1
|
Chen GY, Deng C, Chenoweth DM, Lampson MA. The central spindle drives anaphase chromosome segregation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.30.610502. [PMID: 39257822 PMCID: PMC11383980 DOI: 10.1101/2024.08.30.610502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2024]
Abstract
Anaphase chromosome segregation depends on forces exerted by spindle microtubules. In the current model, forces on chromosomes are mediated through the spindle poles: sliding of antiparallel microtubules in the central spindle pushes poles apart, while kinetochore microtubule (kMT) depolymerization pulls chromosomes towards the poles. Here we show that the central spindle is directly linked to the chromosomes rather than the poles in anaphase, based on three lines of evidence. Chromosomes in monopolar spindles can move away from the pole, consistent with forces exerted by antiparallel microtubule sliding. In bipolar spindles, kMT depolymerization is constrained by suppressing central spindle sliding, indicating kinetochore linkage to the central spindle. Finally, increasing the rate of kMT depolymerization slows pole separation without increasing chromosome separation velocity. We conclude that central spindle sliding drives anaphase chromosome separation, while kMT depolymerization limits spindle elongation.
Collapse
|
2
|
Zimyanin V, Redemann S. Microtubule length correlates with spindle length in C. elegans meiosis. Cytoskeleton (Hoboken) 2024; 81:356-368. [PMID: 38450962 PMCID: PMC11333180 DOI: 10.1002/cm.21849] [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: 11/23/2023] [Revised: 01/24/2024] [Accepted: 02/21/2024] [Indexed: 03/08/2024]
Abstract
The accurate segregation of chromosomes during female meiosis relies on the precise assembly and function of the meiotic spindle, a dynamic structure primarily composed of microtubules. Despite the crucial role of microtubule dynamics in this process, the relationship between microtubule length and spindle size remains elusive. Leveraging Caenorhabditis elegans as a model system, we combined electron tomography and live imaging to investigate this correlation. Our analysis revealed significant changes in spindle length throughout meiosis, coupled with alterations in microtubule length. Surprisingly, while spindle size decreases during the initial stages of anaphase, the size of antiparallel microtubule overlap decreased as well. Detailed electron tomography shows a positive correlation between microtubule length and spindle size, indicating a role of microtubule length in determining spindle dimensions. Notably, microtubule numbers displayed no significant association with spindle length, highlighting the dominance of microtubule length regulation in spindle size determination. Depletion of the microtubule depolymerase KLP-7 led to elongated metaphase spindles with increased microtubule length, supporting the link between microtubule length and spindle size. These findings underscore the pivotal role of regulating microtubule dynamics, and thus microtubule length, in governing spindle rearrangements during meiotic division, shedding light on fundamental mechanisms dictating spindle architecture.
Collapse
Affiliation(s)
- Vitaly Zimyanin
- Department of Molecular Physiology and Biological Physics, University of Virginia, School of Medicine, Charlottesville, VA, USA
- Center for Membrane and Cell Physiology, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Stefanie Redemann
- Department of Molecular Physiology and Biological Physics, University of Virginia, School of Medicine, Charlottesville, VA, USA
- Center for Membrane and Cell Physiology, University of Virginia School of Medicine, Charlottesville, VA, USA
- Department of Cell Biology, University of Virginia School of Medicine, Charlottesville, VA, USA
| |
Collapse
|
3
|
Xie P. Modeling study of kinesin-13 MCAK microtubule depolymerase. EUROPEAN BIOPHYSICS JOURNAL : EBJ 2024; 53:339-354. [PMID: 39093405 DOI: 10.1007/s00249-024-01718-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2024] [Accepted: 07/18/2024] [Indexed: 08/04/2024]
Abstract
Mitotic centromere-associated kinesin (MCAK) motor protein is a typical member of the kinesin-13 family, which can depolymerize microtubules from both plus and minus ends. A critical issue for the MCAK motor is how it performs the depolymerase activity. To address the issue, the pathway of the MCAK motor moving on microtubules and depolymerizing the microtubules is presented here. On the basis of the pathway, the dynamics of both the wild-type and mutant MCAK motors is studied theoretically, which include the full-length MCAK, the full-length MCAK with mutations in the α4-helix of the motor domain, the mutant full-length MCAK with a neutralized neck, the monomeric MCAK and the mutant monomeric MCAK with a neutralized neck. The studies show that a single dimeric MCAK motor can depolymerize microtubules in a processive manner, with either one tubulin or two tubulins being removed per times. The theoretical results are in agreement with the available experimental data. Moreover, predicted results are provided.
Collapse
Affiliation(s)
- Ping Xie
- Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China.
| |
Collapse
|
4
|
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.
Collapse
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
| |
Collapse
|
5
|
Perez-Bertoldi JM, Zhao Y, Thawani A, Yildiz A, Nogales E. Molecular interplay between HURP and Kif18A in mitotic spindle regulation. RESEARCH SQUARE 2024:rs.3.rs-4249615. [PMID: 38854046 PMCID: PMC11160874 DOI: 10.21203/rs.3.rs-4249615/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
During mitosis, microtubule dynamics are regulated to ensure proper alignment and segregation of chromosomes. The dynamics of kinetochore-attached microtubules are regulated by hepatoma-upregulated protein (HURP) and the mitotic kinesin-8 Kif18A, but the underlying mechanism remains elusive. Using single-molecule imaging in vitro, we demonstrate that Kif18A motility is regulated by HURP. While sparse decoration of HURP activates the motor, higher concentrations hinder processive motility. To shed light on this behavior, we determined the binding mode of HURP to microtubules using Cryo-EM. The structure reveals that one HURP motif spans laterally across β-tubulin, while a second motif binds between adjacent protofilaments. HURP partially overlaps with the microtubule-binding site of the Kif18A motor domain, indicating that excess HURP inhibits Kif18A motility by steric exclusion. We also observed that HURP and Kif18A function together to suppress dynamics of the microtubule plus-end, providing a mechanistic basis for how they collectively serve in spindle length control.
Collapse
Affiliation(s)
| | - Yuanchang Zhao
- Physics Department, University of California, Berkeley, CA, USA
| | - Akanksha Thawani
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
| | - Ahmet Yildiz
- Biophysics Graduate Group, University of California, Berkeley, CA, USA
- Physics Department, University of California, Berkeley, CA, USA
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
- Molecular Biophysics and Integrative Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Eva Nogales
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
- Molecular Biophysics and Integrative Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Howard Hughes Medical Institute, University of California, Berkeley, CA, USA
| |
Collapse
|
6
|
Zhu H, Bao Y, Dou X, Zuo X, Ye J, Ma H, Bu Y, Wang Y, Zhu J. KIF2C is a critical regulator for malignant progression of head and neck squamous cell carcinoma. Am J Cancer Res 2024; 14:2538-2554. [PMID: 38859848 PMCID: PMC11162673 DOI: 10.62347/cibm2965] [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: 01/21/2024] [Accepted: 05/08/2024] [Indexed: 06/12/2024] Open
Abstract
Head and neck squamous cell carcinoma (HNSCC) is a significant cause of mortality, while the underlying mechanism remains unclear. Our studies have revealed that KIF2C plays a crucial role in tumor proliferation and metastasis in HNSCC. The results demonstrate that KIF2C is highly expressed at both the mRNA and protein levels and is closely associated with lymph node metastasis. The gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses indicate that the differentially expressed genes are enriched in processes or pathways related to cell adhesion and cell mitosis in HNSCC. Moreover, the established protein-protein interaction network identifies KIF2C as a potential hub gene in HNSCC. Knockdown of KIF2C has been demonstrated to significantly reduce cell migration and invasion ability, leading to cell cycle arrest, a high proportion of abnormal cell apoptosis, and cell chromosome division mismatches in the HNSCC cell line. Downstream genes such as PDGFA, EGFR, TP63, SNAI2, KRT5, and KRT14 were found to be down-regulated, and multiple critical pathways, including mTOR, ERK, and PI3K-AKT pathways, were inactivated as a result of KIF2C knockdown. These findings provide strong evidence for the crucial role of KIF2C in HNSCC and suggest that targeting KIF2C may be a promising therapeutic strategy for this disease. Knockdown of KIF2C has been shown to significantly inhibit tumor proliferation in nude mice, demonstrating the potential therapeutic role of KIF2C in HNSCC treatment.
Collapse
Affiliation(s)
- Haiyue Zhu
- Department of Otolaryngology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Medical UniversityChongqing 400016, P. R. China
- Department of Biochemistry and Molecular Biology, College of Basic Medical Sciences, Chongqing Medical UniversityChongqing 400016, P. R. China
- Molecular Medicine and Cancer Research Center, Chongqing Medical UniversityChongqing 400016, P. R. China
| | - Yuxin Bao
- Department of Otolaryngology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Medical UniversityChongqing 400016, P. R. China
- Department of Biochemistry and Molecular Biology, College of Basic Medical Sciences, Chongqing Medical UniversityChongqing 400016, P. R. China
- Molecular Medicine and Cancer Research Center, Chongqing Medical UniversityChongqing 400016, P. R. China
| | - Xuanqi Dou
- Department of Biochemistry and Molecular Biology, College of Basic Medical Sciences, Chongqing Medical UniversityChongqing 400016, P. R. China
- Molecular Medicine and Cancer Research Center, Chongqing Medical UniversityChongqing 400016, P. R. China
| | - Xiaofeng Zuo
- Department of Biochemistry and Molecular Biology, College of Basic Medical Sciences, Chongqing Medical UniversityChongqing 400016, P. R. China
- Molecular Medicine and Cancer Research Center, Chongqing Medical UniversityChongqing 400016, P. R. China
| | - Junhong Ye
- Department of Biochemistry and Molecular Biology, College of Basic Medical Sciences, Chongqing Medical UniversityChongqing 400016, P. R. China
- Molecular Medicine and Cancer Research Center, Chongqing Medical UniversityChongqing 400016, P. R. China
| | - Haiyu Ma
- Department of Otolaryngology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Medical UniversityChongqing 400016, P. R. China
- Department of Biochemistry and Molecular Biology, College of Basic Medical Sciences, Chongqing Medical UniversityChongqing 400016, P. R. China
- Molecular Medicine and Cancer Research Center, Chongqing Medical UniversityChongqing 400016, P. R. China
| | - Youquan Bu
- Department of Biochemistry and Molecular Biology, College of Basic Medical Sciences, Chongqing Medical UniversityChongqing 400016, P. R. China
- Molecular Medicine and Cancer Research Center, Chongqing Medical UniversityChongqing 400016, P. R. China
| | - Yitao Wang
- Department of Biochemistry and Molecular Biology, College of Basic Medical Sciences, Chongqing Medical UniversityChongqing 400016, P. R. China
- Molecular Medicine and Cancer Research Center, Chongqing Medical UniversityChongqing 400016, P. R. China
| | - Jiang Zhu
- Department of Otolaryngology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Medical UniversityChongqing 400016, P. R. China
- Molecular Medicine and Cancer Research Center, Chongqing Medical UniversityChongqing 400016, P. R. China
| |
Collapse
|
7
|
Tell I Puig A, Soldati-Favre D. Roles of the tubulin-based cytoskeleton in the Toxoplasma gondii apical complex. Trends Parasitol 2024; 40:401-415. [PMID: 38531711 DOI: 10.1016/j.pt.2024.02.010] [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: 01/08/2024] [Revised: 02/26/2024] [Accepted: 02/28/2024] [Indexed: 03/28/2024]
Abstract
Microtubules (MTs) play a vital role as key components of the eukaryotic cytoskeleton. The phylum Apicomplexa comprises eukaryotic unicellular parasitic organisms defined by the presence of an apical complex which consists of specialized secretory organelles and tubulin-based cytoskeletal elements. One apicomplexan parasite, Toxoplasma gondii, is an omnipresent opportunistic pathogen with significant medical and veterinary implications. To ensure successful infection and widespread dissemination, T. gondii heavily relies on the tubulin structures present in the apical complex. Recent advances in high-resolution imaging, coupled with reverse genetics, have offered deeper insights into the composition, functionality, and dynamics of these tubulin-based structures. The apicomplexan tubulins differ from those of their mammalian hosts, endowing them with unique attributes and susceptibility to specific classes of inhibitory compounds.
Collapse
Affiliation(s)
- Albert Tell I Puig
- Department of Microbiology and Molecular Medicine, CMU, University of Geneva, Geneva, Switzerland.
| | - Dominique Soldati-Favre
- Department of Microbiology and Molecular Medicine, CMU, University of Geneva, Geneva, Switzerland
| |
Collapse
|
8
|
Perez-Bertoldi JM, Zhao Y, Thawani A, Yildiz A, Nogales E. Molecular interplay between HURP and Kif18A in mitotic spindle regulation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.11.589088. [PMID: 38645125 PMCID: PMC11030443 DOI: 10.1101/2024.04.11.589088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
During mitosis, microtubule dynamics are regulated to ensure proper alignment and segregation of chromosomes. The dynamics of kinetochore-attached microtubules are regulated by hepatoma-upregulated protein (HURP) and the mitotic kinesin-8 Kif18A, but the underlying mechanism remains elusive. Using single-molecule imaging in vitro , we demonstrate that Kif18A motility is regulated by HURP. While sparse decoration of HURP activates the motor, higher concentrations hinder processive motility. To shed light on this behavior, we determined the binding mode of HURP to microtubules using Cryo-EM. The structure reveals that one HURP motif spans laterally across β-tubulin, while a second motif binds between adjacent protofilaments. HURP partially overlaps with the microtubule-binding site of the Kif18A motor domain, indicating that excess HURP inhibits Kif18A motility by steric exclusion. We also observed that HURP and Kif18A function together to suppress dynamics of the microtubule plus-end, providing a mechanistic basis for how they collectively serve in spindle length control.
Collapse
|
9
|
Kucharski TJ, Vlasac IM, Higgs MR, Christensen BC, Bechstedt S, Compton DA. An Aurora kinase A-BOD1L1-PP2A B56 Axis promotes chromosome segregation fidelity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.08.06.552174. [PMID: 37609141 PMCID: PMC10441337 DOI: 10.1101/2023.08.06.552174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/24/2023]
Abstract
Cancer cells are often aneuploid and frequently display elevated rates of chromosome missegregation in a phenomenon called chromosomal instability (CIN). CIN is commonly caused by hyperstable kinetochore-microtubule (K-MT) attachments that reduces the efficiency of correction of erroneous K-MT attachments. We recently showed that UMK57, a chemical agonist of MCAK (alias KIF2C) improves chromosome segregation fidelity in CIN cancer cells although cells rapidly develop adaptive resistance. To determine the mechanism of resistance we performed unbiased proteomic screens which revealed increased phosphorylation in cells adapted to UMK57 at two Aurora kinase A phosphoacceptor sites on BOD1L1 (alias FAM44A). BOD1L1 depletion or Aurora kinase A inhibition eliminated resistance to UMK57 in CIN cancer cells. BOD1L1 localizes to spindles/kinetochores during mitosis, interacts with the PP2A phosphatase, and regulates phosphorylation levels of kinetochore proteins, chromosome alignment, mitotic progression and fidelity. Moreover, the BOD1L1 gene is mutated in a subset of human cancers, and BOD1L1 depletion reduces cell growth in combination with clinically relevant doses of taxol or Aurora kinase A inhibitor. Thus, an Aurora kinase A -BOD1L1-PP2A axis promotes faithful chromosome segregation during mitosis.
Collapse
Affiliation(s)
- Thomas J. Kucharski
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth
- Department of Anatomy and Cell Biology, McGill University, Montréal, Canada, H3A 0C7
| | - Irma M. Vlasac
- Department of Epidemiology, Geisel School of Medicine at Dartmouth
| | - Martin R. Higgs
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Brock C. Christensen
- Department of Epidemiology, Geisel School of Medicine at Dartmouth
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth
- Department of Community and Family Medicine, Geisel School of Medicine at Dartmouth
- Dartmouth Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH
| | - Susanne Bechstedt
- Department of Anatomy and Cell Biology, McGill University, Montréal, Canada, H3A 0C7
| | - Duane A. Compton
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth
- Department of Community and Family Medicine, Geisel School of Medicine at Dartmouth
| |
Collapse
|
10
|
Carrington G, Fatima U, Caramujo I, Lewis T, Casas-Mao D, Peckham M. A multiscale approach reveals the molecular architecture of the autoinhibited kinesin KIF5A. J Biol Chem 2024; 300:105713. [PMID: 38309508 PMCID: PMC10907169 DOI: 10.1016/j.jbc.2024.105713] [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: 11/06/2023] [Revised: 01/23/2024] [Accepted: 01/26/2024] [Indexed: 02/05/2024] Open
Abstract
Kinesin-1 is a microtubule motor that transports cellular cargo along microtubules. KIF5A is one of three kinesin-1 isoforms in humans, all of which are autoinhibited by an interaction between the motor and an IAK motif in the proximal region of the C-terminal tail. The C-terminal tail of KIF5A is ∼80 residues longer than the other two kinesin-1 isoforms (KIF5B and KIF5C) and it is unclear if it contributes to autoinhibition. Mutations in KIF5A cause neuronal diseases and could affect autoinhibition, as reported for a mutation that skips exon 27, altering its C-terminal sequence. Here, we combined negative-stain electron microscopy, crosslinking mass spectrometry (XL-MS) and AlphaFold2 structure prediction to determine the molecular architecture of the full-length autoinhibited KIF5A homodimer, in the absence of light chains. We show that KIF5A forms a compact, bent conformation, through a bend between coiled-coils 2 and 3, around P687. XL-MS of WT KIF5A revealed extensive interactions between residues in the motor, between coiled-coil 1 and the motor, between coiled-coils 1 and 2, with coiled-coils 3 and 4, and the proximal region of the C-terminal tail and the motor in the autoinhibited state, but not between the distal C-terminal region and the rest of the molecule. While negative-stain electron microscopy of exon-27 KIF5A splice mutant showed the presence of autoinhibited molecules, XL-MS analysis suggested that its autoinhibited state is more labile. Our model offers a conceptual framework for understanding how mutations within the motor and stalk domain may affect motor activity.
Collapse
Affiliation(s)
- Glenn Carrington
- Faculty of Biological Sciences, Astbury Centre for Structural Biology and the School of Molecular and Cellular Biology, University of Leeds, Leeds, UK
| | - Uzrama Fatima
- Faculty of Biological Sciences, Astbury Centre for Structural Biology and the School of Molecular and Cellular Biology, University of Leeds, Leeds, UK
| | - Ines Caramujo
- Faculty of Biological Sciences, Astbury Centre for Structural Biology and the School of Molecular and Cellular Biology, University of Leeds, Leeds, UK
| | - Tarek Lewis
- Faculty of Biological Sciences, Astbury Centre for Structural Biology and the School of Molecular and Cellular Biology, University of Leeds, Leeds, UK
| | - David Casas-Mao
- Faculty of Biological Sciences, Astbury Centre for Structural Biology and the School of Molecular and Cellular Biology, University of Leeds, Leeds, UK
| | - Michelle Peckham
- Faculty of Biological Sciences, Astbury Centre for Structural Biology and the School of Molecular and Cellular Biology, University of Leeds, Leeds, UK.
| |
Collapse
|
11
|
Xie P. A model of microtubule depolymerization by kinesin-8 motor proteins. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2023; 141:87-122. [PMID: 38960488 DOI: 10.1016/bs.apcsb.2023.12.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/05/2024]
Abstract
The dimeric kinesin-8 motors have the biological function of depolymerizing microtubules (MTs) from the plus end. However, the molecular mechanism of the depolymerization promoted by the kinesin-8 motors is still undetermined. Here, a model is proposed for the MT depolymerization by the kinesin-8 motors. Based on the model, the dynamics of depolymerization in the presence of the single motor at the MT plus end under no load and under load on the motor is studied theoretically. The dynamics of depolymerization in the presence of multiple motors at the MT plus end is also analyzed. The theoretical results explain well the available experimental data. The studies can also be applicable to other families of kinesin motors such as kinesin-13 mitotic centromere-associated kinesin motors that have the ability to depolymerize MTs.
Collapse
Affiliation(s)
- Ping Xie
- Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Science, Beijing, P.R. China.
| |
Collapse
|
12
|
Lawrence EJ, Chatterjee S, Zanic M. More is different: Reconstituting complexity in microtubule regulation. J Biol Chem 2023; 299:105398. [PMID: 37898404 PMCID: PMC10694663 DOI: 10.1016/j.jbc.2023.105398] [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: 06/11/2023] [Revised: 10/13/2023] [Accepted: 10/18/2023] [Indexed: 10/30/2023] Open
Abstract
Microtubules are dynamic cytoskeletal filaments that undergo stochastic switching between phases of polymerization and depolymerization-a behavior known as dynamic instability. Many important cellular processes, including cell motility, chromosome segregation, and intracellular transport, require complex spatiotemporal regulation of microtubule dynamics. This coordinated regulation is achieved through the interactions of numerous microtubule-associated proteins (MAPs) with microtubule ends and lattices. Here, we review the recent advances in our understanding of microtubule regulation, focusing on results arising from biochemical in vitro reconstitution approaches using purified multiprotein ensembles. We discuss how the combinatory effects of MAPs affect both the dynamics of individual microtubule ends, as well as the stability and turnover of the microtubule lattice. In addition, we highlight new results demonstrating the roles of protein condensates in microtubule regulation. Our overall intent is to showcase how lessons learned from reconstitution approaches help unravel the regulatory mechanisms at play in complex cellular environments.
Collapse
Affiliation(s)
- Elizabeth J Lawrence
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee, USA
| | - Saptarshi Chatterjee
- 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 Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, Tennessee, USA; Department of Biochemistry, Vanderbilt University, Nashville, Tennessee, USA.
| |
Collapse
|
13
|
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.
Collapse
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
| |
Collapse
|
14
|
Rodrigues-Ferreira S, Morin M, Guichaoua G, Moindjie H, Haykal MM, Collier O, Stoven V, Nahmias C. A Network of 17 Microtubule-Related Genes Highlights Functional Deregulations in Breast Cancer. Cancers (Basel) 2023; 15:4870. [PMID: 37835564 PMCID: PMC10571893 DOI: 10.3390/cancers15194870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 09/29/2023] [Accepted: 10/04/2023] [Indexed: 10/15/2023] Open
Abstract
A wide panel of microtubule-associated proteins and kinases is involved in coordinated regulation of the microtubule cytoskeleton and may thus represent valuable molecular markers contributing to major cellular pathways deregulated in cancer. We previously identified a panel of 17 microtubule-related (MT-Rel) genes that are differentially expressed in breast tumors showing resistance to taxane-based chemotherapy. In the present study, we evaluated the expression, prognostic value and functional impact of these genes in breast cancer. We show that 14 MT-Rel genes (KIF4A, ASPM, KIF20A, KIF14, TPX2, KIF18B, KIFC1, AURKB, KIF2C, GTSE1, KIF15, KIF11, RACGAP1, STMN1) are up-regulated in breast tumors compared with adjacent normal tissue. Six of them (KIF4A, ASPM, KIF20A, KIF14, TPX2, KIF18B) are overexpressed by more than 10-fold in tumor samples and four of them (KIF11, AURKB, TPX2 and KIFC1) are essential for cell survival. Overexpression of all 14 genes, and underexpression of 3 other MT-Rel genes (MAST4, MAPT and MTUS1) are associated with poor breast cancer patient survival. A Systems Biology approach highlighted three major functional networks connecting the 17 MT-Rel genes and their partners, which are centered on spindle assembly, chromosome segregation and cytokinesis. Our studies identified mitotic Aurora kinases and their substrates as major targets for therapeutic approaches against breast cancer.
Collapse
Affiliation(s)
- Sylvie Rodrigues-Ferreira
- Gustave Roussy Cancer Center, F-94800 Villejuif, France; (S.R.-F.); (M.M.); (H.M.); (M.M.H.)
- INSERM U981, Université Paris-Saclay, F-94800 Villejuif, France
- Inovarion, F-75005 Paris, France
| | - Morgane Morin
- Gustave Roussy Cancer Center, F-94800 Villejuif, France; (S.R.-F.); (M.M.); (H.M.); (M.M.H.)
- INSERM U981, Université Paris-Saclay, F-94800 Villejuif, France
| | - Gwenn Guichaoua
- CBIO (Centre de Bioinformatique), Mines Paris-PSL, PSL Research University, F-75005 Paris, France;
- INSERM U900, Institut Curie, F-75005 Paris, France
| | - Hadia Moindjie
- Gustave Roussy Cancer Center, F-94800 Villejuif, France; (S.R.-F.); (M.M.); (H.M.); (M.M.H.)
- INSERM U981, Université Paris-Saclay, F-94800 Villejuif, France
| | - Maria M. Haykal
- Gustave Roussy Cancer Center, F-94800 Villejuif, France; (S.R.-F.); (M.M.); (H.M.); (M.M.H.)
- INSERM U981, Université Paris-Saclay, F-94800 Villejuif, France
| | - Olivier Collier
- MODAL’X, UPL, Université Paris Nanterre, CNRS, F-92000 Nanterre, France;
| | - Véronique Stoven
- CBIO (Centre de Bioinformatique), Mines Paris-PSL, PSL Research University, F-75005 Paris, France;
- INSERM U900, Institut Curie, F-75005 Paris, France
| | - Clara Nahmias
- Gustave Roussy Cancer Center, F-94800 Villejuif, France; (S.R.-F.); (M.M.); (H.M.); (M.M.H.)
- INSERM U981, Université Paris-Saclay, F-94800 Villejuif, France
| |
Collapse
|
15
|
Eren E, Watts NR, Randazzo D, Palmer I, Sackett DL, Wingfield PT. Structural basis of microtubule depolymerization by the kinesin-like activity of HIV-1 Rev. Structure 2023; 31:1233-1246.e5. [PMID: 37572662 PMCID: PMC10592302 DOI: 10.1016/j.str.2023.07.009] [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: 08/17/2022] [Revised: 04/07/2023] [Accepted: 07/18/2023] [Indexed: 08/14/2023]
Abstract
HIV-1 Rev is an essential regulatory protein that transports unspliced and partially spliced viral mRNAs from the nucleus to the cytoplasm for the expression of viral structural proteins. During its nucleocytoplasmic shuttling, Rev interacts with several host proteins to use the cellular machinery for the advantage of the virus. Here, we report the 3.5 Å cryo-EM structure of a 4.8 MDa Rev-tubulin ring complex. Our structure shows that Rev's arginine-rich motif (ARM) binds to both the acidic surfaces and the C-terminal tails of α/β-tubulin. The Rev-tubulin interaction is functionally homologous to that of kinesin-13, potently destabilizing microtubules at sub-stoichiometric levels. Expression of Rev in astrocytes and HeLa cells shows that it can modulate the microtubule cytoskeleton within the cellular environment. These results show a previously undefined regulatory role of Rev.
Collapse
Affiliation(s)
- Elif Eren
- Protein Expression Laboratory, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Norman R Watts
- Protein Expression Laboratory, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Davide Randazzo
- Light Imaging Section, Office of Science and Technology, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Ira Palmer
- Protein Expression Laboratory, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Dan L Sackett
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Paul T Wingfield
- Protein Expression Laboratory, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
| |
Collapse
|
16
|
Henkin G, Brito C, Thomas C, Surrey T. The minus-end depolymerase KIF2A drives flux-like treadmilling of γTuRC-uncapped microtubules. J Cell Biol 2023; 222:e202304020. [PMID: 37615667 PMCID: PMC10450741 DOI: 10.1083/jcb.202304020] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 07/27/2023] [Accepted: 08/04/2023] [Indexed: 08/25/2023] Open
Abstract
During mitosis, microtubules in the spindle turn over continuously. At spindle poles, where microtubule minus ends are concentrated, microtubule nucleation and depolymerization, the latter required for poleward microtubule flux, happen side by side. How these seemingly antagonistic processes of nucleation and depolymerization are coordinated is not understood. Here, we reconstitute this coordination in vitro combining different pole-localized activities. We find that the spindle pole-localized kinesin-13 KIF2A is a microtubule minus-end depolymerase, in contrast to its paralog MCAK. Due to its asymmetric activity, KIF2A still allows microtubule nucleation from the γ-tubulin ring complex (γTuRC), which serves as a protective cap shielding the minus end against KIF2A binding. Efficient γTuRC uncapping requires the combined action of KIF2A and a microtubule severing enzyme, leading to treadmilling of the uncapped microtubule driven by KIF2A. Together, these results provide insight into the molecular mechanisms by which a minimal protein module coordinates microtubule nucleation and depolymerization at spindle poles consistent with their role in poleward microtubule flux.
Collapse
Affiliation(s)
- Gil Henkin
- Centre for Genomic Regulation(CRG), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - Cláudia Brito
- Centre for Genomic Regulation(CRG), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | | | - Thomas Surrey
- Centre for Genomic Regulation(CRG), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
- ICREA, Barcelona, Spain
| |
Collapse
|
17
|
Chen X, Portran D, Widmer LA, Stangier MM, Czub MP, Liakopoulos D, Stelling J, Steinmetz MO, Barral Y. The motor domain of the kinesin Kip2 promotes microtubule polymerization at microtubule tips. J Cell Biol 2023; 222:214052. [PMID: 37093124 PMCID: PMC10130750 DOI: 10.1083/jcb.202110126] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 01/01/2023] [Accepted: 03/22/2023] [Indexed: 04/25/2023] Open
Abstract
Kinesins are microtubule-dependent motor proteins, some of which moonlight as microtubule polymerases, such as the yeast protein Kip2. Here, we show that the CLIP-170 ortholog Bik1 stabilizes Kip2 at microtubule ends where the motor domain of Kip2 promotes microtubule polymerization. Live-cell imaging and mathematical estimation of Kip2 dynamics reveal that disrupting the Kip2-Bik1 interaction aborts Kip2 dwelling at microtubule ends and abrogates its microtubule polymerization activity. Structural modeling and biochemical experiments identify a patch of positively charged residues that enables the motor domain to bind free tubulin dimers alternatively to the microtubule shaft. Neutralizing this patch abolished the ability of Kip2 to promote microtubule growth both in vivo and in vitro without affecting its ability to walk along microtubules. Our studies suggest that Kip2 utilizes Bik1 as a cofactor to track microtubule tips, where its motor domain then recruits free tubulin and catalyzes microtubule assembly.
Collapse
Affiliation(s)
- Xiuzhen Chen
- Institute of Biochemistry, Eidgenössische Technische Hochschule Zürich , Zurich, Switzerland
| | - Didier Portran
- CRBM, Université de Montpellier , CNRS, Montpellier, France
| | - Lukas A Widmer
- Department of Biosystems Science and Engineering, Eidgenössische Technische Hochschule Zürich, and Swiss Institute of Bioinformatics, Basel, Switzerland
| | - Marcel M Stangier
- Department of Biology and Chemistry, Laboratory of Biomolecular Research, Paul Scherrer Institute, Villigen, Switzerland
| | - Mateusz P Czub
- Department of Biology and Chemistry, Laboratory of Biomolecular Research, Paul Scherrer Institute, Villigen, Switzerland
| | - Dimitris Liakopoulos
- CRBM, Université de Montpellier , CNRS, Montpellier, France
- Laboratory of Biology, University of Ioannina, Faculty of Medicine, Ioannina, Greece
| | - Jörg Stelling
- Department of Biosystems Science and Engineering, Eidgenössische Technische Hochschule Zürich, and Swiss Institute of Bioinformatics, Basel, Switzerland
| | - Michel O Steinmetz
- Department of Biology and Chemistry, Laboratory of Biomolecular Research, Paul Scherrer Institute, Villigen, Switzerland
- University of Basel, Biozentrum , Basel, Switzerland
| | - Yves Barral
- Institute of Biochemistry, Eidgenössische Technische Hochschule Zürich , Zurich, Switzerland
| |
Collapse
|
18
|
Fu G, Yan S, Khoo CJ, Chao VC, Liu Z, Mukhi M, Hervas R, Li XD, Ti SC. Integrated regulation of tubulin tyrosination and microtubule stability by human α-tubulin isotypes. Cell Rep 2023; 42:112653. [PMID: 37379209 DOI: 10.1016/j.celrep.2023.112653] [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: 07/28/2022] [Revised: 05/03/2023] [Accepted: 05/31/2023] [Indexed: 06/30/2023] Open
Abstract
Tubulin isotypes are critical for the functions of cellular microtubules, which exhibit different stability and harbor various post-translational modifications. However, how tubulin isotypes determine the activities of regulators for microtubule stability and modifications remains unknown. Here, we show that human α4A-tubulin, a conserved genetically detyrosinated α-tubulin isotype, is a poor substrate for enzymatic tyrosination. To examine the stability of microtubules reconstituted with defined tubulin compositions, we develop a strategy to site-specifically label recombinant human tubulin for single-molecule TIRF microscopy-based in vitro assays. The incorporation of α4A-tubulin into the microtubule lattice stabilizes the polymers from passive and MCAK-stimulated depolymerization. Further characterization reveals that the compositions of α-tubulin isotypes and tyrosination/detyrosination states allow graded control for the microtubule binding and the depolymerization activities of MCAK. Together, our results uncover the tubulin isotype-dependent enzyme activity for an integrated regulation of α-tubulin tyrosination/detyrosination states and microtubule stability, two well-correlated features of cellular microtubules.
Collapse
Affiliation(s)
- Guoling Fu
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong SAR, China
| | - Shan Yan
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong SAR, China
| | - Chen Jing Khoo
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong SAR, China
| | - Victor C Chao
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong SAR, China
| | - Zheng Liu
- Department of Chemistry, The University of Hong Kong, Hong Kong SAR, China
| | - Mayur Mukhi
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong SAR, China
| | - Rubén Hervas
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong SAR, China
| | - Xiang David Li
- Department of Chemistry, The University of Hong Kong, Hong Kong SAR, China
| | - Shih-Chieh Ti
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong SAR, China.
| |
Collapse
|
19
|
Smith JC, Husted S, Pilrose J, Ems-McClung SC, Stout JR, Carpenter RL, Walczak CE. MCAK Inhibitors Induce Aneuploidy in Triple-Negative Breast Cancer Models. Cancers (Basel) 2023; 15:3309. [PMID: 37444419 PMCID: PMC10340532 DOI: 10.3390/cancers15133309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 06/16/2023] [Accepted: 06/19/2023] [Indexed: 07/15/2023] Open
Abstract
Standard of care for triple-negative breast cancer (TNBC) involves the use of microtubule poisons such as paclitaxel, which are proposed to work by inducing lethal levels of aneuploidy in tumor cells. While these drugs are initially effective in treating cancer, dose-limiting peripheral neuropathies are common. Unfortunately, patients often relapse with drug-resistant tumors. Identifying agents against targets that limit aneuploidy may be a valuable approach for therapeutic development. One potential target is the microtubule depolymerizing kinesin, MCAK, which limits aneuploidy by regulating microtubule dynamics during mitosis. Using publicly available datasets, we found that MCAK is upregulated in triple-negative breast cancer and is associated with poorer prognoses. Knockdown of MCAK in tumor-derived cell lines caused a two- to five-fold reduction in the IC50 for paclitaxel, without affecting normal cells. Using FRET and image-based assays, we screened compounds from the ChemBridge 50 k library and discovered three putative MCAK inhibitors. These compounds reproduced the aneuploidy-inducing phenotype of MCAK loss, reduced clonogenic survival of TNBC cells regardless of taxane-resistance, and the most potent of the three, C4, sensitized TNBC cells to paclitaxel. Collectively, our work shows promise that MCAK may serve as both a biomarker of prognosis and as a therapeutic target.
Collapse
Affiliation(s)
- John C. Smith
- Medical Sciences, Indiana School of Medicine—Bloomington, Bloomington, IN 47405, USA; (J.C.S.); (S.C.E.-M.); (J.R.S.); (R.L.C.)
| | - Stefan Husted
- LabCorp Drug Development Indianapolis, Indianapolis, IN 46214, USA
| | - Jay Pilrose
- Catalent Pharma Solutions Bloomington, Bloomington, IN 47403, USA
| | - Stephanie C. Ems-McClung
- Medical Sciences, Indiana School of Medicine—Bloomington, Bloomington, IN 47405, USA; (J.C.S.); (S.C.E.-M.); (J.R.S.); (R.L.C.)
| | - Jane R. Stout
- Medical Sciences, Indiana School of Medicine—Bloomington, Bloomington, IN 47405, USA; (J.C.S.); (S.C.E.-M.); (J.R.S.); (R.L.C.)
| | - Richard L. Carpenter
- Medical Sciences, Indiana School of Medicine—Bloomington, Bloomington, IN 47405, USA; (J.C.S.); (S.C.E.-M.); (J.R.S.); (R.L.C.)
| | - Claire E. Walczak
- Medical Sciences, Indiana School of Medicine—Bloomington, Bloomington, IN 47405, USA; (J.C.S.); (S.C.E.-M.); (J.R.S.); (R.L.C.)
| |
Collapse
|
20
|
Smith JC, Husted S, Pilrose J, Ems-McClung SC, Stout JR, Carpenter RL, Walczak CE. MCAK Inhibitors Induce Aneuploidy in Triple Negative Breast Cancer Models. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.31.543118. [PMID: 37397990 PMCID: PMC10312595 DOI: 10.1101/2023.05.31.543118] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
Standard of care for triple negative breast cancer (TNBC) involves the use of microtubule poisons like paclitaxel, which are proposed to work by inducing lethal levels of aneuploidy in tumor cells. While these drugs are initially effective in treating cancer, dose-limiting peripheral neuropathies are common. Unfortunately, patients often relapse with drug resistant tumors. Identifying agents against targets that limit aneuploidy may be a valuable approach for therapeutic development. One potential target is the microtubule depolymerizing kinesin, MCAK, which limits aneuploidy by regulating microtubule dynamics during mitosis. Using publicly available datasets, we found that MCAK is upregulated in triple negative breast cancer and is associated with poorer prognoses. Knockdown of MCAK in tumor-derived cell lines caused a two- to five-fold reduction in the IC 50 for paclitaxel, without affecting normal cells. Using FRET and image-based assays, we screened compounds from the ChemBridge 50k library and discovered three putative MCAK inhibitors. These compounds reproduced the aneuploidy-inducing phenotype of MCAK loss, reduced clonogenic survival of TNBC cells regardless of taxane-resistance, and the most potent of the three, C4, sensitized TNBC cells to paclitaxel. Collectively, our work shows promise that MCAK may serve as both a biomarker of prognosis and as a therapeutic target. Simple Summary Triple negative breast cancer (TNBC) is the most lethal breast cancer subtype with few treatment options available. Standard of care for TNBC involves the use of taxanes, which are initially effective, but dose limiting toxicities are common, and patients often relapse with resistant tumors. Specific drugs that produce taxane-like effects may be able to improve patient quality of life and prognosis. In this study we identify three novel inhibitors of the Kinesin-13 MCAK. MCAK inhibition induces aneuploidy; similar to cells treated with taxanes. We demonstrate that MCAK is upregulated in TNBC and is associated with poorer prognoses. These MCAK inhibitors reduce the clonogenic survival of TNBC cells, and the most potent of the three inhibitors, C4, sensitizes TNBC cells to taxanes, similar to the effects of MCAK knockdown. This work will expand the field of precision medicine to include aneuploidy-inducing drugs that have the potential to improve patient outcomes.
Collapse
|
21
|
Schaer J, Andreu-Carbó M, Kruse K, Aumeier C. The effect of motor-induced shaft dynamics on microtubule stability and length. Biophys J 2023; 122:346-359. [PMID: 36502273 PMCID: PMC9892620 DOI: 10.1016/j.bpj.2022.12.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 10/17/2022] [Accepted: 12/05/2022] [Indexed: 12/14/2022] Open
Abstract
Control of microtubule abundance, stability, and length is crucial to regulate intracellular transport as well as cell polarity and division. How microtubule stability depends on tubulin addition or removal at the dynamic ends is well studied. However, microtubule rescue, the event when a microtubule switches from shrinking to growing, occurs at tubulin exchange sites along the shaft. Molecular motors have recently been shown to promote such exchanges. Using a stochastic theoretical description, we study how microtubule stability and length depend on motor-induced tubulin exchange and thus rescue. Our theoretical description matches our in vitro experiments on microtubule dynamics in the presence of kinesin-1 molecular motors. Although the overall dynamics of a population of microtubules can be captured by an effective rescue rate, by assigning rescue to exchange sites, we reveal that the dynamics of individual microtubules within the population differ dramatically. Furthermore, we study in detail a transition from bounded to unbounded microtubule growth. Our results provide novel insights into how molecular motors imprint information of microtubule stability on the microtubule network.
Collapse
Affiliation(s)
- Joël Schaer
- Department of Biochemistry, University of Geneva, Geneva, Switzerland; Department of Theoretical Physics, University of Geneva, Geneva, Switzerland
| | | | - Karsten Kruse
- Department of Biochemistry, University of Geneva, Geneva, Switzerland; Department of Theoretical Physics, University of Geneva, Geneva, Switzerland; National Center for Competence in Research Chemical Biology, University of Geneva, Geneva, Switzerland.
| | - Charlotte Aumeier
- Department of Biochemistry, University of Geneva, Geneva, Switzerland; National Center for Competence in Research Chemical Biology, University of Geneva, Geneva, Switzerland.
| |
Collapse
|
22
|
Xie P. A model for the catalytic activity of microtubule polymerases. Cytoskeleton (Hoboken) 2023; 80:7-20. [PMID: 36305831 DOI: 10.1002/cm.21734] [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: 06/13/2022] [Revised: 10/04/2022] [Accepted: 10/22/2022] [Indexed: 11/07/2022]
Abstract
A XMAP215/Stu2/Alp14 polymerase can catalyze processively the tubulin addition to the microtubule (MT) plus end. In this work, a model is proposed for the underlying molecular mechanism of the polymerase activity, where the polymerase can not only catalyze processively the tubulin addition to but also promote the tubulin removal from the MT plus end. Based on the model the dynamics of both the wild-type and mutant polymerases is studied theoretically, explaining consistently and well various available experimental data. To further test the model, predicted results are provided.
Collapse
Affiliation(s)
- Ping Xie
- Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Science, Beijing, China
| |
Collapse
|
23
|
Hoff KJ, Neumann AJ, Moore JK. The molecular biology of tubulinopathies: Understanding the impact of variants on tubulin structure and microtubule regulation. Front Cell Neurosci 2022; 16:1023267. [PMID: 36406756 PMCID: PMC9666403 DOI: 10.3389/fncel.2022.1023267] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Accepted: 09/30/2022] [Indexed: 11/24/2022] Open
Abstract
Heterozygous, missense mutations in both α- and β-tubulin genes have been linked to an array of neurodevelopment disorders, commonly referred to as "tubulinopathies." To date, tubulinopathy mutations have been identified in three β-tubulin isotypes and one α-tubulin isotype. These mutations occur throughout the different genetic domains and protein structures of these tubulin isotypes, and the field is working to address how this molecular-level diversity results in different cellular and tissue-level pathologies. Studies from many groups have focused on elucidating the consequences of individual mutations; however, the field lacks comprehensive models for the molecular etiology of different types of tubulinopathies, presenting a major gap in diagnosis and treatment. This review highlights recent advances in understanding tubulin structural dynamics, the roles microtubule-associated proteins (MAPs) play in microtubule regulation, and how these are inextricably linked. We emphasize the value of investigating interactions between tubulin structures, microtubules, and MAPs to understand and predict the impact of tubulinopathy mutations at the cell and tissue levels. Microtubule regulation is multifaceted and provides a complex set of controls for generating a functional cytoskeleton at the right place and right time during neurodevelopment. Understanding how tubulinopathy mutations disrupt distinct subsets of those controls, and how that ultimately disrupts neurodevelopment, will be important for establishing mechanistic themes among tubulinopathies that may lead to insights in other neurodevelopment disorders and normal neurodevelopment.
Collapse
Affiliation(s)
| | | | - Jeffrey K. Moore
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| |
Collapse
|
24
|
Taguchi S, Nakano J, Imasaki T, Kita T, Saijo-Hamano Y, Sakai N, Shigematsu H, Okuma H, Shimizu T, Nitta E, Kikkawa S, Mizobuchi S, Niwa S, Nitta R. Structural model of microtubule dynamics inhibition by kinesin-4 from the crystal structure of KLP-12 -tubulin complex. eLife 2022; 11:77877. [PMID: 36065637 PMCID: PMC9451533 DOI: 10.7554/elife.77877] [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: 02/14/2022] [Accepted: 08/01/2022] [Indexed: 12/02/2022] Open
Abstract
Kinesin superfamily proteins are microtubule-based molecular motors driven by the energy of ATP hydrolysis. Among them, the kinesin-4 family is a unique motor that inhibits microtubule dynamics. Although mutations of kinesin-4 cause several diseases, its molecular mechanism is unclear because of the difficulty of visualizing the high-resolution structure of kinesin-4 working at the microtubule plus-end. Here, we report that KLP-12, a C. elegans kinesin-4 ortholog of KIF21A and KIF21B, is essential for proper length control of C. elegans axons, and its motor domain represses microtubule polymerization in vitro. The crystal structure of the KLP-12 motor domain complexed with tubulin, which represents the high-resolution structural snapshot of the inhibition state of microtubule-end dynamics, revealed the bending effect of KLP-12 for tubulin. Comparison with the KIF5B-tubulin and KIF2C-tubulin complexes, which represent the elongation and shrinking forms of microtubule ends, respectively, showed the curvature of tubulin introduced by KLP-12 is in between them. Taken together, KLP-12 controls the proper length of axons by modulating the curvature of the microtubule ends to inhibit the microtubule dynamics. From meter-long structures that allow nerve cells to stretch across a body to miniscule ‘hairs’ required for lung cells to clear mucus, many life processes rely on cells sporting projections which have the right size for their role. Networks of hollow filaments known as microtubules shape these structures and ensure that they have the appropriate dimensions. Controlling the length of microtubules is therefore essential for organisms, yet how this process takes place is still not fully elucidated. Previous research has shown that microtubules continue to grow when their end is straight but stop when it is curved. A family of molecular motors known as kinesin-4 participate in this process, but the exact mechanisms at play remain unclear. To investigate, Tuguchi, Nakano, Imasaki et al. focused on the KLP-12 protein, a kinesin-4 equivalent which helps to controls the length of microtubules in the tiny worm Caenorhabditis elegans. They performed genetic manipulations and imaged the interactions between KLP-12 and the growing end of a microtubule using X-ray crystallography. This revealed that KLP-12 controls the length of neurons by inhibiting microtubule growth. It does so by modulating the curvature of the growing end of the filament to suppress its extension. A ‘snapshot’ of KLP-12 binding to a microtubule at the resolution of the atom revealed exactly how the protein helps to bend the end of the filament to prevent it from growing further. These results will help to understand how nerve cells are shaped. This may also provide insights into the molecular mechanisms for various neurodegenerative disorders caused by problems with the human equivalents of KLP-12, potentially leading to new therapies.
Collapse
Affiliation(s)
- Shinya Taguchi
- Division of Structural Medicine and Anatomy, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, Kobe, Japan.,Division of Anesthesiology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Juri Nakano
- Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Tsuyoshi Imasaki
- Division of Structural Medicine and Anatomy, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Tomoki Kita
- Department of Applied Physics, Graduate School of Engineering, Tohoku University, Sendai, Japan
| | - Yumiko Saijo-Hamano
- Division of Structural Medicine and Anatomy, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, Kobe, Japan
| | | | | | - Hiromichi Okuma
- Division of Structural Medicine and Anatomy, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Takahiro Shimizu
- Division of Structural Medicine and Anatomy, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Eriko Nitta
- Division of Structural Medicine and Anatomy, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Satoshi Kikkawa
- Division of Structural Medicine and Anatomy, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Satoshi Mizobuchi
- Division of Anesthesiology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Shinsuke Niwa
- Graduate School of Life Sciences, Tohoku University, Sendai, Japan.,Department of Applied Physics, Graduate School of Engineering, Tohoku University, Sendai, Japan.,Frontier Research Institute for Interdisciplinary Sciences (FRIS), Tohoku University, Sendai, Japan
| | - Ryo Nitta
- Division of Structural Medicine and Anatomy, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, Kobe, Japan
| |
Collapse
|
25
|
Belsham HR, Alghamdi HM, Dave N, Rathbone AJ, Wickstead B, Friel CT. A synthetic ancestral kinesin-13 depolymerizes microtubules faster than any natural depolymerizing kinesin. Open Biol 2022; 12:220133. [PMID: 36043268 PMCID: PMC9428548 DOI: 10.1098/rsob.220133] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The activity of a kinesin is largely determined by the approximately 350 residue motor domain, and this region alone is sufficient to classify a kinesin as a member of a particular family. The kinesin-13 family are a group of microtubule depolymerizing kinesins and are vital regulators of microtubule length. Kinesin-13s are critical to spindle assembly and chromosome segregation in both mitotic and meiotic cell division and play crucial roles in cilium length control and neuronal development. To better understand the evolution of microtubule depolymerization activity, we created a synthetic ancestral kinesin-13 motor domain. This phylogenetically inferred ancestral motor domain is the sequence predicted to have existed in the common ancestor of the kinesin-13 family. Here we show that the ancestral kinesin-13 motor depolymerizes stabilized microtubules faster than any previously tested depolymerase. This potent activity is more than an order of magnitude faster than the most highly studied kinesin-13, MCAK and allows the ancestral kinesin-13 to depolymerize doubly stabilized microtubules and cause internal breaks within microtubules. These data suggest that the ancestor of the kinesin-13 family was a 'super depolymerizer' and that members of the kinesin-13 family have evolved away from this extreme depolymerizing activity to provide more controlled microtubule depolymerization activity in extant cells.
Collapse
Affiliation(s)
- Hannah R Belsham
- School of Life Sciences, University of Nottingham, Medical School, QMC, Nottingham NG7 2UH, UK
| | - Hanan M Alghamdi
- School of Life Sciences, University of Nottingham, Medical School, QMC, Nottingham NG7 2UH, UK.,Biology Department, Faculty of Science, Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia
| | - Nikita Dave
- School of Life Sciences, University of Nottingham, Medical School, QMC, Nottingham NG7 2UH, UK
| | - Alexandra J Rathbone
- School of Life Sciences, University of Nottingham, Medical School, QMC, Nottingham NG7 2UH, UK
| | - Bill Wickstead
- School of Life Sciences, University of Nottingham, Medical School, QMC, Nottingham NG7 2UH, UK
| | - Claire T Friel
- School of Life Sciences, University of Nottingham, Medical School, QMC, Nottingham NG7 2UH, UK
| |
Collapse
|
26
|
Motor usage imprints microtubule stability along the shaft. Dev Cell 2021; 57:5-18.e8. [PMID: 34883065 DOI: 10.1016/j.devcel.2021.11.019] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 08/27/2021] [Accepted: 11/15/2021] [Indexed: 12/22/2022]
Abstract
Tubulin dimers assemble into dynamic microtubules, which are used by molecular motors as tracks for intracellular transport. Organization and dynamics of the microtubule network are commonly thought to be regulated at the polymer ends, where tubulin dimers can be added or removed. Here, we show that molecular motors running on microtubules cause exchange of dimers along the shaft in vitro and in cells. These sites of dimer exchange act as rescue sites where depolymerizing microtubules stop shrinking and start re-growing. Consequently, the average length of microtubules increases depending on how frequently they are used as motor tracks. An increase of motor activity densifies the cellular microtubule network and enhances cell polarity. Running motors leave marks in the shaft, serving as traces of microtubule usage to organize the polarity landscape of the cell.
Collapse
|
27
|
Schweiggert J, Habeck G, Hess S, Mikus F, Beloshistov R, Meese K, Hata S, Knobeloch K, Melchior F. SCF Fbxw5 targets kinesin-13 proteins to facilitate ciliogenesis. EMBO J 2021; 40:e107735. [PMID: 34368969 PMCID: PMC8441365 DOI: 10.15252/embj.2021107735] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 06/29/2021] [Accepted: 07/12/2021] [Indexed: 11/23/2022] Open
Abstract
Microtubule depolymerases of the kinesin-13 family play important roles in various cellular processes and are frequently overexpressed in different cancer types. Despite the importance of their correct abundance, remarkably little is known about how their levels are regulated in cells. Using comprehensive screening on protein microarrays, we identified 161 candidate substrates of the multi-subunit ubiquitin E3 ligase SCFFbxw5 , including the kinesin-13 member Kif2c/MCAK. In vitro reconstitution assays demonstrate that MCAK and its closely related orthologs Kif2a and Kif2b become efficiently polyubiquitylated by neddylated SCFFbxw5 and Cdc34, without requiring preceding modifications. In cells, SCFFbxw5 targets MCAK for proteasomal degradation predominantly during G2 . While this seems largely dispensable for mitotic progression, loss of Fbxw5 leads to increased MCAK levels at basal bodies and impairs ciliogenesis in the following G1 /G0 , which can be rescued by concomitant knockdown of MCAK, Kif2a or Kif2b. We thus propose a novel regulatory event of ciliogenesis that begins already within the G2 phase of the preceding cell cycle.
Collapse
Affiliation(s)
- Jörg Schweiggert
- Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH)University of HeidelbergDKFZ ‐ ZMBH AllianceHeidelbergGermany
| | - Gregor Habeck
- Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH)University of HeidelbergDKFZ ‐ ZMBH AllianceHeidelbergGermany
| | - Sandra Hess
- Institute of NeuropathologyFaculty of MedicineUniversity of FreiburgFreiburgGermany
- Faculty of BiologyUniversity of FreiburgFreiburgGermany
| | - Felix Mikus
- Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH)University of HeidelbergDKFZ ‐ ZMBH AllianceHeidelbergGermany
| | - Roman Beloshistov
- Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH)University of HeidelbergDKFZ ‐ ZMBH AllianceHeidelbergGermany
| | - Klaus Meese
- Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH)University of HeidelbergDKFZ ‐ ZMBH AllianceHeidelbergGermany
| | - Shoji Hata
- Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH)University of HeidelbergDKFZ ‐ ZMBH AllianceHeidelbergGermany
| | | | - Frauke Melchior
- Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH)University of HeidelbergDKFZ ‐ ZMBH AllianceHeidelbergGermany
| |
Collapse
|
28
|
Abstract
Female meiotic drive is the phenomenon where a selfish genetic element alters chromosome segregation during female meiosis to segregate to the egg and transmit to the next generation more frequently than Mendelian expectation. While several examples of female meiotic drive have been known for many decades, a molecular understanding of the underlying mechanisms has been elusive. Recent advances in this area in several model species prompts a comparative re-examination of these drive systems. In this review, we compare female meiotic drive of several animal and plant species, highlighting pertinent similarities.
Collapse
Affiliation(s)
- Frances E. Clark
- Cell and Developmental Biology Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Takashi Akera
- Cell and Developmental Biology Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| |
Collapse
|
29
|
Xie P. Modeling processive motion of kinesin-13 MCAK and kinesin-14 Cik1-Kar3 molecular motors. Protein Sci 2021; 30:2092-2105. [PMID: 34382258 DOI: 10.1002/pro.4165] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 08/02/2021] [Accepted: 08/04/2021] [Indexed: 11/09/2022]
Abstract
Kinesin-13 MCAK, which is composed of two identical motor domains, can undergo unbiased one-dimensional diffusion on microtubules. Kinesin-14 Cik1-Kar3, which is composed of a Kar3 motor domain and a Cik1 motor homology domain with no ATPase activity, can move processively toward the minus end of microtubules. Here, we present a model for the diffusion of MCAK homodimer and a model for the processive motion of Cik1-Kar3 heterodimer. Although the two dimeric motors show different domain composition, in the models it is proposed that the two motors use the similar physical mechanism to move processively. With the models, the dynamics of the two dimers is studied analytically. The theoretical results for MCAK reproduce quantitatively the available experimental data about diffusion constant and lifetime of the motor bound to microtubule in different nucleotide states. The theoretical results for Cik1-Kar3 reproduce quantitatively the available experimental data about load dependence of velocity and explain consistently the available experimental data about effects of the exchange and mutation of the motor homology domain on the velocity of the heterodimer. Moreover, predicted results for other aspects of the dynamics of the two dimers are provided.
Collapse
Affiliation(s)
- Ping Xie
- Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China
| |
Collapse
|
30
|
Farmer V, Arpağ G, Hall SL, Zanic M. XMAP215 promotes microtubule catastrophe by disrupting the growing microtubule end. J Cell Biol 2021; 220:212518. [PMID: 34324632 PMCID: PMC8327381 DOI: 10.1083/jcb.202012144] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 05/11/2021] [Accepted: 07/08/2021] [Indexed: 01/13/2023] Open
Abstract
The GTP-tubulin cap is widely accepted to protect microtubules against catastrophe. The GTP-cap size is thought to increase with the microtubule growth rate, presumably endowing fast-growing microtubules with enhanced stability. It is unknown what GTP-cap properties permit frequent microtubule catastrophe despite fast growth. Here, we investigate microtubules growing in the presence and absence of the polymerase XMAP215. Using EB1 as a GTP-cap marker, we find that GTP-cap size increases regardless of whether growth acceleration is achieved by increasing tubulin concentration or by XMAP215. Despite increased mean GTP-cap size, microtubules grown with XMAP215 display increased catastrophe frequency, in contrast to microtubules grown with more tubulin, for which catastrophe is abolished. However, microtubules polymerized with XMAP215 have large fluctuations in growth rate; display tapered and curled ends; and undergo catastrophe at faster growth rates and with higher EB1 end-localization. Our results suggest that structural perturbations induced by XMAP215 override the protective effects of the GTP-cap, ultimately driving microtubule catastrophe.
Collapse
Affiliation(s)
- Veronica Farmer
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN
| | - Göker Arpağ
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN
| | - Sarah L Hall
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN
| | - Marija Zanic
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN.,Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN.,Department of Biochemistry, Vanderbilt University, Nashville, TN
| |
Collapse
|
31
|
Triclin S, Inoue D, Gaillard J, Htet ZM, DeSantis ME, Portran D, Derivery E, Aumeier C, Schaedel L, John K, Leterrier C, Reck-Peterson SL, Blanchoin L, Théry M. Self-repair protects microtubules from destruction by molecular motors. NATURE MATERIALS 2021; 20:883-891. [PMID: 33479528 PMCID: PMC7611741 DOI: 10.1038/s41563-020-00905-0] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 12/09/2020] [Indexed: 05/30/2023]
Abstract
Microtubule instability stems from the low energy of tubulin dimer interactions, which sets the growing polymer close to its disassembly conditions. Molecular motors use ATP hydrolysis to produce mechanical work and move on microtubules. This raises the possibility that the mechanical work produced by walking motors can break dimer interactions and trigger microtubule disassembly. We tested this hypothesis by studying the interplay between microtubules and moving molecular motors in vitro. Our results show that molecular motors can remove tubulin dimers from the lattice and rapidly destroy microtubules. We also found that dimer removal by motors was compensated for by the insertion of free tubulin dimers into the microtubule lattice. This self-repair mechanism allows microtubules to survive the damage induced by molecular motors as they move along their tracks. Our study reveals the existence of coupling between the motion of molecular motors and the renewal of the microtubule lattice.
Collapse
Affiliation(s)
- Sarah Triclin
- Interdisciplinary Research Institute of Grenoble, Laboratoire de Physiologie Cellulaire & Végétale, CytoMorpho Lab, University of Grenoble-Alpes, CEA, CNRS, INRA, Grenoble, France
| | - Daisuke Inoue
- Interdisciplinary Research Institute of Grenoble, Laboratoire de Physiologie Cellulaire & Végétale, CytoMorpho Lab, University of Grenoble-Alpes, CEA, CNRS, INRA, Grenoble, France
- Department of Human Science, Faculty of Design, Kyushu University, Fukuoka, Japan
| | - Jérémie Gaillard
- Interdisciplinary Research Institute of Grenoble, Laboratoire de Physiologie Cellulaire & Végétale, CytoMorpho Lab, University of Grenoble-Alpes, CEA, CNRS, INRA, Grenoble, France
| | - Zaw Min Htet
- Deptartment of Cellular and Molecular Medicine, and Cell and Developmental Biology Section, Division of Biological Sciences, University of California San Diego, La Jolla, CA, USA
| | - Morgan E DeSantis
- Deptartment of Cellular and Molecular Medicine, and Cell and Developmental Biology Section, Division of Biological Sciences, University of California San Diego, La Jolla, CA, USA
| | - Didier Portran
- CRBM, University of Montpellier, CNRS, Montpellier, France
| | - Emmanuel Derivery
- MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge, UK
| | - Charlotte Aumeier
- Department of Biochemistry, University of Geneva, Genève, Switzerland
| | - Laura Schaedel
- Interdisciplinary Research Institute of Grenoble, Laboratoire de Physiologie Cellulaire & Végétale, CytoMorpho Lab, University of Grenoble-Alpes, CEA, CNRS, INRA, Grenoble, France
| | - Karin John
- Laboratoire Interdisciplinaire de Physique, University of Grenoble-Alpes, CNRS, Grenoble, France
| | | | - Samara L Reck-Peterson
- Deptartment of Cellular and Molecular Medicine, and Cell and Developmental Biology Section, Division of Biological Sciences, University of California San Diego, La Jolla, CA, USA
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Laurent Blanchoin
- Interdisciplinary Research Institute of Grenoble, Laboratoire de Physiologie Cellulaire & Végétale, CytoMorpho Lab, University of Grenoble-Alpes, CEA, CNRS, INRA, Grenoble, France.
- Institut de Recherche Saint Louis, U976 Human Immunology Pathophysiology Immunotherapy (HIPI), CytoMorpho Lab, University of Paris, INSERM, CEA, Paris, France.
| | - Manuel Théry
- Interdisciplinary Research Institute of Grenoble, Laboratoire de Physiologie Cellulaire & Végétale, CytoMorpho Lab, University of Grenoble-Alpes, CEA, CNRS, INRA, Grenoble, France.
- Institut de Recherche Saint Louis, U976 Human Immunology Pathophysiology Immunotherapy (HIPI), CytoMorpho Lab, University of Paris, INSERM, CEA, Paris, France.
| |
Collapse
|
32
|
Risteski P, Jagrić M, Pavin N, Tolić IM. Biomechanics of chromosome alignment at the spindle midplane. Curr Biol 2021; 31:R574-R585. [PMID: 34033791 DOI: 10.1016/j.cub.2021.03.082] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
During metaphase, chromosomes are aligned in a lineup at the equatorial plane of the spindle to ensure synchronous poleward movement of chromatids in anaphase and proper nuclear reformation at the end of mitosis. Chromosome alignment relies on microtubules, several types of motor protein and numerous other microtubule-associated and regulatory proteins. Because of the multitude of players involved, the mechanisms of chromosome alignment are still under debate. Here, we discuss the current models of alignment based on poleward pulling forces exerted onto sister kinetochores by kinetochore microtubules, which show length-dependent dynamics and undergo poleward flux, and polar ejection forces that push the chromosome arms away from the pole. We link these models with the recent ideas based on mechanical coupling between bridging and kinetochore microtubules, where sliding of bridging microtubules promotes overlap length-dependent sliding of kinetochore fibers and thus the alignment of sister kinetochores at the spindle equator. Finally, we discuss theoretical models of forces acting on chromosomes during metaphase.
Collapse
Affiliation(s)
- Patrik Risteski
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia
| | - Mihaela Jagrić
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia
| | - Nenad Pavin
- Department of Physics, Faculty of Science, University of Zagreb, Bijenička cesta 32, 10000 Zagreb, Croatia
| | - Iva M Tolić
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia.
| |
Collapse
|
33
|
How Kinesin-1 Utilize the Energy of Nucleotide: The Conformational Changes and Mechanochemical Coupling in the Unidirectional Motion of Kinesin-1. Int J Mol Sci 2020; 21:ijms21186977. [PMID: 32972035 PMCID: PMC7555842 DOI: 10.3390/ijms21186977] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 09/12/2020] [Accepted: 09/21/2020] [Indexed: 12/23/2022] Open
Abstract
Kinesin-1 is a typical motile molecular motor and the founding member of the kinesin family. The most significant feature in the unidirectional motion of kinesin-1 is its processivity. To realize the fast and processive movement on the microtubule lattice, kinesin-1 efficiently transforms the chemical energy of nucleotide binding and hydrolysis to the energy of mechanical movement. The chemical and mechanical cycle of kinesin-1 are coupled to avoid futile nucleotide hydrolysis. In this paper, the research on the mechanical pathway of energy transition and the regulating mechanism of the mechanochemical cycle of kinesin-1 is reviewed.
Collapse
|
34
|
Forkosh E, Kenig A, Ilan Y. Introducing variability in targeting the microtubules: Review of current mechanisms and future directions in colchicine therapy. Pharmacol Res Perspect 2020; 8:e00616. [PMID: 32608157 PMCID: PMC7327382 DOI: 10.1002/prp2.616] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Accepted: 05/25/2020] [Indexed: 12/14/2022] Open
Abstract
Microtubules (MTs) are highly dynamic polymers that constitute the cellular cytoskeleton and play a role in multiple cellular functions. Variability characterizes biological systems and is considered a part of the normal function of cells and organs. Variability contributes to cell plasticity and is a mechanism for overcoming errors in cellular level assembly and function, and potentially the whole organ level. Dynamic instability is a feature of biological variability that characterizes the function of MTs. The dynamic behavior of MTs constitutes the basis for multiple biological processes that contribute to cellular plasticity and the timing of cell signaling. Colchicine is a MT-modifying drug that exerts anti-inflammatory and anti-cancer effects. This review discusses some of the functions of colchicine and presents a platform for introducing variability while targeting MTs in intestinal cells, the microbiome, the gut, and the systemic immune system. This platform can be used for implementing novel therapies, improving response to chronic MT-based therapies, overcoming drug resistance, exerting gut-based systemic immune responses, and generating patient-tailored dynamic therapeutic regimens.
Collapse
Affiliation(s)
- Esther Forkosh
- Department of MedicineHebrew University‐Hadassah Medical CentreJerusalemIsrael
| | - Ariel Kenig
- Department of MedicineHebrew University‐Hadassah Medical CentreJerusalemIsrael
| | - Yaron Ilan
- Department of MedicineHebrew University‐Hadassah Medical CentreJerusalemIsrael
| |
Collapse
|
35
|
Hunter B, Allingham JS. These motors were made for walking. Protein Sci 2020; 29:1707-1723. [PMID: 32472639 DOI: 10.1002/pro.3895] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 05/19/2020] [Accepted: 05/22/2020] [Indexed: 12/21/2022]
Abstract
Kinesins are a diverse group of adenosine triphosphate (ATP)-dependent motor proteins that transport cargos along microtubules (MTs) and change the organization of MT networks. Shared among all kinesins is a ~40 kDa motor domain that has evolved an impressive assortment of motility and MT remodeling mechanisms as a result of subtle tweaks and edits within its sequence. Several elegant studies of different kinesin isoforms have exposed the purpose of structural changes in the motor domain as it engages and leaves the MT. However, few studies have compared the sequences and MT contacts of these kinesins systematically. Along with clever strategies to trap kinesin-tubulin complexes for X-ray crystallography, new advancements in cryo-electron microscopy have produced a burst of high-resolution structures that show kinesin-MT interfaces more precisely than ever. This review considers the MT interactions of kinesin subfamilies that exhibit significant differences in speed, processivity, and MT remodeling activity. We show how their sequence variations relate to their tubulin footprint and, in turn, how this explains the molecular activities of previously characterized mutants. As more high-resolution structures become available, this type of assessment will quicken the pace toward establishing each kinesin's design-function relationship.
Collapse
Affiliation(s)
- Byron Hunter
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada
| | - John S Allingham
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada
| |
Collapse
|
36
|
Thawani A, Rale MJ, Coudray N, Bhabha G, Stone HA, Shaevitz JW, Petry S. The transition state and regulation of γ-TuRC-mediated microtubule nucleation revealed by single molecule microscopy. eLife 2020; 9:e54253. [PMID: 32538784 PMCID: PMC7338055 DOI: 10.7554/elife.54253] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2019] [Accepted: 06/15/2020] [Indexed: 12/31/2022] Open
Abstract
Determining how microtubules (MTs) are nucleated is essential for understanding how the cytoskeleton assembles. While the MT nucleator, γ-tubulin ring complex (γ-TuRC) has been identified, precisely how γ-TuRC nucleates a MT remains poorly understood. Here, we developed a single molecule assay to directly visualize nucleation of a MT from purified Xenopus laevis γ-TuRC. We reveal a high γ-/αβ-tubulin affinity, which facilitates assembly of a MT from γ-TuRC. Whereas spontaneous nucleation requires assembly of 8 αβ-tubulins, nucleation from γ-TuRC occurs efficiently with a cooperativity of 4 αβ-tubulin dimers. This is distinct from pre-assembled MT seeds, where a single dimer is sufficient to initiate growth. A computational model predicts our kinetic measurements and reveals the rate-limiting transition where laterally associated αβ-tubulins drive γ-TuRC into a closed conformation. NME7, TPX2, and the putative activation domain of CDK5RAP2 h γ-TuRC-mediated nucleation, while XMAP215 drastically increases the nucleation efficiency by strengthening the longitudinal γ-/αβ-tubulin interaction.
Collapse
Affiliation(s)
- Akanksha Thawani
- Department of Chemical and Biological Engineering, Princeton UniversityPrincetonUnited States
| | - Michael J Rale
- Department of Molecular Biology, Princeton UniversityPrincetonUnited States
| | - Nicolas Coudray
- Department of Cell Biology, New York University School of MedicineNew YorkUnited States
| | - Gira Bhabha
- Department of Cell Biology, New York University School of MedicineNew YorkUnited States
| | - Howard A Stone
- Department of Mechanical and Aerospace Engineering, Princeton UniversityPrincetonUnited States
| | - Joshua W Shaevitz
- Lewis-Sigler Institute for Integrative GenomicsPrincetonUnited States
- Department of Physics, Princeton UniversityPrincetonUnited States
| | - Sabine Petry
- Department of Molecular Biology, Princeton UniversityPrincetonUnited States
| |
Collapse
|
37
|
Organ of Corti size is governed by Yap/Tead-mediated progenitor self-renewal. Proc Natl Acad Sci U S A 2020; 117:13552-13561. [PMID: 32482884 DOI: 10.1073/pnas.2000175117] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Precise control of organ growth and patterning is executed through a balanced regulation of progenitor self-renewal and differentiation. In the auditory sensory epithelium-the organ of Corti-progenitor cells exit the cell cycle in a coordinated wave between E12.5 and E14.5 before the initiation of sensory receptor cell differentiation, making it a unique system for studying the molecular mechanisms controlling the switch between proliferation and differentiation. Here we identify the Yap/Tead complex as a key regulator of the self-renewal gene network in organ of Corti progenitor cells. We show that Tead transcription factors bind directly to the putative regulatory elements of many stemness- and cell cycle-related genes. We also show that the Tead coactivator protein, Yap, is degraded specifically in the Sox2-positive domain of the cochlear duct, resulting in down-regulation of Tead gene targets. Further, conditional loss of the Yap gene in the inner ear results in the formation of significantly smaller auditory and vestibular sensory epithelia, while conditional overexpression of a constitutively active version of Yap, Yap5SA, is sufficient to prevent cell cycle exit and to prolong sensory tissue growth. We also show that viral gene delivery of Yap5SA in the postnatal inner ear sensory epithelia in vivo drives cell cycle reentry after hair cell loss. Taken together, these data highlight the key role of the Yap/Tead transcription factor complex in maintaining inner ear progenitors during development, and suggest new strategies to induce sensory cell regeneration.
Collapse
|
38
|
Tempes A, Weslawski J, Brzozowska A, Jaworski J. Role of dynein-dynactin complex, kinesins, motor adaptors, and their phosphorylation in dendritogenesis. J Neurochem 2020; 155:10-28. [PMID: 32196676 DOI: 10.1111/jnc.15010] [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: 01/28/2020] [Revised: 02/24/2020] [Accepted: 03/13/2020] [Indexed: 12/21/2022]
Abstract
One of the characteristic features of different classes of neurons that is vital for their proper functioning within neuronal networks is the shape of their dendritic arbors. To properly develop dendritic trees, neurons need to accurately control the intracellular transport of various cellular cargo (e.g., mRNA, proteins, and organelles). Microtubules and motor proteins (e.g., dynein and kinesins) that move along microtubule tracks play an essential role in cargo sorting and transport to the most distal ends of neurons. Equally important are motor adaptors, which may affect motor activity and specify cargo that is transported by the motor. Such transport undergoes very dynamic fine-tuning in response to changes in the extracellular environment and synaptic transmission. Such regulation is achieved by the phosphorylation of motors, motor adaptors, and cargo, among other mechanisms. This review focuses on the contribution of the dynein-dynactin complex, kinesins, their adaptors, and the phosphorylation of these proteins in the formation of dendritic trees by maturing neurons. We primarily review the effects of the motor activity of these proteins in dendrites on dendritogenesis. We also discuss less anticipated mechanisms that contribute to dendrite growth, such as dynein-driven axonal transport and non-motor functions of kinesins.
Collapse
Affiliation(s)
- Aleksandra Tempes
- Laboratory of Molecular and Cellular Neurobiology, International Institute of Molecular and Cell Biology, Warsaw, Poland
| | - Jan Weslawski
- Laboratory of Molecular and Cellular Neurobiology, International Institute of Molecular and Cell Biology, Warsaw, Poland
| | - Agnieszka Brzozowska
- Laboratory of Molecular and Cellular Neurobiology, International Institute of Molecular and Cell Biology, Warsaw, Poland
| | - Jacek Jaworski
- Laboratory of Molecular and Cellular Neurobiology, International Institute of Molecular and Cell Biology, Warsaw, Poland
| |
Collapse
|
39
|
Tang Q, Rui M, Bu S, Wang Y, Chew LY, Yu F. A microtubule polymerase is required for microtubule orientation and dendrite pruning in Drosophila. EMBO J 2020; 39:e103549. [PMID: 32267553 DOI: 10.15252/embj.2019103549] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 02/27/2020] [Accepted: 02/28/2020] [Indexed: 01/12/2023] Open
Abstract
Drosophila class IV ddaC neurons selectively prune all larval dendrites to refine the nervous system during metamorphosis. During dendrite pruning, severing of proximal dendrites is preceded by local microtubule (MT) disassembly. Here, we identify an unexpected role of Mini spindles (Msps), a conserved MT polymerase, in governing dendrite pruning. Msps associates with another MT-associated protein TACC, and both stabilize each other in ddaC neurons. Moreover, Msps and TACC are required to orient minus-end-out MTs in dendrites. We further show that the functions of msps in dendritic MT orientation and dendrite pruning are antagonized by the kinesin-13 MT depolymerase Klp10A. Excessive MT depolymerization, which is induced by pharmacological treatment and katanin overexpression, also perturbs dendritic MT orientation and dendrite pruning, phenocopying msps mutants. Thus, we demonstrate that the MT polymerase Msps is required to form dendritic minus-end-out MTs and thereby promotes dendrite pruning in Drosophila sensory neurons.
Collapse
Affiliation(s)
- Quan Tang
- Temasek Life Sciences Laboratory, Singapore City, Singapore.,Department of Biological Sciences, National University of Singapore, Singapore City, Singapore
| | - Menglong Rui
- Temasek Life Sciences Laboratory, Singapore City, Singapore
| | - Shufeng Bu
- Temasek Life Sciences Laboratory, Singapore City, Singapore.,Department of Biological Sciences, National University of Singapore, Singapore City, Singapore
| | - Yan Wang
- Temasek Life Sciences Laboratory, Singapore City, Singapore
| | - Liang Yuh Chew
- Temasek Life Sciences Laboratory, Singapore City, Singapore.,Department of Biological Sciences, National University of Singapore, Singapore City, Singapore
| | - Fengwei Yu
- Temasek Life Sciences Laboratory, Singapore City, Singapore.,Department of Biological Sciences, National University of Singapore, Singapore City, Singapore.,NUS Graduate School for Integrative Sciences and Engineering, Centre for Life Sciences, Singapore City, Singapore.,Neuroscience and Behavioral Disorder Program, Duke-NUS Graduate Medical School Singapore, Singapore City, Singapore
| |
Collapse
|
40
|
Bugiel M, Chugh M, Jachowski TJ, Schäffer E, Jannasch A. The Kinesin-8 Kip3 Depolymerizes Microtubules with a Collective Force-Dependent Mechanism. Biophys J 2020; 118:1958-1967. [PMID: 32229316 DOI: 10.1016/j.bpj.2020.02.030] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 01/29/2020] [Accepted: 02/25/2020] [Indexed: 12/28/2022] Open
Abstract
Microtubules are highly dynamic filaments with dramatic structural rearrangements and length changes during the cell cycle. An accurate control of the microtubule length is essential for many cellular processes, in particular during cell division. Motor proteins from the kinesin-8 family depolymerize microtubules by interacting with their ends in a collective and length-dependent manner. However, it is still unclear how kinesin-8 depolymerizes microtubules. Here, we tracked the microtubule end-binding activity of yeast kinesin-8, Kip3, under varying loads and nucleotide conditions using high-precision optical tweezers. We found that single Kip3 motors spent up to 200 s at the microtubule end and were not stationary there but took several 8-nm forward and backward steps that were suppressed by loads. Interestingly, increased loads, similar to increased motor concentrations, also exponentially decreased the motors' residence time at the microtubule end. On the microtubule lattice, loads also exponentially decreased the run length and time. However, for the same load, lattice run times were significantly longer compared to end residence times, suggesting the presence of a distinct force-dependent detachment mechanism at the microtubule end. The force dependence of the end residence time enabled us to estimate what force must act on a single motor to achieve the microtubule depolymerization speed of a motor ensemble. This force is higher than the stall force of a single Kip3 motor, supporting a collective force-dependent depolymerization mechanism that unifies the so-called "bump-off" and "switching" models. Understanding the mechanics of kinesin-8's microtubule end activity will provide important insights into cell division with implications for cancer research.
Collapse
Affiliation(s)
- Michael Bugiel
- Cellular Nanoscience, Center for Plant Molecular Biology (ZMBP), University of Tübingen, Tübingen, Germany
| | - Mayank Chugh
- Cellular Nanoscience, Center for Plant Molecular Biology (ZMBP), University of Tübingen, Tübingen, Germany
| | - Tobias Jörg Jachowski
- Cellular Nanoscience, Center for Plant Molecular Biology (ZMBP), University of Tübingen, Tübingen, Germany
| | - Erik Schäffer
- Cellular Nanoscience, Center for Plant Molecular Biology (ZMBP), University of Tübingen, Tübingen, Germany.
| | - Anita Jannasch
- Cellular Nanoscience, Center for Plant Molecular Biology (ZMBP), University of Tübingen, Tübingen, Germany.
| |
Collapse
|
41
|
Zhu S, Paydar M, Wang F, Li Y, Wang L, Barrette B, Bessho T, Kwok BH, Peng A. Kinesin Kif2C in regulation of DNA double strand break dynamics and repair. eLife 2020; 9:53402. [PMID: 31951198 PMCID: PMC7012618 DOI: 10.7554/elife.53402] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Accepted: 01/16/2020] [Indexed: 12/12/2022] Open
Abstract
DNA double strand breaks (DSBs) have detrimental effects on cell survival and genomic stability, and are related to cancer and other human diseases. In this study, we identified microtubule-depolymerizing kinesin Kif2C as a protein associated with DSB-mimicking DNA templates and known DSB repair proteins in Xenopus egg extracts and mammalian cells. The recruitment of Kif2C to DNA damage sites was dependent on both PARP and ATM activities. Kif2C knockdown or knockout led to accumulation of endogenous DNA damage, DNA damage hypersensitivity, and reduced DSB repair via both NHEJ and HR. Interestingly, Kif2C depletion, or inhibition of its microtubule depolymerase activity, reduced the mobility of DSBs, impaired the formation of DNA damage foci, and decreased the occurrence of foci fusion and resolution. Taken together, our study established Kif2C as a new player of the DNA damage response, and presented a new mechanism that governs DSB dynamics and repair.
Collapse
Affiliation(s)
- Songli Zhu
- Department of Oral Biology, College of Dentistry, University of Nebraska Medical Center, Omaha, United States
| | - Mohammadjavad Paydar
- Institute for Research in Immunology and Cancer (IRIC), Département de médecine, Université de Montréal, Montréal, Canada
| | - Feifei Wang
- Department of Oral Biology, College of Dentistry, University of Nebraska Medical Center, Omaha, United States.,Institute of Physical Science and Information Technology, Anhui University, Hefei, China
| | - Yanqiu Li
- Department of Oral Biology, College of Dentistry, University of Nebraska Medical Center, Omaha, United States
| | - Ling Wang
- Department of Oral Biology, College of Dentistry, University of Nebraska Medical Center, Omaha, United States
| | - Benoit Barrette
- Institute for Research in Immunology and Cancer (IRIC), Département de médecine, Université de Montréal, Montréal, Canada
| | - Tadayoshi Bessho
- Eppley Institute for Research in Cancer and Allied Diseases, Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, United States
| | - Benjamin H Kwok
- Institute for Research in Immunology and Cancer (IRIC), Département de médecine, Université de Montréal, Montréal, Canada
| | - Aimin Peng
- Department of Oral Biology, College of Dentistry, University of Nebraska Medical Center, Omaha, United States
| |
Collapse
|
42
|
Kim CD, Kim ED, Liu L, Buckley RS, Parameswaran S, Kim S, Wojcik EJ. Small molecule allosteric uncoupling of microtubule depolymerase activity from motility in human Kinesin-5 during mitotic spindle assembly. Sci Rep 2019; 9:19900. [PMID: 31882607 PMCID: PMC6934681 DOI: 10.1038/s41598-019-56173-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Accepted: 12/06/2019] [Indexed: 01/22/2023] Open
Abstract
Human Kinesin-5 (Eg5) has a large number of known allosteric inhibitors that disrupt its mitotic function. Small-molecule inhibitors of Eg5 are candidate anti-cancer agents and important probes for understanding the cellular function. Here we show that Eg5 is capable of more than one type of microtubule interaction, and these activities can be controlled by allosteric agents. While both monastrol and S-trityl-L-cysteine inhibit Eg5 motility, our data reveal an unexpected ability of these loop5 targeting inhibitors to differentially control a novel Eg5 microtubule depolymerizing activity. Remarkably, small molecule loop5 effectors are able to independently modulate discrete functional interactions between the motor and microtubule track. We establish that motility can be uncoupled from the microtubule depolymerase activity and argue that loop5-targeting inhibitors of Kinesin-5 should not all be considered functionally synonymous. Also, the depolymerizing activity of the motor does not contribute to the genesis of monopolar spindles during allosteric inhibition of motility, but instead reveals a new function. We propose that, in addition to its canonical role in participating in the construction of the three-dimensional mitotic spindle structure, Eg5 also plays a distinct role in regulating the dynamics of individual microtubules, and thereby impacts the density of the mitotic spindle.
Collapse
Affiliation(s)
- Catherine D Kim
- Department of Biochemistry and Molecular Biology, LSU School of Medicine & Health Sciences Center, 1901 Perdido Street, New Orleans, LA, 70112, USA
| | - Elizabeth D Kim
- Department of Biochemistry and Molecular Biology, LSU School of Medicine & Health Sciences Center, 1901 Perdido Street, New Orleans, LA, 70112, USA
| | - Liqiong Liu
- Department of Biochemistry and Molecular Biology, LSU School of Medicine & Health Sciences Center, 1901 Perdido Street, New Orleans, LA, 70112, USA
| | - Rebecca S Buckley
- Department of Biochemistry and Molecular Biology, LSU School of Medicine & Health Sciences Center, 1901 Perdido Street, New Orleans, LA, 70112, USA
| | - Sreeja Parameswaran
- Department of Biochemistry and Molecular Biology, LSU School of Medicine & Health Sciences Center, 1901 Perdido Street, New Orleans, LA, 70112, USA
| | - Sunyoung Kim
- Department of Biochemistry and Molecular Biology, LSU School of Medicine & Health Sciences Center, 1901 Perdido Street, New Orleans, LA, 70112, USA
| | - Edward J Wojcik
- Department of Biochemistry and Molecular Biology, LSU School of Medicine & Health Sciences Center, 1901 Perdido Street, New Orleans, LA, 70112, USA.
| |
Collapse
|
43
|
McInally SG, Kondev J, Dawson SC. Length-dependent disassembly maintains four different flagellar lengths in Giardia. eLife 2019; 8:e48694. [PMID: 31855176 PMCID: PMC6992383 DOI: 10.7554/elife.48694] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 12/18/2019] [Indexed: 01/03/2023] Open
Abstract
With eight flagella of four different lengths, the parasitic protist Giardia is an ideal model to evaluate flagellar assembly and length regulation. To determine how four different flagellar lengths are maintained, we used live-cell quantitative imaging and mathematical modeling of conserved components of intraflagellar transport (IFT)-mediated assembly and kinesin-13-mediated disassembly in different flagellar pairs. Each axoneme has a long cytoplasmic region extending from the basal body, and transitions to a canonical membrane-bound flagellum at the 'flagellar pore'. We determined that each flagellar pore is the site of IFT accumulation and injection, defining a diffusion barrier functionally analogous to the transition zone. IFT-mediated assembly is length-independent, as train size, speed, and injection frequencies are similar for all flagella. We demonstrate that kinesin-13 localization to the flagellar tips is inversely correlated to flagellar length. Therefore, we propose a model where a length-dependent disassembly mechanism controls multiple flagellar lengths within the same cell.
Collapse
Affiliation(s)
- Shane G McInally
- Department of Microbiology and Molecular GeneticsUniversity of California, DavisDavisUnited States
| | - Jane Kondev
- Department of PhysicsBrandeis UniversityWalthamUnited States
| | - Scott C Dawson
- Department of Microbiology and Molecular GeneticsUniversity of California, DavisDavisUnited States
| |
Collapse
|
44
|
Liu D, Miao Z, Wu C, He F, Ren P, Bai S, Jiang X, Gao Y. Isothermal kinase-triggered supramolecular assemblies as drug sensitizers. Chem Sci 2019; 11:1132-1139. [PMID: 34084370 PMCID: PMC8145944 DOI: 10.1039/c9sc04317a] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Protein kinases, the main regulators of a vast map of cellular processes, are the most attractive targets in drug discovery. Despite a few successful examples of protein kinase inhibitors, the drug discovery strategy of downregulating protein kinase activity has been quite limited and often fails even in animal models. Here, we utilize protein kinase A (PKA) activity to design PKA-triggered supramolecular assemblies with anticancer activities. Grafting a suitable peptide to PNIPAM raises the critical temperature of the LCST polymer above body temperature. Interestingly, the corresponding phosphorylated polymer has a critical temperature below body temperature, making this peptide-appended PNIPAM a suitable polymer for the PKA-triggered supramolecular assembly process. PKA-triggered assembly occurs selectively in PKA-upregulated MCF-7 cells, which disturbs the cytoskeleton and sensitizes cancer cells against doxorubicin. The chemosensitization is also observed in vivo to identify effective tumor inhibitors with satisfactory biocompatibility. Overall, this phosphorylation-induced (in principle, PKA-catalyzed) supramolecular assembly opens up a promising chemotherapy strategy for combating kinase-upregulated cancer. A nonapeptide grafted LCST polymer undergoes enzymatic phosphorylation to assemble, which selectively disrupts PKA overexpressing cancer cells via kinetics targeting.![]()
Collapse
Affiliation(s)
- Dongdong Liu
- CAS Center for Excellence in Nanoscience, CAS Key Laboratory of Biomedical Effects of Nanomaterials and Nanosafety, National Center for Nanoscience and Technology Beijing 100190 P. R. China .,Sino-Danish College, University of Chinese Academy of Sciences Beijing 100049 P. R. China
| | - Zhe Miao
- CAS Center for Excellence in Nanoscience, CAS Key Laboratory of Biomedical Effects of Nanomaterials and Nanosafety, National Center for Nanoscience and Technology Beijing 100190 P. R. China
| | - Chengling Wu
- CAS Center for Excellence in Nanoscience, CAS Key Laboratory of Biomedical Effects of Nanomaterials and Nanosafety, National Center for Nanoscience and Technology Beijing 100190 P. R. China
| | - Fangfei He
- CAS Center for Excellence in Nanoscience, CAS Key Laboratory of Biomedical Effects of Nanomaterials and Nanosafety, National Center for Nanoscience and Technology Beijing 100190 P. R. China
| | - Peng Ren
- Institute of Process Engineering, Chinese Academy of Sciences Beijing 100190 P. R. China
| | - Shuo Bai
- Institute of Process Engineering, Chinese Academy of Sciences Beijing 100190 P. R. China
| | - Xingyu Jiang
- CAS Center for Excellence in Nanoscience, CAS Key Laboratory of Biomedical Effects of Nanomaterials and Nanosafety, National Center for Nanoscience and Technology Beijing 100190 P. R. China .,Sino-Danish College, University of Chinese Academy of Sciences Beijing 100049 P. R. China.,Department of Biomedical Engineering, Southern University of Science & Technology Shenzhen 518055 Guangdong P. R. China
| | - Yuan Gao
- CAS Center for Excellence in Nanoscience, CAS Key Laboratory of Biomedical Effects of Nanomaterials and Nanosafety, National Center for Nanoscience and Technology Beijing 100190 P. R. China .,Sino-Danish College, University of Chinese Academy of Sciences Beijing 100049 P. R. China
| |
Collapse
|
45
|
Belsham HR, Friel CT. Identification of key residues that regulate the interaction of kinesins with microtubule ends. Cytoskeleton (Hoboken) 2019; 76:440-446. [PMID: 31574569 PMCID: PMC6899999 DOI: 10.1002/cm.21568] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 09/17/2019] [Accepted: 09/17/2019] [Indexed: 11/16/2022]
Abstract
Kinesins are molecular motors that use energy derived from ATP turnover to walk along microtubules, or when at the microtubule end, regulate growth or shrinkage. All kinesins that regulate microtubule dynamics have long residence times at microtubule ends, whereas those that only walk have short end‐residence times. Here, we identify key amino acids involved in end binding by showing that when critical residues from Kinesin‐13, which depolymerises microtubules, are introduced into Kinesin‐1, a walking kinesin with no effect on microtubule dynamics, the end‐residence time is increased up to several‐fold. This indicates that the interface between the kinesin motor domain and the microtubule is malleable and can be tuned to favour either lattice or end binding.
Collapse
Affiliation(s)
- Hannah R Belsham
- School of Life Sciences, University of Nottingham, Medical School, QMC, Nottingham, NG7 2UH, United Kingdom
| | - Claire T Friel
- School of Life Sciences, University of Nottingham, Medical School, QMC, Nottingham, NG7 2UH, United Kingdom
| |
Collapse
|
46
|
Phragmoplast Orienting Kinesin 2 Is a Weak Motor Switching between Processive and Diffusive Modes. Biophys J 2019; 115:375-385. [PMID: 30021112 DOI: 10.1016/j.bpj.2018.06.012] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 06/06/2018] [Accepted: 06/08/2018] [Indexed: 11/20/2022] Open
Abstract
Plant development and morphology relies on the accurate insertion of new cell walls during cytokinesis. However, how a plant cell correctly orients a new wall is poorly understood. Two kinesin class-12 members, phragmoplast orienting kinesin 1 (POK1) and POK2, are involved in the process, but how these molecular machines work is not known. Here, we used in vivo and single-molecule in vitro measurements to determine how Arabidopsis thaliana POK2 motors function mechanically. We found that POK2 is a very weak, on average plus-end-directed, moderately fast kinesin. Interestingly, POK2 switches between processive and diffusive modes characterized by an exclusive-state mean-squared-displacement analysis. Our results support a model that POK motors push against peripheral microtubules of the phragmoplast for its guidance. This pushing model may mechanically explain the conspicuous narrowing of the division site. Together, our findings provide mechanical insight into how active motors accurately position new cell walls in plants.
Collapse
|
47
|
Strothman C, Farmer V, Arpağ G, Rodgers N, Podolski M, Norris S, Ohi R, Zanic M. Microtubule minus-end stability is dictated by the tubulin off-rate. J Cell Biol 2019; 218:2841-2853. [PMID: 31420452 PMCID: PMC6719460 DOI: 10.1083/jcb.201905019] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 07/11/2019] [Accepted: 07/23/2019] [Indexed: 12/25/2022] Open
Abstract
Dynamic organization of microtubule minus ends is vital for the formation and maintenance of acentrosomal microtubule arrays. In vitro, both microtubule ends switch between phases of assembly and disassembly, a behavior called dynamic instability. Although minus ends grow slower, their lifetimes are similar to those of plus ends. The mechanisms underlying these distinct dynamics remain unknown. Here, we use an in vitro reconstitution approach to investigate minus-end dynamics. We find that minus-end lifetimes are not defined by the mean size of the protective GTP-tubulin cap. Rather, we conclude that the distinct tubulin off-rate is the primary determinant of the difference between plus- and minus-end dynamics. Further, our results show that the minus-end-directed kinesin-14 HSET/KIFC1 suppresses tubulin off-rate to specifically suppress minus-end catastrophe. HSET maintains its protective minus-end activity even when challenged by a known microtubule depolymerase, kinesin-13 MCAK. Our results provide novel insight into the mechanisms of minus-end dynamics, essential for our understanding of microtubule minus-end regulation in cells.
Collapse
Affiliation(s)
- Claire Strothman
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN
| | - Veronica Farmer
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN
| | - Göker Arpağ
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN
| | - Nicole Rodgers
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN
| | - Marija Podolski
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN
| | - Stephen Norris
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN
| | - Ryoma Ohi
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI
| | - Marija Zanic
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN
- Department of Biochemistry, Vanderbilt University, Nashville, TN
| |
Collapse
|
48
|
Lin TC, Kuo HH, Wu YC, Pan TS, Yih LH. Phosphatidylinositol-5-phosphate 4-kinase gamma accumulates at the spindle pole and prevents microtubule depolymerization. Cell Div 2019; 14:9. [PMID: 31452676 PMCID: PMC6702725 DOI: 10.1186/s13008-019-0053-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2019] [Accepted: 08/13/2019] [Indexed: 11/10/2022] Open
Abstract
Background A previous screen of a human kinase and phosphatase shRNA library to select genes that mediate arsenite induction of spindle abnormalities resulted in the identification of phosphatidylinositol-5-phosphate 4-kinase type-2 gamma (PIP4KIIγ), a phosphatidylinositol 4,5-bisphosphate (PIP2)-synthesizing enzyme. In this study, we explored how PIP4KIIγ regulates the assembly of mitotic spindles. Results PIP4KIIγ accumulates at the spindle pole before anaphase, and is required for the assembly of functional bipolar spindles. Depletion of PIP4KIIγ enhanced the spindle pole accumulation of mitotic centromere-associated kinesin (MCAK), a microtubule (MT)-depolymerizing kinesin, and resulted in a less stable spindle pole-associated MT. Depletion of MCAK can ameliorate PIP4KIIγ depletion-induced spindle abnormalities. In addition, PIP2 binds to polo-like kinase (PLK1) and reduces PLK1-mediated phosphorylation of MCAK. These results indicate that PIP4KIIγ and PIP2 may negatively regulate the MT depolymerization activity of MCAK by reducing PLK1-mediated phosphorylation of MCAK. Consequently, depletion of PLK1 has been shown to counteract the PIP4KIIγ depletion-induced instability of spindle pole-associated MT and cell resistance to arsenite. Conclusions Our current results imply that PIP4KIIγ may restrain MT depolymerization at the spindle pole through attenuating PLK1-mediated activation of MCAK before anaphase onset.
Collapse
Affiliation(s)
- Tz-Chi Lin
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, 115 Taiwan
| | - Hsiao-Hui Kuo
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, 115 Taiwan
| | - Yi-Chen Wu
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, 115 Taiwan
| | - Tiffany S Pan
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, 115 Taiwan
| | - Ling-Huei Yih
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, 115 Taiwan
| |
Collapse
|
49
|
Lacey SE, He S, Scheres SHW, Carter AP. Cryo-EM of dynein microtubule-binding domains shows how an axonemal dynein distorts the microtubule. eLife 2019; 8:e47145. [PMID: 31264960 PMCID: PMC6629372 DOI: 10.7554/elife.47145] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 07/01/2019] [Indexed: 01/14/2023] Open
Abstract
Dyneins are motor proteins responsible for transport in the cytoplasm and the beating of axonemes in cilia and flagella. They bind and release microtubules via a compact microtubule-binding domain (MTBD) at the end of a coiled-coil stalk. We address how cytoplasmic and axonemal dynein MTBDs bind microtubules at near atomic resolution. We decorated microtubules with MTBDs of cytoplasmic dynein-1 and axonemal dynein DNAH7 and determined their cryo-EM structures using helical Relion. The majority of the MTBD is rigid upon binding, with the transition to the high-affinity state controlled by the movement of a single helix at the MTBD interface. DNAH7 contains an 18-residue insertion, found in many axonemal dyneins, that contacts the adjacent protofilament. Unexpectedly, we observe that DNAH7, but not dynein-1, induces large distortions in the microtubule cross-sectional curvature. This raises the possibility that dynein coordination in axonemes is mediated via conformational changes in the microtubule.
Collapse
Affiliation(s)
- Samuel E Lacey
- MRC Laboratory of Molecular BiologyCambridgeUnited Kingdom
| | - Shaoda He
- MRC Laboratory of Molecular BiologyCambridgeUnited Kingdom
| | | | | |
Collapse
|
50
|
An estimate to the first approximation of microtubule rupture force. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2019; 48:569-577. [PMID: 31134309 DOI: 10.1007/s00249-019-01371-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 02/18/2019] [Accepted: 05/17/2019] [Indexed: 10/26/2022]
Abstract
Microtubule mechanical properties are essential for understanding basic cellular processes, including cell motility and division, but the forces that result in microtubule rupture or breakage have not yet been measured directly. These forces are essential to understand the mechanical properties of the cytoskeleton and responses by cells to both normal conditions and stress caused by injury or disease. Here we estimate the force required to rupture a microtubule by analyzing kinesin-14 Ncd motor-induced microtubule breakage in ensemble motility assays. We model the breakage events as caused by Ncd motors pulling or pushing on single microtubules that are clamped at one end by other motors attached to the glass surface. The number of pulling or pushing Ncd motors is approximated from the length of the microtubule bound to the surface and the forces produced by the pulling or pushing motors are estimated from forces produced by the Ncd motor in laser-trap assays, reported by others. Our analysis provides an estimate, to the first approximation, of ~ 500 pN for the minimal force required to rupture a 13-pf microtubule. The value we report is close to the forces estimated from microtubule stretching/fragmentation experiments and overlaps with the forces applied by AFM in microtubule indentation assays that destabilize microtubules and break microtubule protofilaments. It is also consistent with the forces required to disrupt protein noncovalent bonds in force spectroscopy experiments. These findings are relevant to microtubule deformation and breakage caused by cellular tension in vivo.
Collapse
|