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dos Santos A, Ouellete G, Diorio C, Elowe S, Durocher F. Knockdown of CKAP2 Inhibits Proliferation, Migration, and Aggregate Formation in Aggressive Breast Cancer. Cancers (Basel) 2022; 14:cancers14153759. [PMID: 35954424 PMCID: PMC9367390 DOI: 10.3390/cancers14153759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2022] [Revised: 07/28/2022] [Accepted: 07/29/2022] [Indexed: 11/26/2022] Open
Abstract
Simple Summary Cancer is a complex disease where cells grow and divide in an uncontrolled manner. It is well established that its development and progression involve major alterations in the activity of mitotic regulators. In order to improve our understanding of the contribution of cell-cycle progression defects to the development of disease, the aim of this study is to identify genes relevant to the proper progression of mitosis that are deregulated in breast cancer. Our findings identified CKAP2 as an important mitotic regulator in BC tumors. Moreover, in vitro experiments showed that gene silencing of CKAP2 blocked cell growth, cell migration, and formation of cell aggregates. These results demonstrated the important role of CKAP2 in breast cancer tumor formation. Abstract Loss of mitotic regulation is commonly observed in cancer and is a major cause of whole-chromosome aneuploidy. The identification of genes that play a role in the proper progression of mitosis can help us to understand the development and evolution of this disease. Here, we generated a list of proteins implicated in mitosis that we used to probe a patient-derived breast cancer (BC) continuum gene-expression dataset generated by our group by human transcriptome analysis of breast lesions of varying aggressiveness (from normal to invasive). We identified cytoskeleton-associated protein 2 (CKAP2) as an important mitotic regulator in invasive BC. The results showed that CKAP2 is overexpressed in invasive BC tumors when compared with normal tissues, and highly expressed in all BC subtypes. Higher expression of CKAP2 is also related to a worse prognosis in overall survival and relapse-free survival in estrogen receptor (ER)-positive and human epidermal growth factor receptor type 2 (HER2)-negative BC patients. Knockdown of CKAP2 in SKBR3 cells impaired cell proliferation and cell migration and reduced aggregate formation in a 3D culture. Our results show the important role of CKAP2 in BC tumorigenesis, and its potential utility as a prognostic marker in BC.
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Affiliation(s)
- Alexsandro dos Santos
- Département de Médecine Moléculaire, Faculté de Médecine, Université Laval, Québec City, QC G1V 0A6, Canada; (A.d.S.); (G.O.)
- Centre de Recherche sur le Cancer, CHU de Québec-Université Laval, Québec City, QC G1V 4G2, Canada;
- PROTEO-Regroupement Québécois de Recherche sur la Fonction, L’ingénierie et les Applications des Protéines, Québec City, QC G1V 0A6, Canada
| | - Geneviève Ouellete
- Département de Médecine Moléculaire, Faculté de Médecine, Université Laval, Québec City, QC G1V 0A6, Canada; (A.d.S.); (G.O.)
- Centre de Recherche sur le Cancer, CHU de Québec-Université Laval, Québec City, QC G1V 4G2, Canada;
| | - Caroline Diorio
- Centre de Recherche sur le Cancer, CHU de Québec-Université Laval, Québec City, QC G1V 4G2, Canada;
- Département de Médecine Sociale et Préventive, Faculté de Médecine, Université Laval, Québec City, QC G1V 0A6, Canada
| | - Sabine Elowe
- Centre de Recherche sur le Cancer, CHU de Québec-Université Laval, Québec City, QC G1V 4G2, Canada;
- PROTEO-Regroupement Québécois de Recherche sur la Fonction, L’ingénierie et les Applications des Protéines, Québec City, QC G1V 0A6, Canada
- Département de Pédiatrie, Faculté de Médecine, Université Laval et le Centre de recherche sur le Cancer de l’Université Laval, Québec City, QC G1R 2J6, Canada
- Correspondence: (S.E.); (F.D.)
| | - Francine Durocher
- Département de Médecine Moléculaire, Faculté de Médecine, Université Laval, Québec City, QC G1V 0A6, Canada; (A.d.S.); (G.O.)
- Centre de Recherche sur le Cancer, CHU de Québec-Université Laval, Québec City, QC G1V 4G2, Canada;
- Correspondence: (S.E.); (F.D.)
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Banerjee SL, Lessard F, Chartier FJM, Jacquet K, Osornio-Hernandez AI, Teyssier V, Ghani K, Lavoie N, Lavoie JN, Caruso M, Laprise P, Elowe S, Lambert JP, Bisson N. EPH receptor tyrosine kinases phosphorylate the PAR-3 scaffold protein to modulate downstream signaling networks. Cell Rep 2022; 40:111031. [PMID: 35793621 DOI: 10.1016/j.celrep.2022.111031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2020] [Revised: 04/26/2022] [Accepted: 06/13/2022] [Indexed: 11/03/2022] Open
Abstract
EPH receptors (EPHRs) constitute the largest family among receptor tyrosine kinases in humans. They are mainly involved in short-range cell-cell communication events that regulate cell adhesion, migration, and boundary formation. However, the molecular mechanisms by which EPHRs control these processes are less understood. To address this, we unravel EPHR-associated complexes under native conditions using mass-spectrometry-based BioID proximity labeling. We obtain a composite proximity network from EPHA4, -B2, -B3, and -B4 that comprises 395 proteins, most of which were not previously linked to EPHRs. We examine the contribution of several BioID-identified candidates via loss-of-function in an EPHR-dependent cell-segregation assay. We find that the signaling scaffold PAR-3 is required for cell sorting and that EPHRs directly phosphorylate PAR-3. We also delineate a signaling complex involving the C-terminal SRC kinase (CSK), whose recruitment to PAR-3 is dependent on EPHR signals. Our work describes signaling networks by which EPHRs regulate cellular phenotypes.
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Affiliation(s)
- Sara L Banerjee
- Centre de recherche du Centre Hospitalier Universitaire (CHU) de Quebec-Université Laval, Division Oncologie, Québec, QC, Canada; Centre de recherche sur le cancer de l'Université Laval, Québec, QC, Canada; PROTEO-Quebec Network for Research on Protein Function, Engineering, and Applications, Québec, QC, Canada
| | - Frédéric Lessard
- Centre de recherche du Centre Hospitalier Universitaire (CHU) de Quebec-Université Laval, Division Oncologie, Québec, QC, Canada; Centre de recherche sur le cancer de l'Université Laval, Québec, QC, Canada; PROTEO-Quebec Network for Research on Protein Function, Engineering, and Applications, Québec, QC, Canada
| | - François J M Chartier
- Centre de recherche du Centre Hospitalier Universitaire (CHU) de Quebec-Université Laval, Division Oncologie, Québec, QC, Canada; Centre de recherche sur le cancer de l'Université Laval, Québec, QC, Canada; PROTEO-Quebec Network for Research on Protein Function, Engineering, and Applications, Québec, QC, Canada
| | - Kévin Jacquet
- Centre de recherche du Centre Hospitalier Universitaire (CHU) de Quebec-Université Laval, Division Oncologie, Québec, QC, Canada; Centre de recherche sur le cancer de l'Université Laval, Québec, QC, Canada
| | - Ana I Osornio-Hernandez
- Centre de recherche du Centre Hospitalier Universitaire (CHU) de Quebec-Université Laval, Division Oncologie, Québec, QC, Canada; Centre de recherche sur le cancer de l'Université Laval, Québec, QC, Canada; PROTEO-Quebec Network for Research on Protein Function, Engineering, and Applications, Québec, QC, Canada
| | - Valentine Teyssier
- Centre de recherche du Centre Hospitalier Universitaire (CHU) de Quebec-Université Laval, Division Oncologie, Québec, QC, Canada; Centre de recherche sur le cancer de l'Université Laval, Québec, QC, Canada; PROTEO-Quebec Network for Research on Protein Function, Engineering, and Applications, Québec, QC, Canada
| | - Karim Ghani
- Centre de recherche du Centre Hospitalier Universitaire (CHU) de Quebec-Université Laval, Division Oncologie, Québec, QC, Canada; Centre de recherche sur le cancer de l'Université Laval, Québec, QC, Canada
| | - Noémie Lavoie
- Centre de recherche du Centre Hospitalier Universitaire (CHU) de Quebec-Université Laval, Division Oncologie, Québec, QC, Canada; Centre de recherche sur le cancer de l'Université Laval, Québec, QC, Canada; PROTEO-Quebec Network for Research on Protein Function, Engineering, and Applications, Québec, QC, Canada
| | - Josée N Lavoie
- Centre de recherche du Centre Hospitalier Universitaire (CHU) de Quebec-Université Laval, Division Oncologie, Québec, QC, Canada; Centre de recherche sur le cancer de l'Université Laval, Québec, QC, Canada; Department of Molecular Biology, Medical Biochemistry and Pathology, Université Laval, Québec, QC, Canada
| | - Manuel Caruso
- Centre de recherche du Centre Hospitalier Universitaire (CHU) de Quebec-Université Laval, Division Oncologie, Québec, QC, Canada; Centre de recherche sur le cancer de l'Université Laval, Québec, QC, Canada; Department of Molecular Biology, Medical Biochemistry and Pathology, Université Laval, Québec, QC, Canada
| | - Patrick Laprise
- Centre de recherche du Centre Hospitalier Universitaire (CHU) de Quebec-Université Laval, Division Oncologie, Québec, QC, Canada; Centre de recherche sur le cancer de l'Université Laval, Québec, QC, Canada; Department of Molecular Biology, Medical Biochemistry and Pathology, Université Laval, Québec, QC, Canada
| | - Sabine Elowe
- Centre de recherche du Centre Hospitalier Universitaire (CHU) de Quebec-Université Laval, Division Oncologie, Québec, QC, Canada; Centre de recherche sur le cancer de l'Université Laval, Québec, QC, Canada; PROTEO-Quebec Network for Research on Protein Function, Engineering, and Applications, Québec, QC, Canada; Department of Pediatrics, Université Laval, Québec, QC, Canada
| | - Jean-Philippe Lambert
- Centre de recherche sur le cancer de l'Université Laval, Québec, QC, Canada; Department of Molecular Medicine, Université Laval, Québec, QC, Canada; Centre de recherche en données massives de l'Université Laval, Québec, QC, Canada; Centre de recherche du Centre Hospitalier Universitaire (CHU) de Quebec-Université Laval, Division Endocrinologie-néphrologie, Québec, QC, Canada
| | - Nicolas Bisson
- Centre de recherche du Centre Hospitalier Universitaire (CHU) de Quebec-Université Laval, Division Oncologie, Québec, QC, Canada; Centre de recherche sur le cancer de l'Université Laval, Québec, QC, Canada; PROTEO-Quebec Network for Research on Protein Function, Engineering, and Applications, Québec, QC, Canada; Department of Molecular Biology, Medical Biochemistry and Pathology, Université Laval, Québec, QC, Canada.
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Prifti DK, Lauzier A, Elowe S. A commercial ARHGEF17/TEM4 antibody cross-reacts with Nuclear Mitotic Apparatus protein 1 (NuMA). PLoS One 2022; 17:e0268848. [PMID: 35776709 PMCID: PMC9249204 DOI: 10.1371/journal.pone.0268848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 05/20/2022] [Indexed: 11/18/2022] Open
Abstract
The Rho family Guanine nucleotide exchange factor (GEF) ARHGEF17 (also known as TEM4) is a large protein with only 3 annotated regions: an N-terminal actin-binding domain, a Rho-specific dbl homology (DH)- pleckstrin homology (PH) type GEF domain and a seven bladed β propeller fold at the C-terminus with unknown function. TEM4 has been implicated in numerous activities that rely on regulation of the cytoskeleton including cell migration, cell-cell junction formation and the spindle assembly checkpoint during mitosis. Here we have assessed the specificity of a TEM4 polyclonal antibody that has been commonly used as a Western blotting and immunocytochemistry probe for TEM4 in mammalian cells. We find that this antibody, in addition to its intended target, cross-reacts with the Nuclear Mitotic Apparatus Protein 1 (NuMA) in Western blotting and immunoprecipitation, and detects NuMA preferentially in immunocytochemistry. This cross-reactivity, with an abundant chromatin- and mitotic spindle-associated factor, is likely to affect the interpretation of experiments that make use of this antibody probe, in particular by immunocytochemistry and immunoprecipitation.
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Affiliation(s)
- Diogjena Katerina Prifti
- Programme en Biologie Cellulaire et Moléculaire, Faculté de Médicine Université Laval, Québec, Québec, Canada
- Centre de Recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Axe de Réproduction, Santé de la Mère et de l’enfant, Québec, Québec, Canada
- PROTEO-Regroupement Québécois de Recherche sur la Fonction, l’ingénierie et les Applications des Protéines, Québec, Québec, Canada
| | - Annie Lauzier
- Centre de Recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Axe de Réproduction, Santé de la Mère et de l’enfant, Québec, Québec, Canada
| | - Sabine Elowe
- Centre de Recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Axe de Réproduction, Santé de la Mère et de l’enfant, Québec, Québec, Canada
- PROTEO-Regroupement Québécois de Recherche sur la Fonction, l’ingénierie et les Applications des Protéines, Québec, Québec, Canada
- Département de Pédiatrie, Faculté de Médicine, Université Laval et le Centre de Recherche sur le Cancer de l’Université Laval, Québec, Québec, Canada
- * E-mail:
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4
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Gama Braga L, Garand C, Elowe S. Considerations for studying phosphorylation of the mitotic checkpoint pseudokinase BUBR1. Methods Enzymol 2022; 667:507-534. [PMID: 35525552 DOI: 10.1016/bs.mie.2022.03.045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Budding uninhibited by benzimidazole 1-related protein 1 (BUBR1) is a mitotic checkpoint (better known as the spindle assembly checkpoint) protein that forms part of an inhibitory complex required to delay mitosis when errors occur in the attachment between chromosomes and the mitotic spindle. If these errors remain uncorrected, it could result in unequal distribution of genetic material to each of the nascent daughter cells, leading to potentially disastrous consequences at both the cellular and organismal level. In some higher eukaryotes including vertebrates, BUBR1 has a C-terminal kinase fold that is largely thought to be inactive, whereas in many species this domain has been lost through evolution and the truncated protein is known as mitotic arrest deficient 3 (MAD3). Here we present advice and practical considerations for the design of experiments, their analysis and interpretation to study the functions of the vertebrate BUBR1 during mitosis with emphasis on analysis implicating the pseudokinase domain.
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Affiliation(s)
- Luciano Gama Braga
- Biologie Cellulaire et Moléculaire, Faculté de Médicine, Université Laval, Québec, QC, Canada; Centre de Recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Axe de Reproduction, Santé de la Mère et de l'Enfant, Québec, QC, Canada; PROTEO-Regroupement Québécois de Recherche sur la Fonction, l'Ingénierie et les Applications des Protéines, Québec, QC, Canada; Département de Pédiatire, Faculté de Médicine, Université Laval et le Centre de Recherche sur le Cancer de l'Université Laval, Québec, QC, Canada
| | - Chantal Garand
- Centre de Recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Axe de Reproduction, Santé de la Mère et de l'Enfant, Québec, QC, Canada; PROTEO-Regroupement Québécois de Recherche sur la Fonction, l'Ingénierie et les Applications des Protéines, Québec, QC, Canada
| | - Sabine Elowe
- Biologie Cellulaire et Moléculaire, Faculté de Médicine, Université Laval, Québec, QC, Canada; Centre de Recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Axe de Reproduction, Santé de la Mère et de l'Enfant, Québec, QC, Canada; PROTEO-Regroupement Québécois de Recherche sur la Fonction, l'Ingénierie et les Applications des Protéines, Québec, QC, Canada; Département de Pédiatire, Faculté de Médicine, Université Laval et le Centre de Recherche sur le Cancer de l'Université Laval, Québec, QC, Canada.
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5
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Elowe S, Bolanos-Garcia VM. The spindle checkpoint proteins BUB1 and BUBR1: (SLiM)ming down to the basics. Trends Biochem Sci 2022; 47:352-366. [DOI: 10.1016/j.tibs.2022.01.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 01/19/2022] [Accepted: 01/20/2022] [Indexed: 12/16/2022]
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6
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Villot R, Poirier A, Devillers R, Kolnoguz A, Elowe S, Manem VSK, Joubert P, Mallette FA, Laplante M. ZNF768: controlling cellular senescence and proliferation with ten fingers. Mol Cell Oncol 2021; 8:1985930. [PMID: 35419475 PMCID: PMC8997246 DOI: 10.1080/23723556.2021.1985930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
We recently identified Zinc-finger protein 768 (ZNF768) as a novel transcription factor controlling cell fate decision downstream of Rat sarcoma virus (RAS). We showed that ZNF768 depletion impairs cell cycle progression and triggers cellular senescence, while its overexpression allows cells to bypass oncogene-induced senescence. Elevated ZNF768 levels is common in tumors, suggesting that ZNF768 may help to escape cellular senescence, sustain proliferation and promote malignant transformation. Here, we discuss these recent findings and highlight key questions emerging from our work.
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Affiliation(s)
- Romain Villot
- Centre de Recherche de l’Institut Universitaire de Cardiologie et de Pneumologie de Québec (CRIUCPQ), Faculté de Médecine, Université Laval, Québec, QC, Canada
- Centre de Recherche sur le Cancer de l’Université Laval, Université Laval, Québec, QC, Canada
| | - Audrey Poirier
- Centre de Recherche de l’Institut Universitaire de Cardiologie et de Pneumologie de Québec (CRIUCPQ), Faculté de Médecine, Université Laval, Québec, QC, Canada
- Centre de Recherche sur le Cancer de l’Université Laval, Université Laval, Québec, QC, Canada
| | - Romain Devillers
- Centre de Recherche de l’Institut Universitaire de Cardiologie et de Pneumologie de Québec (CRIUCPQ), Faculté de Médecine, Université Laval, Québec, QC, Canada
- Centre de Recherche sur le Cancer de l’Université Laval, Université Laval, Québec, QC, Canada
- Centre de Recherche du CHU de Québec, Université Laval, Québec, QC, Canada
| | - Aliona Kolnoguz
- Centre de Recherche de l’Institut Universitaire de Cardiologie et de Pneumologie de Québec (CRIUCPQ), Faculté de Médecine, Université Laval, Québec, QC, Canada
- Centre de Recherche sur le Cancer de l’Université Laval, Université Laval, Québec, QC, Canada
| | - Sabine Elowe
- Centre de Recherche sur le Cancer de l’Université Laval, Université Laval, Québec, QC, Canada
- Centre de Recherche du CHU de Québec, Université Laval, Québec, QC, Canada
- Département de Pédiatrie, Faculté de Médecine, Université Laval, Québec, QC, Canada
| | - Venkata S. K. Manem
- Centre de Recherche de l’Institut Universitaire de Cardiologie et de Pneumologie de Québec (CRIUCPQ), Faculté de Médecine, Université Laval, Québec, QC, Canada
- Faculty of Pharmacy, Université Laval, Québec, QC, Canada
| | - Philippe Joubert
- Centre de Recherche de l’Institut Universitaire de Cardiologie et de Pneumologie de Québec (CRIUCPQ), Faculté de Médecine, Université Laval, Québec, QC, Canada
- Centre de Recherche sur le Cancer de l’Université Laval, Université Laval, Québec, QC, Canada
| | - Frédérick A. Mallette
- Département de Médecine, Université de Montréal, Montréal, QC, Canada
- Chromatin Structure and Cellular Senescence Research Unit, Maisonneuve-Rosemont Hospital Research Centre, Université de Montréal, Montréal, QC, Canada
- Département de Biochimie et Médecine Moléculaire, Université de Montréal, Montréal, QC, Canada
| | - Mathieu Laplante
- Centre de Recherche de l’Institut Universitaire de Cardiologie et de Pneumologie de Québec (CRIUCPQ), Faculté de Médecine, Université Laval, Québec, QC, Canada
- Centre de Recherche sur le Cancer de l’Université Laval, Université Laval, Québec, QC, Canada
- Département de Médecine, Faculté de Médecine, Université Laval, Québec, QC, Canada
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Paré G, Vitry J, Merchant ML, Vaillancourt M, Murru A, Shen Y, Elowe S, Lahoud MH, Naccache PH, McLeish KR, Fernandes MJ. The Inhibitory Receptor CLEC12A Regulates PI3K-Akt Signaling to Inhibit Neutrophil Activation and Cytokine Release. Front Immunol 2021; 12:650808. [PMID: 34234773 PMCID: PMC8256872 DOI: 10.3389/fimmu.2021.650808] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 05/21/2021] [Indexed: 12/25/2022] Open
Abstract
The myeloid inhibitory C-type lectin receptor CLEC12A limits neutrophil activation, pro-inflammatory pathways and disease in mouse models of inflammatory arthritis by a molecular mechanism that remains poorly understood. We addressed how CLEC12A-mediated inhibitory signaling counteracts activating signaling by cross-linking CLEC12A in human neutrophils. CLEC12A cross-linking induced its translocation to flotillin-rich membrane domains where its ITIM was phosphorylated in a Src-dependent manner. Phosphoproteomic analysis identified candidate signaling molecules regulated by CLEC12A that include MAPKs, phosphoinositol kinases and members of the JAK-STAT pathway. Stimulating neutrophils with uric acid crystals, the etiological agent of gout, drove the hyperphosphorylation of p38 and Akt. Ultimately, one of the pathways through which CLEC12A regulates uric acid crystal-stimulated release of IL-8 by neutrophils is through a p38/PI3K-Akt signaling pathway. In summary this work defines early molecular events that underpin CLEC12A signaling in human neutrophils to modulate cytokine synthesis. Targeting this pathway could be useful therapeutically to dampen inflammation.
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Affiliation(s)
- Guillaume Paré
- Division of Infectious Diseases and Immunology, Laval University, Centres Hospitaliers Universitaires (CHU) de Québec Research Center, Québec, QC, Canada
| | - Julien Vitry
- Division of Infectious Diseases and Immunology, Laval University, Centres Hospitaliers Universitaires (CHU) de Québec Research Center, Québec, QC, Canada.,Department of Microbiology and Immunology, Faculty of Medicine, Laval University, CHU de Québec Research Center, Québec, QC, Canada
| | - Michael L Merchant
- Department of Medicine, University of Louisville School of Medicine, Louisville, KY, United States
| | - Myriam Vaillancourt
- Division of Infectious Diseases and Immunology, Laval University, Centres Hospitaliers Universitaires (CHU) de Québec Research Center, Québec, QC, Canada
| | - Andréa Murru
- Division of Infectious Diseases and Immunology, Laval University, Centres Hospitaliers Universitaires (CHU) de Québec Research Center, Québec, QC, Canada.,Department of Microbiology and Immunology, Faculty of Medicine, Laval University, CHU de Québec Research Center, Québec, QC, Canada
| | - Yunyun Shen
- Division of Infectious Diseases and Immunology, Laval University, Centres Hospitaliers Universitaires (CHU) de Québec Research Center, Québec, QC, Canada.,Department of Microbiology and Immunology, Faculty of Medicine, Laval University, CHU de Québec Research Center, Québec, QC, Canada
| | - Sabine Elowe
- Department of Pediatrics, Faculty of Medicine, Laval University, CHU de Québec Research Center, Québec, QC, Canada.,Reproduction, Mother and Youth Health Division, Laval University, CHU de Québec Research Center, Québec, QC, Canada
| | - Mireille H Lahoud
- Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Paul H Naccache
- Division of Infectious Diseases and Immunology, Laval University, Centres Hospitaliers Universitaires (CHU) de Québec Research Center, Québec, QC, Canada.,Department of Microbiology and Immunology, Faculty of Medicine, Laval University, CHU de Québec Research Center, Québec, QC, Canada
| | - Kenneth R McLeish
- Department of Medicine, University of Louisville School of Medicine, Louisville, KY, United States
| | - Maria J Fernandes
- Division of Infectious Diseases and Immunology, Laval University, Centres Hospitaliers Universitaires (CHU) de Québec Research Center, Québec, QC, Canada.,Department of Microbiology and Immunology, Faculty of Medicine, Laval University, CHU de Québec Research Center, Québec, QC, Canada
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8
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Gama Braga L, Prifti DK, Garand C, Saini PK, Elowe S. A quantitative and semiautomated method for determining misaligned and lagging chromosomes during mitosis. Mol Biol Cell 2021; 32:880-891. [PMID: 33085580 PMCID: PMC8108530 DOI: 10.1091/mbc.e20-09-0585] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 10/08/2020] [Accepted: 10/08/2020] [Indexed: 01/21/2023] Open
Abstract
Accurate chromosome alignment at metaphase facilitates the equal segregation of sister chromatids to each of the nascent daughter cells. Lack of proper metaphase alignment is an indicator of defective chromosome congression and aberrant kinetochore-microtubule attachments which in turn promotes chromosome missegregation and aneuploidy, hallmarks of cancer. Tools to sensitively, accurately, and quantitatively measure chromosome alignment at metaphase will facilitate understanding of the contribution of chromosome segregation errors to the development of aneuploidy. In this work, we have developed and validated a method based on analytical geometry to measure several indicators of chromosome misalignment. We generated semiautomated and flexible ImageJ2/Fiji pipelines to quantify kinetochore misalignment at metaphase plates as well as lagging chromosomes at anaphase. These tools will ultimately allow sensitive and systematic quantitation of these chromosome segregation defects in cells undergoing mitosis.
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Affiliation(s)
- Luciano Gama Braga
- Programme en Biologie cellulaire et moléculaire, Faculté de Médicine Université Laval, Québec, QC G1V 0A6, Canada
- Centre de recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Axe de réproduction, santé de la mère et de l’enfant, Québec, QC G1V 4G2, Canada
- PROTEO-regroupement québécois de recherche sur la fonction, l’ingénierie et les applications des protéines, Québec, QC G1V 0A6, Canada
| | - Diogjena Katerina Prifti
- Programme en Biologie cellulaire et moléculaire, Faculté de Médicine Université Laval, Québec, QC G1V 0A6, Canada
- Centre de recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Axe de réproduction, santé de la mère et de l’enfant, Québec, QC G1V 4G2, Canada
- PROTEO-regroupement québécois de recherche sur la fonction, l’ingénierie et les applications des protéines, Québec, QC G1V 0A6, Canada
| | - Chantal Garand
- Centre de recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Axe de réproduction, santé de la mère et de l’enfant, Québec, QC G1V 4G2, Canada
| | - Pawan Kumar Saini
- Programme en Médicine moléculaire, Faculté de Médicine Université Laval, Québec, QC G1V 0A6, Canada
- Centre de recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Axe de réproduction, santé de la mère et de l’enfant, Québec, QC G1V 4G2, Canada
- PROTEO-regroupement québécois de recherche sur la fonction, l’ingénierie et les applications des protéines, Québec, QC G1V 0A6, Canada
| | - Sabine Elowe
- Centre de recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Axe de réproduction, santé de la mère et de l’enfant, Québec, QC G1V 4G2, Canada
- PROTEO-regroupement québécois de recherche sur la fonction, l’ingénierie et les applications des protéines, Québec, QC G1V 0A6, Canada
- Département de Pédiatire, Faculté de Médicine, Université Laval et le Centre de recherche sur le cancer de l’Université Laval, Québec, QC G1R 2J6, Canada
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9
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Elowe S. Adventures of the undead at kinetochores. Mol Cell Oncol 2021; 8:1876511. [PMID: 33860079 DOI: 10.1080/23723556.2021.1876511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
At the metaphase-to-anaphase transition, phosphatase activity feeds back to reverse early mitotic phosphorylation events. Our recent work indicates that the pseudokinase domain of the spindle checkpoint protein BUB1 (Budding Uninhibited by Benzimidazoles 1) mitotic checkpoint serine/threonine kinase B (BUB1B, BUBR1) maintains kinase-phosphatase balance at the outer kinetochore during mitotic exit.
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Affiliation(s)
- Sabine Elowe
- Axe de reproduction, santé de la mère et de l'enfant, Centre de recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Québec, QC, Canada.,PROTEO-regroupement québécois de recherche sur la fonction, l'ingénierie et les applications des protéines, Québec, QC, Canada.,Département de Pédiatrie, Faculté de Médicine, Université Laval et le Centre de recherche sur le cancer de l'Université Laval, Québec, QC, Canada
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10
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Dos Santos A, Elowe S. Moonlighting at the Centrosome: RXRα Turns to Plk1. Dev Cell 2020; 55:672-674. [PMID: 33352140 DOI: 10.1016/j.devcel.2020.11.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
One of the hardest working mitotic proteins, Polo-like kinase 1 (PLK1), functions at mitotic entry, cytokinesis, and many steps in between. In this issue, Xie et al. (2020) describe a centrosome-specific interaction between PLK1 and Retinoid X Receptor-α and they test selective inhibition of this interaction as an anti-mitotic cancer therapy.
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Affiliation(s)
- Alexsandro Dos Santos
- Programme en Médicine Moléculaire, Faculté de Médicine, Université Laval, Québec, QC G1V 0A6, Canada; Centre de recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Axe de reproduction, santé de la mère et de l'enfant, Québec, QC G1V 4G2, Canada; PROTEO-regroupement québécois de recherche sur la fonction, l'ingénierie et les applications des protéines, Québec, QC G1V 0A6, Canada
| | - Sabine Elowe
- Centre de recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Axe de reproduction, santé de la mère et de l'enfant, Québec, QC G1V 4G2, Canada; PROTEO-regroupement québécois de recherche sur la fonction, l'ingénierie et les applications des protéines, Québec, QC G1V 0A6, Canada; Département de Pédiatire, Faculté de Médicine, Université Laval et le Centre de recherche sur le cancer de l'Université Laval, Québec, QC G1R 2J6, Canada.
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11
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Elowe S. Editorial: Novel Insights Into the Multifaceted Mitotic Kinases. Front Cell Dev Biol 2019; 7:51. [PMID: 31024912 PMCID: PMC6465794 DOI: 10.3389/fcell.2019.00051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Accepted: 03/19/2019] [Indexed: 11/13/2022] Open
Affiliation(s)
- Sabine Elowe
- Department of Pediatrics, Faculty of Medicine, Axe of Reproduction, Mother and Infant Health, Université Laval, Quebec City, QC, Canada.,Research Center of the CHU de Québec, Quebec City, QC, Canada
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12
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Boutchueng-Djidjou M, Belleau P, Bilodeau N, Fortier S, Bourassa S, Droit A, Elowe S, Faure RL. A type 2 diabetes disease module with a high collective influence for Cdk2 and PTPLAD1 is localized in endosomes. PLoS One 2018; 13:e0205180. [PMID: 30300385 PMCID: PMC6177195 DOI: 10.1371/journal.pone.0205180] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Accepted: 09/20/2018] [Indexed: 01/19/2023] Open
Abstract
Despite the identification of many susceptibility genes our knowledge of the underlying mechanisms responsible for complex disease remains limited. Here, we identified a type 2 diabetes disease module in endosomes, and validate it for functional relevance on selected nodes. Using hepatic Golgi/endosomes fractions, we established a proteome of insulin receptor-containing endosomes that allowed the study of physical protein interaction networks on a type 2 diabetes background. The resulting collated network is formed by 313 nodes and 1147 edges with a topology organized around a few major hubs with Cdk2 displaying the highest collective influence. Overall, 88% of the nodes are associated with the type 2 diabetes genetic risk, including 101 new candidates. The Type 2 diabetes module is enriched with cytoskeleton and luminal acidification–dependent processes that are shared with secretion-related mechanisms. We identified new signaling pathways driven by Cdk2 and PTPLAD1 whose expression affects the association of the insulin receptor with TUBA, TUBB, the actin component ACTB and the endosomal sorting markers Rab5c and Rab11a. Therefore, the interactome of internalized insulin receptors reveals the presence of a type 2 diabetes disease module enriched in new layers of feedback loops required for insulin signaling, clearance and islet biology.
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Affiliation(s)
- Martial Boutchueng-Djidjou
- Départment of Pediatrics, Faculty of Medicine, Université Laval, Centre de Recherche du CHU de Québec, Québec city, Canada
| | - Pascal Belleau
- Plateforme Protéomique de l’Est du Québec, Université Laval. Université Laval, Québec, QC, Canada
| | - Nicolas Bilodeau
- Départment of Pediatrics, Faculty of Medicine, Université Laval, Centre de Recherche du CHU de Québec, Québec city, Canada
| | - Suzanne Fortier
- Départment of Pediatrics, Faculty of Medicine, Université Laval, Centre de Recherche du CHU de Québec, Québec city, Canada
| | - Sylvie Bourassa
- Plateforme Protéomique de l’Est du Québec, Université Laval. Université Laval, Québec, QC, Canada
| | - Arnaud Droit
- Plateforme Protéomique de l’Est du Québec, Université Laval. Université Laval, Québec, QC, Canada
| | - Sabine Elowe
- Départment of Pediatrics, Faculty of Medicine, Université Laval, Centre de Recherche du CHU de Québec, Québec city, Canada
| | - Robert L. Faure
- Départment of Pediatrics, Faculty of Medicine, Université Laval, Centre de Recherche du CHU de Québec, Québec city, Canada
- * E-mail:
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13
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Jacquet K, Banerjee SL, Chartier FJM, Elowe S, Bisson N. Proteomic Analysis of NCK1/2 Adaptors Uncovers Paralog-specific Interactions That Reveal a New Role for NCK2 in Cell Abscission During Cytokinesis. Mol Cell Proteomics 2018; 17:1979-1990. [PMID: 30002203 DOI: 10.1074/mcp.ra118.000689] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2018] [Revised: 07/11/2018] [Indexed: 12/31/2022] Open
Abstract
Signals from cell surface receptors are often relayed via adaptor proteins. NCK1 and NCK2 are Src-Homology (SH) 2 and 3 domain adaptors that regulate processes requiring a remodeling of the actin cytoskeleton. Evidence from gene inactivation in mouse suggests that NCK1 and NCK2 are functionally redundant, although recent reports support the idea of unique functions for NCK1 and NCK2. We sought to examine this question further by delineating NCK1- and NCK2-specific signaling networks. We used both affinity purification-mass spectrometry and BioID proximity labeling to identify NCK1/2 signaling networks comprised of 98 proteins. Strikingly, we found 30 proteins restricted to NCK1 and 28 proteins specifically associated with NCK2, suggesting differences in their function. We report that Nck2 -/-, but not Nck1 -/- mouse embryo fibroblasts (MEFs) are multinucleated and display extended protrusions reminiscent of intercellular bridges, which correlate with an extended time spent in cytokinesis as well as a failure of a significant proportion of cells to complete abscission. Our data also show that the midbody of NCK2-deficient cells is not only increased in length, but also altered in composition, as judged by the mislocalization of AURKB, PLK1 and ECT2. Finally, we show that NCK2 function during cytokinesis requires its SH2 domain. Taken together, our data delineate the first high-confidence interactome for NCK1/2 adaptors and highlight several proteins specifically associated with either protein. Thus, contrary to what is generally accepted, we demonstrate that NCK1 and NCK2 are not completely redundant, and shed light on a previously uncharacterized function for the NCK2 adaptor protein in cell division.
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Affiliation(s)
- Kévin Jacquet
- From the ‡Centre de recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Axe Oncologie, Québec G1R 2J6, QC, Canada.,§Centre de recherche sur le cancer de l'Université Laval, Québec G1R 2J6, QC, Canada.,¶PROTEO-Quebec Network for Research on Protein Function, Engineering, and Applications, Québec G1V 0A6, QC, Canada
| | - Sara L Banerjee
- From the ‡Centre de recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Axe Oncologie, Québec G1R 2J6, QC, Canada.,§Centre de recherche sur le cancer de l'Université Laval, Québec G1R 2J6, QC, Canada.,¶PROTEO-Quebec Network for Research on Protein Function, Engineering, and Applications, Québec G1V 0A6, QC, Canada
| | - François J M Chartier
- From the ‡Centre de recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Axe Oncologie, Québec G1R 2J6, QC, Canada.,§Centre de recherche sur le cancer de l'Université Laval, Québec G1R 2J6, QC, Canada.,¶PROTEO-Quebec Network for Research on Protein Function, Engineering, and Applications, Québec G1V 0A6, QC, Canada
| | - Sabine Elowe
- §Centre de recherche sur le cancer de l'Université Laval, Québec G1R 2J6, QC, Canada.,¶PROTEO-Quebec Network for Research on Protein Function, Engineering, and Applications, Québec G1V 0A6, QC, Canada.,‖Centre de recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Axe Reproduction, santé de la mère et de l'enfant, Québec G1V 4G2, QC, Canada.,**Department of Pediatrics, Université Laval, Québec, QC, Canada
| | - Nicolas Bisson
- From the ‡Centre de recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Axe Oncologie, Québec G1R 2J6, QC, Canada; .,§Centre de recherche sur le cancer de l'Université Laval, Québec G1R 2J6, QC, Canada.,¶PROTEO-Quebec Network for Research on Protein Function, Engineering, and Applications, Québec G1V 0A6, QC, Canada.,‡‡Department of Molecular Biology, Medical Biochemistry and Pathology, Université Laval, Québec G1V 0A6, QC, Canada
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14
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Combes G, Barysz H, Garand C, Gama Braga L, Alharbi I, Thebault P, Murakami L, Bryne DP, Stankovic S, Eyers PA, Bolanos-Garcia VM, Earnshaw WC, Maciejowski J, Jallepalli PV, Elowe S. Mps1 Phosphorylates Its N-Terminal Extension to Relieve Autoinhibition and Activate the Spindle Assembly Checkpoint. Curr Biol 2018; 28:872-883.e5. [PMID: 29502948 PMCID: PMC5863767 DOI: 10.1016/j.cub.2018.02.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 01/15/2018] [Accepted: 02/01/2018] [Indexed: 12/29/2022]
Abstract
Monopolar spindle 1 (Mps1) is a conserved apical kinase in the spindle assembly checkpoint (SAC) that ensures accurate segregation of chromosomes during mitosis. Mps1 undergoes extensive auto- and transphosphorylation, but the regulatory and functional consequences of these modifications remain unclear. Recent findings highlight the importance of intermolecular interactions between the N-terminal extension (NTE) of Mps1 and the Hec1 subunit of the NDC80 complex, which control Mps1 localization at kinetochores and activation of the SAC. Whether the NTE regulates other mitotic functions of Mps1 remains unknown. Here, we report that phosphorylation within the NTE contributes to Mps1 activation through relief of catalytic autoinhibition that is mediated by the NTE itself. Moreover, we find that this regulatory NTE function is independent of its role in Mps1 kinetochore recruitment. We demonstrate that the NTE autoinhibitory mechanism impinges most strongly on Mps1-dependent SAC functions and propose that Mps1 activation likely occurs sequentially through dimerization of a “prone-to-autophosphorylate” Mps1 conformer followed by autophosphorylation of the NTE prior to maximal kinase activation segment trans-autophosphorylation. Our observations underline the importance of autoregulated Mps1 activity in generation and maintenance of a robust SAC in human cells. Mps1 autophosphorylation at the NTE promotes activity independent of localization NTE phosphorylation relieves an NTE-dependent autoinhibition Mps1 autophosphorylation at its NTE is essential for the SAC, but not congression
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Affiliation(s)
- Guillaume Combes
- Programme in Molecular and Cellular Biology, Faculty of Medicine, Université Laval, 1050 Avenue de la Médecine, Bureau 4633, Université Laval, Québec, QC G1V0A6, Canada; Axe of Reproduction, Mother and Youth Health, Centre de Recherche du Centre Hospitalier Universitaire de Québec, Québec, QC G1V 4G2, Canada
| | - Helena Barysz
- Wellcome Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Chantal Garand
- Axe of Reproduction, Mother and Youth Health, Centre de Recherche du Centre Hospitalier Universitaire de Québec, Québec, QC G1V 4G2, Canada
| | - Luciano Gama Braga
- Programme in Molecular and Cellular Biology, Faculty of Medicine, Université Laval, 1050 Avenue de la Médecine, Bureau 4633, Université Laval, Québec, QC G1V0A6, Canada; Axe of Reproduction, Mother and Youth Health, Centre de Recherche du Centre Hospitalier Universitaire de Québec, Québec, QC G1V 4G2, Canada
| | - Ibrahim Alharbi
- Programme in Molecular and Cellular Biology, Faculty of Medicine, Université Laval, 1050 Avenue de la Médecine, Bureau 4633, Université Laval, Québec, QC G1V0A6, Canada; Axe of Reproduction, Mother and Youth Health, Centre de Recherche du Centre Hospitalier Universitaire de Québec, Québec, QC G1V 4G2, Canada
| | - Philippe Thebault
- Axe of Reproduction, Mother and Youth Health, Centre de Recherche du Centre Hospitalier Universitaire de Québec, Québec, QC G1V 4G2, Canada
| | - Luc Murakami
- Axe of Reproduction, Mother and Youth Health, Centre de Recherche du Centre Hospitalier Universitaire de Québec, Québec, QC G1V 4G2, Canada
| | - Dominic P Bryne
- Department of Biochemistry, Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK
| | - Stasa Stankovic
- Department of Biological and Medical Sciences - Faculty of Health and Life Sciences, Oxford Brookes University, Oxford OX3 0BP, UK
| | - Patrick A Eyers
- Department of Biochemistry, Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK
| | - Victor M Bolanos-Garcia
- Department of Biological and Medical Sciences - Faculty of Health and Life Sciences, Oxford Brookes University, Oxford OX3 0BP, UK
| | - William C Earnshaw
- Wellcome Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - John Maciejowski
- Molecular Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Prasad V Jallepalli
- Molecular Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Sabine Elowe
- Programme in Molecular and Cellular Biology, Faculty of Medicine, Université Laval, 1050 Avenue de la Médecine, Bureau 4633, Université Laval, Québec, QC G1V0A6, Canada; Axe of Reproduction, Mother and Youth Health, Centre de Recherche du Centre Hospitalier Universitaire de Québec, Québec, QC G1V 4G2, Canada.
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15
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Combes G, Alharbi I, Braga LG, Elowe S. Playing polo during mitosis: PLK1 takes the lead. Oncogene 2017; 36:4819-4827. [PMID: 28436952 DOI: 10.1038/onc.2017.113] [Citation(s) in RCA: 99] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 03/16/2017] [Accepted: 03/18/2017] [Indexed: 12/18/2022]
Abstract
Polo-like kinase 1 (PLK1), the prototypical member of the polo-like family of serine/threonine kinases, is a pivotal regulator of mitosis and cytokinesis in eukaryotes. Many layers of regulation have evolved to target PLK1 to different subcellular structures and to its various mitotic substrates in line with its numerous functions during mitosis. Collective work is starting to illuminate an important set of substrates for PLK1: the mitotic kinases that together ensure the fidelity of the cell division process. Amongst these, recent developments argue that PLK1 regulates the activity of the histone kinases Aurora B and Haspin to define centromere identity, of MPS1 to initiate spindle checkpoint signaling, and of BUB1 and its pseudokinase paralog BUBR1 to coordinate spindle checkpoint activation and inactivation. Here, we review the recent work describing the regulation of these kinases by PLK1. We highlight common themes throughout and argue that a major mitotic function of PLK1 is as a master regulator of these key kinases.
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Affiliation(s)
- G Combes
- Program in Molecular and Cellular biology, Faculty of Medicine, Université Laval, Quebec City, Quebec, Canada
- Axe of Reproduction, Mother and Youth Health, CHU de Québec Research Centre, Quebec City, Quebec, Canada
| | - I Alharbi
- Program in Molecular and Cellular biology, Faculty of Medicine, Université Laval, Quebec City, Quebec, Canada
- Axe of Reproduction, Mother and Youth Health, CHU de Québec Research Centre, Quebec City, Quebec, Canada
| | - L G Braga
- Program in Molecular and Cellular biology, Faculty of Medicine, Université Laval, Quebec City, Quebec, Canada
- Axe of Reproduction, Mother and Youth Health, CHU de Québec Research Centre, Quebec City, Quebec, Canada
| | - S Elowe
- Program in Molecular and Cellular biology, Faculty of Medicine, Université Laval, Quebec City, Quebec, Canada
- Axe of Reproduction, Mother and Youth Health, CHU de Québec Research Centre, Quebec City, Quebec, Canada
- Department of Pediatrics, Faculty of Medicine, Université Laval, Quebec City, Quebec, Canada
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16
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Abstract
Tyrosine phosphorylation is rare, representing only about 0.5% of phosphorylations in the cell under basal conditions. While mitogenic tyrosine kinase signaling has been extensively explored, the role of phosphotyrosine signaling across the cell cycle and in particular during mitosis is poorly understood. Two recent, independent studies tackled this question from different angles to reveal exciting new insights into the role of this modification during cell division. Caron et al. 1 exploited mitotic phosphoproteomics data sets to determine the extent of mitotic tyrosine phosphorylation, and St-Denis et al. 2 identified protein tyrosine phosphatases from all subfamilies as regulators of mitotic progression or spindle formation. These studied collectively revealed that tyrosine phosphorylation may play a more prominent and active role in mitotic progression than previously appreciated.
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Affiliation(s)
- Sabine Elowe
- a Department de Pédiatrie, Faculté de Medicine , Université Laval, Axe de Réproduction, Santé de la Mère et de l'enfant, Centre de Rechereche du CHU de Québec , Québec , QC , Canada
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17
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Caron D, Byrne DP, Thebault P, Soulet D, Landry CR, Eyers PA, Elowe S. Mitotic phosphotyrosine network analysis reveals that tyrosine phosphorylation regulates Polo-like kinase 1 (PLK1). Sci Signal 2016; 9:rs14. [PMID: 27965426 DOI: 10.1126/scisignal.aah3525] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Tyrosine phosphorylation is closely associated with cell proliferation. During the cell cycle, serine and threonine phosphorylation plays the leading role, and such phosphorylation events are most dynamic during the mitotic phase of the cell cycle. However, mitotic phosphotyrosine is not well characterized. Although a few functionally-relevant mitotic phosphotyrosine sites have been characterized, evidence suggests that this modification may be more prevalent than previously appreciated. Here, we examined tyrosine phosphorylation in mitotic human cells including those on spindle-associated proteins.? Database mining confirmed ~2000 mitotic phosphotyrosine sites, and network analysis revealed a number of subnetworks that were enriched in tyrosine-phosphorylated proteins, including components of the kinetochore or spindle and SRC family kinases. We identified Polo-like kinase 1 (PLK1), a major signaling hub in the spindle subnetwork, as phosphorylated at the conserved Tyr217 in the kinase domain. Substitution of Tyr217 with a phosphomimetic residue eliminated PLK1 activity in vitro and in cells. Further analysis showed that Tyr217 phosphorylation reduced the phosphorylation of Thr210 in the activation loop, a phosphorylation event necessary for PLK1 activity. Our data indicate that mitotic tyrosine phosphorylation regulated a key serine/threonine kinase hub in mitotic cells and suggested that spatially separating tyrosine phosphorylation events can reveal previously unrecognized regulatory events and complexes associated with specific structures of the cell cycle.
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Affiliation(s)
- Danielle Caron
- Department of Pediatrics, Faculty of Medicine, Université Laval, Centre Hospitalier Universitaire de Québec Research Center, Quebec City, Quebec G1V 4G2, Canada
| | - Dominic P Byrne
- Department of Biochemistry, Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, U.K
| | - Philippe Thebault
- Department of Pediatrics, Faculty of Medicine, Université Laval, Centre Hospitalier Universitaire de Québec Research Center, Quebec City, Quebec G1V 4G2, Canada
| | - Denis Soulet
- Department of Psychiatry et Neurosciences, Faculty of Medicine, Université Laval, Centre Hospitalier Universitaire de Québec Research Center, Quebec City, Quebec G1V 4G2, Canada
| | - Christian R Landry
- Institut de Biologie Intégrative et des Systèmes, Department of Biology, PROTEO, Université Laval, Pavillon Charles-Eugène-Marchand, 1030 Avenue de la Médecine, Quebec City, Quebec G1V 0A6, Canada
| | - Patrick A Eyers
- Department of Biochemistry, Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, U.K
| | - Sabine Elowe
- Department of Pediatrics, Faculty of Medicine, Université Laval, Centre Hospitalier Universitaire de Québec Research Center, Quebec City, Quebec G1V 4G2, Canada.
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18
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Wang LH, Yen CJ, Li TN, Elowe S, Wang WC, Wang LHC. Sgo1 is a potential therapeutic target for hepatocellular carcinoma. Oncotarget 2015; 6:2023-33. [PMID: 25638162 PMCID: PMC4385833 DOI: 10.18632/oncotarget.2764] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2014] [Accepted: 11/17/2014] [Indexed: 02/07/2023] Open
Abstract
Shugoshin-like protein 1 (Sgo1) is an essential protein in mitosis; it protects sister chromatid cohesion and thereby ensures the fidelity of chromosome separation. We found that the expression of Sgo1 mRNA was relatively low in normal tissues, but was upregulated in 82% of hepatocellular carcinoma (HCC), and correlated with elevated alpha-fetoprotein and early disease onset of HCC. The depletion of Sgo1 reduced cell viability of hepatoma cell lines including HuH7, HepG2, Hep3B, and HepaRG. Using time-lapse microscopy, we showed that hepatoma cells were delayed and ultimately die in mitosis in the absence of Sgo1. In contrast, cell viability and mitotic progression of immortalized cells were not significantly affected. Notably, mitotic cell death induced upon Sgo1 depletion was suppressed upon inhibitions of cyclin-dependent kinase-1 and Aurora kinase-B, or the depletion of mitotic arrest deficient-2. Thus, mitotic cell death induced upon Sgo1 depletion in hepatoma cells is mediated by persistent activation of the spindle assembly checkpoint. Together, these results highlight the essential role of Sgo1 in the maintenance of a proper mitotic progression in hepatoma cells and suggest that Sgo1 is a promising oncotarget for HCC.
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Affiliation(s)
- Lyu-Han Wang
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu, Taiwan
| | - Chia-Jui Yen
- Institute of Clinical Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Tian-Neng Li
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu, Taiwan
| | - Sabine Elowe
- Université Laval, Faculty of Medicine, Department of Pediatrics, and Reproduction, Perinatal Health, and Infant Health, Québec, Canada
| | - Wen-Ching Wang
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu, Taiwan
| | - Lily Hui-Ching Wang
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu, Taiwan.,Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan
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19
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Fuchs M, Luthold C, Guilbert SM, Varlet AA, Lambert H, Jetté A, Elowe S, Landry J, Lavoie JN. A Role for the Chaperone Complex BAG3-HSPB8 in Actin Dynamics, Spindle Orientation and Proper Chromosome Segregation during Mitosis. PLoS Genet 2015; 11:e1005582. [PMID: 26496431 PMCID: PMC4619738 DOI: 10.1371/journal.pgen.1005582] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Accepted: 09/16/2015] [Indexed: 02/07/2023] Open
Abstract
The co-chaperone BAG3, in complex with the heat shock protein HSPB8, plays a role in protein quality control during mechanical strain. It is part of a multichaperone complex that senses damaged cytoskeletal proteins and orchestrates their seclusion and/or degradation by selective autophagy. Here we describe a novel role for the BAG3-HSPB8 complex in mitosis, a process involving profound changes in cell tension homeostasis. BAG3 is hyperphosphorylated at mitotic entry and localizes to centrosomal regions. BAG3 regulates, in an HSPB8-dependent manner, the timely congression of chromosomes to the metaphase plate by influencing the three-dimensional positioning of the mitotic spindle. Depletion of BAG3 caused defects in cell rounding at metaphase and dramatic blebbing of the cortex associated with abnormal spindle rotations. Similar defects were observed upon silencing of the autophagic receptor p62/SQSTM1 that contributes to BAG3-mediated selective autophagy pathway. Mitotic cells depleted of BAG3, HSPB8 or p62/SQSTM1 exhibited disorganized actin-rich retraction fibres, which are proposed to guide spindle orientation. Proper spindle positioning was rescued in BAG3-depleted cells upon addition of the lectin concanavalin A, which restores cortex rigidity. Together, our findings suggest the existence of a so-far unrecognized quality control mechanism involving BAG3, HSPB8 and p62/SQSTM1 for accurate remodelling of actin-based mitotic structures that guide spindle orientation. Small heat shock proteins (sHSP/HSPB) form a diverse family of ATP-independent chaperones. Some of them protect the proteome against aggregation during stress and others regulate normal biological processes through ill-defined mechanisms. Interactions between HSPB proteins and elements of the cytoskeleton are increasingly linked to their implication in human degenerative diseases and cancer. For instance, a multichaperone complex containing HSPB8 and its co-chaperone BAG3 would maintain muscle cell integrity by promoting the autophagic clearance of damaged components within F-actin structures. Selective autophagy is a targeted protein degradation mechanism for elimination of damaged organelles and proteins. It may also regulate removal of signaling proteins from their functionally relevant sites during intense remodeling of the cytoskeleton, as it occurs during mitosis. Here, we report a novel role for HSPB8 and BAG3 during mitosis in mammalian cells that involves the autophagic receptor p62/SQSTM1. We show that a reduction of any protein within the HSPB8-BAG3-p62/SQSTM signaling axis similarly impairs mitotic progression and chromosome segregation by affecting orientation of the mitotic spindle and assembly of mitotic-specific actin structures. Our findings establish a unique role for HSPB8 in a novel function of BAG3 in mitotic cell division and genome stability, through effect on remodeling of the actin cytoskeleton.
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Affiliation(s)
- Margit Fuchs
- Centre de Recherche sur le Cancer de l’Université Laval and Département de Biologie Moléculaire, Biochimie Médicale et Pathologie, Université Laval, Quebec, Canada
- Oncology, Centre de Recherche du CHU de Québec-Université Laval, Quebec, Canada
| | - Carole Luthold
- Centre de Recherche sur le Cancer de l’Université Laval and Département de Biologie Moléculaire, Biochimie Médicale et Pathologie, Université Laval, Quebec, Canada
- Oncology, Centre de Recherche du CHU de Québec-Université Laval, Quebec, Canada
| | - Solenn M. Guilbert
- Centre de Recherche sur le Cancer de l’Université Laval and Département de Biologie Moléculaire, Biochimie Médicale et Pathologie, Université Laval, Quebec, Canada
- Oncology, Centre de Recherche du CHU de Québec-Université Laval, Quebec, Canada
| | - Alice Anaïs Varlet
- Centre de Recherche sur le Cancer de l’Université Laval and Département de Biologie Moléculaire, Biochimie Médicale et Pathologie, Université Laval, Quebec, Canada
- Oncology, Centre de Recherche du CHU de Québec-Université Laval, Quebec, Canada
| | - Herman Lambert
- Centre de Recherche sur le Cancer de l’Université Laval and Département de Biologie Moléculaire, Biochimie Médicale et Pathologie, Université Laval, Quebec, Canada
- Oncology, Centre de Recherche du CHU de Québec-Université Laval, Quebec, Canada
| | - Alexandra Jetté
- Centre de Recherche sur le Cancer de l’Université Laval and Département de Biologie Moléculaire, Biochimie Médicale et Pathologie, Université Laval, Quebec, Canada
- Oncology, Centre de Recherche du CHU de Québec-Université Laval, Quebec, Canada
| | - Sabine Elowe
- Reproduction, Perinatal Health and Child Health, Centre de Recherche du CHU de Québec-Université Laval, Quebec, Canada
- Centre de Recherche sur le Cancer de l’Université Laval and Département de Pédiatrie, Université Laval, Quebec, Canada
| | - Jacques Landry
- Centre de Recherche sur le Cancer de l’Université Laval and Département de Biologie Moléculaire, Biochimie Médicale et Pathologie, Université Laval, Quebec, Canada
- Oncology, Centre de Recherche du CHU de Québec-Université Laval, Quebec, Canada
| | - Josée N. Lavoie
- Centre de Recherche sur le Cancer de l’Université Laval and Département de Biologie Moléculaire, Biochimie Médicale et Pathologie, Université Laval, Quebec, Canada
- Oncology, Centre de Recherche du CHU de Québec-Université Laval, Quebec, Canada
- * E-mail:
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Abstract
The Fanconi anemia (FA) proteins are involved in a signaling network that assures the safeguard of chromosomes. To understand the function of FA proteins in cellular division events, we investigated the interaction between Stathmin-1 (STMN1) and the FA group C (FANCC) protein. STMN1 is a ubiquitous cytosolic protein that regulates microtubule dynamics. STMN1 activities are regulated through phosphorylation-dephosphorylation mechanisms that control assembly of the mitotic spindle, and dysregulation of STMN1 phosphorylation is associated with mitotic aberrancies leading to chromosome instability and cancer progression. Using different biochemical approaches, we showed that FANCC interacts and co-localizes with STMN1 at centrosomes during mitosis. We also showed that FANCC is required for STMN1 phosphorylation, as mutations in FANCC reduced serine 16- and 38-phosphorylated forms of STMN1. Phosphorylation of STMN1 at serine 16 is likely an event dependent on a functional FA pathway, as it is reduced in FANCA- and FANCD2-mutant cells. Furthermore, FA-mutant cells exhibited mitotic spindle anomalies such as supernumerary centrosomes and shorter mitotic spindles. These results suggest that FA proteins participate in the regulation of cellular division via the microtubule-associated protein STMN1.
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Affiliation(s)
- Audrey Magron
- CHU de Québec, CHUL Research Center, Québec, QC, Canada
| | - Sabine Elowe
- Department of Pediatrics, Université Laval, Québec, QC, Canada
- CHU de Québec, CHUL Research Center, Québec, QC, Canada
| | - Madeleine Carreau
- Department of Pediatrics, Université Laval, Québec, QC, Canada
- CHU de Québec, CHUL Research Center, Québec, QC, Canada
- * E-mail:
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21
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Asghar A, Lajeunesse A, Dulla K, Combes G, Thebault P, Nigg EA, Elowe S. Bub1 autophosphorylation feeds back to regulate kinetochore docking and promote localized substrate phosphorylation. Nat Commun 2015; 6:8364. [PMID: 26399325 PMCID: PMC4598568 DOI: 10.1038/ncomms9364] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Accepted: 08/13/2015] [Indexed: 12/15/2022] Open
Abstract
During mitosis, Bub1 kinase phosphorylates histone H2A-T120 to promote centromere sister chromatid cohesion through recruitment of shugoshin (Sgo) proteins. The regulation and dynamics of H2A-T120 phosphorylation are poorly understood. Using quantitative phosphoproteomics we show that Bub1 is autophosphorylated at numerous sites. We confirm mitosis-specific autophosphorylation of a several residues and show that Bub1 activation is primed in interphase but fully achieved only in mitosis. Mutation of a single autophosphorylation site T589 alters kinetochore turnover of Bub1 and results in uniform H2A-T120 phosphorylation and Sgo recruitment along chromosome arms. Consequently, improper sister chromatid resolution and chromosome segregation errors are observed. Kinetochore tethering of Bub1-T589A refocuses H2A-T120 phosphorylation and Sgo1 to centromeres. Recruitment of the Bub1-Bub3-BubR1 axis to kinetochores has recently been extensively studied. Our data provide novel insight into the regulation and kinetochore residency of Bub1 and indicate that its localization is dynamic and tightly controlled through feedback autophosphorylation.
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Affiliation(s)
- Adeel Asghar
- Faculty of Medicine, Department of Molecular and Cellular Biology, Université Laval, Québec, Canada G1V 0A6.,Department of Reproduction, Mother and Youth Health, Centre de recherche du Centre Hospitalier Universitaire de Québec, Québec, Canada G1V 4G2
| | - Audrey Lajeunesse
- Faculty of Medicine, Department of Molecular and Cellular Biology, Université Laval, Québec, Canada G1V 0A6
| | - Kalyan Dulla
- ProQR Therapeutics N.V., Darwinweg 24, Leiden 2333 CR, The Netherlands
| | - Guillaume Combes
- Faculty of Medicine, Department of Molecular and Cellular Biology, Université Laval, Québec, Canada G1V 0A6.,Department of Reproduction, Mother and Youth Health, Centre de recherche du Centre Hospitalier Universitaire de Québec, Québec, Canada G1V 4G2
| | - Philippe Thebault
- Department of Reproduction, Mother and Youth Health, Centre de recherche du Centre Hospitalier Universitaire de Québec, Québec, Canada G1V 4G2
| | - Erich A Nigg
- Biozentrum, University of Basel, Klingelbergstrasse 50/70, Basel CH-4056, Switzerland
| | - Sabine Elowe
- Faculty of Medicine, Department of Molecular and Cellular Biology, Université Laval, Québec, Canada G1V 0A6.,Department of Reproduction, Mother and Youth Health, Centre de recherche du Centre Hospitalier Universitaire de Québec, Québec, Canada G1V 4G2
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22
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Magron A, Huard C, Elowe S, Carreau M. The fanconi anemia c protein regulates cellular division via the microtubule-associated protein stathmin-1. Exp Hematol 2014. [DOI: 10.1016/j.exphem.2014.07.174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abstract
Knl1 (also known as CASC5, UniProt Q8NG31) is an evolutionarily conserved scaffolding protein that is required for proper kinetochore assembly, spindle assembly checkpoint (SAC) function and chromosome congression. A number of recent reports have confirmed the prominence of Knl1 in these processes and provided molecular details and structural features that dictate Knl1 functions in higher organisms. Knl1 recruits SAC components to the kinetochore and is the substrate of certain protein kinases and phosphatases, the interplay of which ensures the exquisite regulation of the aforementioned processes. In this Commentary, we discuss the overall domain organization of Knl1 and the roles of this protein as a versatile docking platform. We present emerging roles of the protein interaction motifs present in Knl1, including the RVSF, SILK, MELT and KI motifs, and their role in the recruitment and regulation of the SAC proteins Bub1, BubR1, Bub3 and Aurora B. Finally, we explore how the regions of low structural complexity that characterize Knl1 are implicated in the cooperative interactions that mediate binding partner recognition and scaffolding activity by Knl1.
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Affiliation(s)
- Priyanka Ghongane
- Faculty of Health and Life Sciences, Department of Biological and Medical Sciences, Oxford Brookes University, Oxford OX3 0BP, UK
| | - Maria Kapanidou
- Faculty of Health and Life Sciences, Department of Biological and Medical Sciences, Oxford Brookes University, Oxford OX3 0BP, UK
| | - Adeel Asghar
- Reproduction, Perinatal Health and Child Health, Centre de Recherche du CHUQ, 2705, Boulevard Laurier, T3-51, Québec, QC G1V 4G2, Canada
| | - Sabine Elowe
- Reproduction, Perinatal Health and Child Health, Centre de Recherche du CHUQ, 2705, Boulevard Laurier, T3-51, Québec, QC G1V 4G2, Canada
| | - Victor M Bolanos-Garcia
- Faculty of Health and Life Sciences, Department of Biological and Medical Sciences, Oxford Brookes University, Oxford OX3 0BP, UK
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Kasahara K, Goto H, Izawa I, Kiyono T, Watanabe N, Elowe S, Nigg EA, Inagaki M. PI 3-kinase-dependent phosphorylation of Plk1-Ser99 promotes association with 14-3-3γ and is required for metaphase-anaphase transition. Nat Commun 2013; 4:1882. [PMID: 23695676 PMCID: PMC3675326 DOI: 10.1038/ncomms2879] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Accepted: 04/11/2013] [Indexed: 12/31/2022] Open
Abstract
Polo-like kinase 1 (Plk1) controls multiple aspects of mitosis and is activated through its phosphorylation at Thr210. Here we identify Ser99 on Plk1 as a novel mitosis-specific phosphorylation site, which operates independently of Plk1-Thr210 phosphorylation. Plk1-Ser99 phosphorylation creates a docking site for 14-3-3γ, and this interaction stimulates the catalytic activity of Plk1. Knockdown of 14-3-3γ or replacement of wild-type (WT) Plk1 by a Ser99-phospho-blocking mutant leads to a prometaphase/metaphase-like arrest due to the activation of the spindle assembly checkpoint. Inhibition of phosphatidylinositol 3-kinase (PI3K) and Akt significantly reduces the level of Plk1-Ser99 phosphorylation and delays metaphase to anaphase transition. Plk1-Ser99 phosphorylation requires not only Akt activity but also protein(s) associated with Plk1 in a mitosis-specific manner. Therefore, mitotic Plk1 activity is regulated not only by Plk1-Thr210 phosphorylation, but also by Plk1 binding to 14-3-3γ following Plk1-Ser99 phosphorylation downstream of the PI3K-Akt signalling pathway. This novel Plk1 activation pathway controls proper progression from metaphase to anaphase.
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Affiliation(s)
- Kousuke Kasahara
- Division of Biochemistry, Aichi Cancer Center Research Institute, Nagoya, Aichi 464-8681, Japan
- Department of Oncology, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Aichi 467-8603, Japan
| | - Hidemasa Goto
- Division of Biochemistry, Aichi Cancer Center Research Institute, Nagoya, Aichi 464-8681, Japan
- Department of Cellular Oncology, Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550, Japan
| | - Ichiro Izawa
- Division of Biochemistry, Aichi Cancer Center Research Institute, Nagoya, Aichi 464-8681, Japan
| | - Tohru Kiyono
- Division of Virology, National Cancer Center Research Institute, Chuo-ku, Tokyo 104-0045, Japan
| | - Nobumoto Watanabe
- Chemical Library Validation Team, Chemical Biology Department, RIKEN Advanced Science Institute (ASI), 2-1, Hirosawa, Wako, Saitama 351-0198, Japan
| | - Sabine Elowe
- Centre de Recherche du CHUQ, 2705 Boulevard Laurier, RC-9800, Quebec City, Québec, Canada G1V 4G2
- Département de Pédiatrie, Faculté de Médicine, Université Laval, 2705 Boulevard Laurier, Quebec City, Québec, Canada G1V 4G2
| | - Erich A Nigg
- Biozentrum, University of Basel, Klingelbergstrasse 50/70, CH-4056 Basel, Switzerland
| | - Masaki Inagaki
- Division of Biochemistry, Aichi Cancer Center Research Institute, Nagoya, Aichi 464-8681, Japan
- Department of Cellular Oncology, Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550, Japan
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25
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Lee S, Thebault P, Freschi L, Beaufils S, Blundell TL, Landry CR, Bolanos-Garcia VM, Elowe S. Characterization of spindle checkpoint kinase Mps1 reveals domain with functional and structural similarities to tetratricopeptide repeat motifs of Bub1 and BubR1 checkpoint kinases. J Biol Chem 2011; 287:5988-6001. [PMID: 22187426 PMCID: PMC3285366 DOI: 10.1074/jbc.m111.307355] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Kinetochore targeting of the mitotic kinases Bub1, BubR1, and Mps1 has been implicated in efficient execution of their functions in the spindle checkpoint, the self-monitoring system of the eukaryotic cell cycle that ensures chromosome segregation occurs with high fidelity. In all three kinases, kinetochore docking is mediated by the N-terminal region of the protein. Deletions within this region result in checkpoint failure and chromosome segregation defects. Here, we use an interdisciplinary approach that includes biophysical, biochemical, cell biological, and bioinformatics methods to study the N-terminal region of human Mps1. We report the identification of a tandem repeat of the tetratricopeptide repeat (TPR) motif in the N-terminal kinetochore binding region of Mps1, with close homology to the tandem TPR motif of Bub1 and BubR1. Phylogenetic analysis indicates that TPR Mps1 was acquired after the split between deutorostomes and protostomes, as it is distinguishable in chordates and echinoderms. Overexpression of TPR Mps1 resulted in decreased efficiency of both chromosome alignment and mitotic arrest, likely through displacement of endogenous Mps1 from the kinetochore and decreased Mps1 catalytic activity. Taken together, our multidisciplinary strategy provides new insights into the evolution, structural organization, and function of Mps1 N-terminal region.
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Affiliation(s)
- Semin Lee
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, United Kingdom
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26
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Dou Z, von Schubert C, Körner R, Santamaria A, Elowe S, Nigg EA. Quantitative mass spectrometry analysis reveals similar substrate consensus motif for human Mps1 kinase and Plk1. PLoS One 2011; 6:e18793. [PMID: 21533207 PMCID: PMC3076450 DOI: 10.1371/journal.pone.0018793] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2010] [Accepted: 03/18/2011] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Members of the Mps1 kinase family play an essential and evolutionarily conserved role in the spindle assembly checkpoint (SAC), a surveillance mechanism that ensures accurate chromosome segregation during mitosis. Human Mps1 (hMps1) is highly phosphorylated during mitosis and many phosphorylation sites have been identified. However, the upstream kinases responsible for these phosphorylations are not presently known. METHODOLOGY/PRINCIPAL FINDINGS Here, we identify 29 in vivo phosphorylation sites in hMps1. While in vivo analyses indicate that Aurora B and hMps1 activity are required for mitotic hyper-phosphorylation of hMps1, in vitro kinase assays show that Cdk1, MAPK, Plk1 and hMps1 itself can directly phosphorylate hMps1. Although Aurora B poorly phosphorylates hMps1 in vitro, it positively regulates the localization of Mps1 to kinetochores in vivo. Most importantly, quantitative mass spectrometry analysis demonstrates that at least 12 sites within hMps1 can be attributed to autophosphorylation. Remarkably, these hMps1 autophosphorylation sites closely resemble the consensus motif of Plk1, demonstrating that these two mitotic kinases share a similar substrate consensus. CONCLUSIONS/SIGNIFICANCE hMps1 kinase is regulated by Aurora B kinase and its autophosphorylation. Analysis on hMps1 autophosphorylation sites demonstrates that hMps1 has a substrate preference similar to Plk1 kinase.
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Affiliation(s)
- Zhen Dou
- Department of Cell Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
- Hefei National Laboratory of Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, China
| | | | - Roman Körner
- Department of Cell Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Anna Santamaria
- Department of Cell Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
- Biozentrum, University of Basel, Basel, Switzerland
| | - Sabine Elowe
- Department of Cell Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Erich A. Nigg
- Department of Cell Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
- Biozentrum, University of Basel, Basel, Switzerland
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27
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Santamaria A, Wang B, Elowe S, Malik R, Zhang F, Bauer M, Schmidt A, Silljé HHW, Körner R, Nigg EA. The Plk1-dependent phosphoproteome of the early mitotic spindle. Mol Cell Proteomics 2011; 10:M110.004457. [PMID: 20860994 PMCID: PMC3013462 DOI: 10.1074/mcp.m110.004457] [Citation(s) in RCA: 182] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2010] [Indexed: 12/31/2022] Open
Abstract
Polo-like kinases regulate many aspects of mitotic and meiotic progression from yeast to man. In early mitosis, mammalian Polo-like kinase 1 (Plk1) controls centrosome maturation, spindle assembly, and microtubule attachment to kinetochores. However, despite the essential and diverse functions of Plk1, the full range of Plk1 substrates remains to be explored. To investigate the Plk1-dependent phosphoproteome of the human mitotic spindle, we combined stable isotope labeling by amino acids in cell culture with Plk1 inactivation or depletion followed by spindle isolation and mass spectrometry. Our study identified 358 unique Plk1-dependent phosphorylation sites on spindle proteins, including novel substrates, illustrating the complexity of the Plk1-dependent signaling network. Over 100 sites were validated by in vitro phosphorylation of peptide arrays, resulting in a broadening of the Plk1 consensus motif. Collectively, our data provide a rich source of information on Plk1-dependent phosphorylation, Plk1 docking to substrates, the influence of phosphorylation on protein localization, and the functional interaction between Plk1 and Aurora A on the early mitotic spindle.
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Affiliation(s)
- Anna Santamaria
- Department of Cell Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany.
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28
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Elowe S, Dulla K, Uldschmid A, Li X, Dou Z, Nigg EA. Uncoupling of the spindle-checkpoint and chromosome-congression functions of BubR1. J Cell Sci 2010; 123:84-94. [PMID: 20016069 DOI: 10.1242/jcs.056507] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The BubR1 checkpoint protein performs multiple functions in mitosis. We have carried out a functional analysis of conserved motifs of human BubR1 (also known as BUB1B) and demonstrate that spindle assembly checkpoint (SAC) and chromosome attachment functions can be uncoupled from each other. Mutation of five proline-directed serine phosphorylation sites, identified in vivo by mass spectrometry, essentially abolishes attachment of chromosomes to the spindle but has no effect on SAC functionality. By contrast, mutation of the two conserved KEN boxes required for SAC function does not impact chromosome congression. Interestingly, the contribution of the two KEN-box motifs is not equal. Cdc20 associates with the N-terminal but not C-terminal KEN box, and mutation of the N-terminal KEN motif results in more severe acceleration of mitotic timing. Moreover, the two KEN motifs are not sufficient for maximal binding of Cdc20 and APC/C, which also requires sequences in the BubR1 C-terminus. Finally, mutation of the GLEBS motif causes loss of Bub3 interaction and mislocalization of BubR1 from the kinetochore; concomitantly, BubR1 phosphorylation as well as SAC activity and chromosome congression are impaired, indicating that the GLEBS motif is strictly required for both major functions of human BubR1.
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Affiliation(s)
- Sabine Elowe
- Department of Cell Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany.
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29
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Elowe S, Hümmer S, Uldschmid A, Li X, Nigg EA. Tension-sensitive Plk1 phosphorylation on BubR1 regulates the stability of kinetochore microtubule interactions. Genes Dev 2007; 21:2205-19. [PMID: 17785528 PMCID: PMC1950859 DOI: 10.1101/gad.436007] [Citation(s) in RCA: 239] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2007] [Accepted: 07/19/2007] [Indexed: 11/25/2022]
Abstract
Mitotic phosphorylation of the spindle checkpoint component BubR1 is highly conserved throughout evolution. Here, we demonstrate that BubR1 is phosphorylated on the Cdk1 site T620, which triggers the recruitment of Plk1 and phosphorylation of BubR1 by Plk1 both in vitro and in vivo. Phosphorylation does not appear to be required for spindle checkpoint function but instead is important for the stability of kinetochore-microtubule (KT-MT) interactions, timely mitotic progression, and chromosome alignment onto the metaphase plate. By quantitative mass spectrometry, we identify S676 as a Plk1-specific phosphorylation site on BubR1. Furthermore, using a phospho-specific antibody, we show that this site is phosphorylated during prometaphase, but dephosphorylated at metaphase upon establishment of tension between sister chromatids. These findings describe the first in vivo verified phosphorylation site for human BubR1, identify Plk1 as the kinase responsible for causing the characteristic mitotic BubR1 upshift, and attribute a KT-specific function to the hyperphosphorylated form of BubR1 in the stabilization of KT-MT interactions.
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Affiliation(s)
- Sabine Elowe
- Department of Cell Biology, Max Planck Institute of Biochemistry, D-82152 Martinsried, Germany
| | - Stefan Hümmer
- Department of Cell Biology, Max Planck Institute of Biochemistry, D-82152 Martinsried, Germany
| | - Andreas Uldschmid
- Department of Cell Biology, Max Planck Institute of Biochemistry, D-82152 Martinsried, Germany
| | - Xiuling Li
- Department of Cell Biology, Max Planck Institute of Biochemistry, D-82152 Martinsried, Germany
| | - Erich A. Nigg
- Department of Cell Biology, Max Planck Institute of Biochemistry, D-82152 Martinsried, Germany
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30
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Alford SC, Bazowski J, Lorimer H, Elowe S, Howard PL. Tissue transglutaminase clusters soluble A-type ephrins into functionally active high molecular weight oligomers. Exp Cell Res 2007; 313:4170-9. [PMID: 17707797 DOI: 10.1016/j.yexcr.2007.07.019] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2007] [Revised: 07/17/2007] [Accepted: 07/19/2007] [Indexed: 11/20/2022]
Abstract
The Eph receptors and their ligands, the ephrins, are thought to act at points of close cell-cell contact to elicit bi-directional signaling in receptor and ligand expressing cells. However, when cultured in vitro, some A-type ephrins are released from the cell surface and it is unclear if these soluble ephrins participate in Eph receptor activation. We show that soluble ephrin A5 is subject to oligomerization. Ephrins A1 and A5 are substrates for a cross-linking enzyme, tissue transglutaminase, which mediates the formation of oligomeric ephrin. Transglutaminase-cross-linked ephrin binds to A-type Eph receptors, stimulates Eph kinase activity, and promotes invasion and migration of HeLa cells. Transglutaminase-mediated oligomerization of soluble ephrin potentially represents a novel mechanism of forward signaling through Eph receptors and may extend the influence of A-type ephrins beyond cell contact mediated signaling.
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Affiliation(s)
- Spencer C Alford
- Centre for Biomedical Research, University of Victoria, PO Box 3020 Station CSC Victoria, BC, Canada V8W 3N5
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Huusko P, Ponciano-Jackson D, Wolf M, Kiefer JA, Azorsa DO, Tuzmen S, Weaver D, Robbins C, Moses T, Allinen M, Hautaniemi S, Chen Y, Elkahloun A, Basik M, Bova GS, Bubendorf L, Lugli A, Sauter G, Schleutker J, Ozcelik H, Elowe S, Pawson T, Trent JM, Carpten JD, Kallioniemi OP, Mousses S. Nonsense-mediated decay microarray analysis identifies mutations of EPHB2 in human prostate cancer. Nat Genet 2004; 36:979-83. [PMID: 15300251 DOI: 10.1038/ng1408] [Citation(s) in RCA: 152] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2004] [Accepted: 06/22/2004] [Indexed: 11/09/2022]
Abstract
The identification of tumor-suppressor genes in solid tumors by classical cancer genetics methods is difficult and slow. We combined nonsense-mediated RNA decay microarrays and array-based comparative genomic hybridization for the genome-wide identification of genes with biallelic inactivation involving nonsense mutations and loss of the wild-type allele. This approach enabled us to identify previously unknown mutations in the receptor tyrosine kinase gene EPHB2. The DU 145 prostate cancer cell line, originating from a brain metastasis, carries a truncating mutation of EPHB2 and a deletion of the remaining allele. Additional frameshift, splice site, missense and nonsense mutations are present in clinical prostate cancer samples. Transfection of DU 145 cells, which lack functional EphB2, with wild-type EPHB2 suppresses clonogenic growth. Taken together with studies indicating that EphB2 may have an essential role in cell migration and maintenance of normal tissue architecture, our findings suggest that mutational inactivation of EPHB2 may be important in the progression and metastasis of prostate cancer.
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Affiliation(s)
- Pia Huusko
- Translational Genomics Research Institute, Cancer Drug Development Laboratory, 20 Firstfield Road, Suite 110, Gaithersburg, Maryland 20878, USA
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Tong J, Elowe S, Nash P, Pawson T. Manipulation of EphB2 regulatory motifs and SH2 binding sites switches MAPK signaling and biological activity. J Biol Chem 2003; 278:6111-9. [PMID: 12486127 DOI: 10.1074/jbc.m208972200] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Signaling by the Eph family of receptor tyrosine kinases (RTKs) is complex, because they can interact with a variety of intracellular targets, and can potentially induce distinct responses in different cell types. In NG108 neuronal cells, activated EphB2 recruits p120RasGAP, in a fashion that is associated with down-regulation of the Ras-Erk mitogen-activated kinase (MAPK) pathway and neurite retraction. To pursue the role of the Ras-MAPK pathway in EphB2-mediated growth cone collapse, and to explore the biochemical and biological functions of Eph receptors, we sought to re-engineer the signaling properties of EphB2 by manipulating its regulatory motifs and SH2 binding sites. An EphB2 mutant that retained juxtamembrane (JM) RasGAP binding sites but incorporated a Grb2 binding motif at an alternate RasGAP binding site within the kinase domain had little effect on basal Erk MAPK activation. In contrast, elimination of all RasGAP binding sites, accompanied by the addition of a Grb2 binding site within the kinase domain, led to an increase in phospho-Erk levels in NG108 cells following ephrin-B1 stimulation. Functional assays indicated a correlation between neurite retraction and the ability of the EphB2 mutants to down-regulate Ras-Erk MAPK signaling. These data suggest that EphB2 can be designed to repress, stabilize, or activate the Ras-Erk MAPK pathway by the manipulation of RasGAP and Grb2 SH2 domain binding sites and support the notion that Erk MAPK regulation plays a significant role in axon guidance. The behavior of EphB2 variants with mutations in the JM region and kinase domains suggests an intricate pattern of regulation and target recognition by Eph receptors.
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Affiliation(s)
- Jiefei Tong
- Programe in Molecular Biology and Cancer, Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario M5G 1X5
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Abstract
Members of the Eph family of receptor tyrosine kinases control many aspects of cellular interactions during development, including axon guidance. Here, we demonstrate that EphB2 also regulates postnatal synaptic function in the mammalian CNS. Mice lacking the EphB2 intracellular kinase domain showed wild-type levels of LTP, whereas mice lacking the entire EphB2 receptor had reduced LTP at hippocampal CA1 and dentate gyrus synapses. Synaptic NMDA-mediated current was reduced in dentate granule neurons in EphB2 null mice, as was synaptically localized NR1 as revealed by immunogold localization. Finally, we show that EphB2 is upregulated in hippocampal pyramidal neurons in vitro and in vivo by stimuli known to induce changes in synaptic structure. Together, these data demonstrate that EphB2 plays an important role in regulating synaptic function.
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Affiliation(s)
- J T Henderson
- Program in Molecular Biology and Cancer, Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Avenue, M5G 1X5, Toronto, Ontario, Canada.
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Elowe S, Holland SJ, Kulkarni S, Pawson T. Downregulation of the Ras-mitogen-activated protein kinase pathway by the EphB2 receptor tyrosine kinase is required for ephrin-induced neurite retraction. Mol Cell Biol 2001; 21:7429-41. [PMID: 11585923 PMCID: PMC99915 DOI: 10.1128/mcb.21.21.7429-7441.2001] [Citation(s) in RCA: 150] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Activation of the EphB2 receptor tyrosine kinase by clustered ephrin-B1 induces growth cone collapse and neurite retraction in differentiated NG108 neuronal cells. We have investigated the cytoplasmic signaling events associated with EphB2-induced cytoskeletal reorganization in these neuronal cells. We find that unlike other receptor tyrosine kinases, EphB2 induces a pronounced downregulation of GTP-bound Ras and consequently of the extracellular signal-regulated kinase (ERK) mitogen-activated protein kinase (MAPK) pathway. A similar inhibition of the Ras-MAPK pathway was observed on stimulation of endogenous EphB2 in COS-1 cells. Inactivation of Ras, induced by ephrin B1 stimulation of NG108 neuronal cells, requires EphB2 tyrosine kinase activity and is blocked by a truncated form of p120-Ras GTPase-activating protein (p120-RasGAP), suggesting that EphB2 signals through the SH2 domain protein p120-RasGAP to inhibit the Ras-MAPK pathway. Suppression of Ras activity appears functionally important, since expression of a constitutively active variant of Ras impaired the ability of EphB2 to induce neurite retraction. In addition, EphB2 attenuated the elevation in ERK activation induced by attachment of NG108 cells to fibronectin, indicating that the EphB2 receptor can modulate integrin signaling to the Ras GTPase. These results suggest that a primary function of EphB2, a member of the most populous family of receptor tyrosine kinases, is to inactivate the Ras-MAPK pathway in a fashion that contributes to cytoskeletal reorganization and adhesion responses in neuronal growth cones.
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Affiliation(s)
- S Elowe
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario M5G 1X5, Canada
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Abstract
UDP-GlcNAc: Manalpha1-6Manbeta-R beta1-6 N-acetylglucosaminyltransferase V (EC 2.4.1.155, GlcNAc-TV) is a Golgi enzyme that substitutes the trimannosyl core in the biosynthetic pathway for complex-type N-linked glycans. GlcNAc-TV activity is regulated by oncogenes frequently activated in cancer cells ( ras, src, and her2/neu ) and by activators of T lymphocytes. Overexpression of GlcNAc-TV in epithelial cells results in morphological transformation, while tumor cell mutants selected for loss of GlcNAc-TV products show diminished malignant potential in mice. In this report, we have expressed and characterized a series of N- and C-terminal deletions of GlcNAc-TV. Portions of GlcNAc-TV sequence were fused at the N-terminal domain to IgG-binding domains of staphylococcal Protein A and expressed in CHOP cells. The secreted fusion proteins were purified by IgG Sepharose affinity chromatography and assayed for enzyme activities. The peptide sequence S(213-740)of GlcNAc-TV was determined to be essential for the catalytic activity, the remaining amino acids comprising a 183 amino acid stem region, a 17 amino acid transmembrane domain and a 12 amino acid cytosolic moiety. Further deletion of 5 amino acids to produce peptide R(218-740)reduced enzyme activity by 20-fold. Similar K(m)and V(max)values for donor and acceptor were observed for peptide S(213-740), the minimal catalytic domain, and peptide Q(39-740), which also included the stem region. Truncation of five amino acids from the C-terminus also resulted in a 20-fold loss of catalytic activity. Secondary structure predictions suggest a high frequency of turns in the stem region, and more contiguous stretches of alpha-helix found in the catalytic domain.
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Affiliation(s)
- B Korczak
- GlycoDesign Inc., Toronto, Ontario, Canada
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