1
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Mukhopadhyay AG, Toropova K, Daly L, Wells JN, Vuolo L, Mladenov M, Seda M, Jenkins D, Stephens DJ, Roberts AJ. Structure and tethering mechanism of dynein-2 intermediate chains in intraflagellar transport. EMBO J 2024; 43:1257-1272. [PMID: 38454149 PMCID: PMC10987677 DOI: 10.1038/s44318-024-00060-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 02/06/2024] [Accepted: 02/09/2024] [Indexed: 03/09/2024] Open
Abstract
Dynein-2 is a large multiprotein complex that powers retrograde intraflagellar transport (IFT) of cargoes within cilia/flagella, but the molecular mechanism underlying this function is still emerging. Distinctively, dynein-2 contains two identical force-generating heavy chains that interact with two different intermediate chains (WDR34 and WDR60). Here, we dissect regulation of dynein-2 function by WDR34 and WDR60 using an integrative approach including cryo-electron microscopy and CRISPR/Cas9-enabled cell biology. A 3.9 Å resolution structure shows how WDR34 and WDR60 use surprisingly different interactions to engage equivalent sites of the two heavy chains. We show that cilia can assemble in the absence of either WDR34 or WDR60 individually, but not both subunits. Dynein-2-dependent distribution of cargoes depends more strongly on WDR60, because the unique N-terminal extension of WDR60 facilitates dynein-2 targeting to cilia. Strikingly, this N-terminal extension can be transplanted onto WDR34 and retain function, suggesting it acts as a flexible tether to the IFT "trains" that assemble at the ciliary base. We discuss how use of unstructured tethers represents an emerging theme in IFT train interactions.
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Affiliation(s)
- Aakash G Mukhopadhyay
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
- Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck, University of London, London, UK
| | - Katerina Toropova
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
- Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck, University of London, London, UK
| | - Lydia Daly
- Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck, University of London, London, UK
- Randall Centre of Cell & Molecular Biophysics, King's College London, London, UK
| | - Jennifer N Wells
- Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck, University of London, London, UK
- MRC London Institute of Medical Sciences (LMS), London, UK
| | - Laura Vuolo
- Cell Biology Laboratories, School of Biochemistry, University of Bristol, Bristol, UK
| | - Miroslav Mladenov
- Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck, University of London, London, UK
- Cellular Signalling and Cytoskeletal Function Laboratory, The Francis Crick Institute, London, UK
| | - Marian Seda
- UCL Great Ormond Street Institute of Child Health, University College London, London, UK
| | - Dagan Jenkins
- UCL Great Ormond Street Institute of Child Health, University College London, London, UK
| | - David J Stephens
- Cell Biology Laboratories, School of Biochemistry, University of Bristol, Bristol, UK
| | - Anthony J Roberts
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK.
- Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck, University of London, London, UK.
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2
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Leggere JC, Hibbard JV, Papoulas O, Lee C, Pearson CG, Marcotte EM, Wallingford JB. Label-free proteomic comparison reveals ciliary and nonciliary phenotypes of IFT-A mutants. Mol Biol Cell 2024; 35:ar39. [PMID: 38170584 PMCID: PMC10916875 DOI: 10.1091/mbc.e23-03-0084] [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: 03/10/2023] [Revised: 12/11/2023] [Accepted: 12/18/2023] [Indexed: 01/05/2024] Open
Abstract
DIFFRAC is a powerful method for systematically comparing proteome content and organization between samples in a high-throughput manner. By subjecting control and experimental protein extracts to native chromatography and quantifying the contents of each fraction using mass spectrometry, it enables the quantitative detection of alterations to protein complexes and abundances. Here, we applied DIFFRAC to investigate the consequences of genetic loss of Ift122, a subunit of the intraflagellar transport-A (IFT-A) protein complex that plays a vital role in the formation and function of cilia and flagella, on the proteome of Tetrahymena thermophila. A single DIFFRAC experiment was sufficient to detect changes in protein behavior that mirrored known effects of IFT-A loss and revealed new biology. We uncovered several novel IFT-A-regulated proteins, which we validated through live imaging in Xenopus multiciliated cells, shedding new light on both the ciliary and non-ciliary functions of IFT-A. Our findings underscore the robustness of DIFFRAC for revealing proteomic changes in response to genetic or biochemical perturbation.
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Affiliation(s)
- Janelle C. Leggere
- Department of Molecular Biosciences, University of Texas at Austin, TX 78712
| | - Jaime V.K. Hibbard
- Department of Molecular Biosciences, University of Texas at Austin, TX 78712
| | - Ophelia Papoulas
- Department of Molecular Biosciences, University of Texas at Austin, TX 78712
| | - Chanjae Lee
- Department of Molecular Biosciences, University of Texas at Austin, TX 78712
| | - Chad G. Pearson
- Anschutz Medical Campus, Department of Cell and Developmental Biology, University of Colorado, Aurora, CO 80045
| | - Edward M. Marcotte
- Department of Molecular Biosciences, University of Texas at Austin, TX 78712
| | - John B. Wallingford
- Department of Molecular Biosciences, University of Texas at Austin, TX 78712
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3
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Kalot R, Sentell Z, Kitzler TM, Torban E. Primary cilia and actin regulatory pathways in renal ciliopathies. FRONTIERS IN NEPHROLOGY 2024; 3:1331847. [PMID: 38292052 PMCID: PMC10824913 DOI: 10.3389/fneph.2023.1331847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 12/20/2023] [Indexed: 02/01/2024]
Abstract
Ciliopathies are a group of rare genetic disorders caused by defects to the structure or function of the primary cilium. They often affect multiple organs, leading to brain malformations, congenital heart defects, and anomalies of the retina or skeletal system. Kidney abnormalities are among the most frequent ciliopathic phenotypes manifesting as smaller, dysplastic, and cystic kidneys that are often accompanied by renal fibrosis. Many renal ciliopathies cause chronic kidney disease and often progress to end-stage renal disease, necessitating replacing therapies. There are more than 35 known ciliopathies; each is a rare hereditary condition, yet collectively they account for a significant proportion of chronic kidney disease worldwide. The primary cilium is a tiny microtubule-based organelle at the apex of almost all vertebrate cells. It serves as a "cellular antenna" surveying environment outside the cell and transducing this information inside the cell to trigger multiple signaling responses crucial for tissue morphogenesis and homeostasis. Hundreds of proteins and unique cellular mechanisms are involved in cilia formation. Recent evidence suggests that actin remodeling and regulation at the base of the primary cilium strongly impacts ciliogenesis. In this review, we provide an overview of the structure and function of the primary cilium, focusing on the role of actin cytoskeleton and its regulators in ciliogenesis. We then describe the key clinical, genetic, and molecular aspects of renal ciliopathies. We highlight what is known about actin regulation in the pathogenesis of these diseases with the aim to consider these recent molecular findings as potential therapeutic targets for renal ciliopathies.
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Affiliation(s)
- Rita Kalot
- Department of Medicine and Department of Physiology, McGill University, Montreal, QC, Canada
- The Research Institute of the McGill University Health Center, Montreal, QC, Canada
| | - Zachary Sentell
- Department of Human Genetics, McGill University, Montreal, QC, Canada
| | - Thomas M. Kitzler
- Department of Human Genetics, McGill University, Montreal, QC, Canada
- McGill University Health Center, Montreal, QC, Canada
| | - Elena Torban
- Department of Medicine and Department of Physiology, McGill University, Montreal, QC, Canada
- The Research Institute of the McGill University Health Center, Montreal, QC, Canada
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4
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Arora S, Rana M, Sachdev A, D’Souza JS. Appearing and disappearing acts of cilia. J Biosci 2023. [DOI: 10.1007/s12038-023-00326-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2023]
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5
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Leggere JC, Hibbard JVK, Papoulas O, Lee C, Pearson CG, Marcotte EM, Wallingford JB. Label-free proteomic comparison reveals ciliary and non-ciliary phenotypes of IFT-A mutants. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.08.531778. [PMID: 36945534 PMCID: PMC10028850 DOI: 10.1101/2023.03.08.531778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2023]
Abstract
DIFFRAC is a powerful method for systematically comparing proteome content and organization between samples in a high-throughput manner. By subjecting control and experimental protein extracts to native chromatography and quantifying the contents of each fraction using mass spectrometry, it enables the quantitative detection of alterations to protein complexes and abundances. Here, we applied DIFFRAC to investigate the consequences of genetic loss of Ift122, a subunit of the intraflagellar transport-A (IFT-A) protein complex that plays a vital role in the formation and function of cilia and flagella, on the proteome of Tetrahymena thermophila . A single DIFFRAC experiment was sufficient to detect changes in protein behavior that mirrored known effects of IFT-A loss and revealed new biology. We uncovered several novel IFT-A-regulated proteins, which we validated through live imaging in Xenopus multiciliated cells, shedding new light on both the ciliary and non-ciliary functions of IFT-A. Our findings underscore the robustness of DIFFRAC for revealing proteomic changes in response to genetic or biochemical perturbation.
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6
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Arora S, Rana M, Sachdev A, D'Souza JS. Appearing and disappearing acts of cilia. J Biosci 2023; 48:8. [PMID: 36924208 PMCID: PMC10005925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2023]
Abstract
The past few decades have seen a rise in research on vertebrate cilia and ciliopathy, with interesting collaborations between basic and clinical scientists. This work includes studies on ciliary architecture, composition, evolution, and organelle generation and its biological role. The human body has cells that harbour any of the following four types of cilia: 9+0 motile, 9+0 immotile, 9+2 motile, and 9+2 immotile. Depending on the type, cilia play an important role in cell/fluid movement, mating, sensory perception, and development. Defects in cilia are associated with a wide range of human diseases afflicting the brain, heart, kidneys, respiratory tract, and reproductive system. These are commonly known as ciliopathies and affect millions of people worldwide. Due to their complex genetic etiology, diagnosis and therapy have remained elusive. Although model organisms like Chlamydomonas reinhardtii have been a useful source for ciliary research, reports of a fascinating and rewarding translation of this research into mammalian systems, especially humans, are seen. The current review peeks into one of the complex features of this organelle, namely its birth, the common denominators across the formation of both 9+0 and 9+2 ciliary types, the molecules involved in ciliogenesis, and the steps that go towards regulating their assembly and disassembly.
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Affiliation(s)
- Shashank Arora
- School of Biological Sciences, UM-DAE Centre for Excellence in Basic Sciences, Kalina Campus, Santacruz (E), Mumbai 400098, India
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7
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Nakazato R, Otani H, Ijaz F, Ikegami K. Time-lapse imaging of primary cilium behavior with physiological expression of fluorescent ciliary proteins. Methods Cell Biol 2023; 175:45-68. [PMID: 36967145 DOI: 10.1016/bs.mcb.2022.10.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Almost all cell types of mammals have a small protrusion named a primary cilium on their surface. Primary cilia are enriched by cilia-specific ion channels and G-protein-coupled receptors. They are known to regulate various cellular functions that contribute to the development and homeostasis of living organisms by receiving extracellular signals and transfusing them to the cell body. All functions are performed when the structure of the primary cilia is maintained properly. Abnormalities in primary cilia or their signaling can lead to a collection of diseases in various organs called ciliopathies. The primary cilium is dynamic, static, or fixed. The length of primary cilia varies as the cell cycle progresses and is also altered by extracellular stimuli. Ligand binding to cilia-specific receptors is also known to alter the length. Thus, there is a need for a method to study the morphological changes of the primary cilium in a time-dependent manner, especially under stimuli or mechanical shocks. Time-lapse imaging of primary cilia is one of the most powerful methods to capture the time-dependent behavior of primary cilia. Overexpression of ciliary proteins fused to fluorescent proteins is commonly used for the time-lapse imaging of primary cilia. However, overexpression has drawbacks in terms of artifacts. In addition, the time-lapse imaging of the tiny primary cilia requires some technical tricks. Here, we present a detailed description of the methods for time-lapse imaging of primary cilium, from the generation of cell lines that stably express fluorescent protein-labeled cilia-localized proteins at the physiological level to image analysis, including quantification through image acquisition.
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8
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Hesketh SJ, Mukhopadhyay AG, Nakamura D, Toropova K, Roberts AJ. IFT-A structure reveals carriages for membrane protein transport into cilia. Cell 2022; 185:4971-4985.e16. [PMID: 36462505 DOI: 10.1016/j.cell.2022.11.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 10/13/2022] [Accepted: 11/09/2022] [Indexed: 12/05/2022]
Abstract
Intraflagellar transport (IFT) trains are massive molecular machines that traffic proteins between cilia and the cell body. Each IFT train is a dynamic polymer of two large complexes (IFT-A and -B) and motor proteins, posing a formidable challenge to mechanistic understanding. Here, we reconstituted the complete human IFT-A complex and obtained its structure using cryo-EM. Combined with AlphaFold prediction and genome-editing studies, our results illuminate how IFT-A polymerizes, interacts with IFT-B, and uses an array of β-propeller and TPR domains to create "carriages" of the IFT train that engage TULP adaptor proteins. We show that IFT-A⋅TULP carriages are essential for cilia localization of diverse membrane proteins, as well as ICK-the key kinase regulating IFT train turnaround. These data establish a structural link between IFT-A's distinct functions, provide a blueprint for IFT-A in the train, and shed light on how IFT evolved from a proto-coatomer ancestor.
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Affiliation(s)
- Sophie J Hesketh
- Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck University of London, London, WC1E 7HX, UK
| | - Aakash G Mukhopadhyay
- Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck University of London, London, WC1E 7HX, UK
| | - Dai Nakamura
- Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck University of London, London, WC1E 7HX, UK
| | - Katerina Toropova
- Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck University of London, London, WC1E 7HX, UK.
| | - Anthony J Roberts
- Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck University of London, London, WC1E 7HX, UK.
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9
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Petriman NA, Loureiro-López M, Taschner M, Zacharia NK, Georgieva MM, Boegholm N, Wang J, Mourão A, Russell RB, Andersen JS, Lorentzen E. Biochemically validated structural model of the 15-subunit intraflagellar transport complex IFT-B. EMBO J 2022; 41:e112440. [PMID: 36354106 PMCID: PMC9753473 DOI: 10.15252/embj.2022112440] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 10/17/2022] [Accepted: 10/20/2022] [Indexed: 11/11/2022] Open
Abstract
Cilia are ubiquitous eukaryotic organelles impotant for cellular motility, signaling, and sensory reception. Cilium formation requires intraflagellar transport of structural and signaling components and involves 22 different proteins organized into intraflagellar transport (IFT) complexes IFT-A and IFT-B that are transported by molecular motors. The IFT-B complex constitutes the backbone of polymeric IFT trains carrying cargo between the cilium and the cell body. Currently, high-resolution structures are only available for smaller IFT-B subcomplexes leaving > 50% structurally uncharacterized. Here, we used Alphafold to structurally model the 15-subunit IFT-B complex. The model was validated using cross-linking/mass-spectrometry data on reconstituted IFT-B complexes, X-ray scattering in solution, diffraction from crystals as well as site-directed mutagenesis and protein-binding assays. The IFT-B structure reveals an elongated and highly flexible complex consistent with cryo-electron tomographic reconstructions of IFT trains. The IFT-B complex organizes into IFT-B1 and IFT-B2 parts with binding sites for ciliary cargo and the inactive IFT dynein motor, respectively. Interestingly, our results are consistent with two different binding sites for IFT81/74 on IFT88/70/52/46 suggesting the possibility of different structural architectures for the IFT-B1 complex. Our data present a structural framework to understand IFT-B complex assembly, function, and ciliopathy variants.
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Affiliation(s)
- Narcis A Petriman
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus C, Denmark
| | - Marta Loureiro-López
- Department for Biochemistry and Molecular Biology, University of Southern Denmark, Odense M, Denmark
| | - Michael Taschner
- Department of Fundamental Microbiology, University of Lausanne, Lausanne, Switzerland
| | - Nevin K Zacharia
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus C, Denmark
| | | | - Niels Boegholm
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus C, Denmark
| | - Jiaolong Wang
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus C, Denmark
| | - André Mourão
- Institute of Structural Biology, Helmholtz Zentrum München, Neuherberg, Germany
| | | | - Jens S Andersen
- Department for Biochemistry and Molecular Biology, University of Southern Denmark, Odense M, Denmark
| | - Esben Lorentzen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus C, Denmark
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10
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Pratelli A, Corbo D, Lupetti P, Mencarelli C. The distal central pair segment is structurally specialised and contributes to IFT turnaround and assembly of the tip capping structures in Chlamydomonas flagella. Biol Cell 2022; 114:349-364. [PMID: 36101924 DOI: 10.1111/boc.202200038] [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: 05/10/2022] [Revised: 08/25/2022] [Accepted: 08/29/2022] [Indexed: 11/30/2022]
Abstract
BACKGROUND INFORMATION Cilia and flagella are dynamic organelles whose assembly and maintenance depend on an activetrafficking process known as the IntraFlagellar Transport (IFT), during which trains of IFT protein particles are moved by specific motors and carry flagellar precursors and turnover products along the axoneme. IFT consists of an anterograde (from base to tip) and a retrograde (from tip to base) phase. During IFT turnaround at the flagellar tip, anterograde trains release their cargoes and remodel to form the retrograde trains. Thus, turnaround is crucial for correct IFT. However, current knowledge of its mechanisms is limited. RESULTS We show here that in Chlamydomonas flagella the distal ∼200 nm central pair (CP) segment is structurally differentiated for the presence of a ladder-like structure (LLS). During IFT turnaround, the IFT172 subunit dissociates from the IFT- B protein complex and binds to the LLS-containing CP segment, while the IFT-B complex participates in the assembly of the CP capping structures. The IFT scaffolding function played by the LLS-containing CP segment relies on anchoring components other than the CP microtubules, since IFT turnaround occurs also in the CP-devoid pf18 mutant flagella. CONCLUSIONS During IFT turnaround in Chlamydomonas flagella, i) the LLS and the CP terminal plates act as anchoring platforms for IFT172 and the IFT-B complex, respectively, and ii) during its remodeling, the IFT-B complex contributes to the assembly of the CP capping structures. SIGNIFICANCE Our results indicate that in full length Chlamydomonas flagella IFT remodeling occurs by a specialized mechanism that involves flagellar tip structures and is distinct from the previously proposed model in which the capability to reverse motility would be intrinsic of IFT train and independent by any other flagellar structure.
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Affiliation(s)
- Ambra Pratelli
- Department of Life Sciences, University of Siena, Siena, Italy
| | - Dalia Corbo
- Department of Life Sciences, University of Siena, Siena, Italy
| | - Pietro Lupetti
- Department of Life Sciences, University of Siena, Siena, Italy
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11
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Lucas J, Geisler M. Sequential loss of dynein sequences precedes complete loss in land plants. PLANT PHYSIOLOGY 2022; 189:1237-1240. [PMID: 35385107 PMCID: PMC9237703 DOI: 10.1093/plphys/kiac151] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 02/24/2022] [Indexed: 06/14/2023]
Abstract
Dynein motor proteins, often considered to be missing in land plants, are found in plants that reproduce with flagellated sperm.
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Affiliation(s)
| | - Matt Geisler
- Plant Biology Program, School of Biological Sciences, Southern Illinois University—Carbondale, Carbondale, Illinois 62901, USA
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12
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De-Castro ARG, Rodrigues DRM, De-Castro MJG, Vieira N, Vieira C, Carvalho AX, Gassmann R, Abreu CMC, Dantas TJ. WDR60-mediated dynein-2 loading into cilia powers retrograde IFT and transition zone crossing. J Cell Biol 2022; 221:212746. [PMID: 34739033 PMCID: PMC8576871 DOI: 10.1083/jcb.202010178] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 09/20/2021] [Accepted: 10/13/2021] [Indexed: 12/30/2022] Open
Abstract
The dynein-2 motor complex drives retrograde intraflagellar transport (IFT), playing a pivotal role in the assembly and functions of cilia. However, the mechanisms that regulate dynein-2 motility remain poorly understood. Here, we identify the Caenorhabditis elegans WDR60 homologue, WDR-60, and dissect the roles of this intermediate chain using genome editing and live imaging of endogenous dynein-2/IFT components. We find that loss of WDR-60 impairs dynein-2 recruitment to cilia and its incorporation onto anterograde IFT trains, reducing retrograde motor availability at the ciliary tip. Consistent with this, we show that fewer dynein-2 motors power WDR-60–deficient retrograde IFT trains, which move at reduced velocities and fail to exit cilia, accumulating on the distal side of the transition zone. Remarkably, disrupting the transition zone’s NPHP module almost fully restores ciliary exit of underpowered retrograde trains in wdr-60 mutants. This work establishes WDR-60 as a major contributor to IFT, and the NPHP module as a roadblock to dynein-2 passage through the transition zone.
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Affiliation(s)
- Ana R G De-Castro
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.,IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
| | - Diogo R M Rodrigues
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.,IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal.,Instituto de Ciências Biomédicas Abel Salazar (ICBAS), Universidade do Porto, Porto, Portugal
| | - Maria J G De-Castro
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.,IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
| | - Neide Vieira
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, Braga, Portugal.,ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Cármen Vieira
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.,IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
| | - Ana X Carvalho
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.,IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
| | - Reto Gassmann
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.,IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
| | - Carla M C Abreu
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.,IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
| | - Tiago J Dantas
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.,IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
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13
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Quidwai T, Wang J, Hall EA, Petriman NA, Leng W, Kiesel P, Wells JN, Murphy LC, Keighren MA, Marsh JA, Lorentzen E, Pigino G, Mill P. A WDR35-dependent coat protein complex transports ciliary membrane cargo vesicles to cilia. eLife 2021; 10:e69786. [PMID: 34734804 PMCID: PMC8754431 DOI: 10.7554/elife.69786] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 11/04/2021] [Indexed: 11/13/2022] Open
Abstract
Intraflagellar transport (IFT) is a highly conserved mechanism for motor-driven transport of cargo within cilia, but how this cargo is selectively transported to cilia is unclear. WDR35/IFT121 is a component of the IFT-A complex best known for its role in ciliary retrograde transport. In the absence of WDR35, small mutant cilia form but fail to enrich in diverse classes of ciliary membrane proteins. In Wdr35 mouse mutants, the non-core IFT-A components are degraded and core components accumulate at the ciliary base. We reveal deep sequence homology of WDR35 and other IFT-A subunits to α and ß' COPI coatomer subunits and demonstrate an accumulation of 'coat-less' vesicles that fail to fuse with Wdr35 mutant cilia. We determine that recombinant non-core IFT-As can bind directly to lipids and provide the first in situ evidence of a novel coat function for WDR35, likely with other IFT-A proteins, in delivering ciliary membrane cargo necessary for cilia elongation.
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Affiliation(s)
- Tooba Quidwai
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of EdinburghEdinburghUnited Kingdom
| | - Jiaolong Wang
- Department of Molecular Biology and Genetics, Aarhus UniversityAarhusDenmark
| | - Emma A Hall
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of EdinburghEdinburghUnited Kingdom
| | - Narcis A Petriman
- Department of Molecular Biology and Genetics, Aarhus UniversityAarhusDenmark
| | - Weihua Leng
- Max Planck Institute of Molecular Cell Biology and GeneticsDresdenGermany
| | - Petra Kiesel
- Max Planck Institute of Molecular Cell Biology and GeneticsDresdenGermany
| | - Jonathan N Wells
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of EdinburghEdinburghUnited Kingdom
| | - Laura C Murphy
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of EdinburghEdinburghUnited Kingdom
| | - Margaret A Keighren
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of EdinburghEdinburghUnited Kingdom
| | - Joseph A Marsh
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of EdinburghEdinburghUnited Kingdom
| | - Esben Lorentzen
- Department of Molecular Biology and Genetics, Aarhus UniversityAarhusDenmark
| | - Gaia Pigino
- Max Planck Institute of Molecular Cell Biology and GeneticsDresdenGermany
- Human TechnopoleMilanItaly
| | - Pleasantine Mill
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of EdinburghEdinburghUnited Kingdom
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14
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Wingfield JL, Mekonnen B, Mengoni I, Liu P, Jordan M, Diener D, Pigino G, Lechtreck K. In vivo imaging shows continued association of several IFT-A, IFT-B and dynein complexes while IFT trains U-turn at the tip. J Cell Sci 2021; 134:271904. [PMID: 34415027 DOI: 10.1242/jcs.259010] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 08/12/2021] [Indexed: 01/05/2023] Open
Abstract
Flagellar assembly depends on intraflagellar transport (IFT), a bidirectional motility of protein carriers, the IFT trains. The trains are periodic assemblies of IFT-A and IFT-B subcomplexes and the motors kinesin-2 and IFT dynein. At the tip, anterograde trains are remodeled for retrograde IFT, a process that in Chlamydomonas involves kinesin-2 release and train fragmentation. However, the degree of train disassembly at the tip remains unknown. Here, we performed two-color imaging of fluorescent protein-tagged IFT components, which indicates that IFT-A and IFT-B proteins from a given anterograde train usually return in the same set of retrograde trains. Similarly, concurrent turnaround was typical for IFT-B proteins and the IFT dynein subunit D1bLIC-GFP but severance was observed as well. Our data support a simple model of IFT turnaround, in which IFT-A, IFT-B and IFT dynein typically remain associated at the tip and segments of the anterograde trains convert directly into retrograde trains. Continuous association of IFT-A, IFT-B and IFT dynein during tip remodeling could balance protein entry and exit, preventing the build-up of IFT material in flagella.
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Affiliation(s)
- Jenna L Wingfield
- Department of Cellular Biology, University of Georgia, Athens, GA 30602, USA
| | - Betlehem Mekonnen
- Department of Cellular Biology, University of Georgia, Athens, GA 30602, USA
| | - Ilaria Mengoni
- Department of Cellular Biology, University of Georgia, Athens, GA 30602, USA
| | - Peiwei Liu
- Department of Cellular Biology, University of Georgia, Athens, GA 30602, USA
| | - Mareike Jordan
- Max Planck Institute of Molecular Cell Biology and Genetics, D-01307 Dresden, Germany
| | - Dennis Diener
- Max Planck Institute of Molecular Cell Biology and Genetics, D-01307 Dresden, Germany
| | - Gaia Pigino
- Max Planck Institute of Molecular Cell Biology and Genetics, D-01307 Dresden, Germany.,Human Technopole, Via Cristina Belgioioso 171, 20157 Milan, Italy
| | - Karl Lechtreck
- Department of Cellular Biology, University of Georgia, Athens, GA 30602, USA
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15
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Primary cilia in hard tissue development and diseases. Front Med 2021; 15:657-678. [PMID: 34515939 DOI: 10.1007/s11684-021-0829-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Accepted: 10/13/2020] [Indexed: 10/20/2022]
Abstract
Bone and teeth are hard tissues. Hard tissue diseases have a serious effect on human survival and quality of life. Primary cilia are protrusions on the surfaces of cells. As antennas, they are distributed on the membrane surfaces of almost all mammalian cell types and participate in the development of organs and the maintenance of homeostasis. Mutations in cilium-related genes result in a variety of developmental and even lethal diseases. Patients with multiple ciliary gene mutations present overt changes in the skeletal system, suggesting that primary cilia are involved in hard tissue development and reconstruction. Furthermore, primary cilia act as sensors of external stimuli and regulate bone homeostasis. Specifically, substances are trafficked through primary cilia by intraflagellar transport, which affects key signaling pathways during hard tissue development. In this review, we summarize the roles of primary cilia in long bone development and remodeling from two perspectives: primary cilia signaling and sensory mechanisms. In addition, the cilium-related diseases of hard tissue and the manifestations of mutant cilia in the skeleton and teeth are described. We believe that all the findings will help with the intervention and treatment of related hard tissue genetic diseases.
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16
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Abstract
Axonemal dyneins power the beating of motile cilia and flagella. These massive multimeric motor complexes are assembled in the cytoplasm, and subsequently trafficked to cilia and incorporated into the axonemal superstructure. Numerous cytoplasmic factors are required for the dynein assembly process, and, in mammals, defects lead to primary ciliary dyskinesia, which results in infertility, bronchial problems and failure to set up the left-right body axis correctly. Liquid-liquid phase separation (LLPS) has been proposed to underlie the formation of numerous membrane-less intracellular assemblies or condensates. In multiciliated cells, cytoplasmic assembly of axonemal dyneins also occurs in condensates that exhibit liquid-like properties, including fusion, fission and rapid exchange of components both within condensates and with bulk cytoplasm. However, a recent extensive meta-analysis suggests that the general methods used to define LLPS systems in vivo may not readily distinguish LLPS from other mechanisms. Here, I consider the time and length scales of axonemal dynein heavy chain synthesis, and the possibility that during translation of dynein heavy chain mRNAs, polysomes are crosslinked via partially assembled proteins. I propose that axonemal dynein factory formation in the cytoplasm may be a direct consequence of the sheer scale and complexity of the assembly process itself.
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Affiliation(s)
- Stephen M. King
- Department of Molecular Biology and Biophysics, University of Connecticut Health Center, 263 Farmington Avenue, Farmington, Connecticut 06030-3305, USA
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17
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Antony D, Brunner HG, Schmidts M. Ciliary Dyneins and Dynein Related Ciliopathies. Cells 2021; 10:cells10081885. [PMID: 34440654 PMCID: PMC8391580 DOI: 10.3390/cells10081885] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 07/19/2021] [Accepted: 07/19/2021] [Indexed: 12/22/2022] Open
Abstract
Although ubiquitously present, the relevance of cilia for vertebrate development and health has long been underrated. However, the aberration or dysfunction of ciliary structures or components results in a large heterogeneous group of disorders in mammals, termed ciliopathies. The majority of human ciliopathy cases are caused by malfunction of the ciliary dynein motor activity, powering retrograde intraflagellar transport (enabled by the cytoplasmic dynein-2 complex) or axonemal movement (axonemal dynein complexes). Despite a partially shared evolutionary developmental path and shared ciliary localization, the cytoplasmic dynein-2 and axonemal dynein functions are markedly different: while cytoplasmic dynein-2 complex dysfunction results in an ultra-rare syndromal skeleto-renal phenotype with a high lethality, axonemal dynein dysfunction is associated with a motile cilia dysfunction disorder, primary ciliary dyskinesia (PCD) or Kartagener syndrome, causing recurrent airway infection, degenerative lung disease, laterality defects, and infertility. In this review, we provide an overview of ciliary dynein complex compositions, their functions, clinical disease hallmarks of ciliary dynein disorders, presumed underlying pathomechanisms, and novel developments in the field.
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Affiliation(s)
- Dinu Antony
- Center for Pediatrics and Adolescent Medicine, University Hospital Freiburg, Freiburg University Faculty of Medicine, Mathildenstrasse 1, 79106 Freiburg, Germany;
- Genome Research Division, Human Genetics Department, Radboud University Medical Center, Geert Grooteplein Zuid 10, 6525 KL Nijmegen, The Netherlands;
- Radboud Institute for Molecular Life Sciences (RIMLS), Geert Grooteplein Zuid 10, 6525 KL Nijmegen, The Netherlands
| | - Han G. Brunner
- Genome Research Division, Human Genetics Department, Radboud University Medical Center, Geert Grooteplein Zuid 10, 6525 KL Nijmegen, The Netherlands;
- Radboud Institute for Molecular Life Sciences (RIMLS), Geert Grooteplein Zuid 10, 6525 KL Nijmegen, The Netherlands
| | - Miriam Schmidts
- Center for Pediatrics and Adolescent Medicine, University Hospital Freiburg, Freiburg University Faculty of Medicine, Mathildenstrasse 1, 79106 Freiburg, Germany;
- Genome Research Division, Human Genetics Department, Radboud University Medical Center, Geert Grooteplein Zuid 10, 6525 KL Nijmegen, The Netherlands;
- Radboud Institute for Molecular Life Sciences (RIMLS), Geert Grooteplein Zuid 10, 6525 KL Nijmegen, The Netherlands
- Correspondence: ; Tel.: +49-761-44391; Fax: +49-761-44710
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18
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Abstract
The intraflagellar transport (IFT) system is a remarkable molecular machine used by cells to assemble and maintain the cilium, a long organelle extending from eukaryotic cells that gives rise to motility, sensing and signaling. IFT plays a critical role in building the cilium by shuttling structural components and signaling receptors between the ciliary base and tip. To provide effective transport, IFT-A and IFT-B adaptor protein complexes assemble into highly repetitive polymers, called IFT trains, that are powered by the motors kinesin-2 and IFT-dynein to move bidirectionally along the microtubules. This dynamic system must be precisely regulated to shuttle different cargo proteins between the ciliary tip and base. In this Cell Science at a Glance article and the accompanying poster, we discuss the current structural and mechanistic understanding of IFT trains and how they function as macromolecular machines to assemble the structure of the cilium.
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Affiliation(s)
- Mareike A Jordan
- Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG), Pfotenhauerstraße 108, 01307 Dresden, Germany
| | - Gaia Pigino
- Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG), Pfotenhauerstraße 108, 01307 Dresden, Germany.,Human Technopole, Via Cristina Belgioioso 171, 20157 Milan, Italy
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19
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Wang W, Jack BM, Wang HH, Kavanaugh MA, Maser RL, Tran PV. Intraflagellar Transport Proteins as Regulators of Primary Cilia Length. Front Cell Dev Biol 2021; 9:661350. [PMID: 34095126 PMCID: PMC8170031 DOI: 10.3389/fcell.2021.661350] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Accepted: 04/06/2021] [Indexed: 12/21/2022] Open
Abstract
Primary cilia are small, antenna-like organelles that detect and transduce chemical and mechanical cues in the extracellular environment, regulating cell behavior and, in turn, tissue development and homeostasis. Primary cilia are assembled via intraflagellar transport (IFT), which traffics protein cargo bidirectionally along a microtubular axoneme. Ranging from 1 to 10 μm long, these organelles typically reach a characteristic length dependent on cell type, likely for optimum fulfillment of their specific roles. The importance of an optimal cilia length is underscored by the findings that perturbation of cilia length can be observed in a number of cilia-related diseases. Thus, elucidating mechanisms of cilia length regulation is important for understanding the pathobiology of ciliary diseases. Since cilia assembly/disassembly regulate cilia length, we review the roles of IFT in processes that affect cilia assembly/disassembly, including ciliary transport of structural and membrane proteins, ectocytosis, and tubulin posttranslational modification. Additionally, since the environment of a cell influences cilia length, we also review the various stimuli encountered by renal epithelia in healthy and diseased states that alter cilia length and IFT.
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Affiliation(s)
- Wei Wang
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, United States
| | - Brittany M Jack
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, United States
| | - Henry H Wang
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, United States
| | - Matthew A Kavanaugh
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, United States
| | - Robin L Maser
- Department of Clinical Laboratory Sciences, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, United States
| | - Pamela V Tran
- Department of Anatomy and Cell Biology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS, United States
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20
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Zhang S, Liu Y, Huang Q, Yuan S, Liu H, Shi L, Yap YT, Li W, Zhen J, Zhang L, Hess RA, Zhang Z. Murine germ cell-specific disruption of Ift172 causes defects in spermiogenesis and male fertility. Reproduction 2021; 159:409-421. [PMID: 31958312 DOI: 10.1530/rep-17-0789] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Accepted: 01/20/2020] [Indexed: 01/21/2023]
Abstract
Intraflagellar transport (IFT) is a conserved mechanism essential for the assembly and maintenance of most eukaryotic cilia and flagella. IFT172 is a component of the IFT complex. Global disruption of mouse Ift172 gene caused typical phenotypes of ciliopathy. Mouse Ift172 gene appears to translate two major proteins; the full-length protein is highly expressed in the tissues enriched in cilia and the smaller 130 kDa one is only abundant in the testis. In male germ cells, IFT172 is highly expressed in the manchette of elongating spermatids. A germ cell-specific Ift172 mutant mice were generated, and the mutant mice did not show gross abnormalities. There was no difference in testis/body weight between the control and mutant mice, but more than half of the adult homozygous mutant males were infertile and associated with abnormally developed germ cells in the spermiogenesis phase. The cauda epididymides in mutant mice contained less developed sperm that showed significantly reduced motility, and these sperm had multiple defects in ultrastructure and bent tails. In the mutant mice, testicular expression levels of some IFT components, including IFT20, IFT27, IFT74, IFT81 and IFT140, and a central apparatus protein SPAG16L were not changed. However, expression levels of ODF2, a component of the outer dense fiber, and AKAP4, a component of fibrous sheath, and two IFT components IFT25 and IFT57 were dramatically reduced. Our findings demonstrate that IFT172 is essential for normal male fertility and spermiogenesis in mice, probably by modulating specific IFT proteins and transporting/assembling unique accessory structural proteins into spermatozoa.
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Affiliation(s)
- Shiyang Zhang
- School of Public Health, Wuhan University of Science and Technology, Wuhan, Hubei, China.,Department of Physiology, Wayne State University, Detroit, Michigan, USA
| | - Yunhao Liu
- School of Public Health, Wuhan University of Science and Technology, Wuhan, Hubei, China.,Hubei Province Key Laboratory of Occupational Hazard Identification and Control, Wuhan University of Science and Technology, Wuhan, Hubei, China
| | - Qian Huang
- School of Public Health, Wuhan University of Science and Technology, Wuhan, Hubei, China.,Department of Physiology, Wayne State University, Detroit, Michigan, USA
| | - Shuo Yuan
- School of Public Health, Wuhan University of Science and Technology, Wuhan, Hubei, China.,Department of Physiology, Wayne State University, Detroit, Michigan, USA
| | - Hong Liu
- School of Public Health, Wuhan University of Science and Technology, Wuhan, Hubei, China.,Department of Physiology, Wayne State University, Detroit, Michigan, USA
| | - Lin Shi
- School of Public Health, Wuhan University of Science and Technology, Wuhan, Hubei, China.,Department of Physiology, Wayne State University, Detroit, Michigan, USA
| | - Yi Tian Yap
- Department of Physiology, Wayne State University, Detroit, Michigan, USA
| | - Wei Li
- Department of Physiology, Wayne State University, Detroit, Michigan, USA
| | - Jingkai Zhen
- School of Public Health, Wuhan University of Science and Technology, Wuhan, Hubei, China
| | - Ling Zhang
- School of Public Health, Wuhan University of Science and Technology, Wuhan, Hubei, China.,Hubei Province Key Laboratory of Occupational Hazard Identification and Control, Wuhan University of Science and Technology, Wuhan, Hubei, China
| | - Rex A Hess
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois, Urbana, Illinois, USA
| | - Zhibing Zhang
- Department of Physiology, Wayne State University, Detroit, Michigan, USA.,Department of Obstetrics and Gynecology, Wayne State University, Detroit, Michigan, USA
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21
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Hibbard JVK, Vazquez N, Satija R, Wallingford JB. Protein turnover dynamics suggest a diffusion-to-capture mechanism for peri-basal body recruitment and retention of intraflagellar transport proteins. Mol Biol Cell 2021; 32:1171-1180. [PMID: 33826363 PMCID: PMC8351562 DOI: 10.1091/mbc.e20-11-0717] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Intraflagellar transport (IFT) is essential for construction and maintenance of cilia. IFT proteins concentrate at the basal body where they are thought to assemble into trains and bind cargoes for transport. To study the mechanisms of IFT recruitment to this peri-basal body pool, we quantified protein dynamics of eight IFT proteins, as well as five other basal body localizing proteins using fluorescence recovery after photobleaching in vertebrate multiciliated cells. We found that members of the IFT-A and IFT-B protein complexes show distinct turnover kinetics from other basal body components. Additionally, known IFT subcomplexes displayed shared dynamics, suggesting shared basal body recruitment and/or retention mechanisms. Finally, we evaluated the mechanisms of basal body recruitment by depolymerizing cytosolic MTs, which suggested that IFT proteins are recruited to basal bodies through a diffusion-to-capture mechanism. Our survey of IFT protein dynamics provides new insights into IFT recruitment to basal bodies, a crucial step in ciliogenesis and ciliary signaling.
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Affiliation(s)
- Jaime V K Hibbard
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712
| | - Neftali Vazquez
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712
| | - Rohit Satija
- California Institute of Quantitative Biosciences, University of California, Berkeley, Berkeley, CA 94720
| | - John B Wallingford
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712
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22
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Huang S, Dougherty LL, Avasthi P. Separable roles for RanGTP in nuclear and ciliary trafficking of a kinesin-2 subunit. J Biol Chem 2021; 296:100117. [PMID: 33234597 PMCID: PMC7948393 DOI: 10.1074/jbc.ra119.010936] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 11/16/2020] [Accepted: 11/24/2020] [Indexed: 01/05/2023] Open
Abstract
Kinesin is part of the microtubule-binding motor protein superfamily, which serves important roles in cell division and intraorganellar transport. The heterotrimeric kinesin-2, consisting of the heterodimeric motor subunits, kinesin family member 3A/3B (KIF3A/3B), and kinesin-associated protein 3 (KAP3), is highly conserved across species from the unicellular eukaryote Chlamydomonas to humans. It plays diverse roles in cargo transport including anterograde (base to tip) trafficking in cilia. However, the molecular determinants mediating trafficking of heterotrimeric kinesin-2 itself are poorly understood. It has been previously suggested that ciliary transport is analogous to nuclear transport mechanisms. Using Chlamydomonas and human telomerase reverse transcriptase-retinal pigment epithelial cell line, we show that RanGTP, a small GTPase that dictates nuclear transport, regulates ciliary trafficking of KAP3, a key component for functional kinesin-2. We found that the armadillo-repeat region 6 to 9 (ARM6-9) of KAP3, required for its nuclear translocation, is also necessary and sufficient for its targeting to the ciliary base. Given that KAP3 is essential for cilium formation and there are the emerging roles for RanGTP/importin β in ciliary protein targeting, we further investigated the effect of RanGTP in cilium formation and maintenance. We found that precise control of RanGTP levels, revealed by different Ran mutants, is crucial for cilium formation and maintenance. Most importantly, we were able to provide orthogonal support in an algal model system that segregates RanGTP regulation of ciliary protein trafficking from its nuclear roles. Our work provides important support for the model that nuclear import mechanisms have been co-opted for independent roles in ciliary import.
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Affiliation(s)
- Shengping Huang
- Department of Ophthalmology, University of Kansas Medical Center, Kansas City, Kansas, USA.
| | - Larissa L Dougherty
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, Kansas, USA; Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover, New Hampshire, USA
| | - Prachee Avasthi
- Department of Ophthalmology, University of Kansas Medical Center, Kansas City, Kansas, USA; Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, Kansas, USA; Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover, New Hampshire, USA.
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23
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Zhu X, Wang J, Li S, Lechtreck K, Pan J. IFT54 directly interacts with kinesin-II and IFT dynein to regulate anterograde intraflagellar transport. EMBO J 2020; 40:e105781. [PMID: 33368450 DOI: 10.15252/embj.2020105781] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 11/30/2020] [Accepted: 12/04/2020] [Indexed: 12/31/2022] Open
Abstract
The intraflagellar transport (IFT) machinery consists of the anterograde motor kinesin-II, the retrograde motor IFT dynein, and the IFT-A and -B complexes. However, the interaction among IFT motors and IFT complexes during IFT remains elusive. Here, we show that the IFT-B protein IFT54 interacts with both kinesin-II and IFT dynein and regulates anterograde IFT. Deletion of residues 342-356 of Chlamydomonas IFT54 resulted in diminished anterograde traffic of IFT and accumulation of IFT motors and complexes in the proximal region of cilia. IFT54 directly interacted with kinesin-II and this interaction was strengthened for the IFT54Δ342-356 mutant in vitro and in vivo. The deletion of residues 261-275 of IFT54 reduced ciliary entry and anterograde traffic of IFT dynein with accumulation of IFT complexes near the ciliary tip. IFT54 directly interacted with IFT dynein subunit D1bLIC, and deletion of residues 261-275 reduced this interaction. The interactions between IFT54 and the IFT motors were also observed in mammalian cells. Our data indicate a central role for IFT54 in binding the IFT motors during anterograde IFT.
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Affiliation(s)
- Xin Zhu
- MOE Key Laboratory of Protein Sciences, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China.,Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong Province, China
| | - Jieling Wang
- MOE Key Laboratory of Protein Sciences, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Shufen Li
- MOE Key Laboratory of Protein Sciences, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Karl Lechtreck
- Department of Cellular Biology, University of Georgia, Athens, GA, USA
| | - Junmin Pan
- MOE Key Laboratory of Protein Sciences, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China.,Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong Province, China
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24
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Xu N, Oltmanns A, Zhao L, Girot A, Karimi M, Hoepfner L, Kelterborn S, Scholz M, Beißel J, Hegemann P, Bäumchen O, Liu LN, Huang K, Hippler M. Altered N-glycan composition impacts flagella-mediated adhesion in Chlamydomonas reinhardtii. eLife 2020; 9:58805. [PMID: 33300874 PMCID: PMC7759384 DOI: 10.7554/elife.58805] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 12/09/2020] [Indexed: 01/22/2023] Open
Abstract
For the unicellular alga Chlamydomonas reinhardtii, the presence of N-glycosylated proteins on the surface of two flagella is crucial for both cell-cell interaction during mating and flagellar surface adhesion. However, it is not known whether only the presence or also the composition of N-glycans attached to respective proteins is important for these processes. To this end, we tested several C. reinhardtii insertional mutants and a CRISPR/Cas9 knockout mutant of xylosyltransferase 1A, all possessing altered N-glycan compositions. Taking advantage of atomic force microscopy and micropipette force measurements, our data revealed that reduction in N-glycan complexity impedes the adhesion force required for binding the flagella to surfaces. This results in impaired polystyrene bead binding and transport but not gliding of cells on solid surfaces. Notably, assembly, intraflagellar transport, and protein import into flagella are not affected by altered N-glycosylation. Thus, we conclude that proper N-glycosylation of flagellar proteins is crucial for adhering C. reinhardtii cells onto surfaces, indicating that N-glycans mediate surface adhesion via direct surface contact.
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Affiliation(s)
- Nannan Xu
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Anne Oltmanns
- Institute for Plant Biology and Biotechnology, University of Münster, Münster, Germany
| | - Longsheng Zhao
- Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom.,State Key Laboratory of Microbial Technology, and Marine Biotechnology Research Center, Shandong University, Qingdao, China
| | - Antoine Girot
- Max Planck Institute for Dynamics and Self-Organization (MPIDS), Göttingen, Germany
| | - Marzieh Karimi
- Max Planck Institute for Dynamics and Self-Organization (MPIDS), Göttingen, Germany
| | - Lara Hoepfner
- Institute for Plant Biology and Biotechnology, University of Münster, Münster, Germany
| | - Simon Kelterborn
- Institute of Biology, Experimental Biophysics, Humboldt University of Berlin, Berlin, Germany
| | - Martin Scholz
- Institute for Plant Biology and Biotechnology, University of Münster, Münster, Germany
| | - Julia Beißel
- Institute for Plant Biology and Biotechnology, University of Münster, Münster, Germany
| | - Peter Hegemann
- Institute of Biology, Experimental Biophysics, Humboldt University of Berlin, Berlin, Germany
| | - Oliver Bäumchen
- Max Planck Institute for Dynamics and Self-Organization (MPIDS), Göttingen, Germany.,Experimental Physics V, University of Bayreuth, Bayreuth, Germany
| | - Lu-Ning Liu
- Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom.,College of Marine Life Sciences, and Frontiers Science Center for Deep Ocean Multispheres and Earth System, Ocean University of China, Qingdao, China
| | - Kaiyao Huang
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Michael Hippler
- Institute for Plant Biology and Biotechnology, University of Münster, Münster, Germany.,Institute of Plant Science and Resources, Okayama University, Kurashiki, Japan
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25
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Webb S, Mukhopadhyay AG, Roberts AJ. Intraflagellar transport trains and motors: Insights from structure. Semin Cell Dev Biol 2020; 107:82-90. [PMID: 32684327 PMCID: PMC7561706 DOI: 10.1016/j.semcdb.2020.05.021] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 05/19/2020] [Accepted: 05/26/2020] [Indexed: 11/17/2022]
Abstract
Intraflagellar transport (IFT) sculpts the proteome of cilia and flagella; the antenna-like organelles found on the surface of virtually all human cell types. By delivering proteins to the growing ciliary tip, recycling turnover products, and selectively transporting signalling molecules, IFT has critical roles in cilia biogenesis, quality control, and signal transduction. IFT involves long polymeric arrays, termed IFT trains, which move to and from the ciliary tip under the power of the microtubule-based motor proteins kinesin-II and dynein-2. Recent top-down and bottom-up structural biology approaches are converging on the molecular architecture of the IFT train machinery. Here we review these studies, with a focus on how kinesin-II and dynein-2 assemble, attach to IFT trains, and undergo precise regulation to mediate bidirectional transport.
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Affiliation(s)
- Stephanie Webb
- Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck, University of London, Malet Street, London, United Kingdom
| | - Aakash G Mukhopadhyay
- Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck, University of London, Malet Street, London, United Kingdom
| | - Anthony J Roberts
- Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck, University of London, Malet Street, London, United Kingdom.
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26
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Shi L, Zhou T, Huang Q, Zhang S, Li W, Zhang L, Hess RA, Pazour GJ, Zhang Z. Intraflagellar transport protein 74 is essential for spermatogenesis and male fertility in mice†. Biol Reprod 2020; 101:188-199. [PMID: 31004481 DOI: 10.1093/biolre/ioz071] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2018] [Revised: 03/22/2019] [Accepted: 04/18/2019] [Indexed: 12/30/2022] Open
Abstract
Intraflagellar transport protein 74 (IFT74) is a component of the core intraflagellar transport complex, a bidirectional movement of large particles along the axoneme microtubules for cilia formation. In this study, we investigated its role in sperm flagella formation and discovered that mice deficiency in Ift74 gene in male germ cells were infertile with low sperm count and immotile sperm. The few developed spermatozoa displayed misshaped heads and short tails. Transmission electron microscopy revealed abnormal flagellar axonemes in the seminiferous tubules where sperm are made. Clusters of unassembled microtubules were present in the spermatids. Testicular expression levels of IFT27, IFT57, IFT81, IFT88, and IFT140 proteins were significantly reduced in the conditional Ift74 mutant mice, with the exception of IFT20 and IFT25. The levels of outer dense fiber 2 and sperm-associated antigen 16L proteins were also not changed. However, the processed A-Kinase anchor protein, a major component of the fibrous sheath, a unique structure of sperm tail, was significantly reduced. Our study demonstrates that IFT74 is essential for mouse sperm formation, probably through assembly of the core axoneme and fibrous sheath, and suggests that IFT74 may be a potential genetic factor affecting male reproduction in man.
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Affiliation(s)
- Lin Shi
- School of Public Health, Wuhan University of Science and Technology, Wuhan, Hubei, China.,Department of Physiology, Wayne State University, Detroit, Michigan, USA
| | - Ting Zhou
- School of Public Health, Wuhan University of Science and Technology, Wuhan, Hubei, China.,Department of Physiology, Wayne State University, Detroit, Michigan, USA
| | - Qian Huang
- School of Public Health, Wuhan University of Science and Technology, Wuhan, Hubei, China.,Department of Physiology, Wayne State University, Detroit, Michigan, USA
| | - Shiyang Zhang
- School of Public Health, Wuhan University of Science and Technology, Wuhan, Hubei, China.,Department of Physiology, Wayne State University, Detroit, Michigan, USA
| | - Wei Li
- Department of Physiology, Wayne State University, Detroit, Michigan, USA
| | - Ling Zhang
- School of Public Health, Wuhan University of Science and Technology, Wuhan, Hubei, China
| | - Rex A Hess
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois, Urbana, Illinois, USA
| | - Gregory J Pazour
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Zhibing Zhang
- Department of Physiology, Wayne State University, Detroit, Michigan, USA.,Department of Obstetrics/Gynecology, Wayne State University, Detroit, Michigan, USA
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27
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Upadhyai P, Guleria VS, Udupa P. Characterization of primary cilia features reveal cell-type specific variability in in vitro models of osteogenic and chondrogenic differentiation. PeerJ 2020; 8:e9799. [PMID: 32884864 PMCID: PMC7444507 DOI: 10.7717/peerj.9799] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Accepted: 08/03/2020] [Indexed: 12/12/2022] Open
Abstract
Primary cilia are non-motile sensory antennae present on most vertebrate cell surfaces. They serve to transduce and integrate diverse external stimuli into functional cellular responses vital for development, differentiation and homeostasis. Ciliary characteristics, such as length, structure and frequency are often tailored to distinct differentiated cell states. Primary cilia are present on a variety of skeletal cell-types and facilitate the assimilation of sensory cues to direct skeletal development and repair. However, there is limited knowledge of ciliary variation in response to the activation of distinct differentiation cascades in different skeletal cell-types. C3H10T1/2, MC3T3-E1 and ATDC5 cells are mesenchymal stem cells, preosteoblast and prechondrocyte cell-lines, respectively. They are commonly employed in numerous in vitro studies, investigating the molecular mechanisms underlying osteoblast and chondrocyte differentiation, skeletal disease and repair. Here we sought to evaluate the primary cilia length and frequencies during osteogenic differentiation in C3H10T1/2 and MC3T3-E1 and chondrogenic differentiation in ATDC5 cells, over a period of 21 days. Our data inform on the presence of stable cilia to orchestrate signaling and dynamic alterations in their features during extended periods of differentiation. Taken together with existing literature these findings reflect the occurrence of not only lineage but cell-type specific variation in ciliary attributes during differentiation. These results extend our current knowledge, shining light on the variabilities in primary cilia features correlated with distinct differentiated cell phenotypes. It may have broader implications in studies using these cell-lines to explore cilia dependent cellular processes and treatment modalities for skeletal disorders centered on cilia modulation.
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Affiliation(s)
- Priyanka Upadhyai
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Vishal Singh Guleria
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Prajna Udupa
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, Karnataka, India
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28
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Liu G, Wang L, Pan J. Chlamydomonas WDR92 in association with R2TP-like complex and multiple DNAAFs to regulate ciliary dynein preassembly. J Mol Cell Biol 2020; 11:770-780. [PMID: 30428028 PMCID: PMC6821370 DOI: 10.1093/jmcb/mjy067] [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] [Received: 09/20/2018] [Revised: 10/30/2018] [Accepted: 11/13/2018] [Indexed: 11/17/2022] Open
Abstract
The motility of cilia or eukaryotic flagella is powered by the axonemal dyneins, which are preassembled in the cytoplasm by proteins termed dynein arm assembly factors (DNAAFs) before being transported to and assembled on the ciliary axoneme. Here, we characterize the function of WDR92 in Chlamydomonas. Loss of WDR92, a cytoplasmic protein, in a mutant wdr92 generated by DNA insertional mutagenesis resulted in aflagellate cells or cells with stumpy or short flagella, disappearance of axonemal dynein arms, and diminishment of dynein arm heavy chains in the cytoplasm, suggesting that WDR92 is a DNAAF. Immunoprecipitation of WDR92 followed by mass spectrometry identified inner dynein arm heavy chains and multiple DNAAFs including RuvBL1, RPAP3, MOT48, ODA7, and DYX1C. The PIH1 domain-containing protein MOT48 formed a R2TP-like complex with RuvBL1/2 and RPAP3, while PF13, another PIH1 domain-containing protein with function in dynein preassembly, did not. Interestingly, the third PIH1 domain-containing protein TWI1 was not related to flagellar motility. WDR92 physically interacted with the R2TP-like complex and the other identified DNNAFs. Our data suggest that WDR92 functions in association with the HSP90 co-chaperone R2TP-like complex as well as linking other DNAAFs in dynein preassembly.
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Affiliation(s)
- Guang Liu
- MOE Key Laboratory of Protein Sciences, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Limei Wang
- MOE Key Laboratory of Protein Sciences, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Junmin Pan
- MOE Key Laboratory of Protein Sciences, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China.,Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
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29
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Nakayama K, Katoh Y. Architecture of the IFT ciliary trafficking machinery and interplay between its components. Crit Rev Biochem Mol Biol 2020; 55:179-196. [PMID: 32456460 DOI: 10.1080/10409238.2020.1768206] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Cilia and flagella serve as cellular antennae and propellers in various eukaryotic cells, and contain specific receptors and ion channels as well as components of axonemal microtubules and molecular motors to achieve their sensory and motile functions. Not only the bidirectional trafficking of specific proteins within cilia but also their selective entry and exit across the ciliary gate is mediated by the intraflagellar transport (IFT) machinery with the aid of motor proteins. The IFT-B complex, which is powered by the kinesin-2 motor, mediates anterograde protein trafficking from the base to the tip of cilia, whereas the IFT-A complex together with the dynein-2 complex mediates retrograde protein trafficking. The BBSome complex connects ciliary membrane proteins to the IFT machinery. Defects in any component of this trafficking machinery lead to abnormal ciliogenesis and ciliary functions, and results in a broad spectrum of disorders, collectively called the ciliopathies. In this review article, we provide an overview of the architectures of the components of the IFT machinery and their functional interplay in ciliary protein trafficking.
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Affiliation(s)
- Kazuhisa Nakayama
- Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, Japan
| | - Yohei Katoh
- Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, Japan
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30
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Ma R, Hendel NL, Marshall WF, Qin H. Speed and Diffusion of Kinesin-2 Are Competing Limiting Factors in Flagellar Length-Control Model. Biophys J 2020; 118:2790-2800. [PMID: 32365327 DOI: 10.1016/j.bpj.2020.03.034] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 03/18/2020] [Accepted: 03/24/2020] [Indexed: 10/24/2022] Open
Abstract
Flagellar length control in Chlamydomonas is a tractable model system for studying the general question of organelle size regulation. We have previously proposed that the diffusive return of the kinesin motor that powers intraflagellar transport can play a key role in length regulation. Here, we explore how the motor speed and diffusion coefficient for the return of kinesin-2 affect flagellar growth kinetics. We find that the system can exist in two distinct regimes, one dominated by motor speed and one by diffusion coefficient. Depending on length, a flagellum can switch between these regimes. Our results indicate that mutations can affect the length in distinct ways. We discuss our theory's implication for flagellar growth influenced by beating and provide possible explanations for the experimental observation that a beating flagellum is usually longer than its immotile mutant. These results demonstrate how our simple model can suggest explanations for mutant phenotypes.
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Affiliation(s)
- Rui Ma
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut
| | - Nathan L Hendel
- Department of Biochemistry and Biophysics, University of California, San Francisco, California; Bioinformatics Graduate Group, University of California, San Francisco, California
| | - Wallace F Marshall
- Department of Biochemistry and Biophysics, University of California, San Francisco, California
| | - Hongmin Qin
- Department of Biology, Texas A&M University, College Station, Texas.
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31
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Vuolo L, Stevenson NL, Mukhopadhyay AG, Roberts AJ, Stephens DJ. Cytoplasmic dynein-2 at a glance. J Cell Sci 2020; 133:133/6/jcs240614. [DOI: 10.1242/jcs.240614] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
ABSTRACT
Cytoplasmic dynein-2 is a motor protein complex that drives the movement of cargoes along microtubules within cilia, facilitating the assembly of these organelles on the surface of nearly all mammalian cells. Dynein-2 is crucial for ciliary function, as evidenced by deleterious mutations in patients with skeletal abnormalities. Long-standing questions include how the dynein-2 complex is assembled, regulated, and switched between active and inactive states. A combination of model organisms, in vitro cell biology, live-cell imaging, structural biology and biochemistry has advanced our understanding of the dynein-2 motor. In this Cell Science at a Glance article and the accompanying poster, we discuss the current understanding of dynein-2 and its roles in ciliary assembly and function.
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Affiliation(s)
- Laura Vuolo
- Cell Biology Laboratories, School of Biochemistry, Faculty of Life Sciences, University of Bristol, Bristol BS8 1TD, UK
| | - Nicola L. Stevenson
- Cell Biology Laboratories, School of Biochemistry, Faculty of Life Sciences, University of Bristol, Bristol BS8 1TD, UK
| | - Aakash G. Mukhopadhyay
- Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck, University of London, London WC1E 7HX, UK
| | - Anthony J. Roberts
- Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck, University of London, London WC1E 7HX, UK
| | - David J. Stephens
- Cell Biology Laboratories, School of Biochemistry, Faculty of Life Sciences, University of Bristol, Bristol BS8 1TD, UK
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32
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Sonar P, Youyen W, Cleetus A, Wisanpitayakorn P, Mousavi SI, Stepp WL, Hancock WO, Tüzel E, Ökten Z. Kinesin-2 from C. reinhardtii Is an Atypically Fast and Auto-inhibited Motor that Is Activated by Heterotrimerization for Intraflagellar Transport. Curr Biol 2020; 30:1160-1166.e5. [PMID: 32142698 DOI: 10.1016/j.cub.2020.01.046] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 12/04/2019] [Accepted: 01/14/2020] [Indexed: 11/17/2022]
Abstract
Construction and function of virtually all cilia require the universally conserved process of intraflagellar transport (IFT) [1, 2]. During the atypically fast IFT in the green alga C. reinhardtii, on average, 10 kinesin-2 motors "line up" in a tight assembly on the trains [3], provoking the question of how these motors coordinate their action to ensure smooth and fast transport along the flagellum without standing in each other's way. Here, we show that the heterodimeric FLA8/10 kinesin-2 alone is responsible for the atypically fast IFT in C. reinhardtii. Notably, in single-molecule studies, FLA8/10 moved at speeds matching those of in vivo IFT [4] but additionally displayed a slow velocity distribution, indicative of auto-inhibition. Addition of the KAP subunit to generate the heterotrimeric FLA8/10/KAP relieved this inhibition, thus providing a mechanistic rationale for heterotrimerization with the KAP subunit fully activating FLA8/10 for IFT in vivo. Finally, we linked fast FLA8/10 and slow KLP11/20 kinesin-2 from C. reinhardtii and C. elegans through a DNA tether to understand the molecular underpinnings of motor coordination during IFT in vivo. For motor pairs from both species, the co-transport velocities very nearly matched the single-molecule velocities, and both complexes spent roughly 80% of the time with only one of the two motors attached to the microtubule. Thus, irrespective of phylogeny and kinetic properties, kinesin-2 motors work mostly alone without sacrificing efficiency. Our findings thus offer a simple mechanism for how efficient IFT is achieved across diverse organisms despite being carried out by motors with different properties.
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Affiliation(s)
- Punam Sonar
- Physik Department E22, Technische Universität München, Garching 85748, Germany
| | - Wiphu Youyen
- Department of Physics, Worcester Polytechnic Institute, 100 Institute Road, Worcester, MA 01609, USA
| | - Augustine Cleetus
- Physik Department E22, Technische Universität München, Garching 85748, Germany
| | | | - Sayed I Mousavi
- Department of Physics, Worcester Polytechnic Institute, 100 Institute Road, Worcester, MA 01609, USA
| | - Willi L Stepp
- Physik Department E22, Technische Universität München, Garching 85748, Germany
| | - William O Hancock
- Department of Biomedical Engineering, Pennsylvania State University, University Park, PA 16802, USA
| | - Erkan Tüzel
- Bioengineering Department, College of Engineering, Temple University, Philadelphia, PA 19122, USA
| | - Zeynep Ökten
- Physik Department E22, Technische Universität München, Garching 85748, Germany.
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33
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Zhang L, Zhen J, Huang Q, Liu H, Li W, Zhang S, Min J, Li Y, Shi L, Woods J, Chen X, Shi Y, Liu Y, Hess RA, Song S, Zhang Z. Mouse spermatogenesis-associated protein 1 (SPATA1), an IFT20 binding partner, is an acrosomal protein. Dev Dyn 2020; 249:543-555. [PMID: 31816150 DOI: 10.1002/dvdy.141] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 11/16/2019] [Accepted: 11/18/2019] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Intraflagellar transport is a motor-driven trafficking system that is required for the formation of cilia. Intraflagellar transport protein 20 (IFT20) is a master regulator for the control of spermatogenesis and male fertility in mice. However, the mechanism of how IFT20 regulates spermatogenesis is unknown. RESULTS Spermatogenesis associated 1 (SPATA1) was identified to be a major potential binding partner of IFT20 by a yeast two-hybrid screening. The interaction between SPATA1 and IFT20 was examined by direct yeast two-hybrid, co-localization, and co-immunoprecipitation assays. SPATA1 is highly abundant in the mouse testis, and is also expressed in the heart and kidney. During the first wave of spermatogenesis, SPATA1 is detectable at postnatal day 24 and its expression is increased at day 30 and 35. Immunofluorescence staining of mouse testis sections and epididymal sperm demonstrated that SPATA1 is localized mainly in the acrosome of developing spermatids but not in epididymal sperm. IFT20 is also present in the acrosome area of round spermatids. In conditional Ift20 knockout mice, testicular expression level and acrosomal localization of SPATA1 are not changed. CONCLUSIONS SPATA1 is an IFT20 binding protein and may provide a docking site for IFT20 complex binding to the acrosome area.
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Affiliation(s)
- Ling Zhang
- Department of Occupational and Environmental Health, Hubei Province Key Laboratory of Occupational Hazard Identification and Control, School of Public Health, Wuhan University of Science and Technology, Wuhan, China
| | - Jingkai Zhen
- Department of Occupational and Environmental Health, Hubei Province Key Laboratory of Occupational Hazard Identification and Control, School of Public Health, Wuhan University of Science and Technology, Wuhan, China
| | - Qian Huang
- Department of Occupational and Environmental Health, Hubei Province Key Laboratory of Occupational Hazard Identification and Control, School of Public Health, Wuhan University of Science and Technology, Wuhan, China.,Department of Physiology, Wayne State University, Detroit, Michigan
| | - Hong Liu
- Department of Occupational and Environmental Health, Hubei Province Key Laboratory of Occupational Hazard Identification and Control, School of Public Health, Wuhan University of Science and Technology, Wuhan, China.,Department of Physiology, Wayne State University, Detroit, Michigan
| | - Wei Li
- Department of Physiology, Wayne State University, Detroit, Michigan
| | - Shiyang Zhang
- Department of Occupational and Environmental Health, Hubei Province Key Laboratory of Occupational Hazard Identification and Control, School of Public Health, Wuhan University of Science and Technology, Wuhan, China.,Department of Physiology, Wayne State University, Detroit, Michigan
| | - Jie Min
- Department of Occupational and Environmental Health, Hubei Province Key Laboratory of Occupational Hazard Identification and Control, School of Public Health, Wuhan University of Science and Technology, Wuhan, China
| | - Yuhong Li
- Department of Occupational and Environmental Health, Hubei Province Key Laboratory of Occupational Hazard Identification and Control, School of Public Health, Wuhan University of Science and Technology, Wuhan, China.,Department of Physiology, Wayne State University, Detroit, Michigan
| | - Lin Shi
- Department of Occupational and Environmental Health, Hubei Province Key Laboratory of Occupational Hazard Identification and Control, School of Public Health, Wuhan University of Science and Technology, Wuhan, China.,Department of Physiology, Wayne State University, Detroit, Michigan
| | - James Woods
- Department of Physiology, Wayne State University, Detroit, Michigan
| | - Xuequn Chen
- Department of Physiology, Wayne State University, Detroit, Michigan
| | - Yuqin Shi
- Department of Occupational and Environmental Health, Hubei Province Key Laboratory of Occupational Hazard Identification and Control, School of Public Health, Wuhan University of Science and Technology, Wuhan, China
| | - Yunhao Liu
- Department of Occupational and Environmental Health, Hubei Province Key Laboratory of Occupational Hazard Identification and Control, School of Public Health, Wuhan University of Science and Technology, Wuhan, China
| | - Rex A Hess
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois, Urbana, Illinois
| | - Shizhen Song
- Department of Occupational and Environmental Health, Hubei Province Key Laboratory of Occupational Hazard Identification and Control, School of Public Health, Wuhan University of Science and Technology, Wuhan, China
| | - Zhibing Zhang
- Department of Physiology, Wayne State University, Detroit, Michigan.,Department of Obstetrics and Gynecology, Wayne State University, Detroit, Michigan
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34
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Dutta R, Sarkar SR. Role of Dynein and Dynactin (DCTN-1) in Neurodegenerative Diseases. ACTA ACUST UNITED AC 2019. [DOI: 10.33805/2641-8991.123] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The pathophysiology and concept of degeneration in central nervous system is very complex and overwhelming at times. There is a complex mechanism which exists among different molecules in the cytoplasm of cell bodies of neurons, antegrade and retrograde axonal transport of cargoes and accumulation of certain substances and proteins which can influence the excitatory neurotransmitter like glutamate initiating the process of neurodegeneration. Neurons have extensive processes and communication between those processes and the cell body is crucial to neuronal function, viability and survival over time with progression of age. Researchers believe neurons are uniquely dependent on microtubule-based cargo transport. There is enough evidence to support that deficits in retrograde axonal transport contribute to pathogenesis in multiple neurodegenerative diseases. Cytoplasmic dynein and its regulation by Dynactin (DCTN1) is the major molecular motor cargo involved in autophagy, mitosis and neuronal cell survival. Mutation in dynactin gene located in 2p13.1,is indeed studied very extensively and is considered to be involved directly or indirectly to various conditions like Perry syndrome, familial and sporadic Amyotrophic lateral sclerosis, Hereditary spastic paraplegia, Spinocerebellar Ataxia (SCA-5), Huntingtons disease, Alzheimers disease, Charcot marie tooth disease, Hereditary motor neuropathy 7B, prion disease, parkinsons disease, malformation of cortical development, polymicrogyria to name a few with exception of Multiple Sclerosis (MS).
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35
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Abstract
Primary cilia project in a single copy from the surface of most vertebrate cell types; they detect and transmit extracellular cues to regulate diverse cellular processes during development and to maintain tissue homeostasis. The sensory capacity of primary cilia relies on the coordinated trafficking and temporal localization of specific receptors and associated signal transduction modules in the cilium. The canonical Hedgehog (HH) pathway, for example, is a bona fide ciliary signalling system that regulates cell fate and self-renewal in development and tissue homeostasis. Specific receptors and associated signal transduction proteins can also localize to primary cilia in a cell type-dependent manner; available evidence suggests that the ciliary constellation of these proteins can temporally change to allow the cell to adapt to specific developmental and homeostatic cues. Consistent with important roles for primary cilia in signalling, mutations that lead to their dysfunction underlie a pleiotropic group of diseases and syndromic disorders termed ciliopathies, which affect many different tissues and organs of the body. In this Review, we highlight central mechanisms by which primary cilia coordinate HH, G protein-coupled receptor, WNT, receptor tyrosine kinase and transforming growth factor-β (TGFβ)/bone morphogenetic protein (BMP) signalling and illustrate how defects in the balanced output of ciliary signalling events are coupled to developmental disorders and disease progression.
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36
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Structure of the dynein-2 complex and its assembly with intraflagellar transport trains. Nat Struct Mol Biol 2019; 26:823-829. [PMID: 31451806 PMCID: PMC6774794 DOI: 10.1038/s41594-019-0286-y] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 07/24/2019] [Indexed: 12/12/2022]
Abstract
Dynein-2 assembles with polymeric intraflagellar transport (IFT) trains to form a transport machinery that is crucial for cilia biogenesis and signaling. Here we recombinantly expressed the ~1.4-MDa human dynein-2 complex and solved its cryo-EM structure to near-atomic resolution. The two identical copies of the dynein-2 heavy chain are contorted into different conformations by a WDR60-WDR34 heterodimer and a block of two RB and six LC8 light chains. One heavy chain is steered into a zig-zag conformation, which matches the periodicity of the anterograde IFT-B train. Contacts between adjacent dyneins along the train indicate a cooperative mode of assembly. Removal of the WDR60-WDR34-light chain subcomplex renders dynein-2 monomeric and relieves autoinhibition of its motility. Our results converge on a model in which an unusual stoichiometry of non-motor subunits controls dynein-2 assembly, asymmetry, and activity, giving mechanistic insight into the interaction of dynein-2 with IFT trains and the origin of diverse functions in the dynein family.
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37
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Jiang YY, Maier W, Baumeister R, Minevich G, Joachimiak E, Wloga D, Ruan Z, Kannan N, Bocarro S, Bahraini A, Vasudevan KK, Lechtreck K, Orias E, Gaertig J. LF4/MOK and a CDK-related kinase regulate the number and length of cilia in Tetrahymena. PLoS Genet 2019; 15:e1008099. [PMID: 31339880 PMCID: PMC6682161 DOI: 10.1371/journal.pgen.1008099] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 08/05/2019] [Accepted: 06/13/2019] [Indexed: 11/18/2022] Open
Abstract
The length of cilia is controlled by a poorly understood mechanism that involves members of the conserved RCK kinase group, and among them, the LF4/MOK kinases. The multiciliated protist model, Tetrahymena, carries two types of cilia (oral and locomotory) and the length of the locomotory cilia is dependent on their position with the cell. In Tetrahymena, loss of an LF4/MOK ortholog, LF4A, lengthened the locomotory cilia, but also reduced their number. Without LF4A, cilia assembled faster and showed signs of increased intraflagellar transport (IFT). Consistently, overproduced LF4A shortened cilia and downregulated IFT. GFP-tagged LF4A, expressed in the native locus and imaged by total internal reflection microscopy, was enriched at the basal bodies and distributed along the shafts of cilia. Within cilia, most LF4A-GFP particles were immobile and a few either diffused or moved by IFT. We suggest that the distribution of LF4/MOK along the cilium delivers a uniform dose of inhibition to IFT trains that travel from the base to the tip. In a longer cilium, the IFT machinery may experience a higher cumulative dose of inhibition by LF4/MOK. Thus, LF4/MOK activity could be a readout of cilium length that helps to balance the rate of IFT-driven assembly with the rate of disassembly at steady state. We used a forward genetic screen to identify a CDK-related kinase, CDKR1, whose loss-of-function suppressed the shortening of cilia caused by overexpression of LF4A, by reducing its kinase activity. Loss of CDKR1 alone lengthened both the locomotory and oral cilia. CDKR1 resembles other known ciliary CDK-related kinases: LF2 of Chlamydomonas, mammalian CCRK and DYF-18 of C. elegans, in lacking the cyclin-binding motif and acting upstream of RCKs. The new genetic tools we developed here for Tetrahymena have potential for further dissection of the principles of cilia length regulation in multiciliated cells.
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Affiliation(s)
- Yu-Yang Jiang
- Department of Cellular Biology, University of Georgia, Athens, Georgia, United States of America
| | - Wolfgang Maier
- Bio 3/Bioinformatics and Molecular Genetics, Faculty of Biology and ZBMZ, Faculty of Medicine, Albert-Ludwigs-University of Freiburg, Freiburg, Germany
| | - Ralf Baumeister
- Bio 3/Bioinformatics and Molecular Genetics, Faculty of Biology and ZBMZ, Faculty of Medicine, Albert-Ludwigs-University of Freiburg, Freiburg, Germany
| | - Gregory Minevich
- Department of Biochemistry and Molecular Biophysics, Columbia University Medical Center, New York, New York, United States of America
| | - Ewa Joachimiak
- Laboratory of Cytoskeleton and Cilia Biology, Nencki Institute of Experimental Biology of Polish Academy of Sciences, Warsaw, Poland
| | - Dorota Wloga
- Laboratory of Cytoskeleton and Cilia Biology, Nencki Institute of Experimental Biology of Polish Academy of Sciences, Warsaw, Poland
| | - Zheng Ruan
- Institute of Bioinformatics, University of Georgia, Athens, Georgia, United States of America
| | - Natarajan Kannan
- Institute of Bioinformatics, University of Georgia, Athens, Georgia, United States of America
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, United States of America
| | - Stephen Bocarro
- Department of Cellular Biology, University of Georgia, Athens, Georgia, United States of America
| | - Anoosh Bahraini
- Department of Cellular Biology, University of Georgia, Athens, Georgia, United States of America
| | - Krishna Kumar Vasudevan
- Department of Cellular Biology, University of Georgia, Athens, Georgia, United States of America
| | - Karl Lechtreck
- Department of Cellular Biology, University of Georgia, Athens, Georgia, United States of America
| | - Eduardo Orias
- Department of Molecular, Cellular and Developmental Biology, University of California Santa Barbara, Santa Barbara, California, United States of America
| | - Jacek Gaertig
- Department of Cellular Biology, University of Georgia, Athens, Georgia, United States of America
- * E-mail:
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38
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Grotjahn DA, Lander GC. Setting the dynein motor in motion: New insights from electron tomography. J Biol Chem 2019; 294:13202-13217. [PMID: 31285262 DOI: 10.1074/jbc.rev119.003095] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Dyneins are ATP-fueled macromolecular machines that power all minus-end microtubule-based transport processes of molecular cargo within eukaryotic cells and play essential roles in a wide variety of cellular functions. These complex and fascinating motors have been the target of countless structural and biophysical studies. These investigations have elucidated the mechanism of ATP-driven force production and have helped unravel the conformational rearrangements associated with the dynein mechanochemical cycle. However, despite decades of research, it remains unknown how these molecular motions are harnessed to power massive cellular reorganization and what are the regulatory mechanisms that drive these processes. Recent advancements in electron tomography imaging have enabled researchers to visualize dynein motors in their transport environment with unprecedented detail and have led to exciting discoveries regarding dynein motor function and regulation. In this review, we will highlight how these recent structural studies have fundamentally propelled our understanding of the dynein motor and have revealed some unexpected, unifying mechanisms of regulation.
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Affiliation(s)
- Danielle A Grotjahn
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California 92037
| | - Gabriel C Lander
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California 92037.
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39
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Jordan MA, Pigino G. In situ cryo-electron tomography and subtomogram averaging of intraflagellar transport trains. Methods Cell Biol 2019; 152:179-195. [PMID: 31326020 DOI: 10.1016/bs.mcb.2019.04.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
In situ cryo-electron tomography (cryo-ET) and subtomogram averaging are powerful tools, able to provide 3D structures of biological samples at sub-nanometer resolution, while preserving information about cellular context and higher-order assembly. Best results are typically achieved, when applied to highly repetitive structures, such as viruses. Other typical examples are protein complexes that decorate long stretches along ciliary microtubules at stereotypical and precise repeats, such as axonemal dyneins. For such cases, a plethora of subtomogram averaging protocols exist. In this chapter, we show how we use cryo-ET and subtomogram averaging to study the architecture of the intraflagellar transport (IFT) machinery, a more challenging target that appears only in low copy numbers per tomogram. In the IFT trains, repeating units of IFT adaptor proteins engage two oppositely directed molecular motors to quickly shuttle ciliary building blocks and other proteins to the tip of the cilium and/or back to the base. This dynamic and sporadic nature of IFT trains poses challenges for determining the localization or precise orientation of the particles to be averaged. Solutions to these problems are described in this chapter.
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Affiliation(s)
- Mareike A Jordan
- Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG), Dresden, Germany
| | - Gaia Pigino
- Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG), Dresden, Germany.
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40
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Wachter S, Jung J, Shafiq S, Basquin J, Fort C, Bastin P, Lorentzen E. Binding of IFT22 to the intraflagellar transport complex is essential for flagellum assembly. EMBO J 2019; 38:embj.2018101251. [PMID: 30940671 DOI: 10.15252/embj.2018101251] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 02/28/2019] [Accepted: 03/04/2019] [Indexed: 01/08/2023] Open
Abstract
Intraflagellar transport (IFT) relies on motor proteins and the IFT complex to construct cilia and flagella. The IFT complex subunit IFT22/RabL5 has sequence similarity with small GTPases although the nucleotide specificity is unclear because of non-conserved G4/G5 motifs. We show that IFT22 specifically associates with G-nucleotides and present crystal structures of IFT22 in complex with GDP, GTP, and with IFT74/81. Our structural analysis unravels an unusual GTP/GDP-binding mode of IFT22 bypassing the classical G4 motif. The GTPase switch regions of IFT22 become ordered upon complex formation with IFT74/81 and mediate most of the IFT22-74/81 interactions. Structure-based mutagenesis reveals that association of IFT22 with the IFT complex is essential for flagellum construction in Trypanosoma brucei although IFT22 GTP-loading is not strictly required.
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Affiliation(s)
- Stefanie Wachter
- Department of Structural Cell Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Jamin Jung
- Trypanosome Cell Biology Unit, Institut Pasteur & INSERM U1201, Paris, France
| | - Shahaan Shafiq
- Trypanosome Cell Biology Unit, Institut Pasteur & INSERM U1201, Paris, France
| | - Jerome Basquin
- Department of Structural Cell Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Cécile Fort
- Trypanosome Cell Biology Unit, Institut Pasteur & INSERM U1201, Paris, France
| | - Philippe Bastin
- Trypanosome Cell Biology Unit, Institut Pasteur & INSERM U1201, Paris, France
| | - Esben Lorentzen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus C, Denmark
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41
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Fabbri L, Bost F, Mazure NM. Primary Cilium in Cancer Hallmarks. Int J Mol Sci 2019; 20:E1336. [PMID: 30884815 PMCID: PMC6471594 DOI: 10.3390/ijms20061336] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 02/28/2019] [Accepted: 03/11/2019] [Indexed: 12/12/2022] Open
Abstract
The primary cilium is a solitary, nonmotile and transitory appendage that is present in virtually all mammalian cells. Our knowledge of its ultrastructure and function is the result of more than fifty years of research that has dramatically changed our perspectives on the primary cilium. The mutual regulation between ciliogenesis and the cell cycle is now well-recognized, as well as the function of the primary cilium as a cellular "antenna" for perceiving external stimuli, such as light, odorants, and fluids. By displaying receptors and signaling molecules, the primary cilium is also a key coordinator of signaling pathways that converts extracellular cues into cellular responses. Given its critical tasks, any defects in primary cilium formation or function lead to a wide spectrum of diseases collectively called "ciliopathies". An emerging role of primary cilium is in the regulation of cancer development. In this review, we seek to describe the current knowledge about the influence of the primary cilium in cancer progression, with a focus on some of the events that cancers need to face to sustain survival and growth in hypoxic microenvironment: the cancer hallmarks.
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Affiliation(s)
- Lucilla Fabbri
- Université Côte d'Azur (UCA), INSERM U1065, C3M, 151 Route de St Antoine de Ginestière, BP2 3194, 06204 Nice, France.
| | - Frédéric Bost
- Université Côte d'Azur (UCA), INSERM U1065, C3M, 151 Route de St Antoine de Ginestière, BP2 3194, 06204 Nice, France.
| | - Nathalie M Mazure
- Université Côte d'Azur (UCA), INSERM U1065, C3M, 151 Route de St Antoine de Ginestière, BP2 3194, 06204 Nice, France.
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42
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Cilia Distal Domain: Diversity in Evolutionarily Conserved Structures. Cells 2019; 8:cells8020160. [PMID: 30769894 PMCID: PMC6406257 DOI: 10.3390/cells8020160] [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: 12/30/2018] [Revised: 01/25/2019] [Accepted: 02/13/2019] [Indexed: 12/12/2022] Open
Abstract
Eukaryotic cilia are microtubule-based organelles that protrude from the cell surface to fulfill sensory and motility functions. Their basic structure consists of an axoneme templated by a centriole/basal body. Striking differences in ciliary ultra-structures can be found at the ciliary base, the axoneme and the tip, not only throughout the eukaryotic tree of life, but within a single organism. Defects in cilia biogenesis and function are at the origin of human ciliopathies. This structural/functional diversity and its relationship with the etiology of these diseases is poorly understood. Some of the important events in cilia function occur at their distal domain, including cilia assembly/disassembly, IFT (intraflagellar transport) complexes' remodeling, and signal detection/transduction. How axonemal microtubules end at this domain varies with distinct cilia types, originating different tip architectures. Additionally, they show a high degree of dynamic behavior and are able to respond to different stimuli. The existence of microtubule-capping structures (caps) in certain types of cilia contributes to this diversity. It has been proposed that caps play a role in axoneme length control and stabilization, but their roles are still poorly understood. Here, we review the current knowledge on cilia structure diversity with a focus on the cilia distal domain and caps and discuss how they affect cilia structure and function.
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43
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Jensen VL, Lambacher NJ, Li C, Mohan S, Williams CL, Inglis PN, Yoder BK, Blacque OE, Leroux MR. Role for intraflagellar transport in building a functional transition zone. EMBO Rep 2018; 19:e45862. [PMID: 30429209 PMCID: PMC6280794 DOI: 10.15252/embr.201845862] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 10/22/2018] [Accepted: 10/26/2018] [Indexed: 12/21/2022] Open
Abstract
Genetic disorders caused by cilia dysfunction, termed ciliopathies, frequently involve the intraflagellar transport (IFT) system. Mutations in IFT subunits-including IFT-dynein motor DYNC2H1-impair ciliary structures and Hedgehog signalling, typically leading to "skeletal" ciliopathies such as Jeune asphyxiating thoracic dystrophy. Intriguingly, IFT gene mutations also cause eye, kidney and brain ciliopathies often linked to defects in the transition zone (TZ), a ciliary gate implicated in Hedgehog signalling. Here, we identify a C. elegans temperature-sensitive (ts) IFT-dynein mutant (che-3; human DYNC2H1) and use it to show a role for retrograde IFT in anterograde transport and ciliary maintenance. Unexpectedly, correct TZ assembly and gating function for periciliary proteins also require IFT-dynein. Using the reversibility of the novel ts-IFT-dynein, we show that restoring IFT in adults (post-developmentally) reverses defects in ciliary structure, TZ protein localisation and ciliary gating. Notably, this ability to reverse TZ defects declines as animals age. Together, our findings reveal a previously unknown role for IFT in TZ assembly in metazoans, providing new insights into the pathomechanism and potential phenotypic overlap between IFT- and TZ-associated ciliopathies.
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Affiliation(s)
- Victor L Jensen
- Department of Molecular Biology and Biochemistry, and Centre for Cell Biology, Development and Disease, Simon Fraser University, Burnaby, BC, Canada
| | - Nils J Lambacher
- Department of Molecular Biology and Biochemistry, and Centre for Cell Biology, Development and Disease, Simon Fraser University, Burnaby, BC, Canada
| | - Chunmei Li
- Department of Molecular Biology and Biochemistry, and Centre for Cell Biology, Development and Disease, Simon Fraser University, Burnaby, BC, Canada
| | - Swetha Mohan
- Department of Molecular Biology and Biochemistry, and Centre for Cell Biology, Development and Disease, Simon Fraser University, Burnaby, BC, Canada
| | - Corey L Williams
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham Medical School, Birmingham, AL, USA
| | - Peter N Inglis
- Department of Biology, Kwantlen Polytechnic University, Surrey, BC, Canada
| | - Bradley K Yoder
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham Medical School, Birmingham, AL, USA
| | - Oliver E Blacque
- School of Biomolecular and Biomedical Science, University College Dublin, Belfield, Dublin 4, Ireland
| | - Michel R Leroux
- Department of Molecular Biology and Biochemistry, and Centre for Cell Biology, Development and Disease, Simon Fraser University, Burnaby, BC, Canada
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44
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Jordan MA, Diener DR, Stepanek L, Pigino G. The cryo-EM structure of intraflagellar transport trains reveals how dynein is inactivated to ensure unidirectional anterograde movement in cilia. Nat Cell Biol 2018; 20:1250-1255. [PMID: 30323187 DOI: 10.1038/s41556-018-0213-1] [Citation(s) in RCA: 100] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2018] [Accepted: 09/11/2018] [Indexed: 02/03/2023]
Abstract
Movement of cargos along microtubules plays key roles in diverse cellular processes, from signalling to mitosis. In cilia, rapid movement of ciliary components along the microtubules to and from the assembly site is essential for the assembly and disassembly of the structure itself1. This bidirectional transport, known as intraflagellar transport (IFT)2, is driven by the anterograde motor kinesin-23 and the retrograde motor dynein-1b (dynein-2 in mammals)4,5. However, to drive retrograde transport, dynein-1b must first be delivered to the ciliary tip by anterograde IFT6. Although, the presence of opposing motors in bidirectional transport processes often leads to periodic stalling and slowing of cargos7, IFT is highly processive1,2,8. Using cryo-electron tomography, we show that a tug-of-war between kinesin-2 and dynein-1b is prevented by loading dynein-1b onto anterograde IFT trains in an autoinhibited form and by positioning it away from the microtubule track to prevent binding. Once at the ciliary tip, dynein-1b must transition into an active form and engage microtubules to power retrograde trains. These findings provide a striking example of how coordinated structural changes mediate the behaviour of complex cellular machinery.
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Affiliation(s)
- Mareike A Jordan
- Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG), Dresden, Germany
| | - Dennis R Diener
- Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG), Dresden, Germany
| | - Ludek Stepanek
- Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG), Dresden, Germany
| | - Gaia Pigino
- Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG), Dresden, Germany.
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45
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Roberts AJ. Emerging mechanisms of dynein transport in the cytoplasm versus the cilium. Biochem Soc Trans 2018; 46:967-982. [PMID: 30065109 PMCID: PMC6103457 DOI: 10.1042/bst20170568] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2018] [Revised: 06/13/2018] [Accepted: 06/18/2018] [Indexed: 02/08/2023]
Abstract
Two classes of dynein power long-distance cargo transport in different cellular contexts. Cytoplasmic dynein-1 is responsible for the majority of transport toward microtubule minus ends in the cell interior. Dynein-2, also known as intraflagellar transport dynein, moves cargoes along the axoneme of eukaryotic cilia and flagella. Both dyneins operate as large ATP-driven motor complexes, whose dysfunction is associated with a group of human disorders. But how similar are their mechanisms of action and regulation? To examine this question, this review focuses on recent advances in dynein-1 and -2 research, and probes to what extent the emerging principles of dynein-1 transport could apply to or differ from those of the less well-understood dynein-2 mechanoenzyme.
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Affiliation(s)
- Anthony J Roberts
- Institute of Structural and Molecular Biology, Birkbeck, University of London, Malet Street, London, U.K.
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46
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Abstract
Cytoplasmic dynein 1 is an important microtubule-based motor in many eukaryotic cells. Dynein has critical roles both in interphase and during cell division. Here, we focus on interphase cargoes of dynein, which include membrane-bound organelles, RNAs, protein complexes and viruses. A central challenge in the field is to understand how a single motor can transport such a diverse array of cargoes and how this process is regulated. The molecular basis by which each cargo is linked to dynein and its cofactor dynactin has started to emerge. Of particular importance for this process is a set of coiled-coil proteins - activating adaptors - that both recruit dynein-dynactin to their cargoes and activate dynein motility.
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47
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Zhang Y, Liu H, Li W, Zhang Z, Zhang S, Teves ME, Stevens C, Foster JA, Campbell GE, Windle JJ, Hess RA, Pazour GJ, Zhang Z. Intraflagellar transporter protein 140 (IFT140), a component of IFT-A complex, is essential for male fertility and spermiogenesis in mice. Cytoskeleton (Hoboken) 2018; 75:70-84. [PMID: 29236364 DOI: 10.1002/cm.21427] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Revised: 11/16/2017] [Accepted: 11/20/2017] [Indexed: 11/11/2022]
Abstract
Intraflagellar transport (IFT) is a conserved mechanism essential for the assembly and maintenance of most eukaryotic cilia and flagella. However, little is known about its role in sperm flagella formation and male fertility. IFT140 is a component of IFT-A complex. In mouse, it is highly expressed in the testis. Ift140 gene was inactivated specifically in mouse spermatocytes/spermatids. The mutant mice did not show any gross abnormalities, but all were infertile and associated with significantly reduced sperm number and motility. Multiple sperm morphological abnormalities were discovered, including amorphous heads, short/bent flagella and swollen tail tips, as well as vesicles along the flagella due to spermiogenesis defects. The epididymides contained round bodies of cytoplasm derived from the sloughing of the cytoplasmic lobes and residual bodies. Knockout of Ift140 did not significantly affect testicular expression levels of selective IFT components but localization of IFT27 and IFT88, two components of IFT-B complex, was changed. Our findings demonstrate that IFT140 is a key regulator for male fertility and normal spermiogenesis in mice. It not only plays a role in sperm flagella assembling, but is also involved in critical assembly of proteins that interface between the germ cell plasma and the Sertoli cell.
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Affiliation(s)
- Yong Zhang
- Department of Dermatology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.,Department of Obstetrics & Gynecology, Virginia Commonwealth University, Richmond, Virginia 23298
| | - Hong Liu
- Department of Obstetrics & Gynecology, Virginia Commonwealth University, Richmond, Virginia 23298.,School of Public Health, Wuhan University of Science and Technology, Wuhan 430060, Hubei
| | - Wei Li
- Department of Obstetrics & Gynecology, Virginia Commonwealth University, Richmond, Virginia 23298
| | - Zhengang Zhang
- Department of Obstetrics & Gynecology, Virginia Commonwealth University, Richmond, Virginia 23298.,Department of Gastroenterology, Tongji Hospital Affiliated to Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei
| | - Shiyang Zhang
- Department of Obstetrics & Gynecology, Virginia Commonwealth University, Richmond, Virginia 23298.,School of Public Health, Wuhan University of Science and Technology, Wuhan 430060, Hubei
| | - Maria E Teves
- Department of Obstetrics & Gynecology, Virginia Commonwealth University, Richmond, Virginia 23298
| | - Courtney Stevens
- Department of Biology, Randolph-Macon College, Ashland, Virginia 23005
| | - James A Foster
- Department of Biology, Randolph-Macon College, Ashland, Virginia 23005
| | - Gregory E Campbell
- Department of Human and Molecular Genetics, Virginia Commonwealth University, Richmond, Virginia 23298
| | - Jolene J Windle
- Department of Human and Molecular Genetics, Virginia Commonwealth University, Richmond, Virginia 23298
| | - Rex A Hess
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois, 2001 S. Lincoln, Urbana, Illinois 61802-6199
| | - Gregory J Pazour
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Zhibing Zhang
- Department of Obstetrics & Gynecology, Virginia Commonwealth University, Richmond, Virginia 23298.,School of Public Health, Wuhan University of Science and Technology, Wuhan 430060, Hubei
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48
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Dong B, Wu S, Wang J, Liu YX, Peng Z, Meng DM, Huang K, Wu M, Fan ZC. Chlamydomonas IFT25 is dispensable for flagellar assembly but required to export the BBSome from flagella. Biol Open 2017; 6:1680-1691. [PMID: 28838966 PMCID: PMC5703605 DOI: 10.1242/bio.026278] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Intraflagellar transport (IFT) particles are composed of polyprotein complexes IFT-A and IFT-B as well as cargo adaptors such as the BBSome. Two IFT-B subunits, IFT25 and IFT27 were found to form a heterodimer, which is essential in exporting the BBSome out of the cilium but not involved in flagellar assembly and cytokinesis in vertebrates. Controversial results were, however, recorded to show that defects in IFT, flagellar assembly and even cytokinesis were caused by IFT27 knockdown in Chlamydomonas reinhardtii. Using C. reinhardtii as a model organism, we report that depletion of IFT25 has no effect on flagellar assembly and does not affect the entry of the BBSome into the flagellum, but IFT25 depletion did impair BBSome movement out of the flagellum, clarifying the evolutionally conserved role of IFT25 in regulating the exit of the BBSome from the flagellum cross species. Interestingly, depletion of IFT25 causes dramatic reduction of IFT27 as expected, which does not cause defects in flagellar assembly and cytokinesis in C. reinhardtii. Our data thus support that Chlamydomonas IFT27, like its vertebrate homologues, is not involved in flagellar assembly and cytokinesis. Summary: Chlamydomonas IFT25 is not involved in flagellar assembly, but is required for export of the BBSome from the flagellum.
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Affiliation(s)
- Bin Dong
- Key Laboratory of Food Nutrition and Safety, Ministry of Education of China, Institute of Health Biotechnology, International Collaborative Research Center for Health Biotechnology, College of Food Engineering and Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, People's Republic of China
| | - Song Wu
- Key Laboratory of Food Nutrition and Safety, Ministry of Education of China, Institute of Health Biotechnology, International Collaborative Research Center for Health Biotechnology, College of Food Engineering and Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, People's Republic of China
| | - Jing Wang
- Key Laboratory of Food Nutrition and Safety, Ministry of Education of China, Institute of Health Biotechnology, International Collaborative Research Center for Health Biotechnology, College of Food Engineering and Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, People's Republic of China
| | - Yan-Xia Liu
- Key Laboratory of Food Nutrition and Safety, Ministry of Education of China, Institute of Health Biotechnology, International Collaborative Research Center for Health Biotechnology, College of Food Engineering and Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, People's Republic of China
| | - Zhao Peng
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, 430072, People's Republic of China
| | - De-Mei Meng
- Key Laboratory of Food Nutrition and Safety, Ministry of Education of China, Institute of Health Biotechnology, International Collaborative Research Center for Health Biotechnology, College of Food Engineering and Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, People's Republic of China
| | - Kaiyao Huang
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, 430072, People's Republic of China
| | - Mingfu Wu
- Cardiovascular Science Center, Albany Medical College, Albany, New York 12208, USA
| | - Zhen-Chuan Fan
- Key Laboratory of Food Nutrition and Safety, Ministry of Education of China, Institute of Health Biotechnology, International Collaborative Research Center for Health Biotechnology, College of Food Engineering and Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, People's Republic of China .,Obesita & Algaegen LLC, College Station, Texas 77845, USA
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49
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Chien A, Shih SM, Bower R, Tritschler D, Porter ME, Yildiz A. Dynamics of the IFT machinery at the ciliary tip. eLife 2017; 6:28606. [PMID: 28930071 PMCID: PMC5662288 DOI: 10.7554/elife.28606] [Citation(s) in RCA: 88] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Accepted: 09/12/2017] [Indexed: 12/15/2022] Open
Abstract
Intraflagellar transport (IFT) is essential for the elongation and maintenance of eukaryotic cilia and flagella. Due to the traffic jam of multiple trains at the ciliary tip, how IFT trains are remodeled in these turnaround zones cannot be determined by conventional imaging. Using PhotoGate, we visualized the full range of movement of single IFT trains and motors in Chlamydomonas flagella. Anterograde trains split apart and IFT complexes mix with each other at the tip to assemble retrograde trains. Dynein-1b is carried to the tip by kinesin-II as inactive cargo on anterograde trains. Unlike dynein-1b, kinesin-II detaches from IFT trains at the tip and diffuses in flagella. As the flagellum grows longer, diffusion delays return of kinesin-II to the basal body, depleting kinesin-II available for anterograde transport. Our results suggest that dissociation of kinesin-II from IFT trains serves as a negative feedback mechanism that facilitates flagellar length control in Chlamydomonas.
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Affiliation(s)
- Alexander Chien
- Biophysics Graduate Group, University of California, Berkeley, Berkeley, United States
| | - Sheng Min Shih
- Physics Department, University of California, Berkeley, Berkeley, United States
| | - Raqual Bower
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, United States
| | - Douglas Tritschler
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, United States
| | - Mary E Porter
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, United States
| | - Ahmet Yildiz
- Biophysics Graduate Group, University of California, Berkeley, Berkeley, United States.,Physics Department, University of California, Berkeley, Berkeley, United States.,Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
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50
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Stepp WL, Merck G, Mueller-Planitz F, Ökten Z. Kinesin-2 motors adapt their stepping behavior for processive transport on axonemes and microtubules. EMBO Rep 2017; 18:1947-1956. [PMID: 28887322 DOI: 10.15252/embr.201744097] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Revised: 08/11/2017] [Accepted: 08/14/2017] [Indexed: 11/09/2022] Open
Abstract
Two structurally distinct filamentous tracks, namely singlet microtubules in the cytoplasm and axonemes in the cilium, serve as railroads for long-range transport processes in vivo In all organisms studied so far, the kinesin-2 family is essential for long-range transport on axonemes. Intriguingly, in higher eukaryotes, kinesin-2 has been adapted to work on microtubules in the cytoplasm as well. Here, we show that heterodimeric kinesin-2 motors distinguish between axonemes and microtubules. Unlike canonical kinesin-1, kinesin-2 takes directional, off-axis steps on microtubules, but it resumes a straight path when walking on the axonemes. The inherent ability of kinesin-2 to side-track on the microtubule lattice restricts the motor to one side of the doublet microtubule in axonemes. The mechanistic features revealed here provide a molecular explanation for the previously observed partitioning of oppositely moving intraflagellar transport trains to the A- and B-tubules of the same doublet microtubule. Our results offer first mechanistic insights into why nature may have co-evolved the heterodimeric kinesin-2 with the ciliary machinery to work on the specialized axonemal surface for two-way traffic.
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Affiliation(s)
- Willi L Stepp
- Physik Department E22, Technische Universität München, Garching, Germany
| | - Georg Merck
- Physik Department E22, Technische Universität München, Garching, Germany
| | - Felix Mueller-Planitz
- Molecular Biology, Biomedical Center, Faculty of Medicine, LMU Munich, Martinsried, Germany
| | - Zeynep Ökten
- Physik Department E22, Technische Universität München, Garching, Germany .,Munich Center for Integrated Protein Science, Munich, Germany
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