1
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Jaiswal S, Sanghi S, Singh P. Separation-of-function MCPH-associated mutations in CPAP affect centriole number and length. J Cell Sci 2023; 136:jcs261297. [PMID: 37823337 DOI: 10.1242/jcs.261297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Accepted: 09/27/2023] [Indexed: 10/13/2023] Open
Abstract
Centrioles are microtubule-based cylindrical ultrastructures characterized by their definite size and robustness. The molecular capping protein, CPAP (also known as CENPJ) engages its N-terminal region with the centriole microtubules to regulate their length. Nevertheless, the conserved C-terminal glycine-rich G-box of CPAP, which interacts with the centriole inner cartwheel protein STIL, is frequently mutated in primary microcephaly (MCPH) patients. Here, we show that two different MCPH-associated variants, E1235V and D1196N in the CPAP G-box, affect distinct functions at centrioles. The E1235V mutation reduces CPAP centriole recruitment and causes overly long centrioles. The D1196N mutation increases centriole numbers without affecting centriole localization. Both mutations prevent binding to STIL, which controls centriole duplication. Our work highlights the involvement of an alternative CEP152-dependent route for CPAP centriole localization. Molecular dynamics simulations suggest that E1235V leads to an increase in G-box flexibility, which could have implications on its molecular interactions. Collectively, we demonstrate that a CPAP region outside the microtubule-interacting domains influences centriole number and length, which translates to spindle defects and reduced cell viability. Our work provides new insights into the molecular causes of primary microcephaly.
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Affiliation(s)
- Sonal Jaiswal
- Department of Bioscience & Bioengineering, Indian Institute of Technology Jodhpur, NH 62, Nagaur Road, Karwar 342037, Jodhpur, Rajasthan, India
| | - Srishti Sanghi
- Department of Bioscience & Bioengineering, Indian Institute of Technology Jodhpur, NH 62, Nagaur Road, Karwar 342037, Jodhpur, Rajasthan, India
| | - Priyanka Singh
- Department of Bioscience & Bioengineering, Indian Institute of Technology Jodhpur, NH 62, Nagaur Road, Karwar 342037, Jodhpur, Rajasthan, India
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2
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Huang F, Xu X, Xin G, Zhang B, Jiang Q, Zhang C. Cartwheel disassembly regulated by CDK1-cyclin B kinase allows human centriole disengagement and licensing. J Biol Chem 2022; 298:102658. [PMID: 36356903 PMCID: PMC9763691 DOI: 10.1016/j.jbc.2022.102658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Revised: 10/22/2022] [Accepted: 10/25/2022] [Indexed: 11/09/2022] Open
Abstract
Cartwheel assembly is considered the first step in the initiation of procentriole biogenesis; however, the reason for persistence of the assembled human cartwheel structure from S phase to late mitosis remains unclear. Here, we demonstrate mainly using cell synchronization, RNA interference, immunofluorescence and time-lapse-microscopy, biochemical analysis, and methods that the cartwheel persistently assembles and maintains centriole engagement and centrosome integrity during S phase to late G2 phase. Blockade of the continuous accumulation of centriolar Sas-6, a major cartwheel protein, after procentriole formation induces premature centriole disengagement and disrupts pericentriolar matrix integrity. Additionally, we determined that during mitosis, CDK1-cyclin B phosphorylates Sas-6 at T495 and S510, disrupting its binding to cartwheel component STIL and pericentriolar component Nedd1 and promoting cartwheel disassembly and centriole disengagement. Perturbation of this phosphorylation maintains the accumulation of centriolar Sas-6 and retains centriole engagement during mitotic exit, which results in the inhibition of centriole reduplication. Collectively, these data demonstrate that persistent cartwheel assembly after procentriole formation maintains centriole engagement and that this configuration is relieved through phosphorylation of Sas-6 by CDK1-cyclin B during mitosis in human cells.
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Affiliation(s)
- Fan Huang
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, College of Life Sciences, Peking University, Beijing, China
| | - Xiaowei Xu
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, College of Life Sciences, Peking University, Beijing, China
| | - Guangwei Xin
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, College of Life Sciences, Peking University, Beijing, China
| | - Boyan Zhang
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, College of Life Sciences, Peking University, Beijing, China
| | - Qing Jiang
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, College of Life Sciences, Peking University, Beijing, China
| | - Chuanmao Zhang
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, College of Life Sciences, Peking University, Beijing, China.
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3
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Soh AWJ, Pearson CG. Ciliate cortical organization and dynamics for cell motility: Comparing ciliates and vertebrates. J Eukaryot Microbiol 2022; 69:e12880. [PMID: 34897878 PMCID: PMC9188629 DOI: 10.1111/jeu.12880] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The generation of efficient fluid flow is crucial for organismal development and homeostasis, sexual reproduction, and motility. Multi-ciliated cells possess fields of motile cilia that beat in synchrony to propel fluid. Ciliary arrays are remarkably conserved in their organization and function. Ciliates have polarized multi-ciliary arrays (MCAs) to promote fluid flow for cell motility. The ciliate cortex is decorated with hundreds of basal bodies (BB) forming linear rows along the cell's anterior-posterior axis. BBs scaffold and position cilia to form the organized ciliary array. Nascent BBs assemble at the base of BBs. As nascent BBs mature, they integrate into the cortical BB and cytoskeletal network and nucleate their own cilium. The organization of MCAs is balanced between cortical stability and cortical dynamism. The cortical cytoskeletal network both establishes and maintains a stable organization of the MCA in the face of mechanical forces exerted by ciliary beating. At the same time, MCA organization is plastic, such that it remodels for optimal ciliary mobility during development and in response to environmental conditions. Such plasticity promotes effective feeding and ecological behavior required for these organisms. Together, these properties allow an organism to effectively sense, adapt to, and move through its environment.
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Affiliation(s)
- Adam W. J. Soh
- Anschutz Medical Campus, Department of Cell and Developmental Biology, University of Colorado, Aurora, CO 80045
| | - Chad G. Pearson
- Anschutz Medical Campus, Department of Cell and Developmental Biology, University of Colorado, Aurora, CO 80045
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4
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Bouhouche K, Valentine MS, Le Borgne P, Lemullois M, Yano J, Lodh S, Nabi A, Tassin AM, Van Houten JL. Paramecium, a Model to Study Ciliary Beating and Ciliogenesis: Insights From Cutting-Edge Approaches. Front Cell Dev Biol 2022; 10:847908. [PMID: 35359441 PMCID: PMC8964087 DOI: 10.3389/fcell.2022.847908] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Accepted: 02/14/2022] [Indexed: 12/30/2022] Open
Abstract
Cilia are ubiquitous and highly conserved extensions that endow the cell with motility and sensory functions. They were present in the first eukaryotes and conserved throughout evolution (Carvalho-Santos et al., 2011). Paramecium has around 4,000 motile cilia on its surface arranged in longitudinal rows, beating in waves to ensure movement and feeding. As with cilia in other model organisms, direction and speed of Paramecium ciliary beating is under bioelectric control of ciliary ion channels. In multiciliated cells of metazoans as well as paramecia, the cilia become physically entrained to beat in metachronal waves. This ciliated organism, Paramecium, is an attractive model for multidisciplinary approaches to dissect the location, structure and function of ciliary ion channels and other proteins involved in ciliary beating. Swimming behavior also can be a read-out of the role of cilia in sensory signal transduction. A cilium emanates from a BB, structurally equivalent to the centriole anchored at the cell surface, and elongates an axoneme composed of microtubule doublets enclosed in a ciliary membrane contiguous with the plasma membrane. The connection between the BB and the axoneme constitutes the transition zone, which serves as a diffusion barrier between the intracellular space and the cilium, defining the ciliary compartment. Human pathologies affecting cilia structure or function, are called ciliopathies, which are caused by gene mutations. For that reason, the molecular mechanisms and structural aspects of cilia assembly and function are actively studied using a variety of model systems, ranging from unicellular organisms to metazoa. In this review, we will highlight the use of Paramecium as a model to decipher ciliary beating mechanisms as well as high resolution insights into BB structure and anchoring. We will show that study of cilia in Paramecium promotes our understanding of cilia formation and function. In addition, we demonstrate that Paramecium could be a useful tool to validate candidate genes for ciliopathies.
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Affiliation(s)
- K. Bouhouche
- CEA, CNRS, Université Paris-Saclay, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | | | - P. Le Borgne
- CEA, CNRS, Université Paris-Saclay, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - M. Lemullois
- CEA, CNRS, Université Paris-Saclay, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - J. Yano
- Department of Biology, University of Vermont, Burlington, VT, United States
| | - S. Lodh
- Biological Sciences, Marquette University, Milwaukee, WI, United States
| | - A. Nabi
- Luminex, Austin, TX, United States
| | - A. M. Tassin
- CEA, CNRS, Université Paris-Saclay, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
- *Correspondence: A. M. Tassin, ; J. L. Van Houten,
| | - J. L. Van Houten
- Department of Biology, University of Vermont, Burlington, VT, United States
- *Correspondence: A. M. Tassin, ; J. L. Van Houten,
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5
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Kantsadi AL, Hatzopoulos GN, Gönczy P, Vakonakis I. Structures of SAS-6 coiled coil hold implications for the polarity of the centriolar cartwheel. Structure 2022; 30:671-684.e5. [PMID: 35240058 DOI: 10.1016/j.str.2022.02.005] [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: 03/18/2021] [Revised: 12/13/2021] [Accepted: 02/04/2022] [Indexed: 12/22/2022]
Abstract
Centrioles are eukaryotic organelles that template the formation of cilia and flagella, as well as organize the microtubule network and the mitotic spindle in animal cells. Centrioles have proximal-distal polarity and a 9-fold radial symmetry imparted by a likewise symmetrical central scaffold, the cartwheel. The spindle assembly abnormal protein 6 (SAS-6) self-assembles into 9-fold radially symmetric ring-shaped oligomers that stack via an unknown mechanism to form the cartwheel. Here, we uncover a homo-oligomerization interaction mediated by the coiled-coil domain of SAS-6. Crystallographic structures of Chlamydomonas reinhardtii SAS-6 coiled-coil complexes suggest this interaction is asymmetric, thereby imparting polarity to the cartwheel. Using a cryoelectron microscopy (cryo-EM) reconstitution assay, we demonstrate that amino acid substitutions disrupting this asymmetric association also impair SAS-6 ring stacking. Our work raises the possibility that the asymmetric interaction inherent to SAS-6 coiled-coil provides a polar element for cartwheel assembly, which may assist the establishment of the centriolar proximal-distal axis.
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Affiliation(s)
| | - Georgios N Hatzopoulos
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), 1005 Lausanne, Switzerland
| | - Pierre Gönczy
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), 1005 Lausanne, Switzerland.
| | - Ioannis Vakonakis
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK.
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6
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Tian Y, Yan Y, Fu J. Nine-fold symmetry of centriole: The joint efforts of its core proteins. Bioessays 2022; 44:e2100262. [PMID: 34997615 DOI: 10.1002/bies.202100262] [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: 11/07/2021] [Revised: 12/22/2021] [Accepted: 12/30/2021] [Indexed: 12/14/2022]
Abstract
The centriole is a widely conserved organelle required for the assembly of centrosomes, cilia, and flagella. Its striking feature - the nine-fold symmetrical structure, was discovered over 70 years ago by transmission electron microscopy, and since elaborated mostly by cryo-electron microscopy and super-resolution microscopy. Here, we review the discoveries that led to the current understanding of how the nine-fold symmetrical structure is built. We focus on the recent findings of the centriole structure in high resolution, its assembly pathways, and its nine-fold distributed components. We propose a model that the assembly of the nine-fold symmetrical centriole depends on the concerted efforts of its core proteins.
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Affiliation(s)
- Yuan Tian
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Yuxuan Yan
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Jingyan Fu
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
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7
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Abstract
Cilia are tail-like organelles responsible for motility, transportation, and sensory functions in eukaryotic cells. Cilia research has been providing multifaceted questions, attracting biologists of various areas and inducing interdisciplinary studies. In this chapter, we mainly focus on efforts to elucidate the molecular mechanism of ciliary beating motion, a field of research that has a long history and is still ongoing. We also overview topics closely related to the motility mechanism, such as ciliogenesis, cilia-related diseases, and sensory cilia. Subnanometer-scale to submillimeter-scale 3D imaging of the axoneme and the basal body resulted in a wide variety of insights into these questions.
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Affiliation(s)
- Takashi Ishikawa
- Department of Biology and Chemistry, Paul Scherrer Institute, Villigen, Switzerland.
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8
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Tian Y, Wei C, He J, Yan Y, Pang N, Fang X, Liang X, Fu J. Superresolution characterization of core centriole architecture. J Cell Biol 2021; 220:211748. [PMID: 33533934 PMCID: PMC7863704 DOI: 10.1083/jcb.202005103] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 11/29/2020] [Accepted: 01/06/2021] [Indexed: 12/31/2022] Open
Abstract
The centrosome is the main microtubule-organizing center in animal cells. It comprises of two centrioles and the surrounding pericentriolar material. Protein organization at the outer layer of the centriole and outward has been studied extensively; however, an overall picture of the protein architecture at the centriole core has been missing. Here we report a direct view of Drosophila centriolar proteins at ∼50-nm resolution. This reveals a Sas6 ring at the C-terminus, where it overlaps with the C-terminus of Cep135. The ninefold symmetrical pattern of Cep135 is further conveyed through Ana1-Asterless axes that extend past the microtubule wall from between the blades. Ana3 and Rcd4, whose termini are close to Cep135, are arranged in ninefold symmetry that does not match the above axes. During centriole biogenesis, Ana3 and Rcd4 are sequentially loaded on the newly formed centriole and are required for centriole-to-centrosome conversion through recruiting the Cep135-Ana1-Asterless complex. Together, our results provide a spatiotemporal map of the centriole core and implications of how the structure might be built.
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Affiliation(s)
- Yuan Tian
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Chenxi Wei
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Jianfeng He
- Tsinghua-Peking Joint Center for Life Sciences and Max Planck Partner Group, School of Life Sciences, Tsinghua University, Beijing, China
| | - Yuxuan Yan
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Nan Pang
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Xiaomin Fang
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Xin Liang
- Tsinghua-Peking Joint Center for Life Sciences and Max Planck Partner Group, School of Life Sciences, Tsinghua University, Beijing, China
| | - Jingyan Fu
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
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9
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Pereira SG, Dias Louro MA, Bettencourt-Dias M. Biophysical and Quantitative Principles of Centrosome Biogenesis and Structure. Annu Rev Cell Dev Biol 2021; 37:43-63. [PMID: 34314592 DOI: 10.1146/annurev-cellbio-120219-051400] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The centrosome is a main orchestrator of the animal cellular microtubule cytoskeleton. Dissecting its structure and assembly mechanisms has been a goal of cell biologists for over a century. In the last two decades, a good understanding of the molecular constituents of centrosomes has been achieved. Moreover, recent breakthroughs in electron and light microscopy techniques have enabled the inspection of the centrosome and the mapping of its components with unprecedented detail. However, we now need a profound and dynamic understanding of how these constituents interact in space and time. Here, we review the latest findings on the structural and molecular architecture of the centrosome and how its biogenesis is regulated, highlighting how biophysical techniques and principles as well as quantitative modeling are changing our understanding of this enigmatic cellular organelle. Expected final online publication date for the Annual Review of Cell and Developmental Biology, Volume 37 is October 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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10
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Vasquez-Limeta A, Loncarek J. Human centrosome organization and function in interphase and mitosis. Semin Cell Dev Biol 2021; 117:30-41. [PMID: 33836946 DOI: 10.1016/j.semcdb.2021.03.020] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 03/26/2021] [Accepted: 03/28/2021] [Indexed: 01/15/2023]
Abstract
Centrosomes were first described by Edouard Van Beneden and named and linked to chromosome segregation by Theodor Boveri around 1870. In the 1960-1980s, electron microscopy studies have revealed the remarkable ultrastructure of a centriole -- a nine-fold symmetrical microtubular assembly that resides within a centrosome and organizes it. Less than two decades ago, proteomics and genomic screens conducted in multiple species identified hundreds of centriole and centrosome core proteins and revealed the evolutionarily conserved nature of the centriole assembly pathway. And now, super resolution microscopy approaches and improvements in cryo-tomography are bringing an unparalleled nanoscale-detailed picture of the centriole and centrosome architecture. In this chapter, we summarize the current knowledge about the architecture of human centrioles. We discuss the structured organization of centrosome components in interphase, focusing on localization/function relationship. We discuss the process of centrosome maturation and mitotic spindle pole assembly in centriolar and acentriolar cells, emphasizing recent literature.
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Affiliation(s)
| | - Jadranka Loncarek
- Laboratory of Protein Dynamics and Signaling, NIH/NCI, Frederick 21702, MD, USA.
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11
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Maddi ER, Natesh R. Optimization strategies for expression and purification of soluble N-terminal domain of human centriolar protein SAS-6 in Escherichia coli. Protein Expr Purif 2021; 183:105856. [PMID: 33640460 DOI: 10.1016/j.pep.2021.105856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 02/04/2021] [Accepted: 02/18/2021] [Indexed: 11/19/2022]
Abstract
Spindle assembly abnormal protein 6 (SAS-6), a highly conserved centriolar protein, constitutes the center of the cartwheel assembly that scaffolds centrioles early in their biogenesis. Abnormalities in cartwheel assembly lead to chromosomal dysfunctions. The molecular structure of human SAS-6 (HsSAS-6) and cartwheel hub and how they direct centriole symmetry is unknown. No crystal structure of wildtype HsSAS-6 has been reported to date, since soluble recombinant partial/full-length HsSAS-6 expression and purification posed grand challenges. In the present study we have explored optimization of ten different N terminal SAS-6 fusion proteins expression in a variety of E. coli hosts. During optimization we have included some of the most commonly used purification tags: Histidine tag, maltose-binding protein (MBP), small ubiquitin-related modifier (SUMO) tag and modified MBP tag with surface entropy reduction mutations. We demonstrate several levels of tag assisted solubility and stable expression strategies. We find that the MBP tag accompanied by Surface Entropy Reduction mutations (MBP/SER) in a fixed arm approach rescues the folded SAS-6N protein with significantly improved solubility. This expression of HsSAS-6N in E. coli Rosetta DE3 pLysS expression strain gave rise to high protein expression yielding around 6.0-11.5 mg of soluble protein per liter of growth culture.
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Affiliation(s)
- Eswar Reddy Maddi
- School of Biology, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram, 695551, Kerala, India
| | - Ramanathan Natesh
- School of Biology, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram, 695551, Kerala, India.
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12
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LeGuennec M, Klena N, Aeschlimann G, Hamel V, Guichard P. Overview of the centriole architecture. Curr Opin Struct Biol 2020; 66:58-65. [PMID: 33176264 DOI: 10.1016/j.sbi.2020.09.015] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 09/25/2020] [Accepted: 09/28/2020] [Indexed: 12/12/2022]
Abstract
The centriole is a magnificent molecular assembly of several giga-daltons, one of the largest of the eukaryotic cell, and whose atomic structure remains unsolved to date. However, numerous electron microscopy, cryo-tomography, and super-resolution studies now make it possible to establish a global architectural view of it with its different sub-regions. These analyses broaden our understanding by providing additional informations to cell biology and structural biology approaches. In this review, we describe current knowledge on the overall organization of the centriole. We will highlight each sub-structural element, their differences between species and their putative protein composition. We will conclude on the current limitations that still take us away from a complete atomic view of the centriole architecture.
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Affiliation(s)
- Maeva LeGuennec
- University of Geneva, Department of Cell Biology, Sciences III, Geneva, Switzerland
| | - Nikolai Klena
- University of Geneva, Department of Cell Biology, Sciences III, Geneva, Switzerland
| | - Gabriel Aeschlimann
- Ribosome Studio Aeschlimann, Einsiedlerstrasse 6, Oberrieden, 8942, Switzerland
| | - Virginie Hamel
- University of Geneva, Department of Cell Biology, Sciences III, Geneva, Switzerland.
| | - Paul Guichard
- University of Geneva, Department of Cell Biology, Sciences III, Geneva, Switzerland.
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13
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Principal Postulates of Centrosomal Biology. Version 2020. Cells 2020; 9:cells9102156. [PMID: 32987651 PMCID: PMC7598677 DOI: 10.3390/cells9102156] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 09/10/2020] [Accepted: 09/21/2020] [Indexed: 12/13/2022] Open
Abstract
The centrosome, which consists of two centrioles surrounded by pericentriolar material, is a unique structure that has retained its main features in organisms of various taxonomic groups from unicellular algae to mammals over one billion years of evolution. In addition to the most noticeable function of organizing the microtubule system in mitosis and interphase, the centrosome performs many other cell functions. In particular, centrioles are the basis for the formation of sensitive primary cilia and motile cilia and flagella. Another principal function of centrosomes is the concentration in one place of regulatory proteins responsible for the cell's progression along the cell cycle. Despite the existing exceptions, the functioning of the centrosome is subject to general principles, which are discussed in this review.
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14
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Klena N, Le Guennec M, Tassin AM, van den Hoek H, Erdmann PS, Schaffer M, Geimer S, Aeschlimann G, Kovacik L, Sadian Y, Goldie KN, Stahlberg H, Engel BD, Hamel V, Guichard P. Architecture of the centriole cartwheel-containing region revealed by cryo-electron tomography. EMBO J 2020; 39:e106246. [PMID: 32954513 PMCID: PMC7667884 DOI: 10.15252/embj.2020106246] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 08/20/2020] [Accepted: 08/24/2020] [Indexed: 11/09/2022] Open
Abstract
Centrioles are evolutionarily conserved barrels of microtubule triplets that form the core of the centrosome and the base of the cilium. While the crucial role of the proximal region in centriole biogenesis has been well documented, its native architecture and evolutionary conservation remain relatively unexplored. Here, using cryo-electron tomography of centrioles from four evolutionarily distant species, we report on the architectural diversity of the centriole's proximal cartwheel-bearing region. Our work reveals that the cartwheel central hub is constructed from a stack of paired rings with cartwheel inner densities inside. In both Paramecium and Chlamydomonas, the repeating structural unit of the cartwheel has a periodicity of 25 nm and consists of three ring pairs, with 6 radial spokes emanating and merging into a single bundle that connects to the microtubule triplet via the D2-rod and the pinhead. Finally, we identified that the cartwheel is indirectly connected to the A-C linker through the triplet base structure extending from the pinhead. Together, our work provides unprecedented evolutionary insights into the architecture of the centriole proximal region, which underlies centriole biogenesis.
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Affiliation(s)
- Nikolai Klena
- Department of Cell Biology, University of Geneva, Sciences III, Geneva, Switzerland
| | - Maeva Le Guennec
- Department of Cell Biology, University of Geneva, Sciences III, Geneva, Switzerland
| | - Anne-Marie Tassin
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris Sud, Université Paris-Saclay, Gif sur Yvette, France
| | - Hugo van den Hoek
- Helmholtz Pioneer Campus, Helmholtz Zentrum München, Neuherberg, Germany.,Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Philipp S Erdmann
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Miroslava Schaffer
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Stefan Geimer
- Department of Cell Biology and Electron Microscopy, Universität Bayreuth, Bayreuth, Germany
| | | | - Lubomir Kovacik
- Center for Cellular Imaging and NanoAnalytics (C-CINA), Biozentrum, University of Basel, Basel, Switzerland
| | - Yashar Sadian
- Bioimaging and Cryogenic Center, University of Geneva, Geneva, Switzerland
| | - Kenneth N Goldie
- Center for Cellular Imaging and NanoAnalytics (C-CINA), Biozentrum, University of Basel, Basel, Switzerland
| | - Henning Stahlberg
- Center for Cellular Imaging and NanoAnalytics (C-CINA), Biozentrum, University of Basel, Basel, Switzerland
| | - Benjamin D Engel
- Helmholtz Pioneer Campus, Helmholtz Zentrum München, Neuherberg, Germany.,Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, Martinsried, Germany.,Department of Chemistry, Technical University of Munich, Garching, Germany
| | - Virginie Hamel
- Department of Cell Biology, University of Geneva, Sciences III, Geneva, Switzerland
| | - Paul Guichard
- Department of Cell Biology, University of Geneva, Sciences III, Geneva, Switzerland
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15
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Nazarov S, Bezler A, Hatzopoulos GN, Nemčíková Villímová V, Demurtas D, Le Guennec M, Guichard P, Gönczy P. Novel features of centriole polarity and cartwheel stacking revealed by cryo-tomography. EMBO J 2020; 39:e106249. [PMID: 32954505 PMCID: PMC7667878 DOI: 10.15252/embj.2020106249] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 08/11/2020] [Accepted: 08/21/2020] [Indexed: 11/25/2022] Open
Abstract
Centrioles are polarized microtubule‐based organelles that seed the formation of cilia, and which assemble from a cartwheel containing stacked ring oligomers of SAS‐6 proteins. A cryo‐tomography map of centrioles from the termite flagellate Trichonympha spp. was obtained previously, but higher resolution analysis is likely to reveal novel features. Using sub‐tomogram averaging (STA) in T. spp. and Trichonympha agilis, we delineate the architecture of centriolar microtubules, pinhead, and A‐C linker. Moreover, we report ~25 Å resolution maps of the central cartwheel, revealing notably polarized cartwheel inner densities (CID). Furthermore, STA of centrioles from the distant flagellate Teranympha mirabilis uncovers similar cartwheel architecture and a distinct filamentous CID. Fitting the CrSAS‐6 crystal structure into the flagellate maps and analyzing cartwheels generated in vitro indicate that SAS‐6 rings can directly stack onto one another in two alternating configurations: with a slight rotational offset and in register. Overall, improved STA maps in three flagellates enabled us to unravel novel architectural features, including of centriole polarity and cartwheel stacking, thus setting the stage for an accelerated elucidation of underlying assembly mechanisms.
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Affiliation(s)
- Sergey Nazarov
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), Lausanne, Switzerland.,Interdisciplinary Centre for Electron Microscopy (CIME), Swiss Federal Institute of Technology Lausanne (EPFL), Lausanne, Switzerland
| | - Alexandra Bezler
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), Lausanne, Switzerland
| | - Georgios N Hatzopoulos
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), Lausanne, Switzerland
| | - Veronika Nemčíková Villímová
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), Lausanne, Switzerland
| | - Davide Demurtas
- Interdisciplinary Centre for Electron Microscopy (CIME), Swiss Federal Institute of Technology Lausanne (EPFL), Lausanne, Switzerland
| | - Maeva Le Guennec
- Department of Cell Biology, University of Geneva, Sciences III, Geneva, Switzerland
| | - Paul Guichard
- Department of Cell Biology, University of Geneva, Sciences III, Geneva, Switzerland
| | - Pierre Gönczy
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), Lausanne, Switzerland
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16
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Vakonakis I. The centriolar cartwheel structure: symmetric, stacked, and polarized. Curr Opin Struct Biol 2020; 66:1-7. [PMID: 32956907 DOI: 10.1016/j.sbi.2020.08.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 08/24/2020] [Accepted: 08/25/2020] [Indexed: 11/29/2022]
Abstract
An accurate centriolar structure is crucial for organelle function, necessitating the existence of molecular mechanisms for the tight control of centriole assembly. Formation of an initial scaffold, the cartwheel, assists the correct placement of centriolar proteins during assembly and templates key structural parameters of the organelle. Past work illustrated how cartwheel and centriolar symmetry are linked, and grounded organelle symmetry and diameter to the properties of the centriolar protein SAS-6. However, questions remained over how centriole polarity and length are controlled. Recent advances in resolving cartwheel structure and cell biology showed that these assemblies are polarized and that their length is under the control of a homeostatic mechanism. These cartwheel properties may, in turn, influence the centriolar polarity and length.
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Affiliation(s)
- Ioannis Vakonakis
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, United Kingdom.
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17
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Greenan GA, Vale RD, Agard DA. Electron cryotomography of intact motile cilia defines the basal body to axoneme transition. J Cell Biol 2020; 219:133537. [PMID: 31874113 PMCID: PMC7039205 DOI: 10.1083/jcb.201907060] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 10/23/2019] [Accepted: 10/28/2019] [Indexed: 12/16/2022] Open
Abstract
Greenan et al. use electron cryotomography on intact motile cilia to elucidate how basal bodies template the formation of motile axonemes. Cells use motile cilia to generate force in the extracellular space. The structure of a cilium can be classified into three subdomains: the intracellular basal body (BB) that templates cilium formation, the extracellular axoneme that generates force, and the transition zone (TZ) that bridges them. While the BB is composed of triplet microtubules (TMTs), the axoneme is composed of doublet microtubules (DMTs), meaning the cilium must convert between different microtubule geometries. Here, we performed electron cryotomography to define this conversion, and our reconstructions reveal identifying structural features of the BB, TZ, and axoneme. Each region is distinct in terms of microtubule number and geometry, microtubule inner proteins, and microtubule linkers. TMT to DMT conversion occurs within the BB, and microtubule geometry changes to axonemal by the end of the TZ, followed by the addition of axoneme-specific components essential for cilium motility. Our results provide the highest-resolution images of the motile cilium to date and reveal how BBs template axonemes.
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Affiliation(s)
- Garrett A Greenan
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA.,Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA.,The Howard Hughes Medical Institute, Chevy Chase, MD
| | - Ronald D Vale
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA.,The Howard Hughes Medical Institute, Chevy Chase, MD
| | - David A Agard
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA.,The Howard Hughes Medical Institute, Chevy Chase, MD
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18
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Cilia and centrosomes: Ultrastructural and mechanical perspectives. Semin Cell Dev Biol 2020; 110:61-69. [PMID: 32307225 DOI: 10.1016/j.semcdb.2020.03.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 03/12/2020] [Accepted: 03/21/2020] [Indexed: 11/20/2022]
Abstract
Cilia and centrosomes of eukaryotic cells play important roles in cell movement, fluid transport, extracellular sensing, and chromosome division. The physiological functions of cilia and centrosomes are generated by their dynamics, motions, and forces controlled by the physical, chemical, and biological environments. How an individual cilium achieves its beat pattern and induces fluid flow is governed by its ultrastructure as well as the coordination of associated molecular motors. Thus, a bottom-up understanding of the physiological functions of cilia and centrosomes from the molecular to tissue levels is required. Correlations between the structure and motion can be understood in terms of mechanics. This review first focuses on cilia and centrosomes at the molecular level, introducing their ultrastructure. We then shift to the organelle level and introduce the kinematics and mechanics of cilia and centrosomes. Next, at the tissue level, we introduce nodal ciliary dynamics and nodal flow, which play crucial roles in the organogenetic process of left-right asymmetry. We also introduce respiratory ciliary dynamics and mucous flow, which are critical for protecting the epithelium from drying and exposure to harmful particles and viruses, i.e., respiratory clearance function. Finally, we discuss the future research directions in this field.
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19
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Kelleher FC, Kroes J, Lewin J. Targeting the centrosome and polo-like kinase 4 in osteosarcoma. Carcinogenesis 2020; 40:493-499. [PMID: 30508038 DOI: 10.1093/carcin/bgy175] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 11/22/2018] [Accepted: 11/29/2018] [Indexed: 12/26/2022] Open
Abstract
It has been historically uncertain if extra centrosomes are a cause or consequence of tumorigenesis. Experiments have recently established that overexpression of polo-like kinase 4 (PLK4) promotes centrosome amplification with consequential promotion of cellular aneuploidy. Furthermore, centrosome amplification drives spontaneous tumorigenesis in mice. Tissues lacking normal functional p53 tolerate extra centrosomes, whereas p53 proficient tissues initiate proliferative arrest in this circumstance. Extra centrosomes trigger activation of the multi-protein PIDDosome complex, with Caspase-2 effecting cleavage of the p53-negative regulator mouse double minute 2, consequent stabilization of p53 and p21-dependent arrest of the cell cycle. The co-occurrence of cellular aneuploidy, complex chromosomal rearrangements and p53 dysfunction is a striking feature of some osteosarcomas. It is postulated that small-molecule PLK4 inhibitors such as CFI-400945, which are in development, may have utility in osteosarcoma given these findings.
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Affiliation(s)
- Fergal C Kelleher
- Department of Medical Oncology, St. James Hospital, Dublin, Ireland
- School of Medicine, Trinity College Dublin, Dublin, Ireland
| | - Jeska Kroes
- Department of Medical Oncology, St. James Hospital, Dublin, Ireland
| | - Jeremy Lewin
- Department of Medical Oncology, Peter MacCallum Cancer Center, Melbourne, Victoria, Australia
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20
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Abstract
AbstractCentrosome is the main microtubule-organizing center in most animal cells. Its core structure, centriole, also assembles cilia and flagella that have important sensing and motility functions. Centrosome has long been recognized as a highly conserved organelle in eukaryotic species. Through electron microscopy, its ultrastructure was revealed to contain a beautiful nine-symmetrical core 60 years ago, yet its molecular basis has only been unraveled in the past two decades. The emergence of super-resolution microscopy allows us to explore the insides of a centrosome, which is smaller than the diffraction limit of light. Super-resolution microscopy also enables the compartmentation of centrosome proteins into different zones and the identification of their molecular interactions and functions. This paper compiles the centrosome architecture knowledge that has been revealed in recent years and highlights the power of several super-resolution techniques.
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21
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Cep131 overexpression promotes centrosome amplification and colon cancer progression by regulating Plk4 stability. Cell Death Dis 2019; 10:570. [PMID: 31358734 PMCID: PMC6662699 DOI: 10.1038/s41419-019-1778-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 04/18/2019] [Accepted: 04/23/2019] [Indexed: 12/22/2022]
Abstract
The initiation of centrosome duplication is regulated by the Plk4/STIL/hsSAS-6 axis; however, the involvement of other centrosomal proteins in this process remains unclear. In this study, we demonstrate that Cep131 physically interacts with Plk4 following phosphorylation of residues S21 and T205. Localizing at the centriole, phosphorylated Cep131 has an increased capability to interact with STIL, leading to further activation and stabilization of Plk4 for initiating centrosome duplication. Moreover, we found that Cep131 overexpression resulted in centrosome amplification by excessive recruitment of STIL to the centriole and subsequent stabilization of Plk4, contributing to centrosome amplification. The xenograft mouse model also showed that both centrosome amplification and colon cancer growth were significantly increased by Cep131 overexpression. These findings demonstrate that Cep131 is a novel substrate of Plk4, and that phosphorylation or dysregulated Cep131 overexpression promotes Plk4 stabilization and therefore centrosome amplification, establishing a perspective in understanding a relationship between centrosome amplification and cancer development.
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22
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Busselez J, Chichón FJ, Rodríguez MJ, Alpízar A, Gharbi SI, Franch M, Melero R, Paradela A, Carrascosa JL, Carazo JM. Cryo-Electron Tomography and Proteomics studies of centrosomes from differentiated quiescent thymocytes. Sci Rep 2019; 9:7187. [PMID: 31076588 PMCID: PMC6510768 DOI: 10.1038/s41598-019-43338-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 04/08/2019] [Indexed: 02/02/2023] Open
Abstract
We have used cryo Electron Tomography, proteomics and immunolabeling to study centrosomes isolated from the young lamb thymus, an efficient source of quiescent differentiated cells. We compared the proteome of thymocyte centrosomes to data published for KE37 cells, focusing on proteins associated with centriole disengagement and centrosome separation. The data obtained enhances our understanding of the protein system joining the centrioles, a system comprised of a branched network of fibers linked to an apparently amorphous density that was partially characterized here. A number of proteins were localized to the amorphous density by immunolabeling (C-NAP1, cohesin SMC1, condensin SMC4 and NCAPD2), yet not DNA. In conjuction, these data not only extend our understanding of centrosomes but they will help refine the model that focus on the protein system associated with the centriolar junction.
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Affiliation(s)
- Johan Busselez
- Centro Nacional de Biotecnologia (CNB-CSIC), Darwin 3, Campus de Cantoblanco 28049, Madrid, Spain. .,Institut de Génétique et de Biologie Moléculaire et Cellulaire, 1 Rue Laurent Fries, 67400, Illkirch-Graffenstaden, France.
| | - Francisco Javier Chichón
- Centro Nacional de Biotecnologia (CNB-CSIC), Darwin 3, Campus de Cantoblanco 28049, Madrid, Spain
| | - Maria Josefa Rodríguez
- Centro Nacional de Biotecnologia (CNB-CSIC), Darwin 3, Campus de Cantoblanco 28049, Madrid, Spain
| | - Adan Alpízar
- Centro Nacional de Biotecnologia (CNB-CSIC), Darwin 3, Campus de Cantoblanco 28049, Madrid, Spain
| | - Séverine Isabelle Gharbi
- Centro Nacional de Biotecnologia (CNB-CSIC), Darwin 3, Campus de Cantoblanco 28049, Madrid, Spain
| | - Mònica Franch
- Centro Nacional de Biotecnologia (CNB-CSIC), Darwin 3, Campus de Cantoblanco 28049, Madrid, Spain
| | - Roberto Melero
- Centro Nacional de Biotecnologia (CNB-CSIC), Darwin 3, Campus de Cantoblanco 28049, Madrid, Spain
| | - Alberto Paradela
- Centro Nacional de Biotecnologia (CNB-CSIC), Darwin 3, Campus de Cantoblanco 28049, Madrid, Spain
| | - José L Carrascosa
- Centro Nacional de Biotecnologia (CNB-CSIC), Darwin 3, Campus de Cantoblanco 28049, Madrid, Spain
| | - José-Maria Carazo
- Centro Nacional de Biotecnologia (CNB-CSIC), Darwin 3, Campus de Cantoblanco 28049, Madrid, Spain.
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23
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Busch JMC, Erat MC, Blank ID, Musgaard M, Biggin PC, Vakonakis I. A dynamically interacting flexible loop assists oligomerisation of the Caenorhabditis elegans centriolar protein SAS-6. Sci Rep 2019; 9:3526. [PMID: 30837637 PMCID: PMC6401066 DOI: 10.1038/s41598-019-40294-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Accepted: 02/11/2019] [Indexed: 01/12/2023] Open
Abstract
Centrioles are conserved organelles fundamental for the organisation of microtubules in animal cells. Oligomerisation of the spindle assembly abnormal protein 6 (SAS-6) is an essential step in the centriole assembly process and may act as trigger for the formation of these organelles. SAS-6 oligomerisation is driven by two independent interfaces, comprising an extended coiled coil and a dimeric N-terminal globular domain. However, how SAS-6 oligomerisation is controlled remains unclear. Here, we show that in the Caenorhabditis elegans SAS-6, a segment of the N-terminal globular domain, unresolved in crystallographic structures, comprises a flexible loop that assists SAS-6 oligomerisation. Atomistic molecular dynamics simulations and nuclear magnetic resonance experiments suggest that transient interactions of this loop across the N-terminal dimerisation interface stabilise the SAS-6 oligomer. We discuss the possibilities presented by such flexible SAS-6 segments for the control of centriole formation.
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Affiliation(s)
- Julia M C Busch
- University of Oxford, Department of Biochemistry, Oxford, OX1 3QU, United Kingdom
| | - Michèle C Erat
- University of Oxford, Department of Biochemistry, Oxford, OX1 3QU, United Kingdom.,University of Warwick, Mathematical Institute, Coventry, CV4 7AL, United Kingdom
| | - Iris D Blank
- University of Oxford, Department of Biochemistry, Oxford, OX1 3QU, United Kingdom
| | - Maria Musgaard
- University of Oxford, Department of Biochemistry, Oxford, OX1 3QU, United Kingdom.,University of Ottawa, Department of Chemistry and Biomolecular Sciences, Ottawa, ON, K1N 6N5, Canada
| | - Philip C Biggin
- University of Oxford, Department of Biochemistry, Oxford, OX1 3QU, United Kingdom
| | - Ioannis Vakonakis
- University of Oxford, Department of Biochemistry, Oxford, OX1 3QU, United Kingdom.
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24
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Dallai R, Mercati D, Lino-Neto J, Dias G, Folly C, Lupetti P. The peculiar structure of the flagellar axoneme in Coccinellidae (Insecta-Coleoptera). ARTHROPOD STRUCTURE & DEVELOPMENT 2019; 49:50-61. [PMID: 30445115 DOI: 10.1016/j.asd.2018.11.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 11/06/2018] [Accepted: 11/09/2018] [Indexed: 06/09/2023]
Abstract
The ultrastructure of the complex organisation of the spermatozoa in Harmonia axyridis and Adalia decempunctata (Coccinellidae) was studied, with particular emphasis on the origin of the anterior shifting of the axonemal structure, which becomes parallel to the nucleus in the sperm flagellum. In studying the spermiogenesis, a centriolar remodelling was observed with the long centriole, present in the early spermatids, transformed in the spermatozoa into an exceptionally long and narrowed basal body (about 0.16 × 3.5-4.0 μm long) displaying a 9 + 0 microtubular pattern in the proximal part and a 9 + 2 pattern in the following part; this is a characteristic not observed in any other pterygotan insect. The sperm also have a very long acrosome surrounded by a dense layer of material extending along the whole basal body. These two uncommon features were discussed in the light of sperm movement.
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Affiliation(s)
- Romano Dallai
- Dipartimento Scienze della Vita, Università degli Studi di Siena, Via Aldo Moro 2, 53100 Siena, Italy.
| | - David Mercati
- Dipartimento Scienze della Vita, Università degli Studi di Siena, Via Aldo Moro 2, 53100 Siena, Italy.
| | - José Lino-Neto
- Departamento de Biologia Geral, Universidade Federal de Viçosa, 36570-900 Viçosa, Minas Gerais, Brazil.
| | - Glenda Dias
- Departamento de Biologia Geral, Universidade Federal de Viçosa, 36570-900 Viçosa, Minas Gerais, Brazil.
| | - Camilla Folly
- Departamento de Biologia Geral, Universidade Federal de Viçosa, 36570-900 Viçosa, Minas Gerais, Brazil.
| | - Pietro Lupetti
- Dipartimento Scienze della Vita, Università degli Studi di Siena, Via Aldo Moro 2, 53100 Siena, Italy.
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25
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Abstract
The centriole organelle consists of microtubules (MTs) that exhibit a striking 9-fold radial symmetry. Centrioles play fundamental roles across eukaryotes, notably in cell signaling, motility and division. In this Cell Science at a Glance article and accompanying poster, we cover the cellular life cycle of this organelle - from assembly to disappearance - focusing on human centrioles. The journey begins at the end of mitosis when centriole pairs disengage and the newly formed centrioles mature to begin a new duplication cycle. Selection of a single site of procentriole emergence through focusing of polo-like kinase 4 (PLK4) and the resulting assembly of spindle assembly abnormal protein 6 (SAS-6) into a cartwheel element are evoked next. Subsequently, we cover the recruitment of peripheral components that include the pinhead structure, MTs and the MT-connecting A-C linker. The function of centrioles in recruiting pericentriolar material (PCM) and in forming the template of the axoneme are then introduced, followed by a mention of circumstances in which centrioles form de novo or are eliminated.
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Affiliation(s)
- Pierre Gönczy
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology (EPFL), CH-1015 Lausanne, Switzerland
| | - Georgios N Hatzopoulos
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology (EPFL), CH-1015 Lausanne, Switzerland
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26
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Li S, Fernandez JJ, Marshall WF, Agard DA. Electron cryo-tomography provides insight into procentriole architecture and assembly mechanism. eLife 2019; 8:43434. [PMID: 30741631 PMCID: PMC6384029 DOI: 10.7554/elife.43434] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Accepted: 02/10/2019] [Indexed: 01/03/2023] Open
Abstract
Centriole is an essential structure with multiple functions in cellular processes. Centriole biogenesis and homeostasis is tightly regulated. Using electron cryo-tomography (cryoET) we present the structure of procentrioles from Chlamydomonas reinhardtii. We identified a set of non-tubulin components attached to the triplet microtubule (MT), many are at the junctions of tubules likely to reinforce the triplet. We describe structure of the A-C linker that bridges neighboring triplets. The structure infers that POC1 is likely an integral component of A-C linker. Its conserved WD40 β-propeller domain provides attachment sites for other A-C linker components. The twist of A-C linker results in an iris diaphragm-like motion of the triplets in the longitudinal direction of procentriole. Finally, we identified two assembly intermediates at the growing ends of procentriole allowing us to propose a model for the procentriole assembly. Our results provide a comprehensive structural framework for understanding the molecular mechanisms underpinning procentriole biogenesis and assembly.
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Affiliation(s)
- Sam Li
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, United States
| | | | - Wallace F Marshall
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, United States
| | - David A Agard
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, United States.,Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, United States
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27
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Abstract
The centriole is an ancient microtubule-based organelle with a conserved nine-fold symmetry. Centrioles form the core of centrosomes, which organize the interphase microtubule cytoskeleton of most animal cells and form the poles of the mitotic spindle. Centrioles can also be modified to form basal bodies, which template the formation of cilia and play central roles in cellular signaling, fluid movement, and locomotion. In this review, we discuss developments in our understanding of the biogenesis of centrioles and cilia and the regulatory controls that govern their structure and number. We also discuss how defects in these processes contribute to a spectrum of human diseases and how new technologies have expanded our understanding of centriole and cilium biology, revealing exciting avenues for future exploration.
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Affiliation(s)
- David K Breslow
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, Connecticut 06511, USA;
| | - Andrew J Holland
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA;
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28
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Yoshiba S, Tsuchiya Y, Ohta M, Gupta A, Shiratsuchi G, Nozaki Y, Ashikawa T, Fujiwara T, Natsume T, Kanemaki M, Kitagawa D. HsSAS-6-dependent cartwheel assembly ensures stabilization of centriole intermediates. J Cell Sci 2019; 132:jcs.217521. [DOI: 10.1242/jcs.217521] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 05/28/2019] [Indexed: 12/23/2022] Open
Abstract
At the onset of procentriole formation, a structure called the cartwheel is formed adjacent to the pre-existing centriole. SAS-6 proteins are thought to constitute the hub of the cartwheel structure. However, the exact function of the cartwheel in the process of centriole formation has not been well characterized. In this study, we focused on the functions of human SAS-6 (HsSAS-6). Using in vitro reconstitution with recombinant HsSAS-6, we first observed its conserved molecular property forming the central part of the cartwheel structure. Furthermore, we uncovered critical functions of HsSAS-6 using a combination of an auxin-inducible SAS-6-degron system and super-resolution microscopy in human cells. Our results demonstrate that the HsSAS-6 is required not only for the initiation of centriole formation, but also for the stabilization of centriole intermediates. Moreover, after procentriole formation, HsSAS-6 is necessary for limiting Plk4 accumulation at the centrioles and thereby suppressing the formation of potential sites for extra procentrioles. Overall, these findings illustrate the conserved and fundamental functions of the cartwheel in centriole duplication.
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Affiliation(s)
- Satoko Yoshiba
- Division of Centrosome Biology, Department of Molecular Genetics, National Institute of Genetics, Mishima, Shizuoka, Japan
- Current affiliation: Laboratory of Physiological Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Japan
| | - Yuki Tsuchiya
- Division of Centrosome Biology, Department of Molecular Genetics, National Institute of Genetics, Mishima, Shizuoka, Japan
- Department of Genetics, School of Life Science, SOKENDAI, Mishima, Shizuoka 411-8540, Japan
| | - Midori Ohta
- Division of Centrosome Biology, Department of Molecular Genetics, National Institute of Genetics, Mishima, Shizuoka, Japan
| | - Akshari Gupta
- Division of Centrosome Biology, Department of Molecular Genetics, National Institute of Genetics, Mishima, Shizuoka, Japan
- Department of Genetics, School of Life Science, SOKENDAI, Mishima, Shizuoka 411-8540, Japan
| | - Gen Shiratsuchi
- Division of Centrosome Biology, Department of Molecular Genetics, National Institute of Genetics, Mishima, Shizuoka, Japan
| | - Yuka Nozaki
- Division of Centrosome Biology, Department of Molecular Genetics, National Institute of Genetics, Mishima, Shizuoka, Japan
| | - Tomoko Ashikawa
- Division of Centrosome Biology, Department of Molecular Genetics, National Institute of Genetics, Mishima, Shizuoka, Japan
| | - Takahiro Fujiwara
- Center for Meso-Bio Single-Molecule Imaging (CeMI), Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University, Kyoto, Japan
| | - Toyoaki Natsume
- Division of Molecular Cell Engineering, Department of Molecular Genetics, National Institute of Genetics, Mishima, Shizuoka, Japan
| | - Masato Kanemaki
- Division of Molecular Cell Engineering, Department of Molecular Genetics, National Institute of Genetics, Mishima, Shizuoka, Japan
| | - Daiju Kitagawa
- Division of Centrosome Biology, Department of Molecular Genetics, National Institute of Genetics, Mishima, Shizuoka, Japan
- Department of Genetics, School of Life Science, SOKENDAI, Mishima, Shizuoka 411-8540, Japan
- Current affiliation: Laboratory of Physiological Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Japan
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29
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Avidor-Reiss T, Turner K. The Evolution of Centriole Structure: Heterochrony, Neoteny, and Hypermorphosis. Results Probl Cell Differ 2019; 67:3-15. [PMID: 31435789 DOI: 10.1007/978-3-030-23173-6_1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Centrioles are subcellular organelles that were present in the last eukaryotic common ancestor, where the centriole's ancestral role was to form cilia. Centrioles have maintained a remarkably conserved structure in eukaryotes that have cilia, while groups that lack cilia have lost their centrioles, highlighting the structure-function relationship that exists between the centriole and the cilium. In contrast, animal sperm cells, a ciliated cell, exhibit remarkable structural diversity in the centriole. Understanding how this structural diversity evolved may provide insight into centriole assembly and function, as well as their unique role in sperm. Here, we apply concepts used in the study of the evolution of animal morphology to gain insight into the evolution of centriole structure. We propose that centrioles with an atypical structure form because of changes in the timing of centriole assembly events, which can be described as centriolar "heterochrony." Atypical centrioles of insects and mammals appear to have evolved through different types of heterochrony. Here, we discuss two particular types of heterochrony: neoteny and hypermorphosis. The centriole assembly of insect sperm cells exhibits the retention of "juvenile" centriole structure, which can be described as centriolar "neoteny." Mammalian sperm cells have an extended centriole assembly program through the addition of novel steps such as centrosome reduction and centriole remodeling to form atypical centrioles, a form of centriole "hypermorphosis." Overall, centriole heterochrony appears to be a common mechanism for the development of the atypical centriole during the evolution of centriole assembly of various animals' sperm.
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Affiliation(s)
- Tomer Avidor-Reiss
- Department of Biological Sciences, University of Toledo, Toledo, OH, USA.
| | - Katerina Turner
- Department of Biological Sciences, University of Toledo, Toledo, OH, USA
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30
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Stoddard D, Zhao Y, Bayless BA, Gui L, Louka P, Dave D, Suryawanshi S, Tomasi RFX, Dupuis-Williams P, Baroud CN, Gaertig J, Winey M, Nicastro D. Tetrahymena RIB72A and RIB72B are microtubule inner proteins in the ciliary doublet microtubules. Mol Biol Cell 2018; 29:2566-2577. [PMID: 30133348 PMCID: PMC6254578 DOI: 10.1091/mbc.e18-06-0405] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Doublet and triplet microtubules are essential and highly stable core structures of centrioles, basal bodies, cilia, and flagella. In contrast to dynamic cytoplasmic microtubules, their luminal surface is coated with regularly arranged microtubule inner proteins (MIPs). However, the protein composition and biological function(s) of MIPs remain poorly understood. Using genetic, biochemical, and imaging techniques, we identified Tetrahymena RIB72A and RIB72B proteins as ciliary MIPs. Fluorescence imaging of tagged RIB72A and RIB72B showed that both proteins colocalize to Tetrahymena cilia and basal bodies but assemble independently. Cryoelectron tomography of RIB72A and/or RIB72B knockout strains revealed major structural defects in the ciliary A-tubule involving MIP1, MIP4, and MIP6 structures. The defects of individual mutants were complementary in the double mutant. All mutants had reduced swimming speed and ciliary beat frequencies, and high-speed video imaging revealed abnormal highly curved cilia during power stroke. Our results show that RIB72A and RIB72B are crucial for the structural assembly of ciliary A-tubule MIPs and are important for proper ciliary motility.
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Affiliation(s)
- Daniel Stoddard
- Department of Biology, Rosenstiel Basic Medical Sciences Research Center, Brandeis University, Waltham, MA 02453.,Departments of Cell Biology and Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Ying Zhao
- Department of Molecular, Cellular & Developmental Biology University of Colorado Boulder, Boulder, CO 80309
| | - Brian A Bayless
- Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA 95616
| | - Long Gui
- Departments of Cell Biology and Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Panagiota Louka
- Department of Cellular Biology, University of Georgia, Athens, GA 30602
| | - Drashti Dave
- Department of Cellular Biology, University of Georgia, Athens, GA 30602
| | - Swati Suryawanshi
- Department of Cellular Biology, University of Georgia, Athens, GA 30602
| | - Raphaël F-X Tomasi
- Department of Mechanics, LadHyX, CNRS and Ecole Polytechnique, 91128 Palaiseau Cedex, France.,Physical Microfluidics and Bioengineering, Department of Genomes and Genetics, Institut Pasteur, 75015 Paris, France
| | - Pascale Dupuis-Williams
- UMR-S 1174 Inserm, Universite Paris-Sud, 91405 Orsay Cedex, France.,Ecole Supérieure de Physique et de Chimie Industrielles ParisTech, 75005 Paris, France
| | - Charles N Baroud
- Department of Mechanics, LadHyX, CNRS and Ecole Polytechnique, 91128 Palaiseau Cedex, France.,Physical Microfluidics and Bioengineering, Department of Genomes and Genetics, Institut Pasteur, 75015 Paris, France
| | - Jacek Gaertig
- Department of Cellular Biology, University of Georgia, Athens, GA 30602
| | - Mark Winey
- Department of Molecular, Cellular & Developmental Biology University of Colorado Boulder, Boulder, CO 80309.,Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA 95616
| | - Daniela Nicastro
- Department of Biology, Rosenstiel Basic Medical Sciences Research Center, Brandeis University, Waltham, MA 02453.,Departments of Cell Biology and Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390
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31
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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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32
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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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33
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Nigg EA, Holland AJ. Once and only once: mechanisms of centriole duplication and their deregulation in disease. Nat Rev Mol Cell Biol 2018; 19:297-312. [PMID: 29363672 PMCID: PMC5969912 DOI: 10.1038/nrm.2017.127] [Citation(s) in RCA: 298] [Impact Index Per Article: 49.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Centrioles are conserved microtubule-based organelles that form the core of the centrosome and act as templates for the formation of cilia and flagella. Centrioles have important roles in most microtubule-related processes, including motility, cell division and cell signalling. To coordinate these diverse cellular processes, centriole number must be tightly controlled. In cycling cells, one new centriole is formed next to each pre-existing centriole in every cell cycle. Advances in imaging, proteomics, structural biology and genome editing have revealed new insights into centriole biogenesis, how centriole numbers are controlled and how alterations in these processes contribute to diseases such as cancer and neurodevelopmental disorders. Moreover, recent work has uncovered the existence of surveillance pathways that limit the proliferation of cells with numerical centriole aberrations. Owing to this progress, we now have a better understanding of the molecular mechanisms governing centriole biogenesis, opening up new possibilities for targeting these pathways in the context of human disease.
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Affiliation(s)
- Erich A. Nigg
- Biozentrum, University of Basel, Klingelbergstrasse 50/70, CH-4056 Basel, Switzerland
| | - Andrew J. Holland
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
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34
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McLamarrah TA, Buster DW, Galletta BJ, Boese CJ, Ryniawec JM, Hollingsworth NA, Byrnes AE, Brownlee CW, Slep KC, Rusan NM, Rogers GC. An ordered pattern of Ana2 phosphorylation by Plk4 is required for centriole assembly. J Cell Biol 2018; 217:1217-1231. [PMID: 29496738 PMCID: PMC5881488 DOI: 10.1083/jcb.201605106] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Revised: 06/19/2017] [Accepted: 01/19/2018] [Indexed: 12/15/2022] Open
Abstract
Polo-like kinase 4 (Plk4) initiates an early step in centriole assembly by phosphorylating Ana2/STIL, a structural component of the procentriole. Here, we show that Plk4 binding to the central coiled-coil (CC) of Ana2 is a conserved event involving Polo-box 3 and a previously unidentified putative CC located adjacent to the kinase domain. Ana2 is then phosphorylated along its length. Previous studies showed that Plk4 phosphorylates the C-terminal STil/ANa2 (STAN) domain of Ana2/STIL, triggering binding and recruitment of the cartwheel protein Sas6 to the procentriole assembly site. However, the physiological relevance of N-terminal phosphorylation was unknown. We found that Plk4 first phosphorylates the extreme N terminus of Ana2, which is critical for subsequent STAN domain modification. Phosphorylation of the central region then breaks the Plk4-Ana2 interaction. This phosphorylation pattern is important for centriole assembly and integrity because replacement of endogenous Ana2 with phospho-Ana2 mutants disrupts distinct steps in Ana2 function and inhibits centriole duplication.
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Affiliation(s)
- Tiffany A McLamarrah
- Department of Cellular and Molecular Medicine, University of Arizona Cancer Center, University of Arizona, Tucson, AZ
| | - Daniel W Buster
- Department of Cellular and Molecular Medicine, University of Arizona Cancer Center, University of Arizona, Tucson, AZ
| | - Brian J Galletta
- National Heart, Lung, and Blood Institute (NHLBI), National Institutes of Health, Bethesda, MD
| | - Cody J Boese
- Department of Cellular and Molecular Medicine, University of Arizona Cancer Center, University of Arizona, Tucson, AZ
| | - John M Ryniawec
- Department of Cellular and Molecular Medicine, University of Arizona Cancer Center, University of Arizona, Tucson, AZ
| | - Natalie Ann Hollingsworth
- Department of Cellular and Molecular Medicine, University of Arizona Cancer Center, University of Arizona, Tucson, AZ
| | - Amy E Byrnes
- Department of Biochemistry and Biophysics, Program in Molecular and Cellular Biophysics, University of North Carolina, Chapel Hill, NC
| | - Christopher W Brownlee
- Department of Cellular and Molecular Medicine, University of Arizona Cancer Center, University of Arizona, Tucson, AZ
| | - Kevin C Slep
- Department of Biology, University of North Carolina, Chapel Hill, NC
| | - Nasser M Rusan
- National Heart, Lung, and Blood Institute (NHLBI), National Institutes of Health, Bethesda, MD
| | - Gregory C Rogers
- Department of Cellular and Molecular Medicine, University of Arizona Cancer Center, University of Arizona, Tucson, AZ
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35
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Sieben C, Douglass KM, Guichard P, Manley S. Super-resolution microscopy to decipher multi-molecular assemblies. Curr Opin Struct Biol 2018; 49:169-176. [DOI: 10.1016/j.sbi.2018.03.017] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 03/16/2018] [Accepted: 03/17/2018] [Indexed: 12/12/2022]
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36
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Bianchi S, Rogala KB, Dynes NJ, Hilbert M, Leidel SA, Steinmetz MO, Gönczy P, Vakonakis I. Interaction between the Caenorhabditis elegans centriolar protein SAS-5 and microtubules facilitates organelle assembly. Mol Biol Cell 2018; 29:722-735. [PMID: 29367435 PMCID: PMC6003225 DOI: 10.1091/mbc.e17-06-0412] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 01/10/2018] [Accepted: 01/17/2018] [Indexed: 12/11/2022] Open
Abstract
Centrioles are microtubule-based organelles that organize the microtubule network and seed the formation of cilia and flagella. New centrioles assemble through a stepwise process dependent notably on the centriolar protein SAS-5 in Caenorhabditis elegans SAS-5 and its functional homologues in other species form oligomers that bind the centriolar proteins SAS-6 and SAS-4, thereby forming an evolutionarily conserved structural core at the onset of organelle assembly. Here, we report a novel interaction of SAS-5 with microtubules. Microtubule binding requires SAS-5 oligomerization and a disordered protein segment that overlaps with the SAS-4 binding site. Combined in vitro and in vivo analysis of select mutants reveals that the SAS-5-microtubule interaction facilitates centriole assembly in C. elegans embryos. Our findings lead us to propose that the interdependence of SAS-5 oligomerization and microtubule binding reflects an avidity mechanism, which also strengthens SAS-5 associations with other centriole components and, thus, promotes organelle assembly.
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Affiliation(s)
- Sarah Bianchi
- Laboratory of Biomolecular Research, Division of Biology and Chemistry, Paul Scherrer Institut, 5232 Villigen, Switzerland
| | - Kacper B Rogala
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, United Kingdom
| | - Nicola J Dynes
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology (École Polytechnique Fédérale de Lausanne), 1015 Lausanne, Switzerland
| | - Manuel Hilbert
- Laboratory of Biomolecular Research, Division of Biology and Chemistry, Paul Scherrer Institut, 5232 Villigen, Switzerland
| | - Sebastian A Leidel
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology (École Polytechnique Fédérale de Lausanne), 1015 Lausanne, Switzerland
| | - Michel O Steinmetz
- Laboratory of Biomolecular Research, Division of Biology and Chemistry, Paul Scherrer Institut, 5232 Villigen, Switzerland
- Biozentrum, University of Basel, 4056 Basel, Switzerland
| | - Pierre Gönczy
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology (École Polytechnique Fédérale de Lausanne), 1015 Lausanne, Switzerland
| | - Ioannis Vakonakis
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, United Kingdom
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37
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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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38
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Banterle N, Gönczy P. Centriole Biogenesis: From Identifying the Characters to Understanding the Plot. Annu Rev Cell Dev Biol 2017; 33:23-49. [PMID: 28813178 DOI: 10.1146/annurev-cellbio-100616-060454] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The centriole is a beautiful microtubule-based organelle that is critical for the proper execution of many fundamental cellular processes, including polarity, motility, and division. Centriole biogenesis, the making of this miniature architectural wonder, has emerged as an exemplary model to dissect the mechanisms governing the assembly of a eukaryotic organelle. Centriole biogenesis relies on a set of core proteins whose contributions to the assembly process have begun to be elucidated. Here, we review current knowledge regarding the mechanisms by which these core characters function in an orderly fashion to assemble the centriole. In particular, we discuss how having the correct proteins at the right place and at the right time is critical to first scaffold, then initiate, and finally execute the centriole assembly process, thus underscoring fundamental principles governing organelle biogenesis.
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Affiliation(s)
- Niccolò Banterle
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology (EPFL), CH-1015, Lausanne, Switzerland;
| | - Pierre Gönczy
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology (EPFL), CH-1015, Lausanne, Switzerland;
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39
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The PLK4-STIL-SAS-6 module at the core of centriole duplication. Biochem Soc Trans 2017; 44:1253-1263. [PMID: 27911707 PMCID: PMC5095913 DOI: 10.1042/bst20160116] [Citation(s) in RCA: 102] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Revised: 06/09/2016] [Accepted: 06/24/2016] [Indexed: 11/17/2022]
Abstract
Centrioles are microtubule-based core components of centrosomes and cilia. They are duplicated exactly once during S-phase progression. Central to formation of each new (daughter) centriole is the formation of a nine-fold symmetrical cartwheel structure onto which microtubule triplets are deposited. In recent years, a module comprising the protein kinase polo-like kinase 4 (PLK4) and the two proteins STIL and SAS-6 have been shown to stay at the core of centriole duplication. Depletion of any one of these three proteins blocks centriole duplication and, conversely, overexpression causes centriole amplification. In this short review article, we summarize recent insights into how PLK4, STIL and SAS-6 co-operate in space and time to form a new centriole. These advances begin to shed light on the very first steps of centriole biogenesis.
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40
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Abstract
Centrioles are microtubule-based cylinders essential for the formation of centrosomes and cilia. A recent study provides a new cell-free assay that reconstitutes the initial structure formed during centriole assembly - the cartwheel - and proposes a new model for its formation and growth.
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41
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Coupling Form and Function: How the Oligomerisation Symmetry of the SAS-6 Protein Contributes to the Architecture of Centriole Organelles. Symmetry (Basel) 2017. [DOI: 10.3390/sym9050074] [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] Open
Abstract
Centrioles make up the centrosome and basal bodies in animals and as such play important roles in cell division, signalling and motility. They possess characteristic 9-fold radial symmetry strongly influenced by the protein SAS-6. SAS-6 is essential for canonical centriole assembly as it forms the central core of the organelle, which is then surrounded by microtubules. SAS-6 self-assembles into an oligomer with elongated spokes that emanate towards the outer microtubule wall; in this manner, the symmetry of the SAS-6 oligomer influences centriole architecture and symmetry. Here, we summarise the form and symmetry of SAS-6 oligomers inferred from crystal structures and directly observed in vitro. We discuss how the strict 9-fold symmetry of centrioles may emerge, and how different forms of SAS-6 oligomers may be accommodated in the organelle architecture.
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42
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Cell-free reconstitution reveals centriole cartwheel assembly mechanisms. Nat Commun 2017; 8:14813. [PMID: 28332496 PMCID: PMC5376648 DOI: 10.1038/ncomms14813] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Accepted: 01/27/2017] [Indexed: 11/08/2022] Open
Abstract
How cellular organelles assemble is a fundamental question in biology. The centriole organelle organizes around a nine-fold symmetrical cartwheel structure typically ∼100 nm high comprising a stack of rings that each accommodates nine homodimers of SAS-6 proteins. Whether nine-fold symmetrical ring-like assemblies of SAS-6 proteins harbour more peripheral cartwheel elements is unclear. Furthermore, the mechanisms governing ring stacking are not known. Here we develop a cell-free reconstitution system for core cartwheel assembly. Using cryo-electron tomography, we uncover that the Chlamydomonas reinhardtii proteins CrSAS-6 and Bld10p together drive assembly of the core cartwheel. Moreover, we discover that CrSAS-6 possesses autonomous properties that ensure self-organized ring stacking. Mathematical fitting of reconstituted cartwheel height distribution suggests a mechanism whereby preferential addition of pairs of SAS-6 rings governs cartwheel growth. In conclusion, we have developed a cell-free reconstitution system that reveals fundamental assembly principles at the root of centriole biogenesis. The centriole is an organelle composed of rings of SAS-6 proteins that form a cartwheel structure. Here the authors develop a cell-free system to examine core cartwheel assembly of C. reinhardtii proteins and discover that CrSAS-6 has autonomous properties that facilitates self-organized stacking of pairs of rings.
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43
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Sugioka K, Hamill DR, Lowry JB, McNeely ME, Enrick M, Richter AC, Kiebler LE, Priess JR, Bowerman B. Centriolar SAS-7 acts upstream of SPD-2 to regulate centriole assembly and pericentriolar material formation. eLife 2017; 6. [PMID: 28092264 PMCID: PMC5342823 DOI: 10.7554/elife.20353] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Accepted: 01/15/2017] [Indexed: 12/30/2022] Open
Abstract
The centriole/basal body is a eukaryotic organelle that plays essential roles in cell division and signaling. Among five known core centriole proteins, SPD-2/Cep192 is the first recruited to the site of daughter centriole formation and regulates the centriolar localization of the other components in C. elegans and in humans. However, the molecular basis for SPD-2 centriolar localization remains unknown. Here, we describe a new centriole component, the coiled-coil protein SAS-7, as a regulator of centriole duplication, assembly and elongation. Intriguingly, our genetic data suggest that SAS-7 is required for daughter centrioles to become competent for duplication, and for mother centrioles to maintain this competence. We also show that SAS-7 binds SPD-2 and regulates SPD-2 centriolar recruitment, while SAS-7 centriolar localization is SPD-2-independent. Furthermore, pericentriolar material (PCM) formation is abnormal in sas-7 mutants, and the PCM-dependent induction of cell polarity that defines the anterior-posterior body axis frequently fails. We conclude that SAS-7 functions at the earliest step in centriole duplication yet identified and plays important roles in the orchestration of centriole and PCM assembly. DOI:http://dx.doi.org/10.7554/eLife.20353.001
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Affiliation(s)
- Kenji Sugioka
- Institute of Molecular Biology, University of Oregon, Eugene, United States
| | - Danielle R Hamill
- Department of Zoology, Ohio Wesleyan University, Delaware, United States
| | - Joshua B Lowry
- Institute of Molecular Biology, University of Oregon, Eugene, United States
| | - Marie E McNeely
- Department of Zoology, Ohio Wesleyan University, Delaware, United States
| | - Molly Enrick
- Department of Zoology, Ohio Wesleyan University, Delaware, United States
| | - Alyssa C Richter
- Department of Zoology, Ohio Wesleyan University, Delaware, United States
| | - Lauren E Kiebler
- Department of Zoology, Ohio Wesleyan University, Delaware, United States
| | - James R Priess
- Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, United States.,Molecular and Cellular Biology Program, University of Washington, Seattle, United States.,Department of Biology, University of Washington, Seattle, United States
| | - Bruce Bowerman
- Institute of Molecular Biology, University of Oregon, Eugene, United States
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44
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Abstract
The axoneme is the main extracellular part of cilia and flagella in eukaryotes. It consists of a microtubule cytoskeleton, which normally comprises nine doublets. In motile cilia, dynein ATPase motor proteins generate sliding motions between adjacent microtubules, which are integrated into a well-orchestrated beating or rotational motion. In primary cilia, there are a number of sensory proteins functioning on membranes surrounding the axoneme. In both cases, as the study of proteomics has elucidated, hundreds of proteins exist in this compartmentalized biomolecular system. In this article, we review the recent progress of structural studies of the axoneme and its components using electron microscopy and X-ray crystallography, mainly focusing on motile cilia. Structural biology presents snapshots (but not live imaging) of dynamic structural change and gives insights into the force generation mechanism of dynein, ciliary bending mechanism, ciliogenesis, and evolution of the axoneme.
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Affiliation(s)
- Takashi Ishikawa
- Laboratory of Biomolecular Research, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland.,Department of Biology, ETH Zurich, 5232 Villigen PSI, Switzerland
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45
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Abstract
Centrioles are evolutionarily conserved cylindrical cell organelles with characteristic radial symmetry. Despite their considerable size (400 nm × 200 nm, in humans), genetic studies suggest that relatively few protein components are involved in their assembly. We recently characterized the molecular architecture of the centrosomal P4.1-associated protein (CPAP), which is crucial for controlling the centriolar cylinder length. Here, we review the remarkable architecture of the C-terminal domain of CPAP, termed the G-box, which comprises a single, entirely solvent exposed, antiparallel β-sheet. Molecular dynamics simulations support the stability of the G-box domain even in the face of truncations or amino acid substitutions. The similarity of the G-box domain to amyloids (or amyloid precursors) is strengthened by its oligomeric arrangement to form continuous fibrils. G-box fibrils were observed in crystals as well as in solution and are also supported by simulations. We conclude that the G-box domain may well represent the best analogue currently available for studies of exposed β-sheets, unencumbered by additional structural elements or severe aggregations problems.
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Bauer M, Cubizolles F, Schmidt A, Nigg EA. Quantitative analysis of human centrosome architecture by targeted proteomics and fluorescence imaging. EMBO J 2016; 35:2152-2166. [PMID: 27539480 PMCID: PMC5048348 DOI: 10.15252/embj.201694462] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Accepted: 07/25/2016] [Indexed: 12/14/2022] Open
Abstract
Centrioles are essential for the formation of centrosomes and cilia. While numerical and/or structural centrosomes aberrations are implicated in cancer, mutations in centriolar and centrosomal proteins are genetically linked to ciliopathies, microcephaly, and dwarfism. The evolutionarily conserved mechanisms underlying centrosome biogenesis are centered on a set of key proteins, including Plk4, Sas-6, and STIL, whose exact levels are critical to ensure accurate reproduction of centrioles during cell cycle progression. However, neither the intracellular levels of centrosomal proteins nor their stoichiometry within centrosomes is presently known. Here, we have used two complementary approaches, targeted proteomics and EGFP-tagging of centrosomal proteins at endogenous loci, to measure protein abundance in cultured human cells and purified centrosomes. Our results provide a first assessment of the absolute and relative amounts of major components of the human centrosome. Specifically, they predict that human centriolar cartwheels comprise up to 16 stacked hubs and 1 molecule of STIL for every dimer of Sas-6. This type of quantitative information will help guide future studies of the molecular basis of centrosome assembly and function.
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Affiliation(s)
- Manuel Bauer
- Biozentrum, University of Basel, Basel, Switzerland
| | | | | | - Erich A Nigg
- Biozentrum, University of Basel, Basel, Switzerland
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Klein HCR, Guichard P, Hamel V, Gönczy P, Schwarz US. Computational support for a scaffolding mechanism of centriole assembly. Sci Rep 2016; 6:27075. [PMID: 27272020 PMCID: PMC4897622 DOI: 10.1038/srep27075] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 05/13/2016] [Indexed: 12/29/2022] Open
Abstract
Centrioles are essential for forming cilia, flagella and centrosomes. Successful centriole assembly requires proteins of the SAS-6 family, which can form oligomeric ring structures with ninefold symmetry in vitro. While important progress has been made in understanding SAS-6 protein biophysics, the mechanisms enabling ring formation in vivo remain elusive. Likewise, the mechanisms by which a nascent centriole forms near-orthogonal to an existing one are not known. Here, we investigate possible mechanisms of centriole assembly using coarse-grained Brownian dynamics computer simulations in combination with a rate equation approach. Our results suggest that without any external factors, strong stabilization associated with ring closure would be needed to enable efficient ring formation. Strikingly, our simulations reveal that a scaffold-assisted assembly mechanism can trigger robust ring formation owing to local cooperativity, and that this mechanism can also impart orthogonalilty to centriole assembly. Overall, our findings provide novel insights into the organizing principles governing the assembly of this important organelle.
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Affiliation(s)
- Heinrich C. R. Klein
- Institute for Theoretical Physics and BioQuant, Heidelberg University, D-69120 Heidelberg, Germany
| | - Paul Guichard
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Virginie Hamel
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Pierre Gönczy
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Ulrich S. Schwarz
- Institute for Theoretical Physics and BioQuant, Heidelberg University, D-69120 Heidelberg, Germany
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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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Hilbert M, Noga A, Frey D, Hamel V, Guichard P, Kraatz SHW, Pfreundschuh M, Hosner S, Flückiger I, Jaussi R, Wieser MM, Thieltges KM, Deupi X, Müller DJ, Kammerer RA, Gönczy P, Hirono M, Steinmetz MO. SAS-6 engineering reveals interdependence between cartwheel and microtubules in determining centriole architecture. Nat Cell Biol 2016; 18:393-403. [DOI: 10.1038/ncb3329] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Accepted: 02/10/2016] [Indexed: 01/09/2023]
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Abstract
Trichonympha is a symbiotic flagellate of many species of termites and of the wood-feeding cockroach. Remarkably, this unicellular organism harbors up to over ten thousand flagella on its surface, which serve to propel it through the viscous environment of the host hindgut. In the 1960s, analysis of resin-embedded Trichonympha samples by electron microscopy revealed that the basal bodies that give rise to these flagella are exceptionally long, with a proximal, cartwheel-bearing, region some 50 times longer than that of regular centrioles. In recent years, this salient feature has prompted the analysis of the 3D architecture of Trichonympha basal bodies in the native state using cryo-electron tomography. The resulting ~40 Å resolution map of the basal body proximal region revealed a number of novel features that may be conserved in centrioles of other systems. These include proximal-distal polarity of the pinhead structure that links the cartwheel to centriolar microtubules, as well as of the linker between the A and the C microtubules. Moreover, this work demonstrated that the cartwheel is made of stacked ring-like structures that likely each comprise 18 molecules of SAS-6 proteins.
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Affiliation(s)
- Paul Guichard
- Department of Cell Biology, University of Geneva, Geneva, Switzerland
| | - Pierre Gönczy
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland
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