1
|
Camblor-Perujo S, Ozer Yildiz E, Küpper H, Overhoff M, Rastogi S, Bazzi H, Kononenko NL. The AP-2 complex interacts with γ-TuRC and regulates the proliferative capacity of neural progenitors. Life Sci Alliance 2024; 7:e202302029. [PMID: 38086550 PMCID: PMC10716017 DOI: 10.26508/lsa.202302029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 11/23/2023] [Accepted: 11/27/2023] [Indexed: 12/18/2023] Open
Abstract
Centrosomes are organelles that nucleate microtubules via the activity of gamma-tubulin ring complexes (γ-TuRC). In the developing brain, centrosome integrity is central to the progression of the neural progenitor cell cycle, and its loss leads to microcephaly. We show that NPCs maintain centrosome integrity via the endocytic adaptor protein complex-2 (AP-2). NPCs lacking AP-2 exhibit defects in centrosome formation and mitotic progression, accompanied by DNA damage and accumulation of p53. This function of AP-2 in regulating the proliferative capacity of NPCs is independent of its role in clathrin-mediated endocytosis and is coupled to its association with the GCP2, GCP3, and GCP4 components of γ-TuRC. We find that AP-2 maintains γ-TuRC organization and regulates centrosome function at the level of MT nucleation. Taken together, our data reveal a novel, noncanonical function of AP-2 in regulating the proliferative capacity of NPCs and open new avenues for the identification of novel therapeutic strategies for the treatment of neurodevelopmental and neurodegenerative disorders with AP-2 complex dysfunction.
Collapse
Affiliation(s)
| | - Ebru Ozer Yildiz
- CECAD Excellence Center, University of Cologne, Cologne, Germany
| | - Hanna Küpper
- CECAD Excellence Center, University of Cologne, Cologne, Germany
| | - Melina Overhoff
- CECAD Excellence Center, University of Cologne, Cologne, Germany
- Center for Physiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Saumya Rastogi
- CECAD Excellence Center, University of Cologne, Cologne, Germany
| | - Hisham Bazzi
- CECAD Excellence Center, University of Cologne, Cologne, Germany
- Center for Molecular Medicine Cologne, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
- Department of Dermatology and Venereology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Natalia L Kononenko
- CECAD Excellence Center, University of Cologne, Cologne, Germany
- Center for Physiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
- Center for Molecular Medicine Cologne, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
- Institute of Genetics, Natural Faculty, University of Cologne, Cologne, Germany
| |
Collapse
|
2
|
Carden S, Vitiello E, Rosa E Silva I, Holder J, Quarantotti V, Kishore K, Roamio Franklin VN, D'Santos C, Ochi T, van Breugel M, Gergely F. Proteomic profiling of centrosomes across multiple mammalian cell and tissue types by an affinity capture method. Dev Cell 2023; 58:2393-2410.e9. [PMID: 37852252 DOI: 10.1016/j.devcel.2023.09.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 07/27/2023] [Accepted: 09/25/2023] [Indexed: 10/20/2023]
Abstract
Centrosomes are the major microtubule-organizing centers in animals and play fundamental roles in many cellular processes. Understanding how their composition varies across diverse cell types and how it is altered in disease are major unresolved questions, yet currently available centrosome isolation protocols are cumbersome and time-consuming, and they lack scalability. Here, we report the development of centrosome affinity capture (CAPture)-mass spectrometry (MS), a powerful one-step purification method to obtain high-resolution centrosome proteomes from mammalian cells. Utilizing a synthetic peptide derived from CCDC61 protein, CAPture specifically isolates intact centrosomes. Importantly, as a bead-based affinity method, it enables rapid sample processing and multiplexing unlike conventional approaches. Our study demonstrates the power of CAPture-MS to elucidate cell-type-dependent heterogeneity in centrosome composition, dissect hierarchical interactions, and identify previously unknown centrosome components. Overall, CAPture-MS represents a transformative tool to unveil temporal, regulatory, cell-type- and tissue-specific changes in centrosome proteomes in health and disease.
Collapse
Affiliation(s)
- Sarah Carden
- CRUK Cambridge Institute, Li Ka Shing Centre, University of Cambridge, Cambridge, UK
| | - Elisa Vitiello
- Department of Biochemistry, University of Oxford, Oxford, UK
| | | | - James Holder
- Department of Biochemistry, University of Oxford, Oxford, UK
| | - Valentina Quarantotti
- CRUK Cambridge Institute, Li Ka Shing Centre, University of Cambridge, Cambridge, UK
| | - Kamal Kishore
- CRUK Cambridge Institute, Li Ka Shing Centre, University of Cambridge, Cambridge, UK
| | | | - Clive D'Santos
- CRUK Cambridge Institute, Li Ka Shing Centre, University of Cambridge, Cambridge, UK
| | - Takashi Ochi
- MRC Laboratory of Molecular Biology, Cambridge, UK; The Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, University of Leeds, Leeds, UK.
| | - Mark van Breugel
- MRC Laboratory of Molecular Biology, Cambridge, UK; School of Biological & Behavioural Sciences, Queen Mary University of London, London, UK.
| | - Fanni Gergely
- CRUK Cambridge Institute, Li Ka Shing Centre, University of Cambridge, Cambridge, UK; Department of Biochemistry, University of Oxford, Oxford, UK.
| |
Collapse
|
3
|
Henkin G, Brito C, Thomas C, Surrey T. The minus-end depolymerase KIF2A drives flux-like treadmilling of γTuRC-uncapped microtubules. J Cell Biol 2023; 222:e202304020. [PMID: 37615667 PMCID: PMC10450741 DOI: 10.1083/jcb.202304020] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 07/27/2023] [Accepted: 08/04/2023] [Indexed: 08/25/2023] Open
Abstract
During mitosis, microtubules in the spindle turn over continuously. At spindle poles, where microtubule minus ends are concentrated, microtubule nucleation and depolymerization, the latter required for poleward microtubule flux, happen side by side. How these seemingly antagonistic processes of nucleation and depolymerization are coordinated is not understood. Here, we reconstitute this coordination in vitro combining different pole-localized activities. We find that the spindle pole-localized kinesin-13 KIF2A is a microtubule minus-end depolymerase, in contrast to its paralog MCAK. Due to its asymmetric activity, KIF2A still allows microtubule nucleation from the γ-tubulin ring complex (γTuRC), which serves as a protective cap shielding the minus end against KIF2A binding. Efficient γTuRC uncapping requires the combined action of KIF2A and a microtubule severing enzyme, leading to treadmilling of the uncapped microtubule driven by KIF2A. Together, these results provide insight into the molecular mechanisms by which a minimal protein module coordinates microtubule nucleation and depolymerization at spindle poles consistent with their role in poleward microtubule flux.
Collapse
Affiliation(s)
- Gil Henkin
- Centre for Genomic Regulation(CRG), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - Cláudia Brito
- Centre for Genomic Regulation(CRG), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | | | - Thomas Surrey
- Centre for Genomic Regulation(CRG), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
- ICREA, Barcelona, Spain
| |
Collapse
|
4
|
Zhu Z, Becam I, Tovey CA, Elfarkouchi A, Yen EC, Bernard F, Guichet A, Conduit PT. Multifaceted modes of γ-tubulin complex recruitment and microtubule nucleation at mitotic centrosomes. J Cell Biol 2023; 222:e202212043. [PMID: 37698931 PMCID: PMC10497398 DOI: 10.1083/jcb.202212043] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 05/18/2023] [Accepted: 07/24/2023] [Indexed: 09/14/2023] Open
Abstract
Microtubule nucleation is mediated by γ-tubulin ring complexes (γ-TuRCs). In most eukaryotes, a GCP4/5/4/6 "core" complex promotes γ-tubulin small complex (γ-TuSC) association to generate cytosolic γ-TuRCs. Unlike γ-TuSCs, however, this core complex is non-essential in various species and absent from budding yeasts. In Drosophila, Spindle defective-2 (Spd-2) and Centrosomin (Cnn) redundantly recruit γ-tubulin complexes to mitotic centrosomes. Here, we show that Spd-2 recruits γ-TuRCs formed via the GCP4/5/4/6 core, but Cnn can recruit γ-TuSCs directly via its well-conserved CM1 domain, similar to its homologs in budding yeast. When centrosomes fail to recruit γ-tubulin complexes, they still nucleate microtubules via the TOG domain protein Mini-spindles (Msps), but these microtubules have different dynamic properties. Our data, therefore, help explain the dispensability of the GCP4/5/4/6 core and highlight the robustness of centrosomes as microtubule organizing centers. They also suggest that the dynamic properties of microtubules are influenced by how they are nucleated.
Collapse
Affiliation(s)
- Zihan Zhu
- Department of Zoology, University of Cambridge, Cambridge, UK
| | - Isabelle Becam
- Université Paris Cité, CNRS, Institut Jacques Monod, Paris, France
| | - Corinne A. Tovey
- Université Paris Cité, CNRS, Institut Jacques Monod, Paris, France
| | - Abir Elfarkouchi
- Université Paris Cité, CNRS, Institut Jacques Monod, Paris, France
| | - Eugenie C. Yen
- Department of Zoology, University of Cambridge, Cambridge, UK
| | - Fred Bernard
- Université Paris Cité, CNRS, Institut Jacques Monod, Paris, France
| | - Antoine Guichet
- Université Paris Cité, CNRS, Institut Jacques Monod, Paris, France
| | - Paul T. Conduit
- Department of Zoology, University of Cambridge, Cambridge, UK
- Université Paris Cité, CNRS, Institut Jacques Monod, Paris, France
| |
Collapse
|
5
|
Wang B, Liang Z, Tan T, Zhang M, Jiang Y, Shang Y, Gao X, Song S, Wang R, Chen H, Liu J, Li J, Ren Y, Liu P. CRB3 navigates Rab11 trafficking vesicles to promote γTuRC assembly during ciliogenesis. eLife 2023; 12:RP86689. [PMID: 37737843 PMCID: PMC10516600 DOI: 10.7554/elife.86689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/23/2023] Open
Abstract
The primary cilium plays important roles in regulating cell differentiation, signal transduction, and tissue organization. Dysfunction of the primary cilium can lead to ciliopathies and cancer. The formation and organization of the primary cilium are highly associated with cell polarity proteins, such as the apical polarity protein CRB3. However, the molecular mechanisms by which CRB3 regulates ciliogenesis and the location of CRB3 remain unknown. Here, we show that CRB3, as a navigator, regulates vesicle trafficking in γ-tubulin ring complex (γTuRC) assembly during ciliogenesis and cilium-related Hh and Wnt signaling pathways in tumorigenesis. Crb3 knockout mice display severe defects of the primary cilium in the mammary ductal lumen and renal tubule, while mammary epithelial-specific Crb3 knockout mice exhibit the promotion of ductal epithelial hyperplasia and tumorigenesis. CRB3 is essential for lumen formation and ciliary assembly in the mammary epithelium. We demonstrate that CRB3 localizes to the basal body and that CRB3 trafficking is mediated by Rab11-positive endosomes. Significantly, CRB3 interacts with Rab11 to navigate GCP6/Rab11 trafficking vesicles to CEP290, resulting in intact γTuRC assembly. In addition, CRB3-depleted cells are unresponsive to the activation of the Hh signaling pathway, while CRB3 regulates the Wnt signaling pathway. Therefore, our studies reveal the molecular mechanisms by which CRB3 recognizes Rab11-positive endosomes to facilitate ciliogenesis and regulates cilium-related signaling pathways in tumorigenesis.
Collapse
Affiliation(s)
- Bo Wang
- Center for Translational Medicine, the First Affiliated Hospital of Xi’an Jiaotong UniversityShaanxiChina
- Key Laboratory for Tumor Precision Medicine of Shaanxi Province, the First Affiliated Hospital of Xi’an Jiaotong UniversityShaanxiChina
| | - Zheyong Liang
- Center for Translational Medicine, the First Affiliated Hospital of Xi’an Jiaotong UniversityShaanxiChina
- Department of Cardiovascular Surgery, the First Affiliated Hospital of Xi’an Jiaotong UniversityShaanxiChina
| | - Tan Tan
- Center for Precision Medicine, Affiliated to the First People’s Hospital of Chenzhou, University of South ChinaChenzhouChina
| | - Miao Zhang
- Center for Translational Medicine, the First Affiliated Hospital of Xi’an Jiaotong UniversityShaanxiChina
- Key Laboratory for Tumor Precision Medicine of Shaanxi Province, the First Affiliated Hospital of Xi’an Jiaotong UniversityShaanxiChina
| | - Yina Jiang
- Department of Pathology, the First Affiliated Hospital of Xi’an Jiaotong UniversityShaanxiChina
| | - Yangyang Shang
- Center for Translational Medicine, the First Affiliated Hospital of Xi’an Jiaotong UniversityShaanxiChina
- Key Laboratory for Tumor Precision Medicine of Shaanxi Province, the First Affiliated Hospital of Xi’an Jiaotong UniversityShaanxiChina
| | - Xiaoqian Gao
- Center for Translational Medicine, the First Affiliated Hospital of Xi’an Jiaotong UniversityShaanxiChina
- Key Laboratory for Tumor Precision Medicine of Shaanxi Province, the First Affiliated Hospital of Xi’an Jiaotong UniversityShaanxiChina
| | - Shaoran Song
- Center for Translational Medicine, the First Affiliated Hospital of Xi’an Jiaotong UniversityShaanxiChina
- Key Laboratory for Tumor Precision Medicine of Shaanxi Province, the First Affiliated Hospital of Xi’an Jiaotong UniversityShaanxiChina
| | - Ruiqi Wang
- Center for Translational Medicine, the First Affiliated Hospital of Xi’an Jiaotong UniversityShaanxiChina
- Key Laboratory for Tumor Precision Medicine of Shaanxi Province, the First Affiliated Hospital of Xi’an Jiaotong UniversityShaanxiChina
| | - He Chen
- Center for Translational Medicine, the First Affiliated Hospital of Xi’an Jiaotong UniversityShaanxiChina
- Key Laboratory for Tumor Precision Medicine of Shaanxi Province, the First Affiliated Hospital of Xi’an Jiaotong UniversityShaanxiChina
| | - Jie Liu
- Center for Translational Medicine, the First Affiliated Hospital of Xi’an Jiaotong UniversityShaanxiChina
- Key Laboratory for Tumor Precision Medicine of Shaanxi Province, the First Affiliated Hospital of Xi’an Jiaotong UniversityShaanxiChina
| | - Juan Li
- Center for Translational Medicine, the First Affiliated Hospital of Xi’an Jiaotong UniversityShaanxiChina
- Key Laboratory for Tumor Precision Medicine of Shaanxi Province, the First Affiliated Hospital of Xi’an Jiaotong UniversityShaanxiChina
| | - Yu Ren
- Department of Breast Surgery, the First Affiliated Hospital of Xi’an Jiaotong UniversityShaanxiChina
| | - Peijun Liu
- Center for Translational Medicine, the First Affiliated Hospital of Xi’an Jiaotong UniversityShaanxiChina
- Key Laboratory for Tumor Precision Medicine of Shaanxi Province, the First Affiliated Hospital of Xi’an Jiaotong UniversityShaanxiChina
| |
Collapse
|
6
|
Lüders J. Microtubule cytoskeleton: The centrosome gains a membrane. Curr Biol 2023; 33:R180-R182. [PMID: 36917938 DOI: 10.1016/j.cub.2023.02.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023]
Abstract
Identification of a membrane structure, termed the 'centriculum', in Caenorhabditis elegans embryos challenges the textbook view of the centrosome - a major microtubule organizing center in animal cells - as an organelle that lacks a surrounding membrane.
Collapse
Affiliation(s)
- Jens Lüders
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, 08028 Barcelona, Spain.
| |
Collapse
|
7
|
He L, van Beem L, Snel B, Hoogenraad CC, Harterink M. PTRN-1 (CAMSAP) and NOCA-2 (NINEIN) are required for microtubule polarity in Caenorhabditis elegans dendrites. PLoS Biol 2022; 20:e3001855. [PMID: 36395330 PMCID: PMC9714909 DOI: 10.1371/journal.pbio.3001855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 12/01/2022] [Accepted: 09/27/2022] [Indexed: 11/18/2022] Open
Abstract
The neuronal microtubule cytoskeleton is key to establish axon-dendrite polarity. Dendrites are characterized by the presence of minus-end out microtubules. However, the mechanisms that organize these microtubules with the correct orientation are still poorly understood. Using Caenorhabditis elegans as a model system for microtubule organization, we characterized the role of 2 microtubule minus-end related proteins in this process, the microtubule minus-end stabilizing protein calmodulin-regulated spectrin-associated protein (CAMSAP/PTRN-1), and the NINEIN homologue, NOCA-2 (noncentrosomal microtubule array). We found that CAMSAP and NINEIN function in parallel to mediate microtubule organization in dendrites. During dendrite outgrowth, RAB-11-positive vesicles localized to the dendrite tip to nucleate microtubules and function as a microtubule organizing center (MTOC). In the absence of either CAMSAP or NINEIN, we observed a low penetrance MTOC vesicles mislocalization to the cell body, and a nearly fully penetrant phenotype in double mutant animals. This suggests that both proteins are important for localizing the MTOC vesicles to the growing dendrite tip to organize microtubules minus-end out. Whereas NINEIN localizes to the MTOC vesicles where it is important for the recruitment of the microtubule nucleator γ-tubulin, CAMSAP localizes around the MTOC vesicles and is cotranslocated forward with the MTOC vesicles upon dendritic growth. Together, these results indicate that microtubule nucleation from the MTOC vesicles and microtubule stabilization are both important to localize the MTOC vesicles distally to organize dendritic microtubules minus-end out.
Collapse
Affiliation(s)
- Liu He
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, Utrecht, the Netherlands
| | - Lotte van Beem
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, Utrecht, the Netherlands
| | - Berend Snel
- Theoretical Biology and Bioinformatics, Department of Biology, Faculty of Science, Utrecht University, Utrecht, the Netherlands
| | - Casper C. Hoogenraad
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, Utrecht, the Netherlands
- Department of Neuroscience, Genentech, Inc., South San Francisco, California, United States of America
| | - Martin Harterink
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, Utrecht, the Netherlands
- * E-mail:
| |
Collapse
|
8
|
Palacios Martínez S, Greaney J, Zenker J. Beyond the centrosome: The mystery of microtubule organising centres across mammalian preimplantation embryos. Curr Opin Cell Biol 2022; 77:102114. [PMID: 35841745 DOI: 10.1016/j.ceb.2022.102114] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 05/25/2022] [Accepted: 06/11/2022] [Indexed: 11/18/2022]
Abstract
Mammalian preimplantation embryogenesis depends on the spatio-temporal dynamics of the microtubule cytoskeleton to enable exceptionally fast changes in cell number, function, architecture, and fate. Microtubule organising centres (MTOCs), which coordinate the remodelling of microtubules, are therefore of fundamental significance during the first days of a new life. Despite its indispensable role during early mammalian embryogenesis, the origin of microtubule growth remains poorly understood. In this review, we summarise the most recent discoveries on microtubule organisation and function during early human embryogenesis and compare these to innovative studies conducted in alternative mammalian models. We emphasise the differences and analogies of centriole inheritance and their role during the first cleavage. Furthermore, we highlight the significance of non-centrosomal MTOCs for embryo viability and discuss the potential of novel in vitro models and light-inducible approaches towards unravelling microtubule formation in research and assisted reproductive technologies.
Collapse
Affiliation(s)
| | - Jessica Greaney
- Australian Regenerative Medicine Institute, Monash University, Clayton, Victoria, Australia
| | - Jennifer Zenker
- Australian Regenerative Medicine Institute, Monash University, Clayton, Victoria, Australia.
| |
Collapse
|
9
|
Wang X, Baumann C, De La Fuente R, Viveiros MM. Loss of acentriolar MTOCs disrupts spindle pole Aurora A and assembly of the liquid-like meiotic spindle domain in oocytes. J Cell Sci 2021; 134:jcs256297. [PMID: 34152366 PMCID: PMC8325960 DOI: 10.1242/jcs.256297] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 06/14/2021] [Indexed: 11/20/2022] Open
Abstract
Oocyte-specific knockdown of pericentrin (PCNT) in transgenic (Tg) mice disrupts acentriolar microtubule-organizing center (aMTOC) formation, leading to spindle instability and error-prone meiotic division. Here, we show that PCNT-depleted oocytes lack phosphorylated Aurora A (pAURKA) at spindle poles, while overall levels are unaltered. To test aMTOC-associated AURKA function, metaphase II (MII) control (WT) and Tg oocytes were briefly exposed to a specific AURKA inhibitor (MLN8237). Similar defects were observed in Tg and MLN8237-treated WT oocytes, including altered spindle structure, increased chromosome misalignment and impaired microtubule regrowth. Yet, AURKA inhibition had a limited effect on Tg oocytes, revealing a critical role for aMTOC-associated AURKA in regulating spindle stability. Notably, spindle instability was associated with disrupted γ-tubulin and lack of the liquid-like meiotic spindle domain (LISD) in Tg oocytes. Analysis of this Tg model provides the first evidence that LISD assembly depends expressly on aMTOC-associated AURKA, and that Ran-mediated spindle formation ensues without the LISD. These data support that loss of aMTOC-associated AURKA and failure of LISD assembly contribute to error-prone meiotic division in PCNT-depleted oocytes, underscoring the essential role of aMTOCs for spindle stability.
Collapse
Affiliation(s)
- Xiaotian Wang
- Department of Physiology and Pharmacology, College of Veterinary Medicine, University of Georgia,Athens, GA 30602, USA
| | - Claudia Baumann
- Department of Physiology and Pharmacology, College of Veterinary Medicine, University of Georgia,Athens, GA 30602, USA
| | - Rabindranath De La Fuente
- Department of Physiology and Pharmacology, College of Veterinary Medicine, University of Georgia,Athens, GA 30602, USA
- Regenerative Biosciences Center (RBC), University of Georgia,Athens, GA 30602, USA
| | - Maria M. Viveiros
- Department of Physiology and Pharmacology, College of Veterinary Medicine, University of Georgia,Athens, GA 30602, USA
- Regenerative Biosciences Center (RBC), University of Georgia,Athens, GA 30602, USA
| |
Collapse
|
10
|
Sanchez AD, Branon TC, Cote LE, Papagiannakis A, Liang X, Pickett MA, Shen K, Jacobs-Wagner C, Ting AY, Feldman JL. Proximity labeling reveals non-centrosomal microtubule-organizing center components required for microtubule growth and localization. Curr Biol 2021; 31:3586-3600.e11. [PMID: 34242576 DOI: 10.1016/j.cub.2021.06.021] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 04/13/2021] [Accepted: 06/09/2021] [Indexed: 12/24/2022]
Abstract
Microtubules are polarized intracellular polymers that play key roles in the cell, including in transport, polarity, and cell division. Across eukaryotic cell types, microtubules adopt diverse intracellular organization to accommodate these distinct functions coordinated by specific cellular sites called microtubule-organizing centers (MTOCs). Over 50 years of research on MTOC biology has focused mainly on the centrosome; however, most differentiated cells employ non-centrosomal MTOCs (ncMTOCs) to organize their microtubules into diverse arrays, which are critical to cell function. To identify essential ncMTOC components, we developed the biotin ligase-based, proximity-labeling approach TurboID for use in C. elegans. We identified proteins proximal to the microtubule minus end protein PTRN-1/Patronin at the apical ncMTOC of intestinal epithelial cells, focusing on two conserved proteins: spectraplakin protein VAB-10B/MACF1 and WDR-62, a protein we identify as homologous to vertebrate primary microcephaly disease protein WDR62. VAB-10B and WDR-62 do not associate with the centrosome and instead specifically regulate non-centrosomal microtubules and the apical targeting of microtubule minus-end proteins. Depletion of VAB-10B resulted in microtubule mislocalization and delayed localization of a microtubule nucleation complex ɣ-tubulin ring complex (γ-TuRC), while loss of WDR-62 decreased the number of dynamic microtubules and abolished γ-TuRC localization. This regulation occurs downstream of cell polarity and in conjunction with actin. As this is the first report for non-centrosomal roles of WDR62 family proteins, we expand the basic cell biological roles of this important disease protein. Our studies identify essential ncMTOC components and suggest a division of labor where microtubule growth and localization are distinctly regulated.
Collapse
Affiliation(s)
- Ariana D Sanchez
- Department of Biology, Stanford University, 371 Serra Mall, Stanford, CA 94305, USA
| | - Tess C Branon
- Department of Biology, Stanford University, 371 Serra Mall, Stanford, CA 94305, USA; Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA; Departments of Genetics and Chemistry, Stanford University, Stanford, CA, USA
| | - Lauren E Cote
- Department of Biology, Stanford University, 371 Serra Mall, Stanford, CA 94305, USA
| | | | - Xing Liang
- Department of Biology, Stanford University, 371 Serra Mall, Stanford, CA 94305, USA; Howard Hughes Medical Institute, Stanford University, Stanford, CA, USA
| | - Melissa A Pickett
- Department of Biology, Stanford University, 371 Serra Mall, Stanford, CA 94305, USA
| | - Kang Shen
- Department of Biology, Stanford University, 371 Serra Mall, Stanford, CA 94305, USA; Howard Hughes Medical Institute, Stanford University, Stanford, CA, USA
| | - Christine Jacobs-Wagner
- Howard Hughes Medical Institute, Stanford University, Stanford, CA, USA; Department of Biology and ChEM-H Institute, Stanford University, Stanford, CA, USA
| | - Alice Y Ting
- Department of Biology, Stanford University, 371 Serra Mall, Stanford, CA 94305, USA; Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA; Departments of Genetics and Chemistry, Stanford University, Stanford, CA, USA; Chan Zuckerberg Biohub, San Francisco, CA, USA
| | - Jessica L Feldman
- Department of Biology, Stanford University, 371 Serra Mall, Stanford, CA 94305, USA.
| |
Collapse
|
11
|
Brilot AF, Lyon AS, Zelter A, Viswanath S, Maxwell A, MacCoss MJ, Muller EG, Sali A, Davis TN, Agard DA. CM1-driven assembly and activation of yeast γ-tubulin small complex underlies microtubule nucleation. eLife 2021; 10:e65168. [PMID: 33949948 PMCID: PMC8099430 DOI: 10.7554/elife.65168] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Accepted: 04/12/2021] [Indexed: 01/08/2023] Open
Abstract
Microtubule (MT) nucleation is regulated by the γ-tubulin ring complex (γTuRC), conserved from yeast to humans. In Saccharomyces cerevisiae, γTuRC is composed of seven identical γ-tubulin small complex (γTuSC) sub-assemblies, which associate helically to template MT growth. γTuRC assembly provides a key point of regulation for the MT cytoskeleton. Here, we combine crosslinking mass spectrometry, X-ray crystallography, and cryo-EM structures of both monomeric and dimeric γTuSCs, and open and closed helical γTuRC assemblies in complex with Spc110p to elucidate the mechanisms of γTuRC assembly. γTuRC assembly is substantially aided by the evolutionarily conserved CM1 motif in Spc110p spanning a pair of adjacent γTuSCs. By providing the highest resolution and most complete views of any γTuSC assembly, our structures allow phosphorylation sites to be mapped, surprisingly suggesting that they are mostly inhibitory. A comparison of our structures with the CM1 binding site in the human γTuRC structure at the interface between GCP2 and GCP6 allows for the interpretation of significant structural changes arising from CM1 helix binding to metazoan γTuRC.
Collapse
Affiliation(s)
- Axel F Brilot
- Department of Biochemistry and Biophysics, University of California at San FranciscoSan FranciscoUnited States
| | - Andrew S Lyon
- Department of Biochemistry and Biophysics, University of California at San FranciscoSan FranciscoUnited States
| | - Alex Zelter
- Department of Biochemistry, University of WashingtonSeattleUnited States
| | - Shruthi Viswanath
- Department of Bioengineering and Therapeutic Sciences, University of California at San FranciscoSan FranciscoUnited States
| | - Alison Maxwell
- Department of Biochemistry and Biophysics, University of California at San FranciscoSan FranciscoUnited States
| | - Michael J MacCoss
- Department of Genome Sciences, University of WashingtonSeattleUnited States
| | - Eric G Muller
- Department of Biochemistry, University of WashingtonSeattleUnited States
| | - Andrej Sali
- Department of Bioengineering and Therapeutic Sciences, University of California at San FranciscoSan FranciscoUnited States
| | - Trisha N Davis
- Department of Biochemistry, University of WashingtonSeattleUnited States
| | - David A Agard
- Department of Biochemistry and Biophysics, University of California at San FranciscoSan FranciscoUnited States
| |
Collapse
|
12
|
Friedman D, Simmonds P, Hale A, Bere L, Hodson NW, White MRH, Davis DM. Natural killer cell immune synapse formation and cytotoxicity are controlled by tension of the target interface. J Cell Sci 2021; 134:jcs258570. [PMID: 33712452 PMCID: PMC8077183 DOI: 10.1242/jcs.258570] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 03/03/2021] [Indexed: 12/11/2022] Open
Abstract
Natural killer (NK) cells can kill infected or transformed cells via a lytic immune synapse. Diseased cells may exhibit altered mechanical properties but how this impacts NK cell responsiveness is unknown. We report that human NK cells were stimulated more effectively to secrete granzymes A and B, FasL (also known as FasLG), granulysin and IFNγ, by stiff (142 kPa) compared to soft (1 kPa) planar substrates. To create surrogate spherical targets of defined stiffness, sodium alginate was used to synthesise soft (9 kPa), medium (34 kPa) or stiff (254 kPa) cell-sized beads, coated with antibodies against activating receptor NKp30 (also known as NCR3) and the integrin LFA-1 (also known as ITGAL). Against stiff beads, NK cells showed increased degranulation. Polarisation of the microtubule-organising centre and lytic granules were impaired against soft targets, which instead resulted in the formation of unstable kinapses. Thus, by varying target stiffness to characterise the mechanosensitivity of immune synapses, we identify soft targets as a blind spot in NK cell recognition. This article has an associated First Person interview with the co-first authors of the paper.
Collapse
Affiliation(s)
- Daniel Friedman
- The Lydia Becker Institute, Faculty of Biology, Medicine and Health, University of Manchester, Core Technology Facility building, 46 Grafton Street, Manchester M13 9NT, United Kingdom
| | - Poppy Simmonds
- The Lydia Becker Institute, Faculty of Biology, Medicine and Health, University of Manchester, Core Technology Facility building, 46 Grafton Street, Manchester M13 9NT, United Kingdom
| | - Alexander Hale
- The Lydia Becker Institute, Faculty of Biology, Medicine and Health, University of Manchester, Core Technology Facility building, 46 Grafton Street, Manchester M13 9NT, United Kingdom
| | - Leoma Bere
- The Lydia Becker Institute, Faculty of Biology, Medicine and Health, University of Manchester, Core Technology Facility building, 46 Grafton Street, Manchester M13 9NT, United Kingdom
| | - Nigel W. Hodson
- BioAFM Facility, Faculty of Biology, Medicine and Health, Stopford Building, University of Manchester, Oxford Road, Manchester M13 9PT, United Kingdom
| | - Michael R. H. White
- Michael Smith Building, Faculty of Life Sciences, University of Manchester, Manchester M13 9PT, United Kingdom
| | - Daniel M. Davis
- The Lydia Becker Institute, Faculty of Biology, Medicine and Health, University of Manchester, Core Technology Facility building, 46 Grafton Street, Manchester M13 9NT, United Kingdom
| |
Collapse
|
13
|
Abstract
The native γ-tubulin ring complex is an asymmetric, imperfect template for microtubule nucleation. Wieczorek et al. (2021. J. Cell Biol.https://doi.org/10.1083/jcb.202009146) and Zimmermann et al. (2020. Sci. Adv.https://doi.org/10.1126/sciadv.abe0894) have reconstituted a recombinant complex that allows study of structure-function relationships and regulatory mechanisms.
Collapse
Affiliation(s)
- Andreas Merdes
- Centre de Biologie Intégrative, Université Paul Sabatier/Centre National de la Recherche Scientifique, Toulouse, France
| |
Collapse
|
14
|
Dundon SER, Pollard TD. Microtubule nucleation promoters Mto1 and Mto2 regulate cytokinesis in fission yeast. Mol Biol Cell 2020; 31:1846-1856. [PMID: 32520628 PMCID: PMC7525812 DOI: 10.1091/mbc.e19-12-0686] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 05/26/2020] [Accepted: 06/04/2020] [Indexed: 01/16/2023] Open
Abstract
Microtubules of the mitotic spindle direct cytokinesis in metazoans but this has not been documented in fungi. We report evidence that microtubule nucleators at the spindle pole body help coordinate cytokinetic furrow formation in fission yeast. The temperature-sensitive cps1-191 strain (Liu et al., 1999) with a D277N substitution in β-glucan synthase 1 (Cps1/Bgs1) was reported to arrest with an unconstricted contractile ring. We discovered that contractile rings in cps1-191 cells constrict slowly and that an mto2S338N mutation is required with the bgs1D277Nmutation to reproduce the cps1-191 phenotype. Complexes of Mto2 and Mto1 with γ-tubulin regulate microtubule assembly. Deletion of Mto1 along with the bgs1D277N mutation also gives the cps1-191 phenotype, which is not observed in mto2S338N or mto1Δ cells expressing bgs1+. Both mto2S338N and mto1Δ cells nucleate fewer astral microtubules than normal and have higher levels of Rho1-GTP at the division site than wild-type cells. We report multiple conditions that sensitize mto1Δ and mto2S338N cells to furrow ingression phenotypes.
Collapse
Affiliation(s)
- Samantha E. R. Dundon
- Departments of Molecular Cellular and Developmental Biology, Yale University, New Haven, CT 06520-8103
| | - Thomas D. Pollard
- Departments of Molecular Cellular and Developmental Biology, Yale University, New Haven, CT 06520-8103
- Departments of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520-8103
- Department of Cell Biology, Yale University, New Haven, CT 06520-8103
| |
Collapse
|
15
|
Chuang CH, Schlientz AJ, Yang J, Bowerman B. Microtubule assembly and pole coalescence: early steps in Caenorhabditiselegans oocyte meiosis I spindle assembly. Biol Open 2020; 9:bio052308. [PMID: 32493729 PMCID: PMC7328010 DOI: 10.1242/bio.052308] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Accepted: 05/11/2020] [Indexed: 12/17/2022] Open
Abstract
How oocytes assemble bipolar meiotic spindles in the absence of centrosomes as microtubule organizing centers remains poorly understood. We have used live cell imaging in Caenorhabditis elegans to investigate requirements for the nuclear lamina and for conserved regulators of microtubule dynamics during oocyte meiosis I spindle assembly, assessing these requirements with respect to recently identified spindle assembly steps. We show that the nuclear lamina is required for microtubule bundles to form a peripheral cage-like structure that appears shortly after oocyte nuclear envelope breakdown and surrounds the oocyte chromosomes, although bipolar spindles still assembled in its absence. Although two conserved regulators of microtubule nucleation, RAN-1 and γ-tubulin, are not required for bipolar spindle assembly, both contribute to normal levels of spindle-associated microtubules and spindle assembly dynamics. Finally, the XMAP215 ortholog ZYG-9 and the nearly identical minus-end directed kinesins KLP-15/16 are required for proper assembly of the early cage-like structure of microtubule bundles, and for early spindle pole foci to coalesce into a bipolar structure. Our results provide a framework for assigning molecular mechanisms to recently described steps in C. elegans oocyte meiosis I spindle assembly.
Collapse
Affiliation(s)
- Chien-Hui Chuang
- Institute of Molecular Biology and Department of Biology, 1229 University of Oregon, Eugene, Oregon 97403, USA
| | - Aleesa J Schlientz
- Institute of Molecular Biology and Department of Biology, 1229 University of Oregon, Eugene, Oregon 97403, USA
| | - Jie Yang
- Institute of Molecular Biology and Department of Biology, 1229 University of Oregon, Eugene, Oregon 97403, USA
| | - Bruce Bowerman
- Institute of Molecular Biology and Department of Biology, 1229 University of Oregon, Eugene, Oregon 97403, USA
| |
Collapse
|
16
|
Wang H, Choe MH, Lee IW, Namgoong S, Kim JS, Kim NH, Oh JS. CIP2A acts as a scaffold for CEP192-mediated microtubule organizing center assembly by recruiting Plk1 and aurora A during meiotic maturation. Development 2017; 144:3829-3839. [PMID: 28935709 DOI: 10.1242/dev.158584] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 09/06/2017] [Indexed: 12/16/2023]
Abstract
In somatic cells spindle microtubules are nucleated from centrosomes that act as major microtubule organizing centers (MTOCs), whereas oocytes form meiotic spindles by assembling multiple acentriolar MTOCs without canonical centrosomes. Aurora A and Plk1 are required for these events, but the underlying mechanisms remain largely unknown. Here we show that CIP2A regulates MTOC organization by recruiting aurora A and Plk1 at spindle poles during meiotic maturation. CIP2A colocalized with pericentrin at spindle poles with a few distinct cytoplasmic foci. Although CIP2A has been identified as an endogenous inhibitor of protein phosphatase 2A (PP2A), overexpression of CIP2A had no effect on meiotic maturation. Depletion of CIP2A perturbed normal spindle organization and chromosome alignment by impairing MTOC organization. Importantly, CIP2A was reciprocally associated with CEP192, promoting recruitment of aurora A and Plk1 at MTOCs. CIP2A was phosphorylated by Plk1 at S904, which targets CIP2A to MTOCs and facilitates MTOC organization with CEP192. Our results suggest that CIP2A acts as a scaffold for CEP192-mediated MTOC assembly by recruiting Plk1 and aurora A during meiotic maturation in mouse oocytes.
Collapse
Affiliation(s)
- HaiYang Wang
- Department of Animal Sciences, Chungbuk National University, Cheongju 28644, Korea
| | - Min Ho Choe
- Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul 01812, Korea
- Department of Life Sciences and Biotechnology, College of Life Science and Biotechnology, Korea University, Seoul 02841, Korea
| | - In-Won Lee
- Department of Animal Sciences, Chungbuk National University, Cheongju 28644, Korea
| | - Suk Namgoong
- Department of Animal Sciences, Chungbuk National University, Cheongju 28644, Korea
| | - Jae-Sung Kim
- Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul 01812, Korea
| | - Nam-Hyung Kim
- Department of Animal Sciences, Chungbuk National University, Cheongju 28644, Korea
| | - Jeong Su Oh
- Department of Genetic Engineering, College of Biotechnology and Bioengineering, Sungkyunkwan University, Suwon 16419, Korea
| |
Collapse
|
17
|
Khan SN, Shaeib F, Thakur M, Jeelani R, Awonuga AO, Goud PT, Abu-Soud HM. Peroxynitrite deteriorates oocyte quality through disassembly of microtubule organizing centers. Free Radic Biol Med 2016; 91:275-80. [PMID: 26746586 DOI: 10.1016/j.freeradbiomed.2015.12.033] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Revised: 12/23/2015] [Accepted: 12/29/2015] [Indexed: 11/24/2022]
Abstract
Previous theoretical studies have suggested that utilization of 3-D imaging to acquire morphologic parameters of meiotic spindles may be useful in infertility related procedures as an assessment of oocyte quality. However, our results show that treatment of oocytes with increasing concentrations of peroxynitrite (ONOO(-)) caused a dramatic alteration in spindle shape in which morphologic parameters are not measurable or are uninformative in terms of oocyte quality. Metaphase II mouse oocytes (n=520) were treated with increasing concentrations of ONOO(-), after which all oocytes were fixed and subjected to indirect immunofluorescence. Oocyte quality was assessed by alterations in the microtubule-organizing center (MTOC), pericentrin location, microtubule morphology, and chromosomal alignment. In untreated oocytes, pericentrin is primarily assembled utilizing the acentrosomal MTOC, which appears as a condensation at both spindle poles. The spindle has a symmetrical pointed barrel shape, assembled around the chromosomal plate at the spindle equator. Oocytes treated with low concentrations of ONOO(-) (<2.5 μM) showed shortening of the spindle apparatus, while pericentrin scatters from a tight condensation to a dispersed cluster around each spindle pole. At higher ONOO(-) concentrations (>2.5μM) the central attachments between microtubules are strained and bend or unevenly break, and the MTOC proteins are further dispersed or undetectable. Peroxynitrite mediated MTOC damage, which deranges the chromosomal scaffold at the time of assembly and separation, caused the deterioration in oocyte quality. These results provide a link between reactive oxygen species and poor reproductive outcomes and elucidate the underlying etiology, which could be used as a superior biomarker for oocyte quality compared to existing assessment tools.
Collapse
Affiliation(s)
- Sana N Khan
- Department of Obstetrics and Gynecology, The C.S. Mott Center for Human Growth and Development, Wayne State University School of Medicine, Detroit, MI, USA
| | - Faten Shaeib
- Department of Obstetrics and Gynecology, The C.S. Mott Center for Human Growth and Development, Wayne State University School of Medicine, Detroit, MI, USA
| | - Mili Thakur
- Department of Obstetrics and Gynecology, The C.S. Mott Center for Human Growth and Development, Wayne State University School of Medicine, Detroit, MI, USA
| | - Roohi Jeelani
- Department of Obstetrics and Gynecology, The C.S. Mott Center for Human Growth and Development, Wayne State University School of Medicine, Detroit, MI, USA
| | - Awoniyi O Awonuga
- Department of Obstetrics and Gynecology, The C.S. Mott Center for Human Growth and Development, Wayne State University School of Medicine, Detroit, MI, USA
| | - Pravin T Goud
- Department of Obstetrics and gynecology, Division of Reproductive Endocrinology and Infertility, University of California Davis, Sacramento, CA, USA; California IVF Fertility Center, Davis and Sacramento, USA
| | - Husam M Abu-Soud
- Department of Obstetrics and Gynecology, The C.S. Mott Center for Human Growth and Development, Wayne State University School of Medicine, Detroit, MI, USA; Department of Biochemistry and Molecular Biology, Wayne State University School of Medicine, Detroit, MI 48202, USA.
| |
Collapse
|
18
|
Baumbach J, Novak ZA, Raff JW, Wainman A. Dissecting the function and assembly of acentriolar microtubule organizing centers in Drosophila cells in vivo. PLoS Genet 2015; 11:e1005261. [PMID: 26020779 PMCID: PMC4447278 DOI: 10.1371/journal.pgen.1005261] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Accepted: 05/04/2015] [Indexed: 11/18/2022] Open
Abstract
Acentriolar microtubule organizing centers (aMTOCs) are formed during meiosis and mitosis in several cell types, but their function and assembly mechanism is unclear. Importantly, aMTOCs can be overactive in cancer cells, enhancing multipolar spindle formation, merotelic kinetochore attachment and aneuploidy. Here we show that aMTOCs can form in acentriolar Drosophila somatic cells in vivo via an assembly pathway that depends on Asl, Cnn and, to a lesser extent, Spd-2--the same proteins that appear to drive mitotic centrosome assembly in flies. This finding enabled us to ablate aMTOC formation in acentriolar cells, and so perform a detailed genetic analysis of the contribution of aMTOCs to acentriolar mitotic spindle formation. Here we show that although aMTOCs can nucleate microtubules, they do not detectably increase the efficiency of acentriolar spindle assembly in somatic fly cells. We find that they are required, however, for robust microtubule array assembly in cells without centrioles that also lack microtubule nucleation from around the chromatin. Importantly, aMTOCs are also essential for dynein-dependent acentriolar spindle pole focusing and for robust cell proliferation in the absence of centrioles and HSET/Ncd (a kinesin essential for acentriolar spindle pole focusing in many systems). We propose an updated model for acentriolar spindle pole coalescence by the molecular motors Ncd/HSET and dynein in conjunction with aMTOCs.
Collapse
Affiliation(s)
- Janina Baumbach
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Zsofia Anna Novak
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Jordan W. Raff
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Alan Wainman
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
- * E-mail:
| |
Collapse
|
19
|
Uzbekov RE, Alieva IB. [The centrosome--a riddle of the "cell processor"]. Tsitologiia 2008; 50:91-112. [PMID: 18540189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
In the present review the description of history of the centrosome investigation is given and the current state of knowledge of this cellular structure in morphological, biochemical, and functional aspects is presented. Besides of the classical functions of the centrosome as a MT nucleating, MT ancoriging, and MT organizing center, the idea about the centrosome as a cellular regulating center and as a structural part of the mechanism operating dynamic morphology of a cell is discussed.
Collapse
|
20
|
Abstract
Centrosomes consist of two centrioles surrounded by an amorphous pericentriolar matrix (PCM), but it is unknown how centrioles and PCM are connected. We show that the centrioles in Drosophila embryos that lack the centrosomal protein Centrosomin (Cnn) can recruit PCM components but cannot maintain a proper attachment to the PCM. As a result, the centrioles “rocket” around in the embryo and often lose their connection to the nucleus in interphase and to the spindle poles in mitosis. This leads to severe mitotic defects in embryos and to errors in centriole segregation in somatic cells. The Cnn-related protein CDK5RAP2 is linked to microcephaly in humans, but cnn mutant brains are of normal size, and we observe only subtle defects in the asymmetric divisions of mutant neuroblasts. We conclude that Cnn maintains the proper connection between the centrioles and the PCM; this connection is required for accurate centriole segregation in somatic cells but is not essential for the asymmetric division of neuroblasts.
Collapse
Affiliation(s)
- Eliana P Lucas
- Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge CB2 1QN, England, UK
| | | |
Collapse
|
21
|
Efimov A, Kharitonov A, Efimova N, Loncarek J, Miller PM, Andreyeva N, Gleeson P, Galjart N, Maia ARR, McLeod IX, Yates JR, Maiato H, Khodjakov A, Akhmanova A, Kaverina I. Asymmetric CLASP-dependent nucleation of noncentrosomal microtubules at the trans-Golgi network. Dev Cell 2007; 12:917-30. [PMID: 17543864 PMCID: PMC2705290 DOI: 10.1016/j.devcel.2007.04.002] [Citation(s) in RCA: 379] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2006] [Revised: 03/05/2007] [Accepted: 04/05/2007] [Indexed: 10/23/2022]
Abstract
Proper organization of microtubule arrays is essential for intracellular trafficking and cell motility. It is generally assumed that most if not all microtubules in vertebrate somatic cells are formed by the centrosome. Here we demonstrate that a large number of microtubules in untreated human cells originate from the Golgi apparatus in a centrosome-independent manner. Both centrosomal and Golgi-emanating microtubules need gamma-tubulin for nucleation. Additionally, formation of microtubules at the Golgi requires CLASPs, microtubule-binding proteins that selectively coat noncentrosomal microtubule seeds. We show that CLASPs are recruited to the trans-Golgi network (TGN) at the Golgi periphery by the TGN protein GCC185. In sharp contrast to radial centrosomal arrays, microtubules nucleated at the peripheral Golgi compartment are preferentially oriented toward the leading edge in motile cells. We propose that Golgi-emanating microtubules contribute to the asymmetric microtubule networks in polarized cells and support diverse processes including post-Golgi transport to the cell front.
Collapse
Affiliation(s)
- Andrey Efimov
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, TN 37232-8240, USA
| | | | - Nadia Efimova
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, TN 37232-8240, USA
| | - Jadranka Loncarek
- Wadsworth Center, New York State Department of Health, Albany, NY 12201-0509, USA
| | - Paul M. Miller
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, TN 37232-8240, USA
| | | | - Paul Gleeson
- Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Vic 3010, Australia
| | - Niels Galjart
- Department of Cell Biology and Genetics, Erasmus MC, 3000 DR Rotterdam, The Netherlands
| | - Ana R. R. Maia
- Institute for Molecular Cell Biology & Laboratory of Molecular and Cell Biology, Faculdade de Medicine, University Porto, 4050-345 Porto, Portugal
| | - Ian X. McLeod
- Department of Cell Biology, Scripps Research Institute, La Jolla, CA 93037, USA
| | - John R. Yates
- Department of Cell Biology, Scripps Research Institute, La Jolla, CA 93037, USA
| | - Helder Maiato
- Institute for Molecular Cell Biology & Laboratory of Molecular and Cell Biology, Faculdade de Medicine, University Porto, 4050-345 Porto, Portugal
| | - Alexey Khodjakov
- Wadsworth Center, New York State Department of Health, Albany, NY 12201-0509, USA
| | - Anna Akhmanova
- Department of Cell Biology and Genetics, Erasmus MC, 3000 DR Rotterdam, The Netherlands
| | - Irina Kaverina
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, TN 37232-8240, USA
- corresponding author, ; phone: (615)-936 5567; fax: (615)-936 5673
| |
Collapse
|
22
|
Haren L, Bazin I, Rémy MH. [NEDD1 and microtubule nucleation complexes: To recruit for better organizing]. Med Sci (Paris) 2006; 22:804-6. [PMID: 17026925 DOI: 10.1051/medsci/20062210804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
23
|
Gundersen GG, Wen Y, Eng CH, Schmoranzer J, Cabrera-Poch N, Morris EJS, Chen M, Gomes ER. Regulation of microtubules by Rho GTPases in migrating cells. Novartis Found Symp 2005; 269:106-16; discussion 116-26, 223-30. [PMID: 16358406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Microtubules (MTs) contribute to cell polarization and migration, but the molecular mechanism involved are unknown. We have explored signalling pathways that generate specific changes in MTs arrays in wounded monolayers of fibroblasts. In earlier work, we found that Rho GTPase and its effector mDia, stimulate selective MT stabilization in the lamella, whereas Cdc42 and the MT motor protein dynein regulate MT organizing centre (MTOC) reorientation towards the leading edge. We have now found that the MT tip proteins EB1 and adenomatous polyposis coli protein (APC) function with mDia to stabilize MTs and interact directly with mDia. EB1, APC and mDia localize to the ends of stabilized MTs suggesting that they may contribute to capping of these MTs. Models of MTOC reorientation suggest that the MTOC moves in front of the nucleus by dynein pulling on MTs. In contrast, we find by directly imaging MTOC reorientation that the nucleus moves rearward while the MTOC remains stationary. Rearward nuclear movement is coupled to retrograde actin-myosin flow and is regulated by Cdc42 and its effector myotonic dystrophy kinase-related Cdc42-binding kinase. Dynein is not involved in nuclear movement, but is essential to maintain the MTOC at the cell centroid. These results show that there are two Cdc42 pathways that regulate MTOC reorientation.
Collapse
|
24
|
Abstract
The early embryogenesis and cell lineage of the pinewood nematode Bursaphelenchus xylophilus was followed from a single-cell zygote to a 46-cell embryo under Nomarski optics, and elongation of the microtubules was studied by immunostaining. As a B. xylophilus oocyte matures, it passes through a passage connecting the oviduct with the quadricolumella, the distal part of the uterus, and reaches the quadricolumella where it stays for a few minutes and is fertilized. After fertilization, the germinal vesicle disappears, an eggshell is formed, and the male and female pronuclei appear. The pronuclei move toward each other and fuse at the center of the egg. Around this time, the microtubule-organizing center appears. The presumptive region of sperm entry into the oocyte becomes the future anterior portion of the embryo. This anterior-posterior axis determination is opposite to that of Caenorhabditis elegans, where the sperm entry site becomes the posterior portion of the embryo. The optimal growth temperatures of these two nematodes also differ in that temperatures of about 30 degrees C afford the fastest growth rate and highest hatching frequency in B. xylophilus. Otherwise, the lineage resembles that of C. elegans with respect to timing, positioning and the axis orientation of each cell division.
Collapse
Affiliation(s)
- Koichi Hasegawa
- Institute for Biological Function, Chubu University, 1200 Matsumoto-cho, Kasugai 487-8501, Japan
| | | | | | | |
Collapse
|
25
|
Grieshaber SS, Grieshaber NA, Hackstadt T. Chlamydia trachomatis uses host cell dynein to traffic to the microtubule-organizing center in a p50 dynamitin-independent process. J Cell Sci 2003; 116:3793-802. [PMID: 12902405 DOI: 10.1242/jcs.00695] [Citation(s) in RCA: 143] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Chlamydiae are pathogenic obligate intracellular bacteria with a biphasic developmental cycle that involves cell types adapted for extracellular survival (elementary bodies, EBs) and intracellular multiplication (reticulate bodies, RBs). The intracellular development of chlamydiae occurs entirely within a membrane-bound vacuole termed an inclusion. Within 2 hours after entry into host cells, Chlamydia trachomatis EBs are trafficked to the perinuclear region of the host cell and remain in close proximity to the Golgi apparatus, where they begin to fuse with a subset of host vesicles containing sphingomyelin. Here, we provide evidence that chlamydial migration from the cell periphery to the peri-Golgi region resembles host cell vesicular trafficking. Chlamydiae move towards the minus end of microtubules and aggregate at the microtubule-organizing center (MTOC). In mammalian cells the most important minus-end-directed microtubule motor is cytoplasmic dynein. Microinjection of antibodies to a subunit of cytoplasmic dynein inhibited movement of chlamydiae to the MTOC, whereas microinjection of antibodies to the plus-directed microtubule motor, kinesin, had no effect. Surprisingly, overexpression of the protein p50 dynamitin, a subunit of the dynactin complex that links vesicular cargo to the dynein motor in minus directed vesicle trafficking, did not abrogate chlamydial migration even though host vesicle transport was inhibited. Nascent chlamydial inclusions did, however, colocalize with the p150(Glued) dynactin subunit, which suggests that p150(Glued) may be required for dynein activation or processivity but that the cargo-binding activity of dynactin, supplied by p50 dynamitin subunits and possibly other subunits, is not. Because chlamydial transcription and translation were required for this intracellular trafficking, chlamydial proteins modifying the cytoplasmic face of the inclusion membrane are probable candidates for proteins fulfilling this function.
Collapse
Affiliation(s)
- Scott S Grieshaber
- Host-Parasite Interactions Section, Laboratory of Intracellular Parasites, NIAID, NIH, Rocky Mountain Laboratories, Hamilton, MT 59840, USA
| | | | | |
Collapse
|
26
|
Petit C, Giron ML, Tobaly-Tapiero J, Bittoun P, Real E, Jacob Y, Tordo N, De The H, Saib A. Targeting of incoming retroviral Gag to the centrosome involves a direct interaction with the dynein light chain 8. J Cell Sci 2003; 116:3433-42. [PMID: 12857789 DOI: 10.1242/jcs.00613] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The role of cellular proteins in the replication of retroviruses, especially during virus assembly, has been partly unraveled by recent studies. Paradoxically, little is known about the route taken by retroviruses to reach the nucleus at the early stages of infection. To get insight into this stage of virus replication, we have studied the trafficking of foamy retroviruses and have previously shown that incoming viral proteins reach the microtubule organizing center (MTOC) prior to nuclear translocation of the viral genome. Here, we show that incoming viruses concentrate around the MTOC as free and structured capsids. Interestingly, the Gag protein, the scaffold component of viral capsids, targets the pericentrosomal region in transfected cells in the absence of any other viral components but in a microtubule- and dynein/dynactin-dependent manner. Trafficking of Gag towards the centrosome requires a minimal 30 amino acid coiled-coil motif in the N-terminus of the molecule. Finally, we describe a direct interaction between Gag and dynein light chain 8 that probably accounts for the specific routing of the incoming capsids to the centrosome prior to nuclear import of the viral genome.
Collapse
Affiliation(s)
- Coralie Petit
- CNRS UPR9051, Hôpital Saint-Louis, Conventionné par l'Université Paris 7, 1 avenue Claude Vellefaux, 75475 Paris Cedex 10, France
| | | | | | | | | | | | | | | | | |
Collapse
|
27
|
Glotzer JB, Michou AI, Baker A, Saltik M, Cotten M. Microtubule-independent motility and nuclear targeting of adenoviruses with fluorescently labeled genomes. J Virol 2001; 75:2421-34. [PMID: 11160745 PMCID: PMC114825 DOI: 10.1128/jvi.75.5.2421-2434.2001] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
A novel adenovirus system for analyzing the adenovirus entry pathway has been developed that contains green fluorescent protein bound to the encapsidated viral DNA (AdLite viruses). AdLite viruses enter host cells and accumulate around the nuclei and near the microtubule organizing centers (MTOC). In live cells, individual AdLite particles were observed trafficking both toward and away from the nucleus. Depolymerization of microtubules during infection prevented AdLite accumulation around the MTOC; however, it did not abolish perinuclear localization of AdLite particles. Furthermore, depolymerization of microtubules did not affect AdLite motility and did not affect gene expression from wild-type adenovirus and adenovirus-derived vectors. These data revealed that adenovirus intracellular motility and nuclear targeting can be supported by a mechanism that does not rely on the microtubule network.
Collapse
Affiliation(s)
- J B Glotzer
- Institute for Molecular Pathology, 1030 Vienna, Austria
| | | | | | | | | |
Collapse
|
28
|
Furutani I, Watanabe Y, Prieto R, Masukawa M, Suzuki K, Naoi K, Thitamadee S, Shikanai T, Hashimoto T. The SPIRAL genes are required for directional control of cell elongation in Aarabidopsis thaliana. Development 2000; 127:4443-53. [PMID: 11003843 DOI: 10.1242/dev.127.20.4443] [Citation(s) in RCA: 154] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Cells at the elongation zone expand longitudinally to form the straight central axis of plant stems, hypocotyls and roots, and transverse cortical microtubule arrays are generally recognized to be important for the anisotropic growth. Recessive mutations in either of two Arabidopsis thaliana SPIRAL loci, SPR1 or SPR2, reduce anisotropic growth of endodermal and cortical cells in roots and etiolated hypocotyls, and induce right-handed helical growth in epidermal cell files of these organs. spr2 mutants additionally show right-handed twisting in petioles and petals. The spr1spr2 double mutant's phenotype is synergistic, suggesting that SPR1 and SPR2 act on a similar process but in separate pathways in controlling cell elongation. Interestingly, addition of a low dose of either of the microtubule-interacting drugs propyzamide or taxol in the agar medium was found to reduce anisotropic expansion of endodermal and cortical cells at the root elongation zone of wild-type seedlings, resulting in left-handed helical growth. In both spiral mutants, exogenous application of these drugs reverted the direction of the epidermal helix, in a dose-dependent manner, from right-handed to left-handed; propyzamide at 1 microM and taxol at 0.2-0.3 microM effectively suppressed the cell elongation defects of spiral seedlings. The spr1 phenotype is more pronounced at low temperatures and is nearly suppressed at high temperatures. Cortical microtubules in elongating epidermal cells of spr1 roots were arranged in left-handed helical arrays, whereas the highly isotropic cortical cells of etiolated spr1 hypocotyls showed microtubule arrays with irregular orientations. We propose that a microtubule-dependent process and SPR1/SPR2 act antagonistically to control directional cell elongation by preventing elongating cells from potential twisting. Our model may have implicit bearing on the circumnutation mechanism.
Collapse
Affiliation(s)
- I Furutani
- Graduate School of Biological Sciences, Nara Institute of Science and Technology, Takayama, Ikoma 630-0101, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
29
|
|
30
|
Abstract
The electron microscope was used to study the structure and three dimensional relationships of the components of the body cortex in thin sections of Paramecium multimicronucleatum. Micrographs of sections show that the cortex is covered externally by two closely apposed membranes (together approximately 250 A thick) constituting the pellicle. Beneath the pellicle the surface of the animal is molded into ridges that form a polygonal ridgework with depressed centers. It is these ridges that give the surface of the organism its characteristic configuration and correspond to the outer fibrillar system of the light microscope image. The outer ends of the trichocysts with their hood-shaped caps are located in the centers of the anterior and posterior ridges of each polygon. The cilia extend singly from the depressed centers of the surface polygons. Each cilium shows two axial filaments with 9 peripheral and parallel filaments embedded in a matrix and the whole surrouned by a thin ciliary membrane. The 9 peripheral filaments are double and these are evenly spaced in a circle around the central pair. The ciliary membrane is continuous with the outer member of the pellicular membrane, whereas the plasma membrane is continuous with the inner member of the pellicular membrane. At the level of the plasma membrane the proximal end of the cilium is continuous with its tube-shaped basal body or kinetosome. The peripheral filaments of the cilium, together with the material of cortical matrix which tends to condense around them, form the sheath of the basal body. The kinetodesma connecting the ciliary kinetosomes (inner fibrillar system of the light microscopist) is composed of a number of discrete fibrils which overlap in a shingle-like fashion. Each striated kinetosomal fibril originates from a ciliary kinetosome and runs parallel to other kinetosomal fibrils arising from posterior kinetosomes of a particular meridional array. Sections at the level of the ciliary kinetosomes reveal an additional fiber system, the infraciliary lattice system, which is separate and distinct from the kinetodesmal system. This system consists of a fibrous network of irregular polygons and runs roughly parallel to the surface of the animal. Mitochondria have a fine structure similar in general features to that described for a number of mammalian cell types, but different in certain details. The structures corresponding to cristae mitochondriales appear as finger-like projections or microvilli extending into the matrix of the organelle from the inner membrane of the paired mitochondrial membrane. The cortical cytoplasm contains also a particulate component and a system of vesicles respectively comparable to the nucleoprotein particles and to the endoplasmic reticulum described in various metazoan cell types. An accessory kinetosome has been observed in oblique sections of a number of non-dividing specimens slightly removed from the ciliary kinetosome and on the same meridional line as the cilia and trichocysts. Its position corresponds to the location of the kinetosome of the newly formed cilium in animals selected as being in the approaching fission stage of the life cycle.
Collapse
|