1
|
McManus CT, Travis SM, Jeffrey PD, Zhang R, Petry S. Mechanism of how the universal module XMAP215 γ-TuRC nucleates microtubules. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.03.597159. [PMID: 38895418 PMCID: PMC11185565 DOI: 10.1101/2024.06.03.597159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/21/2024]
Abstract
It has become increasingly evident in recent years that nucleation of microtubules from a diverse set of MTOCs requires both the γ-tubulin ring complex (γ-TuRC) and the microtubule polymerase XMAP215. Despite their essentiality, little is known about how these nucleation factors interact and work together to generate microtubules. Using biochemical domain analysis of XMAP215 and structural approaches, we find that a sixth TOG domain in XMAP215 binds γ-TuRC via γ-tubulin as part of a broader interaction involving the C-terminal region. Moreover, TOG6 is required for XMAP215 to promote nucleation from γ-TuRC to its full extent. Interestingly, we find that XMAP215 also depends strongly on TOG5 for microtubule lattice binding and nucleation. Accordingly, we report a cryo-EM structure of TOG5 bound to the microtubule lattice that reveals promotion of lateral interactions between tubulin dimers. Finally, we find that while XMAP215 constructs' effects on nucleation are generally proportional to their effects on polymerization, formation of a direct complex with γ-TuRC allows cooperative nucleation activity. Thus, we propose that XMAP215's C-terminal TOGs 5 and 6 play key roles in promoting nucleation by promoting formation of longitudinal and lateral bonds in γ-TuRC templated nascent microtubules at cellular MTOCs.
Collapse
Affiliation(s)
- Collin T. McManus
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
| | - Sophie M. Travis
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
| | - Philip D. Jeffrey
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
| | - Rui Zhang
- Department of Biochemistry and Molecular Biophysics, Washington University in St. Louis, School of Medicine (St. Louis, Missouri, United States)
| | - Sabine Petry
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
| |
Collapse
|
2
|
Lakshmi RB, Nayak P, Raz L, Sarkar A, Saroha A, Kumari P, Nair VM, Kombarakkaran DP, Sajana S, M G S, Agasti SS, Paul R, Ben-David U, Manna TK. CKAP5 stabilizes CENP-E at kinetochores by regulating microtubule-chromosome attachments. EMBO Rep 2024; 25:1909-1935. [PMID: 38424231 PMCID: PMC11014917 DOI: 10.1038/s44319-024-00106-9] [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: 12/25/2023] [Revised: 02/02/2024] [Accepted: 02/12/2024] [Indexed: 03/02/2024] Open
Abstract
Stabilization of microtubule plus end-directed kinesin CENP-E at the metaphase kinetochores is important for chromosome alignment, but its mechanism remains unclear. Here, we show that CKAP5, a conserved microtubule plus tip protein, regulates CENP-E at kinetochores in human cells. Depletion of CKAP5 impairs CENP-E localization at kinetochores at the metaphase plate and results in increased kinetochore-microtubule stability and attachment errors. Erroneous attachments are also supported by computational modeling. Analysis of CKAP5 knockout cancer cells of multiple tissue origins shows that CKAP5 is preferentially essential in aneuploid, chromosomally unstable cells, and the sensitivity to CKAP5 depletion is correlated to that of CENP-E depletion. CKAP5 depletion leads to reduction in CENP-E-BubR1 interaction and the interaction is rescued by TOG4-TOG5 domain of CKAP5. The same domain can rescue CKAP5 depletion-induced CENP-E removal from the kinetochores. Interestingly, CKAP5 depletion facilitates recruitment of PP1 to the kinetochores and furthermore, a PP1 target site-specific CENP-E phospho-mimicking mutant gets stabilized at kinetochores in the CKAP5-depleted cells. Together, the results support a model in which CKAP5 controls mitotic chromosome attachment errors by stabilizing CENP-E at kinetochores and by regulating stability of the kinetochore-attached microtubules.
Collapse
Affiliation(s)
- R Bhagya Lakshmi
- School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram, Vithura, Thiruvananthapuram, Kerala, 695551, India
| | - Pinaki Nayak
- School of Mathematical and Computational Sciences, Indian Association for the Cultivation of Science, Jadavpur, Kolkata, 700032, India
| | - Linoy Raz
- Department of Human Molecular Genetics and Biochemistry, Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Apurba Sarkar
- School of Mathematical and Computational Sciences, Indian Association for the Cultivation of Science, Jadavpur, Kolkata, 700032, India
| | - Akshay Saroha
- New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, Karnataka, 560064, India
| | - Pratibha Kumari
- New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, Karnataka, 560064, India
| | - Vishnu M Nair
- School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram, Vithura, Thiruvananthapuram, Kerala, 695551, India
| | - Delvin P Kombarakkaran
- School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram, Vithura, Thiruvananthapuram, Kerala, 695551, India
| | - S Sajana
- School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram, Vithura, Thiruvananthapuram, Kerala, 695551, India
| | - Sanusha M G
- School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram, Vithura, Thiruvananthapuram, Kerala, 695551, India
| | - Sarit S Agasti
- New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, Karnataka, 560064, India
| | - Raja Paul
- School of Mathematical and Computational Sciences, Indian Association for the Cultivation of Science, Jadavpur, Kolkata, 700032, India
| | - Uri Ben-David
- Department of Human Molecular Genetics and Biochemistry, Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Tapas K Manna
- School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram, Vithura, Thiruvananthapuram, Kerala, 695551, India.
| |
Collapse
|
3
|
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
|
4
|
Marunaka Y. Physiological roles of chloride ions in bodily and cellular functions. J Physiol Sci 2023; 73:31. [PMID: 37968609 PMCID: PMC10717538 DOI: 10.1186/s12576-023-00889-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Accepted: 10/31/2023] [Indexed: 11/17/2023]
Abstract
Physiological roles of Cl-, a major anion in the body, are not well known compared with those of cations. This review article introduces: (1) roles of Cl- in bodily and cellular functions; (2) the range of cytosolic Cl- concentration ([Cl-]c); (3) whether [Cl-]c could change with cell volume change under an isosmotic condition; (4) whether [Cl-]c could change under conditions where multiple Cl- transporters and channels contribute to Cl- influx and efflux in an isosmotic state; (5) whether the change in [Cl-]c could be large enough to act as signals; (6) effects of Cl- on cytoskeletal tubulin polymerization through inhibition of GTPase activity and tubulin polymerization-dependent biological activity; (7) roles of cytosolic Cl- in cell proliferation; (8) Cl--regulatory mechanisms of ciliary motility; (9) roles of Cl- in sweet/umami taste receptors; (10) Cl--regulatory mechanisms of with-no-lysine kinase (WNK); (11) roles of Cl- in regulation of epithelial Na+ transport; (12) relationship between roles of Cl- and H+ in body functions.
Collapse
Affiliation(s)
- Yoshinori Marunaka
- Medical Research Institute, Kyoto Industrial Health Association, General Incorporated Foundation, 67 Kitatsuboi-Cho, Nishinokyo, Nakagyo-Ku, Kyoto, 604-8472, Japan.
- Research Organization of Science and Technology, Ritsumeikan University, Kusatsu, 525-8577, Japan.
- Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kamigyo-Ku, Kyoto, 602-8566, Japan.
| |
Collapse
|
5
|
Abstract
Higher-order or supramolecular protein assemblies, usually regulated by enzymatic reactions, are ubiquitous and essential for cellular functions. This evolutionary fact has provided a rigorous scientific foundation, as well as an inspiring blueprint, for exploring supramolecular assemblies of man-made molecules that are responsive to biological cues as a novel class of therapeutics for biomedicine. Among the emerging man-made supramolecular structures, peptide assemblies, formed by enzyme reactions or other stimuli, have received most of the research attention and advanced most rapidly.In this Account, we will review works that apply enzyme-instructed self-assembly (EISA) to generate intracellular peptide assemblies for developing a new kind of biomedicine, especially in the field of novel cancer nanomedicines and modulating cell morphogenesis. As a versatile and cell-compatible approach, EISA can generate nondiffusive peptide assemblies locally; thus, it provides a unique approach to target subcellular organelles with exceptional cell selectivity. We have arranged this Account in the following way: after introducing the concept, simplicity, and uniqueness of EISA, we discuss the EISA-formed intracellular peptide assemblies, including artificial filaments, in the cell cytosol. Then, we describe the representative examples targeting subcellular organelles, such as mitochondria, endoplasmic reticulum, Golgi apparatus, lysosomes, and the nucleus, by enzyme-instructed intracellular peptide assemblies for potential cancer therapeutics. After that, we highlight the recent exploration of the transcytosis of peptide assemblies for controlling cell morphogenesis. Finally, we provide a brief outlook of enzyme-instructed intracellular peptide assemblies. This Account aims to illustrate the promise of EISA-generated intracellular peptide assemblies in understanding diseases, controlling cell behaviors, and developing new therapeutics from a class of less explored molecular entities, which are substrates of enzymes and become building blocks of self-assembly after the enzymatic reactions.
Collapse
Affiliation(s)
- Zhiyu Liu
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, Massachusetts 02453, United States
| | - Jiaqi Guo
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, Massachusetts 02453, United States
| | - Yuchen Qiao
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, Massachusetts 02453, United States
| | - Bing Xu
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, Massachusetts 02453, United States
| |
Collapse
|
6
|
Zimyanin V, Magaj M, Yu CH, Gibney T, Mustafa B, Horton X, Siller K, Cueff L, Bouvrais H, Pécréaux J, Needleman D, Redemann S. Lack of chromokinesin Klp-19 creates a more rigid midzone and affects force transmission during anaphase in C. elegans. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.26.564275. [PMID: 37961478 PMCID: PMC10634869 DOI: 10.1101/2023.10.26.564275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
Recent studies have highlighted the significance of the spindle midzone - the region positioned between chromosomes - in ensuring proper chromosome segregation. By combining advanced 3D electron tomography and cutting-edge light microscopy we have discovered a previously unknown role of the regulation of microtubule dynamics within the spindle midzone of C. elegans. Using Fluorescence recovery after photobleaching and a combination of second harmonic generation and two-photon fluorescence microscopy, we found that the length of the antiparallel microtubule overlap zone in the spindle midzone is constant throughout anaphase, and independent of cortical pulling forces as well as the presence of the microtubule bundling protein SPD-1. Further investigations of SPD-1 and the chromokinesin KLP-19 in C. elegans suggest that KLP-19 regulates the overlap length and functions independently of SPD-1. Our data shows that KLP-19 plays an active role in regulating the length and turn-over of microtubules within the midzone as well as the size of the antiparallel overlap region throughout mitosis. Depletion of KLP-19 in mitosis leads to an increase in microtubule length in the spindle midzone, which also leads to increased microtubule - microtubule interaction, thus building up a more robust microtubule network. The spindle is globally stiffer and more stable, which has implications for the transmission of forces within the spindle affecting chromosome segregation dynamics. Our data shows that by localizing KLP-19 to the spindle midzone in anaphase microtubule dynamics can be locally controlled allowing the formation of a functional midzone.
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
| | - Magdalena Magaj
- Department of Molecular Physiology and Biological Physics, University of Virginia, School of Medicine, Charlottesville, VA, USA
- Department of Cell Biology, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Che-Hang Yu
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA, USA
| | - Theresa Gibney
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Basaran Mustafa
- Molecular and Cellular Biology and School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Xavier Horton
- Department of Molecular Physiology and Biological Physics, University of Virginia, School of Medicine, Charlottesville, VA, USA
- Department of Cell Biology, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Karsten Siller
- IT-Research Computing, University of Virginia, Charlottesville, VA, USA
| | - Louis Cueff
- CNRS, Univ Rennes, IGDR (Institut de Génétique et Dévelopement de Rennes) - UMR 6290, F-35000 Rennes, France
| | - Hélène Bouvrais
- CNRS, Univ Rennes, IGDR (Institut de Génétique et Dévelopement de Rennes) - UMR 6290, F-35000 Rennes, France
| | - Jacques Pécréaux
- CNRS, Univ Rennes, IGDR (Institut de Génétique et Dévelopement de Rennes) - UMR 6290, F-35000 Rennes, France
| | - Daniel Needleman
- Molecular and Cellular Biology and School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
- Center for Computational Biology, Flatiron Institute, New York, NY, 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
|
7
|
Quiogue AR, Sumiyoshi E, Fries A, Chuang CH, Bowerman B. Microtubules oppose cortical actomyosin-driven membrane ingression during C. elegans meiosis I polar body extrusion. PLoS Genet 2023; 19:e1010984. [PMID: 37782660 PMCID: PMC10569601 DOI: 10.1371/journal.pgen.1010984] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 10/12/2023] [Accepted: 09/19/2023] [Indexed: 10/04/2023] Open
Abstract
During C. elegans oocyte meiosis I cytokinesis and polar body extrusion, cortical actomyosin is locally remodeled to assemble a contractile ring that forms within and remains part of a much larger and actively contractile cortical actomyosin network. This network both mediates contractile ring dynamics and generates shallow ingressions throughout the oocyte cortex during polar body extrusion. Based on our analysis of requirements for CLS-2, a member of the CLASP family of proteins that stabilize microtubules, we recently proposed that a balance of actomyosin-mediated tension and microtubule-mediated stiffness limits membrane ingression throughout the oocyte during meiosis I polar body extrusion. Here, using live cell imaging and fluorescent protein fusions, we show that CLS-2 is part of a group of kinetochore proteins, including the scaffold KNL-1 and the kinase BUB-1, that also co-localize during meiosis I to structures called linear elements, which are present within the assembling oocyte spindle and also are distributed throughout the oocyte in proximity to, but appearing to underlie, the actomyosin cortex. We further show that KNL-1 and BUB-1, like CLS-2, promote the proper organization of sub-cortical microtubules and also limit membrane ingression throughout the oocyte. Moreover, nocodazole or taxol treatment to destabilize or stabilize oocyte microtubules leads to, respectively, excess or decreased membrane ingression throughout the oocyte. Furthermore, taxol treatment, and genetic backgrounds that elevate the levels of cortically associated microtubules, both suppress excess membrane ingression in cls-2 mutant oocytes. We propose that linear elements influence the organization of sub-cortical microtubules to generate a stiffness that limits cortical actomyosin-driven membrane ingression throughout the oocyte during meiosis I polar body extrusion. We discuss the possibility that this regulation of sub-cortical microtubule dynamics facilitates actomyosin contractile ring dynamics during C. elegans oocyte meiosis I cell division.
Collapse
Affiliation(s)
- Alyssa R. Quiogue
- Institute of Molecular Biology, University of Oregon, Eugen, Oregon, United States of America
| | - Eisuke Sumiyoshi
- Institute of Molecular Biology, University of Oregon, Eugen, Oregon, United States of America
| | - Adam Fries
- Institute of Molecular Biology, University of Oregon, Eugen, Oregon, United States of America
- Imaging Core, Office of the Vice President for Research University of Oregon, Eugene, Oregon, United States of America
| | - Chien-Hui Chuang
- Institute of Molecular Biology, University of Oregon, Eugen, Oregon, United States of America
| | - Bruce Bowerman
- Institute of Molecular Biology, University of Oregon, Eugen, Oregon, United States of America
| |
Collapse
|
8
|
Lawrence EJ, Chatterjee S, Zanic M. CLASPs stabilize the pre-catastrophe intermediate state between microtubule growth and shrinkage. J Cell Biol 2023; 222:e202107027. [PMID: 37184584 PMCID: PMC10195879 DOI: 10.1083/jcb.202107027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 12/03/2022] [Accepted: 04/18/2023] [Indexed: 05/16/2023] Open
Abstract
Cytoplasmic linker-associated proteins (CLASPs) regulate microtubules in fundamental cellular processes. CLASPs stabilize dynamic microtubules by suppressing microtubule catastrophe and promoting rescue, the switch-like transitions between growth and shrinkage. How CLASPs specifically modulate microtubule transitions is not understood. Here, we investigate the effects of CLASPs on the pre-catastrophe intermediate state of microtubule dynamics, employing distinct microtubule substrates to mimic the intermediate state. Surprisingly, we find that CLASP1 promotes the depolymerization of stabilized microtubules in the presence of GTP, but not in the absence of nucleotide. This activity is also observed for CLASP2 family members and a minimal TOG2-domain construct. Conversely, we find that CLASP1 stabilizes unstable microtubules upon tubulin dilution in the presence of GTP. Strikingly, our results reveal that CLASP1 drives microtubule substrates with vastly different inherent stabilities into the same slowly depolymerizing state in a nucleotide-dependent manner. We interpret this state as the pre-catastrophe intermediate state. Therefore, we conclude that CLASPs suppress microtubule catastrophe by stabilizing the intermediate state between growth and shrinkage.
Collapse
Affiliation(s)
- Elizabeth J. Lawrence
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN, USA
| | - Saptarshi Chatterjee
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN, USA
| | - Marija Zanic
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN, USA
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN, USA
- Department of Biochemistry, Vanderbilt University, Nashville, TN, USA
| |
Collapse
|
9
|
Ansari S, Gergely ZR, Flynn P, Li G, Moore JK, Betterton MD. Quantifying Yeast Microtubules and Spindles Using the Toolkit for Automated Microtubule Tracking (TAMiT). Biomolecules 2023; 13:939. [PMID: 37371519 DOI: 10.3390/biom13060939] [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: 07/28/2022] [Revised: 02/07/2023] [Accepted: 02/09/2023] [Indexed: 06/29/2023] Open
Abstract
Fluorescently labeled proteins absorb and emit light, appearing as Gaussian spots in fluorescence imaging. When fluorescent tags are added to cytoskeletal polymers such as microtubules, a line of fluorescence and even non-linear structures results. While much progress has been made in techniques for imaging and microscopy, image analysis is less well-developed. Current analysis of fluorescent microtubules uses either manual tools, such as kymographs, or automated software. As a result, our ability to quantify microtubule dynamics and organization from light microscopy remains limited. Despite the development of automated microtubule analysis tools for in vitro studies, analysis of images from cells often depends heavily on manual analysis. One of the main reasons for this disparity is the low signal-to-noise ratio in cells, where background fluorescence is typically higher than in reconstituted systems. Here, we present the Toolkit for Automated Microtubule Tracking (TAMiT), which automatically detects, optimizes, and tracks fluorescent microtubules in living yeast cells with sub-pixel accuracy. Using basic information about microtubule organization, TAMiT detects linear and curved polymers using a geometrical scanning technique. Images are fit via an optimization problem for the microtubule image parameters that are solved using non-linear least squares in Matlab. We benchmark our software using simulated images and show that it reliably detects microtubules, even at low signal-to-noise ratios. Then, we use TAMiT to measure monopolar spindle microtubule bundle number, length, and lifetime in a large dataset that includes several S. pombe mutants that affect microtubule dynamics and bundling. The results from the automated analysis are consistent with previous work and suggest a direct role for CLASP/Cls1 in bundling spindle microtubules. We also illustrate automated tracking of single curved astral microtubules in S. cerevisiae, with measurement of dynamic instability parameters. The results obtained with our fully-automated software are similar to results using hand-tracked measurements. Therefore, TAMiT can facilitate automated analysis of spindle and microtubule dynamics in yeast cells.
Collapse
Affiliation(s)
- Saad Ansari
- Department of Physics, University of Colorado Boulder, Boulder, CO 80309, USA
| | - Zachary R Gergely
- Department of Physics, University of Colorado Boulder, Boulder, CO 80309, USA
- Department of Molecular, Cellular and Developmental Biology, University of Colorado Boulder, Boulder, CO 80309, USA
| | - Patrick Flynn
- Department of Physics, University of Colorado Boulder, Boulder, CO 80309, USA
| | - Gabriella Li
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Jeffrey K Moore
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Meredith D Betterton
- Department of Physics, University of Colorado Boulder, Boulder, CO 80309, USA
- Department of Molecular, Cellular and Developmental Biology, University of Colorado Boulder, Boulder, CO 80309, USA
| |
Collapse
|
10
|
Quiogue AR, Sumiyoshi E, Fries A, Chuang CH, Bowerman B. Cortical microtubules oppose actomyosin-driven membrane ingression during C. elegans meiosis I polar body extrusion. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.26.542508. [PMID: 37292632 PMCID: PMC10245968 DOI: 10.1101/2023.05.26.542508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
During C. elegans oocyte meiosis I, cortical actomyosin is locally remodeled to assemble a contractile ring near the spindle. In contrast to mitosis, when most cortical actomyosin converges into a contractile ring, the small oocyte ring forms within and remains part of a much larger and actively contractile cortical actomyosin network. This network both mediates contractile ring dynamics and generates shallow ingressions throughout the oocyte cortex during polar body extrusion. Based on our analysis of requirements for CLS-2, a member of the CLASP family of proteins that stabilize microtubules, we recently proposed that a balance of actomyosin-mediated tension and microtubule-mediated stiffness are required for contractile ring assembly within the oocyte cortical actomyosin network. Here, using live cell imaging and fluorescent protein fusions, we show that CLS-2 is part of a complex of kinetochore proteins, including the scaffold KNL-1 and the kinase BUB-1, that also co-localize to patches distributed throughout the oocyte cortex during meiosis I. By reducing their function, we further show that KNL-1 and BUB-1, like CLS-2, are required for cortical microtubule stability, to limit membrane ingression throughout the oocyte, and for meiotic contractile ring assembly and polar body extrusion. Moreover, nocodazole or taxol treatment to destabilize or stabilize oocyte microtubules, respectively, leads to excess or decreased membrane ingression throughout the oocyte and defective polar body extrusion. Finally, genetic backgrounds that elevate cortical microtubule levels suppress the excess membrane ingression in cls-2 mutant oocytes. These results support our hypothesis that CLS-2, as part of a sub-complex of kinetochore proteins that also co-localize to patches throughout the oocyte cortex, stabilizes microtubules to stiffen the oocyte cortex and limit membrane ingression throughout the oocyte, thereby facilitating contractile ring dynamics and the successful completion of polar body extrusion during meiosis I.
Collapse
Affiliation(s)
| | | | - Adam Fries
- Institute of Molecular Biology
- Imaging Core, Office of the Vice President for Research, University of Oregon, Eugene, OR USA 97403
| | | | | |
Collapse
|
11
|
Macaisne N, Bellutti L, Laband K, Edwards F, Pitayu-Nugroho L, Gervais A, Ganeswaran T, Geoffroy H, Maton G, Canman JC, Lacroix B, Dumont J. Synergistic stabilization of microtubules by BUB-1, HCP-1, and CLS-2 controls microtubule pausing and meiotic spindle assembly. eLife 2023; 12:e82579. [PMID: 36799894 PMCID: PMC10005782 DOI: 10.7554/elife.82579] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 02/16/2023] [Indexed: 02/18/2023] Open
Abstract
During cell division, chromosome segregation is orchestrated by a microtubule-based spindle. Interaction between spindle microtubules and kinetochores is central to the bi-orientation of chromosomes. Initially dynamic to allow spindle assembly and kinetochore attachments, which is essential for chromosome alignment, microtubules are eventually stabilized for efficient segregation of sister chromatids and homologous chromosomes during mitosis and meiosis I, respectively. Therefore, the precise control of microtubule dynamics is of utmost importance during mitosis and meiosis. Here, we study the assembly and role of a kinetochore module, comprised of the kinase BUB-1, the two redundant CENP-F orthologs HCP-1/2, and the CLASP family member CLS-2 (hereafter termed the BHC module), in the control of microtubule dynamics in Caenorhabditis elegans oocytes. Using a combination of in vivo structure-function analyses of BHC components and in vitro microtubule-based assays, we show that BHC components stabilize microtubules, which is essential for meiotic spindle formation and accurate chromosome segregation. Overall, our results show that BUB-1 and HCP-1/2 do not only act as targeting components for CLS-2 at kinetochores, but also synergistically control kinetochore-microtubule dynamics by promoting microtubule pause. Together, our results suggest that BUB-1 and HCP-1/2 actively participate in the control of kinetochore-microtubule dynamics in the context of an intact BHC module to promote spindle assembly and accurate chromosome segregation in meiosis.
Collapse
Affiliation(s)
- Nicolas Macaisne
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013ParisFrance
| | - Laura Bellutti
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013ParisFrance
| | - Kimberley Laband
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013ParisFrance
| | - Frances Edwards
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013ParisFrance
| | | | - Alison Gervais
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013ParisFrance
| | | | - Hélène Geoffroy
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013ParisFrance
| | - Gilliane Maton
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013ParisFrance
| | - Julie C Canman
- Columbia University; Department of Pathology and Cell BiologyNew YorkUnited States
| | - Benjamin Lacroix
- Centre de Recherche en Biologie Cellulaire de Montpellier (CRBM), CNRS UMR 5237, Université de MontpellierMontpellierFrance
| | - Julien Dumont
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013ParisFrance
| |
Collapse
|
12
|
Ansari S, Gergely ZR, Flynn P, Li G, Moore JK, Betterton MD. Quantifying yeast microtubules and spindles using the Toolkit for Automated Microtubule Tracking (TAMiT). BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.07.527544. [PMID: 36798368 PMCID: PMC9934621 DOI: 10.1101/2023.02.07.527544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Fluorescently labeled proteins absorb and emit light, appearing as Gaussian spots in fluorescence imaging. When fluorescent tags are added to cytoskeletal polymers such as microtubules, a line of fluorescence and even non-linear structures results. While much progress has been made in techniques for imaging and microscopy, image analysis is less well developed. Current analysis of fluorescent microtubules uses either manual tools, such as kymographs, or automated software. As a result, our ability to quantify microtubule dynamics and organization from light microscopy remains limited. Despite development of automated microtubule analysis tools for in vitro studies, analysis of images from cells often depends heavily on manual analysis. One of the main reasons for this disparity is the low signal-to-noise ratio in cells, where background fluorescence is typically higher than in reconstituted systems. Here, we present the Toolkit for Automated Microtubule Tracking (TAMiT), which automatically detects, optimizes and tracks fluorescent microtubules in living yeast cells with sub-pixel accuracy. Using basic information about microtubule organization, TAMiT detects linear and curved polymers using a geometrical scanning technique. Images are fit via an optimization problem for the microtubule image parameters that is solved using non-linear least squares in Matlab. We benchmark our software using simulated images and show that it reliably detects microtubules, even at low signal-to-noise ratios. Then, we use TAMiT to measure monopolar spindle microtubule bundle number, length, and lifetime in a large dataset that includes several S. pombe mutants that affect microtubule dynamics and bundling. The results from the automated analysis are consistent with previous work, and suggest a direct role for CLASP/Cls1 in bundling spindle microtubules. We also illustrate automated tracking of single curved astral microtubules in S. cerevisiae , with measurement of dynamic instability parameters. The results obtained with our fully-automated software are similar to results using hand-tracked measurements. Therefore, TAMiT can facilitate automated analysis of spindle and microtubule dynamics in yeast cells.
Collapse
|
13
|
Farmer VJ, Zanic M. Beyond the GTP-cap: Elucidating the molecular mechanisms of microtubule catastrophe. Bioessays 2023; 45:e2200081. [PMID: 36398561 PMCID: PMC10648283 DOI: 10.1002/bies.202200081] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 11/03/2022] [Accepted: 11/04/2022] [Indexed: 11/19/2022]
Abstract
Almost 40 years since the discovery of microtubule dynamic instability, the molecular mechanisms underlying microtubule dynamics remain an area of intense research interest. The "standard model" of microtubule dynamics implicates a "cap" of GTP-bound tubulin dimers at the growing microtubule end as the main determinant of microtubule stability. Loss of the GTP-cap leads to microtubule "catastrophe," a switch-like transition from microtubule growth to shrinkage. However, recent studies, using biochemical in vitro reconstitution, cryo-EM, and computational modeling approaches, challenge the simple GTP-cap model. Instead, a new perspective on the mechanisms of microtubule dynamics is emerging. In this view, highly dynamic transitions between different structural conformations of the growing microtubule end - which may or may not be directly linked to the nucleotide content at the microtubule end - ultimately drive microtubule catastrophe.
Collapse
Affiliation(s)
- Veronica J. Farmer
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee, USA
| | - Marija Zanic
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee, USA
- Department of Biomolecular and Chemical Engineering, Department of Biochemistry, Vanderbilt University, Nashville, Tennessee, USA
| |
Collapse
|
14
|
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
|
15
|
Cushion TD, Leca I, Keays DA. MAPping tubulin mutations. Front Cell Dev Biol 2023; 11:1136699. [PMID: 36875768 PMCID: PMC9975266 DOI: 10.3389/fcell.2023.1136699] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 02/02/2023] [Indexed: 02/17/2023] Open
Abstract
Microtubules are filamentous structures that play a critical role in a diverse array of cellular functions including, mitosis, nuclear translocation, trafficking of organelles and cell shape. They are composed of α/β-tubulin heterodimers which are encoded by a large multigene family that has been implicated in an umbrella of disease states collectively known as the tubulinopathies. De novo mutations in different tubulin genes are known to cause lissencephaly, microcephaly, polymicrogyria, motor neuron disease, and female infertility. The diverse clinical features associated with these maladies have been attributed to the expression pattern of individual tubulin genes, as well as their distinct Functional repertoire. Recent studies, however, have highlighted the impact of tubulin mutations on microtubule-associated proteins (MAPs). MAPs can be classified according to their effect on microtubules and include polymer stabilizers (e.g., tau, MAP2, doublecortin), destabilizers (e.g., spastin, katanin), plus-end binding proteins (e.g., EB1-3, XMAP215, CLASPs) and motor proteins (e.g., dyneins, kinesins). In this review we analyse mutation-specific disease mechanisms that influence MAP binding and their phenotypic consequences, and discuss methods by which we can exploit genetic variation to identify novel MAPs.
Collapse
Affiliation(s)
- Thomas D Cushion
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom.,Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
| | - Ines Leca
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
| | - David A Keays
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom.,Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria.,Division of Neurobiology, Department Biology II, Ludwig-Maximilians-University Munich, Munich, Germany
| |
Collapse
|
16
|
Harvey AM, Chuang CH, Sumiyoshi E, Bowerman B. C. elegans XMAP215/ZYG-9 and TACC/TAC-1 act at multiple times during oocyte meiotic spindle assembly and promote both spindle pole coalescence and stability. PLoS Genet 2023; 19:e1010363. [PMID: 36608115 PMCID: PMC9851561 DOI: 10.1371/journal.pgen.1010363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 01/19/2023] [Accepted: 12/13/2022] [Indexed: 01/09/2023] Open
Abstract
The conserved two-component XMAP215/TACC modulator of microtubule stability is required in multiple animal phyla for acentrosomal spindle assembly during oocyte meiotic cell division. In C. elegans, XMAP215/zyg-9 and TACC/tac-1 mutant oocytes exhibit multiple and indistinguishable oocyte spindle assembly defects beginning early in meiosis I. To determine if these defects represent one or more early requirements with additional later and indirect consequences, or multiple temporally distinct and more direct requirements, we have used live cell imaging and fast-acting temperature-sensitive zyg-9 and tac-1 alleles to dissect their requirements at high temporal resolution. Temperature upshift and downshift experiments indicate that the ZYG-9/TAC-1 complex has multiple temporally distinct and separable requirements throughout oocyte meiotic cell division. First, we show that during prometaphase ZYG-9 and TAC-1 promote the coalescence of early pole foci into a bipolar structure, stabilizing pole foci as they grow and limiting their growth rate, with these requirements being independent of an earlier defect in microtubule organization that occurs upon nuclear envelope breakdown. Second, during metaphase, ZYG-9 and TAC-1 maintain spindle bipolarity by suppressing ectopic pole formation. Third, we show that ZYG-9 and TAC-1 also are required for spindle assembly during meiosis II, independently of their meiosis I requirements. The metaphase pole stability requirement appears to be important for maintaining chromosome congression, and we discuss how negative regulation of microtubule stability by ZYG-9/TAC-1 during oocyte meiotic cell division might account for the observed defects in spindle pole coalescence and stability.
Collapse
Affiliation(s)
- Austin M. Harvey
- Institute of Molecular Biology, University of Oregon, Eugene, Oregon, United States of America
| | - Chien-Hui Chuang
- Institute of Molecular Biology, University of Oregon, Eugene, Oregon, United States of America
| | - Eisuke Sumiyoshi
- Institute of Molecular Biology, University of Oregon, Eugene, Oregon, United States of America
| | - Bruce Bowerman
- Institute of Molecular Biology, University of Oregon, Eugene, Oregon, United States of America
| |
Collapse
|
17
|
Murase Y, Yamagishi M, Okada N, Toya M, Yajima J, Hamada T, Sato M. Fission yeast Dis1 is an unconventional TOG/XMAP215 that induces microtubule catastrophe to drive chromosome pulling. Commun Biol 2022; 5:1298. [PMID: 36435910 PMCID: PMC9701203 DOI: 10.1038/s42003-022-04271-2] [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: 08/05/2022] [Accepted: 11/16/2022] [Indexed: 11/28/2022] Open
Abstract
The shortening of microtubules attached to kinetochores is the driving force of chromosome movement during cell division. Specific kinesins are believed to shorten microtubules but are dispensable for viability in yeast, implying the existence of additional factors responsible for microtubule shortening. Here, we demonstrate that Dis1, a TOG/XMAP215 ortholog in fission yeast, promotes microtubule shortening to carry chromosomes. Although TOG/XMAP215 orthologs are generally accepted as microtubule polymerases, Dis1 promoted microtubule catastrophe in vitro and in vivo. Notably, microtubule catastrophe was promoted when the tip was attached to kinetochores, as they steadily anchored Dis1 at the kinetochore-microtubule interface. Engineered Dis1 oligomers artificially tethered at a chromosome arm region induced the shortening of microtubules in contact, frequently pulling the chromosome arm towards spindle poles. This effect was not brought by oligomerised Alp14. Thus, unlike Alp14 and other TOG/XMAP215 orthologs, Dis1 plays an unconventional role in promoting microtubule catastrophe, thereby driving chromosome movement.
Collapse
Affiliation(s)
- Yuichi Murase
- grid.5290.e0000 0004 1936 9975Laboratory of Cytoskeletal Logistics, Department of Life Science and Medical Bioscience, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsucho, Shinjuku-ku, Tokyo 162-8480 Japan
| | - Masahiko Yamagishi
- grid.26999.3d0000 0001 2151 536XDepartment of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, 153-8902 Tokyo Japan
| | - Naoyuki Okada
- grid.5290.e0000 0004 1936 9975Laboratory of Cytoskeletal Logistics, Department of Life Science and Medical Bioscience, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsucho, Shinjuku-ku, Tokyo 162-8480 Japan ,grid.5808.50000 0001 1503 7226Instituto de Biologia Molecular e Celular, Instituto de Investigacao e Inovacao em Saude (i3S), Universidade do Porto, 208 Rua Alfredo Allen, 4200-135 Porto, Portugal
| | - Mika Toya
- grid.5290.e0000 0004 1936 9975Laboratory of Cytoskeletal Logistics, Department of Life Science and Medical Bioscience, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsucho, Shinjuku-ku, Tokyo 162-8480 Japan ,grid.5290.e0000 0004 1936 9975Global Center for Science and Engineering, Faculty of Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo 169-8555 Japan ,grid.5290.e0000 0004 1936 9975Institute for Advanced Research of Biosystem Dynamics, Waseda Research Institute for Science and Engineering, Graduate School of Advanced Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo 169-8555 Japan
| | - Junichiro Yajima
- grid.26999.3d0000 0001 2151 536XDepartment of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, 153-8902 Tokyo Japan ,grid.26999.3d0000 0001 2151 536XKomaba Institute for Science, The University of Tokyo, 3-8-1, Komaba, Meguro-ku, 153-8902 Tokyo Japan ,grid.26999.3d0000 0001 2151 536XResearch Center for Complex Systems Biology, The University of Tokyo, 3-8-1, Komaba, Meguro-ku, 153-8902 Tokyo Japan
| | - Takahiro Hamada
- grid.444568.f0000 0001 0672 2184Department of Bioscience, Faculty of Life Science, Okayama University of Science, 1-1 Ridaicho, Kita-ku, Okayama-shi 700-0005 Japan
| | - Masamitsu Sato
- grid.5290.e0000 0004 1936 9975Laboratory of Cytoskeletal Logistics, Department of Life Science and Medical Bioscience, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsucho, Shinjuku-ku, Tokyo 162-8480 Japan ,grid.5290.e0000 0004 1936 9975Institute for Advanced Research of Biosystem Dynamics, Waseda Research Institute for Science and Engineering, Graduate School of Advanced Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo 169-8555 Japan ,grid.5290.e0000 0004 1936 9975Institute for Medical-Oriented Structural Biology, Waseda University, 2-2 Wakamatsucho, Shinjuku-ku, Tokyo 162-8480 Japan
| |
Collapse
|
18
|
The TOG protein Stu2 is regulated by acetylation. PLoS Genet 2022; 18:e1010358. [PMID: 36084134 PMCID: PMC9491610 DOI: 10.1371/journal.pgen.1010358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 09/21/2022] [Accepted: 07/27/2022] [Indexed: 11/27/2022] Open
Abstract
Stu2 in S. cerevisiae is a member of the XMAP215/Dis1/CKAP5/ch-TOG family of MAPs and has multiple functions in controlling microtubules, including microtubule polymerization, microtubule depolymerization, linking chromosomes to the kinetochore, and assembly of γ-TuSCs at the SPB. Whereas phosphorylation has been shown to be critical for Stu2 localization at the kinetochore, other regulatory mechanisms that control Stu2 function are still poorly understood. Here, we show that a novel form of Stu2 regulation occurs through the acetylation of three lysine residues at K252, K469, and K870, which are located in three distinct domains of Stu2. Alteration of acetylation through acetyl-mimetic and acetyl-blocking mutations did not impact the essential function of Stu2. Instead, these mutations lead to a decrease in chromosome stability, as well as changes in resistance to the microtubule depolymerization drug, benomyl. In agreement with our in silico modeling, several acetylation-mimetic mutants displayed increased interactions with γ-tubulin. Taken together, these data suggest that Stu2 acetylation can govern multiple Stu2 functions, including chromosome stability and interactions at the SPB. Microtubules are proteinaceous polymers that play several important roles in cell division and segregation of the genetic material to each daughter cell. The functions of microtubules are critically dependent upon their dynamic properties in which tubulin subunits are added or removed from the microtubule end, allowing microtubules to grow or shorten in length. These dynamic properties are controlled by several types of microtubule associated proteins. In this study using bakers yeast, we describe our discovery of a previously unappreciated way to regulate the microtubule associated protein Stu2 by a modification called acetylation. When we created mutations in the Stu2 protein that can’t be properly acetylated, the cell lost some of its chromosomes. Some of these mutations actually caused the microtubules to be resistant to drugs that normally disassemble the microtubule polymer. As similar versions of the Stu2 protein are found in diverse organisms that range from yeast and fungus, to plants, insects, mammals and humans, our work could provide unique insights into how microtubules malfunction in some human diseases. With further studies, this may provide a new understanding of chromosome loss in birth defects and/or cancer.
Collapse
|
19
|
Chen Y, Liu X, Zhang W, Li J, Liu H, Yang L, Lei P, Zhang H, Yu F. MOR1/MAP215 acts synergistically with katanin to control cell division and anisotropic cell elongation in Arabidopsis. THE PLANT CELL 2022; 34:3006-3027. [PMID: 35579372 PMCID: PMC9373954 DOI: 10.1093/plcell/koac147] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 05/07/2022] [Indexed: 05/20/2023]
Abstract
The MAP215 family of microtubule (MT) polymerase/nucleation factors and the MT severing enzyme katanin are widely conserved MT-associated proteins (MAPs) across the plant and animal kingdoms. However, how these two essential MAPs coordinate to regulate plant MT dynamics and development remains unknown. Here, we identified novel hypomorphic alleles of MICROTUBULE ORGANIZATION 1 (MOR1), encoding the Arabidopsis thaliana homolog of MAP215, in genetic screens for mutants oversensitive to the MT-destabilizing drug propyzamide. Live imaging in planta revealed that MOR1-green fluorescent protein predominantly tracks the plus-ends of cortical MTs (cMTs) in interphase cells and labels preprophase band, spindle and phragmoplast MT arrays in dividing cells. Remarkably, MOR1 and KATANIN 1 (KTN1), the p60 subunit of Arabidopsis katanin, act synergistically to control the proper formation of plant-specific MT arrays, and consequently, cell division and anisotropic cell expansion. Moreover, MOR1 physically interacts with KTN1 and promotes KTN1-mediated severing of cMTs. Our work establishes the Arabidopsis MOR1-KTN1 interaction as a central functional node dictating MT dynamics and plant growth and development.
Collapse
Affiliation(s)
| | | | - Wenjing Zhang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Jie Li
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Haofeng Liu
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Lan Yang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Pei Lei
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Hongchang Zhang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Fei Yu
- Author for correspondence:
| |
Collapse
|
20
|
Yunes SA, Willoughby JLS, Kwan JH, Biagi JM, Pokharel N, Chin HG, York EA, Su KC, George K, Shah JV, Emili A, Schaus SE, Hansen U. Factor quinolinone inhibitors disrupt spindles and multiple LSF (TFCP2)-protein interactions in mitosis, including with microtubule-associated proteins. PLoS One 2022; 17:e0268857. [PMID: 35704642 PMCID: PMC9200292 DOI: 10.1371/journal.pone.0268857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 05/09/2022] [Indexed: 11/19/2022] Open
Abstract
Factor quinolinone inhibitors (FQIs), a first-in-class set of small molecule inhibitors targeted to the transcription factor LSF (TFCP2), exhibit promising cancer chemotherapeutic properties. FQI1, the initial lead compound identified, unexpectedly induced a concentration-dependent delay in mitotic progression. Here, we show that FQI1 can rapidly and reversibly lead to mitotic arrest, even when added directly to mitotic cells, implying that FQI1-mediated mitotic defects are not transcriptionally based. Furthermore, treatment with FQIs resulted in a striking, concentration-dependent diminishment of spindle microtubules, accompanied by a concentration-dependent increase in multi-aster formation. Aberrant γ-tubulin localization was also observed. These phenotypes suggest that perturbation of spindle microtubules is the primary event leading to the mitotic delays upon FQI1 treatment. Previously, FQIs were shown to specifically inhibit not only LSF DNA-binding activity, which requires LSF oligomerization to tetramers, but also other specific LSF-protein interactions. Other transcription factors participate in mitosis through non-transcriptional means, and we recently reported that LSF directly binds α-tubulin and is present in purified cellular tubulin preparations. Consistent with a microtubule role for LSF, here we show that LSF enhanced the rate of tubulin polymerization in vitro, and FQI1 inhibited such polymerization. To probe whether the FQI1-mediated spindle abnormalities could result from inhibition of mitotic LSF-protein interactions, mass spectrometry was performed using as bait an inducible, tagged form of LSF that is biotinylated by endogenous enzymes. The global proteomics analysis yielded expected associations for a transcription factor, notably with RNA processing machinery, but also to nontranscriptional components. In particular, and consistent with spindle disruption due to FQI treatment, mitotic, FQI1-sensitive interactions were identified between the biotinylated LSF and microtubule-associated proteins that regulate spindle assembly, positioning, and dynamics, as well as centrosome-associated proteins. Probing the mitotic LSF interactome using small molecule inhibitors therefore supported a non-transcriptional role for LSF in mediating progression through mitosis.
Collapse
Affiliation(s)
- Sarah A. Yunes
- Department of Biology, Boston University, Boston, Massachusetts, United States of America
- Program in Molecular Biology, Cell Biology, and Biochemistry, Boston University, Boston, Massachusetts, United States of America
| | - Jennifer L. S. Willoughby
- Program in Molecular Biology, Cell Biology, and Biochemistry, Boston University, Boston, Massachusetts, United States of America
- Alnylam Pharmaceuticals, Cambridge, Massachusetts, United States of America
| | - Julian H. Kwan
- Department of Biochemistry and Center for Network Systems Biology, Boston University School of Medicine, Boston, Massachusetts, United States of America
| | - Jessica M. Biagi
- Department of Chemistry and Center for Molecular Discovery, Boston University, Boston, Massachusetts, United States of America
| | - Niranjana Pokharel
- Department of Chemistry and Center for Molecular Discovery, Boston University, Boston, Massachusetts, United States of America
| | - Hang Gyeong Chin
- Program in Molecular Biology, Cell Biology, and Biochemistry, Boston University, Boston, Massachusetts, United States of America
- New England Biolabs, Ipswich, Massachusetts, United States of America
| | - Emily A. York
- Department of Chemistry and Center for Molecular Discovery, Boston University, Boston, Massachusetts, United States of America
| | - Kuan-Chung Su
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, United States of America
| | - Kelly George
- Department of Systems Biology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Jagesh V. Shah
- Department of Systems Biology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Andrew Emili
- Department of Biology, Boston University, Boston, Massachusetts, United States of America
- Department of Biochemistry and Center for Network Systems Biology, Boston University School of Medicine, Boston, Massachusetts, United States of America
| | - Scott E. Schaus
- Department of Chemistry and Center for Molecular Discovery, Boston University, Boston, Massachusetts, United States of America
| | - Ulla Hansen
- Department of Biology, Boston University, Boston, Massachusetts, United States of America
- Program in Molecular Biology, Cell Biology, and Biochemistry, Boston University, Boston, Massachusetts, United States of America
| |
Collapse
|
21
|
Zhang L, Ambrose C. CLASP balances two competing cell division plane cues during leaf development. NATURE PLANTS 2022; 8:682-693. [PMID: 35668154 DOI: 10.1038/s41477-022-01163-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 05/04/2022] [Indexed: 06/15/2023]
Abstract
Starting as small, densely packed boxes, leaf mesophyll cells expand to form an intricate mesh of interconnected cells and air spaces, the organization of which dictates the internal surface area of the leaf for light capture and gas exchange during photosynthesis. Despite their importance, little is known about the basic patterns of mesophyll cell division, and how they contribute to cell and intercellular space organization. To address this, we tracked divisions within individual cell lineages in three dimensions over time in Arabidopsis spongy mesophyll. We found that early on, successive cell division planes switch their orientation such that each new cell wall intersects the previous at a right angle, creating a new multi-cell junction (the intersection of three or more cells). These junctions then open to create intercellular spaces. During subsequent enlargement of the spaces, the division planes of the surrounding cells show an increasing tendency to tilt in the direction of their adjacent intercellular spaces. This disrupts the alternating pattern, and by extension, halts the initiation of new multi-cell junctions and intercellular spaces, but allows the expansion of existing spaces. Both division patterns are specified before mitosis by the orientation of interphase cortical microtubules, which gradually narrow to form a preprophase band in the same orientation to establish the future plane of cell division. In the absence of the microtubule-associated protein CLASP, the early alternating division plane and microtubule patterns are compromised, whereas space-oriented divisions are exacerbated. This results in large distortions of the topological relations between cells and intercellular spaces, as well as changes in their relative abundance. Our data reveal the existence of two competing cell division mechanisms that are balanced by CLASP to specify the distribution of cells and intercellular spaces in spongy mesophyll tissue.
Collapse
Affiliation(s)
- Liyong Zhang
- Department of Biology, The University of Saskatchewan, College of Arts and Science, Saskatoon, Saskatchewan, Canada
| | - Chris Ambrose
- Department of Biology, The University of Saskatchewan, College of Arts and Science, Saskatoon, Saskatchewan, Canada.
| |
Collapse
|
22
|
Bu S, Tang Q, Wang Y, Lau SSY, Yong WL, Yu F. Drosophila CLASP regulates microtubule orientation and dendrite pruning by suppressing Par-1 kinase. Cell Rep 2022; 39:110887. [PMID: 35649352 DOI: 10.1016/j.celrep.2022.110887] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 04/04/2022] [Accepted: 05/06/2022] [Indexed: 02/06/2023] Open
Abstract
The evolutionarily conserved CLASPs (cytoplasmic linker-associated proteins) are microtubule-associated proteins that inhibit microtubule catastrophe and promote rescue. CLASPs can regulate axonal elongation and dendrite branching in growing neurons. However, their roles in microtubule orientation and neurite pruning in remodeling neurons remain unknown. Here, we identify the Drosophila CLASP homolog Orbit/MAST, which is required for dendrite pruning in ddaC sensory neurons during metamorphosis. Orbit is important for maintenance of the minus-end-out microtubule orientation in ddaC dendrites. Our structural analysis reveals that the microtubule lattice-binding TOG2 domain is required for Orbit to regulate dendritic microtubule orientation and dendrite pruning. In a genetic modifier screen, we further identify the conserved Par-1 kinase as a suppressor of Orbit in dendritic microtubule orientation. Moreover, elevated Par-1 function impairs dendritic microtubule orientation and dendrite pruning, phenocopying orbit mutants. Overall, our study demonstrates that Drosophila CLASP governs dendritic microtubule orientation and dendrite pruning at least partly via suppressing Par-1 kinase.
Collapse
Affiliation(s)
- Shufeng Bu
- Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore, Singapore; Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | - Quan Tang
- Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore, Singapore
| | - Yan Wang
- Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore, Singapore
| | - Samuel Song Yuan Lau
- Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore, Singapore
| | - Wei Lin Yong
- Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore, Singapore
| | - Fengwei Yu
- Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore, Singapore; Department of Biological Sciences, National University of Singapore, Singapore, Singapore.
| |
Collapse
|
23
|
Almeida AC, Soares-de-Oliveira J, Drpic D, Cheeseman LP, Damas J, Lewin HA, Larkin DM, Aguiar P, Pereira AJ, Maiato H. Augmin-dependent microtubule self-organization drives kinetochore fiber maturation in mammals. Cell Rep 2022; 39:110610. [PMID: 35385739 PMCID: PMC8994134 DOI: 10.1016/j.celrep.2022.110610] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 01/07/2022] [Accepted: 03/11/2022] [Indexed: 11/29/2022] Open
Abstract
Chromosome segregation in mammals relies on the maturation of a thick bundle of kinetochore-attached microtubules known as k-fiber. How k-fibers mature from initial kinetochore microtubule attachments remains a fundamental question. By combining molecular perturbations and phenotypic analyses in Indian muntjac fibroblasts containing the lowest known diploid chromosome number in mammals (2N = 6) and distinctively large kinetochores, with fixed/live-cell super-resolution coherent-hybrid stimulated emission depletion (CH-STED) nanoscopy and laser microsurgery, we demonstrate a key role for augmin in kinetochore microtubule self-organization and maturation, regardless of pioneer centrosomal microtubules. In doing so, augmin promotes kinetochore and interpolar microtubule turnover and poleward flux. Tracking of microtubule growth events within individual k-fibers reveals a wide angular dispersion, consistent with augmin-mediated branched microtubule nucleation. Augmin depletion reduces the frequency of kinetochore microtubule growth events and hampers efficient repair after acute k-fiber injury by laser microsurgery. Together, these findings underscore the contribution of augmin-mediated microtubule amplification for k-fiber self-organization and maturation in mammals.
Collapse
Affiliation(s)
- Ana C Almeida
- Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal
| | - Joana Soares-de-Oliveira
- Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal
| | - Danica Drpic
- Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal
| | - Liam P Cheeseman
- Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal
| | - Joana Damas
- Department of Comparative Biomedical Sciences, Royal Veterinary College, University of London, London NW1 0TU, UK; Department of Evolution and Ecology, University of California, Davis, CA 95616, USA
| | - Harris A Lewin
- Department of Evolution and Ecology, University of California, Davis, CA 95616, USA
| | - Denis M Larkin
- Department of Comparative Biomedical Sciences, Royal Veterinary College, University of London, London NW1 0TU, UK
| | - Paulo Aguiar
- Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Instituto Nacional de Engenharia Biomédica (INEB), Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal
| | - António J Pereira
- Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal
| | - Helder Maiato
- Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Cell Division Group, Department of Biomedicine, Faculdade de Medicina, Universidade do Porto, Alameda Professor Hernâni Monteiro, 4200-319 Porto, Portugal.
| |
Collapse
|
24
|
Cen R, Wang L, He Y, Yue C, Tan Y, Li L, Lei X. Dermal Fibroblast Migration and Proliferation Upon Wounding or Lipopolysaccharide Exposure is Mediated by Stathmin. Front Pharmacol 2022; 12:781282. [PMID: 35153746 PMCID: PMC8831846 DOI: 10.3389/fphar.2021.781282] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 12/28/2021] [Indexed: 11/13/2022] Open
Abstract
The dermal fibroblast is a crucial executor involved in wound healing, and lipopolysaccharide is a key factor in initiating the migration and proliferation of the dermal fibroblasts, followed by wound healing. However, the underlying molecular mechanism is still unknown. In this study, we demonstrated that stathmin increased concomitantly with p38/MAPK pathway activation by lipopolysaccharide stimulation of the human dermal fibroblast (HDF), which induced microtubule (MT) depolymerization followed by increased HDF migration and proliferation. In contrast, the application of taxol, the small interfering RNA transfection of stathmin, or the application of the p38/MAPK inhibitor SB203580 suppressed MT depolymerization and HDF migration and proliferation. Additionally, the overexpression of a MKK6(Glu) mutant, which constitutively activated p38/MAPK, resulted in MT depolymerization and, subsequently, promoted HDF migration and proliferation. Our data reveal a crucial role of stathmin in HDF migration and proliferation. These findings will provide new targets and strategies for clinical interventions in wound healing.
Collapse
Affiliation(s)
| | | | | | | | | | - Lingfei Li
- *Correspondence: Lingfei Li, ; Xia Lei, .
| | - Xia Lei
- *Correspondence: Lingfei Li, ; Xia Lei, .
| |
Collapse
|
25
|
Wu YFO, Bryant AT, Nelson NT, Madey AG, Fernandes GF, Goodson HV. Overexpression of the microtubule-binding protein CLIP-170 induces a +TIP network superstructure consistent with a biomolecular condensate. PLoS One 2021; 16:e0260401. [PMID: 34890409 PMCID: PMC8664194 DOI: 10.1371/journal.pone.0260401] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2021] [Accepted: 11/09/2021] [Indexed: 12/02/2022] Open
Abstract
Proper regulation of microtubule (MT) dynamics is critical for cellular processes including cell division and intracellular transport. Plus-end tracking proteins (+TIPs) dynamically track growing MTs and play a key role in MT regulation. +TIPs participate in a complex web of intra- and inter- molecular interactions known as the +TIP network. Hypotheses addressing the purpose of +TIP:+TIP interactions include relieving +TIP autoinhibition and localizing MT regulators to growing MT ends. In addition, we have proposed that the web of +TIP:+TIP interactions has a physical purpose: creating a dynamic scaffold that constrains the structural fluctuations of the fragile MT tip and thus acts as a polymerization chaperone. Here we examine the possibility that this proposed scaffold is a biomolecular condensate (i.e., liquid droplet). Many animal +TIP network proteins are multivalent and have intrinsically disordered regions, features commonly found in biomolecular condensates. Moreover, previous studies have shown that overexpression of the +TIP CLIP-170 induces large “patch” structures containing CLIP-170 and other +TIPs; we hypothesized that these structures might be biomolecular condensates. To test this hypothesis, we used video microscopy, immunofluorescence staining, and Fluorescence Recovery After Photobleaching (FRAP). Our data show that the CLIP-170-induced patches have hallmarks indicative of a biomolecular condensate, one that contains +TIP proteins and excludes other known condensate markers. Moreover, bioinformatic studies demonstrate that the presence of intrinsically disordered regions is conserved in key +TIPs, implying that these regions are functionally significant. Together, these results indicate that the CLIP-170 induced patches in cells are phase-separated liquid condensates and raise the possibility that the endogenous +TIP network might form a liquid droplet at MT ends or other +TIP locations.
Collapse
Affiliation(s)
- Yueh-Fu O. Wu
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, United States of America
- Integrated Biomedical Sciences Graduate Program, University of Notre Dame, Notre Dame, IN, United States of America
| | - Annamarie T. Bryant
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, United States of America
- Integrated Biomedical Sciences Graduate Program, University of Notre Dame, Notre Dame, IN, United States of America
| | - Nora T. Nelson
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, United States of America
| | - Alexander G. Madey
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, United States of America
| | - Gail F. Fernandes
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, United States of America
| | - Holly V. Goodson
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, United States of America
- Integrated Biomedical Sciences Graduate Program, University of Notre Dame, Notre Dame, IN, United States of America
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, United States of America
- * E-mail:
| |
Collapse
|
26
|
Jaunky DB, Larocque K, Husser MC, Liu JT, Forgione P, Piekny A. Characterization of a recently synthesized microtubule-targeting compound that disrupts mitotic spindle poles in human cells. Sci Rep 2021; 11:23665. [PMID: 34880347 PMCID: PMC8655040 DOI: 10.1038/s41598-021-03076-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 11/26/2021] [Indexed: 11/09/2022] Open
Abstract
We reveal the effects of a new microtubule-destabilizing compound in human cells. C75 has a core thienoisoquinoline scaffold with several functional groups amenable to modification. Previously we found that sub micromolar concentrations of C75 caused cytotoxicity. We also found that C75 inhibited microtubule polymerization and competed with colchicine for tubulin-binding in vitro. However, here we found that the two compounds synergized suggesting differences in their mechanism of action. Indeed, live imaging revealed that C75 causes different spindle phenotypes compared to colchicine. Spindles remained bipolar and collapsed after colchicine treatment, while C75 caused bipolar spindles to become multipolar. Importantly, microtubules rapidly disappeared after C75-treatment, but then grew back unevenly and from multiple poles. The C75 spindle phenotype is reminiscent of phenotypes caused by depletion of ch-TOG, a microtubule polymerase, suggesting that C75 blocks microtubule polymerization in metaphase cells. C75 also caused an increase in the number of spindle poles in paclitaxel-treated cells, and combining low amounts of C75 and paclitaxel caused greater regression of multicellular tumour spheroids compared to each compound on their own. These findings warrant further exploration of C75’s anti-cancer potential.
Collapse
Affiliation(s)
| | - Kevin Larocque
- Department of Biology, Concordia University, Montreal, QC, Canada
| | - Mathieu C Husser
- Department of Biology, Concordia University, Montreal, QC, Canada
| | - Jiang Tian Liu
- Department of Chemistry and Biochemistry, Concordia University, Montreal, QC, Canada
| | - Pat Forgione
- Department of Chemistry and Biochemistry, Concordia University, Montreal, QC, Canada
| | - Alisa Piekny
- Department of Biology, Concordia University, Montreal, QC, Canada.
| |
Collapse
|
27
|
Sánchez-Huertas C, Herrera E. With the Permission of Microtubules: An Updated Overview on Microtubule Function During Axon Pathfinding. Front Mol Neurosci 2021; 14:759404. [PMID: 34924953 PMCID: PMC8675249 DOI: 10.3389/fnmol.2021.759404] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Accepted: 11/01/2021] [Indexed: 01/27/2023] Open
Abstract
During the establishment of neural circuitry axons often need to cover long distances to reach remote targets. The stereotyped navigation of these axons defines the connectivity between brain regions and cellular subtypes. This chemotrophic guidance process mostly relies on the spatio-temporal expression patterns of extracellular proteins and the selective expression of their receptors in projection neurons. Axon guidance is stimulated by guidance proteins and implemented by neuronal traction forces at the growth cones, which engage local cytoskeleton regulators and cell adhesion proteins. Different layers of guidance signaling regulation, such as the cleavage and processing of receptors, the expression of co-receptors and a wide variety of intracellular cascades downstream of receptors activation, have been progressively unveiled. Also, in the last decades, the regulation of microtubule (MT) assembly, stability and interactions with the submembranous actin network in the growth cone have emerged as crucial effector mechanisms in axon pathfinding. In this review, we will delve into the intracellular signaling cascades downstream of guidance receptors that converge on the MT cytoskeleton of the growing axon. In particular, we will focus on the microtubule-associated proteins (MAPs) network responsible of MT dynamics in the axon and growth cone. Complementarily, we will discuss new evidences that connect defects in MT scaffold proteins, MAPs or MT-based motors and axon misrouting during brain development.
Collapse
Affiliation(s)
- Carlos Sánchez-Huertas
- Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas-Universidad Miguel Hernández (CSIC-UMH), Alicante, Spain
| | | |
Collapse
|
28
|
Perlaza K, Mirvis M, Ishikawa H, Marshall W. The short flagella 1 (SHF1) gene in Chlamydomonas encodes a Crescerin TOG-domain protein required for late stages of flagellar growth. Mol Biol Cell 2021; 33:ar12. [PMID: 34818077 PMCID: PMC9236146 DOI: 10.1091/mbc.e21-09-0472] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Length control of flagella represents a simple and tractable system to investigate the dynamics of organelle size. Models for flagellar length control in the model organism, Chlamydomonas reinhardtii have focused on the length-dependence of the intraflagellar transport (IFT) system which manages the delivery and removal of axonemal subunits at the tip of the flagella. One of these cargoes, tubulin, is the major axonemal subunit, and its frequency of arrival at the tip plays a central role in size control models. However, the mechanisms determining tubulin dynamics at the tip are still poorly understood. We discovered a loss-of-function mutation that leads to shortened flagella, and found that this was an allele of a previously described gene, SHF1, whose molecular identity had not previously been determined. We found that SHF1 encodes a Chlamydomonas ortholog of Crescerin, previously identified as a cilia-specific TOG-domain array protein that can bind tubulin via its TOG domains and increase tubulin polymerization rates. In this mutant, flagellar regeneration occurs with the same initial kinetics as wild-type cells, but plateaus at a shorter length. Using a computational model in which the flagellar microtubules are represented by a differential equation for flagellar length combined with a stochastic model for cytoplasmic microtubule dynamics, we found that our experimental results are best described by a model in which Crescerin/SHF1 binds tubulin dimers in the cytoplasm and transports them into the flagellum. We suggest that this TOG-domain protein is necessary to efficiently and preemptively increase intra-flagella tubulin levels to offset decreasing IFT cargo at the tip as flagellar assembly progresses.
Collapse
Affiliation(s)
- Karina Perlaza
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94143
| | - Mary Mirvis
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94143
| | - Hiroaki Ishikawa
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94143
| | - Wallace Marshall
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94143
| |
Collapse
|
29
|
Regulation of microtubule dynamics, mechanics and function through the growing tip. Nat Rev Mol Cell Biol 2021; 22:777-795. [PMID: 34408299 DOI: 10.1038/s41580-021-00399-x] [Citation(s) in RCA: 85] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/05/2021] [Indexed: 02/07/2023]
Abstract
Microtubule dynamics and their control are essential for the normal function and division of all eukaryotic cells. This plethora of functions is, in large part, supported by dynamic microtubule tips, which can bind to various intracellular targets, generate mechanical forces and couple with actin microfilaments. Here, we review progress in the understanding of microtubule assembly and dynamics, focusing on new information about the structure of microtubule tips. First, we discuss evidence for the widely accepted GTP cap model of microtubule dynamics. Next, we address microtubule dynamic instability in the context of structural information about assembly intermediates at microtubule tips. Three currently discussed models of microtubule assembly and dynamics are reviewed. These are considered in the context of established facts and recent data, which suggest that some long-held views must be re-evaluated. Finally, we review structural observations about the tips of microtubules in cells and describe their implications for understanding the mechanisms of microtubule regulation by associated proteins, by mechanical forces and by microtubule-targeting drugs, prominently including cancer chemotherapeutics.
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
|
Hahn I, Voelzmann A, Parkin J, Fülle JB, Slater PG, Lowery LA, Sanchez-Soriano N, Prokop A. Tau, XMAP215/Msps and Eb1 co-operate interdependently to regulate microtubule polymerisation and bundle formation in axons. PLoS Genet 2021; 17:e1009647. [PMID: 34228717 PMCID: PMC8284659 DOI: 10.1371/journal.pgen.1009647] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 07/16/2021] [Accepted: 06/07/2021] [Indexed: 11/18/2022] Open
Abstract
The formation and maintenance of microtubules requires their polymerisation, but little is known about how this polymerisation is regulated in cells. Focussing on the essential microtubule bundles in axons of Drosophila and Xenopus neurons, we show that the plus-end scaffold Eb1, the polymerase XMAP215/Msps and the lattice-binder Tau co-operate interdependently to promote microtubule polymerisation and bundle organisation during axon development and maintenance. Eb1 and XMAP215/Msps promote each other's localisation at polymerising microtubule plus-ends. Tau outcompetes Eb1-binding along microtubule lattices, thus preventing depletion of Eb1 tip pools. The three factors genetically interact and show shared mutant phenotypes: reductions in axon growth, comet sizes, comet numbers and comet velocities, as well as prominent deterioration of parallel microtubule bundles into disorganised curled conformations. This microtubule curling is caused by Eb1 plus-end depletion which impairs spectraplakin-mediated guidance of extending microtubules into parallel bundles. Our demonstration that Eb1, XMAP215/Msps and Tau co-operate during the regulation of microtubule polymerisation and bundle organisation, offers new conceptual explanations for developmental and degenerative axon pathologies.
Collapse
Affiliation(s)
- Ines Hahn
- The University of Manchester, Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, School of Biological Sciences, Manchester, United Kingdom
| | - Andre Voelzmann
- The University of Manchester, Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, School of Biological Sciences, Manchester, United Kingdom
| | - Jill Parkin
- The University of Manchester, Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, School of Biological Sciences, Manchester, United Kingdom
| | - Judith B. Fülle
- The University of Manchester, Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, School of Biological Sciences, Manchester, United Kingdom
| | - Paula G. Slater
- Department of Biology, Boston College, Chestnut Hill, Massachusetts, United States of America
| | - Laura Anne Lowery
- Department of Medicine, Boston University Medical Center, Boston, Massachusetts, United States of America
| | - Natalia Sanchez-Soriano
- Department of Molecular Physiology & Cell Signalling, Institute of Systems, Molecular & Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Andreas Prokop
- The University of Manchester, Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, School of Biological Sciences, Manchester, United Kingdom
| |
Collapse
|
32
|
Barisic M, Rajendraprasad G, Steblyanko Y. The metaphase spindle at steady state - Mechanism and functions of microtubule poleward flux. Semin Cell Dev Biol 2021; 117:99-117. [PMID: 34053864 DOI: 10.1016/j.semcdb.2021.05.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 05/13/2021] [Accepted: 05/13/2021] [Indexed: 11/24/2022]
Abstract
The mitotic spindle is a bipolar cellular structure, built from tubulin polymers, called microtubules, and interacting proteins. This macromolecular machine orchestrates chromosome segregation, thereby ensuring accurate distribution of genetic material into the two daughter cells during cell division. Powered by GTP hydrolysis upon tubulin polymerization, the microtubule ends exhibit a metastable behavior known as the dynamic instability, during which they stochastically switch between the growth and shrinkage phases. In the context of the mitotic spindle, dynamic instability is furthermore regulated by microtubule-associated proteins and motor proteins, which enables the spindle to undergo profound changes during mitosis. This highly dynamic behavior is essential for chromosome capture and congression in prometaphase, as well as for chromosome alignment to the spindle equator in metaphase and their segregation in anaphase. In this review we focus on the mechanisms underlying microtubule dynamics and sliding and their importance for the maintenance of shape, structure and dynamics of the metaphase spindle. We discuss how these spindle properties are related to the phenomenon of microtubule poleward flux, highlighting its highly cooperative molecular basis and role in keeping the metaphase spindle at a steady state.
Collapse
Affiliation(s)
- Marin Barisic
- Cell Division and Cytoskeleton, Danish Cancer Society Research Center (DCRC), Strandboulevarden 49, 2100 Copenhagen, Denmark; Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark.
| | - Girish Rajendraprasad
- Cell Division and Cytoskeleton, Danish Cancer Society Research Center (DCRC), Strandboulevarden 49, 2100 Copenhagen, Denmark
| | - Yulia Steblyanko
- Cell Division and Cytoskeleton, Danish Cancer Society Research Center (DCRC), Strandboulevarden 49, 2100 Copenhagen, Denmark
| |
Collapse
|
33
|
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
|
34
|
Abstract
Veronica Farmer and Marija Zanic introduce TOG-domain proteins, which regulate microtubule dynamics in a range of cellular contexts.
Collapse
Affiliation(s)
- Veronica J Farmer
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37240, USA
| | - Marija Zanic
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37240, USA; Department of Biomolecular and Chemical Engineering, Department of Biochemistry, Vanderbilt University, Nashville, TN 37240, USA.
| |
Collapse
|
35
|
Spindle scaling mechanisms. Essays Biochem 2021; 64:383-396. [PMID: 32501481 DOI: 10.1042/ebc20190064] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 05/11/2020] [Accepted: 05/12/2020] [Indexed: 02/02/2023]
Abstract
The mitotic spindle robustly scales with cell size in a plethora of different organisms. During development and throughout evolution, the spindle adjusts to cell size in metazoans and yeast in order to ensure faithful chromosome separation. Spindle adjustment to cell size occurs by the scaling of spindle length, spindle shape and the velocity of spindle assembly and elongation. Different mechanisms, depending on spindle structure and organism, account for these scaling relationships. The limited availability of critical spindle components, protein gradients, sequestration of spindle components, or post-translational modification and differential expression levels have been implicated in the regulation of spindle length and the spindle assembly/elongation velocity in a cell size-dependent manner. In this review, we will discuss the phenomenon and mechanisms of spindle length, spindle shape and spindle elongation velocity scaling with cell size.
Collapse
|
36
|
Ohi R, Strothman C, Zanic M. Impact of the 'tubulin economy' on the formation and function of the microtubule cytoskeleton. Curr Opin Cell Biol 2021; 68:81-89. [PMID: 33160109 PMCID: PMC7925340 DOI: 10.1016/j.ceb.2020.09.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 09/25/2020] [Accepted: 09/28/2020] [Indexed: 12/19/2022]
Abstract
The microtubule cytoskeleton is assembled from a finite pool of α,β-tubulin, the size of which is controlled by an autoregulation mechanism. Cells also tightly regulate the architecture and dynamic behavior of microtubule arrays. Here, we discuss progress in our understanding of how tubulin autoregulation is achieved and highlight work showing that tubulin, in its unassembled state, is relevant for regulating the formation and organization of microtubules. Emerging evidence suggests that tubulin regulates microtubule-associated proteins and kinesin motors that are critical for microtubule nucleation, dynamics, and function. These relationships create feedback loops that connect the tubulin assembly cycle to the organization and dynamics of microtubule networks. We term this concept the 'tubulin economy', which emphasizes the idea that tubulin is a resource that can be deployed for the immediate purpose of creating polymers, or alternatively as a signaling molecule that has more far-reaching consequences for the organization of microtubule arrays.
Collapse
Affiliation(s)
- Ryoma Ohi
- Department of Cell and Developmental Biology, University of Michigan, USA.
| | - Claire Strothman
- Department of Cell and Developmental Biology, Vanderbilt University, USA
| | - Marija Zanic
- Department of Cell and Developmental Biology, Vanderbilt University, USA; Department of Biomolecular and Chemical Engineering, Department of Biochemistry, Vanderbilt University, USA.
| |
Collapse
|
37
|
Reusch S, Biswas A, Hirst WG, Reber S. Affinity Purification of Label-free Tubulins from Xenopus Egg Extracts. STAR Protoc 2020; 1:100151. [PMID: 33377045 PMCID: PMC7757314 DOI: 10.1016/j.xpro.2020.100151] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Cytoplasmic extracts from unfertilized Xenopus eggs have made important contributions to our understanding of microtubule dynamics, spindle assembly, and scaling. Until recently, these in vitro studies relied on the use of heterologous tubulin. This protocol allows for the purification of physiologically relevant Xenopus tubulins in milligram yield, which are a complex mixture of isoforms with various post-translational modifications. The protocol is applicable to any cell or tissue of interest. For complete details on the use and execution of this protocol, please refer to Hirst et al. (2020).
Collapse
Affiliation(s)
- Sebastian Reusch
- IRI Life Sciences, Humboldt-Universität zu Berlin, 10115 Berlin, Germany
- Marine Biological Laboratory, Woods Hole, MA 02543, USA
| | - Abin Biswas
- IRI Life Sciences, Humboldt-Universität zu Berlin, 10115 Berlin, Germany
- Max-Planck-Institute for the Physics of Light, 91058 Erlangen, Germany
- Marine Biological Laboratory, Woods Hole, MA 02543, USA
| | - William Graham Hirst
- IRI Life Sciences, Humboldt-Universität zu Berlin, 10115 Berlin, Germany
- Research School of Biology, The Australian National University, Canberra, ACT 2600, Australia
- Marine Biological Laboratory, Woods Hole, MA 02543, USA
| | - Simone Reber
- IRI Life Sciences, Humboldt-Universität zu Berlin, 10115 Berlin, Germany
- University of Applied Sciences Berlin, 13353 Berlin, Germany
- Marine Biological Laboratory, Woods Hole, MA 02543, USA
| |
Collapse
|
38
|
Zhu Y, Zhang Y, Liu N, Ren W, Hou Y, Duan Y, Song X, Zhou M. The Dis1/Stu2/XMAP215 Family Gene FgStu2 Is Involved in Vegetative Growth, Morphology, Sexual and Asexual Reproduction, Pathogenicity and DON Production of Fusarium graminearum. Front Microbiol 2020; 11:545015. [PMID: 33329417 PMCID: PMC7714731 DOI: 10.3389/fmicb.2020.545015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Accepted: 10/29/2020] [Indexed: 11/29/2022] Open
Abstract
The conserved Dis1/Stu2/XMAP215 microtubule association proteins (MAPs) family plays an important role in microtubule dynamics, nucleation, and kinetochore-microtubule attachments. However, function of Dis1/Stu2/XMAP215 homolog in plant pathogenic fungi has not been determined. Here, we identified and investigated the Dis1/Stu2/XMAP215 homolog (FGSG_10528) in Fusarium graminearum (FgStu2p). Co-localization experiment and co-immunoprecipitation (Co-IP) assay demonstrated that FgStu2p is a microtubule associated protein. Besides, FgStu2 could also interact with Fgγ-tubulin and presumed FgNdc80, which suggested that the FgStu2 gene might associate with microtubule nucleation and kinetochore-microtubule attachments like Dis1/Stu2/XMAP215 homologs in other species. Moreover, the FgStu2 promoter replacement mutants (FgStu2-Si mutants) produced twisted hyphae and decreased growth rate. Microscope examination further showed that the microtubule polymerization was reduced in FgStu2-Si mutants, which could account for the aberrant morphology. Although the microtubule polymerization was affected in FgStu2-Si mutants, the FgStu2-Si mutants didn't show highly increased sensitivity to anti-microtubule fungicide carbendazim (methyl benzimidazol-2-ylcarbamate [MBC]). In addition, the FgStu2-Si mutants exhibited curved conidia, decreased number of conidial production, blocked ability of perithecia production, decreased pathogenicity and deoxynivalenol (DON) production. Taken together, these results indicate that the FgStu2 gene plays a crucial role in vegetative growth, morphology, sexual reproduction, asexual reproduction, virulence and deoxynivalenol (DON) production of F. graminearum, which brings new insights into the functions of Dis1/Stu2/XMAP215 homolog in plant pathogenic fungi.
Collapse
Affiliation(s)
- Yuanye Zhu
- College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Yuanshuai Zhang
- College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Na Liu
- College of Plant Health and Medicine, Qingdao Agricultural University, Qingdao, China
| | - Weichao Ren
- College of Plant Health and Medicine, Qingdao Agricultural University, Qingdao, China
| | - Yiping Hou
- College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Yabing Duan
- College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Xiushi Song
- College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Mingguo Zhou
- College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| |
Collapse
|
39
|
Yamazoe T, Nagai T, Umeda S, Sugaya Y, Mizuno K. Roles of TOG and jelly-roll domains of centrosomal protein CEP104 in its functions in cilium elongation and Hedgehog signaling. J Biol Chem 2020; 295:14723-14736. [PMID: 32820051 DOI: 10.1074/jbc.ra120.013334] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 08/11/2020] [Indexed: 12/26/2022] Open
Abstract
Primary cilia are generated through the extension of the microtubule-based axoneme. Centrosomal protein 104 (CEP104) localizes to the tip of the elongating axoneme, and CEP104 mutations are linked to a ciliopathy, Joubert syndrome. Thus, CEP104 has been implicated in ciliogenesis. However, the mechanism by which CEP104 regulates ciliogenesis remains elusive. We report here that CEP104 is critical for cilium elongation but not for initiating ciliogenesis. We also demonstrated that the tumor-overexpressed gene (TOG) domain of CEP104 exhibits microtubule-polymerizing activity and that this activity is essential for the cilium-elongating activity of CEP104. Knockdown/rescue experiments showed that the N-terminal jelly-roll (JR) fold partially contributes to cilium-elongating activity of CEP104, but neither the zinc-finger region nor the SXIP motif is required for this activity. CEP104 binds to a centriole-capping protein, CP110, through the zinc-finger region and to a microtubule plus-end-binding protein, EB1, through the SXIP motif, indicating that the binding of CP110 and EB1 is dispensable for the cilium-elongating activity of CEP104. Moreover, CEP104 depletion does not affect CP110 removal from the mother centriole, which suggests that CEP104 functions after the removal of CP110. Last, we also showed that CEP104 is required for the ciliary entry of Smoothened and export of GPR161 upon Hedgehog signal activation and that the TOG domain plays a critical role in this activity. Our results define the roles of the individual domains of CEP104 in its functions in cilium elongation and Hedgehog signaling and should enhance our understanding of the mechanism underlying CEP104 mutation-associated ciliopathies.
Collapse
Affiliation(s)
- Takashi Yamazoe
- Department of Molecular and Chemical Life Sciences, Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi, Japan
| | - Tomoaki Nagai
- Department of Molecular and Chemical Life Sciences, Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi, Japan; Department of Biochemistry, Fukushima Medical University School of Medicine, Fukushima, Japan.
| | - Shinya Umeda
- Department of Molecular and Chemical Life Sciences, Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi, Japan
| | - Yuko Sugaya
- Department of Molecular and Chemical Life Sciences, Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi, Japan
| | - Kensaku Mizuno
- Department of Molecular and Chemical Life Sciences, Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi, Japan; Institute of Liberal Arts and Sciences, Tohoku University, Kawauchi, Sendai, Miyagi, Japan.
| |
Collapse
|
40
|
Abstract
Enzymatic reactions and noncovalent (i.e., supramolecular) interactions are two fundamental nongenetic attributes of life. Enzymatic noncovalent synthesis (ENS) refers to a process where enzymatic reactions control intermolecular noncovalent interactions for spatial organization of higher-order molecular assemblies that exhibit emergent properties and functions. Like enzymatic covalent synthesis (ECS), in which an enzyme catalyzes the formation of covalent bonds to generate individual molecules, ENS is a unifying theme for understanding the functions, morphologies, and locations of molecular ensembles in cellular environments. This review intends to provide a summary of the works of ENS within the past decade and emphasize ENS for functions. After comparing ECS and ENS, we describe a few representative examples where nature uses ENS, as a rule of life, to create the ensembles of biomacromolecules for emergent properties/functions in a myriad of cellular processes. Then, we focus on ENS of man-made (synthetic) molecules in cell-free conditions, classified by the types of enzymes. After that, we introduce the exploration of ENS of man-made molecules in the context of cells by discussing intercellular, peri/intracellular, and subcellular ENS for cell morphogenesis, molecular imaging, cancer therapy, and other applications. Finally, we provide a perspective on the promises of ENS for developing molecular assemblies/processes for functions. This review aims to be an updated introduction for researchers who are interested in exploring noncovalent synthesis for developing molecular science and technologies to address societal needs.
Collapse
Affiliation(s)
- Hongjian He
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, Massachusetts 02454, United States
| | - Weiyi Tan
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, Massachusetts 02454, United States
| | - Jiaqi Guo
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, Massachusetts 02454, United States
| | - Meihui Yi
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, Massachusetts 02454, United States
| | - Adrianna N Shy
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, Massachusetts 02454, United States
| | - Bing Xu
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, Massachusetts 02454, United States
| |
Collapse
|
41
|
Rondelet A, Lin YC, Singh D, Porfetye AT, Thakur HC, Hecker A, Brinkert P, Schmidt N, Bendre S, Müller F, Mazul L, Widlund PO, Bange T, Hiller M, Vetter IR, Bird AW. Clathrin's adaptor interaction sites are repurposed to stabilize microtubules during mitosis. J Cell Biol 2020; 219:133599. [PMID: 31932847 PMCID: PMC7041688 DOI: 10.1083/jcb.201907083] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 10/31/2019] [Accepted: 11/24/2019] [Indexed: 11/22/2022] Open
Abstract
Clathrin ensures mitotic spindle stability and efficient chromosome alignment, independently of its vesicle trafficking function. Although clathrin localizes to the mitotic spindle and kinetochore fiber microtubule bundles, the mechanisms by which clathrin stabilizes microtubules are unclear. We show that clathrin adaptor interaction sites on clathrin heavy chain (CHC) are repurposed during mitosis to directly recruit the microtubule-stabilizing protein GTSE1 to the spindle. Structural analyses reveal that these sites interact directly with clathrin-box motifs on GTSE1. Disruption of this interaction releases GTSE1 from spindles, causing defects in chromosome alignment. Surprisingly, this disruption destabilizes astral microtubules, but not kinetochore-microtubule attachments, and chromosome alignment defects are due to a failure of chromosome congression independent of kinetochore-microtubule attachment stability. GTSE1 recruited to the spindle by clathrin stabilizes microtubules by inhibiting the microtubule depolymerase MCAK. This work uncovers a novel role of clathrin adaptor-type interactions to stabilize nonkinetochore fiber microtubules to support chromosome congression, defining for the first time a repurposing of this endocytic interaction mechanism during mitosis.
Collapse
Affiliation(s)
- Arnaud Rondelet
- Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Yu-Chih Lin
- Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Divya Singh
- Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | | | - Harish C Thakur
- Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Andreas Hecker
- Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Pia Brinkert
- Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Nadine Schmidt
- Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Shweta Bendre
- Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | | | - Lisa Mazul
- Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Per O Widlund
- Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Tanja Bange
- Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Michael Hiller
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany.,Max Planck Institute for the Physics of Complex Systems, Dresden, Germany.,Center for Systems Biology, Dresden, Germany
| | - Ingrid R Vetter
- Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | | |
Collapse
|
42
|
A CEP104-CSPP1 Complex Is Required for Formation of Primary Cilia Competent in Hedgehog Signaling. Cell Rep 2020; 28:1907-1922.e6. [PMID: 31412255 PMCID: PMC6702141 DOI: 10.1016/j.celrep.2019.07.025] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 05/21/2019] [Accepted: 07/10/2019] [Indexed: 12/25/2022] Open
Abstract
CEP104 is an evolutionarily conserved centrosomal and ciliary tip protein. CEP104 loss-of-function mutations are reported in patients with Joubert syndrome, but their function in the etiology of ciliopathies is poorly understood. Here, we show that cep104 silencing in zebrafish causes cilia-related manifestations: shortened cilia in Kupffer’s vesicle, heart laterality, and cranial nerve development defects. We show that another Joubert syndrome-associated cilia tip protein, CSPP1, interacts with CEP104 at microtubules for the regulation of axoneme length. We demonstrate in human telomerase reverse transcriptase-immortalized retinal pigmented epithelium (hTERT-RPE1) cells that ciliary translocation of Smoothened in response to Hedgehog pathway stimulation is both CEP104 and CSPP1 dependent. However, CEP104 is not required for the ciliary recruitment of CSPP1, indicating that an intra-ciliary CEP104-CSPP1 complex controls axoneme length and Hedgehog signaling competence. Our in vivo and in vitro analyses of CEP104 define its interaction with CSPP1 as a requirement for the formation of Hedgehog signaling-competent cilia, defects that underlie Joubert syndrome. cep104-depleted zebrafish display shortened KV cilia and defective brain development CEP104 interacts with CSPP1 at the tip of the primary cilium to regulate cilia length CEP104 or CSPP1 loss in human cells leads to defective Hedgehog signaling Impaired signaling is linked to reduction of ciliary SMO but not ARL13B or INPP5E
Collapse
|
43
|
Benzi G, Piatti S. Killing two birds with one stone: how budding yeast Mps1 controls chromosome segregation and spindle assembly checkpoint through phosphorylation of a single kinetochore protein. Curr Genet 2020; 66:1037-1044. [PMID: 32632756 DOI: 10.1007/s00294-020-01091-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 06/23/2020] [Accepted: 06/25/2020] [Indexed: 12/11/2022]
Abstract
During mitosis, the identical sister chromatids of each chromosome must attach through their kinetochores to microtubules emanating from opposite spindle poles. This process, referred to as chromosome biorientation, is essential for equal partitioning of the genetic information to the two daughter cells. Defects in chromosome biorientation can give rise to aneuploidy, a hallmark of cancer and genetic diseases. A conserved surveillance mechanism called spindle assembly checkpoint (SAC) prevents the onset of anaphase until biorientation is attained. Key to chromosome biorientation is an error correction mechanism that allows kinetochores to establish proper bipolar attachments by disengaging faulty kinetochore-microtubule connections. Error correction relies on the Aurora B and Mps1 kinases that also promote SAC signaling, raising the possibility that they are part of a single sensory device responding to improper attachments and concomitantly controlling both their disengagement and a temporary mitotic arrest. In budding yeast, Aurora B and Mps1 promote error correction independently from one another, but while the substrates of Aurora B in this process are at least partially known, the mechanism underlying the involvement of Mps1 in the error correction pathway is unknown. Through the characterization of a novel mps1 mutant and an unbiased genetic screen for extragenic suppressors, we recently gained evidence that a common mechanism based on Mps1-dependent phosphorylation of the Knl1/Spc105 kinetochore scaffold and subsequent recruitment of the Bub1 kinase is critical for the function of Mps1 in chromosome biorientation as well as for SAC activation (Benzi et al. EMBO Rep, 2020).
Collapse
Affiliation(s)
- Giorgia Benzi
- CRBM, University of Montpellier, CNRS, 1919 Route de Mende, 34293, Montpellier, France
| | - Simonetta Piatti
- CRBM, University of Montpellier, CNRS, 1919 Route de Mende, 34293, Montpellier, France.
| |
Collapse
|
44
|
How Essential Kinesin-5 Becomes Non-Essential in Fission Yeast: Force Balance and Microtubule Dynamics Matter. Cells 2020; 9:cells9051154. [PMID: 32392819 PMCID: PMC7290485 DOI: 10.3390/cells9051154] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 05/01/2020] [Accepted: 05/04/2020] [Indexed: 12/13/2022] Open
Abstract
The bipolar mitotic spindle drives accurate chromosome segregation by capturing the kinetochore and pulling each set of sister chromatids to the opposite poles. In this review, we describe recent findings on the multiple pathways leading to bipolar spindle formation in fission yeast and discuss these results from a broader perspective. The roles of three mitotic kinesins (Kinesin-5, Kinesin-6 and Kinesin-14) in spindle assembly are depicted, and how a group of microtubule-associated proteins, sister chromatid cohesion and the kinetochore collaborate with these motors is shown. We have paid special attention to the molecular pathways that render otherwise essential Kinesin-5 to become non-essential: how cells build bipolar mitotic spindles without the need for Kinesin-5 and where the alternate forces come from are considered. We highlight the force balance for bipolar spindle assembly and explain how outward and inward forces are generated by various ways, in which the proper fine-tuning of microtubule dynamics plays a crucial role. Overall, these new pathways have illuminated the remarkable plasticity and adaptability of spindle mechanics. Kinesin molecules are regarded as prospective targets for cancer chemotherapy and many specific inhibitors have been developed. However, several hurdles have arisen against their clinical implementation. This review provides insight into possible strategies to overcome these challenges.
Collapse
|
45
|
Aher A, Rai D, Schaedel L, Gaillard J, John K, Liu Q, Altelaar M, Blanchoin L, Thery M, Akhmanova A. CLASP Mediates Microtubule Repair by Restricting Lattice Damage and Regulating Tubulin Incorporation. Curr Biol 2020; 30:2175-2183.e6. [PMID: 32359430 PMCID: PMC7280784 DOI: 10.1016/j.cub.2020.03.070] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 03/05/2020] [Accepted: 03/27/2020] [Indexed: 11/18/2022]
Abstract
Microtubules play a key role in cell division, motility, and intracellular trafficking. Microtubule lattices are generally regarded as stable structures that undergo turnover through dynamic instability of their ends [1]. However, recent evidence suggests that microtubules also exchange tubulin dimers at the sites of lattice defects, which can be induced by mechanical stress, severing enzymes, or occur spontaneously during polymerization [2, 3, 4, 5, 6]. Tubulin incorporation can restore microtubule integrity; moreover, “islands” of freshly incorporated GTP-tubulin can inhibit microtubule disassembly and promote rescues [3, 4, 6, 7, 8]. Microtubule repair occurs in vitro in the presence of tubulin alone [2, 3, 4, 5, 6, 9]. However, in cells, it is likely to be regulated by specific factors, the nature of which is currently unknown. CLASPs are interesting candidates for microtubule repair because they induce microtubule nucleation, stimulate rescue, and suppress catastrophes by stabilizing incomplete growing plus ends with lagging protofilaments and promoting their conversion into complete ones [10, 11, 12, 13, 14, 15, 16, 17]. Here, we used in vitro reconstitution assays combined with laser microsurgery and microfluidics to show that CLASP2α indeed stimulates microtubule lattice repair. CLASP2α promoted tubulin incorporation into damaged lattice sites, thereby restoring microtubule integrity. Furthermore, it induced the formation of complete tubes from partial protofilament assemblies and inhibited microtubule softening caused by hydrodynamic-flow-induced bending. The catastrophe-suppressing domain of CLASP2α, TOG2, combined with a microtubule-tethering region, was sufficient to stimulate microtubule repair, suggesting that catastrophe suppression and lattice repair are mechanistically similar. Our results suggest that the cellular machinery controlling microtubule nucleation and growth can also help to maintain microtubule integrity. CLASP stabilizes damaged microtubule lattices CLASP converts partial protofilament assemblies into complete tubes CLASP promotes complete repair of microtubule lattice defects CLASP inhibits softening of microtubules bent by hydrodynamic flow
Collapse
Affiliation(s)
- Amol Aher
- Cell Biology, Neurobiology and Biophysics, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH Utrecht, the Netherlands
| | - Dipti Rai
- Cell Biology, Neurobiology and Biophysics, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH Utrecht, the Netherlands
| | - Laura Schaedel
- University of Grenoble-Alpes, CEA, CNRS, INRA, Interdisciplinary Research Institute of Grenoble, Laboratoire de Phyiologie Cellulaire & Végétale, CytoMorpho Lab, 38054 Grenoble, France
| | - Jeremie Gaillard
- University of Grenoble-Alpes, CEA, CNRS, INRA, Interdisciplinary Research Institute of Grenoble, Laboratoire de Phyiologie Cellulaire & Végétale, CytoMorpho Lab, 38054 Grenoble, France
| | - Karin John
- University of Grenoble-Alpes, CNRS, Laboratoire Interdisciplinaire de Physique, 38000 Grenoble, France
| | - Qingyang Liu
- Cell Biology, Neurobiology and Biophysics, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH Utrecht, the Netherlands
| | - Maarten Altelaar
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research, Utrecht Institute for Pharmaceutical Sciences and the Netherlands Proteomics Centre, Utrecht University, Padualaan 8, 3584 CH Utrecht, the Netherlands
| | - Laurent Blanchoin
- University of Grenoble-Alpes, CEA, CNRS, INRA, Interdisciplinary Research Institute of Grenoble, Laboratoire de Phyiologie Cellulaire & Végétale, CytoMorpho Lab, 38054 Grenoble, France; Université de Paris, INSERM, CEA, Institut de Recherche Saint Louis, U 976, CytoMorpho Lab, 75010 Paris, France
| | - Manuel Thery
- University of Grenoble-Alpes, CEA, CNRS, INRA, Interdisciplinary Research Institute of Grenoble, Laboratoire de Phyiologie Cellulaire & Végétale, CytoMorpho Lab, 38054 Grenoble, France; Université de Paris, INSERM, CEA, Institut de Recherche Saint Louis, U 976, CytoMorpho Lab, 75010 Paris, France
| | - Anna Akhmanova
- Cell Biology, Neurobiology and Biophysics, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH Utrecht, the Netherlands.
| |
Collapse
|
46
|
Abstract
CLIP-associating proteins (CLASPs) form an evolutionarily conserved family of regulatory factors that control microtubule dynamics and the organization of microtubule networks. The importance of CLASP activity has been appreciated for some time, but until recently our understanding of the underlying molecular mechanisms remained basic. Over the past few years, studies of, for example, migrating cells, neuronal development, and microtubule reorganization in plants, along with in vitro reconstitutions, have provided new insights into the cellular roles and molecular basis of CLASP activity. In this Cell Science at a Glance article and the accompanying poster, we will summarize some of these recent advances, emphasizing how they impact our current understanding of CLASP-mediated microtubule regulation.
Collapse
Affiliation(s)
- Elizabeth J Lawrence
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN, USA
| | - Marija Zanic
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN, USA
- Department of Chemical and Biomolecular Engineering, and Department of Biochemistry, Vanderbilt University, Nashville, TN 37232, USA
| | - Luke M Rice
- Department of Biophysics and Department of Biochemistry, UT Southwestern Medical Center, Dallas, TX 75390, USA
| |
Collapse
|
47
|
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
|
48
|
Qu Y, Hahn I, Lees M, Parkin J, Voelzmann A, Dorey K, Rathbone A, Friel CT, Allan VJ, Okenve-Ramos P, Sanchez-Soriano N, Prokop A. Efa6 protects axons and regulates their growth and branching by inhibiting microtubule polymerisation at the cortex. eLife 2019; 8:e50319. [PMID: 31718774 PMCID: PMC6884004 DOI: 10.7554/elife.50319] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 11/06/2019] [Indexed: 12/12/2022] Open
Abstract
Cortical collapse factors affect microtubule (MT) dynamics at the plasma membrane. They play important roles in neurons, as suggested by inhibition of axon growth and regeneration through the ARF activator Efa6 in C. elegans, and by neurodevelopmental disorders linked to the mammalian kinesin Kif21A. How cortical collapse factors influence axon growth is little understood. Here we studied them, focussing on the function of Drosophila Efa6 in experimentally and genetically amenable fly neurons. First, we show that Drosophila Efa6 can inhibit MTs directly without interacting molecules via an N-terminal 18 amino acid motif (MT elimination domain/MTED) that binds tubulin and inhibits microtubule growth in vitro and cells. If N-terminal MTED-containing fragments are in the cytoplasm they abolish entire microtubule networks of mouse fibroblasts and whole axons of fly neurons. Full-length Efa6 is membrane-attached, hence primarily blocks MTs in the periphery of fibroblasts, and explorative MTs that have left axonal bundles in neurons. Accordingly, loss of Efa6 causes an increase of explorative MTs: in growth cones they enhance axon growth, in axon shafts they cause excessive branching, as well as atrophy through perturbations of MT bundles. Efa6 over-expression causes the opposite phenotypes. Taken together, our work conceptually links molecular and sub-cellular functions of cortical collapse factors to axon growth regulation and reveals new roles in axon branching and in the prevention of axonal atrophy. Furthermore, the MTED delivers a promising tool that can be used to inhibit MTs in a compartmentalised fashion when fusing it to specifically localising protein domains.
Collapse
Affiliation(s)
- Yue Qu
- Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, School of Biological SciencesThe University of ManchesterManchesterUnited Kingdom
| | - Ines Hahn
- Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, School of Biological SciencesThe University of ManchesterManchesterUnited Kingdom
| | - Meredith Lees
- Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, School of Biological SciencesThe University of ManchesterManchesterUnited Kingdom
| | - Jill Parkin
- Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, School of Biological SciencesThe University of ManchesterManchesterUnited Kingdom
| | - André Voelzmann
- Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, School of Biological SciencesThe University of ManchesterManchesterUnited Kingdom
| | - Karel Dorey
- Faculty of Biology, Medicine and Health, School of Medical SciencesThe University of ManchesterManchesterUnited Kingdom
| | - Alex Rathbone
- School of Life Sciences, Faculty of Medicine and Health SciencesThe University of NottinghamNottinghamUnited Kingdom
| | - Claire T Friel
- School of Life Sciences, Faculty of Medicine and Health SciencesThe University of NottinghamNottinghamUnited Kingdom
| | - Victoria J Allan
- Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, School of Biological SciencesThe University of ManchesterManchesterUnited Kingdom
| | - Pilar Okenve-Ramos
- Department of Cellular and Molecular Physiology,Institute of Translational MedicineUniversity of LiverpoolLiverpoolUnited Kingdom
| | - Natalia Sanchez-Soriano
- Department of Cellular and Molecular Physiology,Institute of Translational MedicineUniversity of LiverpoolLiverpoolUnited Kingdom
| | - Andreas Prokop
- Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, School of Biological SciencesThe University of ManchesterManchesterUnited Kingdom
| |
Collapse
|
49
|
Two XMAP215/TOG Microtubule Polymerases, Alp14 and Dis1, Play Non-Exchangeable, Distinct Roles in Microtubule Organisation in Fission Yeast. Int J Mol Sci 2019; 20:ijms20205108. [PMID: 31618856 PMCID: PMC6834199 DOI: 10.3390/ijms20205108] [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: 10/04/2019] [Revised: 10/12/2019] [Accepted: 10/12/2019] [Indexed: 12/29/2022] Open
Abstract
Proper bipolar spindle assembly underlies accurate chromosome segregation. A cohort of microtubule-associated proteins orchestrates spindle microtubule formation in a spatiotemporally coordinated manner. Among them, the conserved XMAP215/TOG family of microtubule polymerase plays a central role in spindle assembly. In fission yeast, two XMAP215/TOG members, Alp14 and Dis1, share essential roles in cell viability; however how these two proteins functionally collaborate remains undetermined. Here we show the functional interplay and specification of Alp14 and Dis1. Creation of new mutant alleles of alp14, which display temperature sensitivity in the absence of Dis1, enabled us to conduct detailed analyses of a double mutant. We have found that simultaneous inactivation of Alp14 and Dis1 results in early mitotic arrest with very short, fragile spindles. Intriguingly, these cells often undergo spindle collapse, leading to a lethal “cut” phenotype. By implementing an artificial targeting system, we have shown that Alp14 and Dis1 are not functionally exchangeable and as such are not merely redundant paralogues. Interestingly, while Alp14 promotes microtubule nucleation, Dis1 does not. Our results uncover that the intrinsic specification, not the spatial regulation, between Alp14 and Dis1 underlies the collaborative actions of these two XMAP215/TOG members in mitotic progression, spindle integrity and genome stability.
Collapse
|
50
|
Drechsler H, Xu Y, Geyer VF, Zhang Y, Diez S. Multivalent electrostatic microtubule interactions of synthetic peptides are sufficient to mimic advanced MAP-like behavior. Mol Biol Cell 2019; 30:2953-2968. [PMID: 31599700 PMCID: PMC6857568 DOI: 10.1091/mbc.e19-05-0247] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Microtubule-associated proteins (MAPs) are a functionally highly diverse class of proteins that help to adjust the shape and function of the microtubule cytoskeleton in space and time. For this purpose, MAPs structurally support microtubules, modulate their dynamic instability, or regulate the activity of associated molecular motors. The microtubule-binding domains of MAPs are structurally divergent, but often depend on electrostatic interactions with the negatively charged surface of the microtubule. This suggests that the surface exposure of positive charges rather than a certain structural fold is sufficient for a protein to associate with microtubules. Consistently, positively charged artificial objects have been shown to associate with microtubules and to diffuse along their lattice. Natural MAPs, however, show a more sophisticated functionality beyond lattice-diffusion. Here, we asked whether basic electrostatic interactions are sufficient to also support advanced MAP functionality. To test this hypothesis, we studied simple positively charged peptide sequences for the occurrence of typical MAP-like behavior. We found that a multivalent peptide construct featuring four lysine-alanine heptarepeats (starPEG-(KA7)4)-but not its monovalent KA7-subunits-show advanced, biologically relevant MAP-like behavior: starPEG-(KA7)4 binds microtubules in the low nanomolar range, diffuses along their lattice with the ability to switch between intersecting microtubules, and tracks depolymerizing microtubule ends. Further, starPEG-(KA7)4 promotes microtubule nucleation and growth, mediates depolymerization coupled pulling at plus ends, and bundles microtubules without significantly interfering with other proteins on the microtubule lattice (as exemplified by the motor kinesin-1). Our results show that positive charges and multivalency are sufficient to mimic advanced MAP-like behavior.
Collapse
Affiliation(s)
- Hauke Drechsler
- B CUBE-Center for Molecular Bioengineering, Technische -Universität -Dresden, Dresden 01307, Germany
| | - Yong Xu
- B CUBE-Center for Molecular Bioengineering, Technische -Universität -Dresden, Dresden 01307, Germany
| | - Veikko F Geyer
- B CUBE-Center for Molecular Bioengineering, Technische -Universität -Dresden, Dresden 01307, Germany
| | - Yixin Zhang
- B CUBE-Center for Molecular Bioengineering, Technische -Universität -Dresden, Dresden 01307, Germany
| | - Stefan Diez
- B CUBE-Center for Molecular Bioengineering, Technische -Universität -Dresden, Dresden 01307, Germany.,Cluster of Excellence Physics of Life, Technische -Universität -Dresden, Dresden 01307, Germany.,Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany
| |
Collapse
|