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Hilgendorf KI, Myers BR, Reiter JF. Emerging mechanistic understanding of cilia function in cellular signalling. Nat Rev Mol Cell Biol 2024; 25:555-573. [PMID: 38366037 PMCID: PMC11199107 DOI: 10.1038/s41580-023-00698-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/21/2023] [Indexed: 02/18/2024]
Abstract
Primary cilia are solitary, immotile sensory organelles present on most cells in the body that participate broadly in human health, physiology and disease. Cilia generate a unique environment for signal transduction with tight control of protein, lipid and second messenger concentrations within a relatively small compartment, enabling reception, transmission and integration of biological information. In this Review, we discuss how cilia function as signalling hubs in cell-cell communication using three signalling pathways as examples: ciliary G-protein-coupled receptors (GPCRs), the Hedgehog (Hh) pathway and polycystin ion channels. We review how defects in these ciliary signalling pathways lead to a heterogeneous group of conditions known as 'ciliopathies', including metabolic syndromes, birth defects and polycystic kidney disease. Emerging understanding of these pathways' transduction mechanisms reveals common themes between these cilia-based signalling pathways that may apply to other pathways as well. These mechanistic insights reveal how cilia orchestrate normal and pathophysiological signalling outputs broadly throughout human biology.
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Affiliation(s)
- Keren I Hilgendorf
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT, USA.
| | - Benjamin R Myers
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT, USA.
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, UT, USA.
- Department of Bioengineering, University of Utah School of Medicine, Salt Lake City, UT, USA.
| | - Jeremy F Reiter
- Department of Biochemistry and Biophysics, Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA, USA.
- Chan Zuckerberg Biohub, San Francisco, CA, USA.
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2
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Curinha A, Huang Z, Anglen T, Strong MA, Gliech CR, Jewett CE, Friskes A, Holland AJ. Centriole structural integrity defects are a crucial feature of Hydrolethalus Syndrome. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.06.583733. [PMID: 38496445 PMCID: PMC10942441 DOI: 10.1101/2024.03.06.583733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
Hydrolethalus Syndrome (HLS) is a lethal, autosomal recessive ciliopathy caused by the mutation of the conserved centriole protein HYLS1. However, how HYLS1 facilitates the centriole-based templating of cilia is poorly understood. Here, we show that mice harboring the HYLS1 disease mutation die shortly after birth and exhibit developmental defects that recapitulate several manifestations of the human disease. These phenotypes arise from tissue-specific defects in cilia assembly and function caused by a loss of centriole integrity. We show that HYLS1 is recruited to the centriole by CEP120 and functions to recruit centriole inner scaffold proteins that stabilize the centriolar microtubule wall. The HLS mutation disrupts the interaction of HYLS1 with CEP120 leading to HYLS1 displacement and degeneration of the centriole distal end. We propose that tissue-specific defects in centriole integrity caused by the HYLS1 mutation prevent ciliogenesis and drive HLS phenotypes.
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Affiliation(s)
- Ana Curinha
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Zhaoyu Huang
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Taylor Anglen
- Department of Biomedical Engineering, Duke University, Durham, NC, USA
| | - Margaret A Strong
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Colin R Gliech
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Cayla E Jewett
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Anoek Friskes
- Division of Cell Biology, Oncode Institute, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Andrew J Holland
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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3
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Pierron M, Woglar A, Busso C, Jha K, Mikeladze‐Dvali T, Croisier M, Gönczy P. Centriole elimination during Caenorhabditis elegans oogenesis initiates with loss of the central tube protein SAS-1. EMBO J 2023; 42:e115076. [PMID: 37987153 PMCID: PMC10711648 DOI: 10.15252/embj.2023115076] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2023] [Revised: 10/23/2023] [Accepted: 10/24/2023] [Indexed: 11/22/2023] Open
Abstract
In most metazoans, centrioles are lost during oogenesis, ensuring that the zygote is endowed with the correct number of two centrioles, which are paternally contributed. How centriole architecture is dismantled during oogenesis is not understood. Here, we analyze with unprecedent detail the ultrastructural and molecular changes during oogenesis centriole elimination in Caenorhabditis elegans. Centriole elimination begins with loss of the so-called central tube and organelle widening, followed by microtubule disassembly. The resulting cluster of centriolar proteins then disappears gradually, usually moving in a microtubule- and dynein-dependent manner to the plasma membrane. Our analysis indicates that neither Polo-like kinases nor the PCM, which modulate oogenesis centriole elimination in Drosophila, do so in C. elegans. Furthermore, we demonstrate that the central tube protein SAS-1 normally departs initially from the organelle, which loses integrity earlier in sas-1 mutants. Overall, our work provides novel mechanistic insights regarding the fundamental process of oogenesis centriole elimination.
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Affiliation(s)
- Marie Pierron
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life SciencesSwiss Federal Institute of Technology Lausanne (EPFL)LausanneSwitzerland
| | - Alexander Woglar
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life SciencesSwiss Federal Institute of Technology Lausanne (EPFL)LausanneSwitzerland
| | - Coralie Busso
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life SciencesSwiss Federal Institute of Technology Lausanne (EPFL)LausanneSwitzerland
| | - Keshav Jha
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life SciencesSwiss Federal Institute of Technology Lausanne (EPFL)LausanneSwitzerland
| | | | - Marie Croisier
- BIO‐EM platform, School of Life SciencesSwiss Federal Institute of Technology Lausanne (EPFL)LausanneSwitzerland
| | - Pierre Gönczy
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life SciencesSwiss Federal Institute of Technology Lausanne (EPFL)LausanneSwitzerland
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4
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Kalbfuss N, Gönczy P. Towards understanding centriole elimination. Open Biol 2023; 13:230222. [PMID: 37963546 PMCID: PMC10645514 DOI: 10.1098/rsob.230222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 09/14/2023] [Indexed: 11/16/2023] Open
Abstract
Centrioles are microtubule-based structures crucial for forming flagella, cilia and centrosomes. Through these roles, centrioles are critical notably for proper cell motility, signalling and division. Recent years have advanced significantly our understanding of the mechanisms governing centriole assembly and architecture. Although centrioles are typically very stable organelles, persisting over many cell cycles, they can also be eliminated in some cases. Here, we review instances of centriole elimination in a range of species and cell types. Moreover, we discuss potential mechanisms that enable the switch from a stable organelle to a vanishing one. Further work is expected to provide novel insights into centriole elimination mechanisms in health and disease, thereby also enabling scientists to readily manipulate organelle fate.
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Affiliation(s)
- Nils Kalbfuss
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Pierre Gönczy
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), 1015 Lausanne, Switzerland
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5
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Campagna CM, McMahon H, Nechipurenko I. The G protein alpha chaperone and guanine-nucleotide exchange factor RIC-8 regulates cilia morphogenesis in Caenorhabditis elegans sensory neurons. PLoS Genet 2023; 19:e1011015. [PMID: 37910589 PMCID: PMC10642896 DOI: 10.1371/journal.pgen.1011015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2023] [Revised: 11/13/2023] [Accepted: 10/12/2023] [Indexed: 11/03/2023] Open
Abstract
Heterotrimeric G (αβγ) proteins are canonical transducers of G-protein-coupled receptor (GPCR) signaling and play critical roles in communication between cells and their environment. Many GPCRs and heterotrimeric G proteins localize to primary cilia and modulate cilia morphology via mechanisms that are not well understood. Here, we show that RIC-8, a cytosolic guanine nucleotide exchange factor (GEF) and chaperone for Gα protein subunits, shapes cilia membrane morphology in a subset of Caenorhabditis elegans sensory neurons. Consistent with its role in ciliogenesis, C. elegans RIC-8 localizes to cilia in different sensory neuron types. Using domain mutagenesis, we demonstrate that while the GEF function alone is not sufficient, both the GEF and Gα-interacting chaperone motifs of RIC-8 are required for its role in cilia morphogenesis. We identify ODR-3 as the RIC-8 Gα client and demonstrate that RIC-8 functions in the same genetic pathway with another component of the non-canonical G protein signaling AGS-3 to shape cilia morphology. Notably, despite defects in AWC cilia morphology, ags-3 null mutants exhibit normal chemotaxis toward benzaldehyde unlike odr-3 mutant animals. Collectively, our findings describe a novel function for the evolutionarily conserved protein RIC-8 and non-canonical RIC-8-AGS-3-ODR-3 signaling in cilia morphogenesis and uncouple Gα ODR-3 functions in ciliogenesis and olfaction.
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Affiliation(s)
- Christina M. Campagna
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, Massachusetts, United States of America
| | - Hayley McMahon
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, Massachusetts, United States of America
| | - Inna Nechipurenko
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, Massachusetts, United States of America
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6
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Kalbfuss N, Berger A, Gönczy P. Mapping of centriolar proteins onto the post-embryonic lineage of C. elegans. Dev Biol 2023; 502:68-76. [PMID: 37414202 DOI: 10.1016/j.ydbio.2023.07.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 06/22/2023] [Accepted: 07/03/2023] [Indexed: 07/08/2023]
Abstract
Centrioles, together with the surrounding peri-centriolar material (PCM), constitute the centrosome, a major microtubule-organizing center of animal cells. Despite being critical in many cells for signaling, motility and division, centrioles can be eliminated in some systems, including in the vast majority of differentiating cells during embryogenesis in Caenorhabditis elegans. Whether the cells retaining centrioles in the resulting L1 larvae do so because they lack an activity that eliminates centrioles in the other cells is not known. Moreover, the extent to which centrioles and PCM remain present in later stages of worm development, when all cells but those of the germ line are terminally differentiated, is not known. Here, by fusing cells that lack centrioles with cells that retain them, we established that L1 larvae do not possess a diffusible elimination activity sufficient to remove centrioles. Moreover, analyzing PCM core proteins in L1 larval cells that retain centrioles, we found that some such proteins, but not all, are present as well. Furthermore, we uncovered that foci of centriolar proteins remain present in specific terminally differentiated cells of adult hermaphrodites and males, in particular in the somatic gonad. Correlating the time at which cells were born with the fate of their centrioles revealed that it is not cell age, but instead cell fate, that determines whether and when centrioles are eliminated. Overall, our work maps the localization of centriolar and PCM core proteins in the post-embryonic C. elegans lineage, thereby providing an essential blueprint for uncovering mechanisms modulating their presence and function.
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Affiliation(s)
- Nils Kalbfuss
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), Lausanne, CH-1015, Switzerland
| | - Antonin Berger
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), Lausanne, CH-1015, Switzerland
| | - Pierre Gönczy
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), Lausanne, CH-1015, Switzerland.
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7
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Campagna CM, McMahon H, Nechipurenko I. The G protein alpha Chaperone and Guanine-Nucleotide Exchange Factor RIC-8 Regulates Cilia Morphogenesis in Caenorhabditis elegans Sensory Neurons. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.25.554856. [PMID: 37662329 PMCID: PMC10473713 DOI: 10.1101/2023.08.25.554856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/05/2023]
Abstract
Heterotrimeric G (αβγ) proteins are canonical transducers of G-protein-coupled receptor (GPCR) signaling and play critical roles in communication between cells and their environment. Many GPCRs and heterotrimeric G proteins localize to primary cilia and modulate cilia morphology via mechanisms that are not well understood. Here, we show that RIC-8, a cytosolic guanine nucleotide exchange factor (GEF) and chaperone for Gα protein subunits, shapes cilia membrane morphology in a subset of Caenorhabditis elegans sensory neurons. Consistent with its role in ciliogenesis, C. elegans RIC-8 localizes to cilia in different sensory neuron types. Using domain mutagenesis, we demonstrate that while the GEF function alone is not sufficient, both the GEF and Gα-interacting chaperone motifs of RIC-8 are required for its role in cilia morphogenesis. We identify ODR-3 as the RIC-8 Gα client and demonstrate that RIC-8 functions in the same genetic pathway with another component of the non-canonical G protein signaling AGS-3 to shape cilia morphology. Notably, despite severe defects in AWC cilia morphology, ags-3 null mutants exhibit normal chemotaxis toward benzaldehyde unlike odr-3 mutant animals. Collectively, our findings describe a novel function for the evolutionarily conserved protein RIC-8 and non-canonical RIC-8-AGS-3-ODR-3 signaling in cilia morphogenesis and uncouple Gα ODR-3 functions in ciliogenesis and olfaction.
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Affiliation(s)
- Christina M. Campagna
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, Massachusetts, United States of America
| | - Hayley McMahon
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, Massachusetts, United States of America
| | - Inna Nechipurenko
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, Massachusetts, United States of America
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8
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Dobbelaere J, Su TY, Erdi B, Schleiffer A, Dammermann A. A phylogenetic profiling approach identifies novel ciliogenesis genes in Drosophila and C. elegans. EMBO J 2023; 42:e113616. [PMID: 37317646 PMCID: PMC10425847 DOI: 10.15252/embj.2023113616] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 05/22/2023] [Accepted: 06/01/2023] [Indexed: 06/16/2023] Open
Abstract
Cilia are cellular projections that perform sensory and motile functions in eukaryotic cells. A defining feature of cilia is that they are evolutionarily ancient, yet not universally conserved. In this study, we have used the resulting presence and absence pattern in the genomes of diverse eukaryotes to identify a set of 386 human genes associated with cilium assembly or motility. Comprehensive tissue-specific RNAi in Drosophila and mutant analysis in C. elegans revealed signature ciliary defects for 70-80% of novel genes, a percentage similar to that for known genes within the cluster. Further characterization identified different phenotypic classes, including a set of genes related to the cartwheel component Bld10/CEP135 and two highly conserved regulators of cilium biogenesis. We propose this dataset defines the core set of genes required for cilium assembly and motility across eukaryotes and presents a valuable resource for future studies of cilium biology and associated disorders.
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Affiliation(s)
- Jeroen Dobbelaere
- Max Perutz LabsUniversity of Vienna, Vienna Biocenter (VBC)ViennaAustria
| | - Tiffany Y Su
- Max Perutz LabsUniversity of Vienna, Vienna Biocenter (VBC)ViennaAustria
- Vienna BioCenter PhD ProgramDoctoral School of the University of Vienna and Medical University of ViennaViennaAustria
| | - Balazs Erdi
- Max Perutz LabsUniversity of Vienna, Vienna Biocenter (VBC)ViennaAustria
| | - Alexander Schleiffer
- Research Institute of Molecular Pathology, Vienna Biocenter (VBC)ViennaAustria
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Vienna Biocenter (VBC)ViennaAustria
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9
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Bergwell M, Smith A, Smith E, Dierlam C, Duran R, Haastrup E, Napier-Jameson R, Seidel R, Potter W, Norris A, Iyer J. A primary microcephaly-associated sas-6 mutation perturbs centrosome duplication, dendrite morphogenesis, and ciliogenesis in Caenorhabditis elegans. Genetics 2023; 224:iyad105. [PMID: 37279547 PMCID: PMC10411591 DOI: 10.1093/genetics/iyad105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 05/23/2023] [Accepted: 05/24/2023] [Indexed: 06/08/2023] Open
Abstract
The human SASS6(I62T) missense mutation has been linked with the incidence of primary microcephaly in a Pakistani family, although the mechanisms by which this mutation causes disease remain unclear. The SASS6(I62T) mutation corresponds to SAS-6(L69T) in Caenorhabditis elegans. Given that SAS-6 is highly conserved, we modeled this mutation in C. elegans and examined the sas-6(L69T) effect on centrosome duplication, ciliogenesis, and dendrite morphogenesis. Our studies revealed that all the above processes are perturbed by the sas-6(L69T) mutation. Specifically, C. elegans carrying the sas-6(L69T) mutation exhibit an increased failure of centrosome duplication in a sensitized genetic background. Further, worms carrying this mutation also display shortened phasmid cilia, an abnormal phasmid cilia morphology, shorter phasmid dendrites, and chemotaxis defects. Our data show that the centrosome duplication defects caused by this mutation are only uncovered in a sensitized genetic background, indicating that these defects are mild. However, the ciliogenesis and dendritic defects caused by this mutation are evident in an otherwise wild-type background, indicating that they are stronger defects. Thus, our studies shed light on the novel mechanisms by which the sas-6(L69T) mutation could contribute to the incidence of primary microcephaly in humans.
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Affiliation(s)
- Mary Bergwell
- Oklahoma Medical Research Foundation, Cell Cycle & Cancer Biology Research Program, Oklahoma City, OK 73104, USA
| | - Amy Smith
- Pfizer Inc., Pharmaceutical R&D – Drug Product Design & Development, Chesterfield, MO 63017, USA
| | - Ellie Smith
- University of Tulsa, Department of Chemistry and Biochemistry, Tulsa, OK 74104, USA
| | - Carter Dierlam
- University of Tulsa, Department of Chemistry and Biochemistry, Tulsa, OK 74104, USA
| | - Ramon Duran
- University of Tulsa, Department of Chemistry and Biochemistry, Tulsa, OK 74104, USA
| | - Erin Haastrup
- University of Tulsa, Department of Chemistry and Biochemistry, Tulsa, OK 74104, USA
| | | | - Rory Seidel
- University of Tulsa, Department of Chemistry and Biochemistry, Tulsa, OK 74104, USA
| | - William Potter
- University of Tulsa, Department of Chemistry and Biochemistry, Tulsa, OK 74104, USA
| | - Adam Norris
- Southern Methodist University, Department of Biological Sciences, Dallas, TX 75275, USA
| | - Jyoti Iyer
- University of Tulsa, Department of Chemistry and Biochemistry, Tulsa, OK 74104, USA
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10
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Kalbfuss N, Gönczy P. Extensive programmed centriole elimination unveiled in C. elegans embryos. SCIENCE ADVANCES 2023; 9:eadg8682. [PMID: 37256957 PMCID: PMC10413642 DOI: 10.1126/sciadv.adg8682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 04/25/2023] [Indexed: 06/02/2023]
Abstract
Centrioles are critical for fundamental cellular processes, including signaling, motility, and division. The extent to which centrioles are present after cell cycle exit in a developing organism is not known. The stereotypical lineage of Caenorhabditis elegans makes it uniquely well-suited to investigate this question. Using notably lattice light-sheet microscopy, correlative light electron microscopy, and lineage assignment, we found that ~88% of cells lose centrioles during embryogenesis. Our analysis reveals that centriole elimination is stereotyped, occurring invariably at a given time in a given cell type. Moreover, we established that experimentally altering cell fate results in corresponding changes in centriole fate. Overall, we uncovered the existence of an extensive centriole elimination program, which we anticipate to be paradigmatic for a broad understanding of centriole fate regulation.
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Affiliation(s)
- Nils Kalbfuss
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), CH-1015 Lausanne, Switzerland
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11
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Primary Cilia Are Frequently Present in Small Cell Lung Carcinomas but Not in Non–Small Cell Lung Carcinomas or Lung Carcinoids. J Transl Med 2023; 103:100007. [PMID: 37039149 DOI: 10.1016/j.labinv.2022.100007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 06/30/2022] [Accepted: 08/11/2022] [Indexed: 01/11/2023] Open
Abstract
Most human malignant neoplasms show loss of primary cilia (PC). However, PC are known to be retained and involved in tumorigenesis in some types of neoplasms. The PC status in lung carcinomas remains largely uninvestigated. In this study, we comprehensively assessed the PC status in lung carcinomas. A total of 492 lung carcinomas, consisting of adenocarcinomas (ACs) (n = 319), squamous cell carcinomas (SCCs) (n = 152), and small cell lung carcinomas (SCLCs) (n = 21), were examined by immunohistochemical analysis using an antibody against ARL13B, a marker of PC. The PC-positive rate was markedly higher in SCLCs (81.0%) than in ACs (1.6%) and SCCs (7.9%). We subsequently performed analyses to characterize the PC-positive lung carcinomas further. PC-positive lung carcinomas were more numerous and had longer PC than normal cells. The presence of PC in these cells was not associated with the phase of the cell cycle. We also found that the PC were retained even in metastases from PC-positive lung carcinomas. Furthermore, the hedgehog signaling pathway was activated in PC-positive lung carcinomas. Because ARL13B immunohistochemistry of lung carcinoids (n = 10) also showed a statistically significantly lower rate (10.0%) of PC positivity than SCLCs, we searched for a gene(s) that might be upregulated in PC-positive SCLCs compared with lung carcinoids, but not in PC-negative carcinomas. This search, and further cell culture experiments, identified HYLS1 as a gene possessing the ability to regulate ciliogenesis in PC-positive lung carcinomas. In conclusion, our findings indicate that PC are frequently present in SCLCs but not in non-SCLCs (ACs and SCCs) or lung carcinoids, and their PC exhibit various specific pathobiological characteristics. This suggests an important link between lung carcinogenesis and PC.
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12
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Maurya AK. Structural diversity in a stereotypic organelle - Sensory cilia of Caenorhabditis elegans. J Cell Physiol 2022; 237:2668-2672. [PMID: 35686462 DOI: 10.1002/jcp.30732] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 02/25/2022] [Accepted: 03/21/2022] [Indexed: 11/07/2022]
Abstract
Sensory cilia, an ancient organelle, displays a high degree of conservation in its structure and functioning. Sensory cilia also fulfill a wide range of sensory functions, from sensing environmental signals (light, sound, chemicals, and mechanical forces) to interpreting intercellular developmental signals. One way they appear to fulfill these diverse and specialized roles is by adopting a variety of shapes and sizes. We are only beginning to document and appreciate this complexity. Here in this review, using the varied and specialized cilia found on Caenorhabditis elegans sensory neurons, I highlight some of the most obvious examples of this structural diversity and the underlying mechanisms if known. Such structural diversity appears to arise from the modulation of deeply conserved molecular pathways and also from cell- and species-specific mechanisms. Studying these ciliary specializations will thus provide for a comprehensive understanding of ciliary biology and might uncover understudied aspects of ciliary disease biology.
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Affiliation(s)
- Ashish K Maurya
- Department of Biology, Brandeis University, Waltham, Massachusetts, USA
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13
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Holzer E, Rumpf-Kienzl C, Falk S, Dammermann A. A modified TurboID approach identifies tissue-specific centriolar components in C. elegans. PLoS Genet 2022; 18:e1010150. [PMID: 35442950 PMCID: PMC9020716 DOI: 10.1371/journal.pgen.1010150] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 03/15/2022] [Indexed: 01/26/2023] Open
Abstract
Proximity-dependent labeling approaches such as BioID have been a great boon to studies of protein-protein interactions in the context of cytoskeletal structures such as centrosomes which are poorly amenable to traditional biochemical approaches like immunoprecipitation and tandem affinity purification. Yet, these methods have so far not been applied extensively to invertebrate experimental models such as C. elegans given the long labeling times required for the original promiscuous biotin ligase variant BirA*. Here, we show that the recently developed variant TurboID successfully probes the interactomes of both stably associated (SPD-5) and dynamically localized (PLK-1) centrosomal components. We further develop an indirect proximity labeling method employing a GFP nanobody-TurboID fusion, which allows the identification of protein interactors in a tissue-specific manner in the context of the whole animal. Critically, this approach utilizes available endogenous GFP fusions, avoiding the need to generate multiple additional strains for each target protein and the potential complications associated with overexpressing the protein from transgenes. Using this method, we identify homologs of two highly conserved centriolar components, Cep97 and BLD10/Cep135, which are present in various somatic tissues of the worm. Surprisingly, neither protein is expressed in early embryos, likely explaining why these proteins have escaped attention until now. Our work expands the experimental repertoire for C. elegans and opens the door for further studies of tissue-specific variation in centrosome architecture.
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Affiliation(s)
- Elisabeth Holzer
- Max Perutz Labs, University of Vienna, Vienna Biocenter (VBC), Vienna, Austria
| | | | - Sebastian Falk
- Max Perutz Labs, University of Vienna, Vienna Biocenter (VBC), Vienna, Austria
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14
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Abreu CMC, Dantas TJ. Coping with centriole loss: pericentriolar material maintenance after centriole degeneration. Commun Biol 2021; 4:705. [PMID: 34108611 PMCID: PMC8190072 DOI: 10.1038/s42003-021-02243-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Shortly after the onset of ciliogenesis in Caenorhabditis elegans sensory neurons, the centrioles/basal bodies undergo degeneration. The fate of the pericentriolar material (PCM) that was associated with those centrioles has, however, remained unknown. Two recent studies by the Dammermann and the Feldman groups now show that not only does the PCM persist at the ciliary base, it also continues to assemble in the absence of canonical centrioles. Importantly, these neuronal centrosomes retain the ability to function as the cell’s main microtubule-organizing center and support ciliary function.
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Affiliation(s)
- Carla M C Abreu
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal. .,IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal.
| | - Tiago J Dantas
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal. .,IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal.
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15
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Garbrecht J, Laos T, Holzer E, Dillinger M, Dammermann A. An acentriolar centrosome at the C. elegans ciliary base. Curr Biol 2021; 31:2418-2428.e8. [PMID: 33798427 DOI: 10.1016/j.cub.2021.03.023] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 01/13/2021] [Accepted: 03/05/2021] [Indexed: 01/26/2023]
Abstract
In animal cells, the functions of the microtubule cytoskeleton are coordinated by centriole-based centrosomes via γ-tubulin complexes embedded in the pericentriolar material or PCM.1 PCM assembly has been best studied in the context of mitosis, where centriolar SPD-2 recruits PLK-1, which in turn phosphorylates key scaffolding components like SPD-5 and CNN to promote expansion of the PCM polymer.2-4 To what extent these mechanisms apply to centrosomes in interphase or in differentiated cells remains unclear.5 Here, we examine a novel type of centrosome found at the ciliary base of C. elegans sensory neurons, which we show plays important roles in neuronal morphogenesis, cellular trafficking, and ciliogenesis. These centrosomes display similar dynamic behavior to canonical, mitotic centrosomes, with a stable PCM scaffold and dynamically localized client proteins. Unusually, however, they are not organized by centrioles, which degenerate early in terminal differentiation.6 Yet, PCM not only persists but continues to grow with key scaffolding proteins including SPD-5 expressed under control of the RFX transcription factor DAF-19. This assembly occurs in the absence of the mitotic regulators SPD-2, AIR-1 and PLK-1, but requires tethering by PCMD-1, a protein which also plays a role in the initial, interphase recruitment of PCM in early embryos.7 These results argue for distinct mechanisms for mitotic and non-mitotic PCM assembly, with only the former requiring PLK-1 phosphorylation to drive rapid expansion of the scaffold polymer.
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Affiliation(s)
- Joachim Garbrecht
- Max Perutz Labs, University of Vienna, Vienna Biocenter (VBC), Dr Bohr-Gasse 9, A-1030 Vienna, Austria; Vienna BioCenter PhD Program, Doctoral School of the University of Vienna and Medical University of Vienna
| | - Triin Laos
- Max Perutz Labs, University of Vienna, Vienna Biocenter (VBC), Dr Bohr-Gasse 9, A-1030 Vienna, Austria; Vienna BioCenter PhD Program, Doctoral School of the University of Vienna and Medical University of Vienna
| | - Elisabeth Holzer
- Max Perutz Labs, University of Vienna, Vienna Biocenter (VBC), Dr Bohr-Gasse 9, A-1030 Vienna, Austria
| | - Margarita Dillinger
- Max Perutz Labs, University of Vienna, Vienna Biocenter (VBC), Dr Bohr-Gasse 9, A-1030 Vienna, Austria
| | - Alexander Dammermann
- Max Perutz Labs, University of Vienna, Vienna Biocenter (VBC), Dr Bohr-Gasse 9, A-1030 Vienna, Austria.
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16
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O'Connell KF. Centrosomes: An acentriolar MTOC at the ciliary base. Curr Biol 2021; 31:R730-R733. [PMID: 34102124 DOI: 10.1016/j.cub.2021.03.101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Centrioles are microtubule-based organelles that are embedded within pericentriolar material (PCM). Together, they comprise the centrosome, a microtubule-organizing center. PCM can sometimes exist in the absence of centrioles, but a new example of acentriolar PCM in neurons offers deeper insight into the relationship between these two entities.
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Affiliation(s)
- Kevin F O'Connell
- Laboratory of Biochemistry and Genetics, National Institutes of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0380, USA.
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17
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Chen C, Xu Q, Zhang Y, Davies BA, Huang Y, Katzmann DJ, Harris PC, Hu J, Ling K. Ciliopathy protein HYLS1 coordinates the biogenesis and signaling of primary cilia by activating the ciliary lipid kinase PIPKIγ. SCIENCE ADVANCES 2021; 7:7/26/eabe3401. [PMID: 34162535 PMCID: PMC8221637 DOI: 10.1126/sciadv.abe3401] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 05/10/2021] [Indexed: 05/04/2023]
Abstract
Mutation of ciliopathy protein HYLS1 causes the perinatal lethal hydrolethalus syndrome (HLS), yet the underlying molecular etiology and pathogenesis remain elusive. Here, we reveal unexpected mechanistic insights into the role of mammalian HYLS1 in regulating primary cilia. HYLS1 is recruited to the ciliary base via a direct interaction with the type Iγ phosphatidylinositol 4-phosphate [PI(4)P] 5-kinase (PIPKIγ). HYLS1 activates PIPKIγ by interrupting the autoinhibitory dimerization of PIPKIγ, which thereby expedites depletion of centrosomal PI(4)P to allow axoneme nucleation. HYLS1 deficiency interrupts the assembly of ciliary NPHP module and agonist-induced ciliary exit of β-arrestin, which, in turn, disturbs the removal of ciliary Gpr161 and activation of hedgehog (Hh) signaling. Consistent with this model of pathogenesis, the HLS mutant HYLS1D211G supports ciliogenesis but not activation of Hh signaling. These results implicate mammalian HYLS1 as a multitasking protein that facilitates ciliogenesis and ciliary signaling by coordinating with the ciliary lipid kinase PIPKIγ.
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Affiliation(s)
- Chuan Chen
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN 55905, USA
| | - Qingwen Xu
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA
| | - Yuxia Zhang
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN 55905, USA
| | - Brian A Davies
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA
| | - Yan Huang
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN 55905, USA
| | - David J Katzmann
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA
| | - Peter C Harris
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN 55905, USA
| | - Jinghua Hu
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN 55905, USA
| | - Kun Ling
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA.
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18
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Magescas J, Eskinazi S, Tran MV, Feldman JL. Centriole-less pericentriolar material serves as a microtubule organizing center at the base of C. elegans sensory cilia. Curr Biol 2021; 31:2410-2417.e6. [PMID: 33798428 DOI: 10.1016/j.cub.2021.03.022] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 01/18/2021] [Accepted: 03/05/2021] [Indexed: 01/20/2023]
Abstract
During mitosis in animal cells, the centrosome acts as a microtubule organizing center (MTOC) to assemble the mitotic spindle. MTOC function at the centrosome is driven by proteins within the pericentriolar material (PCM), however the molecular complexity of the PCM makes it difficult to differentiate the proteins required for MTOC activity from other centrosomal functions. We used the natural spatial separation of PCM proteins during mitotic exit to identify a minimal module of proteins required for centrosomal MTOC function in C. elegans. Using tissue-specific degradation, we show that SPD-5, the functional homolog of CDK5RAP2, is essential for embryonic mitosis, while SPD-2/CEP192 and PCMD-1, which are essential in the one-cell embryo, are dispensable. Surprisingly, although the centriole is known to be degraded in the ciliated sensory neurons in C. elegans,1-3 we find evidence for "centriole-less PCM" at the base of cilia and use this structure as a minimal testbed to dissect centrosomal MTOC function. Super-resolution imaging revealed that this PCM inserts inside the lumen of the ciliary axoneme and directly nucleates the assembly of dendritic microtubules toward the cell body. Tissue-specific degradation in ciliated sensory neurons revealed a role for SPD-5 and the conserved microtubule nucleator γ-TuRC, but not SPD-2 or PCMD-1, in MTOC function at centriole-less PCM. This MTOC function was in the absence of regulation by mitotic kinases, highlighting the intrinsic ability of these proteins to drive microtubule growth and organization and further supporting a model that SPD-5 is the primary driver of MTOC function at the PCM.
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Affiliation(s)
- Jérémy Magescas
- Department of Biology, Stanford University, 371 Serra Mall, Stanford, 94305, CA, USA.
| | - Sani Eskinazi
- Department of Biology, Stanford University, 371 Serra Mall, Stanford, 94305, CA, USA
| | - Michael V Tran
- Department of Biology, Stanford University, 371 Serra Mall, Stanford, 94305, CA, USA
| | - Jessica L Feldman
- Department of Biology, Stanford University, 371 Serra Mall, Stanford, 94305, CA, USA.
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19
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Akella JS, Barr MM. The tubulin code specializes neuronal cilia for extracellular vesicle release. Dev Neurobiol 2021; 81:231-252. [PMID: 33068333 PMCID: PMC8052387 DOI: 10.1002/dneu.22787] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 09/07/2020] [Accepted: 09/23/2020] [Indexed: 12/17/2022]
Abstract
Cilia are microtubule-based organelles that display diversity in morphology, ultrastructure, protein composition, and function. The ciliary microtubules of C. elegans sensory neurons exemplify this diversity and provide a paradigm to understand mechanisms driving ciliary specialization. Only a subset of ciliated neurons in C. elegans are specialized to make and release bioactive extracellular vesicles (EVs) into the environment. The cilia of extracellular vesicle releasing neurons have distinct axonemal features and specialized intraflagellar transport that are important for releasing EVs. In this review, we discuss the role of the tubulin code in the specialization of microtubules in cilia of EV releasing neurons.
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Affiliation(s)
- Jyothi S Akella
- Department of Genetics and Human Genetics Institute of New Jersey, Rutgers University, Piscataway, NJ, USA
| | - Maureen M Barr
- Department of Genetics and Human Genetics Institute of New Jersey, Rutgers University, Piscataway, NJ, USA
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20
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Role of DZIP1-CBY-FAM92 transition zone complex in the basal body to membrane attachment and ciliary budding. Biochem Soc Trans 2021; 48:1067-1075. [PMID: 32491167 DOI: 10.1042/bst20191007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 04/20/2020] [Accepted: 05/07/2020] [Indexed: 02/07/2023]
Abstract
Cilia play important signaling or motile functions in various organisms. In Human, cilia dysfunctions are responsible for a wide range of diseases, called ciliopathies. Cilia assembly is a tightly controlled process, which starts with the conversion of the centriole into a basal body, leading to the formation of the ciliary bud that protrudes inside a ciliary vesicle and/or ultimately at the cell surface. Ciliary bud formation is associated with the assembly of the transition zone (TZ), a complex architecture of proteins of the ciliary base which plays critical functions in gating proteins in and out of the ciliary compartment. Many proteins are involved in the assembly of the TZ, which shows structural and functional variations in different cell types or organisms. In this review, we discuss how a particular complex, composed of members of the DZIP1, CBY and FAM92 families of proteins, is required for the initial stages of cilia assembly leading to ciliary bud formation and how their functional hierarchy contributes to TZ assembly. Moreover, we summarize how evidences in Drosophila reveal functional differences of the DZIP1-CBY-FAM92 complex in the different ciliated tissues of this organism. Whereas it is essential for proper TZ assembly in the two types of ciliated tissues, it is involved in stable anchoring of basal bodies to the plasma membrane in male germ cells. Overall, the DZIP1-CBY-FAM92 complex reveals a molecular assembly pathway required for the initial stages of ciliary bud formation and that is conserved from Drosophila to Human.
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21
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Nechipurenko I, Lavrentyeva S, Sengupta P. GRDN-1/Girdin regulates dendrite morphogenesis and cilium position in two specialized sensory neuron types in C. elegans. Dev Biol 2021; 472:38-51. [PMID: 33460640 DOI: 10.1016/j.ydbio.2020.12.022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 12/18/2020] [Accepted: 12/22/2020] [Indexed: 10/22/2022]
Abstract
Primary cilia are located at the dendritic tips of sensory neurons and house the molecular machinery necessary for detection and transduction of sensory stimuli. The mechanisms that coordinate dendrite extension with cilium position during sensory neuron development are not well understood. Here, we show that GRDN-1, the Caenorhabditis elegans ortholog of the highly conserved scaffold and signaling protein Girdin/GIV, regulates both cilium position and dendrite extension in the postembryonic AQR and PQR gas-sensing neurons. Mutations in grdn-1 disrupt dendrite outgrowth and mislocalize cilia to the soma or proximal axonal segments in AQR, and to a lesser extent, in PQR. GRDN-1 is localized to the basal body and regulates localization of HMR-1/Cadherin to the distal AQR dendrite. However, knockdown of HMR-1 and/or loss of SAX-7/LICAM, molecules previously implicated in sensory dendrite development in C. elegans, do not alter AQR dendrite morphology or cilium position. We find that GRDN-1 localization in AQR is regulated by UNC-116/Kinesin-1, and that correspondingly, unc-116 mutants exhibit severe AQR dendrite outgrowth and cilium positioning defects. In contrast, GRDN-1 and cilium localization in PQR is modulated by LIN-44/Wnt signaling. Together, these findings identify upstream regulators of GRDN-1, and describe new cell-specific roles for this multifunctional protein in sensory neuron development.
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Affiliation(s)
- Inna Nechipurenko
- Department of Biology, Brandeis University, Waltham, MA, USA; Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, MA, USA.
| | | | - Piali Sengupta
- Department of Biology, Brandeis University, Waltham, MA, USA.
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22
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Abstract
Cryo-electron tomography (cryo-ET) is an extremely powerful tool which is used to image cellular features in their close-to-native environment at a resolution where both protein structure and membrane morphology can be revealed. Compared to conventional electron microscopy methods for biology, cryo-ET does not include the use of potentially artifact generating agents for sample fixation or visualization. Despite its obvious advantages, cryo-ET has not been widely adopted by cell biologists. This might originate from the overwhelming and constantly growing number of complex ways to record and process data as well as the numerous methods available for sample preparation. In this chapter, we will take one step back and guide the reader through the essential steps of sample preparation using mammalian cells, as well as the basic steps involved in data recording and processing. The described protocol will allow the reader to obtain data that can be used for morphological analysis and precise measurements of biological structures in their cellular environment. Furthermore, this data can be used for more elaborate structural analysis by applying further image processing steps like subtomogram averaging, which is required to determine the structure of proteins.
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23
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Establishing and regulating the composition of cilia for signal transduction. Nat Rev Mol Cell Biol 2020; 20:389-405. [PMID: 30948801 DOI: 10.1038/s41580-019-0116-4] [Citation(s) in RCA: 246] [Impact Index Per Article: 61.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The primary cilium is a hair-like surface-exposed organelle of the eukaryotic cell that decodes a variety of signals - such as odorants, light and Hedgehog morphogens - by altering the local concentrations and activities of signalling proteins. Signalling within the cilium is conveyed through a diverse array of second messengers, including conventional signalling molecules (such as cAMP) and some unusual intermediates (such as sterols). Diffusion barriers at the ciliary base establish the unique composition of this signalling compartment, and cilia adapt their proteome to signalling demands through regulated protein trafficking. Much progress has been made on the molecular understanding of regulated ciliary trafficking, which encompasses not only exchanges between the cilium and the rest of the cell but also the shedding of signalling factors into extracellular vesicles.
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24
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Akella JS, Carter SP, Nguyen K, Tsiropoulou S, Moran AL, Silva M, Rizvi F, Kennedy BN, Hall DH, Barr MM, Blacque OE. Ciliary Rab28 and the BBSome negatively regulate extracellular vesicle shedding. eLife 2020; 9:e50580. [PMID: 32101165 PMCID: PMC7043889 DOI: 10.7554/elife.50580] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Accepted: 02/02/2020] [Indexed: 12/15/2022] Open
Abstract
Cilia both receive and send information, the latter in the form of extracellular vesicles (EVs). EVs are nano-communication devices that influence cell, tissue, and organism behavior. Mechanisms driving ciliary EV biogenesis are almost entirely unknown. Here, we show that the ciliary G-protein Rab28, associated with human autosomal recessive cone-rod dystrophy, negatively regulates EV levels in the sensory organs of Caenorhabditis elegans in a cilia specific manner. Sequential targeting of lipidated Rab28 to periciliary and ciliary membranes is highly dependent on the BBSome and the prenyl-binding protein phosphodiesterase 6 subunit delta (PDE6D), respectively, and BBSome loss causes excessive and ectopic EV production. We also find that EV defective mutants display abnormalities in sensory compartment morphogenesis. Together, these findings reveal that Rab28 and the BBSome are key in vivo regulators of EV production at the periciliary membrane and suggest that EVs may mediate signaling between cilia and glia to shape sensory organ compartments. Our data also suggest that defects in the biogenesis of cilia-related EVs may contribute to human ciliopathies.
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Affiliation(s)
- Jyothi S Akella
- Department of Genetics and Human Genetics Institute of New Jersey, Rutgers UniversityPiscatawayUnited States
| | - Stephen P Carter
- School of Biomolecular and Biomedical Science, Conway Institute, University College DublinDublinIreland
| | - Ken Nguyen
- Center for C. elegans Anatomy, Albert Einstein College of MedicineBronxUnited States
| | - Sofia Tsiropoulou
- School of Biomolecular and Biomedical Science, Conway Institute, University College DublinDublinIreland
| | - Ailis L Moran
- School of Biomolecular and Biomedical Science, Conway Institute, University College DublinDublinIreland
| | - Malan Silva
- Department of Genetics and Human Genetics Institute of New Jersey, Rutgers UniversityPiscatawayUnited States
- Department of Biology, University of UtahSalt Lake CityUnited States
| | - Fatima Rizvi
- Department of Genetics and Human Genetics Institute of New Jersey, Rutgers UniversityPiscatawayUnited States
| | - Breandan N Kennedy
- School of Biomolecular and Biomedical Science, Conway Institute, University College DublinDublinIreland
| | - David H Hall
- Center for C. elegans Anatomy, Albert Einstein College of MedicineBronxUnited States
| | - Maureen M Barr
- Department of Genetics and Human Genetics Institute of New Jersey, Rutgers UniversityPiscatawayUnited States
| | - Oliver E Blacque
- School of Biomolecular and Biomedical Science, Conway Institute, University College DublinDublinIreland
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25
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Differential Requirements for Centrioles in Mitotic Centrosome Growth and Maintenance. Dev Cell 2019; 50:355-366.e6. [DOI: 10.1016/j.devcel.2019.06.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Revised: 03/29/2019] [Accepted: 06/10/2019] [Indexed: 10/26/2022]
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26
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Joukov V, De Nicolo A. The Centrosome and the Primary Cilium: The Yin and Yang of a Hybrid Organelle. Cells 2019; 8:E701. [PMID: 31295970 PMCID: PMC6678760 DOI: 10.3390/cells8070701] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 07/04/2019] [Accepted: 07/06/2019] [Indexed: 12/27/2022] Open
Abstract
Centrosomes and primary cilia are usually considered as distinct organelles, although both are assembled with the same evolutionary conserved, microtubule-based templates, the centrioles. Centrosomes serve as major microtubule- and actin cytoskeleton-organizing centers and are involved in a variety of intracellular processes, whereas primary cilia receive and transduce environmental signals to elicit cellular and organismal responses. Understanding the functional relationship between centrosomes and primary cilia is important because defects in both structures have been implicated in various diseases, including cancer. Here, we discuss evidence that the animal centrosome evolved, with the transition to complex multicellularity, as a hybrid organelle comprised of the two distinct, but intertwined, structural-functional modules: the centriole/primary cilium module and the pericentriolar material/centrosome module. The evolution of the former module may have been caused by the expanding cellular diversification and intercommunication, whereas that of the latter module may have been driven by the increasing complexity of mitosis and the requirement for maintaining cell polarity, individuation, and adhesion. Through its unique ability to serve both as a plasma membrane-associated primary cilium organizer and a juxtanuclear microtubule-organizing center, the animal centrosome has become an ideal integrator of extracellular and intracellular signals with the cytoskeleton and a switch between the non-cell autonomous and the cell-autonomous signaling modes. In light of this hypothesis, we discuss centrosome dynamics during cell proliferation, migration, and differentiation and propose a model of centrosome-driven microtubule assembly in mitotic and interphase cells. In addition, we outline the evolutionary benefits of the animal centrosome and highlight the hierarchy and modularity of the centrosome biogenesis networks.
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Affiliation(s)
- Vladimir Joukov
- N.N. Petrov National Medical Research Center of Oncology, 197758 Saint-Petersburg, Russia.
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27
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DiTirro D, Philbrook A, Rubino K, Sengupta P. The Caenorhabditis elegans Tubby homolog dynamically modulates olfactory cilia membrane morphogenesis and phospholipid composition. eLife 2019; 8:48789. [PMID: 31259686 PMCID: PMC6624019 DOI: 10.7554/elife.48789] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 06/21/2019] [Indexed: 12/13/2022] Open
Abstract
Plasticity in sensory signaling is partly mediated via regulated trafficking of signaling molecules to and from primary cilia. Tubby-related proteins regulate ciliary protein transport; however, their roles in remodeling cilia properties are not fully understood. We find that the C. elegans TUB-1 Tubby homolog regulates membrane morphogenesis and signaling protein transport in specialized sensory cilia. In particular, TUB-1 is essential for sensory signaling-dependent reshaping of olfactory cilia morphology. We show that compromised sensory signaling alters cilia membrane phosphoinositide composition via TUB-1-dependent trafficking of a PIP5 kinase. TUB-1 regulates localization of this lipid kinase at the cilia base in part via localization of the AP-2 adaptor complex subunit DPY-23. Our results describe new functions for Tubby proteins in the dynamic regulation of cilia membrane lipid composition, morphology, and signaling protein content, and suggest that this conserved family of proteins plays a critical role in mediating cilia structural and functional plasticity.
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Affiliation(s)
- Danielle DiTirro
- Department of Biology, Brandeis University, Waltham, United States
| | - Alison Philbrook
- Department of Biology, Brandeis University, Waltham, United States
| | - Kendrick Rubino
- Department of Biology, Brandeis University, Waltham, United States
| | - Piali Sengupta
- Department of Biology, Brandeis University, Waltham, United States
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28
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Akella JS, Silva M, Morsci NS, Nguyen KC, Rice WJ, Hall DH, Barr MM. Cell type-specific structural plasticity of the ciliary transition zone in C. elegans. Biol Cell 2019; 111:95-107. [PMID: 30681171 DOI: 10.1111/boc.201800042] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Revised: 11/15/2018] [Accepted: 11/18/2018] [Indexed: 12/13/2022]
Abstract
BACKGROUND INFORMATION The current consensus on cilia development posits that the ciliary transition zone (TZ) is formed via extension of nine centrosomal microtubules. In this model, TZ structure remains unchanged in microtubule number throughout the cilium life cycle. This model does not however explain structural variations of TZ structure seen in nature and could also lend itself to the misinterpretation that deviations from nine-doublet microtubule ultrastructure represent an abnormal phenotype. Thus, a better understanding of events that occur at the TZ in vivo during metazoan development is required. RESULTS To address this issue, we characterized ultrastructure of two types of sensory cilia in developing Caenorhabditis elegans. We discovered that, in cephalic male (CEM) and inner labial quadrant (IL2Q) sensory neurons, ciliary TZs are structurally plastic and remodel from one structure to another during animal development. The number of microtubule doublets forming the TZ can be increased or decreased over time, depending on cilia type. Both cases result in structural TZ intermediates different from TZ in cilia of adult animals. In CEM cilia, axonemal extension and maturation occurs concurrently with TZ structural maturation. CONCLUSIONS AND SIGNIFICANCE Our work extends the current model to include the structural plasticity of metazoan transition zone, which can be structurally delayed, maintained or remodelled in cell type-specific manner.
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Affiliation(s)
- Jyothi S Akella
- Department of Genetics and Human Genetics Institute of New Jersey, Rutgers University, Piscataway, NJ, 08854, USA
| | - Malan Silva
- Department of Genetics and Human Genetics Institute of New Jersey, Rutgers University, Piscataway, NJ, 08854, USA.,Department of Biology, University of Utah, Salt Lake City, UT, 84112, USA
| | | | - Ken C Nguyen
- Center for C. elegans Anatomy, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - William J Rice
- Simons Electron Microscopy Center, New York Structural Biology Center, NY, 10027, USA
| | - David H Hall
- Center for C. elegans Anatomy, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Maureen M Barr
- Department of Genetics and Human Genetics Institute of New Jersey, Rutgers University, Piscataway, NJ, 08854, USA
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29
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Harterink M, Edwards SL, de Haan B, Yau KW, van den Heuvel S, Kapitein LC, Miller KG, Hoogenraad CC. Local microtubule organization promotes cargo transport in C. elegans dendrites. J Cell Sci 2018; 131:jcs.223107. [PMID: 30254025 DOI: 10.1242/jcs.223107] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 09/14/2018] [Indexed: 02/05/2023] Open
Abstract
The specific organization of the neuronal microtubule cytoskeleton in axons and dendrites is an evolutionarily conserved determinant of neuronal polarity that allows for selective cargo sorting. However, how dendritic microtubules are organized and whether local differences influence cargo transport remains largely unknown. Here, we use live-cell imaging to systematically probe the microtubule organization in Caenorhabditis elegans neurons, and demonstrate the contribution of distinct mechanisms in the organization of dendritic microtubules. We found that most non-ciliated neurons depend on unc-116 (kinesin-1), unc-33 (CRMP) and unc-44 (ankyrin) for correct microtubule organization and polarized cargo transport, as previously reported. Ciliated neurons and the URX neuron, however, use an additional pathway to nucleate microtubules at the tip of the dendrite, from the base of the cilium in ciliated neurons. Since inhibition of distal microtubule nucleation affects distal dendritic transport, we propose a model in which the presence of a microtubule-organizing center at the dendrite tip ensures correct dendritic cargo transport.
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Affiliation(s)
- Martin Harterink
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, 3584 Utrecht, The Netherlands
| | - Stacey L Edwards
- Genetic Models of Disease Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, US
| | - Bart de Haan
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, 3584 Utrecht, The Netherlands
| | - Kah Wai Yau
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, 3584 Utrecht, The Netherlands
| | - Sander van den Heuvel
- Developmental Biology, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, 3584 Utrecht, The Netherlands
| | - Lukas C Kapitein
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, 3584 Utrecht, The Netherlands
| | - Kenneth G Miller
- Genetic Models of Disease Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, US
| | - Casper C Hoogenraad
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, 3584 Utrecht, The Netherlands
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30
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Gupta A, Fabian L, Brill JA. Phosphatidylinositol 4,5-bisphosphate regulates cilium transition zone maturation in Drosophila melanogaster. J Cell Sci 2018; 131:jcs.218297. [PMID: 30054387 DOI: 10.1242/jcs.218297] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 07/11/2018] [Indexed: 01/06/2023] Open
Abstract
Cilia are cellular antennae that are essential for human development and physiology. A large number of genetic disorders linked to cilium dysfunction are associated with proteins that localize to the ciliary transition zone (TZ), a structure at the base of cilia that regulates trafficking in and out of the cilium. Despite substantial effort to identify TZ proteins and their roles in cilium assembly and function, processes underlying maturation of TZs are not well understood. Here, we report a role for the membrane lipid phosphatidylinositol 4,5-bisphosphate (PIP2) in TZ maturation in the Drosophila melanogaster male germline. We show that reduction of cellular PIP2 levels through ectopic expression of a phosphoinositide phosphatase or mutation of the type I phosphatidylinositol phosphate kinase Skittles induces formation of longer than normal TZs. These hyperelongated TZs exhibit functional defects, including loss of plasma membrane tethering. We also report that the onion rings (onr) allele of DrosophilaExo84 decouples TZ hyperelongation from loss of cilium-plasma membrane tethering. Our results reveal a requirement for PIP2 in supporting ciliogenesis by promoting proper TZ maturation.
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Affiliation(s)
- Alind Gupta
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, M5S 1A8, Canada.,Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario, M5G 0A4, Canada
| | - Lacramioara Fabian
- Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario, M5G 0A4, Canada
| | - Julie A Brill
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, M5S 1A8, Canada .,Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario, M5G 0A4, Canada.,Institute of Medical Science, University of Toronto, Toronto, Ontario, M5S 1A8, Canada
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31
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Uzbekov R, Garanina A, Bressac C. Centrioles without microtubules: a new morphological type of centriole. Biol Open 2018; 7:bio036012. [PMID: 29997243 PMCID: PMC6124565 DOI: 10.1242/bio.036012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Accepted: 07/03/2018] [Indexed: 12/21/2022] Open
Abstract
The centrosome is the organizing center of microtubules in the cell, the basis for the origin of cilia and flagella and a site for the concentration of a regulatory proteins multitude. The centrosome comprises two centrioles surrounded by pericentriolar material. Centrioles in the cells of different organisms can contain nine triplets, doublets or singlets of microtubules. Here, we show that in somatic cells of male wasp larvae Anisopteromalus calandrae, centrioles do not contain microtubules and are composed of nine electron-dense prongs, which together form a cogwheel structure. These microtubule-free centrioles can be the platform for procentriole formation and form microtubule-free cilia-like structures. In nymph and imago cells centrioles have a microtubule triplet structure. Our study describes how centriole structure differs in a development-stage-dependent and a cell-type-dependent manner. The discovery of a centriole without microtubules casts a new light on the centriole formation process and the evolution of this organelle.
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Affiliation(s)
- Rustem Uzbekov
- Department of Microscopy, University of Tours, Tours 37032, France
- Faculty of Bioengineering and Bioinformatics, Moscow State University, Moscow 119992, Russia
| | | | - Christophe Bressac
- Institute of Research on Insect Biology, IMIP research team UMR CNRS 7261, University of AQ1 Tours, Tours 37200, France
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32
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Revisiting Centrioles in Nematodes-Historic Findings and Current Topics. Cells 2018; 7:cells7080101. [PMID: 30096824 PMCID: PMC6115991 DOI: 10.3390/cells7080101] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 07/23/2018] [Accepted: 07/24/2018] [Indexed: 01/02/2023] Open
Abstract
Theodor Boveri is considered as the “father” of centrosome biology. Boveri’s fundamental findings have laid the groundwork for decades of research on centrosomes. Here, we briefly review his early work on centrosomes and his first description of the centriole. Mainly focusing on centriole structure, duplication, and centriole assembly factors in C. elegans, we will highlight the role of this model in studying germ line centrosomes in nematodes. Last but not least, we will point to future directions of the C. elegans centrosome field.
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33
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Gupta A, Kitagawa D. Ultrastructural diversity between centrioles of eukaryotes. J Biochem 2018; 164:1-8. [PMID: 29462371 DOI: 10.1093/jb/mvy031] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 02/07/2018] [Indexed: 01/05/2023] Open
Abstract
Several decades of centriole research have revealed the beautiful symmetry present in these microtubule-based organelles, which are required to form centrosomes, cilia and flagella in many eukaryotes. Centriole architecture is largely conserved across most organisms; however, individual centriolar features such as the central cartwheel or microtubule walls exhibit considerable variability when examined with finer resolution. In this paper, we review the ultrastructural characteristics of centrioles in commonly studied organisms, highlighting the subtle and not-so-subtle differences between specific structural components of these centrioles. In addition, we survey some non-canonical centriole structures that have been discovered in various species, from the coaxial bicentrioles of protists and lower land plants to the giant irregular centrioles of the fungus gnat Sciara. Finally, we speculate on the functional significance of these differences between centrioles, and the contribution of individual structural elements such as the cartwheel or microtubules towards the stability of centrioles.
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Affiliation(s)
- Akshari Gupta
- Division of Centrosome Biology, Department of Molecular Genetics, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan.,Department of Genetics, School of Life Science, Graduate University for Advanced Studies (SOKENDAI), Mishima, Shizuoka 411-8540, Japan.,Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology (EPFL), CH-1015 Lausanne, Switzerland
| | - Daiju Kitagawa
- Division of Centrosome Biology, Department of Molecular Genetics, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan.,Department of Genetics, School of Life Science, Graduate University for Advanced Studies (SOKENDAI), Mishima, Shizuoka 411-8540, Japan
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34
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Garcia G, Raleigh DR, Reiter JF. How the Ciliary Membrane Is Organized Inside-Out to Communicate Outside-In. Curr Biol 2018; 28:R421-R434. [PMID: 29689227 PMCID: PMC6434934 DOI: 10.1016/j.cub.2018.03.010] [Citation(s) in RCA: 105] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Cilia, organelles that move to execute functions like fertilization and signal to execute functions like photoreception and embryonic patterning, are composed of a core of nine-fold doublet microtubules overlain by a membrane. Distinct types of cilia display distinct membrane morphologies, ranging from simple domed cylinders to the highly ornate invaginations and membrane disks of photoreceptor outer segments. Critical for the ability of cilia to signal, both the protein and the lipid compositions of ciliary membranes are different from those of other cellular membranes. This specialization presents a unique challenge for the cell as, unlike membrane-bounded organelles, the ciliary membrane is contiguous with the surrounding plasma membrane. This distinct ciliary membrane is generated in concert with multiple membrane remodeling events that comprise the process of ciliogenesis. Once the cilium is formed, control of ciliary membrane composition relies on discrete molecular machines, including a barrier to membrane proteins entering the cilium at a specialized region of the base of the cilium called the transition zone and a trafficking adaptor that controls G protein-coupled receptor (GPCR) localization to the cilium called the BBSome. The ciliary membrane can be further remodeled by the removal of membrane proteins by the release of ciliary extracellular vesicles that may function in intercellular communication, removal of unneeded proteins or ciliary disassembly. Here, we review the structures and transport mechanisms that control ciliary membrane composition, and discuss how membrane specialization enables the cilium to function as the antenna of the cell.
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Affiliation(s)
- Galo Garcia
- Department of Biochemistry and Biophysics, Cardiovascular Research Institute, University of California, San Francisco, CA 94158, USA
| | - David R Raleigh
- Department of Biochemistry and Biophysics, Cardiovascular Research Institute, University of California, San Francisco, CA 94158, USA; Department of Radiation Oncology, University of California, San Francisco, CA 94143, USA; Department of Neurological Surgery, University of California, San Francisco, CA 94143, USA
| | - Jeremy F Reiter
- Department of Biochemistry and Biophysics, Cardiovascular Research Institute, University of California, San Francisco, CA 94158, USA.
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35
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Wang JT, Stearns T. The ABCs of Centriole Architecture: The Form and Function of Triplet Microtubules. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 2018; 82:145-155. [PMID: 29540555 PMCID: PMC11156431 DOI: 10.1101/sqb.2017.82.034496] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/09/2024]
Abstract
The centriole is a defining feature of many eukaryotic cells. It nucleates a cilium, organizes microtubules as part of the centrosome, and is duplicated in coordination with the cell cycle. Centrioles have a remarkable structure, consisting of microtubules arranged in a barrel with ninefold radial symmetry. At their base, or proximal end, centrioles have unique triplet microtubules, formed from three microtubules linked to each other. This microtubule organization is not found anywhere else in the cell, is conserved in all major branches of the eukaryotic tree, and likely was present in the last eukaryotic common ancestor. At their tip, or distal end, centrioles have doublet microtubules, which template the cilium. Here, we consider the structures of the compound microtubules in centrioles and discuss potential mechanisms for their formation and their function. We propose that triplet microtubules are required for the structural integrity of centrioles, allowing the centriole to serve as the essential nucleator of the cilium.
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Affiliation(s)
- Jennifer T Wang
- Department of Biology, Stanford University, Stanford, California 94305-5020
| | - Tim Stearns
- Department of Biology, Stanford University, Stanford, California 94305-5020
- Department of Genetics, Stanford School of Medicine, Stanford, California 94305
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36
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Riparbelli MG, Persico V, Gottardo M, Callaini G. The developing Drosophila eye - a new model to study centriole reduction. J Cell Sci 2018; 131:jcs.211441. [PMID: 29361550 DOI: 10.1242/jcs.211441] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Accepted: 01/15/2018] [Indexed: 01/06/2023] Open
Abstract
In the developing Drosophila eye, the centrioles of the differentiating retinal cells are not surrounded by the microtubule-nucleating γ-tubulin, suggesting that they are unable to organize functional microtubule-organizing centers. Consistent with this idea, Cnn and Spd-2, which are involved in γ-tubulin recruitment, and the scaffold protein Plp, which plays a role in the organization of the pericentriolar material, are lost in the third-instar larval stage. However, the centrioles maintain their structural integrity, and both the parent centrioles accumulate Asl and Ana1. Although the loading of Asl points to the acquisition of the motherhood condition, the daughter centrioles fail to recruit Plk4 and do not duplicate. However, it is surprising that the mother centrioles that accumulate Plk4 also never duplicate. This suggests that the loading of Plk4 is not sufficient, in this system, to allow centriole duplication. By halfway through pupal life, the centriole number decreases and structural defects, ranging from being incomplete or lacking B-tubules, are detected. Asl, Ana1 and Sas-4 are still present, suggesting that the centriole integrity does not depend on these proteins.
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Affiliation(s)
- Maria G Riparbelli
- Department of Life Sciences, Via A. Moro 2, University of Siena, 53100 Siena, Italy
| | - Veronica Persico
- Department of Life Sciences, Via A. Moro 2, University of Siena, 53100 Siena, Italy
| | - Marco Gottardo
- Department of Life Sciences, Via A. Moro 2, University of Siena, 53100 Siena, Italy
| | - Giuliano Callaini
- Department of Life Sciences, Via A. Moro 2, University of Siena, 53100 Siena, Italy
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37
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New Roles of the Primary Cilium in Autophagy. BIOMED RESEARCH INTERNATIONAL 2017; 2017:4367019. [PMID: 28913352 PMCID: PMC5587941 DOI: 10.1155/2017/4367019] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 07/03/2017] [Indexed: 12/21/2022]
Abstract
The primary cilium is a nonmotile organelle that emanates from the surface of multiple cell types and receives signals from the environment to regulate intracellular signaling pathways. The presence of cilia, as well as their length, is important for proper cell function; shortened, elongated, or absent cilia are associated with pathological conditions. Interestingly, it has recently been shown that the molecular machinery involved in autophagy, the process of recycling of intracellular material to maintain cellular and tissue homeostasis, participates in ciliogenesis. Cilium-dependent signaling is necessary for autophagosome formation and, conversely, autophagy regulates both ciliogenesis and cilium length by degrading specific ciliary proteins. Here, we will discuss the relationship that exists between the two processes at the cellular and molecular level, highlighting what is known about the effects of ciliary dysfunction in the control of energy homeostasis in some ciliopathies.
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38
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Nechipurenko IV, Sengupta P. The rise and fall of basal bodies in the nematode Caenorhabditis elegans. Cilia 2017; 6:9. [PMID: 28770089 PMCID: PMC5530580 DOI: 10.1186/s13630-017-0053-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Accepted: 07/11/2017] [Indexed: 11/17/2022] Open
Abstract
The free-living nematode, Caenorhabditis elegans, is a widely used genetic model organism for investigations into centriole and cilia biology. Only sensory neurons are ciliated in C. elegans; morphologically diverse cilia in these neurons are nucleated by basal bodies located at the dendritic endings. C. elegans centrioles comprise a central tube with a symmetric array of nine singlet microtubules. These singlet microtubules remodel in a subset of sensory neurons to form the doublet microtubules of the basal bodies. Following initiation of ciliogenesis, the central tube, but not the outer centriole wall, of the basal body degenerates. Recent ultrastructural characterization of basal body architecture and remodeling have laid the foundation for future studies into mechanisms underlying different aspects of basal body genesis, remodeling, and intracellular positioning.
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Affiliation(s)
- Inna V Nechipurenko
- Department of Biology and National Center for Behavioral Genomics, Brandeis University, Waltham, MA 02454 USA
| | - Piali Sengupta
- Department of Biology and National Center for Behavioral Genomics, Brandeis University, Waltham, MA 02454 USA
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39
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Li W, Yi P, Zhu Z, Zhang X, Li W, Ou G. Centriole translocation and degeneration during ciliogenesis in Caenorhabditis elegans neurons. EMBO J 2017; 36:2553-2566. [PMID: 28743734 DOI: 10.15252/embj.201796883] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Revised: 06/06/2017] [Accepted: 07/03/2017] [Indexed: 11/09/2022] Open
Abstract
Neuronal cilia that are formed at the dendritic endings of sensory neurons are essential for sensory perception. However, it remains unclear how the centriole-derived basal body is positioned to form a template for cilium formation. Using fluorescence time-lapse microscopy, we show that the centriole translocates from the cell body to the dendrite tip in the Caenorhabditis elegans sensory neurons. The centriolar protein SAS-5 interacts with the dynein light-chain LC8 and conditional mutations of cytoplasmic dynein-1 block centriole translocation and ciliogenesis. The components of the central tube are essential for the biogenesis of centrioles, which later drive ciliogenesis in the dendrite; however, the centriole loses these components at the late stage of centriole translocation and subsequently recruits transition zone and intraflagellar transport proteins. Together, our results provide a comprehensive model of ciliogenesis in sensory neurons and reveal the importance of the dynein-dependent centriole translocation in this process.
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Affiliation(s)
- Wenjing Li
- Tsinghua-Peking Center for Life Sciences, School of Life Sciences and MOE Key Laboratory for Protein Science, Tsinghua University, Beijing, China
| | - Peishan Yi
- Tsinghua-Peking Center for Life Sciences, School of Life Sciences and MOE Key Laboratory for Protein Science, Tsinghua University, Beijing, China
| | - Zhiwen Zhu
- Tsinghua-Peking Center for Life Sciences, School of Life Sciences and MOE Key Laboratory for Protein Science, Tsinghua University, Beijing, China
| | - Xianliang Zhang
- Tsinghua-Peking Center for Life Sciences, School of Life Sciences and MOE Key Laboratory for Protein Science, Tsinghua University, Beijing, China
| | - Wei Li
- Tsinghua-Peking Center for Life Sciences, School of Life Sciences and MOE Key Laboratory for Protein Science, Tsinghua University, Beijing, China
| | - Guangshuo Ou
- Tsinghua-Peking Center for Life Sciences, School of Life Sciences and MOE Key Laboratory for Protein Science, Tsinghua University, Beijing, China
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