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Koch D, Kho AL, Fukuzawa A, Alexandrovich A, Vanaanen KJ, Beavil A, Pfuhl M, Rees M, Gautel M. Obscurin Rho GEF domains are phosphorylated by MST-family kinases but do not exhibit nucleotide exchange factor activity towards Rho GTPases in vitro. PLoS One 2023; 18:e0284453. [PMID: 37079638 PMCID: PMC10118190 DOI: 10.1371/journal.pone.0284453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Accepted: 04/01/2023] [Indexed: 04/21/2023] Open
Abstract
Obscurin is a giant muscle protein (>800 kDa) featuring multiple signalling domains, including an SH3-DH-PH domain triplet from the Trio-subfamily of guanosine nucleotide exchange factors (GEFs). While previous research suggests that these domains can activate the small GTPases RhoA and RhoQ in cells, in vitro characterization of these interactions using biophysical techniques has been hampered by the intrinsic instability of obscurin GEF domains. To study substrate specificity, mechanism and regulation of obscurin GEF function by individual domains, we successfully optimized recombinant production of obscurin GEF domains and found that MST-family kinases phosphorylate the obscurin DH domain at Thr5798. Despite extensive testing of multiple GEF domain fragments, we did not detect any nucleotide exchange activity in vitro against 9 representative small GTPases. Bioinformatic analyses show that obscurin differs from other Trio-subfamily GEFs in several important aspects. While further research is necessary to evaluate obscurin GEF activity in vivo, our results indicate that obscurin has atypical GEF domains that, if catalytically active at all, are subject to complex regulation.
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Affiliation(s)
- Daniel Koch
- Randall Centre for Cell and Molecular Biophysics, King’s College London, London, United Kingdom
| | - Ay Lin Kho
- Randall Centre for Cell and Molecular Biophysics, King’s College London, London, United Kingdom
| | - Atsushi Fukuzawa
- Randall Centre for Cell and Molecular Biophysics, King’s College London, London, United Kingdom
| | - Alexander Alexandrovich
- Randall Centre for Cell and Molecular Biophysics, King’s College London, London, United Kingdom
| | - Kutti J. Vanaanen
- Randall Centre for Cell and Molecular Biophysics, King’s College London, London, United Kingdom
| | - Andrew Beavil
- Randall Centre for Cell and Molecular Biophysics, King’s College London, London, United Kingdom
| | - Mark Pfuhl
- Randall Centre for Cell and Molecular Biophysics, King’s College London, London, United Kingdom
| | - Martin Rees
- Randall Centre for Cell and Molecular Biophysics, King’s College London, London, United Kingdom
| | - Mathias Gautel
- Randall Centre for Cell and Molecular Biophysics, King’s College London, London, United Kingdom
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2
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Yamaguchi Y, Kadowaki T, Aibara N, Ohyama K, Okamoto K, Sakai E, Tsukuba T. Coronin1C Is a GDP-Specific Rab44 Effector That Controls Osteoclast Formation by Regulating Cell Motility in Macrophages. Int J Mol Sci 2022; 23:ijms23126619. [PMID: 35743062 PMCID: PMC9224296 DOI: 10.3390/ijms23126619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 06/11/2022] [Accepted: 06/13/2022] [Indexed: 11/17/2022] Open
Abstract
Osteoclasts are multinucleated bone-resorbing cells that are formed by the fusion of macrophages. Recently, we identified Rab44, a large Rab GTPase, as an upregulated gene during osteoclast differentiation that negatively regulates osteoclast differentiation. However, the molecular mechanisms by which Rab44 negatively regulates osteoclast differentiation remain unknown. Here, we found that the GDP form of Rab44 interacted with the actin-binding protein, Coronin1C, in murine macrophages. Immunoprecipitation experiments revealed that the interaction of Rab44 and Coronin1C occurred in wild-type and a dominant-negative (DN) mutant of Rab44, but not in a constitutively active (CA) mutant of Rab44. Consistent with these findings, the expression of the CA mutant inhibited osteoclast differentiation, whereas that of the DN mutant enhanced this differentiation. Using a phase-contrast microscope, Coronin1C-knockdown osteoclasts apparently impaired multinuclear formation. Moreover, Coronin1C knockdown impaired the migration and chemotaxis of RAW-D macrophages. An in vivo experimental system demonstrated that Coronin1C knockdown suppresses osteoclastogenesis. Therefore, the decreased cell formation and fusion of Coronin1C-depleted osteoclasts might be due to the decreased migration of Coronin1C-knockdown macrophages. These results indicate that Coronin1C is a GDP-specific Rab44 effector that controls osteoclast formation by regulating cell motility in macrophages.
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Affiliation(s)
- Yu Yamaguchi
- Department of Dental Pharmacology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8588, Japan; (Y.Y.); (E.S.)
| | - Tomoko Kadowaki
- Department of Frontier Oral Science, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8588, Japan;
| | - Nozomi Aibara
- Department of Pharmacy Practice, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8588, Japan; (N.A.); (K.O.)
| | - Kaname Ohyama
- Department of Pharmacy Practice, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8588, Japan; (N.A.); (K.O.)
| | - Kuniaki Okamoto
- Department of Dental Pharmacology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8525, Japan;
| | - Eiko Sakai
- Department of Dental Pharmacology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8588, Japan; (Y.Y.); (E.S.)
| | - Takayuki Tsukuba
- Department of Dental Pharmacology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8588, Japan; (Y.Y.); (E.S.)
- Correspondence: ; Tel.: +81-95-819-7652
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3
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Huang M, Wang Y. GLOBAL AND TARGETED PROFILING OF GTP-BINDING PROTEINS IN BIOLOGICAL SAMPLES BY MASS SPECTROMETRY. MASS SPECTROMETRY REVIEWS 2021; 40:215-235. [PMID: 32519381 PMCID: PMC7725852 DOI: 10.1002/mas.21637] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 05/04/2020] [Accepted: 05/15/2020] [Indexed: 05/05/2023]
Abstract
GTP-binding proteins are among the most important enzyme families that are involved in a plethora of biological processes. However, owing to the enormous diversity of the nucleotide-binding protein family, comprehensive analyses of the expression level, structure, activity, and regulatory mechanisms of GTP-binding proteins remain challenging with the use of conventional approaches. The many advances in mass spectrometry (MS) instrumentation and data acquisition methods, together with a variety of enrichment approaches in sample preparation, render MS a powerful tool for the comprehensive characterizations of the activities and expression levels of various GTP-binding proteins. We review herein the recent developments in the application of MS-based techniques, together with general and widely used affinity enrichment approaches, for the proteome-wide and targeted capture, identification, and quantification of GTP-binding proteins. The working principles, advantages, and limitations of various strategies for profiling the expression level, activity, posttranslational modifications, and interactome of GTP-binding proteins are discussed. It can be envisaged that future applications of MS-based proteomics will lead to a better understanding about the roles of GTP-binding proteins in different biological processes and human diseases. © 2020 John Wiley & Sons Ltd. Mass Spec Rev.
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Affiliation(s)
- Ming Huang
- Environmental Toxicology Graduate Program, University of California Riverside, Riverside, CA 92521, USA
| | - Yinsheng Wang
- Environmental Toxicology Graduate Program, University of California Riverside, Riverside, CA 92521, USA
- Department of Chemistry, University of California Riverside, Riverside, CA 92521, USA
- Correspondence author: Yinsheng Wang. Telephone: (951)827-2700;
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4
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Small GTPases of the Rab and Arf Families: Key Regulators of Intracellular Trafficking in Neurodegeneration. Int J Mol Sci 2021; 22:ijms22094425. [PMID: 33922618 PMCID: PMC8122874 DOI: 10.3390/ijms22094425] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 04/14/2021] [Accepted: 04/20/2021] [Indexed: 12/11/2022] Open
Abstract
Small guanosine triphosphatases (GTPases) of the Rab and Arf families are key regulators of vesicle formation and membrane trafficking. Membrane transport plays an important role in the central nervous system. In this regard, neurons require a constant flow of membranes for the correct distribution of receptors, for the precise composition of proteins and organelles in dendrites and axons, for the continuous exocytosis/endocytosis of synaptic vesicles and for the elimination of dysfunctional proteins. Thus, it is not surprising that Rab and Arf GTPases have been associated with neurodegenerative diseases such as Alzheimer’s and Parkinson’s. Both pathologies share characteristics such as the presence of protein aggregates and/or the fragmentation of the Golgi apparatus, hallmarks that have been related to both Rab and Arf GTPases functions. Despite their relationship with neurodegenerative disorders, very few studies have focused on the role of these GTPases in the pathogenesis of neurodegeneration. In this review, we summarize their importance in the onset and progression of Alzheimer’s and Parkinson’s diseases, as well as their emergence as potential therapeutical targets for neurodegeneration.
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Binda C, Génier S, Degrandmaison J, Picard S, Fréchette L, Jean S, Marsault E, Parent JL. L-type prostaglandin D synthase regulates the trafficking of the PGD 2 DP1 receptor by interacting with the GTPase Rab4. J Biol Chem 2019; 294:16865-16883. [PMID: 31575663 DOI: 10.1074/jbc.ra119.008233] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 09/27/2019] [Indexed: 12/28/2022] Open
Abstract
Accumulating evidence indicates that G protein-coupled receptors (GPCRs) interact with Rab GTPases during their intracellular trafficking. How GPCRs recruit and activate the Rabs is unclear. Here, we report that depletion of endogenous L-type prostaglandin D synthase (L-PGDS) in HeLa cells inhibited recycling of the prostaglandin D2 (PGD2) DP1 receptor (DP1) to the cell surface after agonist-induced internalization and that L-PGDS overexpression had the opposite effect. Depletion of endogenous Rab4 prevented l-PGDS-mediated recycling of DP1, and l-PGDS depletion inhibited Rab4-dependent recycling of DP1, indicating that both proteins are mutually involved in this pathway. DP1 stimulation promoted its interaction through its intracellular C terminus with Rab4, which was increased by l-PGDS. Confocal microscopy revealed that DP1 activation induces l-PGDS/Rab4 co-localization. l-PGDS/Rab4 and DP1/Rab4 co-immunoprecipitation levels were increased by DP1 agonist treatment. Pulldown assays with purified GST-l-PGDS and His6-Rab4 indicated that both proteins interact directly. l-PGDS interacted preferentially with the inactive, GDP-locked Rab4S22N variant rather than with WT Rab4 or with constitutively active Rab4Q67L proteins. Overexpression and depletion experiments disclosed that l-PGDS partakes in Rab4 activation following DP1 stimulation. Experiments with deletion mutants and synthetic peptides revealed that amino acids 85-92 in l-PGDS are involved in its interaction with Rab4 and in its effect on DP1 recycling. Of note, GTPγS loading and time-resolved FRET assays with purified proteins suggested that l-PGDS enhances GDP-GTP exchange on Rab4. Our results reveal how l-PGDS, which produces the agonist for DP1, regulates DP1 recycling by participating in Rab4 recruitment and activation.
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Affiliation(s)
- Chantal Binda
- Département de Médecine, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Québec J1H 5N4, Canada.,Institut de Pharmacologie de Sherbrooke, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Québec J1H 5N4, Canada
| | - Samuel Génier
- Département de Médecine, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Québec J1H 5N4, Canada.,Institut de Pharmacologie de Sherbrooke, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Québec J1H 5N4, Canada
| | - Jade Degrandmaison
- Département de Médecine, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Québec J1H 5N4, Canada.,Institut de Pharmacologie de Sherbrooke, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Québec J1H 5N4, Canada
| | - Samuel Picard
- Département de Médecine, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Québec J1H 5N4, Canada.,Institut de Pharmacologie de Sherbrooke, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Québec J1H 5N4, Canada.,Département de Pharmacologie-Physiologie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Québec J1H 5N4, Canada
| | - Louis Fréchette
- Département de Médecine, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Québec J1H 5N4, Canada.,Institut de Pharmacologie de Sherbrooke, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Québec J1H 5N4, Canada
| | - Steve Jean
- Département d'Anatomie et de Biologie Cellulaire, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Québec J1H 5N4, Canada
| | - Eric Marsault
- Institut de Pharmacologie de Sherbrooke, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Québec J1H 5N4, Canada.,Département de Pharmacologie-Physiologie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Québec J1H 5N4, Canada
| | - Jean-Luc Parent
- Département de Médecine, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Québec J1H 5N4, Canada .,Institut de Pharmacologie de Sherbrooke, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Québec J1H 5N4, Canada
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6
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Gillingham AK, Bertram J, Begum F, Munro S. In vivo identification of GTPase interactors by mitochondrial relocalization and proximity biotinylation. eLife 2019; 8:45916. [PMID: 31294692 PMCID: PMC6639074 DOI: 10.7554/elife.45916] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Accepted: 07/10/2019] [Indexed: 12/11/2022] Open
Abstract
The GTPases of the Ras superfamily regulate cell growth, membrane traffic and the cytoskeleton, and a wide range of diseases are caused by mutations in particular members. They function as switchable landmarks with the active GTP-bound form recruiting to the membrane a specific set of effector proteins. The GTPases are precisely controlled by regulators that promote acquisition of GTP (GEFs) or its hydrolysis to GDP (GAPs). We report here MitoID, a method for identifying effectors and regulators by performing in vivo proximity biotinylation with mitochondrially-localized forms of the GTPases. Applying this to 11 human Rab GTPases identified many known effectors and GAPs, as well as putative novel effectors, with examples of the latter validated for Rab2, Rab5, Rab9 and Rab11. MitoID can also efficiently identify effectors and GAPs of Rho and Ras family GTPases such as Cdc42, RhoA, Rheb, and N-Ras, and can identify GEFs by use of GDP-bound forms.
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Affiliation(s)
| | - Jessie Bertram
- MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
| | - Farida Begum
- MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
| | - Sean Munro
- MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
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7
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Pylypenko O, Hammich H, Yu IM, Houdusse A. Rab GTPases and their interacting protein partners: Structural insights into Rab functional diversity. Small GTPases 2018. [PMID: 28632484 DOI: 10.1080/215412481336191] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/23/2023] Open
Abstract
Rab molecular switches are key players in defining membrane identity and regulating intracellular trafficking events in eukaryotic cells. In spite of their global structural similarity, Rab-family members acquired particular features that allow them to perform specific cellular functions. The overall fold and local sequence conservations enable them to utilize a common machinery for prenylation and recycling; while individual Rab structural differences determine interactions with specific partners such as GEFs, GAPs and effector proteins. These interactions orchestrate the spatiotemporal regulation of Rab localization and their turning ON and OFF, leading to tightly controlled Rab-specific functionalities such as membrane composition modifications, recruitment of molecular motors for intracellular trafficking, or recruitment of scaffold proteins that mediate interactions with downstream partners, as well as actin cytoskeleton regulation. In this review we summarize structural information on Rab GTPases and their complexes with protein partners in the context of partner binding specificity and functional outcomes of their interactions in the cell.
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Affiliation(s)
- Olena Pylypenko
- a Structural Motility, Institut Curie , PSL Research University, CNRS, UMR 144 , Paris , France
| | - Hussein Hammich
- a Structural Motility, Institut Curie , PSL Research University, CNRS, UMR 144 , Paris , France
- b Sorbonne Universités , UPMC Univ Paris 06, Sorbonne Universités, IFD , Paris , France
| | - I-Mei Yu
- a Structural Motility, Institut Curie , PSL Research University, CNRS, UMR 144 , Paris , France
| | - Anne Houdusse
- a Structural Motility, Institut Curie , PSL Research University, CNRS, UMR 144 , Paris , France
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8
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New method of detecting hydrophobic interaction between C-terminal binding domain and biomacromolecules. J Biotechnol 2018; 265:101-108. [DOI: 10.1016/j.jbiotec.2017.11.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2017] [Revised: 10/16/2017] [Accepted: 11/17/2017] [Indexed: 01/29/2023]
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9
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Pylypenko O, Hammich H, Yu IM, Houdusse A. Rab GTPases and their interacting protein partners: Structural insights into Rab functional diversity. Small GTPases 2017. [PMID: 28632484 PMCID: PMC5902227 DOI: 10.1080/21541248.2017.1336191] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Rab molecular switches are key players in defining membrane identity and regulating intracellular trafficking events in eukaryotic cells. In spite of their global structural similarity, Rab-family members acquired particular features that allow them to perform specific cellular functions. The overall fold and local sequence conservations enable them to utilize a common machinery for prenylation and recycling; while individual Rab structural differences determine interactions with specific partners such as GEFs, GAPs and effector proteins. These interactions orchestrate the spatiotemporal regulation of Rab localization and their turning ON and OFF, leading to tightly controlled Rab-specific functionalities such as membrane composition modifications, recruitment of molecular motors for intracellular trafficking, or recruitment of scaffold proteins that mediate interactions with downstream partners, as well as actin cytoskeleton regulation. In this review we summarize structural information on Rab GTPases and their complexes with protein partners in the context of partner binding specificity and functional outcomes of their interactions in the cell.
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Affiliation(s)
- Olena Pylypenko
- a Structural Motility, Institut Curie , PSL Research University, CNRS, UMR 144 , Paris , France
| | - Hussein Hammich
- a Structural Motility, Institut Curie , PSL Research University, CNRS, UMR 144 , Paris , France.,b Sorbonne Universités , UPMC Univ Paris 06, Sorbonne Universités, IFD , Paris , France
| | - I-Mei Yu
- a Structural Motility, Institut Curie , PSL Research University, CNRS, UMR 144 , Paris , France
| | - Anne Houdusse
- a Structural Motility, Institut Curie , PSL Research University, CNRS, UMR 144 , Paris , France
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10
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Amick J, Ferguson SM. C9orf72: At the intersection of lysosome cell biology and neurodegenerative disease. Traffic 2017; 18:267-276. [PMID: 28266105 DOI: 10.1111/tra.12477] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Revised: 03/02/2017] [Accepted: 03/02/2017] [Indexed: 12/13/2022]
Abstract
The discovery that expansion of a hexanucleotide repeat within a noncoding region of the C9orf72 gene causes amyotrophic lateral sclerosis and frontotemporal dementia raised questions about C9orf72 protein function and potential disease relevance. The major predicted structural feature of the C9orf72 protein is a DENN (differentially expressed in normal and neoplastic cells) domain. As DENN domains are best characterized for regulation of specific Rab GTPases, it has been proposed that C9orf72 may also act through regulation of a GTPase target. Recent genetic and cell biological studies furthermore indicate that the C9orf72 protein functions at lysosomes as part of a larger complex that also contains the Smith-Magenis chromosome region 8 (SMCR8) and WD repeat-containing protein 41 (WDR41) proteins. An important role for C9orf72 at lysosomes is supported by defects in lysosome morphology and mTOR complex 1 (mTORC1) signaling arising from C9orf72 KO in diverse model systems. Collectively, these new findings define a C9orf72-containing protein complex and a lysosomal site of action as central to C9orf72 function and provide a foundation for the elucidation of direct physiological targets for C9orf72. Further elucidation of mechanisms whereby C9orf72 regulates lysosome function will help to determine how the reductions in C9orf72 expression levels that accompany hexanucleotide repeat expansions contribute to disease pathology.
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Affiliation(s)
- Joseph Amick
- Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut.,Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven, Connecticut
| | - Shawn M Ferguson
- Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut.,Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven, Connecticut
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11
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Abstract
Rab proteins are the major regulators of vesicular trafficking in eukaryotic cells. Their activity can be tightly controlled within cells: Regulated by guanine nucleotide exchange factors (GEFs) and GTPase activating proteins (GAPs), they switch between an active GTP-bound state and an inactive GDP-bound state, interacting with downstream effector proteins only in the active state. Additionally, they can bind to membranes via C-terminal prenylated cysteine residues and they can be solubilized and shuttled between membranes by chaperone-like molecules called GDP dissociation inhibitors (GDIs). In this review we give an overview of Rab proteins with a focus on the current understanding of their regulation by GEFs, GAPs and GDI.
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Affiliation(s)
- Matthias P Müller
- a Department of Structural Biochemistry , Max Planck Institute of Molecular Physiology , Dortmund , Germany
| | - Roger S Goody
- a Department of Structural Biochemistry , Max Planck Institute of Molecular Physiology , Dortmund , Germany
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