1
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Ruehle MD, Li S, Agard DA, Pearson CG. Poc1 bridges basal body inner junctions to promote triplet microtubule integrity and connections. J Cell Biol 2024; 223:e202311104. [PMID: 38743010 PMCID: PMC11094743 DOI: 10.1083/jcb.202311104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 03/15/2024] [Accepted: 04/09/2024] [Indexed: 05/16/2024] Open
Abstract
Basal bodies (BBs) are conserved eukaryotic structures that organize cilia. They are comprised of nine, cylindrically arranged, triplet microtubules (TMTs) connected to each other by inter-TMT linkages which stabilize the structure. Poc1 is a conserved protein important for BB structural integrity in the face of ciliary forces transmitted to BBs. To understand how Poc1 confers BB stability, we identified the precise position of Poc1 in the Tetrahymena BB and the effect of Poc1 loss on BB structure. Poc1 binds at the TMT inner junctions, stabilizing TMTs directly. From this location, Poc1 also stabilizes inter-TMT linkages throughout the BB, including the cartwheel pinhead and the inner scaffold. The full localization of the inner scaffold protein Fam161A requires Poc1. As ciliary forces are increased, Fam161A is reduced, indicative of a force-dependent molecular remodeling of the inner scaffold. Thus, while not essential for BB assembly, Poc1 promotes BB interconnections that establish an architecture competent to resist ciliary forces.
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Affiliation(s)
- Marisa D. Ruehle
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Sam Li
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, CA, USA
| | - David A. Agard
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, CA, USA
- Chan Zuckerberg Institute for Advanced Biological Imaging, Redwood Shores, CA, USA
| | - Chad G. Pearson
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
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2
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Marshall WF. Chlamydomonas as a model system to study cilia and flagella using genetics, biochemistry, and microscopy. Front Cell Dev Biol 2024; 12:1412641. [PMID: 38872931 PMCID: PMC11169674 DOI: 10.3389/fcell.2024.1412641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2024] [Accepted: 05/13/2024] [Indexed: 06/15/2024] Open
Abstract
The unicellular green alga, Chlamydomonas reinhardtii, has played a central role in discovering much of what is currently known about the composition, assembly, and function of cilia and flagella. Chlamydomonas combines excellent genetics, such as the ability to grow cells as haploids or diploids and to perform tetrad analysis, with an unparalleled ability to detach and isolate flagella in a single step without cell lysis. The combination of genetics and biochemistry that is possible in Chlamydomonas has allowed many of the key components of the cilium to be identified by looking for proteins that are missing in a defined mutant. Few if any other model organisms allow such a seamless combination of genetic and biochemical approaches. Other major advantages of Chlamydomonas compared to other systems include the ability to induce flagella to regenerate in a highly synchronous manner, allowing the kinetics of flagellar growth to be measured, and the ability of Chlamydomonas flagella to adhere to glass coverslips allowing Intraflagellar Transport to be easily imaged inside the flagella of living cells, with quantitative precision and single-molecule resolution. These advantages continue to work in favor of Chlamydomonas as a model system going forward, and are now augmented by extensive genomic resources, a knockout strain collection, and efficient CRISPR gene editing. While Chlamydomonas has obvious limitations for studying ciliary functions related to animal development or organ physiology, when it comes to studying the fundamental biology of cilia and flagella, Chlamydomonas is simply unmatched in terms of speed, efficiency, cost, and the variety of approaches that can be brought to bear on a question.
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Affiliation(s)
- Wallace F. Marshall
- Department Biochemistry and Biophysics, University of California San Francisco, San Francisco, CA, United States
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3
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Laporte MH, Gambarotto D, Bertiaux É, Bournonville L, Louvel V, Nunes JM, Borgers S, Hamel V, Guichard P. Time-series reconstruction of the molecular architecture of human centriole assembly. Cell 2024; 187:2158-2174.e19. [PMID: 38604175 PMCID: PMC11060037 DOI: 10.1016/j.cell.2024.03.025] [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: 09/01/2023] [Revised: 12/21/2023] [Accepted: 03/19/2024] [Indexed: 04/13/2024]
Abstract
Centriole biogenesis, as in most organelle assemblies, involves the sequential recruitment of sub-structural elements that will support its function. To uncover this process, we correlated the spatial location of 24 centriolar proteins with structural features using expansion microscopy. A time-series reconstruction of protein distributions throughout human procentriole assembly unveiled the molecular architecture of the centriole biogenesis steps. We found that the process initiates with the formation of a naked cartwheel devoid of microtubules. Next, the bloom phase progresses with microtubule blade assembly, concomitantly with radial separation and rapid cartwheel growth. In the subsequent elongation phase, the tubulin backbone grows linearly with the recruitment of the A-C linker, followed by proteins of the inner scaffold (IS). By following six structural modules, we modeled 4D assembly of the human centriole. Collectively, this work provides a framework to investigate the spatial and temporal assembly of large macromolecules.
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Affiliation(s)
- Marine H Laporte
- University of Geneva, Department of Molecular and Cellular Biology, Faculty of Sciences, Geneva, Switzerland
| | - Davide Gambarotto
- University of Geneva, Department of Molecular and Cellular Biology, Faculty of Sciences, Geneva, Switzerland
| | - Éloïse Bertiaux
- University of Geneva, Department of Molecular and Cellular Biology, Faculty of Sciences, Geneva, Switzerland
| | - Lorène Bournonville
- University of Geneva, Department of Molecular and Cellular Biology, Faculty of Sciences, Geneva, Switzerland
| | - Vincent Louvel
- University of Geneva, Department of Molecular and Cellular Biology, Faculty of Sciences, Geneva, Switzerland
| | - José M Nunes
- University of Geneva, Department of Genetic and evolution, Faculty of Sciences, Geneva, Switzerland
| | - Susanne Borgers
- University of Geneva, Department of Molecular and Cellular Biology, Faculty of Sciences, Geneva, Switzerland
| | - Virginie Hamel
- University of Geneva, Department of Molecular and Cellular Biology, Faculty of Sciences, Geneva, Switzerland.
| | - Paul Guichard
- University of Geneva, Department of Molecular and Cellular Biology, Faculty of Sciences, Geneva, Switzerland.
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4
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Ruehle MD, Li S, Agard DA, Pearson CG. Poc1 is a basal body inner junction protein that promotes triplet microtubule integrity and interconnections. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.17.567593. [PMID: 38014135 PMCID: PMC10680851 DOI: 10.1101/2023.11.17.567593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
Basal bodies (BBs) are conserved eukaryotic structures that organize motile and primary cilia. The BB is comprised of nine, cylindrically arranged, triplet microtubules (TMTs) that are connected to each other by inter-TMT linkages which maintain BB structure. During ciliary beating, forces transmitted to the BB must be resisted to prevent BB disassembly. Poc1 is a conserved BB protein important for BBs to resist ciliary forces. To understand how Poc1 confers BB stability, we identified the precise position of Poc1 binding in the Tetrahymena BB and the effect of Poc1 loss on BB structure. Poc1 binds at the TMT inner junctions, stabilizing TMTs directly. From this location, Poc1 also stabilizes inter-TMT linkages throughout the BB, including the cartwheel pinhead and the inner scaffold. Moreover, we identify a molecular response to ciliary forces via a molecular remodeling of the inner scaffold, as determined by differences in Fam161A localization. Thus, while not essential for BB assembly, Poc1 promotes BB interconnections that establish an architecture competent to resist ciliary forces.
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Affiliation(s)
- Marisa D. Ruehle
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Sam Li
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, CA, USA
| | - David A. Agard
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, CA, USA
- Chan Zuckerberg Institute for Advanced Biological Imaging, 3400 Bridge Parkway, Redwood Shores, CA, USA
| | - Chad G. Pearson
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
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5
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Kalbfuss N, Gönczy P. Towards understanding centriole elimination. Open Biol 2023; 13:230222. [PMID: 37963546 PMCID: PMC10645514 DOI: 10.1098/rsob.230222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 09/14/2023] [Indexed: 11/16/2023] Open
Abstract
Centrioles are microtubule-based structures crucial for forming flagella, cilia and centrosomes. Through these roles, centrioles are critical notably for proper cell motility, signalling and division. Recent years have advanced significantly our understanding of the mechanisms governing centriole assembly and architecture. Although centrioles are typically very stable organelles, persisting over many cell cycles, they can also be eliminated in some cases. Here, we review instances of centriole elimination in a range of species and cell types. Moreover, we discuss potential mechanisms that enable the switch from a stable organelle to a vanishing one. Further work is expected to provide novel insights into centriole elimination mechanisms in health and disease, thereby also enabling scientists to readily manipulate organelle fate.
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Affiliation(s)
- Nils Kalbfuss
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Pierre Gönczy
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), 1015 Lausanne, Switzerland
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6
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Arora S, Rana M, Sachdev A, D’Souza JS. Appearing and disappearing acts of cilia. J Biosci 2023. [DOI: 10.1007/s12038-023-00326-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2023]
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7
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Arora S, Rana M, Sachdev A, D'Souza JS. Appearing and disappearing acts of cilia. J Biosci 2023; 48:8. [PMID: 36924208 PMCID: PMC10005925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2023]
Abstract
The past few decades have seen a rise in research on vertebrate cilia and ciliopathy, with interesting collaborations between basic and clinical scientists. This work includes studies on ciliary architecture, composition, evolution, and organelle generation and its biological role. The human body has cells that harbour any of the following four types of cilia: 9+0 motile, 9+0 immotile, 9+2 motile, and 9+2 immotile. Depending on the type, cilia play an important role in cell/fluid movement, mating, sensory perception, and development. Defects in cilia are associated with a wide range of human diseases afflicting the brain, heart, kidneys, respiratory tract, and reproductive system. These are commonly known as ciliopathies and affect millions of people worldwide. Due to their complex genetic etiology, diagnosis and therapy have remained elusive. Although model organisms like Chlamydomonas reinhardtii have been a useful source for ciliary research, reports of a fascinating and rewarding translation of this research into mammalian systems, especially humans, are seen. The current review peeks into one of the complex features of this organelle, namely its birth, the common denominators across the formation of both 9+0 and 9+2 ciliary types, the molecules involved in ciliogenesis, and the steps that go towards regulating their assembly and disassembly.
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Affiliation(s)
- Shashank Arora
- School of Biological Sciences, UM-DAE Centre for Excellence in Basic Sciences, Kalina Campus, Santacruz (E), Mumbai 400098, India
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8
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Koshimizu S, Minamino N, Nishiyama T, Yoro E, Sato M, Wakazaki M, Toyooka K, Ebine K, Sakakibara K, Ueda T, Yano K. Phylogenetic distribution and expression pattern analyses identified a divergent basal body assembly protein involved in land plant spermatogenesis. THE NEW PHYTOLOGIST 2022; 236:1182-1196. [PMID: 35842793 DOI: 10.1111/nph.18385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Accepted: 07/08/2022] [Indexed: 06/15/2023]
Abstract
Land plant spermatozoids commonly possess characteristic structures such as the spline, which consists of a microtubule array, the multilayered structure (MLS) in which the uppermost layer is a continuum of the spline, and multiple flagella. However, the molecular mechanisms underpinning spermatogenesis remain to be elucidated. We successfully identified candidate genes involved in spermatogenesis, deeply divergent BLD10s, by computational analyses combining multiple methods and omics data. We then examined the functions of BLD10s in the liverwort Marchantia polymorpha and the moss Physcomitrium patens. MpBLD10 and PpBLD10 are required for normal basal body (BB) and flagella formation. Mpbld10 mutants exhibited defects in remodeling of the cytoplasm and nucleus during spermatozoid formation, and thus MpBLD10 should be involved in chromatin reorganization and elimination of the cytoplasm during spermiogenesis. We identified orthologs of MpBLD10 and PpBLD10 in diverse Streptophyta and found that MpBLD10 and PpBLD10 are orthologous to BLD10/CEP135 family proteins, which function in BB assembly. However, BLD10s evolved especially quickly in land plants and MpBLD10 might have acquired additional functions in spermatozoid formation through rapid molecular evolution.
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Affiliation(s)
| | - Naoki Minamino
- Division of Cellular Dynamics, National Institute for Basic Biology, Okazaki, 444-8585, Japan
| | - Tomoaki Nishiyama
- Research Center for Experimental Modeling of Human Disease, Kanazawa University, Kanazawa, 920-0934, Japan
| | - Emiko Yoro
- Department of Life Science, Rikkyo University, Tokyo, 171-8501, Japan
| | - Mayuko Sato
- RIKEN Center for Sustainable Resource Science, Yokohama, 230-0045, Japan
| | - Mayumi Wakazaki
- RIKEN Center for Sustainable Resource Science, Yokohama, 230-0045, Japan
| | - Kiminori Toyooka
- RIKEN Center for Sustainable Resource Science, Yokohama, 230-0045, Japan
| | - Kazuo Ebine
- Division of Cellular Dynamics, National Institute for Basic Biology, Okazaki, 444-8585, Japan
- Department of Basic Biology, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, 444-8585, Japan
| | - Keiko Sakakibara
- Department of Life Science, Rikkyo University, Tokyo, 171-8501, Japan
| | - Takashi Ueda
- Division of Cellular Dynamics, National Institute for Basic Biology, Okazaki, 444-8585, Japan
- Department of Basic Biology, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, 444-8585, Japan
| | - Kentaro Yano
- School of Agriculture, Meiji University, Kawasaki, 214-8571, Japan
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9
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Noga A, Horii M, Goto Y, Toyooka K, Ishikawa T, Hirono M. Bld10p/Cep135 determines the number of triplets in the centriole independently of the cartwheel. EMBO J 2022; 41:e104582. [PMID: 36093892 PMCID: PMC9574746 DOI: 10.15252/embj.2020104582] [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] [Received: 01/30/2020] [Revised: 08/06/2022] [Accepted: 08/22/2022] [Indexed: 09/14/2023] Open
Abstract
The conserved nine-fold structural symmetry of the centriole is thought to be generated by cooperation between two mechanisms, one dependent on and the other independent of the cartwheel, a sub-centriolar structure consisting of a hub and nine spokes. However, the molecular entity of the cartwheel-independent mechanism has not been elucidated. Here, using Chlamydomonas reinhardtii mutants, we show that Bld10p/Cep135, a conserved centriolar protein that connects cartwheel spokes and triplet microtubules, plays a central role in this mechanism. Using immunoelectron microscopy, we localized hemagglutinin epitopes attached to distinct regions of Bld10p along two lines that connect adjacent triplets. Consistently, conventional and cryo-electron microscopy identified crosslinking structures at the same positions. In centrioles formed in the absence of the cartwheel, truncated Bld10p was found to significantly reduce the inter-triplet distance and frequently form eight-microtubule centrioles. These results suggest that the newly identified crosslinks are comprised of part of Bld10p/Cep135. We propose that Bld10p determines the inter-triplet distance in the centriole and thereby regulates the number of triplets in a cartwheel-independent manner.
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Affiliation(s)
- Akira Noga
- Department of Frontier BioscienceHosei UniversityTokyoJapan
- Department of Biological SciencesUniversity of TokyoTokyoJapan
- Division of Biology and ChemistryPaul Scherrer InstituteVilligenSwitzerland
| | - Mao Horii
- Department of Biological SciencesUniversity of TokyoTokyoJapan
| | - Yumi Goto
- RIKEN Center for Sustainable Resource ScienceYokohamaJapan
| | | | - Takashi Ishikawa
- Division of Biology and ChemistryPaul Scherrer InstituteVilligenSwitzerland
- Department of BiologyETH ZurichZurichSwitzerland
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10
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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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11
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Ramanantsalama MR, Landrein N, Casas E, Salin B, Blancard C, Bonhivers M, Robinson DR, Dacheux D. TFK1, a basal body transition fibre protein that is essential for cytokinesis in Trypanosoma brucei. J Cell Sci 2022; 135:275643. [PMID: 35588197 DOI: 10.1242/jcs.259893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 05/12/2022] [Indexed: 11/20/2022] Open
Abstract
In Trypanosoma brucei, transition fibres (TF) form a nine-bladed pattern-like structure connecting the base of the flagellum to the flagellar pocket membrane. Despite the characterization of two TF proteins, CEP164C and TbRP2, little is known about the organization of these fibres. Here, we report the identification and characterization of the first kinetoplastid-specific TF protein named TFK1 (Tb927.6.1180). Bioinformatics and functional domain analysis identified three TFK1 distinct domains: an N-terminal domain of an unpredicted function, a coiled-coil domain involved in TFK1-TFK1 interaction and a C-terminal intrinsically disordered region potentially involved in protein interaction. Cellular immuno-localization showed that TFK1 is a newly identified basal body maturation marker. Further, using ultrastructure expansion and immuno-electron microscopies we localized CEP164C and TbRP2 at the TF and TFK1 on the distal appendage matrix of the TF. Importantly, RNAi knockdown of TFK1 in bloodstream form cells induced misplacement of basal bodies, a defect in the furrow or fold generation and eventually cell death. We hypothesize that TFK1 is a basal body positioning specific actor and a key regulator of cytokinesis in the bloodstream form Trypanosoma brucei.
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Affiliation(s)
| | - Nicolas Landrein
- University of Bordeaux, CNRS, Microbiologie Fondamentale et Pathogénicité, UMR 5234, F-33000 Bordeaux, France
| | - Elina Casas
- University of Bordeaux, CNRS, Microbiologie Fondamentale et Pathogénicité, UMR 5234, F-33000 Bordeaux, France
| | - Bénédicte Salin
- University of Bordeaux, CNRS, Microscopy Department IBGC, UMR 5095, F-33000 Bordeaux, France
| | - Corinne Blancard
- University of Bordeaux, CNRS, Microscopy Department IBGC, UMR 5095, F-33000 Bordeaux, France
| | - Mélanie Bonhivers
- University of Bordeaux, CNRS, Microbiologie Fondamentale et Pathogénicité, UMR 5234, F-33000 Bordeaux, France
| | - Derrick R Robinson
- University of Bordeaux, CNRS, Microbiologie Fondamentale et Pathogénicité, UMR 5234, F-33000 Bordeaux, France
| | - Denis Dacheux
- University of Bordeaux, CNRS, Microbiologie Fondamentale et Pathogénicité, UMR 5234, F-33000 Bordeaux, France.,Bordeaux INP, Microbiologie Fondamentale et Pathogénicité, UMR 5234, F-33000 Bordeaux, France
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12
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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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13
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Zaqout S, Kaindl AM. Autosomal Recessive Primary Microcephaly: Not Just a Small Brain. Front Cell Dev Biol 2022; 9:784700. [PMID: 35111754 PMCID: PMC8802810 DOI: 10.3389/fcell.2021.784700] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 12/01/2021] [Indexed: 02/06/2023] Open
Abstract
Microcephaly or reduced head circumference results from a multitude of abnormal developmental processes affecting brain growth and/or leading to brain atrophy. Autosomal recessive primary microcephaly (MCPH) is the prototype of isolated primary (congenital) microcephaly, affecting predominantly the cerebral cortex. For MCPH, an accelerating number of mutated genes emerge annually, and they are involved in crucial steps of neurogenesis. In this review article, we provide a deeper look into the microcephalic MCPH brain. We explore cytoarchitecture focusing on the cerebral cortex and discuss diverse processes occurring at the level of neural progenitors, early generated and mature neurons, and glial cells. We aim to thereby give an overview of current knowledge in MCPH phenotype and normal brain growth.
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Affiliation(s)
- Sami Zaqout
- Department of Basic Medical Sciences, College of Medicine, QU Health, Qatar University, Doha, Qatar
- Biomedical and Pharmaceutical Research Unit, QU Health, Qatar University, Doha, Qatar
| | - Angela M. Kaindl
- Institute of Cell and Neurobiology, Charité—Universitätsmedizin Berlin, Berlin, Germany
- Center for Chronically Sick Children (Sozialpädiatrisches Zentrum, SPZ), Charité—Universitätsmedizin Berlin, Berlin, Germany
- Department of Pediatric Neurology, Charité—Universitätsmedizin Berlin, Berlin, Germany
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14
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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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15
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Gomes Pereira S, Sousa AL, Nabais C, Paixão T, Holmes AJ, Schorb M, Goshima G, Tranfield EM, Becker JD, Bettencourt-Dias M. The 3D architecture and molecular foundations of de novo centriole assembly via bicentrioles. Curr Biol 2021; 31:4340-4353.e7. [PMID: 34433076 DOI: 10.1101/2020.12.21.423647] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 06/01/2021] [Accepted: 07/26/2021] [Indexed: 05/19/2023]
Abstract
Centrioles are structurally conserved organelles, composing both centrosomes and cilia. In animal cycling cells, centrioles often form through a highly characterized process termed canonical duplication. However, a large diversity of eukaryotes assemble centrioles de novo through uncharacterized pathways. This unexplored diversity is key to understanding centriole assembly mechanisms and how they evolved to assist specific cellular functions. Here, we show that, during spermatogenesis of the bryophyte Physcomitrium patens, centrioles are born as a co-axially oriented centriole pair united by a cartwheel. Interestingly, we observe that these centrioles are twisted in opposite orientations. Microtubules emanate from the bicentrioles, which localize to the spindle poles during cell division. After their separation, the two resulting sister centrioles mature asymmetrically, elongating specific microtubule triplets and a naked cartwheel. Subsequently, two motile cilia are assembled that appear to alternate between different motility patterns. We further show that centriolar components SAS6, Bld10, and POC1, which are conserved across eukaryotes, are expressed during spermatogenesis and required for this de novo biogenesis pathway. Our work supports a scenario where centriole biogenesis, while driven by conserved molecular modules, is more diverse than previously thought.
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Affiliation(s)
- Sónia Gomes Pereira
- Instituto Gulbenkian de Ciência (IGC), Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal.
| | - Ana Laura Sousa
- Instituto Gulbenkian de Ciência (IGC), Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - Catarina Nabais
- Instituto Gulbenkian de Ciência (IGC), Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - Tiago Paixão
- Instituto Gulbenkian de Ciência (IGC), Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - Alexander J Holmes
- Instituto Gulbenkian de Ciência (IGC), Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - Martin Schorb
- Electron Microscopy Core Facility, European Molecular Biology Laboratory, 69117 Heidelberg, Germany
| | - Gohta Goshima
- Sugashima Marine Biological Laboratory, Graduate School of Science, Nagoya University, Sugashima, 429-63, Toba 517-0004, Japan; Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan
| | - Erin M Tranfield
- Instituto Gulbenkian de Ciência (IGC), Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - Jörg D Becker
- Instituto Gulbenkian de Ciência (IGC), Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal; Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, 2780-157 Oeiras, Portugal.
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16
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Gomes Pereira S, Sousa AL, Nabais C, Paixão T, Holmes AJ, Schorb M, Goshima G, Tranfield EM, Becker JD, Bettencourt-Dias M. The 3D architecture and molecular foundations of de novo centriole assembly via bicentrioles. Curr Biol 2021; 31:4340-4353.e7. [PMID: 34433076 DOI: 10.1016/j.cub.2021.07.063] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 06/01/2021] [Accepted: 07/26/2021] [Indexed: 12/18/2022]
Abstract
Centrioles are structurally conserved organelles, composing both centrosomes and cilia. In animal cycling cells, centrioles often form through a highly characterized process termed canonical duplication. However, a large diversity of eukaryotes assemble centrioles de novo through uncharacterized pathways. This unexplored diversity is key to understanding centriole assembly mechanisms and how they evolved to assist specific cellular functions. Here, we show that, during spermatogenesis of the bryophyte Physcomitrium patens, centrioles are born as a co-axially oriented centriole pair united by a cartwheel. Interestingly, we observe that these centrioles are twisted in opposite orientations. Microtubules emanate from the bicentrioles, which localize to the spindle poles during cell division. After their separation, the two resulting sister centrioles mature asymmetrically, elongating specific microtubule triplets and a naked cartwheel. Subsequently, two motile cilia are assembled that appear to alternate between different motility patterns. We further show that centriolar components SAS6, Bld10, and POC1, which are conserved across eukaryotes, are expressed during spermatogenesis and required for this de novo biogenesis pathway. Our work supports a scenario where centriole biogenesis, while driven by conserved molecular modules, is more diverse than previously thought.
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Affiliation(s)
- Sónia Gomes Pereira
- Instituto Gulbenkian de Ciência (IGC), Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal.
| | - Ana Laura Sousa
- Instituto Gulbenkian de Ciência (IGC), Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - Catarina Nabais
- Instituto Gulbenkian de Ciência (IGC), Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - Tiago Paixão
- Instituto Gulbenkian de Ciência (IGC), Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - Alexander J Holmes
- Instituto Gulbenkian de Ciência (IGC), Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - Martin Schorb
- Electron Microscopy Core Facility, European Molecular Biology Laboratory, 69117 Heidelberg, Germany
| | - Gohta Goshima
- Sugashima Marine Biological Laboratory, Graduate School of Science, Nagoya University, Sugashima, 429-63, Toba 517-0004, Japan; Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan
| | - Erin M Tranfield
- Instituto Gulbenkian de Ciência (IGC), Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - Jörg D Becker
- Instituto Gulbenkian de Ciência (IGC), Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal; Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, 2780-157 Oeiras, Portugal.
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17
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Abstract
In the context of animal or plant development, we tend to think of cells as small, simple, building blocks, such that complex patterns or shapes can only be constructed from large numbers of cells, with cells in different parts of the organism taking on different fates. However, cells themselves are far from simple, and often take on complex shapes with a remarkable degree of intracellular patterning. How do these patterns arise? As in embryogenesis, the development of structure inside a cell can be broken down into a number of basic processes. For each part of the cell, morphogenetic processes create internal structures such as organelles, which might correspond to organs at the level of a whole organism. Given that mechanisms exist to generate parts, patterning processes are required to ensure that the parts are distributed in the correct arrangement relative to the rest of the cell. Such patterning processes make reference to global polarity axes, requiring mechanisms for axiation which, in turn, require processes to break symmetry. These fundamental processes of symmetry breaking, axiation, patterning, and morphogenesis have been extensively studied in developmental biology but less so at the subcellular level. This review will focus on developmental processes that give eukaryotic cells their complex structures, with a focus on cytoskeletal organization in free-living cells, ciliates in particular, in which these processes are most readily apparent.
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18
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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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19
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Roopasree OJ, Adivitiya, Chakraborty S, Kateriya S, Veleri S. Centriole is the pivot coordinating dynamic signaling for cell proliferation and organization during early development in the vertebrates. Cell Biol Int 2021; 45:2178-2197. [PMID: 34288241 DOI: 10.1002/cbin.11667] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 07/12/2021] [Indexed: 11/07/2022]
Abstract
Vertebrates have an elaborate and functionally segmented body. It evolves from a single cell by systematic cell proliferation but attains a complex body structure with exquisite precision. This development requires two cellular events: cell cycle and ciliogenesis. For these events, the dynamic molecular signaling is converged at the centriole. The cell cycle helps in cell proliferation and growth of the body and is a highly regulated and integrated process. Its errors cause malignancies and developmental disorders. The cells newly proliferated are organized during organogenesis. For a cellular organization, dedicated signaling hubs are developed in the cells, and most often cilia are utilized. The cilium is generated from one of the centrioles involved in cell proliferation. The developmental signaling pathways hosted in cilia are essential for the elaboration of the body plan. The cilium's compartmental seclusion is ideal for noise-free molecular signaling and is essential for the precision of the body layout. The dysfunctional centrioles and primary cilia distort the development of body layout that manifest as serious developmental disorders. Thus, centriole has a dual role in the growth and cellular organization. It organizes dynamically expressed molecules of cell cycle and ciliogenesis and plays a balancing act to generate new cells and organize them during development. A putative master molecule may regulate and coordinate the dynamic gene expression at the centrioles. The convergence of many critical signaling components at the centriole reiterates the idea that centriole is a major molecular workstation involved in elaborating the structural design and complexity in vertebrates. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- O J Roopasree
- Agroprocessing Technology Division, CSIR-National Institute of Interdisciplinary Science and Technology, Thiruvananthapuram, Kerala 695019 and Academy of CSIR, Uttar Pradesh - 201002, India
| | - Adivitiya
- Laboratory of Optobiology, School of Biotechnology, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Soura Chakraborty
- Laboratory of Optobiology, School of Biotechnology, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Suneel Kateriya
- Laboratory of Optobiology, School of Biotechnology, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Shobi Veleri
- Drug Safety Division, ICMR-National Institute of Nutrition, Hyderabad, 500007, India
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20
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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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21
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Fatalska A, Stepinac E, Richter M, Kovacs L, Pietras Z, Puchinger M, Dong G, Dadlez M, Glover DM. The dimeric Golgi protein Gorab binds to Sas6 as a monomer to mediate centriole duplication. eLife 2021; 10:e57241. [PMID: 33704067 PMCID: PMC8009671 DOI: 10.7554/elife.57241] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 03/11/2021] [Indexed: 12/30/2022] Open
Abstract
The duplication and ninefold symmetry of the Drosophila centriole requires that the cartwheel molecule, Sas6, physically associates with Gorab, a trans-Golgi component. How Gorab achieves these disparate associations is unclear. Here, we use hydrogen-deuterium exchange mass spectrometry to define Gorab's interacting surfaces that mediate its subcellular localization. We identify a core stabilization sequence within Gorab's C-terminal coiled-coil domain that enables homodimerization, binding to Rab6, and thereby trans-Golgi localization. By contrast, part of the Gorab monomer's coiled-coil domain undergoes an antiparallel interaction with a segment of the parallel coiled-coil dimer of Sas6. This stable heterotrimeric complex can be visualized by electron microscopy. Mutation of a single leucine residue in Sas6's Gorab-binding domain generates a Sas6 variant with a sixteenfold reduced binding affinity for Gorab that cannot support centriole duplication. Thus, Gorab dimers at the Golgi exist in equilibrium with Sas6-associated monomers at the centriole to balance Gorab's dual role.
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Affiliation(s)
- Agnieszka Fatalska
- Department of Genetics, University of CambridgeCambridgeUnited Kingdom
- Division of Biology and Biological Engineering, California Institute of TechnologyPasadenaUnited States
- Institute of Biochemistry and Biophysics, Polish Academy of SciencesWarsawPoland
| | - Emma Stepinac
- Department of Medical Biochemistry, Max Perutz Labs, Medical University of ViennaViennaAustria
| | - Magdalena Richter
- Department of Genetics, University of CambridgeCambridgeUnited Kingdom
| | - Levente Kovacs
- Department of Genetics, University of CambridgeCambridgeUnited Kingdom
- Division of Biology and Biological Engineering, California Institute of TechnologyPasadenaUnited States
| | - Zbigniew Pietras
- Institute of Biochemistry and Biophysics, Polish Academy of SciencesWarsawPoland
| | - Martin Puchinger
- Department of Structural and Computational Biology, Max Perutz Labs, University of ViennaViennaAustria
| | - Gang Dong
- Department of Medical Biochemistry, Max Perutz Labs, Medical University of ViennaViennaAustria
| | - Michal Dadlez
- Institute of Biochemistry and Biophysics, Polish Academy of SciencesWarsawPoland
| | - David M Glover
- Department of Genetics, University of CambridgeCambridgeUnited Kingdom
- Division of Biology and Biological Engineering, California Institute of TechnologyPasadenaUnited States
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22
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Jaiswal S, Kasera H, Jain S, Khandelwal S, Singh P. Centrosome: A Microtubule Nucleating Cellular Machinery. J Indian Inst Sci 2021. [DOI: 10.1007/s41745-020-00213-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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23
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Avidor-Reiss T, Carr A, Fishman EL. The sperm centrioles. Mol Cell Endocrinol 2020; 518:110987. [PMID: 32810575 PMCID: PMC7606549 DOI: 10.1016/j.mce.2020.110987] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Revised: 08/07/2020] [Accepted: 08/10/2020] [Indexed: 12/13/2022]
Abstract
Centrioles are eukaryotic subcellular structures that produce and regulate massive cytoskeleton superstructures. They form centrosomes and cilia, regulate new centriole formation, anchor cilia to the cell, and regulate cilia function. These basic centriolar functions are executed in sperm cells during their amplification from spermatogonial stem cells during their differentiation to spermatozoa, and finally, after fertilization, when the sperm fuses with the egg. However, sperm centrioles exhibit many unique characteristics not commonly observed in other cell types, including structural remodeling, centriole-flagellum transition zone migration, and cell membrane association during meiosis. Here, we discuss five roles of sperm centrioles: orchestrating early spermatogenic cell divisions, forming the spermatozoon flagella, linking the spermatozoon head and tail, controlling sperm tail beating, and organizing the cytoskeleton of the zygote post-fertilization. We present the historic discovery of the centriole as a sperm factor that initiates embryogenesis, and recent genetic studies in humans and other mammals evaluating the current evidence for the five functions of sperm centrioles. We also examine information connecting the various sperm centriole functions to distinct clinical phenotypes. The emerging picture is that centrioles are essential sperm components with remarkable functional diversity and specialization that will require extensive and in-depth future studies.
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Affiliation(s)
- Tomer Avidor-Reiss
- Department of Biological Sciences, College of Natural Sciences and Mathematics, University of Toledo, Toledo, OH, USA; Department of Urology, College of Medicine and Life Sciences, University of Toledo, Toledo, OH, USA.
| | - Alexa Carr
- Department of Biological Sciences, College of Natural Sciences and Mathematics, University of Toledo, Toledo, OH, USA
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24
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Fatalska A, Dzhindzhev NS, Dadlez M, Glover DM. Interaction interface in the C-terminal parts of centriole proteins Sas6 and Ana2. Open Biol 2020; 10:200221. [PMID: 33171067 PMCID: PMC7729032 DOI: 10.1098/rsob.200221] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 10/20/2020] [Indexed: 12/14/2022] Open
Abstract
The centriole is a ninefold symmetrical structure found at the core of centrosomes and, as a basal body, at the base of cilia, whose conserved duplication is regulated by Plk4 kinase. Plk4 phosphorylates a single serine residue at the N-terminus of Ana2 to promote Ana2's loading to the site of procentriole formation. Four conserved serines in Ana2's STAN motif are then phosphorylated by Plk4, enabling Sas6 recruitment. Crystallographic data indicate that the coiled-coil domain of Ana2 forms a tetramer but the structure of full-length Ana2 has not been solved. Here, we have employed hydrogen-deuterium exchange coupled with mass spectrometry (HDX-MS) to uncover the conformational dynamics of Ana2, revealing the high flexibility of this protein with one rigid region. To determine the elusive nature of the interaction surfaces between Ana2 and Sas6, we have confirmed complex formation between the phosphomimetic form of Ana2 (Ana2-4D) and Sas6 in vitro and in vivo. Analysis of this complex by HDX-MS identifies short critical regions required for this interaction, which lie in the C-terminal parts of both proteins. Mutational studies confirmed the relevance of these regions for the Ana2-Sas6 interaction. The Sas6 site required for Ana2 binding is distinct from the site required for Sas6 to bind Gorab and Sas6 is able to bind both these protein partners simultaneously.
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Affiliation(s)
- Agnieszka Fatalska
- Department of Genetics, University of Cambridge, Cambridge CB2 3EH, UK
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland
| | | | - Michal Dadlez
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland
| | - David M. Glover
- Department of Genetics, University of Cambridge, Cambridge CB2 3EH, UK
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
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25
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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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26
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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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27
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McLamarrah TA, Speed SK, Ryniawec JM, Buster DW, Fagerstrom CJ, Galletta BJ, Rusan NM, Rogers GC. A molecular mechanism for the procentriole recruitment of Ana2. J Cell Biol 2020; 219:132764. [PMID: 31841145 PMCID: PMC7041687 DOI: 10.1083/jcb.201905172] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 10/24/2019] [Accepted: 11/12/2019] [Indexed: 12/15/2022] Open
Abstract
McLamarrah et al. characterize an early step in centriole duplication. They show that Plk4 hyperphosphorylates Ana2, which increases the affinity of Ana2 for the G-box domain of Sas4, promoting Ana2’s accumulation at the procentriole and, consequently, daughter centriole formation. During centriole duplication, a preprocentriole forms at a single site on the mother centriole through a process that includes the hierarchical recruitment of a conserved set of proteins, including the Polo-like kinase 4 (Plk4), Ana2/STIL, and the cartwheel protein Sas6. Ana2/STIL is critical for procentriole assembly, and its recruitment is controlled by the kinase activity of Plk4, but how this works remains poorly understood. A structural motif called the G-box in the centriole outer wall protein Sas4 interacts with a short region in the N terminus of Ana2/STIL. Here, we show that binding of Ana2 to the Sas4 G-box enables hyperphosphorylation of the Ana2 N terminus by Plk4. Hyperphosphorylation increases the affinity of the Ana2–G-box interaction, and, consequently, promotes the accumulation of Ana2 at the procentriole to induce daughter centriole formation.
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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
| | - Sarah K Speed
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD
| | - John M Ryniawec
- 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
| | - Carey J Fagerstrom
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD
| | - Brian J Galletta
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD
| | - Nasser M Rusan
- National Heart, Lung, and Blood Institute, 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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28
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Abstract
Drosophila spermatocyte centrioles are ideal for imaging studies. Their large, characteristic V conformation is both easy to identify and measure using standard imaging techniques. However, certain detailed features, such as their ninefold symmetry, are only visible below the diffraction limit of light. This is therefore a system that can benefit from the increased effective resolution potentially achievable by expansion microscopy. Here, I provide detailed protocols of two types of expansion microscopy methodologies applied to Drosophila spermatocyte centrioles, and discuss which is able to achieve the highest effective resolution in this system. I describe how to precisely measure these organelles post-expansion, and discuss how they can therefore be used as "molecular rulers" to troubleshoot and compare expansion techniques. I also provide protocols to combine expansion microscopy with super-resolution imaging in this tissue, discussing potential pitfalls. I conclude that expansion microscopy provides an effective alternative for thick tissues that are not amenable for traditional super-resolution techniques.
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Affiliation(s)
- Alan Wainman
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom.
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29
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Sullenberger C, Vasquez-Limeta A, Kong D, Loncarek J. With Age Comes Maturity: Biochemical and Structural Transformation of a Human Centriole in the Making. Cells 2020; 9:cells9061429. [PMID: 32526902 PMCID: PMC7349492 DOI: 10.3390/cells9061429] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 05/29/2020] [Accepted: 06/04/2020] [Indexed: 12/14/2022] Open
Abstract
Centrioles are microtubule-based cellular structures present in most human cells that build centrosomes and cilia. Proliferating cells have only two centrosomes and this number is stringently maintained through the temporally and spatially controlled processes of centriole assembly and segregation. The assembly of new centrioles begins in early S phase and ends in the third G1 phase from their initiation. This lengthy process of centriole assembly from their initiation to their maturation is characterized by numerous structural and still poorly understood biochemical changes, which occur in synchrony with the progression of cells through three consecutive cell cycles. As a result, proliferating cells contain three structurally, biochemically, and functionally distinct types of centrioles: procentrioles, daughter centrioles, and mother centrioles. This age difference is critical for proper centrosome and cilia function. Here we discuss the centriole assembly process as it occurs in somatic cycling human cells with a focus on the structural, biochemical, and functional characteristics of centrioles of different ages.
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30
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Pham KTM, Li Z. Regulated protein stabilization underpins the functional interplay among basal body components in Trypanosoma brucei. J Biol Chem 2020; 295:729-742. [PMID: 31819011 DOI: 10.1074/jbc.ra119.011352] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 12/03/2019] [Indexed: 11/06/2022] Open
Abstract
The basal body in the human parasite Trypanosoma brucei is structurally equivalent to the centriole in animals and functions in the nucleation of axonemal microtubules in the flagellum. T. brucei lacks many evolutionarily conserved centriolar protein homologs and constructs the basal body through unknown mechanisms. Two evolutionarily conserved centriole/basal body cartwheel proteins, TbSAS-6 and TbBLD10, and a trypanosome-specific protein, BBP65, play essential roles in basal body biogenesis in T. brucei, but how they cooperate in the regulation of basal body assembly remains elusive. Here using RNAi, endogenous epitope tagging, immunofluorescence microscopy, and 3D-structured illumination super-resolution microscopy, we identified a new trypanosome-specific protein named BBP164 and found that it has an essential role in basal body biogenesis in T. brucei Further investigation of the functional interplay among BBP164 and the other three regulators of basal body assembly revealed that BBP164 and BBP65 are interdependent for maintaining their stability and depend on TbSAS-6 and TbBLD10 for their stabilization in the basal body. Additionally, TbSAS-6 and TbBLD10 are independent from each other and from BBP164 and BBP65 for maintaining their stability in the basal body. These findings demonstrate that basal body cartwheel proteins are required for stabilizing other basal body components and uncover that regulation of protein stability is an unusual control mechanism for assembly of the basal body in T. brucei.
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Affiliation(s)
- Kieu T M Pham
- Department of Microbiology and Molecular Genetics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas 77030
| | - Ziyin Li
- Department of Microbiology and Molecular Genetics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas 77030
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31
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Touré A, Martinez G, Kherraf ZE, Cazin C, Beurois J, Arnoult C, Ray PF, Coutton C. The genetic architecture of morphological abnormalities of the sperm tail. Hum Genet 2020; 140:21-42. [PMID: 31950240 DOI: 10.1007/s00439-020-02113-x] [Citation(s) in RCA: 104] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 01/06/2020] [Indexed: 12/29/2022]
Abstract
Spermatozoa contain highly specialized structural features reflecting unique functions required for fertilization. Among them, the flagellum is a sperm-specific organelle required to generate the motility, which is essential to reach the egg. The flagellum integrity is, therefore, critical for normal sperm function and flagellum defects consistently lead to male infertility due to reduced or absent sperm motility defined as asthenozoospermia. Multiple morphological abnormalities of the flagella (MMAF), also called short tails, is among the most severe forms of sperm flagellum defects responsible for male infertility and is characterized by the presence in the ejaculate of spermatozoa being short, coiled, absent and of irregular caliber. Recent studies have demonstrated that MMAF is genetically heterogeneous which is consistent with the large number of proteins (over one thousand) localized in the human sperm flagella. In the past 5 years, genomic investigation of the MMAF phenotype allowed the identification of 18 genes whose mutations induce MMAF and infertility. Here we will review information about those genes including their expression pattern, the features of the encoded proteins together with their localization within the different flagellar protein complexes (axonemal or peri-axonemal) and their potential functions. We will categorize the identified MMAF genes following the protein complexes, functions or biological processes they may be associated with, based on the current knowledge in the field.
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Affiliation(s)
- Aminata Touré
- Faculté de Médecine, Université Paris Descartes, Sorbonne Paris Cité, 75014, Paris, France.,INSERM U1016, Institut Cochin, 75014, Paris, France.,Centre National de La Recherche Scientifique UMR8104, 75014, Paris, France
| | - Guillaume Martinez
- INSERM U1209, CNRS UMR 5309, Institute for Advanced Biosciences, Team Genetics Epigenetics and Therapies of Infertility, Univ. Grenoble Alpes, 38000, Grenoble, France.,CHU Grenoble Alpes, UM de Génétique Chromosomique, 38000, Grenoble, France
| | - Zine-Eddine Kherraf
- INSERM U1209, CNRS UMR 5309, Institute for Advanced Biosciences, Team Genetics Epigenetics and Therapies of Infertility, Univ. Grenoble Alpes, 38000, Grenoble, France.,CHU Grenoble Alpes, UM GI-DPI, 38000, Grenoble, France
| | - Caroline Cazin
- INSERM U1209, CNRS UMR 5309, Institute for Advanced Biosciences, Team Genetics Epigenetics and Therapies of Infertility, Univ. Grenoble Alpes, 38000, Grenoble, France
| | - Julie Beurois
- INSERM U1209, CNRS UMR 5309, Institute for Advanced Biosciences, Team Genetics Epigenetics and Therapies of Infertility, Univ. Grenoble Alpes, 38000, Grenoble, France
| | - Christophe Arnoult
- INSERM U1209, CNRS UMR 5309, Institute for Advanced Biosciences, Team Genetics Epigenetics and Therapies of Infertility, Univ. Grenoble Alpes, 38000, Grenoble, France
| | - Pierre F Ray
- INSERM U1209, CNRS UMR 5309, Institute for Advanced Biosciences, Team Genetics Epigenetics and Therapies of Infertility, Univ. Grenoble Alpes, 38000, Grenoble, France.,CHU Grenoble Alpes, UM GI-DPI, 38000, Grenoble, France
| | - Charles Coutton
- INSERM U1209, CNRS UMR 5309, Institute for Advanced Biosciences, Team Genetics Epigenetics and Therapies of Infertility, Univ. Grenoble Alpes, 38000, Grenoble, France. .,CHU Grenoble Alpes, UM de Génétique Chromosomique, 38000, Grenoble, France.
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32
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Regulated protein stabilization underpins the functional interplay among basal body components in Trypanosoma brucei. J Biol Chem 2020. [DOI: 10.1016/s0021-9258(17)49931-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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33
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Bayless BA, Navarro FM, Winey M. Motile Cilia: Innovation and Insight From Ciliate Model Organisms. Front Cell Dev Biol 2019; 7:265. [PMID: 31737631 PMCID: PMC6838636 DOI: 10.3389/fcell.2019.00265] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Accepted: 10/18/2019] [Indexed: 12/15/2022] Open
Abstract
Ciliates are a powerful model organism for the study of basal bodies and motile cilia. These single-celled protists contain hundreds of cilia organized in an array making them an ideal system for both light and electron microscopy studies. Isolation and subsequent proteomic analysis of both cilia and basal bodies have been carried out to great success in ciliates. These studies reveal that ciliates share remarkable protein conservation with metazoans and have identified a number of essential basal body/ciliary proteins. Ciliates also boast a genetic and molecular toolbox that allows for facile manipulation of ciliary genes. Reverse genetics studies in ciliates have expanded our understanding of how cilia are positioned within an array, assembled, stabilized, and function at a molecular level. The advantages of cilia number coupled with a robust genetic and molecular toolbox have established ciliates as an ideal system for motile cilia and basal body research and prove a promising system for future research.
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Affiliation(s)
- Brian A Bayless
- Department of Biology, Santa Clara University, Santa Clara, CA, United States
| | - Francesca M Navarro
- Department of Biology, Santa Clara University, Santa Clara, CA, United States
| | - Mark Winey
- Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA, United States
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34
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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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35
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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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36
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Klena N, Gambarotto D, Le Guennec M, Borgers S, Guichard P, Hamel V. Isolation and Fluorescence Imaging for Single-particle Reconstruction of Chlamydomonas Centrioles. J Vis Exp 2018. [PMID: 30295659 PMCID: PMC6235292 DOI: 10.3791/58109] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Centrioles are large macromolecular assemblies important for the proper execution of fundamental cell biological processes such as cell division, cell motility, or cell signaling. The green algae Chlamydomonas reinhardtii has proven to be an insightful model in the study of centriole architecture, function, and protein composition. Despite great advances toward understanding centriolar architecture, one of the current challenges is to determine the precise localization of centriolar components within structural regions of the centriole in order to better understand their role in centriole biogenesis. A major limitation lies in the resolution of fluorescence microscopy, which complicates the interpretation of protein localization in this organelle with dimensions close to the diffraction limit. To tackle this question, we are providing a method to purify and image a large number of C. reinhardtii centrioles with different orientations using super-resolution microscopy. This technique allows further processing of data through fluorescent single-particle averaging (Fluo-SPA) owing to the large number of centrioles acquired. Fluo-SPA generates averages of stained C. reinhardtii centrioles in different orientations, thus facilitating the localization of distinct proteins in centriolar sub-regions. Importantly, this method can be applied to image centrioles from other species or other large macromolecular assemblies.
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Affiliation(s)
- Nikolai Klena
- Department of Cell Biology, Sciences III, University of Geneva
| | | | | | - Susanne Borgers
- Department of Cell Biology, Sciences III, University of Geneva
| | - Paul Guichard
- Department of Cell Biology, Sciences III, University of Geneva;
| | - Virginie Hamel
- Department of Cell Biology, Sciences III, University of Geneva;
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37
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Chlamydomonas Basal Bodies as Flagella Organizing Centers. Cells 2018; 7:cells7070079. [PMID: 30018231 PMCID: PMC6070942 DOI: 10.3390/cells7070079] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 07/09/2018] [Accepted: 07/10/2018] [Indexed: 11/17/2022] Open
Abstract
During ciliogenesis, centrioles convert to membrane-docked basal bodies, which initiate the formation of cilia/flagella and template the nine doublet microtubules of the flagellar axoneme. The discovery that many human diseases and developmental disorders result from defects in flagella has fueled a strong interest in the analysis of flagellar assembly. Here, we will review the structure, function, and development of basal bodies in the unicellular green alga Chlamydomonas reinhardtii, a widely used model for the analysis of basal bodies and flagella. Intraflagellar transport (IFT), a flagella-specific protein shuttle critical for ciliogenesis, was first described in C. reinhardtii. A focus of this review will be on the role of the basal bodies in organizing the IFT machinery.
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38
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Kovacs L, Chao-Chu J, Schneider S, Gottardo M, Tzolovsky G, Dzhindzhev NS, Riparbelli MG, Callaini G, Glover DM. Gorab is a Golgi protein required for structure and duplication of Drosophila centrioles. Nat Genet 2018; 50:1021-1031. [PMID: 29892014 PMCID: PMC6097609 DOI: 10.1038/s41588-018-0149-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 04/17/2018] [Indexed: 11/09/2022]
Abstract
We demonstrate that a Drosophila Golgi protein, Gorab, is present not only in the trans-Golgi but also in the centriole cartwheel where, complexed to Sas6, it is required for centriole duplication. In addition to centriole defects, flies lacking Gorab are uncoordinated due to defects in sensory cilia, which lose their nine-fold symmetry. We demonstrate the separation of centriole and Golgi functions of Drosophila Gorab in two ways: first, we have created Gorab variants that are unable to localize to trans-Golgi but can still rescue the centriole and cilia defects of gorab null flies; second, we show that expression of C-terminally tagged Gorab disrupts Golgi functions in cytokinesis of male meiosis, a dominant phenotype overcome by mutations preventing Golgi targeting. Our findings suggest that during animal evolution, a Golgi protein has arisen with a second, apparently independent, role in centriole duplication.
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Affiliation(s)
| | - Jennifer Chao-Chu
- University of Cambridge, Cambridge, UK
- The University of Hong Kong, Hong Kong, China
| | | | - Marco Gottardo
- University of Siena, Siena, Italy
- Alexander von Humboldt Foundation Fellow, Center for Molecular Medicine and Institute for Biochemistry of the University of Cologne, Cologne, Germany
| | - George Tzolovsky
- University of Cambridge, Cambridge, UK
- Carl Zeiss Microscopy Ltd, ZEISS Group, Cambridge, UK
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39
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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: 306] [Impact Index Per Article: 51.0] [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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40
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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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41
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Wang JT, Stearns T. The ABCs of Centriole Architecture: The Form and Function of Triplet Microtubules. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 2018; 82:145-155. [PMID: 29540555 PMCID: PMC11156431 DOI: 10.1101/sqb.2017.82.034496] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/09/2024]
Abstract
The centriole is a defining feature of many eukaryotic cells. It nucleates a cilium, organizes microtubules as part of the centrosome, and is duplicated in coordination with the cell cycle. Centrioles have a remarkable structure, consisting of microtubules arranged in a barrel with ninefold radial symmetry. At their base, or proximal end, centrioles have unique triplet microtubules, formed from three microtubules linked to each other. This microtubule organization is not found anywhere else in the cell, is conserved in all major branches of the eukaryotic tree, and likely was present in the last eukaryotic common ancestor. At their tip, or distal end, centrioles have doublet microtubules, which template the cilium. Here, we consider the structures of the compound microtubules in centrioles and discuss potential mechanisms for their formation and their function. We propose that triplet microtubules are required for the structural integrity of centrioles, allowing the centriole to serve as the essential nucleator of the cilium.
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Affiliation(s)
- Jennifer T Wang
- Department of Biology, Stanford University, Stanford, California 94305-5020
| | - Tim Stearns
- Department of Biology, Stanford University, Stanford, California 94305-5020
- Department of Genetics, Stanford School of Medicine, Stanford, California 94305
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42
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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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43
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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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44
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Identification of Chlamydomonas Central Core Centriolar Proteins Reveals a Role for Human WDR90 in Ciliogenesis. Curr Biol 2017; 27:2486-2498.e6. [PMID: 28781053 PMCID: PMC6399476 DOI: 10.1016/j.cub.2017.07.011] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Revised: 06/08/2017] [Accepted: 07/04/2017] [Indexed: 11/21/2022]
Abstract
Centrioles are evolutionarily conserved macromolecular structures that are fundamental to form cilia, flagella, and centrosomes. Centrioles are 9-fold symmetrical microtubule-based cylindrical barrels comprising three regions that can be clearly distinguished in the Chlamydomonas reinhardtii organelle: an ∼100-nm-long proximal region harboring a cartwheel; an ∼250-nm-long central core region containing a Y-shaped linker; and an ∼150-nm-long distal region ending at the transitional plate. Despite the discovery of many centriolar components, no protein has been localized specifically to the central core region in Chlamydomonas thus far. Here, combining relative quantitative mass spectrometry and super-resolution microscopy on purified Chlamydomonas centrioles, we identified POB15 and POC16 as two proteins of the central core region, the distribution of which correlates with that of tubulin glutamylation. We demonstrated that POB15 is an inner barrel protein within this region. Moreover, we developed an assay to uncover temporal relationships between centriolar proteins during organelle assembly and thus established that POB15 is recruited after the cartwheel protein CrSAS-6 and before tubulin glutamylation takes place. Furthermore, we discovered that two poc16 mutants exhibit flagellar defects, indicating that POC16 is important for flagellum biogenesis. In addition, we discovered that WDR90, the human homolog of POC16, localizes to a region of human centrioles that we propose is analogous to the central core of Chlamydomonas centrioles. Moreover, we demonstrate that WDR90 is required for ciliogenesis, echoing the findings in Chlamydomonas. Overall, our work provides novel insights into the identity and function of centriolar central core components. Mapping of centriolar sub-regions using structured illumination microscopy Relative quantitative mass spectrometry reveals novel centriolar components Identification of Chlamydomonas central core proteins POB15 and POC16 POC16 and its human homolog WDR90 promote flagella/cilia formation
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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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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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Lattao R, Kovács L, Glover DM. The Centrioles, Centrosomes, Basal Bodies, and Cilia of Drosophila melanogaster. Genetics 2017; 206:33-53. [PMID: 28476861 PMCID: PMC5419478 DOI: 10.1534/genetics.116.198168] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Accepted: 03/24/2017] [Indexed: 12/19/2022] Open
Abstract
Centrioles play a key role in the development of the fly. They are needed for the correct formation of centrosomes, the organelles at the poles of the spindle that can persist as microtubule organizing centers (MTOCs) into interphase. The ability to nucleate cytoplasmic microtubules (MTs) is a property of the surrounding pericentriolar material (PCM). The centriole has a dual life, existing not only as the core of the centrosome but also as the basal body, the structure that templates the formation of cilia and flagellae. Thus the structure and functions of the centriole, the centrosome, and the basal body have an impact upon many aspects of development and physiology that can readily be modeled in Drosophila Centrosomes are essential to give organization to the rapidly increasing numbers of nuclei in the syncytial embryo and for the spatially precise execution of cell division in numerous tissues, particularly during male meiosis. Although mitotic cell cycles can take place in the absence of centrosomes, this is an error-prone process that opens up the fly to developmental defects and the potential of tumor formation. Here, we review the structure and functions of the centriole, the centrosome, and the basal body in different tissues and cultured cells of Drosophila melanogaster, highlighting their contributions to different aspects of development and cell division.
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Affiliation(s)
- Ramona Lattao
- Department of Genetics, University of Cambridge, CB2 3EH, United Kingdom
| | - Levente Kovács
- Department of Genetics, University of Cambridge, CB2 3EH, United Kingdom
| | - David M Glover
- Department of Genetics, University of Cambridge, CB2 3EH, United Kingdom
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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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Proximity Interactions among Basal Body Components in Trypanosoma brucei Identify Novel Regulators of Basal Body Biogenesis and Inheritance. mBio 2017; 8:mBio.02120-16. [PMID: 28049148 PMCID: PMC5210500 DOI: 10.1128/mbio.02120-16] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The basal body shares similar architecture with centrioles in animals and is involved in nucleating flagellar axonemal microtubules in flagellated eukaryotes. The early-branching Trypanosoma brucei possesses a motile flagellum nucleated from the basal body that consists of a mature basal body and an adjacent pro-basal body. Little is known about the basal body proteome and its roles in basal body biogenesis and flagellar axoneme assembly in T. brucei. Here, we report the identification of 14 conserved centriole/basal body protein homologs and 25 trypanosome-specific basal body proteins. These proteins localize to distinct subdomains of the basal body, and several of them form a ring-like structure surrounding the basal body barrel. Functional characterization of representative basal body proteins revealed distinct roles in basal body duplication/separation and flagellar axoneme assembly. Overall, this work identified novel proteins required for basal body duplication and separation and uncovered new functions of conserved basal body proteins in basal body duplication and separation, highlighting an unusual mechanism of basal body biogenesis and inheritance in this early divergent eukaryote. The basal body in the early-branching protozoan Trypanosoma brucei nucleates flagellum assembly and also regulates organelle segregation, cell morphogenesis, and cell division. However, the molecular composition and the assembly process of the basal body remain poorly understood. Here, we identify 14 conserved basal body proteins and 25 trypanosome-specific basal body proteins via bioinformatics, localization-based screening, and proximity-dependent biotin identification. We further localized these proteins to distinct subdomains of the basal body by using fluorescence microscopy and superresolution microscopy, discovered novel regulators of basal body duplication and separation, and uncovered new functions of conserved basal body proteins in basal body duplication and separation. This work lays the foundation for dissecting the mechanisms underlying basal body biogenesis and inheritance in T. brucei.
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Abstract
Anton van Leeuwenhoek's startling microscopic observations in the 1600s first stimulated fascination with the way that cells use cilia to generate currents and to swim in a fluid environment. Research in recent decades has yielded deep knowledge about the mechanical and biochemical nature of these organelles but only opened a greater fascination about how such beautifully intricate and multifunctional structures arose during evolution. Answers to this evolutionary puzzle are not only sought to satisfy basic curiosity, but also, as stated so eloquently by Dobzhansky (Am Zool 4: 443 [1964]), because "nothing in biology makes sense except in the light of evolution." Here I attempt to summarize current knowledge of what ciliary organelles of the last eukaryotic common ancestor (LECA) were like, explore the ways in which cilia have evolved since that time, and speculate on the selective processes that might have generated these organelles during early eukaryotic evolution.
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Affiliation(s)
- David R Mitchell
- Department of Cell and Developmental Biology, SUNY Upstate Medical University, Syracuse, New York 13210
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