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Perdaens O, Bottemanne P, van Pesch V. MicroRNAs dysregulated in multiple sclerosis affect the differentiation of CG-4 cells, an oligodendrocyte progenitor cell line. Front Cell Neurosci 2024; 18:1336439. [PMID: 38486710 PMCID: PMC10937391 DOI: 10.3389/fncel.2024.1336439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Accepted: 01/24/2024] [Indexed: 03/17/2024] Open
Abstract
Introduction Demyelination is one of the hallmarks of multiple sclerosis (MS). While remyelination occurs during the disease, it is incomplete from the start and strongly decreases with its progression, mainly due to the harm to oligodendrocyte progenitor cells (OPCs), causing irreversible neurological deficits and contributing to neurodegeneration. Therapeutic strategies promoting remyelination are still very preliminary and lacking within the current treatment panel for MS. Methods In a previous study, we identified 21 microRNAs dysregulated mostly in the CSF of relapsing and/or remitting MS patients. In this study we transfected the mimics/inhibitors of several of these microRNAs separately in an OPC cell line, called CG-4. We aimed (1) to phenotypically characterize their effect on OPC differentiation and (2) to identify corroborating potential mRNA targets via immunocytochemistry, RT-qPCR analysis, RNA sequencing, and Gene Ontology enrichment analysis. Results We observed that the majority of 13 transfected microRNA mimics decreased the differentiation of CG-4 cells. We demonstrate, by RNA sequencing and independent RT-qPCR analyses, that miR-33-3p, miR-34c-5p, and miR-124-5p arrest OPC differentiation at a late progenitor stage and miR-145-5p at a premyelinating stage as evidenced by the downregulation of premyelinating oligodendrocyte (OL) [Tcf7l2, Cnp (except for miR-145-5p)] and mature OL (Plp1, Mbp, and Mobp) markers, whereas only miR-214-3p promotes OPC differentiation. We further propose a comprehensive exploration of their change in cell fate through Gene Ontology enrichment analysis. We finally confirm by RT-qPCR analyses the downregulation of several predicted mRNA targets for each microRNA that possibly support their effect on OPC differentiation by very distinctive mechanisms, of which some are still unexplored in OPC/OL physiology. Conclusion miR-33-3p, miR-34c-5p, and miR-124-5p arrest OPC differentiation at a late progenitor stage and miR-145-5p at a premyelinating stage, whereas miR-214-3p promotes the differentiation of CG-4 cells. We propose several potential mRNA targets and hypothetical mechanisms by which each microRNA exerts its effect. We hereby open new perspectives in the research on OPC differentiation and the pathophysiology of demyelination/remyelination, and possibly even in the search for new remyelinating therapeutic strategies in the scope of MS.
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Affiliation(s)
- Océane Perdaens
- Neurochemistry Group, Institute of NeuroScience, Université catholique de Louvain (UCLouvain), Brussels, Belgium
| | - Pauline Bottemanne
- Bioanalysis and Pharmacology of Bioactive Lipids, Louvain Drug Research Institute, Université catholique de Louvain (UCLouvain), Brussels, Belgium
| | - Vincent van Pesch
- Neurochemistry Group, Institute of NeuroScience, Université catholique de Louvain (UCLouvain), Brussels, Belgium
- Department of Neurology, Cliniques universitaires Saint-Luc, Université catholique de Louvain (UCLouvain), Brussels, Belgium
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2
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O'Keeffe C, Greenwald I. EGFR signal transduction is downregulated in C. elegans vulval precursor cells during dauer diapause. Development 2022; 149:dev201094. [PMID: 36227589 PMCID: PMC9793418 DOI: 10.1242/dev.201094] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 10/04/2022] [Indexed: 11/05/2022]
Abstract
Caenorhabditis elegans larvae display developmental plasticity in response to environmental conditions: in adverse conditions, second-stage larvae enter a reversible, long-lived dauer stage instead of proceeding to reproductive adulthood. Dauer entry interrupts vulval induction and is associated with a reprogramming-like event that preserves the multipotency of vulval precursor cells (VPCs), allowing vulval development to reinitiate if conditions improve. Vulval induction requires the LIN-3/EGF-like signal from the gonad, which activates EGFR-Ras-ERK signal transduction in the nearest VPC, P6.p. Here, using a biosensor and live imaging we show that EGFR-Ras-ERK activity is downregulated in P6.p in dauers. We investigated this process using gene mutations or transgenes to manipulate different steps of the pathway, and by analyzing LET-23/EGFR subcellular localization during dauer life history. We found that the response to EGF is attenuated at or upstream of Ras activation, and discuss potential membrane-associated mechanisms that could achieve this. We also describe other findings pertaining to the maintenance of VPC competence and quiescence in dauer larvae. Our analysis indicates that VPCs have L2-like and unique dauer stage features rather than features of L3 VPCs in continuous development.
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Affiliation(s)
- Catherine O'Keeffe
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA
| | - Iva Greenwald
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA
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3
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Rasmussen NR, Reiner DJ. Nuclear translocation of the tagged endogenous MAPK MPK-1 denotes a subset of activation events in C. elegans development. J Cell Sci 2021; 134:272044. [PMID: 34341823 PMCID: PMC8445601 DOI: 10.1242/jcs.258456] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Accepted: 07/14/2021] [Indexed: 11/20/2022] Open
Abstract
The extracellular signal-regulated kinases (ERKs) are mitogen-activated protein kinases (MAPKs) that are utilized downstream of Ras to Raf to MEK signaling to control activation of a wide array of targets. Activation of ERKs is elevated in Ras-driven tumors and RASopathies, and thus is a target for pharmacological inhibition. Regulatory mechanisms of ERK activation have been studied extensively in vitro and in cultured cells, but little in living animals. In this study, we tagged the Caenorhabditis elegans ERK-encoding gene, mpk-1. MPK-1 is ubiquitously expressed with elevated expression in certain contexts. We detected cytosol-to-nuclear translocation of MPK-1 in maturing oocytes and hence validated nuclear translocation as a reporter of some activation events. During patterning of vulval precursor cells (VPCs), MPK-1 is necessary and sufficient for the central cell, P6.p, to assume the primary fate. Yet MPK-1 translocates to the nuclei of all six VPCs in a temporal and concentration gradient centered on P6.p. This observation contrasts with previous results using the ERK nuclear kinase translocation reporter of substrate activation, raising questions about mechanisms and indicators of MPK-1 activation. This system and reagent promise to provide critical insights into the regulation of MPK-1 activation within a complex intercellular signaling network. Summary: Tagged endogenous C. elegans MPK-1 shows activation-dependent cytosol-to-nuclear translocation. This tool provides novel insights into MPK-1 localization compared with other markers of in vivo ERK activation.
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Affiliation(s)
- Neal R Rasmussen
- Institute of Biosciences and Technology, College of Medicine, Texas A&M Health Science Center, Texas A&M University, Houston, 77030, USA
| | - David J Reiner
- Institute of Biosciences and Technology, College of Medicine, Texas A&M Health Science Center, Texas A&M University, Houston, 77030, USA
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4
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Gauthier KD, Rocheleau CE. Golgi localization of the LIN-2/7/10 complex points to a role in basolateral secretion of LET-23 EGFR in the Caenorhabditiselegans vulval precursor cells. Development 2021; 148:dev194167. [PMID: 33526581 PMCID: PMC10692275 DOI: 10.1242/dev.194167] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 01/25/2021] [Indexed: 12/28/2022]
Abstract
The evolutionarily conserved LIN-2 (CASK)/LIN-7 (Lin7A-C)/LIN-10 (APBA1) complex plays an important role in regulating spatial organization of membrane proteins and signaling components. In Caenorhabditiselegans, the complex is essential for the development of the vulva by promoting the localization of the sole Epidermal growth factor receptor (EGFR) ortholog LET-23 to the basolateral membrane of the vulva precursor cells where it can specify the vulval cell fate. To understand how the LIN-2/7/10 complex regulates receptor localization, we determined its expression and localization during vulva development. We found that LIN-7 colocalizes with LET-23 EGFR at the basolateral membrane, whereas the LIN-2/7/10 complex colocalizes with LET-23 EGFR at cytoplasmic punctae that mostly overlap with the Golgi. Furthermore, LIN-10 recruits LIN-2, which in turn recruits LIN-7. We demonstrate that the complex forms in vivo with a particularly strong interaction and colocalization between LIN-2 and LIN-7, consistent with them forming a subcomplex. Thus, the LIN-2/7/10 complex forms on the Golgi on which it likely targets LET-23 EGFR trafficking to the basolateral membrane rather than functioning as a tether.
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Affiliation(s)
- Kimberley D Gauthier
- Division of Endocrinology and Metabolism, Department of Medicine, and Department of Anatomy and Cell Biology, McGill University; and the Metabolic Disorders and Complications Program, Centre for Translational Biology, Research Institute of the McGill University Health Centre, Montreal, QC H4A 3J1, Canada
| | - Christian E Rocheleau
- Division of Endocrinology and Metabolism, Department of Medicine, and Department of Anatomy and Cell Biology, McGill University; and the Metabolic Disorders and Complications Program, Centre for Translational Biology, Research Institute of the McGill University Health Centre, Montreal, QC H4A 3J1, Canada
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5
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Luo KL, Underwood RS, Greenwald I. Positive autoregulation of lag-1 in response to LIN-12 activation in cell fate decisions during C. elegans reproductive system development. Development 2020; 147:dev.193482. [PMID: 32839181 DOI: 10.1242/dev.193482] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 08/11/2020] [Indexed: 12/11/2022]
Abstract
During animal development, ligand binding releases the intracellular domain of LIN-12/Notch by proteolytic cleavage to translocate to the nucleus, where it associates with the DNA-binding protein LAG-1/CSL to activate target gene transcription. We investigated the spatiotemporal regulation of LAG-1/CSL expression in Caenorhabditis elegans and observed that an increase in endogenous LAG-1 levels correlates with LIN-12/Notch activation in different cell contexts during reproductive system development. We show that this increase is via transcriptional upregulation by creating a synthetic endogenous operon, and identified an enhancer region that contains multiple LAG-1 binding sites (LBSs) embedded in a more extensively conserved high occupancy target (HOT) region. We show that these LBSs are necessary for upregulation in response to LIN-12/Notch activity, indicating that lag-1 engages in direct positive autoregulation. Deletion of the HOT region from endogenous lag-1 reduced LAG-1 levels and abrogated positive autoregulation, but did not cause hallmark cell fate transformations associated with loss of lin-12/Notch or lag-1 activity. Instead, later somatic reproductive system defects suggest that proper transcriptional regulation of lag-1 confers robustness to somatic reproductive system development.
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Affiliation(s)
- Katherine Leisan Luo
- Integrated Program in Cellular, Molecular and Biophysical Studies, Columbia University Vagelos College of Physicians and Surgeons, New York, NY 10032, USA
| | - Ryan S Underwood
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA
| | - Iva Greenwald
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA
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6
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Maxeiner S, Grolleman J, Schmid T, Kammenga J, Hajnal A. The hypoxia-response pathway modulates RAS/MAPK-mediated cell fate decisions in Caenorhabditis elegans. Life Sci Alliance 2019; 2:e201800255. [PMID: 31126994 PMCID: PMC6536719 DOI: 10.26508/lsa.201800255] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 05/16/2019] [Accepted: 05/17/2019] [Indexed: 01/01/2023] Open
Abstract
Animals need to adjust many cellular functions to oxygen availability to adapt to changing environmental conditions. We have used the nematode Caenorhabditis elegans as a model to investigate how variations in oxygen concentrations affect cell fate specification during development. Here, we show that several processes controlled by the conserved RTK/RAS/MAPK pathway are sensitive to changes in the atmospheric oxygen concentration. In the vulval precursor cells (VPCs), the hypoxia-inducible factor HIF-1 activates the expression of the nuclear hormone receptor NHR-57 to counteract RAS/MAPK-induced differentiation. Furthermore, cross-talk between the NOTCH and hypoxia-response pathways modulates the capability of the VPCs to respond to RAS/MAPK signaling. Lateral NOTCH signaling positively regulates the prolyl hydroxylase EGL-9, which promotes HIF-1 degradation in uncommitted VPCs and permits RAS/MAPK-induced differentiation. By inducing DELTA family NOTCH ligands, RAS/MAPK signaling creates a positive feedback loop that represses HIF-1 and NHR-57 expression in the proximal VPCs and keeps them capable of differentiating. This regulatory network formed by the NOTCH, hypoxia, and RAS/MAPK pathways may allow the animals to adapt developmental processes to variations in oxygen concentration.
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Affiliation(s)
- Sabrina Maxeiner
- Institute of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
- PhD Program in Molecular Life Sciences, University and ETH Zurich, Zurich, Switzerland
| | - Judith Grolleman
- Laboratory of Nematology, Wageningen University, Wageningen, The Netherlands
| | - Tobias Schmid
- Institute of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Jan Kammenga
- Laboratory of Nematology, Wageningen University, Wageningen, The Netherlands
| | - Alex Hajnal
- Institute of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
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7
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Shin H, Braendle C, Monahan KB, Kaplan REW, Zand TP, Mote FS, Peters EC, Reiner DJ. Developmental fidelity is imposed by genetically separable RalGEF activities that mediate opposing signals. PLoS Genet 2019; 15:e1008056. [PMID: 31086367 PMCID: PMC6534338 DOI: 10.1371/journal.pgen.1008056] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 05/24/2019] [Accepted: 02/28/2019] [Indexed: 02/06/2023] Open
Abstract
The six C. elegans vulval precursor cells (VPCs) are induced to form the 3°-3°-2°-1°-2°-3° pattern of cell fates with high fidelity. In response to EGF signal, the LET-60/Ras-LIN-45/Raf-MEK-2/MEK-MPK-1/ERK canonical MAP kinase cascade is necessary to induce 1° fate and synthesis of DSL ligands for the lateral Notch signal. In turn, LIN-12/Notch receptor is necessary to induce neighboring cells to become 2°. We previously showed that, in response to graded EGF signal, the modulatory LET-60/Ras-RGL-1/RalGEF-RAL-1/Ral signal promotes 2° fate in support of LIN-12. In this study, we identify two key differences between RGL-1 and RAL-1. First, deletion of RGL-1 confers no overt developmental defects, while previous studies showed RAL-1 to be essential for viability and fertility. From this observation, we hypothesize that the essential functions of RAL-1 are independent of upstream activation. Second, RGL-1 plays opposing and genetically separable roles in VPC fate patterning. RGL-1 promotes 2° fate via canonical GEF-dependent activation of RAL-1. Conversely, RGL-1 promotes 1° fate via a non-canonical GEF-independent activity. Our genetic epistasis experiments are consistent with RGL-1 functioning in the modulatory 1°-promoting AGE-1/PI3-Kinase-PDK-1-AKT-1 cascade. Additionally, animals lacking RGL-1 experience 15-fold higher rates of VPC patterning errors compared to the wild type. Yet VPC patterning in RGL-1 deletion mutants is not more sensitive to environmental perturbations. We propose that RGL-1 functions to orchestrate opposing 1°- and 2°-promoting modulatory cascades to decrease developmental stochasticity. We speculate that such switches are broadly conserved but mostly masked by paralog redundancy or essential functions. Developmental signals are increasingly conceptualized in the context of networks rather than linear pathways. Patterning of C. elegans vulval fates is mostly governed by two major signaling cascades that operate antagonistically to induce two cell identities. An additional pair of minor cascades support each of the major cascades. All components in this system are conserved in mammalian oncogenic signaling networks. We find that RGL-1, a component of one of the minor cascades, performs two antagonistic functions. Its deletion appears to abolish both opposing modulatory signals, resulting in a 15-fold increase in the basal error rate in development of these cells. We hypothesize that the bifunctional RGL-1 protein defines a novel mechanism by which signaling networks are interwoven to mitigate developmental errors.
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Affiliation(s)
- Hanna Shin
- Institute of Biosciences and Technology, Texas A&M Health Science Center, Texas A&M University, Houston, TX, United States of America
| | | | - Kimberly B Monahan
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC, United States of America
| | - Rebecca E W Kaplan
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC, United States of America
| | - Tanya P Zand
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC, United States of America.,Department of Pharmacology, University of North Carolina, Chapel Hill, NC, United States of America
| | - Francisca Sefakor Mote
- Institute of Biosciences and Technology, Texas A&M Health Science Center, Texas A&M University, Houston, TX, United States of America
| | - Eldon C Peters
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC, United States of America
| | - David J Reiner
- Institute of Biosciences and Technology, Texas A&M Health Science Center, Texas A&M University, Houston, TX, United States of America.,Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC, United States of America.,Department of Pharmacology, University of North Carolina, Chapel Hill, NC, United States of America
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8
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Shin H, Reiner DJ. The Signaling Network Controlling C. elegans Vulval Cell Fate Patterning. J Dev Biol 2018; 6:E30. [PMID: 30544993 PMCID: PMC6316802 DOI: 10.3390/jdb6040030] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 12/08/2018] [Accepted: 12/10/2018] [Indexed: 12/17/2022] Open
Abstract
EGF, emitted by the Anchor Cell, patterns six equipotent C. elegans vulval precursor cells to assume a precise array of three cell fates with high fidelity. A group of core and modulatory signaling cascades forms a signaling network that demonstrates plasticity during the transition from naïve to terminally differentiated cells. In this review, we summarize the history of classical developmental manipulations and molecular genetics experiments that led to our understanding of the signals governing this process, and discuss principles of signal transduction and developmental biology that have emerged from these studies.
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Affiliation(s)
- Hanna Shin
- Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX 77030, USA.
| | - David J Reiner
- Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX 77030, USA.
- College of Medicine, Texas A & M University, Houston, TX 77030, USA.
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9
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Rasmussen NR, Dickinson DJ, Reiner DJ. Ras-Dependent Cell Fate Decisions Are Reinforced by the RAP-1 Small GTPase in Caenorhabditiselegans. Genetics 2018; 210:1339-1354. [PMID: 30257933 PMCID: PMC6283165 DOI: 10.1534/genetics.118.301601] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 09/15/2018] [Indexed: 12/15/2022] Open
Abstract
The notoriety of the small GTPase Ras as the most mutated oncoprotein has led to a well-characterized signaling network largely conserved across metazoans. Yet the role of its close relative Rap1 (Ras Proximal), which shares 100% identity between their core effector binding sequences, remains unclear. A long-standing controversy in the field is whether Rap1 also functions to activate the canonical Ras effector, the S/T kinase Raf. We used the developmentally simpler Caenorhabditis elegans, which lacks the extensive paralog redundancy of vertebrates, to examine the role of RAP-1 in two distinct LET-60/Ras-dependent cell fate patterning events: induction of 1° vulval precursor cell (VPC) fate and of the excretory duct cell. Fluorescence-tagged endogenous RAP-1 is localized to plasma membranes and is expressed ubiquitously, with even expression levels across the VPCs. RAP-1 and its activating GEF PXF-1 function cell autonomously and are necessary for maximal induction of 1° VPCs. Critically, mutationally activated endogenous RAP-1 is sufficient both to induce ectopic 1°s and duplicate excretory duct cells. Like endogenous RAP-1, before induction GFP expression from the pxf-1 promoter is uniform across VPCs. However, unlike endogenous RAP-1, after induction GFP expression is increased in presumptive 1°s and decreased in presumptive 2°s. We conclude that RAP-1 is a positive regulator that promotes Ras-dependent inductive fate decisions. We hypothesize that PXF-1 activation of RAP-1 serves as a minor parallel input into the major LET-60/Ras signal through LIN-45/Raf.
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Affiliation(s)
- Neal R Rasmussen
- Institute of Biosciences and Technology, College of Medicine, Texas A&M University, Houston, Texas 77030
| | - Daniel J Dickinson
- Department of Molecular Biosciences, University of Texas, Austin, Texas 78705
| | - David J Reiner
- Institute of Biosciences and Technology, College of Medicine, Texas A&M University, Houston, Texas 77030
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10
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Sala M, Spensiero A, Scala MC, Pepe G, Bilotta A, Paduano F, D'Agostino S, Lanzillotta D, Bertamino A, Novellino E, Trapasso F, Gomez-Monterrey IM, Campiglia P. Design, Synthesis, Biological Activity, and Structural Analysis of Lactam-Constrained PTPRJ Agonist Peptides. ChemMedChem 2018; 13:1673-1680. [PMID: 29888867 DOI: 10.1002/cmdc.201800147] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 05/25/2018] [Indexed: 01/13/2023]
Abstract
PTPRJ is a receptor-like protein tyrosine phosphatase mainly known for its antiproliferative and tumor-suppressive functions. PTPRJ dephosphorylates several growth factors and their receptors, negatively regulating cell proliferation and migration. We recently identified a disulfide-bridged nonapeptide, named PTPRJ-19 (H-[Cys-His-His-Asn-Leu-Thr-His-Ala-Cys]-OH), which activates PTPRJ, thereby causing cell growth inhibition and apoptosis of both cancer and endothelial cells. With the aim of replacing the disulfide bridge by a chemically more stable moiety, we have synthesized and tested a series of lactam analogues of PTPRJ-19. This replacement led to analogues with higher activity and greater stability than the parent peptide.
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Affiliation(s)
- Marina Sala
- Department of Pharmacy, University of Salerno, 84084, Fisciano (SA), Italy
| | - Antonia Spensiero
- Department of Pharmacy, University of Salerno, 84084, Fisciano (SA), Italy
| | | | - Giacomo Pepe
- Department of Pharmacy, University of Salerno, 84084, Fisciano (SA), Italy
| | - Anna Bilotta
- Department of Medicina Sperimentale e Clinica, University Magna Graecia, Campus "S. Venuta", 88100, Catanzaro, Italy
| | - Francesco Paduano
- Department of Medicina Sperimentale e Clinica, University Magna Graecia, Campus "S. Venuta", 88100, Catanzaro, Italy
| | - Sabrina D'Agostino
- Department of Medicina Sperimentale e Clinica, University Magna Graecia, Campus "S. Venuta", 88100, Catanzaro, Italy
| | - Delia Lanzillotta
- Department of Medicina Sperimentale e Clinica, University Magna Graecia, Campus "S. Venuta", 88100, Catanzaro, Italy
| | - Alessia Bertamino
- Department of Pharmacy, University of Salerno, 84084, Fisciano (SA), Italy
| | - Ettore Novellino
- Department of Pharmacy, University of Naples "Federico II", 80131, Naples, Italy
| | - Francesco Trapasso
- Department of Medicina Sperimentale e Clinica, University Magna Graecia, Campus "S. Venuta", 88100, Catanzaro, Italy
| | | | - Pietro Campiglia
- Department of Pharmacy, University of Salerno, 84084, Fisciano (SA), Italy
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11
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The receptor protein tyrosine phosphatase PTPRJ negatively modulates the CD98hc oncoprotein in lung cancer cells. Oncotarget 2018; 9:23334-23348. [PMID: 29805737 PMCID: PMC5955124 DOI: 10.18632/oncotarget.25101] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 03/24/2018] [Indexed: 01/16/2023] Open
Abstract
PTPRJ, a receptor protein tyrosine phosphatase strongly downregulated in human cancer, displays tumor suppressor activity by negatively modulating several proteins involved in proliferating signals. Here, through a proteomic-based approach, we identified a list of potential PTPRJ-interacting proteins and among them we focused on CD98hc, a type II glycosylated integral membrane protein encoded by SLC3A2, corresponding to the heavy chain of a heterodimeric transmembrane amino-acid transporter, including LAT1. CD98hc is widely overexpressed in several types of cancers and contributes to the process of tumorigenesis by interfering with cell proliferation, adhesion, and migration. We first validated PTPRJ-CD98hc interaction, then demonstrated that PTPRJ overexpression dramatically reduces CD98hc protein levels in A549 lung cancer cells. In addition, following to the treatment of PTPRJ-transduced cells with MG132, a proteasome inhibitor, CD98hc levels did not decrease compared to controls, indicating that PTPRJ is involved in the regulation of CD98hc proteasomal degradation. Moreover, PTPRJ overexpression combined with CD98hc silencing consistently reduced cell proliferation and triggered apoptosis of lung cancer cells. Interestingly, by interrogating the can Evolve database, we observed an inverse correlation between PTPRJ and SLC3A2 gene expression. Indeed, the non-small cell lung cancers (NSCLCs) of patients showing a short survival rate express the lowest and the highest levels of PTPRJ and SLC3A2, respectively. Therefore, the results reported here contribute to shed lights on PTPRJ signaling in cancer cells: moreover, our findings also support the development of a novel anticancer therapeutic approach by targeting the pathway of PTPRJ that is usually downregulated in highly malignant human neoplasias.
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12
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Bilotta A, Dattilo V, D'Agostino S, Belviso S, Scalise S, Bilotta M, Gaudio E, Paduano F, Perrotti N, Florio T, Fusco A, Iuliano R, Trapasso F. A novel splice variant of the protein tyrosine phosphatase PTPRJ that encodes for a soluble protein involved in angiogenesis. Oncotarget 2018; 8:10091-10102. [PMID: 28052032 PMCID: PMC5354644 DOI: 10.18632/oncotarget.14350] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Accepted: 12/13/2016] [Indexed: 02/01/2023] Open
Abstract
PTPRJ is a receptor protein tyrosine phosphatase with tumor suppressor activity. Very little is known about the role of PTPRJ ectodomain, although recently both physiological and synthetic PTPRJ ligands have been identified. A putative shorter spliced variant, coding for a 539 aa protein corresponding to the extracellular N-terminus of PTPRJ, is reported in several databases but, currently, no further information is available. Here, we confirmed that the PTPRJ short isoform (named sPTPRJ) is a soluble protein secreted into the supernatant of both endothelial and tumor cells. Like PTPRJ, also sPTPRJ undergoes post-translational modifications such as glycosylation, as assessed by sPTPRJ immunoprecipitation. To characterize its functional activity, we performed an endothelial cell tube formation assay and a wound healing assay on HUVEC cells overexpressing sPTPRJ and we found that sPTPRJ has a proangiogenic activity. We also showed that sPTPRJ expression down-regulates endothelial adhesion molecules, that is a hallmark of proangiogenic activity. Moreover, sPTPRJ mRNA levels in human high-grade glioma, one of the most angiogenic tumors, are higher in tumor samples compared to controls. Further studies will be helpful not only to clarify the way sPTPRJ works but also to supply clues to circumvent its activity in cancer therapy.
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Affiliation(s)
- Anna Bilotta
- Department of Medicina Sperimentale e Clinica, University Magna Graecia of Catanzaro, Catanzaro, Italy
| | - Vincenzo Dattilo
- Department of Scienze della Salute, University Magna Graecia of Catanzaro, Catanzaro, Italy
| | - Sabrina D'Agostino
- Department of Medicina Sperimentale e Clinica, University Magna Graecia of Catanzaro, Catanzaro, Italy
| | - Stefania Belviso
- Department of Medicina Sperimentale e Clinica, University Magna Graecia of Catanzaro, Catanzaro, Italy
| | - Stefania Scalise
- Department of Medicina Sperimentale e Clinica, University Magna Graecia of Catanzaro, Catanzaro, Italy
| | - Mariaconcetta Bilotta
- Department of Medicina Sperimentale e Clinica, University Magna Graecia of Catanzaro, Catanzaro, Italy
| | - Eugenio Gaudio
- Department of Medicina Sperimentale e Clinica, University Magna Graecia of Catanzaro, Catanzaro, Italy.,Lymphoma and Genomics Research Program, Institute of Oncology Research (IOR), Bellinzona, Switzerland
| | - Francesco Paduano
- Department of Medicina Sperimentale e Clinica, University Magna Graecia of Catanzaro, Catanzaro, Italy.,Tecnologica Research Institute, Biomedical Section, Crotone, Italy
| | - Nicola Perrotti
- Department of Scienze della Salute, University Magna Graecia of Catanzaro, Catanzaro, Italy
| | - Tullio Florio
- Laboratory of Pharmacology, Dept. of Internal Medicine, and Center of Excellence for Biomedical Research (CEBR), University of Genova, Genova, Italy
| | - Alfredo Fusco
- Istituto di Endocrinologia e Oncologia Sperimentale - CNR c/o Dipartimento di Medicina Molecolare e Biotecnologie Mediche, University Federico II of Napoli, Napoli, Italy
| | - Rodolfo Iuliano
- Department of Medicina Sperimentale e Clinica, University Magna Graecia of Catanzaro, Catanzaro, Italy
| | - Francesco Trapasso
- Department of Medicina Sperimentale e Clinica, University Magna Graecia of Catanzaro, Catanzaro, Italy
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13
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Meeusen B, Janssens V. Tumor suppressive protein phosphatases in human cancer: Emerging targets for therapeutic intervention and tumor stratification. Int J Biochem Cell Biol 2017; 96:98-134. [PMID: 29031806 DOI: 10.1016/j.biocel.2017.10.002] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2017] [Revised: 10/04/2017] [Accepted: 10/05/2017] [Indexed: 02/06/2023]
Abstract
Aberrant protein phosphorylation is one of the hallmarks of cancer cells, and in many cases a prerequisite to sustain tumor development and progression. Like protein kinases, protein phosphatases are key regulators of cell signaling. However, their contribution to aberrant signaling in cancer cells is overall less well appreciated, and therefore, their clinical potential remains largely unexploited. In this review, we provide an overview of tumor suppressive protein phosphatases in human cancer. Along their mechanisms of inactivation in defined cancer contexts, we give an overview of their functional roles in diverse signaling pathways that contribute to their tumor suppressive abilities. Finally, we discuss their emerging roles as predictive or prognostic markers, their potential as synthetic lethality targets, and the current feasibility of their reactivation with pharmacologic compounds as promising new cancer therapies. We conclude that their inclusion in clinical practice has obvious potential to significantly improve therapeutic outcome in various ways, and should now definitely be pushed forward.
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Affiliation(s)
- Bob Meeusen
- Laboratory of Protein Phosphorylation & Proteomics, Dept. of Cellular & Molecular Medicine, Faculty of Medicine, KU Leuven & Leuven Cancer Institute (LKI), KU Leuven, Belgium
| | - Veerle Janssens
- Laboratory of Protein Phosphorylation & Proteomics, Dept. of Cellular & Molecular Medicine, Faculty of Medicine, KU Leuven & Leuven Cancer Institute (LKI), KU Leuven, Belgium.
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14
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de la Cova C, Townley R, Regot S, Greenwald I. A Real-Time Biosensor for ERK Activity Reveals Signaling Dynamics during C. elegans Cell Fate Specification. Dev Cell 2017; 42:542-553.e4. [PMID: 28826819 PMCID: PMC5595649 DOI: 10.1016/j.devcel.2017.07.014] [Citation(s) in RCA: 92] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 06/19/2017] [Accepted: 07/20/2017] [Indexed: 01/06/2023]
Abstract
Kinase translocation reporters (KTRs) are genetically encoded fluorescent activity sensors that convert kinase activity into a nucleocytoplasmic shuttling equilibrium for visualizing single-cell signaling dynamics. Here, we adapt the first-generation KTR for extracellular signal-regulated kinase (ERK) to allow easy implementation in vivo. This sensor, "ERK-nKTR," allows quantitative and qualitative assessment of ERK activity by analysis of individual nuclei and faithfully reports ERK activity during development and neural function in diverse cell contexts in Caenorhabditis elegans. Analysis of ERK activity over time in the vulval precursor cells, a well-characterized paradigm of epidermal growth factor receptor (EGFR)-Ras-ERK signaling, has identified dynamic features not evident from analysis of developmental endpoints alone, including pulsatile frequency-modulated signaling associated with proximity to the EGF source. The toolkit described here will facilitate studies of ERK signaling in other C. elegans contexts, and the design features will enable implementation of this technology in other multicellular organisms.
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Affiliation(s)
- Claire de la Cova
- Department of Biological Sciences, Columbia University, New York, NY, USA; Department of Biochemistry & Molecular Biophysics, Columbia University Medical Center, New York, NY, USA
| | - Robert Townley
- Department of Biological Sciences, Columbia University, New York, NY, USA
| | - Sergi Regot
- Department of Molecular Biology & Genetics, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
| | - Iva Greenwald
- Department of Biological Sciences, Columbia University, New York, NY, USA; Department of Biochemistry & Molecular Biophysics, Columbia University Medical Center, New York, NY, USA.
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15
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Chicote JU, DeSalle R, García-España A. Phosphotyrosine phosphatase R3 receptors: Origin, evolution and structural diversification. PLoS One 2017; 12:e0172887. [PMID: 28257417 PMCID: PMC5336234 DOI: 10.1371/journal.pone.0172887] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Accepted: 02/10/2017] [Indexed: 11/18/2022] Open
Abstract
Subtype R3 phosphotyrosine phosphatase receptors (R3 RPTPs) are single-spanning membrane proteins characterized by a unique modular composition of extracellular fibronectin repeats and a single cytoplasmatic protein tyrosine phosphatase (PTP) domain. Vertebrate R3 RPTPs consist of five members: PTPRB, PTPRJ, PTPRH and PTPRO, which dephosphorylate tyrosine residues, and PTPRQ, which dephosphorylates phophoinositides. R3 RPTPs are considered novel therapeutic targets in several pathologies such as ear diseases, nephrotic syndromes and cancer. R3 RPTP vertebrate receptors, as well as their known invertebrate counterparts from animal models: PTP52F, PTP10D and PTP4e from the fruitfly Drosophila melanogaster and F44G4.8/DEP-1 from the nematode Caenorhabditis elegans, participate in the regulation of cellular activities including cell growth and differentiation. Despite sharing structural and functional properties, the evolutionary relationships between vertebrate and invertebrate R3 RPTPs are not fully understood. Here we gathered R3 RPTPs from organisms covering a broad evolutionary distance, annotated their structure and analyzed their phylogenetic relationships. We show that R3 RPTPs (i) have probably originated in the common ancestor of animals (metazoans), (ii) are variants of a single ancestral gene in protostomes (arthropods, annelids and nematodes); (iii) a likely duplication of this ancestral gene in invertebrate deuterostomes (echinodermes, hemichordates and tunicates) generated the precursors of PTPRQ and PTPRB genes, and (iv) R3 RPTP groups are monophyletic in vertebrates and have specific conserved structural characteristics. These findings could have implications for the interpretation of past studies and provide a framework for future studies and functional analysis of this important family of proteins.
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Affiliation(s)
- Javier U. Chicote
- Hospital Universitari de Tarragona Joan XXIII, Institut d’Investigació Sanitària Pere Virgili, Universitat Rovira i Virgili, Tarragona, Spain
| | - Rob DeSalle
- Sackler Institute for Comparative Genomics, American Museum of Natural History, New York, NewYork, United States of America
| | - Antonio García-España
- Hospital Universitari de Tarragona Joan XXIII, Institut d’Investigació Sanitària Pere Virgili, Universitat Rovira i Virgili, Tarragona, Spain
- * E-mail:
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16
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Gauthier K, Rocheleau CE. C. elegans Vulva Induction: An In Vivo Model to Study Epidermal Growth Factor Receptor Signaling and Trafficking. Methods Mol Biol 2017; 1652:43-61. [PMID: 28791633 DOI: 10.1007/978-1-4939-7219-7_3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Epidermal growth factor receptor (EGFR)-mediated activation of the canonical Ras/MAPK signaling cascade is responsible for cell proliferation and cell growth. This signaling pathway is frequently overactivated in epithelial cancers; therefore, studying regulation of this pathway is crucial not only for our fundamental understanding of cell biology but also for our ability to treat EGFR-related disease. Genetic model organisms such as Caenorhabditis elegans, a hermaphroditic nematode, played a vital role in identifying components of the EGFR/Ras/MAPK pathway and delineating their order of function, and continues to play a role in identifying novel regulators of the pathway. Polarized activation of LET-23, the C. elegans homolog of EGFR, is responsible for induction of the vulval cell fate; perturbations in this signaling pathway produce either a vulvaless or multivulva phenotype. The translucent cuticle of the nematode facilitates in vivo visualization of the receptor, revealing that localization of LET-23 EGFR is tightly regulated and linked to its function. In this chapter, we review the methods used to harness vulva development as a tool for studying EGFR signaling and trafficking in C. elegans.
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Affiliation(s)
- Kimberley Gauthier
- Department of Anatomy and Cell Biology, McGill University, Montreal, Canada
- Centre for Translational Biology, Research Institute of the McGill University Health Centre, Montreal, Canada
| | - Christian E Rocheleau
- Department of Anatomy and Cell Biology, McGill University, Montreal, Canada.
- Centre for Translational Biology, Research Institute of the McGill University Health Centre, Montreal, Canada.
- Division of Endocrinology and Metabolism, Department of Medicine, McGill University, Montreal, Canada.
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17
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Walser M, Umbricht CA, Fröhli E, Nanni P, Hajnal A. β-Integrin de-phosphorylation by the Density-Enhanced Phosphatase DEP-1 attenuates EGFR signaling in C. elegans. PLoS Genet 2017; 13:e1006592. [PMID: 28135265 PMCID: PMC5305270 DOI: 10.1371/journal.pgen.1006592] [Citation(s) in RCA: 10] [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: 08/30/2016] [Revised: 02/13/2017] [Accepted: 01/20/2017] [Indexed: 11/19/2022] Open
Abstract
Density-Enhanced Phosphatase-1 (DEP-1) de-phosphorylates various growth factor receptors and adhesion proteins to regulate cell proliferation, adhesion and migration. Moreover, dep-1/scc1 mutations have been detected in various types of human cancers, indicating a broad tumor suppressor activity. During C. elegans development, DEP-1 mediates binary cell fate decisions by negatively regulating EGFR signaling. Using a substrate-trapping DEP-1 mutant in a proteomics approach, we have identified the C. elegans β-integrin subunit PAT-3 as a specific DEP-1 substrate. DEP-1 selectively de-phosphorylates tyrosine 792 in the membrane-proximal NPXY motif to promote integrin activation via talin recruitment. The non-phosphorylatable β-integrin mutant pat-3(Y792F) partially suppresses the hyperactive EGFR signaling phenotype caused by loss of dep-1 function. Thus, DEP-1 attenuates EGFR signaling in part by de-phosphorylating Y792 in the β-integrin cytoplasmic tail, besides the direct de-phosphorylation of the EGFR. Furthermore, in vivo FRAP analysis indicates that the αβ-integrin/talin complex attenuates EGFR signaling by restricting receptor mobility on the basolateral plasma membrane. We propose that DEP-1 regulates EGFR signaling via two parallel mechanisms, by direct receptor de-phosphorylation and by restricting receptor mobility through αβ-integrin activation.
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Affiliation(s)
- Michael Walser
- Institute of Molecular Life Sciences, University of Zürich, Winterthurerstr. 190, University of Zürich, Zürich, Switzerland
- Molecular Life Science Zürich PhD program, Zürich, Switzerland
| | - Christoph Alois Umbricht
- Institute of Molecular Life Sciences, University of Zürich, Winterthurerstr. 190, University of Zürich, Zürich, Switzerland
| | - Erika Fröhli
- Institute of Molecular Life Sciences, University of Zürich, Winterthurerstr. 190, University of Zürich, Zürich, Switzerland
| | - Paolo Nanni
- Functional Genomics Center Zürich, University of Zürich/ETH Zürich, Winterthurerstr. 190, Zürich, Switzerland
| | - Alex Hajnal
- Institute of Molecular Life Sciences, University of Zürich, Winterthurerstr. 190, University of Zürich, Zürich, Switzerland
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18
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Lussi YC, Mariani L, Friis C, Peltonen J, Myers TR, Krag C, Wong G, Salcini AE. Impaired removal of H3K4 methylation affects cell fate determination and gene transcription. Development 2016; 143:3751-3762. [PMID: 27578789 DOI: 10.1242/dev.139139] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Accepted: 08/20/2016] [Indexed: 01/30/2023]
Abstract
Methylation of histone 3 lysine 4 (H3K4) is largely associated with promoters and enhancers of actively transcribed genes and is finely regulated during development by the action of histone methyltransferases and demethylases. H3K4me3 demethylases of the KDM5 family have been previously implicated in development, but how the regulation of H3K4me3 level controls developmental processes is not fully established. Here, we show that the H3K4 demethylase RBR-2, the unique member of the KDM5 family in C. elegans, acts cell-autonomously and in a catalytic-dependent manner to control vulva precursor cells fate acquisition, by promoting the LIN-12/Notch pathway. Using genome-wide approaches, we show that RBR-2 reduces the H3K4me3 level at transcription start sites (TSSs) and in regions upstream of the TSSs, and acts both as a transcription repressor and activator. Analysis of the lin-11 genetic locus, a direct RBR-2 target gene required for vulva precursor cell fate acquisition, shows that RBR-2 controls the epigenetic signature of the lin-11 vulva-specific enhancer and lin-11 expression, providing in vivo evidence that RBR-2 can positively regulate transcription and cell fate acquisition by controlling enhancer activity.
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Affiliation(s)
- Yvonne C Lussi
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen DK-2200, Denmark.,Centre for Epigenetics, University of Copenhagen, Copenhagen DK-2200, Denmark
| | - Luca Mariani
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen DK-2200, Denmark.,Centre for Epigenetics, University of Copenhagen, Copenhagen DK-2200, Denmark
| | - Carsten Friis
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen DK-2200, Denmark.,Centre for Epigenetics, University of Copenhagen, Copenhagen DK-2200, Denmark
| | - Juhani Peltonen
- A. I. Virtanen Institute for Molecular Sciences, Department of Neurobiology, University of Eastern Finland, Kuopio 70211, Finland
| | - Toshia R Myers
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen DK-2200, Denmark.,Centre for Epigenetics, University of Copenhagen, Copenhagen DK-2200, Denmark
| | - Claudia Krag
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen DK-2200, Denmark
| | - Garry Wong
- A. I. Virtanen Institute for Molecular Sciences, Department of Neurobiology, University of Eastern Finland, Kuopio 70211, Finland
| | - Anna Elisabetta Salcini
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen DK-2200, Denmark .,Centre for Epigenetics, University of Copenhagen, Copenhagen DK-2200, Denmark
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19
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Flibotte S, Kim BR, Van de Laar E, Brown L, Moghal N. The SWI/SNF chromatin remodeling complex exerts both negative and positive control over LET-23/EGFR-dependent vulval induction in Caenorhabditis elegans. Dev Biol 2016; 415:46-63. [PMID: 27207389 DOI: 10.1016/j.ydbio.2016.05.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Revised: 05/05/2016] [Accepted: 05/09/2016] [Indexed: 11/19/2022]
Abstract
Signaling by the epidermal growth factor receptor (EGFR) generates diverse developmental patterns. This requires precise control over the location and intensity of signaling. Elucidation of these regulatory mechanisms is important for understanding development and disease pathogenesis. In Caenorhabditis elegans, LIN-3/EGF induces vulval formation in the mid-body, which requires LET-23/EGFR activation only in P6.p, the vulval progenitor nearest the LIN-3 source. To identify mechanisms regulating this signaling pattern, we screened for mutations that cooperate with a let-23 gain-of-function allele to cause ectopic vulval induction. Here, we describe a dominant gain-of-function mutation in swsn-4, a component of SWI/SNF chromatin remodeling complexes. Loss-of-function mutations in multiple SWI/SNF components reveal that weak reduction in SWI/SNF activity causes ectopic vulval induction, while stronger reduction prevents adoption of vulval fates, a phenomenon also observed with increasing loss of LET-23 activity. High levels of LET-23 expression in P6.p are thought to locally sequester LIN-3, thereby preventing ectopic vulval induction, with slight reductions in its expression interfering with LIN-3 sequestration, but not vulval fate signaling. We find that SWI/SNF positively regulates LET-23 expression in P6.p descendants, providing an explanation for the similarities between let-23 and SWI/SNF mutant phenotypes. However, SWI/SNF regulation of LET-23 expression is cell-specific, with SWI/SNF repressing its expression in the ALA neuron. The swsn-4 gain-of-function mutation affects the PTH domain, and provides the first evidence that its auto-inhibitory function in yeast Sth1p is conserved in metazoan chromatin remodelers. Finally, our work supports broad use of SWI/SNF in regulating EGFR signaling during development, and suggests that dominant SWI/SNF mutations in certain human congenital anomaly syndromes may be gain-of-functions.
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Affiliation(s)
- Stephane Flibotte
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z4.
| | - Bo Ram Kim
- Princess Margaret Cancer Centre/University Health Network, Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada M5G 1L7.
| | - Emily Van de Laar
- Princess Margaret Cancer Centre/University Health Network, Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada M5G 1L7.
| | - Louise Brown
- Samuel Lunenfeld Research Institute of Mount Sinai Hospital, Toronto, Ontario, Canada M5G 1X5.
| | - Nadeem Moghal
- Princess Margaret Cancer Centre/University Health Network, Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada M5G 1L7.
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20
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Asbagh LA, Vazquez I, Vecchione L, Budinska E, De Vriendt V, Baietti MF, Steklov M, Jacobs B, Hoe N, Singh S, Imjeti NS, Zimmermann P, Sablina A, Tejpar S. The tyrosine phosphatase PTPRO sensitizes colon cancer cells to anti-EGFR therapy through activation of SRC-mediated EGFR signaling. Oncotarget 2015; 5:10070-83. [PMID: 25301722 PMCID: PMC4259406 DOI: 10.18632/oncotarget.2458] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Inappropriate activation of epidermal growth factor receptor (EGFR) plays a causal role in many cancers including colon cancer. The activation of EGFR by phosphorylation is balanced by receptor kinase and protein tyrosine phosphatase activities. However, the mechanisms of negative EGFR regulation by tyrosine phosphatases remain largely unexplored. Our previous results indicate that protein tyrosine phosphatase receptor type O (PTPRO) is down-regulated in a subset of colorectal cancer (CRC) patients with a poor prognosis. Here we identified PTPRO as a phosphatase that negatively regulates SRC by directly dephosphorylating Y416 phosphorylation site. SRC activation triggered by PTPRO down-regulation induces phosphorylation of both EGFR at Y845 and the c-CBL ubiquitin ligase at Y731. Increased EGFR phosphorylation at Y845 promotes its receptor activity, whereas enhanced phosphorylation of c-CBL triggers its degradation promoting EGFR stability. Importantly, hyperactivation of SRC/EGFR signaling triggered by loss of PTPRO leads to high resistance of colon cancer to EGFR inhibitors. Our results not only highlight the PTPRO contribution in negative regulation of SRC/EGFR signaling but also suggest that tumors with low PTPRO expression may be therapeutically targetable by anti-SRC therapies.
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Affiliation(s)
- Layka Abbasi Asbagh
- Laboratory of Molecular Digestive Oncology, Department of Oncology, KU Leuven, Leuven, Belgium. Laboratory for Mechanisms of Cell Transformation, VIB Center for the Biology of Disease, VIB, Belgium. Center for Human Genetics, KU Leuven, Leuven, Belgium
| | - Iria Vazquez
- Laboratory for Mechanisms of Cell Transformation, VIB Center for the Biology of Disease, VIB, Belgium. Center for Human Genetics, KU Leuven, Leuven, Belgium
| | - Loredana Vecchione
- Laboratory of Molecular Digestive Oncology, Department of Oncology, KU Leuven, Leuven, Belgium
| | - Eva Budinska
- Institute of Biostatistics and Analyses, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Veerle De Vriendt
- Laboratory of Molecular Digestive Oncology, Department of Oncology, KU Leuven, Leuven, Belgium
| | - Maria Francesca Baietti
- Laboratory for Mechanisms of Cell Transformation, VIB Center for the Biology of Disease, VIB, Belgium. Center for Human Genetics, KU Leuven, Leuven, Belgium
| | - Mikhail Steklov
- Laboratory for Mechanisms of Cell Transformation, VIB Center for the Biology of Disease, VIB, Belgium. Center for Human Genetics, KU Leuven, Leuven, Belgium
| | - Bart Jacobs
- Laboratory of Molecular Digestive Oncology, Department of Oncology, KU Leuven, Leuven, Belgium
| | | | | | - Naga-Sailaja Imjeti
- Centre de Recherche en Cancérologie de Marseille (CRCM), Inserm, U1068-CNRS UMR7258, Aix-Marseille Université, Institut Paoli-Calmettes, Marseille, France. Center for Human Genetics, KU Leuven, Leuven, Belgium
| | - Pascale Zimmermann
- Centre de Recherche en Cancérologie de Marseille (CRCM), Inserm, U1068-CNRS UMR7258, Aix-Marseille Université, Institut Paoli-Calmettes, Marseille, France. Center for Human Genetics, KU Leuven, Leuven, Belgium
| | - Anna Sablina
- Laboratory for Mechanisms of Cell Transformation, VIB Center for the Biology of Disease, VIB, Belgium. Center for Human Genetics, KU Leuven, Leuven, Belgium
| | - Sabine Tejpar
- Laboratory of Molecular Digestive Oncology, Department of Oncology, KU Leuven, Leuven, Belgium
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21
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Schmid T, Hajnal A. Signal transduction during C. elegans vulval development: a NeverEnding story. Curr Opin Genet Dev 2015; 32:1-9. [DOI: 10.1016/j.gde.2015.01.006] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Revised: 01/19/2015] [Accepted: 01/21/2015] [Indexed: 11/16/2022]
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22
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Fares MA. The origins of mutational robustness. Trends Genet 2015; 31:373-81. [PMID: 26013677 DOI: 10.1016/j.tig.2015.04.008] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Revised: 04/27/2015] [Accepted: 04/28/2015] [Indexed: 11/17/2022]
Abstract
Biological systems are resistant to genetic changes; a property known as mutational robustness, the origin of which remains an open question. In recent years, researchers have explored emergent properties of biological systems and mechanisms of genetic redundancy to reveal how mutational robustness emerges and persists. Several mechanisms have been proposed to explain the origin of mutational robustness, including molecular chaperones and gene duplication. The latter has received much attention, but its role in robustness remains controversial. Here, I examine recent findings linking genetic redundancy through gene duplication and mutational robustness. Experimental evolution and genome resequencing have made it possible to test the role of gene duplication in tolerating mutations at both the coding and regulatory levels. This evidence as well as previous findings on regulatory reprogramming of duplicates support the role of gene duplication in the origin of robustness.
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Affiliation(s)
- Mario A Fares
- Instituto de Biología Molecular y Celular de Plantas (CSIC-UPV), Valencia, Spain; Department of Genetics, Smurfit Institute of Genetics, University of Dublin, Trinity College Dublin, Dublin, Ireland.
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23
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Schmid T, Snoek LB, Fröhli E, van der Bent ML, Kammenga J, Hajnal A. Systemic Regulation of RAS/MAPK Signaling by the Serotonin Metabolite 5-HIAA. PLoS Genet 2015; 11:e1005236. [PMID: 25978500 PMCID: PMC4433219 DOI: 10.1371/journal.pgen.1005236] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Accepted: 04/23/2015] [Indexed: 11/18/2022] Open
Abstract
Human cancer is caused by the interplay of mutations in oncogenes and tumor suppressor genes and inherited variations in cancer susceptibility genes. While many of the tumor initiating mutations are well characterized, the effect of genetic background variation on disease onset and progression is less understood. We have used C. elegans genetics to identify genetic modifiers of the oncogenic RAS/MAPK signaling pathway. Quantitative trait locus analysis of two highly diverged C. elegans isolates combined with allele swapping experiments identified the polymorphic monoamine oxidase A (MAOA) gene amx-2 as a negative regulator of RAS/MAPK signaling. We further show that the serotonin metabolite 5-hydroxyindoleacetic acid (5-HIAA), which is a product of MAOA catalysis, systemically inhibits RAS/MAPK signaling in different organs of C. elegans. Thus, MAOA activity sets a global threshold for MAPK activation by controlling 5-HIAA levels. To our knowledge, 5-HIAA is the first endogenous small molecule that acts as a systemic inhibitor of RAS/MAPK signaling.
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Affiliation(s)
- Tobias Schmid
- University of Zurich, Institute of Molecular Life Sciences, Zurich, Switzerland
- PhD Program in Molecular Life Sciences, University and ETH Zurich, Zurich, Switzerland
| | - L. Basten Snoek
- Laboratory of Nematology, Wageningen University, Wageningen, The Netherlands
| | - Erika Fröhli
- University of Zurich, Institute of Molecular Life Sciences, Zurich, Switzerland
| | | | - Jan Kammenga
- Laboratory of Nematology, Wageningen University, Wageningen, The Netherlands
| | - Alex Hajnal
- University of Zurich, Institute of Molecular Life Sciences, Zurich, Switzerland
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24
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The protein tyrosine phosphatase DEP-1/PTPRJ promotes breast cancer cell invasion and metastasis. Oncogene 2015; 34:5536-47. [DOI: 10.1038/onc.2015.9] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Revised: 12/16/2014] [Accepted: 01/14/2015] [Indexed: 12/16/2022]
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25
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Hatzihristidis T, Desai N, Hutchins AP, Meng TC, Tremblay ML, Miranda-Saavedra D. A Drosophila-centric view of protein tyrosine phosphatases. FEBS Lett 2015; 589:951-66. [PMID: 25771859 DOI: 10.1016/j.febslet.2015.03.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Revised: 03/02/2015] [Accepted: 03/02/2015] [Indexed: 12/30/2022]
Abstract
Most of our knowledge on protein tyrosine phosphatases (PTPs) is derived from human pathologies and mouse knockout models. These models largely correlate well with human disease phenotypes, but can be ambiguous due to compensatory mechanisms introduced by paralogous genes. Here we present the analysis of the PTP complement of the fruit fly and the complementary view that PTP studies in Drosophila will accelerate our understanding of PTPs in physiological and pathological conditions. With only 44 PTP genes, Drosophila represents a streamlined version of the human complement. Our integrated analysis places the Drosophila PTPs into evolutionary and functional contexts, thereby providing a platform for the exploitation of the fly for PTP research and the transfer of knowledge onto other model systems.
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Affiliation(s)
- Teri Hatzihristidis
- Goodman Cancer Research Centre, McGill University, 1160 Pine Avenue, Montreal, Québec H3A 1A3, Canada; Department of Medicine, Division of Experimental Medicine, McGill University, Montreal, Quebec, Canada
| | - Nikita Desai
- Goodman Cancer Research Centre, McGill University, 1160 Pine Avenue, Montreal, Québec H3A 1A3, Canada; Department of Biochemistry, McGill University, Montreal, Quebec, Canada
| | - Andrew P Hutchins
- Key Laboratory of Regenerative Biology and Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, Guangdong 510530, China
| | - Tzu-Ching Meng
- Taiwan International Graduate Program, Academia Sinica, Taipei, Taiwan; Institute of Biochemical Sciences, National Taiwan University, Taipei, Taiwan; Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
| | - Michel L Tremblay
- Goodman Cancer Research Centre, McGill University, 1160 Pine Avenue, Montreal, Québec H3A 1A3, Canada; Department of Medicine, Division of Experimental Medicine, McGill University, Montreal, Quebec, Canada; Department of Biochemistry, McGill University, Montreal, Quebec, Canada.
| | - Diego Miranda-Saavedra
- World Premier International (WPI) Immunology Frontier Research Center (IFReC), Osaka University, 3-1 Yamadaoka, Suita 565-0871, Osaka, Japan; Centro de Biología Molecular Severo Ochoa, CSIC/Universidad Autónoma de Madrid, 28049 Madrid, Spain; IE Business School, IE University, María de Molina 31 bis, 28006 Madrid, Spain.
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26
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Reiner DJ. Ras effector switching as a developmental strategy. Small GTPases 2014; 2:109-112. [PMID: 21776412 DOI: 10.4161/sgtp.2.2.15775] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2011] [Accepted: 04/06/2011] [Indexed: 12/28/2022] Open
Abstract
Organisms pattern and specify cell fates with remarkably high fidelity and robustness, and cancer may be considered in part to be a disease of fate specification gone awry. During C. elegans vulval development an initial EGF signal prompts Ras to activate its canonical effector pathway, Raf-MEK-ERK, to induce a primary cell, which subsequently signals its 2 neighbors via Notch to develop as secondary cells. We have shown that Ras signaling through an alternate effector pathway, RalGEF-Ral, antagonizes Ras-Raf pro-primary signaling. Ras-RalGEF-Ral instead promotes secondary fate in support of Notch. We validated a previous model that EGF can also contribute to secondary fate, and argue that Ras-RalGEF-Ral mediates this EGF pro-secondary activity. Ras-Raf-MEK-ERK signaling was previously shown to be extinguished from secondary cells by secondary-specific expression of MAP kinase phosphatase, and we found that Ral expression is transcriptionally restricted to secondary cells. Thus during vulval development Ras switches effectors from Raf to RalGEF to promote divergent and mutually antagonistic cell fates, perhaps mirroring divergent effector usage in Ras-dependent tumors with differential pharmacological responsiveness.
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Affiliation(s)
- David J Reiner
- Department of Pharmacology and Lineberger Comprehensive Cancer Center; University of North Carolina; Chapel Hill, NC USA
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27
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Skorobogata O, Escobar-Restrepo JM, Rocheleau CE. An AGEF-1/Arf GTPase/AP-1 ensemble antagonizes LET-23 EGFR basolateral localization and signaling during C. elegans vulva induction. PLoS Genet 2014; 10:e1004728. [PMID: 25329472 PMCID: PMC4199573 DOI: 10.1371/journal.pgen.1004728] [Citation(s) in RCA: 14] [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: 06/28/2014] [Accepted: 09/02/2014] [Indexed: 02/07/2023] Open
Abstract
LET-23 Epidermal Growth Factor Receptor (EGFR) signaling specifies the vulval cell fates during C. elegans larval development. LET-23 EGFR localization on the basolateral membrane of the vulval precursor cells (VPCs) is required to engage the LIN-3 EGF-like inductive signal. The LIN-2 Cask/LIN-7 Veli/LIN-10 Mint (LIN-2/7/10) complex binds LET-23 EGFR, is required for its basolateral membrane localization, and therefore, vulva induction. Besides the LIN-2/7/10 complex, the trafficking pathways that regulate LET-23 EGFR localization have not been defined. Here we identify vh4, a hypomorphic allele of agef-1, as a strong suppressor of the lin-2 mutant Vulvaless (Vul) phenotype. AGEF-1 is homologous to the mammalian BIG1 and BIG2 Arf GTPase guanine nucleotide exchange factors (GEFs), which regulate secretory traffic between the Trans-Golgi network, endosomes and the plasma membrane via activation of Arf GTPases and recruitment of the AP-1 clathrin adaptor complex. Consistent with a role in trafficking we show that AGEF-1 is required for protein secretion and that AGEF-1 and the AP-1 complex regulate endosome size in coelomocytes. The AP-1 complex has previously been implicated in negative regulation of LET-23 EGFR, however the mechanism was not known. Our genetic data indicate that AGEF-1 is a strong negative regulator of LET-23 EGFR signaling that functions in the VPCs at the level of the receptor. In line with AGEF-1 being an Arf GEF, we identify the ARF-1.2 and ARF-3 GTPases as also negatively regulating signaling. We find that the agef-1(vh4) mutation results in increased LET-23 EGFR on the basolateral membrane in both wild-type and lin-2 mutant animals. Furthermore, unc-101(RNAi), a component of the AP-1 complex, increased LET-23 EGFR on the basolateral membrane in lin-2 and agef-1(vh4); lin-2 mutant animals. Thus, an AGEF-1/Arf GTPase/AP-1 ensemble functions opposite the LIN-2/7/10 complex to antagonize LET-23 EGFR basolateral membrane localization and signaling.
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Affiliation(s)
- Olga Skorobogata
- Division of Endocrinology and Metabolism, Department of Medicine, Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec, Canada
- Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec, Canada
| | | | - Christian E. Rocheleau
- Division of Endocrinology and Metabolism, Department of Medicine, Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec, Canada
- Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec, Canada
- * E-mail:
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28
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Jeon M, Zinn K. R3 receptor tyrosine phosphatases: conserved regulators of receptor tyrosine kinase signaling and tubular organ development. Semin Cell Dev Biol 2014; 37:119-26. [PMID: 25242281 DOI: 10.1016/j.semcdb.2014.09.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Accepted: 09/04/2014] [Indexed: 12/25/2022]
Abstract
R3 receptor tyrosine phosphatases (RPTPs) are characterized by extracellular domains composed solely of long chains of fibronectin type III repeats, and by the presence of a single phosphatase domain. There are five proteins in mammals with this structure, two in Drosophila and one in Caenorhabditis elegans. R3 RPTPs are selective regulators of receptor tyrosine kinase (RTK) signaling, and a number of different RTKs have been shown to be direct targets for their phosphatase activities. Genetic studies in both invertebrate model systems and in mammals have shown that R3 RPTPs are essential for tubular organ development. They also have important functions during nervous system development. R3 RPTPs are likely to be tumor suppressors in a number of types of cancer.
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Affiliation(s)
- Mili Jeon
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, United States; Department of Molecular and Cellular Physiology and Structural Biology, Howard Hughes Medical Institute, Stanford School of Medicine, Palo Alto, CA 94305, United States
| | - Kai Zinn
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, United States.
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29
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Hall BA, Jackson E, Hajnal A, Fisher J. Logic programming to predict cell fate patterns and retrodict genotypes in organogenesis. J R Soc Interface 2014; 11:20140245. [PMID: 24966232 DOI: 10.1098/rsif.2014.0245] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Caenorhabditis elegans vulval development is a paradigm system for understanding cell differentiation in the process of organogenesis. Through temporal and spatial controls, the fate pattern of six cells is determined by the competition of the LET-23 and the Notch signalling pathways. Modelling cell fate determination in vulval development using state-based models, coupled with formal analysis techniques, has been established as a powerful approach in predicting the outcome of combinations of mutations. However, computing the outcomes of complex and highly concurrent models can become prohibitive. Here, we show how logic programs derived from state machines describing the differentiation of C. elegans vulval precursor cells can increase the speed of prediction by four orders of magnitude relative to previous approaches. Moreover, this increase in speed allows us to infer, or 'retrodict', compatible genomes from cell fate patterns. We exploit this technique to predict highly variable cell fate patterns resulting from dig-1 reduced-function mutations and let-23 mosaics. In addition to the new insights offered, we propose our technique as a platform for aiding the design and analysis of experimental data.
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Affiliation(s)
| | - Ethan Jackson
- Microsoft Research, One Microsoft Way, Redmond, WA 98052, USA
| | - Alex Hajnal
- Institute of Molecular Life Sciences, University of Zurich, Zurich 8057, Switzerland
| | - Jasmin Fisher
- Microsoft Research, 21 Station Road, Cambridge CB1 2FB, UK Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
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30
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Schindler AJ, Sherwood DR. Morphogenesis of the caenorhabditis elegans vulva. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2014; 2:75-95. [PMID: 23418408 DOI: 10.1002/wdev.87] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Understanding how cells move, change shape, and alter cellular behaviors to form organs, a process termed morphogenesis, is one of the great challenges of developmental biology. Formation of the Caenorhabditis elegans vulva is a powerful, simple, and experimentally accessible model for elucidating how morphogenetic processes produce an organ. In the first step of vulval development, three epithelial precursor cells divide and differentiate to generate 22 cells of 7 different vulval subtypes. The 22 vulval cells then rearrange from a linear array into a tube, with each of the seven cell types undergoing characteristic morphogenetic behaviors that construct the vulva. Vulval morphogenesis entails many of the same cellular activities that underlie organogenesis and tissue formation across species, including invagination, lumen formation, oriented cell divisions, cell–cell adhesion, cell migration, cell fusion, extracellular matrix remodeling, and cell invasion. Studies of vulval development have led to pioneering discoveries in a number of these processes and are beginning to bridge the gap between the pathways that specify cells and their connections to morphogenetic behaviors. The simplicity of the vulva and the experimental tools available in C. elegans will continue to make vulval morphogenesis a powerful paradigm to further our understanding of the largely mysterious mechanisms that build tissues and organs.
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31
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HER. Mol Oncol 2013. [DOI: 10.1017/cbo9781139046947.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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32
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Ortuso F, Paduano F, Carotenuto A, Gomez-Monterrey I, Bilotta A, Gaudio E, Sala M, Artese A, Vernieri E, Dattilo V, Iuliano R, Brancaccio D, Bertamino A, Musella S, Alcaro S, Grieco P, Perrotti N, Croce CM, Novellino E, Fusco A, Campiglia P, Trapasso F. Discovery of PTPRJ agonist peptides that effectively inhibit in vitro cancer cell proliferation and tube formation. ACS Chem Biol 2013; 8:1497-506. [PMID: 23627474 DOI: 10.1021/cb3007192] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
PTPRJ is a receptor protein tyrosine phosphatase involved in both physiological and oncogenic pathways. We previously reported that its expression is strongly reduced in the majority of explored cancer cell lines and tumor samples; moreover, its restoration blocks in vitro cancer cell proliferation and in vivo tumor formation. By means of a phage display library screening, we recently identified two peptides able to bind and activate PTPRJ, resulting in cell growth inhibition and apoptosis of both cancer and endothelial cells. Here, on a previously discovered PTPRJ agonist peptide, PTPRJ-pep19, we synthesized and assayed a panel of nonapeptide analogues with the aim to identify specific amino acid residues responsible for peptide activity. These second-generation nonapeptides were tested on both cancer and primary endothelial cells (HeLa and HUVEC, respectively); interestingly, one of them (PTPRJ-19.4) was able to both dramatically reduce cell proliferation and effectively trigger apoptosis of both HeLa and HUVECs compared to its first-generation counterpart. Moreover, PTPRJ-pep19.4 significantly inhibited in vitro tube formation on Matrigel. Intriguingly, while ERK1/2 phosphorylation and cell proliferation were both inhibited by PTPRJ-pep19.4 in breast cancer cells (MCF-7 and SKBr3), no effects were observed on primary normal human mammary endothelial cells (HMEC). We further characterized these peptides by molecular modeling and NMR experiments reporting, for the most active peptide, the possibility of self-aggregation states and highlighting new hints of structure-activity relationship. Thus, our results indicate that this nonapeptide might represent a great potential lead for the development of novel targeted anticancer drugs.
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Affiliation(s)
| | | | - Alfonso Carotenuto
- Dipartimento
di Farmacia, Università degli Studi di Napoli “Federico II”, 80131 Napoli, Italy
| | - Isabel Gomez-Monterrey
- Dipartimento
di Farmacia, Università degli Studi di Napoli “Federico II”, 80131 Napoli, Italy
| | | | - Eugenio Gaudio
- Department of Molecular Virology,
Immunology and Medical Genetics and Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio 43210, United
States
| | - Marina Sala
- Dipartimento
di Farmacia, Università degli Studi di Napoli “Federico II”, 80131 Napoli, Italy
| | | | | | | | | | - Diego Brancaccio
- Dipartimento
di Farmacia, Università degli Studi di Napoli “Federico II”, 80131 Napoli, Italy
| | - Alessia Bertamino
- Dipartimento di
Farmacia, Università di Salerno,
84084 Fisciano, Italy
| | - Simona Musella
- Dipartimento di
Farmacia, Università di Salerno,
84084 Fisciano, Italy
| | | | - Paolo Grieco
- Dipartimento
di Farmacia, Università degli Studi di Napoli “Federico II”, 80131 Napoli, Italy
| | | | - Carlo M. Croce
- Department of Molecular Virology,
Immunology and Medical Genetics and Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio 43210, United
States
| | - Ettore Novellino
- Dipartimento
di Farmacia, Università degli Studi di Napoli “Federico II”, 80131 Napoli, Italy
| | - Alfredo Fusco
- Dipartimento
di Biologia e Patologia Cellulare e Molecolare c/o Istituto di Endocrinologia
ed Oncologia Sperimentale del CNR, Università degli Studi di Napoli “Federico II”, 80131
Napoli, Italy
| | - Pietro Campiglia
- Dipartimento di
Farmacia, Università di Salerno,
84084 Fisciano, Italy
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33
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Abstract
Receptor Tyrosine Kinase (RTK)-Ras-Extracellular signal-regulated kinase (ERK) signaling pathways control many aspects of C. elegans development and behavior. Studies in C. elegans helped elucidate the basic framework of the RTK-Ras-ERK pathway and continue to provide insights into its complex regulation, its biological roles, how it elicits cell-type appropriate responses, and how it interacts with other signaling pathways to do so. C. elegans studies have also revealed biological contexts in which alternative RTK- or Ras-dependent pathways are used instead of the canonical pathway.
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Affiliation(s)
- Meera V Sundaram
- Dept. of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104-6145, USA.
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34
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de la Cova C, Greenwald I. SEL-10/Fbw7-dependent negative feedback regulation of LIN-45/Braf signaling in C. elegans via a conserved phosphodegron. Genes Dev 2013; 26:2524-35. [PMID: 23154983 DOI: 10.1101/gad.203703.112] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The conserved E3 ubiquitin ligase component named SEL-10 in Caenorhabditis elegans and Fbw7 in mammals targets substrates for ubiquitin-mediated degradation through a high-affinity binding site called a Cdc4 phosphodegron (CPD). As many known substrates of Fbw7 are oncoproteins, the identification of new substrates may offer insight into cancer biology as well as aspects of proteome regulation. Here, we evaluated whether the presence of an evolutionarily conserved CPD would be a feasible complement to proteomics-based approaches for identifying new potential substrates. For functional assessments, we focused on LIN-45, a component of the signal transduction pathway underlying vulval induction and the ortholog of human Braf, an effector of Ras in numerous cancers. Our analysis demonstrates that LIN-45 behaves as a bona fide substrate of SEL-10, with mutation of the CPD or loss of sel-10 resulting in increased activity and protein stability in vivo. Furthermore, during vulval induction, the downstream kinase MPK-1/ERK is also required for LIN-45 protein degradation in a negative feedback loop, resulting in degradation of LIN-45 where ERK is highly active. As the CPD consensus sequence is conserved in human Braf, we propose that Fbw7 may also regulate Braf stability in some cell contexts. We discuss the implications of our findings for vulval development in C. elegans, the potential applicability to human Braf, and the value of a CPD-based predictive approach for human Fbw7 substrates.
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35
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Paduano F, Ortuso F, Campiglia P, Raso C, Iaccino E, Gaspari M, Gaudio E, Mangone G, Carotenuto A, Bilotta A, Narciso D, Palmieri C, Agosti V, Artese A, Gomez-Monterrey I, Sala M, Cuda G, Iuliano R, Perrotti N, Scala G, Viglietto G, Alcaro S, Croce CM, Novellino E, Fusco A, Trapasso F. Isolation and functional characterization of peptide agonists of PTPRJ, a tyrosine phosphatase receptor endowed with tumor suppressor activity. ACS Chem Biol 2012; 7:1666-76. [PMID: 22759068 DOI: 10.1021/cb300281t] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
PTPRJ is a receptor-type protein tyrosine phosphatase whose expression is strongly reduced in the majority of investigated cancer cell lines and tumor specimens. PTPRJ negatively interferes with mitogenic signals originating from several oncogenic receptor tyrosine kinases, including HGFR, PDGFR, RET, and VEGFR-2. Here we report the isolation and characterization of peptides from a random peptide phage display library that bind and activate PTPRJ. These agonist peptides, which are able to both circularize and form dimers in acqueous solution, were assayed for their biochemical and biological activity on both human cancer cells and primary endothelial cells (HeLa and HUVEC, respectively). Our results demonstrate that binding of PTPRJ-interacting peptides to cell cultures dramatically reduces the extent of both MAPK phosphorylation and total phosphotyrosine levels; conversely, they induce a significant increase of the cell cycle inhibitor p27(Kip1). Moreover, PTPRJ agonist peptides both reduce proliferation and trigger apoptosis of treated cells. Our data indicate that peptide agonists of PTPRJ positively modulate the PTPRJ activity and may lead to novel targeted anticancer therapies.
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Affiliation(s)
- Francesco Paduano
- Dipartimento di Medicina Sperimentale
e Clinica, Università “Magna Græcia” di Catanzaro, Campus “S. Venuta”, 88100
Catanzaro, Italy
| | - Francesco Ortuso
- Laboratorio
di Chimica Farmaceutica
Computazionale, Dipartimento di Scienze Farmacobiologiche, Università “Magna Græcia” di Catanzaro, Campus “S. Venuta”, 88100 Catanzaro, Italy
| | - Pietro Campiglia
- Dipartimento di Scienze Farmaceutiche
e Biomediche, Sezione Chimico-Tecnologica, Università di Salerno, 84084 Fisciano (Salerno), Italy
| | - Cinzia Raso
- Dipartimento di Medicina Sperimentale
e Clinica, Università “Magna Græcia” di Catanzaro, Campus “S. Venuta”, 88100
Catanzaro, Italy
| | - Enrico Iaccino
- Dipartimento di Medicina Sperimentale
e Clinica, Università “Magna Græcia” di Catanzaro, Campus “S. Venuta”, 88100
Catanzaro, Italy
| | - Marco Gaspari
- Dipartimento di Medicina Sperimentale
e Clinica, Università “Magna Græcia” di Catanzaro, Campus “S. Venuta”, 88100
Catanzaro, Italy
| | - Eugenio Gaudio
- Dipartimento di Medicina Sperimentale
e Clinica, Università “Magna Græcia” di Catanzaro, Campus “S. Venuta”, 88100
Catanzaro, Italy
- Department of Molecular Virology,
Immunology and Medical Genetics and Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio 43210, United
States
| | - Graziella Mangone
- Dipartimento di Medicina Sperimentale
e Clinica, Università “Magna Græcia” di Catanzaro, Campus “S. Venuta”, 88100
Catanzaro, Italy
| | - Alfonso Carotenuto
- Dipartimento di
Chimica Farmaceutica
e Tossicologica, Università degli Studi di Napoli “Federico II”, 80131 Naples, Italy
| | - Anna Bilotta
- Dipartimento di Medicina Sperimentale
e Clinica, Università “Magna Græcia” di Catanzaro, Campus “S. Venuta”, 88100
Catanzaro, Italy
| | - Domenico Narciso
- Dipartimento di Medicina Sperimentale
e Clinica, Università “Magna Græcia” di Catanzaro, Campus “S. Venuta”, 88100
Catanzaro, Italy
| | - Camillo Palmieri
- Dipartimento di Medicina Sperimentale
e Clinica, Università “Magna Græcia” di Catanzaro, Campus “S. Venuta”, 88100
Catanzaro, Italy
| | - Valter Agosti
- Dipartimento di Medicina Sperimentale
e Clinica, Università “Magna Græcia” di Catanzaro, Campus “S. Venuta”, 88100
Catanzaro, Italy
| | - Anna Artese
- Laboratorio
di Chimica Farmaceutica
Computazionale, Dipartimento di Scienze Farmacobiologiche, Università “Magna Græcia” di Catanzaro, Campus “S. Venuta”, 88100 Catanzaro, Italy
| | - Isabel Gomez-Monterrey
- Dipartimento di
Chimica Farmaceutica
e Tossicologica, Università degli Studi di Napoli “Federico II”, 80131 Naples, Italy
| | - Marina Sala
- Dipartimento di Scienze Farmaceutiche
e Biomediche, Sezione Chimico-Tecnologica, Università di Salerno, 84084 Fisciano (Salerno), Italy
| | - Giovanni Cuda
- Dipartimento di Medicina Sperimentale
e Clinica, Università “Magna Græcia” di Catanzaro, Campus “S. Venuta”, 88100
Catanzaro, Italy
| | - Rodolfo Iuliano
- Dipartimento di Medicina Sperimentale
e Clinica, Università “Magna Græcia” di Catanzaro, Campus “S. Venuta”, 88100
Catanzaro, Italy
| | - Nicola Perrotti
- Dipartimento di Medicina Sperimentale
e Clinica, Università “Magna Græcia” di Catanzaro, Campus “S. Venuta”, 88100
Catanzaro, Italy
| | - Giuseppe Scala
- Dipartimento di Medicina Sperimentale
e Clinica, Università “Magna Græcia” di Catanzaro, Campus “S. Venuta”, 88100
Catanzaro, Italy
| | - Giuseppe Viglietto
- Dipartimento di Medicina Sperimentale
e Clinica, Università “Magna Græcia” di Catanzaro, Campus “S. Venuta”, 88100
Catanzaro, Italy
| | - Stefano Alcaro
- Laboratorio
di Chimica Farmaceutica
Computazionale, Dipartimento di Scienze Farmacobiologiche, Università “Magna Græcia” di Catanzaro, Campus “S. Venuta”, 88100 Catanzaro, Italy
| | - Carlo M. Croce
- Department of Molecular Virology,
Immunology and Medical Genetics and Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio 43210, United
States
| | - Ettore Novellino
- Dipartimento di
Chimica Farmaceutica
e Tossicologica, Università degli Studi di Napoli “Federico II”, 80131 Naples, Italy
| | - Alfredo Fusco
- Dipartimento di Biologia e Patologia
Cellulare e Molecolare c/o Istituto di Endocrinologia ed Oncologia
Sperimentale del CNR, Università degli Studi di Napoli “Federico II”, 80131 Naples, Italy
| | - Francesco Trapasso
- Dipartimento di Medicina Sperimentale
e Clinica, Università “Magna Græcia” di Catanzaro, Campus “S. Venuta”, 88100
Catanzaro, Italy
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36
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37
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Skorobogata O, Rocheleau CE. RAB-7 antagonizes LET-23 EGFR signaling during vulva development in Caenorhabditis elegans. PLoS One 2012; 7:e36489. [PMID: 22558469 PMCID: PMC3340361 DOI: 10.1371/journal.pone.0036489] [Citation(s) in RCA: 21] [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: 10/19/2011] [Accepted: 04/07/2012] [Indexed: 12/20/2022] Open
Abstract
The Rab7 GTPase regulates late endosome trafficking of the Epidermal Growth Factor Receptor (EGFR) to the lysosome for degradation. However, less is known about how Rab7 activity, functioning late in the endocytic pathway, affects EGFR signaling. Here we used Caenorhabditis elegans vulva cell fate induction, a paradigm for genetic analysis of EGFR/Receptor Tyrosine Kinase (RTK) signaling, to assess the genetic requirements for rab-7. Using a rab-7 deletion mutant, we demonstrate that rab-7 antagonizes LET-23 EGFR signaling to a similar extent, but in a distinct manner, as previously described negative regulators such as sli-1 c-Cbl. Epistasis analysis places rab-7 upstream of or in parallel to lin-3 EGF and let-23 EGFR. However, expression of gfp::rab-7 in the Vulva Presursor Cells (VPCs) is sufficient to rescue the rab-7(-) VPC induction phenotypes indicating that RAB-7 functions in the signal receiving cell. We show that components of the Endosomal Sorting Complex Required for Transport (ESCRT)-0, and -I, complexes, hgrs-1 Hrs, and vps-28, also antagonize signaling, suggesting that LET-23 EGFR likely transits through Multivesicular Bodies (MVBs) en route to the lysosome. Consistent with RAB-7 regulating LET-23 EGFR trafficking, rab-7 mutants have increased number of LET-23::GFP-positive endosomes. Our data imply that Rab7, by mediating EGFR trafficking and degradation, plays an important role in downregulation of EGFR signaling. Failure to downregulate EGFR signaling contributes to oncogenesis, and thus Rab7 could possess tumor suppressor activity in humans.
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Affiliation(s)
- Olga Skorobogata
- Division of Endocrinology and Metabolism, Department of Medicine, McGill University and McGill University Health Centre Research Institute, Montreal, Quebec, Canada
| | - Christian E. Rocheleau
- Division of Endocrinology and Metabolism, Department of Medicine, McGill University and McGill University Health Centre Research Institute, Montreal, Quebec, Canada
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38
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Jeon M, Scott MP, Zinn K. Interactions between Type III receptor tyrosine phosphatases and growth factor receptor tyrosine kinases regulate tracheal tube formation in Drosophila. Biol Open 2012; 1:548-58. [PMID: 23213447 PMCID: PMC3509443 DOI: 10.1242/bio.2012471] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The respiratory (tracheal) system of the Drosophila melanogaster larva is an intricate branched network of air-filled tubes. Its developmental logic is similar in some ways to that of the vertebrate vascular system. We previously described a unique embryonic tracheal tubulogenesis phenotype caused by loss of both of the Type III receptor tyrosine phosphatases (RPTPs), Ptp4E and Ptp10D. In Ptp4E Ptp10D double mutants, the linear tubes in unicellular and terminal tracheal branches are converted into bubble-like cysts that incorporate apical cell surface markers. This tube geometry phenotype is modulated by changes in the activity or expression of the epidermal growth factor receptor (Egfr) tyrosine kinase (TK). Ptp10D physically interacts with Egfr. Here we demonstrate that the Ptp4E Ptp10D phenotype is the consequence of the loss of negative regulation by the RPTPs of three growth factor receptor TKs: Egfr, Breathless and Pvr. Reducing the activity of any of the three kinases by tracheal expression of dominant-negative mutants suppresses cyst formation. By competing dominant-negative and constitutively active kinase mutants against each other, we show that the three RTKs have partially interchangeable activities, so that increasing the activity of one kinase can compensate for the effects of reducing the activity of another. This implies that SH2-domain downstream effectors that are required for the phenotype are likely to be able to interact with phosphotyrosine sites on all three receptor TKs. We also show that the phenotype involves increases in signaling through the MAP kinase and Rho GTPase pathways.
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Affiliation(s)
- Mili Jeon
- Division of Biology 114-96, California Institute of Technology , 1200 East California Boulevard, Pasadena, CA 91125 , USA ; Departments of Developmental Biology, Genetics, and Bioengineering, Howard Hughes Medical Institute, 318 Campus Drive, Stanford University School of Medicine , Palo Alto, CA 94305 , USA
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Fertig EJ, Danilova LV, Favorov AV, Ochs MF. Hybrid Modeling of Cell Signaling and Transcriptional Reprogramming and Its Application in C. elegans Development. Front Genet 2011; 2:77. [PMID: 22303372 PMCID: PMC3268630 DOI: 10.3389/fgene.2011.00077] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2011] [Accepted: 10/17/2011] [Indexed: 12/16/2022] Open
Abstract
Modeling of signal driven transcriptional reprogramming is critical for understanding of organism development, human disease, and cell biology. Many current modeling techniques discount key features of the biological sub-systems when modeling multiscale, organism-level processes. We present a mechanistic hybrid model, GESSA, which integrates a novel pooled probabilistic Boolean network model of cell signaling and a stochastic simulation of transcription and translation responding to a diffusion model of extracellular signals. We apply the model to simulate the well studied cell fate decision process of the vulval precursor cells (VPCs) in C. elegans, using experimentally derived rate constants wherever possible and shared parameters to avoid overfitting. We demonstrate that GESSA recovers (1) the effects of varying scaffold protein concentration on signal strength, (2) amplification of signals in expression, (3) the relative external ligand concentration in a known geometry, and (4) feedback in biochemical networks. We demonstrate that setting model parameters based on wild-type and LIN-12 loss-of-function mutants in C. elegans leads to correct prediction of a wide variety of mutants including partial penetrance of phenotypes. Moreover, the model is relatively insensitive to parameters, retaining the wild-type phenotype for a wide range of cell signaling rate parameters.
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Affiliation(s)
- Elana J. Fertig
- Division of Oncology Biostatistics and Bioinformatics, Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins UniversityBaltimore, MD, USA
| | - Ludmila V. Danilova
- Division of Oncology Biostatistics and Bioinformatics, Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins UniversityBaltimore, MD, USA
| | - Alexander V. Favorov
- Division of Oncology Biostatistics and Bioinformatics, Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins UniversityBaltimore, MD, USA
- Scientific Center of RF GosNIIGenetikaMoscow, Russia
- Vavilov Institute of General Genetics of RASMoscow, Russia
| | - Michael F. Ochs
- Division of Oncology Biostatistics and Bioinformatics, Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins UniversityBaltimore, MD, USA
- Department of Health Science Informatics, School of Medicine, Johns Hopkins UniversityBaltimore, MD, USA
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Di Rubbo S, Irani NG, Russinova E. PP2A phosphatases: the "on-off" regulatory switches of brassinosteroid signaling. Sci Signal 2011; 4:pe25. [PMID: 21558552 DOI: 10.1126/scisignal.2002046] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Inactivation of ligand-bound plasma membrane receptors is crucial for the regulation of their signaling outputs. The internalization of activated receptors and their subsequent targeting for recycling or degradation is controlled by posttranslational modifications, of which phosphorylation and dephosphorylation play an important role. Recent work suggests that a similar mechanism acts on the brassinosteroid (BR) receptor BR INSENSITIVE 1 (BRI1) in Arabidopsis thaliana to switch off BR signaling. The degradation of BRI1 requires a protein phosphatase 2A (PP2A)-mediated dephosphorylation that is specified by methylation of the phosphatase by a leucine carboxylmethyltransferase on membranes. PP2A is also reported to act positively on BR signaling by targeting the transcription factor BRASSINAZOLE-RESISTANT 1 (BZR1), a component downstream of BRI1. Thus, PP2A proteins play a dual role in the regulation of the BR pathway to switch between inhibition and activation of the BR signaling, depending on their substrate specificity and localization.
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Affiliation(s)
- Simone Di Rubbo
- Department of Plant Systems Biology, VIB, Technologiepark 927, 9052 Gent, Belgium
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Arora D, Stopp S, Böhmer SA, Schons J, Godfrey R, Masson K, Razumovskaya E, Rönnstrand L, Tänzer S, Bauer R, Böhmer FD, Müller JP. Protein-tyrosine phosphatase DEP-1 controls receptor tyrosine kinase FLT3 signaling. J Biol Chem 2011; 286:10918-29. [PMID: 21262971 PMCID: PMC3064147 DOI: 10.1074/jbc.m110.205021] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2010] [Revised: 01/21/2011] [Indexed: 12/15/2022] Open
Abstract
Fms-like tyrosine kinase 3 (FLT3) plays an important role in hematopoietic differentiation, and constitutively active FLT3 mutant proteins contribute to the development of acute myeloid leukemia. Little is known about the protein-tyrosine phosphatases (PTP) affecting the signaling activity of FLT3. To identify such PTP, myeloid cells expressing wild type FLT3 were infected with a panel of lentiviral pseudotypes carrying shRNA expression cassettes targeting different PTP. Out of 20 PTP tested, expressed in hematopoietic cells, or presumed to be involved in oncogenesis or tumor suppression, DEP-1 (PTPRJ) was identified as a PTP negatively regulating FLT3 phosphorylation and signaling. Stable 32D myeloid cell lines with strongly reduced DEP-1 levels showed site-selective hyperphosphorylation of FLT3. In particular, the sites pTyr-589, pTyr-591, and pTyr-842 involved in the FLT3 ligand (FL)-mediated activation of FLT3 were hyperphosphorylated the most. Similarly, acute depletion of DEP-1 in the human AML cell line THP-1 caused elevated FLT3 phosphorylation. Direct interaction of DEP-1 and FLT3 was demonstrated by "substrate trapping" experiments showing association of DEP-1 D1205A or C1239S mutant proteins with FLT3 by co-immunoprecipitation. Moreover, activated FLT3 could be dephosphorylated by recombinant DEP-1 in vitro. Enhanced FLT3 phosphorylation in DEP-1-depleted cells was accompanied by enhanced FLT3-dependent activation of ERK and cell proliferation. Stable overexpression of DEP-1 in 32D cells and transient overexpression with FLT3 in HEK293 cells resulted in reduction of FL-mediated FLT3 signaling activity. Furthermore, FL-stimulated colony formation of 32D cells expressing FLT3 in methylcellulose was induced in response to shRNA-mediated DEP-1 knockdown. This transforming effect of DEP-1 knockdown was consistent with a moderately increased activation of STAT5 upon FL stimulation but did not translate into myeloproliferative disease formation in the 32D-C3H/HeJ mouse model. The data indicate that DEP-1 is negatively regulating FLT3 signaling activity and that its loss may contribute to but is not sufficient for leukemogenic cell transformation.
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Affiliation(s)
- Deepika Arora
- From the Institute of Molecular Cell Biology, Center for Molecular Biomedicine, Friedrich Schiller University, D-07745 Jena, Germany
| | - Sabine Stopp
- From the Institute of Molecular Cell Biology, Center for Molecular Biomedicine, Friedrich Schiller University, D-07745 Jena, Germany
| | - Sylvia-Annette Böhmer
- From the Institute of Molecular Cell Biology, Center for Molecular Biomedicine, Friedrich Schiller University, D-07745 Jena, Germany
| | - Julia Schons
- From the Institute of Molecular Cell Biology, Center for Molecular Biomedicine, Friedrich Schiller University, D-07745 Jena, Germany
| | - Rinesh Godfrey
- From the Institute of Molecular Cell Biology, Center for Molecular Biomedicine, Friedrich Schiller University, D-07745 Jena, Germany
| | - Kristina Masson
- the Experimental Clinical Chemistry, Department of Laboratory Medicine, Lund University, Malmö University Hospital, SE-20502 Malmö, Sweden, and
| | - Elena Razumovskaya
- the Experimental Clinical Chemistry, Department of Laboratory Medicine, Lund University, Malmö University Hospital, SE-20502 Malmö, Sweden, and
| | - Lars Rönnstrand
- the Experimental Clinical Chemistry, Department of Laboratory Medicine, Lund University, Malmö University Hospital, SE-20502 Malmö, Sweden, and
| | - Simone Tänzer
- the Research Group Immunology, Leibniz-Institute for Age Research-Fritz-Lipmann-Institute, D-07745 Jena, Germany
| | - Reinhard Bauer
- From the Institute of Molecular Cell Biology, Center for Molecular Biomedicine, Friedrich Schiller University, D-07745 Jena, Germany
| | - Frank-D. Böhmer
- From the Institute of Molecular Cell Biology, Center for Molecular Biomedicine, Friedrich Schiller University, D-07745 Jena, Germany
| | - Jörg P. Müller
- From the Institute of Molecular Cell Biology, Center for Molecular Biomedicine, Friedrich Schiller University, D-07745 Jena, Germany
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Avraham R, Yarden Y. Feedback regulation of EGFR signalling: decision making by early and delayed loops. Nat Rev Mol Cell Biol 2011; 12:104-17. [PMID: 21252999 DOI: 10.1038/nrm3048] [Citation(s) in RCA: 494] [Impact Index Per Article: 38.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Human-made information relay systems invariably incorporate central regulatory components, which are mirrored in biological systems by dense feedback and feedforward loops. This type of system control is exemplified by positive and negative feedback loops (for example, receptor endocytosis and dephosphorylation) that enable growth factors and receptor Tyr kinases of the epidermal growth factor receptor (EGFR)/ERBB family to regulate cellular function. Recent studies show that the collection of feedback regulatory loops can perform computational tasks - such as decoding ligand specificity, transforming graded input signals into a digital output and regulating response kinetics. Aberrant signal processing and feedback regulation can lead to defects associated with pathologies such as cancer.
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Affiliation(s)
- Roi Avraham
- Department of Biological Regulation, The Weizmann Institute of Science, Rehovot 76100, Israel
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Zand TP, Reiner DJ, Der CJ. Ras effector switching promotes divergent cell fates in C. elegans vulval patterning. Dev Cell 2011; 20:84-96. [PMID: 21238927 PMCID: PMC3028984 DOI: 10.1016/j.devcel.2010.12.004] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2010] [Revised: 10/21/2010] [Accepted: 11/24/2010] [Indexed: 11/19/2022]
Abstract
The C. elegans vulva is patterned by epidermal growth factor (EGF) activation of Ras to control 1° fate, and 1° fate induces antagonistic Notch-dependent 2° fate. Furthermore, a spatial EGF gradient, in addition to inducing 1° fate, directly contributes to 2° fate via an unknown pathway. We find that in addition to its canonical effector, Raf, vulval Ras utilizes an exchange factor for the Ral small GTPase (RalGEF), such that Ras-RalGEF-Ral antagonizes Ras-Raf pro-1° fate activity. Consistent with its restricted expression pattern, Ral participates in EGF pro-2° activity. Thus, we have delineated a Ras effector-switching mechanism whereby position within the morphogen gradient dictates that Ras effector usage is switched to RalGEF from Raf to promote 2° instead of 1° fate. Our observations define the utility of Ras effector switching during normal development and may provide a possible mechanistic basis for cell and cancer-type differences in effector dependency and activation.
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Affiliation(s)
- Tanya P. Zand
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599, U.S.A
- Department of Pharmacology, University of North Carolina, Chapel Hill, NC 27599, U.S.A
| | - David J. Reiner
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599, U.S.A
- Department of Pharmacology, University of North Carolina, Chapel Hill, NC 27599, U.S.A
| | - Channing J. Der
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599, U.S.A
- Department of Pharmacology, University of North Carolina, Chapel Hill, NC 27599, U.S.A
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Robert VJP, Bessereau JL. Genome engineering by transgene-instructed gene conversion in C. elegans. Methods Cell Biol 2011; 106:65-88. [PMID: 22118274 DOI: 10.1016/b978-0-12-544172-8.00003-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The nematode Caenorhabditis elegans is an anatomically simple metazoan that has been used over the last 40 years to address an extremely wide range of biological questions. One major advantage of the C. elegans system is the possibility to conduct large-scale genetic screens on randomly mutagenized animals, either looking for a phenotype of interest and subsequently relate the mutated gene to the biological process under study ("forward genetics"), or screening for molecular lesions impairing the function of a specific gene and later analyze the phenotype of the mutant ("reverse genetics"). However, the nature of the genomic lesion is not controlled in either strategy. Here we describe a technique to engineer customized mutations in the C. elegans genome by homologous recombination. This technique, called MosTIC (for Mos1 excision induced transgene-instructed gene conversion), requires a C. elegans strain containing an insertion of the Drosophila transposon Mos1 within the locus to modify. Expression of the Mos transposase in the germ line triggers Mos1 excision, which causes a DNA double strand break (DSB) in the chromosome at the excision site. The DSB locally stimulates DNA repair by homologous recombination, which can sometimes occur between the chromosome and a transgene containing sequence homologous to the broken locus. In that case, sequence variations contained in the repair template will be copied by gene conversion into the genome. Here we provide a detailed protocol of the MosTIC technique, which can be used to introduce point mutations and generate knockout and knock-in alleles.
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Affiliation(s)
- Valérie J P Robert
- Ecole Normale Supérieure, Institut de Biologie de l'ENS, IBENS, Paris, France
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Janicke M, Renisch B, Hammerschmidt M. Zebrafish grainyhead-like1 is a common marker of different non-keratinocyte epidermal cell lineages, which segregate from each other in a Foxi3-dependent manner. THE INTERNATIONAL JOURNAL OF DEVELOPMENTAL BIOLOGY 2010; 54:837-50. [PMID: 19757382 DOI: 10.1387/ijdb.092877mj] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Grainyhead/CP2 transcription factor family members are widely conserved among the animal kingdom and have been implicated in different developmental processes. Thus far, nothing has been known about their roles in zebrafish. Here we identify seven zebrafish grainyhead-like (grhl) / cp2 genes, with focus on grhl1, which is expressed in the periderm and in epidermal ionocyte progenitors, but downregulated when ionocytes differentiate. In addition, expression was detected in other "non-keratinocyte" cell types of the epidermis, such as pvalb8-expressing cells, which according to our lineage tracing experiments are derived from the same pool of progenitor cells like keratinocytes and ionocytes. Antisense morpholino oligonucleotide-based loss-of-function analysis revealed that grhl1 is dispensable for the development and function of all investigated epidermal cell types, but required as a negative regulator of its own transcription during ionocyte differentiation. Knockdown of the transcription factor Foxi3a, which is expressed in a subset of the grhl1 population, caused a loss of ionocytes and a corresponding increase in the number of pvalb8-expressing cells, while leaving the number of grhl1-positive cells unaltered. We propose that grhl1 is a novel common marker of all or most "non-keratinocyte" epidermal progenitors, and that the sub-functionalisation of these cells is regulated by differential positive and negative effects of Foxi3 factors.
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Avraham R, Sas-Chen A, Manor O, Steinfeld I, Shalgi R, Tarcic G, Bossel N, Zeisel A, Amit I, Zwang Y, Enerly E, Russnes HG, Biagioni F, Mottolese M, Strano S, Blandino G, Børresen-Dale AL, Pilpel Y, Yakhini Z, Segal E, Yarden Y. EGF decreases the abundance of microRNAs that restrain oncogenic transcription factors. Sci Signal 2010; 3:ra43. [PMID: 20516477 DOI: 10.1126/scisignal.2000876] [Citation(s) in RCA: 91] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Epidermal growth factor (EGF) stimulates cells by launching gene expression programs that are frequently deregulated in cancer. MicroRNAs, which attenuate gene expression by binding complementary regions in messenger RNAs, are broadly implicated in cancer. Using genome-wide approaches, we showed that EGF stimulation initiates a coordinated transcriptional program of microRNAs and transcription factors. The earliest event involved a decrease in the abundance of a subset of 23 microRNAs. This step permitted rapid induction of oncogenic transcription factors, such as c-FOS, encoded by immediate early genes. In line with roles as suppressors of EGF receptor (EGFR) signaling, we report that the abundance of this early subset of microRNAs is decreased in breast and in brain tumors driven by the EGFR or the closely related HER2. These findings identify specific microRNAs as attenuators of growth factor signaling and oncogenesis.
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Affiliation(s)
- Roi Avraham
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel
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Abstract
Although now dogma, the idea that nonvertebrate organisms such as yeast, worms, and flies could inform, and in some cases even revolutionize, our understanding of oncogenesis in humans was not immediately obvious. Aided by the conservative nature of evolution and the persistence of a cohort of devoted researchers, the role of model organisms as a key tool in solving the cancer problem has, however, become widely accepted. In this review, we focus on the nematode Caenorhabditis elegans and its diverse and sometimes surprising contributions to our understanding of the tumorigenic process. Specifically, we discuss findings in the worm that address a well-defined set of processes known to be deregulated in cancer cells including cell cycle progression, growth factor signaling, terminal differentiation, apoptosis, the maintenance of genome stability, and developmental mechanisms relevant to invasion and metastasis.
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Affiliation(s)
- Natalia V. Kirienko
- University of Wyoming, College of Agriculture, Department of Molecular Biology, Dept 3944, 1000 E. University Avenue, Laramie, WY 82071
| | - Kumaran Mani
- University of Wyoming, College of Agriculture, Department of Molecular Biology, Dept 3944, 1000 E. University Avenue, Laramie, WY 82071
| | - David S. Fay
- University of Wyoming, College of Agriculture, Department of Molecular Biology, Dept 3944, 1000 E. University Avenue, Laramie, WY 82071
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Tarcic G, Boguslavsky SK, Wakim J, Kiuchi T, Liu A, Reinitz F, Nathanson D, Takahashi T, Mischel PS, Ng T, Yarden Y. An unbiased screen identifies DEP-1 tumor suppressor as a phosphatase controlling EGFR endocytosis. Curr Biol 2010; 19:1788-98. [PMID: 19836242 DOI: 10.1016/j.cub.2009.09.048] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2009] [Revised: 09/15/2009] [Accepted: 09/15/2009] [Indexed: 01/26/2023]
Abstract
BACKGROUND The epidermal growth factor (EGF) stimulates rapid tyrosine phosphorylation of the EGF receptor (EGFR). This event precedes signaling from both the plasma membrane and from endosomes, and it is essential for recruitment of a ubiquitin ligase, CBL, that sorts activated receptors to endosomes and degradation. Because hyperphosphorylation of EGFR is involved in oncogenic pathways, we performed an unbiased screen of small interfering RNA (siRNA) oligonucleotides targeting all human tyrosine phosphatases. RESULTS We report the identification of PTPRK and PTPRJ (density-enhanced phosphatase-1 [DEP-1]) as EGFR-targeting phosphatases. DEP-1 is a tumor suppressor that dephosphorylates and thereby stabilizes EGFR by hampering its ability to associate with the CBL-GRB2 ubiquitin ligase complex. DEP-1 silencing enhanced tyrosine phosphorylation of endosomal EGFRs and, accordingly, increased cell proliferation. In line with functional interactions, EGFR and DEP-1 form physical associations, and EGFR phosphorylates a substrate-trapping mutant of DEP-1. Interestingly, the interactions of DEP-1 and EGFR are followed by physical segregation: whereas EGFR undergoes endocytosis, DEP-1 remains confined to the cell surface. CONCLUSIONS EGFR and DEP-1 physically interact at the cell surface and maintain bidirectional enzyme-substrate interactions, which are relevant to their respective oncogenic and tumor-suppressive functions. These observations highlight the emerging roles of vesicular trafficking in malignant processes.
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Affiliation(s)
- Gabi Tarcic
- Department of Biological Regulation, The Weizmann Institute of Science, Rehovot 76100, Israel
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Fisher K, Southall SM, Wilson JR, Poulin GB. Methylation and demethylation activities of a C. elegans MLL-like complex attenuate RAS signalling. Dev Biol 2010; 341:142-53. [PMID: 20188723 DOI: 10.1016/j.ydbio.2010.02.023] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2010] [Accepted: 02/12/2010] [Indexed: 12/16/2022]
Abstract
The conserved Mixed Lineage Leukaemia (MLL) complex deposits activating methyl marks on histone tails through a methyltransferase (MT) activity. Here we provide in vivo evidence that in addition to methylation, the C. elegans MLL-like complex can remove specific methyl marks linked to repression of transcription. This supports the proposed model in which the MLL complex orchestrates both the deposition and the removal of methyl marks to activate transcription. We have uncovered the MLL-like complex in a large-scale RNAi screen designed to identify attenuators of RAS signalling during vulval development. We have also found that the histone acetyltransferase complex, NuA4/TIP60, cooperates with the C. elegans MLL-like complex in the attenuation of RAS signalling. Critically, we show that both complexes regulate a common novel target and attenuator of RAS signalling, AJM-1 (Apical Junction Molecule-1). Therefore, the C. elegans MLL-like complex cooperates with the NuA4/TIP60 complex to regulate the expression of a novel effector, AJM-1.
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Affiliation(s)
- Kate Fisher
- Faculty of Life Sciences, University of Manchester, Michael Smith Building, Oxford Road, Manchester, M13 9PT, UK
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Phosphatome profiling reveals PTPN2, PTPRJ and PTEN as potent negative regulators of PKB/Akt activation in Ras-mutated cancer cells. Biochem J 2010; 426:65-72. [PMID: 19922411 DOI: 10.1042/bj20091413] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Oncogenic Ras mutations render the protein constitutively active and promote tumorigenesis via chronic stimulation of effector pathways. In A549 lung adenocarcinoma approx. 50% of the total Ras population is constitutively active, yet these cells display only weak activation of the effectors: ERK1/2 (extracellular-signal-regulated kinase 1/2) and Akt. In order to identify key negative regulators of oncogenic Ras signalling we performed a phosphatome RNAi (RNA interference) screen in A549 cells and ranked their effects on phosphorylation of Ser473 of Akt. As expected, the tumour suppressor PTEN (phosphatase and tensin homologue deleted on chromosome 10) emerged as a leading hit: knockdown elevated Akt activation to 70% of maximal generated by acute EGF (epidermal growth factor) stimulation. Importantly, we identified other phosphatases with similar potencies including PTPN2 (T-cell protein tyrosine phosphatase; also known as TC-PTP) and PTPRJ (protein tyrosine phosphatase receptor type J; also known as DEP-1/CD148). Potentiation of Akt phosphorylation by knockdown of PTEN or PTPRJ was contingent on the presence of oncogenic K-Ras. Our data reveal a synergy between oncogene function and the loss of a tumour suppressor within the same pathway that was necessary for full effector activation since each alone failed to elicit significant Akt phosphorylation. Taken together, these data reveal potent regulators of Akt signalling which contribute to ameliorating the consequences of oncogenic K-Ras activity.
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