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Zhao X, Quintremil S, Rodriguez Castro ED, Cui H, Moraga D, Wang T, Vallee RB, Solmaz SR. Molecular mechanism for recognition of the cargo adapter Rab6 GTP by the dynein adapter BicD2. Life Sci Alliance 2024; 7:e202302430. [PMID: 38719748 PMCID: PMC11077774 DOI: 10.26508/lsa.202302430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 04/24/2024] [Accepted: 04/25/2024] [Indexed: 05/12/2024] Open
Abstract
Rab6 is a key modulator of protein secretion. The dynein adapter Bicaudal D2 (BicD2) recruits the motors cytoplasmic dynein and kinesin-1 to Rab6GTP-positive vesicles for transport; however, it is unknown how BicD2 recognizes Rab6. Here, we establish a structural model for recognition of Rab6GTP by BicD2, using structure prediction and mutagenesis. The binding site of BicD2 spans two regions of Rab6 that undergo structural changes upon the transition from the GDP- to GTP-bound state, and several hydrophobic interface residues are rearranged, explaining the increased affinity of the active GTP-bound state. Mutations of Rab6GTP that abolish binding to BicD2 also result in reduced co-migration of Rab6GTP/BicD2 in cells, validating our model. These mutations also severely diminished the motility of Rab6-positive vesicles in cells, highlighting the importance of the Rab6GTP/BicD2 interaction for overall motility of the multi-motor complex that contains both kinesin-1 and dynein. Our results provide insights into trafficking of secretory and Golgi-derived vesicles and will help devise therapies for diseases caused by BicD2 mutations, which selectively affect the affinity to Rab6 and other cargoes.
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Affiliation(s)
- Xiaoxin Zhao
- https://ror.org/008rmbt77 Department of Chemistry, Binghamton University, Binghamton, NY, USA
| | - Sebastian Quintremil
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY, USA
| | | | - Heying Cui
- https://ror.org/008rmbt77 Department of Chemistry, Binghamton University, Binghamton, NY, USA
| | - David Moraga
- https://ror.org/008rmbt77 Department of Chemistry, Binghamton University, Binghamton, NY, USA
| | - Tingyao Wang
- https://ror.org/008rmbt77 Department of Chemistry, Binghamton University, Binghamton, NY, USA
| | - Richard B Vallee
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY, USA
| | - Sozanne R Solmaz
- https://ror.org/008rmbt77 Department of Chemistry, Binghamton University, Binghamton, NY, USA
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2
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Xie S, Kuang W, Guo M, Yang F, Jin H, Chen X, Yi L, Huo C, Xu Z, Lin A, Liu W, Mao J, Shu Q, Zhou T. m6Am methyltransferase PCIF1 negatively regulates ciliation by inhibiting BICD2 expression. J Cell Biol 2024; 223:e202307002. [PMID: 38526325 DOI: 10.1083/jcb.202307002] [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: 07/07/2023] [Revised: 01/07/2024] [Accepted: 02/29/2024] [Indexed: 03/26/2024] Open
Abstract
N6, 2'-O-dimethyladenosine (m6Am) is a widespread RNA modification catalyzed by the methyltransferase PCIF1 (phosphorylated CTD interacting factor 1). Despite its prevalence, the biological functions of m6Am in RNA remain largely elusive. Here, we report a critical role of PCIF1-dependent m6Am RNA modification in ciliogenesis in RPE-1 cells. Our findings demonstrate that PCIF1 acts as a negative regulator of ciliation through its m6Am methyltransferase activity. A quantitative proteomic analysis identifies BICD2 as a downstream target of PCIF1, with PCIF1 depletion resulting in a significant increase in BICD2 levels. BICD2 depletion leads to a significant reduction in ciliation. Crucially, the ciliary phenotype in PCIF1-depleted cells is reversed upon BICD2 knockdown. Further investigations reveal that PCIF1 regulates BICD2 protein levels through its m6Am catalytic activity, which reduces the stability and translation efficiency of BICD2 mRNA. Single-base resolution LC-MS analysis identifies the m6Am site on BICD2 mRNA modified by PCIF1. These findings establish the essential involvement of PCIF1-dependent m6Am modification in ciliogenesis.
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Affiliation(s)
- Shanshan Xie
- Children's Hospital, National Clinical Research Center for Child Health, Zhejiang University School of Medicine, Hangzhou, China
| | - Wenjun Kuang
- International Institutes of Medicine, The Fourth Affiliated Hospital, Zhejiang University School of Medicine, Yiwu, China
| | - Mengzhe Guo
- School of Pharmacy, Xuzhou Medical University, Xuzhou, China
| | - Feng Yang
- Children's Hospital, National Clinical Research Center for Child Health, Zhejiang University School of Medicine, Hangzhou, China
| | - Hao Jin
- Department of Cell Biology, Zhejiang University School of Medicine, Hangzhou, China
| | - Xiying Chen
- Department of Cell Biology, Zhejiang University School of Medicine, Hangzhou, China
| | - Li Yi
- Department of Cell Biology, Zhejiang University School of Medicine, Hangzhou, China
| | - Chunxiao Huo
- Department of Cell Biology, Zhejiang University School of Medicine, Hangzhou, China
| | - Zhangqi Xu
- Children's Hospital, National Clinical Research Center for Child Health, Zhejiang University School of Medicine, Hangzhou, China
| | - Aifu Lin
- MOE Laboratory of Biosystem Homeostasis and Protection, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Wei Liu
- Metabolic Medicine Center, International Institutes of Medicine and the Fourth Affiliated Hospital, Zhejiang University School of Medicine, Yiwu, China
| | - Jianhua Mao
- Children's Hospital, National Clinical Research Center for Child Health, Zhejiang University School of Medicine, Hangzhou, China
| | - Qiang Shu
- Children's Hospital, National Clinical Research Center for Child Health, Zhejiang University School of Medicine, Hangzhou, China
| | - Tianhua Zhou
- Department of Cell Biology, Zhejiang University School of Medicine, Hangzhou, China
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3
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Xiong GJ, Sheng ZH. Presynaptic perspective: Axonal transport defects in neurodevelopmental disorders. J Cell Biol 2024; 223:e202401145. [PMID: 38568173 PMCID: PMC10988239 DOI: 10.1083/jcb.202401145] [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: 01/27/2024] [Revised: 03/20/2024] [Accepted: 03/21/2024] [Indexed: 04/05/2024] Open
Abstract
Disruption of synapse assembly and maturation leads to a broad spectrum of neurodevelopmental disorders. Presynaptic proteins are largely synthesized in the soma, where they are packaged into precursor vesicles and transported into distal axons to ensure precise assembly and maintenance of presynapses. Due to their morphological features, neurons face challenges in the delivery of presynaptic cargos to nascent boutons. Thus, targeted axonal transport is vital to build functional synapses. A growing number of mutations in genes encoding the transport machinery have been linked to neurodevelopmental disorders. Emerging lines of evidence have started to uncover presynaptic mechanisms underlying axonal transport defects, thus broadening the view of neurodevelopmental disorders beyond postsynaptic mechanisms. In this review, we discuss presynaptic perspectives of neurodevelopmental disorders by focusing on impaired axonal transport and disturbed assembly and maintenance of presynapses. We also discuss potential strategies for restoring axonal transport as an early therapeutic intervention.
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Affiliation(s)
- Gui-Jing Xiong
- Synaptic Function Section, The Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Zu-Hang Sheng
- Synaptic Function Section, The Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
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4
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Badieyan S, Lichon D, Andreas MP, Gillies JP, Peng W, Shi J, DeSantis ME, Aiken CR, Böcking T, Giessen TW, Campbell EM, Cianfrocco MA. HIV-1 binds dynein directly to hijack microtubule transport machinery. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.29.555335. [PMID: 37693451 PMCID: PMC10491134 DOI: 10.1101/2023.08.29.555335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
Viruses exploit host cytoskeletal elements and motor proteins for trafficking through the dense cytoplasm. Yet the molecular mechanism that describes how viruses connect to the motor machinery is unknown. Here, we demonstrate the first example of viral microtubule trafficking from purified components: HIV-1 hijacking microtubule transport machinery. We discover that HIV-1 directly binds to the retrograde microtubule-associated motor, dynein, and not via a cargo adaptor, as previously suggested. Moreover, we show that HIV-1 motility is supported by multiple, diverse dynein cargo adaptors as HIV-1 binds to dynein light and intermediate chains on dynein's tail. Further, we demonstrate that multiple dynein motors tethered to rigid cargoes, like HIV-1 capsids, display reduced motility, distinct from the behavior of multiple motors on membranous cargoes. Our results introduce a new model of viral trafficking wherein a pathogen opportunistically 'hijacks' the microtubule transport machinery for motility, enabling multiple transport pathways through the host cytoplasm.
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Affiliation(s)
| | - Drew Lichon
- Department of Microbiology and Immunology, Stritch School of Medicine, Loyola University Chicago, IL, USA
| | - Michael P Andreas
- Department of Biological Chemistry, Michigan Medicine, University of Michigan, Ann Arbor, MI, USA
| | - John P Gillies
- Department of Molecular, Cellular, and Developmental Biology, College of Literature, Sciences, and the Arts, University of Michigan, Ann Arbor, MI USA
| | - Wang Peng
- EMBL Australia Node in Single Molecule Science and ARC Centre of Excellence in Advanced Molecular Imaging, School of Medical Sciences, UNSW Sydney, Sydney, New South Wales, Australia
| | - Jiong Shi
- Department of Pathology, Microbiology, and Immunology, Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Morgan E DeSantis
- Department of Molecular, Cellular, and Developmental Biology, College of Literature, Sciences, and the Arts, University of Michigan, Ann Arbor, MI USA
| | - Christopher R Aiken
- Department of Pathology, Microbiology, and Immunology, Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Till Böcking
- EMBL Australia Node in Single Molecule Science and ARC Centre of Excellence in Advanced Molecular Imaging, School of Medical Sciences, UNSW Sydney, Sydney, New South Wales, Australia
| | - Tobias W Giessen
- Department of Biological Chemistry, Michigan Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Edward M Campbell
- Department of Microbiology and Immunology, Stritch School of Medicine, Loyola University Chicago, IL, USA
| | - Michael A Cianfrocco
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
- Department of Biological Chemistry, Michigan Medicine, University of Michigan, Ann Arbor, MI, USA
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5
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D'Souza AI, Grover R, Monzon GA, Santen L, Diez S. Vesicles driven by dynein and kinesin exhibit directional reversals without regulators. Nat Commun 2023; 14:7532. [PMID: 37985763 PMCID: PMC10662051 DOI: 10.1038/s41467-023-42605-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 10/16/2023] [Indexed: 11/22/2023] Open
Abstract
Intracellular vesicular transport along cytoskeletal filaments ensures targeted cargo delivery. Such transport is rarely unidirectional but rather bidirectional, with frequent directional reversals owing to the simultaneous presence of opposite-polarity motors. So far, it has been unclear whether such complex motility pattern results from the sole mechanical interplay between opposite-polarity motors or requires regulators. Here, we demonstrate that a minimal system, comprising purified Dynein-Dynactin-BICD2 (DDB) and kinesin-3 (KIF16B) attached to large unilamellar vesicles, faithfully reproduces in vivo cargo motility, including runs, pauses, and reversals. Remarkably, opposing motors do not affect vesicle velocity during runs. Our computational model reveals that the engagement of a small number of motors is pivotal for transitioning between runs and pauses. Taken together, our results suggest that motors bound to vesicular cargo transiently engage in a tug-of-war during pauses. Subsequently, stochastic motor attachment and detachment events can lead to directional reversals without the need for regulators.
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Affiliation(s)
- Ashwin I D'Souza
- B CUBE - Center for Molecular Bioengineering, TU Dresden, Dresden, Germany
| | - Rahul Grover
- B CUBE - Center for Molecular Bioengineering, TU Dresden, Dresden, Germany
| | - Gina A Monzon
- B CUBE - Center for Molecular Bioengineering, TU Dresden, Dresden, Germany
- Center for Biophysics, Department of Physics, Saarland University, Saarbrücken, Germany
| | - Ludger Santen
- Center for Biophysics, Department of Physics, Saarland University, Saarbrücken, Germany.
| | - Stefan Diez
- B CUBE - Center for Molecular Bioengineering, TU Dresden, Dresden, Germany.
- Cluster of Excellence Physics of Life, TU Dresden, Dresden, Germany.
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany.
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6
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Garrott SR, Gillies JP, Siva A, Little SR, El Jbeily R, DeSantis ME. Ndel1 disfavors dynein-dynactin-adaptor complex formation in two distinct ways. J Biol Chem 2023; 299:104735. [PMID: 37086789 PMCID: PMC10248797 DOI: 10.1016/j.jbc.2023.104735] [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: 01/26/2023] [Revised: 04/13/2023] [Accepted: 04/17/2023] [Indexed: 04/24/2023] Open
Abstract
Dynein is the primary minus-end-directed microtubule motor protein. To achieve activation, dynein binds to the dynactin complex and an adaptor to form the "activated dynein complex." The protein Lis1 aids activation by binding to dynein and promoting its association with dynactin and the adaptor. Ndel1 and its paralog Nde1 are dynein- and Lis1-binding proteins that help control dynein localization within the cell. Cell-based assays suggest that Ndel1-Nde1 also work with Lis1 to promote dynein activation, although the underlying mechanism is unclear. Using purified proteins and quantitative binding assays, here we found that the C-terminal region of Ndel1 contributes to dynein binding and negatively regulates binding to Lis1. Using single-molecule imaging and protein biochemistry, we observed that Ndel1 inhibits dynein activation in two distinct ways. First, Ndel1 disfavors the formation of the activated dynein complex. We found that phosphomimetic mutations in the C-terminal domain of Ndel1 increase its ability to inhibit dynein-dynactin-adaptor complex formation. Second, we observed that Ndel1 interacts with dynein and Lis1 simultaneously and sequesters Lis1 away from its dynein-binding site. In doing this, Ndel1 prevents Lis1-mediated dynein activation. Together, our work suggests that in vitro, Ndel1 is a negative regulator of dynein activation, which contrasts with cellular studies where Ndel1 promotes dynein activity. To reconcile our findings with previous work, we posit that Ndel1 functions to scaffold dynein and Lis1 together while keeping dynein in an inhibited state. We speculate that Ndel1 release can be triggered in cellular settings to allow for timed dynein activation.
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Affiliation(s)
- Sharon R Garrott
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA; Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan, USA
| | - John P Gillies
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Aravintha Siva
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Saffron R Little
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA; Program in Chemical Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Rita El Jbeily
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Morgan E DeSantis
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA; Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan, USA; Program in Chemical Biology, University of Michigan, Ann Arbor, Michigan, USA.
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7
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Gallisà-Suñé N, Sànchez-Fernàndez-de-Landa P, Zimmermann F, Serna M, Regué L, Paz J, Llorca O, Lüders J, Roig J. BICD2 phosphorylation regulates dynein function and centrosome separation in G2 and M. Nat Commun 2023; 14:2434. [PMID: 37105961 PMCID: PMC10140047 DOI: 10.1038/s41467-023-38116-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Accepted: 04/17/2023] [Indexed: 04/29/2023] Open
Abstract
The activity of dynein is regulated by a number of adaptors that mediate its interaction with dynactin, effectively activating the motor complex while also connecting it to different cargos. The regulation of adaptors is consequently central to dynein physiology but remains largely unexplored. We now describe that one of the best-known dynein adaptors, BICD2, is effectively activated through phosphorylation. In G2, phosphorylation of BICD2 by CDK1 promotes its interaction with PLK1. In turn, PLK1 phosphorylation of a single residue in the N-terminus of BICD2 results in a structural change that facilitates the interaction with dynein and dynactin, allowing the formation of active motor complexes. Moreover, modified BICD2 preferentially interacts with the nucleoporin RanBP2 once RanBP2 has been phosphorylated by CDK1. BICD2 phosphorylation is central for dynein recruitment to the nuclear envelope, centrosome tethering to the nucleus and centrosome separation in the G2 and M phases of the cell cycle. This work reveals adaptor activation through phosphorylation as crucial for the spatiotemporal regulation of dynein activity.
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Affiliation(s)
- Núria Gallisà-Suñé
- Department of Cells and Tissues, Molecular Biology Institute of Barcelona (IBMB-CSIC), Baldiri i Reixac 10-12, 08028, Barcelona, Spain
| | - Paula Sànchez-Fernàndez-de-Landa
- Department of Cells and Tissues, Molecular Biology Institute of Barcelona (IBMB-CSIC), Baldiri i Reixac 10-12, 08028, Barcelona, Spain
- Aging and Metabolism Programme, IRB Barcelona, Barcelona, Spain
| | - Fabian Zimmermann
- Mechanisms of Disease Programme, Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10-12, 08028, Barcelona, Spain
| | - Marina Serna
- Structural Biology Programme, Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, E-28029, Madrid, Spain
| | - Laura Regué
- Department of Cells and Tissues, Molecular Biology Institute of Barcelona (IBMB-CSIC), Baldiri i Reixac 10-12, 08028, Barcelona, Spain
| | - Joel Paz
- Mechanisms of Disease Programme, Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10-12, 08028, Barcelona, Spain
| | - Oscar Llorca
- Structural Biology Programme, Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, E-28029, Madrid, Spain
| | - Jens Lüders
- Mechanisms of Disease Programme, Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10-12, 08028, Barcelona, Spain
| | - Joan Roig
- Department of Cells and Tissues, Molecular Biology Institute of Barcelona (IBMB-CSIC), Baldiri i Reixac 10-12, 08028, Barcelona, Spain.
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8
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Unger A, Roos A, Gangfuß A, Hentschel A, Gläser D, Krause K, Doering K, Schara-Schmidt U, Hoffjan S, Vorgerd M, Güttsches AK. Microscopic and Biochemical Hallmarks of BICD2-Associated Muscle Pathology toward the Evaluation of Novel Variants. Int J Mol Sci 2023; 24:ijms24076808. [PMID: 37047781 PMCID: PMC10095373 DOI: 10.3390/ijms24076808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 04/02/2023] [Accepted: 04/03/2023] [Indexed: 04/08/2023] Open
Abstract
BICD2 variants have been linked to neurodegenerative disorders like spinal muscular atrophy with lower extremity predominance (SMALED2) or hereditary spastic paraplegia (HSP). Recently, mutations in BICD2 were implicated in myopathies. Here, we present one patient with a known and six patients with novel BICD2 missense variants, further characterizing the molecular landscape of this heterogenous neurological disorder. A total of seven patients were genotyped and phenotyped. Skeletal muscle biopsies were analyzed by histology, electron microscopy, and protein profiling to define pathological hallmarks and pathogenicity markers with consecutive validation using fluorescence microscopy. Clinical and MRI-features revealed a typical pattern of distal paresis of the lower extremities as characteristic features of a BICD2-associated disorder. Histological evaluation showed myopathic features of varying severity including fiber size variation, lipofibromatosis, and fiber splittings. Proteomic analysis with subsequent fluorescence analysis revealed an altered abundance and localization of thrombospondin-4 and biglycan. Our combined clinical, histopathological, and proteomic approaches provide new insights into the pathophysiology of BICD2-associated disorders, confirming a primary muscle cell vulnerability. In this context, biglycan and thrombospondin-4 have been identified, may serve as tissue pathogenicity markers, and might be linked to perturbed protein secretion based on an impaired vesicular transportation.
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Affiliation(s)
- Andreas Unger
- Department of Cardiovascular Medicine, Institute for Genetics of Heart Disease (IfGH), University Hospital Münster, 48149 Münster, Germany
- Institute of Physiology II, University of Münster, 48149 Münster, Germany
| | - Andreas Roos
- Department of Neurology, Heimer Institute for Muscle Research, University Hospital Bergmannsheil, Ruhr University Bochum, 44789 Bochum, Germany
- Department of Pediatric Neurology, Centre for Neuromuscular Disorders, Centre for Translational Neuro- and Behavioral Sciences, University Duisburg-Essen, 45122 Essen, Germany
- Children’s Hospital of Eastern Ontario Research Institute, Ottawa, ON K1H 8L1, Canada
| | - Andrea Gangfuß
- Children’s Hospital of Eastern Ontario Research Institute, Ottawa, ON K1H 8L1, Canada
| | - Andreas Hentschel
- Leibniz-Institut für Analytische Wissenschaften-ISAS-e.V., 44139 Dortmund, Germany
| | - Dieter Gläser
- Genetikum, Center for Human Genetics, 89231 Neu-Ulm, Germany
| | - Karsten Krause
- Department of Neurology, Heimer Institute for Muscle Research, University Hospital Bergmannsheil, Ruhr University Bochum, 44789 Bochum, Germany
| | - Kristina Doering
- Department of Human Genetics, Ruhr-University Bochum, 44801 Bochum, Germany
| | - Ulrike Schara-Schmidt
- Department of Pediatric Neurology, Centre for Neuromuscular Disorders, Centre for Translational Neuro- and Behavioral Sciences, University Duisburg-Essen, 45122 Essen, Germany
| | - Sabine Hoffjan
- Department of Human Genetics, Ruhr-University Bochum, 44801 Bochum, Germany
| | - Matthias Vorgerd
- Department of Neurology, Heimer Institute for Muscle Research, University Hospital Bergmannsheil, Ruhr University Bochum, 44789 Bochum, Germany
| | - Anne-Katrin Güttsches
- Department of Neurology, Heimer Institute for Muscle Research, University Hospital Bergmannsheil, Ruhr University Bochum, 44789 Bochum, Germany
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9
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Wong CH, Wingett SW, Qian C, Taliaferro JM, Ross-Thriepland D, Bullock SL. Genome-scale requirements for dynein-based trafficking revealed by a high-content arrayed CRISPR screen. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.01.530592. [PMID: 36909483 PMCID: PMC10002790 DOI: 10.1101/2023.03.01.530592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
Abstract
The cytoplasmic dynein-1 (dynein) motor plays a key role in cellular organisation by transporting a wide variety of cellular constituents towards the minus ends of microtubules. However, relatively little is known about how the biosynthesis, assembly and functional diversity of the motor is orchestrated. To address this issue, we have conducted an arrayed CRISPR loss-of-function screen in human cells using the distribution of dynein-tethered peroxisomes and early endosomes as readouts. From a guide RNA library targeting 18,253 genes, 195 validated hits were recovered and parsed into those impacting multiple dynein cargoes and those whose effects are restricted to a subset of cargoes. Clustering of high-dimensional phenotypic fingerprints generated from multiplexed images revealed co-functional genes involved in many cellular processes, including several candidate novel regulators of core dynein functions. Mechanistic analysis of one of these proteins, the RNA-binding protein SUGP1, provides evidence that it promotes cargo trafficking by sustaining functional expression of the dynein activator LIS1. Our dataset represents a rich source of new hypotheses for investigating microtubule-based transport, as well as several other aspects of cellular organisation that were captured by our high-content imaging.
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Affiliation(s)
- Chun Hao Wong
- Cell Biology Division, MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, UK
- Discovery Biology, Discovery Sciences, AstraZeneca, R&D, Cambridge, CB4 0WG, UK
- Current address: Wellcome Sanger Institute, Hinxton, Cambridge, CB10 1SA, UK
| | - Steven W. Wingett
- Cell Biology Division, MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, UK
| | - Chen Qian
- Quantitative Biology, Discovery Sciences, AstraZeneca, R&D, Cambridge, CB4 0WG, UK
| | - J. Matthew Taliaferro
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | | | - Simon L. Bullock
- Cell Biology Division, MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, UK
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10
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Abstract
The microtubule minus-end-directed motility of cytoplasmic dynein 1 (dynein), arguably the most complex and versatile cytoskeletal motor, is harnessed for diverse functions, such as long-range organelle transport in neuronal axons and spindle assembly in dividing cells. The versatility of dynein raises a number of intriguing questions, including how is dynein recruited to its diverse cargo, how is recruitment coupled to activation of the motor, how is motility regulated to meet different requirements for force production and how does dynein coordinate its activity with that of other microtubule-associated proteins (MAPs) present on the same cargo. Here, these questions will be discussed in the context of dynein at the kinetochore, the supramolecular protein structure that connects segregating chromosomes to spindle microtubules in dividing cells. As the first kinetochore-localized MAP described, dynein has intrigued cell biologists for more than three decades. The first part of this Review summarizes current knowledge about how kinetochore dynein contributes to efficient and accurate spindle assembly, and the second part describes the underlying molecular mechanisms and highlights emerging commonalities with dynein regulation at other subcellular sites.
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Affiliation(s)
- Reto Gassmann
- Instituto de Investigação e Inovação em Saúde - i3S, Universidade do Porto, 4200-135 Porto, Portugal.,Instituto de Biologia Molecular e Celular - IBMC, Universidade do Porto, 4200-135 Porto, Portugal
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11
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Garrott SR, Gillies JP, Siva A, Little SR, Jbeily REI, DeSantis ME. Ndel1 modulates dynein activation in two distinct ways. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.25.525437. [PMID: 36747695 PMCID: PMC9900795 DOI: 10.1101/2023.01.25.525437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Dynein is the primary minus-end-directed microtubule motor [1]. To achieve activation, dynein binds to the dynactin complex and an adaptor to form the "activated dynein complex" [2, 3]. The protein Lis1 aids activation by binding to dynein and promoting its association with dynactin and adaptor [4, 5]. Ndel1 and its orthologue Nde1 are dynein and Lis1 binding proteins that help control where dynein localizes within the cell [6]. Cell-based assays suggest that Ndel1/Nde1 also work with Lis1 to promote dynein activation, although the underlying mechanism is unclear [6]. Using purified proteins and quantitative binding assays, we found that Ndel1's C-terminal region contributes to binding to dynein and negatively regulates binding to Lis1. Using single-molecule imaging and protein biochemistry, we observed that Ndel1 inhibits dynein activation in two distinct ways. First, Ndel1 disfavors the formation of the activated dynein complex. We found that phosphomimetic mutations in Ndel1's C-terminal domain increase its ability to inhibit dynein-dynactin-adaptor complex formation. Second, we observed that Ndel1 interacts with dynein and Lis1 simultaneously and sequesters Lis1 away from its dynein binding site. In doing this, Ndel1 prevents Lis1-mediated dynein activation. Our work suggests that in vitro, Ndel1 is a negative regulator of dynein activation, which contrasts with cellular studies where Ndel1 promotes dynein activity. To reconcile our findings with previous work, we posit that Ndel1 functions to scaffold dynein and Lis1 together while keeping dynein in an inhibited state. We speculate that Ndel1 release can be triggered in cellular settings to allow for timed dynein activation.
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Affiliation(s)
- Sharon R Garrott
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Biological Chemistry, University of Michigan, Ann Arbor, MI 48109, USA
| | - John P Gillies
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Aravintha Siva
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Saffron R Little
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
- Program in Chemical Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Rita EI Jbeily
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Morgan E DeSantis
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Biological Chemistry, University of Michigan, Ann Arbor, MI 48109, USA
- Program in Chemical Biology, University of Michigan, Ann Arbor, MI 48109, USA
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12
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Lau CK. Reconstitution of Dynein/Dynactin Transport Using Recombinant Dynein. Methods Mol Biol 2023; 2623:135-156. [PMID: 36602684 DOI: 10.1007/978-1-0716-2958-1_9] [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] [Indexed: 01/06/2023]
Abstract
Cytoplasmic dynein-1 is activated by dynactin and a cargo adaptor for processive transport along microtubules. Dynein's motility can be visualized at the single-molecule level using total internal reflection fluorescence microscopy. Our understanding of the motile behavior of the dynein/dynactin complex has been aided by advances in recombinant expression, in particular for dynein. Here, I describe the purification of recombinant dynein and cargo adaptors, and endogenous dynactin and detail a protocol for the single-molecule motility assay. In this assay, microtubules are first immobilized on a coverslip. A fluorescently labeled dynein/dynactin/cargo adaptor complex is then added, allowing for the measurement of key motility parameters as the complex walks along the microtubule.
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Affiliation(s)
- Clinton K Lau
- Structural Studies Division, MRC Laboratory of Molecular Biology, Cambridge, UK.
- Department of Biochemistry, University of Oxford, Oxford, UK.
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13
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Liao P, Yuan Y, Liu Z, Hou X, Li W, Wen J, Zhang K, Jiao B, Shen L, Jiang H, Guo J, Tang B, Zhang Z, Hu Z, Wang J. Association of variants in the KIF1A gene with amyotrophic lateral sclerosis. Transl Neurodegener 2022; 11:46. [PMID: 36284339 PMCID: PMC9597953 DOI: 10.1186/s40035-022-00320-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Accepted: 10/10/2022] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Amyotrophic lateral sclerosis (ALS) is a devastating progressive neurodegenerative disease that affects neurons in the central nervous system and the spinal cord. As in many other neurodegenerative disorders, the genetic risk factors and pathogenesis of ALS involve dysregulation of cytoskeleton and neuronal transport. Notably, sensory and motor neuron diseases such as hereditary sensory and autonomic neuropathy type 2 (HSAN2) and spastic paraplegia 30 (SPG30) share several causative genes with ALS, as well as having common clinical phenotypes. KIF1A encodes a kinesin 3 motor that transports presynaptic vesicle precursors (SVPs) and dense core vesicles and has been reported as a causative gene for HSAN2 and SPG30. METHODS Here, we analyzed whole-exome sequencing data from 941 patients with ALS to investigate the genetic association of KIF1A with ALS. RESULTS We identified rare damage variants (RDVs) in the KIF1A gene associated with ALS and delineated the clinical characteristics of ALS patients with KIF1A RDVs. Clinically, these patients tended to exhibit sensory disturbance. Interestingly, the majority of these variants are located at the C-terminal cargo-binding region of the KIF1A protein. Functional examination revealed that the ALS-associated KIF1A variants located in the C-terminal region preferentially enhanced the binding of SVPs containing RAB3A, VAMP2, and synaptophysin. Expression of several disease-related KIF1A mutants in cultured mouse cortical neurons led to enhanced colocalization of RAB3A or VAMP2 with the KIF1A motor. CONCLUSIONS Our study highlighted the importance of KIF1A motor-mediated transport in the pathogenesis of ALS, indicating KIF1A as an important player in the oligogenic scenario of ALS.
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Affiliation(s)
- Panlin Liao
- Hunan Key Laboratory of Molecular Precision Medicine, Department of Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, 410008, China
| | - Yanchun Yuan
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, 410008, China
| | - Zhen Liu
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, 410008, China
| | - Xiaorong Hou
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, 410008, China
| | - Wanzhen Li
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, 410008, China
| | - Jin Wen
- Hunan Key Laboratory of Molecular Precision Medicine, Department of Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, 410008, China
| | - Kexuan Zhang
- Hunan Key Laboratory of Molecular Precision Medicine, Department of Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, 410008, China
| | - Bin Jiao
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, 410008, China
- National Clinical Research Center for Geriatric Diseases, Xiangya Hospital, Central South University, Changsha, 410008, China
- Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, 410008, China
- Center for Medical Genetics, School of Life Sciences, Central South University, Changsha, 410008, China
| | - Lu Shen
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, 410008, China
- National Clinical Research Center for Geriatric Diseases, Xiangya Hospital, Central South University, Changsha, 410008, China
- Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, 410008, China
- Center for Medical Genetics, School of Life Sciences, Central South University, Changsha, 410008, China
- Engineering Research Center of Hunan Province in Cognitive Impairment Disorders, Central South University, Changsha, 410008, China
- Hunan International Scientific and Technological Cooperation Base of Neurodegenerative and Neurogenetic Diseases, Changsha, 410008, China
| | - Hong Jiang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, 410008, China
- National Clinical Research Center for Geriatric Diseases, Xiangya Hospital, Central South University, Changsha, 410008, China
- Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, 410008, China
- Center for Medical Genetics, School of Life Sciences, Central South University, Changsha, 410008, China
| | - Jifeng Guo
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, 410008, China
- National Clinical Research Center for Geriatric Diseases, Xiangya Hospital, Central South University, Changsha, 410008, China
- Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, 410008, China
- Center for Medical Genetics, School of Life Sciences, Central South University, Changsha, 410008, China
| | - Beisha Tang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, 410008, China
- National Clinical Research Center for Geriatric Diseases, Xiangya Hospital, Central South University, Changsha, 410008, China
- Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, 410008, China
- Center for Medical Genetics, School of Life Sciences, Central South University, Changsha, 410008, China
| | - Zhuohua Zhang
- Hunan Key Laboratory of Molecular Precision Medicine, Department of Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, 410008, China
- National Clinical Research Center for Geriatric Diseases, Xiangya Hospital, Central South University, Changsha, 410008, China
- Center for Medical Genetics, School of Life Sciences, Central South University, Changsha, 410008, China
| | - Zhonghua Hu
- Hunan Key Laboratory of Molecular Precision Medicine, Department of Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, 410008, China.
- National Clinical Research Center for Geriatric Diseases, Xiangya Hospital, Central South University, Changsha, 410008, China.
- Center for Medical Genetics, School of Life Sciences, Central South University, Changsha, 410008, China.
- Hunan Provincial Clinical Research Center for Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, 410008, China.
- Hunan Key Laboratory of Animal Models for Human Diseases, School of Life Sciences, Central South University, Changsha, 410008, China.
| | - Junling Wang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, 410008, China.
- National Clinical Research Center for Geriatric Diseases, Xiangya Hospital, Central South University, Changsha, 410008, China.
- Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, 410008, China.
- Center for Medical Genetics, School of Life Sciences, Central South University, Changsha, 410008, China.
- Engineering Research Center of Hunan Province in Cognitive Impairment Disorders, Central South University, Changsha, 410008, China.
- Hunan International Scientific and Technological Cooperation Base of Neurodegenerative and Neurogenetic Diseases, Changsha, 410008, China.
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14
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Stevens DA, Beierschmitt C, Mahesula S, Corley MR, Salogiannis J, Tsu BV, Cao B, Ryan AP, Hakozawki H, Reck-Peterson SL, Daugherty MD. Antiviral function and viral antagonism of the rapidly evolving dynein activating adaptor NINL. eLife 2022; 11:e81606. [PMID: 36222652 PMCID: PMC9651953 DOI: 10.7554/elife.81606] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Accepted: 10/11/2022] [Indexed: 11/13/2022] Open
Abstract
Viruses interact with the intracellular transport machinery to promote viral replication. Such host-virus interactions can drive host gene adaptation, leaving signatures of pathogen-driven evolution in host genomes. Here, we leverage these genetic signatures to identify the dynein activating adaptor, ninein-like (NINL), as a critical component in the antiviral innate immune response and as a target of viral antagonism. Unique among genes encoding components of active dynein complexes, NINL has evolved under recurrent positive (diversifying) selection, particularly in its carboxy-terminal cargo-binding region. Consistent with a role for NINL in host immunity, we demonstrate that NINL knockout cells exhibit an impaired response to interferon, resulting in increased permissiveness to viral replication. Moreover, we show that proteases encoded by diverse picornaviruses and coronaviruses cleave and disrupt NINL function in a host- and virus-specific manner. Our work reveals the importance of NINL in the antiviral response and the utility of using signatures of host-virus genetic conflicts to uncover new components of antiviral immunity and targets of viral antagonism.
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Affiliation(s)
- Donté Alexander Stevens
- Department of Cellular and Molecular Medicine, University of California, San DiegoLa JollaUnited States
| | | | - Swetha Mahesula
- Department of Cellular and Molecular Medicine, University of California, San DiegoLa JollaUnited States
- Howard Hughes Medical InstituteChevy ChaseUnited States
| | - Miles R Corley
- Department of Molecular Biology, University of California, San DiegoLa JollaUnited States
| | - John Salogiannis
- Department of Cellular and Molecular Medicine, University of California, San DiegoLa JollaUnited States
| | - Brian V Tsu
- Department of Molecular Biology, University of California, San DiegoLa JollaUnited States
| | - Bryant Cao
- Department of Molecular Biology, University of California, San DiegoLa JollaUnited States
| | - Andrew P Ryan
- Department of Molecular Biology, University of California, San DiegoLa JollaUnited States
| | - Hiroyuki Hakozawki
- Nikon Imaging Center at UC San Diego, University of California, San DiegoSan DiegoUnited States
| | - Samara L Reck-Peterson
- Department of Cellular and Molecular Medicine, University of California, San DiegoLa JollaUnited States
- Howard Hughes Medical InstituteChevy ChaseUnited States
- Department of Cell and Developmental Biology, University of California, San DiegoLa JollaUnited States
| | - Matthew D Daugherty
- Department of Molecular Biology, University of California, San DiegoLa JollaUnited States
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15
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In vitro characterization of the full-length human dynein-1 cargo adaptor BicD2. Structure 2022; 30:1470-1478.e3. [PMID: 36150379 DOI: 10.1016/j.str.2022.08.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 07/07/2022] [Accepted: 08/29/2022] [Indexed: 11/22/2022]
Abstract
Cargo adaptors are crucial in coupling motor proteins with their respective cargos and regulatory proteins. BicD2 is a prominent example within the cargo adaptor family. BicD2 is able to recruit the microtubule motor dynein to RNA, viral particles, and nuclei. The BicD2-mediated interaction between the nucleus and dynein is implicated in mitosis, interkinetic nuclear migration (INM) in radial glial progenitor cells, and neuron precursor migration during embryonic neocortex development. In vitro studies involving full-length cargo adaptors are difficult to perform due to the hydrophobic character, low-expression levels, and intrinsic flexibility of cargo adaptors. Here, we report the recombinant production of full-length human BicD2 and confirm its biochemical activity by interaction studies with RanBP2. We also describe pH-dependent conformational changes of BicD2 using cryoelectron microscopy (cryo-EM), template-free structure predictions, and biophysical tools. Our results will help define the biochemical parameters for the in vitro reconstitution of higher-order BicD2 protein complexes.
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16
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Brault J, Bardin S, Lampic M, Carpentieri JA, Coquand L, Penisson M, Lachuer H, Victoria GS, Baloul S, El Marjou F, Boncompain G, Miserey‐Lenkei S, Belvindrah R, Fraisier V, Francis F, Perez F, Goud B, Baffet AD. RAB6
and dynein drive
post‐Golgi
apical transport to prevent neuronal progenitor delamination. EMBO Rep 2022; 23:e54605. [PMID: 35979738 PMCID: PMC9535803 DOI: 10.15252/embr.202254605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 07/18/2022] [Accepted: 07/25/2022] [Indexed: 12/03/2022] Open
Abstract
Radial glial (RG) cells are the neural stem cells of the developing neocortex. Apical RG (aRG) cells can delaminate to generate basal RG (bRG) cells, a cell type associated with human brain expansion. Here, we report that aRG delamination is regulated by the post‐Golgi secretory pathway. Using in situ subcellular live imaging, we show that post‐Golgi transport of RAB6+ vesicles occurs toward the minus ends of microtubules and depends on dynein. We demonstrate that the apical determinant Crumbs3 (CRB3) is also transported by dynein. Double knockout of RAB6A/A' and RAB6B impairs apical localization of CRB3 and induces a retraction of aRG cell apical process, leading to delamination and ectopic division. These defects are phenocopied by knockout of the dynein activator LIS1. Overall, our results identify a RAB6‐dynein‐LIS1 complex for Golgi to apical surface transport in aRG cells, and highlights the role of this pathway in the maintenance of neuroepithelial integrity.
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Affiliation(s)
| | - Sabine Bardin
- Institut Curie PSL Research University, CNRS UMR144 Paris France
| | - Marusa Lampic
- Institut Curie PSL Research University, CNRS UMR144 Paris France
| | | | - Laure Coquand
- Institut Curie PSL Research University, CNRS UMR144 Paris France
- Sorbonne University Paris France
| | - Maxime Penisson
- Sorbonne University Paris France
- INSERM UMR‐S 1270 Paris France
- Institut du Fer à Moulin Paris France
| | - Hugo Lachuer
- Institut Curie PSL Research University, CNRS UMR144 Paris France
| | | | - Sarah Baloul
- Institut Curie PSL Research University, CNRS UMR144 Paris France
| | - Fatima El Marjou
- Institut Curie PSL Research University, CNRS UMR144 Paris France
| | | | | | - Richard Belvindrah
- Sorbonne University Paris France
- INSERM UMR‐S 1270 Paris France
- Institut du Fer à Moulin Paris France
| | - Vincent Fraisier
- UMR 144‐Cell and Tissue Imaging Facility (PICT‐IBiSA) CNRS‐Institut Curie Paris France
| | - Fiona Francis
- Sorbonne University Paris France
- INSERM UMR‐S 1270 Paris France
- Institut du Fer à Moulin Paris France
| | - Franck Perez
- Institut Curie PSL Research University, CNRS UMR144 Paris France
| | - Bruno Goud
- Institut Curie PSL Research University, CNRS UMR144 Paris France
| | - Alexandre D Baffet
- Institut Curie PSL Research University, CNRS UMR144 Paris France
- Institut National de la Santé et de la Recherche Médicale (INSERM) Paris France
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17
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Agrawal R, Gillies JP, Zang JL, Zhang J, Garrott SR, Shibuya H, Nandakumar J, DeSantis ME. The KASH5 protein involved in meiotic chromosomal movements is a novel dynein activating adaptor. eLife 2022; 11:78201. [PMID: 35703493 PMCID: PMC9242646 DOI: 10.7554/elife.78201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Accepted: 06/14/2022] [Indexed: 11/30/2022] Open
Abstract
Dynein harnesses ATP hydrolysis to move cargo on microtubules in multiple biological contexts. Dynein meets a unique challenge in meiosis by moving chromosomes tethered to the nuclear envelope to facilitate homolog pairing essential for gametogenesis. Though processive dynein motility requires binding to an activating adaptor, the identity of the activating adaptor required for dynein to move meiotic chromosomes is unknown. We show that the meiosis-specific nuclear-envelope protein KASH5 is a dynein activating adaptor: KASH5 directly binds dynein using a mechanism conserved among activating adaptors and converts dynein into a processive motor. We map the dynein-binding surface of KASH5, identifying mutations that abrogate dynein binding in vitro and disrupt recruitment of the dynein machinery to the nuclear envelope in cultured cells and mouse spermatocytes in vivo. Our study identifies KASH5 as the first transmembrane dynein activating adaptor and provides molecular insights into how it activates dynein during meiosis.
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Affiliation(s)
- Ritvija Agrawal
- Department of Molecular, Cellular and Developmental Biology, University of Michigan-Ann Arbor, Ann Arbor, United States
| | - John P Gillies
- Department of Molecular, Cellular and Developmental Biology, University of Michigan-Ann Arbor, Ann Arbor, United States
| | - Juliana L Zang
- Department of Molecular, Cellular and Developmental Biology, University of Michigan-Ann Arbor, Ann Arbor, United States
| | - Jingjing Zhang
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Sharon R Garrott
- Department of Molecular, Cellular and Developmental Biology, University of Michigan-Ann Arbor, Ann Arbor, United States
| | - Hiroki Shibuya
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Jayakrishnan Nandakumar
- Department of Molecular, Cellular and Developmental Biology, University of Michigan-Ann Arbor, Ann Arbor, United States
| | - Morgan E DeSantis
- Department of Molecular, Cellular and Developmental Biology, University of Michigan-Ann Arbor, Ann Arbor, United States
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18
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Nakano J, Chiba K, Niwa S. An ALS-associated KIF5A mutant forms oligomers and aggregates and induces neuronal toxicity. Genes Cells 2022; 27:421-435. [PMID: 35430760 PMCID: PMC9322661 DOI: 10.1111/gtc.12936] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 04/09/2022] [Accepted: 04/10/2022] [Indexed: 11/30/2022]
Abstract
KIF5A is a kinesin superfamily motor protein that transports various cargos in neurons. Mutations in Kif5a cause familial amyotrophic lateral sclerosis (ALS). These ALS mutations are in the intron of Kif5a and induce mis-splicing of KIF5A mRNA, leading to splicing out of exon 27, which in human KIF5A encodes the cargo-binding tail domain of KIF5A. Therefore, it has been suggested that ALS is caused by loss of function of KIF5A. However, the precise mechanisms regarding how mutations in KIF5A cause ALS remain unclear. Here, we show that an ALS-associated mutant of KIF5A, KIF5A(Δexon27), is predisposed to form oligomers and aggregates in cultured mouse cell lines. Interestingly, purified KIF5A(Δexon27) oligomers showed more active movement on microtubules than wild-type KIF5A in vitro. Purified KIF5A(∆exon27) was prone to form aggregates in vitro. Moreover, KIF5A(Δexon27)-expressing Caenorhabditis elegans neurons showed morphological defects. These data collectively suggest that ALS-associated mutations of KIF5A are toxic gain-of-function mutations rather than simple loss-of-function mutations.
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Affiliation(s)
- Juri Nakano
- Graduate School of Life SciencesTohoku UniversitySendaiJapan
| | - Kyoko Chiba
- Frontier Research Institute for Interdisciplinary Sciences (FRIS)Tohoku UniversitySendaiMiyagiJapan
| | - Shinsuke Niwa
- Graduate School of Life SciencesTohoku UniversitySendaiJapan
- Frontier Research Institute for Interdisciplinary Sciences (FRIS)Tohoku UniversitySendaiMiyagiJapan
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19
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Keren-Kaplan T, Sarić A, Ghosh S, Williamson CD, Jia R, Li Y, Bonifacino JS. RUFY3 and RUFY4 are ARL8 effectors that promote coupling of endolysosomes to dynein-dynactin. Nat Commun 2022; 13:1506. [PMID: 35314674 PMCID: PMC8938451 DOI: 10.1038/s41467-022-28952-y] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 02/18/2022] [Indexed: 11/10/2022] Open
Abstract
The small GTPase ARL8 associates with endolysosomes, leading to the recruitment of several effectors that couple endolysosomes to kinesins for anterograde transport along microtubules, and to tethering factors for eventual fusion with other organelles. Herein we report the identification of the RUN- and FYVE-domain-containing proteins RUFY3 and RUFY4 as ARL8 effectors that promote coupling of endolysosomes to dynein-dynactin for retrograde transport along microtubules. Using various methodologies, we find that RUFY3 and RUFY4 interact with both GTP-bound ARL8 and dynein-dynactin. In addition, we show that RUFY3 and RUFY4 promote concentration of endolysosomes in the juxtanuclear area of non-neuronal cells, and drive redistribution of endolysosomes from the axon to the soma in hippocampal neurons. The function of RUFY3 in retrograde transport contributes to the juxtanuclear redistribution of endolysosomes upon cytosol alkalinization. These studies thus identify RUFY3 and RUFY4 as ARL8-dependent, dynein-dynactin adaptors or regulators, and highlight the role of ARL8 in the control of both anterograde and retrograde endolysosome transport. Organellar transport is carefully regulated, and endolysosome localized ARL8 is important for kinesin recruitment and anterograde movement. Here, the authors show that RUFY3 and RUFY4 promote retrograde transport of endolysosomes by mediating interaction of ARL8 with dynein-dynactin.
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20
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Gibson JM, Cui H, Ali MY, Zhao X, Debler EW, Zhao J, Trybus KM, Solmaz SR, Wang C. Coil-to-α-helix transition at the Nup358-BicD2 interface activates BicD2 for dynein recruitment. eLife 2022; 11:74714. [PMID: 35229716 PMCID: PMC8956292 DOI: 10.7554/elife.74714] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Accepted: 02/28/2022] [Indexed: 11/13/2022] Open
Abstract
Nup358, a protein of the nuclear pore complex, facilitates a nuclear positioning pathway that is essential for many biological processes, including neuromuscular and brain development. Nup358 interacts with the dynein adaptor Bicaudal D2 (BicD2), which in turn recruits the dynein machinery to position the nucleus. However, the molecular mechanisms of the Nup358/BicD2 interaction and the activation of transport remain poorly understood. Here for the first time, we show that a minimal Nup358 domain activates dynein/dynactin/BicD2 for processive motility on microtubules. Using nuclear magnetic resonance titration and chemical exchange saturation transfer, mutagenesis, and circular dichroism spectroscopy, a Nup358 α-helix encompassing residues 2162–2184 was identified, which transitioned from a random coil to an α-helical conformation upon BicD2 binding and formed the core of the Nup358-BicD2 interface. Mutations in this region of Nup358 decreased the Nup358/BicD2 interaction, resulting in decreased dynein recruitment and impaired motility. BicD2 thus recognizes Nup358 through a ‘cargo recognition α-helix,’ a structural feature that may stabilize BicD2 in its activated state and promote processive dynein motility.
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Affiliation(s)
- James M Gibson
- Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, United States
| | - Heying Cui
- Department of Chemistry, Binghamton University, Binghamton, United States
| | - M Yusuf Ali
- Department of Molecular Physiology and Biophysics, University of Vermont, Burlington, United States
| | - Xioaxin Zhao
- Department of Biological Sciences, Binghamton University, Binghamton, United States
| | - Erik W Debler
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, United States
| | - Jing Zhao
- Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, United States
| | - Kathleen M Trybus
- Department of Molecular Physiology and Biophysics, University of Vermont, Burlington, United States
| | - Sozanne R Solmaz
- Department of Chemistry, Binghamton University, Binghamton, United States
| | - Chunyu Wang
- Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, United States
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21
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Neurogenic arthrogryposis and the power of phenotyping. Neuromuscul Disord 2021; 31:1062-1069. [PMID: 34736627 DOI: 10.1016/j.nmd.2021.07.399] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 07/22/2021] [Accepted: 07/27/2021] [Indexed: 11/23/2022]
Abstract
In this article we review the commonest cause of neurogenic arthrogryposis, termed Spinal Muscular Atrophy Lower Extremity Dominant (SMALED), due to variants in DYNC1H1 and BICD2. We discuss the characteristic clinical and radiological phenotype of this disorder and how this has facilitated the identification of the genetic cause of SMALED2. We also review the similarities and differences between the human SMALED phenotype and mouse models and how this has informed our understanding of the potential mechanisms governing motor neuron loss in these disorders.
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22
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Cui H, Ali MY, Goyal P, Zhang K, Loh JY, Trybus KM, Solmaz SR. Coiled-coil registry shifts in the F684I mutant of Bicaudal D result in cargo-independent activation of dynein motility. Traffic 2021; 21:463-478. [PMID: 32378283 DOI: 10.1111/tra.12734] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Revised: 04/29/2020] [Accepted: 05/01/2020] [Indexed: 11/28/2022]
Abstract
The dynein adaptor Drosophila Bicaudal D (BicD) is auto-inhibited and activates dynein motility only after cargo is bound, but the underlying mechanism is elusive. In contrast, we show that the full-length BicD/F684I mutant activates dynein processivity even in the absence of cargo. Our X-ray structure of the C-terminal domain of the BicD/F684I mutant reveals a coiled-coil registry shift; in the N-terminal region, the two helices of the homodimer are aligned, whereas they are vertically shifted in the wild-type. One chain is partially disordered and this structural flexibility is confirmed by computations, which reveal that the mutant transitions back and forth between the two registries. We propose that a coiled-coil registry shift upon cargo-binding activates BicD for dynein recruitment. Moreover, the human homolog BicD2/F743I exhibits diminished binding of cargo adaptor Nup358, implying that a coiled-coil registry shift may be a mechanism to modulate cargo selection for BicD2-dependent transport pathways.
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Affiliation(s)
- Heying Cui
- Department of Chemistry, State University of New York at Binghamton, Binghamton, New York, USA
| | - M Yusuf Ali
- Department of Molecular Physiology and Biophysics, University of Vermont, Burlington, Vermont, USA
| | - Puja Goyal
- Department of Chemistry, State University of New York at Binghamton, Binghamton, New York, USA
| | - Kaiqi Zhang
- Department of Chemistry, State University of New York at Binghamton, Binghamton, New York, USA
| | - Jia Ying Loh
- Department of Chemistry, State University of New York at Binghamton, Binghamton, New York, USA
| | - Kathleen M Trybus
- Department of Molecular Physiology and Biophysics, University of Vermont, Burlington, Vermont, USA
| | - Sozanne R Solmaz
- Department of Chemistry, State University of New York at Binghamton, Binghamton, New York, USA
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23
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Hayashi K, Miyamoto MG, Niwa S. Effects of dynein inhibitor on the number of motor proteins transporting synaptic cargos. Biophys J 2021; 120:1605-1614. [PMID: 33617835 PMCID: PMC8204214 DOI: 10.1016/j.bpj.2021.02.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 02/02/2021] [Accepted: 02/08/2021] [Indexed: 11/27/2022] Open
Abstract
Synaptic cargo transport by kinesin and dynein in hippocampal neurons was investigated by noninvasively measuring the transport force based on nonequilibrium statistical mechanics. Although direct physical measurements such as force measurement using optical tweezers are difficult in an intracellular environment, the noninvasive estimations enabled enumerating force-producing units (FPUs) carrying a cargo comprising the motor proteins generating force. The number of FPUs served as a barometer for stable and long-distance transport by multiple motors, which was then used to quantify the extent of damage to axonal transport by dynarrestin, a dynein inhibitor. We found that dynarrestin decreased the FPU for retrograde transport more than for anterograde transport. This result indicates the applicability of the noninvasive force measurements. In the future, these measurements may be used to quantify damage to axonal transport resulting from neuronal diseases, including Alzheimer's, Parkinson's, and Huntington's diseases.
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Affiliation(s)
- Kumiko Hayashi
- Department of Applied Physics, Graduate School of Engineering, Tohoku University, Sendai, Japan.
| | - Miki G Miyamoto
- Department of Applied Physics, Graduate School of Engineering, Tohoku University, Sendai, Japan
| | - Shinsuke Niwa
- Frontier Research Institute for Interdisciplinary Sciences and Graduate School of Life Science, Tohoku University, Sendai, Japan
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24
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Spriggs CC, Badieyan S, Verhey KJ, Cianfrocco MA, Tsai B. Golgi-associated BICD adaptors couple ER membrane penetration and disassembly of a viral cargo. J Cell Biol 2021; 219:151622. [PMID: 32259203 PMCID: PMC7199864 DOI: 10.1083/jcb.201908099] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 12/04/2019] [Accepted: 02/21/2020] [Indexed: 12/22/2022] Open
Abstract
During entry, viruses must navigate through the host endomembrane system, penetrate cellular membranes, and undergo capsid disassembly to reach an intracellular destination that supports infection. How these events are coordinated is unclear. Here, we reveal an unexpected function of a cellular motor adaptor that coordinates virus membrane penetration and disassembly. Polyomavirus SV40 traffics to the endoplasmic reticulum (ER) and penetrates a virus-induced structure in the ER membrane called “focus” to reach the cytosol, where it disassembles before nuclear entry to promote infection. We now demonstrate that the ER focus is constructed proximal to the Golgi-associated BICD2 and BICDR1 dynein motor adaptors; this juxtaposition enables the adaptors to directly bind to and disassemble SV40 upon arrival to the cytosol. Our findings demonstrate that positioning of the virus membrane penetration site couples two decisive infection events, cytosol arrival and disassembly, and suggest cargo remodeling as a novel function of dynein adaptors.
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Affiliation(s)
- Chelsey C Spriggs
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI
| | - Somayesadat Badieyan
- Department of Biological Chemistry and the Life Sciences Institute, University of Michigan, Ann Arbor, MI
| | - Kristen J Verhey
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI
| | - Michael A Cianfrocco
- Department of Biological Chemistry and the Life Sciences Institute, University of Michigan, Ann Arbor, MI
| | - Billy Tsai
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI
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25
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Kesisova IA, Robinson BP, Spiliotis ET. A septin GTPase scaffold of dynein-dynactin motors triggers retrograde lysosome transport. J Cell Biol 2021; 220:211663. [PMID: 33416861 PMCID: PMC7802366 DOI: 10.1083/jcb.202005219] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 11/22/2020] [Accepted: 12/09/2020] [Indexed: 12/12/2022] Open
Abstract
The metabolic and signaling functions of lysosomes depend on their intracellular positioning and trafficking, but the underlying mechanisms are little understood. Here, we have discovered a novel septin GTPase-based mechanism for retrograde lysosome transport. We found that septin 9 (SEPT9) associates with lysosomes, promoting the perinuclear localization of lysosomes in a Rab7-independent manner. SEPT9 targeting to mitochondria and peroxisomes is sufficient to recruit dynein and cause perinuclear clustering. We show that SEPT9 interacts with both dynein and dynactin through its GTPase domain and N-terminal extension, respectively. Strikingly, SEPT9 associates preferentially with the dynein intermediate chain (DIC) in its GDP-bound state, which favors dimerization and assembly into septin multimers. In response to oxidative cell stress induced by arsenite, SEPT9 localization to lysosomes is enhanced, promoting the perinuclear clustering of lysosomes. We posit that septins function as GDP-activated scaffolds for the cooperative assembly of dynein-dynactin, providing an alternative mechanism of retrograde lysosome transport at steady state and during cellular adaptation to stress.
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26
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Keren-Kaplan T, Bonifacino JS. ARL8 Relieves SKIP Autoinhibition to Enable Coupling of Lysosomes to Kinesin-1. Curr Biol 2020; 31:540-554.e5. [PMID: 33232665 DOI: 10.1016/j.cub.2020.10.071] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 09/16/2020] [Accepted: 10/23/2020] [Indexed: 01/24/2023]
Abstract
Long-range movement of organelles within the cytoplasm relies on coupling to microtubule motors, a process that is often mediated by adaptor proteins. In many cases, this coupling involves organelle- or adaptor-induced activation of the microtubule motors by conformational reversal of an autoinhibited state. Herein, we show that a similar regulatory mechanism operates for an adaptor protein named SKIP (also known as PLEKHM2). SKIP binds to the small guanosine triphosphatase (GTPase) ARL8 on the lysosomal membrane to couple lysosomes to the anterograde microtubule motor kinesin-1. Structure-function analyses of SKIP reveal that the C-terminal region comprising three pleckstrin homology (PH) domains interacts with the N-terminal region comprising ARL8- and kinesin-1-binding sites. This interaction inhibits coupling of lysosomes to kinesin-1 and, consequently, lysosome movement toward the cell periphery. We also find that ARL8 does not just recruit SKIP to the lysosomal membrane but also relieves SKIP autoinhibition, promoting kinesin-1-driven, anterograde lysosome transport. Finally, our analyses show that the largely disordered middle region of SKIP mediates self-association and that this self-association enhances the interaction of SKIP with kinesin-1. These findings indicate that SKIP is not just a passive connector of lysosome-bound ARL8 to kinesin-1 but is itself subject to intra- and inter-molecular interactions that regulate its function. We anticipate that similar organelle- or GTPase-induced conformational changes could regulate the activity of other kinesin adaptors.
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Affiliation(s)
- Tal Keren-Kaplan
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Juan S Bonifacino
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
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27
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Tsai MH, Cheng HY, Nian FS, Liu C, Chao NH, Chiang KL, Chen SF, Tsai JW. Impairment in dynein-mediated nuclear translocation by BICD2 C-terminal truncation leads to neuronal migration defect and human brain malformation. Acta Neuropathol Commun 2020; 8:106. [PMID: 32665036 PMCID: PMC7362644 DOI: 10.1186/s40478-020-00971-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 06/19/2020] [Indexed: 02/06/2023] Open
Abstract
During brain development, the nucleus of migrating neurons follows the centrosome and translocates into the leading process. Defects in these migratory events, which affect neuronal migration, cause lissencephaly and other neurodevelopmental disorders. However, the mechanism of nuclear translocation remains elusive. Using whole exome sequencing (WES), we identified a novel nonsense BICD2 variant p.(Lys775Ter) (K775X) from a lissencephaly patient. Interestingly, most BICD2 missense variants have been associated with human spinal muscular atrophy (SMA) without obvious brain malformations. By in utero electroporation, we showed that BicD2 knockdown in mouse embryos inhibited neuronal migration. Surprisingly, we observed severe blockage of neuronal migration in cells overexpressing K775X but not in those expressing wild-type BicD2 or SMA-associated missense variants. The centrosome of the mutant was, on average, positioned farther away from the nucleus, indicating a failure in nuclear translocation without affecting the centrosome movement. Furthermore, BicD2 localized at the nuclear envelope (NE) through its interaction with NE protein Nesprin-2. K775X variant disrupted this interaction and further interrupted the NE recruitment of BicD2 and dynein. Remarkably, fusion of BicD2-K775X with NE-localizing domain KASH resumed neuronal migration. Our results underscore impaired nuclear translocation during neuronal migration as an important pathomechanism of lissencephaly.
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28
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Expression of ArfGAP3 in Vaginal Anterior Wall of Patients With Pelvic Floor Organ Prolapse in Pelvic Organ Prolapse and Non-Pelvic Organ Prolapse Patients. Female Pelvic Med Reconstr Surg 2020; 27:e64-e69. [PMID: 31868832 PMCID: PMC7774809 DOI: 10.1097/spv.0000000000000808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The purpose of this study was to study the expression of adenosine diphosphate ribosylation factor GTPase-activating protein 3 (ArfGAP3) in the anterior vaginal wall of patients with pelvic organ prolapse (POP).
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29
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Mattera R, Williamson CD, Ren X, Bonifacino JS. The FTS-Hook-FHIP (FHF) complex interacts with AP-4 to mediate perinuclear distribution of AP-4 and its cargo ATG9A. Mol Biol Cell 2020; 31:963-979. [PMID: 32073997 PMCID: PMC7185972 DOI: 10.1091/mbc.e19-11-0658] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 02/05/2020] [Accepted: 02/12/2020] [Indexed: 01/08/2023] Open
Abstract
The heterotetrameric adaptor protein complex 4 (AP-4) is a component of a protein coat associated with the trans-Golgi network (TGN). Mutations in AP-4 subunits cause a complicated form of autosomal-recessive hereditary spastic paraplegia termed AP-4-deficiency syndrome. Recent studies showed that AP-4 mediates export of the transmembrane autophagy protein ATG9A from the TGN to preautophagosomal structures. To identify additional proteins that cooperate with AP-4 in ATG9A trafficking, we performed affinity purification-mass spectrometry followed by validation of the hits by biochemical and functional analyses. This approach resulted in the identification of the fused toes homolog-Hook-FHIP (FHF) complex as a novel AP-4 accessory factor. We found that the AP-4-FHF interaction is mediated by direct binding of the AP-4 μ4 subunit to coiled-coil domains in the Hook1 and Hook2 subunits of FHF. Knockdown of FHF subunits resulted in dispersal of AP-4 and ATG9A from the perinuclear region of the cell, consistent with the previously demonstrated role of the FHF complex in coupling organelles to the microtubule (MT) retrograde motor dynein-dynactin. These findings thus uncover an additional mechanism for the distribution of ATG9A within cells and provide further evidence for a role of protein coats in coupling transport vesicles to MT motors.
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Affiliation(s)
- Rafael Mattera
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892
| | - Chad D. Williamson
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892
| | - Xuefeng Ren
- Department of Molecular and Cell Biology and California Institute of Quantitative Biosciences, University of California, Berkeley, Berkeley, CA 94720
| | - Juan S. Bonifacino
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892
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30
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Beijer D, Sisto A, Van Lent J, Baets J, Timmerman V. Defects in Axonal Transport in Inherited Neuropathies. J Neuromuscul Dis 2020; 6:401-419. [PMID: 31561383 PMCID: PMC6918914 DOI: 10.3233/jnd-190427] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Axonal transport is a highly complex process essential for sustaining proper neuronal functioning. Disturbances can result in an altered neuronal homeostasis, aggregation of cargoes, and ultimately a dying-back degeneration of neurons. The impact of dysfunction in axonal transport is shown by genetic defects in key proteins causing a broad spectrum of neurodegenerative diseases, including inherited peripheral neuropathies. In this review, we provide an overview of the cytoskeletal components, molecular motors and adaptor proteins involved in axonal transport mechanisms and their implication in neuronal functioning. In addition, we discuss the involvement of axonal transport dysfunction in neurodegenerative diseases with a particular focus on inherited peripheral neuropathies. Lastly, we address some recent scientific advances most notably in therapeutic strategies employed in the area of axonal transport, patient-derived iPSC models, in vivo animal models, antisense-oligonucleotide treatments, and novel chemical compounds.
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Affiliation(s)
- Danique Beijer
- Neurogenetics Research Group, Department of Medical Sciences, University of Antwerp, Antwerpen, Belgium.,Neurogenetics Laboratory, Institute Born Bunge, Antwerpen, Belgium
| | - Angela Sisto
- Peripheral Neuropathy Research Group, Department of Biomedical Sciences, University of Antwerp, Antwerpen, Belgium.,Neurogenetics Laboratory, Institute Born Bunge, Antwerpen, Belgium
| | - Jonas Van Lent
- Peripheral Neuropathy Research Group, Department of Biomedical Sciences, University of Antwerp, Antwerpen, Belgium.,Neurogenetics Laboratory, Institute Born Bunge, Antwerpen, Belgium
| | - Jonathan Baets
- Neurogenetics Research Group, Department of Medical Sciences, University of Antwerp, Antwerpen, Belgium.,Neurogenetics Laboratory, Institute Born Bunge, Antwerpen, Belgium.,Neurology Department, University Hospital Antwerp, Antwerpen, Belgium
| | - Vincent Timmerman
- Peripheral Neuropathy Research Group, Department of Biomedical Sciences, University of Antwerp, Antwerpen, Belgium.,Neurogenetics Laboratory, Institute Born Bunge, Antwerpen, Belgium
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31
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Rossor AM, Sleigh JN, Groves M, Muntoni F, Reilly MM, Hoogenraad CC, Schiavo G. Loss of BICD2 in muscle drives motor neuron loss in a developmental form of spinal muscular atrophy. Acta Neuropathol Commun 2020; 8:34. [PMID: 32183910 PMCID: PMC7076953 DOI: 10.1186/s40478-020-00909-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Accepted: 03/01/2020] [Indexed: 12/27/2022] Open
Abstract
Autosomal dominant missense mutations in BICD2 cause Spinal Muscular Atrophy Lower Extremity Predominant 2 (SMALED2), a developmental disease of motor neurons. BICD2 is a key component of the cytoplasmic dynein/dynactin motor complex, which in axons drives the microtubule-dependent retrograde transport of intracellular cargo towards the cell soma. Patients with pathological mutations in BICD2 develop malformations of cortical and cerebellar development similar to Bicd2 knockout (-/-) mice. In this study we sought to re-examine the motor neuron phenotype of conditional Bicd2-/- mice. Bicd2-/- mice show a significant reduction in the number of large calibre motor neurons of the L4 ventral root compared to wild type mice. Muscle-specific knockout of Bicd2 results in a similar reduction in L4 ventral axons comparable to global Bicd2-/- mice. Rab6, a small GTPase required for the sorting of exocytic vesicles from the Trans Golgi Network to the plasma membrane is a major binding partner of BICD2. We therefore examined the secretory pathway in SMALED2 patient fibroblasts and demonstrated that BICD2 is required for physiological flow of constitutive secretory cargoes from the Trans Golgi Network to the plasma membrane using a VSV-G reporter assay. Together, these data indicate that BICD2 loss from muscles is a major driver of non-cell autonomous pathology in the motor nervous system, which has important implications for future therapeutic approaches in SMALED2.
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Affiliation(s)
- Alexander M Rossor
- UCL Queen Square Institute of Neurology, University College London, Queen Square, London, WC1N 3BG, UK.
| | - James N Sleigh
- UCL Queen Square Institute of Neurology, University College London, Queen Square, London, WC1N 3BG, UK
- UK Dementia Research Institute, University College London, London, WC1E 6BT, UK
| | - Michael Groves
- UCL Queen Square Institute of Neurology, University College London, Queen Square, London, WC1N 3BG, UK
| | - Francesco Muntoni
- Dubowitz Neuromuscular Centre and National Institute for Health Research Great Ormond Street Hospital Biomedical Research Centre, University College London Institute of Child Health, London, WC1N 1EH, UK
| | - Mary M Reilly
- UCL Queen Square Institute of Neurology, University College London, Queen Square, London, WC1N 3BG, UK
| | - Casper C Hoogenraad
- Cell Biology, Neurobiology and Biophysics, Department of Biology, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands
| | - Giampietro Schiavo
- UCL Queen Square Institute of Neurology, University College London, Queen Square, London, WC1N 3BG, UK.
- UK Dementia Research Institute, University College London, London, WC1E 6BT, UK.
- Discoveries Centre for Regenerative and Precision Medicine, University College London Campus, London, WC1N 3BG, UK.
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32
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Barbosa J, Martins T, Bange T, Tao L, Conde C, Sunkel C. Polo regulates Spindly to prevent premature stabilization of kinetochore-microtubule attachments. EMBO J 2020; 39:e100789. [PMID: 31849090 PMCID: PMC6960449 DOI: 10.15252/embj.2018100789] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 11/26/2019] [Accepted: 12/02/2019] [Indexed: 12/13/2022] Open
Abstract
Accurate chromosome segregation in mitosis requires sister kinetochores to bind to microtubules from opposite spindle poles. The stability of kinetochore-microtubule attachments is fine-tuned to prevent or correct erroneous attachments while preserving amphitelic interactions. Polo kinase has been implicated in both stabilizing and destabilizing kinetochore-microtubule attachments. However, the mechanism underlying Polo-destabilizing activity remains elusive. Here, resorting to an RNAi screen in Drosophila for suppressors of a constitutively active Polo mutant, we identified a strong genetic interaction between Polo and the Rod-ZW10-Zwilch (RZZ) complex, whose kinetochore accumulation has been shown to antagonize microtubule stability. We find that Polo phosphorylates Spindly and impairs its ability to bind to Zwilch. This precludes dynein-mediated removal of the RZZ from kinetochores and consequently delays the formation of stable end-on attachments. We propose that high Polo-kinase activity following mitotic entry directs the RZZ complex to minimize premature stabilization of erroneous attachments, whereas a decrease in active Polo in later mitotic stages allows the formation of stable amphitelic spindle attachments. Our findings demonstrate that Polo tightly regulates the RZZ-Spindly-dynein module during mitosis to ensure the fidelity of chromosome segregation.
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Affiliation(s)
- João Barbosa
- IBMC—Instituto de Biologia Molecular e CelularUniversidade do PortoPortoPortugal
- i3S, Instituto de Investigação e Inovação em Saúde da Universidade do PortoPortoPortugal
| | | | - Tanja Bange
- MPI für molekulare PhysiologieDortmundGermany
| | - Li Tao
- Department of BiologyUniversity of HawaiiHiloHIUSA
| | - Carlos Conde
- IBMC—Instituto de Biologia Molecular e CelularUniversidade do PortoPortoPortugal
- i3S, Instituto de Investigação e Inovação em Saúde da Universidade do PortoPortoPortugal
| | - Claudio Sunkel
- IBMC—Instituto de Biologia Molecular e CelularUniversidade do PortoPortoPortugal
- i3S, Instituto de Investigação e Inovação em Saúde da Universidade do PortoPortoPortugal
- ICBAS—Instituto de Ciência Biomédica de Abel SalazarUniversidade do PortoPortoPortugal
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34
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Disease-associated mutations hyperactivate KIF1A motility and anterograde axonal transport of synaptic vesicle precursors. Proc Natl Acad Sci U S A 2019; 116:18429-18434. [PMID: 31455732 DOI: 10.1073/pnas.1905690116] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
KIF1A is a kinesin family motor involved in the axonal transport of synaptic vesicle precursors (SVPs) along microtubules (MTs). In humans, more than 10 point mutations in KIF1A are associated with the motor neuron disease hereditary spastic paraplegia (SPG). However, not all of these mutations appear to inhibit the motility of the KIF1A motor, and thus a cogent molecular explanation for how KIF1A mutations lead to neuropathy is not available. In this study, we established in vitro motility assays with purified full-length human KIF1A and found that KIF1A mutations associated with the hereditary SPG lead to hyperactivation of KIF1A motility. Introduction of the corresponding mutations into the Caenorhabditis elegans KIF1A homolog unc-104 revealed abnormal accumulation of SVPs at the tips of axons and increased anterograde axonal transport of SVPs. Our data reveal that hyperactivation of kinesin motor activity, rather than its loss of function, is a cause of motor neuron disease in humans.
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35
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Gao LL, Xu F, Jin Z, Ying XY, Liu JW. Microtubule‑severing protein Katanin p60 ATPase‑containing subunit A‑like 1 is involved in pole‑based spindle organization during mouse oocyte meiosis. Mol Med Rep 2019; 20:3573-3582. [PMID: 31485656 DOI: 10.3892/mmr.2019.10605] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2018] [Accepted: 05/31/2019] [Indexed: 11/05/2022] Open
Abstract
Microtubule‑severing proteins (MTSPs) are a group of microtubule‑associated proteins essential for multiple microtubule‑related processes, including mitosis and meiosis. Katanin p60 ATPase‑containing subunit A‑like 1 (p60 katanin‑like 1) is an MTSP that maintains the density of spindle microtubules at the poles in mitotic cells; however, to date, there have been no studies about its role in female meiosis. Using in vitro‑matured (IVM) oocytes as a model, it was first revealed that p60 katanin‑like 1 was predominant in the ovaries and oocytes, indicating its essential roles in oocyte meiosis. It was also revealed that p60 katanin‑like 1 was concentrated at the spindle poles and co‑localized and interacted with γ‑tubulin, indicating that it may be involved in pole organization. Next, specific siRNA was used to deplete p60 katanin‑like 1; the spindle organization was severely disrupted and characterized by an abnormal width:length ratio, multipolarity and extra aster microtubules out of the main spindles. Finally, it was determined that p60 katanin‑like 1 knockdown retarded oocyte meiosis, reduced fertilization, and caused abnormal mitochondrial distribution. Collectively, these results indicated that p60 katanin‑like 1 is essential for oocyte meiosis by ensuring the integrity of the spindle poles.
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Affiliation(s)
- Lei-Lei Gao
- Department of Gynecology, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, Zhejiang 310014, P.R. China
| | - Fei Xu
- Department of Gynecology, The Affiliated Hospital of Hangzhou Normal University, Hangzhou, Zhejiang 310015, P.R. China
| | - Zhen Jin
- Reproductive Genetic Center, Suzhou Municipal Hospital, Suzhou Hospital of Nanjing, Nanjing, Jiangsu 215000, P.R. China
| | - Xiao-Yan Ying
- Department of Gynecology, The Second Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu 210011, P.R. China
| | - Jin-Wei Liu
- Department of Gynecology, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, Zhejiang 310014, P.R. China
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36
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Marzo MG, Griswold JM, Ruff KM, Buchmeier RE, Fees CP, Markus SM. Molecular basis for dyneinopathies reveals insight into dynein regulation and dysfunction. eLife 2019; 8:47246. [PMID: 31364990 PMCID: PMC6733598 DOI: 10.7554/elife.47246] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 07/30/2019] [Indexed: 12/22/2022] Open
Abstract
Cytoplasmic dynein plays critical roles within the developing and mature nervous systems, including effecting nuclear migration, and retrograde transport of various cargos. Unsurprisingly, mutations in dynein are causative of various developmental neuropathies and motor neuron diseases. These ‘dyneinopathies’ define a broad spectrum of diseases with no known correlation between mutation identity and disease state. To circumvent complications associated with dynein studies in human cells, we employed budding yeast as a screening platform to characterize the motility properties of seventeen disease-correlated dynein mutants. Using this system, we determined the molecular basis for several classes of etiologically related diseases. Moreover, by engineering compensatory mutations, we alleviated the mutant phenotypes in two of these cases, one of which we confirmed with recombinant human dynein. In addition to revealing molecular insight into dynein regulation, our data provide additional evidence that the type of disease may in fact be dictated by the degree of dynein dysfunction. Motor proteins maintain order by transporting biomolecules and various structures within living cells. Dynein is one such motor that moves many types of cargoes along tracks called microtubules, which are spread across the cell’s interior. This motor is particularly important in nerve cells, which can be very long and thus depend heavily on motor proteins to ensure cargoes end up where they are needed. This becomes especially apparent in human diseases that arise as a consequence of mutations in the genes that produce components of the dynein motor. It is assumed that these genetic changes simply prevent dynein from working properly, which ultimately affects the health and survival of cells. However, it is currently unknown what specific effect these mutations have on dynein’s role within the cell, and how these changes lead to particular diseases. Marzo et al. have now used dynein from a budding yeast to closely examine 17 mutations in the dynein gene that are associated with developmental and/or motor neuron diseases in humans. For each mutation, various aspects of how dynein moves (e.g. average speed, distance travelled) were measured and quantitatively compared. The results show that the severity of the effect of each mutation can be directly correlated with the type of disease caused by the mutation. In particular, mutations that lead to less severe defects are found in patients that suffer from various motor neuron diseases, while more severe dynein mutations are found in patients with developmental brain disorders. Marzo et al. confirmed the likely structural changes that caused the defects in dynein’s activity in two of the 17 cases, by engineering additional, restorative mutations that lessened the effects of the primary mutation. These findings reveal links between the molecular impact of defects in the dynein gene and human health. They also confirm that budding yeast is a powerful tool for investigating newly discovered dynein mutations that correlate with disease. This study provides a potential system that could be used to screen drugs that might lessen the effects of specific dynein mutations. However, further work is needed to determine how effective this system will be for drug discovery.
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Affiliation(s)
- Matthew G Marzo
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, United States
| | - Jacqueline M Griswold
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, United States
| | - Kristina M Ruff
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, United States
| | - Rachel E Buchmeier
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, United States
| | - Colby P Fees
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, United States
| | - Steven M Markus
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, United States
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37
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Bergendahl LT, Gerasimavicius L, Miles J, Macdonald L, Wells JN, Welburn JPI, Marsh JA. The role of protein complexes in human genetic disease. Protein Sci 2019; 28:1400-1411. [PMID: 31219644 DOI: 10.1002/pro.3667] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Accepted: 06/10/2019] [Indexed: 12/20/2022]
Abstract
Many human genetic disorders are caused by mutations in protein-coding regions of DNA. Taking protein structure into account has therefore provided key insight into the molecular mechanisms underlying human genetic disease. Although most studies have focused on the intramolecular effects of mutations, the critical role of the assembly of proteins into complexes is being increasingly recognized. Here, we review multiple ways in which consideration of protein complexes can help us to understand and explain the effects of pathogenic mutations. First, we discuss disorders caused by mutations that perturb intersubunit interactions in homomeric and heteromeric complexes. Second, we address how protein complex assembly can facilitate a dominant-negative mechanism, whereby mutated subunits can disrupt the activity of wild-type protein. Third, we show how mutations that change protein expression levels can lead to damaging stoichiometric imbalances. Finally, we review how mutations affecting different subunits of the same heteromeric complex often cause similar diseases, whereas mutations in different interfaces of the same subunit can cause distinct phenotypes.
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Affiliation(s)
- L Therese Bergendahl
- MRC Human Genetics Unit, Institute of Genetics & Molecular Medicine, University of Edinburgh, Edinburgh, EH4 2XU, United Kingdom
| | - Lukas Gerasimavicius
- MRC Human Genetics Unit, Institute of Genetics & Molecular Medicine, University of Edinburgh, Edinburgh, EH4 2XU, United Kingdom
| | - Jamilla Miles
- MRC Human Genetics Unit, Institute of Genetics & Molecular Medicine, University of Edinburgh, Edinburgh, EH4 2XU, United Kingdom
| | - Lewis Macdonald
- MRC Human Genetics Unit, Institute of Genetics & Molecular Medicine, University of Edinburgh, Edinburgh, EH4 2XU, United Kingdom
| | - Jonathan N Wells
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York, 14850
| | - Julie P I Welburn
- Wellcome Trust Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, EH9 3BF, United Kingdom
| | - Joseph A Marsh
- MRC Human Genetics Unit, Institute of Genetics & Molecular Medicine, University of Edinburgh, Edinburgh, EH4 2XU, United Kingdom
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38
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Caracci MO, Fuentealba LM, Marzolo MP. Golgi Complex Dynamics and Its Implication in Prevalent Neurological Disorders. Front Cell Dev Biol 2019; 7:75. [PMID: 31134199 PMCID: PMC6514153 DOI: 10.3389/fcell.2019.00075] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Accepted: 04/18/2019] [Indexed: 12/13/2022] Open
Abstract
Coupling of protein synthesis with protein delivery to distinct subcellular domains is essential for maintaining cellular homeostasis, and defects thereof have consistently been shown to be associated with several diseases. This function is particularly challenging for neurons given their polarized nature and differential protein requirements in synaptic boutons, dendrites, axons, and soma. Long-range trafficking is greatly enhanced in neurons by discrete mini-organelles resembling the Golgi complex (GC) referred to as Golgi outposts (GOPs) which play an essential role in the development of dendritic arborization. In this context, the morphology of the GC is highly plastic, and the polarized distribution of this organelle is necessary for neuronal migration and polarized growth. Furthermore, synaptic components are readily trafficked and modified at GOP suggesting a function for this organelle in synaptic plasticity. However, little is known about GOPs properties and biogenesis and the role of GOP dysregulation in pathology. In this review, we discuss current literature supporting a role for GC dynamics in prevalent neurological disorders such as Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, and epilepsy, and examine the association of these disorders with the wide-ranging effects of GC function on common cellular pathways regulating neuronal excitability, polarity, migration, and organellar stress. First, we discuss the role of Golgins and Golgi-associated proteins in the regulation of GC morphology and dynamics. Then, we consider abnormal GC arrangements observed in neurological disorders and associations with common neuronal defects therein. Finally, we consider the cell signaling pathways involved in the modulation of GC dynamics and argue for a master regulatory role for Reelin signaling, a well-known regulator of neuronal polarity and migration. Determining the cellular pathways involved in shaping the Golgi network will have a direct and profound impact on our current understanding of neurodevelopment and neuropathology and aid the development of novel therapeutic strategies for improved patient care and prognosis.
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Affiliation(s)
- Mario O Caracci
- Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Luz M Fuentealba
- Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - María-Paz Marzolo
- Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
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39
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Abstract
Cytoplasmic dynein-1 (hereafter dynein) is an essential cellular motor that drives the movement of diverse cargos along the microtubule cytoskeleton, including organelles, vesicles and RNAs. A long-standing question is how a single form of dynein can be adapted to a wide range of cellular functions in both interphase and mitosis. Recent progress has provided new insights - dynein interacts with a group of activating adaptors that provide cargo-specific and/or function-specific regulation of the motor complex. Activating adaptors such as BICD2 and Hook1 enhance the stability of the complex that dynein forms with its required activator dynactin, leading to highly processive motility toward the microtubule minus end. Furthermore, activating adaptors mediate specific interactions of the motor complex with cargos such as Rab6-positive vesicles or ribonucleoprotein particles for BICD2, and signaling endosomes for Hook1. In this Cell Science at a Glance article and accompanying poster, we highlight the conserved structural features found in dynein activators, the effects of these activators on biophysical parameters, such as motor velocity and stall force, and the specific intracellular functions they mediate.
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Affiliation(s)
- Mara A Olenick
- University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Erika L F Holzbaur
- University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
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40
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Wang Y, Huynh W, Skokan TD, Lu W, Weiss A, Vale RD. CRACR2a is a calcium-activated dynein adaptor protein that regulates endocytic traffic. J Cell Biol 2019; 218:1619-1633. [PMID: 30814157 PMCID: PMC6504896 DOI: 10.1083/jcb.201806097] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 12/14/2018] [Accepted: 02/07/2019] [Indexed: 01/12/2023] Open
Abstract
Transport of intracellular cargo generally requires coiled-coil adaptor proteins that connect cargo-bound receptors, usually GTPases, to dynein motor complexes. Wang et al. report that two Rab GTPases, CRACR2a and Rab45, contain coiled-coil domains and can directly act as dynein adaptors with CRACR2a–dynein participating in calcium-regulated endocytic trafficking. Cytoplasmic dynein is a minus end–directed microtubule motor that transports intracellular cargoes. Transport is initiated by coiled-coil adaptors that (a) join dynein and its cofactor dynactin into a motile complex and (b) interact with a cargo-bound receptor, which is frequently a Rab GTPase on an organelle. Here, we report two novel dynein adaptors, CRACR2a and Rab45, that have a coiled-coil adaptor domain, a pair of EF-hands, and a Rab GTPase fused into a single polypeptide. CRACR2a-mediated, but not Rab45-mediated, dynein motility is activated by calcium in vitro. In Jurkat T cells, elevation of intracellular calcium activates CRACR2a-mediated dynein transport. We further found that T cell receptor activation induces the formation of CRACR2a puncta at the plasma membrane, which initially associate with the actin cortex and subsequently detach and travel along microtubules, suggestive of an endocytic process. These results provide the first examples of Rab GTPases that directly act as dynein adaptors and implicate CRACR2a–dynein in calcium-regulated endocytic trafficking.
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Affiliation(s)
- Yuxiao Wang
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA.,Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, CA
| | - Walter Huynh
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA.,Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, CA
| | - Taylor D Skokan
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA.,Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, CA
| | - Wen Lu
- Division of Rheumatology, Rosalind Russell and Ephraim P. Engleman Arthritis Research Center, Department of Medicine, University of California, San Francisco, San Francisco, CA
| | - Arthur Weiss
- Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, CA.,Division of Rheumatology, Rosalind Russell and Ephraim P. Engleman Arthritis Research Center, Department of Medicine, University of California, San Francisco, San Francisco, CA
| | - Ronald D Vale
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA .,Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, CA
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41
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Martinez Carrera LA, Gabriel E, Donohoe CD, Hölker I, Mariappan A, Storbeck M, Uhlirova M, Gopalakrishnan J, Wirth B. Novel insights into SMALED2: BICD2 mutations increase microtubule stability and cause defects in axonal and NMJ development. Hum Mol Genet 2019. [PMID: 29528393 DOI: 10.1093/hmg/ddy086] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Bicaudal D2 (BICD2) encodes a highly conserved motor adaptor protein that regulates the dynein-dynactin complex in different cellular processes. Heterozygous mutations in BICD2 cause autosomal dominant lower extremity-predominant spinal muscular atrophy-2 (SMALED2). Although, various BICD2 mutations have been shown to alter interactions with different binding partners or the integrity of the Golgi apparatus, the specific pathological effects of BICD2 mutations underlying SMALED2 remain elusive. Here, we show that the fibroblasts derived from individuals with SMALED2 exhibit stable microtubules. Importantly, this effect was observed regardless of where the BICD2 mutation is located, which unifies the most likely cellular mechanism affecting microtubules. Significantly, overexpression of SMALED2-causing BICD2 mutations in the disease-relevant cell type, motor neurons, also results in an increased microtubule stability which is accompanied by axonal aberrations such as collateral branching and overgrowth. To study the pathological consequences of BICD2 mutations in vivo, and to address the controversial debate whether two of these mutations are neuron or muscle specific, we generated the first Drosophila model of SMALED2. Strikingly, neuron-specific expression of BICD2 mutants resulted in reduced neuromuscular junction size in larvae and impaired locomotion of adult flies. In contrast, expressing BICD2 mutations in muscles had no obvious effect on motor function, supporting a primarily neurological etiology of the disease. Thus, our findings contribute to the better understanding of SMALED2 pathology by providing evidence for a common pathomechanism of BICD2 mutations that increase microtubule stability in motor neurons leading to increased axonal branching and to impaired neuromuscular junction development.
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Affiliation(s)
- Lilian A Martinez Carrera
- Institute of Human Genetics, University of Cologne, 50931 Cologne, Germany.,Institute for Genetics, University of Cologne, 50674 Cologne, Germany.,Center for Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany
| | - Elke Gabriel
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany
| | - Colin D Donohoe
- Institute for Genetics, University of Cologne, 50674 Cologne, Germany.,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, 50931 Cologne, Germany
| | - Irmgard Hölker
- Institute of Human Genetics, University of Cologne, 50931 Cologne, Germany.,Institute for Genetics, University of Cologne, 50674 Cologne, Germany.,Center for Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany
| | - Aruljothi Mariappan
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany
| | - Markus Storbeck
- Institute of Human Genetics, University of Cologne, 50931 Cologne, Germany.,Institute for Genetics, University of Cologne, 50674 Cologne, Germany.,Center for Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany
| | - Mirka Uhlirova
- Institute for Genetics, University of Cologne, 50674 Cologne, Germany.,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, 50931 Cologne, Germany
| | - Jay Gopalakrishnan
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany
| | - Brunhilde Wirth
- Institute of Human Genetics, University of Cologne, 50931 Cologne, Germany.,Institute for Genetics, University of Cologne, 50674 Cologne, Germany.,Center for Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany.,Center for Rare Diseases Cologne, University Hospital of Cologne, 50931 Cologne, Germany
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42
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Olenick MA, Dominguez R, Holzbaur ELF. Dynein activator Hook1 is required for trafficking of BDNF-signaling endosomes in neurons. J Cell Biol 2019; 218:220-233. [PMID: 30373907 PMCID: PMC6314548 DOI: 10.1083/jcb.201805016] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 09/18/2018] [Accepted: 10/15/2018] [Indexed: 01/16/2023] Open
Abstract
Axonal transport is required for neuronal development and survival. Transport from the axon to the soma is driven by the molecular motor cytoplasmic dynein, yet it remains unclear how dynein is spatially and temporally regulated. We find that the dynein effector Hook1 mediates transport of TrkB-BDNF-signaling endosomes in primary hippocampal neurons. Hook1 comigrates with a subpopulation of Rab5 endosomes positive for TrkB and BDNF, which exhibit processive retrograde motility with faster velocities than the overall Rab5 population. Knockdown of Hook1 significantly reduced the motility of BDNF-signaling endosomes without affecting the motility of other organelles. In microfluidic chambers, Hook1 depletion resulted in a significant decrease in the flux and processivity of BDNF-Qdots along the mid-axon, an effect specific for Hook1 but not Hook3. Hook1 depletion inhibited BDNF trafficking to the soma and blocked downstream BDNF- and TrkB-dependent signaling to the nucleus. Together, these studies support a model in which differential association with cargo-specific effectors efficiently regulates dynein in neurons.
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Affiliation(s)
- Mara A Olenick
- The Pennsylvania Muscle Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
- Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
- Center for Engineering Mechanobiology, University of Pennsylvania, Philadelphia, PA
| | - Roberto Dominguez
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
- The Pennsylvania Muscle Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
- Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Erika L F Holzbaur
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
- The Pennsylvania Muscle Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
- Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
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43
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Tjioe M, Ryoo H, Ishitsuka Y, Ge P, Bookwalter C, Huynh W, McKenney RJ, Trybus KM, Selvin PR. Magnetic Cytoskeleton Affinity Purification of Microtubule Motors Conjugated to Quantum Dots. Bioconjug Chem 2018; 29:2278-2286. [PMID: 29932650 PMCID: PMC6452869 DOI: 10.1021/acs.bioconjchem.8b00264] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We develop magnetic cytoskeleton affinity (MiCA) purification, which allows for rapid isolation of molecular motors conjugated to large multivalent quantum dots, in miniscule quantities, which is especially useful for single-molecule applications. When purifying labeled molecular motors, an excess of fluorophores or labels is usually used. However, large labels tend to sediment during the centrifugation step of microtubule affinity purification, a traditionally powerful technique for motor purification. This is solved with MiCA, and purification time is cut from 2 h to 20 min, a significant time-savings when it needs to be done daily. For kinesin, MiCA works with as little as 0.6 μg protein, with yield of ∼27%, compared to 41% with traditional purification. We show the utility of MiCA purification in a force-gliding assay with kinesin, allowing, for the first time, simultaneous determination of whether the force from each motor in a multiple-motor system drives or hinders microtubule movement. Furthermore, we demonstrate rapid purification of just 30 ng dynein-dynactin-BICD2N-QD (DDB-QD), ordinarily a difficult protein-complex to purify.
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Affiliation(s)
| | | | | | | | | | - Walter Huynh
- Department of Cellular and Molecular Pharmacology , University of California, San Francisco , San Francisco , California 94143 , United States
| | - Richard J McKenney
- Molecular & Cellular Biology , University of California, Davis , La Jolla , California 92093 , United States
| | - Kathleen M Trybus
- Department of Molecular Physiology and Biophysics , University of Vermont , Burlington , Vermont 05405 , United States
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44
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McClintock MA, Dix CI, Johnson CM, McLaughlin SH, Maizels RJ, Hoang HT, Bullock SL. RNA-directed activation of cytoplasmic dynein-1 in reconstituted transport RNPs. eLife 2018; 7:36312. [PMID: 29944118 PMCID: PMC6056234 DOI: 10.7554/elife.36312] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 06/19/2018] [Indexed: 12/19/2022] Open
Abstract
Polarised mRNA transport is a prevalent mechanism for spatial control of protein synthesis. However, the composition of transported ribonucleoprotein particles (RNPs) and the regulation of their movement are poorly understood. We have reconstituted microtubule minus end-directed transport of mRNAs using purified components. A Bicaudal-D (BicD) adaptor protein and the RNA-binding protein Egalitarian (Egl) are sufficient for long-distance mRNA transport by the dynein motor and its accessory complex dynactin, thus defining a minimal transport-competent RNP. Unexpectedly, the RNA is required for robust activation of dynein motility. We show that a cis-acting RNA localisation signal promotes the interaction of Egl with BicD, which licenses the latter protein to recruit dynein and dynactin. Our data support a model for BicD activation based on RNA-induced occupancy of two Egl-binding sites on the BicD dimer. Scaffolding of adaptor protein assemblies by cargoes is an attractive mechanism for regulating intracellular transport. In our cells, tiny molecular motors transport the components necessary for life’s biological processes from one location to another. They do so by loading their cargo, and burning up chemical fuel to carry it along pathways made of filaments. For example, one such motor, called dynein, can move molecules of messenger RNA (mRNA) to specific locations within the cell. There, the mRNA will be used as a template to create proteins, which will operate at exactly the right place. Transporting mRNA in this way is critical in processes such as embryonic development and the formation of memories; yet, this mechanism is still poorly understood. Previous work suggested that the mRNA is simply a passenger of the dynein motor, but McClintock et al. asked if this is really the case. Instead, could mRNA regulate its own sorting by controlling the activity of dynein? Studying mRNA trafficking within the complex molecular environment of a cell is challenging, so mRNA transporting machinery was recreated in the laboratory. Only the proteins necessary to build a working system were included in the experiments. In addition to the filaments, the components included dynein and a complex of proteins known as dynactin, which allows the motor to move together with a protein called BICD2. A protein named Egalitarian was used to link the mRNA to BICD2. By filming fluorescently labelled proteins and mRNAs, McClintock et al. discovered that mRNA strongly promotes the movement of the dynein motor. A structured section in the mRNA acts as a docking area for two copies of Egalitarian. This activates BICD2, which then binds to dynein and dynactin, thereby completing the transport machinery. According to these results, the mRNA directs the assembly of the system that will carry it within the cell. Viruses such as HIV and herpesvirus hijack dynein motors to have their genetic information moved around a cell in order to propagate infection. Understanding precisely how mRNA is transported may help to develop new strategies to fight these viruses.
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Affiliation(s)
- Mark A McClintock
- Division of Cell Biology, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
| | - Carly I Dix
- Division of Cell Biology, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
| | - Christopher M Johnson
- Division of Protein and Nucleic Acid Chemistry, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
| | - Stephen H McLaughlin
- Division of Protein and Nucleic Acid Chemistry, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
| | - Rory J Maizels
- Division of Cell Biology, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
| | - Ha Thi Hoang
- Division of Cell Biology, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
| | - Simon L Bullock
- Division of Cell Biology, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
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45
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Sladewski TE, Billington N, Ali MY, Bookwalter CS, Lu H, Krementsova EB, Schroer TA, Trybus KM. Recruitment of two dyneins to an mRNA-dependent Bicaudal D transport complex. eLife 2018; 7:e36306. [PMID: 29944116 PMCID: PMC6056235 DOI: 10.7554/elife.36306] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 06/23/2018] [Indexed: 12/21/2022] Open
Abstract
We investigated the role of full-length Drosophila Bicaudal D (BicD) binding partners in dynein-dynactin activation for mRNA transport on microtubules. Full-length BicD robustly activated dynein-dynactin motility only when both the mRNA binding protein Egalitarian (Egl) and K10 mRNA cargo were present, and electron microscopy showed that both Egl and mRNA were needed to disrupt a looped, auto-inhibited BicD conformation. BicD can recruit two dimeric dyneins, resulting in faster speeds and longer runs than with one dynein. Moving complexes predominantly contained two Egl molecules and one K10 mRNA. This mRNA-bound configuration makes Egl bivalent, likely enhancing its avidity for BicD and thus its ability to disrupt BicD auto-inhibition. Consistent with this idea, artificially dimerized Egl activates dynein-dynactin-BicD in the absence of mRNA. The ability of mRNA cargo to orchestrate the activation of the mRNP (messenger ribonucleotide protein) complex is an elegant way to ensure that only cargo-bound motors are motile.
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Affiliation(s)
- Thomas E Sladewski
- Department of Molecular Physiology and BiophysicsUniversity of VermontBurlingtonUnited States
| | - Neil Billington
- Laboratory of PhysiologyNational Heart, Lung, and Blood Institute, National Institutes of HealthBethesdaUnited States
| | - M Yusuf Ali
- Department of Molecular Physiology and BiophysicsUniversity of VermontBurlingtonUnited States
| | - Carol S Bookwalter
- Department of Molecular Physiology and BiophysicsUniversity of VermontBurlingtonUnited States
| | - Hailong Lu
- Department of Molecular Physiology and BiophysicsUniversity of VermontBurlingtonUnited States
| | - Elena B Krementsova
- Department of Molecular Physiology and BiophysicsUniversity of VermontBurlingtonUnited States
| | - Trina A Schroer
- Department of BiologyJohns Hopkins UniversityBaltimoreUnited States
| | - Kathleen M Trybus
- Department of Molecular Physiology and BiophysicsUniversity of VermontBurlingtonUnited States
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46
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Trimouille A, Obre É, Banneau G, Durr A, Stevanin G, Clot F, Pennamen P, Perez JT, Bailly-Scappaticci C, Rouanet M, Delleci C, Sole G, Mathis S, Goizet C. An in-frame deletion in BICD2 associated with a non-progressive form of SMALED. Clin Neurol Neurosurg 2018; 166:1-3. [DOI: 10.1016/j.clineuro.2018.01.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Revised: 01/03/2018] [Accepted: 01/11/2018] [Indexed: 10/18/2022]
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47
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An Essential Postdevelopmental Role for Lis1 in Mice. eNeuro 2018; 5:eN-NWR-0350-17. [PMID: 29404402 PMCID: PMC5797476 DOI: 10.1523/eneuro.0350-17.2018] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Revised: 01/13/2018] [Accepted: 01/17/2018] [Indexed: 12/15/2022] Open
Abstract
LIS1 mutations cause lissencephaly (LIS), a severe developmental brain malformation. Much less is known about its role in the mature nervous system. LIS1 regulates the microtubule motor cytoplasmic dynein 1 (dynein), and as LIS1 and dynein are both expressed in the adult nervous system, Lis1 could potentially regulate dynein-dependent processes such as axonal transport. We therefore knocked out Lis1 in adult mice using tamoxifen-induced, Cre-ER-mediated recombination. When an actin promoter was used to drive Cre-ER expression (Act-Cre-ER), heterozygous Lis1 knockout (KO) caused no obvious change in viability or behavior, despite evidence of widespread recombination by a Cre reporter three weeks after tamoxifen exposure. In contrast, homozygous Lis1 KO caused the rapid onset of neurological symptoms in both male and female mice. One tamoxifen-dosing regimen caused prominent recombination in the midbrain/hindbrain, PNS, and cardiac/skeletal muscle within a week; these mice developed severe symptoms in that time frame and were killed. A different tamoxifen regimen resulted in delayed recombination in midbrain/hindbrain, but not in other tissues, and also delayed the onset of symptoms. This indicates that Lis1 loss in the midbrain/hindbrain causes the severe phenotype. In support of this, brainstem regions known to house cardiorespiratory centers showed signs of axonal dysfunction in KO animals. Transport defects, neurofilament (NF) alterations, and varicosities were observed in axons in cultured DRG neurons from KO animals. Because no symptoms were observed when a cardiac specific Cre-ER promoter was used, we propose a vital role for Lis1 in autonomic neurons and implicate defective axonal transport in the KO phenotype.
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