during early Xenopus development. Dev Biol 2019; 453:48-55. [PMID: 31125531 DOI: 10.1016/j.ydbio.2019.05.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 05/20/2019] [Accepted: 05/20/2019] [Indexed: 12/12/2022]
Abstract
Protein Tyrosine Kinase 7 (PTK7) is as a critical regulator of canonical and non-canonical Wnt-signaling during embryonic development and cancer cell formation. Disrupting PTK7 activity perturbs vertebrate nervous system development, and also promotes human cancer formation. Observations in different model systems suggest a complex cross-talk between PTK7 protein and Wnt signaling. During Xenopus laevis nervous system development, we previously showed that PTK7 protein positively regulates canonical Wnt signaling by maintaining optimal LRP6 protein levels, but PTK7 also acts in concert with LRP6 protein to repress non-canonical Wnt activity. PTK7 is a transmembrane protein, but studies in cancer cells showed that PTK7 undergoes "shedding" by metalloproteases to different proteolytic fragments. Some PTK7 proteolytic fragments are oncogenic, being localized to alternative cytoplasmic and nuclear cell compartments. In this study we examined the biological activity of two proteolytic carboxyl-terminal PTK7 proteolytic fragments, cPTK7 622-1070 and cPTK7 726-1070 during early Xenopus nervous system development. We found that these smaller PTK7 proteolytic fragments have similar activity to full-length PTK7 protein to promote canonical Wnt-signaling via regulation of LRP6 protein levels. In addition to cancer systems, this study shows in vivo proof that these smaller PTK7 proteolytic fragments can recapitulate full-length PTK7 protein activity in diverse systems, such as vertebrate nervous system development.
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Affiliation(s)
- Hava Lichtig
- Department of Biochemistry, The Rappaport Family Institute for Research in the Medical Sciences, Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, 31096, Israel
| | - Yasmin Cohen
- Department of Biochemistry, The Rappaport Family Institute for Research in the Medical Sciences, Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, 31096, Israel
| | - Naama Bin-Nun
- Department of Biochemistry, The Rappaport Family Institute for Research in the Medical Sciences, Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, 31096, Israel
| | | | - Dale Frank
- Department of Biochemistry, The Rappaport Family Institute for Research in the Medical Sciences, Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, 31096, Israel.
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24
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Han S, Jin X, Liu Z, Xing F, Han Y, Yu X, He G, Qiu F. The long noncoding RNA HOTTIP promotes breast cancer cell migration, invasiveness, and epithelial-mesenchymal transition via the Wnt-β-catenin signaling pathway. Biochem Cell Biol 2019; 97:655-664. [PMID: 30676763 DOI: 10.1139/bcb-2018-0313] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Long noncoding RNA HOTTIP (HOXA transcript at the distal tip) has recently been reported to have a role in the proliferation of various cancer cells, yet its role in cell migration, invasiveness, and the EMT (epithelial-mesenchymal transition) in breast cancer and the potential mechanisms remain unknown. Breast cancer cell lines MDA-MB-231 and MDA-MB-468 were transfected with shRNA (short hairpin RNA) that specifically targeting HOTTIP. We observed a remarkable decrease in migration and invasiveness in these two breast cancer cell lines after knock-down of HOTTIP by shHOTTIP. We also demonstrated that the EMT of these two breast cell lines was suppressed after HOTTIP knock-down, as evidenced by increased E-cadherin levels, and decreased levels of N-cadherin, Snail, and Twist. Moreover, HOTTIP silencing also suppressed tumor metastasis in nude mice in vivo. In addition, we found that the expression of β-catenin was significantly decreased in breast cancer cells after knock-down of HOTTIP. In a further rescue experiment using overexpression of β-catenin, the rates of cell migration, invasiveness, and EMT of HOTTIP-silenced breast cancer cells were promoted, disclosing a potential role of the Wnt-β-catenin signaling pathway in this process. Overall, we discovered the positive regulatory function of HOTTIP in the migration, invasiveness, and EMT of breast cancer cells, via regulating the Wnt-β-catenin pathway.
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Affiliation(s)
- Sijia Han
- Department of Breast Surgery, Shengjing Hospital of China Medical University, Shenyang 110004, People's Republic of China
| | - Xiaoming Jin
- Department of Endocrinology, Northern Theater Command Airforce Hospital of Chinese PLA, Shenyang 110042, People's Republic of China
| | - Zhen Liu
- Department of General Surgery, Shengjing Hospital of China Medical University, Shenyang 110004, People's Republic of China
| | - Fei Xing
- Department of Breast Surgery, Shengjing Hospital of China Medical University, Shenyang 110004, People's Republic of China
| | - Ye Han
- Department of Breast Surgery, Shengjing Hospital of China Medical University, Shenyang 110004, People's Republic of China
| | - Xiaopeng Yu
- Department of Breast Surgery, Shengjing Hospital of China Medical University, Shenyang 110004, People's Republic of China
| | - Guijin He
- Department of Breast Surgery, Shengjing Hospital of China Medical University, Shenyang 110004, People's Republic of China
| | - Fang Qiu
- Department of Breast Surgery, Shengjing Hospital of China Medical University, Shenyang 110004, People's Republic of China
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25
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Liang R, Liu Y. Tcf7l1 directly regulates cardiomyocyte differentiation in embryonic stem cells. Stem Cell Res Ther 2018; 9:267. [PMID: 30326964 PMCID: PMC6190650 DOI: 10.1186/s13287-018-1015-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Revised: 09/18/2018] [Accepted: 09/21/2018] [Indexed: 01/19/2023] Open
Abstract
The T-cell factor/lymphoid enhancer factor (TCF/LEF) family protein Tcf7l1 is highly abundant in embryonic stem cells (ESCs), regulating pluripotency and preparing epiblasts for further differentiation. Defects in the cardiovascular system in Tcf7l1-null mouse were considered secondary to mesoderm malformation. Here, we used temporally controlled Tcf7l1 expression in Tcf7l1-null ESCs to address whether Tcf7l1 directly contributes to cardiac forward programming. Tcf7l1 knockout during differentiation impaired cardiomyocyte formation but did not affect mesoderm formation. Tcf7l1-null ESCs showed delay in mesoderm formation, but once completed, ectopic Tcf7l1 augmented cardiomyocyte differentiation. Further, Tcf7l1-VP16 and Tcf7l1dN showed procardiac activity whereas Tcf7l1-En was ineffective. Our results support that Tcf7l1 contributes to cardiac lineage development as a β-catenin-independent transactivator of cardiac genes.
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Affiliation(s)
- Rui Liang
- Department of Biology and Biochemistry, University of Houston, Houston, TX, 77004, USA
| | - Yu Liu
- Department of Biology and Biochemistry, University of Houston, Houston, TX, 77004, USA.
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26
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Harder M, Reeves W, Byers C, Santiago M, Veeman M. Multiple inputs into a posterior-specific regulatory network in the Ciona notochord. Dev Biol 2018; 448:136-146. [PMID: 30287118 DOI: 10.1016/j.ydbio.2018.09.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 09/04/2018] [Accepted: 09/28/2018] [Indexed: 11/28/2022]
Abstract
The gene regulatory networks underlying Ciona notochord fate specification and differentiation have been extensively investigated, but the regulatory basis for regionalized expression within the notochord is not understood. Here we identify three notochord-expressed genes, C11.331, C12.115 and C8.891, with strongly enriched expression in the secondary notochord cells at the posterior tip of the tail. C11.331 and C12.115 share a distinctive expression pattern that is highly enriched in the secondary notochord lineage but also graded within that lineage with the strongest expression at the posterior tip. Both genes show similar responses to pharmacological perturbations of Wnt and FGF signaling, consistent with an important role for Wnt and FGF ligands expressed at the tail tip. Reporter analysis indicates that the C11.331 cis-regulatory regions are extensively distributed, with multiple non-overlapping regions conferring posterior notochord-enriched expression. Fine-scale analysis of a minimal cis-regulatory module identifies discrete positive and negative elements including a strong silencer. Truncation of the silencer region leads to increased expression in the primary notochord, indicating that C11.331 expression is influenced by putative regulators of primary versus secondary notochord fate. The minimal CRM contains predicted ETS, GATA, LMX and Myb sites, all of which lead to reduced expression in secondary notochord when mutated. These results show that the posterior-enriched notochord expression of C11.331 depends on multiple inputs, including Wnt and FGF signals from the tip of the tail, multiple notochord-specific regulators, and yet-to-be identified regulators of regional identity within the notochord.
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Affiliation(s)
- Matthew Harder
- Division of Biology, Kansas State University, Manhattan, KS 66506, USA
| | - Wendy Reeves
- Division of Biology, Kansas State University, Manhattan, KS 66506, USA
| | - Chase Byers
- Division of Biology, Kansas State University, Manhattan, KS 66506, USA
| | - Mercedes Santiago
- Division of Biology, Kansas State University, Manhattan, KS 66506, USA
| | - Michael Veeman
- Division of Biology, Kansas State University, Manhattan, KS 66506, USA.
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27
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Bozatzi P, Dingwell KS, Wu KZ, Cooper F, Cummins TD, Hutchinson LD, Vogt J, Wood NT, Macartney TJ, Varghese J, Gourlay R, Campbell DG, Smith JC, Sapkota GP. PAWS1 controls Wnt signalling through association with casein kinase 1α. EMBO Rep 2018; 19:e44807. [PMID: 29514862 PMCID: PMC5891436 DOI: 10.15252/embr.201744807] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 02/05/2018] [Accepted: 02/08/2018] [Indexed: 12/17/2022] Open
Abstract
The BMP and Wnt signalling pathways determine axis specification during embryonic development. Our previous work has shown that PAWS1 (also known as FAM83G) interacts with SMAD1 and modulates BMP signalling. Here, surprisingly, we show that overexpression of PAWS1 in Xenopus embryos activates Wnt signalling and causes complete axis duplication. Consistent with these observations in Xenopus, Wnt signalling is diminished in U2OS osteosarcoma cells lacking PAWS1, while BMP signalling is unaffected. We show that PAWS1 interacts and co-localises with the α isoform of casein kinase 1 (CK1), and that PAWS1 mutations incapable of binding CK1 fail both to activate Wnt signalling and to elicit axis duplication in Xenopus embryos.
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Affiliation(s)
- Polyxeni Bozatzi
- Medical Research Council Protein Phosphorylation and Ubiquitylation Unit, Dundee, UK
| | | | - Kevin Zl Wu
- Medical Research Council Protein Phosphorylation and Ubiquitylation Unit, Dundee, UK
| | | | - Timothy D Cummins
- Medical Research Council Protein Phosphorylation and Ubiquitylation Unit, Dundee, UK
| | - Luke D Hutchinson
- Medical Research Council Protein Phosphorylation and Ubiquitylation Unit, Dundee, UK
| | - Janis Vogt
- Medical Research Council Protein Phosphorylation and Ubiquitylation Unit, Dundee, UK
| | - Nicola T Wood
- Medical Research Council Protein Phosphorylation and Ubiquitylation Unit, Dundee, UK
| | - Thomas J Macartney
- Medical Research Council Protein Phosphorylation and Ubiquitylation Unit, Dundee, UK
| | - Joby Varghese
- Medical Research Council Protein Phosphorylation and Ubiquitylation Unit, Dundee, UK
| | - Robert Gourlay
- Medical Research Council Protein Phosphorylation and Ubiquitylation Unit, Dundee, UK
| | - David G Campbell
- Medical Research Council Protein Phosphorylation and Ubiquitylation Unit, Dundee, UK
| | | | - Gopal P Sapkota
- Medical Research Council Protein Phosphorylation and Ubiquitylation Unit, Dundee, UK
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28
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Elliott KH, Brugmann SA. Sending mixed signals: Cilia-dependent signaling during development and disease. Dev Biol 2018; 447:28-41. [PMID: 29548942 DOI: 10.1016/j.ydbio.2018.03.007] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 03/03/2018] [Accepted: 03/06/2018] [Indexed: 01/09/2023]
Abstract
Molecular signals are the guiding force of development, imparting direction upon cells to divide, migrate, differentiate, etc. The mechanisms by which a cell can receive and transduce these signals into measurable actions remains a 'black box' in developmental biology. Primary cilia are ubiquitous, microtubule-based organelles that dynamically extend from a cell to receive and process molecular and mechanical signaling cues. In the last decade, this organelle has become increasingly intriguing to the research community due to its ability to act as a cellular antenna, receive and transduce molecular stimuli, and initiate a cellular response. In this review, we discuss the structure of primary cilia, emphasizing how the ciliary components contribute to the transduction of signaling pathways. Furthermore, we address how the cilium integrates these signals and conveys them into cellular processes such as proliferation, migration and tissue patterning. Gaining a deeper understanding of the mechanisms used by primary cilia to receive and integrate molecular signals is essential, as it opens the door for the identification of therapeutic targets within the cilium that could alleviate pathological conditions brought on by aberrant molecular signaling.
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Affiliation(s)
- Kelsey H Elliott
- Division of Plastic Surgery, Department of Surgery, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA; Division of Developmental Biology, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Samantha A Brugmann
- Division of Plastic Surgery, Department of Surgery, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA; Division of Developmental Biology, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA.
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29
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Kitao A, Matsui O, Yoneda N, Kozaka K, Kobayashi S, Koda W, Minami T, Inoue D, Yoshida K, Yamashita T, Yamashita T, Kaneko S, Takamura H, Ohta T, Ikeda H, Sato Y, Nakanuma Y, Harada K, Kita R, Gabata T. Gadoxetic acid-enhanced magnetic resonance imaging reflects co-activation of β-catenin and hepatocyte nuclear factor 4α in hepatocellular carcinoma. Hepatol Res 2018; 48:205-216. [PMID: 28488786 DOI: 10.1111/hepr.12911] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2017] [Revised: 05/04/2017] [Accepted: 05/08/2017] [Indexed: 02/08/2023]
Abstract
AIM The aim of this study is to clarify the correlation of the co-activation of β-catenin and hepatocyte nuclear factor (HNF)4α with the findings of gadoxetic acid-enhanced magnetic resonance imaging (MRI), organic anion transporting polypeptide (OATP)1B3 expression, and histological findings in hepatocellular carcinoma (HCC). METHODS One hundred and ninety-six HCCs surgically resected from 174 patients were enrolled in this study. The HCCs were classified into four groups by immunohistochemical expression of β-catenin, glutamine synthetase (GS), and HNF4α: (i) β-catenin/GS (positive [+]) HNF4α (+); (ii) β-catenin/GS (+) HNF4α (negative [-]); (iii) β-catenin/GS (-) HNF4α (+); and (iv) β-catenin/GS (-) HNF4α (-). We compared the four groups in terms of the enhancement ratio on the hepatobiliary phase of gadoxetic acid-enhanced MRI, immunohistochemical organic anion transporter polypeptide (OATP)1B3 (a main uptake transporter of gadoxetic acid) expression and histological features, overall survival, and no recurrence survival. The Kruskal-Wallis test, Steel-Dwass multiple comparisons test, Fisher's exact test, and log-rank (Mantel-Cox) test were used for statistical analyses. RESULTS Enhancement ratio on gadoxetic acid-enhanced MRI in HCC with β-catenin/GS (+) HNF4α (+) was significantly higher than those of the other three groups (P < 0.001). The OATP1B3 grade was also significantly higher in HCC with β-catenin/GS (+) HNF4α (+) (P < 0.001). Hepatocellular carcinoma with β-catenin/GS (+) HNF4α (+) showed the highest differentiation grade as compared to the other groups (P < 0.004). There were no significant differences in portal vein invasion, macroscopic growth pattern, or prognosis analyses between the four groups. CONCLUSION Co-activation of β-catenin and HNF4α would promote OATP1B3 expression, and consequently higher enhancement ratio on gadoxetic acid-enhanced MRI and higher differentiation grade in HCC.
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Affiliation(s)
- Azusa Kitao
- Department of Radiology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan
| | - Osamu Matsui
- Department of Radiology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan
| | - Norihide Yoneda
- Department of Radiology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan
| | - Kazuto Kozaka
- Department of Radiology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan
| | - Satoshi Kobayashi
- Department of Radiology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan
| | - Wataru Koda
- Department of Radiology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan
| | - Tetsuya Minami
- Department of Radiology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan
| | - Dai Inoue
- Department of Radiology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan
| | - Kotaro Yoshida
- Department of Radiology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan
| | - Taro Yamashita
- Department of Gastroenterology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan
| | - Tatsuya Yamashita
- Department of Gastroenterology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan
| | - Shuichi Kaneko
- Department of Gastroenterology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan
| | - Hiroyuki Takamura
- Department of Gaetroenterologic Surgery, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan
| | - Tetsuo Ohta
- Department of Gaetroenterologic Surgery, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan
| | - Hiroko Ikeda
- Department of Human Pathology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan
| | - Yasunori Sato
- Department of Human Pathology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan
| | - Yasuni Nakanuma
- Department of Human Pathology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan
| | - Kenichi Harada
- Department of Human Pathology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan
| | - Ryuichi Kita
- Department of Gastroenterology, Osaka Red Cross Hospital, Osaka, Japan
| | - Toshifumi Gabata
- Department of Radiology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan
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30
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Gao H, Wu B, Le Y, Zhu Z. Homeobox protein VentX induces p53-independent apoptosis in cancer cells. Oncotarget 2018; 7:39719-39729. [PMID: 27175592 PMCID: PMC5129965 DOI: 10.18632/oncotarget.9238] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 04/24/2016] [Indexed: 01/24/2023] Open
Abstract
Identifying novel tumor suppressors holds promise for improving cancer treatment. Our recent studies identified VentX, a homeobox transcriptional factor, as a putative tumor suppressor. Here we demonstrate that VentX exerts strong inhibitory effects on the proliferation and survival of cancer cells, but not primary transformed cells, such as 293T cells. Mechanistically, both in vitro and in vivo data showed that VentX induces apoptosis of cancer cells in a p53-independent manner. We found that VentX expression can be induced by chemotherapeutic agents. Taken together, our findings suggest that VentX may function as a novel therapeutic target in cancer treatment.
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Affiliation(s)
- Hong Gao
- Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, 02115, Massachusetts, USA.,Current address: Department of Medicine, Tufts Medical Center, Boston, 02115, Massachusetts, USA
| | - Bin Wu
- Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, 02115, Massachusetts, USA.,Current address: Department of Gastroenterology, Third Hospital, Sun Yat-Sen University, Guangzhou, 510630, China
| | - Yi Le
- Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, 02115, Massachusetts, USA
| | - Zhenglun Zhu
- Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, 02115, Massachusetts, USA
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31
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Ramakrishnan AB, Sinha A, Fan VB, Cadigan KM. The Wnt Transcriptional Switch: TLE Removal or Inactivation? Bioessays 2017; 40. [PMID: 29250807 DOI: 10.1002/bies.201700162] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Revised: 11/12/2017] [Indexed: 01/06/2023]
Abstract
Many targets of the Wnt/β-catenin signaling pathway are regulated by TCF transcription factors, which play important roles in animal development, stem cell biology, and oncogenesis. TCFs can regulate Wnt targets through a "transcriptional switch," repressing gene expression in unstimulated cells and promoting transcription upon Wnt signaling. However, it is not clear whether this switch mechanism is a general feature of Wnt gene regulation or limited to a subset of Wnt targets. Co-repressors of the TLE family are known to contribute to the repression of Wnt targets in the absence of signaling, but how they are inactivated or displaced by Wnt signaling is poorly understood. In this mini-review, we discuss several recent reports that address the prevalence and molecular mechanisms of the Wnt transcription switch, including the finding of Wnt-dependent ubiquitination/inactivation of TLEs. Together, these findings highlight the growing complexity of the regulation of gene expression by the Wnt pathway.
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Affiliation(s)
| | - Abhishek Sinha
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109-1048
| | - Vinson B Fan
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109-1048
| | - Ken M Cadigan
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109-1048
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32
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Shen P, Pichler M, Chen M, Calin GA, Ling H. To Wnt or Lose: The Missing Non-Coding Linc in Colorectal Cancer. Int J Mol Sci 2017; 18:ijms18092003. [PMID: 28930145 PMCID: PMC5618652 DOI: 10.3390/ijms18092003] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 09/09/2017] [Accepted: 09/13/2017] [Indexed: 02/06/2023] Open
Abstract
Colorectal cancer (CRC) is the third most frequent cancer and one of the leading causes for cancer-related mortality. Aberrant activation of the Wnt signaling is an essential initiating factor in colon carcinogenesis, and a driving force of CRC progression. Recently, long non-coding RNAs (lncRNAs) have emerged as significant players in CRC pathogenesis through diversified mechanisms. Although both Wnt signaling and lncRNAs represent interesting research areas for CRC, an effort of directly connecting these two areas is lacking. To fill in the knowledge gap, we focus on the reported findings of lncRNAs that regulate Wnt signaling or essential Wnt signaling targets. These include several newly discovered lncRNAs originated from the amplified cancer-associated chromosome 8q24 region that surrounds the essential Wnt target MYC gene, lncRNAs reported to be involved in CRC stem cells, and several individual lncRNAs connected to Wnt signaling through other mechanisms. This review will provide essential information that assists in understanding the missing link of lncRNAs to the classical Wnt signaling in CRC.
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Affiliation(s)
- Peng Shen
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
- Nanfang Hospital, Southern Medical University/The First School of Clinical Medicine, Southern Medical University, Guangzhou 510515, Guangdong, China.
| | - Martin Pichler
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
- Research Unit of Non-Coding RNA and Genome Editing in Cancer, Division of Oncology, Medical University of Graz, Graz 8010, Austria.
| | - Meng Chen
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
| | - George A Calin
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
- The Center for RNA Interference and Non-Coding RNAs, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
| | - Hui Ling
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
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Kim K, Cho J, Hilzinger TS, Nunns H, Liu A, Ryba BE, Goentoro L. Two-Element Transcriptional Regulation in the Canonical Wnt Pathway. Curr Biol 2017; 27:2357-2364.e5. [PMID: 28756947 DOI: 10.1016/j.cub.2017.06.037] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Revised: 06/02/2017] [Accepted: 06/14/2017] [Indexed: 12/25/2022]
Abstract
The canonical Wnt pathway regulates numerous fundamental processes throughout development and adult physiology and is often disrupted in diseases [1-4]. Signal in the pathway is transduced by β-catenin, which in complex with Tcf/Lef regulates transcription. Despite the many processes that the Wnt pathway governs, β-catenin acts primarily on a single cis element in the DNA, the Wnt-responsive element (WRE), at times potentiated by a nearby Helper site. In this study, working with Xenopus, mouse, and human systems, we identified a cis element, distinct from WRE, upon which β-catenin and Tcf act. The element is 11 bp long, hundreds of bases apart from the WRE, and exhibits a suppressive effect. In Xenopus patterning, loss of the 11-bp negative regulatory elements (11-bp NREs) broadened dorsal expression of siamois. In mouse embryonic stem cells, genomic deletion of the 11-bp NREs in the promoter elevated Brachyury expression. This reveals a previously unappreciated mechanism within the Wnt pathway, where gene response is not only driven by WREs but also tuned by 11-bp NREs. Using electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP), we found evidence for the NREs binding to β-catenin and Tcf-suggesting a dual action by β-catenin as a signal and a feedforward sensor. Analyzing β-catenin ChIP sequencing in human cells, we found the 11-bp NREs co-localizing with the WRE in 45%-71% of the peaks, suggesting a widespread role for the mechanism. This study presents an example of a more complex cis regulation by a signaling pathway, where a signal is processed through two distinct cis elements in a gene circuitry.
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Affiliation(s)
- Kibeom Kim
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Jaehyoung Cho
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Thomas S Hilzinger
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Harry Nunns
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Andrew Liu
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Bryan E Ryba
- Department of Physics and Department of Molecular Biology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Lea Goentoro
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA.
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Epidermal E-Cadherin Dependent β-Catenin Pathway Is Phytochemical Inducible and Accelerates Anagen Hair Cycling. Mol Ther 2017; 25:2502-2512. [PMID: 28803863 DOI: 10.1016/j.ymthe.2017.07.010] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 07/06/2017] [Accepted: 07/16/2017] [Indexed: 01/29/2023] Open
Abstract
Unlike the epidermis, which regenerates continually, hair follicles anchored in the subcutis periodically regenerate by spontaneous repetitive cycles of growth (anagen), degeneration (catagen), and rest (telogen). The loss of hair follicles in response to injuries or pathologies such as alopecia endangers certain inherent functions of the skin. Thus, it is of interest to understand mechanisms underlying follicular regeneration in adults. In this work, a phytochemical rich in the natural vitamin E tocotrienol (TRF) served as a productive tool to unveil a novel epidermal pathway of hair follicular regeneration. Topical TRF application markedly induced epidermal hair follicle development akin to that during fetal skin development. This was observed in the skin of healthy as well as diabetic mice, which are known to be resistant to anagen hair cycling. TRF suppressed epidermal E-cadherin followed by 4-fold induction of β-catenin and its nuclear translocation. Nuclear β-catenin interacted with Tcf3. Such sequestration of Tcf3 from its otherwise known function to repress pluripotent factors induced the plasticity factors Oct4, Sox9, Klf4, c-Myc, and Nanog. Pharmacological inhibition of β-catenin arrested anagen hair cycling by TRF. This work reports epidermal E-cadherin/β-catenin as a novel pathway capable of inducing developmental folliculogenesis in the adult skin.
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Identification and comparative analyses of Siamois cluster genes in Xenopus laevis and tropicalis. Dev Biol 2017; 426:374-383. [PMID: 27522305 DOI: 10.1016/j.ydbio.2016.07.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Revised: 07/13/2016] [Accepted: 07/16/2016] [Indexed: 11/21/2022]
Abstract
Two siamois-related homeobox genes siamois (sia1) and twin (sia2), have been reported in Xenopus laevis. These genes are expressed in the blastula chordin- and noggin-expressing (BCNE) center and the Nieuwkoop center, and have complete secondary axis-inducing activity when over-expressed on the ventral side of the embryo. Using whole genome sequences of X. tropicalis and X. laevis, we identified two additional siamois-related genes, which are tandemly duplicated near sia1 and sia2 to form the siamois gene cluster. Four siamois genes in X. tropicalis are transcribed at blastula to gastrula stages. In X. laevis, the siamois gene cluster is present on both homeologous chromosomes, XLA3L and XLA3S. Transcripts from seven siamois genes (three on XLA3L and four on XLA3S) in X. laevis were detected at blastula to gastrula stages. A transcribed gene, sia1p. S, encodes an inactive protein without a homeodomain. When over-expressed ventrally, all siamois-related genes tested in this study except for sia1p. S induced a complete secondary axis, indicating that X. tropicalis and X. laevis have four and six active siamois-related genes, respectively. Of note, each gene required different amounts of mRNA for full activity. These results suggest the possibility that siamois cluster genes have functional redundancy to endow robustness and quickness to organizer formation in Xenopus species.
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36
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Nakamura Y, Hoppler S. Genome-wide analysis of canonical Wnt target gene regulation in Xenopus tropicalis challenges β-catenin paradigm. Genesis 2017; 55. [PMID: 28095618 PMCID: PMC5299483 DOI: 10.1002/dvg.22991] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Accepted: 10/30/2016] [Indexed: 12/20/2022]
Abstract
Wnt/β‐catenin signaling is an important cell‐to‐cell signaling mechanism that controls gene expression during embryonic development and is critically implicated in human diseases. Developmental, cellular, and transcriptional responses to Wnt signaling are remarkably context‐specific in different biological processes. While nuclear localization of β‐catenin is the key to activation of the Wnt/β‐catenin pathway and target gene expression, the molecular mechanisms of how the same Wnt/β‐catenin signaling pathway induces specific responses remain undetermined. Recent advances in high‐throughput sequencing technologies and the availability of genome information for Xenopus tropicalis have enabled us to uncover a genome‐wide view of Wnt/β‐catenin signaling in early vertebrate embryos, which challenges previous concepts about molecular mechanisms of Wnt target gene regulation. In this review, we summarize our experimental approaches, introduce the technologies we employed and focus on recent findings about Wnt target gene regulation from Xenopus research. We will also discuss potential functions of widespread β‐catenin binding in the genome that we discovered in this species.
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Affiliation(s)
- Yukio Nakamura
- Institute of Medical Sciences, Foresterhill Health Campus, University of Aberdeen, Aberdeen, AB25 2ZD, United Kingdom
| | - Stefan Hoppler
- Institute of Medical Sciences, Foresterhill Health Campus, University of Aberdeen, Aberdeen, AB25 2ZD, United Kingdom
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37
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HER2 in Breast Cancer Stemness: A Negative Feedback Loop towards Trastuzumab Resistance. Cancers (Basel) 2017; 9:cancers9050040. [PMID: 28445439 PMCID: PMC5447950 DOI: 10.3390/cancers9050040] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Revised: 04/10/2017] [Accepted: 04/21/2017] [Indexed: 12/19/2022] Open
Abstract
HER2 receptor tyrosine kinase that is overexpressed in approximately 20% of all breast cancers (BCs) is a poor prognosis factor and a precious target for BC therapy. Trastuzumab is approved by FDA to specifically target HER2 for treating HER2+ BC. However, about 60% of patients with HER2+ breast tumor develop de novo resistance to trastuzumab, partially due to the loss of expression of HER2 extracellular domain on their tumor cells. This is due to shedding/cleavage of HER2 by metalloproteinases (ADAMs and MMPs). HER2 shedding results in the accumulation of intracellular carboxyl-terminal HER2 (p95HER2), which is a common phenomenon in trastuzumab-resistant tumors and is suggested as a predictive marker for trastuzumab resistance. Up-regulation of the metalloproteinases is a poor prognosis factor and is commonly seen in mesenchymal-like cancer stem cells that are risen during epithelial to mesenchymal transition (EMT) of tumor cells. HER2 cleavage during EMT can explain why secondary metastatic tumors with high percentage of mesenchymal-like cancer stem cells are mostly resistant to trastuzumab but still sensitive to lapatinib. Importantly, many studies report HER2 interaction with oncogenic/stemness signaling pathways including TGF-β/Smad, Wnt/β-catenin, Notch, JAK/STAT and Hedgehog. HER2 overexpression promotes EMT and the emergence of cancer stem cell properties in BC. Increased expression and activation of metalloproteinases during EMT leads to proteolytic cleavage and shedding of HER2 receptor, which downregulates HER2 extracellular domain and eventually increases trastuzumab resistance. Here, we review the hypothesis that a negative feedback loop between HER2 and stemness signaling drives resistance of BC to trastuzumab.
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38
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Franz A, Shlyueva D, Brunner E, Stark A, Basler K. Probing the canonicity of the Wnt/Wingless signaling pathway. PLoS Genet 2017; 13:e1006700. [PMID: 28369070 PMCID: PMC5393890 DOI: 10.1371/journal.pgen.1006700] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Revised: 04/17/2017] [Accepted: 03/15/2017] [Indexed: 02/02/2023] Open
Abstract
The hallmark of canonical Wnt signaling is the transcriptional induction of Wnt target genes by the beta-catenin/TCF complex. Several studies have proposed alternative interaction partners for beta-catenin or TCF, but the relevance of potential bifurcations in the distal Wnt pathway remains unclear. Here we study on a genome-wide scale the requirement for Armadillo (Arm, Drosophila beta-catenin) and Pangolin (Pan, Drosophila TCF) in the Wnt/Wingless(Wg)-induced transcriptional response of Drosophila Kc cells. Using somatic genetics, we demonstrate that both Arm and Pan are absolutely required for mediating activation and repression of target genes. Furthermore, by means of STARR-sequencing we identified Wnt/Wg-responsive enhancer elements and found that all responsive enhancers depend on Pan. Together, our results confirm the dogma of canonical Wnt/Wg signaling and argue against the existence of distal pathway branches in this system. Our manuscript addresses the question of whether either of the canonical transduction components, beta-catenin or TCF, can be bypassed when the Wnt pathway is activated. By using somatic cell genetics in Drosophila cells (via CRISPR/Cas9 editing) in combination with RNA-seq and STARR-seq (Self-transcribing-active-regulatory-region-sequencing) as functional read-outs, we provide firm evidence against the existence of distal branches in the Wnt pathway.
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Affiliation(s)
- Alexandra Franz
- Institute of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Daria Shlyueva
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Campus-Vienna-Biocenter 1, Vienna, Austria
| | - Erich Brunner
- Institute of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Alexander Stark
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Campus-Vienna-Biocenter 1, Vienna, Austria
| | - Konrad Basler
- Institute of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
- * E-mail:
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Charney RM, Paraiso KD, Blitz IL, Cho KWY. A gene regulatory program controlling early Xenopus mesendoderm formation: Network conservation and motifs. Semin Cell Dev Biol 2017; 66:12-24. [PMID: 28341363 DOI: 10.1016/j.semcdb.2017.03.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Revised: 03/12/2017] [Accepted: 03/20/2017] [Indexed: 02/08/2023]
Abstract
Germ layer formation is among the earliest differentiation events in metazoan embryos. In triploblasts, three germ layers are formed, among which the endoderm gives rise to the epithelial lining of the gut tube and associated organs including the liver, pancreas and lungs. In frogs (Xenopus), where early germ layer formation has been studied extensively, the process of endoderm specification involves the interplay of dozens of transcription factors. Here, we review the interactions between these factors, summarized in a transcriptional gene regulatory network (GRN). We highlight regulatory connections conserved between frog, fish, mouse, and human endodermal lineages. Especially prominent is the conserved role and regulatory targets of the Nodal signaling pathway and the T-box transcription factors, Vegt and Eomes. Additionally, we highlight network topologies and motifs, and speculate on their possible roles in development.
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Affiliation(s)
- Rebekah M Charney
- Department of Developmental and Cell Biology, Ayala School of Biological Sciences, University of California, Irvine, CA 92697, USA
| | - Kitt D Paraiso
- Department of Developmental and Cell Biology, Ayala School of Biological Sciences, University of California, Irvine, CA 92697, USA
| | - Ira L Blitz
- Department of Developmental and Cell Biology, Ayala School of Biological Sciences, University of California, Irvine, CA 92697, USA
| | - Ken W Y Cho
- Department of Developmental and Cell Biology, Ayala School of Biological Sciences, University of California, Irvine, CA 92697, USA.
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40
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Ubiquitin C-terminal hydrolase37 regulates Tcf7 DNA binding for the activation of Wnt signalling. Sci Rep 2017; 7:42590. [PMID: 28198400 PMCID: PMC5309806 DOI: 10.1038/srep42590] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 01/11/2017] [Indexed: 12/18/2022] Open
Abstract
The Tcf/Lef family of transcription factors mediates the Wnt/β-catenin pathway that is involved in a wide range of biological processes, including vertebrate embryogenesis and diverse pathogenesis. Post-translational modifications, including phosphorylation, sumoylation and acetylation, are known to be important for the regulation of Tcf/Lef proteins. However, the importance of ubiquitination and ubiquitin-mediated regulatory mechanisms for Tcf/Lef activity are still unclear. Here, we newly show that ubiquitin C-terminal hydrolase 37 (Uch37), a deubiquitinase, interacts with Tcf7 (formerly named Tcf1) to activate Wnt signalling. Biochemical analyses demonstrated that deubiquitinating activity of Uch37 is not involved in Tcf7 protein stability but is required for the association of Tcf7 to target gene promoter in both Xenopus embryo and human liver cancer cells. In vivo analyses further revealed that Uch37 functions as a positive regulator of the Wnt/β-catenin pathway downstream of β-catenin stabilization that is required for the expression of ventrolateral mesoderm genes during Xenopus gastrulation. Our study provides a new mechanism for chromatin occupancy of Tcf7 and uncovers the physiological significance of Uch37 during early vertebrate development by regulating the Wnt/β-catenin pathway.
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Houston DW. Vertebrate Axial Patterning: From Egg to Asymmetry. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 953:209-306. [PMID: 27975274 PMCID: PMC6550305 DOI: 10.1007/978-3-319-46095-6_6] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The emergence of the bilateral embryonic body axis from a symmetrical egg has been a long-standing question in developmental biology. Historical and modern experiments point to an initial symmetry-breaking event leading to localized Wnt and Nodal growth factor signaling and subsequent induction and formation of a self-regulating dorsal "organizer." This organizer forms at the site of notochord cell internalization and expresses primarily Bone Morphogenetic Protein (BMP) growth factor antagonists that establish a spatiotemporal gradient of BMP signaling across the embryo, directing initial cell differentiation and morphogenesis. Although the basics of this model have been known for some time, many of the molecular and cellular details have only recently been elucidated and the extent that these events remain conserved throughout vertebrate evolution remains unclear. This chapter summarizes historical perspectives as well as recent molecular and genetic advances regarding: (1) the mechanisms that regulate symmetry-breaking in the vertebrate egg and early embryo, (2) the pathways that are activated by these events, in particular the Wnt pathway, and the role of these pathways in the formation and function of the organizer, and (3) how these pathways also mediate anteroposterior patterning and axial morphogenesis. Emphasis is placed on comparative aspects of the egg-to-embryo transition across vertebrates and their evolution. The future prospects for work regarding self-organization and gene regulatory networks in the context of early axis formation are also discussed.
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Affiliation(s)
- Douglas W Houston
- Department of Biology, The University of Iowa, 257 BB, Iowa City, IA, 52242, USA.
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Gillis WQ, Kirmizitas A, Iwasaki Y, Ki DH, Wyrick JM, Thomsen GH. Gtpbp2 is a positive regulator of Wnt signaling and maintains low levels of the Wnt negative regulator Axin. Cell Commun Signal 2016; 14:15. [PMID: 27484226 PMCID: PMC4969687 DOI: 10.1186/s12964-016-0138-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 07/29/2016] [Indexed: 12/29/2022] Open
Abstract
Background Canonical Wnt signals, transduced by stabilized β-catenin, play similar roles across animals in maintaining stem cell pluripotency, regulating cell differentiation, and instructing normal embryonic development. Dysregulated Wnt/β-catenin signaling causes diseases and birth defects, and a variety of regulatory processes control this pathway to ensure its proper function and integration with other signaling systems. We previously identified GTP-binding protein 2 (Gtpbp2) as a novel regulator of BMP signaling, however further exploration revealed that Gtpbp2 can also affect Wnt signaling, which is a novel finding reported here. Results Knockdown of Gtpbp2 in Xenopus embryos causes severe axial defects and reduces expression of Spemann-Mangold organizer genes. Gtpbp2 knockdown blocks responses to ectopic Wnt8 ligand, such as organizer gene induction in ectodermal tissue explants and induction of secondary axes in whole embryos. However, organizer gene induction by ectopic Nodal2 is unaffected by Gtpbp2 knockdown. Epistasis tests, conducted by activating Wnt signal transduction at sequential points in the canonical pathway, demonstrate that Gtpbp2 is required downstream of Dishevelled and Gsk3β but upstream of β-catenin, which is similar to the previously reported effects of Axin1 overexpression in Xenopus embryos. Focusing on Axin in Xenopus embryos, we find that knockdown of Gtpbp2 elevates endogenous or exogenous Axin protein levels. Furthermore, Gtpbp2 fusion proteins co-localize with Dishevelled and co-immunoprecipitate with Axin and Gsk3b. Conclusions We conclude that Gtpbp2 is required for canonical Wnt/β-catenin signaling in Xenopus embryos. Our data suggest a model in which Gtpbp2 suppresses the accumulation of Axin protein, a rate-limiting component of the β-catenin destruction complex, such that Axin protein levels negatively correlate with Gtpbp2 levels. This model is supported by the similarity of our Gtpbp2-Wnt epistasis results and previously reported effects of Axin overexpression, the physical interactions of Gtpbp2 with Axin, and the correlation between elevated Axin protein levels and lost Wnt responsiveness upon Gtpbp2 knockdown. A wide variety of cancer-causing Wnt pathway mutations require low Axin levels, so development of Gtpbp2 inhibitors may provide a new therapeutic strategy to elevate Axin and suppress aberrant β-catenin signaling in cancer and other Wnt-related diseases. Electronic supplementary material The online version of this article (doi:10.1186/s12964-016-0138-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- William Q Gillis
- Department of Biochemistry and Cell Biology, Graduate Program in Molecular and Cellular Biology, Center for Developmental Genetics, Stony Brook University, Stony Brook, NY, 11794-5215, USA.,Present Address: Department of Biological Sciences, State University of New York, College at Old Westbury, Old Westbury, NY, 11568, USA
| | - Arif Kirmizitas
- Department of Biochemistry and Cell Biology, Graduate Program in Molecular and Cellular Biology, Center for Developmental Genetics, Stony Brook University, Stony Brook, NY, 11794-5215, USA.,Present Address: The Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Headington, Oxford, OX3 9DS, UK
| | - Yasuno Iwasaki
- Department of Biochemistry and Cell Biology, Graduate Program in Molecular and Cellular Biology, Center for Developmental Genetics, Stony Brook University, Stony Brook, NY, 11794-5215, USA
| | - Dong-Hyuk Ki
- Department of Biochemistry and Cell Biology, Graduate Program in Molecular and Cellular Biology, Center for Developmental Genetics, Stony Brook University, Stony Brook, NY, 11794-5215, USA.,Present Address: Department of Pediatric Oncology, Dana-Farber Cancer Institute, Division of Hematology/Oncology, Children's Hospital Boston, Harvard Medical School, Boston, MA, USA
| | - Jonathan M Wyrick
- Department of Biochemistry and Cell Biology, Graduate Program in Molecular and Cellular Biology, Center for Developmental Genetics, Stony Brook University, Stony Brook, NY, 11794-5215, USA
| | - Gerald H Thomsen
- Department of Biochemistry and Cell Biology, Graduate Program in Molecular and Cellular Biology, Center for Developmental Genetics, Stony Brook University, Stony Brook, NY, 11794-5215, USA.
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Hrckulak D, Kolar M, Strnad H, Korinek V. TCF/LEF Transcription Factors: An Update from the Internet Resources. Cancers (Basel) 2016; 8:cancers8070070. [PMID: 27447672 PMCID: PMC4963812 DOI: 10.3390/cancers8070070] [Citation(s) in RCA: 98] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 07/11/2016] [Accepted: 07/14/2016] [Indexed: 12/18/2022] Open
Abstract
T-cell factor/lymphoid enhancer-binding factor (TCF/LEF) proteins (TCFs) from the High Mobility Group (HMG) box family act as the main downstream effectors of the Wnt signaling pathway. The mammalian TCF/LEF family comprises four nuclear factors designated TCF7, LEF1, TCF7L1, and TCF7L2 (also known as TCF1, LEF1, TCF3, and TCF4, respectively). The proteins display common structural features and are often expressed in overlapping patterns implying their redundancy. Such redundancy was indeed observed in gene targeting studies; however, individual family members also exhibit unique features that are not recapitulated by the related proteins. In the present viewpoint, we summarized our current knowledge about the specific features of individual TCFs, namely structural-functional studies, posttranslational modifications, interacting partners, and phenotypes obtained upon gene targeting in the mouse. In addition, we employed several publicly available databases and web tools to evaluate the expression patterns and production of gene-specific isoforms of the TCF/LEF family members in human cells and tissues.
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Affiliation(s)
- Dusan Hrckulak
- Department of Cell and Developmental Biology, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Videnska 1083, Prague 4 14220, Czech Republic.
| | - Michal Kolar
- Department of Genomics and Bioinformatics, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Videnska 1083, Prague 4 14220, Czech Republic.
| | - Hynek Strnad
- Department of Genomics and Bioinformatics, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Videnska 1083, Prague 4 14220, Czech Republic.
| | - Vladimir Korinek
- Department of Cell and Developmental Biology, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Videnska 1083, Prague 4 14220, Czech Republic.
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Thymosin β4 impeded murine stem cell proliferation with an intact cardiovascular differentiation. ACTA ACUST UNITED AC 2016; 36:328-334. [PMID: 27376799 DOI: 10.1007/s11596-016-1587-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 03/30/2016] [Indexed: 12/22/2022]
Abstract
Thymosin β4 (Tβ4) is a key factor in cardiac development, growth, disease, epicardial integrity, blood vessel formation and has cardio-protective properties. However, its role in murine embryonic stem cells (mESCs) proliferation and cardiovascular differentiation remains unclear. Thus we aimed to elucidate the influence of Tβ4 on mESCs. Target genes during mESCs proliferation and differentiation were detected by real-time PCR or Western blotting, and patch clamp was applied to characterize the mESCs-derived cardiomyocytes. It was found that Tβ4 decreased mESCs proliferation in a partial dose-dependent manner and the expression of cell cycle regulatory genes c-myc, c-fos and c-jun. However, mESCs self-renewal markers Oct4 and Nanog were elevated, indicating the maintenance of self-renewal ability in these mESCs. Phosphorylation of STAT3 and Akt was inhibited by Tβ4 while the expression of RAS and phosphorylation of ERK were enhanced. No significant difference was found in BMP2/BMP4 or their downstream protein smad. Wnt3 and Wnt11 were remarkably decreased by Tβ4 with upregulation of Tcf3 and constant β-catenin. Under mESCs differentiation, Tβ4 treatment did not change the expression of cardiovascular cell markers α-MHC, PECAM, and α-SMA. Neither the electrophysiological properties of mESCs-derived cardiomyocytes nor the hormonal regulation by Iso/Cch was affected by Tβ4. In conclusion, Tβ4 suppressed mESCs proliferation by affecting the activity of STAT3, Akt, ERK and Wnt pathways. However, Tβ4 did not influence the in vitro cardiovascular differentiation.
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Jin T. Current Understanding on Role of the Wnt Signaling Pathway Effector TCF7L2 in Glucose Homeostasis. Endocr Rev 2016; 37:254-77. [PMID: 27159876 DOI: 10.1210/er.2015-1146] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The role of the Wnt signaling pathway in metabolic homeostasis has drawn our intensive attention, especially after the genome-wide association study discovery that certain polymorphisms of its key effector TCF7L2 are strongly associated with the susceptibility to type 2 diabetes. For a decade, great efforts have been made in determining the function of TCF7L2 in various metabolic organs, which have generated both considerable achievements and disputes. In this review, I will briefly introduce the canonical Wnt signaling pathway, focusing on its effector β-catenin/TCF, including emphasizing the bidirectional feature of TCFs and β-catenin post-translational modifications. I will then summarize the observations on the association between TCF7L2 polymorphisms and type 2 diabetes risk. The main content, however, is on the intensive functional exploration of the metabolic role of TCF7L2, including the disputes generated on determining its role in the pancreas and liver with various transgenic mouse lines. Finally, I will discuss those achievements and disputes and present my future perspectives.
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Affiliation(s)
- Tianru Jin
- Division of Advanced Diagnostics, Toronto General Research Institute, University Health Network, Toronto, ON M5G 2C4, Canada
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Nakamura Y, de Paiva Alves E, Veenstra GJC, Hoppler S. Tissue- and stage-specific Wnt target gene expression is controlled subsequent to β-catenin recruitment to cis-regulatory modules. Development 2016; 143:1914-25. [PMID: 27068107 PMCID: PMC4920159 DOI: 10.1242/dev.131664] [Citation(s) in RCA: 93] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Accepted: 03/31/2016] [Indexed: 12/20/2022]
Abstract
Key signalling pathways, such as canonical Wnt/β-catenin signalling, operate repeatedly to regulate tissue- and stage-specific transcriptional responses during development. Although recruitment of nuclear β-catenin to target genomic loci serves as the hallmark of canonical Wnt signalling, mechanisms controlling stage- or tissue-specific transcriptional responses remain elusive. Here, a direct comparison of genome-wide occupancy of β-catenin with a stage-matched Wnt-regulated transcriptome reveals that only a subset of β-catenin-bound genomic loci are transcriptionally regulated by Wnt signalling. We demonstrate that Wnt signalling regulates β-catenin binding to Wnt target genes not only when they are transcriptionally regulated, but also in contexts in which their transcription remains unaffected. The transcriptional response to Wnt signalling depends on additional mechanisms, such as BMP or FGF signalling for the particular genes we investigated, which do not influence β-catenin recruitment. Our findings suggest a more general paradigm for Wnt-regulated transcriptional mechanisms, which is relevant for tissue-specific functions of Wnt/β-catenin signalling in embryonic development but also for stem cell-mediated homeostasis and cancer. Chromatin association of β-catenin, even to functional Wnt-response elements, can no longer be considered a proxy for identifying transcriptionally Wnt-regulated genes. Context-dependent mechanisms are crucial for transcriptional activation of Wnt/β-catenin target genes subsequent to β-catenin recruitment. Our conclusions therefore also imply that Wnt-regulated β-catenin binding in one context can mark Wnt-regulated transcriptional target genes for different contexts. Highlighted article: Dual ChIP-seq and RNA-seq in vivo experiments show that the context-specific events that occur subsequent to β-catenin binding enable gene-specific regulation, rather than β-catenin recruitment per se.
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Affiliation(s)
- Yukio Nakamura
- Institute of Medical Sciences, Foresterhill Health Campus, University of Aberdeen, Aberdeen AB25 2ZD, UK
| | - Eduardo de Paiva Alves
- Centre for Genome-Enabled Biology and Medicine, University of Aberdeen, Aberdeen AB24 3RY, UK
| | - Gert Jan C Veenstra
- Radboud University, Department of Molecular Developmental Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, 6500 HB Nijmegen, The Netherlands
| | - Stefan Hoppler
- Institute of Medical Sciences, Foresterhill Health Campus, University of Aberdeen, Aberdeen AB25 2ZD, UK
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Niu Q, Li F, Zhang L, Xu X, Liu Y, Gao J, Feng X. Role of the Wnt/β-catenin signaling pathway in the response of chondrocytes to mechanical loading. Int J Mol Med 2016; 37:755-62. [PMID: 26821383 DOI: 10.3892/ijmm.2016.2463] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Accepted: 01/05/2016] [Indexed: 11/05/2022] Open
Abstract
In order to better understand the mechanisms by which chondrocytes respond to mechanical stimulation, ATDC5 mouse embryonic carcinoma cells were induced to differentiate into chondrocytes and then exposed to mechanical loading. To specifically elucidate the role of this pathway, the localization and expression of proteins involved in the Wnt/β-catenin signaling pathway were observed. Chondrogenic-differentiated ATDC5 cells were exposed to a 12% cycle tension load for 1, 2, 4, or 8 h. At each time point, immunofluorescence staining, western blot analysis, and qPCR were used to track the localization of β-catenin and glycogen synthase kinase-3β (GSK-3β) expression. In addition, the mRNA expression of Wnt3a, disheveled homolog 1 (Dvl-1), GSK-3β, and collagen type II were also detected. Activation of the Wnt/β-catenin signaling pathway was investigated in cells treated with Dickkopf-related protein 1 (DKK-1). β-catenin and GSK-3β protein expression increased initially and then decreased over the mechanical loading period, and the corresponding mRNA levels followed a similar trend. After application of the inhibitor DKK-1, Wnt/β‑catenin signaling was suppressed, and the mRNA expression of collagen II was also reduced. Thus, stimulation of chondrocytes with mechanical strain loading is associated with the translocation of active β-catenin from the cytoplasm to the nucleus.
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Affiliation(s)
- Qiannan Niu
- State Key Laboratory of Military Stomatology, Department of Orthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Feifei Li
- State Key Laboratory of Military Stomatology, Department of Orthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Liang Zhang
- Department of Stomatology, Hospital 323 of The People's Liberation Army, Xi'an, Shaanxi 710045, P.R. China
| | - Xinyuan Xu
- Department of Biochemistry and Molecular Biology, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Yucong Liu
- Department of Stomatology, The First People's Hospital of Shuangliu County, Chengdu, Sichuan 610200, P.R. China
| | - Jie Gao
- State Key Laboratory of Military Stomatology, Department of Orthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Xue Feng
- State Key Laboratory of Military Stomatology, Department of Orthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
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Wnt/β-catenin signaling plays an ever-expanding role in stem cell self-renewal, tumorigenesis and cancer chemoresistance. Genes Dis 2016; 3:11-40. [PMID: 27077077 PMCID: PMC4827448 DOI: 10.1016/j.gendis.2015.12.004] [Citation(s) in RCA: 198] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Wnt signaling transduces evolutionarily conserved pathways which play important roles in initiating and regulating a diverse range of cellular activities, including cell proliferation, calcium homeostasis, and cell polarity. The role of Wnt signaling in controlling cell proliferation and stem cell self-renewal is primarily carried out through the canonical pathway, which is the best-characterized the multiple Wnt signaling branches. The past 10 years has seen a rapid expansion in our understanding of the complexity of this pathway, as many new components of Wnt signaling have been identified and linked to signaling regulation, stem cell functions, and adult tissue homeostasis. Additionally, a substantial body of evidence links Wnt signaling to tumorigenesis of cancer types and implicates it in the development of cancer drug resistance. Thus, a better understanding of the mechanisms by which dysregulation of Wnt signaling precedes the development and progression of human cancer may hasten the development of pathway inhibitors to augment current therapy. This review summarizes and synthesizes our current knowledge of the canonical Wnt pathway in development and disease. We begin with an overview of the components of the canonical Wnt signaling pathway and delve into the role this pathway has been shown to play in stemness, tumorigenesis, and cancer drug resistance. Ultimately, we hope to present an organized collection of evidence implicating Wnt signaling in tumorigenesis and chemoresistance to facilitate the pursuit of Wnt pathway modulators that may improve outcomes of cancers in which Wnt signaling contributes to aggressive disease and/or treatment resistance.
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A novel role for the tumour suppressor Nitrilase1 modulating the Wnt/β-catenin signalling pathway. Cell Discov 2016; 2:15039. [PMID: 27462437 PMCID: PMC4860965 DOI: 10.1038/celldisc.2015.39] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Accepted: 10/08/2015] [Indexed: 02/07/2023] Open
Abstract
Nitrilase1 was classified as a tumour suppressor in association with the fragile histidine-triad protein Fhit. However, knowledge about nitrilase1 and its tumour suppressor function is still limited. Whereas nitrilase1 and Fhit are discrete proteins in mammals, they are merged in Drosophila melanogaster and Caenorhabditis elegans. According to the Rosetta-Stone hypothesis, proteins encoded as fusion proteins in one organism and as separate proteins in another organism may act in the same signalling pathway. Although a direct interaction of human nitrilase1 and Fhit has not been shown, our previous finding that Fhit interacts with β-catenin and represses its transcriptional activity in the canonical Wnt pathway suggested that human nitrilase1 also modulates Wnt signalling. In fact, human nitrilase1 forms a complex with β-catenin and LEF-1/TCF-4, represses β-catenin-mediated transcription and shows an additive effect together with Fhit. Knockdown of human nitrilase1 enhances Wnt target gene expression. Moreover, our experiments show that β-catenin competes away human nitrilase1 from LEF-1/TCF and thereby contributes to the activation of Wnt-target gene transcription. Inhibitory activity of human nitrilase1 on vertebrate Wnt signalling was confirmed by repression of Wnt-induced double axis formation in Xenopus embryogenesis. In line with this finding, the Drosophila fusion protein Drosophila NitFhit directly binds to Armadillo and represses the Wingless pathway in reporter gene assays. Genetic experiments confirmed the repressive activity of Drosophila NitFhit on Wingless signalling in the Drosophila wing imaginal disc. In addition, colorectal tumour microarray analysis revealed a significantly reduced expression of human nitrilase1 in poorly differentiated tumours. Taken together, repression of the canonical Wnt pathway represents a new mechanism for the human nitrilase1 tumour suppressor function.
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Abstract
β-catenin is widely regarded as the primary transducer of canonical WNT signals to the nucleus. In most vertebrates, there are eight additional catenins that are structurally related to β-catenin, and three α-catenin genes encoding actin-binding proteins that are structurally related to vinculin. Although these catenins were initially identified in association with cadherins at cell-cell junctions, more recent evidence suggests that the majority of catenins also localize to the nucleus and regulate gene expression. Moreover, the number of catenins reported to be responsive to canonical WNT signals is increasing. Here, we posit that multiple catenins form a functional network in the nucleus, possibly engaging in conserved protein-protein interactions that are currently better characterized in the context of actin-based cell junctions.
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