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Bagdadi N, Wu J, Delaroche J, Serre L, Delphin C, De Andrade M, Carcel M, Nawabi H, Pinson B, Vérin C, Couté Y, Gory-Fauré S, Andrieux A, Stoppin-Mellet V, Arnal I. Stable GDP-tubulin islands rescue dynamic microtubules. J Cell Biol 2024; 223:e202307074. [PMID: 38758215 PMCID: PMC11101955 DOI: 10.1083/jcb.202307074] [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: 07/18/2023] [Revised: 02/26/2024] [Accepted: 05/04/2024] [Indexed: 05/18/2024] Open
Abstract
Microtubules are dynamic polymers that interconvert between phases of growth and shrinkage, yet they provide structural stability to cells. Growth involves hydrolysis of GTP-tubulin to GDP-tubulin, which releases energy that is stored within the microtubule lattice and destabilizes it; a GTP cap at microtubule ends is thought to prevent GDP subunits from rapidly dissociating and causing catastrophe. Here, using in vitro reconstitution assays, we show that GDP-tubulin, usually considered inactive, can itself assemble into microtubules, preferentially at the minus end, and promote persistent growth. GDP-tubulin-assembled microtubules are highly stable, displaying no detectable spontaneous shrinkage. Strikingly, islands of GDP-tubulin within dynamic microtubules stop shrinkage events and promote rescues. Microtubules thus possess an intrinsic capacity for stability, independent of accessory proteins. This finding provides novel mechanisms to explain microtubule dynamics.
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Affiliation(s)
- Nassiba Bagdadi
- Université Grenoble Alpes, INSERM, U1216, CNRS, CEA, Grenoble Institut Neurosciences (GIN), Grenoble, France
| | - Juliette Wu
- Université Grenoble Alpes, INSERM, U1216, CNRS, CEA, Grenoble Institut Neurosciences (GIN), Grenoble, France
| | - Julie Delaroche
- Université Grenoble Alpes, INSERM, U1216, CNRS, CEA, Grenoble Institut Neurosciences (GIN), Grenoble, France
| | - Laurence Serre
- Université Grenoble Alpes, INSERM, U1216, CNRS, CEA, Grenoble Institut Neurosciences (GIN), Grenoble, France
| | - Christian Delphin
- Université Grenoble Alpes, INSERM, U1216, CNRS, CEA, Grenoble Institut Neurosciences (GIN), Grenoble, France
| | - Manon De Andrade
- Université Grenoble Alpes, INSERM, U1216, CNRS, CEA, Grenoble Institut Neurosciences (GIN), Grenoble, France
| | - Marion Carcel
- Université Grenoble Alpes, INSERM, U1216, CNRS, CEA, Grenoble Institut Neurosciences (GIN), Grenoble, France
| | - Homaira Nawabi
- Université Grenoble Alpes, INSERM, U1216, CNRS, CEA, Grenoble Institut Neurosciences (GIN), Grenoble, France
| | - Benoît Pinson
- Metabolic Analyses Service, TBMCore—Université de Bordeaux—CNRS UAR 3427—INSERM US005, Bordeaux, France
| | - Claire Vérin
- Université Grenoble Alpes, INSERM, CEA, UA13 BGE, CNRS, FR2048, Grenoble, France
| | - Yohann Couté
- Université Grenoble Alpes, INSERM, CEA, UA13 BGE, CNRS, FR2048, Grenoble, France
| | - Sylvie Gory-Fauré
- Université Grenoble Alpes, INSERM, U1216, CNRS, CEA, Grenoble Institut Neurosciences (GIN), Grenoble, France
| | - Annie Andrieux
- Université Grenoble Alpes, INSERM, U1216, CNRS, CEA, Grenoble Institut Neurosciences (GIN), Grenoble, France
| | - Virginie Stoppin-Mellet
- Université Grenoble Alpes, INSERM, U1216, CNRS, CEA, Grenoble Institut Neurosciences (GIN), Grenoble, France
| | - Isabelle Arnal
- Université Grenoble Alpes, INSERM, U1216, CNRS, CEA, Grenoble Institut Neurosciences (GIN), Grenoble, France
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2
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Wang Z, Wang W, Liu S, Yang F, Liu X, Hua S, Zhu L, Xu A, Hill DL, Wang D, Jiang K, Lippincott-Schwartz J, Liu X, Yao X. CSPP1 stabilizes microtubules by capping both plus and minus ends. J Mol Cell Biol 2024; 16:mjae007. [PMID: 38389254 DOI: 10.1093/jmcb/mjae007] [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: 10/03/2023] [Revised: 12/11/2023] [Accepted: 02/21/2024] [Indexed: 02/24/2024] Open
Abstract
Although the dynamic instability of microtubules (MTs) is fundamental to many cellular functions, quiescent MTs with unattached free distal ends are commonly present and play important roles in various events to power cellular dynamics. However, how these free MT tips are stabilized remains poorly understood. Here, we report that centrosome and spindle pole protein 1 (CSPP1) caps and stabilizes both plus and minus ends of static MTs. Real-time imaging of laser-ablated MTs in live cells showed deposition of CSPP1 at the newly generated MT ends, whose dynamic instability was concomitantly suppressed. Consistently, MT ends in CSPP1-overexpressing cells were hyper-stabilized, while those in CSPP1-depleted cells were much more dynamic. This CSPP1-elicited stabilization of MTs was demonstrated to be achieved by suppressing intrinsic MT catastrophe and restricting polymerization. Importantly, CSPP1-bound MTs were resistant to mitotic centromere-associated kinesin-mediated depolymerization. These findings delineate a previously uncharacterized CSPP1 activity that integrates MT end capping to orchestrate quiescent MTs.
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Affiliation(s)
- Zhikai Wang
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, University of Science and Technology of China School of Life Sciences, Hefei 230027, China
- Anhui Key Laboratory for Cellular Dynamics and Chemical Biology, Hefei National Research Center for Interdisciplinary Sciences at the Microscale, Hefei 230027, China
| | - Wenwen Wang
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, University of Science and Technology of China School of Life Sciences, Hefei 230027, China
- Anhui Key Laboratory for Cellular Dynamics and Chemical Biology, Hefei National Research Center for Interdisciplinary Sciences at the Microscale, Hefei 230027, China
| | - Shuaiyu Liu
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, University of Science and Technology of China School of Life Sciences, Hefei 230027, China
- Anhui Key Laboratory for Cellular Dynamics and Chemical Biology, Hefei National Research Center for Interdisciplinary Sciences at the Microscale, Hefei 230027, China
| | - Fengrui Yang
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, University of Science and Technology of China School of Life Sciences, Hefei 230027, China
- Anhui Key Laboratory for Cellular Dynamics and Chemical Biology, Hefei National Research Center for Interdisciplinary Sciences at the Microscale, Hefei 230027, China
| | - Xu Liu
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, University of Science and Technology of China School of Life Sciences, Hefei 230027, China
- Anhui Key Laboratory for Cellular Dynamics and Chemical Biology, Hefei National Research Center for Interdisciplinary Sciences at the Microscale, Hefei 230027, China
| | - Shasha Hua
- Frontier Science Center for Immunology and Metabolism, Medical Research Institute, Wuhan University, Wuhan 430071, China
| | - Lijuan Zhu
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, University of Science and Technology of China School of Life Sciences, Hefei 230027, China
- Anhui Key Laboratory for Cellular Dynamics and Chemical Biology, Hefei National Research Center for Interdisciplinary Sciences at the Microscale, Hefei 230027, China
| | - Aoqing Xu
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, University of Science and Technology of China School of Life Sciences, Hefei 230027, China
- Anhui Key Laboratory for Cellular Dynamics and Chemical Biology, Hefei National Research Center for Interdisciplinary Sciences at the Microscale, Hefei 230027, China
| | - Donald L Hill
- Comprehensive Cancer Center, University of Alabama, Birmingham, AL 35233, USA
| | - Dongmei Wang
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, University of Science and Technology of China School of Life Sciences, Hefei 230027, China
- Anhui Key Laboratory for Cellular Dynamics and Chemical Biology, Hefei National Research Center for Interdisciplinary Sciences at the Microscale, Hefei 230027, China
| | - Kai Jiang
- Frontier Science Center for Immunology and Metabolism, Medical Research Institute, Wuhan University, Wuhan 430071, China
| | | | - Xing Liu
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, University of Science and Technology of China School of Life Sciences, Hefei 230027, China
- Anhui Key Laboratory for Cellular Dynamics and Chemical Biology, Hefei National Research Center for Interdisciplinary Sciences at the Microscale, Hefei 230027, China
| | - Xuebiao Yao
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, University of Science and Technology of China School of Life Sciences, Hefei 230027, China
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3
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Wei C, Zhang H, Fu M, Ye J, Yao B. Novel compound heterozygous variants in the CSPP1 gene causes Joubert syndrome: case report and literature review of the CSPP1 gene's pathogenic mechanism. Front Pediatr 2024; 12:1305754. [PMID: 38586154 PMCID: PMC10995352 DOI: 10.3389/fped.2024.1305754] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Accepted: 03/04/2024] [Indexed: 04/09/2024] Open
Abstract
Joubert syndrome (JS) is a rare autosomal recessive neurodevelopmental condition characterized by congenital mid-hindbrain abnormalities and a variety of clinical manifestations. This article describes a case of Joubert syndrome type 21 with microcephaly, seizures, developmental delay and language regression, caused by a CSPP1 gene variant and examines the contributing variables. This paper advances the understanding of JS by summarizing the literature and offering detection patterns for practitioners with clinical suspicions of JS.
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Affiliation(s)
| | | | | | - Jingping Ye
- Department of Pediatrics, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Baozhen Yao
- Department of Pediatrics, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
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Anisimov MN, Korshunova AV, Popov VV, Gudimchuk NB. Microtubule rescue control by drugs and MAPs examined with in vitro pedestal assay. Eur J Cell Biol 2023; 102:151366. [PMID: 37871345 DOI: 10.1016/j.ejcb.2023.151366] [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: 06/15/2023] [Revised: 10/11/2023] [Accepted: 10/16/2023] [Indexed: 10/25/2023] Open
Abstract
Microtubules are essential cytoskeletal polymers, which exhibit stochastic transitions between assembly and disassembly, known as catastrophes and rescues. Understanding of catastrophes, rescues, and their control by drugs and microtubule associated proteins (MAPs) has been informed by in vitro reconstitutions of microtubule dynamics. In such experiments microtubules are typically observed on a flat surface of the coverslip. In contrast, we have recently proposed a modified setup in which microtubules assemble from stabilized seeds, overhanging from microfabricated pedestals, so that their dynamic extensions are fully isolated from contact with the coverslip. This assay allows to eliminate potential artifacts, which may substantially affect the frequency of microtubule rescues in vitro. Here we use the pedestal assay to study the sensitivity of microtubules to paclitaxel, one of the best-known inhibitors of microtubule dynamics. By comparing observations in the conventional and the pedestal assays, we find that microtubule dynamics are substantially more sensitive to paclitaxel when the polymers can contact the coverslip. We interpret this as a consequence of the coverslip-induced microtubule assembly perturbation, leading to formation of lattice with defects, and thereby enhancing the efficiency of paclitaxel binding to microtubules in the conventional assay. To test this idea, we use vinblastine, another small-molecule inhibitor, which had been previously shown to cause microtubule growth perturbations. We find that in the pedestal assay vinblastine sensitizes microtubules to paclitaxel to the level, observed in the conventional assay. Interestingly, a minimal fragment of MAP called CLASP2, a previously characterized rescue factor, has a strong effect on microtubule rescues, regardless of the type of assay. Overall, our study underscores the role of microtubule damage in promoting rescues and highlights the utility of the in vitro pedestal assay to study microtubule dynamics modulation by tubulin inhibitors and MAPs.
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Affiliation(s)
- Mikhail N Anisimov
- Department of Physics, Lomonosov Moscow State University, Moscow, Russia; Center for theoretical problems of physicochemical pharmacology, Moscow, Russia
| | - Alena V Korshunova
- Department of Physics, Lomonosov Moscow State University, Moscow, Russia; Center for theoretical problems of physicochemical pharmacology, Moscow, Russia
| | - Vladimir V Popov
- Department of Physics, Lomonosov Moscow State University, Moscow, Russia
| | - Nikita B Gudimchuk
- Department of Physics, Lomonosov Moscow State University, Moscow, Russia; Center for theoretical problems of physicochemical pharmacology, Moscow, Russia.
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5
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Deretic J, Odabasi E, Firat-Karalar EN. The multifaceted roles of microtubule-associated proteins in the primary cilium and ciliopathies. J Cell Sci 2023; 136:jcs261148. [PMID: 38095645 DOI: 10.1242/jcs.261148] [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: 12/18/2023] Open
Abstract
The primary cilium is a conserved microtubule-based organelle that is critical for transducing developmental, sensory and homeostatic signaling pathways. It comprises an axoneme with nine parallel doublet microtubules extending from the basal body, surrounded by the ciliary membrane. The axoneme exhibits remarkable stability, serving as the skeleton of the cilium in order to maintain its shape and provide tracks to ciliary trafficking complexes. Although ciliary trafficking and signaling have been exhaustively characterized over the years, less is known about the unique structural and functional complexities of the axoneme. Recent work has yielded new insights into the mechanisms by which the axoneme is built with its proper length and architecture, particularly regarding the activity of microtubule-associated proteins (MAPs). In this Review, we first summarize current knowledge about the architecture, composition and specialized compartments of the primary cilium. Next, we discuss the mechanistic underpinnings of how a functional cilium is assembled, maintained and disassembled through the regulation of its axonemal microtubules. We conclude by examining the diverse localizations and functions of ciliary MAPs for the pathobiology of ciliary diseases.
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Affiliation(s)
- Jovana Deretic
- Department of Molecular Biology and Genetics, Koç University, Istanbul 34450, Turkey
| | - Ezgi Odabasi
- Department of Molecular Biology and Genetics, Koç University, Istanbul 34450, Turkey
| | - Elif Nur Firat-Karalar
- Department of Molecular Biology and Genetics, Koç University, Istanbul 34450, Turkey
- School of Medicine, Koç University, Istanbul 34450, Turkey
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6
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Romeiro Motta M, Biswas S, Schaedel L. Beyond uniformity: Exploring the heterogeneous and dynamic nature of the microtubule lattice. Eur J Cell Biol 2023; 102:151370. [PMID: 37922811 DOI: 10.1016/j.ejcb.2023.151370] [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: 08/14/2023] [Revised: 10/17/2023] [Accepted: 10/26/2023] [Indexed: 11/07/2023] Open
Abstract
A fair amount of research on microtubules since their discovery in 1963 has focused on their dynamic tips. In contrast, the microtubule lattice was long believed to be highly regular and static, and consequently received far less attention. Yet, as it turned out, the microtubule lattice is neither as regular, nor as static as previously believed: structural studies uncovered the remarkable wealth of different conformations the lattice can accommodate. In the last decade, the microtubule lattice was shown to be labile and to spontaneously undergo renovation, a phenomenon that is intimately linked to structural defects and was called "microtubule self-repair". Following this breakthrough discovery, further recent research provided a deeper understanding of the lattice self-repair mechanism, which we review here. Instrumental to these discoveries were in vitro microtubule reconstitution assays, in which microtubules are grown from the minimal components required for their dynamics. In this review, we propose a shift from the term "lattice self-repair" to "lattice dynamics", since this phenomenon is an inherent property of microtubules and can happen without microtubule damage. We focus on how in vitro microtubule reconstitution assays helped us learn (1) which types of structural variations microtubules display, (2) how these structural variations influence lattice dynamics and microtubule damage caused by mechanical stress, (3) how lattice dynamics impact tip dynamics, and (4) how microtubule-associated proteins (MAPs) can play a role in structuring the lattice. Finally, we discuss the unanswered questions about lattice dynamics and how technical advances will help us tackle these questions.
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Affiliation(s)
- Mariana Romeiro Motta
- Department of Physics, Center for Biophysics, Campus A2 4, Saarland University, 66123 Saarbrücken, Germany; Laboratoire Reproduction et Développement des Plantes, Université de Lyon, École normale supérieure de Lyon, Lyon 69364, France
| | - Subham Biswas
- Department of Physics, Center for Biophysics, Campus A2 4, Saarland University, 66123 Saarbrücken, Germany
| | - Laura Schaedel
- Department of Physics, Center for Biophysics, Campus A2 4, Saarland University, 66123 Saarbrücken, Germany.
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Duan D, Lyu W, Chai P, Ma S, Wu K, Wu C, Xiong Y, Sestan N, Zhang K, Koleske AJ. Abl2 repairs microtubules and phase separates with tubulin to promote microtubule nucleation. Curr Biol 2023; 33:4582-4598.e10. [PMID: 37858340 PMCID: PMC10877310 DOI: 10.1016/j.cub.2023.09.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2023] [Revised: 07/07/2023] [Accepted: 09/06/2023] [Indexed: 10/21/2023]
Abstract
Abl family kinases are evolutionarily conserved regulators of cell migration and morphogenesis. Genetic experiments in Drosophila suggest that Abl family kinases interact functionally with microtubules to regulate axon guidance and neuronal morphogenesis. Vertebrate Abl2 binds to microtubules and promotes their plus-end elongation, both in vitro and in cells, but the molecular mechanisms by which Abl2 regulates microtubule (MT) dynamics are unclear. We report here that Abl2 regulates MT assembly via condensation and direct interactions with both the MT lattice and tubulin dimers. We find that Abl2 promotes MT nucleation, which is further facilitated by the ability of the Abl2 C-terminal half to undergo liquid-liquid phase separation (LLPS) and form co-condensates with tubulin. Abl2 binds to regions adjacent to MT damage, facilitates MT repair via fresh tubulin recruitment, and increases MT rescue frequency and lifetime. Cryo-EM analyses strongly support a model in which Abl2 engages tubulin C-terminal tails along an extended MT lattice conformation at damage sites to facilitate repair via fresh tubulin recruitment. Abl2Δ688-790, which closely mimics a naturally occurring splice isoform, retains binding to the MT lattice but does not bind tubulin, promote MT nucleation, or increase rescue frequency. In COS-7 cells, MT reassembly after nocodazole treatment is greatly slowed in Abl2 knockout COS-7 cells compared with wild-type cells, and these defects are rescued by re-expression of Abl2, but not Abl2Δ688-790. We propose that Abl2 locally concentrates tubulin to promote MT nucleation and recruits it to defects in the MT lattice to enable repair and rescue.
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Affiliation(s)
- Daisy Duan
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06510, USA
| | - Wanqing Lyu
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06510, USA
| | - Pengxin Chai
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06510, USA
| | - Shaojie Ma
- Department of Neuroscience, Yale University, New Haven, CT 06510, USA
| | - Kuanlin Wu
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06510, USA
| | - Chunxiang Wu
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06510, USA
| | - Yong Xiong
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06510, USA
| | - Nenad Sestan
- Department of Neuroscience, Yale University, New Haven, CT 06510, USA; Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA; Department of Psychiatry, Yale School of Medicine, New Haven, CT 06510, USA; Department of Comparative Medicine, Yale School of Medicine, New Haven, CT 06510, USA; Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale School of Medicine, New Haven, CT 06510, USA; Yale Child Study Center, Yale School of Medicine, New Haven, CT 06510, USA
| | - Kai Zhang
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06510, USA
| | - Anthony J Koleske
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06510, USA; Department of Neuroscience, Yale University, New Haven, CT 06510, USA.
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Lawrence EJ, Chatterjee S, Zanic M. CLASPs stabilize the pre-catastrophe intermediate state between microtubule growth and shrinkage. J Cell Biol 2023; 222:e202107027. [PMID: 37184584 PMCID: PMC10195879 DOI: 10.1083/jcb.202107027] [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: 07/06/2021] [Revised: 12/03/2022] [Accepted: 04/18/2023] [Indexed: 05/16/2023] Open
Abstract
Cytoplasmic linker-associated proteins (CLASPs) regulate microtubules in fundamental cellular processes. CLASPs stabilize dynamic microtubules by suppressing microtubule catastrophe and promoting rescue, the switch-like transitions between growth and shrinkage. How CLASPs specifically modulate microtubule transitions is not understood. Here, we investigate the effects of CLASPs on the pre-catastrophe intermediate state of microtubule dynamics, employing distinct microtubule substrates to mimic the intermediate state. Surprisingly, we find that CLASP1 promotes the depolymerization of stabilized microtubules in the presence of GTP, but not in the absence of nucleotide. This activity is also observed for CLASP2 family members and a minimal TOG2-domain construct. Conversely, we find that CLASP1 stabilizes unstable microtubules upon tubulin dilution in the presence of GTP. Strikingly, our results reveal that CLASP1 drives microtubule substrates with vastly different inherent stabilities into the same slowly depolymerizing state in a nucleotide-dependent manner. We interpret this state as the pre-catastrophe intermediate state. Therefore, we conclude that CLASPs suppress microtubule catastrophe by stabilizing the intermediate state between growth and shrinkage.
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Affiliation(s)
- Elizabeth J. Lawrence
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN, USA
| | - Saptarshi Chatterjee
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN, USA
| | - Marija Zanic
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN, USA
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN, USA
- Department of Biochemistry, Vanderbilt University, Nashville, TN, USA
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