1
|
Kulkarni PP, Ekhlak M, Dash D. Non-canonical non-genomic morphogen signaling in anucleate platelets: a critical determinant of prothrombotic function in circulation. Cell Commun Signal 2024; 22:13. [PMID: 38172855 PMCID: PMC10763172 DOI: 10.1186/s12964-023-01448-y] [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: 11/08/2023] [Accepted: 12/19/2023] [Indexed: 01/05/2024] Open
Abstract
Circulating platelets derived from bone marrow megakaryocytes play a central role in thrombosis and hemostasis. Despite being anucleate, platelets express several proteins known to have nuclear niche. These include transcription factors and steroid receptors whose non-genomic functions are being elucidated in platelets. Quite remarkably, components of some of the best-studied morphogen pathways, namely Notch, Sonic Hedgehog (Shh), and Wnt have also been described in recent years in platelets, which regulate platelet function in the context of thrombosis as well as influence their survival. Shh and Notch pathways in stimulated platelets establish feed-forward loops of autocrine/juxtacrine/paracrine non-canonical signaling that helps perpetuate thrombosis. On the other hand, non-canonical Wnt signaling is part of a negative feedback loop for restricting platelet activation and possibly limiting thrombus growth. The present review will provide an overview of these signaling pathways in general. We will then briefly discuss the non-genomic roles of transcription factors and steroid receptors in platelet activation. This will be followed by an elaborate description of morphogen signaling in platelets with a focus on their bearing on platelet activation leading to hemostasis and thrombosis as well as their potential for therapeutic targeting in thrombotic disorders.
Collapse
Affiliation(s)
- Paresh P Kulkarni
- Center for Advanced Research on Platelet Signaling and Thrombosis Biology, Department of Biochemistry, Institute of Medical Sciences, Banaras Hindu University, Varanasi, 221005, Uttar Pradesh, India.
| | - Mohammad Ekhlak
- Center for Advanced Research on Platelet Signaling and Thrombosis Biology, Department of Biochemistry, Institute of Medical Sciences, Banaras Hindu University, Varanasi, 221005, Uttar Pradesh, India
| | - Debabrata Dash
- Center for Advanced Research on Platelet Signaling and Thrombosis Biology, Department of Biochemistry, Institute of Medical Sciences, Banaras Hindu University, Varanasi, 221005, Uttar Pradesh, India.
| |
Collapse
|
2
|
Zhao X, Guo S. Antibody Uptake Assay for Tracking Notch/Delta Endocytosis During the Asymmetric Division of Zebrafish Radial Glia Progenitors. J Vis Exp 2023:10.3791/65030. [PMID: 36744775 PMCID: PMC11068441 DOI: 10.3791/65030] [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] [Indexed: 01/22/2023] Open
Abstract
Asymmetric cell division (ACD), which produces two daughter cells of different fates, is fundamental for generating cellular diversity. In the developing organs of both invertebrates and vertebrates, asymmetrically dividing progenitors generates a Notchhi self-renewing and a Notchlo differentiating daughter. In the embryonic zebrafish brain, radial glia progenitors (RGPs)-the principal vertebrate neural stem cells-mostly undergo ACD to give birth to one RGP and one differentiating neuron. The optical clarity and easy accessibility of zebrafish embryos make them ideal for in vivo time-lapse imaging to directly visualize how and when the asymmetry of Notch signaling is established during ACD. Recent studies have shown that dynamic endocytosis of the Notch ligand DeltaD plays a crucial role in cell fate determination during ACD, and the process is regulated by the evolutionarily conserved polarity regulator Par-3 (also known as Pard3) and the dynein motor complex. To visualize the in vivo trafficking patterns of Notch signaling endosomes in mitotic RGPs, we have developed this antibody uptake assay. Using the assay, we have uncovered the dynamicity of DeltaD-containing endosomes during RGP division.
Collapse
Affiliation(s)
- Xiang Zhao
- Chan Zuckerberg Biohub; Department of Bioengineering and Therapeutic Sciences, University of California San Francisco;
| | - Su Guo
- Department of Bioengineering and Therapeutic Sciences, University of California San Francisco; Programs in Human Genetics and Biological Sciences, University of California San Francisco;
| |
Collapse
|
3
|
Vázquez-Ulloa E, Lin KL, Lizano M, Sahlgren C. Reversible and bidirectional signaling of notch ligands. Crit Rev Biochem Mol Biol 2022; 57:377-398. [PMID: 36048510 DOI: 10.1080/10409238.2022.2113029] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The Notch signaling pathway is a direct cell-cell communication system involved in a wide variety of biological processes, and its disruption is observed in several pathologies. The pathway is comprised of a ligand-expressing (sender) cell and a receptor-expressing (receiver) cell. The canonical ligands are members of the Delta/Serrate/Lag-1 (DSL) family of proteins. Their binding to a Notch receptor in a neighboring cell induces a conformational change in the receptor, which will undergo regulated intramembrane proteolysis (RIP), liberating the Notch intracellular domain (NICD). The NICD is translocated to the nucleus and promotes gene transcription. It has been demonstrated that the ligands can also undergo RIP and nuclear translocation, suggesting a function for the ligands in the sender cell and possible bidirectionality of the Notch pathway. Although the complete mechanism of ligand processing is not entirely understood, and its dependence on Notch receptors has not been ruled out. Also, ligands have autonomous functions beyond Notch activation. Here we review the concepts of reverse and bidirectional signalization of DSL proteins and discuss the characteristics that make them more than just ligands of the Notch pathway.
Collapse
Affiliation(s)
- Elenaé Vázquez-Ulloa
- Faculty of Science and Engineering/Cell Biology, Åbo Akademi University, Turku, Finland.,Turku Bioscience, University of Turku and Åbo Akademi University, Turku, Finland
| | - Kai-Lan Lin
- Faculty of Science and Engineering/Cell Biology, Åbo Akademi University, Turku, Finland.,Turku Bioscience, University of Turku and Åbo Akademi University, Turku, Finland
| | - Marcela Lizano
- Unidad de Investigación Biomédica en Cáncer, Instituto Nacional de Cancerología- Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Mexico City, Mexico.,Departamento de Medicina Genomica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad Universitaria, Mexico City, Mexico
| | - Cecilia Sahlgren
- Faculty of Science and Engineering/Cell Biology, Åbo Akademi University, Turku, Finland.,Turku Bioscience, University of Turku and Åbo Akademi University, Turku, Finland.,Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands.,Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, The Netherlands
| |
Collapse
|
4
|
Francis CR, Kushner EJ. Trafficking in blood vessel development. Angiogenesis 2022; 25:291-305. [PMID: 35449244 PMCID: PMC9249721 DOI: 10.1007/s10456-022-09838-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Accepted: 04/03/2022] [Indexed: 02/17/2023]
Abstract
Blood vessels demonstrate a multitude of complex signaling programs that work in concert to produce functional vasculature networks during development. A known, but less widely studied, area of endothelial cell regulation is vesicular trafficking, also termed sorting. After moving through the Golgi apparatus, proteins are shuttled to organelles, plugged into membranes, recycled, or degraded depending on the internal and extrinsic cues. A snapshot of these protein-sorting systems can be viewed as a trafficking signature that is not only unique to endothelial tissue, but critically important for blood vessel form and function. In this review, we will cover how vesicular trafficking impacts various aspects of angiogenesis, such as sprouting, lumen formation, vessel stabilization, and secretion, emphasizing the role of Rab GTPase family members and their various effectors.
Collapse
Affiliation(s)
- Caitlin R Francis
- Department of Biological Sciences, University of Denver, Denver, CO, 80210, USA
| | - Erich J Kushner
- Department of Biological Sciences, University of Denver, Denver, CO, 80210, USA.
| |
Collapse
|
5
|
Zhao X, Garcia J, Royer LA, Guo S. Colocalization Analysis for Cryosectioned and Immunostained Tissue Samples with or without Label Retention Expansion Microscopy (LR-ExM) by JACoP. Bio Protoc 2022; 12:e4336. [PMID: 35592606 PMCID: PMC8918214 DOI: 10.21769/bioprotoc.4336] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Revised: 10/25/2021] [Accepted: 01/10/2022] [Indexed: 12/29/2022] Open
Abstract
Asymmetric cell division (ACD) is fundamental for balancing cell proliferation and differentiation in metazoans. During active neurogenesis in the developing zebrafish forebrain, radial glia progenitors (RGPs) mainly undergo ACD to produce one daughter with high activity of Delta/Notch signaling (proliferative cell fate) and another daughter with low Delta/Notch signaling (differentiative cell fate). The cell polarity protein partitioning-defective 3 (Par-3) is critical for regulating this process. To understand how polarized Par-3 on the cell cortex can lead to differential Notch activity in the nuclei of daughter cells, we combined an anti-Delta D (Dld) -atto 647N antibody uptake assay with label retention expansion microscopy (LR-ExM), to obtain high resolution immunofluorescent images of Par-3, dynein light intermediate chain 1 (Dlic1), and Dld endosomes in mitotic RGPs. We then developed a protocol for analyzing the colocalization of Par-3, Dlic1, and endosomal DeltaD, using JACoP (Just Another Co-localization Plugin) in ImageJ software (Bolte and Cordelières, 2006). Through such analyses, we have shown that cytosolic Par-3 is associated with Dlic1 on Dld endosomes. Our work demonstrates a direct involvement of Par-3 in dynein-mediated polarized transport of Notch signaling endosomes. This bio-protocol may be generalizable for analysis of protein co-localization in any cryosectioned and immunostained tissue samples.
Collapse
Affiliation(s)
- Xiang Zhao
- Chan Zuckerberg Biohub, San Francisco, USA.,Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, USA
| | - Jason Garcia
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, USA.,Tetrad Graduate Program, University of California, San Francisco, San Francisco, CA 94143, USA
| | | | - Su Guo
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, USA.,Tetrad Graduate Program, University of California, San Francisco, San Francisco, CA 94143, USA.,Programs in Human Genetics and Biological Sciences, University of California, San Francisco, San Francisco, CA 94143, USA
| |
Collapse
|
6
|
Saraswathy VM, Kurup AJ, Sharma P, Polès S, Poulain M, Fürthauer M. The E3 Ubiquitin Ligase Mindbomb1 controls planar cell polarity-dependent convergent extension movements during zebrafish gastrulation. eLife 2022; 11:71928. [PMID: 35142609 PMCID: PMC8937233 DOI: 10.7554/elife.71928] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 02/09/2022] [Indexed: 11/13/2022] Open
Abstract
Vertebrate Delta/Notch signaling involves multiple ligands, receptors and transcription factors. Delta endocytosis - a critical event for Notch activation - is however essentially controlled by the E3 Ubiquitin ligase Mindbomb1 (Mib1). Mib1 inactivation is therefore often used to inhibit Notch signaling. However, recent findings indicate that Mib1 function extends beyond the Notch pathway. We report a novel Notch-independent role of Mib1 in zebrafish gastrulation. mib1 null mutants and morphants display impaired Convergence Extension (CE) movements. Comparison of different mib1 mutants and functional rescue experiments indicate that Mib1 controls CE independently of Notch. Mib1-dependent CE defects can be rescued using the Planar Cell Polarity (PCP) downstream mediator RhoA, or enhanced through knock-down of the PCP ligand Wnt5b. Mib1 regulates CE through its RING Finger domains that have been implicated in substrate ubiquitination, suggesting that Mib1 may control PCP protein trafficking. Accordingly, we show that Mib1 controls the endocytosis of the PCP component Ryk and that Ryk internalization is required for CE. Numerous morphogenetic processes involve both Notch and PCP signaling. Our observation that during zebrafish gastrulation Mib1 exerts a Notch-independent control of PCP-dependent CE movements suggest that Mib1 loss of function phenotypes should be cautiously interpreted depending on the biological context.
Collapse
Affiliation(s)
| | | | | | - Sophie Polès
- Université Côte d'Azur, CNRS, Inserm, iBV, Nice, France
| | | | | |
Collapse
|
7
|
Esteves de Lima J, Blavet C, Bonnin MA, Hirsinger E, Havis E, Relaix F, Duprez D. TMEM8C-mediated fusion is regionalized and regulated by NOTCH signalling during foetal myogenesis. Development 2022; 149:274065. [PMID: 35005776 DOI: 10.1242/dev.199928] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Accepted: 12/15/2021] [Indexed: 12/30/2022]
Abstract
The location and regulation of fusion events within skeletal muscles during development remain unknown. Using the fusion marker myomaker (Mymk), named TMEM8C in chicken, as a readout of fusion, we identified a co-segregation of TMEM8C-positive cells and MYOG-positive cells in single-cell RNA-sequencing datasets of limbs from chicken embryos. We found that TMEM8C transcripts, MYOG transcripts and the fusion-competent MYOG-positive cells were preferentially regionalized in central regions of foetal muscles. We also identified a similar regionalization for the gene encoding the NOTCH ligand JAG2 along with an absence of NOTCH activity in TMEM8C+ fusion-competent myocytes. NOTCH function in myoblast fusion had not been addressed so far. We analysed the consequences of NOTCH inhibition for TMEM8C expression and myoblast fusion during foetal myogenesis in chicken embryos. NOTCH inhibition increased myoblast fusion and TMEM8C expression and released the transcriptional repressor HEYL from the TMEM8C regulatory regions. These results identify a regionalization of TMEM8C-dependent fusion and a molecular mechanism underlying the fusion-inhibiting effect of NOTCH in foetal myogenesis. The modulation of NOTCH activity in the fusion zone could regulate the flux of fusion events.
Collapse
Affiliation(s)
- Joana Esteves de Lima
- Sorbonne Université, Institut Biologie Paris Seine, CNRS UMR7622, Developmental Biology Laboratory, Inserm U1156, F-75005 Paris, France.,Univ Paris Est Creteil, INSERM, EnvA, EFS, AP-HP, IMRB, F-94010 Creteil, France
| | - Cédrine Blavet
- Sorbonne Université, Institut Biologie Paris Seine, CNRS UMR7622, Developmental Biology Laboratory, Inserm U1156, F-75005 Paris, France
| | - Marie-Ange Bonnin
- Sorbonne Université, Institut Biologie Paris Seine, CNRS UMR7622, Developmental Biology Laboratory, Inserm U1156, F-75005 Paris, France
| | - Estelle Hirsinger
- Sorbonne Université, Institut Biologie Paris Seine, CNRS UMR7622, Developmental Biology Laboratory, Inserm U1156, F-75005 Paris, France
| | - Emmanuelle Havis
- Sorbonne Université, Institut Biologie Paris Seine, CNRS UMR7622, Developmental Biology Laboratory, Inserm U1156, F-75005 Paris, France
| | - Frédéric Relaix
- Univ Paris Est Creteil, INSERM, EnvA, EFS, AP-HP, IMRB, F-94010 Creteil, France
| | - Delphine Duprez
- Sorbonne Université, Institut Biologie Paris Seine, CNRS UMR7622, Developmental Biology Laboratory, Inserm U1156, F-75005 Paris, France
| |
Collapse
|
8
|
Bermick JR, Lincoln PM, Allen RM, Kunkel SL, Schaller MA. Elevated Notch ligands in serum are associated with HIV/TB coinfection. J Clin Tuberc Other Mycobact Dis 2021; 24:100258. [PMID: 34307905 PMCID: PMC8258674 DOI: 10.1016/j.jctube.2021.100258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Objective There is a clear need for improved biomarkers to diagnose HIV/TB coinfection. Although numerous tests can identify the existence of both of these microbes within the host, a parallel assessment of the host response to HIV/TB coinfection may prove as useful confirmation in cases where microbiological tests are inconclusive. To this end we assessed the levels of Notch ligands found in serum samples of patients with TB, HIV or HIV/TB coinfection. The Notch system is involved in almost every stage of development, including the maturation of the immune response. Upon exposure to a pathogen, the innate immune system will increase expression of Notch ligands Delta-like 1 and Delta-like 4. Previous research has demonstrated that Notch ligand expression is increased on monocytes from patients diagnosed with tuberculosis. We hypothesized that if Notch ligands were present in the peripheral blood of individuals diagnosed with TB, they may serve as a novel marker for infection. Design: Serum samples from patients with HIV, TB or HIV/TB coinfection were compared to serum from uninfected individuals to determine levels of DLL1 and DLL4 in a case controlled study. Methods DLL1 and DLL4 were measured by ELISA. Linear regression with post tests were used to determine if levels of DLL1 and DLL4 were increased in individuals with HIV/TB coinfection as compared to individuals infected with either HIV or TB or healthy controls. Results Delta-like 1 and Delta-like 4 were significantly increased in the serum of patients with HIV and HIV/ M. tuberculosis coinfection compared to other groups. Conclusions Assessment of Notch ligands in peripheral blood may enhance the diagnosis of individuals with active TB that are co-infected with HIV. The study will also need to be validated in in a larger cohort.
Collapse
Affiliation(s)
- Jennifer R Bermick
- Department of Pediatrics, Division of Neonatology, University of Iowa, Iowa City, IA, USA.,Department of Pediatrics, University of Michigan, Ann Arbor, MI, USA
| | - Pamela M Lincoln
- Department of Pathology, University of Michigan, Ann Arbor, MI, USA
| | - Ronald M Allen
- Department of Pathology, University of Michigan, Ann Arbor, MI, USA
| | - Steven L Kunkel
- Department of Pathology, University of Michigan, Ann Arbor, MI, USA
| | - Matthew A Schaller
- Department of Pathology, University of Michigan, Ann Arbor, MI, USA.,Division of Pulmonary, Critical Care and Sleep Medicine, University of Florida, Gainesville, FL, USA
| |
Collapse
|
9
|
York HM, Coyle J, Arumugam S. To be more precise: the role of intracellular trafficking in development and pattern formation. Biochem Soc Trans 2020; 48:2051-2066. [PMID: 32915197 PMCID: PMC7609031 DOI: 10.1042/bst20200223] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 08/24/2020] [Accepted: 08/26/2020] [Indexed: 02/07/2023]
Abstract
Living cells interpret a variety of signals in different contexts to elucidate functional responses. While the understanding of signalling molecules, their respective receptors and response at the gene transcription level have been relatively well-explored, how exactly does a single cell interpret a plethora of time-varying signals? Furthermore, how their subsequent responses at the single cell level manifest in the larger context of a developing tissue is unknown. At the same time, the biophysics and chemistry of how receptors are trafficked through the complex dynamic transport network between the plasma membrane-endosome-lysosome-Golgi-endoplasmic reticulum are much more well-studied. How the intracellular organisation of the cell and inter-organellar contacts aid in orchestrating trafficking, as well as signal interpretation and modulation by the cells are beginning to be uncovered. In this review, we highlight the significant developments that have strived to integrate endosomal trafficking, signal interpretation in the context of developmental biology and relevant open questions with a few chosen examples. Furthermore, we will discuss the imaging technologies that have been developed in the recent past that have the potential to tremendously accelerate knowledge gain in this direction while shedding light on some of the many challenges.
Collapse
Affiliation(s)
- Harrison M. York
- Monash Biomedicine Discovery Institute, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, VIC 3800, Australia
| | - Joanne Coyle
- Monash Biomedicine Discovery Institute, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, VIC 3800, Australia
| | - Senthil Arumugam
- Monash Biomedicine Discovery Institute, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, VIC 3800, Australia
- European Molecular Biological Laboratory Australia (EMBL Australia), Monash University, Melbourne, VIC 3800, Australia
- ARC Centre of Excellence in Advanced Molecular Imaging, Monash University, Melbourne, VIC 3800, Australia
| |
Collapse
|
10
|
Scavuzzo MA, Chmielowiec J, Yang D, Wamble K, Chaboub LS, Duraine L, Tepe B, Glasgow SM, Arenkiel BR, Brou C, Deneen B, Borowiak M. Pancreatic Cell Fate Determination Relies on Notch Ligand Trafficking by NFIA. Cell Rep 2018; 25:3811-3827.e7. [PMID: 30590051 DOI: 10.1016/j.celrep.2018.11.078] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Revised: 09/28/2018] [Accepted: 11/20/2018] [Indexed: 12/24/2022] Open
Abstract
Notch is activated globally in pancreatic progenitors; however, for progenitors to differentiate into endocrine cells, they must escape Notch activation to express Neurogenin-3. Here, we find that the transcription factor nuclear factor I/A (NFIA) promotes endocrine development by regulating Notch ligand Dll1 trafficking. Pancreatic deletion of NFIA leads to cell fate defects, with increased duct and decreased endocrine formation, while ectopic expression promotes endocrine formation in mice and human pancreatic progenitors. NFIA-deficient mice exhibit dysregulation of trafficking-related genes including increased expression of Mib1, which acts to target Dll1 for endocytosis. We find that NFIA binds to the Mib1 promoter, with loss of NFIA leading to an increase in Dll1 internalization and enhanced Notch activation with rescue of the cell fate defects after Mib1 knockdown. This study reveals NFIA as a pro-endocrine factor in the pancreas, acting to repress Mib1, inhibit Dll1 endocytosis and thus promote escape from Notch activation.
Collapse
Affiliation(s)
- Marissa A Scavuzzo
- Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Jolanta Chmielowiec
- Center for Cell and Gene Therapy, Baylor College of Medicine, Texas Children's Hospital, and Houston Methodist Hospital, Houston, TX 77030, USA; Stem Cell and Regenerative Medicine Center, Baylor College of Medicine, Houston, TX 77030, USA
| | - Diane Yang
- Molecular and Cellular Biology Department, Baylor College of Medicine, Houston, TX 77030, USA
| | - Katrina Wamble
- Center for Cell and Gene Therapy, Baylor College of Medicine, Texas Children's Hospital, and Houston Methodist Hospital, Houston, TX 77030, USA; Stem Cell and Regenerative Medicine Center, Baylor College of Medicine, Houston, TX 77030, USA
| | - Lesley S Chaboub
- Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Lita Duraine
- Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX 77030, USA
| | - Burak Tepe
- Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Stacey M Glasgow
- Center for Cell and Gene Therapy, Baylor College of Medicine, Texas Children's Hospital, and Houston Methodist Hospital, Houston, TX 77030, USA; Stem Cell and Regenerative Medicine Center, Baylor College of Medicine, Houston, TX 77030, USA; Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | - Benjamin R Arenkiel
- Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030, USA; Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA; McNair Medical Institute, Baylor College of Medicine, Houston, TX 77030, USA; Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Christel Brou
- Department of Cell Biology and Infection, Institute Pasteur, 25 rue du Docteur Roux, 75724 Paris Cedex 15, France
| | - Benjamin Deneen
- Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030, USA; Center for Cell and Gene Therapy, Baylor College of Medicine, Texas Children's Hospital, and Houston Methodist Hospital, Houston, TX 77030, USA; Stem Cell and Regenerative Medicine Center, Baylor College of Medicine, Houston, TX 77030, USA; Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | - Malgorzata Borowiak
- Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030, USA; Center for Cell and Gene Therapy, Baylor College of Medicine, Texas Children's Hospital, and Houston Methodist Hospital, Houston, TX 77030, USA; Stem Cell and Regenerative Medicine Center, Baylor College of Medicine, Houston, TX 77030, USA; Molecular and Cellular Biology Department, Baylor College of Medicine, Houston, TX 77030, USA; Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA; McNair Medical Institute, Baylor College of Medicine, Houston, TX 77030, USA.
| |
Collapse
|
11
|
Nandagopal N, Santat LA, LeBon L, Sprinzak D, Bronner ME, Elowitz MB. Dynamic Ligand Discrimination in the Notch Signaling Pathway. Cell 2018; 172:869-880.e19. [PMID: 29398116 PMCID: PMC6414217 DOI: 10.1016/j.cell.2018.01.002] [Citation(s) in RCA: 200] [Impact Index Per Article: 33.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Revised: 08/10/2017] [Accepted: 01/03/2018] [Indexed: 01/08/2023]
Abstract
The Notch signaling pathway comprises multiple ligands that are used in distinct biological contexts. In principle, different ligands could activate distinct target programs in signal-receiving cells, but it is unclear how such ligand discrimination could occur. Here, we show that cells use dynamics to discriminate signaling by the ligands Dll1 and Dll4 through the Notch1 receptor. Quantitative single-cell imaging revealed that Dll1 activates Notch1 in discrete, frequency-modulated pulses that specifically upregulate the Notch target gene Hes1. By contrast, Dll4 activates Notch1 in a sustained, amplitude-modulated manner that predominantly upregulates Hey1 and HeyL. Ectopic expression of Dll1 or Dll4 in chick neural crest produced opposite effects on myogenic differentiation, showing that ligand discrimination can occur in vivo. Finally, analysis of chimeric ligands suggests that ligand-receptor clustering underlies dynamic encoding of ligand identity. The ability of the pathway to utilize ligands as distinct communication channels has implications for diverse Notch-dependent processes.
Collapse
Affiliation(s)
- Nagarajan Nandagopal
- Howard Hughes Medical Institute and Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Leah A Santat
- Howard Hughes Medical Institute and Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Lauren LeBon
- Calico Life Sciences, 1170 Veterans Boulevard, South San Francisco, CA 94080, USA
| | - David Sprinzak
- Department of Biochemistry and Molecular Biology, Wise Faculty of Life Sciences, Tel-Aviv University, Tel Aviv, Israel
| | - Marianne E Bronner
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Michael B Elowitz
- Howard Hughes Medical Institute, Division of Biology and Biological Engineering, Department of Applied Physics, California Institute of Technology, Pasadena, CA 91125, USA.
| |
Collapse
|
12
|
Endosomal Trafficking During Mitosis and Notch-Dependent Asymmetric Division. ENDOCYTOSIS AND SIGNALING 2018; 57:301-329. [DOI: 10.1007/978-3-319-96704-2_11] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
|
13
|
Abstract
Newly synthesized transmembrane proteins undergo a series of steps to ensure that only the required amount of correctly folded protein is localized to the membrane. The regulation of protein quality and its abundance at the membrane are often controlled by ubiquitination, a multistep enzymatic process that results in the attachment of ubiquitin, or chains of ubiquitin to the target protein. Protein ubiquitination acts as a signal for sorting, trafficking, and the removal of membrane proteins via endocytosis, a process through which multiple ubiquitin ligases are known to specifically regulate the functions of a number of ion channels, transporters, and signaling receptors. Endocytic removal of these proteins through ubiquitin-dependent endocytosis provides a way to rapidly downregulate the physiological outcomes, and defects in such controls are directly linked to human pathologies. Recent evidence suggests that ubiquitination is also involved in the shedding of membranes and associated proteins as extracellular vesicles, thereby not only controlling the cell surface levels of some membrane proteins, but also their potential transport to neighboring cells. In this review, we summarize the mechanisms and functions of ubiquitination of membrane proteins and provide specific examples of ubiquitin-dependent regulation of membrane proteins.
Collapse
Affiliation(s)
- Natalie Foot
- Centre for Cancer Biology, University of South Australia, Adelaide, Australia
| | - Tanya Henshall
- Centre for Cancer Biology, University of South Australia, Adelaide, Australia
| | - Sharad Kumar
- Centre for Cancer Biology, University of South Australia, Adelaide, Australia
| |
Collapse
|
14
|
Contreras-Cornejo H, Saucedo-Correa G, Oviedo-Boyso J, Valdez-Alarcón JJ, Baizabal-Aguirre VM, Cajero-Juárez M, Bravo-Patiño A. The CSL proteins, versatile transcription factors and context dependent corepressors of the notch signaling pathway. Cell Div 2016; 11:12. [PMID: 27708688 PMCID: PMC5037638 DOI: 10.1186/s13008-016-0025-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 09/16/2016] [Indexed: 12/24/2022] Open
Abstract
The Notch signaling pathway is a reiteratively used cell to cell communication pathway that triggers pleiotropic effects. The correct regulation of the pathway permits the efficient regulation of genes involved in cell fate decision throughout development. This activity relies notably on the CSL proteins, (an acronym for CBF-1/RBPJ-κ in Homo sapiens/Mus musculus respectively, Suppressor of Hairless in Drosophila melanogaster, Lag-1 in Caenorhabditis elegans) which is the unique transcription factor and DNA binding protein involved in this pathway. The CSL proteins have the capacity to recruit activation or repression complexes according to the cellular context. The aim of this review is to describe the different co-repressor proteins that interact directly with CSL proteins to form repression complexes thereby regulating the Notch signaling pathway in animal cells to give insights into the paralogous evolution of these co-repressors in higher eumetazoans and their subsequent effects at developmental processes.
Collapse
Affiliation(s)
- Humberto Contreras-Cornejo
- Centro Multidisciplinario de Estudios en Biotecnología (CMEB) de la Facultad de Medicina Veterinaria y Zootecnia, Universidad Michoacana de San Nicolás de Hidalgo, Posta Veterinaria, Km. 9.5 Carretera Morelia-Zinapécuaro, Col. La Palma, C. P. 58890 Tarímbaro, Mich. México
| | - Germán Saucedo-Correa
- Centro Multidisciplinario de Estudios en Biotecnología (CMEB) de la Facultad de Medicina Veterinaria y Zootecnia, Universidad Michoacana de San Nicolás de Hidalgo, Posta Veterinaria, Km. 9.5 Carretera Morelia-Zinapécuaro, Col. La Palma, C. P. 58890 Tarímbaro, Mich. México
| | - Javier Oviedo-Boyso
- Centro Multidisciplinario de Estudios en Biotecnología (CMEB) de la Facultad de Medicina Veterinaria y Zootecnia, Universidad Michoacana de San Nicolás de Hidalgo, Posta Veterinaria, Km. 9.5 Carretera Morelia-Zinapécuaro, Col. La Palma, C. P. 58890 Tarímbaro, Mich. México
| | - Juan José Valdez-Alarcón
- Centro Multidisciplinario de Estudios en Biotecnología (CMEB) de la Facultad de Medicina Veterinaria y Zootecnia, Universidad Michoacana de San Nicolás de Hidalgo, Posta Veterinaria, Km. 9.5 Carretera Morelia-Zinapécuaro, Col. La Palma, C. P. 58890 Tarímbaro, Mich. México
| | - Víctor Manuel Baizabal-Aguirre
- Centro Multidisciplinario de Estudios en Biotecnología (CMEB) de la Facultad de Medicina Veterinaria y Zootecnia, Universidad Michoacana de San Nicolás de Hidalgo, Posta Veterinaria, Km. 9.5 Carretera Morelia-Zinapécuaro, Col. La Palma, C. P. 58890 Tarímbaro, Mich. México
| | - Marcos Cajero-Juárez
- Instituto de Investigaciones Agropecuarias y Forestales (IIAF), Universidad Michoacana de San Nicolás de Hidalgo, Km. 9.5 Carretera Morelia-Zinapécuaro, Col. La Palma, C. P. 58890 Tarímbaro, Mich. México
| | - Alejandro Bravo-Patiño
- Centro Multidisciplinario de Estudios en Biotecnología (CMEB) de la Facultad de Medicina Veterinaria y Zootecnia, Universidad Michoacana de San Nicolás de Hidalgo, Posta Veterinaria, Km. 9.5 Carretera Morelia-Zinapécuaro, Col. La Palma, C. P. 58890 Tarímbaro, Mich. México
| |
Collapse
|
15
|
Esteves de Lima J, Bonnin MA, Birchmeier C, Duprez D. Muscle contraction is required to maintain the pool of muscle progenitors via YAP and NOTCH during fetal myogenesis. eLife 2016; 5. [PMID: 27554485 PMCID: PMC5030091 DOI: 10.7554/elife.15593] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Accepted: 08/23/2016] [Indexed: 12/27/2022] Open
Abstract
The importance of mechanical activity in the regulation of muscle progenitors during chick development has not been investigated. We show that immobilization decreases NOTCH activity and mimics a NOTCH loss-of-function phenotype, a reduction in the number of muscle progenitors and increased differentiation. Ligand-induced NOTCH activation prevents the reduction of muscle progenitors and the increase of differentiation upon immobilization. Inhibition of NOTCH ligand activity in muscle fibers suffices to reduce the progenitor pool. Furthermore, immobilization reduces the activity of the transcriptional co-activator YAP and the expression of the NOTCH ligand JAG2 in muscle fibers. YAP forced-activity in muscle fibers prevents the decrease of JAG2 expression and the number of PAX7+ cells in immobilization conditions. Our results identify a novel mechanism acting downstream of muscle contraction, where YAP activates JAG2 expression in muscle fibers, which in turn regulates the pool of fetal muscle progenitors via NOTCH in a non-cell-autonomous manner. DOI:http://dx.doi.org/10.7554/eLife.15593.001 Skeletal muscle is attached to the skeleton and allows the body to move. Making a new muscle, or repairing an existing one, relies on stem cells that are present inside muscles. A major goal of skeletal muscle research is to understand the signals that regulate the abilities of muscle stem cells to divide and give rise to more stem cells or to become muscle cells. Molecular signals are known to regulate the numbers of stem cells in the muscle. Skeletal muscles become larger if they are exercised, but it is not clear if mechanical forces generated by muscle contractions directly affect the number of muscle stem cells. The NOTCH signaling pathway contributes to maintaining the population of stem cells in muscles by forcing the stem cells to divide and preventing them from becoming muscle cells. Here, Esteves de Lima et al. investigated whether muscle contraction regulates NOTCH signaling during muscle formation in chick fetuses. The experiments show that muscle contraction stimulates the activity of a protein called YAP in muscle cells, which in turn, activates a gene in the NOTCH signaling pathway known as JAG2. This increases NOTCH signaling activity in the neighboring stem cells and maintains the number of stem cells in the muscle. The next step following this work will be to establish if this mechanism also operates during muscle formation and regeneration in other animals such as mice and zebrafish. DOI:http://dx.doi.org/10.7554/eLife.15593.002
Collapse
Affiliation(s)
- Joana Esteves de Lima
- CNRS UMR 7622, F-75005 Paris, France.,Sorbonne Universités, UPMC Univ Paris 06, Paris, France.,IBPS-Developmental Biology Laboratory, Paris, France.,Inserm U1156, F-75005, Paris, France
| | - Marie-Ange Bonnin
- CNRS UMR 7622, F-75005 Paris, France.,Sorbonne Universités, UPMC Univ Paris 06, Paris, France.,IBPS-Developmental Biology Laboratory, Paris, France.,Inserm U1156, F-75005, Paris, France
| | - Carmen Birchmeier
- Developmental Biology, Max-Delbrück-Center for Molecular Medicine, Berlin, Germany
| | - Delphine Duprez
- CNRS UMR 7622, F-75005 Paris, France.,Sorbonne Universités, UPMC Univ Paris 06, Paris, France.,IBPS-Developmental Biology Laboratory, Paris, France.,Inserm U1156, F-75005, Paris, France
| |
Collapse
|
16
|
Sturgeon M, Davis D, Albers A, Beatty D, Austin R, Ferguson M, Tounsel B, Liebl FLW. The Notch ligand E3 ligase, Mind Bomb1, regulates glutamate receptor localization in Drosophila. Mol Cell Neurosci 2015; 70:11-21. [PMID: 26596173 DOI: 10.1016/j.mcn.2015.11.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2015] [Revised: 11/09/2015] [Accepted: 11/16/2015] [Indexed: 12/29/2022] Open
Abstract
The postsynaptic density (PSD) is a protein-rich network important for the localization of postsynaptic glutamate receptors (GluRs) and for signaling downstream of these receptors. Although hundreds of PSD proteins have been identified, many are functionally uncharacterized. We conducted a reverse genetic screen for mutations that affected GluR localization using Drosophila genes that encode homologs of mammalian PSD proteins. 42.8% of the mutants analyzed exhibited a significant change in GluR localization at the third instar larval neuromuscular junction (NMJ), a model synapse that expresses homologs of AMPA receptors. We identified the E3 ubiquitin ligase, Mib1, which promotes Notch signaling, as a regulator of synaptic GluR localization. Mib1 positively regulates the localization of the GluR subunits GluRIIA, GluRIIB, and GluRIIC. Mutations in mib1 and ubiquitous expression of Mib1 that lacks its ubiquitin ligase activity result in the loss of synaptic GluRIIA-containing receptors. In contrast, overexpression of Mib1 in all tissues increases postsynaptic levels of GluRIIA. Cellular levels of Mib1 are also important for the structure of the presynaptic motor neuron. While deficient Mib1 signaling leads to overgrowth of the NMJ, ubiquitous overexpression of Mib1 results in a reduction in the number of presynaptic motor neuron boutons and branches. These synaptic changes may be secondary to attenuated glutamate release from the presynaptic motor neuron in mib1 mutants as mib1 mutants exhibit significant reductions in the vesicle-associated protein cysteine string protein and in the frequency of spontaneous neurotransmission.
Collapse
Affiliation(s)
- Morgan Sturgeon
- Department of Biological Sciences, Southern Illinois University Edwardsville, Edwardsville, IL 62026, United States
| | - Dustin Davis
- Department of Biological Sciences, Southern Illinois University Edwardsville, Edwardsville, IL 62026, United States
| | - Amanda Albers
- Department of Biological Sciences, Southern Illinois University Edwardsville, Edwardsville, IL 62026, United States
| | - Derek Beatty
- Department of Biological Sciences, Southern Illinois University Edwardsville, Edwardsville, IL 62026, United States
| | - Rik Austin
- Department of Biological Sciences, Southern Illinois University Edwardsville, Edwardsville, IL 62026, United States
| | - Matt Ferguson
- Department of Biological Sciences, Southern Illinois University Edwardsville, Edwardsville, IL 62026, United States
| | - Brittany Tounsel
- Department of Biological Sciences, Southern Illinois University Edwardsville, Edwardsville, IL 62026, United States
| | - Faith L W Liebl
- Department of Biological Sciences, Southern Illinois University Edwardsville, Edwardsville, IL 62026, United States.
| |
Collapse
|
17
|
Chou MH, Hsieh YC, Huang CW, Chen PH, Chan SP, Tsao YP, Lee HH, Wu JT, Chen SL. BCAS2 Regulates Delta-Notch Signaling Activity through Delta Pre-mRNA Splicing in Drosophila Wing Development. PLoS One 2015; 10:e0130706. [PMID: 26091239 PMCID: PMC4475048 DOI: 10.1371/journal.pone.0130706] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Accepted: 05/23/2015] [Indexed: 11/19/2022] Open
Abstract
Previously, we showed that BCAS2 is essential for Drosophila viability and functions in pre-mRNA splicing. In this study, we provide strong evidence that BCAS2 regulates the activity of Delta-Notch signaling via Delta pre-mRNA splicing. Depletion of dBCAS2 reduces Delta mRNA expression and leads to accumulation of Delta pre-mRNA, resulting in diminished transcriptions of Delta-Notch signaling target genes, such as cut and E(spl)m8. Furthermore, ectopic expression of human BCAS2 (hBCAS2) and Drosophila BCAS2 (dBCAS2) in a dBCAS2-deprived fly can rescue dBCAS2 depletion-induced wing damage to the normal phenotypes. These rescued phenotypes are correlated with the restoration of Delta pre-mRNA splicing, which affects Delta-Notch signaling activity. Additionally, overexpression of Delta can rescue the wing deformation by deprivation of dBCAS2; and the depletion of dBCAS2 can restore the aberrant eye associated with Delta-overexpressing retinas; providing supporting evidence for the regulation of Delta-Notch signaling by dBCAS2. Taken together, dBCAS2 participates in Delta pre-mRNA splicing that affects the regulation of Delta-Notch signaling in Drosophila wing development.
Collapse
Affiliation(s)
- Meng-Hsuan Chou
- Graduate Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, 100, Taiwan
| | - Yi-Chen Hsieh
- Graduate Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, 100, Taiwan
| | - Chu-Wei Huang
- Graduate Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, 100, Taiwan
| | - Po-Han Chen
- Graduate Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, 100, Taiwan
| | - Shih-Peng Chan
- Graduate Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, 100, Taiwan
| | - Yeou-Ping Tsao
- Department of Ophthalmology, Mackay Memorial Hospital, Taipei, 104, Taiwan
| | - Hsiu-Hsiang Lee
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, 100, Taiwan
| | - June-Tai Wu
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, 100, Taiwan
- Department of Medical Research, National Taiwan University Hospital, Taipei, 100, Taiwan
- * E-mail: (SLC); (JTW)
| | - Show-Li Chen
- Graduate Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, 100, Taiwan
- * E-mail: (SLC); (JTW)
| |
Collapse
|
18
|
Epidermal growth factor-like domain-containing protein 7 (EGFL7) enhances EGF receptor-AKT signaling, epithelial-mesenchymal transition, and metastasis of gastric cancer cells. PLoS One 2014; 9:e99922. [PMID: 24945379 PMCID: PMC4063792 DOI: 10.1371/journal.pone.0099922] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Accepted: 05/19/2014] [Indexed: 12/16/2022] Open
Abstract
Epidermal growth factor-like domain-containing protein 7 (EGFL7) is upregulated in human epithelial tumors and so is a potential biomarker for malignancy. Indeed, previous studies have shown that high EGFL7 expression promotes infiltration and metastasis of gastric carcinoma. The epithelial-mesenchymal transition (EMT) initiates the metastatic cascade and endows cancer cells with invasive and migratory capacity; however, it is not known if EGFL7 promotes metastasis by triggering EMT. We found that EGFL7 was overexpressed in multiple human gastric cancer (GC) cell lines and that overexpression promoted cell invasion and migration as revealed by scratch wound and transwell migration assays. Conversely, shRNA-mediated EGFL7 knockdown reduced invasion and migration. Furthermore, EGFL7-overexpressing cells grew into larger tumors and were more likely to metastasize to the liver compared to underexpressing CG cells following subcutaneous injection in mice. EGFL7 overexpression protected GC cell lines against anoikis, providing a plausible mechanism for this enhanced metastatic capacity. In excised human gastric tumors, expression of EGFL7 was positively correlated with expression levels of the mesenchymal marker vimentin and the EMT-associated transcription repressor Snail, and negatively correlated with expression of the epithelial cell marker E-cadherin. In GC cell lines, EGFL7 knockdown reversed morphological signs of EMT and decreased both vimentin and Snail expression. In addition, EGFL7 overexpression promoted EGF receptor (EGFR) and protein kinase B (AKT) phospho-activation, effects markedly suppressed by the EGFR tyrosine kinase inhibitor AG1478. Moreover, AG1478 also reduced the elevated invasive and migratory capacity of GC cell lines overexpressing EGFL7. Collectively, these results strongly suggest that EGFL7 promotes metastasis by activating EMT through an EGFR-AKT-Snail signaling pathway. Disruption of EGFL7-EGFR-AKT-Snail signaling may a promising therapeutic strategy for gastric cancer.
Collapse
|
19
|
Saritas-Yildirim B, Silva EM. The role of targeted protein degradation in early neural development. Genesis 2014; 52:287-99. [PMID: 24623518 DOI: 10.1002/dvg.22771] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Revised: 03/05/2014] [Accepted: 03/07/2014] [Indexed: 11/08/2022]
Abstract
As neural stem cells differentiate into neurons during neurogenesis, the proteome of the cells is restructured by de novo expression and selective removal of regulatory proteins. The control of neurogenesis at the level of gene regulation is well documented and the regulation of protein abundance through protein degradation via the Ubiquitin/26S proteasome pathway is a rapidly developing field. This review describes our current understanding of the role of the proteasome pathway in neurogenesis. Collectively, the studies show that targeted protein degradation is an important regulatory mechanism in the generation of new neurons.
Collapse
|
20
|
S/T phosphorylation of DLL1 is required for full ligand activity in vitro but dispensable for DLL1 function in vivo during embryonic patterning and marginal zone B cell development. Mol Cell Biol 2014; 34:1221-33. [PMID: 24449764 DOI: 10.1128/mcb.00965-13] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Interaction of Notch receptors with Delta- and Serrate-type ligands is an evolutionarily conserved mechanism that mediates direct communication between adjacent cells and thereby regulates multiple developmental processes. Posttranslational modifications of both receptors and ligands are pivotal for normal Notch pathway function. We have identified by mass spectrometric analysis two serine and one threonine phosphorylation sites in the intracellular domain of the mouse Notch ligand DLL1. Phosphorylation requires cell membrane association of DLL1 and occurs sequentially at the two serine residues. Phosphorylation of one serine residue most likely by protein kinase B primes phosphorylation of the other serine. A DLL1 variant, in which all three identified phosphorylated serine/threonine residues are mutated to alanine and valine, was more stable than wild-type DLL1 but had reduced relative levels on the cell surface and was more effectively cleaved in the extracellular domain. In addition, the mutant variant activated Notch1 significantly less efficient than wild-type DLL1 in a coculture assay in vitro. Mice, however, whose endogenous DLL1 was replaced with the phosphorylation-deficient triple mutant developed normally, suggesting compensatory mechanisms under physiological conditions in vivo.
Collapse
|
21
|
Heuss SF, Tarantino N, Fantini J, Ndiaye-Lobry D, Moretti J, Israël A, Logeat F. A glycosphingolipid binding domain controls trafficking and activity of the mammalian notch ligand delta-like 1. PLoS One 2013; 8:e74392. [PMID: 24069306 PMCID: PMC3771905 DOI: 10.1371/journal.pone.0074392] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Accepted: 08/01/2013] [Indexed: 01/12/2023] Open
Abstract
The activity of Notch ligands is tightly regulated by trafficking events occurring both before and after ligand-receptor interaction. In particular endocytosis and recycling have been shown to be required for full signaling activity of the ligands before they encounter the Notch receptor. However little is known about the precise endocytic processes that contribute to ligand internalization. Here we demonstrate that endocytosis contributes to Dll1 signaling activity by preserving the ligand from shedding and degradation. We further show that the glycosphingolipid-binding motif originally identified in Drosophila Notch ligands is conserved in mammals and is necessary for Dll1 internalization. Mutation of its conserved tryptophan residue results in a Dll1 molecule which is rapidly inactivated by shedding and degradation, does not recycle to the cell surface and does not activate Notch signaling. Finally, silencing in the signal-sending cells of glucosylceramide synthase, the enzyme implicated in the initial phase of glycosphingolipid synthesis, down-regulates Notch activation. Our data indicate that glycosphingolipids, by interacting with Dll1, may act as functional co-factors to promote its biological activity.
Collapse
Affiliation(s)
- Sara Farrah Heuss
- Unité de Signalisation Moléculaire et Activation Cellulaire, URA CNRS 2582, Institut Pasteur, Paris, France
| | | | | | | | | | | | | |
Collapse
|
22
|
Kang K, Lee D, Hong S, Park SG, Song MR. The E3 ligase Mind bomb-1 (Mib1) modulates Delta-Notch signaling to control neurogenesis and gliogenesis in the developing spinal cord. J Biol Chem 2012; 288:2580-92. [PMID: 23223237 DOI: 10.1074/jbc.m112.398263] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The Notch signaling pathway is essential for neuronal and glial specification during CNS development. Mind bomb-1 (Mib1) is an E3 ubiquitin ligase that ubiquitinates and promotes the endocytosis of Notch ligands. Although Mib1 is essential for transmitting the Notch signal, it is still unclear whether it is a primary regulator of Notch ligand activity in the developing spinal cord. In Mib1 conditional knock-out mice, we observed depletion of spinal progenitors, premature differentiation of neurons, and unbalanced specification of V2 interneurons, all of which mimic the conventional Notch phenotype. In agreement with this, the reduction of progenitors in the absence of Mib1 led to a loss of both astrocytes and oligodendrocytes. Late removal of Mib1 using a drug-inducible system suppressed glial differentiation, suggesting that Mib1 continues to play a role in the formation of late progenitors mainly designated for gliogenesis. Finally, misexpression of Mib1 or Mib1 deletion mutants revealed that the ring domain of Mib1 is required for the specification of V2 interneurons in the chick neural tube. Together, these findings suggest that Mib1 is a major component of the signal-sending cells required to provide Notch ligand activity for specifying neurons and glia in the spinal cord.
Collapse
Affiliation(s)
- Kyungjoon Kang
- School of Life Sciences, Bioimaging Research Center, Gwangju Institute of Science and Technology, Oryong-dong, Buk-gu, Gwangju 500-712, Republic of Korea
| | | | | | | | | |
Collapse
|
23
|
Barth JMI, Hafen E, Köhler K. The lack of autophagy triggers precocious activation of Notch signaling during Drosophila oogenesis. BMC DEVELOPMENTAL BIOLOGY 2012; 12:35. [PMID: 23217079 PMCID: PMC3564699 DOI: 10.1186/1471-213x-12-35] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/26/2012] [Accepted: 11/30/2012] [Indexed: 11/10/2022]
Abstract
BACKGROUND The proper balance of autophagy, a lysosome-mediated degradation process, is indispensable for oogenesis in Drosophila. We recently demonstrated that egg development depends on autophagy in the somatic follicle cells (FC), but not in the germline cells (GCs). However, the lack of autophagy only affects oogenesis when FCs are autophagy-deficient but GCs are wild type, indicating that a dysfunctional signaling between soma and germline may be responsible for the oogenesis defects. Thus, autophagy could play an essential role in modulating signal transduction pathways during egg development. RESULTS Here, we provide further evidence for the necessity of autophagy during oogenesis and demonstrate that autophagy is especially required in subsets of FCs. Generation of autophagy-deficient FCs leads to a wide range of phenotypes that are similar to mutants with defects in the classical cell-cell signaling pathways in the ovary. Interestingly, we observe that loss of autophagy leads to a precocious activation of the Notch pathway in the FCs as monitored by the expression of Cut and Hindsight, two downstream effectors of Notch signaling. CONCLUSION Our findings point to an unexpected function for autophagy in the modulation of the Notch signaling pathway during Drosophila oogenesis and suggest a function for autophagy in proper receptor activation. Egg development is affected by an imbalance of autophagy between signal sending (germline) and signal receiving cell (FC), thus the lack of autophagy in the germline is likely to decrease the amount of active ligand and accordingly compensates for increased signaling in autophagy-defective follicle cells.
Collapse
Affiliation(s)
- Julia M I Barth
- Institute of Molecular Systems Biology, ETH Zurich, Zurich, Switzerland
| | | | | |
Collapse
|
24
|
Notch and the p53 clan of transcription factors. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 727:223-40. [PMID: 22399351 DOI: 10.1007/978-1-4614-0899-4_17] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Notch 1 to 4 and the p53 clan, comprising p53, p63 and p73 plus numerous isoforms thereof, are gene transcription regulators that are critically involved in various aspects of cell differentiation, stem cell maintenance and tumour suppression. It is thus perhaps no surprise that extensive crosstalk between the Notch and p53 pathways is implemented during these processes. Typically, Notch together with p53 and even more so with transactivation competent p63 or p73, drives differentiation, whereas Notch combined with transactivation impaired p63 or p73 helps maintain undifferentiated stem cell compartments. With regard to cancer, it seems that Notch acts as a tumour suppressor in cellular contexts where Notch signalling supports p53 activation and both together can bring on its way an anti-proliferative programme of differentiation, senescence or apoptosis. In contrast, Notch often acts as an oncoprotein in contexts where it suppresses p53 activation and activity and where differentiation is unwanted. It is no accident that the latter pathways-the inhibition by Notch of p53 and differentiation-are operative in somatic stem cells as well as in tumour cells.
Collapse
|
25
|
Shah DK, Zúñiga-Pflücker JC. Notch receptor-ligand interactions during T cell development, a ligand endocytosis-driven mechanism. Curr Top Microbiol Immunol 2012; 360:19-46. [PMID: 22581027 DOI: 10.1007/82_2012_225] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Notch signaling plays an important role during the development of different cell types and tissues. The role of Notch signaling in lymphocyte development, in particular in the development and commitment to the T cell lineage, has been the focus of research for many years. Notch signaling is absolutely required during the commitment and early stages of T cell development. Activation of the Notch signaling pathway is initiated by ligand-receptor interactions and appears to require active endocytosis of Notch ligands. Studies addressing the mechanism underlying endocytosis of Notch ligands have helped to identify the main players important and necessary for this process. Here, we review the Notch ligands, and the proposed models of Notch activation by Notch ligand endocytosis, highlighting key molecules involved. In particular, we discuss recent studies on Notch ligands involved in T cell development, current studies aimed at elucidating the relevance of Notch ligand endocytosis during T cell development and the identification of key players necessary for ligand endocytosis in the thymus and during T cell development.
Collapse
Affiliation(s)
- Divya K Shah
- Department of Immunology, Sunnybrook Research Institute, University of Toronto, 2075 Bayview Avenue, Toronto, ON, M4 N 3M5, Canada.
| | | |
Collapse
|
26
|
Acosta H, López SL, Revinski DR, Carrasco AE. Notch destabilises maternal beta-catenin and restricts dorsal-anterior development in Xenopus. Development 2011; 138:2567-79. [PMID: 21610033 DOI: 10.1242/dev.061143] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The blastula chordin- and noggin-expressing centre (BCNE) is the predecessor of the Spemann-Mangold's organiser and also contains the precursors of the brain. This signalling centre comprises animal-dorsal and marginal-dorsal cells and appears as a consequence of the nuclear accumulation of β-catenin on the dorsal side. Here, we propose a role for Notch that was not previously explored during early development in vertebrates. Notch initially destabilises β-catenin in a process that does not depend on its phosphorylation by GSK3. This is important to restrict the BCNE to its normal extent and to control the size of the brain.
Collapse
Affiliation(s)
- Helena Acosta
- Laboratorio de Embriología Molecular, Instituto de Biología Celular y Neurociencias, Facultad de Medicina, Universidad de Buenos Aires, Paraguay 2155, piso 3, 1121 Ciudad Autónoma de Buenos Aires, Argentina
| | | | | | | |
Collapse
|
27
|
Chen J, Zolkiewska A. Force-induced unfolding simulations of the human Notch1 negative regulatory region: possible roles of the heterodimerization domain in mechanosensing. PLoS One 2011; 6:e22837. [PMID: 21829530 PMCID: PMC3145759 DOI: 10.1371/journal.pone.0022837] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2011] [Accepted: 06/30/2011] [Indexed: 02/04/2023] Open
Abstract
Notch receptors are core components of the Notch signaling pathway and play a central role in cell fate decisions during development as well as tissue homeostasis. Upon ligand binding, Notch is sequentially cleaved at the S2 site by an ADAM protease and at the S3 site by the γ-secretase complex. Recent X-ray structures of the negative regulatory region (NRR) of the Notch receptor reveal an auto-inhibited fold where three protective Lin12/Notch repeats (LNR) of the NRR shield the S2 cleavage site housed in the heterodimerization (HD) domain. One of the models explaining how ligand binding drives the NRR conformation from a protease-resistant state to a protease-sensitive one invokes a mechanical force exerted on the NRR upon ligand endocytosis. Here, we combined physics-based atomistic simulations and topology-based coarse-grained modeling to investigate the intrinsic and force-induced folding and unfolding mechanisms of the human Notch1 NRR. The simulations support that external force applied to the termini of the NRR disengages the LNR modules from the heterodimerization (HD) domain in a well-defined, largely sequential manner. Importantly, the mechanical force can further drive local unfolding of the HD domain in a functionally relevant fashion that would provide full proteolytic access to the S2 site prior to heterodimer disassociation. We further analyzed local structural features, intrinsic folding free energy surfaces, and correlated motions of the HD domain. The results are consistent with a model in which the HD domain possesses inherent mechanosensing characteristics that could be utilized during Notch activation. This potential role of the HD domain in ligand-dependent Notch activation may have implications for understanding normal and aberrant Notch signaling.
Collapse
Affiliation(s)
- Jianhan Chen
- Department of Biochemistry, Kansas State University, Manhattan, Kansas, United States of America
| | - Anna Zolkiewska
- Department of Biochemistry, Kansas State University, Manhattan, Kansas, United States of America
| |
Collapse
|
28
|
Banks SML, Cho B, Eun SH, Lee JH, Windler SL, Xie X, Bilder D, Fischer JA. The functions of auxilin and Rab11 in Drosophila suggest that the fundamental role of ligand endocytosis in notch signaling cells is not recycling. PLoS One 2011; 6:e18259. [PMID: 21448287 PMCID: PMC3063240 DOI: 10.1371/journal.pone.0018259] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2011] [Accepted: 02/23/2011] [Indexed: 12/03/2022] Open
Abstract
Notch signaling requires ligand internalization by the signal sending cells. Two endocytic proteins, epsin and auxilin, are essential for ligand internalization and signaling. Epsin promotes clathrin-coated vesicle formation, and auxilin uncoats clathrin from newly internalized vesicles. Two hypotheses have been advanced to explain the requirement for ligand endocytosis. One idea is that after ligand/receptor binding, ligand endocytosis leads to receptor activation by pulling on the receptor, which either exposes a cleavage site on the extracellular domain, or dissociates two receptor subunits. Alternatively, ligand internalization prior to receptor binding, followed by trafficking through an endosomal pathway and recycling to the plasma membrane may enable ligand activation. Activation could mean ligand modification or ligand transcytosis to a membrane environment conducive to signaling. A key piece of evidence supporting the recycling model is the requirement in signaling cells for Rab11, which encodes a GTPase critical for endosomal recycling. Here, we use Drosophila Rab11 and auxilin mutants to test the ligand recycling hypothesis. First, we find that Rab11 is dispensable for several Notch signaling events in the eye disc. Second, we find that Drosophila female germline cells, the one cell type known to signal without clathrin, also do not require auxilin to signal. Third, we find that much of the requirement for auxilin in Notch signaling was bypassed by overexpression of both clathrin heavy chain and epsin. Thus, the main role of auxilin in Notch signaling is not to produce uncoated ligand-containing vesicles, but to maintain the pool of free clathrin. Taken together, these results argue strongly that at least in some cell types, the primary function of Notch ligand endocytosis is not for ligand recycling.
Collapse
Affiliation(s)
- Susan M. L. Banks
- Section of Molecular Cell and Developmental Biology and Institute for Cell and Molecular Biology, The University of Texas at Austin, Austin, Texas, United States of America
| | - Bomsoo Cho
- Section of Molecular Cell and Developmental Biology and Institute for Cell and Molecular Biology, The University of Texas at Austin, Austin, Texas, United States of America
| | - Suk Ho Eun
- Section of Molecular Cell and Developmental Biology and Institute for Cell and Molecular Biology, The University of Texas at Austin, Austin, Texas, United States of America
| | - Ji-Hoon Lee
- Section of Molecular Cell and Developmental Biology and Institute for Cell and Molecular Biology, The University of Texas at Austin, Austin, Texas, United States of America
| | - Sarah L. Windler
- Department of Molecular and Cell Biology, University of California, Berkeley, California, United States of America
| | - Xuanhua Xie
- Section of Molecular Cell and Developmental Biology and Institute for Cell and Molecular Biology, The University of Texas at Austin, Austin, Texas, United States of America
| | - David Bilder
- Department of Molecular and Cell Biology, University of California, Berkeley, California, United States of America
| | - Janice A. Fischer
- Section of Molecular Cell and Developmental Biology and Institute for Cell and Molecular Biology, The University of Texas at Austin, Austin, Texas, United States of America
- * E-mail:
| |
Collapse
|
29
|
Terry AJ, Sturrock M, Dale JK, Maroto M, Chaplain MAJ. A spatio-temporal model of Notch signalling in the zebrafish segmentation clock: conditions for synchronised oscillatory dynamics. PLoS One 2011; 6:e16980. [PMID: 21386903 PMCID: PMC3046134 DOI: 10.1371/journal.pone.0016980] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2010] [Accepted: 01/19/2011] [Indexed: 11/19/2022] Open
Abstract
In the vertebrate embryo, tissue blocks called somites are laid down in head-to-tail succession, a process known as somitogenesis. Research into somitogenesis has been both experimental and mathematical. For zebrafish, there is experimental evidence for oscillatory gene expression in cells in the presomitic mesoderm (PSM) as well as evidence that Notch signalling synchronises the oscillations in neighbouring PSM cells. A biological mechanism has previously been proposed to explain these phenomena. Here we have converted this mechanism into a mathematical model of partial differential equations in which the nuclear and cytoplasmic diffusion of protein and mRNA molecules is explicitly considered. By performing simulations, we have found ranges of values for the model parameters (such as diffusion and degradation rates) that yield oscillatory dynamics within PSM cells and that enable Notch signalling to synchronise the oscillations in two touching cells. Our model contains a Hill coefficient that measures the co-operativity between two proteins (Her1, Her7) and three genes (her1, her7, deltaC) which they inhibit. This coefficient appears to be bounded below by the requirement for oscillations in individual cells and bounded above by the requirement for synchronisation. Consistent with experimental data and a previous spatially non-explicit mathematical model, we have found that signalling can increase the average level of Her1 protein. Biological pattern formation would be impossible without a certain robustness to variety in cell shape and size; our results possess such robustness. Our spatially-explicit modelling approach, together with new imaging technologies that can measure intracellular protein diffusion rates, is likely to yield significant new insight into somitogenesis and other biological processes.
Collapse
Affiliation(s)
- Alan J Terry
- Division of Mathematics, University of Dundee, Dundee, United Kingdom.
| | | | | | | | | |
Collapse
|
30
|
Hansson EM, Lanner F, Das D, Mutvei A, Marklund U, Ericson J, Farnebo F, Stumm G, Stenmark H, Andersson ER, Lendahl U. Control of Notch-ligand endocytosis by ligand-receptor interaction. J Cell Sci 2011; 123:2931-42. [PMID: 20720151 DOI: 10.1242/jcs.073239] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
In Notch signaling, cell-bound ligands activate Notch receptors on juxtaposed cells, but the relationship between ligand endocytosis, ubiquitylation and ligand-receptor interaction remains poorly understood. To study the specific role of ligand-receptor interaction, we identified a missense mutant of the Notch ligand Jagged1 (Nodder, Ndr) that failed to interact with Notch receptors, but retained a cellular distribution that was similar to wild-type Jagged1 (Jagged1(WT)) in the absence of active Notch signaling. Both Jagged1(WT) and Jagged1(Ndr) interacted with the E3 ubiquitin ligase Mind bomb, but only Jagged1(WT) showed enhanced ubiquitylation after co-culture with cells expressing Notch receptor. Cells expressing Jagged1(WT), but not Jagged1(Ndr), trans-endocytosed the Notch extracellular domain (NECD) into the ligand-expressing cell, and NECD colocalized with Jagged1(WT) in early endosomes, multivesicular bodies and lysosomes, suggesting that NECD is routed through the endocytic degradation pathway. When coexpressed in the same cell, Jagged1(Ndr) did not exert a dominant-negative effect over Jagged1(WT) in terms of receptor activation. Finally, in Jag1(Ndr/Ndr) mice, the ligand was largely accumulated at the cell surface, indicating that engagement of the Notch receptor is important for ligand internalization in vivo. In conclusion, the interaction-dead Jagged1(Ndr) ligand provides new insights into the specific role of receptor-ligand interaction in the intracellular trafficking of Notch ligands.
Collapse
Affiliation(s)
- Emil M Hansson
- Department of Cell and Molecular Biology, Medical Nobel Institute, Karolinska Institute, SE-171 77 Stockholm, Sweden
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
31
|
Williamson WR, Yang T, Terman JR, Hiesinger PR. Guidance receptor degradation is required for neuronal connectivity in the Drosophila nervous system. PLoS Biol 2010; 8:e1000553. [PMID: 21151882 PMCID: PMC2998435 DOI: 10.1371/journal.pbio.1000553] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2010] [Accepted: 10/21/2010] [Indexed: 12/23/2022] Open
Abstract
Axon pathfinding and synapse formation rely on precise spatiotemporal localization of guidance receptors. However, little is known about the neuron-specific intracellular trafficking mechanisms that underlie the sorting and activity of these receptors. Here we show that loss of the neuron-specific v-ATPase subunit a1 leads to progressive endosomal guidance receptor accumulations after neuronal differentiation. In the embryo and in adult photoreceptors, these accumulations occur after axon pathfinding and synapse formation is complete. In contrast, receptor missorting occurs sufficiently early in neurons of the adult central nervous system to cause connectivity defects. An increase of guidance receptors, but not of membrane proteins without signaling function, causes specific gain-of-function phenotypes. A point mutant that promotes sorting but prevents degradation reveals spatiotemporally specific guidance receptor turnover and accelerates developmental defects in photoreceptors and embryonic motor neurons. Our findings indicate that a neuron-specific endolysosomal degradation mechanism is part of the cell biological machinery that regulates guidance receptor turnover and signaling.
Collapse
Affiliation(s)
- W. Ryan Williamson
- Department of Physiology and Green Center for Systems Biology, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas, United States of America
| | - Taehong Yang
- Departments of Neuroscience and Pharmacology, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas, United States of America
| | - Jonathan R. Terman
- Departments of Neuroscience and Pharmacology, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas, United States of America
| | - P. Robin Hiesinger
- Department of Physiology and Green Center for Systems Biology, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas, United States of America
- * E-mail:
| |
Collapse
|
32
|
Meng H, Zhang X, Lee SJ, Strickland DK, Lawrence DA, Wang MM. Low density lipoprotein receptor-related protein-1 (LRP1) regulates thrombospondin-2 (TSP2) enhancement of Notch3 signaling. J Biol Chem 2010; 285:23047-55. [PMID: 20472562 DOI: 10.1074/jbc.m110.144634] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Intracellular trafficking of Notch and Notch ligands modulates signaling, suggesting that choreography of ligand and receptor translocation is essential for optimal Notch activity. Indeed, a major model for Notch signaling posits that Notch trans-endocytosis into the ligand-expressing (signal sending) cell is a key driving force for Notch signal transduction. The extracellular protein thrombospondin-2 (TSP2) enhances Notch signaling and binds to both Jagged1 and Notch3 ectodomains, potentially bridging two essential extracellular components of Notch signaling. We investigated the role of low density lipoprotein receptor-related protein-1 (LRP1), a TSP2 receptor, in the regulation of Notch3 signaling. TSP2 potentiation of Notch is blocked by the receptor-associated protein (an inhibitor of low density lipoprotein receptor-related protein function) and requires LRP1 expression in the signal-sending cell. TSP2 stimulates Notch3 endocytosis into wild type fibroblasts but not LRP1-deficient fibroblasts. Finally, recombinant Notch3 and Jagged1 interact with the LRP1 85-kDa B-chain, a subunit that lacks known ligand binding function. Our data suggest that LRP1 and TSP2 stimulate Notch activity by driving trans-endocytosis of the Notch ectodomain into the signal-sending cell and demonstrate a novel, non-cell autonomous function of LRP1 in cell-cell signaling.
Collapse
Affiliation(s)
- He Meng
- Department of Neurology, University of Michigan, Ann Arbor, Michigan 48109-5622, USA
| | | | | | | | | | | |
Collapse
|
33
|
Wang Y, Chen Z, Bergmann A. Regulation of EGFR and Notch signaling by distinct isoforms of D-cbl during Drosophila development. Dev Biol 2010; 342:1-10. [PMID: 20302857 DOI: 10.1016/j.ydbio.2010.03.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2008] [Revised: 03/08/2010] [Accepted: 03/10/2010] [Indexed: 01/25/2023]
Abstract
Cells receive and interpret extracellular signals to regulate cellular responses such as proliferation, cell survival and differentiation. However, proper inactivation of these signals is critical for appropriate homeostasis. Cbl proteins are E3-ubiquitin ligases that restrict receptor tyrosine kinase (RTK) signaling, most notably EGFR (Epidermal Growth Factor Receptor), via the endocytic pathway. Consistently, many mutant phenotypes of Drosophila cbl (D-cbl) are due to inappropriate activation of EGFR signaling. However, not all D-cbl phenotypes can be explained by increased EGFR activity. Here, we report that D-Cbl also negatively regulates Notch activity during eye and wing development. D-cbl produces two isoforms by alternative splicing. The long isoform, D-CblL, regulates the EGFR. We found that the short isoform, D-CblS, preferentially restricts Notch signaling. Specifically, our data imply that D-CblS controls the activity of the Notch ligand Delta. Taken together, these data suggest that D-Cbl controls the EGFR and Notch/Delta signaling pathways through production of two alternatively spliced isoforms during development in Drosophila.
Collapse
Affiliation(s)
- Yuan Wang
- The University of Texas M.D. Anderson Cancer Center, Department of Biochemistry & Molecular Biology, 1515 Holcombe Blvd.-Unit 1000, Houston, TX 77030, USA
| | | | | |
Collapse
|
34
|
Tallafuss A, Trepman A, Eisen JS. DeltaA mRNA and protein distribution in the zebrafish nervous system. Dev Dyn 2010; 238:3226-36. [PMID: 19924821 DOI: 10.1002/dvdy.22136] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Physical interaction between the transmembrane proteins Delta and Notch allows only a subset of neural precursors to become neurons, as well as regulating other aspects of neural development. To examine the localization of Delta protein during neural development, we generated an antibody specific to zebrafish Delta A (Dla). Here, we describe for the first time the subcellular localization of Dla protein in distinct puncta at cell cortex and/or membrane, supporting the function of Dla in direct cell-cell communication. In situ RNA hybridization and immunohistochemistry revealed dynamic, coordinated expression patterns of dla mRNA and Dla protein in the developing and adult zebrafish nervous system. Dla expression is mostly excluded from differentiated neurons and is maintained in putative precursor cells at least until larval stages. In the adult brain, dla mRNA and Dla protein are expressed in proliferative zones normally associated with stem cells.
Collapse
|
35
|
Richardson ECN, Pichaud F. Crumbs is required to achieve proper organ size control during Drosophila head development. Development 2010; 137:641-50. [PMID: 20110329 DOI: 10.1242/dev.041913] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Crumbs (Crb) is a conserved apical polarity determinant required for zonula adherens specification and remodelling during Drosophila development. Interestingly, crb function in maintaining apicobasal polarity appears largely dispensable in primary epithelia such as the imaginal discs. Here, we show that crb function is not required for maintaining epithelial integrity during the morphogenesis of the Drosophila head and eye. However, although crb mutant heads are properly developed, they are also significantly larger than their wild-type counterparts. We demonstrate that in the eye, this is caused by an increase in cell proliferation that can be attributed to an increase in ligand-dependent Notch (N) signalling. Moreover, we show that in crb mutant cells, ectopic N activity correlates with an increase in N and Delta endocytosis. These data indicate a role for Crb in modulating endocytosis at the apical epithelial plasma membrane, which we demonstrate is independent of Crb function in apicobasal polarity. Overall, our work reveals a novel function for Crb in limiting ligand-dependent transactivation of the N receptor at the epithelial cell membrane.
Collapse
Affiliation(s)
- Emily C N Richardson
- MRC Laboratory for Molecular Cell Biology and Cell Biology Unit, University College London, London, UK
| | | |
Collapse
|
36
|
Mathur D, Bost A, Driver I, Ohlstein B. A transient niche regulates the specification of Drosophila intestinal stem cells. Science 2010; 327:210-3. [PMID: 20056890 DOI: 10.1126/science.1181958] [Citation(s) in RCA: 140] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Stem cell niches are locations where stem cells reside and self-renew. Although studies have shown how niches maintain stem cell fate during tissue homeostasis, less is known about their roles in establishing stem cells. The adult Drosophila midgut is maintained by intestinal stem cells (ISCs); however, how they are established is unknown. Here, we show that an ISC progenitor generates a niche cell via Notch signaling. This niche uses the bone morphogenetic protein 2/4 homolog, decapentaplegic, to allow progenitors to divide in an undifferentiated state and subsequently breaks down and dies, resulting in the specification of ISCs in the adult midgut. Our results demonstrate a paradigm for stem cell-niche biology, where progenitors generate transient niches that determine stem cell fate and may give insights into stem cell specification in other tissues.
Collapse
Affiliation(s)
- Divya Mathur
- Department of Genetics and Development, Columbia University Medical Center, New York, NY 10032, USA
| | | | | | | |
Collapse
|
37
|
Abstract
Notch signaling induced by canonical Notch ligands is critical for normal embryonic development and tissue homeostasis through the regulation of a variety of cell fate decisions and cellular processes. Activation of Notch signaling is normally tightly controlled by direct interactions with ligand-expressing cells, and dysregulated Notch signaling is associated with developmental abnormalities and cancer. While canonical Notch ligands are responsible for the majority of Notch signaling, a diverse group of structurally unrelated noncanonical ligands has also been identified that activate Notch and likely contribute to the pleiotropic effects of Notch signaling. Soluble forms of both canonical and noncanonical ligands have been isolated, some of which block Notch signaling and could serve as natural inhibitors of this pathway. Ligand activity can also be indirectly regulated by other signaling pathways at the level of ligand expression, serving to spatiotemporally compartmentalize Notch signaling activity and integrate Notch signaling into a molecular network that orchestrates developmental events. Here, we review the molecular mechanisms underlying the dual role of Notch ligands as activators and inhibitors of Notch signaling. Additionally, evidence that Notch ligands function independent of Notch is presented. We also discuss how ligand posttranslational modification, endocytosis, proteolysis, and spatiotemporal expression regulate their signaling activity.
Collapse
Affiliation(s)
- Brendan D'Souza
- Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | | | | |
Collapse
|
38
|
Abstract
Notch signaling occurs through direct interaction between Notch, the receptor, and its ligands, presented on the surface of neighboring cells. Endocytosis has been shown to be essential for Notch signal activation in both signal-sending and signal-receiving cells, and numerous genes involved in vesicle trafficking have recently been shown to act as key regulators of the pathway. Defects in vesicle trafficking can lead to gain- or loss-of-function defects in a context-dependent manner. Here, we discuss how endocytosis and vesicle trafficking regulate Notch signaling in both signal-sending and signal-receiving cells. We will introduce the key players in different trafficking steps, and further illustrate how they impact the signal outcome. Some of these players act as general factors and modulate Notch signaling in all contexts, whereas others modulate signaling in a context-specific fashion. We also discuss Notch signaling during mechanosensory organ development in the fly to exemplify how endocytosis and vesicle trafficking are effectively used to determine correct cell fates. In summary, endocytosis plays an essential role in Notch signaling, whereas intracellular vesicle trafficking often plays a context-dependent or regulatory role, leading to divergent outcomes in different developmental contexts.
Collapse
|
39
|
Tse WKF, Eisenhaber B, Ho SHK, Ng Q, Eisenhaber F, Jiang YJ. Genome-wide loss-of-function analysis of deubiquitylating enzymes for zebrafish development. BMC Genomics 2009; 10:637. [PMID: 20040115 PMCID: PMC2809080 DOI: 10.1186/1471-2164-10-637] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2009] [Accepted: 12/30/2009] [Indexed: 02/02/2023] Open
Abstract
Background Deconjugation of ubiquitin and/or ubiquitin-like modified protein substrates is essential to modulate protein-protein interactions and, thus, signaling processes in cells. Although deubiquitylating (deubiquitinating) enzymes (DUBs) play a key role in this process, however, their function and regulation remain insufficiently understood. The "loss-of-function" phenotype studies can provide important information to elucidate the gene function, and zebrafish is an excellent model for this goal. Results From an in silico genome-wide search, we found more than 90 putative DUBs encoded in the zebrafish genome belonging to six different subclasses. Out of them, 85 from five classical subclasses have been tested with morpholino (MO) knockdown experiments and 57 of them were found to be important in early development of zebrafish. These DUB morphants resulted in a complex and pleiotropic phenotype that, regardless of gene target, always affected the notochord. Based on the huC neuronal marker expression, we grouped them into five sets (groups I to V). Group I DUBs (otud7b, uchl3 and bap1) appear to be involved in the Notch signaling pathway based on the neuronal hyperplasia, while group IV DUBs (otud4, usp5, usp15 and usp25) play a critical role in dorsoventral patterning through the BMP pathway. Conclusion We have identified an exhaustive list of genes in the zebrafish genome belonging to the five established classes of DUBs. Additionally, we performed the corresponding MO knockdown experiments in zebrafish as well as functional studies for a subset of the predicted DUB genes. The screen results in this work will stimulate functional follow-up studies of potential DUB genes using the zebrafish model system.
Collapse
Affiliation(s)
- William K F Tse
- Laboratory of Developmental Signalling and Patterning, Genes and Development Division, Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, Singapore.
| | | | | | | | | | | |
Collapse
|
40
|
Ossipova O, Ezan J, Sokol SY. PAR-1 phosphorylates Mind bomb to promote vertebrate neurogenesis. Dev Cell 2009; 17:222-33. [PMID: 19686683 DOI: 10.1016/j.devcel.2009.06.010] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2008] [Revised: 04/04/2009] [Accepted: 06/17/2009] [Indexed: 12/25/2022]
Abstract
Generation of neurons in the vertebrate central nervous system requires a complex transcriptional regulatory network and signaling processes in polarized neuroepithelial progenitor cells. Here we demonstrate that neurogenesis in the Xenopus neural plate in vivo and mammalian neural progenitors in vitro involves intrinsic antagonistic activities of the polarity proteins PAR-1 and aPKC. Furthermore, we show that Mind bomb (Mib), a ubiquitin ligase that promotes Notch ligand trafficking and activity, is a crucial molecular substrate for PAR-1. The phosphorylation of Mib by PAR-1 results in Mib degradation, repression of Notch signaling, and stimulation of neuronal differentiation. These observations suggest a conserved mechanism for neuronal fate determination that might operate during asymmetric divisions of polarized neural progenitor cells.
Collapse
Affiliation(s)
- Olga Ossipova
- Department of Developmental and Regenerative Biology, Mount Sinai School of Medicine, New York, NY 10029, USA
| | | | | |
Collapse
|
41
|
Gazave E, Lapébie P, Richards GS, Brunet F, Ereskovsky AV, Degnan BM, Borchiellini C, Vervoort M, Renard E. Origin and evolution of the Notch signalling pathway: an overview from eukaryotic genomes. BMC Evol Biol 2009; 9:249. [PMID: 19825158 PMCID: PMC2770060 DOI: 10.1186/1471-2148-9-249] [Citation(s) in RCA: 171] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2009] [Accepted: 10/13/2009] [Indexed: 12/20/2022] Open
Abstract
Background Of the 20 or so signal transduction pathways that orchestrate cell-cell interactions in metazoans, seven are involved during development. One of these is the Notch signalling pathway which regulates cellular identity, proliferation, differentiation and apoptosis via the developmental processes of lateral inhibition and boundary induction. In light of this essential role played in metazoan development, we surveyed a wide range of eukaryotic genomes to determine the origin and evolution of the components and auxiliary factors that compose and modulate this pathway. Results We searched for 22 components of the Notch pathway in 35 different species that represent 8 major clades of eukaryotes, performed phylogenetic analyses and compared the domain compositions of the two fundamental molecules: the receptor Notch and its ligands Delta/Jagged. We confirm that a Notch pathway, with true receptors and ligands is specific to the Metazoa. This study also sheds light on the deep ancestry of a number of genes involved in this pathway, while other members are revealed to have a more recent origin. The origin of several components can be accounted for by the shuffling of pre-existing protein domains, or via lateral gene transfer. In addition, certain domains have appeared de novo more recently, and can be considered metazoan synapomorphies. Conclusion The Notch signalling pathway emerged in Metazoa via a diversity of molecular mechanisms, incorporating both novel and ancient protein domains during eukaryote evolution. Thus, a functional Notch signalling pathway was probably present in Urmetazoa.
Collapse
Affiliation(s)
- Eve Gazave
- Aix-Marseille Universités, Centre d'Océanologie de Marseille, Station marine d'Endoume - CNRS UMR 6540-DIMAR, rue de Batterie des Lions, 13007 Marseille, France.
| | | | | | | | | | | | | | | | | |
Collapse
|
42
|
He F, Saito K, Kobayashi N, Harada T, Watanabe S, Kigawa T, Güntert P, Ohara O, Tanaka A, Unzai S, Muto Y, Yokoyama S. Structural and Functional Characterization of the NHR1 Domain of the Drosophila Neuralized E3 Ligase in the Notch Signaling Pathway. J Mol Biol 2009; 393:478-95. [DOI: 10.1016/j.jmb.2009.08.020] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2009] [Revised: 08/03/2009] [Accepted: 08/10/2009] [Indexed: 01/05/2023]
|
43
|
Shalaby NA, Parks AL, Morreale EJ, Osswalt MC, Pfau KM, Pierce EL, Muskavitch MAT. A screen for modifiers of notch signaling uncovers Amun, a protein with a critical role in sensory organ development. Genetics 2009; 182:1061-76. [PMID: 19448274 PMCID: PMC2728848 DOI: 10.1534/genetics.108.099986] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2009] [Accepted: 05/11/2009] [Indexed: 12/14/2022] Open
Abstract
Notch signaling is an evolutionarily conserved pathway essential for many cell fate specification events during metazoan development. We conducted a large-scale transposon-based screen in the developing Drosophila eye to identify genes involved in Notch signaling. We screened 10,447 transposon lines from the Exelixis collection for modifiers of cell fate alterations caused by overexpression of the Notch ligand Delta and identified 170 distinct modifier lines that may affect up to 274 genes. These include genes known to function in Notch signaling, as well as a large group of characterized and uncharacterized genes that have not been implicated in Notch pathway function. We further analyze a gene that we have named Amun and show that it encodes a protein that localizes to the nucleus and contains a putative DNA glycosylase domain. Genetic and molecular analyses of Amun show that altered levels of Amun function interfere with cell fate specification during eye and sensory organ development. Overexpression of Amun decreases expression of the proneural transcription factor Achaete, and sensory organ loss caused by Amun overexpression can be rescued by coexpression of Achaete. Taken together, our data suggest that Amun acts as a transcriptional regulator that can affect cell fate specification by controlling Achaete levels.
Collapse
Affiliation(s)
- Nevine A Shalaby
- Biology Department, Boston College, Chestnut Hill, Massachusetts 02467, USA
| | | | | | | | | | | | | |
Collapse
|
44
|
Schmidt MHH, Bicker F, Nikolic I, Meister J, Babuke T, Picuric S, Müller-Esterl W, Plate KH, Dikic I. Epidermal growth factor-like domain 7 (EGFL7) modulates Notch signalling and affects neural stem cell renewal. Nat Cell Biol 2009; 11:873-80. [PMID: 19503073 DOI: 10.1038/ncb1896] [Citation(s) in RCA: 110] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2008] [Accepted: 03/13/2009] [Indexed: 01/08/2023]
Abstract
Epidermal growth factor-like domain 7 (EGFL7) is a secreted factor implicated in cellular responses such as cell migration and blood vessel formation; however the molecular mechanisms underlying the effects of EGFL7 are largely unknown. Here we have identified transmembrane receptors of the Notch family as EGFL7-binding molecules. Secreted EGFL7 binds to a region in Notch involved in ligand-mediated receptor activation, thus acting as an antagonist of Notch signalling. Expression of EGFL7 in neural stem cells (NSCs) in vitro decreased Notch-specific signalling and consequently, reduced proliferation and self-renewal of NSCs. Such altered Notch signalling caused a shift in the differentiation pattern of cultured NSCs towards an excess of neurons and oligodendrocytes. We identified neurons as a source of EGFL7 in the brain, suggesting that brain-derived EGFL7 acts as an endogenous antagonist of Notch signalling that regulates proliferation and differentiation of subventricular zone-derived adult NSCs.
Collapse
Affiliation(s)
- Mirko H H Schmidt
- Institute of Biochemistry II, Johann Wolfgang Goethe University School of Medicine, Frankfurt am Main, Germany.
| | | | | | | | | | | | | | | | | |
Collapse
|
45
|
Fürthauer M, González-Gaitán M. Endocytosis, asymmetric cell division, stem cells and cancer: unus pro omnibus, omnes pro uno. Mol Oncol 2009; 3:339-53. [PMID: 19581131 DOI: 10.1016/j.molonc.2009.05.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2009] [Accepted: 05/25/2009] [Indexed: 12/17/2022] Open
Abstract
Carcinogenesis can be initiated in adult stem cells, suggesting that tumours arise as a consequence of stem-cell dysfunction. In the fruitfly, cancer arises in stem cells that fail to undergo asymmetric cell division. In flies and mammals, a specific regulation of the endocytic trafficking machinery allows stem cells to self-renew and generate the differentiating cells required to form and maintain mature organs. We review recent findings suggesting that an understanding of the relationship between endocytosis, asymmetric cell division, stem cells and cancer will be crucial to unravel the cell biological basis of tumourigenesis.
Collapse
Affiliation(s)
- Maximilian Fürthauer
- Department of Biochemistry, University of Geneva, Sciences II, CH-1211 Geneva 4, Switzerland.
| | | |
Collapse
|
46
|
|
47
|
Mancuso MR, Kuhnert F, Kuo CJ. Developmental angiogenesis of the central nervous system. Lymphat Res Biol 2009; 6:173-80. [PMID: 19093790 DOI: 10.1089/lrb.2008.1014] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The vasculature of the central nervous system (CNS) is highly specialized with a blood-brain-barrier, reciprocal neuroepithelial-endothelial cell interactions and extensive pericyte coverage. Developmentally, numerous important signaling pathways participate in CNS angiogenesis to orchestrate the precise timing and spatial arrangement of the complex CNS vascular network. From a therapeutic standpoint, the CNS vasculature has attracted increased attention since many human ailments, such as stroke, retinopathy, cancer and autoimmune disease are intimately associated with the biology of CNS blood vessels. This review focuses on growth factor pathways that have been shown to be important in developmental CNS vascularization through studies of mouse genetic models and human diseases.
Collapse
Affiliation(s)
- Michael R Mancuso
- Stanford University School of Medicine. Division of Hematology, Stanford, CA
| | | | | |
Collapse
|
48
|
Chong M, Liao M, Drapeau P. The vesicular integral protein-like gene is essential for development of a mechanosensory system in zebrafish. Dev Neurobiol 2008; 68:1391-405. [DOI: 10.1002/dneu.20671] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
49
|
Abstract
The Notch signaling pathway regulates a diverse array of cell types and cellular processes and is tightly regulated by ligand binding. Both canonical and noncanonical Notch ligands have been identified that may account for some of the pleiotropic nature associated with Notch signaling. This review focuses on the molecular mechanisms by which Notch ligands function as signaling agonists and antagonists, and discusses different modes of activating ligands as well as findings that support intrinsic ligand signaling activity independent of Notch. Post-translational modification, proteolytic processing, endocytosis and membrane trafficking, as well as interactions with the actin cytoskeleton may contribute to the recently appreciated multifunctionality of Notch ligands. The regulation of Notch ligand expression by other signaling pathways provides a mechanism to coordinate Notch signaling with multiple cellular and developmental cues. The association of Notch ligands with inherited human disorders and cancer highlights the importance of understanding the molecular nature and activities intrinsic to Notch ligands. Oncogene (2008) 27, 5148-5167; doi:10.1038/onc.2008.229.
Collapse
Affiliation(s)
- B D'Souza
- Department of Biological Chemistry, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095-1737, USA
| | | | | |
Collapse
|
50
|
Diks SH, Sartori da Silva MA, Hillebrands JL, Bink RJ, Versteeg HH, van Rooijen C, Brouwers A, Chitnis AB, Peppelenbosch MP, Zivkovic D. d-Asb11 is an essential mediator of canonical Delta–Notch signalling. Nat Cell Biol 2008; 10:1190-8. [DOI: 10.1038/ncb1779] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2008] [Accepted: 07/24/2008] [Indexed: 01/05/2023]
|