1
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Li S, Li J, Yang X, Huang J, Feng S, Xie Z, Yang N, Wang Y, Zhou N. Peripheral nervous system lymphatic vessels: A simple delivery route to promote nerve regeneration. Exp Neurol 2024; 377:114783. [PMID: 38688418 DOI: 10.1016/j.expneurol.2024.114783] [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: 12/11/2023] [Revised: 03/09/2024] [Accepted: 04/18/2024] [Indexed: 05/02/2024]
Abstract
The structural and functional features of lymphatic vessels in the peripheral nervous system (pLVs) is still unclear. Here, we clarify the existence of pLVs in rats, PROX1-EGFP transgenic mice and human, and exhibit a clear three-dimensional structure for helping understand its structural features. Moreover, two specific phenotypes of lymphatics endothelial cells (Rnd1Hi LECs and Ccl21Hi LECs) in peripheral nerves are well characterized by single-cell sequencing. Subsequently, the ability of trans-lymphatic delivery to peripheral nerves via pLVs has been dynamically demonstrated. After peripheral nerve injury (PNI), extensive lymphangiogenesis occurs in the lesion area and further enhances the efficiency of retrograde lymphatic-nerve transport. In PNI animal models, subcutaneously footpad-injected exosomes are efficiently delivered to sciatic nerve via pLVs which can promote nerve regeneration. The trans-lymphatic delivery to peripheral nerves via pLVs can subtly bypass BNB which provides an easy and alternative delivery route for PNI treatment.
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Affiliation(s)
- Senrui Li
- Department of Orthopedics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou 450052, China
| | - Jiangnan Li
- Department of Orthopedics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou 450052, China
| | - Xiaoqi Yang
- Department of Orthopedics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou 450052, China; State Key Laboratory of Drug Research, Molecular Imaging Center, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Jinsheng Huang
- Department of Orthopedics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou 450052, China
| | - Shuai Feng
- Department of Hand and Podiatric Surgery, Henan Provincial People's Hospital, Zhengzhou 450000, China
| | - Zhenjun Xie
- Department of Hand and Podiatric Surgery, Henan Provincial People's Hospital, Zhengzhou 450000, China
| | - Ningning Yang
- Department of Emergency, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou 450052, China.
| | - Yuanyi Wang
- Department of Spinal Surgery, The First Hospital of Jilin University, Orthopedics Center, Jilin University, Changchun 130021, China.
| | - Nan Zhou
- Department of Orthopedics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou 450052, China.
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2
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Abushalbaq O, Baek J, Yaron A, Tran TS. Balancing act of small GTPases downstream of plexin-A4 signaling motifs promotes dendrite elaboration in mammalian cortical neurons. Sci Signal 2024; 17:eadh7673. [PMID: 38227686 DOI: 10.1126/scisignal.adh7673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 12/21/2023] [Indexed: 01/18/2024]
Abstract
The precise development of neuronal morphologies is crucial to the establishment of synaptic circuits and, ultimately, proper brain function. Signaling by the axon guidance cue semaphorin 3A (Sema3A) and its receptor complex of neuropilin-1 and plexin-A4 has multifunctional outcomes in neuronal morphogenesis. Downstream activation of the RhoGEF FARP2 through interaction with the lysine-arginine-lysine motif of plexin-A4 and consequent activation of the small GTPase Rac1 promotes dendrite arborization, but this pathway is dispensable for axon repulsion. Here, we investigated the interplay of small GTPase signaling mechanisms underlying Sema3A-mediated dendritic elaboration in mouse layer V cortical neurons in vitro and in vivo. Sema3A promoted the binding of the small GTPase Rnd1 to the amino acid motif lysine-valine-serine (LVS) in the cytoplasmic domain of plexin-A4. Rnd1 inhibited the activity of the small GTPase RhoA and the kinase ROCK, thus supporting the activity of the GTPase Rac1, which permitted the growth and branching of dendrites. Overexpression of a dominant-negative RhoA, a constitutively active Rac1, or the pharmacological inhibition of ROCK activity rescued defects in dendritic elaboration in neurons expressing a plexin-A4 mutant lacking the LVS motif. Our findings provide insights into the previously unappreciated balancing act between Rho and Rac signaling downstream of specific motifs in plexin-A4 to mediate Sema3A-dependent dendritic elaboration in mammalian cortical neuron development.
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Affiliation(s)
- Oday Abushalbaq
- Department of Biological Sciences, Rutgers University, Newark, NJ 07102, USA
| | - Jiyeon Baek
- Department of Biological Sciences, Rutgers University, Newark, NJ 07102, USA
| | - Avraham Yaron
- Department of Biomolecular Sciences and Department of Molecular Neuroscience, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Tracy S Tran
- Department of Biological Sciences, Rutgers University, Newark, NJ 07102, USA
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3
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Tomé D, Dias MS, Correia J, Almeida RD. Fibroblast growth factor signaling in axons: from development to disease. Cell Commun Signal 2023; 21:290. [PMID: 37845690 PMCID: PMC10577959 DOI: 10.1186/s12964-023-01284-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Accepted: 08/18/2023] [Indexed: 10/18/2023] Open
Abstract
The fibroblast growth factor (FGF) family regulates various and important aspects of nervous system development, ranging from the well-established roles in neuronal patterning to more recent and exciting functions in axonal growth and synaptogenesis. In addition, FGFs play a critical role in axonal regeneration, particularly after spinal cord injury, confirming their versatile nature in the nervous system. Due to their widespread involvement in neural development, the FGF system also underlies several human neurological disorders. While particular attention has been given to FGFs in a whole-cell context, their effects at the axonal level are in most cases undervalued. Here we discuss the endeavor of the FGF system in axons, we delve into this neuronal subcompartment to provide an original view of this multipurpose family of growth factors in nervous system (dys)function. Video Abstract.
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Affiliation(s)
- Diogo Tomé
- Institute of Biomedicine, Department of Medical Sciences - iBiMED, University of Aveiro, Aveiro, Portugal
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Marta S Dias
- Institute of Biomedicine, Department of Medical Sciences - iBiMED, University of Aveiro, Aveiro, Portugal
| | - Joana Correia
- Institute of Biomedicine, Department of Medical Sciences - iBiMED, University of Aveiro, Aveiro, Portugal
| | - Ramiro D Almeida
- Institute of Biomedicine, Department of Medical Sciences - iBiMED, University of Aveiro, Aveiro, Portugal.
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.
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4
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Kumar A, Mishra S, Kumar A, Raut AA, Sato S, Takaoka A, Kumar H. Essential role of Rnd1 in innate immunity during viral and bacterial infections. Cell Death Dis 2022; 13:520. [PMID: 35654795 PMCID: PMC9161769 DOI: 10.1038/s41419-022-04954-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Revised: 05/05/2022] [Accepted: 05/13/2022] [Indexed: 01/21/2023]
Abstract
Intracellular and cell surface pattern-recognition receptors (PRRs) are an essential part of innate immune recognition and host defense. Here, we have compared the innate immune responses between humans and bats to identify a novel membrane-associated protein, Rnd1, which defends against viral and bacterial infection in an interferon-independent manner. Rnd1 belongs to the Rho GTPase family, but unlike other small GTPase members, it is constitutively active. We show that Rnd1 is induced by pro-inflammatory cytokines during viral and bacterial infections and provides protection against these pathogens through two distinct mechanisms. Rnd1 counteracts intracellular calcium fluctuations by inhibiting RhoA activation, thereby inhibiting virus internalisation. On the other hand, Rnd1 also facilitates pro-inflammatory cytokines IL-6 and TNF-α through Plxnb1, which are highly effective against intracellular bacterial infections. These data provide a novel Rnd1-mediated innate defense against viral and bacterial infections.
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Affiliation(s)
- Akhilesh Kumar
- grid.462376.20000 0004 1763 8131Department of Biological Sciences, Indian Institute of Science Education and Research Bhopal, Bhopal, India
| | - Shalabh Mishra
- grid.462376.20000 0004 1763 8131Department of Biological Sciences, Indian Institute of Science Education and Research Bhopal, Bhopal, India
| | - Ashish Kumar
- grid.462376.20000 0004 1763 8131Department of Biological Sciences, Indian Institute of Science Education and Research Bhopal, Bhopal, India ,grid.27860.3b0000 0004 1936 9684Department of Dermatology, School of Medicine, University of California Davis, Sacramento, CA USA
| | - Ashwin Ashok Raut
- grid.506025.40000 0004 5997 407XPathogenomics Lab, ICAR-National Institute of High Security Animal Diseases, Bhopal, Madhya Pradesh India
| | - Seiichi Sato
- grid.39158.360000 0001 2173 7691Division of Signaling in Cancer and Immunology, Institute for Genetic Medicine, Hokkaido University, Sapporo, Japan
| | - Akinori Takaoka
- grid.39158.360000 0001 2173 7691Division of Signaling in Cancer and Immunology, Institute for Genetic Medicine, Hokkaido University, Sapporo, Japan
| | - Himanshu Kumar
- grid.462376.20000 0004 1763 8131Department of Biological Sciences, Indian Institute of Science Education and Research Bhopal, Bhopal, India ,grid.136593.b0000 0004 0373 3971WPI Immunology, Frontier Research Centre, Osaka University, Osaka, Japan
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5
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Higgs VE, Das RM. Establishing neuronal polarity: microtubule regulation during neurite initiation. OXFORD OPEN NEUROSCIENCE 2022; 1:kvac007. [PMID: 38596701 PMCID: PMC10913830 DOI: 10.1093/oons/kvac007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 04/25/2022] [Accepted: 05/02/2022] [Indexed: 04/11/2024]
Abstract
The initiation of nascent projections, or neurites, from the neuronal cell body is the first stage in the formation of axons and dendrites, and thus a critical step in the establishment of neuronal architecture and nervous system development. Neurite formation relies on the polarized remodelling of microtubules, which dynamically direct and reinforce cell shape, and provide tracks for cargo transport and force generation. Within neurons, microtubule behaviour and structure are tightly controlled by an array of regulatory factors. Although microtubule regulation in the later stages of axon development is relatively well understood, how microtubules are regulated during neurite initiation is rarely examined. Here, we discuss how factors that direct microtubule growth, remodelling, stability and positioning influence neurite formation. In addition, we consider microtubule organization by the centrosome and modulation by the actin and intermediate filament networks to provide an up-to-date picture of this vital stage in neuronal development.
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Affiliation(s)
- Victoria E Higgs
- Division of Molecular and Cellular Function, Faculty of Biology, Medicine and Health, University of Manchester, Oxford Road, Manchester M13 9PT, UK
| | - Raman M Das
- Division of Molecular and Cellular Function, Faculty of Biology, Medicine and Health, University of Manchester, Oxford Road, Manchester M13 9PT, UK
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6
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Biological Significance and Targeting of the FGFR Axis in Cancer. Cancers (Basel) 2021; 13:cancers13225681. [PMID: 34830836 PMCID: PMC8616401 DOI: 10.3390/cancers13225681] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 11/08/2021] [Accepted: 11/11/2021] [Indexed: 12/15/2022] Open
Abstract
Simple Summary All cells within tissues and organ systems must communicate with each other to ensure they function in a coordinated manner. One form of communication is signalling mediated by small proteins (for example fibroblast growth factors; FGFs) that are secreted by one cell and bind to specialised receptors (for example FGF receptors) on nearby cells. These receptors propagate the signal to the nucleus of the receiving cell, which in turn dictates to the cell how it should react. FGFR signalling is versatile, tightly controlled and important for normal body homeostasis, facilitating growth, healing and replacing old cells. However, cancer cells can take command of this pathway and use it to their advantage. This review will first explain the biology of FGFR signalling and then describe how it can be corrupted, the implications in cancer, and how it can be targeted to improve cancer therapy. Abstract The pleiotropic effects of fibroblast growth factors (FGFs), the widespread expression of all seven signalling FGF receptors (FGFRs) throughout the body, and the dramatic phenotypes shown by many FGF/R knockout mice, highlight the diversity, complexity and functional importance of FGFR signalling. The FGF/R axis is critical during normal tissue development, homeostasis and repair. Therefore, it is not surprising that substantial evidence also pinpoints the involvement of aberrant FGFR signalling in disease, including tumourigenesis. FGFR aberrations in cancer include mutations, gene fusions, and amplifications as well as corrupted autocrine/paracrine loops. Indeed, many clinical trials on cancer are focusing on targeting the FGF/FGFR axis, using selective FGFR inhibitors, nonselective FGFR tyrosine kinase inhibitors, ligand traps, and monoclonal antibodies and some have already been approved for the treatment of cancer patients. The heterogeneous tumour microenvironment and complexity of FGFR signalling may be some of the factors responsible for the resistance or poor response to therapy with FGFR axis-directed therapeutic agents. In the present review we will focus on the structure and function of FGF(R)s, their common irregularities in cancer and the therapeutic value of targeting their function in cancer.
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Abstract
Rnd proteins constitute a subfamily of Rho GTPases represented in mammals by Rnd1, Rnd2 and Rnd3. Despite their GTPase structure, their specific feature is the inability to hydrolyse GTP-bound nucleotide. This aspect makes them atypical among Rho GTPases. Rnds are regulated for their expression at the transcriptional or post-transcriptional levels and they are activated through post-translational modifications and interactions with other proteins. Rnd proteins are mainly involved in the regulation of the actin cytoskeleton and cell proliferation. Whereas Rnd3 is ubiquitously expressed, Rnd1 and 2 are tissue-specific. Increasing data has described their important role during development and diseases. Herein, we describe their involvement in physiological and pathological conditions with a focus on the neuronal and vascular systems, and summarize their implications in tumorigenesis.
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Affiliation(s)
- Sara Basbous
- INSERM, BaRITOn, U1053, F-33000, Univ. Bordeaux, Bordeaux, France
| | - Roberta Azzarelli
- Department of Biology, Unit of Cell and Developmental Biology, University of Pisa, Pisa, Italy
| | - Emilie Pacary
- INSERM, U1215 - Neurocentre Magendie, F-33077, Univ. Bordeaux, Bordeaux, France
| | - Violaine Moreau
- INSERM, BaRITOn, U1053, F-33000, Univ. Bordeaux, Bordeaux, France
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8
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Dunkel H, Chaverra M, Bradley R, Lefcort F. FGF
signaling is required for chemokinesis and ventral migration of trunk neural crest cells. Dev Dyn 2020; 249:1077-1097. [DOI: 10.1002/dvdy.190] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 04/24/2020] [Accepted: 05/04/2020] [Indexed: 11/08/2022] Open
Affiliation(s)
- Haley Dunkel
- Department of Cell Biology and NeuroscienceMontana State University Bozeman Montana USA
| | - Martha Chaverra
- Department of Cell Biology and NeuroscienceMontana State University Bozeman Montana USA
| | - Roger Bradley
- Department of Cell Biology and NeuroscienceMontana State University Bozeman Montana USA
| | - Frances Lefcort
- Department of Cell Biology and NeuroscienceMontana State University Bozeman Montana USA
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9
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Mouly L, Gilhodes J, Lemarié A, Cohen-Jonathan Moyal E, Toulas C, Favre G, Sordet O, Monferran S. The RND1 Small GTPase: Main Functions and Emerging Role in Oncogenesis. Int J Mol Sci 2019; 20:ijms20153612. [PMID: 31344837 PMCID: PMC6696182 DOI: 10.3390/ijms20153612] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 07/10/2019] [Accepted: 07/21/2019] [Indexed: 02/07/2023] Open
Abstract
The Rho GTPase family can be classified into classic and atypical members. Classic members cycle between an inactive Guanosine DiPhosphate -bound state and an active Guanosine TriPhosphate-bound state. Atypical Rho GTPases, such as RND1, are predominantly in an active GTP-bound conformation. The role of classic members in oncogenesis has been the subject of numerous studies, while that of atypical members has been less explored. Besides the roles of RND1 in healthy tissues, recent data suggest that RND1 is involved in oncogenesis and response to cancer therapeutics. Here, we present the current knowledge on RND1 expression, subcellular localization, and functions in healthy tissues. Then, we review data showing that RND1 expression is dysregulated in tumors, the molecular mechanisms involved in this deregulation, and the role of RND1 in oncogenesis. For several aggressive tumors, RND1 presents the features of a tumor suppressor gene. In these tumors, low expression of RND1 is associated with a bad prognosis for the patients. Finally, we highlight that RND1 expression is induced by anticancer agents and modulates their response. Of note, RND1 mRNA levels in tumors could be used as a predictive marker of both patient prognosis and response to anticancer agents.
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Affiliation(s)
- Laetitia Mouly
- Cancer Research Center of Toulouse, INSERM UMR1037, 31037 Toulouse, France
- Faculty of Pharmacy and Medecine, Université Toulouse III, 31062 Toulouse, France
| | - Julia Gilhodes
- Institut Claudius Regaud, IUCT-O, 31059 Toulouse, France
| | - Anthony Lemarié
- Cancer Research Center of Toulouse, INSERM UMR1037, 31037 Toulouse, France
- Faculty of Pharmacy and Medecine, Université Toulouse III, 31062 Toulouse, France
| | - Elizabeth Cohen-Jonathan Moyal
- Cancer Research Center of Toulouse, INSERM UMR1037, 31037 Toulouse, France
- Faculty of Pharmacy and Medecine, Université Toulouse III, 31062 Toulouse, France
- Institut Claudius Regaud, IUCT-O, 31059 Toulouse, France
| | - Christine Toulas
- Cancer Research Center of Toulouse, INSERM UMR1037, 31037 Toulouse, France
- Institut Claudius Regaud, IUCT-O, 31059 Toulouse, France
| | - Gilles Favre
- Cancer Research Center of Toulouse, INSERM UMR1037, 31037 Toulouse, France
- Faculty of Pharmacy and Medecine, Université Toulouse III, 31062 Toulouse, France
- Institut Claudius Regaud, IUCT-O, 31059 Toulouse, France
| | - Olivier Sordet
- Cancer Research Center of Toulouse, INSERM UMR1037, 31037 Toulouse, France
| | - Sylvie Monferran
- Cancer Research Center of Toulouse, INSERM UMR1037, 31037 Toulouse, France.
- Faculty of Pharmacy and Medecine, Université Toulouse III, 31062 Toulouse, France.
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10
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Vonk JM, Nieuwenhuis MAE, Dijk FN, Boudier A, Siroux V, Bouzigon E, Probst-Hensch N, Imboden M, Keidel D, Sin D, Bossé Y, Hao K, van den Berge M, Faiz A, Koppelman GH, Postma DS. Novel genes and insights in complete asthma remission: A genome-wide association study on clinical and complete asthma remission. Clin Exp Allergy 2018; 48:1286-1296. [PMID: 29786918 DOI: 10.1111/cea.13181] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 03/25/2018] [Accepted: 03/29/2018] [Indexed: 12/16/2022]
Abstract
BACKGROUND Asthma is a chronic respiratory disease without a cure, although there exists spontaneous remission. Genome-wide association (GWA) studies have pinpointed genes associated with asthma development, but did not investigate asthma remission. OBJECTIVE We performed a GWA study to develop insights in asthma remission. METHODS Clinical remission (ClinR) was defined by the absence of asthma treatment and wheezing in the last year and asthma attacks in the last 3 years and complete remission (ComR) similarly but additionally with normal lung function and absence of bronchial hyperresponsiveness (BHR). A GWA study on both ClinR and ComR was performed in 790 asthmatics with initial doctor diagnosis of asthma and BHR and long-term follow-up. We assessed replication of the 25 top single nucleotide polymorphisms (SNPs) in 2 independent cohorts (total n = 456), followed by expression quantitative loci (eQTL) analyses of the 4 replicated SNPs in lung tissue and epithelium. RESULTS Of the 790 asthmatics, 178 (23%) had ClinR and 55 ComR (7%) after median follow-up of 15.5 (range 3.3-47.8) years. In ClinR, 1 of the 25 SNPs, rs2740102, replicated in a meta-analysis of the replication cohorts, which was an eQTL for POLI in lung tissue. In ComR, 3 SNPs replicated in a meta-analysis of the replication cohorts. The top-hit, rs6581895, almost reached genome-wide significance (P-value 4.68 × 10-7 ) and was an eQTL for FRS2 and CCT in lung tissue. Rs1420101 was a cis-eQTL in lung tissue for IL1RL1 and IL18R1 and a trans-eQTL for IL13. CONCLUSIONS AND CLINICAL RELEVANCE By defining a strict remission phenotype, we identified 3 SNPs to be associated with complete asthma remission, where 2 SNPs have plausible biological relevance in FRS2, CCT, IL1RL1, IL18R1 and IL13.
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Affiliation(s)
- J M Vonk
- University of Groningen, University Medical Center Groningen, Department of Epidemiology, Groningen, The Netherlands.,University of Groningen, University Medical Center Groningen, Groningen Research Institute for Asthma and COPD (GRIAC), Groningen, The Netherlands
| | - M A E Nieuwenhuis
- University of Groningen, University Medical Center Groningen, Groningen Research Institute for Asthma and COPD (GRIAC), Groningen, The Netherlands.,University of Groningen, University Medical Center Groningen, Department of Pulmonology, Groningen, The Netherlands
| | - F N Dijk
- University of Groningen, University Medical Center Groningen, Groningen Research Institute for Asthma and COPD (GRIAC), Groningen, The Netherlands.,University of Groningen, University Medical Center Groningen, Department of Pediatric Pulmonology and Pediatric Allergology, Groningen, The Netherlands
| | - A Boudier
- INSERM, Team of Environmental Epidemiology applied to Reproduction and Respiratory Health, IAB, Grenoble, France
| | - V Siroux
- INSERM, Team of Environmental Epidemiology applied to Reproduction and Respiratory Health, IAB, Grenoble, France.,Team of Environmental Epidemiology applied to Reproduction and Respiratory Health, IAB, Univ. Grenoble Alpes, Grenoble, France.,CHU de Grenoble, Team of Environmental Epidemiology applied to Reproduction and Respiratory Health, IAB, Grenoble, France
| | - E Bouzigon
- UMR-946, Inserm, Paris, France.,Sorbonne Paris Cité, Institut Universitaire d'Hématologie, Université Paris Diderot, Paris, France
| | - N Probst-Hensch
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - M Imboden
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - D Keidel
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - D Sin
- St Paul's Hospital, The University of British Columbia James Hogg Research Laboratory, Vancouver, BC, Canada.,Respiratory Division, Department of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Y Bossé
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Department of Molecular Medicine, Laval University, Québec, QC, Canada
| | - K Hao
- Merck Research Laboratories, Boston, MA, USA
| | - M van den Berge
- University of Groningen, University Medical Center Groningen, Groningen Research Institute for Asthma and COPD (GRIAC), Groningen, The Netherlands.,University of Groningen, University Medical Center Groningen, Department of Pulmonology, Groningen, The Netherlands
| | - A Faiz
- University of Groningen, University Medical Center Groningen, Groningen Research Institute for Asthma and COPD (GRIAC), Groningen, The Netherlands.,University of Groningen, University Medical Center Groningen, Department of Pulmonology, Groningen, The Netherlands
| | - G H Koppelman
- University of Groningen, University Medical Center Groningen, Groningen Research Institute for Asthma and COPD (GRIAC), Groningen, The Netherlands.,University of Groningen, University Medical Center Groningen, Department of Pediatric Pulmonology and Pediatric Allergology, Groningen, The Netherlands
| | - D S Postma
- University of Groningen, University Medical Center Groningen, Groningen Research Institute for Asthma and COPD (GRIAC), Groningen, The Netherlands.,University of Groningen, University Medical Center Groningen, Department of Pulmonology, Groningen, The Netherlands
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11
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Xia B, Zou Y, Xu Z, Lv Y. Gene expression profiling analysis of the effects of low-intensity pulsed ultrasound on induced pluripotent stem cell-derived neural crest stem cells. Biotechnol Appl Biochem 2017; 64:927-937. [PMID: 28127791 DOI: 10.1002/bab.1554] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 01/21/2017] [Indexed: 12/22/2022]
Abstract
Low-intensity pulsed ultrasound (LIPUS) is a noninvasive technique that has been shown to affect cell proliferation, migration, and differentiation and promote the regeneration of damaged peripheral nerve. Our previous studies had proved that LIPUS can significantly promote the neural differentiation of induced pluripotent stem cell-derived neural crest stem cells (iPSCs-NCSCs) and enhance the repair of rat-transected sciatic nerve. To further explore the underlying mechanisms of LIPUS treatment of iPSCs-NCSCs, this study reported the gene expression profiling analysis of iPSCs-NCSCs before and after LIPUS treatment using the RNA-sequencing (RNA-Seq) method. It was found that expression of 76 genes of iPSCs-NCSCs cultured in a serum-free neural induction medium and expression of 21 genes of iPSCs-NCSCs cultured in a neuronal differentiation medium were significantly changed by LIPUS treatment. The differentially expressed genes are related to angiogenesis, nervous system activity and functions, cell activities, and so on. The RNA-seq results were further verified by a quantitative real-time reverse transcriptase polymerase chain reaction (qRT-PCR). High correlation was observed between the results obtained from qRT-PCR and RNA-Seq. This study presented new information on the global gene expression patterns of iPSCs-NCSCs after LIPUS treatment and may expand the understanding of the complex molecular mechanism of LIPUS treatment of iPSCs-NCSCs.
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Affiliation(s)
- Bin Xia
- Key Laboratory of Biorheological Science and Technology (Chongqing University), Ministry of Education, Bioengineering College, Chongqing University, Chongqing, People's Republic of China.,Mechanobiology and Regenerative Medicine Laboratory, Bioengineering College, Chongqing University, Chongqing, People's Republic of China
| | - Yang Zou
- Key Laboratory of Biorheological Science and Technology (Chongqing University), Ministry of Education, Bioengineering College, Chongqing University, Chongqing, People's Republic of China.,Mechanobiology and Regenerative Medicine Laboratory, Bioengineering College, Chongqing University, Chongqing, People's Republic of China
| | - Zhiling Xu
- Key Laboratory of Biorheological Science and Technology (Chongqing University), Ministry of Education, Bioengineering College, Chongqing University, Chongqing, People's Republic of China.,Mechanobiology and Regenerative Medicine Laboratory, Bioengineering College, Chongqing University, Chongqing, People's Republic of China
| | - Yonggang Lv
- Key Laboratory of Biorheological Science and Technology (Chongqing University), Ministry of Education, Bioengineering College, Chongqing University, Chongqing, People's Republic of China.,Mechanobiology and Regenerative Medicine Laboratory, Bioengineering College, Chongqing University, Chongqing, People's Republic of China
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12
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Tian X, Yan H, Li J, Wu S, Wang J, Fan L. Neurotrophin Promotes Neurite Outgrowth by Inhibiting Rif GTPase Activation Downstream of MAPKs and PI3K Signaling. Int J Mol Sci 2017; 18:E148. [PMID: 28098758 PMCID: PMC5297781 DOI: 10.3390/ijms18010148] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Revised: 01/01/2017] [Accepted: 01/06/2017] [Indexed: 12/16/2022] Open
Abstract
Members of the well-known semaphorin family of proteins can induce both repulsive and attractive signaling in neural network formation and their cytoskeletal effects are mediated in part by small guanosine 5'-triphosphatase (GTPases). The aim of this study was to investigate the cellular role of Rif GTPase in the neurotrophin-induced neurite outgrowth. By using PC12 cells which are known to cease dividing and begin to show neurite outgrowth responding to nerve growth factor (NGF), we found that semaphorin 6A was as effective as nerve growth factor at stimulating neurite outgrowth in PC12 cells, and that its neurotrophic effect was transmitted through signaling by mitogen-activated protein kinases (MAPKs) and phosphatidylinositol-3-kinase (PI3K). We further found that neurotrophin-induced neurite formation in PC12 cells could be partially mediated by inhibition of Rif GTPase activity downstream of MAPKs and PI3K signaling. In conclusion, we newly identified Rif as a regulator of the cytoskeletal rearrangement mediated by semaphorins.
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Affiliation(s)
- Xiaoxia Tian
- School of Life Sciences, Inner Mongolia University, Hohhot 010021, China.
| | - Huijuan Yan
- School of Life Sciences, Inner Mongolia University, Hohhot 010021, China.
| | - Jiayi Li
- School of Life Sciences, Inner Mongolia University, Hohhot 010021, China.
| | - Shuang Wu
- School of Life Sciences, Inner Mongolia University, Hohhot 010021, China.
| | - Junyu Wang
- School of Life Sciences, Inner Mongolia University, Hohhot 010021, China.
| | - Lifei Fan
- School of Life Sciences, Inner Mongolia University, Hohhot 010021, China.
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13
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Azzarelli R, Guillemot F, Pacary E. Function and regulation of Rnd proteins in cortical projection neuron migration. Front Neurosci 2015; 9:19. [PMID: 25705175 PMCID: PMC4319381 DOI: 10.3389/fnins.2015.00019] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 01/13/2015] [Indexed: 01/08/2023] Open
Abstract
The mammalian cerebral cortex contains a high variety of neuronal subtypes that acquire precise spatial locations and form long or short-range connections to establish functional neuronal circuits. During embryonic development, cortical projection neurons are generated in the areas lining the lateral ventricles and they subsequently undergo radial migration to reach the position of their final maturation within the cortical plate. The control of the neuroblast migratory behavior and the coordination of the migration process with other neurogenic events such as cell cycle exit, differentiation and final maturation are crucial to normal brain development. Among the key regulators of cortical neuron migration, the small GTP binding proteins of the Rho family and the atypical Rnd members play important roles in integrating intracellular signaling pathways into changes in cytoskeletal dynamics and motility behavior. Here we review the role of Rnd proteins during cortical neuronal migration and we discuss both the upstream mechanisms that regulate Rnd protein activity and the downstream molecular pathways that mediate Rnd effects on cell cytoskeleton.
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Affiliation(s)
- Roberta Azzarelli
- Cambridge Department of Oncology, Hutchison/MRC Research Centre, University of Cambridge Cambridge, UK
| | - François Guillemot
- Division of Molecular Neurobiology, MRC National Institute for Medical Research London, UK
| | - Emilie Pacary
- Institut National de la Santé et de la Recherche Médicale U862, Neurocentre Magendie Bordeaux, France ; Université de Bordeaux Bordeaux, France
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14
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Shen L, Qin K, Wang D, Zhang Y, Bai N, Yang S, Luo Y, Xiang R, Tan X. Overexpression of Oct4 suppresses the metastatic potential of breast cancer cells via Rnd1 downregulation. Biochim Biophys Acta Mol Basis Dis 2014; 1842:2087-95. [PMID: 25068817 DOI: 10.1016/j.bbadis.2014.07.015] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Revised: 07/07/2014] [Accepted: 07/21/2014] [Indexed: 02/05/2023]
Abstract
Although Oct4 is known as a critical transcription factor involved in maintaining "stemness", its role in tumor metastasis is still controversial. Herein, we overexpressed and silenced Oct4 expression in two breast cancer cell lines, MDA-MB-231 and 4T1, separately. Our data showed that ectopic overexpression of Oct4 suppressed cell migration and invasion in vitro and the formation of metastatic lung nodules in vivo. Conversely, Oct4 downregulation increased the metastatic potential of breast cancer cells both in vitro and in vivo. Furthermore, we identified Rnd1 as the downstream target of Oct4 by ribonucleic acid sequencing (RNA-seq) analysis, which was significantly downregulated upon Oct4 overexpression. Chromatin immunoprecipitation assays revealed the binding of Oct4 to the promoter region of Rnd1 by ectopic overexpression of Oct4. Dual luciferase assays indicated that Oct4 overexpression suppressed transcriptional activity of the Rnd1 promoter. Moreover, overexpression of Rnd1 partially rescued the inhibitory effects of Oct4 on the migration and invasion of breast cancer cells. Overexpression of Rnd1 counteracted the influence of Oct4 on the formation of cell adhesion and lamellipodia, which implied a potential underlying mechanism involving Rnd1. In addition, we also found that overexpression of Oct4 led to an elevation of E-cadherin expression, even in 4T1 cells that possess a relatively high basal level of E-cadherin. Rnd1 overexpression impaired the promoting effects of Oct4 on E-cadherin expression in MDA-MB-231 cells. These results suggest that Oct4 affects the metastatic potential of breast cancer cells through Rnd1-mediated effects that influence cell motility and E-cadherin expression.
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Affiliation(s)
- Long Shen
- Department of Pathology, Medical School of Nankai University, Tianjin 300071, China
| | - Kunhua Qin
- Department of Immunology, Medical School of Nankai University, Tianjin 300071, China
| | - Dekun Wang
- Department of Pathology, Medical School of Nankai University, Tianjin 300071, China
| | - Yan Zhang
- Department of Immunology, Medical School of Nankai University, Tianjin 300071, China
| | - Nan Bai
- Department of Immunology, Medical School of Nankai University, Tianjin 300071, China
| | - Shengyong Yang
- West China Hospital, Molecular Medicine Research Centre, State Key Lab Biotherapy, Sichuan University, Chengdu 610064, China
| | - Yunping Luo
- Department of Immunology, Beijing Union Medical School, Beijing 100010, China
| | - Rong Xiang
- Department of Immunology, Medical School of Nankai University, Tianjin 300071, China
| | - Xiaoyue Tan
- Department of Pathology, Medical School of Nankai University, Tianjin 300071, China.
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15
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Tiong KH, Mah LY, Leong CO. Functional roles of fibroblast growth factor receptors (FGFRs) signaling in human cancers. Apoptosis 2014; 18:1447-68. [PMID: 23900974 PMCID: PMC3825415 DOI: 10.1007/s10495-013-0886-7] [Citation(s) in RCA: 112] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The fibroblast growth factor receptors (FGFRs) regulate important biological processes including cell proliferation and differentiation during development and tissue repair. Over the past decades, numerous pathological conditions and developmental syndromes have emerged as a consequence of deregulation in the FGFRs signaling network. This review aims to provide an overview of FGFR family, their complex signaling pathways in tumorigenesis, and the current development and application of therapeutics targeting the FGFRs signaling for treatment of refractory human cancers.
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Affiliation(s)
- Kai Hung Tiong
- School of Postgraduate Studies and Research, International Medical University, Bukit Jalil, 57000, Kuala Lumpur, Malaysia,
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16
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SH2B1β interacts with STAT3 and enhances fibroblast growth factor 1-induced gene expression during neuronal differentiation. Mol Cell Biol 2014; 34:1003-19. [PMID: 24396070 DOI: 10.1128/mcb.00940-13] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Neurite outgrowth is an essential process during neuronal differentiation as well as neuroregeneration. Thus, understanding the molecular and cellular control of neurite outgrowth will benefit patients with neurological diseases. We have previously shown that overexpression of the signaling adaptor protein SH2B1β promotes fibroblast growth factor 1 (FGF1)-induced neurite outgrowth (W. F. Lin, C. J. Chen, Y. J. Chang, S. L. Chen, I. M. Chiu, and L. Chen, Cell. Signal. 21:1060-1072, 2009). SH2B1β also undergoes nucleocytoplasmic shuttling and regulates a subset of neurotrophin-induced genes. Although these findings suggest that SH2B1β regulates gene expression, the nuclear role of SH2B1β was not known. In this study, we show that SH2B1β interacts with the transcription factor, signal transducer, and activator of transcription 3 (STAT3) in neuronal PC12 cells, cortical neurons, and COS7 fibroblasts. By affecting the subcellular distribution of STAT3, SH2B1β increased serine phosphorylation and the concomitant transcriptional activity of STAT3. As a result, overexpressing SH2B1β enhanced FGF1-induced expression of STAT3 target genes Egr1 and Cdh2. Chromatin immunoprecipitation assays further reveal that, in response to FGF1, overexpression of SH2B1β promotes the in vivo occupancy of STAT3-Sp1 heterodimers at the promoter of Egr1 and Cdh2. These findings establish a central role of SH2B1β in orchestrating signaling events to transcriptional activation through interacting and regulating STAT3-containing complexes during neuronal differentiation.
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17
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Cao S, Mao X, Liu D, Buck M. Backbone assignment and secondary structure of Rnd1, an unusual Rho family small GTPase. BIOMOLECULAR NMR ASSIGNMENTS 2013; 7:121-128. [PMID: 22618864 DOI: 10.1007/s12104-012-9391-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Accepted: 05/03/2012] [Indexed: 06/01/2023]
Abstract
Rho GTPases have attracted considerable interest as signaling molecules due to their variety of functional roles in cells. Rnd1 is a relatively recently discovered Rho GTPase with no enzymatic activity against its bound GTP nucleotide, setting it apart from other family members. Research has revealed a critical role for Rnd1 not only in neurite outgrowth, dendrite development, axon guidance, but also in gastric cancer and in endothelial cells during inflammation. Structural information is crucial for understanding the mechanism that forms the basis for protein-protein interactions and functions, but until recently there were no reports of NMR studies directly on the Rnd1 protein. In this paper we report assignments for the majority of Rnd1 NMR resonances based on 2D and 3D NMR spectra. Rnd1 assignment was a challenging task, however, despite optimization strategies that have facilitated NMR studies of the protein (Cao and Buck in Small GTPase 2:295-304, 2012). Besides common triple-resonance experiments, 3D HNCA, 3D HN(CO)CA, 3D HNCO which are usually employed for sequence assignment, 3D NOESY experiments and specific labeling of 13 kinds of amino acids were also utilized to gain as many (1)H(N), (13)C, and (15)N resonances assignments as possible. For 170 cross peaks observed out of 183 possible mainchain N-H correlations in the (1)H-(15)N TROSY spectrum, backbone assignment was finally completed for 127 resonances. The secondary structure was then defined by chemical shifts and TALOS+ based on the assignments. The overall structure in solution compares well with that of Rnd1 in a crystal, except for two short segments, residues 77-83 and residues 127-131. Given that some features are shared among Rho GTPases, Rnd1 assignments are also compared with two other family members, Cdc42 and Rac1. The overall level of Rnd1 assignment is lower than for Cdc42 and Rac1, consistent with its lower stability and possibly increased internal dynamics. However, while the Rnd1 switch II region remained un-assigned, the switch I region could be more fully assigned compared to Cdc42 and Rac1. The NMR assignment and structure analysis reported here provides a robust basis for future study of the binding between Rnd1 and other proteins, as well as for further studies of the molecular function of this unusual GTPase.
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Affiliation(s)
- Shufen Cao
- College of Life Science, Central China Normal University, 152 Luoyu Road, Wuhan 430079, Hubei, China.
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18
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Hota PK, Buck M. Plexin structures are coming: opportunities for multilevel investigations of semaphorin guidance receptors, their cell signaling mechanisms, and functions. Cell Mol Life Sci 2012; 69:3765-805. [PMID: 22744749 PMCID: PMC11115013 DOI: 10.1007/s00018-012-1019-0] [Citation(s) in RCA: 125] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2012] [Revised: 04/09/2012] [Accepted: 04/11/2012] [Indexed: 01/13/2023]
Abstract
Plexin transmembrane receptors and their semaphorin ligands, as well as their co-receptors (Neuropilin, Integrin, VEGFR2, ErbB2, and Met kinase) are emerging as key regulatory proteins in a wide variety of developmental, regenerative, but also pathological processes. The diverse arenas of plexin function are surveyed, including roles in the nervous, cardiovascular, bone and skeletal, and immune systems. Such different settings require considerable specificity among the plexin and semaphorin family members which in turn are accompanied by a variety of cell signaling networks. Underlying the latter are the mechanistic details of the interactions and catalytic events at the molecular level. Very recently, dramatic progress has been made in solving the structures of plexins and of their complexes with associated proteins. This molecular level information is now suggesting detailed mechanisms for the function of both the extracellular as well as the intracellular plexin regions. Specifically, several groups have solved structures for extracellular domains for plexin-A2, -B1, and -C1, many in complex with semaphorin ligands. On the intracellular side, the role of small Rho GTPases has been of particular interest. These directly associate with plexin and stimulate a GTPase activating (GAP) function in the plexin catalytic domain to downregulate Ras GTPases. Structures for the Rho GTPase binding domains have been presented for several plexins, some with Rnd1 bound. The entire intracellular domain structure of plexin-A1, -A3, and -B1 have also been solved alone and in complex with Rac1. However, key aspects of the interplay between GTPases and plexins remain far from clear. The structural information is helping the plexin field to focus on key questions at the protein structural, cellular, as well as organism level that collaboratoria of investigations are likely to answer.
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Affiliation(s)
- Prasanta K. Hota
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, 10900 Euclid Ave., Cleveland, OH 44106 USA
| | - Matthias Buck
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, 10900 Euclid Ave., Cleveland, OH 44106 USA
- Department of Neuroscience, Case Western Reserve University School of Medicine, 10900 Euclid Ave., Cleveland, OH 44106 USA
- Department of Pharmacology, Case Western Reserve University School of Medicine, 10900 Euclid Ave., Cleveland, OH 44106 USA
- Comprehensive Cancer Center, Case Western Reserve University School of Medicine, 10900 Euclid Ave., Cleveland, OH 44106 USA
- Center for Proteomics and Bioinformatics, Case Western Reserve University School of Medicine, 10900 Euclid Ave., Cleveland, OH 44106 USA
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19
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Auer M, Schweigreiter R, Hausott B, Thongrong S, Höltje M, Just I, Bandtlow C, Klimaschewski L. Rho-independent stimulation of axon outgrowth and activation of the ERK and Akt signaling pathways by C3 transferase in sensory neurons. Front Cell Neurosci 2012; 6:43. [PMID: 23087613 PMCID: PMC3468917 DOI: 10.3389/fncel.2012.00043] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2012] [Accepted: 09/23/2012] [Indexed: 11/15/2022] Open
Abstract
Peripheral nerve injury triggers the activation of RhoA in spinal motor and peripheral sensory neurons. RhoA activates a number of effector proteins including the Rho-associated kinase, ROCK, which targets the cytoskeleton and leads to inhibition of neurite outgrowth. Blockade of the Rho/ROCK pathway by pharmacological means improves axon regeneration after experimental injury. C3bot transferase, an exoenzyme produced by Clostridium botulinum, inactivates RhoA by ADP-ribosylation. It has been successfully applied in experimental CNS lesions to facilitate axon regeneration. Up to now it was not investigated thoroughly whether C3bot exerts positive effects on peripheral axon regeneration as well. In the present study, recombinant membrane permeable C3bot produced a small, but significant, axon outgrowth effect on peripheral sensory neurons dissociated from adult dorsal root ganglia (DRG) of the rat. Neuronal overexpression of C3, however, did not enhance axonal growth. Moreover, transfection of plasmids encoding dominant negative RhoA or RhoA specific shRNAs failed to increase axonal growth. Furthermore, we show that the C3bot mutant, C3E174Q, which lacks RhoA inhibitory activity, still stimulates axonal growth. When analyzing possible signaling mechanisms we found that extracellular signal-regulated kinase (ERK) and Akt are activated by C3bot and ERK is induced by the C3E174Q mutant. Upregulation of kinase activities by C3bot occurs significantly faster than inactivation of RhoA indicating a RhoA-independent pathway of action by C3bot. The induction of ERK signaling by C3bot was detected in embryonic hippocampal neurons, too. Taken together, although RhoA plays a central role for inhibition of axon outgrowth by myelin-derived inhibitors, it does not interfere with axonal growth of sensory neurons on a permissive substrate in vitro. C3bot blocks neuronal RhoA activity, but its positive effects on axon elongation and branching appear to be mediated by Rho independent mechanisms involving activation of axon growth promoting ERK and Akt kinases.
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Affiliation(s)
- Maria Auer
- Division of Neuroanatomy, Innsbruck Medical University Innsbruck, Austria
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20
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Tandon P, Conlon FL, Taylor JM. ROCKs cause SHP-wrecks and broken hearts. Small GTPases 2012; 3:209-12. [PMID: 22858643 PMCID: PMC3520883 DOI: 10.4161/sgtp.20960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022] Open
Abstract
During embryogenesis, the heart is one of the first organs to develop. Its formation requires a complex combination of migration of cardiac precursors to the ventral midline coupled with the fusion of these cardiogenic fields and subsequent cellular reorganization to form a linear heart tube. A finely controlled choreography of cell proliferation, adhesion, contraction and movement drives the heart tube to loop and subsequently septate to form the four-chambered mammalian heart we are familiar with. Defining how this plethora of cellular processes is controlled both spatially and temporally is a scientific feat that has fascinated researchers for decades. Unfortunately, the complex nature of this organ’s development also makes it a prime target for mutation-induced malformation, as evidenced by the multitude of prevalent congenital heart disorders identified that afflict up to 1% of the population.
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Affiliation(s)
- Panna Tandon
- Department of Genetics, University of North Carolina, Chapel Hill, NC, USA
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21
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Montani L, Bausch-Fluck D, Domingues AF, Wollscheid B, Relvas JB. Identification of new interacting partners for atypical Rho GTPases: a SILAC-based approach. Methods Mol Biol 2012; 827:305-317. [PMID: 22144283 DOI: 10.1007/978-1-61779-442-1_20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
In contrast to typical Rho GTPases the regulation of atypical Rho GTPases, such as the members of the RhoBTB subfamily, rarely depends on GEFs and/or GAPs. Instead, they are regulated at the level of their expression, by post-translational modifications, by their rate of degradation as well as through binding of diverse cell-specific interactors. Stable Isotope Labeling by Amino acids in Cell culture (SILAC) is a powerful cutting-edge mass-spectrometry-based technology allowing for protein-interaction studies in vitro with removal of false-positive identifications. In this chapter, we describe how the SILAC technology can be applied to the identification of new interacting partners for atypical - constitutively active - Rho GTPases, i.e. RhoBTB3.
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Affiliation(s)
- Laura Montani
- Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
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22
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Guillemot F, Zimmer C. From cradle to grave: the multiple roles of fibroblast growth factors in neural development. Neuron 2011; 71:574-88. [PMID: 21867876 DOI: 10.1016/j.neuron.2011.08.002] [Citation(s) in RCA: 150] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/04/2011] [Indexed: 01/08/2023]
Abstract
The generation of a functional nervous system involves a multitude of steps that are controlled by just a few families of extracellular signaling molecules. Among these, the fibroblast growth factor (FGF) family is particularly prominent for the remarkable diversity of its functions. FGFs are best known for their roles in the early steps of patterning of the neural primordium and proliferation of neural progenitors. However, other equally important functions have emerged more recently, including in the later steps of neuronal migration, axon navigation, and synaptogenesis. We review here these diverse functions and discuss the mechanisms that account for this unusual range of activities. FGFs are essential components of most protocols devised to generate therapeutically important neuronal populations in vitro or to stimulate neuronal repair in vivo. How FGFs promote the development of the nervous system and maintain its integrity will thus remain an important focus of research in the future.
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Affiliation(s)
- François Guillemot
- Division of Molecular Neurobiology, Medical Research Council, National Institute for Medical Research, The Ridgeway, Mill Hill, London NW71AA, UK.
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23
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Lin X, Zhang Y, Liu L, McKeehan WL, Shen Y, Song S, Wang F. FRS2α is essential for the fibroblast growth factor to regulate the mTOR pathway and autophagy in mouse embryonic fibroblasts. Int J Biol Sci 2011; 7:1114-21. [PMID: 21927580 PMCID: PMC3174388 DOI: 10.7150/ijbs.7.1114] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2011] [Accepted: 05/22/2011] [Indexed: 12/14/2022] Open
Abstract
Although the fibroblast growth factor (FGF) signaling axis plays important roles in cell survival, proliferation, and differentiation, the molecular mechanism underlying how the FGF elicits these diverse regulatory signals is not well understood. By using the Frs2α null mouse embryonic fibroblast (MEF) in conjunction with inhibitors to multiple signaling pathways, here we report that the FGF signaling axis activates mTOR via the FGF receptor substrate 2α (FRS2α)-mediated PI3K/Akt pathway, and suppresses autophagy activity in MEFs. In addition, the PI3K/Akt pathway regulated mTOR is crucial for the FGF signaling axis to suppress autophagy in MEFs. Since autophagy has been proposed to play important roles in cell survival, proliferation, and differentiation, the findings suggest a novel mechanism for the FGF signaling axis to transmit regulatory signals to downstream effectors.
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Affiliation(s)
- Xiang Lin
- Center for Cancer and Stem Cell Biology, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX 77030-3303, USA
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24
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Auer M, Hausott B, Klimaschewski L. Rho GTPases as regulators of morphological neuroplasticity. Ann Anat 2011; 193:259-66. [PMID: 21459565 PMCID: PMC3143277 DOI: 10.1016/j.aanat.2011.02.015] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2011] [Accepted: 02/28/2011] [Indexed: 11/17/2022]
Abstract
GTPases function as intracellular, bimolecular switches by adopting different conformational states in response to binding GDP or GTP. Their activation is mediated through cell-surface receptors. Rho GTPases act on several downstream effectors involved in cellular morphogenesis, cell polarity, migration and cell division. In neurons, Rho GTPases regulate various features of dendritic and axonal outgrowth during development and regeneration mainly through their effects on the cytoskeleton. This review summarizes the main functions of Rho, Rac and Cdc42 GTPases as key regulators of morphological neuroplasticity under normal and pathological conditions.
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Affiliation(s)
- Maria Auer
- Division of Neuroanatomy, Medical University of Innsbruck, Muellerstrasse 59, Innsbruck, Austria
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25
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Abstract
Docking proteins comprise a distinct category of intracellular, noncatalytic signalling protein, that function downstream of a variety of receptor and receptor-associated tyrosine kinases and regulate diverse physiological and pathological processes. The growth factor receptor bound 2-associated binder/Daughter of Sevenless, insulin receptor substrate, fibroblast growth factor receptor substrate 2 and downstream of tyrosine kinases protein families fall into this category. This minireview focuses on the structure, function and regulation of these proteins.
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Affiliation(s)
- Tilman Brummer
- Centre for Biological Systems Analysis (ZBSA), Albert-Ludwigs-University of Freiburg, Freiburg, Germany
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26
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Riou P, Villalonga P, Ridley AJ. Rnd proteins: Multifunctional regulators of the cytoskeleton and cell cycle progression. Bioessays 2010; 32:986-92. [DOI: 10.1002/bies.201000060] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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27
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Jeon CY, Kim HJ, Lee JY, Kim JB, Kim SC, Park JB. p190RhoGAP and Rap-dependent RhoGAP (ARAP3) inactivate RhoA in response to nerve growth factor leading to neurite outgrowth from PC12 cells. Exp Mol Med 2010; 42:335-44. [PMID: 20200473 DOI: 10.3858/emm.2010.42.5.035] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Rat pheochromocytoma (PC12) cells have been used to investigate neurite outgrowth. Nerve growth factor (NGF) has been well known to induce neurite outgrowth from PC12 cells. RhoA belongs to Ras-related small GTP-binding proteins, which regulate a variety of cellular processes, including cell morphology alteration, actin dynamics, and cell migration. NGF suppressed GTP-RhoA levels after 12 h in PC12 cells and was consistently required for a long time to induce neurite outgrowth. Constitutively active (CA)-RhoA suppressed neurite outgrowth from PC12 cells in response to NGF, whereas dominant-negative (DN)-RhoA stimulated it, suggesting that RhoA inactivation is essential for neurite outgrowth. Here, we investigated the mechanism of RhoA inactivation. DN-p190RhoGAP abrogated neurite outgrowth, whereas wild-type (WT)-p190RhoGAP and WT-Src synergistically stimulated it along with accelerating RhoA inactivation, suggesting that p190RhoGAP, which can be activated by Src, is a major component in inhibiting RhoA in response to NGF in PC12 cells. Contrary to RhoA, Rap1 was activated by NGF, and DN-Rap1 suppressed neurite outgrowth, suggesting that Rap1 is also essential for neurite outgrowth. RhoA was co-immunoprecipitated with Rap1, suggesting that Rap1 interacts with RhoA. Furthermore, a DN-Rap-dependent RhoGAP (ARAP3) prevented RhoA inactivation, abolishing neurite formation from PC12 cells in response to NGF. These results suggest that NGF activates Rap1, which, in turn, up-regulates ARAP3 leading to RhoA inactivation and neurite outgrowth from PC12 cells. Taken together, p190RhoGAP and ARAP3 seem to be two main factors inhibiting RhoA activity during neurite outgrowth in PC12 cells in response to NGF.
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Affiliation(s)
- Chan Young Jeon
- Department of Biochemistry, Hallym University College of Medicine, Chuncheon 200-702, Korea
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28
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Jeon CY, Kim HJ, Morii H, Mori N, Settleman J, Lee JY, Kim J, Kim SC, Park JB. Neurite outgrowth from PC12 cells by basic fibroblast growth factor (bFGF) is mediated by RhoA inactivation through p190RhoGAP and ARAP3. J Cell Physiol 2010; 224:786-94. [DOI: 10.1002/jcp.22184] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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29
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Hryciw T, MacDonald JIS, Phillips R, Seah C, Pasternak S, Meakin SO. The fibroblast growth factor receptor substrate 3 adapter is a developmentally regulated microtubule-associated protein expressed in migrating and differentiated neurons. J Neurochem 2009; 112:924-39. [PMID: 19943849 DOI: 10.1111/j.1471-4159.2009.06503.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Fibroblast growth factor (FGF) mediated signaling is essential to many aspects of neural development. Activated FGF receptors signal primarily through the FGF receptor substrate (Frs) adapters, which include Frs2/Frs2alpha and Frs3/Frs2beta. While some studies suggest that Frs3 can compensate for the loss of Frs2 in transfected cells, the lack of an effective Frs3 specific antibody has prevented efforts to determine the role(s) of the endogenous protein. To this end, we have generated a Frs3 specific antibody and have characterized the pattern of Frs3 expression in the developing nervous system, its subcellular localization as well as its biochemical properties. We demonstrate that Frs3 is expressed at low levels in the ventricular zone of developing cortex, between E12 and E15, and it co-localizes with nestin and acetylated alpha-tubulin in radial processes in the ventricular/subventricular zones as well as with betaIII tubulin in differentiated cortical neurons. Subcellular fractionation studies demonstrate that endogenous Frs3 is both soluble and plasma membrane associated while Frs3 expressed in 293T cells associates exclusively with lipid rafts. Lastly, we demonstrate that neuronal Frs3 binds microtubules comparable to the microtubule-associated protein, MAP2, while Frs2 does not. Collectively, these data suggest that neuronal Frs3 functions as a novel microtubule binding protein and they provide the first biochemical evidence that neuronal Frs3 is functionally distinct from Frs2/Frs2alpha.
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Affiliation(s)
- Todd Hryciw
- Molecular Brain Research Group, Robarts Research Institute, London, Ontario, Canada
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30
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Lartey J, López Bernal A. RHO protein regulation of contraction in the human uterus. Reproduction 2009; 138:407-24. [DOI: 10.1530/rep-09-0160] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The state of contraction in smooth muscle cells of the human uterus is dependent on the interaction of activated forms of actin and myosin. Ras homology (RHO) proteins are small monomeric GTP-binding proteins that regulate actin polymerisation and myosin phosphorylation in smooth muscle cells. Their action is determined by their level of expression, GTP-bound state, intracellular localisation and phosphorylated status. Agonist activated RHO proteins bind to effector kinases such as RHO kinase (ROCK) and diaphanous proteins (DIAPH) to regulate smooth muscle contraction by two mechanisms: ROCK activates smooth muscle myosin either by direct phosphorylation at Ser19/Thr18 or through inhibition of myosin phosphatase which is a trimeric protein regulated by ROCK and by other protein kinases. Actin-polymerising proteins such as DIAPH homolog 1 increase filamentous actin assembly to enhance acto-myosin cross bridge formation and contraction. This review explores recent advances in RHO protein signalling in human myometrium and proposes areas of further research to investigate the involvement of these proteins in the regulation of uterine contractility in pregnancy and labour.
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31
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Sato T, Gotoh N. The FRS2 family of docking/scaffolding adaptor proteins as therapeutic targets of cancer treatment. Expert Opin Ther Targets 2009; 13:689-700. [PMID: 19456272 DOI: 10.1517/14728220902942330] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
BACKGROUND There are two members--FRS2alpha and FRS2beta--in the fibroblast growth factor receptor substrate 2 (FRS2) family of docking/scaffolding adaptor proteins. These proteins function downstream of certain kinds of receptor tyrosine kinases (RTKs) that are important for tumorigenesis. FRS2alpha acts as a control centre for fibroblast growth factor receptor signalling and encourages tumorigenesis, while FRS2beta regulates EGFR signalling negatively, and might have a tumour suppressive role. Therefore, both proteins could be good therapeutic targets for the treatment of cancer. OBJECTIVE To examine the physiological and pathological roles of FRS2, especially in cancer, and describe their potential value as therapeutic targets. METHODS A review of relevant literature. RESULTS/CONCLUSIONS Although it is still difficult to develop small compounds to modify functions of FRS2 adaptor proteins, such compounds may be useful as the next generation of molecular targeting drugs. Combination therapy with RTK-targeting drugs and FRS2-targeting drugs may be useful for cancer treatment in the near future.
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Affiliation(s)
- Takuya Sato
- The University of Tokyo, Institute of Medical Science, Division of Systems Biomedical Technology, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan.
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32
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FGF-receptor substrate 2 functions as a molecular sensor integrating external regulatory signals into the FGF pathway. Cell Res 2009; 19:1165-77. [PMID: 19652666 DOI: 10.1038/cr.2009.95] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Fibroblast growth factor (FGF) receptor substrate 2alpha (FRS2alpha) is the main mediator of signaling in the FGF pathway. Recent studies have shown that mitogen-activated protein kinase (MAPK) phosphorylates serine and threonine residues in FRS2, negatively affecting FGF-induced tyrosine phosphorylation (PY) of FRS2. Several kinds of stimuli can induce serine/threonine phosphorylation (PS/T) of FRS2, indicating that FRS2 may be useful for studying crosstalk between growth factor signaling pathways. Here, we report that FGF-induced PY of FRS2 can be attenuated by EGF co-stimulation in PC12 cells; this inhibitory effect could be completely reversed by U0126, an inhibitor of MEK. We further identified the ERK1/2-binding motif in FRS2 and generated FRS2-3KL, a mutant lacking MAPK binding and PT upon FGF and/or EGF stimulation. Unlike wild-type (WT) FRS2, FGF-induced PY of FRS2-3KL could not be inhibited by EGF co-stimulation, and FRS2-3KL-expressing PC12 cells exhibited more differentiating potential than FRS2-WT-expressing cells in response to FGF treatment. These results suggest that PS/T of FRS2 mediated by the FRS2-MAPK negative regulatory loop may function as a molecular switch integrating negative regulatory signals from other pathways into FGFR-generated signal transduction.
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Minegishi Y, Iwanari H, Mochizuki Y, Horii T, Hoshino T, Kodama T, Hamakubo T, Gotoh N. Prominent expression of FRS2β protein in neural cells and its association with intracellular vesicles. FEBS Lett 2009; 583:807-14. [DOI: 10.1016/j.febslet.2009.01.042] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2009] [Revised: 01/22/2009] [Accepted: 01/22/2009] [Indexed: 12/12/2022]
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Mori K, Amano M, Takefuji M, Kato K, Morita Y, Nishioka T, Matsuura Y, Murohara T, Kaibuchi K. Rho-kinase contributes to sustained RhoA activation through phosphorylation of p190A RhoGAP. J Biol Chem 2008; 284:5067-76. [PMID: 19103606 DOI: 10.1074/jbc.m806853200] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
RhoA is transiently activated by specific extracellular signals such as endothelin-1 (ET-1) in vascular smooth muscle cells. RhoGAP negatively regulates RhoA activity: thus, RhoA becomes the GDP-bound inactive form afterward. Sustained activation of RhoA is induced with high doses of the extracellular signals and is implicated in certain diseases such as vasospasms. However, it remains largely unknown how prolonged activation of RhoA is induced. Here we show that Rho-kinase, an effector of RhoA, phosphorylated p190A RhoGAP at Ser(1150) and attenuated p190A RhoGAP activity in COS7 cells. Binding of Rnd to p190A RhoGAP is thought to enhance its activation. Phosphorylation of p190A RhoGAP by Rho-kinase impaired Rnd binding. Stimulation of vascular smooth muscle cells with a high dose of ET-1 provoked sustained RhoA activation and p190A RhoGAP phosphorylation, both of which were prohibited by a Rho-kinase inhibitor. The phosphomimic mutation of p190A RhoGAP weakened Rnd binding and RhoGAP activities. Taken together, these results suggest that ET-1 induces Rho-kinase activation and subsequent phosphorylation of p190A RhoGAP, leading to prolonged RhoA activation.
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Affiliation(s)
- Kazutaka Mori
- Department of Cell Pharmacology, Graduate School of Medicine, Nagoya University, 65 Tsurumai, Showa-ku, Nagoya 466-8550, Japan
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Li YH, Ghavampur S, Bondallaz P, Will L, Grenningloh G, Pu Schel AW. Rnd1 regulates axon extension by enhancing the microtubule destabilizing activity of SCG10. J Biol Chem 2008; 284:363-371. [PMID: 18996843 DOI: 10.1074/jbc.m808126200] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The GTPase Rnd1 affects actin dynamics antagonistically to Rho and has been implicated in the regulation of neurite outgrowth, dendrite development, and axon guidance. Here we show that Rnd1 interacts with the microtubule regulator SCG10. This interaction requires a central domain of SCG10 comprising about 40 amino acids located within the N-terminal-half of a putative alpha-helical domain and is independent of phosphorylation at the four identified phosphorylation sites that regulate SCG10 activity. Rnd1 enhances the microtubule destabilizing activity of SCG10 and both proteins colocalize in neurons. Knockdown of Rnd1 or SCG10 by RNAi suppressed axon extension, indicating a critical role for both proteins during neuronal differentiation. Overexpression of Rnd1 in neurons induces the formation of multiple axons. The effect of Rnd1 on axon extension depends on SCG10. These results indicate that SCG10 acts as an effector downstream of Rnd1 to regulate axon extensions by modulating microtubule organization.
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Affiliation(s)
- Ying-Hua Li
- Abteilung Molekularbiologie, Institut fu¨r Allgemeine Zoologie und Genetik, Westfa¨lische Wilhelms-Universita¨t Mu¨nster, Schloßplatz 5, D-48149 Mu¨nster, Germany and the Center for Psychiatric Neuroscience, Department of Psychiatry-Centre Hospitalier Universitaire Vaudois, University of Lausanne, 1008 Prilly, Switzerland
| | - Sharang Ghavampur
- Abteilung Molekularbiologie, Institut fu¨r Allgemeine Zoologie und Genetik, Westfa¨lische Wilhelms-Universita¨t Mu¨nster, Schloßplatz 5, D-48149 Mu¨nster, Germany and the Center for Psychiatric Neuroscience, Department of Psychiatry-Centre Hospitalier Universitaire Vaudois, University of Lausanne, 1008 Prilly, Switzerland
| | - Percy Bondallaz
- Abteilung Molekularbiologie, Institut fu¨r Allgemeine Zoologie und Genetik, Westfa¨lische Wilhelms-Universita¨t Mu¨nster, Schloßplatz 5, D-48149 Mu¨nster, Germany and the Center for Psychiatric Neuroscience, Department of Psychiatry-Centre Hospitalier Universitaire Vaudois, University of Lausanne, 1008 Prilly, Switzerland
| | - Lena Will
- Abteilung Molekularbiologie, Institut fu¨r Allgemeine Zoologie und Genetik, Westfa¨lische Wilhelms-Universita¨t Mu¨nster, Schloßplatz 5, D-48149 Mu¨nster, Germany and the Center for Psychiatric Neuroscience, Department of Psychiatry-Centre Hospitalier Universitaire Vaudois, University of Lausanne, 1008 Prilly, Switzerland
| | - Gabriele Grenningloh
- Abteilung Molekularbiologie, Institut fu¨r Allgemeine Zoologie und Genetik, Westfa¨lische Wilhelms-Universita¨t Mu¨nster, Schloßplatz 5, D-48149 Mu¨nster, Germany and the Center for Psychiatric Neuroscience, Department of Psychiatry-Centre Hospitalier Universitaire Vaudois, University of Lausanne, 1008 Prilly, Switzerland
| | - Andreas W Pu Schel
- Abteilung Molekularbiologie, Institut fu¨r Allgemeine Zoologie und Genetik, Westfa¨lische Wilhelms-Universita¨t Mu¨nster, Schloßplatz 5, D-48149 Mu¨nster, Germany and the Center for Psychiatric Neuroscience, Department of Psychiatry-Centre Hospitalier Universitaire Vaudois, University of Lausanne, 1008 Prilly, Switzerland.
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Gotoh N. Regulation of growth factor signaling by FRS2 family docking/scaffold adaptor proteins. Cancer Sci 2008; 99:1319-25. [PMID: 18452557 PMCID: PMC11159094 DOI: 10.1111/j.1349-7006.2008.00840.x] [Citation(s) in RCA: 195] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2008] [Accepted: 03/27/2008] [Indexed: 12/26/2022] Open
Abstract
The FRS2 family of adaptor/scaffold proteins has two members, FRS2alpha and FRS2beta. Both proteins contain N-terminal myristylation sites for localization on the plasma membrane and a PTB domain for binding to limited species of receptor tyrosine kinases (RTKs), including the FGF receptor, the neurotophin receptor, RET, and ALK. Activation of these RTKs allows FRS2 proteins to become phosphorylated of tyrosine residues and then bind to Grb2 and Shp2, a SH2 domain-containing adaptor and a tyrosine phosphatase, respectively. Subsequently, Shp2 activates a Ras/ERK pathway and Grb2 activates a Ras/ERK, phosphatidyl inositol (PI)-3 kinase and ubiquitination/degradation pathways by binding to SOS, Gab1, and Cbl via the SH3 domains of Grb2. FRS2alpha acts as 'a conning center' in FGF signaling mainly because it induces sustained levels of activation of ERK via Shp2-binding sites and Grb2-binding sites, though the contribution of the former is greater. Indeed, FRS2alpha knockout mice and mice with mutated Shp2-binding sites exhibit a variety of phenotypes due to defects in FGF signaling in vivo. Although FRS2beta binds to the EGF receptor, it does not induce tyrosine phosphorylation on the receptor. Instead, it inhibits EGF signaling, resulting in inhibition of EGF-induced cell proliferation and cell transformation. Based on these findings, the involvement of FRS2 proteins in tumorigenesis should be studied extensively to be validated as candidate biomarkers for the effectiveness of treatments targeting RTKs such as the FGF receptor and EGF receptor.
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Affiliation(s)
- Noriko Gotoh
- Division of Systems Biomedical Technology, Institute of Medical Science, University of Tokyo.
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Kinoshita N, Sasai N, Misaki K, Yonemura S. Apical accumulation of Rho in the neural plate is important for neural plate cell shape change and neural tube formation. Mol Biol Cell 2008; 19:2289-99. [PMID: 18337466 PMCID: PMC2366863 DOI: 10.1091/mbc.e07-12-1286] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2007] [Revised: 02/19/2008] [Accepted: 02/29/2008] [Indexed: 11/11/2022] Open
Abstract
Although Rho-GTPases are well-known regulators of cytoskeletal reorganization, their in vivo distribution and physiological functions have remained elusive. In this study, we found marked apical accumulation of Rho in developing chick embryos undergoing folding of the neural plate during neural tube formation, with similar accumulation of activated myosin II. The timing of accumulation and biochemical activation of both Rho and myosin II was coincident with the dynamics of neural tube formation. Inhibition of Rho disrupted its apical accumulation and led to defects in neural tube formation, with abnormal morphology of the neural plate. Continuous activation of Rho also altered neural tube formation. These results indicate that correct spatiotemporal regulation of Rho is essential for neural tube morphogenesis. Furthermore, we found that a key morphogenetic signaling pathway, the Wnt/PCP pathway, was implicated in the apical accumulation of Rho and regulation of cell shape in the neural plate, suggesting that this signal may be the spatiotemporal regulator of Rho in neural tube formation.
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Affiliation(s)
| | - Noriaki Sasai
- Organogenesis and Neurogenesis Group, RIKEN Center for Developmental Biology, Kobe 650-0047, Japan
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38
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Zhang Y, McKeehan K, Lin Y, Zhang J, Wang F. Fibroblast growth factor receptor 1 (FGFR1) tyrosine phosphorylation regulates binding of FGFR substrate 2alpha (FRS2alpha) but not FRS2 to the receptor. Mol Endocrinol 2008; 22:167-75. [PMID: 17901128 PMCID: PMC2194630 DOI: 10.1210/me.2007-0140] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2007] [Accepted: 09/20/2007] [Indexed: 11/19/2022] Open
Abstract
Binding of the fibroblast growth factor (FGF) to the FGF receptor (FGFR) tyrosine kinase leads to receptor tyrosine autophosphorylation as well as phosphorylation of multiple downstream signaling molecules that are recruited to the receptor either by direct binding or through adaptor proteins. The FGFR substrate 2 (FRS2) family consists of two members, FRS2alpha and FRS2beta, and has been shown to recruit multiple signaling molecules, including Grb2 and Shp2, to FGFR1. To better understand how FRS2 interacted with FGFR1, in vivo binding assays with coexpressed FGFR1 and FRS2 recombinant proteins in mammalian cells were carried out. The results showed that the interaction of full-length FRS2alpha, but not FRS2beta, with FGFR1 was enhanced by activation of the receptor kinase. The truncated FRS2alpha mutant that was comprised only of the phosphotyrosine-binding domain (PTB) bound FGFR1 constitutively, suggesting that the C-terminal sequence downstream the PTB domain inhibited the PTB-FGFR1 binding. Inactivation of the FGFR1 kinase and substitutions of tyrosine phosphorylation sites of FGFR1, but not FRS2alpha, reduced binding of FGFR1 with FRS2alpha. The results suggest that although the tyrosine autophosphorylation sites of FGFR1 did not constitute the binding sites for FRS2alpha, phosphorylation of these residues was essential for optimal interaction with FRS2alpha. In addition, it was demonstrated that the Grb2-binding sites of FRS2alpha are essential for mediating signals of FGFR1 to activate the FiRE enhancer of the mouse syndecan 1 gene. The results, for the first time, demonstrate the specific signals mediated by the Grb2-binding sites and further our understanding of FGF signal transmission at the adaptor level.
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MESH Headings
- 3T3 Cells
- Adaptor Proteins, Signal Transducing/genetics
- Adaptor Proteins, Signal Transducing/metabolism
- Animals
- Blotting, Western
- Cell Line
- Cells, Cultured
- Embryonic Stem Cells/cytology
- Embryonic Stem Cells/metabolism
- Fibroblasts/cytology
- Fibroblasts/metabolism
- GRB2 Adaptor Protein/genetics
- GRB2 Adaptor Protein/metabolism
- Humans
- Membrane Proteins/genetics
- Membrane Proteins/metabolism
- Mice
- Mutation
- Phosphorylation
- Protein Binding
- Protein Tyrosine Phosphatase, Non-Receptor Type 11/genetics
- Protein Tyrosine Phosphatase, Non-Receptor Type 11/metabolism
- Receptor, Fibroblast Growth Factor, Type 1/genetics
- Receptor, Fibroblast Growth Factor, Type 1/metabolism
- Signal Transduction/genetics
- Signal Transduction/physiology
- Transfection
- Tyrosine/metabolism
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Affiliation(s)
- Yongyou Zhang
- Center for Cancer and Stem Cell Biology, Institute of Biosciences and Technology, Texas A&M Health Science Center, 2121 West Holcombe Boulevard, Houston, Texas 77030-3303.
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Ogata S, Morokuma J, Hayata T, Kolle G, Niehrs C, Ueno N, Cho KW. TGF-beta signaling-mediated morphogenesis: modulation of cell adhesion via cadherin endocytosis. Genes Dev 2007; 21:1817-31. [PMID: 17639085 PMCID: PMC1920175 DOI: 10.1101/gad.1541807] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The molecular mechanisms governing the cell behaviors underlying morphogenesis remain a major focus of research in both developmental biology and cancer biology. TGF-beta ligands control cell fate specification via Smad-mediated signaling. However, their ability to guide cellular morphogenesis in a variety of biological contexts is poorly understood. We report on the discovery of a novel TGF-beta signaling-mediated cellular morphogenesis occurring during vertebrate gastrulation. Activin/nodal members of the TGF-beta superfamily induce the expression of two genes regulating cell adhesion during gastrulation: Fibronectin Leucine-rich Repeat Transmembrane 3 (FLRT3), a type I transmembrane protein containing extracellular leucine-rich repeats, and the small GTPase Rnd1. FLRT3 and Rnd1 interact physically and modulate cell adhesion during embryogenesis by controlling cell surface levels of cadherin through a dynamin-dependent endocytosis pathway. Our model suggests that cell adhesion can be dynamically regulated by sequestering cadherin through internalization, and subsequent redeploying internalized cadherin to the cell surface as needed. As numerous studies have linked aberrant expression of small GTPases, adhesion molecules such as cadherins, and TGF-beta signaling to oncogenesis and metastasis, it is tempting to speculate that this FLRT3/Rnd1/cadherin pathway might also control cell behavior and morphogenesis in adult tissue homeostasis.
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Affiliation(s)
- Souichi Ogata
- Department of Developmental and Cell Biology, Developmental Biology Center, University of California at Irvine, Irvine, California 92697, USA
| | - Junji Morokuma
- Department of Developmental Biology, National Institute for Basic Biology, Okazaki, Aichi 444-8585, Japan
| | - Tadayoshi Hayata
- Department of Developmental and Cell Biology, Developmental Biology Center, University of California at Irvine, Irvine, California 92697, USA
| | - Gabriel Kolle
- Division of Molecular Embryology, German Cancer Research Center (DKFZ), Heidelberg 69120, Germany
| | - Christof Niehrs
- Division of Molecular Embryology, German Cancer Research Center (DKFZ), Heidelberg 69120, Germany
| | - Naoto Ueno
- Department of Developmental Biology, National Institute for Basic Biology, Okazaki, Aichi 444-8585, Japan
- E-MAIL ; FAX 0564-57-7571
| | - Ken W.Y. Cho
- Department of Developmental and Cell Biology, Developmental Biology Center, University of California at Irvine, Irvine, California 92697, USA
- Corresponding authors.E-MAIL
; FAX (949) 824-9395
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40
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Panasyuk G, Nemazanyy I, Filonenko V, Negrutskii B, El'skaya AV. A2 isoform of mammalian translation factor eEF1A displays increased tyrosine phosphorylation and ability to interact with different signalling molecules. Int J Biochem Cell Biol 2007; 40:63-71. [PMID: 17936057 PMCID: PMC2279807 DOI: 10.1016/j.biocel.2007.08.014] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2007] [Revised: 08/21/2007] [Accepted: 08/22/2007] [Indexed: 02/06/2023]
Abstract
The eEF1A1 and eEF1A2 isoforms of translation elongation factor 1A have 98% similarity and perform the same protein synthesis function catalyzing codon-dependent binding of aminoacyl-tRNA to 80S ribosome. However, the isoforms apparently play different non-canonical roles in apoptosis and cancer development which are awaiting further investigations. We hypothesize that the difference in non-translational functions could be caused, in particular, by differential ability of the isoforms to be involved in phosphotyrosine-mediated signalling. The ability of eEF1A1 and eEF1A2 to interact with SH2 and SH3 domains of different signalling molecules in vitro was compared. Indeed, contrary to eEF1A1, eEF1A2 was able to interact with SH2 domains of Grb2, RasGAP, Shc and C-terminal part of Shp2 as well as with SH3 domains of Crk, Fgr, Fyn and phospholipase C-gamma1. Interestingly, the interaction of both isoforms with Shp2 in vivo was found using stable cell lines expressing eEF1A1-His or eEF1A2-His. The formation of a complex between endogenous eEF1A and Shp2 was also shown. Importantly, a higher level of tyrosine phosphorylation of eEF1A2 as compared to eEF1A1 was demonstrated in several independent experiments and its importance for interaction of eEF1A2 with Shp2 in vitro was revealed. Thus, despite the fact that both isoforms of eEF1A could be involved in the phosphotyrosine-mediated processes, eEF1A2 apparently has greater potential to participate in such signalling pathways. Since tyrosine kinases/phosphatases play a prominent role in human cancerogenesis, our observations may gave a basis for recently found oncogenicity of the eEF1A2 isoform.
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Affiliation(s)
- Ganna Panasyuk
- Institute of Molecular Biology and Genetics, National Academy of Sciences of Ukraine, Kyiv, Ukraine
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41
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Obara Y, Hoshino T, Marcotullio MC, Pagiotti R, Nakahata N. A novel cyathane diterpene, cyrneine A, induces neurite outgrowth in a Rac1-dependent mechanism in PC12 cells. Life Sci 2007; 80:1669-77. [PMID: 17337280 DOI: 10.1016/j.lfs.2007.01.057] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2006] [Revised: 12/21/2006] [Accepted: 01/22/2007] [Indexed: 12/13/2022]
Abstract
We examined the effects of cyrneine A, a novel diterpene isolated from the mushroom Sarcodon cyrneus, on morphology of rat pheochromocytoma cells (PC12). In response to cyrneine A, PC12 cells extended their neurites, an effect partially blocked by the extracellular signal-regulated kinase (ERK) kinase inhibitor PD98059, but not by the protein kinase C inhibitor GF109203X, nor the phosphatidylinositol-3-kinase inhibitor wortmannin. Cyrneine A did not activate ERK at any of the time points tested (5-120 min), indicating that only the basal activity of ERK is required for cyrneine A-induced neurite outgrowth. As transcriptional regulation is required for neurite extension, the activity of three major transcription factors was determined. Cyrneine A enhanced activation of the transcription factors activator protein-1 (AP-1) and nuclear factor-kappaB, but not CREB, and this was accompanied by enhanced c-fos expression. Moreover, we determined the role of Rac1, a small GTPase protein of the Rho family that regulates actin dynamics, in cyrneine A-induced neurite outgrowth. Treatment with cyrneine A led to actin translocation and subsequently, to accumulation of F-actin at the tip of neurites. Rac1 activity was increased by cyrneine A and expression of a dominant-negative Rac1 mutant significantly inhibited the cyrneine A-induced extension of neurites. These results suggest that cyrneine A induces neurite outgrowth in a Rac1-dependent mechanism.
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Affiliation(s)
- Yutaro Obara
- Department of Cellular Signaling and 21st COE program CRESCENDO, Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba, Aramaki, Sendai, Miyagi, Japan.
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42
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Huang L, Watanabe M, Chikamori M, Kido Y, Yamamoto T, Shibuya M, Gotoh N, Tsuchida N. Unique role of SNT-2/FRS2β/FRS3 docking/adaptor protein for negative regulation in EGF receptor tyrosine kinase signaling pathways. Oncogene 2006; 25:6457-66. [PMID: 16702953 DOI: 10.1038/sj.onc.1209656] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The membrane-linked docking protein SNT-2/FRS2beta/FRS3 becomes tyrosine phosphorylated in response to fibroblast growth factors (FGFs) and neurotrophins and serves as a platform for recruitment of multiple signaling proteins, including Grb2 and Shp2, to FGF receptors or neurotrophin receptors. We previously reported that SNT-2 is not tyrosine phosphorylated significantly in response to epidermal growth factor (EGF) but that it inhibits ERK activation via EGF stimulation by forming a complex with ERK2. In the present report, we show that expression of SNT-2 suppressed EGF-induced cell transformation and proliferation, and expression level of SNT-2 is downregulated in cancer. The activities of the major signaling molecules in EGF receptor (EGFR) signal transduction pathways, including autophosphorylation of EGFR, were attenuated in cells expressing SNT-2 but not in cells expressing SNT-2 mutants lacking the ERK2-binding domain. Furthermore, SNT-2 constitutively bound to EGFR through the phosphotyrosine binding (PTB) domain both with and without EGF stimulation. Treatment of cells with MEK inhibitor U0126 partially restored the phosphorylation levels of MEK and EGFR in cells expressing SNT-2. On the basis of these findings, we propose a novel mechanism of negative control of EGFR tyrosine kinase activity with SNT-2 by recruiting ERK2, which is the site of negative-feedback loop from ERK, ultimately leading to inhibition of EGF-induced cell transformation and proliferation.
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Affiliation(s)
- L Huang
- Department of Molecular Cellular Oncology and Microbiology, Graduate School, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo, Japan
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Dixon SJ, MacDonald JIS, Robinson KN, Kubu CJ, Meakin SO. Trk receptor binding and neurotrophin/fibroblast growth factor (FGF)-dependent activation of the FGF receptor substrate (FRS)-3. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2006; 1763:366-80. [PMID: 16697063 DOI: 10.1016/j.bbamcr.2006.02.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2005] [Revised: 02/03/2006] [Accepted: 02/13/2006] [Indexed: 11/30/2022]
Abstract
We have investigated the signaling properties of the fibroblast growth factor (FGF) receptor substrate 3 (FRS3), also known as SNT-2 or FRS2beta, in neurotrophin-dependent differentiation in comparison with the related adapter FRS2 (SNT1 or FRS2alpha). We demonstrate that FRS3 binds all neurotrophin Trk receptor tyrosine kinases and becomes tyrosine phosphorylated in response to NGF, BDNF, NT-3 and FGF stimulation in transfected cells and/or primary cortical neurons. Second, the signaling molecules Grb2 and Shp2 bind FRS3 at consensus sites that are highly conserved among FRS family members and that Shp2, in turn, becomes tyrosine phosphorylated. While FRS3 over-expression in PC12 cells neither increases NGF-induced neuritogenesis nor activation of Map kinase/AKT, comparable to previous reports on FRS2, over-expression of a chimeric adapter containing the PH/PTB domains of the insulin receptor substrate (IRS) 2, in place of the PTB domain of FRS3 (IRS2-FRS3) supports insulin-dependent Map kinase activation and neurite outgrowth in PC12 cells. Collectively, these data demonstrate that FRS3 supports ligand-induced Map kinase activation and that the chimeric IRS2-FRS3 adapter is stimulating sufficient levels of activated MapK to support neurite outgrowth in PC12 cells.
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Affiliation(s)
- Scott J Dixon
- Laboratory of Neural Signaling, Cell Biology Group, The John P. Robarts Research Institute, London, Ontario, Canada N6A 5K8
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Abstract
The Rnd proteins, which form a distinct sub-group of the Rho family of small GTP-binding proteins, have been shown to regulate the organization of the actin cytoskeleton in several tissues. In the brain, they participate in neurite extension, whereas in smooth muscle, they modulate contractility. Recent evidence has shown that Rnd3 (RhoE) is also involved in the regulation of cell-cycle progression and transformation, indicating that these proteins might have other, as yet unexplored roles.
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Affiliation(s)
- Pierre Chardin
- Institut de Pharmacologie Moleculaire et Cellulaire, Centre National de la Recherche Scientifique, 660 Route des Lucioles, Sophia Antipolis, 06560 Valbonne, France.
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Ishikawa Y, Katoh H, Negishi M. Small GTPase Rnd1 is involved in neuronal activity-dependent dendritic development in hippocampal neurons. Neurosci Lett 2006; 400:218-23. [PMID: 16530331 DOI: 10.1016/j.neulet.2006.02.064] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2006] [Revised: 02/20/2006] [Accepted: 02/20/2006] [Indexed: 10/24/2022]
Abstract
Rho family small GTPases are key regulators for neuronal morphogenesis including dendritogenesis. We recently have shown that Rnd1, a member of the Rho family, is highly expressed in brain during the synaptogenic stage and is involved in dendritic spine formation. However, the mechanism by which Rnd1 regulates dendritic development including spine morphogenesis remains unknown. Here we report that Rnd1, a member of the Rho family, plays a critical role in neuronal activity-dependent dendritic development in hippocampal neurons. Overexpression of Rnd1 promoted dendritic growth and branching in cultured hippocampal neurons. On the other hand, suppression of endogenous Rnd1 expression by RNA interference significantly inhibited neuronal activity-dependent dendritic development and this inhibitory effect was canceled by inhibition of RhoA effector ROCK. In addition, knockdown of Rnd1 also abolished dendritic development promoted by treatment with brain-derived neurotrophic factor in hippocampal neurons. Our findings demonstrate that Rnd1 is involved in signaling pathways of neuronal activity-dependent dendritic development.
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Affiliation(s)
- Yukio Ishikawa
- Laboratory of Molecular Neurobiology, Graduate School of Biostudies, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
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Tanaka H, Katoh H, Negishi M. Pragmin, a novel effector of Rnd2 GTPase, stimulates RhoA activity. J Biol Chem 2006; 281:10355-64. [PMID: 16481321 DOI: 10.1074/jbc.m511314200] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The Rho family of small GTPases has been implicated in the reorganization of actin cytoskeleton and subsequent morphological changes in various cells. Rnd2 is a member of the Rnd subfamily, comprising Rnd1, Rnd2, and Rnd3. In contrast to Rnd1 and Rnd3, displaying an antagonistic action for RhoA signaling, signaling pathways of Rnd2 are not well known. Here we have performed a yeast two-hybrid screen using Rnd2 as bait and identified a novel Rnd2 effector protein, predominantly expressed in neurons, including cortical and hippocampal neurons. We named it Pragmin (pragma of Rnd2). In in vivo and in vitro binding assays, Pragmin specifically binds to Rnd2 among the Rho family GTPases in a GTP-dependent manner. Rnd2-bound Pragmin significantly stimulates RhoA activity and induces cell contraction through RhoA and the Rho-kinase pathway in HeLa cells. In PC12 cells, expressing Pragmin inhibits nerve growth factor-induced neurite outgrowth in response to Rnd2, and knock-down of Pragmin by Pragmin-specific small interfering RNA enhances neurite elongation. Therefore, Rnd2 regulates neurite outgrowth by functioning as the RhoA activator through Pragmin, in contrast to Rnd1 and Rnd3 inhibiting RhoA signaling.
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Affiliation(s)
- Hiroko Tanaka
- Laboratory of Molecular Neurobiology, Graduate School of Biostudies, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
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