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Brandão-Teles C, Antunes ASLM, de Moraes Vrechi TA, Martins-de-Souza D. The Roles of hnRNP Family in the Brain and Brain-Related Disorders. Mol Neurobiol 2024; 61:3578-3595. [PMID: 37999871 DOI: 10.1007/s12035-023-03747-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Accepted: 10/25/2023] [Indexed: 11/25/2023]
Abstract
Heterogeneous nuclear ribonucleoproteins (hnRNPs) belong to a complex family of RNA-binding proteins that are essential to control alternative splicing, mRNA trafficking, synaptic plasticity, stress granule formation, cell cycle regulation, and axonal transport. Over the past decade, hnRNPs have been associated with different brain disorders such as Alzheimer's disease, multiple sclerosis, and schizophrenia. Given their essential role in maintaining cell function and integrity, it is not surprising that dysregulated hnRNP levels lead to neurological implications. This review aims to explore the primary functions of hnRNPs in neurons, oligodendrocytes, microglia, and astrocytes, and their roles in brain disorders. We also discuss proteomics and other technologies and their potential for studying and evaluating hnRNPs in brain disorders, including the discovery of new therapeutic targets and possible pharmacological interventions.
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Affiliation(s)
- Caroline Brandão-Teles
- Laboratory of Neuroproteomics, Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas, Campinas, Brazil.
| | - André S L M Antunes
- Brazilian Biosciences National Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, Brazil
| | - Talita Aparecida de Moraes Vrechi
- Laboratory of Neuroproteomics, Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas, Campinas, Brazil
| | - Daniel Martins-de-Souza
- Laboratory of Neuroproteomics, Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas, Campinas, Brazil.
- D'Or Institute for Research and Education (IDOR), São Paulo, Brazil.
- Experimental Medicine Research Cluster (EMRC), University of Campinas, Campinas, SP, 13083-862, Brazil.
- INCT in Modelling Human Complex Diseases with 3D Platforms (Model3D), São Paulo, Brazil.
- Conselho Nacional de Desenvolvimento Científico e Tecnológico, Instituto Nacional de Biomarcadores em Neuropsiquiatria, São Paulo, Brazil.
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2
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Han KA, Ko J. Orchestration of synaptic functions by WAVE regulatory complex-mediated actin reorganization. Exp Mol Med 2023; 55:1065-1075. [PMID: 37258575 PMCID: PMC10318009 DOI: 10.1038/s12276-023-01004-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 03/13/2023] [Accepted: 03/13/2023] [Indexed: 06/02/2023] Open
Abstract
The WAVE regulatory complex (WRC), composed of five components-Cyfip1/Sra1, WAVE/Scar, Abi, Nap1/Nckap1, and Brk1/HSPC300-is essential for proper actin cytoskeletal dynamics and remodeling in eukaryotic cells, likely by matching various patterned signals to Arp2/3-mediated actin nucleation. Accumulating evidence from recent studies has revealed diverse functions of the WRC in neurons, demonstrating its crucial role in dictating the assembly of molecular complexes for the patterning of various trans-synaptic signals. In this review, we discuss recent exciting findings on the physiological role of the WRC in regulating synaptic properties and highlight the involvement of WRC dysfunction in various brain disorders.
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Affiliation(s)
- Kyung Ah Han
- Department of Brain Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), 333 Techno Jungangdae-Ro, Hyeonpoong-Eup, Dalseong-Gun, Daegu, 42988, Korea
- Center for Synapse Diversity and Specificity, DGIST, Daegu, 42988, Korea
| | - Jaewon Ko
- Department of Brain Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), 333 Techno Jungangdae-Ro, Hyeonpoong-Eup, Dalseong-Gun, Daegu, 42988, Korea.
- Center for Synapse Diversity and Specificity, DGIST, Daegu, 42988, Korea.
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3
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Costa RO, Martins LF, Tahiri E, Duarte CB. Brain-derived neurotrophic factor-induced regulation of RNA metabolism in neuronal development and synaptic plasticity. WILEY INTERDISCIPLINARY REVIEWS. RNA 2022; 13:e1713. [PMID: 35075821 DOI: 10.1002/wrna.1713] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 12/17/2021] [Accepted: 12/22/2021] [Indexed: 06/14/2023]
Abstract
The neurotrophin brain-derived neurotrophic factor (BDNF) plays multiple roles in the nervous system, including in neuronal development, in long-term synaptic potentiation in different brain regions, and in neuronal survival. Alterations in these regulatory mechanisms account for several diseases of the nervous system. The synaptic effects of BDNF mediated by activation of tropomyosin receptor kinase B (TrkB) receptors are partly mediated by stimulation of local protein synthesis which is now considered a ubiquitous feature in both presynaptic and postsynaptic compartments of the neuron. The capacity to locally synthesize proteins is of great relevance at several neuronal developmental stages, including during neurite development, synapse formation, and stabilization. The available evidence shows that the effects of BDNF-TrkB signaling on local protein synthesis regulate the structure and function of the developing and mature synapses. While a large number of studies have illustrated a wide range of effects of BDNF on the postsynaptic proteome, a growing number of studies also point to presynaptic effects of the neurotrophin in the local regulation of the protein composition at the presynaptic level. Here, we will review the latest evidence on the role of BDNF in local protein synthesis, comparing the effects on the presynaptic and postsynaptic compartments. Additionally, we overview the relevance of BDNF-associated local protein synthesis in neuronal development and synaptic plasticity, at the presynaptic and postsynaptic compartments, and their relevance in terms of disease. This article is categorized under: RNA Interactions with Proteins and Other Molecules > Protein-RNA Interactions: Functional Implications RNA Export and Localization > RNA Localization.
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Affiliation(s)
- Rui O Costa
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
- Institute for Interdisciplinary Research, University of Coimbra, Coimbra, Portugal
| | - Luís F Martins
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
- Institute for Interdisciplinary Research, University of Coimbra, Coimbra, Portugal
- Molecular Neurobiology Laboratory, Division of Neuroscience, San Raffaele Scientific Institute, Milan, Italy
| | - Emanuel Tahiri
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Carlos B Duarte
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
- Department of Life Sciences, University of Coimbra, Coimbra, Portugal
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4
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Colameo D, Rajman M, Soutschek M, Bicker S, von Ziegler L, Bohacek J, Winterer J, Germain PL, Dieterich C, Schratt G. Pervasive compartment-specific regulation of gene expression during homeostatic synaptic scaling. EMBO Rep 2021; 22:e52094. [PMID: 34396684 PMCID: PMC8490987 DOI: 10.15252/embr.202052094] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 07/12/2021] [Accepted: 07/20/2021] [Indexed: 12/13/2022] Open
Abstract
Synaptic scaling is a form of homeostatic plasticity which allows neurons to adjust their action potential firing rate in response to chronic alterations in neural activity. Synaptic scaling requires profound changes in gene expression, but the relative contribution of local and cell‐wide mechanisms is controversial. Here we perform a comprehensive multi‐omics characterization of the somatic and process compartments of primary rat hippocampal neurons during synaptic scaling. We uncover both highly compartment‐specific and correlating changes in the neuronal transcriptome and proteome. Whereas downregulation of crucial regulators of neuronal excitability occurs primarily in the somatic compartment, structural components of excitatory postsynapses are mostly downregulated in processes. Local inhibition of protein synthesis in processes during scaling is confirmed for candidate synaptic proteins. Motif analysis further suggests an important role for trans‐acting post‐transcriptional regulators, including RNA‐binding proteins and microRNAs, in the local regulation of the corresponding mRNAs. Altogether, our study indicates that, during synaptic scaling, compartmentalized gene expression changes might co‐exist with neuron‐wide mechanisms to allow synaptic computation and homeostasis.
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Affiliation(s)
- David Colameo
- Laboratory of Systems Neuroscience, Institute for Neuroscience, Department of Health Science and Technology, Swiss Federal Institute of Technology ETH, Zurich, Switzerland.,Neuroscience Center Zurich, ETH Zurich and University of Zurich, Zurich, Switzerland
| | - Marek Rajman
- Institute for Physiological Chemistry, Biochemical-Pharmacological Center Marburg, Philipps-University of Marburg, Marburg, Germany
| | - Michael Soutschek
- Laboratory of Systems Neuroscience, Institute for Neuroscience, Department of Health Science and Technology, Swiss Federal Institute of Technology ETH, Zurich, Switzerland.,Neuroscience Center Zurich, ETH Zurich and University of Zurich, Zurich, Switzerland
| | - Silvia Bicker
- Laboratory of Systems Neuroscience, Institute for Neuroscience, Department of Health Science and Technology, Swiss Federal Institute of Technology ETH, Zurich, Switzerland.,Neuroscience Center Zurich, ETH Zurich and University of Zurich, Zurich, Switzerland
| | - Lukas von Ziegler
- Neuroscience Center Zurich, ETH Zurich and University of Zurich, Zurich, Switzerland.,Laboratory of Behavioural and Molecular Neuroscience, Institute for Neuroscience, Department of Health Science and Technology, Swiss Federal Institute of Technology ETH, Zurich, Switzerland
| | - Johannes Bohacek
- Neuroscience Center Zurich, ETH Zurich and University of Zurich, Zurich, Switzerland.,Laboratory of Behavioural and Molecular Neuroscience, Institute for Neuroscience, Department of Health Science and Technology, Swiss Federal Institute of Technology ETH, Zurich, Switzerland
| | - Jochen Winterer
- Laboratory of Systems Neuroscience, Institute for Neuroscience, Department of Health Science and Technology, Swiss Federal Institute of Technology ETH, Zurich, Switzerland.,Neuroscience Center Zurich, ETH Zurich and University of Zurich, Zurich, Switzerland
| | - Pierre-Luc Germain
- Institute for Neuroscience, Department of Health Science and Technology, Swiss Federal Institute of Technology ETH, Zurich, Switzerland.,Laboratory of Statistical Bioinformatics, Department of Molecular Life Sciences, University of Zürich, Zurich, Switzerland
| | - Christoph Dieterich
- Section of Bioinformatics and Systems Cardiology, Department of Internal Medicine III and Klaus Tschira Institute for Integrative Computational Cardiology, University of Heidelberg, Heidelberg, Germany
| | - Gerhard Schratt
- Laboratory of Systems Neuroscience, Institute for Neuroscience, Department of Health Science and Technology, Swiss Federal Institute of Technology ETH, Zurich, Switzerland.,Neuroscience Center Zurich, ETH Zurich and University of Zurich, Zurich, Switzerland
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5
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Robinson H, Ruelcke JE, Lewis A, Bond CS, Fox AH, Bharti V, Wani S, Cloonan N, Lai A, Margolin D, Li L, Salomon C, Richards RS, Farrell A, Gardiner RA, Parton RG, Cristino AS, Hill MM. Caveolin-1-driven membrane remodelling regulates hnRNPK-mediated exosomal microRNA sorting in cancer. Clin Transl Med 2021; 11:e381. [PMID: 33931969 PMCID: PMC8031663 DOI: 10.1002/ctm2.381] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 03/15/2021] [Accepted: 03/17/2021] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Caveolae proteins play diverse roles in cancer development and progression. In prostate cancer, non-caveolar caveolin-1 (CAV1) promotes metastasis, while CAVIN1 attenuates CAV1-induced metastasis. Here, we unveil a novel mechanism linking CAV1 to selective loading of exosomes with metastasis-promoting microRNAs. RESULTS We identify hnRNPK as a CAV1-regulated microRNA binding protein. In the absence of CAVIN1, non-caveolar CAV1 drives localisation of hnRPNK to multi-vesicular bodies (MVBs), recruiting AsUGnA motif-containing miRNAs and causing their release within exosomes. This process is dependent on the lipid environment of membranes as shown by cholesterol depletion using methyl-β-cyclodextrin or by treatment with n-3 polyunsaturated fatty acids. Consistent with a role in bone metastasis, knockdown of hnRNPK in prostate cancer PC3 cells abolished the ability of PC3 extracellular vesicles (EV) to induce osteoclastogenesis, and biofluid EV hnRNPK is elevated in metastatic prostate and colorectal cancer. CONCLUSIONS Taken together, these results support a novel pan-cancer mechanism for CAV1-driven exosomal release of hnRNPK and associated miRNA in metastasis, which is modulated by the membrane lipid environment.
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Affiliation(s)
- Harley Robinson
- The University of Queensland Diamantina InstituteThe University of QueenslandWoolloongabbaQueenslandAustralia
- QIMR Berghofer Medical Research InstituteBrisbaneQueenslandAustralia
| | - Jayde E. Ruelcke
- The University of Queensland Diamantina InstituteThe University of QueenslandWoolloongabbaQueenslandAustralia
| | - Amanda Lewis
- School of Molecular SciencesThe University of Western AustraliaCrawleyWAAustralia
| | - Charles S. Bond
- School of Molecular SciencesThe University of Western AustraliaCrawleyWAAustralia
| | - Archa H. Fox
- School of Molecular SciencesThe University of Western AustraliaCrawleyWAAustralia
- School of Human SciencesThe University of Western AustraliaCrawleyWAAustralia
- The Harry Perkins Institute of Medical ResearchQEII Medical CentreNedlandsWAAustralia
| | - Vandhana Bharti
- QIMR Berghofer Medical Research InstituteBrisbaneQueenslandAustralia
| | - Shivangi Wani
- QIMR Berghofer Medical Research InstituteBrisbaneQueenslandAustralia
| | - Nicole Cloonan
- QIMR Berghofer Medical Research InstituteBrisbaneQueenslandAustralia
| | - Andrew Lai
- University of Queensland Centre for Clinical Research, Royal Brisbane and Women's HospitalThe University of QueenslandBrisbaneQueenslandAustralia
| | - David Margolin
- Maternal‐Fetal Medicine, Department of Obstetrics and GynecologyOchsner Clinic FoundationNew OrleansUSA
| | - Li Li
- Maternal‐Fetal Medicine, Department of Obstetrics and GynecologyOchsner Clinic FoundationNew OrleansUSA
| | - Carlos Salomon
- University of Queensland Centre for Clinical Research, Royal Brisbane and Women's HospitalThe University of QueenslandBrisbaneQueenslandAustralia
- Maternal‐Fetal Medicine, Department of Obstetrics and GynecologyOchsner Clinic FoundationNew OrleansUSA
- Department of Clinical Biochemistry and Immunology, Faculty of PharmacyUniversity of ConcepciónConcepciónChile
| | - Renée S. Richards
- QIMR Berghofer Medical Research InstituteBrisbaneQueenslandAustralia
| | - Aine Farrell
- University of Queensland Centre for Clinical Research, Royal Brisbane and Women's HospitalThe University of QueenslandBrisbaneQueenslandAustralia
| | - Robert A. Gardiner
- University of Queensland Centre for Clinical Research, Royal Brisbane and Women's HospitalThe University of QueenslandBrisbaneQueenslandAustralia
| | - Robert G. Parton
- Institute for Molecular BioscienceThe University of QueenslandSt LuciaQueenslandAustralia
- Centre for Microscopy and MicroanalysisThe University of QueenslandSt LuciaQueenslandAustralia
| | - Alexandre S. Cristino
- The University of Queensland Diamantina InstituteThe University of QueenslandWoolloongabbaQueenslandAustralia
- Griffith Institute for Drug DiscoveryGriffith UniversityBrisbaneQueenslandAustralia
| | - Michelle M. Hill
- The University of Queensland Diamantina InstituteThe University of QueenslandWoolloongabbaQueenslandAustralia
- QIMR Berghofer Medical Research InstituteBrisbaneQueenslandAustralia
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6
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Zhu G, Zhu Q, Zhang W, Hui C, Li Y, Yang M, Pang S, Li Y, Xue G, Chen H. Mitochondrial uncoupling protein 2 is regulated through heterogeneous nuclear ribonucleoprotein K in lead exposure models. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART C, TOXICOLOGY AND CARCINOGENESIS 2021; 39:1-16. [PMID: 33576715 DOI: 10.1080/26896583.2020.1854596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Synaptic plasticity plays an important role in learning and memory in the developing hippocampus. However, the precise molecular mechanism in lead exposure models remains to be studied. UCP2, an inner mitochondrial anion carrier, regulates synaptic plasticity through uncoupling neurons. And hnRNP K, an RNA binding protein, plays a role in modulating the expression of transcripts coding synaptic plasticity. We aim to investigate whether lead exposure affects UCP2 and hnRNP K expression levels. The Sprague-Dawley rats were exposed to different lead acetate concentrations (0 g/l, 0.5 g/l, 2.0 g/l) during gestational and lactational periods. PC12 cells were also exposed to different lead acetate concentrations (0 μM, 1 μM and 100 μM). We found that the expression levels of UCP2 and hnRNP K had significant declines in the lead exposure rat hippocampus and PC12 cells. Furthermore, the up-regulation of hnRNP K expression level could reverse the expression level of UCP2 in lead exposure models. In conclusion, these results suggest that lead exposure can reduce the expression level of UCP2 which is mediated by decreasing the expression level of hnRNP K.
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Affiliation(s)
- Gaochun Zhu
- Department of Anatomy, School of Medicine, Nanchang University, Nanchang, P.R. China
| | - Qian Zhu
- Department of Anatomy, School of Medicine, Nanchang University, Nanchang, P.R. China
| | - Wei Zhang
- Department of Anatomy, School of Medicine, Nanchang University, Nanchang, P.R. China
| | - Chen Hui
- Department of Anatomy, School of Medicine, Nanchang University, Nanchang, P.R. China
| | - Yuwen Li
- Queen Mary College, School of Medicine, Nanchang University, Nanchang, P.R. China
| | - Meiyuan Yang
- Department of Anatomy, School of Medicine, Nanchang University, Nanchang, P.R. China
| | - Shimin Pang
- Second Clinical College, School of Medicine, Nanchang University, Nanchang, P.R. China
| | - Yaobing Li
- Department of Anatomy, School of Medicine, Nanchang University, Nanchang, P.R. China
| | - Guoyong Xue
- Department of Anatomy, School of Medicine, Nanchang University, Nanchang, P.R. China
| | - Hongping Chen
- Department of Histology and Embryology, School of Medicine, Nanchang University, Nanchang, P.R. China
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7
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Ferent J, Zaidi D, Francis F. Extracellular Control of Radial Glia Proliferation and Scaffolding During Cortical Development and Pathology. Front Cell Dev Biol 2020; 8:578341. [PMID: 33178693 PMCID: PMC7596222 DOI: 10.3389/fcell.2020.578341] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 09/08/2020] [Indexed: 01/14/2023] Open
Abstract
During the development of the cortex, newly generated neurons migrate long-distances in the expanding tissue to reach their final positions. Pyramidal neurons are produced from dorsal progenitors, e.g., radial glia (RGs) in the ventricular zone, and then migrate along RG processes basally toward the cortex. These neurons are hence dependent upon RG extensions to support their migration from apical to basal regions. Several studies have investigated how intracellular determinants are required for RG polarity and subsequent formation and maintenance of their processes. Fewer studies have identified the influence of the extracellular environment on this architecture. This review will focus on extracellular factors which influence RG morphology and pyramidal neuronal migration during normal development and their perturbations in pathology. During cortical development, RGs are present in different strategic positions: apical RGs (aRGs) have their cell bodies located in the ventricular zone with an apical process contacting the ventricle, while they also have a basal process extending radially to reach the pial surface of the cortex. This particular conformation allows aRGs to be exposed to long range and short range signaling cues, whereas basal RGs (bRGs, also known as outer RGs, oRGs) have their cell bodies located throughout the cortical wall, limiting their access to ventricular factors. Long range signals impacting aRGs include secreted molecules present in the embryonic cerebrospinal fluid (e.g., Neuregulin, EGF, FGF, Wnt, BMP). Secreted molecules also contribute to the extracellular matrix (fibronectin, laminin, reelin). Classical short range factors include cell to cell signaling, adhesion molecules and mechano-transduction mechanisms (e.g., TAG1, Notch, cadherins, mechanical tension). Changes in one or several of these components influencing the RG extracellular environment can disrupt the development or maintenance of RG architecture on which neuronal migration relies, leading to a range of cortical malformations. First, we will detail the known long range signaling cues impacting RG. Then, we will review how short range cell contacts are also important to instruct the RG framework. Understanding how RG processes are structured by their environment to maintain and support radial migration is a critical part of the investigation of neurodevelopmental disorders.
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Affiliation(s)
- Julien Ferent
- Inserm, U 1270, Paris, France.,Sorbonne University, UMR-S 1270, IFM, Paris, France.,Institut du Fer á Moulin, Paris, France
| | - Donia Zaidi
- Inserm, U 1270, Paris, France.,Sorbonne University, UMR-S 1270, IFM, Paris, France.,Institut du Fer á Moulin, Paris, France
| | - Fiona Francis
- Inserm, U 1270, Paris, France.,Sorbonne University, UMR-S 1270, IFM, Paris, France.,Institut du Fer á Moulin, Paris, France
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8
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[Regulator proteins of actin dynamics as possible targets of antineoplastic therapies]. DER PATHOLOGE 2018; 39:225-230. [PMID: 30229281 DOI: 10.1007/s00292-018-0495-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
BACKGROUND The ability of tumor cells to leave the primary tumor is prerequisite for metastatic spread. In previous studies, we identified regulator proteins of actin reorganization with essential functions in both synaptogenesis and tumor cell migration. OBJECTIVE The aim of the studies summarized in this article is to identify signaling pathways associated with actin-related proteins that might represent potential molecular targets for antiinvasive and/or antineoplastic therapies. MATERIALS AND METHODS We used immunohistochemical analyses of protein expression as well as in vitro techniques (cell culture, fluorescence microscopy, RNAi-based knockdown of protein expression, protein biochemistry and in vivo animal experiment substitutes). RESULTS We show that phosphorylation of Abelson interactor 1 (Abi1) is essential for the adhesion and invasion of colorectal carcinoma cells and might be targeted by the tyrosine kinase inhibitor STI571/Glivec®. HnRNP K, a protein interaction partner of Abi1, is upregulated in malignant melanoma in response to ionizing radiation; this upregulation is impaired upon application of the MEK inhibitor PD98059, enhancing radiosensivity of melanoma. Edelfosin, an alkyl-lipid blocker of the Abi1 interaction partner SK3, inhibits invasion of urothelial carcinoma cells. CONCLUSION The studies summarized in this overview confirm a central role for the investigated proteins in tumor cell invasion and resistance to antineoplastic therapies and identify possible molecular targets for novel therapeutic compounds.
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9
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The RNA-Binding Protein hnRNP K Mediates the Effect of BDNF on Dendritic mRNA Metabolism and Regulates Synaptic NMDA Receptors in Hippocampal Neurons. eNeuro 2017; 4:eN-NWR-0268-17. [PMID: 29255796 PMCID: PMC5732018 DOI: 10.1523/eneuro.0268-17.2017] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 10/25/2017] [Accepted: 11/09/2017] [Indexed: 11/21/2022] Open
Abstract
Brain-derived neurotrophic factor (BDNF) is an important mediator of long-term synaptic potentiation (LTP) in the hippocampus. The local effects of BDNF depend on the activation of translation activity, which requires the delivery of transcripts to the synapse. In this work, we found that neuronal activity regulates the dendritic localization of the RNA-binding protein heterogeneous nuclear ribonucleoprotein K (hnRNP K) in cultured rat hippocampal neurons by stimulating BDNF-Trk signaling. Microarray experiments identified a large number of transcripts that are coimmunoprecipitated with hnRNP K, and about 60% of these transcripts are dissociated from the protein upon stimulation of rat hippocampal neurons with BDNF. In vivo studies also showed a role for TrkB signaling in the dissociation of transcripts from hnRNP K upon high-frequency stimulation (HFS) of medial perforant path-granule cell synapses of male rat dentate gyrus (DG). Furthermore, treatment of rat hippocampal synaptoneurosomes with BDNF decreased the coimmunoprecipitation of hnRNP K with mRNAs coding for glutamate receptor subunits, Ca2+- and calmodulin-dependent protein kinase IIβ (CaMKIIβ) and BDNF. Downregulation of hnRNP K impaired the BDNF-induced enhancement of NMDA receptor (NMDAR)-mediated mEPSC, and similar results were obtained upon inhibition of protein synthesis with cycloheximide. The results demonstrate that BDNF regulates specific populations of hnRNP-associated mRNAs in neuronal dendrites and suggests an important role of hnRNP K in BDNF-dependent forms of synaptic plasticity.
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10
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Vidaki M, Drees F, Saxena T, Lanslots E, Taliaferro MJ, Tatarakis A, Burge CB, Wang ET, Gertler FB. A Requirement for Mena, an Actin Regulator, in Local mRNA Translation in Developing Neurons. Neuron 2017; 95:608-622.e5. [PMID: 28735747 DOI: 10.1016/j.neuron.2017.06.048] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 05/17/2017] [Accepted: 06/29/2017] [Indexed: 12/16/2022]
Abstract
During neuronal development, local mRNA translation is required for axon guidance and synaptogenesis, and dysregulation of this process contributes to multiple neurodevelopmental and cognitive disorders. However, regulation of local protein synthesis in developing axons remains poorly understood. Here, we uncover a novel role for the actin-regulatory protein Mena in the formation of a ribonucleoprotein complex that involves the RNA-binding proteins HnrnpK and PCBP1 and regulates local translation of specific mRNAs in developing axons. We find that translation of dyrk1a, a Down syndrome- and autism spectrum disorders-related gene, is dependent on Mena, both in steady-state conditions and upon BDNF stimulation. We identify hundreds of additional mRNAs that associate with the Mena complex, suggesting that it plays broader role(s) in post-transcriptional gene regulation. Our work establishes a dual role for Mena in neurons, providing a potential link between regulation of actin dynamics and local translation.
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Affiliation(s)
- Marina Vidaki
- The Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
| | - Frauke Drees
- The Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Tanvi Saxena
- The Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Erwin Lanslots
- The Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Matthew J Taliaferro
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Antonios Tatarakis
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Christopher B Burge
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Eric T Wang
- The Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Frank B Gertler
- The Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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11
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Lintas C, Persico AM. Unraveling molecular pathways shared by Kabuki and Kabuki-like syndromes. Clin Genet 2017; 94:283-295. [PMID: 28139835 DOI: 10.1111/cge.12983] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Accepted: 01/19/2017] [Indexed: 12/12/2022]
Abstract
Kabuki syndrome (KS) is a rare genetic syndrome characterized by a typical facial gestalt, variable degrees of intellectual disability, organ malformations, postnatal growth retardation and skeletal abnormalities. So far, KMT2D or KDM6A mutation has been identified as the main cause of KS, accounting for 56%-75% and 3%-8% of cases, respectively. Patients without mutations in 1 of the 2 causative KS genes are often referred to as affected by Kabuki-like syndrome. Overall, they represent approximately 30% of KS cases, pointing toward substantial genetic heterogeneity for this condition. Here, we review all currently available literature describing KS-like phenotypes (or phenocopies) associated with genetic variants located in loci different from KMT2D and KDM6A . We also report on a new KS phenocopy harboring a 5 Mb de novo deletion in chr10p11.22-11.21. An enrichment analysis aimed at identifying functional Gene Ontology classes shared by the 2 known KS causative genes and by new candidate genes currently associated with KS-like phenotypes primarily converges upon abnormal chromatin remodeling and transcriptional dysregulation as pivotal to the pathophysiology of KS phenotypic hallmarks. The identification of mutations in genes belonging to the same functional pathways of KMT2D and KDM6A can help design molecular screenings targeted to KS-like phenotypes.
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Affiliation(s)
- C Lintas
- Unit of Child and Adolescent NeuroPsychiatry, University Campus Bio-Medico, Rome, Italy.,Laboratory of Molecular Psychiatry and Neurogenetics, Department of Medicine, University Campus Bio-Medico, Rome, Italy
| | - A M Persico
- Unit of Child and Adolescent NeuroPsychiatry, "G. Martino" University Hospital, University of Messina, Messina, Italy.,Mafalda Luce Center for Pervasive Developmental Disorders, Milan, Italy
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12
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Activity-dependent synapse to nucleus signaling. Neurobiol Learn Mem 2017; 138:78-84. [DOI: 10.1016/j.nlm.2016.07.024] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2016] [Revised: 07/20/2016] [Accepted: 07/23/2016] [Indexed: 11/15/2022]
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13
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Zhang J, Liu X, Lin Y, Li Y, Pan J, Zong S, Li Y, Zhou Y. HnRNP K contributes to drug resistance in acute myeloid leukemia through the regulation of autophagy. Exp Hematol 2016; 44:850-856. [PMID: 27155326 DOI: 10.1016/j.exphem.2016.04.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2016] [Revised: 04/23/2016] [Accepted: 04/26/2016] [Indexed: 01/15/2023]
Abstract
The goal of this study was to explore the role of heterogeneous nuclear ribonucleoprotein K (hnRNP K) in drug resistance through the regulation of autophagy in acute myeloid leukemia (AML). First, we used fluorescence quantitative polymerase chain reaction (PCR) to verify the connection between the expression level of hnRNP K and the level of drug resistance in AML. We then used Western blotting to determine the expression level of the autophagy-related proteins microtubule-associated protein light chain 3 I and II (LC3 I/II) after the modulation of hnRNP K by ribonucleic acid (RNA) interference. Finally, an analysis of adriamycin drug sensitivity was conducted before and after the modulation of hnRNP K expression. hnRNP K and LC3 I/II were significantly overexpressed in the bone marrow of nonremission patients and in drug-resistant cell lines; however, the expression of LC3 I/II was decreased when the expression of hnRNP K was reduced and drug sensitivity to adriamycin could be restored. hnRNP K may be involved in the development of adriamycin resistance in AML through the regulation of autophagy.
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MESH Headings
- Adolescent
- Antineoplastic Agents/pharmacology
- Antineoplastic Agents/therapeutic use
- Autophagy/drug effects
- Autophagy/genetics
- Cell Line, Tumor
- Child
- Child, Preschool
- Drug Resistance, Neoplasm/genetics
- Female
- Gene Expression
- Genotype
- Heterogeneous-Nuclear Ribonucleoprotein K/genetics
- Humans
- Leukemia, Myeloid, Acute/diagnosis
- Leukemia, Myeloid, Acute/drug therapy
- Leukemia, Myeloid, Acute/genetics
- Leukemia, Myeloid, Acute/mortality
- Male
- Microtubule-Associated Proteins/genetics
- RNA Interference
- RNA, Small Interfering/genetics
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Affiliation(s)
- JinFang Zhang
- Department of Paediatric Hematology and Oncology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong Province, China.
| | - XiaoLi Liu
- Department of Hematology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong Province, China
| | - YuDeng Lin
- Department of Paediatric Hematology and Oncology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong Province, China
| | - YuLing Li
- Department of Hematology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong Province, China
| | - JianWei Pan
- Department of Paediatric Hematology and Oncology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong Province, China
| | - Sa Zong
- Department of Paediatric Hematology and Oncology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong Province, China
| | - YongKang Li
- Department of Paediatric Hematology and Oncology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong Province, China
| | - Yang Zhou
- Department of Paediatric Hematology and Oncology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong Province, China
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14
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Lange L, Pagnamenta AT, Lise S, Clasper S, Stewart H, Akha ES, Quaghebeur G, Knight SJL, Keays DA, Taylor JC, Kini U. A de novo frameshift in HNRNPK causing a Kabuki-like syndrome with nodular heterotopia. Clin Genet 2016; 90:258-62. [PMID: 26954065 PMCID: PMC5006848 DOI: 10.1111/cge.12773] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Revised: 02/26/2016] [Accepted: 03/03/2016] [Indexed: 01/23/2023]
Abstract
Kabuki syndrome is a heterogeneous condition characterized by distinctive facial features, intellectual disability, growth retardation, skeletal abnormalities and a range of organ malformations. Although at least two major causative genes have been identified, these do not explain all cases. Here we describe a patient with a complex Kabuki-like syndrome that included nodular heterotopia, in whom testing for several single-gene disorders had proved negative. Exome sequencing uncovered a de novo c.931_932insTT variant in HNRNPK (heterogeneous nuclear ribonucleoprotein K). Although this variant was identified in March 2012, its clinical relevance could only be confirmed following the August 2015 publication of two cases with HNRNPK mutations and an overlapping phenotype that included intellectual disability, distinctive facial dysmorphism and skeletal/connective tissue abnormalities. Whilst we had attempted (unsuccessfully) to identify additional cases through existing collaborators, the two published cases were 'matched' using GeneMatcher, a web-based tool for connecting researchers and clinicians working on identical genes. Our report therefore exemplifies the importance of such online tools in clinical genetics research and the benefits of periodically reviewing cases with variants of unproven significance. Our study also suggests that loss of function variants in HNRNPK should be considered as a molecular basis for patients with Kabuki-like syndrome.
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Affiliation(s)
- L Lange
- National Institute for Health Research Biomedical Research Centre, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - A T Pagnamenta
- National Institute for Health Research Biomedical Research Centre, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - S Lise
- National Institute for Health Research Biomedical Research Centre, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - S Clasper
- Oxford Regional Genetics Service, Oxford Radcliffe Hospitals NHS Trust, The Churchill Hospital, Oxford, UK
| | - H Stewart
- Department of Clinical Genetics, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - E S Akha
- National Institute for Health Research Biomedical Research Centre, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - G Quaghebeur
- Department of Neuroradiology, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - S J L Knight
- National Institute for Health Research Biomedical Research Centre, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - D A Keays
- Institute of Molecular Pathology, Vienna, Austria
| | - J C Taylor
- National Institute for Health Research Biomedical Research Centre, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - U Kini
- Department of Clinical Genetics, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
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15
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Schoen M, Reichel JM, Demestre M, Putz S, Deshpande D, Proepper C, Liebau S, Schmeisser MJ, Ludolph AC, Michaelis J, Boeckers TM. Super-Resolution Microscopy Reveals Presynaptic Localization of the ALS/FTD Related Protein FUS in Hippocampal Neurons. Front Cell Neurosci 2016; 9:496. [PMID: 26834559 PMCID: PMC4709451 DOI: 10.3389/fncel.2015.00496] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Accepted: 12/09/2015] [Indexed: 12/12/2022] Open
Abstract
Fused in Sarcoma (FUS) is a multifunctional RNA-/DNA-binding protein, which is involved in the pathogenesis of the neurodegenerative disorders amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). A common hallmark of these disorders is the abnormal accumulation of mutated FUS protein in the cytoplasm. Under normal conditions FUS is confined to the nuclear compartment, in neurons, however, additional somatodendritic localization can be observed. In this study, we carefully analyzed the subcellular localization of endogenous FUS at synaptic sites of hippocampal neurons which are among the most affected cell types in FTD with FUS pathology. We could confirm a strong nuclear localization of FUS as well as its prominent and widespread neuronal expression throughout the adult and developing rat brain, particularly in the hippocampus, the cerebellum and the outer layers of the cortex. Intriguingly, FUS was also consistently observed at synaptic sites as detected by neuronal subcellular fractionation as well as by immunolabeling. To define a pre- and/or postsynaptic localization of FUS, we employed super-resolution fluorescence localization microscopy. FUS was found to be localized within the axon terminal in close proximity to the presynaptic vesicle protein Synaptophysin1 and adjacent to the active zone protein Bassoon, but well separated from the postsynaptic protein PSD-95. Having shown the presynaptic localization of FUS in the nervous system, a novel extranuclear role of FUS at neuronal contact sites has to be considered. Since there is growing evidence that local presynaptic translation might also be an important mechanism for plasticity, FUS - like the fragile X mental retardation protein FMRP - might act as one of the presynaptic RNA-binding proteins regulating this machinery. Our observation of presynaptic FUS should foster further investigations to determine its role in neurodegenerative diseases such as ALS and FTD.
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Affiliation(s)
- Michael Schoen
- Institute for Anatomy and Cell Biology, Ulm University Ulm, Germany
| | | | - Maria Demestre
- Institute for Anatomy and Cell Biology, Ulm University Ulm, Germany
| | - Stefan Putz
- Institute for Anatomy and Cell Biology, Ulm UniversityUlm, Germany; Department of Neurology, Ulm UniversityUlm, Germany
| | | | | | - Stefan Liebau
- Institute of Neuroanatomy, Eberhard Karls University Tübingen Tübingen, Germany
| | - Michael J Schmeisser
- Institute for Anatomy and Cell Biology, Ulm UniversityUlm, Germany; Department of Neurology, Ulm UniversityUlm, Germany
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16
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Wille M, Schümann A, Wree A, Kreutzer M, Glocker MO, Mutzbauer G, Schmitt O. The Proteome Profiles of the Cerebellum of Juvenile, Adult and Aged Rats--An Ontogenetic Study. Int J Mol Sci 2015; 16:21454-85. [PMID: 26370973 PMCID: PMC4613263 DOI: 10.3390/ijms160921454] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Revised: 08/04/2015] [Accepted: 08/25/2015] [Indexed: 11/16/2022] Open
Abstract
In this study, we searched for proteins that change their expression in the cerebellum (Ce) of rats during ontogenesis. This study focuses on the question of whether specific proteins exist which are differentially expressed with regard to postnatal stages of development. A better characterization of the microenvironment and its development may result from these study findings. A differential two-dimensional polyacrylamide gel electrophoresis (2DE) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) analysis of the samples revealed that the number of proteins of the functional classes differed depending on the developmental stages. Especially members of the functional classes of biosynthesis, regulatory proteins, chaperones and structural proteins show the highest differential expression within the analyzed stages of development. Therefore, members of these functional protein groups seem to be involved in the development and differentiation of the Ce within the analyzed development stages. In this study, changes in the expression of proteins in the Ce at different postnatal developmental stages (postnatal days (P) 7, 90, and 637) could be observed. At the same time, an identification of proteins which are involved in cell migration and differentiation was possible. Especially proteins involved in processes of the biosynthesis and regulation, the dynamic organization of the cytoskeleton as well as chaperones showed a high amount of differentially expressed proteins between the analyzed dates.
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Affiliation(s)
- Michael Wille
- Department of Anatomy, Gertrudenstr. 9, 18055 Rostock, Germany.
| | - Antje Schümann
- Department of Anatomy, Gertrudenstr. 9, 18055 Rostock, Germany.
| | - Andreas Wree
- Department of Anatomy, Gertrudenstr. 9, 18055 Rostock, Germany.
| | - Michael Kreutzer
- Proteome Center Rostock, Schillingallee 69, 18055 Rostock, Germany.
| | | | - Grit Mutzbauer
- Department of Pathology, Josef-Schneider-Str. 2, 97080 Würzburg, Germany.
| | - Oliver Schmitt
- Department of Anatomy, Gertrudenstr. 9, 18055 Rostock, Germany.
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17
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Wille M, Schümann A, Kreutzer M, Glocker MO, Wree A, Mutzbauer G, Schmitt O. The proteome profiles of the olfactory bulb of juvenile, adult and aged rats - an ontogenetic study. Proteome Sci 2015; 13:8. [PMID: 25709559 PMCID: PMC4337183 DOI: 10.1186/s12953-014-0058-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Accepted: 12/19/2014] [Indexed: 12/30/2022] Open
Abstract
Background In this study, we searched for proteins that change their expression in the olfactory bulb (oB) of rats during ontogenesis. Up to now, protein expression differences in the developing animal are not fully understood. Our investigation focused on the question whether specific proteins exist which are only expressed during different development stages. This might lead to a better characterization of the microenvironment and to a better determination of factors and candidates that influence the differentiation of neuronal progenitor cells. Results After analyzing the samples by two-dimensional polyacrylamide gel electrophoresis (2DE) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), it could be shown that the number of expressed proteins differs depending on the developmental stages. Especially members of the functional classes, like proteins of biosynthesis, regulatory proteins and structural proteins, show the highest differential expression in the stages of development analyzed. Conclusion In this study, quantitative changes in the expression of proteins in the oB at different developmental stages (postnatal days (P) 7, 90 and 637) could be observed. Furthermore, the expression of many proteins was found at specific developmental stages. It was possible to identify these proteins which are involved in processes like support of cell migration and differentiation. Electronic supplementary material The online version of this article (doi:10.1186/s12953-014-0058-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Michael Wille
- Department of Anatomy, Gertrudenstr. 9, 18055 Rostock, Germany
| | - Antje Schümann
- Department of Anatomy, Gertrudenstr. 9, 18055 Rostock, Germany
| | - Michael Kreutzer
- Proteome Center Rostock, Schillingallee 69, 18055 Rostock, Germany
| | | | - Andreas Wree
- Department of Anatomy, Gertrudenstr. 9, 18055 Rostock, Germany
| | - Grit Mutzbauer
- Department of Pathology, Josef-Schneider-Str. 2, 97080 Würzburg, Germany
| | - Oliver Schmitt
- Department of Anatomy, Gertrudenstr. 9, 18055 Rostock, Germany
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18
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Moujalled D, James JL, Yang S, Zhang K, Duncan C, Moujalled DM, Parker SJ, Caragounis A, Lidgerwood G, Turner BJ, Atkin JD, Grubman A, Liddell JR, Proepper C, Boeckers TM, Kanninen KM, Blair I, Crouch PJ, White AR. Phosphorylation of hnRNP K by cyclin-dependent kinase 2 controls cytosolic accumulation of TDP-43. Hum Mol Genet 2014; 24:1655-69. [PMID: 25410660 DOI: 10.1093/hmg/ddu578] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Cytosolic accumulation of TAR DNA binding protein 43 (TDP-43) is a major neuropathological feature of amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). However, the mechanisms involved in TDP-43 accumulation remain largely unknown. Previously, we reported that inhibitors of cyclin-dependent kinases (CDKs) prevented cytosolic stress granule accumulation of TDP-43, correlating with depletion of heterogeneous ribonucleoprotein (hnRNP) K from stress granules. In the present study, we further investigated the relationship between TDP-43 and hnRNP K and their control by CDKs. Inhibition of CDK2 abrogated the accumulation of TDP-43 into stress granules. Phosphorylated CDK2 co-localized with accumulated TDP-43 and phosphorylated hnRNP K in stress granules. Inhibition of CDK2 phosphorylation blocked phosphorylation of hnRNP K, preventing its incorporation into stress granules. Due to interaction between hnRNP K with TDP-43, the loss of hnRNP K from stress granules prevented accumulation of TDP-43. Mutation of Ser216 and Ser284 phosphorylation sites on hnRNP K inhibited hnRNP K- and TDP-43-positive stress granule formation in transfected cells. The interaction between hnRNP K and TDP-43 was further confirmed by the loss of TDP-43 accumulation following siRNA-mediated inhibition of hnRNP K expression. A substantial decrease of CDK2 and hnRNP K expression in spinal cord motor neurons in ALS patients demonstrates a potential key role for these proteins in ALS and TDP-43 accumulation, indicating that further investigation of the association between hnRNP K and TDP-43 is warranted. Understanding how kinase activity modulates TDP-43 accumulation may provide new pharmacological targets for disease intervention.
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Affiliation(s)
| | | | - Shu Yang
- The Australian School of Advanced Medicine, Macquarie University, Sydney, NSW 2109, Australia
| | - Katharine Zhang
- The Australian School of Advanced Medicine, Macquarie University, Sydney, NSW 2109, Australia
| | | | - Donia M Moujalled
- Department of Medical Biology, The University of Melbourne, Melbourne, VIC 3010, Australia, The Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Melbourne, VIC 3052, Australia
| | | | | | | | - Bradley J Turner
- Florey Institute of Neuroscience and Mental Health, Parkville, VIC 3010, Australia
| | - Julie D Atkin
- The Australian School of Advanced Medicine, Macquarie University, Sydney, NSW 2109, Australia
| | | | | | - Christian Proepper
- Anatomy and Cell Biology, University of Ulm, Albert-Einstein Allee 11, 89081 Ulm, Germany
| | - Tobias M Boeckers
- Anatomy and Cell Biology, University of Ulm, Albert-Einstein Allee 11, 89081 Ulm, Germany
| | - Katja M Kanninen
- A.I. Virtanen Institute for Molecular Sciences, Laboratory of Molecular Brain Research, University of Eastern Finland, Kuopio, Finland
| | - Ian Blair
- The Australian School of Advanced Medicine, Macquarie University, Sydney, NSW 2109, Australia
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19
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Steinestel K, Gläsle F, Brüderlein S, Steinestel J, Pröpper C, Möller P. [Abelson interactor 1 (Abi1) in colorectal cancer. From synaptic plasticity to tumor cell migration]. DER PATHOLOGE 2014; 34 Suppl 2:189-94. [PMID: 24196611 DOI: 10.1007/s00292-013-1810-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
BACKGROUND Invasion and metastatic dissemination of tumor cells defines the prognosis of patients with colorectal cancer (CRC). The Abelson interactor 1 (Abi1), a 65 kD substrate of the eponymous Abelson tyrosine kinase, interacts with phosphatidylinositol-3-kinase (PI3K) and heterogeneous nuclear ribonucleoprotein K (hnRNP K) and is a key regulator of cytoskeletal reorganization during synaptic maturation and cellular migration. AIM The aim of this study was the analysis of Abi1 expression patterns and to elucidate the role in cytoskeletal reorganization in colorectal carcinoma cells. MATERIAL AND METHODS The methods used in this study were immunohistochemistry; immunofluorescence microscopy; liposomal transfection and protein analysis by Western blotting. RESULTS The results showed that Abi1 is expressed at the invasive front of colorectal carcinomas and localizes to the leading edge of lamellipodia in cultured colorectal carcinoma cells. A phosphorylated isoform of Abi1 that stains positively in these microcompartments disappears after treatment with the tyrosine kinase inhibitor STI571 (Glivec®). The RNA interference (RNAi) approach knockdown of Abi1 as well as treatment with STI571 induce a shift in cellular morphology from broad lamellipodia-like to thin filopodia-like cellular protrusions. DISCUSSION The initial results support a central role for phosphorylated Abi1 in the formation of lamellipodia-like cellular protrusions as a prerequisite for cellular migration of colorectal carcinoma cells. As phosphorylation of Abi1 could be pharmaceutically targeted with STI571, this indicates a possible therapeutic option to prevent the gain of a metastatic phenotype in colorectal cancer. This possibility will be further evaluated in ongoing research.
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Affiliation(s)
- K Steinestel
- Institut für Radiobiologie der Bundeswehr, Neuherbergstr. 11, 80937, München, Deutschland,
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20
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Lee PT, Chao PK, Ou LC, Chuang JY, Lin YC, Chen SC, Chang HF, Law PY, Loh HH, Chao YS, Su TP, Yeh SH. Morphine drives internal ribosome entry site-mediated hnRNP K translation in neurons through opioid receptor-dependent signaling. Nucleic Acids Res 2014; 42:13012-25. [PMID: 25361975 PMCID: PMC4245930 DOI: 10.1093/nar/gku1016] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Heterogeneous nuclear ribonucleoprotein K (hnRNP K) binds to the promoter region of mu-opioid receptor (MOR) to regulate its transcriptional activity. How hnRNP K contributes to the analgesic effects of morphine, however, is largely unknown. We provide evidence that morphine increases hnRNP K protein expression via MOR activation in rat primary cortical neurons and HEK-293 cells expressing MORs, without increasing mRNA levels. Using the bicistronic reporter assay, we examined whether morphine-mediated accumulation of hnRNP K resulted from translational control. We identified potential internal ribosome entry site elements located in the 5′ untranslated regions of hnRNP K transcripts that were regulated by morphine. This finding suggests that internal translation contributes to the morphine-induced accumulation of hnRNP K protein in regions of the central nervous system correlated with nociceptive and antinociceptive modulatory systems in mice. Finally, we found that down-regulation of hnRNP K mediated by siRNA attenuated morphine-induced hyperpolarization of membrane potential in AtT20 cells. Silencing hnRNP K expression in the spinal cord increased nociceptive sensitivity in wild-type mice, but not in MOR-knockout mice. Thus, our findings identify the role of translational control of hnRNP K in morphine-induced analgesia through activation of MOR.
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Affiliation(s)
- Pin-Tse Lee
- Institute of Biotechnology and Pharmaceutical Research, National Health Research Institutes, Miaoli County 35053, Taiwan, ROC
| | - Po-Kuan Chao
- Institute of Biotechnology and Pharmaceutical Research, National Health Research Institutes, Miaoli County 35053, Taiwan, ROC
| | - Li-Chin Ou
- Institute of Biotechnology and Pharmaceutical Research, National Health Research Institutes, Miaoli County 35053, Taiwan, ROC
| | - Jian-Ying Chuang
- The PhD Program for Neural Regenerative Medicine, Taipei Medical University, Taipei 110, Taiwan, ROC
| | - Yen-Chang Lin
- Graduate Institute of Biotechnology, Chinese Culture University, Taipei 11114, Taiwan, ROC
| | - Shu-Chun Chen
- Institute of Biotechnology and Pharmaceutical Research, National Health Research Institutes, Miaoli County 35053, Taiwan, ROC
| | - Hsiao-Fu Chang
- Institute of Biotechnology and Pharmaceutical Research, National Health Research Institutes, Miaoli County 35053, Taiwan, ROC
| | - Ping-Yee Law
- Department of Pharmacology, University of Minnesota, Medical School, Minneapolis, MN 55455, USA
| | - Horace H Loh
- Department of Pharmacology, University of Minnesota, Medical School, Minneapolis, MN 55455, USA
| | - Yu-Sheng Chao
- Institute of Biotechnology and Pharmaceutical Research, National Health Research Institutes, Miaoli County 35053, Taiwan, ROC
| | - Tsung-Ping Su
- Cellular Pathobiology Section, Intramural Research Program, National Institute on Drug Abuse, Baltimore, MD 21224, USA
| | - Shiu-Hwa Yeh
- Institute of Biotechnology and Pharmaceutical Research, National Health Research Institutes, Miaoli County 35053, Taiwan, ROC
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21
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Hancarova M, Puchmajerova A, Drabova J, Karaskova E, Vlckova M, Sedlacek Z. Deletions of 9q21.3 including NTRK2 are associated with severe phenotype. Am J Med Genet A 2014; 167A:264-7. [PMID: 25348648 DOI: 10.1002/ajmg.a.36797] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Accepted: 09/04/2014] [Indexed: 01/19/2023]
Affiliation(s)
- Miroslava Hancarova
- Department of Biology and Medical Genetics, Charles University 2nd Faculty of Medicine and University Hospital Motol, Prague, Czech Republic
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22
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Abstract
Heterogeneous nuclear ribonucleoprotein K (hnRNP K) is an RNA-binding protein implicated in RNA metabolism. Here, we investigated the role of hnRNP K in synapse function. We demonstrated that hnRNP K regulates dendritic spine density and long-term potentiation (LTP) in cultured hippocampal neurons from embryonic rats. LTP requires the extracellular signal-regulated kinase (ERK)1/2-mediated phosphorylation and cytoplasmic accumulation of hnRNP K. Moreover, hnRNP K knockdown prevents ERK cascade activation and GluA1-S845 phosphorylation and surface delivery, which are essential steps for LTP. These findings establish hnRNP K as a new critical regulator of synaptic transmission and plasticity in hippocampal neurons.
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23
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Steinestel K, Brüderlein S, Lennerz JK, Steinestel J, Kraft K, Pröpper C, Meineke V, Möller P. Expression and Y435-phosphorylation of Abelson interactor 1 (Abi1) promotes tumour cell adhesion, extracellular matrix degradation and invasion by colorectal carcinoma cells. Mol Cancer 2014; 13:145. [PMID: 24913355 PMCID: PMC4066275 DOI: 10.1186/1476-4598-13-145] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Accepted: 06/02/2014] [Indexed: 12/14/2022] Open
Abstract
Background The Abelson tyrosine kinase (c-Abl) inhibitor STI571 (Glivec®) has been shown to effectively inhibit colorectal cancer cell migration and invasion. The c-Abl substrate abelson interactor 1 (Abi1) is a key regulator of actin reorganization and upregulated in colorectal carcinoma. The specific role of Abi1 in relation to extracellular matrix degradation and effects of targeting Abi1 phosphorylation have not yet been examined. Here, we investigated the role of Abi1 in relation to invasive properties in colorectal cancer. Methods and results In 56 primary human colorectal carcinoma samples, we found overexpression of Abi1 in 39% at the invasive edge of the tumour, associated with an infiltrative phenotype and high-grade tumour cell budding (p = 0.001). To explore the role of Abi1 in vitro, we employed the Abi1 expressing and KRAS-mutated CHD1 model and performed matrix degradation assays that showed Abi1 localization at specific sites of matrix degradation. Moreover, quantification of matrix dissolution demonstrated suppression after RNAi knockdown of Abi1 by 95% (p = 0.001). Importantly, treatment with STI571 did abolish Abi1 Y435-phosphorylation, suppressed the matrix dissolution, decreased fibronectin attachment, and suppressed cell invasion through reconstituted extracellular matrix. Conclusion Our data indicate that phosphorylated Abi1 contributes to the invasive properties of colorectal cancer.
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Affiliation(s)
- Konrad Steinestel
- Bundeswehr Institute of Radiobiology, Neuherbergstr, 11, 80937 Munich, Germany.
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24
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Sala C, Segal M. Dendritic spines: the locus of structural and functional plasticity. Physiol Rev 2014; 94:141-88. [PMID: 24382885 DOI: 10.1152/physrev.00012.2013] [Citation(s) in RCA: 338] [Impact Index Per Article: 33.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
The introduction of high-resolution time lapse imaging and molecular biological tools has changed dramatically the rate of progress towards the understanding of the complex structure-function relations in synapses of central spiny neurons. Standing issues, including the sequence of molecular and structural processes leading to formation, morphological change, and longevity of dendritic spines, as well as the functions of dendritic spines in neurological/psychiatric diseases are being addressed in a growing number of recent studies. There are still unsettled issues with respect to spine formation and plasticity: Are spines formed first, followed by synapse formation, or are synapses formed first, followed by emergence of a spine? What are the immediate and long-lasting changes in spine properties following exposure to plasticity-producing stimulation? Is spine volume/shape indicative of its function? These and other issues are addressed in this review, which highlights the complexity of molecular pathways involved in regulation of spine structure and function, and which contributes to the understanding of central synaptic interactions in health and disease.
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Grabrucker S, Proepper C, Mangus K, Eckert M, Chhabra R, Schmeisser MJ, Boeckers TM, Grabrucker AM. The PSD protein ProSAP2/Shank3 displays synapto-nuclear shuttling which is deregulated in a schizophrenia-associated mutation. Exp Neurol 2013; 253:126-37. [PMID: 24382453 DOI: 10.1016/j.expneurol.2013.12.015] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Revised: 12/12/2013] [Accepted: 12/20/2013] [Indexed: 12/11/2022]
Abstract
Recently, mutations in ProSAP2/Shank3 have been discovered as one of the genetic factors for schizophrenia (SCZ). Here, we show that the postsynaptic density protein ProSAP2/Shank3 undergoes activity dependent synapse-to-nucleus shuttling in hippocampal neurons. Our study shows that the de novo mutation (R1117X) in ProSAP2/Shank3 that was identified in a patient with SCZ leads to an accumulation of mutated ProSAP2/Shank3 within the nucleus independent of synaptic activity. Furthermore, we identified novel nuclear ProSAP2/Shank3 interaction partners. Nuclear localization of mutated ProSAP2/Shank3 alters transcription of several genes, among them already identified genetic risk factors for SCZ such as Synaptotagmin 1 and LRRTM1. Comparing the SCZ mutation of ProSAP2/Shank3 to the knockdown of ProSAP2/Shank3 we found some shared features such as reduced synaptic density in neuronal cultures. However, hippocampal neurons expressing the ProSAP2/Shank3 SCZ mutation furthermore show altered E/I ratio and reduced dendritic branching. Thus, we conclude that the uncoupling of ProSAP2/Shank3 nuclear shuttling from synaptic activity may represent a molecular mechanism that contributes to the pathology of SCZ in patients with mutations in ProSAP2/Shank3.
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Affiliation(s)
- Stefanie Grabrucker
- WG Molecular Analysis of Synaptopathies, Neurology Dept., Neurocenter of Ulm University, Albert-Einstein Allee 11, 89081 Ulm, Germany; Institute for Anatomy and Cell Biology, Ulm University, Albert-Einstein Allee 11, 89081 Ulm, Germany
| | - Christian Proepper
- Institute for Anatomy and Cell Biology, Ulm University, Albert-Einstein Allee 11, 89081 Ulm, Germany
| | - Katharina Mangus
- WG Molecular Analysis of Synaptopathies, Neurology Dept., Neurocenter of Ulm University, Albert-Einstein Allee 11, 89081 Ulm, Germany
| | - Matti Eckert
- WG Molecular Analysis of Synaptopathies, Neurology Dept., Neurocenter of Ulm University, Albert-Einstein Allee 11, 89081 Ulm, Germany
| | - Resham Chhabra
- WG Molecular Analysis of Synaptopathies, Neurology Dept., Neurocenter of Ulm University, Albert-Einstein Allee 11, 89081 Ulm, Germany
| | - Michael J Schmeisser
- Institute for Anatomy and Cell Biology, Ulm University, Albert-Einstein Allee 11, 89081 Ulm, Germany
| | - Tobias M Boeckers
- Institute for Anatomy and Cell Biology, Ulm University, Albert-Einstein Allee 11, 89081 Ulm, Germany
| | - Andreas M Grabrucker
- WG Molecular Analysis of Synaptopathies, Neurology Dept., Neurocenter of Ulm University, Albert-Einstein Allee 11, 89081 Ulm, Germany; Institute for Anatomy and Cell Biology, Ulm University, Albert-Einstein Allee 11, 89081 Ulm, Germany.
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Proepper C, Putz S, Russell R, Boeckers TM, Liebau S. The Kvβ2 subunit of voltage-gated potassium channels is interacting with ProSAP2/Shank3 in the PSD. Neuroscience 2013; 261:133-43. [PMID: 24211303 DOI: 10.1016/j.neuroscience.2013.10.045] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Revised: 10/21/2013] [Accepted: 10/22/2013] [Indexed: 01/18/2023]
Abstract
The postsynaptic density is an electron dense meshwork composed of a variety of molecules facilitating neuronal signal transmission. ProSAP2/Shank3 represents a crucial player at postsynaptic sites, assembling large multimeric platforms and anchoring numerous other molecules, thereby linking the functional synapse with the cytoskeleton. ProSAP2/Shank3 is also implicated in the pathogenesis of numerous diseases, including autism spectrum disorders. KvBeta2 (Kvβ2) on the other hand serves as a regulatory subunit of voltage-gated potassium channels. Kvβ2 is located at various sites in the neuron including the axon (binding to Kv1.2), the dendrites (binding to Kv4.2) and the synapse. Binding of Kvβ2 to either Kv1.2 or Kv4 modulates not only the channel conformation but directs targeting of the channel protein complex to distinct loci within the cell. Thus an interaction between ProSAP2 and Kvβ2 could have important roles at diverse cellular compartments and moreover during maturation stages. We report here on the direct protein-protein interaction of the postsynaptic density anchoring molecule ProSAP2 and the potassium channel subunit Kvβ2, initially identified in a yeast-two-hybrid-screen. Furthermore, we characterize this interaction at synapses using primary hippocampal neurons in vitro.
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Affiliation(s)
- C Proepper
- Institute for Anatomy and Cell Biology, Ulm University, Ulm, Germany
| | - S Putz
- Institute for Anatomy and Cell Biology, Ulm University, Ulm, Germany
| | - R Russell
- Department of Internal Medicine 1, Ulm University Hospital, Ulm, Germany
| | - T M Boeckers
- Institute for Anatomy and Cell Biology, Ulm University, Ulm, Germany
| | - S Liebau
- Institute for Anatomy and Cell Biology, Ulm University, Ulm, Germany; Institute of Neuroanatomy, University of Tuebingen, Tuebingen, Germany.
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Hazai D, Szudoczki R, Ding J, Soderling SH, Weinberg RJ, Sótonyi P, Rácz B. Ultrastructural abnormalities in CA1 hippocampus caused by deletion of the actin regulator WAVE-1. PLoS One 2013; 8:e75248. [PMID: 24086480 PMCID: PMC3783472 DOI: 10.1371/journal.pone.0075248] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Accepted: 08/12/2013] [Indexed: 11/18/2022] Open
Abstract
By conveying signals from the small GTPase family of proteins to the Arp2/3 complex, proteins of the WAVE family facilitate actin remodeling. The WAVE-1 isoform is expressed at high levels in brain, where it plays a role in normal synaptic processing, and is implicated in hippocampus-dependent memory retention. We used electron microscopy to determine whether synaptic structure is modified in the hippocampus of WAVE-1 knockout mice, focusing on the neuropil of CA1 stratum radiatum. Mice lacking WAVE-1 exhibited alterations in the morphology of both axon terminals and dendritic spines; the relationship between the synaptic partners was also modified. The abnormal synaptic morphology we observed suggests that signaling through WAVE-1 plays a critical role in establishing normal synaptic architecture in the rodent hippocampus.
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Affiliation(s)
- Diána Hazai
- Department of Anatomy and Histology, Faculty of Veterinary Science, Szent István University, Budapest, Hungary
| | - Róbert Szudoczki
- Department of Anatomy and Histology, Faculty of Veterinary Science, Szent István University, Budapest, Hungary
| | - Jindong Ding
- Department of Ophthalmology, Duke Eye Center, Duke University, Durham, North Carolina, United States of America
| | - Scott H. Soderling
- Departments of Cell Biology and Neurobiology, Duke University, Durham, North Carolina, United States of America
| | - Richard J. Weinberg
- Department of Cell Biology & Physiology and Neuroscience Center, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Péter Sótonyi
- Department of Anatomy and Histology, Faculty of Veterinary Science, Szent István University, Budapest, Hungary
| | - Bence Rácz
- Department of Anatomy and Histology, Faculty of Veterinary Science, Szent István University, Budapest, Hungary
- * E-mail:
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Linta L, Boeckers TM, Kleger A, Liebau S. Calcium activated potassium channel expression during human iPS cell-derived neurogenesis. Ann Anat 2013; 195:303-311. [PMID: 23587809 DOI: 10.1016/j.aanat.2013.02.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2012] [Revised: 02/05/2013] [Accepted: 02/27/2013] [Indexed: 01/11/2023]
Abstract
The family of calcium activated potassium channels of low and intermediate conductance, known as SK channels, consists of four members (SK1-4). These channels are widely expressed throughout the organism and involved in various cellular processes, such as the afterhyperpolarization in excitable cells but also in differentiation processes of various tissues. To date, the role of SK channels in developmental processes has been merely a marginal focus of investigation, although it is well accepted that cell differentiation and maturation affect the expression patterns of certain ion channels. Recently, several studies from our laboratory delineated the influence of SK channel expression and their respective activity on cytoskeletal reorganization in neural and pluripotent stem cells and regulation of cell fate determination toward the cardiac lineage in human and mouse pluripotent stem cells. Herein, we have now analyzed SK channel expression patterns and distribution at various stages of human induced pluripotent stem cell-derived neurogenesis particularly focusing on undifferentiated iPS cells, neural progenitors and mature neurons. All family members could be detected starting at the iPS cell level and were differentially expressed during the subsequent maturation process. Intriguingly, we found obvious discrepancies between mRNA and protein expression pointing toward a complex regulatory mechanism. Inhibition of SK channels with either apamin or clotrimazol did not have any significant effects on the speed or amount of neurogenesis in vitro. The abundance and specific regulation of SK channel expression during iPS cell differentiation indicates distinct roles of these ion channels not only for the cardiac but also for neuronal cell differentiation and in vitro neurogenesis.
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Affiliation(s)
- Leonhard Linta
- Institute for Anatomy & Cell Biology, Ulm University, Ulm, Germany
| | | | - Alexander Kleger
- Department of Internal Medicine I, Ulm University, Ulm, Germany.
| | - Stefan Liebau
- Institute for Anatomy & Cell Biology, Ulm University, Ulm, Germany.
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Swanger SA, Bassell GJ. Dendritic protein synthesis in the normal and diseased brain. Neuroscience 2012; 232:106-27. [PMID: 23262237 DOI: 10.1016/j.neuroscience.2012.12.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2012] [Revised: 11/21/2012] [Accepted: 12/01/2012] [Indexed: 01/25/2023]
Abstract
Synaptic activity is a spatially limited process that requires a precise, yet dynamic, complement of proteins within the synaptic micro-domain. The maintenance and regulation of these synaptic proteins is regulated, in part, by local mRNA translation in dendrites. Protein synthesis within the postsynaptic compartment allows neurons tight spatial and temporal control of synaptic protein expression, which is critical for proper functioning of synapses and neural circuits. In this review, we discuss the identity of proteins synthesized within dendrites, the receptor-mediated mechanisms regulating their synthesis, and the possible roles for these locally synthesized proteins. We also explore how our current understanding of dendritic protein synthesis in the hippocampus can be applied to new brain regions and to understanding the pathological mechanisms underlying varied neurological diseases.
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Affiliation(s)
- S A Swanger
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - G J Bassell
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA; Department of Neurology, Emory University School of Medicine, Atlanta, GA 30322, USA.
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Steinestel K, Brüderlein S, Steinestel J, Märkl B, Schwerer MJ, Arndt A, Kraft K, Pröpper C, Möller P. Expression of Abelson interactor 1 (Abi1) correlates with inflammation, KRAS mutation and adenomatous change during colonic carcinogenesis. PLoS One 2012; 7:e40671. [PMID: 22808230 PMCID: PMC3393686 DOI: 10.1371/journal.pone.0040671] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2012] [Accepted: 06/11/2012] [Indexed: 01/29/2023] Open
Abstract
Background Abelson interactor 1 (Abi1) is an important regulator of actin dynamics during cytoskeletal reorganization. In this study, our aim was to investigate the expression of Abi1 in colonic mucosa with and without inflammation, colonic polyps, colorectal carcinomas (CRC) and metastases as well as in CRC cell lines with respect to BRAF/KRAS mutation status and to find out whether introduction of KRAS mutation or stimulation with TNFalpha enhances Abi1 protein expression in CRC cells. Methodology/Principal Findings We immunohistochemically analyzed Abi1 protein expression in 126 tissue specimens from 95 patients and in 5 colorectal carcinoma cell lines with different mutation status by western immunoblotting. We found that Abi1 expression correlated positively with KRAS, but not BRAF mutation status in the examined tissue samples. Furthermore, Abi1 is overexpressed in inflammatory mucosa, sessile serrated polyps and adenomas, tubular adenomas, invasive CRC and CRC metastasis when compared to healthy mucosa and BRAF-mutated as well as KRAS wild-type hyperplastic polyps. Abi1 expression in carcinoma was independent of microsatellite stability of the tumor. Abi1 protein expression correlated with KRAS mutation in the analyzed CRC cell lines, and upregulation of Abi1 could be induced by TNFalpha treatment as well as transfection of wild-type CRC cells with mutant KRAS. The overexpression of Abi1 could be abolished by treatment with the PI3K-inhibitor Wortmannin after KRAS transfection. Conclusions/Significance Our results support a role for Abi1 as a downstream target of inflammatory response and adenomatous change as well as oncogenic KRAS mutation via PI3K, but not BRAF activation. Furthermore, they highlight a possible role for Abi1 as a marker for early KRAS mutation in hyperplastic polyps. Since the protein is a key player in actin dynamics, our data encourages further studies concerning the exact role of Abi1 in actin reorganization upon enhanced KRAS/PI3K signalling during colonic tumorigenesis.
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