1
|
Macarelli V, Harding EC, Gershlick DC, Merkle FT. A Short Sequence Targets Transmembrane Proteins to Primary Cilia. Cells 2024; 13:1156. [PMID: 38995007 PMCID: PMC11240719 DOI: 10.3390/cells13131156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2024] [Revised: 06/26/2024] [Accepted: 07/02/2024] [Indexed: 07/13/2024] Open
Abstract
Primary cilia are finger-like sensory organelles that extend from the bodies of most cell types and have a distinct lipid and protein composition from the plasma membrane. This partitioning is maintained by a diffusion barrier that restricts the entry of non-ciliary proteins, and allows the selective entry of proteins harboring a ciliary targeting sequence (CTS). However, CTSs are not stereotyped and previously reported sequences are insufficient to drive efficient ciliary localisation across diverse cell types. Here, we describe a short peptide sequence that efficiently targets transmembrane proteins to primary cilia in all tested cell types, including human neurons. We generate human-induced pluripotent stem cell (hiPSC) lines stably expressing a transmembrane construct bearing an extracellular HaloTag and intracellular fluorescent protein, which enables the bright, specific labeling of primary cilia in neurons and other cell types to facilitate studies of cilia in health and disease. We demonstrate the utility of this resource by developing an image analysis pipeline for the automated measurement of primary cilia to detect changes in their length associated with altered signaling or disease state.
Collapse
Affiliation(s)
- Viviana Macarelli
- Institute of Metabolic Science, University of Cambridge, Cambridge CB2 0QQ, UK
- Cambridge Stem Cell Institute, University of Cambridge, Cambridge CB2 0AW, UK
| | - Edward C Harding
- Institute of Metabolic Science, University of Cambridge, Cambridge CB2 0QQ, UK
| | - David C Gershlick
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, UK
| | - Florian T Merkle
- Institute of Metabolic Science, University of Cambridge, Cambridge CB2 0QQ, UK
- Cambridge Stem Cell Institute, University of Cambridge, Cambridge CB2 0AW, UK
| |
Collapse
|
2
|
Adamson SE, Hughes JW. Paracrine Signaling by Pancreatic Islet Cilia. CURRENT OPINION IN ENDOCRINE AND METABOLIC RESEARCH 2024; 35:100505. [PMID: 38524256 PMCID: PMC10956557 DOI: 10.1016/j.coemr.2024.100505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/26/2024]
Abstract
The primary cilium is a sensory and signaling organelle present on most pancreatic islet endocrine cells, where it receives and interprets a wide range of intra-islet chemical cues including hormones, peptides, and neurotransmitters. The ciliary membrane possesses a molecular composition distinct from the plasma membrane, with enrichment of signaling mediators including G protein-coupled receptors (GPCRs), tyrosine kinase family receptors, membrane transporters and others. When activated, these membrane proteins interact with ion channels and adenylyl cyclases to trigger local Ca2+ and cAMP activity and transmit signals to the cell body. Here we review evidence supporting the emerging model in which primary cilia on pancreatic islet cells play a central role in the intra-islet communication network and discuss how changes in cilia-mediated paracrine function in islet cells might lead to diabetes.
Collapse
Affiliation(s)
- Samantha E Adamson
- Division of Endocrinology, Metabolism & Lipid Research, Washington University School of Medicine, St. Louis, MO, USA
| | - Jing W Hughes
- Division of Endocrinology, Metabolism & Lipid Research, Washington University School of Medicine, St. Louis, MO, USA
| |
Collapse
|
3
|
Adamson SE, Li ZA, Hughes JW. Beta cell primary cilia mediate somatostatin responsiveness via SSTR3. Islets 2023; 15:2252855. [PMID: 37660302 PMCID: PMC10478741 DOI: 10.1080/19382014.2023.2252855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 08/23/2023] [Accepted: 08/24/2023] [Indexed: 09/05/2023] Open
Abstract
Somatostatin is a paracrine modulator of insulin secretion and beta cell function with pleotropic effects on glucose homeostasis. The mechanism of somatostatin-mediated communication between delta and beta cells is not well-understood, which we address in this study via the ciliary somatostatin receptor 3 (SSTR3). Primary cilia are membrane organelles that act as signaling hubs in islets by virtue of their subcellular location and enrichment in signaling proteins such as G-protein coupled receptors (GPCRs). We show that SSTR3, a ciliary GPCR, mediates somatostatin suppression of insulin secretion in mouse islets. Quantitative analysis of calcium flux using a mouse model of genetically encoded beta cell-specific GCaMP6f calcium reporter shows that somatostatin signaling alters beta cell calcium flux after physiologic glucose stimulation, an effect that depends on endogenous SSTR3 expression and the presence of intact primary cilia on beta cells. Comparative in vitro studies using SSTR isoform antagonists demonstrate a role for SSTR3 in mediating somatostatin regulation of insulin secretion in mouse islets. Our findings support a model in which ciliary SSTR3 mediates a distinct pathway of delta-to-beta cell regulatory crosstalk and may serve as a target for paracrine modulation.
Collapse
Affiliation(s)
- Samantha E. Adamson
- Department of Medicine, Division of Endocrinology, Metabolism & Lipid Research, Washington University School of Medicine, St. Louis, USA
| | - Zipeng A. Li
- Department of Medicine, Division of Endocrinology, Metabolism & Lipid Research, Washington University School of Medicine, St. Louis, USA
| | - Jing W. Hughes
- Department of Medicine, Division of Endocrinology, Metabolism & Lipid Research, Washington University School of Medicine, St. Louis, USA
| |
Collapse
|
4
|
Gopalakrishnan J, Feistel K, Friedrich BM, Grapin‐Botton A, Jurisch‐Yaksi N, Mass E, Mick DU, Müller R, May‐Simera H, Schermer B, Schmidts M, Walentek P, Wachten D. Emerging principles of primary cilia dynamics in controlling tissue organization and function. EMBO J 2023; 42:e113891. [PMID: 37743763 PMCID: PMC10620770 DOI: 10.15252/embj.2023113891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 08/07/2023] [Accepted: 09/08/2023] [Indexed: 09/26/2023] Open
Abstract
Primary cilia project from the surface of most vertebrate cells and are key in sensing extracellular signals and locally transducing this information into a cellular response. Recent findings show that primary cilia are not merely static organelles with a distinct lipid and protein composition. Instead, the function of primary cilia relies on the dynamic composition of molecules within the cilium, the context-dependent sensing and processing of extracellular stimuli, and cycles of assembly and disassembly in a cell- and tissue-specific manner. Thereby, primary cilia dynamically integrate different cellular inputs and control cell fate and function during tissue development. Here, we review the recently emerging concept of primary cilia dynamics in tissue development, organization, remodeling, and function.
Collapse
Affiliation(s)
- Jay Gopalakrishnan
- Institute for Human Genetics, Heinrich‐Heine‐UniversitätUniversitätsklinikum DüsseldorfDüsseldorfGermany
| | - Kerstin Feistel
- Department of Zoology, Institute of BiologyUniversity of HohenheimStuttgartGermany
| | | | - Anne Grapin‐Botton
- Cluster of Excellence Physics of Life, TU DresdenDresdenGermany
- Max Planck Institute of Molecular Cell Biology and GeneticsDresdenGermany
- Paul Langerhans Institute Dresden of the Helmholtz Center Munich at The University Hospital Carl Gustav Carus and Faculty of Medicine of the TU DresdenDresdenGermany
| | - Nathalie Jurisch‐Yaksi
- Department of Clinical and Molecular MedicineNorwegian University of Science and TechnologyTrondheimNorway
| | - Elvira Mass
- Life and Medical Sciences Institute, Developmental Biology of the Immune SystemUniversity of BonnBonnGermany
| | - David U Mick
- Center for Molecular Signaling (PZMS), Center of Human and Molecular Biology (ZHMB)Saarland School of MedicineHomburgGermany
| | - Roman‐Ulrich Müller
- Department II of Internal Medicine and Center for Molecular Medicine Cologne, Faculty of Medicine and University Hospital CologneUniversity of CologneCologneGermany
- Cologne Excellence Cluster on Cellular Stress Responses in Aging‐Associated Diseases (CECAD), Faculty of Medicine and University Hospital CologneUniversity of CologneCologneGermany
| | - Helen May‐Simera
- Institute of Molecular PhysiologyJohannes Gutenberg‐UniversityMainzGermany
| | - Bernhard Schermer
- Department II of Internal Medicine and Center for Molecular Medicine Cologne, Faculty of Medicine and University Hospital CologneUniversity of CologneCologneGermany
- Cologne Excellence Cluster on Cellular Stress Responses in Aging‐Associated Diseases (CECAD), Faculty of Medicine and University Hospital CologneUniversity of CologneCologneGermany
| | - Miriam Schmidts
- Pediatric Genetics Division, Center for Pediatrics and Adolescent MedicineUniversity Hospital FreiburgFreiburgGermany
- CIBSS‐Centre for Integrative Biological Signalling StudiesUniversity of FreiburgFreiburgGermany
| | - Peter Walentek
- CIBSS‐Centre for Integrative Biological Signalling StudiesUniversity of FreiburgFreiburgGermany
- Renal Division, Internal Medicine IV, Medical CenterUniversity of FreiburgFreiburgGermany
| | - Dagmar Wachten
- Institute of Innate Immunity, Biophysical Imaging, Medical FacultyUniversity of BonnBonnGermany
| |
Collapse
|
5
|
Lee EY, Hughes JW. Rediscovering Primary Cilia in Pancreatic Islets. Diabetes Metab J 2023; 47:454-469. [PMID: 37105527 PMCID: PMC10404530 DOI: 10.4093/dmj.2022.0442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Accepted: 03/15/2023] [Indexed: 04/29/2023] Open
Abstract
Primary cilia are microtubule-based sensory and signaling organelles on the surfaces of most eukaryotic cells. Despite their early description by microscopy studies, islet cilia had not been examined in the functional context until recent decades. In pancreatic islets as in other tissues, primary cilia facilitate crucial developmental and signaling pathways in response to extracellular stimuli. Many human developmental and genetic disorders are associated with ciliary dysfunction, some manifesting as obesity and diabetes. Understanding the basis for metabolic diseases in human ciliopathies has been aided by close examination of cilia action in pancreatic islets at cellular and molecular levels. In this article, we review the evidence for ciliary expression on islet cells, known roles of cilia in pancreas development and islet hormone secretion, and summarize metabolic manifestations of human ciliopathy syndromes. We discuss emerging data on primary cilia regulation of islet cell signaling and the structural basis of cilia-mediated cell crosstalk, and offer our interpretation on the role of cilia in glucose homeostasis and human diseases.
Collapse
Affiliation(s)
- Eun Young Lee
- Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Jing W. Hughes
- Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| |
Collapse
|
6
|
Lu Q, Westlake CJ. Multi-color live-cell fluorescence imaging of primary ciliary membrane assembly and dynamics. Methods Cell Biol 2023; 176:235-250. [PMID: 37164540 PMCID: PMC11302370 DOI: 10.1016/bs.mcb.2023.02.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
Abstract
The ciliary membrane is continuous with the plasma membrane but has distinct lipid and protein composition, which is key to defining the function of the primary cilium. Ciliary membranes dynamically assemble and disassemble in association with the cell cycle and directly transmit signals and molecules through budding membranes. Various imaging approaches have greatly advanced the understanding of the ciliary membrane function. In particular, fluorescence live-cell imaging has revealed important insights into the dynamics of ciliary membrane assembly by monitoring the changes of fluorescent-tagged ciliary proteins. Protein dynamics can be tracked simultaneously using multi-color live cell imaging by coupling ciliary-associated factors with different colored fluorescent tags. Ciliary membrane and membrane associated-proteins such as Smoothened, 5-HTr6, SSTR3, Rab8a, and Arl13b have been used to track ciliary membranes and centriole proteins like Centrin1/2, CEP164, and CEP83 are often used to mark the ciliary basal body. Here, we describe a method for studying ciliogenesis membrane dynamics using spinning disk confocal live-cell imaging.
Collapse
Affiliation(s)
- Quanlong Lu
- Laboratory of Cell and Developmental Signaling, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD, United States.
| | - Christopher J Westlake
- Laboratory of Cell and Developmental Signaling, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD, United States.
| |
Collapse
|
7
|
Chabosseau P, Yong F, Delgadillo-Silva LF, Lee EY, Melhem R, Li S, Gandhi N, Wastin J, Noriega LL, Leclerc I, Ali Y, Hughes JW, Sladek R, Martinez-Sanchez A, Rutter GA. Molecular phenotyping of single pancreatic islet leader beta cells by "Flash-Seq". Life Sci 2023; 316:121436. [PMID: 36706832 DOI: 10.1016/j.lfs.2023.121436] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 01/11/2023] [Accepted: 01/20/2023] [Indexed: 01/26/2023]
Abstract
AIMS Spatially-organized increases in cytosolic Ca2+ within pancreatic beta cells in the pancreatic islet underlie the stimulation of insulin secretion by high glucose. Recent data have revealed the existence of subpopulations of beta cells including "leaders" which initiate Ca2+ waves. Whether leader cells possess unique molecular features, or localisation, is unknown. MAIN METHODS High speed confocal Ca2+ imaging was used to identify leader cells and connectivity analysis, running under MATLAB and Python, to identify highly connected "hub" cells. To explore transcriptomic differences between beta cell sub-groups, individual leaders or followers were labelled by photo-activation of the cryptic fluorescent protein PA-mCherry and subjected to single cell RNA sequencing ("Flash-Seq"). KEY FINDINGS Distinct Ca2+ wave types were identified in individual islets, with leader cells present in 73 % (28 of 38 islets imaged). Scale-free, power law-adherent behaviour was also observed in 29 % of islets, though "hub" cells in these islets did not overlap with leaders. Transcripts differentially expressed (295; padj < 0.05) between leader and follower cells included genes involved in cilium biogenesis and transcriptional regulation. Providing some support for these findings, ADCY6 immunoreactivity tended to be higher in leader than follower cells, whereas cilia number and length tended to be lower in the former. Finally, leader cells were located significantly closer to delta, but not alpha, cells in Euclidian space than were follower cells. SIGNIFICANCE The existence of both a discrete transcriptome and unique localisation implies a role for these features in defining the specialized function of leaders. These data also raise the possibility that localised signalling between delta and leader cells contributes to the initiation and propagation of islet Ca2+ waves.
Collapse
Affiliation(s)
- Pauline Chabosseau
- Centre de Recherche du CHUM, Faculté de Médicine, Université de Montréal, Montréal, QC, Canada
| | - Fiona Yong
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Faculty of Medicine, Imperial College London, London W12 0NN, United Kingdom; Lee Kong Chian Imperial Medical School, Nanyang Technological University, Singapore
| | - Luis F Delgadillo-Silva
- Centre de Recherche du CHUM, Faculté de Médicine, Université de Montréal, Montréal, QC, Canada
| | - Eun Young Lee
- Department of Medicine, Washington University School of Medicine, Saint Louis, MO, United States; Division of Endocrinology and Metabolism, Department of Internal Medicine, Seoul St. Mary's Hospital, The Catholic University of Korea, Seoul, South Korea
| | - Rana Melhem
- Centre de Recherche du CHUM, Faculté de Médicine, Université de Montréal, Montréal, QC, Canada
| | - Shiying Li
- Centre de Recherche du CHUM, Faculté de Médicine, Université de Montréal, Montréal, QC, Canada
| | - Nidhi Gandhi
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Faculty of Medicine, Imperial College London, London W12 0NN, United Kingdom
| | - Jules Wastin
- Centre de Recherche du CHUM, Faculté de Médicine, Université de Montréal, Montréal, QC, Canada
| | - Livia Lopez Noriega
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Faculty of Medicine, Imperial College London, London W12 0NN, United Kingdom
| | - Isabelle Leclerc
- Centre de Recherche du CHUM, Faculté de Médicine, Université de Montréal, Montréal, QC, Canada
| | - Yusuf Ali
- Lee Kong Chian Imperial Medical School, Nanyang Technological University, Singapore
| | - Jing W Hughes
- Department of Medicine, Washington University School of Medicine, Saint Louis, MO, United States
| | - Robert Sladek
- Departments of Medicine and Human Genetics, McGill University and Genome Quebec Innovation Centre, Montreal, QC, Canada
| | - Aida Martinez-Sanchez
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Faculty of Medicine, Imperial College London, London W12 0NN, United Kingdom
| | - Guy A Rutter
- Centre de Recherche du CHUM, Faculté de Médicine, Université de Montréal, Montréal, QC, Canada; Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Faculty of Medicine, Imperial College London, London W12 0NN, United Kingdom; Lee Kong Chian Imperial Medical School, Nanyang Technological University, Singapore.
| |
Collapse
|
8
|
Djenoune L, Mahamdeh M, Truong TV, Nguyen CT, Fraser SE, Brueckner M, Howard J, Yuan S. Cilia function as calcium-mediated mechanosensors that instruct left-right asymmetry. Science 2023; 379:71-78. [PMID: 36603098 PMCID: PMC9939240 DOI: 10.1126/science.abq7317] [Citation(s) in RCA: 45] [Impact Index Per Article: 45.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 12/09/2022] [Indexed: 01/06/2023]
Abstract
The breaking of bilateral symmetry in most vertebrates is critically dependent upon the motile cilia of the embryonic left-right organizer (LRO), which generate a directional fluid flow; however, it remains unclear how this flow is sensed. Here, we demonstrated that immotile LRO cilia are mechanosensors for shear force using a methodological pipeline that combines optical tweezers, light sheet microscopy, and deep learning to permit in vivo analyses in zebrafish. Mechanical manipulation of immotile LRO cilia activated intraciliary calcium transients that required the cation channel Polycystin-2. Furthermore, mechanical force applied to LRO cilia was sufficient to rescue and reverse cardiac situs in zebrafish that lack motile cilia. Thus, LRO cilia are mechanosensitive cellular levers that convert biomechanical forces into calcium signals to instruct left-right asymmetry.
Collapse
Affiliation(s)
- Lydia Djenoune
- Cardiovascular Research Center, Cardiology Division, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA
| | - Mohammed Mahamdeh
- Cardiovascular Research Center, Cardiology Division, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA
| | - Thai V. Truong
- Translational Imaging Center, University of Southern California, Los Angeles, CA 90089, USA
| | - Christopher T. Nguyen
- Cardiovascular Research Center, Cardiology Division, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA
- Cardiovascular Innovation Research Center, Heart, Vascular, and Thoracic Institute, Cleveland Clinic, Cleveland, OH 44195, USA
- Division of Health Science Technology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Scott E. Fraser
- Translational Imaging Center, University of Southern California, Los Angeles, CA 90089, USA
| | - Martina Brueckner
- Departments of Pediatrics and Genetics, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Jonathon Howard
- Department of Molecular Biochemistry and Biophysics, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Shiaulou Yuan
- Cardiovascular Research Center, Cardiology Division, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA
| |
Collapse
|
9
|
Zekaj N, Ryan SD, Resnick A. Fluid-structure interaction modelling of neighboring tubes with primary cilium analysis. MATHEMATICAL BIOSCIENCES AND ENGINEERING : MBE 2023; 20:3677-3699. [PMID: 36899599 DOI: 10.3934/mbe.2023172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
We have developed a numerical model of two osculating cylindrical elastic renal tubules to investigate the impact of neighboring tubules on the stress applied to a primary cilium. We hypothesize that the stress at the base of the primary cilium will depend on the mechanical coupling of the tubules due to local constrained motion of the tubule wall. The objective of this work was to determine the in-plane stresses of a primary cilium attached to the inner wall of one renal tubule subject to the applied pulsatile flow, with a neighboring renal tube filled with stagnant fluid in close proximity to the primary tubule. We used the commercial software COMSOLⓇ to model the fluid-structure interaction of the applied flow and tubule wall, and we applied a boundary load to the face of the primary cilium during this simulation to produces a stress at its base. We confirm our hypothesis by observing that on average the in-plane stresses are greater at the base of the cilium when there is a neighboring renal tube versus if there is no neighboring tube at all. In combination with the hypothesized function of a cilium as a biological fluid flow sensor, these results indicate that flow signaling may also depend on how the tubule wall is constrained by neighboring tubules. Our results may be limited in their interpretation due to the simplified nature of our model geometry, and further improvements to the model may potentially lead to the design of future experiments.
Collapse
Affiliation(s)
- Nerion Zekaj
- Department of Mathematics, University of North Carolina at Chapel Hill, Chapel Hill 27599, USA
| | - Shawn D Ryan
- Department of Mathematics and Statistics, Cleveland State University, Cleveland OH 44115, USA
| | - Andrew Resnick
- Department of Physics, Cleveland State University, Cleveland OH 44115, USA
- Center for Gene Regulation in Health and Disease, Cleveland State University, Cleveland OH 44115, USA
| |
Collapse
|
10
|
Melena I, Hughes JW. Islet cilia and glucose homeostasis. Front Cell Dev Biol 2022; 10:1082193. [PMID: 36531945 PMCID: PMC9751591 DOI: 10.3389/fcell.2022.1082193] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Accepted: 11/22/2022] [Indexed: 09/05/2023] Open
Abstract
Diabetes is a growing pandemic affecting over ten percent of the U.S. population. Individuals with all types of diabetes exhibit glucose dysregulation due to altered function and coordination of pancreatic islets. Within the critical intercellular space in pancreatic islets, the primary cilium emerges as an important physical structure mediating cell-cell crosstalk and signal transduction. Many events leading to hormone secretion, including GPCR and second-messenger signaling, are spatiotemporally regulated at the level of the cilium. In this review, we summarize current knowledge of cilia action in islet hormone regulation and glucose homeostasis, focusing on newly implicated ciliary pathways that regulate insulin exocytosis and intercellular communication. We present evidence of key signaling proteins on islet cilia and discuss ways in which cilia might functionally connect islet endocrine cells with the non-endocrine compartments. These discussions aim to stimulate conversations regarding the extent of cilia-controlled glucose homeostasis in health and in metabolic diseases.
Collapse
Affiliation(s)
| | - Jing W. Hughes
- Division of Endocrinology, Metabolism and Lipid Research, Department of Medicine, Washington University School of Medicine, Saint Louis, MO, United States
| |
Collapse
|
11
|
Li ZA, Cho JH, Woodhams LG, Hughes JW. Fluorescence imaging of beta cell primary cilia. Front Endocrinol (Lausanne) 2022; 13:1004136. [PMID: 36213262 PMCID: PMC9540379 DOI: 10.3389/fendo.2022.1004136] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 09/01/2022] [Indexed: 11/25/2022] Open
Abstract
Primary cilia are slender cell-surface organelles that project into the intercellular space. In pancreatic beta cells, primary cilia coordinate a variety of cell responses including GPCR signaling, calcium influx, and insulin secretion, along with likely many underappreciated roles in islet development and differentiation. To study cilia function in islet biology, direct visualization of primary cilia by microscopic methods is often a necessary first step. Ciliary abundance, distribution, and morphology are heterogeneous among islet cells and are best visualized by fluorescence microscopy, the tools for which are readily accessible to most researchers. Here we present a collection of fluorescence imaging methods that we have adopted and optimized for the observation of primary cilia in mouse and human islets. These include conventional confocal microscopy using fixed islets and pancreas sections, live-cell imaging with cilia-targeted biosensors and probes, cilia motion recordings, and quantitative analysis of primary cilia waveform in the ex vivo environment. We discuss practical considerations and limitations of our approaches as well as new tools on the horizon to facilitate the observation of primary cilia in pancreatic islets.
Collapse
Affiliation(s)
- Zipeng A. Li
- Department of Medicine, Washington University School of Medicine, Saint Louis, MO, United States
| | - Jung Hoon Cho
- Department of Medicine, Washington University School of Medicine, Saint Louis, MO, United States
| | - Louis G. Woodhams
- Department of Mechanical Engineering and Materials Science, Washington University McKelvey School of Engineering, Saint Louis, MO, United States
| | - Jing W. Hughes
- Department of Medicine, Washington University School of Medicine, Saint Louis, MO, United States
| |
Collapse
|
12
|
Cho JH, Li ZA, Zhu L, Muegge BD, Roseman HF, Lee EY, Utterback T, Woodhams LG, Bayly PV, Hughes JW. Islet primary cilia motility controls insulin secretion. SCIENCE ADVANCES 2022; 8:eabq8486. [PMID: 36149960 PMCID: PMC9506710 DOI: 10.1126/sciadv.abq8486] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 07/13/2022] [Indexed: 06/16/2023]
Abstract
Primary cilia are specialized cell-surface organelles that mediate sensory perception and, in contrast to motile cilia and flagella, are thought to lack motility function. Here, we show that primary cilia in human and mouse pancreatic islets exhibit movement that is required for glucose-dependent insulin secretion. Islet primary cilia contain motor proteins conserved from those found in classic motile cilia, and their three-dimensional motion is dynein-driven and dependent on adenosine 5'-triphosphate and glucose metabolism. Inhibition of cilia motion blocks beta cell calcium influx and insulin secretion. Human beta cells have enriched ciliary gene expression, and motile cilia genes are altered in type 2 diabetes. Our findings redefine primary cilia as dynamic structures having both sensory and motile function and establish that pancreatic islet cilia movement plays a regulatory role in insulin secretion.
Collapse
Affiliation(s)
- Jung Hoon Cho
- Department of Medicine, Washington University School of Medicine, 660 South Euclid Ave, St. Louis, MO, USA
| | - Zipeng A. Li
- Department of Medicine, Washington University School of Medicine, 660 South Euclid Ave, St. Louis, MO, USA
| | - Lifei Zhu
- Department of Medicine, Washington University School of Medicine, 660 South Euclid Ave, St. Louis, MO, USA
| | - Brian D. Muegge
- Department of Medicine, Washington University School of Medicine, 660 South Euclid Ave, St. Louis, MO, USA
- Department of Medicine, VA Medical Center, 915 North Grand Blvd, St. Louis, MO, USA
| | - Henry F. Roseman
- Department of Medicine, Washington University School of Medicine, 660 South Euclid Ave, St. Louis, MO, USA
| | - Eun Young Lee
- Department of Medicine, Washington University School of Medicine, 660 South Euclid Ave, St. Louis, MO, USA
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Seoul St. Mary’s Hospital, The Catholic University of Korea, Seoul, South Korea
| | - Toby Utterback
- Department of Mechanical Engineering and Materials Science, Washington University McKelvey School of Engineering, 1 Brookings Drive, St. Louis, MO, USA
| | - Louis G. Woodhams
- Department of Mechanical Engineering and Materials Science, Washington University McKelvey School of Engineering, 1 Brookings Drive, St. Louis, MO, USA
| | - Philip V. Bayly
- Department of Mechanical Engineering and Materials Science, Washington University McKelvey School of Engineering, 1 Brookings Drive, St. Louis, MO, USA
| | - Jing W. Hughes
- Department of Medicine, Washington University School of Medicine, 660 South Euclid Ave, St. Louis, MO, USA
| |
Collapse
|
13
|
Yang C, Harafuji N, O'Connor AK, Kesterson RA, Watts JA, Majmundar AJ, Braun DA, Lek M, Laricchia KM, Fathy HM, Mane S, Shril S, Hildebrandt F, Guay-Woodford LM. Cystin genetic variants cause autosomal recessive polycystic kidney disease associated with altered Myc expression. Sci Rep 2021; 11:18274. [PMID: 34521872 PMCID: PMC8440558 DOI: 10.1038/s41598-021-97046-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 07/22/2021] [Indexed: 11/08/2022] Open
Abstract
Mutation of the Cys1 gene underlies the renal cystic disease in the Cys1cpk/cpk (cpk) mouse that phenocopies human autosomal recessive polycystic kidney disease (ARPKD). Cystin, the protein product of Cys1, is expressed in the primary apical cilia of renal ductal epithelial cells. In previous studies, we showed that cystin regulates Myc expression via interaction with the tumor suppressor, necdin. Here, we demonstrate rescue of the cpk renal phenotype by kidney-specific expression of a cystin-GFP fusion protein encoded by a transgene integrated into the Rosa26 locus. In addition, we show that expression of the cystin-GFP fusion protein in collecting duct cells down-regulates expression of Myc in cpk kidneys. Finally, we report the first human patient with an ARPKD phenotype due to homozygosity for a deleterious splicing variant in CYS1. These findings suggest that mutations in Cys1/CYS1 cause an ARPKD phenotype in mouse and human, respectively, and that the renal cystic phenotype in the mouse is driven by overexpression of the Myc proto-oncogene.
Collapse
Affiliation(s)
- Chaozhe Yang
- Center for Translational Research, Children's National Research Institute, 111 Michigan Ave NW, Washington, DC, 20010, USA
| | - Naoe Harafuji
- Center for Translational Research, Children's National Research Institute, 111 Michigan Ave NW, Washington, DC, 20010, USA
| | - Amber K O'Connor
- Center for Translational Research, Children's National Research Institute, 111 Michigan Ave NW, Washington, DC, 20010, USA
| | - Robert A Kesterson
- Department of Genetics, University of Alabama at Birmingham, Birmingham, AL, 35294, USA
| | - Jacob A Watts
- Center for Translational Research, Children's National Research Institute, 111 Michigan Ave NW, Washington, DC, 20010, USA
- Department of Genetics, University of Alabama at Birmingham, Birmingham, AL, 35294, USA
| | - Amar J Majmundar
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Daniela A Braun
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Monkol Lek
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Kristen M Laricchia
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Hanan M Fathy
- Alexandria Faculty of Medicine, University of Alexandria, Alexandria, Egypt
| | - Shrikant Mane
- Department of Genetics, Yale University School of Medicine, New Haven, CT, USA
- Yale Center for Mendelian Genomics, Yale University School of Medicine, New Haven, CT, USA
| | - Shirlee Shril
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Friedhelm Hildebrandt
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Lisa M Guay-Woodford
- Center for Translational Research, Children's National Research Institute, 111 Michigan Ave NW, Washington, DC, 20010, USA.
- Department of Genetics, University of Alabama at Birmingham, Birmingham, AL, 35294, USA.
| |
Collapse
|
14
|
Ning K, Sendayen BE, Kowal TJ, Wang B, Jones BW, Hu Y, Sun Y. Primary Cilia in Amacrine Cells in Retinal Development. Invest Ophthalmol Vis Sci 2021; 62:15. [PMID: 34241625 PMCID: PMC8287049 DOI: 10.1167/iovs.62.9.15] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Purpose Primary cilia are conserved organelles found in polarized cells within the eye that regulate cell growth, migration, and differentiation. Although the role of cilia in photoreceptors is well-studied, the formation of cilia in other retinal cell types has received little attention. In this study, we examined the ciliary profile focused on the inner nuclear layer of retinas in mice and rhesus macaque primates. Methods Retinal sections or flatmounts from Arl13b-Cetn2 tg transgenic mice were immunostained for cell markers (Pax6, Sox9, Chx10, Calbindin, Calretinin, ChaT, GAD67, Prox1, TH, and vGluT3) and analyzed by confocal microscopy. Primate retinal sections were immunostained for ciliary and cell markers (Pax6 and Arl13b). Optical coherence tomography (OCT) and ERGs were used to assess visual function of Vift88 mice. Results During different stages of mouse postnatal eye development, we found that cilia are present in Pax6-positive amacrine cells, which were also observed in primate retinas. The cilia of subtypes of amacrine cells in mice were shown by immunostaining and electron microscopy. We also removed primary cilia from vGluT3 amacrine cells in mouse and found no significant vision defects. In addition, cilia were present in the outer limiting membrane, suggesting that a population of Müller glial cells forms cilia. Conclusions We report that several subpopulations of amacrine cells in inner nuclear layers of the retina form cilia during early retinal development in mice and primates.
Collapse
Affiliation(s)
- Ke Ning
- Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, California, United States
| | - Brent E Sendayen
- Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, California, United States.,Palo Alto Veterans Administration, Palo Alto, California, United States
| | - Tia J Kowal
- Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, California, United States
| | - Biao Wang
- Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, California, United States
| | - Bryan W Jones
- Moran Eye Center, University of Utah, Salt Lake City, Utah, United States
| | - Yang Hu
- Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, California, United States
| | - Yang Sun
- Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, California, United States.,Palo Alto Veterans Administration, Palo Alto, California, United States
| |
Collapse
|
15
|
Jasso KR, Kamba TK, Zimmerman AD, Bansal R, Engle SE, Everett T, Wu CH, Kulaga H, Reed RR, Berbari NF, McIntyre JC. An N-terminal fusion allele to study melanin concentrating hormone receptor 1. Genesis 2021; 59:e23438. [PMID: 34124835 DOI: 10.1002/dvg.23438] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 06/01/2021] [Accepted: 06/03/2021] [Indexed: 11/10/2022]
Abstract
Cilia on neurons play critical roles in both the development and function of the central nervous system (CNS). While it remains challenging to elucidate the precise roles for neuronal cilia, it is clear that a subset of G-protein-coupled receptors (GPCRs) preferentially localize to the cilia membrane. Further, ciliary GPCR signaling has been implicated in regulating a variety of behaviors. Melanin concentrating hormone receptor 1 (MCHR1), is a GPCR expressed centrally in rodents known to be enriched in cilia. Here we have used MCHR1 as a model ciliary GPCR to develop a strategy to fluorescently tag receptors expressed from the endogenous locus in vivo. Using CRISPR/Cas9, we inserted the coding sequence of the fluorescent protein mCherry into the N-terminus of Mchr1. Analysis of the fusion protein (mCherry MCHR1) revealed its localization to neuronal cilia in the CNS, across multiple developmental time points and in various regions of the adult brain. Our approach simultaneously produced fortuitous in/dels altering the Mchr1 start codon resulting in a new MCHR1 knockout line. Functional studies using electrophysiology show a significant alteration of synaptic strength in MCHR1 knockout mice. A reduction in strength is also detected in mice homozygous for the mCherry insertion, suggesting that while the strategy is useful for monitoring the receptor, activity could be altered. However, both lines should aid in studies of MCHR1 function and contribute to our understanding of MCHR1 signaling in the brain. Additionally, this approach could be expanded to aid in the study of other ciliary GPCRs.
Collapse
Affiliation(s)
- Kalene R Jasso
- Department of Neuroscience and Center for Smell and Taste, University of Florida, Gainesville, Florida, USA.,Graduate Program in Biomedical Sciences, Neuroscience Concentration, University of Florida, Gainesville, Florida, USA
| | - Tisianna K Kamba
- Graduate Program in Biomedical Sciences, Neuroscience Concentration, University of Florida, Gainesville, Florida, USA
| | - Arthur D Zimmerman
- Department of Neuroscience and Center for Smell and Taste, University of Florida, Gainesville, Florida, USA
| | - Ruchi Bansal
- Department of Biology, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana, USA
| | - Staci E Engle
- Department of Biology, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana, USA
| | - Thomas Everett
- Department of Neuroscience and Center for Smell and Taste, University of Florida, Gainesville, Florida, USA
| | - Chang-Hung Wu
- Department of Neuroscience and Center for Smell and Taste, University of Florida, Gainesville, Florida, USA
| | - Heather Kulaga
- Department of Molecular Genetics, Johns Hopkins University, Baltimore, Maryland, USA
| | - Randal R Reed
- Department of Molecular Genetics, Johns Hopkins University, Baltimore, Maryland, USA
| | - Nicolas F Berbari
- Department of Biology, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana, USA
| | - Jeremy C McIntyre
- Department of Neuroscience and Center for Smell and Taste, University of Florida, Gainesville, Florida, USA
| |
Collapse
|
16
|
Bansal R, Engle SE, Kamba TK, Brewer KM, Lewis WR, Berbari NF. Artificial Intelligence Approaches to Assessing Primary Cilia. J Vis Exp 2021:10.3791/62521. [PMID: 33999029 PMCID: PMC8791558 DOI: 10.3791/62521] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Cilia are microtubule based cellular appendages that function as signaling centers for a diversity of signaling pathways in many mammalian cell types. Cilia length is highly conserved, tightly regulated, and varies between different cell types and tissues and has been implicated in directly impacting their signaling capacity. For example, cilia have been shown to alter their lengths in response to activation of ciliary G protein-coupled receptors. However, accurately and reproducibly measuring the lengths of numerous cilia is a time-consuming and labor-intensive procedure. Current approaches are also error and bias prone. Artificial intelligence (Ai) programs can be utilized to overcome many of these challenges due to capabilities that permit assimilation, manipulation, and optimization of extensive data sets. Here, we demonstrate that an Ai module can be trained to recognize cilia in images from both in vivo and in vitro samples. After using the trained Ai to identify cilia, we are able to design and rapidly utilize applications that analyze hundreds of cilia in a single sample for length, fluorescence intensity and co-localization. This unbiased approach increased our confidence and rigor when comparing samples from different primary neuronal preps in vitro as well as across different brain regions within an animal and between animals. Moreover, this technique can be used to reliably analyze cilia dynamics from any cell type and tissue in a high-throughput manner across multiple samples and treatment groups. Ultimately, Ai-based approaches will likely become standard as most fields move toward less biased and more reproducible approaches for image acquisition and analysis.
Collapse
Affiliation(s)
- Ruchi Bansal
- Department of Biology, Indiana University-Purdue University Indianapolis
| | - Staci E Engle
- Department of Biology, Indiana University-Purdue University Indianapolis
| | - Tisianna K Kamba
- Department of Biology, Indiana University-Purdue University Indianapolis
| | - Kathryn M Brewer
- Department of Biology, Indiana University-Purdue University Indianapolis
| | | | - Nicolas F Berbari
- Department of Biology, Indiana University-Purdue University Indianapolis; Stark Neurosciences Research Institute, Indiana University; Center for Diabetes and Metabolic Diseases, Indiana University School of Medicine;
| |
Collapse
|
17
|
Duong Phu M, Bross S, Burkhalter MD, Philipp M. Limitations and opportunities in the pharmacotherapy of ciliopathies. Pharmacol Ther 2021; 225:107841. [PMID: 33771583 DOI: 10.1016/j.pharmthera.2021.107841] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 03/11/2021] [Indexed: 01/10/2023]
Abstract
Ciliopathies are a family of rather diverse conditions, which have been grouped based on the finding of altered or dysfunctional cilia, potentially motile, small cellular antennae extending from the surface of postmitotic cells. Cilia-related disorders include embryonically arising conditions such as Joubert, Usher or Kartagener syndrome, but also afflictions with a postnatal or even adult onset phenotype, i.e. autosomal dominant polycystic kidney disease. The majority of ciliopathies are syndromic rather than affecting only a single organ due to cilia being found on almost any cell in the human body. Overall ciliopathies are considered rare diseases. Despite that, pharmacological research and the strive to help these patients has led to enormous therapeutic advances in the last decade. In this review we discuss new treatment options for certain ciliopathies, give an outlook on promising future therapeutic strategies, but also highlight the limitations in the development of therapeutic approaches of ciliopathies.
Collapse
Affiliation(s)
- Max Duong Phu
- Department of Experimental and Clinical Pharmacology and Pharmacogenomics, Section of Pharmacogenomics, Eberhard-Karls-University of Tübingen, 72074 Tübingen, Germany
| | - Stefan Bross
- Department of Experimental and Clinical Pharmacology and Pharmacogenomics, Section of Pharmacogenomics, Eberhard-Karls-University of Tübingen, 72074 Tübingen, Germany
| | - Martin D Burkhalter
- Department of Experimental and Clinical Pharmacology and Pharmacogenomics, Section of Pharmacogenomics, Eberhard-Karls-University of Tübingen, 72074 Tübingen, Germany
| | - Melanie Philipp
- Department of Experimental and Clinical Pharmacology and Pharmacogenomics, Section of Pharmacogenomics, Eberhard-Karls-University of Tübingen, 72074 Tübingen, Germany.
| |
Collapse
|
18
|
HTR6 and SSTR3 targeting to primary cilia. Biochem Soc Trans 2021; 49:79-91. [PMID: 33599752 DOI: 10.1042/bst20191005] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 12/25/2020] [Accepted: 01/20/2021] [Indexed: 12/30/2022]
Abstract
Primary cilia are hair-like projections of the cell membrane supported by an inner microtubule scaffold, the axoneme, which polymerizes out of a membrane-docked centriole at the ciliary base. By working as specialized signaling compartments, primary cilia provide an optimal environment for many G protein-coupled receptors (GPCRs) and their effectors to efficiently transmit their signals to the rest of the cell. For this to occur, however, all necessary receptors and signal transducers must first accumulate at the ciliary membrane. Serotonin receptor 6 (HTR6) and Somatostatin receptor 3 (SSTR3) are two GPCRs whose signaling in brain neuronal cilia affects cognition and is implicated in psychiatric, neurodegenerative, and oncologic diseases. Over a decade ago, the third intracellular loops (IC3s) of HTR6 and SSTR3 were shown to contain ciliary localization sequences (CLSs) that, when grafted onto non-ciliary GPCRs, could drive their ciliary accumulation. Nevertheless, these CLSs were dispensable for ciliary targeting of HTR6 and SSTR3, suggesting the presence of additional CLSs, which we have recently identified in their C-terminal tails. Herein, we review the discovery and mapping of these CLSs, as well as the state of the art regarding how these CLSs may orchestrate ciliary accumulation of these GPCRs by controlling when and where they interact with the ciliary entry and exit machinery via adaptors such as TULP3, RABL2 and the BBSome.
Collapse
|
19
|
Lee L, Ostrowski LE. Motile cilia genetics and cell biology: big results from little mice. Cell Mol Life Sci 2020; 78:769-797. [PMID: 32915243 DOI: 10.1007/s00018-020-03633-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 08/11/2020] [Accepted: 09/03/2020] [Indexed: 12/13/2022]
Abstract
Our understanding of motile cilia and their role in disease has increased tremendously over the last two decades, with critical information and insight coming from the analysis of mouse models. Motile cilia form on specific epithelial cell types and typically beat in a coordinated, whip-like manner to facilitate the flow and clearance of fluids along the cell surface. Defects in formation and function of motile cilia result in primary ciliary dyskinesia (PCD), a genetically heterogeneous disorder with a well-characterized phenotype but no effective treatment. A number of model systems, ranging from unicellular eukaryotes to mammals, have provided information about the genetics, biochemistry, and structure of motile cilia. However, with remarkable resources available for genetic manipulation and developmental, pathological, and physiological analysis of phenotype, the mouse has risen to the forefront of understanding mammalian motile cilia and modeling PCD. This is evidenced by a large number of relevant mouse lines and an extensive body of genetic and phenotypic data. More recently, application of innovative cell biological techniques to these models has enabled substantial advancement in elucidating the molecular and cellular mechanisms underlying the biogenesis and function of mammalian motile cilia. In this article, we will review genetic and cell biological studies of motile cilia in mouse models and their contributions to our understanding of motile cilia and PCD pathogenesis.
Collapse
Affiliation(s)
- Lance Lee
- Pediatrics and Rare Diseases Group, Sanford Research, Sioux Falls, SD, USA. .,Department of Pediatrics, Sanford School of Medicine of the University of South Dakota, Sioux Falls, SD, USA.
| | - Lawrence E Ostrowski
- Marsico Lung Institute/Cystic Fibrosis Center and Department of Pediatrics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| |
Collapse
|
20
|
Fisher S, Kuna D, Caspary T, Kahn RA, Sztul E. ARF family GTPases with links to cilia. Am J Physiol Cell Physiol 2020; 319:C404-C418. [PMID: 32520609 PMCID: PMC7500214 DOI: 10.1152/ajpcell.00188.2020] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The ADP-ribosylation factor (ARF) superfamily of regulatory GTPases, including both the ARF and ARF-like (ARL) proteins, control a multitude of cellular functions, including aspects of vesicular traffic, lipid metabolism, mitochondrial architecture, the assembly and dynamics of the microtubule and actin cytoskeletons, and other pathways in cell biology. Considering their general utility, it is perhaps not surprising that increasingly ARF/ARLs have been found in connection to primary cilia. Here, we critically evaluate the current knowledge of the roles four ARF/ARLs (ARF4, ARL3, ARL6, ARL13B) play in cilia and highlight key missing information that would help move our understanding forward. Importantly, these GTPases are themselves regulated by guanine nucleotide exchange factors (GEFs) that activate them and by GTPase-activating proteins (GAPs) that act as both effectors and terminators of signaling. We believe that the identification of the GEFs and GAPs and better models of the actions of these GTPases and their regulators will provide a much deeper understanding and appreciation of the mechanisms that underly ciliary functions and the causes of a number of human ciliopathies.
Collapse
Affiliation(s)
- Skylar Fisher
- 1Department of Biochemistry, Emory University
School of Medicine, Atlanta,
Georgia
| | - Damian Kuna
- 2Department of Cell, Developmental and Integrative
Biology, University of Alabama at Birmingham,
Birmingham, Alabama
| | - Tamara Caspary
- 3Department of Human Genetics, Emory
University School of Medicine, Atlanta,
Georgia
| | - Richard A. Kahn
- 1Department of Biochemistry, Emory University
School of Medicine, Atlanta,
Georgia
| | - Elizabeth Sztul
- 2Department of Cell, Developmental and Integrative
Biology, University of Alabama at Birmingham,
Birmingham, Alabama
| |
Collapse
|
21
|
Komarynets O, Chassot A, Bernabeu E, Czogalla J, Roth I, Liaudet N, Prodon F, Loffing J, Feraille E. Aldosterone controls primary cilium length and cell size in renal collecting duct principal cells. FASEB J 2019; 34:2625-2640. [PMID: 31908048 DOI: 10.1096/fj.201901947r] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2019] [Revised: 11/20/2019] [Accepted: 12/05/2019] [Indexed: 12/12/2022]
Abstract
Primary cilia are nonmotile sensory organelles found on the surface of almost all kidney tubule epithelial cells. Being exposed to the tubular lumen, primary cilia are thought to be chemo- and mechanosensors of luminal composition and flux, respectively. We hypothesized that, Na+ transport and primary cilia exist in a sensory functional connection in mature renal tubule epithelial cells. Our results demonstrate that primary cilium length is reduced in mineralocorticoid receptor (MR) knockout (KO) mice in a cell autonomous manner along the aldosterone-sensitive distal nephron (ADSN) compared with wild type (as µm ± SEM; 3.1 ± 0.2 vs 4.0 ± 0.1). In mouse cortical collecting duct (mCCD)cl1 cells, which are a model of collecting duct (CD) principal cells, changes in Na+ transport intensity were found to mediate primary cilium length in response to aldosterone (as µm ± SEM: control: 2.7 ± 0.9 vs aldosterone treated: 3.8 ± 0.8). Cilium length was positively correlated with the availability of IFT88, a major intraflagellar anterograde transport complex B component, which is stabilized in response to exposure to aldosterone treatment. This suggests that the abundance of IFT88 is a regulated, rate limiting factor in the elongation of primary cilia. As previously observed in vivo, aldosterone treatment increased cell volume of cultured CD principal cells. Knockdown of IFT88 prevents ciliogenesis and inhibits the adaptive increase in cell size that was observed in response to aldosterone treatment. In conclusion, our results reveal a functional connection between Na+ transport, primary cilia, and cell size, which may play a key role in the morphological and functional adaptation of the CD to sustained changes in active Na+ reabsorption due to variations in aldosterone secretion.
Collapse
Affiliation(s)
- Olga Komarynets
- Department of Cell Physiology and Metabolism, Faculty of Medicine of Geneva, University Medical Center, University of Geneva, Geneva, Switzerland
| | - Alexandra Chassot
- Department of Cell Physiology and Metabolism, Faculty of Medicine of Geneva, University Medical Center, University of Geneva, Geneva, Switzerland
| | - Eva Bernabeu
- Department of Cell Physiology and Metabolism, Faculty of Medicine of Geneva, University Medical Center, University of Geneva, Geneva, Switzerland
| | - Jan Czogalla
- Institute of Anatomy, University of Zürich, Zürich, Switzerland
| | - Isabelle Roth
- Department of Cell Physiology and Metabolism, Faculty of Medicine of Geneva, University Medical Center, University of Geneva, Geneva, Switzerland
| | - Nicolas Liaudet
- Service of Bioimaging, University of Geneva, Geneva, Switzerland
| | - François Prodon
- Service of Bioimaging, University of Geneva, Geneva, Switzerland
| | | | - Eric Feraille
- Department of Cell Physiology and Metabolism, Faculty of Medicine of Geneva, University Medical Center, University of Geneva, Geneva, Switzerland
| |
Collapse
|
22
|
Portal C, Rompolas P, Lwigale P, Iomini C. Primary cilia deficiency in neural crest cells models anterior segment dysgenesis in mouse. eLife 2019; 8:52423. [PMID: 31845891 PMCID: PMC6946567 DOI: 10.7554/elife.52423] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Accepted: 12/17/2019] [Indexed: 02/06/2023] Open
Abstract
Defects affecting tissues of the anterior segment (AS) of the eye lead to a group of highly debilitating disorders called Anterior Segment Dysgenesis (ASD). Despite the identification of some causative genes, the pathogenesis of ASD remains unclear. Interestingly, several ciliopathies display conditions of the AS. Using conditional targeting of Ift88 with Wnt1-Cre, we show that primary cilia of neural crest cells (NCC), precursors of most AS structures, are indispensable for normal AS development and their ablation leads to ASD conditions including abnormal corneal dimensions, defective iridocorneal angle, reduced anterior chamber volume and corneal neovascularization. Mechanistically, NCC cilia ablation abolishes hedgehog (Hh) signaling in the periocular mesenchyme (POM) canonically activated by choroid-secreted Indian Hh, reduces proliferation of POM cells surrounding the retinal pigment epithelium and decreases the expression of Foxc1 and Pitx2, two transcription factors identified as major ASD causative genes. Thus, we uncovered a signaling axis linking cilia and ASD.
Collapse
Affiliation(s)
- Céline Portal
- Department of Ophthalmology, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Panteleimos Rompolas
- Department of Dermatology, Institute for Regenerative Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, United States
| | - Peter Lwigale
- BioSciences Department, Rice University, Houston, United States
| | - Carlo Iomini
- Department of Ophthalmology, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, United States.,Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, United States
| |
Collapse
|
23
|
Praljak N, Ryan SD, Resnick A. Pulsatile flow through idealized renal tubules: Fluid-structure interaction and dynamic pathologies. MATHEMATICAL BIOSCIENCES AND ENGINEERING : MBE 2019; 17:1787-1807. [PMID: 32233608 PMCID: PMC8533031 DOI: 10.3934/mbe.2020094] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Kidney tubules are lined with flow-sensing structures, yet information about the flow itself is not easily obtained. We aim to generate a multiscale biomechanical model for analyzing fluid flow and fluid-structure interactions within an elastic kidney tubule when the driving pressure is pulsatile. We developed a two-dimensional macroscopic mathematical model of a single fluid-filled tubule corresponding to a distal nephron segment and determined both flow dynamics and wall strains over a range of driving frequencies and wall compliances using finite-element analysis. The results presented here demonstrate good agreement with available analytical solutions and form a foundation for future inclusion of elastohydrodynamic coupling by neighboring tubules. Overall, we are interested in exploring the idea of dynamic pathology to better understand the progression of chronic kidney diseases such as Polycystic Kidney Disease.
Collapse
Affiliation(s)
- Niksa Praljak
- Department of Mathematics and Statistics, Cleveland State University, Cleveland OH 44115, USA
- Department of Physics, Cleveland State University, Cleveland OH 44115, USA
| | - Shawn D. Ryan
- Department of Mathematics and Statistics, Cleveland State University, Cleveland OH 44115, USA
| | - Andrew Resnick
- Department of Physics, Cleveland State University, Cleveland OH 44115, USA
- Center for Gene Regulation in Health and Disease, Cleveland State University, Cleveland OH 44115, USA
| |
Collapse
|
24
|
Yuan X, Liu M, Cao X, Yang S. Ciliary IFT80 regulates dental pulp stem cells differentiation by FGF/FGFR1 and Hh/BMP2 signaling. Int J Biol Sci 2019; 15:2087-2099. [PMID: 31592124 PMCID: PMC6775288 DOI: 10.7150/ijbs.27231] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2018] [Accepted: 02/19/2019] [Indexed: 01/09/2023] Open
Abstract
Primary cilia and intraflagellar transport (IFT) proteins control a wide variety of processes during development and tissue homeostasis. However, their potential roles in the regulation of stem cell differentiation and tooth development remain elusive. Here, we uncovered the critical roles of ciliary IFT80 in cilia formation and differentiation of dental pulp stem cells (DPSCs). IFT80-deficient DPSCs showed reduced fibroblast growth factor receptor 1 (FGFR1) expression, leading to the disruption of FGF2-FGFR1 signaling. We found, during DPSC differentiation, FGF2-FGFR1 signaling induces stress fiber rearrangement to promote cilia elongation, meanwhile stimulates PI3K-AKT signaling to aid Hh/bone morphogenetic protein 2 (BMP2) signaling activation. These signaling pathways and their coupling were disrupted in IFT80-deficient DPSCs, causing impaired differentiation. Our findings revealed a novel mechanism that ciliary protein regulates the odontogenic differentiation of DPSCs through FGF/FGFR1 and Hh/BMP2 signaling.
Collapse
Affiliation(s)
- Xue Yuan
- Department of Oral Biology, School of Dental Medicine, University of Buffalo, State University of New York, Buffalo, NY, United States
| | - Min Liu
- Department of Anatomy & Cell Biology, School of Dental Medicine, University of Pennsylvania, PA, United States
| | - Xu Cao
- Department of Orthopedic Surgery, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Shuying Yang
- Department of Oral Biology, School of Dental Medicine, University of Buffalo, State University of New York, Buffalo, NY, United States
- Department of Anatomy & Cell Biology, School of Dental Medicine, University of Pennsylvania, PA, United States
| |
Collapse
|
25
|
Cui J, Liu Y, Fu BM. Numerical study on the dynamics of primary cilium in pulsatile flows by the immersed boundary-lattice Boltzmann method. Biomech Model Mechanobiol 2019; 19:21-35. [PMID: 31256275 DOI: 10.1007/s10237-019-01192-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 06/21/2019] [Indexed: 10/26/2022]
Abstract
An explicit immersed boundary-lattice Boltzmann method is applied to numerically investigate the dynamics of primary cilium in pulsatile blood flows with two-way fluid-structure interaction considered. To well characterize the effect of cilium basal body on cilium dynamics, the cilium base is modeled as a nonlinear rotational spring attached to the cilium's basal end as proposed by Resnick (Biophys J 109:18-25, 2015. https://doi.org/10.1016/j.bpj.2015.05.031). After several careful validations, the fluid-cilium interaction system is investigated in detail at various pulsatile flow conditions that are characterized by peak Reynolds numbers ([Formula: see text]) and Womersley numbers ([Formula: see text]). The periodic flapping of primary cilium observed in our simulations is very similar to the in vivo ciliary oscillation captured by O'Connor et al. (Cilia 2:8, 2013. https://doi.org/10.1186/2046-2530-2-8). The cilium's dynamics is found to be closely related to the [Formula: see text] and [Formula: see text]. Increase the [Formula: see text] or decrease the [Formula: see text] bring to an increase in the cilium's flapping amplitude, tip angular speed, basal rotation, and maximum tensile stress. It is also demonstrated that by reducing the [Formula: see text] or enhancing the [Formula: see text] to a certain level, one can shift the flapping pattern of cilium from its original two-side one to a one-side one, making the stretch only happen on one particular side. During the flapping process, the location of the maximum tensile stress is not always found at the basal region; instead, it is able to propagate from time to time within a certain distance to the base. Due to the obstruction of the primary cilium, the distribution of wall shear stress no longer remains uniform as in the absence of cilia. It oscillates in space with the minimum magnitude which is always found near where the cilium is located. The presence of cilium also reduces the overall level of wall shear stress, especially at the region near the cilium's anchor point.
Collapse
Affiliation(s)
- Jingyu Cui
- Research Centre for Fluid-Structure Interactions, Department of Mechanical Engineering, The Hong Kong Polytechnic University, Hung Hom, Hong Kong
| | - Yang Liu
- Research Centre for Fluid-Structure Interactions, Department of Mechanical Engineering, The Hong Kong Polytechnic University, Hung Hom, Hong Kong.
| | - Bingmei M Fu
- Department of Biomedical Engineering, City College of New York, New York City, USA
| |
Collapse
|
26
|
Revell DZ, Yoder BK. Intravital visualization of the primary cilium, tubule flow, and innate immune cells in the kidney utilizing an abdominal window imaging approach. Methods Cell Biol 2019; 154:67-83. [PMID: 31493822 DOI: 10.1016/bs.mcb.2019.04.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The renal primary cilium is a small microtubule-based appendage thought to have mechano/chemosensory roles detecting changes in the fluid passing through the nephron. Mutations affecting cilium structure or function of ciliary-localized proteins result in a spectrum of diseases termed ciliopathies, with prevalent phenotypes such as the formation of renal cysts and fibrosis. While many studies have been conducted using fixed kidney sections or live imaging of cells in culture to investigate the cilium, examination in the context of a living murine kidney remains to be conducted. Previously, our lab generated the SSTR3GFP mouse to study cilium dynamics in vivo and found novel cilium behaviors that occurred following alteration of heart rate, blood pressure, and tubule flow. In this manuscript, we utilize multiple transgenic mouse models and an abdominal window imaging approach to observe primary cilia and tubule flow dynamics, immune cell movement, and renal Ca2+ signaling as it occurs in real time within a live mouse kidney. We present this window method as an approach that can be used in combination with various fluorescently labeled transgenic mice to investigate renal physiology, pathology, and function in vivo in longitudinal studies for as long as 5weeks.
Collapse
Affiliation(s)
- Dustin Z Revell
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Bradley K Yoder
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, United States.
| |
Collapse
|
27
|
Nocera S, Simon A, Fiquet O, Chen Y, Gascuel J, Datiche F, Schneider N, Epelbaum J, Viollet C. Somatostatin Serves a Modulatory Role in the Mouse Olfactory Bulb: Neuroanatomical and Behavioral Evidence. Front Behav Neurosci 2019; 13:61. [PMID: 31024270 PMCID: PMC6465642 DOI: 10.3389/fnbeh.2019.00061] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 03/12/2019] [Indexed: 11/30/2022] Open
Abstract
Somatostatin (SOM) and somatostatin receptors (SSTR1-4) are present in all olfactory structures, including the olfactory bulb (OB), where SOM modulates physiological gamma rhythms and olfactory discrimination responses. In this work, histological, viral tracing and transgenic approaches were used to characterize SOM cellular targets in the murine OB. We demonstrate that SOM targets all levels of mitral dendritic processes in the OB with somatostatin receptor 2 (SSTR2) detected in the dendrites of previously uncharacterized mitral-like cells. We show that inhibitory interneurons of the glomerular layer (GL) express SSTR4 while SSTR3 is confined to the granule cell layer (GCL). Furthermore, SOM cells in the OB receive synaptic inputs from olfactory cortical afferents. Behavioral studies demonstrate that genetic deletion of SSTR4, SSTR2 or SOM differentially affects olfactory performance. SOM or SSTR4 deletion have no major effect on olfactory behavioral performances while SSTR2 deletion impacts olfactory detection and discrimination behaviors. Altogether, these results describe novel anatomical and behavioral contributions of SOM, SSTR2 and SSTR4 receptors in olfactory processing.
Collapse
Affiliation(s)
- Sonia Nocera
- INSERM, UMR 894-Center for Psychiatry and Neuroscience (CPN), Paris, France
- Université Paris Descartes-Sorbonne Paris Cité, Paris, France
| | - Axelle Simon
- INSERM, UMR 894-Center for Psychiatry and Neuroscience (CPN), Paris, France
- Université Paris Descartes-Sorbonne Paris Cité, Paris, France
| | - Oriane Fiquet
- INSERM, UMR 894-Center for Psychiatry and Neuroscience (CPN), Paris, France
- Université Paris Descartes-Sorbonne Paris Cité, Paris, France
| | - Ying Chen
- INSERM, UMR 894-Center for Psychiatry and Neuroscience (CPN), Paris, France
- Université Paris Descartes-Sorbonne Paris Cité, Paris, France
| | - Jean Gascuel
- CNRS UMR 6265—Centre des Sciences du Goût et de l’Alimentation (CSGA), Dijon, France
| | - Frédérique Datiche
- CNRS UMR 6265—Centre des Sciences du Goût et de l’Alimentation (CSGA), Dijon, France
| | - Nanette Schneider
- CNRS UMR 6265—Centre des Sciences du Goût et de l’Alimentation (CSGA), Dijon, France
| | - Jacques Epelbaum
- INSERM, UMR 894-Center for Psychiatry and Neuroscience (CPN), Paris, France
- Université Paris Descartes-Sorbonne Paris Cité, Paris, France
| | - Cécile Viollet
- INSERM, UMR 894-Center for Psychiatry and Neuroscience (CPN), Paris, France
- Université Paris Descartes-Sorbonne Paris Cité, Paris, France
| |
Collapse
|
28
|
Cenpj Regulates Cilia Disassembly and Neurogenesis in the Developing Mouse Cortex. J Neurosci 2019; 39:1994-2010. [PMID: 30626697 DOI: 10.1523/jneurosci.1849-18.2018] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Revised: 12/19/2018] [Accepted: 12/24/2018] [Indexed: 11/21/2022] Open
Abstract
Primary cilia are microtubule-based protuberances that project from the eukaryotic cell body to sense the extracellular environment. Ciliogenesis is closely correlated to the cell cycle and defects of cilia are related to human systemic diseases such as primary ciliary dyskinesia. However, the role of ciliogenesis in cortical development remains unclear. Here, we demonstrate that Cenpj, a protein that is required for centriole biogenesis, plays a role in regulating cilium disassembly in vivo Depletion of Cenpj in neural progenitor cells results in long cilia and abnormal cilia disassembly. Radial glial cells Cenpj depletion exhibit uncompleted cell division, reduced cell proliferation, and increased cell apoptosis in the developing mouse cerebrum cortex, leading to microcephaly. In addition, Cenpj depletion causes long and thin primary cilia and motile cilia in adult neural stem cells and reduced cell proliferation in the subventricular zone. Furthermore, we show that Cenpj regulates cilia disassembly and neurogenesis through Kif2a, a plus-end-directed motor protein. These data collected from mice of both sexes provide insights into how ciliogenesis plays roles in cortical development and how primary microcephaly is induced by Cenpj mutations in humans.SIGNIFICANCE STATEMENT Autosomal recessive primary microcephaly is a neurodevelopmental disorder with the major symptoms of reduction of circumference of the head, brain volume, and cortex thickness with normal brain architecture in birth. We used conditional Cenpj deletion mice and found that neural progenitor cells (NPCs) exhibited long primary cilia and abnormal cilium appendages. The defective cilium disassembly caused by Cenpj depletion might correlate to reduced cell proliferation, uncompleted cell division, cell apoptosis, and microcephaly in mice. Cenpj also regulates the cilium structure of adult neural stem cells and adult neurogenesis in mice. Additionally, our results illustrate that Cenpj regulates cilia disassembly and neurogenesis through Kif2a, indicating that primary cilia dynamics play a crucial role in NPC mitosis and adult neurogenesis.
Collapse
|
29
|
Kilander MBC, Wang CH, Chang CH, Nestor JE, Herold K, Tsai JW, Nestor MW, Lin YC. A rare human CEP290 variant disrupts the molecular integrity of the primary cilium and impairs Sonic Hedgehog machinery. Sci Rep 2018; 8:17335. [PMID: 30478281 PMCID: PMC6255789 DOI: 10.1038/s41598-018-35614-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 11/07/2018] [Indexed: 12/25/2022] Open
Abstract
The primary cilium is a microtubule-enriched cell-communication organelle that participates in mechanisms controlling tissue development and maintenance, including cerebellar architecture. Centrosomal protein of 290 kDa (CEP290) is a protein important for centrosomal function and ciliogenesis. Mutations in CEP290 have been linked to a group of multi-organ disorders - termed ciliopathies. The neurophysiological deficits observed in ciliopathies are sometimes associated with the progression of autistic traits. Here, the cellular function of two rare variants of CEP290 identified from recent exome sequencing of autistic individuals are investigated. Cells expressing Cep290 carrying the missense mutation R1747Q in mouse exhibited a defective Sonic hedgehog (Shh) signalling response, mislocalisation of the Shh receptor Smoothened (Smo), and dysregulation of ciliary protein mobility, which ultimately disrupted the proliferation of cerebellar granule progenitors (CGPs). This data was furthermore corroborated in an autism patient-derived iPSC line harbouring the R1746Q rare CEP290 variant. Evidence from this study suggests that the R1746Q mutation interferes with the function of CEP290 to maintain the ciliary diffusion barrier and disrupts the integrity of the molecular composition in the primary cilium, which may contribute to alterations in neuroarchitecture.
Collapse
Affiliation(s)
| | - Chun-Hung Wang
- Institute of Brain Science, School of Medicine, National Yang-Ming University, Taipei, 112, Taiwan
| | - Chia-Hsiang Chang
- Institute of Brain Science, School of Medicine, National Yang-Ming University, Taipei, 112, Taiwan
- Taiwan International Graduate Program (TIGP) in Molecular Medicine, National Yang-Ming University and Academia Sinica, Taipei, Taiwan
| | - Jonathan E Nestor
- Program in Neuroscience, Hussman Institute for Autism, Baltimore, MD, 21201, USA
| | - Kevin Herold
- Program in Molecular Medicine, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
| | - Jin-Wu Tsai
- Institute of Brain Science, School of Medicine, National Yang-Ming University, Taipei, 112, Taiwan
- Brain Research Center (BRC), and Biophotonics and Molecular Imaging Research Center (BMIRC), National Yang-Ming University, Taipei, 112, Taiwan
| | - Michael W Nestor
- Program in Neuroscience, Hussman Institute for Autism, Baltimore, MD, 21201, USA
| | - Yu-Chih Lin
- Program in Neuroscience, Hussman Institute for Autism, Baltimore, MD, 21201, USA.
| |
Collapse
|
30
|
Hoang-Minh LB, Dutra-Clarke M, Breunig JJ, Sarkisian MR. Glioma cell proliferation is enhanced in the presence of tumor-derived cilia vesicles. Cilia 2018; 7:6. [PMID: 30410731 PMCID: PMC6219037 DOI: 10.1186/s13630-018-0060-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 10/24/2018] [Indexed: 11/10/2022] Open
Abstract
Background The mechanisms by which primary cilia affect glioma pathogenesis are unclear. Depending on the glioma cell line, primary cilia can promote or inhibit tumor development. Here, we used piggyBac-mediated transgenesis to generate patient-derived glioblastoma (GBM) cell lines that stably express Arl13b:GFP in their cilia. This allowed us to visualize and analyze the behavior of cilia and ciliated cells during live GBM cell proliferation. Results Time-lapse imaging of Arl13b:GFP+ cilia revealed their dynamic behaviors, including distal tip excision into the extracellular milieu. Recent studies of non-cancerous cells indicate that this process occurs during the G0 phase, prior to cilia resorption and cell cycle re-entry, and requires ciliary recruitment of F-actin and actin regulators. Similarly, we observed ciliary buds associated with Ki67- cells as well as scattered F-actin+ cilia, suggesting that quiescent GBM cells may also utilize an actin network-based mechanism for ciliary tip excision. Notably, we found that the proliferation of ciliated GBM cells was promoted by exposing them to conditioned media obtained from ciliated cell cultures when compared to conditioned media collected from cilia-defective cell cultures (depleted in either KIF3A or IFT88 using CRISPR/Cas9). These results suggest that GBM cilia may release mitogenic vesicles carrying factors that promote tumor cell proliferation. Although Arl13b is implicated in tumor growth, our data suggest that Arl13b released from GBM cilia does not mediate tumor cell proliferation. Conclusion Collectively, our results indicate that ciliary vesicles may represent a novel mode of intercellular communication within tumors that contributes to GBM pathogenesis. The mitogenic capacity of GBM ciliary vesicles and the molecular mediators of this phenomenon requires further investigation.
Collapse
Affiliation(s)
- Lan B Hoang-Minh
- 1Department of Neuroscience, University of Florida College of Medicine, McKnight Brain Institute, Gainesville, FL 32610 USA.,2Preston A. Wells, Jr. Center for Brain Tumor Therapy, University of Florida College of Medicine, McKnight Brain Institute, Gainesville, FL 32610 USA
| | - Marina Dutra-Clarke
- 3Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048 USA.,4Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA 90048 USA.,5Samuel Oschin Comprehensive Cancer Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048 USA
| | - Joshua J Breunig
- 3Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048 USA.,4Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA 90048 USA.,5Samuel Oschin Comprehensive Cancer Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048 USA
| | - Matthew R Sarkisian
- 1Department of Neuroscience, University of Florida College of Medicine, McKnight Brain Institute, Gainesville, FL 32610 USA.,2Preston A. Wells, Jr. Center for Brain Tumor Therapy, University of Florida College of Medicine, McKnight Brain Institute, Gainesville, FL 32610 USA
| |
Collapse
|
31
|
Sterpka A, Chen X. Neuronal and astrocytic primary cilia in the mature brain. Pharmacol Res 2018; 137:114-121. [PMID: 30291873 PMCID: PMC6410375 DOI: 10.1016/j.phrs.2018.10.002] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 09/28/2018] [Accepted: 10/01/2018] [Indexed: 12/17/2022]
Abstract
Primary cilia are tiny microtubule-based signaling devices that regulate a variety of physiological functions, including metabolism and cell division. Defects in primary cilia lead to a myriad of diseases in humans such as obesity and cancers. In the mature brain, both neurons and astrocytes contain a single primary cilium. Although neuronal primary cilia are not directly involved in synaptic communication, their pathophysiological impacts on obesity and mental disorders are well recognized. In contrast, research on astrocytic primary cilia lags far behind. Currently, little is known about their functions and molecular pathways in the mature brain. Unlike neurons, postnatal astrocytes retain the capacity of cell division and can become reactive and proliferate in response to various brain insults such as epilepsy, ischemia, traumatic brain injury, and neurodegenerative β-amyloid plaques. Since primary cilia derive from the mother centrioles, astrocyte proliferation must occur in coordination with the dismantling and ciliogenesis of astrocyte cilia. In this regard, the functions, signal pathways, and structural dynamics of neuronal and astrocytic primary cilia are fundamentally different. Here we discuss and compare the current understanding of neuronal and astrocytic primary cilia.
Collapse
Affiliation(s)
- Ashley Sterpka
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, Durham, NH, 03824, United States
| | - Xuanmao Chen
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, Durham, NH, 03824, United States.
| |
Collapse
|
32
|
Venzac B, Madoun R, Benarab T, Monnier S, Cayrac F, Myram S, Leconte L, Amblard F, Viovy JL, Descroix S, Coscoy S. Engineering small tubes with changes in diameter for the study of kidney cell organization. BIOMICROFLUIDICS 2018; 12:024114. [PMID: 29657657 PMCID: PMC5882411 DOI: 10.1063/1.5025027] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 03/19/2018] [Indexed: 05/08/2023]
Abstract
Multicellular tubes are structures ubiquitously found during development and in adult organisms. Their topologies (diameter, direction or branching), together with their mechanical characteristics, play fundamental roles in organ function and in the emergence of pathologies. In tubes of micrometric range diameters, typically found in the vascular system, renal tubules or excretory ducts, cells are submitted to a strong curvature and confinement effects in addition to flow. Then, small tubes with change in diameter are submitted to a local gradient of shear stress and curvature, which may lead to complex mechanotransduction responses along tubes, and may be involved in the onset or propagation of cystic or obstructive pathologies. We describe here a simple method to build a microfluidic device that integrates cylindrical channels with changes in diameter that mimic in vivo tube geometries. This microfabrication approach is based on molding of etched tungsten wires, which can achieve on a flexible way any change in diameter in a polydimethylsiloxane (PDMS) microdevice. The interest of this biomimetic multitube system has been evidenced by reproducing renal tubules on chip. In particular, renal cell lines were successfully seeded and grown in PDMS circular tubes with a transition between 80 μm and 50 μm diameters. Thanks to this biomimetic platform, the effect of the tube curvature has been investigated especially regarding cell morphology and orientation. The effect of shear stress on confluent cells has also been assessed simultaneously in both parts of tubes. It is thus possible to study interconnected cell response to differential constraints which is of central importance when mimicking tubes present in the organism.
Collapse
Affiliation(s)
| | | | | | | | | | | | - Ludovic Leconte
- Institut Curie, PSL Research University, CNRS UMR 144, 75005 Paris, France
| | | | | | | | - Sylvie Coscoy
- Authors to whom correspondence should be addressed: and
| |
Collapse
|
33
|
Agbu SO, Liang Y, Liu A, Anderson KV. The small GTPase RSG1 controls a final step in primary cilia initiation. J Cell Biol 2017; 217:413-427. [PMID: 29038301 PMCID: PMC5748968 DOI: 10.1083/jcb.201604048] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Revised: 08/18/2016] [Accepted: 09/21/2017] [Indexed: 12/11/2022] Open
Abstract
Primary cilia are essential for normal development and tissue homeostasis, but the mechanisms that remodel the centriole to promote cilia initiation are not well understood. Agbu et al. report that mouse RSG1, a small GTPase, regulates a late step in cilia initiation, downstream of TTBK2 and the CPLANE protein INTU. Primary cilia, which are essential for normal development and tissue homeostasis, are extensions of the mother centriole, but the mechanisms that remodel the centriole to promote cilia initiation are poorly understood. Here we show that mouse embryos that lack the small guanosine triphosphatase RSG1 die at embryonic day 12.5, with developmental abnormalities characteristic of decreased cilia-dependent Hedgehog signaling. Rsg1 mutant embryos have fewer primary cilia than wild-type embryos, but the cilia that form are of normal length and traffic Hedgehog pathway proteins within the cilium correctly. Rsg1 mother centrioles recruit proteins required for cilia initiation and dock onto ciliary vesicles, but axonemal microtubules fail to elongate normally. RSG1 localizes to the mother centriole in a process that depends on tau tubulin kinase 2 (TTBK2), the CPLANE complex protein Inturned (INTU), and its own GTPase activity. The data suggest a specific role for RSG1 in the final maturation of the mother centriole and ciliary vesicle that allows extension of the ciliary axoneme.
Collapse
Affiliation(s)
- Stephanie O Agbu
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY.,Biochemistry, Cell and Molecular Biology Program, Weill Graduate School of Medical Sciences of Cornell University, New York, NY
| | - Yinwen Liang
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Aimin Liu
- Department of Biology, Eberly College of Science, The Pennsylvania State University, University Park, PA
| | - Kathryn V Anderson
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY
| |
Collapse
|
34
|
Adenylyl cyclase 5 deficiency reduces renal cyclic AMP and cyst growth in an orthologous mouse model of polycystic kidney disease. Kidney Int 2017; 93:403-415. [PMID: 29042084 DOI: 10.1016/j.kint.2017.08.005] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Revised: 07/24/2017] [Accepted: 08/03/2017] [Indexed: 11/22/2022]
Abstract
Cyclic AMP promotes cyst growth in polycystic kidney disease (PKD) by stimulating cell proliferation and fluid secretion. Previously, we showed that the primary cilium of renal epithelial cells contains a cAMP regulatory complex comprising adenylyl cyclases 5 and 6 (AC5/6), polycystin-2, A-kinase anchoring protein 150, protein kinase A, and phosphodiesterase 4C. In Kif3a mutant cells that lack primary cilia, the formation of this regulatory complex is disrupted and cAMP levels are increased. Inhibition of AC5 reduces cAMP levels in Kif3a mutant cells, suggesting that AC5 may mediate the increase in cAMP in PKD. Here, we examined the role of AC5 in an orthologous mouse model of PKD caused by kidney-specific ablation of Pkd2. Knockdown of AC5 with siRNA attenuated the increase in cAMP levels in Pkd2-deficient renal epithelial cells. Levels of cAMP and AC5 mRNA transcripts were elevated in the kidneys of mice with collecting duct-specific ablation of Pkd2. Compared with Pkd2 single mutant mice, AC5/Pkd2 double mutant mice had less kidney enlargement, lower cyst index, reduced kidney injury, and improved kidney function. Importantly, cAMP levels and cAMP-dependent signaling were reduced in the kidneys of AC5/Pkd2 double mutant compared to the kidneys of Pkd2 single mutant mice. Additionally, we localized endogenous AC5 in the primary cilium of renal epithelial cells and showed that ablation of AC5 reduced ciliary elongation in the kidneys of Pkd2 mutant mice. Thus, AC5 contributes importantly to increased renal cAMP levels and cyst growth in Pkd2 mutant mice, and inhibition of AC5 may be beneficial in the treatment of PKD.
Collapse
|
35
|
Guo J, Otis JM, Higginbotham H, Monckton C, Cheng J, Asokan A, Mykytyn K, Caspary T, Stuber GD, Anton ES. Primary Cilia Signaling Shapes the Development of Interneuronal Connectivity. Dev Cell 2017; 42:286-300.e4. [PMID: 28787594 DOI: 10.1016/j.devcel.2017.07.010] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Revised: 05/18/2017] [Accepted: 07/12/2017] [Indexed: 01/06/2023]
Abstract
Appropriate growth and synaptic integration of GABAergic inhibitory interneurons are essential for functional neural circuits in the brain. Here, we demonstrate that disruption of primary cilia function following the selective loss of ciliary GTPase Arl13b in interneurons impairs interneuronal morphology and synaptic connectivity, leading to altered excitatory/inhibitory activity balance. The altered morphology and connectivity of cilia mutant interneurons and the functional deficits are rescued by either chemogenetic activation of ciliary G-protein-coupled receptor (GPCR) signaling or the selective induction of Sstr3, a ciliary GPCR, in Arl13b-deficient cilia. Our results thus define a specific requirement for primary cilia-mediated GPCR signaling in interneuronal connectivity and inhibitory circuit formation.
Collapse
Affiliation(s)
- Jiami Guo
- UNC Neuroscience Center, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA; Department of Cell Biology and Physiology, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA
| | - James M Otis
- UNC Neuroscience Center, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA; Department of Psychiatry, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA
| | - Holden Higginbotham
- UNC Neuroscience Center, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA; Department of Cell Biology and Physiology, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA
| | - Chase Monckton
- UNC Neuroscience Center, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA
| | - JrGang Cheng
- UNC Neuroscience Center, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA
| | - Aravind Asokan
- Department of Genetics and Gene Therapy Center, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA
| | - Kirk Mykytyn
- Department of Biological Chemistry and Pharmacology, Neuroscience Research Institute, The Ohio State University, Columbus, OH 43210, USA
| | - Tamara Caspary
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Garret D Stuber
- UNC Neuroscience Center, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA; Department of Cell Biology and Physiology, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA; Department of Psychiatry, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA
| | - E S Anton
- UNC Neuroscience Center, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA; Department of Cell Biology and Physiology, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA.
| |
Collapse
|
36
|
Nag S, Resnick A. Biophysics and biofluid dynamics of primary cilia: evidence for and against the flow-sensing function. Am J Physiol Renal Physiol 2017. [DOI: 10.1152/ajprenal.00172.2017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Primary cilia have been called “the forgotten organelle” for over 20 yr. As cilia now have their own journal and several books devoted to their study, perhaps it is time to reconsider the moniker “forgotten organelle.” In fact, during the drafting of this review, 12 relevant publications have been issued; we therefore apologize in advance for any relevant work we inadvertently omitted. What purpose is yet another ciliary review? The primary goal of this review is to specifically examine the evidence for and against the hypothesized flow-sensing function of primary cilia expressed by differentiated epithelia within a kidney tubule, bringing together differing disciplines and their respective conceptual and experimental approaches. We will show that understanding the biophysics/biomechanics of primary cilia provides essential information for understanding any potential role of ciliary function in disease. We will summarize experimental and mathematical models used to characterize renal fluid flow and incident force on primary cilia and to characterize the mechanical response of cilia to an externally applied force and discuss possible ciliary-mediated cell signaling pathways triggered by flow. Throughout, we stress the importance of separating the effects of fluid shear and stretch from the action of hydrodynamic drag.
Collapse
Affiliation(s)
- Subhra Nag
- Department of Biology, Geology, and Environmental Sciences, Cleveland State University, Cleveland, Ohio
| | - Andrew Resnick
- Department of Biology, Geology, and Environmental Sciences, Cleveland State University, Cleveland, Ohio
- Department of Physics, Cleveland State University, Cleveland, Ohio; and
- Center for Gene Regulation in Health and Disease, Cleveland State University, Cleveland, Ohio
| |
Collapse
|
37
|
Takao D, Wang L, Boss A, Verhey KJ. Protein Interaction Analysis Provides a Map of the Spatial and Temporal Organization of the Ciliary Gating Zone. Curr Biol 2017; 27:2296-2306.e3. [PMID: 28736169 DOI: 10.1016/j.cub.2017.06.044] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 05/09/2017] [Accepted: 06/16/2017] [Indexed: 11/19/2022]
Abstract
The motility and signaling functions of the primary cilium require a unique protein and lipid composition that is determined by gating mechanisms localized at the base of the cilium. Several protein complexes localize to the gating zone and may regulate ciliary protein composition; however, the mechanisms of ciliary gating and the dynamics of the gating components are largely unknown. Here, we used the BiFC (bimolecular fluorescence complementation) assay and report for the first time on the protein-protein interactions that occur between ciliary gating components and transiting cargoes during ciliary entry. We find that the nucleoporin Nup62 and the C termini of the nephronophthisis (NPHP) proteins NPHP4 and NPHP5 interact with the axoneme-associated kinesin-2 motor KIF17 and thus spatially map to the inner region of the ciliary gating zone. Nup62 and NPHP4 exhibit rapid turnover at the transition zone and thus define dynamic components of the gate. We find that B9D1, AHI1, and the N termini of NPHP4 and NPHP5 interact with the transmembrane protein SSTR3 and thus spatially map to the outer region of the ciliary gating zone. B9D1, AHI1, and NPHP5 exhibit little to no turnover at the transition zone and thus define components of a stable gating structure. These data provide the first comprehensive map of the molecular orientations of gating zone components along the inner-to-outer axis of the ciliary gating zone. These results advance our understanding of the functional roles of gating zone components in regulating ciliary protein composition.
Collapse
Affiliation(s)
- Daisuke Takao
- Department of Cell and Developmental Biology, University of Michigan Medical School, 109 Zina Pitcher Place, Ann Arbor, MI 48109, USA
| | - Liang Wang
- Department of Cell and Developmental Biology, University of Michigan Medical School, 109 Zina Pitcher Place, Ann Arbor, MI 48109, USA; The Key Laboratory of Biotechnology for Medicinal Plant of Jiangsu Province, School of Life Science, Jiangsu Normal University, 101 Shanghai Road, Tongshan District, Xuzhou 221116, China
| | - Allison Boss
- Department of Cell and Developmental Biology, University of Michigan Medical School, 109 Zina Pitcher Place, Ann Arbor, MI 48109, USA
| | - Kristen J Verhey
- Department of Cell and Developmental Biology, University of Michigan Medical School, 109 Zina Pitcher Place, Ann Arbor, MI 48109, USA.
| |
Collapse
|
38
|
Abstract
Primary cilia are small, antenna-like structures that detect mechanical and chemical cues and transduce extracellular signals. While mammalian primary cilia were first reported in the late 1800s, scientific interest in these sensory organelles has burgeoned since the beginning of the twenty-first century with recognition that primary cilia are essential to human health. Among the most common clinical manifestations of ciliary dysfunction are renal cysts. The molecular mechanisms underlying renal cystogenesis are complex, involving multiple aberrant cellular processes and signaling pathways, while initiating molecular events remain undefined. Autosomal Dominant Polycystic Kidney Disease is the most common renal cystic disease, caused by disruption of polycystin-1 and polycystin-2 transmembrane proteins, which evidence suggests must localize to primary cilia for proper function. To understand how the absence of these proteins in primary cilia may be remediated, we review intracellular trafficking of polycystins to the primary cilium. We also examine the controversial mechanisms by which primary cilia transduce flow-mediated mechanical stress into intracellular calcium. Further, to better understand ciliary function in the kidney, we highlight the LKB1/AMPK, Wnt, and Hedgehog developmental signaling pathways mediated by primary cilia and misregulated in renal cystic disease.
Collapse
|
39
|
Carrisoza-Gaytán R, Wang L, Schreck C, Kleyman TR, Wang WH, Satlin LM. The mechanosensitive BKα/β1 channel localizes to cilia of principal cells in rabbit cortical collecting duct (CCD). Am J Physiol Renal Physiol 2016; 312:F143-F156. [PMID: 27806944 DOI: 10.1152/ajprenal.00256.2016] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Revised: 10/12/2016] [Accepted: 10/26/2016] [Indexed: 11/22/2022] Open
Abstract
Within the CCD of the distal nephron of the rabbit, the BK (maxi K) channel mediates Ca2+- and/or stretch-dependent flow-induced K+ secretion (FIKS) and contributes to K+ adaptation in response to dietary K+ loading. An unresolved question is whether BK channels in intercalated cells (ICs) and/or principal cells (PCs) in the CCD mediate these K+ secretory processes. In support of a role for ICs in FIKS is the higher density of immunoreactive apical BKα (pore-forming subunit) and functional BK channel activity than detected in PCs, and an increase in IC BKα expression in response to a high-K+ diet. PCs possess a single apical cilium which has been proposed to serve as a mechanosensor; direct manipulation of cilia leads to increases in cell Ca2+ concentration, albeit of nonciliary origin. Immunoperfusion of isolated and fixed CCDs isolated from control K+-fed rabbits with channel subunit-specific antibodies revealed colocalization of immunodetectable BKα- and β1-subunits in cilia as well as on the apical membrane of cilia-expressing PCs. Ciliary BK channels were more easily detected in rabbits fed a low-K+ vs. high-K+ diet. Single-channel recordings of cilia revealed K+ channels with conductance and kinetics typical of the BK channel. The observations that 1) FIKS was preserved but 2) the high-amplitude Ca2+ peak elicited by flow was reduced in microperfused CCDs subject to pharmacological deciliation suggest that cilia BK channels do not contribute to K+ secretion in this segment, but that cilia serve as modulators of cell signaling.
Collapse
Affiliation(s)
| | - Lijun Wang
- Department of Pharmacology, New York Medical College, Valhalla, New York
| | - Carlos Schreck
- Servicio de Nefrologia-Hospital Italiano de Buenos Aires, Buenos Aires, Argentina
| | - Thomas R Kleyman
- Departments of Medicine, Cell Biology, and Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania; and
| | - Wen-Hui Wang
- Department of Pharmacology, New York Medical College, Valhalla, New York
| | - Lisa M Satlin
- Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, New York;
| |
Collapse
|
40
|
Leventea E, Hazime K, Zhao C, Malicki J. Analysis of cilia structure and function in zebrafish. Methods Cell Biol 2016; 133:179-227. [PMID: 27263414 DOI: 10.1016/bs.mcb.2016.04.016] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Cilia are microtubule-based protrusions on the surface of most eukaryotic cells. They are found in most, if not all, vertebrate organs. Prominent cilia form in sensory structures, the eye, the ear, and the nose, where they are crucial for the detection of environmental stimuli, such as light and odors. Cilia are also involved in developmental processes, including left-right asymmetry formation, limb morphogenesis, and the patterning of neurons in the neural tube. Some cilia, such as those found in nephric ducts, are thought to have mechanosensory roles. Zebrafish proved very useful in genetic analysis and imaging of cilia-related processes, and in the modeling of mechanisms behind human cilia abnormalities, known as ciliopathies. A number of zebrafish defects resemble those seen in human ciliopathies. Forward and reverse genetic strategies generated a wide range of cilia mutants in zebrafish, which can be studied using sophisticated genetic and imaging approaches. In this chapter, we provide a set of protocols to examine cilia morphology, motility, and cilia-related defects in a variety of organs, focusing on the embryo and early postembryonic development.
Collapse
Affiliation(s)
- E Leventea
- The University of Sheffield, Sheffield, United Kingdom
| | - K Hazime
- The University of Sheffield, Sheffield, United Kingdom
| | - C Zhao
- The University of Sheffield, Sheffield, United Kingdom; Ocean University of China, Qingdao, China
| | - J Malicki
- The University of Sheffield, Sheffield, United Kingdom
| |
Collapse
|
41
|
Delling M, Indzhykulian AA, Liu X, Li Y, Xie T, Corey DP, Clapham DE. Primary cilia are not calcium-responsive mechanosensors. Nature 2016; 531:656-60. [PMID: 27007841 PMCID: PMC4851444 DOI: 10.1038/nature17426] [Citation(s) in RCA: 259] [Impact Index Per Article: 32.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Accepted: 02/16/2016] [Indexed: 01/09/2023]
Abstract
Primary cilia are solitary, generally non-motile, hair-like protrusions that extend from the surface of cells between cell divisions. Their antenna-like structure leads naturally to the assumption that they sense the surrounding environment, the most common hypothesis being sensation of mechanical force through calcium-permeable ion channels within the cilium1. This Ca2+- Responsive MechanoSensor (CaRMS) hypothesis for primary cilia has been invoked to explain a large range of biological responses, from control of left-right axis determination in embryonic development to adult progression of polycystic kidney disease and some cancers2,3. Here, we report the complete lack of mechanically induced calcium increases in primary cilia, in tissues upon which this hypothesis has been based. First, we developed a transgenic mouse, Arl13b-mCherry-GECO1.2, expressing a ratiometric genetically encoded calcium indicator (GECI) in all primary cilia. We then measured responses to flow in primary cilia of cultured kidney epithelial cells, kidney thick ascending tubules, crown cells of the embryonic node, kinocilia of inner ear hair cells, and several cell lines. Cilia-specific Ca2+ influxes were not observed in physiological or even highly supraphysiological levels of fluid flow. We conclude that mechanosensation, if it originates in primary cilia, is not via calcium signaling.
Collapse
Affiliation(s)
- M Delling
- Department of Cardiology, Howard Hughes Medical Institute, Boston Children's Hospital, Boston, Massachusetts 02115, USA
| | - A A Indzhykulian
- Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - X Liu
- Department of Cardiology, Howard Hughes Medical Institute, Boston Children's Hospital, Boston, Massachusetts 02115, USA
| | - Y Li
- Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - T Xie
- Image and Data Analysis Core (IDAC), Harvard Medical School, Boston, Massachusetts 02115, USA
| | - D P Corey
- Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - D E Clapham
- Department of Cardiology, Howard Hughes Medical Institute, Boston Children's Hospital, Boston, Massachusetts 02115, USA.,Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Boston, Massachusetts 02115, USA
| |
Collapse
|
42
|
Bolisetty S, Traylor A, Joseph R, Zarjou A, Agarwal A. Proximal tubule-targeted heme oxygenase-1 in cisplatin-induced acute kidney injury. Am J Physiol Renal Physiol 2016; 310:F385-94. [PMID: 26672618 PMCID: PMC4868370 DOI: 10.1152/ajprenal.00335.2015] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Accepted: 12/14/2015] [Indexed: 12/13/2022] Open
Abstract
Heme oxygenase-1 (HO-1) is a cytoprotective enzyme that catalyzes the breakdown of heme to biliverdin, carbon monoxide, and iron. The beneficial effects of HO-1 expression are not merely due to degradation of the pro-oxidant heme but are also credited to the by-products that have potent, protective effects, including antioxidant, anti-inflammatory, and prosurvival properties. This is well reflected in the preclinical animal models of injury in both renal and nonrenal settings. However, excessive accumulation of the by-products can be deleterious and lead to mitochondrial toxicity and oxidative stress. Therefore, use of the HO system in alleviating injury merits a targeted approach. Based on the higher susceptibility of the proximal tubule segment of the nephron to injury, we generated transgenic mice using cre-lox technology to enable manipulation of HO-1 (deletion or overexpression) in a cell-specific manner. We demonstrate the validity and feasibility of these mice by breeding them with proximal tubule-specific Cre transgenic mice. Similar to previous reports using chemical modulators and global transgenic mice, we demonstrate that whereas deletion of HO-1, specifically in the proximal tubules, aggravates structural and functional damage during cisplatin nephrotoxicity, selective overexpression of HO-1 in proximal tubules is protective. At the cellular level, cleaved caspase-3 expression, a marker of apoptosis, and p38 signaling were modulated by HO-1. Use of these transgenic mice will aid in the evaluation of the effects of cell-specific HO-1 expression in response to injury and assist in the generation of targeted approaches that will enhance recovery with reduced, unwarranted adverse effects.
Collapse
Affiliation(s)
- Subhashini Bolisetty
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama; Nephrology Research and Training Center, University of Alabama at Birmingham, Birmingham, Alabama; Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama; and
| | - Amie Traylor
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama; Nephrology Research and Training Center, University of Alabama at Birmingham, Birmingham, Alabama
| | - Reny Joseph
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama; Nephrology Research and Training Center, University of Alabama at Birmingham, Birmingham, Alabama
| | - Abolfazl Zarjou
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama; Nephrology Research and Training Center, University of Alabama at Birmingham, Birmingham, Alabama
| | - Anupam Agarwal
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama; Nephrology Research and Training Center, University of Alabama at Birmingham, Birmingham, Alabama; Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama; and Birmingham Veterans Administration Medical Center, Birmingham, Alabama
| |
Collapse
|
43
|
Abstract
Neuroscientists have been captivated by cilia ever since these slender, microtubule-based projections on the cell body were found to play critical roles in neuronal specification, maintenance, and function. In mammals, the most common cilia marker, acetylated α-tubulin, is extremely difficult to detect in neuronal cilia. Here, we describe methods to detect neuronal cilia in culture, in fixed sections, and in vivo, taking advantage of transgenic mice carrying fluorescently tagged cilia proteins.
Collapse
|
44
|
Tsuji T, Matsuo K, Nakahari T, Marunaka Y, Yokoyama T. Structural basis of the Inv compartment and ciliary abnormalities in Inv/nphp2 mutant mice. Cytoskeleton (Hoboken) 2015; 73:45-56. [PMID: 26615802 DOI: 10.1002/cm.21264] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Revised: 11/19/2015] [Accepted: 11/23/2015] [Indexed: 01/17/2023]
Abstract
The primary cilium is a hair like structure protruding from most mammalian cells. The basic design of the primary cilium consists of a nine microtubule doublet structure (the axoneme). The Inv compartment, a distinct proximal segment of the ciliary body, is defined as the region in which the Inv protein is localized. Inv gene is a responsible gene for human nephronophthisis type2 (NPHP2). Here, we show that renal cilia have a short proximal microtubule doublet region and a long distal microtubule singlet region. The length of the Inv compartment was similar to that of the microtubule doublet region, suggesting a possibility that the doublet region is the structural basis of the Inv compartment. Respiratory cilia of inv mouse mutants had ciliary rootlet malformation and showed reduced ciliary beating frequency and ciliary beating angle, which may explain recurrent bronchitis in NPHP2 patients. In multiciliated tracheal cells, most Inv proteins were retained in the basal body and did not accumulate in the Inv compartment. These results suggest that the machinery to transport and retain Inv in cilia is different between renal and tracheal cilia and that Inv may function in the basal body of tracheal cells.
Collapse
Affiliation(s)
- Takuma Tsuji
- Division of Anatomy and Developmental Biology, Department of Anatomy, Graduate School of Medicine, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Kazuhiko Matsuo
- Division of Anatomy and Developmental Biology, Department of Anatomy, Graduate School of Medicine, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Takashi Nakahari
- Division of Molecular Cell Physiology, Department of Physiology, Graduate School of Medicine, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Yoshinori Marunaka
- Division of Molecular Cell Physiology, Department of Physiology, Graduate School of Medicine, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Takahiko Yokoyama
- Division of Anatomy and Developmental Biology, Department of Anatomy, Graduate School of Medicine, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| |
Collapse
|
45
|
Doerner JF, Delling M, Clapham DE. Ion channels and calcium signaling in motile cilia. eLife 2015; 4. [PMID: 26650848 PMCID: PMC4714969 DOI: 10.7554/elife.11066] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2015] [Accepted: 10/27/2015] [Indexed: 01/15/2023] Open
Abstract
The beating of motile cilia generates fluid flow over epithelia in brain ventricles, airways, and Fallopian tubes. Here, we patch clamp single motile cilia of mammalian ependymal cells and examine their potential function as a calcium signaling compartment. Resting motile cilia calcium concentration ([Ca2+] ~170 nM) is only slightly elevated over cytoplasmic [Ca2+] (~100 nM) at steady state. Ca2+ changes that arise in the cytoplasm rapidly equilibrate in motile cilia. We measured CaV1 voltage-gated calcium channels in ependymal cells, but these channels are not specifically enriched in motile cilia. Membrane depolarization increases ciliary [Ca2+], but only marginally alters cilia beating and cilia-driven fluid velocity within short (~1 min) time frames. We conclude that beating of ependymal motile cilia is not tightly regulated by voltage-gated calcium channels, unlike that of well-studied motile cilia and flagella in protists, such as Paramecia and Chlamydomonas. DOI:http://dx.doi.org/10.7554/eLife.11066.001 Certain specialized cells in the brain, airways and Fallopian tubes have large numbers of hair-like structures called motile cilia on their surface. By beating in a synchronized manner, these cilia help to move fluids across the surface of the cells: for example, cilia on lung cells beat to clear mucus away, while those in the brain help the cerebrospinal fluid to circulate. Motile cilia in mammals are structurally similar to the flagella that propel sperm cells and certain single-celled organisms around their environments. These flagella have specialized pore-forming proteins called ion channels in their membrane through which calcium ions can move. This flow of calcium ions controls the beating of the flagella. However, it is unclear whether a similar movement of calcium ions across the cilia membrane regulates motile cilia beating in mammals. Doerner et al. have now used a method called patch clamping to study the movement of calcium ions across the membrane of the motile cilia found on a particular type of mouse brain cell. This revealed that unlike flagella, these motile cilia have very few voltage-gated calcium channels; instead, the vast majority of these ion channels reside in the main body of the cell. Furthermore, the level of calcium ions in the motile cilia follows changes in calcium ion levels that originate in the cell body. Overall, Doerner et al. demonstrate that the activity of voltage-gated calcium channels does not control the beating rhythm of the motile cilia in the mouse brain or how quickly the fluid above the cell surface moves. Future work should investigate whether this is also the case for the cells that line the trachea and Fallopian tubes. DOI:http://dx.doi.org/10.7554/eLife.11066.002
Collapse
Affiliation(s)
- Julia F Doerner
- Department of Cardiology, Howard Hughes Medical Institute, Boston Children's Hospital, Boston, United States.,Department of Neurobiology, Harvard Medical School, Boston, United States
| | - Markus Delling
- Department of Cardiology, Howard Hughes Medical Institute, Boston Children's Hospital, Boston, United States.,Department of Neurobiology, Harvard Medical School, Boston, United States
| | - David E Clapham
- Department of Cardiology, Howard Hughes Medical Institute, Boston Children's Hospital, Boston, United States.,Department of Neurobiology, Harvard Medical School, Boston, United States
| |
Collapse
|
46
|
Tran PV, Lechtreck KF. An age of enlightenment for cilia: The FASEB summer research conference on the "Biology of Cilia and Flagella". Dev Biol 2015; 409:319-28. [PMID: 26597000 DOI: 10.1016/j.ydbio.2015.10.030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2015] [Accepted: 10/26/2015] [Indexed: 10/22/2022]
Abstract
From July 19-24, 2015, 169 clinicians and basic scientists gathered in the vertiginous heights of Snowmass, Colorado (2502 m) for the fourth FASEB summer research conference on the 'Biology of Cilia and Flagella'. Organizers Maureen Barr (Rutgers University), Iain Drummond (Massachusetts General Hospital/Harvard Medical School), and Jagesh Shah (Brigham and Women's Hospital/Harvard Medical School) assembled a program filled with new data and forward-thinking ideas documenting the ongoing growth of the field. Sixty oral presentations and 77 posters covered novel aspects of cilia structure, ciliogenesis, cilia motility, cilia-mediated signaling, and cilia-related disease. In this report, we summarize the meeting, highlight exciting developments and discuss open questions.
Collapse
Affiliation(s)
- Pamela V Tran
- University of Kansas Medical Center, Kansas City, KS 66160, United States.
| | | |
Collapse
|
47
|
Raghavan V, Weisz OA. Discerning the role of mechanosensors in regulating proximal tubule function. Am J Physiol Renal Physiol 2015; 310:F1-5. [PMID: 26662200 DOI: 10.1152/ajprenal.00373.2015] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
All cells in the body experience external mechanical forces such as shear stress and stretch. These forces are sensed by specialized structures in the cell known as mechanosensors. Cells lining the proximal tubule (PT) of the kidney are continuously exposed to variations in flow rates of the glomerular ultrafiltrate, which manifest as changes in axial shear stress and radial stretch. Studies suggest that these cells respond acutely to variations in flow by modulating their ion transport and endocytic functions to maintain glomerulotubular balance. Conceptually, changes in the axial shear stress in the PT could be sensed by three known structures, namely, the microvilli, the glycocalyx, and primary cilia. The orthogonal component of the force produced by flow exhibits as radial stretch and can cause expansion of the tubule. Forces of stretch are transduced by integrins, by stretch-activated channels, and by cell-cell contacts. This review summarizes our current understanding of flow sensing in PT epithelia, discusses challenges in dissecting the role of individual flow sensors in the mechanosensitive responses, and identifies potential areas of opportunity for new study.
Collapse
Affiliation(s)
- Venkatesan Raghavan
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Ora A Weisz
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| |
Collapse
|
48
|
Mrug M, Zhou J, Yang C, Aronow BJ, Cui X, Schoeb TR, Siegal GP, Yoder BK, Guay-Woodford LM. Genetic and Informatic Analyses Implicate Kif12 as a Candidate Gene within the Mpkd2 Locus That Modulates Renal Cystic Disease Severity in the Cys1cpk Mouse. PLoS One 2015; 10:e0135678. [PMID: 26295839 PMCID: PMC4546649 DOI: 10.1371/journal.pone.0135678] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Accepted: 07/25/2015] [Indexed: 01/02/2023] Open
Abstract
We have previously mapped the interval on Chromosome 4 for a major polycystic kidney disease modifier (Mpkd) of the B6(Cg)-Cys1cpk/J mouse model of recessive polycystic kidney disease (PKD). Informatic analyses predicted that this interval contains at least three individual renal cystic disease severity-modulating loci (Mpkd1-3). In the current study, we provide further validation of these predicted effects using a congenic mouse line carrying the entire CAST/EiJ (CAST)-derived Mpkd1-3 interval on the C57BL/6J background. We have also generated a derivative congenic line with a refined CAST-derived Mpkd1-2 interval and demonstrated its dominantly-acting disease-modulating effects (e.g., 4.2-fold increase in total cyst area; p<0.001). The relative strength of these effects allowed the use of recombinants from these crosses to fine map the Mpkd2 effects to a <14 Mbp interval that contains 92 RefSeq sequences. One of them corresponds to the previously described positional Mpkd2 candidate gene, Kif12. Among the positional Mpkd2 candidates, only expression of Kif12 correlates strongly with the expression pattern of Cys1 across multiple anatomical nephron structures and developmental time points. Also, we demonstrate that Kif12 encodes a primary cilium-associated protein. Together, these data provide genetic and informatic validation of the predicted renal cystic disease-modulating effects of Mpkd1-3 loci and implicate Kif12 as the candidate locus for Mpkd2.
Collapse
Affiliation(s)
- Michal Mrug
- Department of Medicine, The University of Alabama at Birmingham, Birmingham, AL 35294, United States of America
- Department of Veterans Affairs Medical Center, Birmingham, AL 35233, United States of America
- * E-mail: (MM); (LMGW)
| | - Juling Zhou
- Department of Medicine, The University of Alabama at Birmingham, Birmingham, AL 35294, United States of America
| | - Chaozhe Yang
- Department of Genetics, The University of Alabama at Birmingham, Birmingham, AL 35294, United States of America
- Center for Translational Science, Children's National Health System, Washington, DC 20010, United States of America
| | - Bruce J. Aronow
- Division of Biomedical Informatics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 35229, United States of America
| | - Xiangqin Cui
- Department of Biostatistics, The University of Alabama at Birmingham, Birmingham, AL 35294, United States of America
| | - Trenton R. Schoeb
- Department of Genetics, The University of Alabama at Birmingham, Birmingham, AL 35294, United States of America
| | - Gene P. Siegal
- Department of Pathology, The University of Alabama at Birmingham, Birmingham, AL 35294, United States of America
| | - Bradley K Yoder
- Department of Cell, Developmental and Integrative Biology, The University of Alabama at Birmingham, Birmingham, AL 35294, United States of America
| | - Lisa M. Guay-Woodford
- Department of Genetics, The University of Alabama at Birmingham, Birmingham, AL 35294, United States of America
- Center for Translational Science, Children's National Health System, Washington, DC 20010, United States of America
- * E-mail: (MM); (LMGW)
| |
Collapse
|
49
|
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.
Collapse
|
50
|
Wang S, Burton JC, Behringer RR, Larina IV. In vivo micro-scale tomography of ciliary behavior in the mammalian oviduct. Sci Rep 2015; 5:13216. [PMID: 26279472 PMCID: PMC4538602 DOI: 10.1038/srep13216] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 07/21/2015] [Indexed: 11/09/2022] Open
Abstract
Motile cilia in the mammalian oviduct play a key role in reproduction, such as transporting fertilized oocytes to the uterus for implantation. Due to their small size (~5-10 μm in length and ~300 nm in diameter), live visualization of cilia and their activity in the lumen of the oviduct through tissue layers represents a major challenge not yet overcome. Here, we report a functional low-coherence optical imaging technique that allows in vivo depth-resolved mapping of the cilia location and cilia beat frequency (CBF) in the intact mouse oviduct with micro-scale spatial resolution. We validate our approach with widely-used microscopic imaging methods, present the first in vivo mapping of the oviduct CBF in its native context, and demonstrate the ability of this approach to differentiate CBF in different locations of the oviduct at different post-conception stages. This technique opens a range of opportunities for live studies in reproductive medicine as well as other areas focused on cilia activity and related ciliopathies.
Collapse
Affiliation(s)
- Shang Wang
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Jason C Burton
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Richard R Behringer
- Department of Genetics, University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA
| | - Irina V Larina
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX 77030, USA
| |
Collapse
|