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Jongsma MLM, Bakker N, Voortman LM, Koning RI, Bos E, Akkermans JJLL, Janssen L, Neefjes J. Systems mapping of bidirectional endosomal transport through the crowded cell. Curr Biol 2024; 34:4476-4494.e11. [PMID: 39276769 PMCID: PMC11466077 DOI: 10.1016/j.cub.2024.08.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Revised: 07/02/2024] [Accepted: 08/15/2024] [Indexed: 09/17/2024]
Abstract
Kinesin and dynein-dynactin motors move endosomes and other vesicles bidirectionally along microtubules, a process mainly studied under in vitro conditions. Here, we provide a physiological bidirectional transport model following color-coded, endogenously tagged transport-related proteins as they move through a crowded cellular environment. Late endosomes (LEs) surf bidirectionally on Protrudin-enriched endoplasmic reticulum (ER) membrane contact sites, while hopping and gliding along microtubules and bypassing cellular obstacles, such as mitochondria. During bidirectional transport, late endosomes do not switch between opposing Rab7 GTPase effectors, RILP and FYCO1, or their associated dynein and KIF5B motor proteins, respectively. In the endogenous setting, far fewer motors associate with endosomal membranes relative to effectors, implying coordination of transport with other aspects of endosome physiology through GTPase-regulated mechanisms. We find that directionality of transport is provided in part by various microtubule-associated proteins (MAPs), including MID1, EB1, and CEP169, which recruit Lis1-activated dynein motors to microtubule plus ends for transport of early and late endosomal populations. At these microtubule plus ends, activated dynein motors encounter the dynactin subunit p150glued and become competent for endosomal capture and minus-end movement in collaboration with membrane-associated Rab7-RILP. We show that endosomes surf over the ER through the crowded cell and move bidirectionally under the control of MAPs for motor activation and through motor replacement and capture by endosomal anchors.
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Affiliation(s)
- Marlieke L M Jongsma
- Department of Cell and Chemical Biology, ONCODE institute, Leiden University Medical Center LUMC, Einthovenweg 20, 2333 ZC Leiden, the Netherlands.
| | - Nina Bakker
- Department of Cell and Chemical Biology, ONCODE institute, Leiden University Medical Center LUMC, Einthovenweg 20, 2333 ZC Leiden, the Netherlands
| | - Lenard M Voortman
- Department of Cell and Chemical Biology, ONCODE institute, Leiden University Medical Center LUMC, Einthovenweg 20, 2333 ZC Leiden, the Netherlands
| | - Roman I Koning
- Electron Microscopy Facility, Department of Cell and Chemical Biology, Leiden University Medical Centre, P.O. Box 9600, 2300 RC Leiden, the Netherlands
| | - Erik Bos
- Electron Microscopy Facility, Department of Cell and Chemical Biology, Leiden University Medical Centre, P.O. Box 9600, 2300 RC Leiden, the Netherlands
| | - Jimmy J L L Akkermans
- Department of Cell and Chemical Biology, ONCODE institute, Leiden University Medical Center LUMC, Einthovenweg 20, 2333 ZC Leiden, the Netherlands
| | - Lennert Janssen
- Department of Cell and Chemical Biology, ONCODE institute, Leiden University Medical Center LUMC, Einthovenweg 20, 2333 ZC Leiden, the Netherlands
| | - Jacques Neefjes
- Department of Cell and Chemical Biology, ONCODE institute, Leiden University Medical Center LUMC, Einthovenweg 20, 2333 ZC Leiden, the Netherlands.
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2
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Wang Z, Wang W, Liu S, Yang F, Liu X, Hua S, Zhu L, Xu A, Hill DL, Wang D, Jiang K, Lippincott-Schwartz J, Liu X, Yao X. CSPP1 stabilizes microtubules by capping both plus and minus ends. J Mol Cell Biol 2024; 16:mjae007. [PMID: 38389254 PMCID: PMC11285173 DOI: 10.1093/jmcb/mjae007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Revised: 12/11/2023] [Accepted: 02/21/2024] [Indexed: 02/24/2024] Open
Abstract
Although the dynamic instability of microtubules (MTs) is fundamental to many cellular functions, quiescent MTs with unattached free distal ends are commonly present and play important roles in various events to power cellular dynamics. However, how these free MT tips are stabilized remains poorly understood. Here, we report that centrosome and spindle pole protein 1 (CSPP1) caps and stabilizes both plus and minus ends of static MTs. Real-time imaging of laser-ablated MTs in live cells showed deposition of CSPP1 at the newly generated MT ends, whose dynamic instability was concomitantly suppressed. Consistently, MT ends in CSPP1-overexpressing cells were hyper-stabilized, while those in CSPP1-depleted cells were much more dynamic. This CSPP1-elicited stabilization of MTs was demonstrated to be achieved by suppressing intrinsic MT catastrophe and restricting polymerization. Importantly, CSPP1-bound MTs were resistant to mitotic centromere-associated kinesin-mediated depolymerization. These findings delineate a previously uncharacterized CSPP1 activity that integrates MT end capping to orchestrate quiescent MTs.
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Affiliation(s)
- Zhikai Wang
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, University of Science and Technology of China School of Life Sciences, Hefei 230027, China
- Anhui Key Laboratory for Cellular Dynamics and Chemical Biology, Hefei National Research Center for Interdisciplinary Sciences at the Microscale, Hefei 230027, China
| | - Wenwen Wang
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, University of Science and Technology of China School of Life Sciences, Hefei 230027, China
- Anhui Key Laboratory for Cellular Dynamics and Chemical Biology, Hefei National Research Center for Interdisciplinary Sciences at the Microscale, Hefei 230027, China
| | - Shuaiyu Liu
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, University of Science and Technology of China School of Life Sciences, Hefei 230027, China
- Anhui Key Laboratory for Cellular Dynamics and Chemical Biology, Hefei National Research Center for Interdisciplinary Sciences at the Microscale, Hefei 230027, China
| | - Fengrui Yang
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, University of Science and Technology of China School of Life Sciences, Hefei 230027, China
- Anhui Key Laboratory for Cellular Dynamics and Chemical Biology, Hefei National Research Center for Interdisciplinary Sciences at the Microscale, Hefei 230027, China
| | - Xu Liu
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, University of Science and Technology of China School of Life Sciences, Hefei 230027, China
- Anhui Key Laboratory for Cellular Dynamics and Chemical Biology, Hefei National Research Center for Interdisciplinary Sciences at the Microscale, Hefei 230027, China
| | - Shasha Hua
- Frontier Science Center for Immunology and Metabolism, Medical Research Institute, Wuhan University, Wuhan 430071, China
| | - Lijuan Zhu
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, University of Science and Technology of China School of Life Sciences, Hefei 230027, China
- Anhui Key Laboratory for Cellular Dynamics and Chemical Biology, Hefei National Research Center for Interdisciplinary Sciences at the Microscale, Hefei 230027, China
| | - Aoqing Xu
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, University of Science and Technology of China School of Life Sciences, Hefei 230027, China
- Anhui Key Laboratory for Cellular Dynamics and Chemical Biology, Hefei National Research Center for Interdisciplinary Sciences at the Microscale, Hefei 230027, China
| | - Donald L Hill
- Comprehensive Cancer Center, University of Alabama, Birmingham, AL 35233, USA
| | - Dongmei Wang
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, University of Science and Technology of China School of Life Sciences, Hefei 230027, China
- Anhui Key Laboratory for Cellular Dynamics and Chemical Biology, Hefei National Research Center for Interdisciplinary Sciences at the Microscale, Hefei 230027, China
| | - Kai Jiang
- Frontier Science Center for Immunology and Metabolism, Medical Research Institute, Wuhan University, Wuhan 430071, China
| | | | - Xing Liu
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, University of Science and Technology of China School of Life Sciences, Hefei 230027, China
- Anhui Key Laboratory for Cellular Dynamics and Chemical Biology, Hefei National Research Center for Interdisciplinary Sciences at the Microscale, Hefei 230027, China
| | - Xuebiao Yao
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, University of Science and Technology of China School of Life Sciences, Hefei 230027, China
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3
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Stephens C, Naghavi MH. The host cytoskeleton: a key regulator of early HIV-1 infection. FEBS J 2024; 291:1835-1848. [PMID: 36527282 PMCID: PMC10272291 DOI: 10.1111/febs.16706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 11/29/2022] [Accepted: 12/16/2022] [Indexed: 12/23/2022]
Abstract
Due to its central role in cell biology, the cytoskeleton is a key regulator of viral infection, influencing nearly every step of the viral life cycle. In this review, we will discuss the role of two key components of the cytoskeleton, namely the actin and microtubule networks in early HIV-1 infection. We will discuss key contributions to processes ranging from the attachment and entry of viral particles at the cell surface to their arrival and import into the nucleus and identify areas where further research into this complex relationship may yield new insights into HIV-1 pathogenesis.
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Affiliation(s)
- Christopher Stephens
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA
| | - Mojgan H. Naghavi
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA
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4
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Danziger M, Xu F, Noble H, Yang P, Roque DM. Tubulin Complexity in Cancer and Metastasis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2024; 1452:21-35. [PMID: 38805123 DOI: 10.1007/978-3-031-58311-7_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
Tubulin plays a fundamental role in cellular function and as the subject for microtubule-active agents in the treatment of ovarian cancer. Microtubule-binding proteins (e.g., tau, MAP1/2/4, EB1, CLIP, TOG, survivin, stathmin) and posttranslational modifications (e.g., tyrosination, deglutamylation, acetylation, glycation, phosphorylation, polyamination) further diversify tubulin functionality and may permit additional opportunities to understand microtubule behavior in disease and to develop microtubule-modifying approaches to combat ovarian cancer. Tubulin-based structures that project from suspended ovarian cancer cells known as microtentacles may contribute to metastatic potential of ovarian cancer cells and could represent an exciting novel therapeutic target.
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Affiliation(s)
- Michael Danziger
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Fuhua Xu
- Division of Gynecologic Oncology, Greenebaum Comprehensive Cancer Center, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Helen Noble
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Peixin Yang
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Dana M Roque
- Division of Gynecologic Oncology, Greenebaum Comprehensive Cancer Center, University of Maryland School of Medicine, Baltimore, MD, USA.
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5
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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: 1] [Impact Index Per Article: 0.5] [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.
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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.
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6
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Fan X, McKenney RJ. Control of motor landing and processivity by the CAP-Gly domain in the KIF13B tail. Nat Commun 2023; 14:4715. [PMID: 37543636 PMCID: PMC10404244 DOI: 10.1038/s41467-023-40425-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Accepted: 07/27/2023] [Indexed: 08/07/2023] Open
Abstract
Microtubules are major components of the eukaryotic cytoskeleton. Posttranslational modifications (PTMs) of tubulin regulates interactions with microtubule-associated proteins (MAPs). One unique PTM is the cyclical removal and re-addition of the C-terminal tyrosine of α-tubulin and MAPs containing CAP-Gly domains specifically recognize tyrosinated microtubules. KIF13B, a long-distance transport kinesin, contains a conserved CAP-Gly domain, but the role of the CAP-Gly domain in KIF13B's motility along microtubules remains unknown. To address this, we investigate the interaction between KIF13B's CAP-Gly domain, and tyrosinated microtubules. We find that KIF13B's CAP-Gly domain influences the initial motor-microtubule interaction, as well as processive motility along microtubules. The effect of the CAP-Gly domain is enhanced when the motor domain is in the ADP state, suggesting an interplay between the N-terminal motor domain and C-terminal CAP-Gly domain. These results reveal that specialized kinesin tail domains play active roles in the initiation and continuation of motor movement.
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Affiliation(s)
- Xiangyu Fan
- Department of Molecular and Cellular Biology, University of California - Davis, 145 Briggs Hall, Davis, CA, 95616, USA
| | - Richard J McKenney
- Department of Molecular and Cellular Biology, University of California - Davis, 145 Briggs Hall, Davis, CA, 95616, USA.
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7
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Radhakrishnan RM, Kizhakkeduth ST, Nair VM, Ayyappan S, Lakshmi RB, Babu N, Prasannajith A, Umeda K, Vijayan V, Kodera N, Manna TK. Kinetochore-microtubule attachment in human cells is regulated by the interaction of a conserved motif of Ska1 with EB1. J Biol Chem 2023; 299:102853. [PMID: 36592928 PMCID: PMC9926122 DOI: 10.1016/j.jbc.2022.102853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 12/16/2022] [Accepted: 12/18/2022] [Indexed: 01/02/2023] Open
Abstract
The kinetochore establishes the linkage between chromosomes and the spindle microtubule plus ends during mitosis. In vertebrates, the spindle-kinetochore-associated (Ska1,2,3) complex stabilizes kinetochore attachment with the microtubule plus ends, but how Ska is recruited to and stabilized at the kinetochore-microtubule interface is not understood. Here, our results show that interaction of Ska1 with the general microtubule plus end-associated protein EB1 through a conserved motif regulates Ska recruitment to kinetochores in human cells. Ska1 forms a stable complex with EB1 via interaction with the motif in its N-terminal disordered loop region. Disruption of this interaction either by deleting or mutating the motif disrupts Ska complex recruitment to kinetochores and induces chromosome alignment defects, but it does not affect Ska complex assembly. Atomic-force microscopy imaging revealed that Ska1 is anchored to the C-terminal region of the EB1 dimer through its loop and thereby promotes formation of extended structures. Furthermore, our NMR data showed that the Ska1 motif binds to the residues in EB1 that are the binding sites of other plus end targeting proteins that are recruited to microtubules by EB1 through a similar conserved motif. Collectively, our results demonstrate that EB1-mediated Ska1 recruitment onto the microtubule serves as a general mechanism for the formation of vertebrate kinetochore-microtubule attachments and metaphase chromosome alignment.
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Affiliation(s)
- Renjith M Radhakrishnan
- School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India
| | - Safwa T Kizhakkeduth
- School of Chemistry, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India
| | - Vishnu M Nair
- School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India
| | - Shine Ayyappan
- School of Chemistry, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India
| | - R Bhagya Lakshmi
- School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India
| | - Neethu Babu
- School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India
| | - Anjaly Prasannajith
- School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India
| | - Kenichi Umeda
- Nano Life Science Institute (WPI-Nano LSI), Kanazawa University, Kakuma-machi, Kanazawa, Japan
| | - Vinesh Vijayan
- School of Chemistry, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India
| | - Noriyuki Kodera
- Nano Life Science Institute (WPI-Nano LSI), Kanazawa University, Kakuma-machi, Kanazawa, Japan
| | - Tapas K Manna
- School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India.
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8
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+TIPs condense on microtubule plus-ends. Nat Cell Biol 2023; 25:12-14. [PMID: 36650376 DOI: 10.1038/s41556-022-01068-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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9
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Zheng Y, Yang M, Chen X, Zhang G, Wan S, Zhang B, Huo J, Liu H. Decreased tubulin-binding cofactor B was involved in the formation disorder of nascent astrocyte processes by regulating microtubule plus-end growth through binding with end-binding proteins 1 and 3 after chronic alcohol exposure. Front Cell Neurosci 2022; 16:989945. [PMID: 36385945 PMCID: PMC9641617 DOI: 10.3389/fncel.2022.989945] [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: 07/09/2022] [Accepted: 09/21/2022] [Indexed: 11/30/2022] Open
Abstract
Fetal alcohol syndrome (FAS) is a neurological disease caused by excessive drinking during pregnancy and characterized by congenital abnormalities in the structure and function of the fetal brain. This study was proposed to provide new insights into the pathogenesis of FAS by revealing the possible mechanisms of alcohol-induced astrocyte injury. First, a chronic alcohol exposure model of astrocytes was established, and the formation disorder was found in astrocyte processes where tubulin-binding cofactor B (TBCB) was decreased or lost, accompanied by disorganized microtubules (MT). Second, to understand the relationship between TBCB reduction and the formation disorder of astrocyte processes, TBCB was silenced or overexpressed. It caused astrocyte processes to retract or lose after silencing, while the processes increased with expending basal part and obtuse tips after overexpressing. It confirmed that TBCB was one of the critical factors for the formation of astrocyte processes through regulating MT plus-end and provided a new view on the pathogenesis of FAS. Third, to explore the mechanism of TBCB regulating MT plus-ends, we first proved end-binding proteins 1 and 3 (EB1/3) were bound at MT plus-ends in astrocytes. Then, through interference experiments, we found that both EB1 and EB3, which formed in heterodimers, were necessary to mediate TBCB binding to MT plus-ends and thus regulated the formation of astrocyte processes. Finally, the regulatory mechanism was studied and the ERK1/2 signaling pathway was found as one of the main pathways regulating the expression of TBCB in astrocytes after alcohol injury.
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Affiliation(s)
- Yin Zheng
- Institute of Neuroscience, Chongqing Medical University, Chongqing, China
- Department of Basic Medicine, Chongqing College of Traditional Chinese Medicine, Chongqing, China
| | - Mei Yang
- Institute of Neuroscience, Chongqing Medical University, Chongqing, China
| | - Xiaoqiao Chen
- Institute of Neuroscience, Chongqing Medical University, Chongqing, China
| | - Gaoli Zhang
- Institute for Viral Hepatitis, Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Shanshan Wan
- Department of Blood Transfusion, Sichuan Cancer Hospital and Institute, Chengdu, China
| | - Bingqiu Zhang
- Institute of Neuroscience, Chongqing Medical University, Chongqing, China
| | - Jiechao Huo
- Fujian Province University Engineering Research Center of Mindong She Medicine, Medical College, Ningde Normal University, Ningde, China
| | - Hui Liu
- Institute of Neuroscience, Chongqing Medical University, Chongqing, China
- *Correspondence: Hui Liu
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10
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Kawano D, Pinter K, Chlebowski M, Petralia RS, Wang YX, Nechiporuk AV, Drerup CM. NudC regulated Lis1 stability is essential for the maintenance of dynamic microtubule ends in axon terminals. iScience 2022; 25:105072. [PMID: 36147950 PMCID: PMC9485903 DOI: 10.1016/j.isci.2022.105072] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 07/26/2022] [Accepted: 08/30/2022] [Indexed: 11/28/2022] Open
Abstract
In the axon terminal, microtubule stability is decreased relative to the axon shaft. The dynamic microtubule plus ends found in the axon terminal have many functions, including serving as a docking site for the Cytoplasmic dynein motor. Here, we report an unexplored function of dynein in microtubule regulation in axon terminals: regulation of microtubule stability. Using a forward genetic screen, we identified a mutant with an abnormal axon terminal structure owing to a loss of function mutation in NudC. We show that, in the axon terminal, NudC is a chaperone for the protein Lis1. Decreased Lis1 in nudc axon terminals causes dynein/dynactin accumulation and increased microtubule stability. Microtubule dynamics can be restored by pharmacologically inhibiting dynein, implicating excess dynein motor function in microtubule stabilization. Together, our data support a model in which local NudC-Lis1 modulation of the dynein motor is critical for the regulation of microtubule stability in the axon terminal. NudC, a dynein regulator, is crucial for axon terminal structure NudC mutation leads to a near complete loss of Lis1 protein in axon terminals Lis1 deficits cause accumulation of dynein and cargo in axon terminals Local elevation of dynein increases axon terminal microtubule stability
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Affiliation(s)
- Dane Kawano
- Unit on Neuronal Cell Biology, National Institute of Child Health & Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Katherine Pinter
- Unit on Neuronal Cell Biology, National Institute of Child Health & Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Madison Chlebowski
- Department of Integrative Biology, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Ronald S Petralia
- Advanced Imaging Core, National Institute of Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD 20892, USA
| | - Ya-Xian Wang
- Advanced Imaging Core, National Institute of Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD 20892, USA
| | - Alex V Nechiporuk
- Department of Cell, Developmental & Cancer Biology, Oregon Health & Science University, Portland, OR 97239, USA
| | - Catherine M Drerup
- Unit on Neuronal Cell Biology, National Institute of Child Health & Human Development, National Institutes of Health, Bethesda, MD 20892, USA.,Department of Integrative Biology, University of Wisconsin-Madison, Madison, WI 53706, USA
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11
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Microtubule cytoskeleton: Revealing new readers of the tubulin code. Curr Biol 2022; 32:R960-R962. [PMID: 36167046 DOI: 10.1016/j.cub.2022.08.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Microtubule networks are thought to be controlled by an elaborate program of tubulin posttranslational modifications and proteins that selectively bind to modified states. A new study identifies proteins that bind tyrosinated tubulin, revealing a novel recognition mechanism.
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12
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MAPRE2 regulates the first meiotic progression in mouse oocytes. Exp Cell Res 2022; 416:113135. [DOI: 10.1016/j.yexcr.2022.113135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 03/30/2022] [Accepted: 04/01/2022] [Indexed: 11/22/2022]
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13
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Asthana J, Cade NI, Normanno D, Lim WM, Surrey T. Gradual compaction of the central spindle decreases its dynamicity in PRC1 and EB1 gene-edited cells. Life Sci Alliance 2021; 4:4/12/e202101222. [PMID: 34580180 PMCID: PMC8500333 DOI: 10.26508/lsa.202101222] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 09/13/2021] [Accepted: 09/15/2021] [Indexed: 11/24/2022] Open
Abstract
Although different anaphase proteins bind with characteristically different strength to the central spindle, the overall central spindle dynamicity slows down as mitosis proceeds. During mitosis, the spindle undergoes morphological and dynamic changes. It reorganizes at the onset of the anaphase when the antiparallel bundler PRC1 accumulates and recruits central spindle proteins to the midzone. Little is known about how the dynamic properties of the central spindle change during its morphological changes in human cells. Using gene editing, we generated human cells that express from their endogenous locus fluorescent PRC1 and EB1 to quantify their native spindle distribution and binding/unbinding turnover. EB1 plus end tracking revealed a general slowdown of microtubule growth, whereas PRC1, similar to its yeast orthologue Ase1, binds increasingly strongly to compacting antiparallel microtubule overlaps. KIF4A and CLASP1 bind more dynamically to the central spindle, but also show slowing down turnover. These results show that the central spindle gradually becomes more stable during mitosis, in agreement with a recent “bundling, sliding, and compaction” model of antiparallel midzone bundle formation in the central spindle during late mitosis.
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Affiliation(s)
- Jayant Asthana
- The Francis Crick Institute, London, UK.,Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | | | - Davide Normanno
- Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - Wei Ming Lim
- The Francis Crick Institute, London, UK.,Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - Thomas Surrey
- The Francis Crick Institute, London, UK .,Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain.,Catalan Institution for Research and Advanced Studies (ICREA), Barcelona, Spain
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14
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Chen J, Kholina E, Szyk A, Fedorov VA, Kovalenko I, Gudimchuk N, Roll-Mecak A. α-tubulin tail modifications regulate microtubule stability through selective effector recruitment, not changes in intrinsic polymer dynamics. Dev Cell 2021; 56:2016-2028.e4. [PMID: 34022132 PMCID: PMC8476856 DOI: 10.1016/j.devcel.2021.05.005] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 04/26/2021] [Accepted: 05/05/2021] [Indexed: 10/21/2022]
Abstract
Microtubules are non-covalent polymers of αβ-tubulin dimers. Posttranslational processing of the intrinsically disordered C-terminal α-tubulin tail produces detyrosinated and Δ2-tubulin. Although these are widely employed as proxies for stable cellular microtubules, their effect (and of the α-tail) on microtubule dynamics remains uncharacterized. Using recombinant, engineered human tubulins, we now find that neither detyrosinated nor Δ2-tubulin affect microtubule dynamics, while the α-tubulin tail is an inhibitor of microtubule growth. Consistent with the latter, molecular dynamics simulations show the α-tubulin tail transiently occluding the longitudinal microtubule polymerization interface. The marked differential in vivo stabilities of the modified microtubule subpopulations, therefore, must result exclusively from selective effector recruitment. We find that tyrosination quantitatively tunes CLIP-170 density at the growing plus end and that CLIP170 and EB1 synergize to selectively upregulate the dynamicity of tyrosinated microtubules. Modification-dependent recruitment of regulators thereby results in microtubule subpopulations with distinct dynamics, a tenet of the tubulin code hypothesis.
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Affiliation(s)
- Jiayi Chen
- Cell Biology and Biophysics Unit, National Institute of Neurological Disorders and Stroke, Bethesda, MD 20892, USA
| | - Ekaterina Kholina
- Department of Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Agnieszka Szyk
- Cell Biology and Biophysics Unit, National Institute of Neurological Disorders and Stroke, Bethesda, MD 20892, USA
| | - Vladimir A Fedorov
- Department of Biology, Lomonosov Moscow State University, Moscow, Russia; Center for Theoretical Problems of Physicochemical Pharmacology, Russian Academy of Sciences, Moscow, Russia
| | - Ilya Kovalenko
- Department of Biology, Lomonosov Moscow State University, Moscow, Russia; Astrakhan State University, Astrakhan 414056, Russia; Sechenov University, Moscow 119991, Russia
| | - Nikita Gudimchuk
- Department of Physics, Lomonosov Moscow State University, Moscow, Russia; Center for Theoretical Problems of Physicochemical Pharmacology, Russian Academy of Sciences, Moscow, Russia; Dmitry Rogachev National Research Center of Pediatric Hematology, Oncology and Immunology, Moscow, Russia.
| | - Antonina Roll-Mecak
- Cell Biology and Biophysics Unit, National Institute of Neurological Disorders and Stroke, Bethesda, MD 20892, USA; Biochemistry and Biophysics Center, National Heart Lung and Blood Institute, Bethesda, MD 20892, USA.
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15
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Naghavi MH. HIV-1 capsid exploitation of the host microtubule cytoskeleton during early infection. Retrovirology 2021; 18:19. [PMID: 34229718 PMCID: PMC8259435 DOI: 10.1186/s12977-021-00563-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 06/29/2021] [Indexed: 01/07/2023] Open
Abstract
Microtubules (MTs) form a filamentous array that provide both structural support and a coordinated system for the movement and organization of macromolecular cargos within the cell. As such, they play a critical role in regulating a wide range of cellular processes, from cell shape and motility to cell polarization and division. The array is radial with filament minus-ends anchored at perinuclear MT-organizing centers and filament plus-ends continuously growing and shrinking to explore and adapt to the intracellular environment. In response to environmental cues, a small subset of these highly dynamic MTs can become stabilized, acquire post-translational modifications and act as specialized tracks for cargo trafficking. MT dynamics and stability are regulated by a subset of highly specialized MT plus-end tracking proteins, known as +TIPs. Central to this is the end-binding (EB) family of proteins which specifically recognize and track growing MT plus-ends to both regulate MT polymerization directly and to mediate the accumulation of a diverse array of other +TIPs at MT ends. Moreover, interaction of EB1 and +TIPs with actin-MT cross-linking factors coordinate changes in actin and MT dynamics at the cell periphery, as well as during the transition of cargos from one network to the other. The inherent structural polarity of MTs is sensed by specialized motor proteins. In general, dynein directs trafficking of cargos towards the minus-end while most kinesins direct movement toward the plus-end. As a pathogenic cargo, HIV-1 uses the actin cytoskeleton for short-range transport most frequently at the cell periphery during entry before transiting to MTs for long-range transport to reach the nucleus. While the fundamental importance of MT networks to HIV-1 replication has long been known, recent work has begun to reveal the underlying mechanistic details by which HIV-1 engages MTs after entry into the cell. This includes mimicry of EB1 by capsid (CA) and adaptor-mediated engagement of dynein and kinesin motors to elegantly coordinate early steps in infection that include MT stabilization, uncoating (conical CA disassembly) and virus transport toward the nucleus. This review discusses recent advances in our understanding of how MT regulators and their associated motors are exploited by incoming HIV-1 capsid during early stages of infection.
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Affiliation(s)
- Mojgan H Naghavi
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
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16
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Wilson ZT, Jiang M, Geng J, Kaur S, Workman SW, Hao J, Bernas T, Tseng GN. Delayed KCNQ1/KCNE1 assembly on the cell surface helps I Ks fulfil its function as a repolarization reserve in the heart. J Physiol 2021; 599:3337-3361. [PMID: 33963564 DOI: 10.1113/jp281773] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 05/04/2021] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS In adult ventricular myocytes, the slow delayed rectifier (IKs ) channels are distributed on the surface sarcolemma, not t-tubules. In adult ventricular myocytes, KCNQ1 and KCNE1 have distinct cell surface and cytoplasmic pools. KCNQ1 and KCNE1 traffic from the endoplasmic reticulum to the plasma membrane by separate routes, and assemble into IKs channels on the cell surface. Liquid chromatography/tandem mass spectrometry applied to affinity-purified KCNQ1 and KCNE1 interacting proteins reveals novel interactors involved in protein trafficking and assembly. Microtubule plus-end binding protein 1 (EB1) binds KCNQ1 preferentially in its dimer form, and promotes KCNQ1 to reach the cell surface. An LQT1-associated mutation, Y111C, reduces KCNQ1 binding to EB1 dimer. ABSTRACT Slow delayed rectifier (IKs ) channels consist of KCNQ1 and KCNE1. IKs functions as a 'repolarization reserve' in the heart by providing extra current for ventricular action potential shortening during β-adrenergic stimulation. There has been much debate about how KCNQ1 and KCNE1 traffic in cells, where they associate to form IKs channels, and the distribution pattern of IKs channels relative to β-adrenergic signalling complex. We used experimental strategies not previously applied to KCNQ1, KCNE1 or IKs , to provide new insights into these issues. 'Retention-using-selected-hook' experiments showed that newly translated KCNE1 constitutively trafficked through the conventional secretory path to the cell surface. KCNQ1 largely stayed in the endoplasmic reticulum, although dynamic KCNQ1 vesicles were observed in the submembrane region. Disulphide-bonded KCNQ1/KCNE1 constructs reported preferential association after they had reached cell surface. An in situ proximity ligation assay detected IKs channels in surface sarcolemma but not t-tubules of ventricular myocytes, similar to the reported location of adenylate cyclase 9/yotiao. Fluorescent protein-tagged KCNQ1 and KCNE1, in conjunction with antibodies targeting their extracellular epitopes, detected distinct cell surface and cytoplasmic pools of both proteins in myocytes. We conclude that, in cardiomyocytes, KCNQ1 and KCNE1 traffic by different routes to surface sarcolemma where they assemble into IKs channels. This mode of delayed channel assembly helps IKs fulfil its function of repolarization reserve. Proteomic experiments revealed a novel KCNQ1 interactor, microtubule plus-end binding protein 1 (EB1). EB1 dimer (active form) bound KCNQ1 and increased its surface level. An LQT1 mutation, Y111C, reduced KCNQ1 binding to EB1 dimer.
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Affiliation(s)
- Zachary T Wilson
- Department of Physiology & Biophysics, Virginia Commonwealth University, Richmond, VA, USA
| | - Min Jiang
- Department of Physiology & Biophysics, Virginia Commonwealth University, Richmond, VA, USA.,Institute of Medicinal biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Jing Geng
- Institute of Medicinal biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Sukhleen Kaur
- Department of Physiology & Biophysics, Virginia Commonwealth University, Richmond, VA, USA
| | - Samuel W Workman
- Department of Physiology & Biophysics, Virginia Commonwealth University, Richmond, VA, USA.,Present address: School of Medicine, Rutgers University, Piscataway, NJ, USA
| | - Jon Hao
- Poochon Scientific, Frederick, MD, USA
| | - Tytus Bernas
- Department of Anatomy & Neurobiology, Virginia Commonwealth University, Richmond, VA, USA
| | - Gea-Ny Tseng
- Department of Physiology & Biophysics, Virginia Commonwealth University, Richmond, VA, USA
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17
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Kesarwani S, Lama P, Chandra A, Reddy PP, Jijumon AS, Bodakuntla S, Rao BM, Janke C, Das R, Sirajuddin M. Genetically encoded live-cell sensor for tyrosinated microtubules. J Cell Biol 2021; 219:152071. [PMID: 32886100 PMCID: PMC7659708 DOI: 10.1083/jcb.201912107] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 04/16/2020] [Accepted: 07/21/2020] [Indexed: 12/21/2022] Open
Abstract
Microtubule cytoskeleton exists in various biochemical forms in different cells due to tubulin posttranslational modifications (PTMs). Tubulin PTMs are known to affect microtubule stability, dynamics, and interaction with MAPs and motors in a specific manner, widely known as tubulin code hypothesis. At present, there exists no tool that can specifically mark tubulin PTMs in living cells, thus severely limiting our understanding of their dynamics and cellular functions. Using a yeast display library, we identified a binder against terminal tyrosine of α-tubulin, a unique PTM site. Extensive characterization validates the robustness and nonperturbing nature of our binder as tyrosination sensor, a live-cell tubulin nanobody specific towards tyrosinated microtubules. Using this sensor, we followed nocodazole-, colchicine-, and vincristine-induced depolymerization events of tyrosinated microtubules in real time and found each distinctly perturbs the microtubule polymer. Together, our work describes a novel tyrosination sensor and its potential applications to study the dynamics of microtubule and their PTM processes in living cells.
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Affiliation(s)
- Shubham Kesarwani
- Centre for Cardiovascular Biology and Diseases, Institute for Stem Cell Science and Regenerative Medicine, Gandhi Krishi Vigyan Kendra Campus, Bangalore, India.,Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Prakash Lama
- Centre for Cardiovascular Biology and Diseases, Institute for Stem Cell Science and Regenerative Medicine, Gandhi Krishi Vigyan Kendra Campus, Bangalore, India.,Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Anchal Chandra
- National Center for Biological Sciences, Tata Institute of Fundamental Research, Gandhi Krishi Vigyan Kendra Campus, Bangalore, India
| | - P Purushotam Reddy
- National Center for Biological Sciences, Tata Institute of Fundamental Research, Gandhi Krishi Vigyan Kendra Campus, Bangalore, India
| | - A S Jijumon
- Institut Curie, Paris Sciences et Lettres University, Centre National de la Recherche Scientifique UMR3348, Orsay, France.,Université Paris Sud, Université Paris-Saclay, Centre National de la Recherche Scientifique UMR3348, Orsay, France
| | - Satish Bodakuntla
- Institut Curie, Paris Sciences et Lettres University, Centre National de la Recherche Scientifique UMR3348, Orsay, France.,Université Paris Sud, Université Paris-Saclay, Centre National de la Recherche Scientifique UMR3348, Orsay, France
| | - Balaji M Rao
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC
| | - Carsten Janke
- Institut Curie, Paris Sciences et Lettres University, Centre National de la Recherche Scientifique UMR3348, Orsay, France.,Université Paris Sud, Université Paris-Saclay, Centre National de la Recherche Scientifique UMR3348, Orsay, France
| | - Ranabir Das
- National Center for Biological Sciences, Tata Institute of Fundamental Research, Gandhi Krishi Vigyan Kendra Campus, Bangalore, India
| | - Minhajuddin Sirajuddin
- Centre for Cardiovascular Biology and Diseases, Institute for Stem Cell Science and Regenerative Medicine, Gandhi Krishi Vigyan Kendra Campus, Bangalore, India
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18
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Ayyappan S, Dharan PS, Krishnan A, Marira RR, Lambert M, Manna TK, Vijayan V. SxIP binding disrupts the constitutive homodimer interface of EB1 and stabilizes EB1 monomer. Biophys J 2021; 120:2019-2029. [PMID: 33737159 DOI: 10.1016/j.bpj.2021.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 02/16/2021] [Accepted: 03/01/2021] [Indexed: 11/16/2022] Open
Abstract
SxIP is a microtubule tip localizing signal found in many +TIP proteins that bind to the hydrophobic cavity of the C-terminal domain of end binding protein 1 (EB1) and then positively regulate the microtubule plus-end tracking of EBs. However, the exact mechanism of microtubule activation of EBs in the presence of SxIP signaling motif is not known. Here, we studied the effect of SxIP peptide on the native conformation of EB1 in solution. Using various NMR experiments, we found that SxIP peptide promoted the dissociation of natively formed EB1 dimer. We also discovered that I224A mutation of EB1 resulted in an unfolded C-terminal domain, which upon binding with the SxIP motif folded to its native structure. Molecular dynamics simulations also confirmed the relative structural stability of EB1 monomer in the SxIP bound state. Residual dipolar couplings and heteronuclear NOE analysis suggested that the binding of SxIP peptide at the C-terminal domain of EB1 decreased the dynamics and conformational flexibility of the N-terminal domain involved in EB1-microtubule interaction. The SxIP-induced disruption of the dimeric interactions in EB1, coupled with the reduction in conformational flexibility of the N-terminal domain of EB1, might facilitate the microtubule association of EB1.
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Affiliation(s)
- Shine Ayyappan
- School of Chemistry, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India
| | - Pooja S Dharan
- School of Chemistry, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India
| | - Arya Krishnan
- School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India
| | - Renjith R Marira
- School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India
| | - Mahil Lambert
- School of Chemistry, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India
| | - Tapas K Manna
- School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India
| | - Vinesh Vijayan
- School of Chemistry, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India.
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19
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Zhang J, Wang H, Liu W, Wang J, Zhang J, Chang X, Huang S, Pang X, Guo J, Wang Q, Zhang W. A novel Q93H missense mutation in DCTN1 caused distal hereditary motor neuropathy type 7B and Perry syndrome from a Chinese family. Neurol Sci 2021; 42:3695-3705. [DOI: 10.1007/s10072-020-04962-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 12/03/2020] [Indexed: 01/20/2023]
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20
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Juanes MA, Fees C, Hoeprich GJ, Jaiswal R, Goode BL. EB1 Directly Regulates APC-Mediated Actin Nucleation. Curr Biol 2020; 30:4763-4772.e8. [PMID: 33007249 PMCID: PMC7726095 DOI: 10.1016/j.cub.2020.08.094] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 07/07/2020] [Accepted: 08/26/2020] [Indexed: 02/01/2023]
Abstract
EB1 was discovered 25 years ago as a binding partner of the tumor suppressor adenomatous polyposis coli (APC) [1]; however, the significance of EB1-APC interactions has remained poorly understood. EB1 functions at the center of a network of microtubule end-tracking proteins (+TIPs) [2-5], and APC binding to EB1 promotes EB1 association with microtubule ends and microtubule stabilization [6, 7]. Whether EB1 interactions govern functions of APC beyond microtubule regulation has not been explored. The C-terminal basic domain of APC (APC-B) directly nucleates actin assembly, and this activity is required in vivo for directed cell migration and for maintaining normal levels of F-actin [8-10]. Here, we show that EB1 binds APC-B and inhibits its actin nucleation function by blocking actin monomer recruitment. Consistent with these biochemical observations, knocking down EB1 increases F-actin levels in cells, and this can be rescued by disrupting APC-mediated actin nucleation. Conversely, overexpressing EB1 decreases F-actin levels and impairs directed cell migration without altering microtubule organization and independent of its direct binding interactions with microtubules. Overall, our results define a new function for EB1 in negatively regulating APC-mediated actin assembly. Combining these findings with other recent studies showing that APC interactions regulate EB1-dependent effects on microtubule dynamics [7], we propose that EB1-APC interactions govern bidirectional cytoskeletal crosstalk by coordinating microtubule and actin dynamics.
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Affiliation(s)
- Maria Angeles Juanes
- Biology Department, Brandeis University, 415 South street, Waltham MA 02454, USA,School of Health and Life Science, Teesside University, Middlesbrough, TS1 3BX, United Kingdom,For correspondence: (Lead Contact),
| | - Colby Fees
- Biology Department, Brandeis University, 415 South street, Waltham MA 02454, USA
| | - Gregory J. Hoeprich
- Biology Department, Brandeis University, 415 South street, Waltham MA 02454, USA
| | - Richa Jaiswal
- Biology Department, Brandeis University, 415 South street, Waltham MA 02454, USA
| | - Bruce L. Goode
- Biology Department, Brandeis University, 415 South street, Waltham MA 02454, USA,For correspondence: (Lead Contact),
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21
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Fourel G, Boscheron C. Tubulin mutations in neurodevelopmental disorders as a tool to decipher microtubule function. FEBS Lett 2020; 594:3409-3438. [PMID: 33064843 DOI: 10.1002/1873-3468.13958] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 09/28/2020] [Accepted: 10/05/2020] [Indexed: 01/08/2023]
Abstract
Malformations of cortical development (MCDs) are a group of severe brain malformations associated with intellectual disability and refractory childhood epilepsy. Human missense heterozygous mutations in the 9 α-tubulin and 10 β-tubulin isoforms forming the heterodimers that assemble into microtubules (MTs) were found to cause MCDs. However, how a single mutated residue in a given tubulin isoform can perturb the entire microtubule population in a neuronal cell remains a crucial question. Here, we examined 85 MCD-associated tubulin mutations occurring in TUBA1A, TUBB2, and TUBB3 and their location in a three-dimensional (3D) microtubule cylinder. Mutations hitting residues exposed on the outer microtubule surface are likely to alter microtubule association with partners, while alteration of intradimer contacts may impair dimer stability and straightness. Other types of mutations are predicted to alter interdimer and lateral contacts, which are responsible for microtubule cohesion, rigidity, and dynamics. MCD-associated tubulin mutations surprisingly fall into all categories, thus providing unexpected insights into how a single mutation may impair microtubule function and elicit dominant effects in neurons.
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22
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Santos da Silva E, Shanmugapriya S, Malikov V, Gu F, Delaney MK, Naghavi MH. HIV-1 capsids mimic a microtubule regulator to coordinate early stages of infection. EMBO J 2020; 39:e104870. [PMID: 32896909 DOI: 10.15252/embj.2020104870] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 08/05/2020] [Accepted: 08/06/2020] [Indexed: 01/09/2023] Open
Abstract
While the microtubule end-binding protein, EB1 facilitates early stages of HIV-1 infection, how it does so remains unclear. Here, we show that beyond its effects on microtubule acetylation, EB1 also indirectly contributes to infection by delivering the plus-end tracking protein (+TIP), cytoplasmic linker protein 170 (CLIP170) to the cell periphery. CLIP170 bound to intact HIV-1 cores or in vitro assembled capsid-nucleocapsid complexes, while EB1 did not. Moreover, unlike EB1 and several other +TIPs, CLIP170 enhanced infection independently of effects on microtubule acetylation. Capsid mutants and imaging revealed that CLIP170 bound HIV-1 cores in a manner distinct from currently known capsid cofactors, influenced by pentamer composition or curvature. Structural analyses revealed an EB-like +TIP-binding motif within the capsid major homology region (MHR) that binds SxIP motifs found in several +TIPs, and variability across this MHR sequence correlated with the extent to which different retroviruses engage CLIP170 to facilitate infection. Our findings provide mechanistic insights into the complex roles of +TIPs in mediating early stages of retroviral infection, and reveal divergent capsid-based EB1 mimicry across retroviral species.
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Affiliation(s)
- Eveline Santos da Silva
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Shanmugapriya Shanmugapriya
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Viacheslav Malikov
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Feng Gu
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - M Keegan Delaney
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Mojgan H Naghavi
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
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23
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Ivashko-Pachima Y, Gozes I. A Novel Microtubule-Tau Association Enhancer and Neuroprotective Drug Candidate: Ac-SKIP. Front Cell Neurosci 2019; 13:435. [PMID: 31632241 PMCID: PMC6779860 DOI: 10.3389/fncel.2019.00435] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Accepted: 09/12/2019] [Indexed: 11/13/2022] Open
Abstract
Activity-dependent neuroprotective protein (ADNP) has been initially discovered through its eight amino acid sequence NAPVSIPQ, which shares SIP motif with SALLRSIPA - a peptide derived from activity-dependent neurotrophic factor (ADNF). Mechanistically, both NAPVSIPQ and SALLRSIPA contain a SIP motif that is identified as a variation of SxIP domain, providing direct interaction with microtubule end-binding proteins (EBs). The peptide SKIP was shown before to provide neuroprotection in vitro and protect against Adnp-related axonal transport deficits in vivo. Here we show, for the first time that SKIP enhanced microtubule dynamics, and prevented Tau-microtubule dissociation and microtubule disassembly induced by the Alzheimer's related zinc intoxication. Furthermore, we introduced, CH3CO-SKIP-NH2 (Ac-SKIP), providing efficacious neuroprotection. Since microtubule - Tau organization and dynamics is central in axonal microtubule cytoskeleton and transport, tightly related to aging processes and Alzheimer's disease, our current study provides a compelling molecular explanation to the in vivo activity of SKIP, placing SKIP motif as a central focus for MT-based neuroprotection in tauopathies with axonal transport implications.
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Affiliation(s)
- Yanina Ivashko-Pachima
- Dr. Diana and Zelman Elton (Elbaum) Laboratory for Molecular Neuroendocrinology, Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine, Sagol School of Neuroscience, Adams Super Center for Brain Studies, Tel Aviv University, Tel Aviv, Israel
| | - Illana Gozes
- Dr. Diana and Zelman Elton (Elbaum) Laboratory for Molecular Neuroendocrinology, Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine, Sagol School of Neuroscience, Adams Super Center for Brain Studies, Tel Aviv University, Tel Aviv, Israel
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24
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Russell RW, Fritz MP, Kraus J, Quinn CM, Polenova T, Gronenborn AM. Accuracy and precision of protein structures determined by magic angle spinning NMR spectroscopy: for some 'with a little help from a friend'. JOURNAL OF BIOMOLECULAR NMR 2019; 73:333-346. [PMID: 30847635 PMCID: PMC6693955 DOI: 10.1007/s10858-019-00233-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 02/06/2019] [Indexed: 06/09/2023]
Abstract
We present a systematic investigation into the attainable accuracy and precision of protein structures determined by heteronuclear magic angle spinning solid-state NMR for a set of four proteins of varied size and secondary structure content. Structures were calculated using synthetically generated random sets of C-C distances up to 7 Å at different degrees of completeness. For single-domain proteins, 9-15 restraints per residue are sufficient to derive an accurate model structure, while maximum accuracy and precision are reached with over 15 restraints per residue. For multi-domain proteins and protein assemblies, additional information on domain orientations, quaternary structure and/or protein shape is needed. As demonstrated for the HIV-1 capsid protein assembly, this can be accomplished by integrating MAS NMR with cryoEM data. In all cases, inclusion of TALOS-derived backbone torsion angles improves the accuracy for small number of restraints, while no further increases are noted for restraint completeness above 40%. In contrast, inclusion of TALOS-derived torsion angle restraints consistently increases the precision of the structural ensemble at all degrees of distance restraint completeness.
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Affiliation(s)
- Ryan W Russell
- Department of Chemistry and Biochemistry, University of Delaware, 19716, Newark, DE, USA
- Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, 1051 Biomedical Science Tower 3, 3501 Fifth Ave, 15261, Pittsburgh, PA, USA
| | - Matthew P Fritz
- Department of Chemistry and Biochemistry, University of Delaware, 19716, Newark, DE, USA
- Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, 1051 Biomedical Science Tower 3, 3501 Fifth Ave, 15261, Pittsburgh, PA, USA
| | - Jodi Kraus
- Department of Chemistry and Biochemistry, University of Delaware, 19716, Newark, DE, USA
- Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, 1051 Biomedical Science Tower 3, 3501 Fifth Ave, 15261, Pittsburgh, PA, USA
| | - Caitlin M Quinn
- Department of Chemistry and Biochemistry, University of Delaware, 19716, Newark, DE, USA
- Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, 1051 Biomedical Science Tower 3, 3501 Fifth Ave, 15261, Pittsburgh, PA, USA
| | - Tatyana Polenova
- Department of Chemistry and Biochemistry, University of Delaware, 19716, Newark, DE, USA.
- Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, 1051 Biomedical Science Tower 3, 3501 Fifth Ave, 15261, Pittsburgh, PA, USA.
| | - Angela M Gronenborn
- Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, 1051 Biomedical Science Tower 3, 3501 Fifth Ave, 15261, Pittsburgh, PA, USA.
- Department of Structural Biology, University of Pittsburgh School of Medicine, 3501 Fifth Ave, 15261, Pittsburgh, PA, USA.
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25
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Jain I, Tran PT. Multiple Motifs Compete for EB-Dependent Microtubule Plus End Binding. Structure 2019; 25:821-822. [PMID: 28591623 DOI: 10.1016/j.str.2017.05.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Microtubule (MT) dynamics are regulated by a plethora of microtubule-associated proteins (MAPs). An important MT regulator is the end binding protein EB, which serves as a scaffold to recruit other MAPs to MT plus ends. In this issue of Structure, Kumar et al. (2017) describe LxxPTPh, a new linear sequence motif that can bind EBs. The finding opens up the possibility of discovering new MT regulators.
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Affiliation(s)
- Ishutesh Jain
- Institut Curie, PSL Research Universities, CNRS, UMR 144, 75005 Paris, France
| | - Phong T Tran
- Institut Curie, PSL Research Universities, CNRS, UMR 144, 75005 Paris, France; Cell and Developmental Biology, University of Pennsylvania, Philadelphia, PA 19104, USA.
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26
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Chen Y, Wang P, Slep KC. Mapping multivalency in the CLIP-170-EB1 microtubule plus-end complex. J Biol Chem 2018; 294:918-931. [PMID: 30455356 DOI: 10.1074/jbc.ra118.006125] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Revised: 11/09/2018] [Indexed: 11/06/2022] Open
Abstract
Cytoplasmic linker protein 170 (CLIP-170) is a microtubule plus-end factor that links vesicles to microtubules and recruits the dynein-dynactin complex to microtubule plus ends. CLIP-170 plus-end localization is end binding 1 (EB1)-dependent. CLIP-170 contains two N-terminal cytoskeleton-associated protein glycine-rich (CAP-Gly) domains flanked by serine-rich regions. The CAP-Gly domains are known EB1-binding domains, and the serine-rich regions have also been implicated in CLIP-170's microtubule plus-end localization mechanism. However, the determinants in these serine-rich regions have not been identified. Here we elucidated multiple EB1-binding modules in the CLIP-170 N-terminal region. Using isothermal titration calorimetry and size-exclusion chromatography, we mapped and biophysically characterized these EB1-binding modules, including the two CAP-Gly domains, a bridging SXIP motif, and a unique array of divergent SXIP-like motifs located N-terminally to the first CAP-Gly domain. We found that, unlike the EB1-binding mode of the CAP-Gly domain in the dynactin-associated protein p150Glued, which dually engages the EB1 C-terminal EEY motif as well as the EB homology domain and sterically occludes SXIP motif binding, the CLIP-170 CAP-Gly domains engage only the EEY motif, enabling the flanking SXIP and SXIP-like motifs to bind the EB homology domain. These multivalent EB1-binding modules provided avidity to the CLIP-170-EB1 interaction, likely clarifying why CLIP-170 preferentially binds EB1 rather than the α-tubulin C-terminal EEY motif. Our finding that CLIP-170 has multiple non-CAP-Gly EB1-binding modules may explain why autoinhibition of CLIP-170 GAP-Gly domains does not fully abrogate its microtubule plus-end localization. This work expands our understanding of EB1-binding motifs and their multivalent networks.
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Affiliation(s)
- Yaodong Chen
- From the Key Laboratory of Resources Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, Xi'an, Shaanxi 710069, China.,the Department of Biology, University of North Carolina, Chapel Hill, North Carolina 27599-3280, and
| | - Ping Wang
- the Department of Neurology, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Kevin C Slep
- the Department of Biology, University of North Carolina, Chapel Hill, North Carolina 27599-3280, and
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27
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Huber S, Karagenc T, Ritler D, Rottenberg S, Woods K. Identification and characterisation of a Theileria annulata proline-rich microtubule and SH3 domain-interacting protein (TaMISHIP) that forms a complex with CLASP1, EB1, and CD2AP at the schizont surface. Cell Microbiol 2018; 20:e12838. [PMID: 29520916 PMCID: PMC6033098 DOI: 10.1111/cmi.12838] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Revised: 02/23/2018] [Accepted: 02/27/2018] [Indexed: 12/20/2022]
Abstract
Theileria annulata is an apicomplexan parasite that modifies the phenotype of its host cell completely, inducing uncontrolled proliferation, resistance to apoptosis, and increased invasiveness. The infected cell thus resembles a cancer cell, and changes to various host cell signalling pathways accompany transformation. Most of the molecular mechanisms leading to Theileria-induced immortalization of leukocytes remain unknown. The parasite dissolves the surrounding host cell membrane soon after invasion and starts interacting with host proteins, ensuring its propagation by stably associating with the host cell microtubule network. By using BioID technology together with fluorescence microscopy and co-immunoprecipitation, we identified a CLASP1/CD2AP/EB1-containing protein complex that surrounds the schizont throughout the host cell cycle and integrates bovine adaptor proteins (CIN85, 14-3-3 epsilon, and ASAP1). This complex also includes the schizont membrane protein Ta-p104 together with a novel secreted T. annulata protein (encoded by TA20980), which we term microtubule and SH3 domain-interacting protein (TaMISHIP). TaMISHIP localises to the schizont surface and contains a functional EB1-binding SxIP motif, as well as functional SH3 domain-binding Px(P/A)xPR motifs that mediate its interaction with CD2AP. Upon overexpression in non-infected bovine macrophages, TaMISHIP causes binucleation, potentially indicative of a role in cytokinesis.
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Affiliation(s)
- Sandra Huber
- Institute for Animal Pathology, Vetsuisse FacultyUniversity of BernBernSwitzerland
| | - Tulin Karagenc
- Department of Parasitology, Faculty of Veterinary MedicineAdnan Menderes UniversityAydinTurkey
| | - Dominic Ritler
- Institute of Parasitology, Vetsuisse FacultyUniversity of BernBernSwitzerland
| | - Sven Rottenberg
- Institute for Animal Pathology, Vetsuisse FacultyUniversity of BernBernSwitzerland
| | - Kerry Woods
- Institute for Animal Pathology, Vetsuisse FacultyUniversity of BernBernSwitzerland
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28
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Gireesh KK, Shine A, Lakshmi RB, Vijayan V, Manna TK. GTP-binding facilitates EB1 recruitment onto microtubules by relieving its auto-inhibition. Sci Rep 2018; 8:9792. [PMID: 29955158 PMCID: PMC6023887 DOI: 10.1038/s41598-018-28056-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Accepted: 06/14/2018] [Indexed: 12/23/2022] Open
Abstract
Microtubule plus end-binding protein, EB1 is a key regulator of microtubule dynamics. Auto-inhibitory interaction in EB1 has previously been shown to inhibit its ability to bind to microtubules and regulate microtubule dynamics. However, the factors that promote its microtubule regulatory activity by over-coming the auto-inhibition are less known. Here, we show that GTP plays a critical role in promoting the microtubule-targeting activity of EB1 by suppressing its auto-inhibition. Our biophysical data demonstrate that GTP binds to EB1 at a distinct site in its conserved N-terminal domain. Detailed analyses reveal that GTP-binding suppresses the intra-molecular inhibitory interaction between the globular N-terminus and the C-terminal coiled-coil domain. We further show that mutation of the GTP-binding site residues in N-terminus weakens the affinity for GTP, but also for the C-terminus, indicating overlapping binding sites. Confocal imaging and biochemical analysis reveal that EB1 localization on the microtubules is significantly increased upon mutations of the GTP-binding site residues. The results demonstrate a unique role of GTP in facilitating EB1 interaction with the microtubules by relieving its intra-molecular inhibition. They also implicate that GTP-binding may regulate the functions of EB1 on the cellular microtubules.
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Affiliation(s)
- K K Gireesh
- School of Biology, Indian Institute of Science Education and Research Thiruvananthapuram, CET Campus, Thiruvananthapuram, 695016, Kerala, India
| | - A Shine
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, CET Campus, Thiruvananthapuram, 695016, Kerala, India
| | - R Bhagya Lakshmi
- School of Biology, Indian Institute of Science Education and Research Thiruvananthapuram, CET Campus, Thiruvananthapuram, 695016, Kerala, India
| | - Vinesh Vijayan
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, CET Campus, Thiruvananthapuram, 695016, Kerala, India.
| | - Tapas K Manna
- School of Biology, Indian Institute of Science Education and Research Thiruvananthapuram, CET Campus, Thiruvananthapuram, 695016, Kerala, India.
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29
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Ye AA, Verma V, Maresca TJ. NOD is a plus end-directed motor that binds EB1 via a new microtubule tip localization sequence. J Cell Biol 2018; 217:3007-3017. [PMID: 29899040 PMCID: PMC6122986 DOI: 10.1083/jcb.201708109] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Revised: 03/14/2018] [Accepted: 05/25/2018] [Indexed: 02/08/2023] Open
Abstract
The mechanism by which the Drosophila chromokinesin NOD promotes chromosome congression is unknown. Ye et al. demonstrate that NOD generates force by two mechanisms: plus end–directed motility and microtubule plus-tip tracking via interaction with EB1 through a newly identified motif. Chromosome congression, the process of positioning chromosomes in the midspindle, promotes the stable transmission of the genome to daughter cells during cell division. Congression is typically facilitated by DNA-associated, microtubule (MT) plus end–directed motors called chromokinesins. The Drosophila melanogaster chromokinesin NOD contributes to congression, but the means by which it does so are unknown in large part because NOD has been classified as a nonmotile, orphan kinesin. It has been postulated that NOD promotes congression, not by conventional plus end–directed motility, but by harnessing polymerization forces by end-tracking on growing MT plus ends via a mechanism that is also uncertain. Here, for the first time, it is demonstrated that NOD possesses MT plus end–directed motility. Furthermore, NOD directly binds EB1 through unconventional EB1-interaction motifs that are similar to a newly characterized MT tip localization sequence. We propose NOD produces congression forces by MT plus end–directed motility and tip-tracking on polymerizing MT plus ends via association with EB1.
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Affiliation(s)
- Anna A Ye
- Biology Department, University of Massachusetts, Amherst, Amherst, MA.,Molecular and Cellular Biology Graduate Program, University of Massachusetts, Amherst, Amherst, MA
| | - Vikash Verma
- Biology Department, University of Massachusetts, Amherst, Amherst, MA
| | - Thomas J Maresca
- Biology Department, University of Massachusetts, Amherst, Amherst, MA .,Molecular and Cellular Biology Graduate Program, University of Massachusetts, Amherst, Amherst, MA
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30
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Stangier MM, Kumar A, Chen X, Farcas AM, Barral Y, Steinmetz MO. Structure-Function Relationship of the Bik1-Bim1 Complex. Structure 2018; 26:607-618.e4. [PMID: 29576319 DOI: 10.1016/j.str.2018.03.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Revised: 02/09/2018] [Accepted: 02/28/2018] [Indexed: 11/30/2022]
Abstract
In budding yeast, the microtubule plus-end tracking proteins Bik1 (CLIP-170) and Bim1 (EB1) form a complex that interacts with partners involved in spindle positioning, including Stu2 and Kar9. Here, we show that the CAP-Gly and coiled-coil domains of Bik1 interact with the C-terminal ETF peptide of Bim1 and the C-terminal tail region of Stu2, respectively. The crystal structures of the CAP-Gly domain of Bik1 (Bik1CG) alone and in complex with an ETF peptide revealed unique, functionally relevant CAP-Gly elements, establishing Bik1CG as a specific C-terminal phenylalanine recognition domain. Unlike the mammalian CLIP-170-EB1 complex, Bik1-Bim1 forms ternary complexes with the EB1-binding motifs SxIP and LxxPTPh, which are present in diverse proteins, including Kar9. Perturbation of the Bik1-Bim1 interaction in vivo affected Bik1 localization and astral microtubule length. Our results provide insight into the role of the Bik1-Bim1 interaction for cell division, and demonstrate that the CLIP-170-EB1 module is evolutionarily flexible.
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Affiliation(s)
- Marcel M Stangier
- Laboratory of Biomolecular Research, Division of Biology and Chemistry, Paul Scherrer Institut, 5232 Villigen PSI, Switzerland
| | - Anil Kumar
- Laboratory of Biomolecular Research, Division of Biology and Chemistry, Paul Scherrer Institut, 5232 Villigen PSI, Switzerland
| | - Xiuzhen Chen
- Institute of Biochemistry, ETH Zürich, 8049 Zürich, Switzerland
| | | | - Yves Barral
- Institute of Biochemistry, ETH Zürich, 8049 Zürich, Switzerland
| | - Michel O Steinmetz
- Laboratory of Biomolecular Research, Division of Biology and Chemistry, Paul Scherrer Institut, 5232 Villigen PSI, Switzerland; University of Basel, Biozentrum, 4056 Basel, Switzerland.
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31
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Xie S, Yang Y, Lin X, Zhou J, Li D, Liu M. Characterization of a novel EB1 acetylation site important for the regulation of microtubule dynamics and cargo recruitment. J Cell Physiol 2018; 233:2581-2589. [PMID: 28777446 DOI: 10.1002/jcp.26133] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 08/03/2017] [Indexed: 01/20/2023]
Abstract
Microtubule plus ends undergo highly dynamic modifications to regulate different aspects of cellular activities. Most microtubule plus-end tracking proteins (+TIPs) are recruited to the microtubule ends by the master loading factor, end-binding protein 1 (EB1). These proteins coordinately regulate microtubule dynamics and cellular plasticity. Acetylation is known to modulate EB1 function; however, the molecular details of EB1 acetylation remain largely unclear. We mapped the acetylation pattern of EB1 and identified several previously uncharacterized sites of EB1 acetylation. We examined the effects of lysine-212 (K212) acetylation and found that acetylation of this site accelerates autophagy-mediated EB1 degradation. By time-lapse microscopy, we found that the acetylation-deficient K212R mutant increased the percentage of fast-growing and long-lived microtubules. Although K212 acetylation did not affect microtubule stability in vitro and the association of EB1 with microtubules, the K212R mutant significantly promoted microtubule regrowth in cells. Coimmunoprecipitation assays further revealed that the K212 site was critical for the recruitment of different +TIP cargoes. These data thus uncover a critical role for a novel EB1 acetylation site in regulating the dynamic structure of microtubules.
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Affiliation(s)
- Songbo Xie
- Shandong Provincial Key Laboratory of Animal Resistance Biology, Institute of Biomedical Sciences, College of Life Sciences, Shandong Normal University, Jinan, Shandong, China
| | - Yang Yang
- State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences, Nankai University, Tianjin, China
| | - Xiaochen Lin
- State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences, Nankai University, Tianjin, China
| | - Jun Zhou
- Shandong Provincial Key Laboratory of Animal Resistance Biology, Institute of Biomedical Sciences, College of Life Sciences, Shandong Normal University, Jinan, Shandong, China
- State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences, Nankai University, Tianjin, China
| | - Dengwen Li
- State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences, Nankai University, Tianjin, China
| | - Min Liu
- Shandong Provincial Key Laboratory of Animal Resistance Biology, Institute of Biomedical Sciences, College of Life Sciences, Shandong Normal University, Jinan, Shandong, China
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32
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Lakshmi RB, Nair VM, Manna TK. Regulators of spindle microtubules and their mechanisms: Living together matters. IUBMB Life 2018; 70:101-111. [DOI: 10.1002/iub.1708] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Accepted: 12/16/2017] [Indexed: 12/23/2022]
Affiliation(s)
- R. Bhagya Lakshmi
- School of Biology; Indian Institute of Science Education and Research, CET Campus; Thiruvananthapuram Kerala India
| | - Vishnu M. Nair
- School of Biology; Indian Institute of Science Education and Research, CET Campus; Thiruvananthapuram Kerala India
| | - Tapas K. Manna
- School of Biology; Indian Institute of Science Education and Research, CET Campus; Thiruvananthapuram Kerala India
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33
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Jha R, Roostalu J, Cade NI, Trokter M, Surrey T. Combinatorial regulation of the balance between dynein microtubule end accumulation and initiation of directed motility. EMBO J 2017; 36:3387-3404. [PMID: 29038173 PMCID: PMC5686545 DOI: 10.15252/embj.201797077] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Revised: 09/04/2017] [Accepted: 09/13/2017] [Indexed: 11/14/2022] Open
Abstract
Cytoplasmic dynein is involved in a multitude of essential cellular functions. Dynein's activity is controlled by the combinatorial action of several regulatory proteins. The molecular mechanism of this regulation is still poorly understood. Using purified proteins, we reconstitute the regulation of the human dynein complex by three prominent regulators on dynamic microtubules in the presence of end binding proteins (EBs). We find that dynein can be in biochemically and functionally distinct pools: either tracking dynamic microtubule plus-ends in an EB-dependent manner or moving processively towards minus ends in an adaptor protein-dependent manner. Whereas both dynein pools share the dynactin complex, they have opposite preferences for binding other regulators, either the adaptor protein Bicaudal-D2 (BicD2) or the multifunctional regulator Lissencephaly-1 (Lis1). BicD2 and Lis1 together control the overall efficiency of motility initiation. Remarkably, dynactin can bias motility initiation locally from microtubule plus ends by autonomous plus-end recognition. This bias is further enhanced by EBs and Lis1. Our study provides insight into the mechanism of dynein regulation by dissecting the distinct functional contributions of the individual members of a dynein regulatory network.
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Affiliation(s)
- Rupam Jha
- The Francis Crick Institute, London, UK
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34
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Targeting SxIP-EB1 interaction: An integrated approach to the discovery of small molecule modulators of dynamic binding sites. Sci Rep 2017; 7:15533. [PMID: 29138501 PMCID: PMC5686072 DOI: 10.1038/s41598-017-15502-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 10/25/2017] [Indexed: 11/09/2022] Open
Abstract
End binding protein 1 (EB1) is a key element in the complex network of protein-protein interactions at microtubule (MT) growing ends, which has a fundamental role in MT polymerisation. EB1 is an important protein target as it is involved in regulating MT dynamic behaviour, and has been associated with several disease states, such as cancer and neuronal diseases. Diverse EB1 binding partners are recognised through a conserved four amino acid motif, (serine-X-isoleucine-proline) which exists within an intrinsically disordered region. Here we report the use of a multidisciplinary computational and experimental approach for the discovery of the first small molecule scaffold which targets the EB1 recruiting domain. This approach includes virtual screening (structure- and ligand-based design) and multiparameter compound selection. Subsequent studies on the selected compounds enabled the elucidation of the NMR structures of the C-terminal domain of EB1 in the free form and complexed with a small molecule. These structures show that the binding site is not preformed in solution, and ligand binding is fundamental for the binding site formation. This work is a successful demonstration of the combination of modelling and experimental methods to enable the discovery of compounds which bind to these challenging systems.
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35
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van der Vaart B, Fischböck J, Mieck C, Pichler P, Mechtler K, Medema RH, Westermann S. TORC1 signaling exerts spatial control over microtubule dynamics by promoting nuclear export of Stu2. J Cell Biol 2017; 216:3471-3484. [PMID: 28972103 PMCID: PMC5674874 DOI: 10.1083/jcb.201606080] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Revised: 02/14/2017] [Accepted: 08/02/2017] [Indexed: 12/30/2022] Open
Abstract
TORC1 regulates microtubule (MT) dynamics in budding yeast, but the key downstream effectors are unknown. van der Vaart et al. show that TORC1 activity before mitosis promotes phosphorylation of the MT polymerase Stu2 near a nuclear export signal, which leads to the nuclear export of Stu2 and reduced nuclear MT growth. The target of rapamycin complex 1 (TORC1) is a highly conserved multiprotein complex that functions in many cellular processes, including cell growth and cell cycle progression. In this study, we define a novel role for TORC1 as a critical regulator of nuclear microtubule (MT) dynamics in the budding yeast Saccharomyces cerevisiae. This activity requires interactions between EB1 and CLIP-170 plus end–tracking protein (+TIP) family members with the TORC1 subunit Kog1/Raptor, which in turn allow the TORC1 proximal kinase Sch9/S6K1 to regulate the MT polymerase Stu2/XMAP215. Sch9-dependent phosphorylation of Stu2 adjacent to a nuclear export signal prevents nuclear accumulation of Stu2 before cells enter mitosis. Mutants impaired in +TIP–TORC1 interactions or Stu2 nuclear export show increased nuclear but not cytoplasmic MT length and display nuclear fusion, spindle positioning, and elongation kinetics defects. Our results reveal key mechanisms by which TORC1 signaling controls Stu2 localization and thereby contributes to proper MT cytoskeletal organization in interphase and mitosis.
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Affiliation(s)
- Babet van der Vaart
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria .,Division of Cell Biology, The Netherlands Cancer Institute, Amsterdam, Netherlands
| | - Josef Fischböck
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria
| | - Christine Mieck
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria
| | - Peter Pichler
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria
| | - Karl Mechtler
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria
| | - René H Medema
- Division of Cell Biology, The Netherlands Cancer Institute, Amsterdam, Netherlands
| | - Stefan Westermann
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria .,Department of Molecular Genetics, Faculty of Biology, Center for Medical Biotechnology, University of Duisburg-Essen, Essen, Germany
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36
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Aiken J, Buscaglia G, Bates EA, Moore JK. The α-Tubulin gene TUBA1A in Brain Development: A Key Ingredient in the Neuronal Isotype Blend. J Dev Biol 2017; 5. [PMID: 29057214 PMCID: PMC5648057 DOI: 10.3390/jdb5030008] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Microtubules are dynamic cytoskeletal polymers that mediate numerous, essential functions such as axon and dendrite growth and neuron migration throughout brain development. In recent years, sequencing has revealed dominant mutations that disrupt the tubulin protein building blocks of microtubules. These tubulin mutations lead to a spectrum of devastating brain malformations, complex neurological and physical phenotypes, and even fatality. The most common tubulin gene mutated is the α-tubulin gene TUBA1A, which is the most prevalent α-tubulin gene expressed in post-mitotic neurons. The normal role of TUBA1A during neuronal maturation, and how mutations alter its function to produce the phenotypes observed in patients, remains unclear. This review synthesizes current knowledge of TUBA1A function and expression during brain development, and the brain malformations caused by mutations in TUBA1A.
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Affiliation(s)
- Jayne Aiken
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, MS8108, 12801 E 17th Ave, Aurora, CO 80045, USA;
| | - Georgia Buscaglia
- Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; (G.B.); (E.A.B.)
| | - Emily A. Bates
- Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; (G.B.); (E.A.B.)
| | - Jeffrey K. Moore
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, MS8108, 12801 E 17th Ave, Aurora, CO 80045, USA;
- Correspondence: ; Tel.: +1-303-724-6198; Fax: +1-303-724-3420
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37
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Qu X, Yuan FN, Corona C, Pasini S, Pero ME, Gundersen GG, Shelanski ML, Bartolini F. Stabilization of dynamic microtubules by mDia1 drives Tau-dependent Aβ 1-42 synaptotoxicity. J Cell Biol 2017; 216:3161-3178. [PMID: 28877993 PMCID: PMC5626542 DOI: 10.1083/jcb.201701045] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Revised: 06/15/2017] [Accepted: 07/26/2017] [Indexed: 01/17/2023] Open
Abstract
Oligomeric Amyloid β1-42 (Aβ) plays a crucial synaptotoxic role in Alzheimer's disease, and hyperphosphorylated tau facilitates Aβ toxicity. The link between Aβ and tau, however, remains controversial. In this study, we find that in hippocampal neurons, Aβ acutely induces tubulin posttranslational modifications (PTMs) and stabilizes dynamic microtubules (MTs) by reducing their catastrophe frequency. Silencing or acute inhibition of the formin mDia1 suppresses these activities and corrects the synaptotoxicity and deficits of axonal transport induced by Aβ. We explored the mechanism of rescue and found that stabilization of dynamic MTs promotes tau-dependent loss of dendritic spines and tau hyperphosphorylation. Collectively, these results uncover a novel role for mDia1 in Aβ-mediated synaptotoxicity and demonstrate that inhibition of MT dynamics and accumulation of PTMs are driving factors for the induction of tau-mediated neuronal damage.
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Affiliation(s)
- Xiaoyi Qu
- Department of Pathology, Anatomy and Cell Biology, Columbia University, New York, NY
| | - Feng Ning Yuan
- Department of Pathology, Anatomy and Cell Biology, Columbia University, New York, NY
| | - Carlo Corona
- Department of Pathology, Anatomy and Cell Biology, Columbia University, New York, NY
| | - Silvia Pasini
- Department of Pathology, Anatomy and Cell Biology, Columbia University, New York, NY
| | - Maria Elena Pero
- Department of Pathology, Anatomy and Cell Biology, Columbia University, New York, NY.,Department of Veterinary Medicine and Animal Production, University of Naples Federico II, Naples, Italy
| | - Gregg G Gundersen
- Department of Pathology, Anatomy and Cell Biology, Columbia University, New York, NY
| | - Michael L Shelanski
- Department of Pathology, Anatomy and Cell Biology, Columbia University, New York, NY
| | - Francesca Bartolini
- Department of Pathology, Anatomy and Cell Biology, Columbia University, New York, NY
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38
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Schmidt R, Fielmich LE, Grigoriev I, Katrukha EA, Akhmanova A, van den Heuvel S. Two populations of cytoplasmic dynein contribute to spindle positioning in C. elegans embryos. J Cell Biol 2017; 216:2777-2793. [PMID: 28739679 PMCID: PMC5584144 DOI: 10.1083/jcb.201607038] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Revised: 05/08/2017] [Accepted: 06/28/2017] [Indexed: 12/14/2022] Open
Abstract
The position of the mitotic spindle is tightly controlled in animal cells as it determines the plane and orientation of cell division. Contacts between cytoplasmic dynein and astral microtubules (MTs) at the cell cortex generate pulling forces that position the spindle. An evolutionarily conserved Gα-GPR-1/2Pins/LGN-LIN-5Mud/NuMA cortical complex interacts with dynein and is required for pulling force generation, but the dynamics of this process remain unclear. In this study, by fluorescently labeling endogenous proteins in Caenorhabditis elegans embryos, we show that dynein exists in two distinct cortical populations. One population directly depends on LIN-5, whereas the other is concentrated at MT plus ends and depends on end-binding (EB) proteins. Knockout mutants lacking all EBs are viable and fertile and display normal pulling forces and spindle positioning. However, EB protein-dependent dynein plus end tracking was found to contribute to force generation in embryos with a partially perturbed dynein function, indicating the existence of two mechanisms that together create a highly robust force-generating system.
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Affiliation(s)
- Ruben Schmidt
- Developmental Biology, Department of Biology, Faculty of Sciences, Utrecht University, Utrecht, Netherlands
- Cell Biology, Department of Biology, Faculty of Sciences, Utrecht University, Utrecht, Netherlands
| | - Lars-Eric Fielmich
- Developmental Biology, Department of Biology, Faculty of Sciences, Utrecht University, Utrecht, Netherlands
| | - Ilya Grigoriev
- Cell Biology, Department of Biology, Faculty of Sciences, Utrecht University, Utrecht, Netherlands
| | - Eugene A Katrukha
- Cell Biology, Department of Biology, Faculty of Sciences, Utrecht University, Utrecht, Netherlands
| | - Anna Akhmanova
- Cell Biology, Department of Biology, Faculty of Sciences, Utrecht University, Utrecht, Netherlands
| | - Sander van den Heuvel
- Developmental Biology, Department of Biology, Faculty of Sciences, Utrecht University, Utrecht, Netherlands
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39
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Yang C, Wu J, de Heus C, Grigoriev I, Liv N, Yao Y, Smal I, Meijering E, Klumperman J, Qi RZ, Akhmanova A. EB1 and EB3 regulate microtubule minus end organization and Golgi morphology. J Cell Biol 2017; 216:3179-3198. [PMID: 28814570 PMCID: PMC5626540 DOI: 10.1083/jcb.201701024] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Revised: 06/08/2017] [Accepted: 07/18/2017] [Indexed: 12/19/2022] Open
Abstract
End-binding proteins regulate the dynamics and function of microtubule plus ends by recruiting a plethora of diverse factors. Yang et al. show that EB1 and EB3 also affect microtubule minus ends by participating in their attachment to Golgi membranes. This function is important for cell polarity and migration. End-binding proteins (EBs) are the core components of microtubule plus end tracking protein complexes, but it is currently unknown whether they are essential for mammalian microtubule organization. Here, by using CRISPR/Cas9-mediated knockout technology, we generated stable cell lines lacking EB2 and EB3 and the C-terminal partner-binding half of EB1. These cell lines show only mild defects in cell division and microtubule polymerization. However, the length of CAMSAP2-decorated stretches at noncentrosomal microtubule minus ends in these cells is reduced, microtubules are detached from Golgi membranes, and the Golgi complex is more compact. Coorganization of microtubules and Golgi membranes depends on the EB1/EB3–myomegalin complex, which acts as membrane–microtubule tether and counteracts tight clustering of individual Golgi stacks. Disruption of EB1 and EB3 also perturbs cell migration, polarity, and the distribution of focal adhesions. EB1 and EB3 thus affect multiple interphase processes and have a major impact on microtubule minus end organization.
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Affiliation(s)
- Chao Yang
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, Utrecht, Netherlands
| | - Jingchao Wu
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, Utrecht, Netherlands
| | - Cecilia de Heus
- Department of Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht, Netherlands
| | - Ilya Grigoriev
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, Utrecht, Netherlands
| | - Nalan Liv
- Department of Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht, Netherlands
| | - Yao Yao
- Department of Medical Informatics, Biomedical Imaging Group Rotterdam, Erasmus University Medical Center, Rotterdam, Netherlands.,Department of Radiology, Biomedical Imaging Group Rotterdam, Erasmus University Medical Center, Rotterdam, Netherlands
| | - Ihor Smal
- Department of Medical Informatics, Biomedical Imaging Group Rotterdam, Erasmus University Medical Center, Rotterdam, Netherlands.,Department of Radiology, Biomedical Imaging Group Rotterdam, Erasmus University Medical Center, Rotterdam, Netherlands
| | - Erik Meijering
- Department of Medical Informatics, Biomedical Imaging Group Rotterdam, Erasmus University Medical Center, Rotterdam, Netherlands.,Department of Radiology, Biomedical Imaging Group Rotterdam, Erasmus University Medical Center, Rotterdam, Netherlands
| | - Judith Klumperman
- Department of Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht, Netherlands
| | - Robert Z Qi
- Division of Life Science, The Hong Kong University of Science and Technology, Kowloon, Hong Kong, China
| | - Anna Akhmanova
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, Utrecht, Netherlands
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40
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Shi X, Sun X. Regulation of paclitaxel activity by microtubule-associated proteins in cancer chemotherapy. Cancer Chemother Pharmacol 2017; 80:909-917. [PMID: 28741098 DOI: 10.1007/s00280-017-3398-2] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2017] [Accepted: 07/17/2017] [Indexed: 11/30/2022]
Abstract
Microtubules, highly dynamic components of the cytoskeleton, participate in diverse cellular activities such as mitosis, cell migration, and intracellular trafficking. Dysregulation of microtubule dynamics contributes to the development of serious diseases, including cancer. The dynamic properties and functions of microtubule network are regulated by microtubule-associated proteins. Paclitaxel, an anti-microtubule agent of the taxane family, has shown a success in clinical treatment of many cancer patients. However, the variable response activity of patients and acquired resistance to paclitaxel limit the clinical use of the drug. Accumulating studies show that microtubule-associated proteins can regulate paclitaxel sensitivity in a wide range of cancer types. In this review, we will describe the roles of various microtubule-associated proteins in the regulation of paclitaxel in cancers. Particularly, we will focus on the modulation of centrosomal proteins in paclitaxel resistance. Improved understandings of how these proteins act might predict treatment responses and provide insights into more rational chemotherapeutic regimens in clinical practice.
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Affiliation(s)
- Xingjuan Shi
- Key Laboratory of Developmental Genes and Human Disease, Institute of Life Sciences, Southeast University, Nanjing, 210096, China.
| | - Xiaoou Sun
- School of Bioscience and Bioengineering, South China University of Technology, Guangzhou, 510006, China.
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41
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Bonjack-Shterengartz M, Avnir D. The enigma of the near-symmetry of proteins: Domain swapping. PLoS One 2017; 12:e0180030. [PMID: 28708874 PMCID: PMC5510828 DOI: 10.1371/journal.pone.0180030] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 06/08/2017] [Indexed: 01/25/2023] Open
Abstract
The majority of proteins form oligomers which have rotational symmetry. Literature has suggested many functional advantages that the symmetric packing offers. Yet, despite these advantages, the vast majority of protein oligomers are only nearly symmetric. A key question in the field of proteins structure is therefore, if symmetry is so advantageous, why do oligomers settle for aggregates that do not maximize that structural property? The answer to that question is apparently multi-parametric, and involves distortions at the interaction zones of the monomer units of the oligomer in order to minimize the free energy, the dynamics of the protein, the effects of surroundings parameters, and the mechanism of oligomerization. The study of this problem is in its infancy: Only the first parameter has been explored so far. Here we focus on the last parameter-the mechanism of formation. To test this effect we have selected to focus on the domain swapping mechanism of oligomerization, by which oligomers form in a mechanism that swaps identical portions of monomeric units, resulting in an interwoven oligomer. We are using continuous symmetry measures to analyze in detail the oligomer formed by this mechanism, and found, that without exception, in all analyzed cases, perfect symmetry is given away, and we are able to identify that the main burden of distortion lies in the hinge regions that connect the swapped portions. We show that the continuous symmetry analysis method clearly identifies the hinge region of swapped domain proteins-considered to be a non-trivial task. We corroborate our conclusion about the central role of the hinge region in affecting the symmetry of the oligomers, by a special probability analysis developed particularly for that purpose.
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Affiliation(s)
- Maayan Bonjack-Shterengartz
- Institute of Chemistry and the Lise Meitner Minerva Center for Computational Quantum Chemistry, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - David Avnir
- Institute of Chemistry and the Lise Meitner Minerva Center for Computational Quantum Chemistry, The Hebrew University of Jerusalem, Jerusalem, Israel
- * E-mail:
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42
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Barbosa DJ, Duro J, Prevo B, Cheerambathur DK, Carvalho AX, Gassmann R. Dynactin binding to tyrosinated microtubules promotes centrosome centration in C. elegans by enhancing dynein-mediated organelle transport. PLoS Genet 2017; 13:e1006941. [PMID: 28759579 PMCID: PMC5552355 DOI: 10.1371/journal.pgen.1006941] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 08/10/2017] [Accepted: 07/25/2017] [Indexed: 12/01/2022] Open
Abstract
The microtubule-based motor dynein generates pulling forces for centrosome centration and mitotic spindle positioning in animal cells. How the essential dynein activator dynactin regulates these functions of the motor is incompletely understood. Here, we dissect the role of dynactin's microtubule binding activity, located in the p150 CAP-Gly domain and an adjacent basic patch, in the C. elegans zygote. Analysis of p150 mutants engineered by genome editing suggests that microtubule tip tracking of dynein-dynactin is dispensable for targeting the motor to the cell cortex and for generating robust cortical pulling forces. Instead, mutations in p150's CAP-Gly domain inhibit cytoplasmic pulling forces responsible for centration of centrosomes and attached pronuclei. The centration defects are mimicked by mutations of α-tubulin's C-terminal tyrosine, and both p150 CAP-Gly and tubulin tyrosine mutants decrease the frequency of early endosome transport from the cell periphery towards centrosomes during centration. Our results suggest that p150 GAP-Gly domain binding to tyrosinated microtubules promotes initiation of dynein-mediated organelle transport in the dividing one-cell embryo, and that this function of p150 is critical for generating cytoplasmic pulling forces for centrosome centration.
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Affiliation(s)
- Daniel J. Barbosa
- Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
- Instituto de Investigação e Inovação em Saúde (I3S), Universidade do Porto, Porto, Portugal
| | - Joana Duro
- Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
- Instituto de Investigação e Inovação em Saúde (I3S), Universidade do Porto, Porto, Portugal
| | - Bram Prevo
- Ludwig Institute for Cancer Research/Dept of Cellular & Molecular Medicine UCSD, La Jolla, CA, United States of America
| | - Dhanya K. Cheerambathur
- Ludwig Institute for Cancer Research/Dept of Cellular & Molecular Medicine UCSD, La Jolla, CA, United States of America
| | - Ana X. Carvalho
- Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
- Instituto de Investigação e Inovação em Saúde (I3S), Universidade do Porto, Porto, Portugal
| | - Reto Gassmann
- Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
- Instituto de Investigação e Inovação em Saúde (I3S), Universidade do Porto, Porto, Portugal
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43
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Konno T, Ross OA, Teive HAG, Sławek J, Dickson DW, Wszolek ZK. DCTN1-related neurodegeneration: Perry syndrome and beyond. Parkinsonism Relat Disord 2017. [PMID: 28625595 DOI: 10.1016/j.parkreldis.2017.06.004] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Perry syndrome (PS) is a rare hereditary neurodegenerative disease characterized by autosomal dominant parkinsonism, psychiatric symptoms, weight loss, central hypoventilation, and distinct TDP-43 pathology. The mutated causative gene for PS is DCTN1, which encodes the dynactin subunit p150Glued. Dynactin is a motor protein involved in axonal transport; the p150Glued subunit has a critical role in the overall function. Since the discovery of DCTN1 in PS, it has been increasingly recognized that DCTN1 mutations can exhibit more diverse phenotypes than previously thought. Progressive supranuclear palsy- and/or frontotemporal dementia-like phenotypes have been associated with the PS phenotypes. In addition, DCTN1 mutations were identified in a family with motor-neuron disease before the discovery in PS. In this review, we analyze the clinical and genetic aspects of DCTN1-related neurodegeneration and discuss its pathogenesis. We also describe three families with PS, Canadian, Polish, and Brazilian. DCTN1 mutation was newly identified in two of them, the Canadian and Polish families. The Canadian family was first described in late 1970's but was never genetically tested. We recently had the opportunity to evaluate this family and to test the gene status of an affected family member. The Polish family is newly identified and is the first PS family in Poland. Although still rare, DCTN1-related neurodegeneration needs to be considered in a differential diagnosis of parkinsonian disorders, frontotemporal dementia, and motor-neuron diseases, especially if there is family history.
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Affiliation(s)
- Takuya Konno
- Department of Neurology, Mayo Clinic, 4500 San Pablo Road, Jacksonville, FL, 32224, USA
| | - Owen A Ross
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Road, Jacksonville, FL, 32224, USA
| | - Hélio A G Teive
- Movement Disorders Unit, Neurology Service, Hospital de Clínicas, Federal University of Paraná, Rua General Carneiro 1103/102, Centro, Curitiba, PR, 80060-150, Brazil
| | - Jarosław Sławek
- Department of Neurological-Psychiatric Nursing, Medical University of Gdansk, Poland; Department of Neurology, St. Adalbert Hospital, Copernicus Ltd., Gdansk, Poland
| | - Dennis W Dickson
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Road, Jacksonville, FL, 32224, USA
| | - Zbigniew K Wszolek
- Department of Neurology, Mayo Clinic, 4500 San Pablo Road, Jacksonville, FL, 32224, USA.
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44
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Estrem C, Fees CP, Moore JK. Dynein is regulated by the stability of its microtubule track. J Cell Biol 2017; 216:2047-2058. [PMID: 28572117 PMCID: PMC5496616 DOI: 10.1083/jcb.201611105] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Revised: 03/24/2017] [Accepted: 05/04/2017] [Indexed: 12/23/2022] Open
Abstract
How dynein motors accurately move cargoes is an important question. In budding yeast, dynein moves the mitotic spindle to the predetermined site of cytokinesis by pulling on astral microtubules. In this study, using high-resolution imaging in living cells, we discover that spindle movement is regulated by changes in microtubule plus-end dynamics that occur when dynein generates force. Mutants that increase plus-end stability increase the frequency and duration of spindle movements, causing positioning errors. We find that dynein plays a primary role in regulating microtubule dynamics by destabilizing microtubules. In contrast, the dynactin complex counteracts dynein and stabilizes microtubules through a mechanism involving the shoulder subcomplex and the cytoskeletal-associated protein glycine-rich domain of Nip100/p150glued Our results support a model in which dynein destabilizes its microtubule substrate by using its motility to deplete dynactin from the plus end. We propose that interplay among dynein, dynactin, and the stability of the microtubule substrate creates a mechanism that regulates accurate spindle positioning.
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Affiliation(s)
- Cassi Estrem
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, CO
| | - Colby P Fees
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, CO
| | - Jeffrey K Moore
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, CO
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45
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Short Linear Sequence Motif LxxPTPh Targets Diverse Proteins to Growing Microtubule Ends. Structure 2017; 25:924-932.e4. [DOI: 10.1016/j.str.2017.04.010] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Revised: 04/06/2017] [Accepted: 04/28/2017] [Indexed: 11/23/2022]
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46
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Baumbach J, Murthy A, McClintock MA, Dix CI, Zalyte R, Hoang HT, Bullock SL. Lissencephaly-1 is a context-dependent regulator of the human dynein complex. eLife 2017; 6. [PMID: 28406398 PMCID: PMC5413349 DOI: 10.7554/elife.21768] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Accepted: 04/11/2017] [Indexed: 01/19/2023] Open
Abstract
The cytoplasmic dynein-1 (dynein) motor plays a central role in microtubule organisation and cargo transport. These functions are spatially regulated by association of dynein and its accessory complex dynactin with dynamic microtubule plus ends. Here, we elucidate in vitro the roles of dynactin, end-binding protein-1 (EB1) and Lissencephaly-1 (LIS1) in the interaction of end tracking and minus end-directed human dynein complexes with these sites. LIS1 promotes dynactin-dependent tracking of dynein on both growing and shrinking plus ends. LIS1 also increases the frequency and velocity of processive dynein movements that are activated by complex formation with dynactin and a cargo adaptor. This stimulatory effect of LIS1 contrasts sharply with its documented ability to inhibit the activity of isolated dyneins. Collectively, our findings shed light on how mammalian dynein complexes associate with dynamic microtubules and help clarify how LIS1 promotes the plus-end localisation and cargo transport functions of dynein in vivo. DOI:http://dx.doi.org/10.7554/eLife.21768.001
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Affiliation(s)
- Janina Baumbach
- Division of Cell Biology, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
| | - Andal Murthy
- Division of Cell Biology, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom.,Division of Structural Studies, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
| | - Mark A McClintock
- Division of Cell Biology, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
| | - Carly I Dix
- Division of Cell Biology, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
| | - Ruta Zalyte
- Division of Structural Studies, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
| | - Ha Thi Hoang
- Division of Cell Biology, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
| | - Simon L Bullock
- Division of Cell Biology, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
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47
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Fong KW, Au FKC, Jia Y, Yang S, Zhou L, Qi RZ. Microtubule plus-end tracking of end-binding protein 1 (EB1) is regulated by CDK5 regulatory subunit-associated protein 2. J Biol Chem 2017; 292:7675-7687. [PMID: 28320860 DOI: 10.1074/jbc.m116.759746] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Revised: 03/15/2017] [Indexed: 01/08/2023] Open
Abstract
Microtubules are polar cytoskeleton filaments that extend via growth at their plus ends. Microtubule plus-end-tracking proteins (+TIPs) accumulate at these growing plus ends to control microtubule dynamics and attachment. The +TIP end-binding protein 1 (EB1) and its homologs possess an autonomous plus-end-tracking mechanism and interact with other known +TIPs, which then recruit those +TIPs to the growing plus ends. A major +TIP class contains the SXIP (Ser-X-Ile-Pro, with X denoting any amino acid residue) motif, known to interact with EB1 and its homologs for plus-end tracking, but the role of SXIP in regulating EB1 activities is unclear. We show here that an interaction of EB1 with the SXIP-containing +TIP CDK5 regulatory subunit-associated protein 2 (CDK5RAP2) regulates several EB1 activities, including microtubule plus-end tracking, dynamics at microtubule plus ends, microtubule and α/β-tubulin binding, and microtubule polymerization. The SXIP motif fused with a dimerization domain from CDK5RAP2 significantly enhanced EB1 plus-end-tracking and microtubule-polymerizing and bundling activities, but the SXIP motif alone failed to do so. An SXIP-binding-deficient EB1 mutant displayed significantly lower microtubule plus-end tracking than the wild-type protein in transfected cells. These results suggest that EB1 cooperates with CDK5RAP2 and perhaps other SXIP-containing +TIPs in tracking growing microtubule tips. We also generated plus-end-tracking chimeras of CDK5RAP2 and the adenomatous polyposis coli protein (APC) and found that overexpression of the dimerization domains interfered with microtubule plus-end tracking of their respective SXIP-containing chimeras. Our results suggest that disruption of SXIP dimerization enables detailed investigations of microtubule plus-end-associated functions of individual SXIP-containing +TIPs.
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Affiliation(s)
- Ka-Wing Fong
- From the Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Franco K C Au
- From the Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Yue Jia
- From the Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Shaozhong Yang
- From the Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Liying Zhou
- From the Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Robert Z Qi
- From the Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
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48
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Guo C, Hou G, Lu X, Polenova T. Mapping protein-protein interactions by double-REDOR-filtered magic angle spinning NMR spectroscopy. JOURNAL OF BIOMOLECULAR NMR 2017; 67:95-108. [PMID: 28120201 PMCID: PMC6258002 DOI: 10.1007/s10858-016-0086-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 12/25/2016] [Indexed: 05/03/2023]
Abstract
REDOR-based experiments with simultaneous 1H-13C and 1H-15N dipolar dephasing are explored for investigating intermolecular protein-protein interfaces in complexes formed by a U-13C,15N-labeled protein and its natural abundance binding partner. The application of a double-REDOR filter (dREDOR) results in a complete dephasing of proton magnetization in the U-13C,15N-enriched molecule while the proton magnetization of the unlabeled binding partner is not dephased. This retained proton magnetization is then transferred across the intermolecular interface by 1H-13C or 1H-15N cross polarization, permitting to establish the residues of the U-13C,15N-labeled protein, which constitute the binding interface. To assign the interface residues, this dREDOR-CPMAS element is incorporated as a building block into 13C-13C correlation experiments. We established the validity of this approach on U-13C,15N-histidine and on a structurally characterized complex of dynactin's U-13C,15N-CAP-Gly domain with end-binding protein 1 (EB1). The approach introduced here is broadly applicable to the analysis of intermolecular interfaces when one of the binding partners in a complex cannot be isotopically labeled.
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Affiliation(s)
- Changmiao Guo
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, 19716, USA
| | - Guangjin Hou
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, 19716, USA.
| | - Xingyu Lu
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, 19716, USA
| | - Tatyana Polenova
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, 19716, USA.
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49
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Shukla N, Osmani AH, Osmani SA. Microtubules are reversibly depolymerized in response to changing gaseous microenvironments within Aspergillus nidulans biofilms. Mol Biol Cell 2017; 28:634-644. [PMID: 28057761 PMCID: PMC5328622 DOI: 10.1091/mbc.e16-10-0750] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Revised: 12/16/2016] [Accepted: 12/29/2016] [Indexed: 12/20/2022] Open
Abstract
How microtubules (MTs) are regulated during fungal biofilm formation is unknown. By tracking MT +end-binding proteins (+TIPS) in Aspergillus nidulans, we find that MTs are regulated to depolymerize within forming fungal biofilms. During this process, EB1, dynein, and ClipA form transient fibrous and then bar-like structures, novel configurations for +TIPS. Cells also respond in an autonomous manner, with cells separated by a septum able to maintain different MT dynamics. Surprisingly, all cells with depolymerized MTs rapidly repolymerize their MTs after air exchange above the static culture medium of biofilms. Although the specific gasotransmitter for this biofilm response is not known, we find that addition of hydrogen sulfide gas to growing cells recapitulates all aspects of reversible MT depolymerization and transient formation of +TIPs bars. However, as biofilms mature, physical removal of part of the biofilm is required to promote MT repolymerization, which occurs at the new biofilm edge. We further show MT depolymerization within biofilms is regulated by the SrbA hypoxic transcription factor and that without SrbA, MTs are maintained as biofilms form. This reveals a new mode of MT regulation in response to changing gaseous biofilm microenvironments, which could contribute to the unique characteristics of fungal biofilms in medical and industrial settings.
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Affiliation(s)
- Nandini Shukla
- Ohio State Biochemistry Program, The Ohio State University, Columbus, OH 43210.,Department of Molecular Genetics, The Ohio State University, Columbus, OH 43210
| | - Aysha H Osmani
- Department of Molecular Genetics, The Ohio State University, Columbus, OH 43210
| | - Stephen A Osmani
- Ohio State Biochemistry Program, The Ohio State University, Columbus, OH 43210 .,Department of Molecular Genetics, The Ohio State University, Columbus, OH 43210
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50
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Quinn CM, Polenova T. Structural biology of supramolecular assemblies by magic-angle spinning NMR spectroscopy. Q Rev Biophys 2017; 50:e1. [PMID: 28093096 PMCID: PMC5483179 DOI: 10.1017/s0033583516000159] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
In recent years, exciting developments in instrument technology and experimental methodology have advanced the field of magic-angle spinning (MAS) nuclear magnetic resonance (NMR) to new heights. Contemporary MAS NMR yields atomic-level insights into structure and dynamics of an astounding range of biological systems, many of which cannot be studied by other methods. With the advent of fast MAS, proton detection, and novel pulse sequences, large supramolecular assemblies, such as cytoskeletal proteins and intact viruses, are now accessible for detailed analysis. In this review, we will discuss the current MAS NMR methodologies that enable characterization of complex biomolecular systems and will present examples of applications to several classes of assemblies comprising bacterial and mammalian cytoskeleton as well as human immunodeficiency virus 1 and bacteriophage viruses. The body of work reviewed herein is representative of the recent advancements in the field, with respect to the complexity of the systems studied, the quality of the data, and the significance to the biology.
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Affiliation(s)
- Caitlin M. Quinn
- University of Delaware, Department of Chemistry and Biochemistry, Newark, DE 19711; Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, Pittsburgh, PA 15306
| | - Tatyana Polenova
- University of Delaware, Department of Chemistry and Biochemistry, Newark, DE 19711; Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, Pittsburgh, PA 15306
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