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Wei X, Fang X, Yu X, Li H, Guo Y, Qi Y, Sun C, Han D, Liu X, Li N, Hu H. Integrative analysis of single-cell embryo data reveals transcriptome signatures for the human pre-implantation inner cell mass. Dev Biol 2023; 502:39-49. [PMID: 37437860 DOI: 10.1016/j.ydbio.2023.07.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 07/05/2023] [Accepted: 07/09/2023] [Indexed: 07/14/2023]
Abstract
As the source of embryonic stem cells (ESCs), inner cell mass (ICM) can form all tissues of the embryo proper, however, its role in early human lineage specification remains controversial. Although a stepwise differentiation model has been proposed suggesting the existence of ICM as a distinct developmental stage, the underlying molecular mechanism remains unclear. In the present study, we perform an integrated analysis on the public human preimplantation embryonic single-cell transcriptomic data and apply a trajectory inference algorithm to measure the cell plasticity. In our results, ICM population can be clearly discriminated on the dimension-reduced graph and confirmed by compelling evidences, thus validating the two-step hypothesis of lineage commitment. According to the branch probabilities and differentiation potential, we determine the precise time points for two lineage segregations. Further analysis on gene expression dynamics and regulatory network indicates that transcription factors including GSC, PRDM1, and SPIC may underlie the decisions of ICM fate. In addition, new human ICM marker genes, such as EPHA4 and CCR8 are discovered and validated by immunofluorescence. Given the potential clinical applications of ESCs, our analysis provides a further understanding of human ICM cells and facilitates the exploration of more unique characteristics in early human development.
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Affiliation(s)
- Xinshu Wei
- School of Medicine, South China University of Technology, Guangzhou, China; Laboratory of Medical Systems Biology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, 510623, China
| | - Xiang Fang
- Medical Research Institute, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, China
| | - Xiu Yu
- School of Medicine, Jiaying University, Meizhou, 514015, China; Department of Histology and Embryology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China; Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Sun Yat-sen University, Guangzhou, 510080, China
| | - Hong Li
- Laboratory of Medical Systems Biology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, 510623, China
| | - Yuyang Guo
- Laboratory of Medical Systems Biology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, 510623, China
| | - Yifei Qi
- Laboratory of Medical Systems Biology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, 510623, China
| | - Chuanbo Sun
- Laboratory of Medical Systems Biology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, 510623, China
| | - Dingding Han
- Department of Clinical Laboratory, Shanghai Children's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200062, China
| | - Xiaonan Liu
- Department of Assisted Reproductive Technology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, 510623, China
| | - Na Li
- Laboratory of Medical Systems Biology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, 510623, China.
| | - Hao Hu
- Laboratory of Medical Systems Biology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, Guangzhou, 510623, China; Provincial Key Laboratory of Research in Structure Birth Defect Disease and Department of Pediatric Surgery, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510623, China; Third Affiliatied Hospital of Zhengzhou University, Zhengzhou, China.
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2
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Ng XW, Chung YH, Asadi F, Kong C, Ustione A, Piston DW. RhoA as a Signaling Hub Controlling Glucagon Secretion From Pancreatic α-Cells. Diabetes 2022; 71:2384-2394. [PMID: 35904939 PMCID: PMC9630081 DOI: 10.2337/db21-1010] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 07/26/2022] [Indexed: 11/13/2022]
Abstract
Glucagon hypersecretion from pancreatic islet α-cells exacerbates hyperglycemia in type 1 diabetes (T1D) and type 2 diabetes. Still, the underlying mechanistic pathways that regulate glucagon secretion remain controversial. Among the three complementary main mechanisms (intrinsic, paracrine, and juxtacrine) proposed to regulate glucagon release from α-cells, juxtacrine interactions are the least studied. It is known that tonic stimulation of α-cell EphA receptors by ephrin-A ligands (EphA forward signaling) inhibits glucagon secretion in mouse and human islets and restores glucose inhibition of glucagon secretion in sorted mouse α-cells, and these effects correlate with increased F-actin density. Here, we elucidate the downstream target of EphA signaling in α-cells. We demonstrate that RhoA, a Rho family GTPase, plays a key role in this pathway. Pharmacological inhibition of RhoA disrupts glucose inhibition of glucagon secretion in islets and decreases cortical F-actin density in dispersed α-cells and α-cells in intact islets. Quantitative FRET biosensor imaging shows that increased RhoA activity follows directly from EphA stimulation. We show that in addition to modulating F-actin density, EphA forward signaling and RhoA activity affect α-cell Ca2+ activity in a novel mechanistic pathway. Finally, we show that stimulating EphA forward signaling restores glucose inhibition of glucagon secretion from human T1D donor islets.
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Affiliation(s)
| | | | | | | | | | - David W. Piston
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO
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3
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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: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [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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4
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Abstract
The EPH receptor tyrosine kinases and their signaling partners, the EPHRINS, comprise a large class of cell signaling molecules that plays diverse roles in development. As cell membrane-anchored signaling molecules, they regulate cellular organization by modulating the strength of cellular contacts, usually by impacting the actin cytoskeleton or cell adhesion programs. Through these cellular functions, EPH/EPHRIN signaling often regulates tissue shape. Indeed, recent evidence indicates that this signaling family is ancient and associated with the origin of multicellularity. Though extensively studied, our understanding of the signaling mechanisms employed by this large family of signaling proteins remains patchwork, and a truly "canonical" EPH/EPHRIN signal transduction pathway is not known and may not exist. Instead, several foundational evolutionarily conserved mechanisms are overlaid by a myriad of tissue -specific functions, though common themes emerge from these as well. Here, I review recent advances and the related contexts that have provided new understanding of the conserved and varied molecular and cellular mechanisms employed by EPH/EPHRIN signaling during development.
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Affiliation(s)
- Jeffrey O Bush
- Department of Cell and Tissue Biology, University of California San Francisco, San Francisco, CA, United States; Program in Craniofacial Biology, University of California San Francisco, San Francisco, CA, United States; Institute for Human Genetics, University of California San Francisco, San Francisco, CA, United States; Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California San Francisco, San Francisco, CA, United States.
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5
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de Araujo LS, Ribeiro-Alves M, Wipperman MF, Vorkas CK, Pessler F, Saad MHF. Transcriptomic Biomarkers for Tuberculosis: Validation of NPC2 as a Single mRNA Biomarker to Diagnose TB, Predict Disease Progression, and Monitor Treatment Response. Cells 2021; 10:cells10102704. [PMID: 34685683 PMCID: PMC8534371 DOI: 10.3390/cells10102704] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 09/27/2021] [Accepted: 09/28/2021] [Indexed: 12/13/2022] Open
Abstract
External validation in different cohorts is a key step in the translational development of new biomarkers. We previously described three host mRNA whose expression in peripheral blood is significantly higher (NPC2) or lower (DOCK9 and EPHA4) in individuals with TB compared to latent TB infection (LTBI) and controls. We have now conducted an independent validation of these genes by re-analyzing publicly available transcriptomic datasets from Brazil, China, Haiti, India, South Africa, and the United Kingdom. Comparisons between TB and control/LTBI showed significant differential expression of all three genes (NPC2high p < 0.01, DOCK9low p < 0.01, and EPHA4low p < 0.05). NPC2high had the highest mean area under the ROC curve (AUROC) for the differentiation of TB vs. controls (0.95) and LTBI (0.94). In addition, NPC2 accurately distinguished TB from the clinically similar conditions pneumonia (AUROC, 0.88), non-active sarcoidosis (0.87), and lung cancer (0.86), but not from active sarcoidosis (0.66). Interestingly, individuals progressing from LTBI to TB showed a constant increase in NPC2 expression with time when compared to non-progressors (p < 0.05), with a significant change closer to manifestation of active disease (≤3 months, p = 0.003). Moreover, NPC2 expression normalized with completion of anti-TB treatment. Taken together, these results validate NPC2 mRNA as a diagnostic host biomarker for active TB independent of host genetic background. Moreover, they reveal its potential to predict progression from latent to active infection and to indicate a response to anti-TB treatment.
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Affiliation(s)
- Leonardo S. de Araujo
- Cellular Microbiology Laboratory, Oswaldo Cruz Institute (IOC), Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro 20045-360, Brazil;
- Research Group Biomarkers for Infectious Diseases, TWINCORE Centre for Experimental and Clinical Infection Research, 30519 Hannover, Germany
| | - Marcelo Ribeiro-Alves
- National Institute of Infectology Evandro Chagas, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro 21040-360, Brazil;
| | - Matthew F. Wipperman
- Immunology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10021, USA; (M.F.W.); (C.K.V.)
- Clinical and Translational Science Center, Weill Cornell Medicine, New York, NY 10021, USA
| | - Charles Kyriakos Vorkas
- Immunology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10021, USA; (M.F.W.); (C.K.V.)
- Division of Infectious Diseases, Renaissance School of Medicine, Stony Brook University, Stony Brook, NY 11794, USA
| | - Frank Pessler
- Research Group Biomarkers for Infectious Diseases, TWINCORE Centre for Experimental and Clinical Infection Research, 30519 Hannover, Germany
- Centre for Individualised Infection Medicine, 30625 Hannover, Germany
- Helmholtz Center for Infection Research, 38124 Braunschweig, Germany
- Correspondence: or (F.P.); or (M.H.F.S.); Tel.: +49-511-220027167 (F.P.); +55-21-25621598 (M.H.F.S.)
| | - Maria Helena Féres Saad
- Cellular Microbiology Laboratory, Oswaldo Cruz Institute (IOC), Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro 20045-360, Brazil;
- Correspondence: or (F.P.); or (M.H.F.S.); Tel.: +49-511-220027167 (F.P.); +55-21-25621598 (M.H.F.S.)
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6
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Abstract
The non-catalytic region of tyrosine kinase (Nck) family of adaptors, consisting of Nck1 and Nck2, contributes to selectivity and specificity in the flow of cellular information by recruiting components of signaling networks. Known to play key roles in cytoskeletal remodeling, Nck adaptors modulate host cell-pathogen interactions, immune cell receptor activation, cell adhesion and motility, and intercellular junctions in kidney podocytes. Genetic inactivation of both members of the Nck family results in embryonic lethality; however, viability of mice lacking either one of these adaptors suggests partial functional redundancy. In this Cell Science at a Glance and the accompanying poster, we highlight the molecular organization and functions of the Nck family, focusing on key interactions and pathways, regulation of cellular processes, development, homeostasis and pathogenesis, as well as emerging and non-redundant functions of Nck1 compared to those of Nck2. This article thus aims to provide a timely perspective on the biology of Nck adaptors and their potential as therapeutic targets.
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Affiliation(s)
- Briana C. Bywaters
- Department of Veterinary Pathobiology, Texas A&M University, College Station, TX 7783, USA
| | - Gonzalo M. Rivera
- Department of Veterinary Pathobiology, Texas A&M University, College Station, TX 7783, USA
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7
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Light TP, Gomez-Soler M, Wang Z, Karl K, Zapata-Mercado E, Gehring MP, Lechtenberg BC, Pogorelov TV, Hristova K, Pasquale EB. A cancer mutation promotes EphA4 oligomerization and signaling by altering the conformation of the SAM domain. J Biol Chem 2021; 297:100876. [PMID: 34139238 PMCID: PMC8260879 DOI: 10.1016/j.jbc.2021.100876] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Revised: 05/20/2021] [Accepted: 06/13/2021] [Indexed: 12/24/2022] Open
Abstract
The Eph receptor tyrosine kinases and their ephrin ligands regulate many physiological and pathological processes. EphA4 plays important roles in nervous system development and adult homeostasis, while aberrant EphA4 signaling has been implicated in neurodegeneration. EphA4 may also affect cancer malignancy, but the regulation and effects of EphA4 signaling in cancer are poorly understood. A correlation between decreased patient survival and high EphA4 mRNA expression in melanoma tumors that also highly express ephrinA ligands suggests that enhanced EphA4 signaling may contribute to melanoma progression. A search for EphA4 gain-of-function mutations in melanoma uncovered a mutation of the highly conserved leucine 920 in the EphA4 sterile alpha motif (SAM) domain. We found that mutation of L920 to phenylalanine (L920F) potentiates EphA4 autophosphorylation and signaling, making it the first documented EphA4 cancer mutation that increases kinase activity. Quantitative Föster resonance energy transfer and fluorescence intensity fluctuation (FIF) analyses revealed that the L920F mutation induces a switch in EphA4 oligomer size, from a dimer to a trimer. We propose this switch in oligomer size as a novel mechanism underlying EphA4-linked tumorigenesis. Molecular dynamics simulations suggest that the L920F mutation alters EphA4 SAM domain conformation, leading to the formation of EphA4 trimers that assemble through two aberrant SAM domain interfaces. Accordingly, EphA4 wild-type and the L920F mutant are affected differently by the SAM domain and are differentially regulated by ephrin ligand stimulation. The increased EphA4 activation induced by the L920F mutation, through the novel mechanism we uncovered, supports a functional role for EphA4 in promoting pathogenesis.
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Affiliation(s)
- Taylor P Light
- Department of Materials Science and Engineering, Institute for NanoBioTechnology, Johns Hopkins University, Baltimore, Maryland, USA
| | - Maricel Gomez-Soler
- Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California, USA
| | - Zichen Wang
- Department of Chemistry, Center for Biophysics and Quantitative Biology, Beckman Institute for Advanced Science and Technology, and National Center for Supercomputing Applications, School of Chemical Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - Kelly Karl
- Program in Molecular Biophysics, Institute for NanoBioTechnology, Johns Hopkins University, Baltimore, Maryland, USA
| | - Elmer Zapata-Mercado
- Program in Molecular Biophysics, Institute for NanoBioTechnology, Johns Hopkins University, Baltimore, Maryland, USA
| | - Marina P Gehring
- Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California, USA
| | - Bernhard C Lechtenberg
- Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California, USA
| | - Taras V Pogorelov
- Department of Chemistry, Center for Biophysics and Quantitative Biology, Beckman Institute for Advanced Science and Technology, and National Center for Supercomputing Applications, School of Chemical Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - Kalina Hristova
- Department of Materials Science and Engineering, Institute for NanoBioTechnology, Johns Hopkins University, Baltimore, Maryland, USA; Program in Molecular Biophysics, Institute for NanoBioTechnology, Johns Hopkins University, Baltimore, Maryland, USA.
| | - Elena B Pasquale
- Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California, USA.
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8
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Protein context shapes the specificity of SH3 domain-mediated interactions in vivo. Nat Commun 2021; 12:1597. [PMID: 33712617 PMCID: PMC7954794 DOI: 10.1038/s41467-021-21873-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 02/17/2021] [Indexed: 02/07/2023] Open
Abstract
Protein–protein interactions (PPIs) between modular binding domains and their target peptide motifs are thought to largely depend on the intrinsic binding specificities of the domains. The large family of SRC Homology 3 (SH3) domains contribute to cellular processes via their ability to support such PPIs. While the intrinsic binding specificities of SH3 domains have been studied in vitro, whether each domain is necessary and sufficient to define PPI specificity in vivo is largely unknown. Here, by combining deletion, mutation, swapping and shuffling of SH3 domains and measurements of their impact on protein interactions in yeast, we find that most SH3s do not dictate PPI specificity independently from their host protein in vivo. We show that the identity of the host protein and the position of the SH3 domains within their host are critical for PPI specificity, for cellular functions and for key biophysical processes such as phase separation. Our work demonstrates the importance of the interplay between a modular PPI domain such as SH3 and its host protein in establishing specificity to wire PPI networks. These findings will aid understanding how protein networks are rewired during evolution and in the context of mutation-driven diseases such as cancer. The SRC Homology 3 (SH3) domains mediate protein–protein interactions (PPIs). Here, the authors assess the SH3-mediated PPIs in yeast, and show that the identity of the protein itself and the position of the SH3 both affect the interaction specificity and thus the PPI-dependent cellular functions.
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9
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Arcas A, Wilkinson DG, Nieto MÁ. The Evolutionary History of Ephs and Ephrins: Toward Multicellular Organisms. Mol Biol Evol 2020; 37:379-394. [PMID: 31589243 PMCID: PMC6993872 DOI: 10.1093/molbev/msz222] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Eph receptor (Eph) and ephrin signaling regulate fundamental developmental processes through both forward and reverse signaling triggered upon cell–cell contact. In vertebrates, they are both classified into classes A and B, and some representatives have been identified in many metazoan groups, where their expression and functions have been well studied. We have extended previous phylogenetic analyses and examined the presence of Eph and ephrins in the tree of life to determine their origin and evolution. We have found that 1) premetazoan choanoflagellates may already have rudimental Eph/ephrin signaling as they have an Eph-/ephrin-like pair and homologs of downstream-signaling genes; 2) both forward- and reverse-downstream signaling might already occur in Porifera since sponges have most genes involved in these types of signaling; 3) the nonvertebrate metazoan Eph is a type-B receptor that can bind ephrins regardless of their membrane-anchoring structure, glycosylphosphatidylinositol, or transmembrane; 4) Eph/ephrin cross-class binding is specific to Gnathostomata; and 5) kinase-dead Eph receptors can be traced back to Gnathostomata. We conclude that Eph/ephrin signaling is of older origin than previously believed. We also examined the presence of protein domains associated with functional characteristics and the appearance and conservation of downstream-signaling pathways to understand the original and derived functions of Ephs and ephrins. We find that the evolutionary history of these gene families points to an ancestral function in cell–cell interactions that could contribute to the emergence of multicellularity and, in particular, to the required segregation of cell populations.
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Affiliation(s)
- Aida Arcas
- Instituto de Neurociencias (CSIC-UMH), Avda, San Juan de Alicante, Spain
| | - David G Wilkinson
- Neural Development Laboratory, The Francis Crick Institute, London, United Kingdom
| | - M Ángela Nieto
- Instituto de Neurociencias (CSIC-UMH), Avda, San Juan de Alicante, Spain
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10
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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: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [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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11
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Dionne U, Chartier FJM, López de Los Santos Y, Lavoie N, Bernard DN, Banerjee SL, Otis F, Jacquet K, Tremblay MG, Jain M, Bourassa S, Gish GD, Gagné JP, Poirier GG, Laprise P, Voyer N, Landry CR, Doucet N, Bisson N. Direct Phosphorylation of SRC Homology 3 Domains by Tyrosine Kinase Receptors Disassembles Ligand-Induced Signaling Networks. Mol Cell 2018; 70:995-1007.e11. [PMID: 29910111 PMCID: PMC6014926 DOI: 10.1016/j.molcel.2018.05.013] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 03/20/2018] [Accepted: 05/10/2018] [Indexed: 11/23/2022]
Abstract
Phosphotyrosine (pTyr) signaling has evolved into a key cell-to-cell communication system. Activated receptor tyrosine kinases (RTKs) initiate several pTyr-dependent signaling networks by creating the docking sites required for the assembly of protein complexes. However, the mechanisms leading to network disassembly and its consequence on signal transduction remain essentially unknown. We show that activated RTKs terminate downstream signaling via the direct phosphorylation of an evolutionarily conserved Tyr present in most SRC homology (SH) 3 domains, which are often part of key hub proteins for RTK-dependent signaling. We demonstrate that the direct EPHA4 RTK phosphorylation of adaptor protein NCK SH3s at these sites results in the collapse of signaling networks and abrogates their function. We also reveal that this negative regulation mechanism is shared by other RTKs. Our findings uncover a conserved mechanism through which RTKs rapidly and reversibly terminate downstream signaling while remaining in a catalytically active state on the plasma membrane.
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Affiliation(s)
- Ugo Dionne
- Centre de Recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Axe 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 Québec-Université Laval, Axe 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
| | - Yossef López de Los Santos
- PROTEO-Quebec Network for Research on Protein Function, Engineering, and Applications, Québec, QC, Canada; INRS-Institut Armand-Frappier, Université du Québec, Laval, QC, Canada
| | - Noémie Lavoie
- Centre de Recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Axe 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
| | - David N Bernard
- PROTEO-Quebec Network for Research on Protein Function, Engineering, and Applications, Québec, QC, Canada; INRS-Institut Armand-Frappier, Université du Québec, Laval, QC, Canada
| | - Sara L Banerjee
- Centre de Recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Axe 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 Otis
- PROTEO-Quebec Network for Research on Protein Function, Engineering, and Applications, Québec, QC, Canada; Département de Chimie, Université Laval, Québec, QC, Canada
| | - Kévin Jacquet
- Centre de Recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Axe 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
| | - Michel G Tremblay
- Centre de Recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Axe Oncologie, Québec, QC, Canada
| | - Mani Jain
- PROTEO-Quebec Network for Research on Protein Function, Engineering, and Applications, Québec, QC, Canada; Département de Biologie, Département de Biochimie, Microbiologie et Bio-informatique and Institut de Biologie Intégrative et des Systèmes, Université Laval, Québec, QC, Canada
| | - Sylvie Bourassa
- Centre de Recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Axe Oncologie, Québec, QC, Canada
| | - Gerald D Gish
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Joseph and Wolf Lebovic Health Complex, Toronto, ON, Canada
| | - Jean-Philippe Gagné
- Centre de Recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Axe 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
| | - Guy G Poirier
- Centre de Recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Axe 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; Département de Biologie Moléculaire, Biochimie Médicale et Pathologie, Université Laval, Québec, QC, Canada
| | - Patrick Laprise
- Centre de Recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Axe Oncologie, Québec, QC, Canada; Centre de Recherche sur le Cancer de l'Université Laval, Québec, QC, Canada; Département de Biologie Moléculaire, Biochimie Médicale et Pathologie, Université Laval, Québec, QC, Canada
| | - Normand Voyer
- PROTEO-Quebec Network for Research on Protein Function, Engineering, and Applications, Québec, QC, Canada; Département de Chimie, Université Laval, Québec, QC, Canada
| | - Christian R Landry
- PROTEO-Quebec Network for Research on Protein Function, Engineering, and Applications, Québec, QC, Canada; Département de Biologie, Département de Biochimie, Microbiologie et Bio-informatique and Institut de Biologie Intégrative et des Systèmes, Université Laval, Québec, QC, Canada
| | - Nicolas Doucet
- PROTEO-Quebec Network for Research on Protein Function, Engineering, and Applications, Québec, QC, Canada; INRS-Institut Armand-Frappier, Université du Québec, Laval, QC, Canada
| | - Nicolas Bisson
- Centre de Recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Axe 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; Département de Biologie Moléculaire, Biochimie Médicale et Pathologie, Université Laval, Québec, QC, Canada.
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12
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Bisson N, Wedlich D, Moss T. The p21-activated kinase Pak1 regulates induction and migration of the neural crest in Xenopus. Cell Cycle 2014; 11:1316-24. [DOI: 10.4161/cc.19685] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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13
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Variable combinations of specific ephrin ligand/Eph receptor pairs control embryonic tissue separation. PLoS Biol 2014; 12:e1001955. [PMID: 25247423 PMCID: PMC4172438 DOI: 10.1371/journal.pbio.1001955] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Accepted: 08/15/2014] [Indexed: 11/22/2022] Open
Abstract
Vertebrate embryonic cells recognize self from non-self, thus restricting repulsion at tissue boundaries, through a combination of multiple ephrins and Eph receptors, simply based on binding selectivity and asymmetric expression. Ephrins and Eph receptors are involved in the establishment of vertebrate tissue boundaries. The complexity of the system is puzzling, however in many instances, tissues express multiple ephrins and Ephs on both sides of the boundary, a situation that should in principle cause repulsion between cells within each tissue. Although co-expression of ephrins and Eph receptors is widespread in embryonic tissues, neurons, and cancer cells, it is still unresolved how the respective signals are integrated into a coherent output. We present a simple explanation for the confinement of repulsion to the tissue interface: Using the dorsal ectoderm–mesoderm boundary of the Xenopus embryo as a model, we identify selective functional interactions between ephrin–Eph pairs that are expressed in partial complementary patterns. The combined repulsive signals add up to be strongest across the boundary, where they reach sufficient intensity to trigger cell detachments. The process can be largely explained using a simple model based exclusively on relative ephrin and Eph concentrations and binding affinities. We generalize these findings for the ventral ectoderm–mesoderm boundary and the notochord boundary, both of which appear to function on the same principles. These results provide a paradigm for how developmental systems may integrate multiple cues to generate discrete local outcomes. How embryonic tissues separate from each other to shape the developing organism is a fundamental question in developmental biology. In vertebrates, this process relies on local repulsive reactions specifically generated at contacts between cells of different types. These reactions are triggered by typical repulsive cell surface cues, the ephrin ligands, and Eph receptors. However, the expression of multiple ephrins and the Eph receptors by each cell type represents a puzzle: Why is repulsion observed only at the tissue interface and not within the tissue itself? By studying three cases of separation in the early amphibian embryo, we uncover a surprisingly simple logic underlying this phenomenon, which can be explained by the selectivity of ligand–receptor interactions and by their asymmetric distribution. The system is set such that, despite generalized interactions throughout the tissues, it is only at contacts between different cell types that the overall repulsive output is sufficiently strong to overcome cell–cell adhesion. Our study may serve as paradigm for how systematic dissection of complex cellular systems can reduce them to simple laws and make them intelligible.
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14
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Evren S, Wen JWH, Luu O, Damm EW, Nagel M, Winklbauer R. EphA4-dependent Brachyury expression is required for dorsal mesoderm involution in the Xenopus gastrula. Development 2014; 141:3649-61. [PMID: 25209247 DOI: 10.1242/dev.111880] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Xenopus provides a well-studied model of vertebrate gastrulation, but a central feature, the movement of the mesoderm to the interior of the embryo, has received little attention. Here, we analyze mesoderm involution at the Xenopus dorsal blastopore lip. We show that a phase of rapid involution - peak involution - is intimately linked to an early stage of convergent extension, which involves differential cell migration in the prechordal mesoderm and a new movement of the chordamesoderm, radial convergence. The latter process depends on Xenopus Brachyury, the expression of which at the time of peak involution is controlled by signaling through the ephrin receptor, EphA4, its ligand ephrinB2 and its downstream effector p21-activated kinase. Our findings support a conserved role for Brachyury in blastopore morphogenesis.
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Affiliation(s)
- Sevan Evren
- Department of Cell and Systems Biology, University of Toronto, 25 Harbord Street, Toronto, Ontario, Canada M5S 3G5
| | - Jason W H Wen
- Department of Cell and Systems Biology, University of Toronto, 25 Harbord Street, Toronto, Ontario, Canada M5S 3G5
| | - Olivia Luu
- Department of Cell and Systems Biology, University of Toronto, 25 Harbord Street, Toronto, Ontario, Canada M5S 3G5
| | - Erich W Damm
- Department of Cell and Systems Biology, University of Toronto, 25 Harbord Street, Toronto, Ontario, Canada M5S 3G5
| | - Martina Nagel
- Department of Cell and Systems Biology, University of Toronto, 25 Harbord Street, Toronto, Ontario, Canada M5S 3G5
| | - Rudolf Winklbauer
- Department of Cell and Systems Biology, University of Toronto, 25 Harbord Street, Toronto, Ontario, Canada M5S 3G5
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15
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Livigni A, Peradziryi H, Sharov AA, Chia G, Hammachi F, Migueles RP, Sukparangsi W, Pernagallo S, Bradley M, Nichols J, Ko MSH, Brickman JM. A conserved Oct4/POUV-dependent network links adhesion and migration to progenitor maintenance. Curr Biol 2013; 23:2233-2244. [PMID: 24210613 PMCID: PMC4228055 DOI: 10.1016/j.cub.2013.09.048] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2013] [Revised: 08/19/2013] [Accepted: 09/18/2013] [Indexed: 11/19/2022]
Abstract
BACKGROUND The class V POU domain transcription factor Oct4 (Pou5f1) is a pivotal regulator of embryonic stem cell (ESC) self-renewal and reprogramming of somatic cells to induced pluripotent stem (iPS) cells. Oct4 is also an important evolutionarily conserved regulator of progenitor cell differentiation during embryonic development. RESULTS Here we examine the function of Oct4 homologs in Xenopus embryos and compare this to the role of Oct4 in maintaining mammalian embryo-derived stem cells. Based on a combination of expression profiling of Oct4/POUV-depleted Xenopus embryos and in silico analysis of existing mammalian Oct4 target data sets, we defined a set of evolutionary-conserved Oct4/POUV targets. Most of these targets were regulators of cell adhesion. This is consistent with Oct4/POUV phenotypes observed in the adherens junctions in Xenopus ectoderm, mouse embryonic, and epiblast stem cells. A number of these targets could rescue both Oct4/POUV phenotypes in cellular adhesion and multipotent progenitor cell maintenance, whereas expression of cadherins on their own could only transiently support adhesion and block differentiation in both ESC and Xenopus embryos. CONCLUSIONS Currently, the list of Oct4 transcriptional targets contains thousands of genes. Using evolutionary conservation, we identified a core set of functionally relevant factors that linked the maintenance of adhesion to Oct4/POUV. We found that the regulation of adhesion by the Oct4/POUV network occurred at both transcriptional and posttranslational levels and was required for pluripotency.
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Affiliation(s)
- Alessandra Livigni
- MRC Centre for Regenerative Medicine, Institute for Stem Cell Research, School of Biological Sciences, 5 Little France Drive, University of Edinburgh, Edinburgh EH16 4UU, UK
| | - Hanna Peradziryi
- The Danish Stem Cell Centre (DanStem), University of Copenhagen, 3B Blegdamsvej, 2200 Copenhagen, Denmark
| | - Alexei A Sharov
- Laboratory of Genetics, National Institute on Aging, NIH Biomedical Research Centre, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA
| | - Gloryn Chia
- Wellcome Trust Centre for Stem Cell Research, University of Cambridge, Tennis Court Road, Cambridge CB2 1QR, UK
| | - Fella Hammachi
- MRC Centre for Regenerative Medicine, Institute for Stem Cell Research, School of Biological Sciences, 5 Little France Drive, University of Edinburgh, Edinburgh EH16 4UU, UK
| | - Rosa Portero Migueles
- MRC Centre for Regenerative Medicine, Institute for Stem Cell Research, School of Biological Sciences, 5 Little France Drive, University of Edinburgh, Edinburgh EH16 4UU, UK
| | - Woranop Sukparangsi
- The Danish Stem Cell Centre (DanStem), University of Copenhagen, 3B Blegdamsvej, 2200 Copenhagen, Denmark
| | - Salvatore Pernagallo
- School of Chemistry, Joseph Black Building, King's Buildings, the University of Edinburgh, West Mains Road, Edinburgh EH9 3JJ, UK
| | - Mark Bradley
- School of Chemistry, Joseph Black Building, King's Buildings, the University of Edinburgh, West Mains Road, Edinburgh EH9 3JJ, UK
| | - Jennifer Nichols
- Wellcome Trust Centre for Stem Cell Research, University of Cambridge, Tennis Court Road, Cambridge CB2 1QR, UK
| | - Minoru S H Ko
- Laboratory of Genetics, National Institute on Aging, NIH Biomedical Research Centre, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA; Department of Systems Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160, Japan
| | - Joshua M Brickman
- MRC Centre for Regenerative Medicine, Institute for Stem Cell Research, School of Biological Sciences, 5 Little France Drive, University of Edinburgh, Edinburgh EH16 4UU, UK; The Danish Stem Cell Centre (DanStem), University of Copenhagen, 3B Blegdamsvej, 2200 Copenhagen, Denmark.
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16
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Santiago-Medina M, Gregus KA, Gomez TM. PAK-PIX interactions regulate adhesion dynamics and membrane protrusion to control neurite outgrowth. J Cell Sci 2013; 126:1122-33. [PMID: 23321640 DOI: 10.1242/jcs.112607] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The roles of P21-activated kinase (PAK) in the regulation of axon outgrowth downstream of extracellular matrix (ECM) proteins are poorly understood. Here we show that PAK1-3 and PIX are expressed in the developing spinal cord and differentially localize to point contacts and filopodial tips within motile growth cones. Using a specific interfering peptide called PAK18, we found that axon outgrowth is robustly stimulated on laminin by partial inhibition of PAK-PIX interactions and PAK function, whereas complete inhibition of PAK function stalls axon outgrowth. Furthermore, modest inhibition of PAK-PIX stimulates the assembly and turnover of growth cone point contacts, whereas strong inhibition over-stabilizes adhesions. Point mutations within PAK confirm the importance of PIX binding. Together our data suggest that regulation of PAK-PIX interactions in growth cones controls neurite outgrowth by influencing the activity of several important mediators of actin filament polymerization and retrograde flow, as well as integrin-dependent adhesion to laminin.
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Affiliation(s)
- Miguel Santiago-Medina
- Department of Neuroscience, Neuroscience Training Program, University of Wisconsin, Madison, WI 53706, USA
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17
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Saintigny P, Peng S, Zhang L, Sen B, Wistuba II, Lippman SM, Girard L, Minna JD, Heymach JV, Johnson FM. Global evaluation of Eph receptors and ephrins in lung adenocarcinomas identifies EphA4 as an inhibitor of cell migration and invasion. Mol Cancer Ther 2012; 11:2021-32. [PMID: 22807579 DOI: 10.1158/1535-7163.mct-12-0030] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The Eph family of receptors is the largest family of receptor tyrosine kinases, but it remains poorly studied in lung cancer. We aimed to systematically explore the human Eph receptors and their ligands, the ephrins, in lung adenocarcinoma. The prognostic impact of Eph receptor and ephrin gene expression was analyzed using 2 independent cohorts of lung adenocarcinoma. Gene expression profiles in lung adenocarcinoma compared with normal adjacent lung were studied in 3 independent cohorts and in cell lines. Gene expression profiles were validated with quantitative polymerase chain reaction (qPCR) and Western blotting in cell lines. Functional studies to assess the role of Eph receptor A4 (EphA4) were carried out in vitro. The biological effects of EphA4 in lung cancer cell lines were assayed following overexpression and knockdown. Of the 11 Eph receptors and 8 ephrins analyzed, only EphA4 and ephrin A1 gene expression were consistently associated with an improved outcome in patients with lung adenocarcinoma. Expression levels of EphA4 by microarray correlated well with expression levels measured by qPCR and Western blotting. EphA4 overexpression reduced cell migration and invasion but did not affect cell cycle, apoptosis, or drug sensitivity. Surprisingly, EphA4 was expressed at higher levels in cancer compared with non-cancer tissues and cell lines. EphA4 gene expression is associated with an improved outcome in patients with resected lung adenocarcinoma, possibly by affecting cancer cell migration and invasion.
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Affiliation(s)
- Pierre Saintigny
- Department of 1Thoracic/Head & Neck Medical Oncology, The University of Texas MD Anderson Cancer Center;5The University of Texas Graduate School of Biomedical Sciences, Houston, TX 77030, USA.
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18
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Jean S, Tremblay MG, Herdman C, Guillou F, Moss T. The endocytic adapter E-Syt2 recruits the p21 GTPase activated kinase PAK1 to mediate actin dynamics and FGF signalling. Biol Open 2012; 1:731-8. [PMID: 23213466 PMCID: PMC3507230 DOI: 10.1242/bio.2012968] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2012] [Accepted: 05/14/2012] [Indexed: 12/20/2022] Open
Abstract
Fibroblast growth factor (FGF) signalling plays an essential role in early vertebrate development. However, the response to FGF requires endocytosis of the activated FGF receptor (FGFR) that is in part dependent on remodelling of the actin cytoskeleton. Recently we showed that the extended synaptotagmin family plasma membrane protein, E-Syt2, is an essential endocytic adapter for FGFR1. Here we show E-Syt2 is also an interaction partner for the p21-GTPase Activated Kinase PAK1. The phospholipid binding C2C domain of E-Syt2 specifically binds a site adjacent to the CRIB/GBD of PAK1. PAK1 and E-Syt2 selectively complex with FGFR1 and functionally cooperate in the FGF signalling. E-Syt2 binding suppresses actin polymerization and inhibits the activation of PAK1 by the GTPases Cdc42 and Rac. Interestingly, the E-Syt2 binding site on PAK1 extensively overlaps a site recently suggested to bind phospholipids. Our data suggest that PAK1 interacts with phospholipid membrane domains via E-Syt2, where it may cooperate in the E-Syt2-dependent endocytosis of activated FGFR1 by modulating cortical actin stability.
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Affiliation(s)
- Steve Jean
- Present address: Division of Biological Sciences, University of California, San Diego, La Jolla, CA 92093-0380, USA
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19
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Nievergall E, Lackmann M, Janes PW. Eph-dependent cell-cell adhesion and segregation in development and cancer. Cell Mol Life Sci 2012; 69:1813-42. [PMID: 22204021 PMCID: PMC11114713 DOI: 10.1007/s00018-011-0900-6] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2011] [Revised: 11/06/2011] [Accepted: 11/28/2011] [Indexed: 01/23/2023]
Abstract
Numerous studies attest to essential roles for Eph receptors and their ephrin ligands in controlling cell positioning and tissue patterning during normal and oncogenic development. These studies suggest multiple, sometimes contradictory, functions of Eph-ephrin signalling, which under different conditions can promote either spreading and cell-cell adhesion or cytoskeletal collapse, cell rounding, de-adhesion and cell-cell segregation. A principle determinant of the balance between these two opposing responses is the degree of receptor/ligand clustering and activation. This equilibrium is likely altered in cancers and modulated by somatic mutations of key Eph family members that have emerged as candidate cancer markers in recent profiling studies. In addition, cross-talk amongst Ephs and with other signalling pathways significantly modulates cell-cell adhesion, both between and within Eph- and ephrin-expressing cell populations. This review summarises our current understanding of how Eph receptors control cell adhesion and morphology, and presents examples demonstrating the importance of these events in normal development and cancer.
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Affiliation(s)
- Eva Nievergall
- Department of Biochemistry and Molecular Biology, Monash University, Wellington Road, Clayton, VIC 3800 Australia
- Present Address: Haematology Department, SA Pathology, Frome Road, Adelaide, SA 5000 Australia
| | - Martin Lackmann
- Department of Biochemistry and Molecular Biology, Monash University, Wellington Road, Clayton, VIC 3800 Australia
| | - Peter W. Janes
- Department of Biochemistry and Molecular Biology, Monash University, Wellington Road, Clayton, VIC 3800 Australia
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20
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Mohamed AM, Boudreau JR, Yu FPS, Liu J, Chin-Sang ID. The Caenorhabditis elegans Eph receptor activates NCK and N-WASP, and inhibits Ena/VASP to regulate growth cone dynamics during axon guidance. PLoS Genet 2012; 8:e1002513. [PMID: 22383893 PMCID: PMC3285579 DOI: 10.1371/journal.pgen.1002513] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2011] [Accepted: 12/13/2011] [Indexed: 01/18/2023] Open
Abstract
The Eph receptor tyrosine kinases (RTKs) are regulators of cell migration and axon guidance. However, our understanding of the molecular mechanisms by which Eph RTKs regulate these processes is still incomplete. To understand how Eph receptors regulate axon guidance in Caenorhabditis elegans, we screened for suppressors of axon guidance defects caused by a hyperactive VAB-1/Eph RTK. We identified NCK-1 and WSP-1/N-WASP as downstream effectors of VAB-1. Furthermore, VAB-1, NCK-1, and WSP-1 can form a complex in vitro. We also report that NCK-1 can physically bind UNC-34/Enabled (Ena), and suggest that VAB-1 inhibits the NCK-1/UNC-34 complex and negatively regulates UNC-34. Our results provide a model of the molecular events that allow the VAB-1 RTK to regulate actin dynamics for axon guidance. We suggest that VAB-1/Eph RTK can stop axonal outgrowth by inhibiting filopodia formation at the growth cone by activating Arp2/3 through a VAB-1/NCK-1/WSP-1 complex and by inhibiting UNC-34/Ena activity. The correct wiring of the nervous system depends on the ability of axons to properly interpret extracellular cues that guide them to their targets. The Eph receptor tyrosine kinases (RTKs) have roles in guiding axons, but their signaling pathways are not completely understood. In this study, we used the nematode Caenorhabditis elegans to study how the VAB-1 Eph RTK regulates the growth cone structure for axon guidance. Genetic and molecular data show that VAB-1 regulates the conserved molecules NCK-1, WSP-1/N-WASP, and UNC-34/Ena. Our study provides a model of how the VAB-1 Eph RTK modulates the growth cone structure to inhibit axonal outgrowth. We show that activated VAB-1 can inhibit an NCK-1/UNC-34 interaction by binding to the NCK-1 SH2 domain. We also show that NCK-1 and WSP-1 can physically interact and that VAB-1/NCK-1 and WSP-1 form a complex in vitro. We suggest that the VAB-1 Eph RTK can contribute to the termination of axon outgrowth by two methods: 1) The VAB-1/NCK-1/WSP-1 complex activates ARP-2/3 to change the actin growth cone dynamics to that of a branched structure thus reducing the number of filopodia, and 2) VAB-1 inhibits axon extension by inhibiting UNC-34/Ena's function in actin polymerization.
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Affiliation(s)
| | | | | | - Jun Liu
- Department of Biology, Queen's University, Kingston, Canada
| | - Ian D. Chin-Sang
- Department of Biology, Queen's University, Kingston, Canada
- * E-mail:
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21
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Singh A, Winterbottom E, Daar IO. Eph/ephrin signaling in cell-cell and cell-substrate adhesion. Front Biosci (Landmark Ed) 2012; 17:473-97. [PMID: 22201756 DOI: 10.2741/3939] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Cell-cell and cell-matrix adhesion are critical processes for the formation and maintenance of tissue patterns during development, as well as control of invasion and metastasis of cancer cells. Although great strides have been made regarding our understanding of the processes that play a role in cell adhesion and cell movement, the precise mechanisms by which diverse signaling events regulate cell and tissue architecture are poorly understood. One group of cell surface molecules, Eph receptor tyrosine kinases, and their membrane-bound ligands, ephrins, are key regulators in these processes. It is the ability of Eph/ephrin signaling pathways to regulate cell-cell adhesion and motility that establishes this family as a formidable system for regulating tissue separation and morphogenesis. Moreover, the de-regulation of this signaling system is linked to the promotion of more aggressive and metastatic tumors in humans.
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Affiliation(s)
- Arvinder Singh
- Laboratory of Cell and Developmental Signaling, National Cancer Institute-Frederick, Frederick, Maryland 21702, USA
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22
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Leushacke M, Spörle R, Bernemann C, Brouwer-Lehmitz A, Fritzmann J, Theis M, Buchholz F, Herrmann BG, Morkel M. An RNA interference phenotypic screen identifies a role for FGF signals in colon cancer progression. PLoS One 2011; 6:e23381. [PMID: 21853123 PMCID: PMC3154943 DOI: 10.1371/journal.pone.0023381] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2011] [Accepted: 07/15/2011] [Indexed: 12/19/2022] Open
Abstract
In tumor cells, stepwise oncogenic deregulation of signaling cascades induces alterations of cellular morphology and promotes the acquisition of malignant traits. Here, we identified a set of 21 genes, including FGF9, as determinants of tumor cell morphology by an RNA interference phenotypic screen in SW480 colon cancer cells. Using a panel of small molecular inhibitors, we subsequently established phenotypic effects, downstream signaling cascades, and associated gene expression signatures of FGF receptor signals. We found that inhibition of FGF signals induces epithelial cell adhesion and loss of motility in colon cancer cells. These effects are mediated via the mitogen-activated protein kinase (MAPK) and Rho GTPase cascades. In agreement with these findings, inhibition of the MEK1/2 or JNK cascades, but not of the PI3K-AKT signaling axis also induced epithelial cell morphology. Finally, we found that expression of FGF9 was strong in a subset of advanced colon cancers, and overexpression negatively correlated with patients' survival. Our functional and expression analyses suggest that FGF receptor signals can contribute to colon cancer progression.
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Affiliation(s)
- Marc Leushacke
- Department of Developmental Genetics, Max Planck Institute for Molecular Genetics, Berlin, Germany
- Department of Biology, Chemistry and Pharmacy, Free University Berlin, Berlin, Germany
| | - Ralf Spörle
- Department of Developmental Genetics, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - Christof Bernemann
- Department of Developmental Genetics, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - Antje Brouwer-Lehmitz
- Department of Developmental Genetics, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - Johannes Fritzmann
- Max Delbrück Center for Molecular Medicine, Berlin, Germany
- Department of Surgery, Heidelberg University Hospital, Heidelberg, Germany
| | - Mirko Theis
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
- University Hospital Carl Gustav Carus and Medical Faculty, University of Technology Dresden, Dresden, Germany
| | - Frank Buchholz
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
- University Hospital Carl Gustav Carus and Medical Faculty, University of Technology Dresden, Dresden, Germany
| | - Bernhard G. Herrmann
- Department of Developmental Genetics, Max Planck Institute for Molecular Genetics, Berlin, Germany
- Institute for Medical Genetics, Charité Campus Benjamin Franklin, Berlin, Germany
| | - Markus Morkel
- Department of Developmental Genetics, Max Planck Institute for Molecular Genetics, Berlin, Germany
- * E-mail:
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23
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The involvement of Eph–Ephrin signaling in tissue separation and convergence during Xenopus gastrulation movements. Dev Biol 2011; 350:441-50. [DOI: 10.1016/j.ydbio.2010.12.012] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2009] [Revised: 12/03/2010] [Accepted: 12/03/2010] [Indexed: 11/21/2022]
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Kumar A, Molli PR, Pakala SB, Bui Nguyen TM, Rayala SK, Kumar R. PAK thread from amoeba to mammals. J Cell Biochem 2009; 107:579-85. [PMID: 19350548 DOI: 10.1002/jcb.22159] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The p21-activated kinases (PAKs) are signaling nodes that play a crucial role in cellular processes including cell motility, differentiation, survival, gene transcription, and hormone signaling. PAKs are highly conserved family of serine-threonine kinases that act as effector for small GTPases Rac and Cdc42. Most of our knowledge about PAK functions has been derived from genetic approaches in lower organisms and many of these functions are similar to that seen in mammalian cells. In this review, we have summarized the extensive information generated in lower eukaryotes and very briefly discussed the current status of PAKs in humans.
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Affiliation(s)
- Anupam Kumar
- Department of Biochemistry and Molecular Biology, George Washington University Medical Center, Washington, District of Columbia 20037, USA
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25
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Nagel M, Luu O, Bisson N, Macanovic B, Moss T, Winklbauer R. Role of p21-activated kinase in cell polarity and directional mesendoderm migration in the Xenopus gastrula. Dev Dyn 2009; 238:1709-26. [PMID: 19504461 DOI: 10.1002/dvdy.21985] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The p21 activated kinases (Paks) are prominently involved in the regulation of cell motility. Using a kinase-dead mutant of xPak1, we show that during Xenopus gastrulation, the kinase activity of Pak1 is required upstream of Cdc42 for the establishment of cell polarity in the migrating mesendoderm. Overactivation of Pak1 function by the expression of constitutively active xPak1 compromises the maintenance of cell polarity, by indirectly inhibiting RhoA function. Inhibition of cell polarization does not affect the migration of single mesendoderm cells. However, Pak1 inhibition interferes with the guidance of mesendoderm migration by directional cues residing in the extracellular matrix of the blastocoel roof, and with mesendoderm translocation in the embryo.
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Affiliation(s)
- Martina Nagel
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
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Nie S, Kee Y, Bronner-Fraser M. Myosin-X is critical for migratory ability of Xenopus cranial neural crest cells. Dev Biol 2009; 335:132-42. [PMID: 19712673 DOI: 10.1016/j.ydbio.2009.08.018] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2009] [Revised: 08/18/2009] [Accepted: 08/18/2009] [Indexed: 01/26/2023]
Abstract
The neural crest is a highly migratory cell population, unique to vertebrates, that forms much of the craniofacial skeleton and peripheral nervous system. In exploring the cell biological basis underlying this behavior, we have identified an unconventional myosin, myosin-X (Myo10) that is required for neural crest migration. Myo10 is highly expressed in both premigratory and migrating cranial neural crest (CNC) cells in Xenopus embryos. Disrupting Myo10 expression using antisense morpholino oligonucleotides leads to impaired neural crest migration and subsequent cartilage formation, but only a slight delay in induction. In vivo grafting experiments reveal that Myo10-depleted CNC cells migrate a shorter distance and fail to segregate into distinct migratory streams. Finally, in vitro cultures and cell dissociation-reaggregation assays suggest that Myo10 may be critical for cell protrusion and cell-cell adhesion. These results demonstrate an essential role for Myo10 in normal cranial neural crest migration and suggest a link to cell-cell interactions and formation of processes.
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Affiliation(s)
- Shuyi Nie
- Division of Biology 139-74, California Institute of Technology, Pasadena, CA 91125, USA
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Abstract
Signal relay by guidance receptors at the axonal growth cone is a process essential for the assembly of a functional nervous system. We investigated the in vivo function of Src family kinases (SFKs) as growth cone guidance signaling intermediates in the context of spinal lateral motor column (LMC) motor axon projection toward the ventral or dorsal limb mesenchyme. Using in situ mRNA detection we determined that Src and Fyn are expressed in LMC motor neurons of chick and mouse embryos at the time of limb trajectory selection. Inhibition of SFK activity by C-terminal Src kinase (Csk) overexpression in chick LMC axons using in ovo electroporation resulted in LMC axons selecting the inappropriate dorsoventral trajectory within the limb mesenchyme, with medial LMC axon projecting into the dorsal and ventral limb nerve with apparently random incidence. We also detected LMC axon trajectory choice errors in Src mutant mice demonstrating a nonredundant role for Src in motor axon guidance in agreement with gain and loss of Src function in chick LMC neurons which led to the redirection of LMC axons. Finally, Csk-mediated SFK inhibition attenuated the retargeting of LMC axons caused by EphA or EphB over-expression, implying the participation of SFKs in Eph-mediated LMC motor axon guidance. In summary, our findings demonstrate that SFKs are essential for motor axon guidance and suggest that they play an important role in relaying ephrin:Eph signals that mediate the selection of motor axon trajectory in the limb.
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28
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Winklbauer R. Cell adhesion in amphibian gastrulation. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2009; 278:215-75. [PMID: 19815180 DOI: 10.1016/s1937-6448(09)78005-0] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The amphibian gastrula can be regarded as a single coherent tissue which folds and distorts itself in a reproducible pattern to establish the embryonic germ layers. It is held together by cadherins which provide the flexible adhesion required for the massive cell rearrangements that accompany gastrulation. Cadherin expression and adhesiveness increase as one goes from the vegetal cell mass through the anterior mesendoderm to the chordamesoderm, and then decrease again slightly in the ectoderm. Together with a basic random component of cell motility, this flexible, differentially expressed adhesiveness generates surface and interfacial tension effects which, in principle, can exert strong forces. However, conclusive evidence for an in vivo role of differential adhesion-related effects in gastrula morphogenesis is still lacking. The most important morphogenetic process in the amphibian gastrula seems to be intercellular migration, where cells crawl actively across each other's surface. The crucial aspect of this process is that cell motility is globally oriented, leading for example to mediolateral intercalation of bipolar cells during convergent extension of the chordamesoderm or to the directional migration of unipolar cells during translocation of the anterior mesendoderm on the ectodermal blastocoel roof. During these movements, the boundary between ectoderm and mesoderm is maintained by a tissue separation process.
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Affiliation(s)
- Rudolf Winklbauer
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario M5S 3G5, Canada
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Fawcett JP, Georgiou J, Ruston J, Bladt F, Sherman A, Warner N, Saab BJ, Scott R, Roder JC, Pawson T. Nck adaptor proteins control the organization of neuronal circuits important for walking. Proc Natl Acad Sci U S A 2007; 104:20973-8. [PMID: 18093944 PMCID: PMC2409251 DOI: 10.1073/pnas.0710316105] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2007] [Indexed: 01/15/2023] Open
Abstract
The intracellular signaling targets used by mammalian axon guidance receptors to organize the nervous system in vivo are unclear. The Nck1 and Nck2 SH2/SH3 adaptors (collectively Nck) can couple phosphotyrosine (pTyr) signals to reorganization of the actin cytoskeleton and are therefore candidates for linking guidance cues to the regulatory machinery of the cytoskeleton. We find that selective inactivation of Nck in the murine nervous system causes a hopping gait and a defect in the spinal central pattern generator, which is characterized by synchronous firing of bilateral ventral motor neurons. Nck-deficient mice also show abnormal projections of corticospinal tract axons and defective development of the posterior tract of the anterior commissure. These phenotypes are consistent with a role for Nck in signaling initiated by different classes of guidance receptors, including the EphA4 receptor tyrosine kinase. Our data indicate that Nck adaptors couple pTyr guidance signals to cytoskeletal events required for the ipsilateral projections of spinal cord neurons and thus for normal limb movement.
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Affiliation(s)
- James P. Fawcett
- *Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON, Canada M5G 1X5
- Departments of Pharmacology and Surgery, Dalhousie University, 5850 College Street, Halifax, NS, Canada B3H 1X5
| | - John Georgiou
- *Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON, Canada M5G 1X5
| | - Julie Ruston
- *Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON, Canada M5G 1X5
| | - Friedhelm Bladt
- *Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON, Canada M5G 1X5
| | - Andrew Sherman
- *Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON, Canada M5G 1X5
- Department of Medical Genetics and Microbiology, University of Toronto, 1 Kings College Circle, Toronto, ON, Canada M5S 1A8; and
| | - Neil Warner
- *Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON, Canada M5G 1X5
- Department of Medical Genetics and Microbiology, University of Toronto, 1 Kings College Circle, Toronto, ON, Canada M5S 1A8; and
| | - Bechara J. Saab
- *Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON, Canada M5G 1X5
- Department of Medical Genetics and Microbiology, University of Toronto, 1 Kings College Circle, Toronto, ON, Canada M5S 1A8; and
| | - Rizaldy Scott
- *Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON, Canada M5G 1X5
| | - John C. Roder
- *Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON, Canada M5G 1X5
- Department of Medical Genetics and Microbiology, University of Toronto, 1 Kings College Circle, Toronto, ON, Canada M5S 1A8; and
| | - Tony Pawson
- *Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON, Canada M5G 1X5
- Department of Medical Genetics and Microbiology, University of Toronto, 1 Kings College Circle, Toronto, ON, Canada M5S 1A8; and
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30
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Wegmeyer H, Egea J, Rabe N, Gezelius H, Filosa A, Enjin A, Varoqueaux F, Deininger K, Schnütgen F, Brose N, Klein R, Kullander K, Betz A. EphA4-Dependent Axon Guidance Is Mediated by the RacGAP α2-Chimaerin. Neuron 2007; 55:756-67. [PMID: 17785182 DOI: 10.1016/j.neuron.2007.07.038] [Citation(s) in RCA: 125] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2007] [Revised: 07/20/2007] [Accepted: 07/30/2007] [Indexed: 01/19/2023]
Abstract
Neuronal network formation in the developing nervous system is dependent on the accurate navigation of nerve cell axons and dendrites, which is controlled by attractive and repulsive guidance cues. Ephrins and their cognate Eph receptors mediate many repulsive axonal guidance decisions by intercellular interactions resulting in growth cone collapse and axon retraction of the Eph-presenting neuron. We show that the Rac-specific GTPase-activating protein alpha2-chimaerin binds activated EphA4 and mediates EphA4-triggered axonal growth cone collapse. alpha-Chimaerin mutant mice display a phenotype similar to that of EphA4 mutant mice, including aberrant midline axon guidance and defective spinal cord central pattern generator activity. Our results reveal an alpha-chimaerin-dependent signaling pathway downstream of EphA4, which is essential for axon guidance decisions and neuronal circuit formation in vivo.
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Affiliation(s)
- Heike Wegmeyer
- Department of Molecular Neurobiology and DFG Center for Molecular Physiology of the Brain, Max Planck Institute of Experimental Medicine, D-37075 Göttingen, Germany
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