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Sachan N, Sharma V, Mutsuddi M, Mukherjee A. Notch signalling: multifaceted role in development and disease. FEBS J 2024; 291:3030-3059. [PMID: 37166442 DOI: 10.1111/febs.16815] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 02/08/2023] [Accepted: 05/10/2023] [Indexed: 05/12/2023]
Abstract
Notch pathway is an evolutionarily conserved signalling system that operates to influence an astonishing array of cell fate decisions in different developmental contexts. Notch signalling plays important roles in many developmental processes, making it difficult to name a tissue or a developing organ that does not depend on Notch function at one stage or another. Thus, dysregulation of Notch signalling is associated with many developmental defects and various pathological conditions, including cancer. Although many recent advances have been made to reveal different aspects of the Notch signalling mechanism and its intricate regulation, there are still many unanswered questions related to how the Notch signalling pathway functions in so many developmental events. The same pathway can be deployed in numerous cellular contexts to play varied and critical roles in an organism's development and this is only possible because of the complex regulatory mechanisms of the pathway. In this review, we provide an overview of the mechanism and regulation of the Notch signalling pathway along with its multifaceted functions in different aspects of development and disease.
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Affiliation(s)
- Nalani Sachan
- Department of Molecular and Human Genetics, Institute of Science, Banaras Hindu University, Varanasi, India
- Department of Cell Biology, NYU Grossman School of Medicine, New York, NY, USA
| | - Vartika Sharma
- Department of Molecular and Human Genetics, Institute of Science, Banaras Hindu University, Varanasi, India
| | - Mousumi Mutsuddi
- Department of Molecular and Human Genetics, Institute of Science, Banaras Hindu University, Varanasi, India
| | - Ashim Mukherjee
- Department of Molecular and Human Genetics, Institute of Science, Banaras Hindu University, Varanasi, India
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2
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Tveriakhina L, Scanavachi G, Egan ED, Da Cunha Correia RB, Martin AP, Rogers JM, Yodh JS, Aster JC, Kirchhausen T, Blacklow SC. Temporal dynamics and stoichiometry in human Notch signaling from Notch synaptic complex formation to nuclear entry of the Notch intracellular domain. Dev Cell 2024; 59:1425-1438.e8. [PMID: 38574735 DOI: 10.1016/j.devcel.2024.03.021] [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: 10/05/2023] [Revised: 01/10/2024] [Accepted: 03/11/2024] [Indexed: 04/06/2024]
Abstract
Mammalian Notch signaling occurs when the binding of Delta or Jagged to Notch stimulates the proteolytic release of the Notch intracellular domain (NICD), which enters the nucleus to control target gene expression. To determine the temporal dynamics of events associated with Notch signaling under native conditions, we fluorescently tagged Notch and Delta at their endogenous genomic loci and visualized them upon pairing of receiver (Notch) and sender (Delta) cells as a function of time after cell contact. At contact sites, Notch and Delta immediately accumulated at 1:1 stoichiometry in synapses, which resolved by 15-20 min after contact. Synapse formation preceded the entrance of the Notch extracellular domain into the sender cell and accumulation of NICD in the nucleus of the receiver cell, which approached a maximum after ∼45 min and was prevented by chemical and genetic inhibitors of signaling. These findings directly link Notch-Delta synapse dynamics to NICD production with spatiotemporal precision.
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Affiliation(s)
- Lena Tveriakhina
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Gustavo Scanavachi
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA; Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA
| | - Emily D Egan
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Ricardo Bango Da Cunha Correia
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA; Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA
| | - Alexandre P Martin
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Julia M Rogers
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Jeremy S Yodh
- Department of Physics, Harvard University, Cambridge, MA 02138, USA
| | - Jon C Aster
- Department of Pathology, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Tom Kirchhausen
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA; Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA.
| | - Stephen C Blacklow
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA; Department of Cancer Biology, Dana Farber Cancer Institute, Boston, MA 02215, USA.
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3
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Tveriakhina L, Scanavachi G, Egan ED, Correia RBDC, Martin AP, Rogers JM, Yodh JS, Aster JC, Kirchhausen T, Blacklow SC. Temporal Dynamics and Stoichiometry in Notch Signaling - from Notch Synaptic Complex Formation to NICD Nuclear Entry. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.27.559780. [PMID: 37808809 PMCID: PMC10557745 DOI: 10.1101/2023.09.27.559780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
Mammalian Notch signaling occurs when binding of Delta or Jagged to Notch stimulates proteolytic release of the Notch intracellular domain (NICD), which enters the nucleus to regulate target gene expression. To determine the temporal dynamics of events associated with Notch signaling under native conditions, we fluorescently tagged Notch and Delta at their endogenous genomic loci and visualized them upon pairing of receiver (Notch) and sender (Delta) cells as a function of time after cell contact. At contact sites, Notch and Delta immediately accumulated at 1:1 stoichiometry in synapses, which resolved by 15-20 min after contact. Synapse formation preceded entrance of the Notch extracellular domain into the sender cell and accumulation of NICD in the nucleus of the receiver cell, which approached a maximum after ∼45 min and was prevented by chemical and genetic inhibitors of signaling. These findings directly link Notch-Delta synapse dynamics to NICD production with unprecedented spatiotemporal precision.
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4
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Rosales-Vega M, Reséndez-Pérez D, Zurita M, Vázquez M. TnaA, a trithorax group protein, modulates wingless expression in different regions of the Drosophila wing imaginal disc. Sci Rep 2023; 13:15162. [PMID: 37704704 PMCID: PMC10499800 DOI: 10.1038/s41598-023-42169-z] [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: 02/09/2023] [Accepted: 09/06/2023] [Indexed: 09/15/2023] Open
Abstract
wingless expression is exquisitely regulated by different factors and enhancers in the imaginal wing discs of Drosophila melanogaster in four domains: the dorsal band, the dorso-ventral boundary, and the inner and outer ring domains. tonalli is a trithorax group gene that encodes a putative SUMO E3 ligase that binds to chromatin to regulate the expression of its targets, including the Hox genes. However, its role in modulating gene expression is barely known. Here, we show that TnaA modulates the wingless expression at two domains of the wing disc, the dorso-ventral boundary and the inner ring. At first, tonalli interacts genetically with Notch to form the wing margin. In the inner ring domain, TnaA modulates wingless transcription. When the dosage of TnaA increases in or near the inner ring since early larval stages, this domain expands with a rapid increase in wingless expression. TnaA occupies the wingless Inner Ring Enhancer at the wing disc, meanwhile it does not affect wingless expression directed by the Ventral Disc Enhancer in leg discs, suggesting that TnaA acts as a wingless enhancer-specific factor. We describe for the first time the presence of TnaA at the Inner Ring Enhancer as a specific regulator of wingless in the development of wing boundaries.
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Affiliation(s)
- Marco Rosales-Vega
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, 62210, Cuernavaca, Morelos, Mexico
| | - Diana Reséndez-Pérez
- Departamento de Inmunología y Virología, Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, Nuevo León, Mexico
| | - Mario Zurita
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, 62210, Cuernavaca, Morelos, Mexico
| | - Martha Vázquez
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, 62210, Cuernavaca, Morelos, Mexico.
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5
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Ruiz-Otero N, Kuruvilla R. Role of Delta/Notch-like EGF-related receptor in blood glucose homeostasis. Front Endocrinol (Lausanne) 2023; 14:1161085. [PMID: 37223028 PMCID: PMC10200888 DOI: 10.3389/fendo.2023.1161085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 04/18/2023] [Indexed: 05/25/2023] Open
Abstract
Cell-cell interactions are necessary for optimal endocrine functions in the pancreas. β-cells, characterized by the expression and secretion of the hormone insulin, are a major constituent of functional micro-organs in the pancreas known as islets of Langerhans. Cell-cell contacts between β-cells are required to regulate insulin production and glucose-stimulated insulin secretion, which are key determinants of blood glucose homeostasis. Contact-dependent interactions between β-cells are mediated by gap junctions and cell adhesion molecules such as E-cadherin and N-CAM. Recent genome-wide studies have implicated Delta/Notch-like EGF-related receptor (Dner) as a potential susceptibility locus for Type 2 Diabetes in humans. DNER is a transmembrane protein and a proposed Notch ligand. DNER has been implicated in neuron-glia development and cell-cell interactions. Studies herein demonstrate that DNER is expressed in β-cells with an onset during early postnatal life and sustained throughout adulthood in mice. DNER loss in adult β-cells in mice (β-Dner cKO mice) disrupted islet architecture and decreased the expression of N-CAM and E-cadherin. β-Dner cKO mice also exhibited impaired glucose tolerance, defects in glucose- and KCl-induced insulin secretion, and decreased insulin sensitivity. Together, these studies suggest that DNER plays a crucial role in mediating islet cell-cell interactions and glucose homeostasis.
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Affiliation(s)
- Nelmari Ruiz-Otero
- Division of Endocrinology, Diabetes & Metabolism, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Rejji Kuruvilla
- Department of Biology, Johns Hopkins University, Baltimore, MD, United States
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Carter AA, Ramsey KM, Hatem CL, Sherry KP, Majumdar A, Barrick D. Structural features of the Notch ankyrin domain-Deltex WWE 2 domain heterodimer determined by NMR spectroscopy and functional implications. Structure 2023; 31:584-594.e5. [PMID: 36977409 PMCID: PMC10338078 DOI: 10.1016/j.str.2023.03.003] [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: 02/21/2020] [Revised: 11/14/2022] [Accepted: 03/02/2023] [Indexed: 03/29/2023]
Abstract
The Notch signaling pathway, an important cell fate determination pathway, is modulated by the ubiquitin ligase Deltex. Here, we investigate the structural basis for Deltex-Notch interaction. We used nuclear magnetic resonance (NMR) spectroscopy to assign the backbone of the Drosophila Deltex WWE2 domain and mapped the binding site of the Notch ankyrin (ANK) domain to the N-terminal WWEA motif. Using cultured Drosophila S2R+ cells, we find that point substitutions within the ANK-binding surface of Deltex disrupt Deltex-mediated enhancement of Notch transcriptional activation and disrupt ANK binding in cells and in vitro. Likewise, ANK substitutions that disrupt Notch-Deltex heterodimer formation in vitro block disrupt Deltex-mediated stimulation of Notch transcription activation and diminish interaction with full-length Deltex in cells. Surprisingly, the Deltex-Notch intracellular domain (NICD) interaction is not disrupted by deletion of the Deltex WWE2 domain, suggesting a secondary Notch-Deltex interaction. These results show the importance of the WWEA:ANK interaction in enhancing Notch signaling.
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Affiliation(s)
- Andrea A Carter
- T.C. Jenkins Department of Biophysics, Johns Hopkins University, 3400 N. Charles St., Baltimore, MD 21218, USA
| | - Kristen M Ramsey
- T.C. Jenkins Department of Biophysics, Johns Hopkins University, 3400 N. Charles St., Baltimore, MD 21218, USA
| | - Christine L Hatem
- T.C. Jenkins Department of Biophysics, Johns Hopkins University, 3400 N. Charles St., Baltimore, MD 21218, USA
| | - Kathryn P Sherry
- T.C. Jenkins Department of Biophysics, Johns Hopkins University, 3400 N. Charles St., Baltimore, MD 21218, USA
| | - Ananya Majumdar
- Biomolecular NMR Center, Johns Hopkins University, 3400 N. Charles St., Baltimore, MD 21218, USA
| | - Doug Barrick
- T.C. Jenkins Department of Biophysics, Johns Hopkins University, 3400 N. Charles St., Baltimore, MD 21218, USA.
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Beenken A, Cerutti G, Brasch J, Guo Y, Sheng Z, Erdjument-Bromage H, Aziz Z, Robbins-Juarez SY, Chavez EY, Ahlsen G, Katsamba PS, Neubert TA, Fitzpatrick AWP, Barasch J, Shapiro L. Structures of LRP2 reveal a molecular machine for endocytosis. Cell 2023; 186:821-836.e13. [PMID: 36750096 PMCID: PMC9993842 DOI: 10.1016/j.cell.2023.01.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 11/29/2022] [Accepted: 01/10/2023] [Indexed: 02/08/2023]
Abstract
The low-density lipoprotein (LDL) receptor-related protein 2 (LRP2 or megalin) is representative of the phylogenetically conserved subfamily of giant LDL receptor-related proteins, which function in endocytosis and are implicated in diseases of the kidney and brain. Here, we report high-resolution cryoelectron microscopy structures of LRP2 isolated from mouse kidney, at extracellular and endosomal pH. The structures reveal LRP2 to be a molecular machine that adopts a conformation for ligand binding at the cell surface and for ligand shedding in the endosome. LRP2 forms a homodimer, the conformational transformation of which is governed by pH-sensitive sites at both homodimer and intra-protomer interfaces. A subset of LRP2 deleterious missense variants in humans appears to impair homodimer assembly. These observations lay the foundation for further understanding the function and mechanism of LDL receptors and implicate homodimerization as a conserved feature of the LRP receptor subfamily.
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Affiliation(s)
- Andrew Beenken
- Division of Nephrology, Department of Medicine, Columbia University Vagelos College of Physicians and Surgeons, New York, NY 10032, USA
| | - Gabriele Cerutti
- Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY 10027, USA
| | - Julia Brasch
- Department of Biochemistry, University of Utah, Salt Lake City, UT 84112, USA
| | - Yicheng Guo
- Aaron Diamond AIDS Research Center, Columbia University, New York, NY 10032, USA
| | - Zizhang Sheng
- Aaron Diamond AIDS Research Center, Columbia University, New York, NY 10032, USA
| | - Hediye Erdjument-Bromage
- Department of Cell Biology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Zainab Aziz
- Vagelos College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
| | | | - Estefania Y Chavez
- Department of Pediatrics, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA
| | - Goran Ahlsen
- Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY 10027, USA
| | - Phinikoula S Katsamba
- Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY 10027, USA
| | - Thomas A Neubert
- Department of Cell Biology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Anthony W P Fitzpatrick
- Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY 10027, USA; Department of Biochemistry and Molecular Biophysics, Columbia University Vagelos College of Physicians and Surgeons, New York, NY 10032, USA; Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Irving Medical Center, New York, NY 10032, USA.
| | - Jonathan Barasch
- Division of Nephrology, Department of Medicine, Columbia University Vagelos College of Physicians and Surgeons, New York, NY 10032, USA; Department of Pathology and Cell Biology, Columbia University Vagelos College of Physicians and Surgeons, New York, NY 10032, USA; Columbia University George M. O'Brien Urology Center, New York, NY 10032, USA.
| | - Lawrence Shapiro
- Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY 10027, USA; Aaron Diamond AIDS Research Center, Columbia University, New York, NY 10032, USA; Department of Biochemistry and Molecular Biophysics, Columbia University Vagelos College of Physicians and Surgeons, New York, NY 10032, USA.
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8
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Notch Missense Mutations in Drosophila Reveal Functions of Specific EGF-like Repeats in Notch Folding, Trafficking, and Signaling. Biomolecules 2022; 12:biom12121752. [PMID: 36551180 PMCID: PMC9775759 DOI: 10.3390/biom12121752] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Revised: 10/10/2022] [Accepted: 10/14/2022] [Indexed: 11/29/2022] Open
Abstract
Notch signaling plays various roles in cell-fate specification through direct cell-cell interactions. Notch receptors are evolutionarily conserved transmembrane proteins with multiple epidermal growth factor (EGF)-like repeats. Drosophila Notch has 36 EGF-like repeats, and while some play a role in Notch signaling, the specific functions of most remain unclear. To investigate the role of each EGF-like repeat, we used 19 previously identified missense mutations of Notch with unique amino acid substitutions in various EGF-like repeats and a transmembrane domain; 17 of these were identified through a single genetic screen. We assessed these mutants' phenotypes in the nervous system and hindgut during embryogenesis, and found that 10 of the 19 Notch mutants had defects in both lateral inhibition and inductive Notch signaling, showing context dependency. Of these 10 mutants, six accumulated Notch in the endoplasmic reticulum (ER), and these six were located in EGF-like repeats 8-10 or 25. Mutations with cysteine substitutions were not always coupled with ER accumulation. This suggests that certain EGF-like repeats may be particularly susceptible to structural perturbation, resulting in a misfolded and inactive Notch product that accumulates in the ER. Thus, we propose that these EGF-like repeats may be integral to Notch folding.
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Ravel JM, Comel M, Wandzel M, Bronner M, Tatopoulos A, Renaud M, Lambert L, Bursztejn AC, Bonnet C. First report of a short in-frame biallelic deletion removing part of the EGF-like domain calcium-binding motif in LTBP4 and causing autosomal recessive cutis laxa type 1C. Am J Med Genet A 2022; 188:3343-3349. [PMID: 35972031 DOI: 10.1002/ajmg.a.62954] [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: 03/21/2022] [Revised: 07/01/2022] [Accepted: 08/01/2022] [Indexed: 01/31/2023]
Abstract
Cutis laxa (CL) is a rare connective tissue disorder characterized by wrinkled, abundant and sagging skin, sometimes associated with systemic impairment. Biallelic alterations in latent transforming growth factor beta-binding protein 4 gene (LTBP4) cause autosomal recessive type 1C cutis laxa (ARCL1C, MIM #613177). The present report describes the case of a 17-months-old girl with cutis laxa together with a literature review of previous ARCL1C cases. Based on proband main clinical signs (cutis laxa and pulmonary emphysema), clinical exome sequencing (CES) was performed and showed a new nine base-pairs homozygous in-frame deletion in LTBP4 gene. RT-PCR and cDNA Sanger sequencing were performed in order to clarify its impact on RNA. This report demonstrates that a genetic alteration in the EGF-like 14 domain calcium-binding motif of LTBP4 gene is likely responsible for cutis laxa in our patient.
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Affiliation(s)
- Jean-Marie Ravel
- Laboratoire de génétique médicale, CHRU Nancy, Nancy, France.,Université de Lorraine, INSERM UMR_S1256, NGERE, Nancy, France
| | - Margot Comel
- Laboratoire de génétique médicale, CHRU Nancy, Nancy, France
| | - Marion Wandzel
- Laboratoire de génétique médicale, CHRU Nancy, Nancy, France
| | - Myriam Bronner
- Laboratoire de génétique médicale, CHRU Nancy, Nancy, France
| | | | - Mathilde Renaud
- Université de Lorraine, INSERM UMR_S1256, NGERE, Nancy, France.,Service de génétique médicale, CHRU de Nancy, Nancy, France
| | - Laëtitia Lambert
- Université de Lorraine, INSERM UMR_S1256, NGERE, Nancy, France.,Service de génétique médicale, CHRU de Nancy, Nancy, France
| | | | - Céline Bonnet
- Laboratoire de génétique médicale, CHRU Nancy, Nancy, France.,Université de Lorraine, INSERM UMR_S1256, NGERE, Nancy, France
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10
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Mugisha S, Di X, Disoma C, Jiang H, Zhang S. Fringe family genes and their modulation of Notch signaling in cancer. Biochim Biophys Acta Rev Cancer 2022; 1877:188746. [PMID: 35660646 DOI: 10.1016/j.bbcan.2022.188746] [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: 02/05/2022] [Revised: 05/30/2022] [Accepted: 05/30/2022] [Indexed: 11/26/2022]
Abstract
Fringes are glycosyltransferases that transfer N-acetylglucosamine to the O-linked fucose of Notch receptors. They regulate the Notch signaling activity that drives tumor formation and progression, resulting in poor prognosis. However, the specific tumor-promoting role of Fringes differs depending on the type of cancer. Although a particular Fringe member could act as a tumor suppressor in one cancer type, it may act as an oncogene in another. This review discusses the tumorigenic role of the Fringe family (lunatic fringe, manic fringe, and radical fringe) in modulating Notch signaling in various cancers. Although the crucial functions of Fringes continue to emerge as more mechanistic studies are being pursued, further translational research is needed to explore their roles and therapeutic benefits in various malignancies.
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Affiliation(s)
- Samson Mugisha
- Department of Cell Biology, School of Life Sciences, Central South University, Changsha, Hunan 410013, PR China
| | - Xiaotang Di
- Department of Cell Biology, School of Life Sciences, Central South University, Changsha, Hunan 410013, PR China
| | - Cyrollah Disoma
- Department of Cell Biology, School of Life Sciences, Central South University, Changsha, Hunan 410013, PR China
| | - Hao Jiang
- Department of Biomedical Informatics, School of Life Sciences, Central South University, Changsha, Hunan 410013, PR China.
| | - Shubing Zhang
- Department of Cell Biology, School of Life Sciences, Central South University, Changsha, Hunan 410013, PR China; Hunan Key Laboratory of Animal Models for Human Diseases, Central South University, Changsha, Hunan 410013, PR China.
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11
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Bajpai S, Chelakkot R, Prabhakar R, Inamdar MM. Role of Delta-Notch signalling molecules on cell-cell adhesion in determining heterogeneous chemical and cell morphological patterning. SOFT MATTER 2022; 18:3505-3520. [PMID: 35438097 DOI: 10.1039/d2sm00064d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Cell mechanics and motility are responsible for collective motion of cells that result in overall deformation of epithelial tissues. On the other hand, contact-dependent cell-cell signalling is responsible for generating a large variety of intricate, self-organized, spatial patterns of the signalling molecules. Moreover, it is becoming increasingly clear that the combined mechanochemical patterns of cell shape/size and signalling molecules in the tissues, for example, in cancerous and sensory epithelium, are governed by mechanochemical coupling between chemical signalling and cell mechanics. However, a clear quantitative picture of how these two aspects of tissue dynamics, i.e., signalling and mechanics, lead to pattern and form is still emerging. Although, a number of recent experiments demonstrate that cell mechanics, cell motility, and cell-cell signalling are tightly coupled in many morphogenetic processes, relatively few modeling efforts have focused on an integrated approach. We extend the vertex model of an epithelial monolayer to account for contact-dependent signalling between adjacent cells and between non-adjacent neighbors through long protrusional contacts with a feedback mechanism wherein the adhesive strength between adjacent cells is controlled by the expression of the signalling molecules in those cells. Local changes in cell-cell adhesion lead to changes in cell shape and size, which in turn drives changes in the levels of signalling molecules. Our simulations show that even this elementary two-way coupling of chemical signalling and cell mechanics is capable of giving rise to a rich variety of mechanochemical patterns in epithelial tissues. In particular, under certain parametric conditions, bimodal distributions in cell size and shape are obtained, which resemble experimental observations in cancerous and sensory tissues.
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Affiliation(s)
- Supriya Bajpai
- IITB-Monash Research Academy, Mumbai 400076, India.
- Department of Mechanical and Aerospace Engineering, Monash University, Clayton, VIC 3800, Australia.
- Department of Civil Engineering, Indian Institute of Technology Bombay, Mumbai 400076, India.
| | - Raghunath Chelakkot
- Department of Physics, Indian Institute of Technology Bombay, Mumbai 400076, India.
| | - Ranganathan Prabhakar
- Department of Mechanical and Aerospace Engineering, Monash University, Clayton, VIC 3800, Australia.
| | - Mandar M Inamdar
- Department of Civil Engineering, Indian Institute of Technology Bombay, Mumbai 400076, India.
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12
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Schnute B, Shimizu H, Lyga M, Baron M, Klein T. Ubiquitylation is required for the incorporation of the Notch receptor into intraluminal vesicles to prevent prolonged and ligand-independent activation of the pathway. BMC Biol 2022; 20:65. [PMID: 35264151 PMCID: PMC8908686 DOI: 10.1186/s12915-022-01245-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Accepted: 02/01/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Ubiquitylation of the ligands and the receptor plays an important part in the regulation of the activity of the evolutionary conserved Notch signalling pathway. However, its function for activation of Notch is not completely understood, despite the identification of several E3 ligases devoted to the receptor. RESULTS Here we analysed a variant of the Notch receptor where all lysines in its intracellular domain are replaced by arginines. Our analysis of this variant revealed that ubiquitylation of Notch is not essential for its endocytosis. We identified two functions for ubiquitylation of lysines in the Notch receptor. First, it is required for the degradation of free Notch intracellular domain (NICD) in the nucleus, which prevents a prolonged activation of the pathway. More importantly, it is also required for the incorporation of Notch into intraluminal vesicles of maturing endosomes to prevent ligand-independent activation of the pathway from late endosomal compartments. CONCLUSIONS The findings clarify the role of lysine-dependent ubiquitylation of the Notch receptor and indicate that Notch is endocytosed by several independent operating mechanisms.
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Affiliation(s)
- Björn Schnute
- Institute of Genetics, Heinrich-Heine-University Duesseldorf, Universitaetsstr. 1, 40225, Duesseldorf, Germany
| | - Hideyuki Shimizu
- School of Biological Sciences, University of Manchester, Michael Smith Building, Oxford Road, Manchester, M13 9PT, UK
| | - Marvin Lyga
- Institute of Genetics, Heinrich-Heine-University Duesseldorf, Universitaetsstr. 1, 40225, Duesseldorf, Germany
| | - Martin Baron
- School of Biological Sciences, University of Manchester, Michael Smith Building, Oxford Road, Manchester, M13 9PT, UK
| | - Thomas Klein
- Institute of Genetics, Heinrich-Heine-University Duesseldorf, Universitaetsstr. 1, 40225, Duesseldorf, Germany.
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Salazar JL, Yang SA, Lin YQ, Li-Kroeger D, Marcogliese PC, Deal SL, Neely GG, Yamamoto S. TM2D genes regulate Notch signaling and neuronal function in Drosophila. PLoS Genet 2021; 17:e1009962. [PMID: 34905536 PMCID: PMC8714088 DOI: 10.1371/journal.pgen.1009962] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 12/28/2021] [Accepted: 11/23/2021] [Indexed: 12/26/2022] Open
Abstract
TM2 domain containing (TM2D) proteins are conserved in metazoans and encoded by three separate genes in each model organism species that has been sequenced. Rare variants in TM2D3 are associated with Alzheimer's disease (AD) and its fly ortholog almondex is required for embryonic Notch signaling. However, the functions of this gene family remain elusive. We knocked-out all three TM2D genes (almondex, CG11103/amaretto, CG10795/biscotti) in Drosophila and found that they share the same maternal-effect neurogenic defect. Triple null animals are not phenotypically worse than single nulls, suggesting these genes function together. Overexpression of the most conserved region of the TM2D proteins acts as a potent inhibitor of Notch signaling at the γ-secretase cleavage step. Lastly, Almondex is detected in the brain and its loss causes shortened lifespan accompanied by progressive motor and electrophysiological defects. The functional links between all three TM2D genes are likely to be evolutionarily conserved, suggesting that this entire gene family may be involved in AD.
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Affiliation(s)
- Jose L. Salazar
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, Texas, United States of America
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, Texas, United States of America
| | - Sheng-An Yang
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, Texas, United States of America
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, Texas, United States of America
| | - Yong Qi Lin
- The Dr. John and Anne Chong Lab for Functional Genomics, Charles Perkins Centre and School of Life and Environmental Sciences, The University of Sydney, Sydney, Australia
| | - David Li-Kroeger
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, Texas, United States of America
- Department of Neurology, BCM, Houston, Texas, United States of America
- Center for Alzheimer’s and Neurodegenerative Diseases, BCM, Houston, Texas, United States of America
| | - Paul C. Marcogliese
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, Texas, United States of America
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, Texas, United States of America
| | - Samantha L. Deal
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, Texas, United States of America
- Program in Developmental Biology, BCM, Houston, Texas, United States of America
| | - G. Gregory Neely
- The Dr. John and Anne Chong Lab for Functional Genomics, Charles Perkins Centre and School of Life and Environmental Sciences, The University of Sydney, Sydney, Australia
| | - Shinya Yamamoto
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, Texas, United States of America
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, Texas, United States of America
- Center for Alzheimer’s and Neurodegenerative Diseases, BCM, Houston, Texas, United States of America
- Program in Developmental Biology, BCM, Houston, Texas, United States of America
- Development, Disease Models & Therapeutics Graduate Program, BCM, Houston, Texas, United States of America
- Department of Neuroscience, BCM, Houston, Texas, United States of America
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14
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Nagel AC, Müller D, Zimmermann M, Preiss A. The Membrane-Bound Notch Regulator Mnr Supports Notch Cleavage and Signaling Activity in Drosophila melanogaster. Biomolecules 2021; 11:1672. [PMID: 34827670 PMCID: PMC8615698 DOI: 10.3390/biom11111672] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 10/28/2021] [Accepted: 11/04/2021] [Indexed: 11/17/2022] Open
Abstract
The Notch signaling pathway is pivotal to cellular differentiation. Activation of this pathway involves proteolysis of the Notch receptor and the release of the biologically active Notch intracellular domain, acting as a transcriptional co-activator of Notch target genes. While the regulation of Notch signaling dynamics at the level of ligand-receptor interaction, endocytosis, and transcriptional regulation has been well studied, little is known about factors influencing Notch cleavage. We identified EP555 as a suppressor of the Notch antagonist Hairless (H). EP555 drives expression of CG32521 encoding membrane-bound proteins, which we accordingly rename membrane-bound Notch regulator (mnr). Within the signal-receiving cell, upregulation of Mnr stimulates Notch receptor activation, whereas a knockdown reduces it, without apparent influence on ligand-receptor interaction. We provide evidence that Mnr plays a role in γ-secretase-mediated intramembrane cleavage of the Notch receptor. As revealed by a fly-eye-based reporter system, γ-secretase activity is stimulated by the overexpression of Mnr, and is inhibited by its knockdown. We conclude that Mnr proteins support Notch signaling activity by fostering the cleavage of the Notch receptor. With Mnr, we identified a membrane-bound factor directly augmenting Notch intra-membrane processing, thereby acting as a positive regulator of Notch signaling activity.
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Affiliation(s)
- Anja C. Nagel
- Department of General Genetics 190g, University of Hohenheim, Garbenstr. 30, 70599 Stuttgart, Germany; (D.M.); (M.Z.); (A.P.)
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15
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Pinte S, Delfortrie S, Havet C, Villain G, Mattot V, Soncin F. EGF repeats of epidermal growth factor‑like domain 7 promote endothelial cell activation and tumor escape from the immune system. Oncol Rep 2021; 47:8. [PMID: 34738625 DOI: 10.3892/or.2021.8219] [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: 03/15/2021] [Accepted: 08/23/2021] [Indexed: 11/06/2022] Open
Abstract
The tumor blood vessel endothelium forms a barrier that must be crossed by circulating immune cells in order for them to reach and kill cancer cells. Epidermal growth factor‑like domain 7 (Egfl7) represses this immune infiltration by lowering the expression levels of leukocyte adhesion receptors on the surface of endothelial cells. However, the protein domains involved in these properties are not completely understood. Egfl7 is structurally composed of the predicted EMI‑, EGF‑ and C‑terminal domains. The present study aimed to investigate the roles of these different domains in tumor development by designing retroviruses coding for deletion mutants and then infecting 4T1 breast cancer cell populations, which consequently overexpressed the variants. By performing in vitro soft‑agar assays, it was found that Egfl7 and its deletion variants did not affect cell proliferation or anchorage‑independent growth. When 4T1 cells expressing either the wild‑type Egfl7 protein or Egfl7 domain variants were implanted in mice, Egfl7 expression markedly promoted tumor development and deletion of the EGF repeats decreased the tumor growth rate. By contrast, deleting any other domain displayed no significant effect on tumor development. The overexpression of Egfl7 also decreased T cell and natural killer cell infiltration in tumors, as determined by immunofluorescence staining of tumor sections, whereas deletion of the EGF repeats inhibited this effect. Reverse transcription‑quantitative PCR analysis of the mechanisms involved revealed that deleting the EGF repeats partially restored the expression levels of vascular cell adhesion molecule 1 and E‑selectin, which were suppressed by overexpression of Egfl7 in endothelial cells in vitro. This resulted in a higher number of lymphocytes bound to HUVEC expressing Egfl7‑ΔEGF compared with HUVEC expressing wild‑type Egfl7, as assessed by fluorescent‑THP‑1 adhesion assays onto endothelial cells. Overall, the present study demonstrated that the EGF repeats may participate in the protumoral and anti‑inflammatory effects of Egfl7.
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Affiliation(s)
- Sébastien Pinte
- Université de Lille, CNRS, Institut Pasteur de Lille, UMR 8161‑M3T‑Mechanisms of Tumorigenesis and Target Therapies, 59000 Lille, France
| | - Suzanne Delfortrie
- Université de Lille, CNRS, Institut Pasteur de Lille, UMR 8161‑M3T‑Mechanisms of Tumorigenesis and Target Therapies, 59000 Lille, France
| | - Chantal Havet
- Université de Lille, CNRS, Institut Pasteur de Lille, UMR 8161‑M3T‑Mechanisms of Tumorigenesis and Target Therapies, 59000 Lille, France
| | - Gaëlle Villain
- Université de Lille, CNRS, Institut Pasteur de Lille, UMR 8161‑M3T‑Mechanisms of Tumorigenesis and Target Therapies, 59000 Lille, France
| | - Virginie Mattot
- Université de Lille, CNRS, Institut Pasteur de Lille, UMR 8161‑M3T‑Mechanisms of Tumorigenesis and Target Therapies, 59000 Lille, France
| | - Fabrice Soncin
- Université de Lille, CNRS, Institut Pasteur de Lille, UMR 8161‑M3T‑Mechanisms of Tumorigenesis and Target Therapies, 59000 Lille, France
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16
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Martinez Lyons A, Boulter L. The developmental origins of Notch-driven intrahepatic bile duct disorders. Dis Model Mech 2021; 14:dmm048413. [PMID: 34549776 PMCID: PMC8480193 DOI: 10.1242/dmm.048413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The Notch signaling pathway is an evolutionarily conserved mechanism of cell-cell communication that mediates cellular proliferation, cell fate specification, and maintenance of stem and progenitor cell populations. In the vertebrate liver, an absence of Notch signaling results in failure to form bile ducts, a complex tubular network that radiates throughout the liver, which, in healthy individuals, transports bile from the liver into the bowel. Loss of a functional biliary network through congenital malformations during development results in cholestasis and necessitates liver transplantation. Here, we examine to what extent Notch signaling is necessary throughout embryonic life to initiate the proliferation and specification of biliary cells and concentrate on the animal and human models that have been used to define how perturbations in this signaling pathway result in developmental liver disorders.
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Affiliation(s)
| | - Luke Boulter
- MRC Human Genetics Unit, Institute of Genetics and Cancer, Edinburgh EH4 2XU, UK
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17
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Albakri M, Tashkandi H, Zhou L. A Review of Advances in Hematopoietic Stem Cell Mobilization and the Potential Role of Notch2 Blockade. Cell Transplant 2021; 29:963689720947146. [PMID: 32749152 PMCID: PMC7563033 DOI: 10.1177/0963689720947146] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Hematopoietic stem cell (HSC) transplantation can be a potential cure for
hematological malignancies and some nonhematologic diseases. Hematopoietic stem
and progenitor cells (HSPCs) collected from peripheral blood after mobilization
are the primary source to provide HSC transplantation. In most of the cases,
mobilization by the cytokine granulocyte colony-stimulating factor with
chemotherapy, and in some settings, with the CXC chemokine receptor type 4
antagonist plerixafor, can achieve high yield of hematopoietic progenitor cells
(HPCs). However, adequate mobilization is not always successful in a significant
portion of donors. Research is going on to find new agents or strategies to
increase HSC mobilization. Here, we briefly review the history of HSC
transplantation, current mobilization regimens, some of the novel agents that
are under investigation for clinical practice, and our recent findings from
animal studies regarding Notch and ligand interaction as potential targets for
HSPC mobilization.
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Affiliation(s)
- Marwah Albakri
- Department of Pathology, Case Western Reserve University, Cleveland, OH, USA
| | - Hammad Tashkandi
- Department of Pathology, University of Pittsburgh Medical Center, PA, USA
| | - Lan Zhou
- Department of Pathology, Case Western Reserve University, Cleveland, OH, USA
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18
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Yu S, Wang W, Albakri M, Yu X, Majihail G, Lim S, Lopilato RK, Ito A, Letterio J, Haltiwanger RS, Zhou L. O-Fucose and Fringe-modified NOTCH1 extracellular domain fragments as decoys to release niche-lodged hematopoietic progenitor cells. Glycobiology 2021; 31:582-592. [PMID: 33351914 PMCID: PMC8176772 DOI: 10.1093/glycob/cwaa113] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 11/14/2020] [Accepted: 12/07/2020] [Indexed: 12/25/2022] Open
Abstract
Successful hematopoietic progenitor cell (HPC) transplant therapy is improved by mobilizing HPCs from the bone marrow niche in donors. Notch receptor-ligand interactions are known to retain HPCs in the bone marrow, and neutralizing antibodies against Notch ligands, Jagged-1 or Delta-like ligand (DLL4), or NOTCH2 receptor potentiates HPC mobilization. Notch-ligand interactions are dependent on posttranslational modification of Notch receptors with O-fucose and are modulated by Fringe-mediated extension of O-fucose moieties. We previously reported that O-fucosylglycans on Notch are required for Notch receptor-ligand engagement controlling hematopoietic stem cell quiescence and retention in the marrow niche. Here, we generated recombinant fragments of NOTCH1 or NOTCH2 extracellular domain carrying the core ligand-binding regions (EGF11-13) either as unmodified forms or as O-fucosylglycan-modified forms. We found that the addition of O-fucose monosaccharide or the Fringe-extended forms of O-fucose to EGF11-13 showed substantial increases in binding to DLL4. Furthermore, the O-fucose and Fringe-extended NOTCH1 EGF11-13 protein displayed much stronger binding to DLL4 than the NOTCH2 counterpart. When assessed in an in vitro 3D osteoblastic niche model, we showed that the Fringe-extended NOTCH1 EGF11-13 fragment effectively released lodged HPC cells with a higher potency than the NOTCH2 blocking antibody. We concluded that O-fucose and Fringe-modified NOTCH1 EGF11-13 protein can be utilized as effective decoys for stem cell niche localized ligands to potentiate HPC egress and improve HPC collection for hematopoietic cell therapy.
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Affiliation(s)
- Shuiliang Yu
- Department of Pathology, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Weihuan Wang
- Department of Pathology, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Marwah Albakri
- Department of Pathology, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Xiaoxing Yu
- Beachwood High School, Beachwood, OH 44122, USA
| | | | - Seunghwan Lim
- Department of Pediatrics, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Rachel K Lopilato
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA
| | - Atsuko Ito
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA
| | - John Letterio
- Department of Pediatrics, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Robert S Haltiwanger
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA
| | - Lan Zhou
- Department of Pathology, Case Western Reserve University, Cleveland, OH 44106, USA
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19
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Abstract
Notch signaling is a conserved system of communication between adjacent cells, influencing numerous cell fate decisions in the development of multicellular organisms. Aberrant signaling is also implicated in many human pathologies. At its core, Notch has a mechanotransduction module that decodes receptor-ligand engagement at the cell surface under force to permit proteolytic cleavage of the receptor, leading to the release of the Notch intracellular domain (NICD). NICD enters the nucleus and acts as a transcriptional effector to regulate expression of Notch-responsive genes. In this article, we review and integrate current understanding of the detailed molecular basis for Notch signal transduction, highlighting quantitative, structural, and dynamic features of this developmentally central signaling mechanism. We discuss the implications of this mechanistic understanding for the functionality of the signaling pathway in different molecular and cellular contexts.
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Affiliation(s)
- David Sprinzak
- George S. Wise Faculty of Life Sciences, School of Neurobiology, Biochemistry, and Biophysics, Tel Aviv University, Tel Aviv 69978, Israel;
| | - Stephen C Blacklow
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, Massachusetts 02115, USA;
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20
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Christopoulos PF, Gjølberg TT, Krüger S, Haraldsen G, Andersen JT, Sundlisæter E. Targeting the Notch Signaling Pathway in Chronic Inflammatory Diseases. Front Immunol 2021; 12:668207. [PMID: 33912195 PMCID: PMC8071949 DOI: 10.3389/fimmu.2021.668207] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 03/24/2021] [Indexed: 12/14/2022] Open
Abstract
The Notch signaling pathway regulates developmental cell-fate decisions and has recently also been linked to inflammatory diseases. Although therapies targeting Notch signaling in inflammation in theory are attractive, their design and implementation have proven difficult, at least partly due to the broad involvement of Notch signaling in regenerative and homeostatic processes. In this review, we summarize the supporting role of Notch signaling in various inflammation-driven diseases, and highlight efforts to intervene with this pathway by targeting Notch ligands and/or receptors with distinct therapeutic strategies, including antibody designs. We discuss this in light of lessons learned from Notch targeting in cancer treatment. Finally, we elaborate on the impact of individual Notch members in inflammation, which may lay the foundation for development of therapeutic strategies in chronic inflammatory diseases.
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Affiliation(s)
| | - Torleif T. Gjølberg
- Institute of Clinical Medicine and Department of Pharmacology, University of Oslo and Oslo University Hospital, Oslo, Norway
- Centre for Eye Research and Department of Ophthalmology, University of Oslo and Oslo University Hospital, Oslo, Norway
- Department of Immunology, University of Oslo and Oslo University Hospital, Oslo, Norway
| | - Stig Krüger
- Department of Pathology, University of Oslo and Oslo University Hospital, Oslo, Norway
| | - Guttorm Haraldsen
- Department of Pathology, University of Oslo and Oslo University Hospital, Oslo, Norway
| | - Jan Terje Andersen
- Institute of Clinical Medicine and Department of Pharmacology, University of Oslo and Oslo University Hospital, Oslo, Norway
- Department of Immunology, University of Oslo and Oslo University Hospital, Oslo, Norway
| | - Eirik Sundlisæter
- Department of Pathology, University of Oslo and Oslo University Hospital, Oslo, Norway
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21
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Intracellular trafficking of Notch orchestrates temporal dynamics of Notch activity in the fly brain. Nat Commun 2021; 12:2083. [PMID: 33828096 PMCID: PMC8027629 DOI: 10.1038/s41467-021-22442-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 03/16/2021] [Indexed: 12/03/2022] Open
Abstract
While Delta non-autonomously activates Notch in neighboring cells, it autonomously inactivates Notch through cis-inhibition, the molecular mechanism and biological roles of which remain elusive. The wave of differentiation in the Drosophila brain, the ‘proneural wave’, is an excellent model for studying Notch signaling in vivo. Here, we show that strong nonlinearity in cis-inhibition reproduces the second peak of Notch activity behind the proneural wave in silico. Based on this, we demonstrate that Delta expression induces a quick degradation of Notch in late endosomes and the formation of the twin peaks of Notch activity in vivo. Indeed, the amount of Notch is upregulated and the twin peaks are fused forming a single peak when the function of Delta or late endosomes is compromised. Additionally, we show that the second Notch peak behind the wavefront controls neurogenesis. Thus, intracellular trafficking of Notch orchestrates the temporal dynamics of Notch activity and the temporal patterning of neurogenesis. During Drosophila development, two peaks of Notch activity propagate across the neuroepithelium to generate neuroblasts. Here, the authors show Notch cis-inhibition under the control of intracellular Notch trafficking establishes these two peaks, which temporally control neurogenesis in the brain.
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22
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Saiki W, Ma C, Okajima T, Takeuchi H. Current Views on the Roles of O-Glycosylation in Controlling Notch-Ligand Interactions. Biomolecules 2021; 11:biom11020309. [PMID: 33670724 PMCID: PMC7922208 DOI: 10.3390/biom11020309] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 02/15/2021] [Accepted: 02/16/2021] [Indexed: 12/12/2022] Open
Abstract
The 100th anniversary of Notch discovery in Drosophila has recently passed. The Notch is evolutionarily conserved from Drosophila to humans. The discovery of human-specific Notch genes has led to a better understanding of Notch signaling in development and diseases and will continue to stimulate further research in the future. Notch receptors are responsible for cell-to-cell signaling. They are activated by cell-surface ligands located on adjacent cells. Notch activation plays an important role in determining the fate of cells, and dysregulation of Notch signaling results in numerous human diseases. Notch receptors are primarily activated by ligand binding. Many studies in various fields including genetics, developmental biology, biochemistry, and structural biology conducted over the past two decades have revealed that the activation of the Notch receptor is regulated by unique glycan modifications. Such modifications include O-fucose, O-glucose, and O-N-acetylglucosamine (GlcNAc) on epidermal growth factor-like (EGF) repeats located consecutively in the extracellular domain of Notch receptors. Being fine-tuned by glycans is an important property of Notch receptors. In this review article, we summarize the latest findings on the regulation of Notch activation by glycosylation and discuss future challenges.
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Affiliation(s)
- Wataru Saiki
- Department of Molecular Biochemistry, Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550, Japan; (W.S.); (C.M.); (T.O.)
| | - Chenyu Ma
- Department of Molecular Biochemistry, Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550, Japan; (W.S.); (C.M.); (T.O.)
| | - Tetsuya Okajima
- Department of Molecular Biochemistry, Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550, Japan; (W.S.); (C.M.); (T.O.)
- Institute for Glyco-core Research (iGCORE), Nagoya University, Nagoya, Aichi 464-8601, Japan
| | - Hideyuki Takeuchi
- Department of Molecular Biochemistry, Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550, Japan; (W.S.); (C.M.); (T.O.)
- Institute for Glyco-core Research (iGCORE), Nagoya University, Nagoya, Aichi 464-8601, Japan
- Correspondence: ; Tel.: +81-52-744-2068
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23
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Adonin L, Drozdov A, Barlev NA. Sea Urchin as a Universal Model for Studies of Gene Networks. Front Genet 2021; 11:627259. [PMID: 33552139 PMCID: PMC7854572 DOI: 10.3389/fgene.2020.627259] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2020] [Accepted: 12/10/2020] [Indexed: 01/06/2023] Open
Abstract
The purple sea urchin Strongylocentrotus purpuratus has been used for over 150 years as a model organism in developmental biology. Using this model species, scientists have been able to describe, in detail, the mechanisms of cell cycle control and cell adhesion, fertilization, calcium signaling, cell differentiation, and death. Massive parallel sequencing of the sea urchin genome enabled the deciphering of the main components of gene regulatory networks during the activation of embryonic signaling pathways. This knowledge helped to extrapolate aberrations in somatic cells that may lead to diseases, including cancer in humans. Furthermore, since many, if not all, developmental signaling pathways were shown to be controlled by non-coding RNAs (ncRNAs), the sea urchin organism represents an attractive experimental model. In this review, we discuss the main discoveries in the genetics, genomics, and transcriptomics of sea urchins during embryogenesis with the main focus on the role of ncRNAs. This information may be useful for comparative studies between different organisms, and may help identify new regulatory networks controlled by ncRNAs.
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Affiliation(s)
- Leonid Adonin
- Moscow Institute of Physics and Technology, Dolgoprudny, Russia.,Institute of Environmental and Agricultural Biology (X-BIO), Tyumen State University, Tyumen, Russia.,Orekhovich Institute of Biomedical Chemistry, Moscow, Russia
| | - Anatoliy Drozdov
- Zhirmunsky National Scientific Center of Marine Biology, Far Eastern Branch of the Russian Academy of Sciences, Vladivostok, Russia
| | - Nickolai A Barlev
- Moscow Institute of Physics and Technology, Dolgoprudny, Russia.,Orekhovich Institute of Biomedical Chemistry, Moscow, Russia.,Institute of Cytology, Russian Academy of Sciences, Saint-Petersburg, Russia
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24
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Matsumoto K, Luther KB, Haltiwanger RS. Diseases related to Notch glycosylation. Mol Aspects Med 2020; 79:100938. [PMID: 33341260 DOI: 10.1016/j.mam.2020.100938] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 11/30/2020] [Accepted: 12/03/2020] [Indexed: 12/15/2022]
Abstract
The Notch receptors are a family of transmembrane proteins that mediate direct cell-cell interactions and control numerous cell-fate specifications in humans. The extracellular domains of mammalian Notch proteins contain 29-36 tandem epidermal growth factor-like (EGF) repeats, most of which have O-linked glycan modifications: O-glucose added by POGLUT1, O-fucose added by POFUT1 and elongated by Fringe enzymes, and O-GlcNAc added by EOGT. The extracellular domain is also N-glycosylated. Mutations in the glycosyltransferases modifying Notch have been identified in several diseases, including Dowling-Degos Disease (haploinsufficiency of POFUT1 or POGLUT1), a form of limb-girdle muscular dystrophy (autosomal recessive mutations in POGLUT1), Spondylocostal Dysostosis 3 (autosomal recessive mutations in LFNG), Adams-Oliver syndrome (autosomal recessive mutations in EOGT), and some cancers (amplification, gain or loss-of-function of POFUT1, Fringe enzymes, POGLUT1, MGAT3). Here we review the characteristics of these diseases and potential molecular mechanisms.
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Affiliation(s)
- Kenjiroo Matsumoto
- Complex Carbohydrate Research Center, Department of Biochemistry and Molecular Biology, University of Georgia, 315 Riverbend Road, Athens, GA, 30602, USA
| | - Kelvin B Luther
- Complex Carbohydrate Research Center, Department of Biochemistry and Molecular Biology, University of Georgia, 315 Riverbend Road, Athens, GA, 30602, USA
| | - Robert S Haltiwanger
- Complex Carbohydrate Research Center, Department of Biochemistry and Molecular Biology, University of Georgia, 315 Riverbend Road, Athens, GA, 30602, USA.
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25
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Maier D. Membrane-Anchored Hairless Protein Restrains Notch Signaling Activity. Genes (Basel) 2020; 11:genes11111315. [PMID: 33171957 PMCID: PMC7694644 DOI: 10.3390/genes11111315] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 11/03/2020] [Accepted: 11/04/2020] [Indexed: 11/16/2022] Open
Abstract
The Notch signaling pathway governs cell-to-cell communication in higher eukaryotes. In Drosophila, after cleavage of the transmembrane receptor Notch, the intracellular domain of Notch (ICN) binds to the transducer Suppressor of Hairless (Su(H)) and shuttles into the nucleus to activate Notch target genes. Similarly, the Notch antagonist Hairless transfers Su(H) into the nucleus to repress Notch target genes. With the aim to prevent Su(H) nuclear translocation, Hairless was fused to a transmembrane domain to anchor the protein at membranes. Indeed, endogenous Su(H) co-localized with membrane-anchored Hairless, demonstrating their binding in the cytoplasm. Moreover, adult phenotypes uncovered a loss of Notch activity, in support of membrane-anchored Hairless sequestering Su(H) in the cytosol. A combined overexpression of membrane-anchored Hairless with Su(H) lead to tissue proliferation, which is in contrast to the observed apoptosis after ectopic co-overexpression of the wild-type genes, indicating a shift to a gain of Notch activity. A mixed response, general de-repression of Notch signaling output, plus inhibition at places of highest Notch activity, perhaps reflects Su(H)’s role as activator and repressor, supported by results obtained with the Hairless-binding deficient Su(H)LLL mutant, inducing activation only. Overall, the results strengthen the idea of Su(H) and Hairless complex formation within the cytosolic compartment.
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Affiliation(s)
- Dieter Maier
- Deptartment of General Genetics 190g, University of Hohenheim, Garbenstr. 30, 70599 Stuttgart, Germany
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26
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Fagotto F, Aslemarz A. EpCAM cellular functions in adhesion and migration, and potential impact on invasion: A critical review. Biochim Biophys Acta Rev Cancer 2020; 1874:188436. [PMID: 32976980 DOI: 10.1016/j.bbcan.2020.188436] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 09/19/2020] [Accepted: 09/19/2020] [Indexed: 12/14/2022]
Abstract
EpCAM has long been known as a cell surface protein highly expressed in carcinomas. It has since become one of the key cancer biomarkers. Despite its high fame, its actual role in cancer development is still controversial. Beyond a flurry of correlative studies, which point either to a positive or a negative link with tumour progression, there has been surprisingly few studies on the actual cellular mechanisms of EpCAM and on their functional consequences. Clearly, EpCAM plays multiple important roles, in cell proliferation as well as in cell adhesion and migration. The two latter functions, directly relevant for metastasis, are the focus of this review. We attempt here to bring together the available experimental data to build a global coherent view of EpCAM functions. We also include in this overview EpCAM2/Trop2, the close relative of EpCAM. At the core of EpCAM (and EpCAM2/Trop2) function stands the ability to repress contractility of the actomyosin cell cortex. This activity appears to involve direct inhibition by EpCAM of members of the novel PKC family and of a specific downstream PKD-Erk cascade. We will discuss how this activity can result in a variety of adhesive and migratory phenotypes, thus potentially explaining at least part of the apparent inconsistencies between different studies. The picture remains fragmented, and we will highlight some of the conflicting evidence and the many unsolved issues, starting with the controversy around its original description as a cell-cell adhesion molecule.
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Affiliation(s)
- François Fagotto
- CRBM, University of Montpellier and CNRS, Montpellier 34293, France.
| | - Azam Aslemarz
- CRBM, University of Montpellier and CNRS, Montpellier 34293, France; Department of Biology, McGill University, Montreal, QC H3A1B1, Canada
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27
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Pandey A, Harvey BM, Lopez MF, Ito A, Haltiwanger RS, Jafar-Nejad H. Glycosylation of Specific Notch EGF Repeats by O-Fut1 and Fringe Regulates Notch Signaling in Drosophila. Cell Rep 2020; 29:2054-2066.e6. [PMID: 31722217 PMCID: PMC6866671 DOI: 10.1016/j.celrep.2019.10.027] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 09/13/2019] [Accepted: 10/07/2019] [Indexed: 12/27/2022] Open
Abstract
Fringe glycosyltransferases differentially modulate the binding of Notch receptors to Delta/DLL versus Serrate/Jagged ligands by adding GlcNAc to O-linked fucose on Notch epidermal growth factor-like (EGF) repeats. Although Notch has 22 O-fucosylation sites, the biologically relevant sites affecting Notch activity during animal development in vivo in the presence or absence of Fringe are not known. Using a variety of assays, we find important roles in Drosophila Notch signaling for GlcNAc-fucose-O glycans on three sites: EGF8, EGF9, and EGF12. O-Fucose monosaccharide on EGF12 (in the absence of Fringe) is essential for Delta-mediated lateral inhibition in embryos. However, wing vein development depends on the addition of GlcNAc to EGF8 and EGF12 by Fringe, with a minor contribution from EGF9. Fringe modifications of EGF8 and EGF12 together prevent Notch from cis-inhibiting Serrate, thereby promoting normal wing margin formation. Our work shows the combinatorial and context-dependent roles of GlcNAc-fucose-O glycans on these sites in Drosophila Notch-ligand interactions. POFUT1/O-Fut1 and Fringe glycosyltransferases regulate Notch signaling by adding fucose and GlcNAc, respectively, to Notch EGF repeats. Using in vitro and in vivo experiments, Pandey et al. define the critical target sites of these enzymes on Drosophila Notch and determine the distinct roles of each sugar in Notch-dependent processes.
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Affiliation(s)
- Ashutosh Pandey
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Beth M Harvey
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794, USA
| | - Mario F Lopez
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Atsuko Ito
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA
| | - Robert S Haltiwanger
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794, USA; Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA.
| | - Hamed Jafar-Nejad
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030, USA.
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28
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Jin H, Yoda S, Liu L, Kojima T, Fujiwara H. Notch and Delta Control the Switch and Formation of Camouflage Patterns in Caterpillars. iScience 2020; 23:101315. [PMID: 32650115 PMCID: PMC7347997 DOI: 10.1016/j.isci.2020.101315] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 05/21/2020] [Accepted: 06/20/2020] [Indexed: 12/25/2022] Open
Abstract
In most Papilio species, a younger larva mimics bird droppings but changes its pattern to match host plant colors in its final instar. This change is determined by juvenile hormone (JH) during the JH-sensitive period (JHSP) early in the fourth instar. Recently, we found that homeobox genes control the pre-pattern formation specifically during JHSP, but the molecular mechanisms underlying final patterning and pigmentation at molt are unknown. By knockdown of Delta and Notch in Papilio xuthus larvae, we here showed that these genes define the edge and pigmentation area in final patterns, during and even after JHSP, suggesting that they bridge the JHSP and molt. Knockdown of Delta in Papilio machaon led to similar phenotypic changes, and knockdown of Notch caused pigmentation loss in twin spots of the silkworm Multilunar (L) mutant. Our findings suggest the importance of the Notch signaling pathway in caterpillars' adaptive evolution of color pattern formation. Notch and its ligand Delta regulate camouflage patterns of caterpillars They define edge and pigmentation area in Papilio xuthus final larval patterns They are suggested to bridge the juvenile hormone response period and final molt Notch signaling pathway is important for caterpillars' color pattern evolution
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Affiliation(s)
- Hongyuan Jin
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba 277-8562, Japan
| | - Shinichi Yoda
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba 277-8562, Japan
| | - Liang Liu
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba 277-8562, Japan
| | - Tetsuya Kojima
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba 277-8562, Japan
| | - Haruhiko Fujiwara
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba 277-8562, Japan.
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29
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Griffiths NW, Del Bel LM, Wilk R, Brill JA. Cellular homeostasis in the Drosophila retina requires the lipid phosphatase Sac1. Mol Biol Cell 2020; 31:1183-1199. [PMID: 32186963 PMCID: PMC7353163 DOI: 10.1091/mbc.e20-02-0161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The complex functions of cellular membranes, and thus overall cell physiology, depend on the distribution of crucial lipid species. Sac1 is an essential, conserved, ER-localized phosphatase whose substrate, phosphatidylinositol 4-phosphate (PI4P), coordinates secretory trafficking and plasma membrane function. PI4P from multiple pools is delivered to Sac1 by oxysterol-binding protein and related proteins in exchange for other lipids and sterols, which places Sac1 at the intersection of multiple lipid distribution pathways. However, much remains unknown about the roles of Sac1 in subcellular homeostasis and organismal development. Using a temperature-sensitive allele (Sac1ts), we show that Sac1 is required for structural integrity of the Drosophila retinal floor. The βps-integrin Myospheroid, which is necessary for basal cell adhesion, is mislocalized in Sac1ts retinas. In addition, the adhesion proteins Roughest and Kirre, which coordinate apical retinal cell patterning at an earlier stage, accumulate within Sac1ts retinal cells due to impaired endo-lysosomal degradation. Moreover, Sac1 is required for ER homeostasis in Drosophila retinal cells. Together, our data illustrate the importance of Sac1 in regulating multiple aspects of cellular homeostasis during tissue development.
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Affiliation(s)
- Nigel W Griffiths
- Cell Biology Program, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Lauren M Del Bel
- Cell Biology Program, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Ronit Wilk
- Cell Biology Program, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada
| | - Julie A Brill
- Cell Biology Program, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
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30
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Boukhatmi H, Martins T, Pillidge Z, Kamenova T, Bray S. Notch Mediates Inter-tissue Communication to Promote Tumorigenesis. Curr Biol 2020; 30:1809-1820.e4. [DOI: 10.1016/j.cub.2020.02.088] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 02/03/2020] [Accepted: 02/27/2020] [Indexed: 12/19/2022]
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31
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Das P, Salazar JL, Li-Kroeger D, Yamamoto S, Nakamura M, Sasamura T, Inaki M, Masuda W, Kitagawa M, Yamakawa T, Matsuno K. Maternal almondex, a neurogenic gene, is required for proper subcellular Notch distribution in early Drosophila embryogenesis. Dev Growth Differ 2019; 62:80-93. [PMID: 31782145 DOI: 10.1111/dgd.12639] [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: 09/27/2019] [Accepted: 10/08/2019] [Indexed: 01/03/2023]
Abstract
Notch signaling plays crucial roles in the control of cell fate and physiology through local cell-cell interactions. The core processes of Notch signal transduction are well established, but the mechanisms that fine-tune the pathway in various developmental and post-developmental contexts are less clear. Drosophila almondex, which encodes an evolutionarily conserved double-pass transmembrane protein, was identified in the 1970s as a maternal-effect gene that regulates Notch signaling in certain contexts, but its mechanistic function remains obscure. In this study, we examined the role of almondex in Notch signaling during early Drosophila embryogenesis. We found that in addition to being required for lateral inhibition in the neuroectoderm, almondex is also partially required for Notch signaling-dependent single-minded expression in the mesectoderm. Furthermore, we found that almondex is required for proper subcellular Notch receptor distribution in the neuroectoderm, specifically during mid-stage 5 development. The absence of maternal almondex during this critical window of time caused Notch to accumulate abnormally in cells in a mesh-like pattern. This phenotype did not include any obvious change in subcellular Delta ligand distribution, suggesting that it does not result from a general vesicular-trafficking defect. Considering that dynamic Notch trafficking regulates signal output to fit the specific context, we speculate that almondex may facilitate Notch activation by regulating intracellular Notch receptor distribution during early embryogenesis.
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Affiliation(s)
- Puspa Das
- Department of Biological Sciences, Graduate School of Science, Osaka University, Osaka, Japan
| | - Jose L Salazar
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - David Li-Kroeger
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Shinya Yamamoto
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA.,Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA.,Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX, USA
| | - Mitsutoshi Nakamura
- Department of Biological Sciences, Graduate School of Science, Osaka University, Osaka, Japan
| | - Takeshi Sasamura
- Department of Biological Sciences, Graduate School of Science, Osaka University, Osaka, Japan
| | - Mikiko Inaki
- Department of Biological Sciences, Graduate School of Science, Osaka University, Osaka, Japan
| | - Wataru Masuda
- Department of Pathology, Saitama Medical Center, Saitama Medical University, Saitama, Japan
| | - Motoo Kitagawa
- Department of Biochemistry, International University of Health and Welfare, School of Medicine, Chiba, Japan
| | - Tomoko Yamakawa
- Department of Biological Sciences, Graduate School of Science, Osaka University, Osaka, Japan
| | - Kenji Matsuno
- Department of Biological Sciences, Graduate School of Science, Osaka University, Osaka, Japan
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32
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Jarrett SM, Seegar TCM, Andrews M, Adelmant G, Marto JA, Aster JC, Blacklow SC. Extension of the Notch intracellular domain ankyrin repeat stack by NRARP promotes feedback inhibition of Notch signaling. Sci Signal 2019; 12:12/606/eaay2369. [PMID: 31690634 DOI: 10.1126/scisignal.aay2369] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Canonical Notch signaling relies on regulated proteolysis of the receptor Notch to generate a nuclear effector that induces the transcription of Notch-responsive genes. In higher organisms, one Notch-responsive gene that is activated in many different cell types encodes the Notch-regulated ankyrin repeat protein (NRARP), which acts as a negative feedback regulator of Notch responses. Here, we showed that NRARP inhibited the growth of Notch-dependent T cell acute lymphoblastic leukemia (T-ALL) cell lines and bound directly to the core Notch transcriptional activation complex (NTC), requiring both the transcription factor RBPJ and the Notch intracellular domain (NICD), but not Mastermind-like proteins or DNA. The crystal structure of an NRARP-NICD1-RBPJ-DNA complex, determined to 3.75 Å resolution, revealed that the assembly of NRARP-NICD1-RBPJ complexes relied on simultaneous engagement of RBPJ and NICD1, with the three ankyrin repeats of NRARP extending the Notch1 ankyrin repeat stack. Mutations at the NRARP-NICD1 interface disrupted entry of the proteins into NTCs and abrogated feedback inhibition in Notch signaling assays in cultured cells. Forced expression of NRARP reduced the abundance of NICD in cells, suggesting that NRARP may promote the degradation of NICD. These studies establish the structural basis for NTC engagement by NRARP and provide insights into a critical negative feedback mechanism that regulates Notch signaling.
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Affiliation(s)
- Sanchez M Jarrett
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
| | - Tom C M Seegar
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
| | - Mark Andrews
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA
| | - Guillaume Adelmant
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA.,Department of Pathology, Brigham and Women's Hospital, Boston, MA 02215, USA.,Department of Oncologic Pathology and Blais Proteomic Center, Dana-Farber Cancer Institute, Boston, MA 02215, USA
| | - Jarrod A Marto
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA.,Department of Pathology, Brigham and Women's Hospital, Boston, MA 02215, USA.,Department of Oncologic Pathology and Blais Proteomic Center, Dana-Farber Cancer Institute, Boston, MA 02215, USA
| | - Jon C Aster
- Department of Pathology, Brigham and Women's Hospital, Boston, MA 02215, USA
| | - Stephen C Blacklow
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA. .,Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA
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33
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Song EK, Jeon J, Jang DG, Kim HE, Sim HJ, Kwon KY, Medina-Ruiz S, Jang HJ, Lee AR, Rho JG, Lee HS, Kim SJ, Park CY, Myung K, Kim W, Kwon T, Yang S, Park TJ. ITGBL1 modulates integrin activity to promote cartilage formation and protect against arthritis. Sci Transl Med 2019; 10:10/462/eaam7486. [PMID: 30305454 DOI: 10.1126/scitranslmed.aam7486] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Accepted: 09/20/2018] [Indexed: 11/02/2022]
Abstract
Developing and mature chondrocytes constantly interact with and remodel the surrounding extracellular matrix (ECM). Recent research indicates that integrin-ECM interaction is differentially regulated during cartilage formation (chondrogenesis). Integrin signaling is also a key source of the catabolic reactions responsible for joint destruction in both rheumatoid arthritis and osteoarthritis. However, we do not understand how chondrocytes dynamically regulate integrin signaling in such an ECM-rich environment. Here, we found that developing chondrocytes express integrin-β-like 1 (Itgbl1) at specific stages, inhibiting integrin signaling and promoting chondrogenesis. Unlike cytosolic integrin inhibitors, ITGBL1 is secreted and physically interacts with integrins to down-regulate activity. We observed that Itgbl1 expression was strongly reduced in the damaged articular cartilage of patients with osteoarthritis (OA). Ectopic expression of Itgbl1 protected joint cartilage against OA development in the destabilization of the medial meniscus-induced OA mouse model. Our results reveal ITGBL1 signaling as an underlying mechanism of protection against destructive cartilage disorders and suggest the potential therapeutic utility of targeting ITGBL1 to modulate integrin signaling in human disease.
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Affiliation(s)
- Eun Kyung Song
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea.,Center for Genomic Integrity, Institute for Basic Science, Ulsan 44919, Republic of Korea
| | - Jimin Jeon
- Department of Pharmacology, Ajou University School of Medicine, Suwon 16499, Republic of Korea.,Department of Biomedical Sciences, Graduate School, Ajou University, Suwon 16499, Republic of Korea.,CIRNO, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Dong Gil Jang
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| | - Ha Eun Kim
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| | - Hyo Jung Sim
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| | - Keun Yeong Kwon
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| | - Sofia Medina-Ruiz
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA
| | - Hyun-Jun Jang
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| | - Ah Reum Lee
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| | - Jun Gi Rho
- Department of Molecular Science and Technology, Ajou University, Suwon 16499, Republic of Korea
| | - Hyun-Shik Lee
- KNU-Center for Nonlinear Dynamics, CMRI, School of Life Sciences, BK21 Plus KNU Creative BioResearch Group, College of Natural Sciences, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Seok Jung Kim
- Department of Orthopaedic Surgery, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea
| | - Chan Young Park
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| | - Kyungjae Myung
- Center for Genomic Integrity, Institute for Basic Science, Ulsan 44919, Republic of Korea
| | - Wook Kim
- Department of Molecular Science and Technology, Ajou University, Suwon 16499, Republic of Korea
| | - Taejoon Kwon
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| | - Siyoung Yang
- Department of Pharmacology, Ajou University School of Medicine, Suwon 16499, Republic of Korea. .,Department of Biomedical Sciences, Graduate School, Ajou University, Suwon 16499, Republic of Korea.,CIRNO, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Tae Joo Park
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea. .,Center for Genomic Integrity, Institute for Basic Science, Ulsan 44919, Republic of Korea
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34
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Mak DW, Li S, Minchom A. Challenging the recalcitrant disease—developing molecularly driven treatments for small cell lung cancer. Eur J Cancer 2019; 119:132-150. [DOI: 10.1016/j.ejca.2019.04.037] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 04/11/2019] [Accepted: 04/26/2019] [Indexed: 12/29/2022]
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35
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Lu JB, Lou YH, Li LC, Zhang XY, Luo XM, Zhang CX. Egf-like gene is essential for cuticle metabolism in the brown planthopper. JOURNAL OF INSECT PHYSIOLOGY 2019; 116:90-99. [PMID: 31063731 DOI: 10.1016/j.jinsphys.2019.05.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 05/02/2019] [Accepted: 05/02/2019] [Indexed: 06/09/2023]
Abstract
Using the mass spectrometry analysis of cuticle casts of brown planthopper (BPH, Nilaparvata lugens) and transcriptome analysis of BPH tissues, we identified a gigantic gene (50,922 bp, 16,973 aa) tentatively called Nlegf-like. Multiple transcripts were found. Nlegf-like encodes an integral membrane protein of 16,973 amino acid residues with 260 EGF-like repeats and 16 Ca2+-binding EGF repeats type (cbEGFs) in the extracellular portion. Nlegf-like was highly expressed in the integument and tended to peak at the middle stage or late stage of each nymph instar. Phylogenetic analysis showed this gene is conserved in many other insects. Different double-stranded RNA-mediated RNA interference targeting eight different regions of the Nlegf-like gene resulted in abnormal cuticle formation or molting and lethal phenotypes. Transmission electron microscopy revealed that the newly formed endocuticle was significantly thinner for RNAi-treated BPHs with phenotype of contracted abdomen, or the old cuticle could not be digested sufficiently for those with phenotype of slender body shape or died with molting difficulty when compared with the control group. We suggest that the Nlegf-like is crucial for metabolism of the cuticle in BPH molting.
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Affiliation(s)
- Jia-Bao Lu
- State Key Laboratory of Rice Biology and Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insect Pests, Institute of Insect Science, Zhejiang University, Hangzhou 310058, China
| | - Yi-Han Lou
- State Key Laboratory of Rice Biology and Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insect Pests, Institute of Insect Science, Zhejiang University, Hangzhou 310058, China
| | - Ling-Chen Li
- State Key Laboratory of Rice Biology and Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insect Pests, Institute of Insect Science, Zhejiang University, Hangzhou 310058, China
| | - Xiao-Ya Zhang
- State Key Laboratory of Rice Biology and Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insect Pests, Institute of Insect Science, Zhejiang University, Hangzhou 310058, China
| | - Xu-Mei Luo
- State Key Laboratory of Rice Biology and Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insect Pests, Institute of Insect Science, Zhejiang University, Hangzhou 310058, China
| | - Chuan-Xi Zhang
- State Key Laboratory of Rice Biology and Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insect Pests, Institute of Insect Science, Zhejiang University, Hangzhou 310058, China.
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36
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Lehotzky D, Zupanc GKH. Cellular Automata Modeling of Stem-Cell-Driven Development of Tissue in the Nervous System. Dev Neurobiol 2019; 79:497-517. [PMID: 31102334 DOI: 10.1002/dneu.22686] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 04/23/2019] [Accepted: 05/02/2019] [Indexed: 12/12/2022]
Abstract
Mathematical and computational modeling enables biologists to integrate data from observations and experiments into a theoretical framework. In this review, we describe how developmental processes associated with stem-cell-driven growth of tissue in both the embryonic and adult nervous system can be modeled using cellular automata (CA). A cellular automaton is defined by its discrete nature in time, space, and state. The discrete space is represented by a uniform grid or lattice containing agents that interact with other agents within their local neighborhood. This possibility of local interactions of agents makes the cellular automata approach particularly well suited for studying through modeling how complex patterns at the tissue level emerge from fundamental developmental processes (such as proliferation, migration, differentiation, and death) at the single-cell level. As part of this review, we provide a primer for how to define biologically inspired rules governing these processes so that they can be implemented into a CA model. We then demonstrate the power of the CA approach by presenting simulations (in the form of figures and movies) based on building models of three developmental systems: the formation of the enteric nervous system through invasion by neural crest cells; the growth of normal and tumorous neurospheres induced by proliferation of adult neural stem/progenitor cells; and the neural fate specification through lateral inhibition of embryonic stem cells in the neurogenic region of Drosophila.
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Affiliation(s)
- Dávid Lehotzky
- Laboratory of Neurobiology, Department of Biology, Northeastern University, Boston, Massachusetts
| | - Günther K H Zupanc
- Laboratory of Neurobiology, Department of Biology, Northeastern University, Boston, Massachusetts
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37
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Reinhardt S, Schuck F, Stoye N, Hartmann T, Grimm MOW, Pflugfelder G, Endres K. Transcriptional repression of the ectodomain sheddase ADAM10 by TBX2 and potential implication for Alzheimer's disease. Cell Mol Life Sci 2019; 76:1005-1025. [PMID: 30599067 PMCID: PMC11105458 DOI: 10.1007/s00018-018-2998-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 12/11/2018] [Accepted: 12/12/2018] [Indexed: 12/15/2022]
Abstract
BACKGROUND The ADAM10-mediated cleavage of transmembrane proteins regulates cellular processes such as proliferation or migration. Substrate cleavage by ADAM10 has also been implicated in pathological situations such as cancer or Morbus Alzheimer. Therefore, identifying endogenous molecules, which modulate the amount and consequently the activity of ADAM10, might contribute to a deeper understanding of the enzyme's role in both, physiology and pathology. METHOD To elucidate the underlying cellular mechanism of the TBX2-mediated repression of ADAM10 gene expression, we performed overexpression, RNAi-mediated knockdown and pharmacological inhibition studies in the human neuroblastoma cell line SH-SY5Y. Expression analysis was conducted by e.g. real-time RT-PCR or western blot techniques. To identify the binding region of TBX2 within the ADAM10 promoter, we used luciferase reporter assay on deletion constructs and EMSA/WEMSA experiments. In addition, we analyzed a TBX2 loss-of-function Drosophila model regarding the expression of ADAM10 orthologs by qPCR. Furthermore, we quantified the mRNA level of TBX2 in post-mortem brain tissue of AD patients. RESULTS Here, we report TBX2 as a transcriptional repressor of ADAM10 gene expression: both, the DNA-binding domain and the repression domain of TBX2 were necessary to effect transcriptional repression of ADAM10 in neuronal SH-SY5Y cells. This regulatory mechanism required HDAC1 as a co-factor of TBX2. Transcriptional repression was mediated by two functional TBX2 binding sites within the core promoter sequence (- 315 to - 286 bp). Analysis of a TBX2 loss-of-function Drosophila model revealed that kuzbanian and kuzbanian-like, orthologs of ADAM10, were derepressed compared to wild type. Vice versa, analysis of cortical brain samples of AD-patients, which showed reduced ADAM10 mRNA levels, revealed a 2.5-fold elevation of TBX2, while TBX3 and TBX21 levels were not affected. CONCLUSION Our results characterize TBX2 as a repressor of ADAM10 gene expression and suggest that this regulatory interaction is conserved across tissues and species.
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Affiliation(s)
- Sven Reinhardt
- Department of Psychiatry and Psychotherapy, University Medical Center of the Johannes Gutenberg University Mainz, Untere Zahlbacher Strasse 8, 55131, Mainz, Germany
| | - Florian Schuck
- Department of Psychiatry and Psychotherapy, University Medical Center of the Johannes Gutenberg University Mainz, Untere Zahlbacher Strasse 8, 55131, Mainz, Germany
| | - Nicolai Stoye
- Department of Psychiatry and Psychotherapy, University Medical Center of the Johannes Gutenberg University Mainz, Untere Zahlbacher Strasse 8, 55131, Mainz, Germany
| | - Tobias Hartmann
- Deutsches Institut für Demenz Prävention (DIDP), Neurodegeneration and Neurobiology, Saarland University, Kirrbergerstrasse 1, 66421, Homburg, Saar, Germany
- Experimental Neurology, Saarland University, Kirrbergerstrasse 1, 66421, Homburg, Saar, Germany
| | - Marcus O W Grimm
- Deutsches Institut für Demenz Prävention (DIDP), Neurodegeneration and Neurobiology, Saarland University, Kirrbergerstrasse 1, 66421, Homburg, Saar, Germany
- Experimental Neurology, Saarland University, Kirrbergerstrasse 1, 66421, Homburg, Saar, Germany
| | - Gert Pflugfelder
- Institute of Developmental Biology and Neurobiology, Johannes Gutenberg University, Becherweg 32, 55128, Mainz, Germany
| | - Kristina Endres
- Department of Psychiatry and Psychotherapy, University Medical Center of the Johannes Gutenberg University Mainz, Untere Zahlbacher Strasse 8, 55131, Mainz, Germany.
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Cui Q, Xing J, Gu Y, Nan X, Ma W, Chen Y, Zhao H. GXYLT2 accelerates cell growth and migration by regulating the Notch pathway in human cancer cells. Exp Cell Res 2019; 376:1-10. [PMID: 30716301 DOI: 10.1016/j.yexcr.2019.01.023] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 01/27/2019] [Accepted: 01/31/2019] [Indexed: 12/14/2022]
Abstract
Glucoside xylosyltransferase2 (GXYLT2), a member of the human α-1,3-D-xylosyltransferases, functions to modify the first xylose to the O-Glucose residue on epidermal growth factor (EGF) repeats of Notch receptors. It is well-established that the Notch signaling pathway plays a critical role in proper development and homeostasis. However, the regulatory role of EGF xylosylation in Notch signaling and different cell activities in human cells remains unknown. In this study, we showed that knockdown of GXYLT2 suppressed human cell proliferation and induced G1/S phase cell cycle arrest. GXYLT2 downregulation also inhibited cell migration and invasion, whereas the overexpression of GXYLT2 had the opposite effects. Additionally, GXYLT2 activated Notch signaling and promoted the phosphorylation of MAPKs but not PI3K and Akt. Taken together, our findings indicated that GXYLT2 plays an important role in cell activities via regulation of the Notch signaling.
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Affiliation(s)
- Qi Cui
- Department of Medical Genetics, Peking University School of Basic Medical Sciences, Beijing 100191, China; Peking University Center for Human Disease Genomics, Beijing 100191, China
| | - Jinhao Xing
- Department of Medical Genetics, Peking University School of Basic Medical Sciences, Beijing 100191, China; Peking University Center for Human Disease Genomics, Beijing 100191, China
| | - Yajuan Gu
- Department of Medical Genetics, Peking University School of Basic Medical Sciences, Beijing 100191, China; Peking University Center for Human Disease Genomics, Beijing 100191, China
| | - Xu Nan
- Department of Medical Genetics, Peking University School of Basic Medical Sciences, Beijing 100191, China; Peking University Center for Human Disease Genomics, Beijing 100191, China
| | - Wenping Ma
- Department of Medical Genetics, Peking University School of Basic Medical Sciences, Beijing 100191, China; Peking University Center for Human Disease Genomics, Beijing 100191, China
| | - Yingyu Chen
- Peking University Center for Human Disease Genomics, Beijing 100191, China; Department of Immunology, Peking University School of Basic Medical Science, Key Laboratory of Medical Immunology, Beijing 100191, China
| | - Hongshan Zhao
- Department of Medical Genetics, Peking University School of Basic Medical Sciences, Beijing 100191, China; Peking University Center for Human Disease Genomics, Beijing 100191, China.
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Henrique D, Schweisguth F. Mechanisms of Notch signaling: a simple logic deployed in time and space. Development 2019; 146:146/3/dev172148. [PMID: 30709911 DOI: 10.1242/dev.172148] [Citation(s) in RCA: 107] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Most cells in our body communicate during development and throughout life via Notch receptors and their ligands. Notch receptors relay information from the cell surface to the genome via a very simple mechanism, yet Notch plays multiple roles in development and disease. Recent studies suggest that this versatility in Notch function may not necessarily arise from complex and context-dependent integration of Notch signaling with other developmental signals, but instead arises, in part, from signaling dynamics. Here, we review recent findings on the core Notch signaling mechanism and discuss how spatial-temporal dynamics contribute to Notch signaling output.
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Affiliation(s)
- Domingos Henrique
- Instituto de Histologia e Biologia do Desenvolvimento and Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Av. Prof. Egaz Moniz, 1649-028 Lisboa, Portugal
| | - François Schweisguth
- Institut Pasteur, Department of Developmental and Stem Cell Biology, F-75015 Paris, France .,CNRS, UMR3738, F-75015 Paris, France
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40
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Fic W, Faria C, St Johnston D. IMP regulates Kuzbanian to control the timing of Notch signalling in Drosophila follicle cells. Development 2019; 146:dev.168963. [PMID: 30635283 PMCID: PMC6361131 DOI: 10.1242/dev.168963] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Accepted: 12/19/2018] [Indexed: 12/31/2022]
Abstract
The timing of Drosophila egg chamber development is controlled by a germline Delta signal that activates Notch in the follicle cells to induce them to cease proliferation and differentiate. Here, we report that follicle cells lacking the RNA-binding protein IMP go through one extra division owing to a delay in the Delta-dependent S2 cleavage of Notch. The timing of Notch activation has previously been shown to be controlled by cis-inhibition by Delta in the follicle cells, which is relieved when the miRNA pathway represses Delta expression. imp mutants are epistatic to Delta mutants and give an additive phenotype with belle and Dicer-1 mutants, indicating that IMP functions independently of both cis-inhibition and the miRNA pathway. We find that the imp phenotype is rescued by overexpression of Kuzbanian, the metalloprotease that mediates the Notch S2 cleavage. Furthermore, Kuzbanian is not enriched at the apical membrane in imp mutants, accumulating instead in late endosomes. Thus, IMP regulates Notch signalling by controlling the localisation of Kuzbanian to the apical domain, where Notch cleavage occurs, revealing a novel regulatory step in the Notch pathway.
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Affiliation(s)
| | | | - Daniel St Johnston
- The Gurdon Institute and The Department of Genetics, University of Cambridge, Tennis Court Rd, Cambridge CB2 1QN, UK
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41
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Luhur A, Klueg KM, Zelhof AC. Generating and working with Drosophila cell cultures: Current challenges and opportunities. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2018; 8:e339. [PMID: 30561900 DOI: 10.1002/wdev.339] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 10/30/2018] [Accepted: 11/21/2018] [Indexed: 12/26/2022]
Abstract
The use of Drosophila cell cultures has positively impacted both fundamental and biomedical research. The most widely used cell lines: Schneider, Kc, the CNS and imaginal disc lines continue to be the choice for many applications. Drosophila cell lines provide a homogenous source of cells suitable for biochemical experimentations, transcriptomics, functional genomics, and biomedical applications. They are amenable to RNA interference and serve as a platform for high-throughput screens to identify relevant candidate genes or drugs for any biological process. Currently, CRISPR-based functional genomics are also being developed for Drosophila cell lines. Even though many uniquely derived cell lines exist, cell genetic techniques such the transgenic UAS-GAL4-based RasV12 oncogene expression, CRISPR-Cas9 editing and recombination mediated cassette exchange are likely to drive the establishment of many more lines from specific tissues, cells, or genotypes. However, the pace of creating new lines is hindered by several factors inherent to working with Drosophila cell cultures: single cell cloning, optimal media formulations and culture conditions capable of supporting lines from novel tissue sources or genotypes. Moreover, even though many Drosophila cell lines are morphologically and transcriptionally distinct it may be necessary to implement a standard for Drosophila cell line authentication, ensuring the identity and purity of each cell line. Altogether, recent advances and a standardized authentication effort should improve the utility of Drosophila cell cultures as a relevant model for fundamental and biomedical research. This article is categorized under: Technologies > Analysis of Cell, Tissue, and Animal Phenotypes.
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Affiliation(s)
- Arthur Luhur
- Department of Biology, Drosophila Genomics Resource Center, Indiana University Bloomington, Bloomington, Indiana
| | - Kristin M Klueg
- Department of Biology, Drosophila Genomics Resource Center, Indiana University Bloomington, Bloomington, Indiana
| | - Andrew C Zelhof
- Department of Biology, Drosophila Genomics Resource Center, Indiana University Bloomington, Bloomington, Indiana
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Wang J, Zhang K, Liu Z, Wang T, Shi F, Zhang Y, Su J, Jia Y. Upregulated delta-like protein 3 expression is a diagnostic and prognostic marker in endometrial cancer: A retrospective study. Medicine (Baltimore) 2018; 97:e13442. [PMID: 30572444 PMCID: PMC6320086 DOI: 10.1097/md.0000000000013442] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Accepted: 11/05/2018] [Indexed: 12/19/2022] Open
Abstract
Upregulated delta-like protein 3 (DLL3) functions as a Notch ligand and has been a target for cancer therapy. The present study assessed DLL3 expression as a tumor marker for endometrial cancer.RNA-Seq expression data and clinicopathologic records from 545 patients with endometrial cancer were downloaded from The Cancer Genome Atlas database. Mann-Whitney U and logistic regression tests were applied to associate the level of DLL3 expression with clinical variables from the patients. Kaplan-Meier curves and log-rank tests were performed to compare overall survival of patients stratified by different levels of DLL3 expression. Multivariate Cox regression tests were used to analyze independent predictors for endometrial cancer. DLL3 expression was upregulated in endometrial cancer tissues compared to para-carcinoma tissues (P = .0003). High DLL3 expression was associated with the age of patients (odds ratio [OR] = 1.74), advanced stages of the International Federation of Gynecology and Obstetrics system (OR = 2.9), grade III/IV (OR = 5.1), myometrial invasion (OR = 2.2), pelvic involvement (OR = 12.9), and para-aortic lymph node metastasis (OR = 9.9) (all P ≤ .001). Furthermore, upregulated DLL3 expression was also associated with a median overall survival of 112 months (HR = 1.85, confidence internal 1.202-2.846, P = .005). The multivariate analysis showed that DLL3 overexpression and advanced tumor stages, grades, and lymph node metastases were all independent prognostic predictors for endometrial cancer.The DLL3 expression could be a potential and novel tumor marker for early diagnosis and an independent predictor of poor survival for patients with endometrial cancer.
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43
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Matsumoto K, Haltiwanger RS. What are the Real Functions of O-Glycan Modifications of Notch? TRENDS GLYCOSCI GLYC 2018. [DOI: 10.4052/tigg.1720.4j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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44
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Matsumoto K, Haltiwanger RS. What are the Real Functions of O-Glycan Modifications of Notch? TRENDS GLYCOSCI GLYC 2018. [DOI: 10.4052/tigg.1720.4e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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45
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Enhanced Delta-Notch Lateral Inhibition Model Incorporating Intracellular Notch Heterogeneity and Tension-Dependent Rate of Delta-Notch Binding that Reproduces Sprouting Angiogenesis Patterns. Sci Rep 2018; 8:9519. [PMID: 29934586 PMCID: PMC6015056 DOI: 10.1038/s41598-018-27645-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 06/06/2018] [Indexed: 01/17/2023] Open
Abstract
Endothelial cells adopt unique cell fates during sprouting angiogenesis, differentiating into tip or stalk cells. The fate selection process is directed by Delta-Notch lateral inhibition pathway. Classical Delta-Notch models produce a spatial pattern of tip cells separated by a single stalk cell, or the salt-and-pepper pattern. However, classical models cannot explain alternative tip-stalk patterning, such as tip cells that are separated by two or more stalk cells. We show that lateral inhibition models involving only Delta and Notch proteins can also recapitulate experimental tip-stalk patterns by invoking two mechanisms, specifically, intracellular Notch heterogeneity and tension-dependent rate of Delta-Notch binding. We introduce our computational model and analysis where we establish that our enhanced Delta-Notch lateral inhibition model can recapitulate a greater variety of tip-stalk patterning which is previously not possible using classical lateral inhibition models. In our enhanced Delta-Notch lateral inhibition model, we observe the existence of a hybrid cell type displaying intermediate tip and stalk cells’ characteristics. We validate the existence of such hybrid cells by immuno-staining of endothelial cells with tip cell markers, Delta and CD34, which substantiates our enhanced model.
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Insight into Notch Signaling Steps That Involve pecanex from Dominant-Modifier Screens in Drosophila. Genetics 2018; 209:1099-1119. [PMID: 29853475 DOI: 10.1534/genetics.118.300935] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Accepted: 05/22/2018] [Indexed: 12/14/2022] Open
Abstract
Notch signaling plays crucial roles in intercellular communications. In Drosophila, the pecanex (pcx) gene, which encodes an evolutionarily conserved multi-pass transmembrane protein, appears to be required to activate Notch signaling in some contexts, especially during neuroblast segregation in the neuroectoderm. Although Pcx has been suggested to contribute to endoplasmic reticulum homeostasis, its functions remain unknown. Here, to elucidate these roles, we performed genetic modifier screens of pcx We found that pcx heterozygotes lacking its maternal contribution exhibit cold-sensitive lethality, which is attributed to a reduction in Notch signaling at decreased temperatures. Using sets of deletions that uncover most of the second and third chromosomes, we identified four enhancers and two suppressors of the pcx cold-sensitive lethality. Among these, five genes encode known Notch-signaling components: big brain, Delta (Dl), neuralized (neur), Brother of Bearded A (BobA), a member of the Bearded (Brd) family, and N-ethylmaleimide-sensitive factor 2 (Nsf2). We showed that BobA suppresses Dl endocytosis during neuroblast segregation in the neuroectoderm, as Brd family genes reportedly do in the mesoderm for mesectoderm specification. Analyses of Nsf2, a key regulator of vesicular fusion, suggested a novel role in neuroblast segregation, which is distinct from Nsf2's previously reported role in imaginal tissues. Finally, jim lovell, which encodes a potential transcription factor, may play a role in Notch signaling during neuroblast segregation. These results reveal new research avenues for Pcx functions and Notch signaling.
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47
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Del Bel LM, Griffiths N, Wilk R, Wei HC, Blagoveshchenskaya A, Burgess J, Polevoy G, Price JV, Mayinger P, Brill JA. The phosphoinositide phosphatase Sac1 regulates cell shape and microtubule stability in the developing Drosophila eye. Development 2018; 145:dev151571. [PMID: 29752385 PMCID: PMC6031321 DOI: 10.1242/dev.151571] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Accepted: 04/30/2018] [Indexed: 12/15/2022]
Abstract
Epithelial patterning in the developing Drosophila melanogaster eye requires the Neph1 homolog Roughest (Rst), an immunoglobulin family cell surface adhesion molecule expressed in interommatidial cells (IOCs). Here, using a novel temperature-sensitive (ts) allele, we show that the phosphoinositide phosphatase Sac1 is also required for IOC patterning. Sac1ts mutants have rough eyes and retinal patterning defects that resemble rst mutants. Sac1ts retinas exhibit elevated levels of phosphatidylinositol 4-phosphate (PI4P), consistent with the role of Sac1 as a PI4P phosphatase. Indeed, genetic rescue and interaction experiments reveal that restriction of PI4P levels by Sac1 is crucial for normal eye development. Rst is delivered to the cell surface in Sac1ts mutants. However, Sac1ts mutant IOCs exhibit severe defects in microtubule organization, associated with accumulation of Rst and the exocyst subunit Sec8 in enlarged intracellular vesicles upon cold fixation ex vivo Together, our data reveal a novel requirement for Sac1 in promoting microtubule stability and suggest that Rst trafficking occurs in a microtubule- and exocyst-dependent manner.
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Affiliation(s)
- Lauren M Del Bel
- Cell Biology Program, The Hospital for Sick Children, PGCRL Building, 686 Bay Street, Toronto, Ontario, M5G 0A4, Canada
- Department of Molecular Genetics, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada
| | - Nigel Griffiths
- Cell Biology Program, The Hospital for Sick Children, PGCRL Building, 686 Bay Street, Toronto, Ontario, M5G 0A4, Canada
- Department of Molecular Genetics, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada
| | - Ronit Wilk
- Cell Biology Program, The Hospital for Sick Children, PGCRL Building, 686 Bay Street, Toronto, Ontario, M5G 0A4, Canada
| | - Ho-Chun Wei
- Cell Biology Program, The Hospital for Sick Children, PGCRL Building, 686 Bay Street, Toronto, Ontario, M5G 0A4, Canada
- Department of Molecular Biology and Biochemistry, Simon Fraser University, South Sciences Building Room 8166, 8888 University Drive, Burnaby, British Columbia, V5A 1S6, Canada
| | - Anastasia Blagoveshchenskaya
- Division of Nephrology & Hypertension, Oregon Health & Science University, 3181 S.W. Sam Jackson Park Rd., Portland, Oregon 97239-3098, USA
| | - Jason Burgess
- Cell Biology Program, The Hospital for Sick Children, PGCRL Building, 686 Bay Street, Toronto, Ontario, M5G 0A4, Canada
- Department of Molecular Genetics, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada
| | - Gordon Polevoy
- Cell Biology Program, The Hospital for Sick Children, PGCRL Building, 686 Bay Street, Toronto, Ontario, M5G 0A4, Canada
| | - James V Price
- Department of Molecular Biology and Biochemistry, Simon Fraser University, South Sciences Building Room 8166, 8888 University Drive, Burnaby, British Columbia, V5A 1S6, Canada
| | - Peter Mayinger
- Division of Nephrology & Hypertension, Oregon Health & Science University, 3181 S.W. Sam Jackson Park Rd., Portland, Oregon 97239-3098, USA
| | - Julie A Brill
- Cell Biology Program, The Hospital for Sick Children, PGCRL Building, 686 Bay Street, Toronto, Ontario, M5G 0A4, Canada
- Department of Molecular Genetics, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada
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Bala Tannan N, Collu G, Humphries AC, Serysheva E, Weber U, Mlodzik M. AKAP200 promotes Notch stability by protecting it from Cbl/lysosome-mediated degradation in Drosophila melanogaster. PLoS Genet 2018; 14:e1007153. [PMID: 29309414 PMCID: PMC5785023 DOI: 10.1371/journal.pgen.1007153] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 01/25/2018] [Accepted: 12/13/2017] [Indexed: 12/30/2022] Open
Abstract
AKAP200 is a Drosophila melanogaster member of the “A Kinase Associated Protein” family of scaffolding proteins, known for their role in the spatial and temporal regulation of Protein Kinase A (PKA) in multiple signaling contexts. Here, we demonstrate an unexpected function of AKAP200 in promoting Notch protein stability. In Drosophila, AKAP200 loss-of-function (LOF) mutants show phenotypes that resemble Notch LOF defects, including eye patterning and sensory organ specification defects. Through genetic interactions, we demonstrate that AKAP200 interacts positively with Notch in both the eye and the thorax. We further show that AKAP200 is part of a physical complex with Notch. Biochemical studies reveal that AKAP200 stabilizes endogenous Notch protein, and that it limits ubiquitination of Notch. Specifically, our genetic and biochemical evidence indicates that AKAP200 protects Notch from the E3-ubiquitin ligase Cbl, which targets Notch to the lysosomal pathway. Indeed, we demonstrate that the effect of AKAP200 on Notch levels depends on the lysosome. Interestingly, this function of AKAP200 is fully independent of its role in PKA signaling and independent of its ability to bind PKA. Taken together, our data indicate that AKAP200 is a novel tissue specific posttranslational regulator of Notch, maintaining high Notch protein levels and thus promoting Notch signaling. AKAP200 belongs to a family of scaffolding proteins best known for their regulation of PKA localization. In this study, we have identified a novel role of AKAP200 in Notch protein stability and signaling. In Drosophila melanogaster, AKAP200’s loss and gain-of-function (LOF/GOF) phenotypes are characteristic of Notch signaling defects. Furthermore, we demonstrated genetic interactions between AKAP200 and Notch. Consistent with this, AKAP200 stabilizes the endogenous Notch protein and limits its ubiquitination. AKAP200 exerts its effects on Notch by antagonizing Cbl-mediated ubiquitination and thus lysosome targeting of Notch. Based on these data, we postulate a novel PKA independent mechanism of AKAP200 to achieve optimal Notch protein levels, with AKAP200 preventing Cbl-mediated lysosomal degradation of Notch.
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Affiliation(s)
- Neeta Bala Tannan
- Dept. of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Giovanna Collu
- Dept. of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Ashley C. Humphries
- Dept. of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Ekatherina Serysheva
- Dept. of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Ursula Weber
- Dept. of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Marek Mlodzik
- Dept. of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
- Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
- * E-mail:
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49
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Pandey A, Jafar-Nejad H. Cell Aggregation Assays to Evaluate the Binding of the Drosophila Notch with Trans-Ligands and its Inhibition by Cis-Ligands. J Vis Exp 2018. [PMID: 29364239 DOI: 10.3791/56919] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Notch signaling is an evolutionarily conserved cell-cell communication system used broadly in animal development and adult maintenance. Interaction of the Notch receptor with ligands from neighboring cells induces activation of the signaling pathway (trans-activation), while interaction with ligands from the same cell inhibits signaling (cis-inhibition). Proper balance between trans-activation and cis-inhibition helps establish optimal levels of Notch signaling in some contexts during animal development. Because of the overlapping expression domains of Notch and its ligands in many cell types and the existence of feedback mechanisms, studying the effects of a given post-translational modification on trans- versus cis-interactions of Notch and its ligands in vivo is difficult. Here, we describe a protocol for using Drosophila S2 cells in cell-aggregation assays to assess the effects of knocking down a Notch pathway modifier on the binding of Notch to each ligand in trans and in cis. S2 cells stably or transiently transfected with a Notch-expressing vector are mixed with cells expressing each Notch ligand (S2-Delta or S2-Serrate). Trans-binding between the receptor and ligands results in the formation of heterotypic cell aggregates and is measured in terms of the number of aggregates per mL composed of >6 cells. To examine the inhibitory effect of cis-ligands, S2 cells co-expressing Notch and each ligand are mixed with S2-Delta or S2-Serrate cells and the number of aggregates is quantified as described above. The relative decrease in the number of aggregates due to the presence of cis-ligands provides a measure of cis-ligand-mediated inhibition of trans-binding. These straightforward assays can provide semi-quantitative data on the effects of genetic or pharmacological manipulations on the binding of Notch to its ligands, and can help deciphering the molecular mechanisms underlying the in vivo effects of such manipulations on Notch signaling.
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Affiliation(s)
- Ashutosh Pandey
- Department of Molecular and Human Genetics, Baylor College of Medicine
| | - Hamed Jafar-Nejad
- Department of Molecular and Human Genetics, Baylor College of Medicine; Program in Developmental Biology, Baylor College of Medicine;
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50
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Harvey BM, Haltiwanger RS. Regulation of Notch Function by O-Glycosylation. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1066:59-78. [PMID: 30030822 DOI: 10.1007/978-3-319-89512-3_4] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The Notch receptor initiates a unique intercellular signaling pathway that is evolutionarily conserved across all metazoans and contributes to the development and maintenance of numerous tissues. Consequently, many diseases result from aberrant Notch signaling. Emerging roles for Notch in disease are being uncovered as studies reveal new information regarding various components of this signaling pathway. Notch activity is regulated at several levels, but O-linked glycosylation of Epidermal Growth Factor (EGF) repeats in the Notch extracellular domain has emerged as a major regulator that, depending on context, can increase or decrease Notch activity. Three types of O-linked glycosylation occur at consensus sequences found within the EGF repeats of Notch: O-fucosylation, O-glucosylation, and O-GlcNAcylation. Recent studies have investigated the site occupancy of these types of glycosylation and also defined specific roles for these glycans on Notch structure and function. Nevertheless, there are many functional aspects to each type of O-glycosylation that remain unclear. Here, we will discuss molecular mechanisms of how O-glycosylation regulates Notch signaling and describe disorders associated with defects in Notch O-glycosylation.
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Affiliation(s)
- Beth M Harvey
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY, USA.,Present Address: Department of Cell and Developmental Biology, University of Pennsylvania, Philadelphia, PA, USA
| | - Robert S Haltiwanger
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY, USA. .,Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA.
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