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Guichard P, Hamel V, Gönczy P. The Rise of the Cartwheel: Seeding the Centriole Organelle. Bioessays 2018; 40:e1700241. [DOI: 10.1002/bies.201700241] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 01/21/2018] [Indexed: 11/06/2022]
Affiliation(s)
- Paul Guichard
- Department of Cell Biology; University of Geneva Sciences III Geneva; Switzerland
| | - Virginie Hamel
- Department of Cell Biology; University of Geneva Sciences III Geneva; Switzerland
| | - Pierre Gönczy
- School of Life Sciences; Swiss Institute for Experimental Cancer Research (ISREC); Swiss Federal Institute of Technology (EPFL) Lausanne; Switzerland
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Kim YJ, Osborn DP, Lee JY, Araki M, Araki K, Mohun T, Känsäkoski J, Brandstack N, Kim HT, Miralles F, Kim CH, Brown NA, Kim HG, Martinez-Barbera JP, Ataliotis P, Raivio T, Layman LC, Kim SH. WDR11-mediated Hedgehog signalling defects underlie a new ciliopathy related to Kallmann syndrome. EMBO Rep 2018; 19:269-289. [PMID: 29263200 PMCID: PMC5797970 DOI: 10.15252/embr.201744632] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 11/14/2017] [Accepted: 11/17/2017] [Indexed: 12/27/2022] Open
Abstract
WDR11 has been implicated in congenital hypogonadotropic hypogonadism (CHH) and Kallmann syndrome (KS), human developmental genetic disorders defined by delayed puberty and infertility. However, WDR11's role in development is poorly understood. Here, we report that WDR11 modulates the Hedgehog (Hh) signalling pathway and is essential for ciliogenesis. Disruption of WDR11 expression in mouse and zebrafish results in phenotypic characteristics associated with defective Hh signalling, accompanied by dysgenesis of ciliated tissues. Wdr11-null mice also exhibit early-onset obesity. We find that WDR11 shuttles from the cilium to the nucleus in response to Hh signalling. WDR11 regulates the proteolytic processing of GLI3 and cooperates with the transcription factor EMX1 in the induction of downstream Hh pathway gene expression and gonadotrophin-releasing hormone production. The CHH/KS-associated human mutations result in loss of function of WDR11. Treatment with the Hh agonist purmorphamine partially rescues the WDR11 haploinsufficiency phenotypes. Our study reveals a novel class of ciliopathy caused by WDR11 mutations and suggests that CHH/KS may be a part of the human ciliopathy spectrum.
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Affiliation(s)
- Yeon-Joo Kim
- Molecular and Clinical Sciences Research Institute, St. George's, University of London, London, UK
| | - Daniel Ps Osborn
- Molecular and Clinical Sciences Research Institute, St. George's, University of London, London, UK
| | - Ji-Young Lee
- Molecular and Clinical Sciences Research Institute, St. George's, University of London, London, UK
| | - Masatake Araki
- Institute of Resource Development and Analysis, Kumamoto University, Kumamoto, Japan
| | - Kimi Araki
- Institute of Resource Development and Analysis, Kumamoto University, Kumamoto, Japan
| | | | | | | | - Hyun-Taek Kim
- Department of Biology, Chungnam National University, Daejeon, Korea
| | - Francesc Miralles
- Molecular and Clinical Sciences Research Institute, St. George's, University of London, London, UK
| | - Cheol-Hee Kim
- Department of Biology, Chungnam National University, Daejeon, Korea
| | - Nigel A Brown
- Molecular and Clinical Sciences Research Institute, St. George's, University of London, London, UK
| | - Hyung-Goo Kim
- Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Juan Pedro Martinez-Barbera
- Developmental Biology and Cancer Programme, Birth Defects Research Centre, UCL Great Ormond Street Institute of Child Health, London, UK
| | - Paris Ataliotis
- Molecular and Clinical Sciences Research Institute, St. George's, University of London, London, UK
| | - Taneli Raivio
- Helsinki University Central Hospital, Helsinki, Finland
| | | | - Soo-Hyun Kim
- Molecular and Clinical Sciences Research Institute, St. George's, University of London, London, UK
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Jin X, Chen L, Wang D, Zhang Y, Chen Z, Huang H. Novel compound heterozygous mutation in the POC1B gene underlie peripheral cone dystrophy in a Chinese family. Ophthalmic Genet 2018; 39:300-306. [PMID: 29377742 DOI: 10.1080/13816810.2018.1430239] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
PURPOSE To describe the clinical characteristics of a Chinese family with peripheral cone dystrophy (PCD) and identify the gene mutations causing PCD. METHODS The Chinese PCD pedigree underwent comprehensive ophthalmic examinations, including visual acuity, slit lamp examination, fundoscopy, visual field examination, autofluorescence, fluorescence fundus angiography and indocyanine green angiography, full-field electroretinograms, and spectral-domain optical coherence tomography. The targeted next-generation sequencing of COD or cone-rod dystrophy (CORD) genes was used to identify the causative mutation. RESULT The fundus characteristics of the Chinese patient were consistent with PCD. The novel compound heterozygous mutation, c.1354C>T and c.710A>G, in POC1B was identified in the patient, the mutations were segregated with the PCD phenotype in the family and were absent from ethnically matched control chromosomes. Prediction analysis demonstrated the novel missense mutation, POC1B c.710A>G, might be damaging. CONCLUSIONS PCD was a type of COD or CORD and the novel compound heterozygous mutation in POC1B was responsible for PCD phenotype in the family.
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Affiliation(s)
- Xin Jin
- a Department of Ophthalmology , Hainan Branch of Chinese PLA General Hospital , Sanya , Hainan Province , China.,b Department of Ophthalmology , Chinese PLA General Hospital , Beijing , China
| | - Lanlan Chen
- a Department of Ophthalmology , Hainan Branch of Chinese PLA General Hospital , Sanya , Hainan Province , China
| | - Dajiang Wang
- b Department of Ophthalmology , Chinese PLA General Hospital , Beijing , China
| | - Yixin Zhang
- a Department of Ophthalmology , Hainan Branch of Chinese PLA General Hospital , Sanya , Hainan Province , China
| | - Zehua Chen
- a Department of Ophthalmology , Hainan Branch of Chinese PLA General Hospital , Sanya , Hainan Province , China
| | - Houbin Huang
- a Department of Ophthalmology , Hainan Branch of Chinese PLA General Hospital , Sanya , Hainan Province , China.,b Department of Ophthalmology , Chinese PLA General Hospital , Beijing , China
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54
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Werner S, Pimenta-Marques A, Bettencourt-Dias M. Maintaining centrosomes and cilia. J Cell Sci 2017; 130:3789-3800. [DOI: 10.1242/jcs.203505] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
ABSTRACT
Centrosomes and cilia are present in organisms from all branches of the eukaryotic tree of life. These structures are composed of microtubules and various other proteins, and are required for a plethora of cell processes such as structuring the cytoskeleton, sensing the environment, and motility. Deregulation of centrosome and cilium components leads to a wide range of diseases, some of which are incompatible with life. Centrosomes and cilia are thought to be very stable and can persist over long periods of time. However, these structures can disappear in certain developmental stages and diseases. Moreover, some centrosome and cilia components are quite dynamic. While a large body of knowledge has been produced regarding the biogenesis of these structures, little is known about how they are maintained. In this Review, we propose the existence of specific centrosome and cilia maintenance programs, which are regulated during development and homeostasis, and when deregulated can lead to disease.
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Affiliation(s)
- Sascha Werner
- Cell Cycle Regulation Lab, Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - Ana Pimenta-Marques
- Cell Cycle Regulation Lab, Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - Mónica Bettencourt-Dias
- Cell Cycle Regulation Lab, Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
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55
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Castro-Sánchez S, Álvarez-Satta M, Tohamy MA, Beltran S, Derdak S, Valverde D. Whole exome sequencing as a diagnostic tool for patients with ciliopathy-like phenotypes. PLoS One 2017; 12:e0183081. [PMID: 28800606 PMCID: PMC5553726 DOI: 10.1371/journal.pone.0183081] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 07/29/2017] [Indexed: 12/13/2022] Open
Abstract
Ciliopathies are a group of rare disorders characterized by a high genetic and phenotypic variability, which complicates their molecular diagnosis. Hence the need to use the latest powerful approaches to faster identify the genetic defect in these patients. We applied whole exome sequencing to six consanguineous families clinically diagnosed with ciliopathy-like disease, and for which mutations in predominant Bardet-Biedl syndrome (BBS) genes had previously been excluded. Our strategy, based on first applying several filters to ciliary variants and using many of the bioinformatics tools available, allowed us to identify causal mutations in BBS2, ALMS1 and CRB1 genes in four families, thus confirming the molecular diagnosis of ciliopathy. In the remaining two families, after first rejecting the presence of pathogenic variants in common cilia-related genes, we adopted a new filtering strategy combined with prioritisation tools to rank the final candidate genes for each case. Thus, we propose CORO2B, LMO7 and ZNF17 as novel candidate ciliary genes, but further functional studies will be needed to confirm their role. Our data show the usefulness of this strategy to diagnose patients with unclear phenotypes, and therefore the success of applying such technologies to achieve a rapid and reliable molecular diagnosis, improving genetic counselling for these patients. In addition, the described pipeline also highlights the common pitfalls associated to the large volume of data we have to face and the difficulty of assigning a functional role to these changes, hence the importance of designing the most appropriate strategy according to each case.
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Affiliation(s)
- Sheila Castro-Sánchez
- Departamento de Bioquímica, Genética e Inmunología, Facultad de Biología, Universidad de Vigo, Vigo, Spain
- Research Group of Rare Diseases & Pediatric Medicine, Instituto de Investigación Sanitaria Galicia Sur (IISGS), SERGAS-UVIGO, Hospital Álvaro Cunqueiro, Vigo, Spain
- Centro de Investigaciones Biomédicas (CINBIO) (Centro Singular de Investigación de Galicia), Universidad de Vigo, Vigo, Spain
| | - María Álvarez-Satta
- Departamento de Bioquímica, Genética e Inmunología, Facultad de Biología, Universidad de Vigo, Vigo, Spain
- Research Group of Rare Diseases & Pediatric Medicine, Instituto de Investigación Sanitaria Galicia Sur (IISGS), SERGAS-UVIGO, Hospital Álvaro Cunqueiro, Vigo, Spain
- Centro de Investigaciones Biomédicas (CINBIO) (Centro Singular de Investigación de Galicia), Universidad de Vigo, Vigo, Spain
| | - Mohamed A. Tohamy
- Departamento de Bioquímica, Genética e Inmunología, Facultad de Biología, Universidad de Vigo, Vigo, Spain
| | - Sergi Beltran
- CNAG-CRG, Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Sophia Derdak
- CNAG-CRG, Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Diana Valverde
- Departamento de Bioquímica, Genética e Inmunología, Facultad de Biología, Universidad de Vigo, Vigo, Spain
- Research Group of Rare Diseases & Pediatric Medicine, Instituto de Investigación Sanitaria Galicia Sur (IISGS), SERGAS-UVIGO, Hospital Álvaro Cunqueiro, Vigo, Spain
- Centro de Investigaciones Biomédicas (CINBIO) (Centro Singular de Investigación de Galicia), Universidad de Vigo, Vigo, Spain
- * E-mail:
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Tetrahymena as a Unicellular Model Eukaryote: Genetic and Genomic Tools. Genetics 2017; 203:649-65. [PMID: 27270699 DOI: 10.1534/genetics.114.169748] [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: 03/01/2016] [Accepted: 04/08/2016] [Indexed: 12/12/2022] Open
Abstract
Tetrahymena thermophila is a ciliate model organism whose study has led to important discoveries and insights into both conserved and divergent biological processes. In this review, we describe the tools for the use of Tetrahymena as a model eukaryote, including an overview of its life cycle, orientation to its evolutionary roots, and methodological approaches to forward and reverse genetics. Recent genomic tools have expanded Tetrahymena's utility as a genetic model system. With the unique advantages that Tetrahymena provide, we argue that it will continue to be a model organism of choice.
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Broadgate S, Yu J, Downes SM, Halford S. Unravelling the genetics of inherited retinal dystrophies: Past, present and future. Prog Retin Eye Res 2017; 59:53-96. [PMID: 28363849 DOI: 10.1016/j.preteyeres.2017.03.003] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 03/21/2017] [Accepted: 03/23/2017] [Indexed: 02/07/2023]
Abstract
The identification of the genes underlying monogenic diseases has been of interest to clinicians and scientists for many years. Using inherited retinal dystrophies as an example of monogenic disease we describe the history of molecular genetic techniques that have been pivotal in the discovery of disease causing genes. The methods that were developed in the 1970's and 80's are still in use today but have been refined and improved. These techniques enabled the concept of the Human Genome Project to be envisaged and ultimately realised. When the successful conclusion of the project was announced in 2003 many new tools and, as importantly, many collaborations had been developed that facilitated a rapid identification of disease genes. In the post-human genome project era advances in computing power and the clever use of the properties of DNA replication has allowed the development of next-generation sequencing technologies. These methods have revolutionised the identification of disease genes because for the first time there is no need to define the position of the gene in the genome. The use of next generation sequencing in a diagnostic setting has allowed many more patients with an inherited retinal dystrophy to obtain a molecular diagnosis for their disease. The identification of novel genes that have a role in the development or maintenance of retinal function is opening up avenues of research which will lead to the development of new pharmacological and gene therapy approaches. Neither of which can be used unless the defective gene and protein is known. The continued development of sequencing technologies also holds great promise for the advent of truly personalised medicine.
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Affiliation(s)
- Suzanne Broadgate
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, University of Oxford, Levels 5 and 6 West Wing, John Radcliffe Hospital, Headley Way, Oxford, OX3 9DU, UK
| | - Jing Yu
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, University of Oxford, Levels 5 and 6 West Wing, John Radcliffe Hospital, Headley Way, Oxford, OX3 9DU, UK
| | - Susan M Downes
- Oxford Eye Hospital, Oxford University Hospitals NHS Trust, Oxford, OX3 9DU, UK
| | - Stephanie Halford
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, University of Oxford, Levels 5 and 6 West Wing, John Radcliffe Hospital, Headley Way, Oxford, OX3 9DU, UK.
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58
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Sfr1, a Tetrahymena thermophila Sfi1 Repeat Protein, Modulates the Production of Cortical Row Basal Bodies. mSphere 2016; 1:mSphere00257-16. [PMID: 27904881 PMCID: PMC5112337 DOI: 10.1128/msphere.00257-16] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Accepted: 10/14/2016] [Indexed: 01/08/2023] Open
Abstract
Basal bodies and centrioles are structurally similar and, when rendered dysfunctional as a result of improper assembly or maintenance, are associated with human diseases. Centrins are conserved and abundant components of both structures whose basal body and centriolar functions remain incompletely understood. Despite the extensive study of centrins in Tetrahymena thermophila, little is known about how centrin-binding proteins contribute to centrin’s roles in basal body assembly, stability, and orientation. The sole previous study of the large centrin-binding protein family in Tetrahymena revealed a role for Sfr13 in the stabilization and separation of basal bodies. In this study, we found that Sfr1 localizes to all Tetrahymena basal bodies and complete genetic deletion of SFR1 leads to overproduction of basal bodies. The uncovered inhibitory role of Sfr1 in basal body production suggests that centrin-binding proteins, as well as centrins, may influence basal body number both positively and negatively. Basal bodies are essential microtubule-based structures that template, anchor, and orient cilia at the cell surface. Cilia act primarily in the generation of directional fluid flow and sensory reception, both of which are utilized for a broad spectrum of cellular processes. Although basal bodies contribute to vital cell functions, the molecular contributors of their assembly and maintenance are poorly understood. Previous studies of the ciliate Tetrahymena thermophila revealed important roles for two centrin family members in basal body assembly, separation of new basal bodies, and stability. Here, we characterize the basal body function of a centrin-binding protein, Sfr1, in Tetrahymena. Sfr1 is part of a large family of 13 proteins in Tetrahymena that contain Sfi1 repeats (SFRs), a motif originally identified in Saccharomyces cerevisiae Sfi1 that binds centrin. Sfr1 is the only SFR protein in Tetrahymena that localizes to all cortical row and oral apparatus basal bodies. In addition, Sfr1 resides predominantly at the microtubule scaffold from the proximal cartwheel to the distal transition zone. Complete genomic knockout of SFR1 (sfr1Δ) causes a significant increase in both cortical row basal body density and the number of cortical rows, contributing to an overall overproduction of basal bodies. Reintroduction of Sfr1 into sfr1Δ mutant cells leads to a marked reduction of cortical row basal body density and the total number of cortical row basal bodies. Therefore, Sfr1 directly modulates cortical row basal body production. This study reveals an inhibitory role for Sfr1, and potentially centrins, in Tetrahymena basal body production. IMPORTANCE Basal bodies and centrioles are structurally similar and, when rendered dysfunctional as a result of improper assembly or maintenance, are associated with human diseases. Centrins are conserved and abundant components of both structures whose basal body and centriolar functions remain incompletely understood. Despite the extensive study of centrins in Tetrahymena thermophila, little is known about how centrin-binding proteins contribute to centrin’s roles in basal body assembly, stability, and orientation. The sole previous study of the large centrin-binding protein family in Tetrahymena revealed a role for Sfr13 in the stabilization and separation of basal bodies. In this study, we found that Sfr1 localizes to all Tetrahymena basal bodies and complete genetic deletion of SFR1 leads to overproduction of basal bodies. The uncovered inhibitory role of Sfr1 in basal body production suggests that centrin-binding proteins, as well as centrins, may influence basal body number both positively and negatively.
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59
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Bayless BA, Galati DF, Junker AD, Backer CB, Gaertig J, Pearson CG. Asymmetrically localized proteins stabilize basal bodies against ciliary beating forces. J Cell Biol 2016; 215:457-466. [PMID: 27807131 PMCID: PMC5119938 DOI: 10.1083/jcb.201604135] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Revised: 08/24/2016] [Accepted: 10/04/2016] [Indexed: 11/26/2022] Open
Abstract
Basal bodies (BBs) organize and anchor motile cilia. This study uncovers components that asymmetrically localize to the rotationally symmetric BBs, where they fortify specific BB domains. Asymmetrically localized BB components are necessary to resist asymmetric ciliary forces. Basal bodies are radially symmetric, microtubule-rich structures that nucleate and anchor motile cilia. Ciliary beating produces asymmetric mechanical forces that are resisted by basal bodies. To resist these forces, distinct regions within the basal body ultrastructure and the microtubules themselves must be stable. However, the molecular components that stabilize basal bodies remain poorly defined. Here, we determine that Fop1 functionally interacts with the established basal body stability components Bld10 and Poc1. We find that Fop1 and microtubule glutamylation incorporate into basal bodies at distinct stages of assembly, culminating in their asymmetric enrichment at specific triplet microtubule regions that are predicted to experience the greatest mechanical force from ciliary beating. Both Fop1 and microtubule glutamylation are required to stabilize basal bodies against ciliary beating forces. Our studies reveal that microtubule glutamylation and Bld10, Poc1, and Fop1 stabilize basal bodies against the forces produced by ciliary beating via distinct yet interdependent mechanisms.
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Affiliation(s)
- Brian A Bayless
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, CO 80045
| | - Domenico F Galati
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, CO 80045
| | - Anthony D Junker
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, CO 80045
| | - Chelsea B Backer
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142.,Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142
| | - Jacek Gaertig
- Department of Cellular Biology, University of Georgia, Athens, GA 30602
| | - Chad G Pearson
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, CO 80045
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Khire A, Jo KH, Kong D, Akhshi T, Blachon S, Cekic AR, Hynek S, Ha A, Loncarek J, Mennella V, Avidor-Reiss T. Centriole Remodeling during Spermiogenesis in Drosophila. Curr Biol 2016; 26:3183-3189. [PMID: 28094036 DOI: 10.1016/j.cub.2016.07.006] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Revised: 06/17/2016] [Accepted: 07/06/2016] [Indexed: 10/20/2022]
Abstract
The first cell of an animal (zygote) requires centrosomes that are assembled from paternally inherited centrioles and maternally inherited pericentriolar material (PCM) [1]. In some animals, sperm centrioles with typical ultrastructure are the origin of the first centrosomes in the zygote [2-4]. In other animals, however, sperm centrioles lose their proteins and are thought to be degenerated and non-functional during spermiogenesis [5, 6]. Here, we show that the two sperm centrioles (the giant centriole [GC] and the proximal centriole-like structure [PCL]) in Drosophila melanogaster are remodeled during spermiogenesis through protein enrichment and ultrastructure modification in parallel to previously described centrosomal reduction [7]. We found that the ultrastructure of the matured sperm (spermatozoa) centrioles is modified dramatically and that the PCL does not resemble a typical centriole. We also describe a new phenomenon of Poc1 enrichment of the atypical centrioles in the spermatozoa. Using various mutants, protein expression during spermiogenesis, and RNAi knockdown of paternal Poc1, we found that paternal Poc1 enrichment is essential for the formation of centrioles during spermiogenesis and for the formation of centrosomes after fertilization in the zygote. Altogether, these findings demonstrate that the sperm centrioles are remodeled both in their protein composition and in ultrastructure, yet they are functional and are essential for normal embryogenesis in Drosophila.
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Affiliation(s)
- Atul Khire
- Department of Biological Sciences, University of Toledo, 3050 W. Towerview Boulevard, Toledo, OH 43606, USA
| | - Kyoung H Jo
- Department of Biological Sciences, University of Toledo, 3050 W. Towerview Boulevard, Toledo, OH 43606, USA
| | - Dong Kong
- Laboratory of Protein Dynamics and Signaling, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702-1201, USA
| | - Tara Akhshi
- Department of Biochemistry, Cell Biology Program, The Hospital for Sick Children, University of Toronto, 555 University Avenue, Toronto, ON M5G 1X8, Canada
| | | | - Anthony R Cekic
- Department of Biological Sciences, University of Toledo, 3050 W. Towerview Boulevard, Toledo, OH 43606, USA
| | - Sarah Hynek
- Department of Biological Sciences, University of Toledo, 3050 W. Towerview Boulevard, Toledo, OH 43606, USA
| | - Andrew Ha
- Department of Biological Sciences, University of Toledo, 3050 W. Towerview Boulevard, Toledo, OH 43606, USA
| | - Jadranka Loncarek
- Laboratory of Protein Dynamics and Signaling, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702-1201, USA
| | - Vito Mennella
- Department of Biochemistry, Cell Biology Program, The Hospital for Sick Children, University of Toronto, 555 University Avenue, Toronto, ON M5G 1X8, Canada
| | - Tomer Avidor-Reiss
- Department of Biological Sciences, University of Toledo, 3050 W. Towerview Boulevard, Toledo, OH 43606, USA.
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Meehl JB, Bayless BA, Giddings TH, Pearson CG, Winey M. Tetrahymena Poc1 ensures proper intertriplet microtubule linkages to maintain basal body integrity. Mol Biol Cell 2016; 27:2394-403. [PMID: 27251062 PMCID: PMC4966981 DOI: 10.1091/mbc.e16-03-0165] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 05/27/2016] [Indexed: 12/31/2022] Open
Abstract
Basal bodies comprise nine symmetric triplet microtubules that anchor forces produced by the asymmetric beat pattern of motile cilia. The ciliopathy protein Poc1 stabilizes basal bodies through an unknown mechanism. In poc1∆ cells, electron tomography reveals subtle defects in the organization of intertriplet linkers (A-C linkers) that connect adjacent triplet microtubules. Complete triplet microtubules are lost preferentially near the posterior face of the basal body. Basal bodies that are missing triplets likely remain competent to assemble new basal bodies with nine triplet microtubules, suggesting that the mother basal body microtubule structure does not template the daughter. Our data indicate that Poc1 stabilizes basal body triplet microtubules through linkers between neighboring triplets. Without this stabilization, specific triplet microtubules within the basal body are more susceptible to loss, probably due to force distribution within the basal body during ciliary beating. This work provides insights into how the ciliopathy protein Poc1 maintains basal body integrity.
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Affiliation(s)
- Janet B Meehl
- Molecular, Cellular and Developmental Biology, University of Colorado at Boulder, Boulder, CO 80309
| | - Brian A Bayless
- Department of Cell and Developmental Biology, University of Colorado-Anschutz Medical Campus, Aurora, CO 80045
| | - Thomas H Giddings
- Molecular, Cellular and Developmental Biology, University of Colorado at Boulder, Boulder, CO 80309
| | - Chad G Pearson
- Department of Cell and Developmental Biology, University of Colorado-Anschutz Medical Campus, Aurora, CO 80045
| | - Mark Winey
- Molecular, Cellular and Developmental Biology, University of Colorado at Boulder, Boulder, CO 80309
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Marshall RA, Osborn DPS. Zebrafish: a vertebrate tool for studying basal body biogenesis, structure, and function. Cilia 2016; 5:16. [PMID: 27168933 PMCID: PMC4862167 DOI: 10.1186/s13630-016-0036-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 03/01/2016] [Indexed: 02/27/2023] Open
Abstract
Understanding the role of basal bodies (BBs) during development and disease has been largely overshadowed by research into the function of the cilium. Although these two organelles are closely associated, they have specific roles to complete for successful cellular development. Appropriate development and function of the BB are fundamental for cilia function. Indeed, there are a growing number of human genetic diseases affecting ciliary development, known collectively as the ciliopathies. Accumulating evidence suggests that BBs establish cell polarity, direct ciliogenesis, and provide docking sites for proteins required within the ciliary axoneme. Major contributions to our knowledge of BB structure and function have been provided by studies in flagellated or ciliated unicellular eukaryotic organisms, specifically Tetrahymena and Chlamydomonas. Reproducing these and other findings in vertebrates has required animal in vivo models. Zebrafish have fast become one of the primary organisms of choice for modeling vertebrate functional genetics. Rapid ex-utero development, proficient egg laying, ease of genetic manipulation, and affordability make zebrafish an attractive vertebrate research tool. Furthermore, zebrafish share over 80 % of disease causing genes with humans. In this article, we discuss the merits of using zebrafish to study BB functional genetics, review current knowledge of zebrafish BB ultrastructure and mechanisms of function, and consider the outlook for future zebrafish-based BB studies.
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Affiliation(s)
- Ryan A Marshall
- Cell Sciences and Genetics Research Centre, St George's University of London, London, SW17 0RE UK
| | - Daniel P S Osborn
- Cell Sciences and Genetics Research Centre, St George's University of London, London, SW17 0RE UK
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63
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SOFT syndrome caused by compound heterozygous mutations of POC1A and its skeletal manifestation. J Hum Genet 2016; 61:561-4. [DOI: 10.1038/jhg.2015.174] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 12/23/2015] [Accepted: 12/24/2015] [Indexed: 01/12/2023]
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Abstract
Tetrahymena thermophila is a ciliate with hundreds of cilia primarily used for cellular motility. These cells propel themselves by generating hydrodynamic forces through coordinated ciliary beating. The coordination of cilia is ensured by the polarized organization of basal bodies (BBs), which exhibit remarkable structural and molecular conservation with BBs in other eukaryotes. During each cell cycle, massive BB assembly occurs and guarantees that future Tetrahymena cells gain a full complement of BBs and their associated cilia. BB duplication occurs next to existing BBs, and the predictable patterning of new BBs is facilitated by asymmetric BB accessory structures that are integrated with a membrane-associated cytoskeletal network. The large number of BBs combined with robust molecular genetics merits Tetrahymena as a unique model system to elucidate the fundamental events of BB assembly and organization.
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Affiliation(s)
- Brian A Bayless
- Department of Cell and Developmental Biology, University of Colorado-Anschutz Medical Campus, 2801 E. 17th Ave, Aurora, CO 80045-2537 USA
| | - Domenico F Galati
- Department of Cell and Developmental Biology, University of Colorado-Anschutz Medical Campus, 2801 E. 17th Ave, Aurora, CO 80045-2537 USA
| | - Chad G Pearson
- Department of Cell and Developmental Biology, University of Colorado-Anschutz Medical Campus, 2801 E. 17th Ave, Aurora, CO 80045-2537 USA
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Galati DF, Abuin DS, Tauber GA, Pham AT, Pearson CG. Automated image analysis reveals the dynamic 3-dimensional organization of multi-ciliary arrays. Biol Open 2015; 5:20-31. [PMID: 26700722 PMCID: PMC4728305 DOI: 10.1242/bio.014951] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Multi-ciliated cells (MCCs) use polarized fields of undulating cilia (ciliary array) to produce fluid flow that is essential for many biological processes. Cilia are positioned by microtubule scaffolds called basal bodies (BBs) that are arranged within a spatially complex 3-dimensional geometry (3D). Here, we develop a robust and automated computational image analysis routine to quantify 3D BB organization in the ciliate, Tetrahymena thermophila. Using this routine, we generate the first morphologically constrained 3D reconstructions of Tetrahymena cells and elucidate rules that govern the kinetics of MCC organization. We demonstrate the interplay between BB duplication and cell size expansion through the cell cycle. In mutant cells, we identify a potential BB surveillance mechanism that balances large gaps in BB spacing by increasing the frequency of closely spaced BBs in other regions of the cell. Finally, by taking advantage of a mutant predisposed to BB disorganization, we locate the spatial domains that are most prone to disorganization by environmental stimuli. Collectively, our analyses reveal the importance of quantitative image analysis to understand the principles that guide the 3D organization of MCCs. Summary: We develop an automated computational image analysis routine to quantify basal body organization, which detects subtle spatial phenotypes resulting from environmental and genetic perturbations.
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Affiliation(s)
- Domenico F Galati
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, 2801 East 17th Ave, Aurora, CO 80045-2537, USA
| | - David S Abuin
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, 2801 East 17th Ave, Aurora, CO 80045-2537, USA
| | - Gabriel A Tauber
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, 2801 East 17th Ave, Aurora, CO 80045-2537, USA
| | - Andrew T Pham
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, 2801 East 17th Ave, Aurora, CO 80045-2537, USA
| | - Chad G Pearson
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, 2801 East 17th Ave, Aurora, CO 80045-2537, USA
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Geister KA, Brinkmeier ML, Cheung LY, Wendt J, Oatley MJ, Burgess DL, Kozloff KM, Cavalcoli JD, Oatley JM, Camper SA. LINE-1 Mediated Insertion into Poc1a (Protein of Centriole 1 A) Causes Growth Insufficiency and Male Infertility in Mice. PLoS Genet 2015; 11:e1005569. [PMID: 26496357 PMCID: PMC4619696 DOI: 10.1371/journal.pgen.1005569] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Accepted: 09/15/2015] [Indexed: 11/19/2022] Open
Abstract
Skeletal dysplasias are a common, genetically heterogeneous cause of short stature that can result from disruptions in many cellular processes. We report the identification of the lesion responsible for skeletal dysplasia and male infertility in the spontaneous, recessive mouse mutant chagun. We determined that Poc1a, encoding protein of the centriole 1a, is disrupted by the insertion of a processed Cenpw cDNA, which is flanked by target site duplications, suggestive of a LINE-1 retrotransposon-mediated event. Mutant fibroblasts have impaired cilia formation and multipolar spindles. Male infertility is caused by defective spermatogenesis early in meiosis and progressive germ cell loss. Spermatogonial stem cell transplantation studies revealed that Poc1a is essential for normal function of both Sertoli cells and germ cells. The proliferative zone of the growth plate is small and disorganized because chondrocytes fail to re-align after cell division and undergo increased apoptosis. Poc1a and several other genes associated with centrosome function can affect the skeleton and lead to skeletal dysplasias and primordial dwarfisms. This mouse mutant reveals how centrosome dysfunction contributes to defects in skeletal growth and male infertility.
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Affiliation(s)
- Krista A. Geister
- Graduate Program in Cellular and Molecular Biology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Michelle L. Brinkmeier
- Department of Human Genetics, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Leonard Y. Cheung
- Department of Human Genetics, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Jennifer Wendt
- Roche NimbleGen, Inc., Research and Development, Madison, Wisconsin, United States of America
| | - Melissa J. Oatley
- School of Molecular Biosciences and Center for Reproductive Biology, Washington State University, Pullman, Washington, United States of America
| | - Daniel L. Burgess
- Roche NimbleGen, Inc., Research and Development, Madison, Wisconsin, United States of America
| | - Kenneth M. Kozloff
- Department of Orthopedic Surgery, University of Michigan, Ann Arbor, Michigan, United States of America
| | - James D. Cavalcoli
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Jon M. Oatley
- School of Molecular Biosciences and Center for Reproductive Biology, Washington State University, Pullman, Washington, United States of America
| | - Sally A. Camper
- Graduate Program in Cellular and Molecular Biology, University of Michigan, Ann Arbor, Michigan, United States of America
- Department of Human Genetics, University of Michigan, Ann Arbor, Michigan, United States of America
- * E-mail:
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67
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Chen JH, Segni M, Payne F, Huang-Doran I, Sleigh A, Adams C, Savage DB, O'Rahilly S, Semple RK, Barroso I. Truncation of POC1A associated with short stature and extreme insulin resistance. J Mol Endocrinol 2015; 55:147-58. [PMID: 26336158 PMCID: PMC4722288 DOI: 10.1530/jme-15-0090] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
We describe a female proband with primordial dwarfism, skeletal dysplasia, facial dysmorphism, extreme dyslipidaemic insulin resistance and fatty liver associated with a novel homozygous frameshift mutation in POC1A, predicted to affect two of the three protein products of the gene. POC1A encodes a protein associated with centrioles throughout the cell cycle and implicated in both mitotic spindle and primary ciliary function. Three homozygous mutations affecting all isoforms of POC1A have recently been implicated in a similar syndrome of primordial dwarfism, although no detailed metabolic phenotypes were described. Primary cells from the proband we describe exhibited increased centrosome amplification and multipolar spindle formation during mitosis, but showed normal DNA content, arguing against mitotic skipping, cleavage failure or cell fusion. Despite evidence of increased DNA damage in cells with supernumerary centrosomes, no aneuploidy was detected. Extensive centrosome clustering both at mitotic spindles and in primary cilia mitigated the consequences of centrosome amplification, and primary ciliary formation was normal. Although further metabolic studies of patients with POC1A mutations are warranted, we suggest that POC1A may be added to ALMS1 and PCNT as examples of centrosomal or pericentriolar proteins whose dysfunction leads to extreme dyslipidaemic insulin resistance. Further investigation of links between these molecular defects and adipose tissue dysfunction is likely to yield insights into mechanisms of adipose tissue maintenance and regeneration that are critical to metabolic health.
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Affiliation(s)
- Jian-Hua Chen
- The University of Cambridge Metabolic Research Laboratories Wellcome Trust-MRC Institute of Metabolic Science, Cambridge, UK The National Institute for Health Research Cambridge Biomedical Research Centre Cambridge, UK Department of Pediatrics Sapienza University, Rome, Italy Metabolic Disease Group Wellcome Trust Sanger Institute, Cambridge, UK Wolfson Brain Imaging Centre University of Cambridge, Cambridge, UK National Institute for Health Research/Wellcome Trust Clinical Research Facility Cambridge, UK The University of Cambridge Metabolic Research Laboratories Wellcome Trust-MRC Institute of Metabolic Science, Cambridge, UK The National Institute for Health Research Cambridge Biomedical Research Centre Cambridge, UK Department of Pediatrics Sapienza University, Rome, Italy Metabolic Disease Group Wellcome Trust Sanger Institute, Cambridge, UK Wolfson Brain Imaging Centre University of Cambridge, Cambridge, UK National Institute for Health Research/Wellcome Trust Clinical Research Facility Cambridge, UK
| | - Maria Segni
- The University of Cambridge Metabolic Research Laboratories Wellcome Trust-MRC Institute of Metabolic Science, Cambridge, UK The National Institute for Health Research Cambridge Biomedical Research Centre Cambridge, UK Department of Pediatrics Sapienza University, Rome, Italy Metabolic Disease Group Wellcome Trust Sanger Institute, Cambridge, UK Wolfson Brain Imaging Centre University of Cambridge, Cambridge, UK National Institute for Health Research/Wellcome Trust Clinical Research Facility Cambridge, UK
| | - Felicity Payne
- The University of Cambridge Metabolic Research Laboratories Wellcome Trust-MRC Institute of Metabolic Science, Cambridge, UK The National Institute for Health Research Cambridge Biomedical Research Centre Cambridge, UK Department of Pediatrics Sapienza University, Rome, Italy Metabolic Disease Group Wellcome Trust Sanger Institute, Cambridge, UK Wolfson Brain Imaging Centre University of Cambridge, Cambridge, UK National Institute for Health Research/Wellcome Trust Clinical Research Facility Cambridge, UK
| | - Isabel Huang-Doran
- The University of Cambridge Metabolic Research Laboratories Wellcome Trust-MRC Institute of Metabolic Science, Cambridge, UK The National Institute for Health Research Cambridge Biomedical Research Centre Cambridge, UK Department of Pediatrics Sapienza University, Rome, Italy Metabolic Disease Group Wellcome Trust Sanger Institute, Cambridge, UK Wolfson Brain Imaging Centre University of Cambridge, Cambridge, UK National Institute for Health Research/Wellcome Trust Clinical Research Facility Cambridge, UK The University of Cambridge Metabolic Research Laboratories Wellcome Trust-MRC Institute of Metabolic Science, Cambridge, UK The National Institute for Health Research Cambridge Biomedical Research Centre Cambridge, UK Department of Pediatrics Sapienza University, Rome, Italy Metabolic Disease Group Wellcome Trust Sanger Institute, Cambridge, UK Wolfson Brain Imaging Centre University of Cambridge, Cambridge, UK National Institute for Health Research/Wellcome Trust Clinical Research Facility Cambridge, UK
| | - Alison Sleigh
- The University of Cambridge Metabolic Research Laboratories Wellcome Trust-MRC Institute of Metabolic Science, Cambridge, UK The National Institute for Health Research Cambridge Biomedical Research Centre Cambridge, UK Department of Pediatrics Sapienza University, Rome, Italy Metabolic Disease Group Wellcome Trust Sanger Institute, Cambridge, UK Wolfson Brain Imaging Centre University of Cambridge, Cambridge, UK National Institute for Health Research/Wellcome Trust Clinical Research Facility Cambridge, UK The University of Cambridge Metabolic Research Laboratories Wellcome Trust-MRC Institute of Metabolic Science, Cambridge, UK The National Institute for Health Research Cambridge Biomedical Research Centre Cambridge, UK Department of Pediatrics Sapienza University, Rome, Italy Metabolic Disease Group Wellcome Trust Sanger Institute, Cambridge, UK Wolfson Brain Imaging Centre University of Cambridge, Cambridge, UK National Institute for Health Research/Wellcome Trust Clinical Research Facility Cambridge, UK
| | - Claire Adams
- The University of Cambridge Metabolic Research Laboratories Wellcome Trust-MRC Institute of Metabolic Science, Cambridge, UK The National Institute for Health Research Cambridge Biomedical Research Centre Cambridge, UK Department of Pediatrics Sapienza University, Rome, Italy Metabolic Disease Group Wellcome Trust Sanger Institute, Cambridge, UK Wolfson Brain Imaging Centre University of Cambridge, Cambridge, UK National Institute for Health Research/Wellcome Trust Clinical Research Facility Cambridge, UK The University of Cambridge Metabolic Research Laboratories Wellcome Trust-MRC Institute of Metabolic Science, Cambridge, UK The National Institute for Health Research Cambridge Biomedical Research Centre Cambridge, UK Department of Pediatrics Sapienza University, Rome, Italy Metabolic Disease Group Wellcome Trust Sanger Institute, Cambridge, UK Wolfson Brain Imaging Centre University of Cambridge, Cambridge, UK National Institute for Health Research/Wellcome Trust Clinical Research Facility Cambridge, UK
| | | | - David B Savage
- The University of Cambridge Metabolic Research Laboratories Wellcome Trust-MRC Institute of Metabolic Science, Cambridge, UK The National Institute for Health Research Cambridge Biomedical Research Centre Cambridge, UK Department of Pediatrics Sapienza University, Rome, Italy Metabolic Disease Group Wellcome Trust Sanger Institute, Cambridge, UK Wolfson Brain Imaging Centre University of Cambridge, Cambridge, UK National Institute for Health Research/Wellcome Trust Clinical Research Facility Cambridge, UK The University of Cambridge Metabolic Research Laboratories Wellcome Trust-MRC Institute of Metabolic Science, Cambridge, UK The National Institute for Health Research Cambridge Biomedical Research Centre Cambridge, UK Department of Pediatrics Sapienza University, Rome, Italy Metabolic Disease Group Wellcome Trust Sanger Institute, Cambridge, UK Wolfson Brain Imaging Centre University of Cambridge, Cambridge, UK National Institute for Health Research/Wellcome Trust Clinical Research Facility Cambridge, UK
| | - Stephen O'Rahilly
- The University of Cambridge Metabolic Research Laboratories Wellcome Trust-MRC Institute of Metabolic Science, Cambridge, UK The National Institute for Health Research Cambridge Biomedical Research Centre Cambridge, UK Department of Pediatrics Sapienza University, Rome, Italy Metabolic Disease Group Wellcome Trust Sanger Institute, Cambridge, UK Wolfson Brain Imaging Centre University of Cambridge, Cambridge, UK National Institute for Health Research/Wellcome Trust Clinical Research Facility Cambridge, UK The University of Cambridge Metabolic Research Laboratories Wellcome Trust-MRC Institute of Metabolic Science, Cambridge, UK The National Institute for Health Research Cambridge Biomedical Research Centre Cambridge, UK Department of Pediatrics Sapienza University, Rome, Italy Metabolic Disease Group Wellcome Trust Sanger Institute, Cambridge, UK Wolfson Brain Imaging Centre University of Cambridge, Cambridge, UK National Institute for Health Research/Wellcome Trust Clinical Research Facility Cambridge, UK
| | - Robert K Semple
- The University of Cambridge Metabolic Research Laboratories Wellcome Trust-MRC Institute of Metabolic Science, Cambridge, UK The National Institute for Health Research Cambridge Biomedical Research Centre Cambridge, UK Department of Pediatrics Sapienza University, Rome, Italy Metabolic Disease Group Wellcome Trust Sanger Institute, Cambridge, UK Wolfson Brain Imaging Centre University of Cambridge, Cambridge, UK National Institute for Health Research/Wellcome Trust Clinical Research Facility Cambridge, UK The University of Cambridge Metabolic Research Laboratories Wellcome Trust-MRC Institute of Metabolic Science, Cambridge, UK The National Institute for Health Research Cambridge Biomedical Research Centre Cambridge, UK Department of Pediatrics Sapienza University, Rome, Italy Metabolic Disease Group Wellcome Trust Sanger Institute, Cambridge, UK Wolfson Brain Imaging Centre University of Cambridge, Cambridge, UK National Institute for Health Research/Wellcome Trust Clinical Research Facility Cambridge, UK
| | - Inês Barroso
- The University of Cambridge Metabolic Research Laboratories Wellcome Trust-MRC Institute of Metabolic Science, Cambridge, UK The National Institute for Health Research Cambridge Biomedical Research Centre Cambridge, UK Department of Pediatrics Sapienza University, Rome, Italy Metabolic Disease Group Wellcome Trust Sanger Institute, Cambridge, UK Wolfson Brain Imaging Centre University of Cambridge, Cambridge, UK National Institute for Health Research/Wellcome Trust Clinical Research Facility Cambridge, UK The University of Cambridge Metabolic Research Laboratories Wellcome Trust-MRC Institute of Metabolic Science, Cambridge, UK The National Institute for Health Research Cambridge Biomedical Research Centre Cambridge, UK Department of Pediatrics Sapienza University, Rome, Italy Metabolic Disease Group Wellcome Trust Sanger Institute, Cambridge, UK Wolfson Brain Imaging Centre University of Cambridge, Cambridge, UK National Institute for Health Research/Wellcome Trust Clinical Research Facility Cambridge, UK The University of Cambridge Metabolic Research Laboratories Wellcome Trust-MRC Institute of Metabolic Science, Cambridge, UK The National Institute for Health Research Cambridge Biomedical Research Centre Cambridge, UK Department of Pediatrics Sapienza University, Rome, Italy Metabolic Disease Group Wellcome Trust Sanger Institute, Cambridge, UK Wolfson Brain Imaging Centre University of Cambridge, Cambridge, UK National Institute for Health Research/Wellcome Trust Clinical Research Facility Cambridge, UK
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Barraza-García J, Iván Rivera-Pedroza C, Salamanca L, Belinchón A, López-González V, Sentchordi-Montané L, del Pozo Á, Santos-Simarro F, Campos-Barros Á, Lapunzina P, Guillén-Navarro E, González-Casado I, García-Miñaur S, Heath KE. Two novelPOC1Amutations in the primordial dwarfism, SOFT syndrome: Clinical homogeneity but also unreported malformations. Am J Med Genet A 2015; 170A:210-6. [DOI: 10.1002/ajmg.a.37393] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 09/07/2015] [Indexed: 11/10/2022]
Affiliation(s)
- Jimena Barraza-García
- Institute of Medical & Molecular Genetics (INGEMM); Hospital Universitario La Paz; Universidad Autónoma de Madrid; IdiPAZ Madrid Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER); Instituto Carlos III; Madrid Spain
- Multidisciplinary Skeletal Dysplasia Unit (UMDE); Hospital Universitario La Paz; Madrid Spain
| | - Carlos Iván Rivera-Pedroza
- Institute of Medical & Molecular Genetics (INGEMM); Hospital Universitario La Paz; Universidad Autónoma de Madrid; IdiPAZ Madrid Spain
- Multidisciplinary Skeletal Dysplasia Unit (UMDE); Hospital Universitario La Paz; Madrid Spain
| | - Luis Salamanca
- Department of Pediatric Endocrinology; Hospital Universitario La Paz; Universidad Autónoma de Madrid; Spain
| | - Alberta Belinchón
- Institute of Medical & Molecular Genetics (INGEMM); Hospital Universitario La Paz; Universidad Autónoma de Madrid; IdiPAZ Madrid Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER); Instituto Carlos III; Madrid Spain
- Multidisciplinary Skeletal Dysplasia Unit (UMDE); Hospital Universitario La Paz; Madrid Spain
| | - Vanesa López-González
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER); Instituto Carlos III; Madrid Spain
- Department of Pediatrics; Medical Genetics Section; Hospital Clínico Universitario Virgen de la Arrixaca; IMIB-Arrixaca; Murcia Spain
| | - Lucía Sentchordi-Montané
- Institute of Medical & Molecular Genetics (INGEMM); Hospital Universitario La Paz; Universidad Autónoma de Madrid; IdiPAZ Madrid Spain
- Multidisciplinary Skeletal Dysplasia Unit (UMDE); Hospital Universitario La Paz; Madrid Spain
- Department of Pediatric Endocrinology; Hospital Universitario Infanta Leonor; Madrid Spain
| | - Ángela del Pozo
- Institute of Medical & Molecular Genetics (INGEMM); Hospital Universitario La Paz; Universidad Autónoma de Madrid; IdiPAZ Madrid Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER); Instituto Carlos III; Madrid Spain
| | - Fernando Santos-Simarro
- Institute of Medical & Molecular Genetics (INGEMM); Hospital Universitario La Paz; Universidad Autónoma de Madrid; IdiPAZ Madrid Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER); Instituto Carlos III; Madrid Spain
- Multidisciplinary Skeletal Dysplasia Unit (UMDE); Hospital Universitario La Paz; Madrid Spain
| | - Ángel Campos-Barros
- Institute of Medical & Molecular Genetics (INGEMM); Hospital Universitario La Paz; Universidad Autónoma de Madrid; IdiPAZ Madrid Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER); Instituto Carlos III; Madrid Spain
| | - Pablo Lapunzina
- Institute of Medical & Molecular Genetics (INGEMM); Hospital Universitario La Paz; Universidad Autónoma de Madrid; IdiPAZ Madrid Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER); Instituto Carlos III; Madrid Spain
- Multidisciplinary Skeletal Dysplasia Unit (UMDE); Hospital Universitario La Paz; Madrid Spain
| | - Encarna Guillén-Navarro
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER); Instituto Carlos III; Madrid Spain
- Department of Pediatrics; Medical Genetics Section; Hospital Clínico Universitario Virgen de la Arrixaca; IMIB-Arrixaca; Murcia Spain
- Cátedra de Genética Médica; UCAM-Universidad Católica San Antonio de Murcia; Spain
| | - Isabel González-Casado
- Multidisciplinary Skeletal Dysplasia Unit (UMDE); Hospital Universitario La Paz; Madrid Spain
- Department of Pediatric Endocrinology; Hospital Universitario La Paz; Universidad Autónoma de Madrid; Spain
| | - Sixto García-Miñaur
- Institute of Medical & Molecular Genetics (INGEMM); Hospital Universitario La Paz; Universidad Autónoma de Madrid; IdiPAZ Madrid Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER); Instituto Carlos III; Madrid Spain
- Multidisciplinary Skeletal Dysplasia Unit (UMDE); Hospital Universitario La Paz; Madrid Spain
| | - Karen E. Heath
- Institute of Medical & Molecular Genetics (INGEMM); Hospital Universitario La Paz; Universidad Autónoma de Madrid; IdiPAZ Madrid Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER); Instituto Carlos III; Madrid Spain
- Multidisciplinary Skeletal Dysplasia Unit (UMDE); Hospital Universitario La Paz; Madrid Spain
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Dong G. Building a ninefold symmetrical barrel: structural dissections of centriole assembly. Open Biol 2015; 5:150082. [PMID: 26269428 PMCID: PMC4554922 DOI: 10.1098/rsob.150082] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Accepted: 07/21/2015] [Indexed: 01/27/2023] Open
Abstract
Centrioles are short microtubule-based organelles with a conserved ninefold symmetry. They are essential for both centrosome formation and cilium biogenesis in most eukaryotes. A core set of five centriolar proteins has been identified and their sequential recruitment to procentrioles has been established. However, structures at atomic resolution for most of the centriolar components were scarce, and the underlying molecular mechanisms for centriole assembly had been a mystery--until recently. In this review, I briefly summarize recent advancements in high-resolution structural characterization of the core centriolar components and discuss perspectives in the field.
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Affiliation(s)
- Gang Dong
- Max F. Perutz Laboratories, Medical University of Vienna, Vienna 1030, Austria
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70
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Zhang C, Zhang Q, Wang F, Liu Q. Knockdown of poc1b causes abnormal photoreceptor sensory cilium and vision impairment in zebrafish. Biochem Biophys Res Commun 2015; 465:651-7. [PMID: 26188096 DOI: 10.1016/j.bbrc.2015.06.083] [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: 06/03/2015] [Accepted: 06/12/2015] [Indexed: 01/26/2023]
Abstract
Proteomic analysis of the mouse photoreceptor sensory cilium identified a set of cilia proteins, including Poc1 centriolar protein b (Poc1b). Previous functional studies in human cells and zebrafish embryos implicated that Poc1b plays important roles in centriole duplication and length control, as well as ciliogenesis. To study the function of Poc1b in photoreceptor sensory cilia and other primary cilia, we expressed a tagged recombinant Poc1b protein in cultured renal epithelial cells and rat retina. Poc1b was localized to the centrioles and spindle bundles during cell cycle progression, and to the basal body of photoreceptor sensory cilia. A morpholino knockdown and complementation assay of poc1b in zebrafish showed that loss of poc1b led to a range of morphological anomalies of cilia commonly associated with human ciliopathies. In the retina, the development of retinal laminae was significantly delayed and the length of photoreceptor outer segments was shortened. Visual behavior studies revealed impaired visual function in the poc1b morphants. In addition, ciliopathy-associated developmental defects, such as small eyes, curved body axis, heart defects, and shortened cilia in Kupffer's vesicle, were observed as well. These data suggest that poc1b is required for normal development and ciliogenesis of retinal photoreceptor sensory cilia and other cilia. Furthermore, this conclusion is supported by recent findings that mutations in POC1B gene have been identified in patients with inherited retinal dystrophy and syndromic retinal ciliopathy.
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Affiliation(s)
- Conghui Zhang
- Department of Ophthalmology, Shanghai Tenth People's Hospital, Tongji University, Shanghai, China
| | - Qi Zhang
- Ocular Genomics Institute, Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, USA
| | - Fang Wang
- Department of Ophthalmology, Shanghai Tenth People's Hospital, Tongji University, Shanghai, China.
| | - Qin Liu
- Ocular Genomics Institute, Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, USA; Berman-Gund Laboratory for the Study of Retinal Degenerations, Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, USA.
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71
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Gonçalves J, Tavares A, Carvalhal S, Soares H. Revisiting the tubulin folding pathway: new roles in centrosomes and cilia. Biomol Concepts 2015; 1:423-34. [PMID: 25962015 DOI: 10.1515/bmc.2010.033] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Centrosomes and cilia are critical eukaryotic organelles which have been in the spotlight in recent years given their implication in a myriad of cellular and developmental processes. Despite their recognized importance and intense study, there are still many open questions about their biogenesis and function. In the present article, we review the existing data concerning members of the tubulin folding pathway and related proteins, which have been identified at centrosomes and cilia and were shown to have unexpected roles in these structures.
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72
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Abstract
Centrioles are among the largest protein-based structures found in most cell types, measuring approximately 250 nm in diameter and approximately 500 nm long in vertebrate cells. Here, we briefly review ultrastructural observations about centrioles and associated structures. At the core of most centrioles is a microtubule scaffold formed from a radial array of nine triplet microtubules. Beyond the microtubule triplets of the centriole, we discuss the critically important cartwheel structure and the more enigmatic luminal density, both found on the inside of the centriole. Finally, we discuss the connectors between centrioles, and the distal and subdistal appendages outside of the microtubule scaffold that reflect centriole age and impart special functions to the centriole. Most of the work we review has been done with electron microscopy or electron tomography of resin-embedded samples, but we also highlight recent work performed with cryoelectron microscopy, cryotomography and subvolume averaging. Significant opportunities remain in the description of centriolar structure, both in mapping of component proteins within the structure and in determining the effect of mutations on components that contribute to the structure and function of the centriole.
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Affiliation(s)
- Mark Winey
- Molecular, Cellular and Developmental Biology, University of Colorado at Boulder, Boulder, CO 80309, USA
| | - Eileen O'Toole
- Molecular, Cellular and Developmental Biology, University of Colorado at Boulder, Boulder, CO 80309, USA The Boulder Laboratory for the 3D EM of Cells, Molecular, Cellular and Developmental Biology, University of Colorado at Boulder, Boulder, CO 80309, USA
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Abstract
The cartwheel is a subcentriolar structure consisting of a central hub and nine radially arranged spokes, located at the proximal end of the centriole. It appears at the initial stage of the centriole assembly process as the first ninefold symmetrical structure. The cartwheel was first described more than 50 years ago, but it is only recently that its pivotal role in establishing the ninefold symmetry of the centriole was demonstrated. Significant progress has since been made in understanding its fine structure and assembly mechanism. Most importantly, the central part of the cartwheel, from which the ninefold symmetry originates, is shown to form by self-association of nine dimers of the protein SAS-6. This finding, together with emerging data on other components of the cartwheel, has opened new avenues in centrosome biology.
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Affiliation(s)
- Masafumi Hirono
- Department of Biological Sciences, University of Tokyo, Tokyo, Japan
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74
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Galati DF, Bonney S, Kronenberg Z, Clarissa C, Yandell M, Elde NC, Jerka-Dziadosz M, Giddings TH, Frankel J, Pearson CG. DisAp-dependent striated fiber elongation is required to organize ciliary arrays. ACTA ACUST UNITED AC 2015; 207:705-15. [PMID: 25533842 PMCID: PMC4274257 DOI: 10.1083/jcb.201409123] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
DisAp is a novel kinetodesmal fiber component that is essential for force-dependent fiber elongation and the alignment of basal body orientation in multiciliary arrays. Cilia-organizing basal bodies (BBs) are microtubule scaffolds that are visibly asymmetrical because they have attached auxiliary structures, such as striated fibers. In multiciliated cells, BB orientation aligns to ensure coherent ciliary beating, but the mechanisms that maintain BB orientation are unclear. For the first time in Tetrahymena thermophila, we use comparative whole-genome sequencing to identify the mutation in the BB disorientation mutant disA-1. disA-1 abolishes the localization of the novel protein DisAp to T.thermophila striated fibers (kinetodesmal fibers; KFs), which is consistent with DisAp’s similarity to the striated fiber protein SF-assemblin. We demonstrate that DisAp is required for KFs to elongate and to resist BB disorientation in response to ciliary forces. Newly formed BBs move along KFs as they approach their cortical attachment sites. However, because they contain short KFs that are rotated, BBs in disA-1 cells display aberrant spacing and disorientation. Therefore, DisAp is a novel KF component that is essential for force-dependent KF elongation and BB orientation in multiciliary arrays.
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Affiliation(s)
- Domenico F Galati
- Anschutz Medical Campus, Department of Cell and Developmental Biology, University of Colorado, Aurora, CO 80045
| | - Stephanie Bonney
- Anschutz Medical Campus, Department of Cell and Developmental Biology, University of Colorado, Aurora, CO 80045
| | - Zev Kronenberg
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, UT 84112
| | - Christina Clarissa
- Molecular, Cellular and Developmental Biology, University of Colorado at Boulder, Boulder, CO 80309
| | - Mark Yandell
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, UT 84112
| | - Nels C Elde
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, UT 84112
| | - Maria Jerka-Dziadosz
- Department of Cell Biology, M. Nencki Institute of Experimental Biology, 02-093 Warsaw, Poland
| | - Thomas H Giddings
- Molecular, Cellular and Developmental Biology, University of Colorado at Boulder, Boulder, CO 80309
| | - Joseph Frankel
- Department of Biological Sciences, University of Iowa, Iowa City, IA 52242
| | - Chad G Pearson
- Anschutz Medical Campus, Department of Cell and Developmental Biology, University of Colorado, Aurora, CO 80045
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75
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Christou-Savina S, Beales PL, Osborn DPS. Evaluation of zebrafish kidney function using a fluorescent clearance assay. J Vis Exp 2015:e52540. [PMID: 25742415 DOI: 10.3791/52540] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The zebrafish embryo offers a tractable model to study organogenesis and model human genetic disease. Despite its relative simplicity, the zebrafish kidney develops and functions in almost the same way as humans. A major difference in the construction of the human kidney is the presence of millions of nephrons compared to the zebrafish that has only two. However, simplifying such a complex system into basic functional units has aided our understanding of how the kidney develops and operates. In zebrafish, the midline located glomerulus is responsible for the initial blood filtration into two pronephric tubules that diverge to run bilaterally down the embryonic axis before fusing to each other at the cloaca. The pronephric tubules are heavily populated by motile cilia that facilitate the movement of filtrate along the segmented tubule, allowing the exchange of various solutes before finally exiting via the cloaca. Many genes responsible for CKD, including those related to ciliogenesis, have been studied in zebrafish. However, a major draw back has been the difficulty in evaluating zebrafish kidney function after genetic manipulation. Traditional assays to measure kidney dysfunction in humans have proved non translational to zebrafish, mainly due to their aquatic environment and small size. For example, it is not physically possible to extract blood from embryonic staged fish for analysis of urea and creatinine content, as they are too small. In addition, zebrafish do not produce enough urine for testing on a simple proteinuria 'dipstick', which is often performed during initial patient examinations. We describe a fluorescent assay that utilizes the optical transparency of the zebrafish to quantitatively monitor the clearance of a fluorescent dye, over time, from the vasculature and out through the kidney, to give a read out of renal function.
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Affiliation(s)
| | - Philip L Beales
- Genetics and Genomic Medicine, Institute of Child Health, University College London
| | - Daniel P S Osborn
- Molecular Cell Science Research Centre, St. George's University of London;
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von Tobel L, Mikeladze-Dvali T, Delattre M, Balestra FR, Blanchoud S, Finger S, Knott G, Müller-Reichert T, Gönczy P. SAS-1 is a C2 domain protein critical for centriole integrity in C. elegans. PLoS Genet 2014; 10:e1004777. [PMID: 25412110 PMCID: PMC4238951 DOI: 10.1371/journal.pgen.1004777] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 09/25/2014] [Indexed: 02/06/2023] Open
Abstract
Centrioles are microtubule-based organelles important for the formation of cilia, flagella and centrosomes. Despite progress in understanding the underlying assembly mechanisms, how centriole integrity is ensured is incompletely understood, including in sperm cells, where such integrity is particularly critical. We identified C. elegans sas-1 in a genetic screen as a locus required for bipolar spindle assembly in the early embryo. Our analysis reveals that sperm-derived sas-1 mutant centrioles lose their integrity shortly after fertilization, and that a related defect occurs when maternal sas-1 function is lacking. We establish that sas-1 encodes a C2 domain containing protein that localizes to centrioles in C. elegans, and which can bind and stabilize microtubules when expressed in human cells. Moreover, we uncover that SAS-1 is related to C2CD3, a protein required for complete centriole formation in human cells and affected in a type of oral-facial-digital (OFD) syndrome. Centrioles are microtubule-based organelles critical for forming cilia, flagella and centrosomes. Centrioles are very stable, but how such stability is ensured is poorly understood. We identified sas-1 as a component that contributes to centriole stability in C. elegans. Centrioles that lack sas-1 function loose their integrity, and our analysis reveals that sas-1 is particularly important for sperm-derived centrioles. Moreover, we show that SAS-1 binds and stabilizes microtubules in human cells, together leading us to propose that SAS-1 acts by stabilizing centriolar microtubules. We identify C2CD3 as a human homolog of SAS-1. C2CD3 is needed for the presence of the distal part of centrioles in human cells, and we thus propose that this protein family is broadly needed to maintain centriole structure.
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Affiliation(s)
- Lukas von Tobel
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology (EPFL) Lausanne, Switzerland
| | - Tamara Mikeladze-Dvali
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology (EPFL) Lausanne, Switzerland
| | - Marie Delattre
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology (EPFL) Lausanne, Switzerland
| | - Fernando R. Balestra
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology (EPFL) Lausanne, Switzerland
| | - Simon Blanchoud
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology (EPFL) Lausanne, Switzerland
| | - Susanne Finger
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Graham Knott
- BioEM Facility, School of Life Sciences, Swiss Federal Institute of Technology (EPFL) Lausanne, Switzerland
| | - Thomas Müller-Reichert
- Structural Cell Biology Group, Experimental Center, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Pierre Gönczy
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology (EPFL) Lausanne, Switzerland
- * E-mail:
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Beck BB, Phillips JB, Bartram MP, Wegner J, Thoenes M, Pannes A, Sampson J, Heller R, Göbel H, Koerber F, Neugebauer A, Hedergott A, Nürnberg G, Nürnberg P, Thiele H, Altmüller J, Toliat MR, Staubach S, Boycott KM, Valente EM, Janecke AR, Eisenberger T, Bergmann C, Tebbe L, Wang Y, Wu Y, Fry AM, Westerfield M, Wolfrum U, Bolz HJ. Mutation of POC1B in a severe syndromic retinal ciliopathy. Hum Mutat 2014; 35:1153-62. [PMID: 25044745 PMCID: PMC4425427 DOI: 10.1002/humu.22618] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Accepted: 07/12/2014] [Indexed: 12/20/2022]
Abstract
We describe a consanguineous Iraqi family with Leber congenital amaurosis (LCA), Joubert syndrome (JBTS), and polycystic kidney disease (PKD). Targeted next-generation sequencing for excluding mutations in known LCA and JBTS genes, homozygosity mapping, and whole-exome sequencing identified a homozygous missense variant, c.317G>C (p.Arg106Pro), in POC1B, a gene essential for ciliogenesis, basal body, and centrosome integrity. In silico modeling suggested a requirement of p.Arg106 for the formation of the third WD40 repeat and a protein interaction interface. In human and mouse retina, POC1B localized to the basal body and centriole adjacent to the connecting cilium of photoreceptors and in synapses of the outer plexiform layer. Knockdown of Poc1b in zebrafish caused cystic kidneys and retinal degeneration with shortened and reduced photoreceptor connecting cilia, compatible with the human syndromic ciliopathy. A recent study describes homozygosity for p.Arg106ProPOC1B in a family with nonsyndromic cone-rod dystrophy. The phenotype associated with homozygous p.Arg106ProPOC1B may thus be highly variable, analogous to homozygous p.Leu710Ser in WDR19 causing either isolated retinitis pigmentosa or Jeune syndrome. Our study indicates that POC1B is required for retinal integrity, and we propose POC1B mutations as a probable cause for JBTS with severe PKD.
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Affiliation(s)
- Bodo B. Beck
- Institute of Human Genetics, University Hospital of Cologne, 50931 Cologne, Germany
| | | | - Malte P. Bartram
- Department II of Internal Medicine and Center for Molecular Medicine Cologne, University Hospital of Cologne, 50931 Cologne, Germany
| | - Jeremy Wegner
- Institute of Neuroscience, University of Oregon, 97401 Eugene, Oregon, USA
| | - Michaela Thoenes
- Institute of Human Genetics, University Hospital of Cologne, 50931 Cologne, Germany
| | - Andrea Pannes
- Institute of Human Genetics, University Hospital of Cologne, 50931 Cologne, Germany
| | - Josephina Sampson
- Department of Biochemistry, University of Leicester, Leicester, United Kingdom, LE7 9HN
| | - Raoul Heller
- Institute of Human Genetics, University Hospital of Cologne, 50931 Cologne, Germany
| | - Heike Göbel
- Department of Pathology, University Hospital of Cologne, 50931 Cologne, Germany
| | - Friederike Koerber
- Department of Radiology, University Hospital of Cologne, 50931 Cologne, Germany
| | - Antje Neugebauer
- Department of Ophthalmology, University Hospital of Cologne, 50931 Cologne, Germany
| | - Andrea Hedergott
- Department of Ophthalmology, University Hospital of Cologne, 50931 Cologne, Germany
| | - Gudrun Nürnberg
- Cologne Center for Genomics (CCG) and Centre for Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany
| | - Peter Nürnberg
- Cologne Center for Genomics (CCG) and Centre for Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, 50931 Cologne, Germany
| | - Holger Thiele
- Cologne Center for Genomics (CCG) and Centre for Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany
| | - Janine Altmüller
- Institute of Human Genetics, University Hospital of Cologne, 50931 Cologne, Germany
- Cologne Center for Genomics (CCG) and Centre for Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany
| | - Mohammad R. Toliat
- Cologne Center for Genomics (CCG) and Centre for Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany
| | - Simon Staubach
- Institute of Human Genetics, University Hospital of Cologne, 50931 Cologne, Germany
| | - Kym M. Boycott
- Children’s Hospital of Eastern Ontario Research Institute, University of Ottawa, K1H 8L1 Ottawa, Canada
| | - Enza Maria Valente
- Mendel Laboratory, IRCCS Casa Sollievo della Sofferenza Institute, 71013 San Giovanni Rotondo, Italy
- Department of Medicine and Surgery, University of Salerno, 84080 Salerno, Italy
| | - Andreas R. Janecke
- Department of Pediatrics I, and Division of Human Genetics, Innsbruck Medical University, 6020 Innsbruck, Austria
| | | | - Carsten Bergmann
- Center for Human Genetics, Bioscientia, 55218 Ingelheim, Germany
- Department of Medicine, Renal Division, University of Freiburg Medical Center, 79095 Freiburg, Germany
| | - Lars Tebbe
- Department of Cell and Matrix Biology, Institute of Zoology, Johannes Gutenberg, University of Mainz, 55099 Mainz, Germany
| | - Yang Wang
- Lab of Computational Chemistry and Drug Design, Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, 518000 Shenzhen, P. R. China
| | - Yundong Wu
- Lab of Computational Chemistry and Drug Design, Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, 518000 Shenzhen, P. R. China
- College of Chemistry, Peking University, 100871 Beijing, P. R. China
| | - Andrew M. Fry
- Department of Biochemistry, University of Leicester, Leicester, United Kingdom, LE7 9HN
| | - Monte Westerfield
- Institute of Neuroscience, University of Oregon, 97401 Eugene, Oregon, USA
| | - Uwe Wolfrum
- Department of Cell and Matrix Biology, Institute of Zoology, Johannes Gutenberg, University of Mainz, 55099 Mainz, Germany
- Focus Program Translational Neurosciences (FTN), Johannes Gutenberg University of Mainz, 55122 Mainz, Germany
| | - Hanno J. Bolz
- Institute of Human Genetics, University Hospital of Cologne, 50931 Cologne, Germany
- Center for Human Genetics, Bioscientia, 55218 Ingelheim, Germany
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Basal foot MTOC organizes pillar MTs required for coordination of beating cilia. Nat Commun 2014; 5:4888. [PMID: 25215410 PMCID: PMC4993237 DOI: 10.1038/ncomms5888] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Accepted: 08/01/2014] [Indexed: 12/05/2022] Open
Abstract
Coordination of ciliary beating is essential to ensure mucus clearance in
the airway tract. The orientation and synchronization of ciliary motion responds
in part to the organization of the underlying cytoskeletal networks. Using
electron tomography on mouse trachea, we show that basal bodies are collectively
hooked at the cortex by a regular microtubule array composed of 4-5
microtubules. Removal of Galectin-3, one of basal body components, provokes
misrecruitment of γ-tubulin, disorganization of this microtubule
framework emanating from the basal foot cap, together with loss of basal body
alignment and cilium orientation, defects in cilium organization and reduced
fluid flow in the tracheal lumen. We conclude that Galectin-3 plays a crucial
role in the maintenance of the microtubule organizing center of the cilium and
the “pillar” microtubules, and that this network is instrumental
for the coordinated orientation and stabilization of motile cilia.
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79
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Roosing S, Lamers IJC, de Vrieze E, van den Born LI, Lambertus S, Arts HH, Peters TA, Hoyng CB, Kremer H, Hetterschijt L, Letteboer SJF, van Wijk E, Roepman R, den Hollander AI, Cremers FPM. Disruption of the basal body protein POC1B results in autosomal-recessive cone-rod dystrophy. Am J Hum Genet 2014; 95:131-42. [PMID: 25018096 PMCID: PMC4129401 DOI: 10.1016/j.ajhg.2014.06.012] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2014] [Accepted: 06/19/2014] [Indexed: 12/11/2022] Open
Abstract
Exome sequencing revealed a homozygous missense mutation (c.317C>G [p.Arg106Pro]) in POC1B, encoding POC1 centriolar protein B, in three siblings with autosomal-recessive cone dystrophy or cone-rod dystrophy and compound-heterozygous POC1B mutations (c.199_201del [p.Gln67del] and c.810+1G>T) in an unrelated person with cone-rod dystrophy. Upon overexpression of POC1B in human TERT-immortalized retinal pigment epithelium 1 cells, the encoded wild-type protein localized to the basal body of the primary cilium, whereas this localization was lost for p.Arg106Pro and p.Gln67del variant forms of POC1B. Morpholino-oligonucleotide-induced knockdown of poc1b translation in zebrafish resulted in a dose-dependent small-eye phenotype, impaired optokinetic responses, and decreased length of photoreceptor outer segments. These ocular phenotypes could partially be rescued by wild-type human POC1B mRNA, but not by c.199_201del and c.317C>G mutant human POC1B mRNAs. Yeast two-hybrid screening of a human retinal cDNA library revealed FAM161A as a binary interaction partner of POC1B. This was confirmed in coimmunoprecipitation and colocalization assays, which both showed loss of FAM161A interaction with p.Arg106Pro and p.Gln67del variant forms of POC1B. FAM161A was previously implicated in autosomal-recessive retinitis pigmentosa and shown to be located at the base of the photoreceptor connecting cilium, where it interacts with several other ciliopathy-associated proteins. Altogether, this study demonstrates that POC1B mutations result in a defect of the photoreceptor sensory cilium and thus affect cone and rod photoreceptors.
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Affiliation(s)
- Susanne Roosing
- Department of Human Genetics, Radboud University Medical Center, PO Box 9101, 6500 HB Nijmegen, the Netherlands; Radboud Institute for Molecular Life Sciences, Radboud University Nijmegen, PO Box 9101, 6500 HB Nijmegen, the Netherlands
| | - Ideke J C Lamers
- Department of Human Genetics, Radboud University Medical Center, PO Box 9101, 6500 HB Nijmegen, the Netherlands; Radboud Institute for Molecular Life Sciences, Radboud University Nijmegen, PO Box 9101, 6500 HB Nijmegen, the Netherlands
| | - Erik de Vrieze
- Department of Human Genetics, Radboud University Medical Center, PO Box 9101, 6500 HB Nijmegen, the Netherlands; Department of Otorhinolaryngology, Radboud University Medical Center, PO Box 9101, 6500 HB Nijmegen, the Netherlands
| | | | - Stanley Lambertus
- Department of Ophthalmology, Radboud University Medical Center, PO Box 9101, 6500 HB Nijmegen, the Netherlands
| | - Heleen H Arts
- Department of Human Genetics, Radboud University Medical Center, PO Box 9101, 6500 HB Nijmegen, the Netherlands; Radboud Institute for Molecular Life Sciences, Radboud University Nijmegen, PO Box 9101, 6500 HB Nijmegen, the Netherlands
| | - Theo A Peters
- Department of Otorhinolaryngology, Radboud University Medical Center, PO Box 9101, 6500 HB Nijmegen, the Netherlands
| | - Carel B Hoyng
- Department of Ophthalmology, Radboud University Medical Center, PO Box 9101, 6500 HB Nijmegen, the Netherlands
| | - Hannie Kremer
- Department of Human Genetics, Radboud University Medical Center, PO Box 9101, 6500 HB Nijmegen, the Netherlands; Radboud Institute for Molecular Life Sciences, Radboud University Nijmegen, PO Box 9101, 6500 HB Nijmegen, the Netherlands; Department of Otorhinolaryngology, Radboud University Medical Center, PO Box 9101, 6500 HB Nijmegen, the Netherlands
| | - Lisette Hetterschijt
- Department of Human Genetics, Radboud University Medical Center, PO Box 9101, 6500 HB Nijmegen, the Netherlands
| | - Stef J F Letteboer
- Department of Human Genetics, Radboud University Medical Center, PO Box 9101, 6500 HB Nijmegen, the Netherlands; Radboud Institute for Molecular Life Sciences, Radboud University Nijmegen, PO Box 9101, 6500 HB Nijmegen, the Netherlands
| | - Erwin van Wijk
- Department of Otorhinolaryngology, Radboud University Medical Center, PO Box 9101, 6500 HB Nijmegen, the Netherlands
| | - Ronald Roepman
- Department of Human Genetics, Radboud University Medical Center, PO Box 9101, 6500 HB Nijmegen, the Netherlands; Radboud Institute for Molecular Life Sciences, Radboud University Nijmegen, PO Box 9101, 6500 HB Nijmegen, the Netherlands
| | - Anneke I den Hollander
- Department of Human Genetics, Radboud University Medical Center, PO Box 9101, 6500 HB Nijmegen, the Netherlands; Radboud Institute for Molecular Life Sciences, Radboud University Nijmegen, PO Box 9101, 6500 HB Nijmegen, the Netherlands; Department of Ophthalmology, Radboud University Medical Center, PO Box 9101, 6500 HB Nijmegen, the Netherlands
| | - Frans P M Cremers
- Department of Human Genetics, Radboud University Medical Center, PO Box 9101, 6500 HB Nijmegen, the Netherlands; Radboud Institute for Molecular Life Sciences, Radboud University Nijmegen, PO Box 9101, 6500 HB Nijmegen, the Netherlands.
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80
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Osborn DPS, Roccasecca RM, McMurray F, Hernandez-Hernandez V, Mukherjee S, Barroso I, Stemple D, Cox R, Beales PL, Christou-Savina S. Loss of FTO antagonises Wnt signaling and leads to developmental defects associated with ciliopathies. PLoS One 2014; 9:e87662. [PMID: 24503721 PMCID: PMC3913654 DOI: 10.1371/journal.pone.0087662] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Accepted: 12/27/2013] [Indexed: 11/24/2022] Open
Abstract
Common intronic variants in the Human fat mass and obesity-associated gene (FTO) are found to be associated with an increased risk of obesity. Overexpression of FTO correlates with increased food intake and obesity, whilst loss-of-function results in lethality and severe developmental defects. Despite intense scientific discussions around the role of FTO in energy metabolism, the function of FTO during development remains undefined. Here, we show that loss of Fto leads to developmental defects such as growth retardation, craniofacial dysmorphism and aberrant neural crest cells migration in Zebrafish. We find that the important developmental pathway, Wnt, is compromised in the absence of FTO, both in vivo (zebrafish) and in vitro (Fto−/− MEFs and HEK293T). Canonical Wnt signalling is down regulated by abrogated β-Catenin translocation to the nucleus whilst non-canonical Wnt/Ca2+ pathway is activated via its key signal mediators CaMKII and PKCδ. Moreover, we demonstrate that loss of Fto results in short, absent or disorganised cilia leading to situs inversus, renal cystogenesis, neural crest cell defects and microcephaly in Zebrafish. Congruently, Fto knockout mice display aberrant tissue specific cilia. These data identify FTO as a protein-regulator of the balanced activation between canonical and non-canonical branches of the Wnt pathway. Furthermore, we present the first evidence that FTO plays a role in development and cilia formation/function.
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Affiliation(s)
- Daniel P. S. Osborn
- Biomedical Sciences, St George’s University of London, London, United Kingdom
| | - Rosa Maria Roccasecca
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Cambridge, United Kingdom
| | - Fiona McMurray
- Harwell Science and Innovation Campus, MRC Harwell, Harwell, United Kingdom
| | | | - Sriparna Mukherjee
- Molecular Medicine Unit, Institute of Child Health, University College London, London, United Kingdom
| | - Inês Barroso
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Cambridge, United Kingdom
- University of Cambridge Metabolic Research Laboratories and NIHR Cambridge Biomedical Research Centre, Institute of Metabolic Science, Addenbrooke’s Hospital, Cambridge, United Kingdom
| | - Derek Stemple
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Cambridge, United Kingdom
| | - Roger Cox
- Harwell Science and Innovation Campus, MRC Harwell, Harwell, United Kingdom
| | - Philip L. Beales
- Molecular Medicine Unit, Institute of Child Health, University College London, London, United Kingdom
- * E-mail:
| | - Sonia Christou-Savina
- Molecular Medicine Unit, Institute of Child Health, University College London, London, United Kingdom
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81
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Dutcher SK. The awesome power of dikaryons for studying flagella and basal bodies in Chlamydomonas reinhardtii. Cytoskeleton (Hoboken) 2013; 71:79-94. [PMID: 24272949 DOI: 10.1002/cm.21157] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Accepted: 11/19/2013] [Indexed: 11/08/2022]
Abstract
Cilia/flagella and basal bodies/centrioles play key roles in human health and homeostasis. Among the organisms used to study these microtubule-based organelles, the green alga Chlamydomonas reinhardtii has several advantages. One is the existence of a temporary phase of the life cycle, termed the dikaryon. These cells are formed during mating when the cells fuse and the behavior of flagella from two genetically distinguishable parents can be observed. During this stage, the cytoplasms mix allowing for a defect in the flagella of one parent to be rescued by proteins from the other parent. This offers the unique advantage of adding back wild-type gene product or labeled protein at endogenous levels that can used to monitor various flagellar and basal body phenotypes. Mutants that show rescue and ones that fail to show rescue are both informative about the nature of the flagella and basal body defects. When rescue occurs, it can be used to determine the mutant gene product and to follow the temporal and spatial patterns of flagellar assembly. This review describes many examples of insights into basal body and flagellar proteins' function and assembly that have been discovered using dikaryons and discusses the potential for further analyses.
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Affiliation(s)
- Susan K Dutcher
- Department of Genetics, Washington University School of Medicine, St. Louis, Missouri
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82
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O'Toole ET, Dutcher SK. Site-specific basal body duplication in Chlamydomonas. Cytoskeleton (Hoboken) 2013; 71:108-18. [PMID: 24166861 DOI: 10.1002/cm.21155] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Revised: 10/16/2013] [Accepted: 10/22/2013] [Indexed: 11/12/2022]
Abstract
Correct centriole/basal body positioning is required for numerous biological processes, yet how the cell establishes this positioning is poorly understood. Analysis of centriolar/basal body duplication provides a key to understanding basal body positioning and function. Chlamydomonas basal bodies contain structural features that enable specific triplet microtubules to be specified. Electron tomography of cultures enriched in mitotic cells allowed us to follow basal body duplication and identify a specific triplet at which duplication occurs. Probasal bodies elongate in prophase, assemble transitional fibers (TF) and are segregated with a mature basal body near the poles of the mitotic spindle. A ring of nine-singlet microtubules is initiated at metaphase, orthogonal to triplet eight. At telophase/cytokinesis, triplet microtubule blades assemble first at the distal end, rather than at the proximal cartwheel. The cartwheel undergoes significant changes in length during duplication, which provides further support for its scaffolding role. The uni1-1 mutant contains short basal bodies with reduced or absent TF and defective transition zones, suggesting that the UNI1 gene product is important for coordinated probasal body elongation and maturation. We suggest that this site-specific basal body duplication ensures the correct positioning of the basal body to generate landmarks for intracellular patterning in the next generation.
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Affiliation(s)
- Eileen T O'Toole
- Department of Molecular, Cellular, and Developmental Biology, Boulder Laboratory for 3-D Electron Microscopy of Cells, University of Colorado, Boulder, Colorado
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Comartin D, Gupta G, Fussner E, Coyaud É, Hasegan M, Archinti M, Cheung S, Pinchev D, Lawo S, Raught B, Bazett-Jones DP, Lüders J, Pelletier L. CEP120 and SPICE1 Cooperate with CPAP in Centriole Elongation. Curr Biol 2013; 23:1360-6. [DOI: 10.1016/j.cub.2013.06.002] [Citation(s) in RCA: 122] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Revised: 05/06/2013] [Accepted: 06/03/2013] [Indexed: 11/27/2022]
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84
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Zanini C, Ercole E, Mandili G, Salaroli R, Poli A, Renna C, Papa V, Cenacchi G, Forni M. Medullospheres from DAOY, UW228 and ONS-76 cells: increased stem cell population and proteomic modifications. PLoS One 2013; 8:e63748. [PMID: 23717474 PMCID: PMC3663798 DOI: 10.1371/journal.pone.0063748] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Accepted: 04/05/2013] [Indexed: 12/18/2022] Open
Abstract
Background Medulloblastoma (MB) is an aggressive pediatric tumor of the Central Nervous System (CNS) usually treated according to a refined risk stratification. The study of cancer stem cells (CSC) in MB is a promising approach aimed at finding new treatment strategies. Methodology/Principal Findings The CSC compartment was studied in three characterized MB cell lines (DAOY, UW228 and ONS-76) grown in standard adhesion as well as being grown as spheres, which enables expansion of the CSC population. MB cell lines, grown in adherence and as spheres, were subjected to morphologic analysis at the light and electron microscopic level, as well as cytofluorimetric determinations. Medullospheres (MBS) were shown to express increasingly immature features, along with the stem cells markers: CD133, Nestin and β-catenin. Proteomic analysis highlighted the differences between MB cell lines, demonstrating a unique protein profile for each cell line, and minor differences when grown as spheres. In MBS, MALDI-TOF also identified some proteins, that have been linked to tumor progression and resistance, such as Nucleophosmin (NPM). In addition, immunocytochemistry detected Sox-2 as a stemness marker of MBS, as well as confirming high NPM expression. Conclusions/Significance Culture conditioning based on low attachment flasks and specialized medium may provide new data on the staminal compartment of CNS tumors, although a proteomic profile of CSC is still elusive for MB.
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Affiliation(s)
- Cristina Zanini
- EuroClone S.p.A Research Laboratory, Molecular Biotechnology Centre-MBC, University of Turin, Turin, Italy.
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85
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Ross I, Clarissa C, Giddings TH, Winey M. ε-tubulin is essential in Tetrahymena thermophila for the assembly and stability of basal bodies. J Cell Sci 2013; 126:3441-51. [PMID: 23704354 DOI: 10.1242/jcs.128694] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Basal bodies and centrioles are conserved microtubule-based organelles the improper assembly of which leads to a number of diseases, including ciliopathies and cancer. Tubulin family members are conserved components of these structures that are integral to their proper formation and function. We have identified the ε-tubulin gene in Tetrahymena thermophila and detected the protein, through fluorescence of a tagged allele, to basal bodies. Immunoelectron microscopy has shown that ε-tubulin localizes primarily to the core microtubule scaffold. A complete genomic knockout of ε-tubulin has revealed that it is an essential gene required for the assembly and maintenance of the triplet microtubule blades of basal bodies. We have conducted site-directed mutagenesis of the ε-tubulin gene and shown that residues within the nucleotide-binding domain, longitudinal interacting domains, and C-terminal tail are required for proper function. A single amino acid change of Thr150, a conserved residue in the nucleotide-binding domain, to Val is a conditional mutation that results in defects in the spatial and temporal assembly of basal bodies as well as their stability. We have genetically separated functions for the domains of ε-tubulin and identified a novel role for the nucleotide-binding domain in the regulation of basal body assembly and stability.
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Affiliation(s)
- Ian Ross
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado-Boulder, Boulder, CO 80309, USA
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86
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Stemm-Wolf AJ, Meehl JB, Winey M. Sfr13, a member of a large family of asymmetrically localized Sfi1-repeat proteins, is important for basal body separation and stability in Tetrahymena thermophila. J Cell Sci 2013; 126:1659-71. [PMID: 23426847 DOI: 10.1242/jcs.120238] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Directed fluid flow, which is achieved by the coordinated beating of motile cilia, is required for processes as diverse as cellular swimming, developmental patterning and mucus clearance. Cilia are nucleated, anchored and aligned at the plasma membrane by basal bodies, which are cylindrical microtubule-based structures with ninefold radial symmetry. In the unicellular ciliate Tetrahymena thermophila, two centrin family members associated with the basal body are important for both basal body organization and stabilization. We have identified a family of 13 proteins in Tetrahymena that contain centrin-binding repeats related to those identified in the Saccharomyces cerevisiae Sfi1 protein. We have named these proteins Sfr1-Sfr13 (for Sfi1-repeat). Nine of the Sfr proteins localize in unique polarized patterns surrounding the basal body, suggesting non-identical roles in basal body organization and association with basal body accessory structures. Furthermore, the Sfr proteins are found in distinct basal body populations in Tetrahymena cells, indicating that they are responsive to particular developmental programs. A complete genetic deletion of one of the family members, Sfr13, causes unstable basal bodies and defects in daughter basal body separation from the mother, phenotypes also observed with centrin disruption. It is likely that the other Sfr family members are involved in distinct centrin functions, providing specificity to the tasks that centrins perform at basal bodies.
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Affiliation(s)
- Alexander J Stemm-Wolf
- Department of Molecular, Cellular and Developmental Biology, University of Colorado - Boulder, Boulder, CO 80309, USA
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87
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Chen J, Meng Y, Zhou J, Zhuo M, Ling F, Zhang Y, Du H, Wang X. Identifying candidate genes for Type 2 Diabetes Mellitus and obesity through gene expression profiling in multiple tissues or cells. J Diabetes Res 2013; 2013:970435. [PMID: 24455749 PMCID: PMC3888709 DOI: 10.1155/2013/970435] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Revised: 09/30/2013] [Accepted: 10/25/2013] [Indexed: 12/18/2022] Open
Abstract
Type 2 Diabetes Mellitus (T2DM) and obesity have become increasingly prevalent in recent years. Recent studies have focused on identifying causal variations or candidate genes for obesity and T2DM via analysis of expression quantitative trait loci (eQTL) within a single tissue. T2DM and obesity are affected by comprehensive sets of genes in multiple tissues. In the current study, gene expression levels in multiple human tissues from GEO datasets were analyzed, and 21 candidate genes displaying high percentages of differential expression were filtered out. Specifically, DENND1B, LYN, MRPL30, POC1B, PRKCB, RP4-655J12.3, HIBADH, and TMBIM4 were identified from the T2DM-control study, and BCAT1, BMP2K, CSRNP2, MYNN, NCKAP5L, SAP30BP, SLC35B4, SP1, BAP1, GRB14, HSP90AB1, ITGA5, and TOMM5 were identified from the obesity-control study. The majority of these genes are known to be involved in T2DM and obesity. Therefore, analysis of gene expression in various tissues using GEO datasets may be an effective and feasible method to determine novel or causal genes associated with T2DM and obesity.
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Affiliation(s)
- Junhui Chen
- School of Bioscience and Bioengineering, Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou 510006, China
| | - Yuhuan Meng
- School of Bioscience and Bioengineering, Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou 510006, China
- Chinese PLA General Hospital, Beijing 100853, China
| | - Jinghui Zhou
- School of Bioscience and Bioengineering, Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou 510006, China
| | - Min Zhuo
- School of Bioscience and Bioengineering, Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou 510006, China
| | - Fei Ling
- School of Bioscience and Bioengineering, Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou 510006, China
| | - Yu Zhang
- Guangdong Laboratory Animals Monitoring Institute, Guangzhou 510555, China
| | - Hongli Du
- School of Bioscience and Bioengineering, Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou 510006, China
- *Hongli Du:
| | - Xiaoning Wang
- School of Bioscience and Bioengineering, Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou 510006, China
- Chinese PLA General Hospital, Beijing 100853, China
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88
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Bayless BA, Giddings TH, Winey M, Pearson CG. Bld10/Cep135 stabilizes basal bodies to resist cilia-generated forces. Mol Biol Cell 2012; 23:4820-32. [PMID: 23115304 PMCID: PMC3521689 DOI: 10.1091/mbc.e12-08-0577] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2012] [Revised: 10/18/2012] [Accepted: 10/23/2012] [Indexed: 12/03/2022] Open
Abstract
Basal bodies nucleate, anchor, and organize cilia. As the anchor for motile cilia, basal bodies must be resistant to the forces directed toward the cell as a consequence of ciliary beating. The molecules and generalized mechanisms that contribute to the maintenance of basal bodies remain to be discovered. Bld10/Cep135 is a basal body outer cartwheel domain protein that has established roles in the assembly of nascent basal bodies. We find that Bld10 protein first incorporates stably at basal bodies early during new assembly. Bld10 protein continues to accumulate at basal bodies after assembly, and we hypothesize that the full complement of Bld10 is required to stabilize basal bodies. We identify a novel mechanism for Bld10/Cep135 in basal body maintenance so that basal bodies can withstand the forces produced by motile cilia. Bld10 stabilizes basal bodies by promoting the stability of the A- and C-tubules of the basal body triplet microtubules and by properly positioning the triplet microtubule blades. The forces generated by ciliary beating promote basal body disassembly in bld10Δ cells. Thus Bld10/Cep135 acts to maintain the structural integrity of basal bodies against the forces of ciliary beating in addition to its separable role in basal body assembly.
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Affiliation(s)
- Brian A. Bayless
- Department of Cell and Developmental Biology, University of Colorado Denver–Anshutz Medical Campus, Aurora, CO 80045-2537
| | - Thomas H. Giddings
- Molecular, Cellular, and Developmental Biology, University of Colorado at Boulder, Boulder, CO 80309-0347
| | - Mark Winey
- Molecular, Cellular, and Developmental Biology, University of Colorado at Boulder, Boulder, CO 80309-0347
| | - Chad G. Pearson
- Department of Cell and Developmental Biology, University of Colorado Denver–Anshutz Medical Campus, Aurora, CO 80045-2537
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89
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Venoux M, Tait X, Hames RS, Straatman KR, Woodland HR, Fry AM. Poc1A and Poc1B act together in human cells to ensure centriole integrity. J Cell Sci 2012; 126:163-75. [PMID: 23015594 DOI: 10.1242/jcs.111203] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Proteomic studies in unicellular eukaryotes identified a set of centriolar proteins that included proteome of centriole 1 (Poc1). Functional studies in these organisms implicated Poc1 in centriole duplication and length control, as well as ciliogenesis. Using isoform-specific antibodies and RNAi depletion, we have examined the function of the two related human proteins, Poc1A and Poc1B. We find that Poc1A and Poc1B each localize to centrioles and spindle poles, but do so independently and with different dynamics. However, although loss of one or other Poc1 protein does not obviously disrupt mitosis, depletion of both proteins leads to defects in spindle organization with the generation of unequal or monopolar spindles. Our data indicate that, once incorporated, a fraction of Poc1A and Poc1B remains stably associated with parental centrioles, but that depletion prevents incorporation into nascent centrioles. Nascent centrioles lacking both Poc1A and Poc1B exhibit loss of integrity and maturation, and fail to undergo duplication. Thus, when Poc1A and Poc1B are co-depleted, new centrosomes capable of maturation cannot assemble and unequal spindles result. Interestingly, Poc1B, but not Poc1A, is phosphorylated in mitosis, and depletion of Poc1B alone was sufficient to perturb cell proliferation. Hence, Poc1A and Poc1B play redundant, but essential, roles in generation of stable centrioles, but Poc1B may have additional independent functions during cell cycle progression.
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Affiliation(s)
- Magali Venoux
- Department of Biochemistry, University of Leicester, Lancaster Road, Leicester LE1 9HN, UK
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90
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POC1A truncation mutation causes a ciliopathy in humans characterized by primordial dwarfism. Am J Hum Genet 2012; 91:330-6. [PMID: 22840364 DOI: 10.1016/j.ajhg.2012.05.025] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2012] [Revised: 04/08/2012] [Accepted: 05/30/2012] [Indexed: 11/21/2022] Open
Abstract
Primordial dwarfism (PD) is a phenotype characterized by profound growth retardation that is prenatal in onset. Significant strides have been made in the last few years toward improved understanding of the molecular underpinning of the limited growth that characterizes the embryonic and postnatal development of PD individuals. These include impaired mitotic mechanics, abnormal IGF2 expression, perturbed DNA-damage response, defective spliceosomal machinery, and abnormal replication licensing. In three families affected by a distinct form of PD, we identified a founder truncating mutation in POC1A. This gene is one of two vertebrate paralogs of POC1, which encodes one of the most abundant proteins in the Chlamydomonas centriole proteome. Cells derived from the index individual have abnormal mitotic mechanics with multipolar spindles, in addition to clearly impaired ciliogenesis. siRNA knockdown of POC1A in fibroblast cells recapitulates this ciliogenesis defect. Our findings highlight a human ciliopathy syndrome caused by deficiency of a major centriolar protein.
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91
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Sarig O, Nahum S, Rapaport D, Ishida-Yamamoto A, Fuchs-Telem D, Qiaoli L, Cohen-Katsenelson K, Spiegel R, Nousbeck J, Israeli S, Borochowitz ZU, Padalon-Brauch G, Uitto J, Horowitz M, Shalev S, Sprecher E. Short stature, onychodysplasia, facial dysmorphism, and hypotrichosis syndrome is caused by a POC1A mutation. Am J Hum Genet 2012; 91:337-42. [PMID: 22840363 DOI: 10.1016/j.ajhg.2012.06.003] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Revised: 05/24/2012] [Accepted: 06/05/2012] [Indexed: 11/26/2022] Open
Abstract
Disproportionate short stature refers to a heterogeneous group of hereditary disorders that are classified according to their mode of inheritance, clinical skeletal and nonskeletal manifestations, and radiological characteristics. In the present study, we report on an autosomal-recessive osteocutaneous disorder that we termed SOFT (short stature, onychodysplasia, facial dysmorphism, and hypotrichosis) syndrome. We employed homozygosity mapping to locate the disease-causing mutation to region 3p21.1-3p21.31. Using whole-exome-sequencing analysis complemented with Sanger direct sequencing of poorly covered regions, we identified a homozygous point mutation (c.512T>C [p.Leu171Pro]) in POC1A (centriolar protein homolog A). This mutation was found to cosegregate with the disease phenotype in two families. The p.Leu171Pro substitution affects a highly conserved amino acid residue and is predicted to interfere with protein function. Poc1, a POC1A ortholog, was previously found to have a role in centrosome stability in unicellular organisms. Accordingly, although centrosome structure was preserved, the number of centrosomes and their distribution were abnormal in affected cells. In addition, the Golgi apparatus presented a dispersed morphology, cholera-toxin trafficking from the plasma membrane to the Golgi was aberrant, and large vesicles accumulated in the cytosol. Collectively, our data underscore the importance of POC1A for proper bone, hair, and nail formation and highlight the importance of normal centrosomes in Golgi assembly and trafficking from the plasma membrane to the Golgi apparatus.
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92
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Abstract
The Saccharomyces cerevisiae mitotic spindle in budding yeast is exemplified by its simplicity and elegance. Microtubules are nucleated from a crystalline array of proteins organized in the nuclear envelope, known as the spindle pole body in yeast (analogous to the centrosome in larger eukaryotes). The spindle has two classes of nuclear microtubules: kinetochore microtubules and interpolar microtubules. One kinetochore microtubule attaches to a single centromere on each chromosome, while approximately four interpolar microtubules emanate from each pole and interdigitate with interpolar microtubules from the opposite spindle to provide stability to the bipolar spindle. On the cytoplasmic face, two to three microtubules extend from the spindle pole toward the cell cortex. Processes requiring microtubule function are limited to spindles in mitosis and to spindle orientation and nuclear positioning in the cytoplasm. Microtubule function is regulated in large part via products of the 6 kinesin gene family and the 1 cytoplasmic dynein gene. A single bipolar kinesin (Cin8, class Kin-5), together with a depolymerase (Kip3, class Kin-8) or minus-end-directed kinesin (Kar3, class Kin-14), can support spindle function and cell viability. The remarkable feature of yeast cells is that they can survive with microtubules and genes for just two motor proteins, thus providing an unparalleled system to dissect microtubule and motor function within the spindle machine.
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93
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Backer CB, Gutzman JH, Pearson CG, Cheeseman IM. CSAP localizes to polyglutamylated microtubules and promotes proper cilia function and zebrafish development. Mol Biol Cell 2012; 23:2122-30. [PMID: 22493317 PMCID: PMC3364176 DOI: 10.1091/mbc.e11-11-0931] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Subsets of microtubules are modified by polyglutamylation, but the precise function of this modification is unknown. A microtubule-binding protein, CSAP, is identified that colocalizes with polyglutamylated tubulin. In zebrafish, CSAP is required for normal brain development and proper left–right asymmetry. The diverse populations of microtubule polymers in cells are functionally distinguished by different posttranslational modifications, including polyglutamylation. Polyglutamylation is enriched on subsets of microtubules including those found in the centrioles, mitotic spindle, and cilia. However, whether this modification alters intrinsic microtubule dynamics or affects extrinsic associations with specific interacting partners remains to be determined. Here we identify the microtubule-binding protein centriole and spindle–associated protein (CSAP), which colocalizes with polyglutamylated tubulin to centrioles, spindle microtubules, and cilia in human tissue culture cells. Reducing tubulin polyglutamylation prevents CSAP localization to both spindle and cilia microtubules. In zebrafish, CSAP is required for normal brain development and proper left–right asymmetry, defects that are qualitatively similar to those reported previously for depletion of polyglutamylation-conjugating enzymes. We also find that CSAP is required for proper cilia beating. Our work supports a model in which polyglutamylation can target selected microtubule-associated proteins, such as CSAP, to microtubule subpopulations, providing specific functional capabilities to these populations.
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Affiliation(s)
- Chelsea B Backer
- Whitehead Institute for Biomedical Research and Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
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94
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Coon BG, Hernandez V, Madhivanan K, Mukherjee D, Hanna CB, Barinaga-Rementeria Ramirez I, Lowe M, Beales PL, Aguilar RC. The Lowe syndrome protein OCRL1 is involved in primary cilia assembly. Hum Mol Genet 2012; 21:1835-47. [DOI: 10.1093/hmg/ddr615] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
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95
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96
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Winey M, Stemm-Wolf AJ, Giddings TH, Pearson CG. Cytological analysis of Tetrahymena thermophila. Methods Cell Biol 2012; 109:357-78. [PMID: 22444152 DOI: 10.1016/b978-0-12-385967-9.00013-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Since their first detection in pond water, large ciliates such as Tetrahymena thermophila, have captivated school children and scientists alike with the elegance of their swimming and the beauty of their cortical organization. Indeed, cytology - simply looking at cells - is an important component of most areas of study in cell biology and is particularly intriguing in the large, complex Tetrahymena cell. Cytological analysis of Tetrahymena is critical for the study of the microtubule cytoskeleton, membrane trafficking, complex nuclear movements and interactions, and the cellular remodeling during conjugation, to name a few topics. We briefly review previously reported cytological techniques for both light and electron microscopy, and point the reader to resources to learn about those protocols. We go on to present new and emerging technologies for the study of these marvelous cells. These include the use of fluorescent-protein tagging to localize cellular components in live cells, as well as for tracking the dynamic behavior of proteins using pulse labeling and fluorescence recovery after photobleaching. For electron microscopy, cellular and antigenic preservation has been improved with the use of cryofixation and freeze-substitution. The technologies described here advance Tetrahymena cell biology to the cutting-edge of cytological analysis.
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Affiliation(s)
- Mark Winey
- MCD Biology, University of Colorado at Boulder, 347 UCB, Boulder, Colorado 80309-0347, USA
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97
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Wloga D, Frankel J. From Molecules to Morphology: Cellular Organization of Tetrahymena thermophila. Methods Cell Biol 2012; 109:83-140. [DOI: 10.1016/b978-0-12-385967-9.00005-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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98
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Vincensini L, Blisnick T, Bastin P. [The importance of model organisms to study cilia and flagella biology]. Biol Aujourdhui 2011; 205:5-28. [PMID: 21501571 DOI: 10.1051/jbio/2011005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2011] [Indexed: 12/24/2022]
Abstract
Cilia and flagella are ubiquitous organelles that protrude from the surfaces of many cells, and whose architecture is highly conserved from protists to humans. These complex organelles, composed of over 500 proteins, can be either immotile or motile. They are involved in a myriad of biological processes, including sensing (non-motile cilia) and/or cell motility or movement of extracellular fluids (motile cilia). The ever-expanding list of human diseases linked to defective cilia illustrates the functional importance of cilia and flagella. These ciliopathies are characterised by an impressive diversity of symptoms and an often complex genetic etiology. A precise knowledge of cilia and flagella biology is thus critical to better understand these pathologies. However, multi-ciliated cells are terminally differentiated and difficult to manipulate, and a primary cilium is assembled only when the cell exits from the cell cycle. In this context the use of model organisms, that relies on the high degree of structural but also of molecular conservation of these organelles across evolution, is instrumental to decipher the many facets of cilia and flagella biology. In this review, we highlight the specific strengths of the main model organisms to investigate the molecular composition, mode of assembly, sensing and motility mechanisms and functions of cilia and flagella. Pioneering studies carried out in the green alga Chlamydomonas established the link between cilia and several genetic diseases. Moreover, multicellular organisms such as mouse, zebrafish, Xenopus, C. elegans or Drosophila, and protists like Paramecium, Tetrahymena and Trypanosoma or Leishmania each bring specific advantages to the study of cilium biology. For example, the function of genes involved in primary ciliary dyskinesia (due to defects in ciliary motility) can be efficiently assessed in trypanosomes.
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Affiliation(s)
- Laetitia Vincensini
- Unité de Biologie Cellulaire des Trypanosomes, Institut Pasteur et CNRS URA 2581, 25 rue du Docteur Roux, 75724 Paris Cedex 15, France.
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Gogendeau D, Hurbain I, Raposo G, Cohen J, Koll F, Basto R. Sas-4 proteins are required during basal body duplication in Paramecium. Mol Biol Cell 2011; 22:1035-44. [PMID: 21289083 PMCID: PMC3069007 DOI: 10.1091/mbc.e10-11-0901] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
This study investigated the role of Sas-4 in basal body duplication in Paramecium and found that Sas-4 proteins are required to assemble and stabilize the germinative disk and cartwheel, which suggests that Sas-4 plays an essential role in basal body duplication. Centrioles and basal bodies are structurally related organelles composed of nine microtubule (MT) triplets. Studies performed in Caenorhabditis elegans embryos have shown that centriole duplication takes place in sequential way, in which different proteins are recruited in a specific order to assemble a procentriole. ZYG-1 initiates centriole duplication by triggering the recruitment of a complex of SAS-5 and SAS-6, which then recruits the final player, SAS-4, to allow the incorporation of MT singlets. It is thought that a similar mechanism (that also involves additional proteins) is present in other animal cells, but it remains to be investigated whether the same players and their ascribed functions are conserved during basal body duplication in cells that exclusively contain basal bodies. To investigate this question, we have used the multiciliated protist Paramecium tetraurelia. Here we show that in the absence of PtSas4, two types of defects in basal body duplication can be identified. In the majority of cases, the germinative disk and cartwheel, the first structures assembled during duplication, are not detected. In addition, if daughter basal bodies were formed, they invariably had defects in MT recruitment. Our results suggest that PtSas4 has a broader function than its animal orthologues.
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100
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Abstract
Centrioles are conserved microtubule-based organelles that lie at the core of the animal centrosome and play a crucial role in nucleating the formation of cilia and flagella in most eukaryotes. Centrioles have a complex ultrastructure with ninefold symmetry and a well-defined length. This structure is assembled from a host of proteins, including a variety of disease gene products. Over a century after the discovery of centrioles, the mechanisms underlying the assembly of these fascinating organelles, in particular the establishment of ninefold symmetry and the control of centriole length, are now starting to be uncovered.
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Affiliation(s)
- Juliette Azimzadeh
- Department of Biochemistry and Biophysics, University of California, San Francisco, 94143, USA
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