1
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Iqbal Lone W, Chand J, Kumar P, Garg Y, Ahmed Z, Mukherjee D, Goswami A, Momo H Anãl J. Discovery of colchicine aryne cycloadduct as a potent molecule for the abrogation of epithelial to mesenchymal transition via modulating cell cycle regulatory CDK-2 and CDK-4 kinases in breast cancer cells. Bioorg Chem 2024; 150:107581. [PMID: 38908129 DOI: 10.1016/j.bioorg.2024.107581] [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: 04/24/2024] [Revised: 05/30/2024] [Accepted: 06/19/2024] [Indexed: 06/24/2024]
Abstract
In this study, we synthesized a new-generation library of colchicine derivatives via cycloaddition of colchicine utilizing position C-8 and C-12 diene system regioselectivity with aryne precursor to generate a small, focused library of derivatives. We assessed their anticancer activity against various cancer cell lines like MCF-7, MDA-MB-231, MDA-MB-453, and PC-3. Normal human embryonic kidney cell line HEK-293 was used to determine the toxicity. Among these derivatives, silicon-tethered compound B-4a demonstrated the highest potency against breast cancer cells. Subsequent mechanistic studies revealed that B-4a effectively modulates cell cycle regulatory kinases (CDK-2 and CDK-4) and their associated cyclins (cyclin-B1, cyclin-D1), inducing apoptosis. Additionally, B-4a displayed a noteworthy impact on tubulin polymerization, compared to positive control flavopiridol hydrochloride in a dose-dependent manner, and significantly disrupted the vimentin cytoskeleton, contributing to G1 arrest in breast cancer cells. Moreover, B-4a exhibited substantial anti-metastatic properties by inhibiting breast cancer cell migration and invasion. These effects are attributed to the down-regulation of major epithelial to mesenchymal transition (EMT) factors, including vimentin and Twist-1, and the upregulation of the epithelial marker E-cadherin in an apoptosis-dependent manner.
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Affiliation(s)
- Waseem Iqbal Lone
- Natural Products and Medicinal Chemistry Division, CSIR- Indian Institute of Integrative Medicine, Jammu 180001, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Jagdish Chand
- Pharmacology Division, CSIR- Indian Institute of Integrative Medicine, Jammu 180001, India
| | - Puneet Kumar
- Natural Products and Medicinal Chemistry Division, CSIR- Indian Institute of Integrative Medicine, Jammu 180001, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Yashi Garg
- Pharmacology Division, CSIR- Indian Institute of Integrative Medicine, Jammu 180001, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Zabeer Ahmed
- Pharmacology Division, CSIR- Indian Institute of Integrative Medicine, Jammu 180001, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Debaraj Mukherjee
- Department of Chemical Sciences, Bose Institute, EN-80, Sector V, Kolkata 700091, WB, India
| | - Anindya Goswami
- Pharmacology Division, CSIR- Indian Institute of Integrative Medicine, Jammu 180001, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India.
| | - Jasha Momo H Anãl
- Natural Products and Medicinal Chemistry Division, CSIR- Indian Institute of Integrative Medicine, Jammu 180001, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India.
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2
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Shiff CE, Kondev J, Mohapatra L. Ultrasensitivity of microtubule severing due to damage repair. iScience 2024; 27:108874. [PMID: 38327774 PMCID: PMC10847648 DOI: 10.1016/j.isci.2024.108874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 01/01/2024] [Accepted: 01/08/2024] [Indexed: 02/09/2024] Open
Abstract
Microtubule-based cytoskeletal structures aid in cell motility, cell polarization, and intracellular transport. These functions require a coordinated effort of regulatory proteins which interact with microtubule cytoskeleton distinctively. In-vitro experiments have shown that free tubulin can repair nanoscale damages of microtubules created by severing proteins. Based on this observation, we theoretically analyze microtubule severing as a competition between the processes of damage spreading and tubulin-induced repair. We demonstrate that this model is in quantitative agreement with in-vitro experiments and predict the existence of a critical tubulin concentration above which severing becomes rare, fast, and sensitive to concentration of free tubulin. We show that this sensitivity leads to a dramatic increase in the dynamic range of steady-state microtubule lengths when the free tubulin concentration is varied, and microtubule lengths are controlled by severing. Our work demonstrates how synergy between tubulin and microtubule-associated proteins can bring about specific dynamical properties of microtubules.
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Affiliation(s)
- Chloe E. Shiff
- Institute for Computational and Mathematical Engineering, Stanford University, Stanford, CA 94305, USA
| | - Jane Kondev
- Department of Physics, Brandeis University, Waltham, MA 02454, USA
| | - Lishibanya Mohapatra
- School of Physics and Astronomy, College of Science, Rochester Institute of Technology, Rochester, NY 14623, USA
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3
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Campanacci V, Gigant B. The C-terminus of stathmin-like proteins governs the stability of their complexes with tubulin. Biochem Biophys Res Commun 2023; 682:244-249. [PMID: 37826947 DOI: 10.1016/j.bbrc.2023.10.023] [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: 10/05/2023] [Accepted: 10/05/2023] [Indexed: 10/14/2023]
Abstract
Microtubule dynamics is modulated by many cellular factors including stathmin family proteins. Vertebrate stathmins sequester two αβ-tubulin heterodimers into a tight complex that cannot be incorporated in microtubules. Stathmins are regulated at the expression level during development and among tissues; they are also regulated by phosphorylation. Here, we study the dissociation kinetics of tubulin:stathmin assemblies in presence of different tubulin-binding proteins and identify a critical role of the C-terminus of the stathmin partner. Destabilizing this C-terminal region may represent an additional regulatory mechanism of the interaction with tubulin of stathmin proteins.
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Affiliation(s)
- Valérie Campanacci
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France
| | - Benoît Gigant
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France.
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4
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Song X, Cui L, Wu M, Wang S, Song Y, Liu Z, Xue Z, Chen W, Zhang Y, Li H, Sun L, Liang X. DCX-EMAP is a core organizer for the ultrastructure of Drosophila mechanosensory organelles. J Cell Biol 2023; 222:e202209116. [PMID: 37651176 PMCID: PMC10471123 DOI: 10.1083/jcb.202209116] [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: 09/29/2022] [Revised: 06/21/2023] [Accepted: 08/09/2023] [Indexed: 09/01/2023] Open
Abstract
Mechanoreceptor cells develop specialized mechanosensory organelles (MOs), where force-sensitive channels and supporting structures are organized in an orderly manner to detect forces. It is intriguing how MOs are formed. Here, we address this issue by studying the MOs of fly ciliated mechanoreceptors. We show that the main structure of the MOs is a compound cytoskeleton formed of short microtubules and electron-dense materials (EDMs). In a knock-out mutant of DCX-EMAP, this cytoskeleton is nearly absent, suggesting that DCX-EMAP is required for the formation of the MOs and in turn fly mechanotransduction. Further analysis reveals that DCX-EMAP expresses in fly ciliated mechanoreceptors and localizes to the MOs. Moreover, it plays dual roles by promoting the assembly/stabilization of the microtubules and the accumulation of the EDMs in the MOs. Therefore, DCX-EMAP serves as a core ultrastructural organizer of the MOs, and this finding provides novel molecular insights as to how fly MOs are formed.
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Affiliation(s)
- Xuewei Song
- IDG/McGovern Institute for Brain Research, School of Life Sciences, Tsinghua University, Beijing, China
| | - Lihong Cui
- IDG/McGovern Institute for Brain Research, School of Life Sciences, Tsinghua University, Beijing, China
| | - Menghua Wu
- IDG/McGovern Institute for Brain Research, School of Life Sciences, Tsinghua University, Beijing, China
| | - Shan Wang
- IDG/McGovern Institute for Brain Research, School of Life Sciences, Tsinghua University, Beijing, China
| | - Yinlong Song
- IDG/McGovern Institute for Brain Research, School of Life Sciences, Tsinghua University, Beijing, China
| | - Zhen Liu
- IDG/McGovern Institute for Brain Research, School of Life Sciences, Tsinghua University, Beijing, China
| | - Zhaoyu Xue
- IDG/McGovern Institute for Brain Research, School of Life Sciences, Tsinghua University, Beijing, China
| | - Wei Chen
- IDG/McGovern Institute for Brain Research, School of Life Sciences, Tsinghua University, Beijing, China
| | - Yingjie Zhang
- IDG/McGovern Institute for Brain Research, School of Life Sciences, Tsinghua University, Beijing, China
| | - Hui Li
- IDG/McGovern Institute for Brain Research, School of Life Sciences, Tsinghua University, Beijing, China
| | - Landi Sun
- IDG/McGovern Institute for Brain Research, School of Life Sciences, Tsinghua University, Beijing, China
- Guangzhou Laboratory, Guangzhou, China
| | - Xin Liang
- IDG/McGovern Institute for Brain Research, School of Life Sciences, Tsinghua University, Beijing, China
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5
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Asega AF, Barros BCSC, Chaves AFA, Oliveira AK, Bertholim L, Kitano ES, Serrano SMT. Mouse skin peptidomic analysis of the hemorrhage induced by a snake venom metalloprotease. Amino Acids 2023; 55:1103-1119. [PMID: 37389729 DOI: 10.1007/s00726-023-03299-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Accepted: 06/22/2023] [Indexed: 07/01/2023]
Abstract
Hemorrhage induced by snake venom metalloproteases (SVMPs) results from proteolysis, capillary disruption, and blood extravasation. HF3, a potent SVMP of Bothrops jararaca, induces hemorrhage at pmol doses in the mouse skin. To gain insight into the hemorrhagic process, the main goal of this study was to analyze changes in the skin peptidome generated by injection of HF3, using approaches of mass spectrometry-based untargeted peptidomics. The results revealed that the sets of peptides found in the control and HF3-treated skin samples were distinct and derived from the cleavage of different proteins. Peptide bond cleavage site identification in the HF3-treated skin showed compatibility with trypsin-like serine proteases and cathepsins, suggesting the activation of host proteinases. Acetylated peptides, which originated from the cleavage at positions in the N-terminal region of proteins in both samples, were identified for the first time in the mouse skin peptidome. The number of peptides acetylated at the residue after the first Met residue, mostly Ser and Ala, was higher than that of peptides acetylated at the initial Met. Proteins cleaved in the hemorrhagic skin participate in cholesterol metabolism, PPAR signaling, and in the complement and coagulation cascades, indicating the impairment of these biological processes. The peptidomic analysis also indicated the emergence of peptides with potential biological activities, including pheromone, cell penetrating, quorum sensing, defense, and cell-cell communication in the mouse skin. Interestingly, peptides generated in the hemorrhagic skin promoted the inhibition of collagen-induced platelet aggregation and could act synergistically in the local tissue damage induced by HF3.
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Affiliation(s)
- Amanda F Asega
- Laboratory of Applied Toxinology, Center of Toxins, Immune-Response and Cell Signaling (CeTICS), Instituto Butantan, Av. Vital Brasil 1500, São Paulo, 05503-000, Brazil
| | - Bianca C S C Barros
- Laboratory of Applied Toxinology, Center of Toxins, Immune-Response and Cell Signaling (CeTICS), Instituto Butantan, Av. Vital Brasil 1500, São Paulo, 05503-000, Brazil
| | - Alison F A Chaves
- Laboratory of Applied Toxinology, Center of Toxins, Immune-Response and Cell Signaling (CeTICS), Instituto Butantan, Av. Vital Brasil 1500, São Paulo, 05503-000, Brazil
| | - Ana K Oliveira
- Laboratory of Applied Toxinology, Center of Toxins, Immune-Response and Cell Signaling (CeTICS), Instituto Butantan, Av. Vital Brasil 1500, São Paulo, 05503-000, Brazil
| | - Luciana Bertholim
- Laboratory of Applied Toxinology, Center of Toxins, Immune-Response and Cell Signaling (CeTICS), Instituto Butantan, Av. Vital Brasil 1500, São Paulo, 05503-000, Brazil
| | - Eduardo S Kitano
- Laboratory of Applied Toxinology, Center of Toxins, Immune-Response and Cell Signaling (CeTICS), Instituto Butantan, Av. Vital Brasil 1500, São Paulo, 05503-000, Brazil
| | - Solange M T Serrano
- Laboratory of Applied Toxinology, Center of Toxins, Immune-Response and Cell Signaling (CeTICS), Instituto Butantan, Av. Vital Brasil 1500, São Paulo, 05503-000, Brazil.
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6
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Velasco CD, Santarella-Mellwig R, Schorb M, Gao L, Thorn-Seshold O, Llobet A. Microtubule depolymerization contributes to spontaneous neurotransmitter release in vitro. Commun Biol 2023; 6:488. [PMID: 37147475 PMCID: PMC10163034 DOI: 10.1038/s42003-023-04779-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Accepted: 03/29/2023] [Indexed: 05/07/2023] Open
Abstract
Microtubules are key to multiple neuronal functions involving the transport of organelles, however, their relationship to neurotransmitter release is still unresolved. Here, we show that microtubules present in the presynaptic compartment of cholinergic autaptic synapses are dynamic. To investigate how the balance between microtubule growth and shrinkage affects neurotransmission we induced synchronous microtubule depolymerization by photoactivation of the chemical inhibitor SBTub3. The consequence was an increase in spontaneous neurotransmitter release. An analogous effect was obtained by dialyzing the cytosol with Kif18A, a plus-end-directed kinesin with microtubule depolymerizing activity. Kif18A also inhibited the refilling of the readily releasable pool of synaptic vesicles during high frequency stimulation. The action of Kif18A was associated to one order of magnitude increases in the numbers of exo-endocytic pits and endosomes present in the presynaptic terminal. An enhancement of spontaneous neurotransmitter release was also observed when neurons were dialyzed with stathmin-1, a protein with a widespread presence in the nervous system that induces microtubule depolymerization. Taken together, these results support that microtubules restrict spontaneous neurotransmitter release as well as promote the replenishment of the readily releasable pool of synaptic vesicles.
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Affiliation(s)
- Cecilia D Velasco
- Laboratory of Neurobiology, Department of Pathology and Experimental Therapy, Institute of Neurosciences, University of Barcelona, 08907, L'Hospitalet de Llobregat, Barcelona, Spain
- Bellvitge Biomedical Research Institute (IDIBELL), 08907, L'Hospitalet de Llobregat, Barcelona, Spain
| | - Rachel Santarella-Mellwig
- Electron Microscopy Core Facility, European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, 69117, Heidelberg, Germany
| | - Martin Schorb
- Electron Microscopy Core Facility, European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, 69117, Heidelberg, Germany
| | - Li Gao
- Department of Pharmacy, Ludwig-Maximilians University of Munich, Munich, 81377, Germany
| | - Oliver Thorn-Seshold
- Department of Pharmacy, Ludwig-Maximilians University of Munich, Munich, 81377, Germany
| | - Artur Llobet
- Laboratory of Neurobiology, Department of Pathology and Experimental Therapy, Institute of Neurosciences, University of Barcelona, 08907, L'Hospitalet de Llobregat, Barcelona, Spain.
- Bellvitge Biomedical Research Institute (IDIBELL), 08907, L'Hospitalet de Llobregat, Barcelona, Spain.
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7
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da Silva ES, Naghavi MH. Microtubules and viral infection. Adv Virus Res 2023; 115:87-134. [PMID: 37173066 DOI: 10.1016/bs.aivir.2023.02.003] [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] [Indexed: 04/05/2023]
Abstract
Microtubules (MTs) form rapidly adaptable, complex intracellular networks of filaments that not only provide structural support, but also form the tracks along which motors traffic macromolecular cargos to specific sub-cellular sites. These dynamic arrays play a central role in regulating various cellular processes including cell shape and motility as well as cell division and polarization. Given their complex organization and functional importance, MT arrays are carefully controlled by many highly specialized proteins that regulate the nucleation of MT filaments at distinct sites, their dynamic growth and stability, and their engagement with other subcellular structures and cargoes destined for transport. This review focuses on recent advances in our understanding of how MTs and their regulatory proteins function, including their active targeting and exploitation, during infection by viruses that utilize a wide variety of replication strategies that occur within different cellular sub-compartments or regions of the cell.
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Affiliation(s)
- Eveline Santos da Silva
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, IL, United States; HIV Clinical and Translational Research, Luxembourg Institute of Health, Department of Infection and Immunity, Esch-sur-Alzette, Luxembourg
| | - Mojgan H Naghavi
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, IL, United States.
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8
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Farmer VJ, Zanic M. Beyond the GTP-cap: Elucidating the molecular mechanisms of microtubule catastrophe. Bioessays 2023; 45:e2200081. [PMID: 36398561 PMCID: PMC10648283 DOI: 10.1002/bies.202200081] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 11/03/2022] [Accepted: 11/04/2022] [Indexed: 11/19/2022]
Abstract
Almost 40 years since the discovery of microtubule dynamic instability, the molecular mechanisms underlying microtubule dynamics remain an area of intense research interest. The "standard model" of microtubule dynamics implicates a "cap" of GTP-bound tubulin dimers at the growing microtubule end as the main determinant of microtubule stability. Loss of the GTP-cap leads to microtubule "catastrophe," a switch-like transition from microtubule growth to shrinkage. However, recent studies, using biochemical in vitro reconstitution, cryo-EM, and computational modeling approaches, challenge the simple GTP-cap model. Instead, a new perspective on the mechanisms of microtubule dynamics is emerging. In this view, highly dynamic transitions between different structural conformations of the growing microtubule end - which may or may not be directly linked to the nucleotide content at the microtubule end - ultimately drive microtubule catastrophe.
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Affiliation(s)
- Veronica J. Farmer
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee, USA
| | - Marija Zanic
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee, USA
- Department of Biomolecular and Chemical Engineering, Department of Biochemistry, Vanderbilt University, Nashville, Tennessee, USA
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9
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Nielsen AW, Sari L, Fraser R, Lin MM. Protein aggregates thermodynamically order regardless of sequence. Proteins 2022; 91:705-711. [PMID: 36576407 DOI: 10.1002/prot.26460] [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: 09/24/2022] [Revised: 11/23/2022] [Accepted: 12/22/2022] [Indexed: 12/29/2022]
Abstract
Proteins can aggregate into disordered aggregates or ordered assemblies such as amyloid fibrils. These two distinct phases serve differing roles in function and disease. How protein sequence determines the preferred phase is unknown. Here we establish a statistical mechanical disorder-to-order transition condition for compact polymer aggregates, including proteins. The theory produces a simple universal equation determining the favored phase as a function of temperature, polymer length, and interaction energy variance. We show that the sequence-dependent energy variance is efficiently calculated using atomistic simulations, so that the theory has no adjustable parameters. The equation accurately predicts experimental length-dependent crystallization temperatures of synthetic polymers. The equation also predicts that all protein sequences that aggregate will also favor ordering. Consequently, energy must be expended to maintain the steady-state disordered phase if it is not kinetically metastable on physiological timescales. More broadly, the theory suggests that aggregates of organic polymers will generally tend to order on habitable planets.
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Affiliation(s)
- Aleksandra W Nielsen
- Green Center for Systems Biology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Levent Sari
- Green Center for Systems Biology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Rowan Fraser
- Green Center for Systems Biology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Milo M Lin
- Green Center for Systems Biology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
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10
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Guyomar C, Bousquet C, Ku S, Heumann JM, Guilloux G, Gaillard N, Heichette C, Duchesne L, Steinmetz MO, Gibeaux R, Chrétien D. Changes in seam number and location induce holes within microtubules assembled from porcine brain tubulin and in Xenopus egg cytoplasmic extracts. eLife 2022; 11:e83021. [PMID: 36503602 PMCID: PMC9788831 DOI: 10.7554/elife.83021] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 12/09/2022] [Indexed: 12/15/2022] Open
Abstract
Microtubules are tubes of about 25 nm in diameter that are critically involved in a variety of cellular functions, including motility, compartmentalization, and division. They are considered as pseudo-helical polymers whose constituent αβ-tubulin heterodimers share lateral homotypic interactions, except at one unique region called the seam. Here, we used a segmented sub-tomogram averaging strategy to reassess this paradigm and analyze the organization of the αβ-tubulin heterodimers in microtubules assembled from purified porcine brain tubulin in the presence of GTP and GMPCPP, and in Xenopus egg cytoplasmic extracts. We find that in almost all conditions, microtubules incorporate variable protofilament and/or tubulin subunit helical-start numbers, as well as variable numbers of seams. Strikingly, the seam number and location vary along individual microtubules, generating holes of one to a few subunits in size within their lattices. Together, our results reveal that the formation of mixed and discontinuous microtubule lattices is an intrinsic property of tubulin that requires the formation of unique lateral interactions without longitudinal ones. They further suggest that microtubule assembly is tightly regulated in a cytoplasmic environment.
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Affiliation(s)
- Charlotte Guyomar
- Univ Rennes, CNRS, IGDR (Institut de Génétique et Développement de Rennes) - UMR 6290, F-35000RennesFrance
| | - Clément Bousquet
- Univ Rennes, CNRS, IGDR (Institut de Génétique et Développement de Rennes) - UMR 6290, F-35000RennesFrance
| | - Siou Ku
- Univ Rennes, CNRS, IGDR (Institut de Génétique et Développement de Rennes) - UMR 6290, F-35000RennesFrance
| | - John M Heumann
- Department of Molecular, Cellular and Developmental Biology, University of Colorado BoulderBoulderUnited States
| | - Gabriel Guilloux
- Univ Rennes, CNRS, IGDR (Institut de Génétique et Développement de Rennes) - UMR 6290, F-35000RennesFrance
| | - Natacha Gaillard
- Laboratory of Biomolecular Research, Division of Biology and Chemistry, Paul Scherrer InstituteVilligenSwitzerland
| | - Claire Heichette
- Univ Rennes, CNRS, IGDR (Institut de Génétique et Développement de Rennes) - UMR 6290, F-35000RennesFrance
| | - Laurence Duchesne
- Univ Rennes, CNRS, IGDR (Institut de Génétique et Développement de Rennes) - UMR 6290, F-35000RennesFrance
| | - Michel O Steinmetz
- Laboratory of Biomolecular Research, Division of Biology and Chemistry, Paul Scherrer InstituteVilligenSwitzerland
- University of Basel, BiozentrumBaselSwitzerland
| | - Romain Gibeaux
- Univ Rennes, CNRS, IGDR (Institut de Génétique et Développement de Rennes) - UMR 6290, F-35000RennesFrance
| | - Denis Chrétien
- Univ Rennes, CNRS, IGDR (Institut de Génétique et Développement de Rennes) - UMR 6290, F-35000RennesFrance
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11
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Wattanathamsan O, Pongrakhananon V. Emerging role of microtubule-associated proteins on cancer metastasis. Front Pharmacol 2022; 13:935493. [PMID: 36188577 PMCID: PMC9515585 DOI: 10.3389/fphar.2022.935493] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 08/29/2022] [Indexed: 12/29/2022] Open
Abstract
The major cause of death in cancer patients is strongly associated with metastasis. While much remains to be understood, microtubule-associated proteins (MAPs) have shed light on metastatic progression’s molecular mechanisms. In this review article, we focus on the role of MAPs in cancer aggressiveness, particularly cancer metastasis activity. Increasing evidence has shown that a growing number of MAP member proteins might be fundamental regulators involved in altering microtubule dynamics, contributing to cancer migration, invasion, and epithelial-to-mesenchymal transition. MAP types have been established according to their microtubule-binding site and function in microtubule-dependent activities. We highlight that altered MAP expression was commonly found in many cancer types and related to cancer progression based on available evidence. Furthermore, we discuss and integrate the relevance of MAPs and related molecular signaling pathways in cancer metastasis. Our review provides a comprehensive understanding of MAP function on microtubules. It elucidates how MAPs regulate cancer progression, preferentially in metastasis, providing substantial scientific information on MAPs as potential therapeutic targets and prognostic markers for cancer management.
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Affiliation(s)
- Onsurang Wattanathamsan
- Preclinical Toxicity and Efficacy Assessment of Medicines and Chemicals Research Unit, Chulalongkorn University, Bangkok, Thailand
- Department of Pharmacology and Physiology, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, Thailand
| | - Varisa Pongrakhananon
- Preclinical Toxicity and Efficacy Assessment of Medicines and Chemicals Research Unit, Chulalongkorn University, Bangkok, Thailand
- Department of Pharmacology and Physiology, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, Thailand
- *Correspondence: Varisa Pongrakhananon,
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12
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Effects of length-dependent positive feedback on length distributions of microtubules undergoing hydrolysis. J Biosci 2022. [DOI: 10.1007/s12038-022-00255-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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13
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Liao M, Kuo YW, Howard J. Counting fluorescently labeled proteins in tissues in the spinning disk microscope using single-molecule calibrations. Mol Biol Cell 2022; 33:ar48. [PMID: 35323029 PMCID: PMC9265152 DOI: 10.1091/mbc.e21-12-0618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Quantification of molecular numbers and concentrations in living cells is critical for testing models of complex biological phenomena. Counting molecules in cells requires estimation of the fluorescence intensity of single molecules, which is generally limited to imaging near cell surfaces, in isolated cells, or where motions are diffusive. To circumvent this difficulty, we have devised a calibration technique for spinning–disk confocal microscopy, commonly used for imaging in tissues, that uses single–step bleaching kinetics to estimate the single–fluorophore intensity. To cross–check our calibrations, we compared the brightness of fluorophores in the SDC microscope to those in the total internal reflection and epifluorescence microscopes. We applied this calibration method to quantify the number of end–binding protein 1 (EB1)–eGFP in the comets of growing microtubule ends and to measure the cytoplasmic concentration of EB1–eGFP in sensory neurons in fly larvae. These measurements allowed us to estimate the dissociation constant of EB1–eGFP from the microtubules as well as the GTP–tubulin cap size. Our results show the unexplored potential of single–molecule imaging using spinning–disk confocal microscopy and provide a straightforward method to count the absolute number of fluorophores in tissues that can be applied to a wide range of biological systems and imaging techniques.
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Affiliation(s)
- Maijia Liao
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, USA
| | - Yin-Wei Kuo
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, USA
| | - Jonathon Howard
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, USA
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14
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Zheng R, Du Y, Wang X, Liao T, Zhang Z, Wang N, Li X, Shen Y, Shi L, Luo J, Xia J, Wang Z, Xu J. KIF2C regulates synaptic plasticity and cognition in mice through dynamic microtubule depolymerization. eLife 2022; 11:72483. [PMID: 35138249 PMCID: PMC8828051 DOI: 10.7554/elife.72483] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 02/01/2022] [Indexed: 11/13/2022] Open
Abstract
Dynamic microtubules play a critical role in cell structure and function. In nervous system, microtubules are the major route for cargo protein trafficking and they specially extend into and out of synapses to regulate synaptic development and plasticity. However, the detailed depolymerization mechanism that regulates dynamic microtubules in synapses and dendrites is still unclear. In this study, we find that KIF2C, a dynamic microtubule depolymerization protein without known function in the nervous system, plays a pivotal role in the structural and functional plasticity of synapses and regulates cognitive function in mice. Through its microtubule depolymerization capability, KIF2C regulates microtubule dynamics in dendrites, and regulates microtubule invasion of spines in neurons in a neuronal activity-dependent manner. Using RNAi knockdown and conditional knockout approaches, we showed that KIF2C regulates spine morphology and synaptic membrane expression of AMPA receptors. Moreover, KIF2C deficiency leads to impaired excitatory transmission, long-term potentiation, and altered cognitive behaviors in mice. Collectively, our study explores a novel function of KIF2C in the nervous system and provides an important regulatory mechanism on how activity-dependent microtubule dynamic regulates synaptic plasticity and cognition behaviors.
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Affiliation(s)
- Rui Zheng
- Department of Neurobiology and Department of Rehabilitation of the Children's Hospital, Zhejiang University School of Medicine, Hangzhou, China.,NHC and CAMS Key Laboratory of Medical Neurobiology, Ministry of Education Frontier Science Center for Brain Research and Brain Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
| | - Yonglan Du
- Department of Neurobiology and Department of Rehabilitation of the Children's Hospital, Zhejiang University School of Medicine, Hangzhou, China.,NHC and CAMS Key Laboratory of Medical Neurobiology, Ministry of Education Frontier Science Center for Brain Research and Brain Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
| | - Xintai Wang
- NHC and CAMS Key Laboratory of Medical Neurobiology, Ministry of Education Frontier Science Center for Brain Research and Brain Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
| | - Tailin Liao
- Department of Neurobiology and Department of Rehabilitation of the Children's Hospital, Zhejiang University School of Medicine, Hangzhou, China.,NHC and CAMS Key Laboratory of Medical Neurobiology, Ministry of Education Frontier Science Center for Brain Research and Brain Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
| | - Zhe Zhang
- Department of Neurobiology and Department of Rehabilitation of the Children's Hospital, Zhejiang University School of Medicine, Hangzhou, China.,NHC and CAMS Key Laboratory of Medical Neurobiology, Ministry of Education Frontier Science Center for Brain Research and Brain Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
| | - Na Wang
- Department of Neurobiology and Department of Rehabilitation of the Children's Hospital, Zhejiang University School of Medicine, Hangzhou, China.,NHC and CAMS Key Laboratory of Medical Neurobiology, Ministry of Education Frontier Science Center for Brain Research and Brain Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
| | - Xiumao Li
- Department of Orthopedic Surgery, the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Ying Shen
- Department of Physiology and Department of Neurology of First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Lei Shi
- JNU-HKUST Joint Laboratory for Neuroscience and Innovative Drug Research, Jinan University, Guanzhou, China
| | - Jianhong Luo
- Department of Neurobiology and Department of Rehabilitation of the Children's Hospital, Zhejiang University School of Medicine, Hangzhou, China.,NHC and CAMS Key Laboratory of Medical Neurobiology, Ministry of Education Frontier Science Center for Brain Research and Brain Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
| | - Jun Xia
- Division of Life Science and The Brain and Intelligence Research Institute, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Ziyi Wang
- Innovative Institute of Basic Medical Sciences of Zhejiang University (Yuhang), Hangzhou, China
| | - Junyu Xu
- Department of Neurobiology and Department of Rehabilitation of the Children's Hospital, Zhejiang University School of Medicine, Hangzhou, China.,NHC and CAMS Key Laboratory of Medical Neurobiology, Ministry of Education Frontier Science Center for Brain Research and Brain Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
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15
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Jijumon AS, Bodakuntla S, Genova M, Bangera M, Sackett V, Besse L, Maksut F, Henriot V, Magiera MM, Sirajuddin M, Janke C. Lysate-based pipeline to characterize microtubule-associated proteins uncovers unique microtubule behaviours. Nat Cell Biol 2022; 24:253-267. [PMID: 35102268 DOI: 10.1038/s41556-021-00825-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 11/23/2021] [Indexed: 12/22/2022]
Abstract
The microtubule cytoskeleton forms complex macromolecular assemblies with a range of microtubule-associated proteins (MAPs) that have fundamental roles in cell architecture, division and motility. Determining how an individual MAP modulates microtubule behaviour is an important step in understanding the physiological roles of various microtubule assemblies. To characterize how MAPs control microtubule properties and functions, we developed an approach allowing for medium-throughput analyses of MAPs in cell-free conditions using lysates of mammalian cells. Our pipeline allows for quantitative as well as ultrastructural analyses of microtubule-MAP assemblies. Analysing 45 bona fide and potential mammalian MAPs, we uncovered previously unknown activities that lead to distinct and unique microtubule behaviours such as microtubule coiling or hook formation, or liquid-liquid phase separation along the microtubule lattice that initiates microtubule branching. We have thus established a powerful tool for a thorough characterization of a wide range of MAPs and MAP variants, thus opening avenues for the determination of mechanisms underlying their physiological roles and pathological implications.
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Affiliation(s)
- A S Jijumon
- Institut Curie, Université PSL, CNRS UMR3348, Orsay, France
- Université Paris-Saclay, CNRS UMR3348, Orsay, France
| | - Satish Bodakuntla
- Institut Curie, Université PSL, CNRS UMR3348, Orsay, France
- Université Paris-Saclay, CNRS UMR3348, Orsay, France
| | - Mariya Genova
- Institut Curie, Université PSL, CNRS UMR3348, Orsay, France
- Université Paris-Saclay, CNRS UMR3348, Orsay, France
| | - Mamata Bangera
- Institute for Stem Cell Science and Regenerative Medicine (inStem), Bangalore, India
| | - Violet Sackett
- Institut Curie, Université PSL, CNRS UMR3348, Orsay, France
- Université Paris-Saclay, CNRS UMR3348, Orsay, France
- Department of Ecology and Evolutionary Biology, Brown University, Providence, RI, USA
| | - Laetitia Besse
- Institut Curie, Université Paris-Saclay, Centre d'Imagerie Multimodale INSERM US43, CNRS UMS2016, Orsay, France
| | - Fatlinda Maksut
- Institut Curie, Université PSL, CNRS UMR3348, Orsay, France
- Université Paris-Saclay, CNRS UMR3348, Orsay, France
| | - Veronique Henriot
- Institut Curie, Université PSL, CNRS UMR3348, Orsay, France
- Université Paris-Saclay, CNRS UMR3348, Orsay, France
| | - Maria M Magiera
- Institut Curie, Université PSL, CNRS UMR3348, Orsay, France
- Université Paris-Saclay, CNRS UMR3348, Orsay, France
| | | | - Carsten Janke
- Institut Curie, Université PSL, CNRS UMR3348, Orsay, France.
- Université Paris-Saclay, CNRS UMR3348, Orsay, France.
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16
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Effects of random hydrolysis on biofilament length distributions in a shared subunit pool. Biophys J 2022; 121:502-514. [PMID: 34954156 PMCID: PMC8822617 DOI: 10.1016/j.bpj.2021.12.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2020] [Revised: 08/15/2021] [Accepted: 12/20/2021] [Indexed: 02/03/2023] Open
Abstract
The sizes of filamentous structures in a cell are often regulated for many physiological processes. A key question in cell biology is how such size control is achieved. Here, we theoretically study the length distributions of multiple filaments, growing by stochastic assembly and disassembly of subunits from a limiting subunit pool. Importantly, we consider a chemical switching of subunits (hydrolysis) prevalent in many biofilaments like microtubules (MTs). We show by simulations of different models that hydrolysis leads to a skewed unimodal length distribution for a single MT. In contrast, hydrolysis can lead to bimodal distributions of individual lengths for two MTs, where individual filaments toggle stochastically between bigger and smaller sizes. For more than two MTs, length distributions are also bimodal, although the bimodality becomes less prominent. We further show that this collective phenomenon is connected with the nonequilibrium nature of hydrolysis, and the bimodality disappears for reversible dynamics. Consistent with earlier theoretical studies, a homogeneous subunit pool, without hydrolysis, cannot control filament lengths. We thus elucidate the role of hydrolysis as a control mechanism on MT length diversity.
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17
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Gaillard J, Blanchoin L, Théry M, Schaedel L. Visualization and Quantification of Microtubule Self-Repair. Methods Mol Biol 2022; 2430:279-289. [PMID: 35476339 DOI: 10.1007/978-1-0716-1983-4_18] [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] [Indexed: 06/14/2023]
Abstract
Since its discovery, several decades ago, microtubule dynamic instability has been the subject of countless studies that demonstrate its impact on cellular behavior in health and disease. Recent studies reveal a new dimension of microtubule dynamics. Microtubules are not only dynamic at their tips but also exhibit loss and incorporation of tubulin subunits along their lattice far from the tips. Although this phenomenon has been observed to occur under various conditions in vitro as well as in cells, many questions remain regarding the regulation of lattice dynamics and their contribution to overall microtubule network organization and function. Compared to microtubule tip dynamics, the dynamics of tubulin incorporation along the lattice are more challenging to investigate as they are hidden in classical experimental setups, which is likely the reason they were overlooked for a long time. In this chapter, we present a strategy to visualize and quantify the incorporation of tubulin subunits into the microtubule lattice in vitro. The proposed method does not require specialized equipment and can thus be carried out readily in most research laboratories.
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Affiliation(s)
- Jérémie Gaillard
- Univ. Grenoble-Alpes, CEA, CNRS, INRA, Biosciences & Biotechnology Institute of Grenoble, Laboratoire de Phyiologie Cellulaire & Végétale, CytoMorpho Lab, Grenoble, France
| | - Laurent Blanchoin
- Univ. Grenoble-Alpes, CEA, CNRS, INRA, Biosciences & Biotechnology Institute of Grenoble, Laboratoire de Phyiologie Cellulaire & Végétale, CytoMorpho Lab, Grenoble, France
- Univ. Paris Diderot, INSERM, CEA, Hôpital Saint Louis, Institut Universitaire d'Hematologie, UMRS1160, CytoMorpho Lab, Paris, France
| | - Manuel Théry
- Univ. Grenoble-Alpes, CEA, CNRS, INRA, Biosciences & Biotechnology Institute of Grenoble, Laboratoire de Phyiologie Cellulaire & Végétale, CytoMorpho Lab, Grenoble, France
- Univ. Paris Diderot, INSERM, CEA, Hôpital Saint Louis, Institut Universitaire d'Hematologie, UMRS1160, CytoMorpho Lab, Paris, France
| | - Laura Schaedel
- Faculty of Natural Sciences and Technology, Saarland University, Saarbrücken, Germany.
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18
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Zhao X, Zhang R, Yu X, Yu N, Shi Y, Shu M, Shen Y. Discovery of Novel Tubulin Polymerization Inhibitors by Utilizing 3D-QSAR, Molecular Docking and Molecular Dynamics Simulation. NEW J CHEM 2022. [DOI: 10.1039/d2nj02773a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Tubulin is a potential therapeutic target for cancer. Compounds inhibit the polymerization of tubulin or promote the polymerization of tubulin to interfere with the mitotic process of cells, resulting in...
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19
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Desmin intermediate filaments and tubulin detyrosination stabilize growing microtubules in the cardiomyocyte. Basic Res Cardiol 2022; 117:53. [PMID: 36326891 PMCID: PMC9633452 DOI: 10.1007/s00395-022-00962-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 09/26/2022] [Accepted: 10/17/2022] [Indexed: 11/06/2022]
Abstract
In heart failure, an increased abundance of post-translationally detyrosinated microtubules stiffens the cardiomyocyte and impedes its contractile function. Detyrosination promotes interactions between microtubules, desmin intermediate filaments, and the sarcomere to increase cytoskeletal stiffness, yet the mechanism by which this occurs is unknown. We hypothesized that detyrosination may regulate the growth and shrinkage of dynamic microtubules to facilitate interactions with desmin and the sarcomere. Through a combination of biochemical assays and direct observation of growing microtubule plus-ends in adult cardiomyocytes, we find that desmin is required to stabilize growing microtubules at the level of the sarcomere Z-disk, where desmin also rescues shrinking microtubules from continued depolymerization. Further, reducing detyrosination (i.e. tyrosination) below basal levels promotes frequent depolymerization and less efficient growth of microtubules. This is concomitant with tyrosination promoting the interaction of microtubules with the depolymerizing protein complex of end-binding protein 1 (EB1) and CAP-Gly domain-containing linker protein 1 (CLIP1/CLIP170). The dynamic growth and shrinkage of tyrosinated microtubules reduce their opportunity for stabilizing interactions at the Z-disk region, coincident with tyrosination globally reducing microtubule stability. These data provide a model for how intermediate filaments and tubulin detyrosination establish long-lived and physically reinforced microtubules that stiffen the cardiomyocyte and inform both the mechanism of action and therapeutic index for strategies aimed at restoring tyrosination for the treatment of cardiac disease.
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20
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Martinez D, Zhu M, Guidry JJ, Majeste N, Mao H, Yanofsky ST, Tian X, Wu C. Mask, the Drosophila ankyrin repeat and KH domain-containing protein, affects microtubule stability. J Cell Sci 2021; 134:272264. [PMID: 34553767 PMCID: PMC8572007 DOI: 10.1242/jcs.258512] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Accepted: 09/16/2021] [Indexed: 11/26/2022] Open
Abstract
Proper regulation of microtubule (MT) stability and dynamics is vital for essential cellular processes, including axonal transportation and synaptic growth and remodeling in neurons. In the present study, we demonstrate that the Drosophila ankyrin repeat and KH domain-containing protein Mask negatively affects MT stability in both larval muscles and motor neurons. In larval muscles, loss-of-function of mask increases MT polymer length, and in motor neurons, loss of mask function results in overexpansion of the presynaptic terminal at the larval neuromuscular junctions (NMJs). mask genetically interacts with stathmin (stai), a neuronal modulator of MT stability, in the regulation of axon transportation and synaptic terminal stability. Our structure–function analysis of Mask revealed that its ankyrin repeats domain-containing N-terminal portion is sufficient to mediate Mask's impact on MT stability. Furthermore, we discovered that Mask negatively regulates the abundance of the MT-associated protein Jupiter in motor neuron axons, and that neuronal knocking down of Jupiter partially suppresses mask loss-of-function phenotypes at the larval NMJs. Taken together, our studies demonstrate that Mask is a novel regulator for MT stability, and such a role of Mask requires normal function of Jupiter. Summary: Mask is a novel regulator of MT stability in Drosophila. Mask shows prominent interplay with two important modulators of MT, Tau and Stathmin (Stai), whose mutations are related to human diseases.
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Affiliation(s)
- Daniel Martinez
- Neuroscience Center of Excellence, Department of Cell Biology and Anatomy, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA
| | - Mingwei Zhu
- Neuroscience Center of Excellence, Department of Cell Biology and Anatomy, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA
| | - Jessie J Guidry
- Proteomics Core Facility, and the Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA
| | - Niles Majeste
- Neuroscience Center of Excellence, Department of Cell Biology and Anatomy, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA
| | - Hui Mao
- Neuroscience Center of Excellence, Department of Cell Biology and Anatomy, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA
| | - Sarah T Yanofsky
- Neuroscience Center of Excellence, Department of Cell Biology and Anatomy, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA
| | - Xiaolin Tian
- Neuroscience Center of Excellence, Department of Cell Biology and Anatomy, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA
| | - Chunlai Wu
- Neuroscience Center of Excellence, Department of Cell Biology and Anatomy, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA
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21
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Abstract
Microtubules are dynamic cytoskeletal filaments composed of αβ-tubulin heterodimers. Historically, the dynamics of single tubulin interactions at the growing microtubule tip have been inferred from steady-state growth kinetics. However, recent advances in the production of recombinant tubulin and in high-resolution optical and cryo-electron microscopies have opened new windows into understanding the impacts of specific intermolecular interactions during growth. The microtubule lattice is held together by lateral and longitudinal tubulin-tubulin interactions, and these interactions are in turn regulated by the GTP hydrolysis state of the tubulin heterodimer. Furthermore, tubulin can exist in either an extended or a compacted state in the lattice. Growing evidence has led to the suggestion that binding of microtubule-associated proteins (MAPs) or motors can induce changes in tubulin conformation and that this information can be communicated through the microtubule lattice. Progress in understanding how dynamic tubulin-tubulin interactions control dynamic instability has benefitted from visualizing structures of growing microtubule plus ends and through stochastic biochemical models constrained by experimental data. Here, we review recent insights into the molecular basis of microtubule growth and discuss how MAPs and regulatory proteins alter tubulin-tubulin interactions to exert their effects on microtubule growth and stability.
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Affiliation(s)
- Joseph M Cleary
- Department of Biomedical Engineering, Pennsylvania State University, University Park, PA 16802, USA
| | - William O Hancock
- Department of Biomedical Engineering, Pennsylvania State University, University Park, PA 16802, USA.
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22
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Spindle scaling mechanisms. Essays Biochem 2021; 64:383-396. [PMID: 32501481 DOI: 10.1042/ebc20190064] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 05/11/2020] [Accepted: 05/12/2020] [Indexed: 02/02/2023]
Abstract
The mitotic spindle robustly scales with cell size in a plethora of different organisms. During development and throughout evolution, the spindle adjusts to cell size in metazoans and yeast in order to ensure faithful chromosome separation. Spindle adjustment to cell size occurs by the scaling of spindle length, spindle shape and the velocity of spindle assembly and elongation. Different mechanisms, depending on spindle structure and organism, account for these scaling relationships. The limited availability of critical spindle components, protein gradients, sequestration of spindle components, or post-translational modification and differential expression levels have been implicated in the regulation of spindle length and the spindle assembly/elongation velocity in a cell size-dependent manner. In this review, we will discuss the phenomenon and mechanisms of spindle length, spindle shape and spindle elongation velocity scaling with cell size.
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23
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Kuo YW, Howard J. Cutting, Amplifying, and Aligning Microtubules with Severing Enzymes. Trends Cell Biol 2020; 31:50-61. [PMID: 33183955 PMCID: PMC7749064 DOI: 10.1016/j.tcb.2020.10.004] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 10/12/2020] [Accepted: 10/15/2020] [Indexed: 02/08/2023]
Abstract
Microtubule-severing enzymes - katanin, spastin, fidgetin - are related AAA-ATPases that cut microtubules into shorter filaments. These proteins, also called severases, are involved in a wide range of cellular processes including cell division, neuronal development, and tissue morphogenesis. Paradoxically, severases can amplify the microtubule cytoskeleton and not just destroy it. Recent work on spastin and katanin has partially resolved this paradox by showing that these enzymes are strong promoters of microtubule growth. Here, we review recent structural and biophysical advances in understanding the molecular mechanisms of severing and growth promotion that provide insight into how severing enzymes shape microtubule networks.
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Affiliation(s)
- Yin-Wei Kuo
- Department of Chemistry, Yale University, New Haven, CT 06511, USA; Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA
| | - Jonathon Howard
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA.
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24
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Gallo G. The bioenergetics of neuronal morphogenesis and regeneration: Frontiers beyond the mitochondrion. Dev Neurobiol 2020; 80:263-276. [PMID: 32750228 DOI: 10.1002/dneu.22776] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 07/29/2020] [Accepted: 07/29/2020] [Indexed: 12/27/2022]
Abstract
The formation of axons and dendrites during development, and their regeneration following injury, are energy intensive processes. The underlying assembly and dynamics of the cytoskeleton, axonal transport mechanisms, and extensive signaling networks all rely on ATP and GTP consumption. Cellular ATP is generated through oxidative phosphorylation (OxP) in mitochondria, glycolysis and "regenerative" kinase systems. Recent investigations have focused on the role of the mitochondrion in axonal development and regeneration emphasizing the importance of this organelle and OxP in axon development and regeneration. In contrast, the understanding of alternative sources of ATP in neuronal morphogenesis and regeneration remains largely unexplored. This review focuses on the current state of the field of neuronal bioenergetics underlying morphogenesis and regeneration and considers the literature on the bioenergetics of non-neuronal cell motility to emphasize the potential contributions of non-mitochondrial energy sources.
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Affiliation(s)
- Gianluca Gallo
- Department of Anatomy and Cell Biology, Lewis Katz School of Medicine, Shriners Hospitals Pediatric Research Center, Temple University, Philadelphia, PA, USA
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25
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Regulation of invadosomes by microtubules: Not only a matter of railways. Eur J Cell Biol 2020; 99:151109. [DOI: 10.1016/j.ejcb.2020.151109] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 07/02/2020] [Accepted: 07/13/2020] [Indexed: 12/19/2022] Open
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26
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Nosala C, Hagen KD, Hilton N, Chase TM, Jones K, Loudermilk R, Nguyen K, Dawson SC. Disc-associated proteins mediate the unusual hyperstability of the ventral disc in Giardia lamblia. J Cell Sci 2020; 133:jcs.227355. [PMID: 32661087 DOI: 10.1242/jcs.227355] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 06/29/2020] [Indexed: 12/26/2022] Open
Abstract
Giardia lamblia, a widespread parasitic protozoan, attaches to the host gastrointestinal epithelium by using the ventral disc, a complex microtubule (MT) organelle. The 'cup-like' disc is formed by a spiral MT array that scaffolds numerous disc-associated proteins (DAPs) and higher-order protein complexes. In interphase, the disc is hyperstable and has limited MT dynamics; however, it remains unclear how DAPs confer these properties. To investigate mechanisms of hyperstability, we confirmed the disc-specific localization of over 50 new DAPs identified by using both a disc proteome and an ongoing GFP localization screen. DAPs localize to specific disc regions and many lack similarity to known proteins. By screening 14 CRISPRi-mediated DAP knockdown (KD) strains for defects in hyperstability and MT dynamics, we identified two strains - DAP5188KD and DAP6751KD -with discs that dissociate following high-salt fractionation. Discs in the DAP5188KD strain were also sensitive to treatment with the MT-polymerization inhibitor nocodazole. Thus, we confirm here that at least two of the 87 known DAPs confer hyperstable properties to the disc MTs, and we anticipate that other DAPs contribute to disc MT stability, nucleation and assembly.
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Affiliation(s)
- Christopher Nosala
- Department of Microbiology and Molecular Genetics, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA
| | - Kari D Hagen
- Department of Microbiology and Molecular Genetics, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA
| | - Nicholas Hilton
- Department of Microbiology and Molecular Genetics, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA
| | - Tiffany M Chase
- Department of Microbiology and Molecular Genetics, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA
| | - Kelci Jones
- Department of Microbiology and Molecular Genetics, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA
| | - Rita Loudermilk
- Department of Microbiology and Molecular Genetics, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA
| | - Kristofer Nguyen
- Department of Microbiology and Molecular Genetics, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA
| | - Scott C Dawson
- Department of Microbiology and Molecular Genetics, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA
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27
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Lin Y, Wei YL, She ZY. Kinesin-8 motors: regulation of microtubule dynamics and chromosome movements. Chromosoma 2020; 129:99-110. [PMID: 32417983 DOI: 10.1007/s00412-020-00736-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Revised: 05/06/2020] [Accepted: 05/07/2020] [Indexed: 02/01/2023]
Abstract
Microtubules are essential for intracellular transport, cell motility, spindle assembly, and chromosome segregation during cell division. Microtubule dynamics regulate the proper spindle organization and thus contribute to chromosome congression and segregation. Accumulating studies suggest that kinesin-8 motors are emerging regulators of microtubule dynamics and organizations. In this review, we provide an overview of the studies focused on kinesin-8 motors in cell division. We discuss the structures and molecular kinetics of kinesin-8 motors. We highlight the essential roles and mechanisms of kinesin-8 in the regulation of microtubule dynamics and spindle organization. We also shed light on the functions of kinesin-8 motors in chromosome movement and the spindle assembly checkpoint during the cell cycle.
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Affiliation(s)
- Yang Lin
- Department of Cell Biology and Genetics, The School of Basic Medical Sciences, Fujian Medical University, Fuzhou, 350122, Fujian, China.,Key Laboratory of Stem Cell Engineering and Regenerative Medicine, Fujian Province University, Fuzhou, 350122, Fujian, China
| | - Ya-Lan Wei
- Fujian Obstetrics and Gynecology Hospital, Fuzhou, 350011, Fujian, China.,Medical Research Center, Fujian Maternity and Child Health Hospital, Affiliated Hospital of Fujian Medical University, Fuzhou, 350001, Fujian, China
| | - Zhen-Yu She
- Department of Cell Biology and Genetics, The School of Basic Medical Sciences, Fujian Medical University, Fuzhou, 350122, Fujian, China. .,Key Laboratory of Stem Cell Engineering and Regenerative Medicine, Fujian Province University, Fuzhou, 350122, Fujian, China.
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28
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Song Y, Zhang Y, Pan Y, He J, Wang Y, Chen W, Guo J, Deng H, Xue Y, Fang X, Liang X. The microtubule end-binding affinity of EB1 is enhanced by a dimeric organization that is susceptible to phosphorylation. J Cell Sci 2020; 133:jcs241216. [PMID: 32152183 DOI: 10.1242/jcs.241216] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Accepted: 02/28/2020] [Indexed: 12/18/2022] Open
Abstract
In cells, microtubule dynamics are regulated by plus-end tracking proteins (+TIPs). End-binding protein 1 (EB1, also known as MAPRE1) acts as a master regulator of +TIP networks by targeting the growing ends of microtubules and recruiting other factors. However, the molecular mechanism underlying high-affinity binding of EB1 to microtubule ends remains an open area of research. Using single-molecule imaging, we show that the end-binding kinetics of EB1 change when the polymerization and hydrolysis rates of tubulin dimers are altered, confirming that EB1 binds to GTP-tubulin and/or GDP-Pi-tubulin at microtubule growing ends. The affinity of wild-type EB1 to these sites is higher than that of monomeric EB1 mutants, suggesting that both calponin homology domains present in the EB1 dimer contribute to end binding. Introduction of phosphomimetic mutations into the EB1 linker domain weakens the end-binding affinity and confers a more curved conformation on the EB1 dimer without compromising dimerization, suggesting that the overall architecture of EB1 is important for its end-binding affinity. Taken together, our results provide insights into how the high-affinity end-binding of EB1 is achieved and how this activity may be regulated in cells.
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Affiliation(s)
- Yinlong Song
- Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, 100084 Beijing, China
| | - Yikan Zhang
- Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, 100084 Beijing, China
| | - Ying Pan
- Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, 100084 Beijing, China
- Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, 100084 Beijing, China
| | - Jianfeng He
- Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, 100084 Beijing, China
| | - Yan Wang
- Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, 100084 Beijing, China
| | - Wei Chen
- Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, 100084 Beijing, China
| | - Jing Guo
- Protein Chemistry Facility at the Center for Biomedical Analysis of Tsinghua University, 100084 Beijing, China
| | - Haiteng Deng
- Protein Chemistry Facility at the Center for Biomedical Analysis of Tsinghua University, 100084 Beijing, China
| | - Yi Xue
- Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, 100084 Beijing, China
- Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, 100084 Beijing, China
| | - Xianyang Fang
- Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, 100084 Beijing, China
| | - Xin Liang
- Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, 100084 Beijing, China
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29
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Rajaei S, Karima S, Sepasi Tehrani H, Shateri S, Mahmoodi Baram S, Mahdavi M, Mokhtari F, Alimohammadi A, Tafakhori A, Amiri A, Aghamollaii V, Fatemi H, Rajabibazl M, Kobarfard F, Gorji A. Conformational change and GTPase activity of human tubulin: A comparative study on Alzheimer's disease and healthy brain. J Neurochem 2020; 155:207-224. [PMID: 32196663 DOI: 10.1111/jnc.15009] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 03/13/2020] [Accepted: 03/14/2020] [Indexed: 11/26/2022]
Abstract
In Alzheimer's disease (AD), the most common form of dementia, microtubules (MTs) play a pivotal role through their highly dynamic structure and instability. They mediate axonal transport that is crucial to synaptic viability. MT assembly, dynamic instability and stabilization are modulated by tau proteins, whose detachment initiates MT disintegration. Albeit extensive research, the role of GTPase activity in molecular mechanism of stability remains controversial. We hypothesized that GTPase activity is altered in AD leading to microtubule dynamic dysfunction and ultimately to neuronal death. In this paper, fresh tubulin was purified by chromatography from normal young adult, normal aged, and Alzheimer's brain tissues. Polymerization pattern, assembly kinetics and dynamics, critical concentration, GTPase activity, interaction with tau, intermolecular geometry, and conformational changes were explored via Förster Resonance Energy Transfer (FRET) and various spectroscopy methods. Results showed slower MT assembly process in samples from the brains of people with AD compared with normal young and aged brains. This observation was characterized by prolonged lag phase and increased critical and inactive concentration of tubulin. In addition, the GTPase activity in samples from AD brains was significantly higher than in both normal young and normal aged samples, concurrent with profound conformational changes and contracted intermolecular MT-tau distances as revealed by FRET. These alterations were partially restored in the presence of a microtubule stabilizer, paclitaxel. We proposed that alterations of both tubulin function and GTPase activity may be involved in the molecular neuropathogenesis of AD, thus providing new avenues for therapeutic approaches.
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Affiliation(s)
- Shima Rajaei
- Department of Clinical Biochemistry, School of Medicine, Shahid Beheshti University of Medical Sciences (SBMU), Tehran, Iran
| | - Saeed Karima
- Department of Clinical Biochemistry, School of Medicine, Shahid Beheshti University of Medical Sciences (SBMU), Tehran, Iran
| | | | - Somayeh Shateri
- Department of Clinical Biochemistry, School of Medicine, Shahid Beheshti University of Medical Sciences (SBMU), Tehran, Iran
| | - Somayeh Mahmoodi Baram
- Department of Clinical Biochemistry, School of Medicine, Shahid Beheshti University of Medical Sciences (SBMU), Tehran, Iran.,HealthWeX Clinical Research Co., Ltd., Toronto, ON, Canada
| | - Meisam Mahdavi
- Department of Clinical Biochemistry, School of Medicine, Shahid Beheshti University of Medical Sciences (SBMU), Tehran, Iran
| | - Farzad Mokhtari
- HealthWeX Clinical Research Co., Ltd., Toronto, ON, Canada.,Department of Biochemistry, Institute of Biochemistry and Biophysics (IBB), University of Tehran, Tehran, Iran
| | - Alimohammad Alimohammadi
- Research Center of Tehran Forensic Medicine Organization, Forensic Medicine, Legal Medicine Organization Research Center, Tehran, Iran
| | - Abbas Tafakhori
- Iranian Center of Neurological research, Tehran University of Medical Sciences, Tehran, Iran
| | - Abolfazl Amiri
- Research Center of Tehran Forensic Medicine Organization, Forensic Medicine, Legal Medicine Organization Research Center, Tehran, Iran
| | - Vajiheh Aghamollaii
- Neurology Department, Roozbeh Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Hamid Fatemi
- HealthWeX Clinical Research Co., Ltd., Toronto, ON, Canada
| | - Masoumeh Rajabibazl
- Department of Clinical Biochemistry, School of Medicine, Shahid Beheshti University of Medical Sciences (SBMU), Tehran, Iran
| | - Farzad Kobarfard
- Department of Medicinal Chemistry, School of Pharmacy, Shahid Beheshti University of Medical Sciences (SBMU), Tehran, Iran
| | - Ali Gorji
- Department of Neurology and Department of Neurosurgery, Westfälische Wilhelms-Universität Münster, Münster, Germany
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30
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Spatio-temporal correlations between catastrophe events in a microtubule bundle: a computational study. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2020; 49:215-222. [PMID: 32157375 DOI: 10.1007/s00249-020-01427-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 02/25/2020] [Indexed: 10/24/2022]
Abstract
We explore correlations between dynamics of different microtubules in a bundle, via numerical simulations, using a one-dimensional stochastic model of a microtubule. The guanosine triphosphate (GTP)-bound tubulins undergo diffusion-limited binding to the tip. Random hydrolysis events take place along the microtubule and converts the bound GTP in tubulin to guanosine diphosphate (GDP). The microtubule starts depolymerising when the monomer at the tip becomes GDP-bound; in this case, detachment of GDP-tubulin ensues and continues until either GTP-bound tubulin is exposed or complete depolymerisation is achieved. In the latter case, the microtubule is defined to have undergone a "catastrophe". Our results show that, in general, the dynamics of growth and catastrophe in different microtubules are coupled to each other; the closer the microtubules are, the stronger the coupling. In particular, all microtubules grow slower, on average, when brought closer together. The reduction in growth velocity also leads to more frequent catastrophes. More dramatically, catastrophe events in the different microtubules forming a bundle are found to be correlated; a catastrophe event in one microtubule is more likely to be followed by a similar event in the same microtubule. This propensity of bunching disappears when the microtubules move farther apart.
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31
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Bompard G, van Dijk J, Cau J, Lannay Y, Marcellin G, Lawera A, van der Laan S, Rogowski K. CSAP Acts as a Regulator of TTLL-Mediated Microtubule Glutamylation. Cell Rep 2019; 25:2866-2877.e5. [PMID: 30517872 DOI: 10.1016/j.celrep.2018.10.095] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Revised: 12/22/2017] [Accepted: 10/25/2018] [Indexed: 01/22/2023] Open
Abstract
Tubulin glutamylation is a reversible posttranslational modification that accumulates on stable microtubules (MTs). While abnormally high levels of this modification lead to a number of disorders such as male sterility, retinal degeneration, and neurodegeneration, very little is known about the molecular mechanisms underlying the regulation of glutamylase activity. Here, we found that CSAP forms a complex with TTLL5, and we demonstrate that the two proteins regulate their reciprocal abundance. Moreover, we show that CSAP increases TTLL5-mediated glutamylation and identify the TTLL5-interacting domain. Deletion of this domain leads to complete loss of CSAP activating function without impacting its MT binding. Binding of CSAP to TTLL5 promotes relocalization of TTLL5 toward MTs. Finally, we show that CSAP binds and activates all of the remaining autonomously active TTLL glutamylases. As such, we present CSAP as a major regulator of tubulin glutamylation and associated functions.
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Affiliation(s)
- Guillaume Bompard
- Institute of Human Genetics (IGH), UMR9002 CNRS-University of Montpellier, 34094 Cedex 5, 141 Rue de la Cardonille, 34090 Montpellier, France
| | - Juliette van Dijk
- Institute of Human Genetics (IGH), UMR9002 CNRS-University of Montpellier, 34094 Cedex 5, 141 Rue de la Cardonille, 34090 Montpellier, France
| | - Julien Cau
- Institute of Human Genetics (IGH), UMR9002 CNRS-University of Montpellier, 34094 Cedex 5, 141 Rue de la Cardonille, 34090 Montpellier, France
| | - Yoann Lannay
- Institute of Human Genetics (IGH), UMR9002 CNRS-University of Montpellier, 34094 Cedex 5, 141 Rue de la Cardonille, 34090 Montpellier, France
| | - Guillaume Marcellin
- Institute of Human Genetics (IGH), UMR9002 CNRS-University of Montpellier, 34094 Cedex 5, 141 Rue de la Cardonille, 34090 Montpellier, France
| | - Aleksandra Lawera
- Institute of Human Genetics (IGH), UMR9002 CNRS-University of Montpellier, 34094 Cedex 5, 141 Rue de la Cardonille, 34090 Montpellier, France
| | - Siem van der Laan
- Institute of Human Genetics (IGH), UMR9002 CNRS-University of Montpellier, 34094 Cedex 5, 141 Rue de la Cardonille, 34090 Montpellier, France
| | - Krzysztof Rogowski
- Institute of Human Genetics (IGH), UMR9002 CNRS-University of Montpellier, 34094 Cedex 5, 141 Rue de la Cardonille, 34090 Montpellier, France.
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32
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Kuo YW, Trottier O, Howard J. Predicted Effects of Severing Enzymes on the Length Distribution and Total Mass of Microtubules. Biophys J 2019; 117:2066-2078. [PMID: 31708162 DOI: 10.1016/j.bpj.2019.10.027] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 10/17/2019] [Accepted: 10/22/2019] [Indexed: 01/12/2023] Open
Abstract
Microtubules are dynamic cytoskeletal polymers whose growth and shrinkage are highly regulated as eukaryotic cells change shape, move, and divide. One family of microtubule regulators includes the ATP-hydrolyzing enzymes spastin, katanin, and fidgetin, which sever microtubule polymers into shorter fragments. Paradoxically, severases can increase microtubule number and mass in cells. Recent work with purified spastin and katanin accounts for this phenotype by showing that, in addition to severing, these enzymes modulate microtubule dynamics by accelerating the conversion of microtubules from their shrinking to their growing states and thereby promoting their regrowth. This leads to the observed exponential increase in microtubule mass. Spastin also influences the steady-state distribution of microtubule lengths, changing it from an exponential, as predicted by models of microtubule dynamic instability, to a peaked distribution. This effect of severing and regrowth by spastin on the microtubule length distribution has not been explained theoretically. To solve this problem, we formulated and solved a master equation for the time evolution of microtubule lengths in the presence of severing and microtubule dynamic instability. We then obtained numerical solutions to the steady-state length distribution and showed that the rate of severing and the speed of microtubule growth are the dominant parameters determining the steady-state length distribution. Furthermore, we found that the amplification rate is predicted to increase with severing, which is, to our knowledge, a new result. Our results establish a theoretical basis for how severing and dynamics together can serve to nucleate new microtubules, constituting a versatile mechanism to regulate microtubule length and mass.
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Affiliation(s)
- Yin-Wei Kuo
- Department of Chemistry, Yale University, New Haven, Connecticut; Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut
| | - Olivier Trottier
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut; Department of Physics, Yale University, New Haven, Connecticut
| | - Jonathon Howard
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut.
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33
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Jonasson EM, Mauro AJ, Li C, Labuz EC, Mahserejian SM, Scripture JP, Gregoretti IV, Alber M, Goodson HV. Behaviors of individual microtubules and microtubule populations relative to critical concentrations: dynamic instability occurs when critical concentrations are driven apart by nucleotide hydrolysis. Mol Biol Cell 2019; 31:589-618. [PMID: 31577530 PMCID: PMC7202068 DOI: 10.1091/mbc.e19-02-0101] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The concept of critical concentration (CC) is central to understanding the behavior of microtubules (MTs) and other cytoskeletal polymers. Traditionally, these polymers are understood to have one CC, measured in multiple ways and assumed to be the subunit concentration necessary for polymer assembly. However, this framework does not incorporate dynamic instability (DI), and there is work indicating that MTs have two CCs. We use our previously established simulations to confirm that MTs have (at least) two experimentally relevant CCs and to clarify the behavior of individuals and populations relative to the CCs. At free subunit concentrations above the lower CC (CCElongation), growth phases of individual filaments can occur transiently; above the higher CC (CCNetAssembly), the population’s polymer mass will increase persistently. Our results demonstrate that most experimental CC measurements correspond to CCNetAssembly, meaning that “typical” DI occurs below the concentration traditionally considered necessary for polymer assembly. We report that [free tubulin] at steady state does not equal CCNetAssembly, but instead approaches CCNetAssembly asymptotically as [total tubulin] increases, and depends on the number of stable MT nucleation sites. We show that the degree of separation between CCElongation and CCNetAssembly depends on the rate of nucleotide hydrolysis. This clarified framework helps explain and unify many experimental observations.
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Affiliation(s)
- Erin M Jonasson
- Department of Chemistry and Biochemistry.,Department of Natural Sciences, Saint Martin's University, Lacey, WA 98503
| | - Ava J Mauro
- Department of Chemistry and Biochemistry.,Department of Applied and Computational Mathematics and Statistics, and.,Department of Mathematics and Statistics, University of Massachusetts Amherst, Amherst, MA 01003
| | - Chunlei Li
- Department of Applied and Computational Mathematics and Statistics, and
| | | | | | | | | | - Mark Alber
- Department of Applied and Computational Mathematics and Statistics, and.,Department of Mathematics, University of California, Riverside, Riverside, CA 92521
| | - Holly V Goodson
- Department of Chemistry and Biochemistry.,Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556
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34
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Wu S, Yan M, Li L, Mao B, Wong CKC, Ge R, Lian Q, Cheng CY. mTORC1/rpS6 and spermatogenic function in the testis-insights from the adjudin model. Reprod Toxicol 2019; 89:54-66. [PMID: 31278979 PMCID: PMC6825331 DOI: 10.1016/j.reprotox.2019.07.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 06/12/2019] [Accepted: 07/02/2019] [Indexed: 12/13/2022]
Abstract
mTORC1/rpS6 signaling complex promoted Sertoli blood-testis barrier (BTB) remodeling by perturbing Sertoli cell-cell adhesion site known as the basal ectoplasmic specialization (ES). mTORC1/rpS6 complex also promoted disruption of spermatid adhesion at the Sertoli-spermatid interface called the apical ES. Herein, we performed analyses using the adjudin (a non-hormonal male contraceptive drug under development) model, wherein adjudin was known to perturb apical and basal ES function when used at high dose. Through direct administration of adjudin to the testis, adjudin at doses that failed to perturb BTB integrity per se, overexpression of an rpS6 phosphomimetic (i.e., constitutively active) mutant (i.e., p-rpS6-MT) that modified BTB function considerably potentiated adjudin efficacy. This led to disorderly spatial expression of proteins necessary to maintain the proper cytoskeletal organization of F-actin and microtubules (MTs) across the seminiferous epithelium, leading to germ cell exfoliation and aspermatogenesis. These findings yielded important insights regarding the role of mTORC1/rpS6 signaling complex in regulating BTB homeostasis.
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Affiliation(s)
- Siwen Wu
- The Second Affiliated Hospital & Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, China; The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Ave, New York, 10065, United States
| | - Ming Yan
- The Second Affiliated Hospital & Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, China; Jiangsu Key Laboratory of Drug Screening, Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, China Pharmaceutical University, Nanjing, China
| | - Linxi Li
- The Second Affiliated Hospital & Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, China; The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Ave, New York, 10065, United States
| | - Baiping Mao
- The Second Affiliated Hospital & Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, China; The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Ave, New York, 10065, United States
| | - Chris K C Wong
- Department of Biology, Croucher Institute for Environmental Sciences, Hong Kong Baptist University, Hong Kong, China
| | - Renshan Ge
- The Second Affiliated Hospital & Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, China
| | - Qingquan Lian
- The Second Affiliated Hospital & Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, China
| | - C Yan Cheng
- The Second Affiliated Hospital & Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, China; The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Ave, New York, 10065, United States.
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35
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Abstract
Microtubule minus ends are inherently more stable than plus ends despite the fact that free tubulin associates more avidly to the plus end. In this issue, Strothman et al. (2019. J. Cell Biol. https://doi.org/10.1083/jcb.201905019) measure, for the first time, the off-rate for GTP-tubulin and find that it is different for the two ends, suggesting that this parameter may control the transition to disassembly at microtubule ends.
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Affiliation(s)
- Linda Wordeman
- Department of Physiology and Biophysics, University of Washington School of Medicine, Seattle, WA
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36
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Adib R, Montgomery JM, Atherton J, O'Regan L, Richards MW, Straatman KR, Roth D, Straube A, Bayliss R, Moores CA, Fry AM. Mitotic phosphorylation by NEK6 and NEK7 reduces the microtubule affinity of EML4 to promote chromosome congression. Sci Signal 2019; 12:eaaw2939. [PMID: 31409757 DOI: 10.1126/scisignal.aaw2939] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
EML4 is a microtubule-associated protein that promotes microtubule stability. We investigated its regulation across the cell cycle and found that EML4 was distributed as punctate foci along the microtubule lattice in interphase but exhibited reduced association with spindle microtubules in mitosis. Microtubule sedimentation and cryo-electron microscopy with 3D reconstruction revealed that the basic N-terminal domain of EML4 mediated its binding to the acidic C-terminal tails of α- and β-tubulin on the microtubule surface. The mitotic kinases NEK6 and NEK7 phosphorylated the EML4 N-terminal domain at Ser144 and Ser146 in vitro, and depletion of these kinases in cells led to increased EML4 binding to microtubules in mitosis. An S144A-S146A double mutant not only bound inappropriately to mitotic microtubules but also increased their stability and interfered with chromosome congression. In addition, constitutive activation of NEK6 or NEK7 reduced the association of EML4 with interphase microtubules. Together, these data support a model in which NEK6- and NEK7-dependent phosphorylation promotes the dissociation of EML4 from microtubules in mitosis in a manner that is required for efficient chromosome congression.
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Affiliation(s)
- Rozita Adib
- Department of Molecular and Cell Biology, University of Leicester, Lancaster Road, Leicester LE1 9HN, UK
| | - Jessica M Montgomery
- Department of Molecular and Cell Biology, University of Leicester, Lancaster Road, Leicester LE1 9HN, UK
| | - Joseph Atherton
- Institute of Structural and Molecular Biology, Birkbeck College, Malet Street, London WC1E 7HX, UK
| | - Laura O'Regan
- Department of Molecular and Cell Biology, University of Leicester, Lancaster Road, Leicester LE1 9HN, UK
| | - Mark W Richards
- Astbury Centre for Structural Molecular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Kees R Straatman
- Centre for Core Biotechnology Services, University of Leicester, University Road, Leicester LE1 7RH, UK
| | - Daniel Roth
- Centre for Mechanochemical Cell Biology and Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry CV4 7AL, UK
| | - Anne Straube
- Centre for Mechanochemical Cell Biology and Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry CV4 7AL, UK
| | - Richard Bayliss
- Astbury Centre for Structural Molecular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Carolyn A Moores
- Institute of Structural and Molecular Biology, Birkbeck College, Malet Street, London WC1E 7HX, UK
| | - Andrew M Fry
- Department of Molecular and Cell Biology, University of Leicester, Lancaster Road, Leicester LE1 9HN, UK.
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37
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Barbier P, Zejneli O, Martinho M, Lasorsa A, Belle V, Smet-Nocca C, Tsvetkov PO, Devred F, Landrieu I. Role of Tau as a Microtubule-Associated Protein: Structural and Functional Aspects. Front Aging Neurosci 2019; 11:204. [PMID: 31447664 PMCID: PMC6692637 DOI: 10.3389/fnagi.2019.00204] [Citation(s) in RCA: 264] [Impact Index Per Article: 52.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 07/18/2019] [Indexed: 12/24/2022] Open
Abstract
Microtubules (MTs) play a fundamental role in many vital processes such as cell division and neuronal activity. They are key structural and functional elements in axons, supporting neurite differentiation and growth, as well as transporting motor proteins along the axons, which use MTs as support tracks. Tau is a stabilizing MT associated protein, whose functions are mainly regulated by phosphorylation. A disruption of the MT network, which might be caused by Tau loss of function, is observed in a group of related diseases called tauopathies, which includes Alzheimer’s disease (AD). Tau is found hyperphosphorylated in AD, which might account for its loss of MT stabilizing capacity. Since destabilization of MTs after dissociation of Tau could contribute to toxicity in neurodegenerative diseases, a molecular understanding of this interaction and its regulation is essential.
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Affiliation(s)
- Pascale Barbier
- Fac Pharm, Aix Marseille Univ., Centre National de la Recherche Scientifique (CNRS), Inst Neurophysiopathol (INP), Fac Pharm, Marseille, France
| | - Orgeta Zejneli
- Univ. Lille, Centre National de la Recherche Scientifique (CNRS), UMR 8576, Unité de Glycobiologie Structurale et Fonctionnelle (UGSF), Lille, France.,Univ. Lille, Institut National de la Santé et de la Recherche Médicale (INSERM), CHU-Lille, UMR-S 1172, Centre de Recherche Jean-Pierre AUBERT (JPArc), Lille, France
| | - Marlène Martinho
- Aix Marseille Univ., Centre National de la Recherche Scientifique (CNRS), UMR 7281, Bioénergétique et Ingénierie des Protéines (BIP), Marseille, France
| | - Alessia Lasorsa
- Univ. Lille, Centre National de la Recherche Scientifique (CNRS), UMR 8576, Unité de Glycobiologie Structurale et Fonctionnelle (UGSF), Lille, France
| | - Valérie Belle
- Aix Marseille Univ., Centre National de la Recherche Scientifique (CNRS), UMR 7281, Bioénergétique et Ingénierie des Protéines (BIP), Marseille, France
| | - Caroline Smet-Nocca
- Univ. Lille, Centre National de la Recherche Scientifique (CNRS), UMR 8576, Unité de Glycobiologie Structurale et Fonctionnelle (UGSF), Lille, France
| | - Philipp O Tsvetkov
- Fac Pharm, Aix Marseille Univ., Centre National de la Recherche Scientifique (CNRS), Inst Neurophysiopathol (INP), Fac Pharm, Marseille, France
| | - François Devred
- Fac Pharm, Aix Marseille Univ., Centre National de la Recherche Scientifique (CNRS), Inst Neurophysiopathol (INP), Fac Pharm, Marseille, France
| | - Isabelle Landrieu
- Univ. Lille, Centre National de la Recherche Scientifique (CNRS), UMR 8576, Unité de Glycobiologie Structurale et Fonctionnelle (UGSF), Lille, France
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38
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Yan M, Li L, Mao B, Li H, Li SYT, Mruk D, Silvestrini B, Lian Q, Ge R, Cheng CY. mTORC1/rpS6 signaling complex modifies BTB transport function: an in vivo study using the adjudin model. Am J Physiol Endocrinol Metab 2019; 317:E121-E138. [PMID: 31112404 PMCID: PMC6689739 DOI: 10.1152/ajpendo.00553.2018] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 04/30/2019] [Accepted: 05/05/2019] [Indexed: 12/13/2022]
Abstract
Studies have shown that the mTORC1/rpS6 signaling cascade regulates Sertoli cell blood-testis barrier (BTB) dynamics. For instance, specific inhibition of mTORC1 by treating Sertoli cells with rapamycin promotes the Sertoli cell barrier, making it "tighter." However, activation of mTORC1 by overexpressing a full-length rpS6 cDNA clone (i.e., rpS6-WT, wild type) in Sertoli cells promotes BTB remodeling, making the barrier "leaky." Also, there is an increase in rpS6 and p-rpS6 (phosphorylated and activated rpS6) expression at the BTB in testes at stages VIII-IX of the epithelial cycle, and it coincides with BTB remodeling to support the transport of preleptotene spermatocytes across the barrier, illustrating that rpS6 is a BTB-modifying signaling protein. Herein, we used a constitutively active, quadruple phosphomimetic mutant of rpS6, namely p-rpS6-MT of p-rpS6-S235E/S236E/S240E/S244E, wherein Ser (S) was converted to Glu (E) at amino acid residues 235, 236, 240, and 244 from the NH2 terminus by site-directed mutagenesis, for its overexpression in rat testes in vivo using the Polyplus in vivo jet-PEI transfection reagent with high transfection efficiency. Overexpression of this p-rpS6-MT was capable of inducing BTB remodeling, making the barrier "leaky." This thus promoted the entry of the nonhormonal male contraceptive adjudin into the adluminal compartment in the seminiferous epithelium to induce germ cell exfoliation. Combined overexpression of p-rpS6-MT with a male contraceptive (e.g., adjudin) potentiated the drug bioavailability by modifying the BTB. This approach thus lowers intrinsic drug toxicity due to a reduced drug dose, further characterizing the biology of BTB transport function.
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Affiliation(s)
- Ming Yan
- Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council , New York, New York
| | - Linxi Li
- Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council , New York, New York
- Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University , Wenzhou, Zhejiang , China
| | - Baiping Mao
- Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council , New York, New York
- Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University , Wenzhou, Zhejiang , China
| | - Huitao Li
- Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council , New York, New York
- Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University , Wenzhou, Zhejiang , China
| | - Stephen Y T Li
- Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council , New York, New York
| | - Dolores Mruk
- Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council , New York, New York
| | | | - Qingquan Lian
- Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University , Wenzhou, Zhejiang , China
| | - Renshan Ge
- Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University , Wenzhou, Zhejiang , China
| | - C Yan Cheng
- Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council , New York, New York
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39
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A Survey on Tubulin and Arginine Methyltransferase Families Sheds Light on P. lividus Embryo as Model System for Antiproliferative Drug Development. Int J Mol Sci 2019; 20:ijms20092136. [PMID: 31052191 PMCID: PMC6539552 DOI: 10.3390/ijms20092136] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 04/27/2019] [Indexed: 01/18/2023] Open
Abstract
Tubulins and microtubules (MTs) represent targets for taxane-based chemotherapy. To date, several lines of evidence suggest that effectiveness of compounds binding tubulin often relies on different post-translational modifications on tubulins. Among them, methylation was recently associated to drug resistance mechanisms impairing taxanes binding. The sea urchin is recognized as a research model in several fields including fertilization, embryo development and toxicology. To date, some α- and β-tubulin genes have been identified in P. lividus, while no data are available in echinoderms for arginine methyl transferases (PRMT). To evaluate the exploiting of the sea urchin embryo in the field of antiproliferative drug development, we carried out a survey of the expressed α- and β-tubulin gene sets, together with a comprehensive analysis of the PRMT gene family and of the methylable arginine residues in P. lividus tubulins. Because of their specificities, the sea urchin embryo may represent an interesting tool for dissecting mechanisms of tubulin targeting drug action. Therefore, results herein reported provide evidences supporting the P. lividus embryo as animal system for testing antiproliferative drugs.
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40
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MTrack: Automated Detection, Tracking, and Analysis of Dynamic Microtubules. Sci Rep 2019; 9:3794. [PMID: 30846705 PMCID: PMC6405942 DOI: 10.1038/s41598-018-37767-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Accepted: 12/05/2018] [Indexed: 11/11/2022] Open
Abstract
Microtubules are polar, dynamic filaments fundamental to many cellular processes. In vitro reconstitution approaches with purified tubulin are essential to elucidate different aspects of microtubule behavior. To date, deriving data from fluorescence microscopy images by manually creating and analyzing kymographs is still commonplace. Here, we present MTrack, implemented as a plug-in for the open-source platform Fiji, which automatically identifies and tracks dynamic microtubules with sub-pixel resolution using advanced objection recognition. MTrack provides automatic data interpretation yielding relevant parameters of microtubule dynamic instability together with population statistics. The application of our software produces unbiased and comparable quantitative datasets in a fully automated fashion. This helps the experimentalist to achieve higher reproducibility at higher throughput on a user-friendly platform. We use simulated data and real data to benchmark our algorithm and show that it reliably detects, tracks, and analyzes dynamic microtubules and achieves sub-pixel precision even at low signal-to-noise ratios.
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41
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Spastin is a dual-function enzyme that severs microtubules and promotes their regrowth to increase the number and mass of microtubules. Proc Natl Acad Sci U S A 2019; 116:5533-5541. [PMID: 30837315 PMCID: PMC6431158 DOI: 10.1073/pnas.1818824116] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The remodeling of the microtubule cytoskeleton underlies dynamic cellular processes, such as mitosis, ciliogenesis, and neuronal morphogenesis. An important class of microtubule remodelers comprises the severases-spastin, katanin, and fidgetin-which cut microtubules into shorter fragments. While severing activity might be expected to break down the microtubule cytoskeleton, inhibiting these enzymes in vivo actually decreases, rather increases, the number of microtubules, suggesting that severases have a nucleation-like activity. To resolve this paradox, we reconstituted Drosophila spastin in a dynamic microtubule assay and discovered that it is a dual-function enzyme. In addition to its ATP-dependent severing activity, spastin is an ATP-independent regulator of microtubule dynamics that slows shrinkage and increases rescue. We observed that spastin accumulates at shrinking ends; this increase in spastin concentration may underlie the increase in rescue frequency and the slowdown in shortening. The changes in microtubule dynamics promote microtubule regrowth so that severed microtubule fragments grow, leading to an increase in the number and mass of microtubules. A mathematical model shows that spastin's effect on microtubule dynamics is essential for this nucleation-like activity: spastin switches microtubules into a state where the net flux of tubulin onto each polymer is positive, leading to the observed exponential increase in microtubule mass. This increase in the microtubule mass accounts for spastin's in vivo phenotypes.
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42
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van Haren J, Wittmann T. Microtubule Plus End Dynamics - Do We Know How Microtubules Grow?: Cells boost microtubule growth by promoting distinct structural transitions at growing microtubule ends. Bioessays 2019; 41:e1800194. [PMID: 30730055 PMCID: PMC7021488 DOI: 10.1002/bies.201800194] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 12/22/2018] [Indexed: 12/31/2022]
Abstract
Microtubules form a highly dynamic filament network in all eukaryotic cells. Individual microtubules grow by tubulin dimer subunit addition and frequently switch between phases of growth and shortening. These unique dynamics are powered by GTP hydrolysis and drive microtubule network remodeling, which is central to eukaryotic cell biology and morphogenesis. Yet, our knowledge of the molecular events at growing microtubule ends remains incomplete. Here, recent ultrastructural, biochemical and cell biological data are integrated to develop a realistic model of growing microtubule ends comprised of structurally distinct but biochemically overlapping zones. Proteins that recognize microtubule lattice conformations associated with specific tubulin guanosine nucleotide states may independently control major structural transitions at growing microtubule ends. A model is proposed in which tubulin dimer addition and subsequent closure of the MT wall are optimized in cells to achieve rapid physiological microtubule growth.
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Affiliation(s)
- Jeffrey van Haren
- Department of Cell and Tissue Biology, University of California San Francisco, 513 Parnassus Avenue, San Francisco, CA, 94143, USA
| | - Torsten Wittmann
- Department of Cell and Tissue Biology, University of California San Francisco, 513 Parnassus Avenue, San Francisco, CA, 94143, USA
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43
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Regulation of Blood-Testis Barrier (BTB) Dynamics, Role of Actin-, and Microtubule-Based Cytoskeletons. Methods Mol Biol 2019; 1748:229-243. [PMID: 29453575 DOI: 10.1007/978-1-4939-7698-0_16] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The blood-testis barrier (BTB) is an important ultrastructure in the testis that supports meiosis and postmeiotic spermatid development since a delay in the establishment of a functional Sertoli cell barrier during postnatal development in rats or mice by 17-20 day postpartum (dpp) would lead to a delay of the first wave of meiosis. Furthermore, irreversible disruption of the BTB by toxicants also induces infertility in rodents. Herein, we summarize recent findings that BTB dynamics (i.e., disassembly, reassembly, and stabilization) are supported by the concerted efforts of the actin- and microtubule (MT)-based cytoskeletons. We focus on the role of two actin nucleation protein complexes, namely, the Arp2/3 (actin-related protein 2/3) complex and formin 1 (or the formin 1/spire 1 complex) known to induce actin nucleation, respectively, by conferring plasticity to actin cytoskeleton. We also focus on the MT plus (+)-end tracking protein (+TIP) EB1 (end-binding protein 1) which is known to confer MT stabilization. Furthermore, we discuss in particular how the interactions of these proteins modulate BTB dynamics during spermatogenesis. These findings also yield a novel hypothetical concept regarding the molecular mechanism that modulates BTB function.
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44
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Shrestha S, Hazelbaker M, Yount AL, Walczak CE. Emerging Insights into the Function of Kinesin-8 Proteins in Microtubule Length Regulation. Biomolecules 2018; 9:biom9010001. [PMID: 30577528 PMCID: PMC6359247 DOI: 10.3390/biom9010001] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 12/15/2018] [Accepted: 12/17/2018] [Indexed: 12/14/2022] Open
Abstract
Proper regulation of microtubules (MTs) is critical for the execution of diverse cellular processes, including mitotic spindle assembly and chromosome segregation. There are a multitude of cellular factors that regulate the dynamicity of MTs and play critical roles in mitosis. Members of the Kinesin-8 family of motor proteins act as MT-destabilizing factors to control MT length in a spatially and temporally regulated manner. In this review, we focus on recent advances in our understanding of the structure and function of the Kinesin-8 motor domain, and the emerging contributions of the C-terminal tail of Kinesin-8 proteins to regulate motor activity and localization.
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Affiliation(s)
- Sanjay Shrestha
- Medical Sciences Program, Indiana University, Bloomington, IN 47405, USA.
| | - Mark Hazelbaker
- Medical Sciences Program, Indiana University, Bloomington, IN 47405, USA.
| | - Amber L Yount
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, IN 47405, USA.
| | - Claire E Walczak
- Medical Sciences Program, Indiana University, Bloomington, IN 47405, USA.
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45
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Chang Q, Yang H, Wang M, Wei H, Hu F. Role of Microtubule-Associated Protein in Autism Spectrum Disorder. Neurosci Bull 2018; 34:1119-1126. [PMID: 29936584 PMCID: PMC6246838 DOI: 10.1007/s12264-018-0246-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Accepted: 04/19/2018] [Indexed: 12/14/2022] Open
Abstract
Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by deficits in social interaction and communication, along with repetitive and restrictive patterns of behaviors or interests. Normal brain development is crucial to behavior and cognition in adulthood. Abnormal brain development, such as synaptic and myelin dysfunction, is involved in the pathogenesis of ASD. Microtubules and microtubule-associated proteins (MAPs) are important in regulating the processes of brain development, including neuron production and synaptic formation, as well as myelination. Increasing evidence suggests that the level of MAPs are changed in autistic patients and mouse models of ASD. Here, we discuss the roles of MAPs.
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Affiliation(s)
- Qiaoqiao Chang
- Department of Neurology, Shanxi Provincial People's Hospital, Affiliate of Shanxi Medical University, Taiyuan, 030012, China
| | - Hua Yang
- Department of Neurology, Shanxi Provincial People's Hospital, Affiliate of Shanxi Medical University, Taiyuan, 030012, China
| | - Min Wang
- Department of Neurology, Shanxi Provincial People's Hospital, Affiliate of Shanxi Medical University, Taiyuan, 030012, China
| | - Hongen Wei
- Department of Neurology, Shanxi Provincial People's Hospital, Affiliate of Shanxi Medical University, Taiyuan, 030012, China.
| | - Fengyun Hu
- Department of Neurology, Shanxi Provincial People's Hospital, Affiliate of Shanxi Medical University, Taiyuan, 030012, China.
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46
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Vicente-Blázquez A, González M, Álvarez R, Del Mazo S, Medarde M, Peláez R. Antitubulin sulfonamides: The successful combination of an established drug class and a multifaceted target. Med Res Rev 2018; 39:775-830. [PMID: 30362234 DOI: 10.1002/med.21541] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 09/02/2018] [Accepted: 09/06/2018] [Indexed: 12/13/2022]
Abstract
Tubulin, the microtubules and their dynamic behavior are amongst the most successful antitumor, antifungal, antiparasitic, and herbicidal drug targets. Sulfonamides are exemplary drugs with applications in the clinic, in veterinary and in the agrochemical industry. This review summarizes the actual state and recent progress of both fields looking from the double point of view of the target and its drugs, with special focus onto the structural aspects. The article starts with a brief description of tubulin structure and its dynamic assembly and disassembly into microtubules and other polymers. Posttranslational modifications and the many cellular means of regulating and modulating tubulin's biology are briefly presented in the tubulin code. Next, the structurally characterized drug binding sites, their occupying drugs and the effects they induce are described, emphasizing on the structural requirements for high potency, selectivity, and low toxicity. The second part starts with a summary of the favorable and highly tunable combination of physical-chemical and biological properties that render sulfonamides a prototypical example of privileged scaffolds with representatives in many therapeutic areas. A complete description of tubulin-binding sulfonamides is provided, covering the different species and drug sites. Some of the antimitotic sulfonamides have met with very successful applications and others less so, thus illustrating the advances, limitations, and future perspectives of the field. All of them combine in a mechanism of action and a clinical outcome that conform efficient drugs.
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Affiliation(s)
- Alba Vicente-Blázquez
- Laboratorio de Química Orgánica y Farmacéutica, Departamento de Ciencias Farmacéuticas, Universidad de Salamanca, Campus Miguel de Unamuno, Salamanca, Spain.,Facultad de Farmacia, Instituto de Investigación Biomédica de Salamanca (IBSAL), Universidad de Salamanca, Campus Miguel de Unamuno, Salamanca, Spain.,Facultad de Farmacia, Centro de Investigación de Enfermedades Tropicales de la Universidad de Salamanca (CIETUS), Universidad de Salamanca, Campus Miguel de Unamuno, Salamanca, Spain.,Laboratory of Cell Death and Cancer Therapy, Department of Molecular Biomedicine, Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
| | - Myriam González
- Laboratorio de Química Orgánica y Farmacéutica, Departamento de Ciencias Farmacéuticas, Universidad de Salamanca, Campus Miguel de Unamuno, Salamanca, Spain.,Facultad de Farmacia, Instituto de Investigación Biomédica de Salamanca (IBSAL), Universidad de Salamanca, Campus Miguel de Unamuno, Salamanca, Spain.,Facultad de Farmacia, Centro de Investigación de Enfermedades Tropicales de la Universidad de Salamanca (CIETUS), Universidad de Salamanca, Campus Miguel de Unamuno, Salamanca, Spain
| | - Raquel Álvarez
- Laboratorio de Química Orgánica y Farmacéutica, Departamento de Ciencias Farmacéuticas, Universidad de Salamanca, Campus Miguel de Unamuno, Salamanca, Spain.,Facultad de Farmacia, Instituto de Investigación Biomédica de Salamanca (IBSAL), Universidad de Salamanca, Campus Miguel de Unamuno, Salamanca, Spain.,Facultad de Farmacia, Centro de Investigación de Enfermedades Tropicales de la Universidad de Salamanca (CIETUS), Universidad de Salamanca, Campus Miguel de Unamuno, Salamanca, Spain
| | - Sara Del Mazo
- Laboratorio de Química Orgánica y Farmacéutica, Departamento de Ciencias Farmacéuticas, Universidad de Salamanca, Campus Miguel de Unamuno, Salamanca, Spain.,Facultad de Farmacia, Instituto de Investigación Biomédica de Salamanca (IBSAL), Universidad de Salamanca, Campus Miguel de Unamuno, Salamanca, Spain.,Facultad de Farmacia, Centro de Investigación de Enfermedades Tropicales de la Universidad de Salamanca (CIETUS), Universidad de Salamanca, Campus Miguel de Unamuno, Salamanca, Spain
| | - Manuel Medarde
- Laboratorio de Química Orgánica y Farmacéutica, Departamento de Ciencias Farmacéuticas, Universidad de Salamanca, Campus Miguel de Unamuno, Salamanca, Spain.,Facultad de Farmacia, Instituto de Investigación Biomédica de Salamanca (IBSAL), Universidad de Salamanca, Campus Miguel de Unamuno, Salamanca, Spain.,Facultad de Farmacia, Centro de Investigación de Enfermedades Tropicales de la Universidad de Salamanca (CIETUS), Universidad de Salamanca, Campus Miguel de Unamuno, Salamanca, Spain
| | - Rafael Peláez
- Laboratorio de Química Orgánica y Farmacéutica, Departamento de Ciencias Farmacéuticas, Universidad de Salamanca, Campus Miguel de Unamuno, Salamanca, Spain.,Facultad de Farmacia, Instituto de Investigación Biomédica de Salamanca (IBSAL), Universidad de Salamanca, Campus Miguel de Unamuno, Salamanca, Spain.,Facultad de Farmacia, Centro de Investigación de Enfermedades Tropicales de la Universidad de Salamanca (CIETUS), Universidad de Salamanca, Campus Miguel de Unamuno, Salamanca, Spain
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47
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Bergman ZJ, Wong J, Drubin DG, Barnes G. Microtubule dynamics regulation reconstituted in budding yeast lysates. J Cell Sci 2018; 132:jcs.219386. [PMID: 30185524 DOI: 10.1242/jcs.219386] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Accepted: 08/23/2018] [Indexed: 01/14/2023] Open
Abstract
Microtubules (MTs) are important for cellular structure, transport of cargoes and segregation of chromosomes and organelles during mitosis. The stochastic growth and shrinkage of MTs, known as dynamic instability, is necessary for these functions. Previous studies to determine how individual MT-associated proteins (MAPs) affect MT dynamics have been performed either through in vivo studies, which provide limited opportunity for observation of individual MTs or manipulation of conditions, or in vitro studies, which focus either on purified proteins, and therefore lack cellular complexity, or on cell extracts made from genetically intractable organisms. In order to investigate the ensemble activities of all MAPs on MT dynamics using lysates made from a genetically tractable organism, we developed a cell-free assay for budding yeast lysates using total internal reflection fluorescence (TIRF) microscopy. Lysates were prepared from yeast strains expressing GFP-tubulin. MT polymerization from pre-assembled MT seeds adhered to a coverslip was observed in real time. Through use of cell division cycle (cdc) and MT depolymerase mutants, we found that MT polymerization and dynamic instability are dependent on the cell cycle state and the activities of specific MAPs.
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Affiliation(s)
- Zane J Bergman
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA
| | - Jonathan Wong
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA
| | - David G Drubin
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA
| | - Georjana Barnes
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA
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48
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Louka P, Vasudevan KK, Guha M, Joachimiak E, Wloga D, Tomasi RFX, Baroud CN, Dupuis-Williams P, Galati DF, Pearson CG, Rice LM, Moresco JJ, Yates JR, Jiang YY, Lechtreck K, Dentler W, Gaertig J. Proteins that control the geometry of microtubules at the ends of cilia. J Cell Biol 2018; 217:4298-4313. [PMID: 30217954 PMCID: PMC6279374 DOI: 10.1083/jcb.201804141] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Revised: 07/25/2018] [Accepted: 08/31/2018] [Indexed: 11/22/2022] Open
Abstract
Louka et al. describe three conserved proteins that regulate the positions of microtubule ends near the tips of cilia. Mutations in two of these proteins cause a brain malformation, Joubert syndrome. Thus, microtubule ends in cilia may play a role in the pathology of Joubert syndrome. Cilia, essential motile and sensory organelles, have several compartments: the basal body, transition zone, and the middle and distal axoneme segments. The distal segment accommodates key functions, including cilium assembly and sensory activities. While the middle segment contains doublet microtubules (incomplete B-tubules fused to complete A-tubules), the distal segment contains only A-tubule extensions, and its existence requires coordination of microtubule length at the nanometer scale. We show that three conserved proteins, two of which are mutated in the ciliopathy Joubert syndrome, determine the geometry of the distal segment, by controlling the positions of specific microtubule ends. FAP256/CEP104 promotes A-tubule elongation. CHE-12/Crescerin and ARMC9 act as positive and negative regulators of B-tubule length, respectively. We show that defects in the distal segment dimensions are associated with motile and sensory deficiencies of cilia. Our observations suggest that abnormalities in distal segment organization cause a subset of Joubert syndrome cases.
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Affiliation(s)
- Panagiota Louka
- Department of Cellular Biology, University of Georgia, Athens, GA
| | | | - Mayukh Guha
- Department of Cellular Biology, University of Georgia, Athens, GA
| | - Ewa Joachimiak
- Laboratory of Cytoskeleton and Cilia Biology, Nencki Institute of Experimental Biology of Polish Academy of Sciences, Warsaw, Poland
| | - Dorota Wloga
- Laboratory of Cytoskeleton and Cilia Biology, Nencki Institute of Experimental Biology of Polish Academy of Sciences, Warsaw, Poland
| | - Raphaël F-X Tomasi
- Department of Mechanics, LadHyX, Ecole Polytechnique-Centre National de la Recherche Scientifique, Palaiseau, France
| | - Charles N Baroud
- Department of Mechanics, LadHyX, Ecole Polytechnique-Centre National de la Recherche Scientifique, Palaiseau, France
| | - Pascale Dupuis-Williams
- UMR-S1174 Institut National de la Santé et de la Recherche Médicale, Université Paris-Sud, Bat 443, Orsay, France.,École Supérieure de Physique et de Chimie Industrielles de la Ville de Paris, Paris, France
| | - Domenico F Galati
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Chad G Pearson
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Luke M Rice
- Departments of Biophysics and Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX
| | - James J Moresco
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA
| | - John R Yates
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA
| | - Yu-Yang Jiang
- Department of Cellular Biology, University of Georgia, Athens, GA
| | - Karl Lechtreck
- Department of Cellular Biology, University of Georgia, Athens, GA
| | - William Dentler
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS
| | - Jacek Gaertig
- Department of Cellular Biology, University of Georgia, Athens, GA
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49
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Lacroix B, Letort G, Pitayu L, Sallé J, Stefanutti M, Maton G, Ladouceur AM, Canman JC, Maddox PS, Maddox AS, Minc N, Nédélec F, Dumont J. Microtubule Dynamics Scale with Cell Size to Set Spindle Length and Assembly Timing. Dev Cell 2018; 45:496-511.e6. [PMID: 29787710 DOI: 10.1016/j.devcel.2018.04.022] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Revised: 03/22/2018] [Accepted: 04/24/2018] [Indexed: 12/22/2022]
Abstract
Successive cell divisions during embryonic cleavage create increasingly smaller cells, so intracellular structures must adapt accordingly. Mitotic spindle size correlates with cell size, but the mechanisms for this scaling remain unclear. Using live cell imaging, we analyzed spindle scaling during embryo cleavage in the nematode Caenorhabditis elegans and sea urchin Paracentrotus lividus. We reveal a common scaling mechanism, where the growth rate of spindle microtubules scales with cell volume, which explains spindle shortening. Spindle assembly timing is, however, constant throughout successive divisions. Analyses in silico suggest that controlling the microtubule growth rate is sufficient to scale spindle length and maintain a constant assembly timing. We tested our in silico predictions to demonstrate that modulating cell volume or microtubule growth rate in vivo induces a proportional spindle size change. Our results suggest that scalability of the microtubule growth rate when cell size varies adapts spindle length to cell volume.
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Affiliation(s)
- Benjamin Lacroix
- Institut Jacques Monod, CNRS, UMR 7592, University Paris Diderot, Sorbonne Paris Cité, 75205 Paris, France.
| | - Gaëlle Letort
- Institut Curie, Mines Paris Tech, Inserm, U900, PSL Research University, 75005 Paris, France
| | - Laras Pitayu
- Institut Jacques Monod, CNRS, UMR 7592, University Paris Diderot, Sorbonne Paris Cité, 75205 Paris, France
| | - Jérémy Sallé
- Institut Jacques Monod, CNRS, UMR 7592, University Paris Diderot, Sorbonne Paris Cité, 75205 Paris, France
| | - Marine Stefanutti
- Institut Jacques Monod, CNRS, UMR 7592, University Paris Diderot, Sorbonne Paris Cité, 75205 Paris, France
| | - Gilliane Maton
- Institut Jacques Monod, CNRS, UMR 7592, University Paris Diderot, Sorbonne Paris Cité, 75205 Paris, France
| | | | - Julie C Canman
- Columbia University Medical Center, Department of Pathology and Cell Biology, New York, NY 10032, USA
| | - Paul S Maddox
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Amy S Maddox
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Nicolas Minc
- Institut Jacques Monod, CNRS, UMR 7592, University Paris Diderot, Sorbonne Paris Cité, 75205 Paris, France
| | - François Nédélec
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, 69117 Heidelberg, Germany.
| | - Julien Dumont
- Institut Jacques Monod, CNRS, UMR 7592, University Paris Diderot, Sorbonne Paris Cité, 75205 Paris, France.
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Abstract
Microtubules act as "railways" for motor-driven intracellular transport, interact with accessory proteins to assemble into larger structures such as the mitotic spindle, and provide an organizational framework to the rest of the cell. Key to these functions is the fact that microtubules are "dynamic." As with actin, the polymer dynamics are driven by nucleotide hydrolysis and influenced by a host of specialized regulatory proteins, including microtubule-associated proteins. However, microtubule turnover involves a surprising behavior-termed dynamic instability-in which individual polymers switch stochastically between growth and depolymerization. Dynamic instability allows microtubules to explore intracellular space and remodel in response to intracellular and extracellular cues. Here, we review how such instability is central to the assembly of many microtubule-based structures and to the robust functioning of the microtubule cytoskeleton.
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Affiliation(s)
- Holly V Goodson
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556
| | - Erin M Jonasson
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556
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