51
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Morthorst SK, Christensen ST, Pedersen LB. Regulation of ciliary membrane protein trafficking and signalling by kinesin motor proteins. FEBS J 2018; 285:4535-4564. [PMID: 29894023 DOI: 10.1111/febs.14583] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 05/09/2018] [Accepted: 06/11/2018] [Indexed: 12/14/2022]
Abstract
Primary cilia are antenna-like sensory organelles that regulate a substantial number of cellular signalling pathways in vertebrates, both during embryonic development as well as in adulthood, and mutations in genes coding for ciliary proteins are causative of an expanding group of pleiotropic diseases known as ciliopathies. Cilia consist of a microtubule-based axoneme core, which is subtended by a basal body and covered by a bilayer lipid membrane of unique protein and lipid composition. Cilia are dynamic organelles, and the ability of cells to regulate ciliary protein and lipid content in response to specific cellular and environmental cues is crucial for balancing ciliary signalling output. Here we discuss mechanisms involved in regulation of ciliary membrane protein trafficking and signalling, with main focus on kinesin-2 and kinesin-3 family members.
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52
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Taschner M, Lorentzen A, Mourão A, Collins T, Freke GM, Moulding D, Basquin J, Jenkins D, Lorentzen E. Crystal structure of intraflagellar transport protein 80 reveals a homo-dimer required for ciliogenesis. eLife 2018; 7:33067. [PMID: 29658880 PMCID: PMC5931796 DOI: 10.7554/elife.33067] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 04/13/2018] [Indexed: 12/16/2022] Open
Abstract
Oligomeric assemblies of intraflagellar transport (IFT) particles build cilia through sequential recruitment and transport of ciliary cargo proteins within cilia. Here we present the 1.8 Å resolution crystal structure of the Chlamydomonas IFT-B protein IFT80, which reveals the architecture of two N-terminal β-propellers followed by an α-helical extension. The N-terminal β-propeller tethers IFT80 to the IFT-B complex via IFT38 whereas the second β-propeller and the C-terminal α-helical extension result in IFT80 homo-dimerization. Using CRISPR/Cas to create biallelic Ift80 frameshift mutations in IMCD3 mouse cells, we demonstrate that IFT80 is absolutely required for ciliogenesis. Structural mapping and rescue experiments reveal that human disease-causing missense mutations do not cluster within IFT80 and form functional IFT particles. Unlike missense mutant forms of IFT80, deletion of the C-terminal dimerization domain prevented rescue of ciliogenesis. Taken together our results may provide a first insight into higher order IFT complex formation likely required for IFT train formation.
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Affiliation(s)
- Michael Taschner
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Anna Lorentzen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - André Mourão
- Institute of Structural Biology, Helmholtz Zentrum München, Neuherberg, Germany
| | - Toby Collins
- Genetics and Genomic Medicine, University College London, London, United Kingdom
| | - Grace M Freke
- Genetics and Genomic Medicine, University College London, London, United Kingdom
| | - Dale Moulding
- Developmental Biology and Cancer Programmes, Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
| | - Jerome Basquin
- Department of Structural Cell Biology, Max-Planck-Institute of Biochemistry, Martinsried, Germany
| | - Dagan Jenkins
- Genetics and Genomic Medicine, University College London, London, United Kingdom
| | - Esben Lorentzen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
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53
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Nachury MV. The molecular machines that traffic signaling receptors into and out of cilia. Curr Opin Cell Biol 2018; 51:124-131. [PMID: 29579578 PMCID: PMC5949257 DOI: 10.1016/j.ceb.2018.03.004] [Citation(s) in RCA: 113] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 03/06/2018] [Accepted: 03/08/2018] [Indexed: 12/12/2022]
Abstract
Cilia are surface-exposed organelles that dynamically concentrate signaling molecules to organize sensory, developmental and homeostatic pathways. Entry and exit of signaling receptors is germane to the processing of signals and the molecular machines for entry and exit have started to emerge. The IFT-A complex and its membrane recruitment factor Tulp3 complex promotes the entry of signaling receptors into cilia while the BBSome and its membrane recruitment factor Arl6GTP ferry activated signaling receptors out of cilia. Ciliary exit is a surprisingly complex process entailing passage through a first diffusion barrier at the transition zone, diffusion inside an intermediate compartment and crossing of a periciliary diffusion barrier. The two barriers may organize a privileged compartment where activated signaling receptors transiently reside.
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Affiliation(s)
- Maxence V Nachury
- UCSF School of Medicine, Department of Ophthalmology, United States.
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54
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Scheidel N, Kennedy J, Blacque OE. Endosome maturation factors Rabenosyn-5/VPS45 and caveolin-1 regulate ciliary membrane and polycystin-2 homeostasis. EMBO J 2018; 37:embj.201798248. [PMID: 29572244 DOI: 10.15252/embj.201798248] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 02/08/2018] [Accepted: 02/16/2018] [Indexed: 12/24/2022] Open
Abstract
Primary cilium structure and function relies on control of ciliary membrane homeostasis, regulated by membrane trafficking processes that deliver and retrieve ciliary components at the periciliary membrane. However, the molecular mechanisms controlling ciliary membrane establishment and maintenance, especially in relation to endocytosis, remain poorly understood. Here, using Caenorhabditis elegans, we describe closely linked functions for early endosome (EE) maturation factors RABS-5 (Rabenosyn-5) and VPS-45 (VPS45) in regulating cilium length and morphology, ciliary and periciliary membrane volume, and ciliary signalling-related sensory behaviour. We demonstrate that RABS-5 and VPS-45 control periciliary vesicle number and levels of select EE/endocytic markers (WDFY-2, CAV-1) and the ciliopathy membrane receptor PKD-2 (polycystin-2). Moreover, we show that CAV-1 (caveolin-1) also controls PKD-2 ciliary levels and associated sensory behaviour. These data link RABS-5 and VPS-45 ciliary functions to the processing of periciliary-derived endocytic vesicles and regulation of ciliary membrane homeostasis. Our findings also provide insight into the regulation of PKD-2 ciliary levels via integrated endosomal sorting and CAV-1-mediated endocytosis.
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Affiliation(s)
- Noémie Scheidel
- UCD School of Biomolecular and Biomedical Science, University College Dublin, Dublin 4, Ireland
| | - Julie Kennedy
- UCD School of Biomolecular and Biomedical Science, University College Dublin, Dublin 4, Ireland
| | - Oliver E Blacque
- UCD School of Biomolecular and Biomedical Science, University College Dublin, Dublin 4, Ireland
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55
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Arensdorf AM, Dillard ME, Menke JM, Frank MW, Rock CO, Ogden SK. Sonic Hedgehog Activates Phospholipase A2 to Enhance Smoothened Ciliary Translocation. Cell Rep 2018; 19:2074-2087. [PMID: 28591579 DOI: 10.1016/j.celrep.2017.05.033] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 03/30/2017] [Accepted: 05/09/2017] [Indexed: 12/21/2022] Open
Abstract
The G protein-coupled receptor Smoothened (Smo) is the signal transducer of the Sonic Hedgehog (Shh) pathway. Smo signals through G protein-dependent and -independent routes, with G protein-independent canonical signaling to Gli effectors requiring Smo accumulation in the primary cilium. The mechanisms controlling Smo activation and trafficking are not yet clear but likely entail small-molecule binding to pockets in its extracellular cysteine-rich domain (CRD) and/or transmembrane bundle. Here, we demonstrate that the cytosolic phospholipase cPLA2α is activated through Gβγ downstream of Smo to release arachidonic acid. Arachidonic acid binds Smo and synergizes with CRD-binding agonists, promoting Smo ciliary trafficking and high-level signaling. Chemical or genetic cPLA2α inhibition dampens Smo signaling to Gli, revealing an unexpected contribution of G protein-dependent signaling to canonical pathway activity. Arachidonic acid displaces the Smo transmembrane domain inhibitor cyclopamine to rescue CRD agonist-induced signaling, suggesting that arachidonic acid may target the transmembrane bundle to allosterically enhance signaling by CRD agonist-bound Smo.
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Affiliation(s)
- Angela M Arensdorf
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Miriam E Dillard
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Jacob M Menke
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA; Rhodes College St. Jude Summer Plus Program, Rhodes College, Memphis, TN 38112, USA
| | - Matthew W Frank
- Department of Infectious Disease, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Charles O Rock
- Department of Infectious Disease, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Stacey K Ogden
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
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56
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Abstract
Cilia are microtubule-based organelles extending from a basal body at the surface of eukaryotic cells. Cilia regulate cell and fluid motility, sensation and developmental signaling, and ciliary defects cause human diseases (ciliopathies) affecting the formation and function of many tissues and organs. Over the past decade, various Rab and Rab-like membrane trafficking proteins have been shown to regulate cilia-related processes such as basal body maturation, ciliary axoneme extension, intraflagellar transport and ciliary signaling. In this review, we provide a comprehensive overview of Rab protein ciliary associations, drawing on findings from multiple model systems, including mammalian cell culture, mice, zebrafish, C. elegans, trypanosomes, and green algae. We also discuss several emerging mechanistic themes related to ciliary Rab cascades and functional redundancy.
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Affiliation(s)
- Oliver E Blacque
- a School of Biomolecular and Biomedical Science , University College Dublin , Belfield, Dublin , Ireland
| | - Noemie Scheidel
- a School of Biomolecular and Biomedical Science , University College Dublin , Belfield, Dublin , Ireland
| | - Stefanie Kuhns
- a School of Biomolecular and Biomedical Science , University College Dublin , Belfield, Dublin , Ireland
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57
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Phua SC, Nihongaki Y, Inoue T. Autonomy declared by primary cilia through compartmentalization of membrane phosphoinositides. Curr Opin Cell Biol 2018; 50:72-78. [PMID: 29477020 DOI: 10.1016/j.ceb.2018.01.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Accepted: 01/22/2018] [Indexed: 12/16/2022]
Abstract
The primary cilium is a cell surface projection from plasma membrane which transduces external stimuli to diverse signaling pathways. To function as an independent signaling organelle, the molecular composition of the ciliary membrane has to be distinct from that of the plasma membrane. Here, we review recent findings which have deepened our understanding of the unique yet dynamic phosphoinositide profile found in the primary cilia.
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Affiliation(s)
- Siew Cheng Phua
- Singapore Bioimaging Consortium, Agency for Science, Technology and Research, Singapore 138667, Singapore
| | - Yuta Nihongaki
- Department of Cell Biology and Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Takanari Inoue
- Department of Cell Biology and Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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58
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Bernabé-Rubio M, Alonso MA. Routes and machinery of primary cilium biogenesis. Cell Mol Life Sci 2017; 74:4077-4095. [PMID: 28624967 PMCID: PMC11107551 DOI: 10.1007/s00018-017-2570-5] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Revised: 06/01/2017] [Accepted: 06/13/2017] [Indexed: 02/06/2023]
Abstract
Primary cilia are solitary, microtubule-based protrusions of the cell surface that play fundamental roles as photosensors, mechanosensors and biochemical sensors. Primary cilia dysfunction results in a long list of developmental and degenerative disorders that combine to give rise to a large spectrum of human diseases affecting almost any major body organ. Depending on the cell type, primary ciliogenesis is initiated intracellularly, as in fibroblasts, or at the cell surface, as in renal polarized epithelial cells. In this review, we have focused on the routes of primary ciliogenesis placing particular emphasis on the recently described pathway in renal polarized epithelial cells by which the midbody remnant resulting from a previous cell division event enables the centrosome for initiation of primary cilium assembly. The protein machinery implicated in primary cilium formation in epithelial cells, including the machinery best known for its involvement in establishing cell polarity and polarized membrane trafficking, is also discussed.
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Affiliation(s)
- Miguel Bernabé-Rubio
- Department of Cell Biology and Immunology, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, Nicolás Cabrera 1, Cantoblanco, 28049, Madrid, Spain
| | - Miguel A Alonso
- Department of Cell Biology and Immunology, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, Nicolás Cabrera 1, Cantoblanco, 28049, Madrid, Spain.
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59
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Abstract
Cilia are microtubule-based organelles extending from a basal body at the surface of eukaryotic cells. Cilia regulate cell and fluid motility, sensation and developmental signaling, and ciliary defects cause human diseases (ciliopathies) affecting the formation and function of many tissues and organs. Over the past decade, various Rab and Rab-like membrane trafficking proteins have been shown to regulate cilia-related processes such as basal body maturation, ciliary axoneme extension, intraflagellar transport and ciliary signaling. In this review, we provide a comprehensive overview of Rab protein ciliary associations, drawing on findings from multiple model systems, including mammalian cell culture, mice, zebrafish, C. elegans, trypanosomes, and green algae. We also discuss several emerging mechanistic themes related to ciliary Rab cascades and functional redundancy.
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Affiliation(s)
- Oliver E Blacque
- a School of Biomolecular and Biomedical Science , University College Dublin , Belfield, Dublin , Ireland
| | - Noemie Scheidel
- a School of Biomolecular and Biomedical Science , University College Dublin , Belfield, Dublin , Ireland
| | - Stefanie Kuhns
- a School of Biomolecular and Biomedical Science , University College Dublin , Belfield, Dublin , Ireland
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60
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Mukhopadhyay S, Badgandi HB, Hwang SH, Somatilaka B, Shimada IS, Pal K. Trafficking to the primary cilium membrane. Mol Biol Cell 2017; 28:233-239. [PMID: 28082521 PMCID: PMC5231892 DOI: 10.1091/mbc.e16-07-0505] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 11/14/2016] [Accepted: 11/15/2016] [Indexed: 12/13/2022] Open
Abstract
The primary cilium has been found to be associated with a number of cellular signaling pathways, such as vertebrate hedgehog signaling, and implicated in the pathogenesis of diseases affecting multiple organs, including the neural tube, kidney, and brain. The primary cilium is the site where a subset of the cell's membrane proteins is enriched. However, pathways that target and concentrate membrane proteins in cilia are not well understood. Processes determining the level of proteins in the ciliary membrane include entry into the compartment, removal, and retention by diffusion barriers such as the transition zone. Proteins that are concentrated in the ciliary membrane are also localized to other cellular sites. Thus it is critical to determine the particular role for ciliary compartmentalization in sensory reception and signaling pathways. Here we provide a brief overview of our current understanding of compartmentalization of proteins in the ciliary membrane and the dynamics of trafficking into and out of the cilium. We also discuss major unanswered questions regarding the role that defects in ciliary compartmentalization might play in disease pathogenesis. Understanding the trafficking mechanisms that underlie the role of ciliary compartmentalization in signaling might provide unique approaches for intervention in progressive ciliopathies.
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Affiliation(s)
- Saikat Mukhopadhyay
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX 75390
| | - Hemant B Badgandi
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX 75390
| | - Sun-Hee Hwang
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX 75390
| | | | - Issei S Shimada
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX 75390
| | - Kasturi Pal
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX 75390
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61
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Saito M, Otsu W, Hsu KS, Chuang JZ, Yanagisawa T, Shieh V, Kaitsuka T, Wei FY, Tomizawa K, Sung CH. Tctex-1 controls ciliary resorption by regulating branched actin polymerization and endocytosis. EMBO Rep 2017; 18:1460-1472. [PMID: 28607034 DOI: 10.15252/embr.201744204] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Revised: 05/13/2017] [Accepted: 05/16/2017] [Indexed: 11/09/2022] Open
Abstract
The primary cilium is a plasma membrane-protruding sensory organelle that undergoes regulated assembly and resorption. While the assembly process has been studied extensively, the cellular machinery that governs ciliary resorption is less well understood. Previous studies showed that the ciliary pocket membrane is an actin-rich, endocytosis-active periciliary subdomain. Furthermore, Tctex-1, originally identified as a cytoplasmic dynein light chain, has a dynein-independent role in ciliary resorption upon phosphorylation at Thr94. Here, we show that the remodeling and endocytosis of the ciliary pocket membrane are accelerated during ciliary resorption. This process depends on phospho(T94)Tctex-1, actin, and dynamin. Mechanistically, Tctex-1 physically and functionally interacts with the actin dynamics regulators annexin A2, Arp2/3 complex, and Cdc42. Phospho(T94)Tctex-1 is required for Cdc42 activation before the onset of ciliary resorption. Moreover, inhibiting clathrin-dependent endocytosis or suppressing Rab5GTPase on early endosomes effectively abrogates ciliary resorption. Taken together with the epistasis functional assays, our results support a model in which phospho(T94)Tctex-1-regulated actin polymerization and periciliary endocytosis play an active role in orchestrating the initial phase of ciliary resorption.
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Affiliation(s)
- Masaki Saito
- Department of Molecular Pharmacology, Graduate School of Medicine, Tohoku University, Aoba-ku Sendai, Japan .,Department of Cellular Signaling, Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba-ku Sendai, Japan.,Department of Ophthalmology, Margaret M. Dyson Vision Research Institute, Weill Medical College of Cornell University, New York, NY, USA
| | - Wataru Otsu
- Department of Ophthalmology, Margaret M. Dyson Vision Research Institute, Weill Medical College of Cornell University, New York, NY, USA
| | - Kuo-Shun Hsu
- Department of Ophthalmology, Margaret M. Dyson Vision Research Institute, Weill Medical College of Cornell University, New York, NY, USA
| | - Jen-Zen Chuang
- Department of Ophthalmology, Margaret M. Dyson Vision Research Institute, Weill Medical College of Cornell University, New York, NY, USA
| | - Teruyuki Yanagisawa
- Department of Molecular Pharmacology, Graduate School of Medicine, Tohoku University, Aoba-ku Sendai, Japan
| | - Vincent Shieh
- Department of Ophthalmology, Margaret M. Dyson Vision Research Institute, Weill Medical College of Cornell University, New York, NY, USA
| | - Taku Kaitsuka
- Department of Molecular Physiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
| | - Fan-Yan Wei
- Department of Molecular Physiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
| | - Kazuhito Tomizawa
- Department of Molecular Physiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
| | - Ching-Hwa Sung
- Department of Ophthalmology, Margaret M. Dyson Vision Research Institute, Weill Medical College of Cornell University, New York, NY, USA .,Department of Cell and Developmental Biology, Weill Medical College of Cornell University, New York, NY, USA
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62
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Christensen ST, Morthorst SK, Mogensen JB, Pedersen LB. Primary Cilia and Coordination of Receptor Tyrosine Kinase (RTK) and Transforming Growth Factor β (TGF-β) Signaling. Cold Spring Harb Perspect Biol 2017; 9:cshperspect.a028167. [PMID: 27638178 DOI: 10.1101/cshperspect.a028167] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Since the beginning of the millennium, research in primary cilia has revolutionized our way of understanding how cells integrate and organize diverse signaling pathways during vertebrate development and in tissue homeostasis. Primary cilia are unique sensory organelles that detect changes in their extracellular environment and integrate and transmit signaling information to the cell to regulate various cellular, developmental, and physiological processes. Many different signaling pathways have now been shown to rely on primary cilia to function properly, and mutations that lead to ciliary dysfunction are at the root of a pleiotropic group of diseases and syndromic disorders called ciliopathies. In this review, we present an overview of primary cilia-mediated regulation of receptor tyrosine kinase (RTK) and transforming growth factor β (TGF-β) signaling. Further, we discuss how defects in the coordination of these pathways may be linked to ciliopathies.
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Affiliation(s)
- Søren T Christensen
- Department of Biology, University of Copenhagen, DK-2100 Copenhagen OE, Denmark
| | - Stine K Morthorst
- Department of Biology, University of Copenhagen, DK-2100 Copenhagen OE, Denmark
| | - Johanne B Mogensen
- Department of Biology, University of Copenhagen, DK-2100 Copenhagen OE, Denmark
| | - Lotte B Pedersen
- Department of Biology, University of Copenhagen, DK-2100 Copenhagen OE, Denmark
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63
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Hsu KS, Chuang JZ, Sung CH. The Biology of Ciliary Dynamics. Cold Spring Harb Perspect Biol 2017; 9:cshperspect.a027904. [PMID: 28062565 DOI: 10.1101/cshperspect.a027904] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The cilium is an evolutionally conserved apical membrane protrusion that senses and transduces diverse signals to regulate a wide range of cellular activities. The cilium is dynamic in length, structure, and protein composition. Dysregulation of ciliary dynamics has been linked with ciliopathies and other human diseases. The cilium undergoes cell-cycle-dependent assembly and disassembly, with ciliary resorption linked with G1-S transition and cell-fate choice. In the resting cell, the cilium remains sensitive to environmental cues for remodeling during tissue homeostasis and repair. Recent findings further reveal an interplay between the cilium and extracellular vesicles and identify bioactive cilium-derived vesicles, posing a previously unrecognized role of cilia for sending signals. The photoreceptor outer segment is a notable dynamic cilium. A recently discovered protein transport mechanism in photoreceptors maintains light-regulated homeostasis of ciliary length.
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Affiliation(s)
- Kuo-Shun Hsu
- The Margaret M. Dyson Vision Research Institute, Weill Medical College of Cornell University, New York, New York 10065
| | - Jen-Zen Chuang
- The Margaret M. Dyson Vision Research Institute, Weill Medical College of Cornell University, New York, New York 10065
| | - Ching-Hwa Sung
- Departments of Cell and Developmental Biology, Weill Cornell Medical College, New York, New York 10065
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64
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Urrego D, Sánchez A, Tomczak AP, Pardo LA. The electric fence to cell-cycle progression: Do local changes in membrane potential facilitate disassembly of the primary cilium? Bioessays 2017; 39. [DOI: 10.1002/bies.201600190] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Diana Urrego
- Max-Planck-Institut für experimentelle Medizin; AG Oncophysiology; Göttingen Germany
| | - Araceli Sánchez
- Max-Planck-Institut für experimentelle Medizin; AG Oncophysiology; Göttingen Germany
| | - Adam P. Tomczak
- Max-Planck-Institut für experimentelle Medizin; AG Oncophysiology; Göttingen Germany
| | - Luis A. Pardo
- Max-Planck-Institut für experimentelle Medizin; AG Oncophysiology; Göttingen Germany
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65
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Manna PT, Obado SO, Boehm C, Gadelha C, Sali A, Chait BT, Rout MP, Field MC. Lineage-specific proteins essential for endocytosis in trypanosomes. J Cell Sci 2017; 130:1379-1392. [PMID: 28232524 PMCID: PMC5399782 DOI: 10.1242/jcs.191478] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Accepted: 02/13/2017] [Indexed: 01/05/2023] Open
Abstract
Clathrin-mediated endocytosis (CME) is the most evolutionarily ancient endocytic mechanism known, and in many lineages the sole mechanism for internalisation. Significantly, in mammalian cells CME is responsible for the vast bulk of endocytic flux and has likely undergone multiple adaptations to accommodate specific requirements by individual species. In African trypanosomes, we previously demonstrated that CME is independent of the AP-2 adaptor protein complex, that orthologues to many of the animal and fungal CME protein cohort are absent, and that a novel, trypanosome-restricted protein cohort interacts with clathrin and drives CME. Here, we used a novel cryomilling affinity isolation strategy to preserve transient low-affinity interactions, giving the most comprehensive trypanosome clathrin interactome to date. We identified the trypanosome AP-1 complex, Trypanosoma brucei (Tb)EpsinR, several endosomal SNAREs plus orthologues of SMAP and the AP-2 associated kinase AAK1 as interacting with clathrin. Novel lineage-specific proteins were identified, which we designate TbCAP80 and TbCAP141. Their depletion produced extensive defects in endocytosis and endomembrane system organisation, revealing a novel molecular pathway subtending an early-branching and highly divergent form of CME, which is conserved and likely functionally important across the kinetoplastid parasites. Summary: Endocytosis is a vital process in most cells, and here we identify important proteins required for this process in trypanosomes. Significantly, these are unique and not present in animals, fungi or plants.
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Affiliation(s)
- Paul T Manna
- School of Life Sciences, University of Dundee, Dundee, Scotland DD1 5EH, UK
| | - Samson O Obado
- The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA
| | - Cordula Boehm
- School of Life Sciences, University of Dundee, Dundee, Scotland DD1 5EH, UK
| | - Catarina Gadelha
- School of Life Sciences, University of Nottingham, Nottingham NG2 7UH, UK
| | - Andrej Sali
- California Institute for Quantitative Biosciences, University of California, San Francisco, CA 94158, USA
| | - Brian T Chait
- The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA
| | - Michael P Rout
- The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA
| | - Mark C Field
- School of Life Sciences, University of Dundee, Dundee, Scotland DD1 5EH, UK
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66
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KIF13B establishes a CAV1-enriched microdomain at the ciliary transition zone to promote Sonic hedgehog signalling. Nat Commun 2017; 8:14177. [PMID: 28134340 PMCID: PMC5290278 DOI: 10.1038/ncomms14177] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 12/06/2016] [Indexed: 12/20/2022] Open
Abstract
Ciliary membrane composition is controlled by transition zone (TZ) proteins such as RPGRIP1, RPGRIPL and NPHP4, which are vital for balanced coordination of diverse signalling systems like the Sonic hedgehog (Shh) pathway. Activation of this pathway involves Shh-induced ciliary accumulation of Smoothened (SMO), which is disrupted by disease-causing mutations in TZ components. Here we identify kinesin-3 motor protein KIF13B as a novel member of the RPGRIP1N-C2 domain-containing protein family and show that KIF13B regulates TZ membrane composition and ciliary SMO accumulation. KIF13B is upregulated during ciliogenesis and is recruited to the ciliary base by NPHP4, which binds to two distinct sites in the KIF13B tail region, including an RPGRIP1N-C2 domain. KIF13B and NPHP4 are both essential for establishment of a CAV1 membrane microdomain at the TZ, which in turn is required for Shh-induced ciliary SMO accumulation. Thus KIF13B is a novel regulator of ciliary TZ configuration, membrane composition and Shh signalling.
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Guen VJ, Gamble C, Perez DE, Bourassa S, Zappel H, Gärtner J, Lees JA, Colas P. STAR syndrome-associated CDK10/Cyclin M regulates actin network architecture and ciliogenesis. Cell Cycle 2016; 15:678-88. [PMID: 27104747 DOI: 10.1080/15384101.2016.1147632] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
CDK10/CycM is a protein kinase deficient in STAR (toe Syndactyly, Telecanthus and Anogenital and Renal malformations) syndrome, which results from mutations in the X-linked FAM58A gene encoding Cyclin M. The biological functions of CDK10/CycM and etiology of STAR syndrome are poorly understood. Here, we report that deficiency of CDK10/Cyclin M promotes assembly and elongation of primary cilia. We establish that this reflects a key role for CDK10/Cyclin M in regulation of actin network organization, which is known to govern ciliogenesis. In an unbiased screen, we identified the RhoA-associated kinase PKN2 as a CDK10/CycM phosphorylation substrate. We establish that PKN2 is a bone fide regulator of ciliogenesis, acting in a similar manner to CDK10/CycM. We discovered that CDK10/Cyclin M binds and phosphorylates PKN2 on threonines 121 and 124, within PKN2's core RhoA-binding domain. Furthermore, we demonstrate that deficiencies in CDK10/CycM or PKN2, or expression of a non-phosphorylatable version of PKN2, destabilize both the RhoA protein and the actin network architecture. Importantly, we established that ectopic expression of RhoA is sufficient to override the induction of ciliogenesis resulting from CDK10/CycM knockdown, indicating that RhoA regulation is critical for CDK10/CycM's negative effect on ciliogenesis. Finally, we show that kidney sections from a STAR patient display dilated renal tubules and abnormal, elongated cilia. Altogether, these results reveal CDK10/CycM as a key regulator of actin dynamics and a suppressor of ciliogenesis through phosphorylation of PKN2 and promotion of RhoA signaling. Moreover, they suggest that STAR syndrome is a ciliopathy.
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Affiliation(s)
- Vincent J Guen
- a P2I2 group, Protein Phosphorylation and Human Disease Laboratory, Station Biologique de Roscoff, Centre National de la Recherche Scientifique (CNRS) and Université Pierre et Marie Curie (UPMC) , Roscoff , France.,b David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology (MIT) , Cambridge , MA , USA
| | - Carly Gamble
- a P2I2 group, Protein Phosphorylation and Human Disease Laboratory, Station Biologique de Roscoff, Centre National de la Recherche Scientifique (CNRS) and Université Pierre et Marie Curie (UPMC) , Roscoff , France
| | - Dahlia E Perez
- b David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology (MIT) , Cambridge , MA , USA
| | - Sylvie Bourassa
- c Proteomics Platform, Centre Hospitalier Universitaire de Québec (CHUQ) , Québec , Canada
| | - Hildegard Zappel
- d Universitätsmedizin Göttingen, Department of Child and Adolescent Health, Division of Neuropediatrics , Göttingen , Germany
| | - Jutta Gärtner
- d Universitätsmedizin Göttingen, Department of Child and Adolescent Health, Division of Neuropediatrics , Göttingen , Germany
| | - Jacqueline A Lees
- b David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology (MIT) , Cambridge , MA , USA
| | - Pierre Colas
- a P2I2 group, Protein Phosphorylation and Human Disease Laboratory, Station Biologique de Roscoff, Centre National de la Recherche Scientifique (CNRS) and Université Pierre et Marie Curie (UPMC) , Roscoff , France
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Fadda A, Bärtschi M, Hemphill A, Widmer HR, Zurbriggen A, Perona P, Vidondo B, Oevermann A. Primary Postnatal Dorsal Root Ganglion Culture from Conventionally Slaughtered Calves. PLoS One 2016; 11:e0168228. [PMID: 27936156 PMCID: PMC5148591 DOI: 10.1371/journal.pone.0168228] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Accepted: 11/28/2016] [Indexed: 12/13/2022] Open
Abstract
Neurological disorders in ruminants have an important impact on veterinary health, but very few host-specific in vitro models have been established to study diseases affecting the nervous system. Here we describe a primary neuronal dorsal root ganglia (DRG) culture derived from calves after being conventionally slaughtered for food consumption. The study focuses on the in vitro characterization of bovine DRG cell populations by immunofluorescence analysis. The effects of various growth factors on neuron viability, neurite outgrowth and arborisation were evaluated by morphological analysis. Bovine DRG neurons are able to survive for more than 4 weeks in culture. GF supplementation is not required for neuronal survival and neurite outgrowth. However, exogenously added growth factors promote neurite outgrowth. DRG cultures from regularly slaughtered calves represent a promising and sustainable host specific model for the investigation of pain and neurological diseases in bovines.
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Affiliation(s)
- A. Fadda
- Division of Neurological Sciences, Vetsuisse Faculty, University of Bern, Bern, Switzerland
- Graduate School for Cellular and Biomedical Sciences, Theodor Kocher Institute, University of Bern, Switzerland
| | - M. Bärtschi
- Division of Neurological Sciences, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - A. Hemphill
- Institute for Parasitology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - H. R. Widmer
- Neurocenter and Regenerative Neuroscience Cluster, University Hospital and University of Bern, Bern, Switzerland
| | - A. Zurbriggen
- Division of Neurological Sciences, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - P. Perona
- School of Engineering, The University of Edinburgh, Edinburgh, United Kingdom
| | - B. Vidondo
- Veterinary Public Health Institute (VPHI), Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - A. Oevermann
- Division of Neurological Sciences, Vetsuisse Faculty, University of Bern, Bern, Switzerland
- * E-mail:
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Mazo G, Soplop N, Wang WJ, Uryu K, Tsou MFB. Spatial Control of Primary Ciliogenesis by Subdistal Appendages Alters Sensation-Associated Properties of Cilia. Dev Cell 2016; 39:424-437. [PMID: 27818179 PMCID: PMC5125554 DOI: 10.1016/j.devcel.2016.10.006] [Citation(s) in RCA: 103] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Revised: 09/07/2016] [Accepted: 10/09/2016] [Indexed: 11/22/2022]
Abstract
Vertebrate cells can initiate ciliogenesis from centrioles at the cell center, near the Golgi, forming primary cilia confined or submerged in a deep narrow pit created by membrane invagination. How or why cells maintain submerged cilia is unclear. Here, by characterizing centriole subdistal appendages (sDAP) in cells exclusively growing submerged cilia, we found that a group of sDAP components localize to the centriole proximal end through the cohesion factor C-Nap1 and that sDAP function redundantly with C-Nap1 for submerged cilia maintenance. Loss of sDAP and C-Nap1 has no effect on cilia assembly, but it disrupts stable Golgi-cilia association and allows normally submerged cilia to fully surface, losing the deep membrane invagination. Intriguingly, unlike submerged cilia (stationary), surfaced cilia actively respond to mechanical stimuli with motions and can ectopically recruit Hedgehog signaling components in the absence of agonist. We propose that spatial control of ciliogenesis uncouples or specifies sensory properties of cilia.
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Affiliation(s)
- Gregory Mazo
- Cell Biology Program, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, USA
| | - Nadine Soplop
- Electron Microscopy Resource Center, Rockefeller University, New York, NY 10065, USA
| | - Won-Jing Wang
- Cell Biology Program, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, USA; Institute of Biochemistry and Molecular Biology, College of Life Sciences, National Yang-Ming University, Taipei 112, Taiwan
| | - Kunihiro Uryu
- Electron Microscopy Resource Center, Rockefeller University, New York, NY 10065, USA
| | - Meng Fu Bryan Tsou
- Cell Biology Program, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, USA.
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70
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May-Simera HL, Gumerson JD, Gao C, Campos M, Cologna SM, Beyer T, Boldt K, Kaya KD, Patel N, Kretschmer F, Kelley MW, Petralia RS, Davey MG, Li T. Loss of MACF1 Abolishes Ciliogenesis and Disrupts Apicobasal Polarity Establishment in the Retina. Cell Rep 2016; 17:1399-1413. [PMID: 27783952 PMCID: PMC5123820 DOI: 10.1016/j.celrep.2016.09.089] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Revised: 09/10/2016] [Accepted: 09/27/2016] [Indexed: 12/26/2022] Open
Abstract
Microtubule actin crosslinking factor 1 (MACF1) plays a role in the coordination of microtubules and actin in multiple cellular processes. Here, we show that MACF1 is also critical for ciliogenesis in multiple cell types. Ablation of Macf1 in the developing retina abolishes ciliogenesis, and basal bodies fail to dock to ciliary vesicles or migrate apically. Photoreceptor polarity is randomized, while inner retinal cells laminate correctly, suggesting that photoreceptor maturation is guided by polarity cues provided by cilia. Deletion of MACF1 in adult photoreceptors causes reversal of basal body docking and loss of outer segments, reflecting a continuous requirement for MACF1 function. MACF1 also interacts with the ciliary proteins MKKS and TALPID3. We propose that a disruption of trafficking across microtubles to actin filaments underlies the ciliogenesis defect in cells lacking MACF1 and that MKKS and TALPID3 are involved in the coordination of microtubule and actin interactions.
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Affiliation(s)
| | | | - Chun Gao
- National Eye Institute, Bethesda, MD 20892, USA
| | | | - Stephanie M Cologna
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD 20892, USA
| | - Tina Beyer
- Institute for Ophthalmic Research, University of Tübingen, 72076 Tübingen, Germany
| | - Karsten Boldt
- Institute for Ophthalmic Research, University of Tübingen, 72076 Tübingen, Germany
| | | | - Nisha Patel
- National Eye Institute, Bethesda, MD 20892, USA
| | | | - Matthew W Kelley
- National Institute on Deafness and Other Communication Disorders, Bethesda, MD 20892, USA
| | - Ronald S Petralia
- National Institute on Deafness and Other Communication Disorders, Bethesda, MD 20892, USA
| | - Megan G Davey
- The Roslin Institute, University of Edinburgh, Roslin, Midlothian EH25 9RG, UK
| | - Tiansen Li
- National Eye Institute, Bethesda, MD 20892, USA.
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Pedersen LB, Mogensen JB, Christensen ST. Endocytic Control of Cellular Signaling at the Primary Cilium. Trends Biochem Sci 2016; 41:784-797. [DOI: 10.1016/j.tibs.2016.06.002] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Revised: 06/03/2016] [Accepted: 06/07/2016] [Indexed: 01/20/2023]
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72
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Bernabé-Rubio M, Andrés G, Casares-Arias J, Fernández-Barrera J, Rangel L, Reglero-Real N, Gershlick DC, Fernández JJ, Millán J, Correas I, Miguez DG, Alonso MA. Novel role for the midbody in primary ciliogenesis by polarized epithelial cells. J Cell Biol 2016; 214:259-73. [PMID: 27458130 PMCID: PMC4970324 DOI: 10.1083/jcb.201601020] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Accepted: 06/29/2016] [Indexed: 12/03/2022] Open
Abstract
Polarized epithelial cells assemble a primary cilium by an unknown mechanism. After cytokinesis, the central part of the intercellular bridge, which is referred to as the midbody, is inherited as a remnant by one of the daughter cells. Here, Bernabé-Rubio et al. show that the midbody remnant meets the centrosome at the cell apex, enabling primary ciliogenesis. The primary cilium is a membrane protrusion that is crucial for vertebrate tissue homeostasis and development. Here, we investigated the uncharacterized process of primary ciliogenesis in polarized epithelial cells. We show that after cytokinesis, the midbody is inherited by one of the daughter cells as a remnant that initially locates peripherally at the apical surface of one of the daughter cells. The remnant then moves along the apical surface and, once proximal to the centrosome at the center of the apical surface, enables cilium formation. The physical removal of the remnant greatly impairs ciliogenesis. We developed a probabilistic cell population–based model that reproduces the experimental data. In addition, our model explains, solely in terms of cell area constraints, the various observed transitions of the midbody, the beginning of ciliogenesis, and the accumulation of ciliated cells. Our findings reveal a biological mechanism that links the three microtubule-based organelles—the midbody, the centrosome, and the cilium—in the same cellular process.
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Affiliation(s)
- Miguel Bernabé-Rubio
- Department of Cell Biology and Immunology, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Germán Andrés
- Electron Microscopy Unit, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Javier Casares-Arias
- Department of Cell Biology and Immunology, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Jaime Fernández-Barrera
- Department of Cell Biology and Immunology, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Laura Rangel
- Department of Cell Biology and Immunology, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Natalia Reglero-Real
- Department of Cell Biology and Immunology, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - David C Gershlick
- Cell Biology and Neurobiology Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892
| | - José J Fernández
- Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, 28049 Madrid, Spain
| | - Jaime Millán
- Department of Cell Biology and Immunology, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Isabel Correas
- Department of Cell Biology and Immunology, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - David G Miguez
- Department of Condensed Matter Physics, Instituto de Ciencias de Materiales Nicolás Cabrera and Instituto de Física de la Materia Condensada, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Miguel A Alonso
- Department of Cell Biology and Immunology, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, 28049 Madrid, Spain
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73
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Mourão A, Christensen ST, Lorentzen E. The intraflagellar transport machinery in ciliary signaling. Curr Opin Struct Biol 2016; 41:98-108. [PMID: 27393972 DOI: 10.1016/j.sbi.2016.06.009] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Accepted: 06/07/2016] [Indexed: 01/12/2023]
Abstract
Cilia and flagella on eukaryotic cells are slender microtubule-based projections surrounded by a membrane with a unique lipid and protein composition. It is now appreciated that cilia in addition to their established roles in motility also constitute hubs for cellular signaling by sensing external environmental cues necessary for organ development and maintenance of human health. Pathways reported to rely on the cilium organelle include Hedgehog, TGF-β, Wnt, PDGFRα, integrin and DNA damage repair signaling. An emerging theme in ciliary signaling is the requirement for active transport of signaling components into and out of the cilium proper. Here, we review the current state-of-the-art regarding the importance of intraflagellar transport and BBSome multi-subunit complexes in ciliary signaling.
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Affiliation(s)
- André Mourão
- Department of Structural Cell Biology, Max-Planck-Institute of Biochemistry, Am Klopferspitz 18, D-82152 Martinsried, Germany
| | - Søren T Christensen
- Department of Biology, University of Copenhagen, Universitetsparken 13, DK-2100 Copenhagen, Denmark.
| | - Esben Lorentzen
- Department of Structural Cell Biology, Max-Planck-Institute of Biochemistry, Am Klopferspitz 18, D-82152 Martinsried, Germany.
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74
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Verhey KJ, Yang W. Permeability barriers for generating a unique ciliary protein and lipid composition. Curr Opin Cell Biol 2016; 41:109-16. [PMID: 27232950 DOI: 10.1016/j.ceb.2016.05.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2016] [Revised: 05/04/2016] [Accepted: 05/10/2016] [Indexed: 01/08/2023]
Abstract
Cilia (and flagella) are microtubule-based protrusions that are found in single or multiple copies on the surface of most eukaryotic cells. Defects in cilia formation and/or function have now been correlated with an expanding spectrum of human genetic diseases termed ciliopathies. Recent work indicates that cilia are indeed a bona fide organelle with a unique protein and lipid content that enables specific cellular functions. Despite the physiological and clinical relevance of cilia, our understanding of how a unique protein and lipid composition is generated for this organelle remains poor. Here we review recent work on the mechanisms that determine the protein and lipid content, and thus the functional outputs, of this unique organelle.
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Affiliation(s)
- Kristen J Verhey
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109, USA.
| | - Weidong Yang
- Department of Biology, Temple University, Philadelphia, PA 19122, USA
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75
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Lepanto P, Davison C, Casanova G, Badano JL, Zolessi FR. Characterization of primary cilia during the differentiation of retinal ganglion cells in the zebrafish. Neural Dev 2016; 11:10. [PMID: 27053191 PMCID: PMC4823885 DOI: 10.1186/s13064-016-0064-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 03/29/2016] [Indexed: 01/05/2023] Open
Abstract
Background Retinal ganglion cell (RGC) differentiation in vivo is a highly stereotyped process, likely resulting from the interaction of cell type-specific transcription factors and tissue-derived signaling factors. The primary cilium, as a signaling hub in the cell, may have a role during this process but its presence and localization during RGC generation, and its contribution to the process of cell differentiation, have not been previously assessed in vivo. Methods In this work we analyzed the distribution of primary cilia in vivo using laser scanning confocal microscopy, as well as their main ultrastructural features by transmission electron microscopy, in the early stages of retinal histogenesis in the zebrafish, around the time of RGC generation and initial differentiation. In addition, we knocked-down ift88 and elipsa, two genes with an essential role in cilia generation and maintenance, a treatment that caused a general reduction in organelle size. The effect on retinal development and RGC differentiation was assessed by confocal microscopy of transgenic or immunolabeled embryos. Results Our results show that retinal neuroepithelial cells have an apically-localized primary cilium usually protruding from the apical membrane. We also found a small proportion of sub-apical cilia, before and during the neurogenic period. This organelle was also present in an apical position in neuroblasts during apical process retraction and dendritogenesis, although between these stages cilia appeared highly dynamic regarding both presence and position. Disruption of cilia caused a decrease in the proliferation of retinal progenitors and a reduction of neural retina volume. In addition, retinal histogenesis was globally delayed albeit RGC layer formation was preferentially reduced with respect to the amacrine and photoreceptor cell layers. Conclusions These results indicate that primary cilia exhibit a highly dynamic behavior during early retinal differentiation, and that they are required for the proliferation and survival of retinal progenitors, as well as for neuronal generation, particularly of RGCs. Electronic supplementary material The online version of this article (doi:10.1186/s13064-016-0064-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Paola Lepanto
- Human Molecular Genetics Laboratory, Institut Pasteur de Montevideo, Mataojo 2020, Montevideo, 11400, Uruguay
| | - Camila Davison
- Cell Biology of Neural Development Laboratory, Institut Pasteur de Montevideo, Mataojo 2020, Montevideo, 11400, Uruguay.,Sección Biología Celular, Departamento de Biología Celular y Molecular, Facultad de Ciencias, Universidad de la República, Iguá 4225, Montevideo, 11400, Uruguay
| | - Gabriela Casanova
- Unidad de Microscopía Electrónica, Facultad de Ciencias, Universidad de la República, Iguá 4225, Montevideo, 11400, Uruguay
| | - Jose L Badano
- Human Molecular Genetics Laboratory, Institut Pasteur de Montevideo, Mataojo 2020, Montevideo, 11400, Uruguay.
| | - Flavio R Zolessi
- Cell Biology of Neural Development Laboratory, Institut Pasteur de Montevideo, Mataojo 2020, Montevideo, 11400, Uruguay. .,Sección Biología Celular, Departamento de Biología Celular y Molecular, Facultad de Ciencias, Universidad de la República, Iguá 4225, Montevideo, 11400, Uruguay.
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76
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Pal K, Hwang SH, Somatilaka B, Badgandi H, Jackson PK, DeFea K, Mukhopadhyay S. Smoothened determines β-arrestin-mediated removal of the G protein-coupled receptor Gpr161 from the primary cilium. J Cell Biol 2016; 212:861-75. [PMID: 27002170 PMCID: PMC4810300 DOI: 10.1083/jcb.201506132] [Citation(s) in RCA: 100] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 02/11/2016] [Indexed: 02/08/2023] Open
Abstract
Dynamic changes in membrane protein composition of the primary cilium are central to development and homeostasis, but we know little about mechanisms regulating membrane protein flux. Stimulation of the sonic hedgehog (Shh) pathway in vertebrates results in accumulation and activation of the effector Smoothened within cilia and concomitant disappearance of a negative regulator, the orphan G protein-coupled receptor (GPCR), Gpr161. Here, we describe a two-step process determining removal of Gpr161 from cilia. The first step involves β-arrestin recruitment by the signaling competent receptor, which is facilitated by the GPCR kinase Grk2. An essential factor here is the ciliary trafficking and activation of Smoothened, which by increasing Gpr161-β-arrestin binding promotes Gpr161 removal, both during resting conditions and upon Shh pathway activation. The second step involves clathrin-mediated endocytosis, which functions outside of the ciliary compartment in coordinating Gpr161 removal. Mechanisms determining dynamic compartmentalization of Gpr161 in cilia define a new paradigm for down-regulation of GPCRs during developmental signaling from a specialized subcellular compartment.
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Affiliation(s)
- Kasturi Pal
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Sun-Hee Hwang
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Bandarigoda Somatilaka
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Hemant Badgandi
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Peter K Jackson
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA 94305
| | - Kathryn DeFea
- Division of Biomedical Sciences, University of California, Riverside, Riverside, CA 92521
| | - Saikat Mukhopadhyay
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
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Vaughan S, Gull K. Basal body structure and cell cycle-dependent biogenesis in Trypanosoma brucei. Cilia 2016; 5:5. [PMID: 26862392 PMCID: PMC4746817 DOI: 10.1186/s13630-016-0023-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Accepted: 01/19/2016] [Indexed: 11/10/2022] Open
Abstract
Basal bodies are microtubule-based organelles that assemble cilia and flagella, which are critical for motility and sensory functions in all major eukaryotic lineages. The core structure of the basal body is highly conserved, but there is variability in biogenesis and additional functions that are organism and cell type specific. Work carried out in the protozoan parasite Trypanosoma brucei has arguably produced one of the most detailed dissections of basal body structure and biogenesis within the context of the flagellar pocket and associated organelles. In this review, we provide a detailed overview of the basic basal body structure in T. brucei along with the accessory structures and show how basal body movements during the basal body duplication cycle orchestrate cell and organelle morphogenesis. With this in-depth three-dimensional knowledge, identification of many basal body genes coupled with excellent genetic tools makes it an attractive model organism to study basal body biogenesis and maintenance.
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Affiliation(s)
- Sue Vaughan
- Department of Biological and Medical Sciences, Faculty of Health and Life Science, Oxford Brookes University, Oxford, OX3 0BP UK
| | - Keith Gull
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford, OX1 3RE UK
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78
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Pampliega O, Cuervo AM. Autophagy and primary cilia: dual interplay. Curr Opin Cell Biol 2016; 39:1-7. [PMID: 26826446 DOI: 10.1016/j.ceb.2016.01.008] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Revised: 01/08/2016] [Accepted: 01/13/2016] [Indexed: 12/11/2022]
Abstract
Primary cilia are microtubule-based organelles for sensing of the extracellular milieu and transducing this information into the cell through a variety of molecular signaling pathways. Functioning of the primary cilium has been recently connected to autophagy, a pathway for degradation of cellular components in lysosomes. Autophagy regulates the length of the cilia by removing proteins required for ciliogenesis, a phenomenon that is molecularly different if performed by basal autophagy or when autophagy is induced in response to various stressors. Here we review the current knowledge about the dual interaction between autophagy and ciliogenesis, and discuss the potential role that deregulated ciliary autophagy could have in pathologies with alterations in autophagy and ciliogenesis.
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Affiliation(s)
- Olatz Pampliega
- Université de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, 33000 Bordeaux, France; CNRS, Institut des Maladies Neurodégénératives, UMR 5293, 33000 Bordeaux, France.
| | - Ana Maria Cuervo
- Department of Developmental and Molecular Biology, Institute for Aging Studies, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA
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79
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Ghossoub R, Lindbæk L, Molla-Herman A, Schmitt A, Christensen ST, Benmerah A. Morphological and Functional Characterization of the Ciliary Pocket by Electron and Fluorescence Microscopy. Methods Mol Biol 2016; 1454:35-51. [PMID: 27514914 DOI: 10.1007/978-1-4939-3789-9_3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
In many vertebrate cell types, the proximal part of the primary cilium is positioned within an invagination of the plasma membrane known as the ciliary pocket. Recent evidence points to the conclusion that the ciliary pocket comprises a unique site for exocytosis and endocytosis of ciliary proteins, which regulates the spatiotemporal trafficking of receptors into and out of the cilium to control its sensory function. In this chapter, we provide methods based on electron microscopy, 3D reconstruction of fluorescence images as well as live cell imaging suitable for investigating processes associated with endocytosis at the ciliary pocket.
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Affiliation(s)
- Rania Ghossoub
- Centre de Recherche en Cancérologie de Marseille (CRCM), Inserm, U1068-CNRS UMR7258, Institut Paoli-Calmettes, Aix-Marseille Université, 13009, Marseille, France
| | - Louise Lindbæk
- Department of Biology, University of Copenhagen, Universitetsparken 13, DK-2100, Copenhagen, OE, Denmark
| | - Anahi Molla-Herman
- Department of Genetics and Developmental Biology, Institut Curie, Paris, France
- CNRS, UMR, Paris, France
| | - Alain Schmitt
- INSERM, U1016, Institut Cochin, 75014, Paris, France
- CNRS, UMR8104, 75014, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, 75006, Paris, France
| | - Søren Tvorup Christensen
- Department of Biology, University of Copenhagen, Universitetsparken 13, DK-2100, Copenhagen, OE, Denmark.
| | - Alexandre Benmerah
- INSERM, UMR-1163, Laboratory of Inherited Kidney Diseases, 75015, Paris, France.
- Université Paris Descartes-Sorbonne Paris Cité, Imagine Institut, 75015, Paris, France.
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80
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Recruitment of β-Arrestin into Neuronal Cilia Modulates Somatostatin Receptor Subtype 3 Ciliary Localization. Mol Cell Biol 2015; 36:223-35. [PMID: 26503786 DOI: 10.1128/mcb.00765-15] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 10/20/2015] [Indexed: 01/09/2023] Open
Abstract
Primary cilia are essential sensory and signaling organelles present on nearly every mammalian cell type. Defects in primary cilia underlie a class of human diseases collectively termed ciliopathies. Primary cilia are restricted subcellular compartments, and specialized mechanisms coordinate the localization of proteins to cilia. Moreover, trafficking of proteins into and out of cilia is required for proper ciliary function, and this process is disrupted in ciliopathies. The somatostatin receptor subtype 3 (Sstr3) is selectively targeted to primary cilia on neurons in the mammalian brain and is implicated in learning and memory. Here, we show that Sstr3 localization to cilia is dynamic and decreases in response to somatostatin treatment. We further show that somatostatin treatment stimulates β-arrestin recruitment into Sstr3-positive cilia and this recruitment can be blocked by mutations in Sstr3 that impact agonist binding or phosphorylation. Importantly, somatostatin treatment fails to decrease Sstr3 ciliary localization in neurons lacking β-arrestin 2. Together, our results implicate β-arrestin in the modulation of Sstr3 ciliary localization and further suggest a role for β-arrestin in the mediation of Sstr3 ciliary signaling.
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82
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Schou KB, Pedersen LB, Christensen ST. Ins and outs of GPCR signaling in primary cilia. EMBO Rep 2015; 16:1099-113. [PMID: 26297609 DOI: 10.15252/embr.201540530] [Citation(s) in RCA: 145] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Accepted: 07/01/2015] [Indexed: 12/17/2022] Open
Abstract
Primary cilia are specialized microtubule-based signaling organelles that convey extracellular signals into a cellular response in most vertebrate cell types. The physiological significance of primary cilia is underscored by the fact that defects in assembly or function of these organelles lead to a range of severe diseases and developmental disorders. In most cell types of the human body, signaling by primary cilia involves different G protein-coupled receptors (GPCRs), which transmit specific signals to the cell through G proteins to regulate diverse cellular and physiological events. Here, we provide an overview of GPCR signaling in primary cilia, with main focus on the rhodopsin-like (class A) and the smoothened/frizzled (class F) GPCRs. We describe how such receptors dynamically traffic into and out of the ciliary compartment and how they interact with other classes of ciliary GPCRs, such as class B receptors, to control ciliary function and various physiological and behavioral processes. Finally, we discuss future avenues for developing GPCR-targeted drug strategies for the treatment of ciliopathies.
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83
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Novas R, Cardenas-Rodriguez M, Irigoín F, Badano JL. Bardet-Biedl syndrome: Is it only cilia dysfunction? FEBS Lett 2015; 589:3479-91. [PMID: 26231314 DOI: 10.1016/j.febslet.2015.07.031] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 07/14/2015] [Accepted: 07/15/2015] [Indexed: 01/12/2023]
Abstract
Bardet-Biedl syndrome (BBS) is a genetically heterogeneous, pleiotropic disorder, characterized by both congenital and late onset defects. From the analysis of the mutational burden in patients to the functional characterization of the BBS proteins, this syndrome has become a model for both understanding oligogenic patterns of inheritance and the biology of a particular cellular organelle: the primary cilium. Here we briefly review the genetics of BBS to then focus on the function of the BBS proteins, not only in the context of the cilium but also highlighting potential extra-ciliary roles that could be relevant to the etiology of the disorder. Finally, we provide an overview of how the study of this rare syndrome has contributed to the understanding of cilia biology and how this knowledge has informed on the cellular basis of different clinical manifestations that characterize BBS and the ciliopathies.
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Affiliation(s)
- Rossina Novas
- Human Molecular Genetics Laboratory, Institut Pasteur de Montevideo, Mataojo 2020, Montevideo CP11400, Uruguay
| | | | - Florencia Irigoín
- Human Molecular Genetics Laboratory, Institut Pasteur de Montevideo, Mataojo 2020, Montevideo CP11400, Uruguay; Departamento de Histología y Embriología, Facultad de Medicina, Universidad de la República, Montevideo, Gral. Flores 2125, Montevideo CP11800, Uruguay
| | - Jose L Badano
- Human Molecular Genetics Laboratory, Institut Pasteur de Montevideo, Mataojo 2020, Montevideo CP11400, Uruguay.
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84
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Rachel RA, Yamamoto EA, Dewanjee MK, May-Simera HL, Sergeev YV, Hackett AN, Pohida K, Munasinghe J, Gotoh N, Wickstead B, Fariss RN, Dong L, Li T, Swaroop A. CEP290 alleles in mice disrupt tissue-specific cilia biogenesis and recapitulate features of syndromic ciliopathies. Hum Mol Genet 2015; 24:3775-91. [PMID: 25859007 DOI: 10.1093/hmg/ddv123] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2014] [Accepted: 04/07/2015] [Indexed: 12/22/2022] Open
Abstract
Distinct mutations in the centrosomal-cilia protein CEP290 lead to diverse clinical findings in syndromic ciliopathies. We show that CEP290 localizes to the transition zone in ciliated cells, precisely to the region of Y-linkers between central microtubules and plasma membrane. To create models of CEP290-associated ciliopathy syndromes, we generated Cep290(ko/ko) and Cep290(gt/gt) mice that produce no or a truncated CEP290 protein, respectively. Cep290(ko/ko) mice exhibit early vision loss and die from hydrocephalus. Retinal photoreceptors in Cep290(ko/ko) mice lack connecting cilia, and ciliated ventricular ependyma fails to mature. The minority of Cep290(ko/ko) mice that escape hydrocephalus demonstrate progressive kidney pathology. Cep290(gt/gt) mice die at mid-gestation, and the occasional Cep290(gt/gt) mouse that survives shows hydrocephalus and severely cystic kidneys. Partial loss of CEP290-interacting ciliopathy protein MKKS mitigates lethality and renal pathology in Cep290(gt/gt) mice. Our studies demonstrate domain-specific functions of CEP290 and provide novel therapeutic paradigms for ciliopathies.
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Affiliation(s)
| | | | | | | | | | | | | | - Jeeva Munasinghe
- National Institute of Neurological Disease and Stroke, National Institutes of Health, Bethesda, MD 20892, USA and
| | | | - Bill Wickstead
- School of Life Sciences, University of Nottingham, Nottingham, UK
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85
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Stinchcombe JC, Griffiths GM. Communication, the centrosome and the immunological synapse. Philos Trans R Soc Lond B Biol Sci 2015; 369:rstb.2013.0463. [PMID: 25047617 PMCID: PMC4113107 DOI: 10.1098/rstb.2013.0463] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Recent findings on the behaviour of the centrosome at the immunological synapse suggest a critical role for centrosome polarization in controlling the communication between immune cells required to generate an effective immune response. The features observed at the immunological synapse show parallels to centrosome (basal body) polarization seen in cilia and flagella, and the cellular communication that is now known to occur at all of these sites.
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Affiliation(s)
- Jane C Stinchcombe
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 OXY, UK
| | - Gillian M Griffiths
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 OXY, UK
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86
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Yuan X, Serra RA, Yang S. Function and regulation of primary cilia and intraflagellar transport proteins in the skeleton. Ann N Y Acad Sci 2015; 1335:78-99. [PMID: 24961486 PMCID: PMC4334369 DOI: 10.1111/nyas.12463] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Primary cilia are microtubule-based organelles that project from the cell surface to enable transduction of various developmental signaling pathways. The process of intraflagellar transport (IFT) is crucial for the building and maintenance of primary cilia. Ciliary dysfunction has been found in a range of disorders called ciliopathies, some of which display severe skeletal dysplasias. In recent years, interest has grown in uncovering the function of primary cilia/IFT proteins in bone development, mechanotransduction, and cellular regulation. We summarize recent advances in understanding the function of cilia and IFT proteins in the regulation of cell differentiation in osteoblasts, osteocytes, chondrocytes, and mesenchymal stem cells (MSCs). We also discuss the mechanosensory function of cilia and IFT proteins in bone cells, cilia orientation, and other functions of cilia in chondrocytes.
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Affiliation(s)
- Xue Yuan
- Department of Oral Biology, School of Dental Medicine, University at Buffalo, The State University of New York, Buffalo, NY
| | - Rosa A. Serra
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Shuying Yang
- Department of Oral Biology, School of Dental Medicine, University at Buffalo, The State University of New York, Buffalo, NY
- Developmental Genomics Group, New York State Center of Excellence in Bioinformatics and Life Sciences, University at Buffalo, The State University of New York, Buffalo, NY
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87
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Benmerah A. La poche ciliaire : fruit des liaisons du centrosome avec le trafic vésiculaire. Med Sci (Paris) 2014; 30:962-7. [DOI: 10.1051/medsci/20143011009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
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88
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Orhon I, Dupont N, Pampliega O, Cuervo AM, Codogno P. Autophagy and regulation of cilia function and assembly. Cell Death Differ 2014; 22:389-97. [PMID: 25361082 DOI: 10.1038/cdd.2014.171] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Revised: 09/05/2014] [Accepted: 09/10/2014] [Indexed: 12/21/2022] Open
Abstract
Motile and primary cilia (PC) are microtubule-based structures located at the cell surface of many cell types. Cilia govern cellular functions ranging from motility to integration of mechanical and chemical signaling from the environment. Recent studies highlight the interplay between cilia and autophagy, a conserved cellular process responsible for intracellular degradation. Signaling from the PC recruits the autophagic machinery to trigger autophagosome formation. Conversely, autophagy regulates ciliogenesis by controlling the levels of ciliary proteins. The cross talk between autophagy and ciliated structures is a novel aspect of cell biology with major implications in development, physiology and human pathologies related to defects in cilium function.
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Affiliation(s)
- I Orhon
- 1] INSERM U1151-CNRS UMR 8253, Paris, France [2] Institut Necker Enfants-Malades (INEM), Paris, France [3] Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - N Dupont
- 1] INSERM U1151-CNRS UMR 8253, Paris, France [2] Institut Necker Enfants-Malades (INEM), Paris, France [3] Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - O Pampliega
- 1] Department of Development and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY, USA [2] Institute for Aging Studies, Albert Einstein College of Medicine, Bronx, NY, USA
| | - A M Cuervo
- 1] Department of Development and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY, USA [2] Institute for Aging Studies, Albert Einstein College of Medicine, Bronx, NY, USA
| | - P Codogno
- 1] INSERM U1151-CNRS UMR 8253, Paris, France [2] Institut Necker Enfants-Malades (INEM), Paris, France [3] Université Paris Descartes, Sorbonne Paris Cité, Paris, France
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89
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Antunes G, Sebastião AM, Simoes de Souza FM. Mechanisms of regulation of olfactory transduction and adaptation in the olfactory cilium. PLoS One 2014; 9:e105531. [PMID: 25144232 PMCID: PMC4140790 DOI: 10.1371/journal.pone.0105531] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Accepted: 07/23/2014] [Indexed: 12/11/2022] Open
Abstract
Olfactory adaptation is a fundamental process for the functioning of the olfactory system, but the underlying mechanisms regulating its occurrence in intact olfactory sensory neurons (OSNs) are not fully understood. In this work, we have combined stochastic computational modeling and a systematic pharmacological study of different signaling pathways to investigate their impact during short-term adaptation (STA). We used odorant stimulation and electroolfactogram (EOG) recordings of the olfactory epithelium treated with pharmacological blockers to study the molecular mechanisms regulating the occurrence of adaptation in OSNs. EOG responses to paired-pulses of odorants showed that inhibition of phosphodiesterases (PDEs) and phosphatases enhanced the levels of STA in the olfactory epithelium, and this effect was mimicked by blocking vesicle exocytosis and reduced by blocking cyclic adenosine monophosphate (cAMP)-dependent protein kinase (PKA) and vesicle endocytosis. These results suggest that G-coupled receptors (GPCRs) cycling is involved with the occurrence of STA. To gain insights on the dynamical aspects of this process, we developed a stochastic computational model. The model consists of the olfactory transduction currents mediated by the cyclic nucleotide gated (CNG) channels and calcium ion (Ca2+)-activated chloride (CAC) channels, and the dynamics of their respective ligands, cAMP and Ca2+, and it simulates the EOG results obtained under different experimental conditions through changes in the amplitude and duration of cAMP and Ca2+ response, two second messengers implicated with STA occurrence. The model reproduced the experimental data for each pharmacological treatment and provided a mechanistic explanation for the action of GPCR cycling in the levels of second messengers modulating the levels of STA. All together, these experimental and theoretical results indicate the existence of a mechanism of regulation of STA by signaling pathways that control GPCR cycling and tune the levels of second messengers in OSNs, and not only by CNG channel desensitization as previously thought.
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Affiliation(s)
- Gabriela Antunes
- Neurosciences Unit, Institute of Molecular Medicine, University of Lisbon, Lisbon, Portugal; Laboratory of Neural Systems, Psychobiology Sector, Department of Psychology, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Ana Maria Sebastião
- Institute of Pharmacology and Neurosciences, Faculty of Medicine, University of Lisbon, Lisbon, Portugal; Neurosciences Unit, Institute of Molecular Medicine, University of Lisbon, Lisbon, Portugal
| | - Fabio Marques Simoes de Souza
- Neurosciences Unit, Institute of Molecular Medicine, University of Lisbon, Lisbon, Portugal; Center for Mathematics, Computation and Cognition, Federal University of ABC, São Bernardo do Campo, Brazil
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90
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Madhivanan K, Aguilar RC. Ciliopathies: the trafficking connection. Traffic 2014; 15:1031-56. [PMID: 25040720 DOI: 10.1111/tra.12195] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Revised: 06/28/2014] [Accepted: 07/08/2014] [Indexed: 12/15/2022]
Abstract
The primary cilium (PC) is a very dynamic hair-like membrane structure that assembles/disassembles in a cell-cycle-dependent manner and is present in almost every cell type. Despite being continuous with the plasma membrane, a diffusion barrier located at the ciliary base confers the PC properties of a separate organelle with very specific characteristics and membrane composition. Therefore, vesicle trafficking is the major process by which components are acquired for cilium formation and maintenance. In fact, a system of specific sorting signals controls the right of cargo admission into the cilia. Disruption to the ciliary structure or its function leads to multiorgan diseases known as ciliopathies. These illnesses arise from a spectrum of mutations in any of the more than 50 loci linked to these conditions. Therefore, it is not surprising that symptom variability (specific manifestations and severity) among and within ciliopathies appears to be an emerging characteristic. Nevertheless, one can speculate that mutations occurring in genes whose products contribute to the overall vesicle trafficking to the PC (i.e. affecting cilia assembly) will lead to more severe symptoms, whereas those involved in the transport of specific cargoes will result in milder phenotypes. In this review, we summarize the trafficking mechanisms to the cilia and also provide a description of the trafficking defects observed in some ciliopathies which can be correlated to the severity of the pathology.
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91
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Satir BH, Wyroba E, Liu L, Lethan M, Satir P, Christensen ST. Evolutionary implications of localization of the signaling scaffold protein parafusin to both cilia and the nucleus. Cell Biol Int 2014; 39:136-45. [PMID: 25044011 DOI: 10.1002/cbin.10337] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Accepted: 07/11/2014] [Indexed: 11/08/2022]
Abstract
Parafusin (PFUS), a 63 kDa protein first discovered in the eukaryote Paramecium and known for its role in apicomplexan exocytosis, provides a model for the common origin of cellular systems employing scaffold proteins for targeting and signaling. PFUS is closely related to eubacterial rather than archeal phosphoglucomutases (PGM) - as we proved by comparison of their 88 sequences - but has no PGM activity. Immunofluorescence microscopy analysis with a PFUS-specific peptide antibody showed presence of this protein around the base region of primary cilia in a variety of mammalian cell types, including mouse embryonic (MEFs) and human foreskin fibroblasts (hFFs), human carcinoma stem cells (NT-2 cells), and human retinal pigment epithelial (RPE) cells. Further, PFUS localized to the nucleus of fibroblasts, and prominently to nucleoli of MEFs. Localization studies were confirmed by Western blot analysis, showing that the PFUS antibody specifically recognizes a single protein of ca. 63 kDa in both cytoplasmic and nuclear fractions. Finally, immunofluorescence microscopy analysis showed that PFUS localized to nuclei and cilia in Paramecium. These results support the suggestion that PFUS plays a role in signaling between nucleus and cilia, and that the cilium and the nucleus both evolved around the time of eukaryotic emergence. We hypothesize that near the beginnings of eukaryotic cell evolution, scaffold proteins such as PFUS arose as peripheral membrane protein identifiers for cytoplasmic membrane trafficking and were employed similarly during the subsequent evolution of exocytic, nuclear transport, and ciliogenic mechanisms.
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Affiliation(s)
- Birgit Hegner Satir
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Jack and Pearl Resnick Campus, 1300 Morris Park Avenue, Forchheimer Building, Bronx, NY, 10461, USA
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92
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Abstract
Trypanosoma brucei is a pathogenic unicellular eukaryote that infects humans and other mammals in sub-Saharan Africa. A central feature of trypanosome biology is the single flagellum of the parasite, which is an essential and multifunctional organelle that facilitates cell propulsion, controls cell morphogenesis and directs cytokinesis. Moreover, the flagellar membrane is a specialized subdomain of the cell surface that mediates attachment to host tissues and harbours multiple virulence factors. In this Review, we discuss the structure, assembly and function of the trypanosome flagellum, including canonical roles in cell motility as well as novel and emerging roles in cell morphogenesis and host-parasite interactions.
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Affiliation(s)
- Gerasimos Langousis
- Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles, CA90095
| | - Kent L. Hill
- Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles, CA90095
- Molecular Biology Institute, University of California, Los Angeles, CA90095
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93
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Ke YN, Yang WX. Primary cilium: an elaborate structure that blocks cell division? Gene 2014; 547:175-85. [PMID: 24971504 DOI: 10.1016/j.gene.2014.06.050] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Revised: 05/07/2014] [Accepted: 06/23/2014] [Indexed: 11/25/2022]
Abstract
A primary cilium is a microtubule-based membranous protrusion found in almost all cell types. A primary cilium has a "9+0" axoneme that distinguishes this ancient organelle from the canonical motile "9+2" cilium. A primary cilium is the sensory center of the cell that regulates cell proliferation and embryonic development. The primary ciliary pocket is a specialized endocytic membrane domain in the basal region. The basal body of a primary cilium exists as a form of the centriole during interphase of the cell cycle. Although conventional thinking suggests that the cell cycle regulates centrosomal changes, recent studies suggest the opposite, that is, centrosomal changes regulate the cell cycle. In this regard, centrosomal kinase Aurora kinase A (AurA), Polo-like kinase 1 (Plk1), and NIMA related Kinase (Nek or Nrk) propel cell cycle progression by promoting primary cilia disassembly which indicates a non-mitotic function. However, the persistence of primary cilia during spermatocyte division challenges the dominate idea of the incompatibility of primary cilia and cell division. In this review, we demonstrate the detailed structure of primary cilia and discuss the relationship between primary cilia disassembly and cell cycle progression on the background of various mitotic kinases.
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Affiliation(s)
- Yi-Ni Ke
- The Sperm Laboratory, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Wan-Xi Yang
- The Sperm Laboratory, College of Life Sciences, Zhejiang University, Hangzhou 310058, China.
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94
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Abstract
The primary cilium compartmentalizes a tiny fraction of the cell surface and volume, yet many proteins are highly enriched in this area and so efficient mechanisms are necessary to concentrate them in the ciliary compartment. Here we review mechanisms that are thought to deliver protein cargo to the base of cilia and are likely to interact with ciliary gating mechanisms. Given the immense variety of ciliary cytosolic and transmembrane proteins, it is almost certain that multiple, albeit frequently interconnected, pathways mediate this process. It is also clear that none of these pathways is fully understood at the present time. Mechanisms that are discussed below facilitate ciliary localization of structural and signaling molecules, which include receptors, G-proteins, ion channels, and enzymes. These mechanisms form a basis for every aspect of cilia function in early embryonic patterning, organ morphogenesis, sensory perception and elsewhere.
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Affiliation(s)
- Jarema Malicki
- MRC Centre for Developmental and Biomedical Genetics; Department of Biomedical Science; The University of Sheffield; Sheffield, UK
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95
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Mathieu PS, Bodle JC, Loboa EG. Primary cilium mechanotransduction of tensile strain in 3D culture: Finite element analyses of strain amplification caused by tensile strain applied to a primary cilium embedded in a collagen matrix. J Biomech 2014; 47:2211-7. [PMID: 24831236 DOI: 10.1016/j.jbiomech.2014.04.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Revised: 03/28/2014] [Accepted: 04/05/2014] [Indexed: 01/22/2023]
Abstract
Human adipose-derived stem cells (hASC) exhibit multilineage differentiation potential with lineage specification that is dictated by both the chemical and mechanical stimuli to which they are exposed. We have previously shown that 10% cyclic tensile strain increases hASC osteogenesis and cell-mediated calcium accretion. We have also recently shown that primary cilia are present on hASC and that chemically-induced lineage specification of hASC concurrently results in length and conformation changes of the primary cilia. Further, we have observed cilia length changes in hASC cultured within a collagen I gel in response to 10% cyclic tensile strain. We therefore hypothesize that primary cilia may play a key mechanotransduction role for hASC exposed to tensile strain. The goal of this study was to use finite element analysis (FEA) to determine strains occurring within the ciliary membrane in response to 10% tensile strain applied parallel, or perpendicular, to cilia orientation. To elucidate the mechanical environment experienced by the cilium, several lengths were modeled and evaluated based on cilia lengths measured on hASC grown under varied culture conditions. Principal tensile strains in both hASC and ciliary membranes were calculated using FEA, and the magnitude and location of maximum principal tensile strain determined. We found that maximum principal tensile strain was concentrated at the base of the cilium. In the linear elastic model, applying strain perpendicular to the cilium resulted in maximum strains within the ciliary membrane from 150% to 200%, while applying strain parallel to the cilium resulted in much higher strains, approximately 400%. In the hyperelastic model, applying strain perpendicular to the cilium resulted in maximum strains within the ciliary membrane around 30%, while applying strain parallel to the cilium resulted in much higher strains ranging from 50% to 70%. Interestingly, FEA results indicated that primary cilium length was not directly related to ciliary membrane strain. Rather, it appears that cilium orientation may be more important than cilium length in determining sensitivity of hASC to tensile strain. This is the first study to model the effects of tensile strain on the primary cilium and provides newfound insight into the potential role of the primary cilium as a mechanosensor, particularly in tensile strain and potentially a multitude of other mechanical stimuli beyond fluid shear.
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Affiliation(s)
- Pattie S Mathieu
- Joint Department of Biomedical Engineering at North Carolina State University and University of North Carolina-Chapel Hill, Engineering Building III (EB3) 4208B, Box 7115, NCSU Campus, Raleigh, NC 27695, USA
| | - Josephine C Bodle
- Joint Department of Biomedical Engineering at North Carolina State University and University of North Carolina-Chapel Hill, Engineering Building III (EB3) 4208B, Box 7115, NCSU Campus, Raleigh, NC 27695, USA
| | - Elizabeth G Loboa
- Joint Department of Biomedical Engineering at North Carolina State University and University of North Carolina-Chapel Hill, Engineering Building III (EB3) 4208B, Box 7115, NCSU Campus, Raleigh, NC 27695, USA; Department of Materials Science & Engineering, North Carolina State University, USA.
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96
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Ruppersburg CC, Hartzell HC. The Ca2+-activated Cl- channel ANO1/TMEM16A regulates primary ciliogenesis. Mol Biol Cell 2014; 25:1793-807. [PMID: 24694595 PMCID: PMC4038505 DOI: 10.1091/mbc.e13-10-0599] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The Ca2+-activated Cl− channel ANO1/TMEM16A is located in the primary cilium, and blocking it pharmacologically or knocking it down with shRNA interferes with ciliogenesis. Before ciliogenesis, the channel is organized into a torus-shaped structure (the “nimbus”) enriched in proteins required for ciliogenesis. Many cells possess a single, nonmotile, primary cilium highly enriched in receptors and sensory transduction machinery that plays crucial roles in cellular morphogenesis. Although sensory transduction requires ion channels, relatively little is known about ion channels in the primary cilium (with the exception of TRPP2). Here we show that the Ca2+-activated Cl− channel anoctamin-1 (ANO1/TMEM16A) is located in the primary cilium and that blocking its channel function pharmacologically or knocking it down with short hairpin RNA interferes with ciliogenesis. Before ciliogenesis, the channel becomes organized into a torus-shaped structure (“the nimbus”) enriched in proteins required for ciliogenesis, including the small GTPases Cdc42 and Arl13b and the exocyst complex component Sec6. The nimbus excludes F-actin and coincides with a ring of acetylated microtubules. The nimbus appears to form before, or independent of, apical docking of the mother centriole. Our data support a model in which the nimbus provides a scaffold for staging of ciliary components for assembly very early in ciliogenesis and chloride transport by ANO1/TMEM16A is required for the genesis or maintenance of primary cilia.
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Affiliation(s)
| | - H Criss Hartzell
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322
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97
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Koefoed K, Veland IR, Pedersen LB, Larsen LA, Christensen ST. Cilia and coordination of signaling networks during heart development. Organogenesis 2013; 10:108-25. [PMID: 24345806 DOI: 10.4161/org.27483] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Primary cilia are unique sensory organelles that coordinate a wide variety of different signaling pathways to control cellular processes during development and in tissue homeostasis. Defects in function or assembly of these antenna-like structures are therefore associated with a broad range of developmental disorders and diseases called ciliopathies. Recent studies have indicated a major role of different populations of cilia, including nodal and cardiac primary cilia, in coordinating heart development, and defects in these cilia are associated with congenital heart disease. Here, we present an overview of the role of nodal and cardiac primary cilia in heart development.
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Affiliation(s)
- Karen Koefoed
- Department of Biology; University of Copenhagen; Copenhagen, Denmark; Wilhelm Johannsen Centre for Functional Genome Research; Department of Cellular and Molecular Medicine; University of Copenhagen; Copenhagen, Denmark
| | - Iben Rønn Veland
- Department of Biology; University of Copenhagen; Copenhagen, Denmark
| | | | - Lars Allan Larsen
- Wilhelm Johannsen Centre for Functional Genome Research; Department of Cellular and Molecular Medicine; University of Copenhagen; Copenhagen, Denmark
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98
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Millier MJ, Singh K, Poole CA. Characterization of Primary Cilia Distribution and Morphology During Lactation, Stasis, and Involution in the Bovine Mammary Gland. Anat Rec (Hoboken) 2013; 296:1943-53. [DOI: 10.1002/ar.22819] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2013] [Revised: 08/16/2013] [Accepted: 09/06/2013] [Indexed: 11/06/2022]
Affiliation(s)
- Melanie J. Millier
- Department of Medicine; Dunedin School of Medicine; University of Otago; Dunedin New Zealand
| | - Kuljeet Singh
- AgResearch Ltd.; Ruakura Research Centre; Hamilton New Zealand
| | - C. Anthony Poole
- Department of Medicine; Dunedin School of Medicine; University of Otago; Dunedin New Zealand
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99
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Gottardo M, Callaini G, Riparbelli MG. The cilium-like region of the Drosophila spermatocyte: an emerging flagellum? J Cell Sci 2013; 126:5441-52. [PMID: 24105264 DOI: 10.1242/jcs.136523] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Primary cilia and flagella are distinct structures with different functions in eukaryotic cells. Despite the fact that they share similar basic organization and architecture, a direct developmental continuity among them has not been reported until now. The primary cilium is a dynamic structure that typically assembles and disassembles during mitotic cell cycles, whereas the sperm axoneme is nucleated by the centriole inherited by the differentiating spermatid at the end of meiosis. Fruit flies display a remarkable exception to this general rule. Drosophila spermatocytes have an unusual axoneme-based structure reminiscent of primary cilia (the cilium-like region, or CLR). This structure persists through the meiotic divisions when it is internalized with the centriole to organize the centrosome and is finally inherited by young spermatids. Examination of elongating spermatids by transmission electron microscopy (EM) and cold regrowth experiments suggests that the motile axoneme derives directly from the elongation and remodelling of the immotile CLR. Both the CLR and elongating spermatid flagella have incomplete C-tubules that form longitudinal sheets associated with the B-tubule wall, unlike axonemes of other organisms in which C-tubules stop growing at the transition between the basal body and the axonemal doublets. Moreover, both the CLR and spermatid flagella lack a structured transition zone, a characteristic feature of ciliated cells. Uncoordinated (unc) mutants that lack C-remnants have short centrioles, suggesting that the C-sheets play a role in the elongation of the centriole after it docks to the cell membrane. The structural similarities between CLR and sperm axoneme suggest that the CLR can be considered as the basal region of the future axoneme and could represent the start point for its elongation.
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Affiliation(s)
- Marco Gottardo
- Department of Life Sciences, University of Siena, Via A. Moro 4, 53100 Siena, Italy
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100
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Abstract
Odontoblasts are dentin-secreting cells that survive for the whole life of a healthy tooth. Once teeth are completely erupted, odontoblasts transform into a mature stage that allows for their functional conservation for decades, while maintaining the capacity for secondary and reactionary dentin secretion. Odontoblasts are also critically involved in the transmission of sensory stimuli from the dentin-pulp complex and in the cellular defense against pathogens. Their longevity is sustained by an elaborate autophagic-lysosomal system that ensures organelle and protein renewal. However, progressive dysfunction of this system, in part caused by lipofuscin accumulation, reduces the fitness of odontoblasts and eventually impairs their dentin maintenance capacity. Here we review the functional activities assumed by mature odontoblasts throughout life. Understanding the biological basis of age-related changes in human odontoblasts is crucial to improving tooth preservation in the elderly.
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Affiliation(s)
- E. Couve
- Departamento de Biología, Laboratorio de Microscopía Electrónica
- Facultad de Ciencias, Universidad de Valparaíso, Avda. Gran Bretaña 1111, Playa Ancha, Valparaíso, Chile
| | - R. Osorio
- Departamento de Biología, Laboratorio de Microscopía Electrónica
- Facultad de Ciencias, Universidad de Valparaíso, Avda. Gran Bretaña 1111, Playa Ancha, Valparaíso, Chile
| | - O. Schmachtenberg
- Centro Interdisciplinario de Neurociencia de Valparaíso (CINV)
- Facultad de Ciencias, Universidad de Valparaíso, Avda. Gran Bretaña 1111, Playa Ancha, Valparaíso, Chile
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