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Ghaffar A, Akhter T, Strømme P, Misceo D, Khan A, Frengen E, Umair M, Isidor B, Cogné B, Khan AA, Bruel AL, Sorlin A, Kuentz P, Chiaverini C, Innes AM, Zech M, Baláž M, Havrankova P, Jech R, Ahmed ZM, Riazuddin S, Riazuddin S. Variants of NAV3, a neuronal morphogenesis protein, cause intellectual disability, developmental delay, and microcephaly. Commun Biol 2024; 7:831. [PMID: 38977784 PMCID: PMC11231287 DOI: 10.1038/s42003-024-06466-1] [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: 01/04/2024] [Accepted: 06/18/2024] [Indexed: 07/10/2024] Open
Abstract
Microtubule associated proteins (MAPs) are widely expressed in the central nervous system, and have established roles in cell proliferation, myelination, neurite formation, axon specification, outgrowth, dendrite, and synapse formation. We report eleven individuals from seven families harboring predicted pathogenic biallelic, de novo, and heterozygous variants in the NAV3 gene, which encodes the microtubule positive tip protein neuron navigator 3 (NAV3). All affected individuals have intellectual disability (ID), microcephaly, skeletal deformities, ocular anomalies, and behavioral issues. In mouse brain, Nav3 is expressed throughout the nervous system, with more prominent signatures in postmitotic, excitatory, inhibiting, and sensory neurons. When overexpressed in HEK293T and COS7 cells, pathogenic variants impaired NAV3 ability to stabilize microtubules. Further, knocking-down nav3 in zebrafish led to severe morphological defects, microcephaly, impaired neuronal growth, and behavioral impairment, which were rescued with co-injection of WT NAV3 mRNA and not by transcripts encoding the pathogenic variants. Our findings establish the role of NAV3 in neurodevelopmental disorders, and reveal its involvement in neuronal morphogenesis, and neuromuscular responses.
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Affiliation(s)
- Amama Ghaffar
- Department of Otorhinolaryngology-Head & Neck Surgery, School of Medicine University of Maryland, Baltimore, MD, USA
- Centre of Excellence in Molecular Biology, University of the Punjab, Lahore, Pakistan
| | - Tehmeena Akhter
- Department of Otorhinolaryngology-Head & Neck Surgery, School of Medicine University of Maryland, Baltimore, MD, USA
- Centre of Excellence in Molecular Biology, University of the Punjab, Lahore, Pakistan
| | - Petter Strømme
- Division of Pediatric and Adolescent Medicine, Oslo University Hospital and University of Oslo, Oslo, Norway
| | - Doriana Misceo
- Department of Medical Genetics, Oslo University Hospital and University of Oslo, Oslo, Norway
| | - Amjad Khan
- Faculty of Biological Sciences, Department of Zoology, University of Lakki Marwat, 28420, Khyber, Pakhtunkhwa, Pakistan
- Institute for Medical Genetics and Applied Genomics, University of Tübingen, Tübinge, 72076, Germany
- Alexander von Humboldt Fellowship Foundation, Berlin, 10117, Germany
| | - Eirik Frengen
- Department of Medical Genetics, Oslo University Hospital and University of Oslo, Oslo, Norway
| | - Muhammad Umair
- Department of Life Sciences, School of Science, University of Management and Technology, Lahore, Pakistan
| | - Bertrand Isidor
- Nantes Université, CHU Nantes, Service de Génétique Médicale, 44000, Nantes, France
| | - Benjamin Cogné
- Nantes Université, CHU Nantes, Service de Génétique Médicale, 44000, Nantes, France
| | - Asma A Khan
- Centre of Excellence in Molecular Biology, University of the Punjab, Lahore, Pakistan
| | - Ange-Line Bruel
- INSERM UMR1231 GAD "Génétique des Anomalies du Développement", FHU-TRANSLAD, Université de Bourgogne Franche-Comté, Dijon, France
| | - Arthur Sorlin
- INSERM UMR1231 GAD "Génétique des Anomalies du Développement", FHU-TRANSLAD, Université de Bourgogne Franche-Comté, Dijon, France
- National Center of Genetics (NCG), Laboratoire national de santé (LNS), 1, rue Louis Rech, L-3555, Dudelange, Luxembourg
| | - Paul Kuentz
- INSERM UMR1231 GAD "Génétique des Anomalies du Développement", FHU-TRANSLAD, Université de Bourgogne Franche-Comté, Dijon, France
| | | | - A Micheil Innes
- Department of Medical Genetics, University of Calgary, Calgary, Alberta, Canada
| | - Michael Zech
- Institute of Neurogenomics, Helmholtz Munich, Neuherberg, Germany
- Institute of Human Genetics, Technical University of Munich, School of Medicine, Munich, Germany
- Institute for Advanced Study, Technical University of Munich, Lichtenbergstrasse 2 a, D-85748, Garching, Germany
| | - Marek Baláž
- First Department of Neurology, Faculty of Medicine, St. Anne's University Hospital, and CEITEC, Masaryk University, Brno, Czech Republic
| | - Petra Havrankova
- Department of Neurology, Charles University, First Faculty of Medicine and General University Hospital in Prague, Prague, Czech Republic
| | - Robert Jech
- Department of Neurology, Charles University, First Faculty of Medicine and General University Hospital in Prague, Prague, Czech Republic
| | - Zubair M Ahmed
- Department of Otorhinolaryngology-Head & Neck Surgery, School of Medicine University of Maryland, Baltimore, MD, USA
| | - Sheikh Riazuddin
- Jinnah Burn and Reconstructive Surgery Centre, Allama Iqbal Medical Research, University of Health Sciences, Lahore, Pakistan
| | - Saima Riazuddin
- Department of Otorhinolaryngology-Head & Neck Surgery, School of Medicine University of Maryland, Baltimore, MD, USA.
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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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Lawrence EJ, Chatterjee S, Zanic M. More is different: Reconstituting complexity in microtubule regulation. J Biol Chem 2023; 299:105398. [PMID: 37898404 PMCID: PMC10694663 DOI: 10.1016/j.jbc.2023.105398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2023] [Revised: 10/13/2023] [Accepted: 10/18/2023] [Indexed: 10/30/2023] Open
Abstract
Microtubules are dynamic cytoskeletal filaments that undergo stochastic switching between phases of polymerization and depolymerization-a behavior known as dynamic instability. Many important cellular processes, including cell motility, chromosome segregation, and intracellular transport, require complex spatiotemporal regulation of microtubule dynamics. This coordinated regulation is achieved through the interactions of numerous microtubule-associated proteins (MAPs) with microtubule ends and lattices. Here, we review the recent advances in our understanding of microtubule regulation, focusing on results arising from biochemical in vitro reconstitution approaches using purified multiprotein ensembles. We discuss how the combinatory effects of MAPs affect both the dynamics of individual microtubule ends, as well as the stability and turnover of the microtubule lattice. In addition, we highlight new results demonstrating the roles of protein condensates in microtubule regulation. Our overall intent is to showcase how lessons learned from reconstitution approaches help unravel the regulatory mechanisms at play in complex cellular environments.
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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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Shirai Y, Okuda T, Oshima K, Nadano D. Characterization of human Ccser2 as a protein tracking the plus-ends of microtubules. BMC Res Notes 2023; 16:198. [PMID: 37684684 PMCID: PMC10486078 DOI: 10.1186/s13104-023-06475-z] [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: 04/08/2023] [Accepted: 08/24/2023] [Indexed: 09/10/2023] Open
Abstract
OBJECTIVE Microtubules, which are closely related to cell proliferation, have been the promising therapeutic target of cancer. Therefore, it is necessary to understand the intracellular control mechanisms of microtubules, the whole picture of which is still unclear though. Intracellular dynamics of microtubules are regulated by various microtubule-associated proteins, one group of which is microtubule plus-end-tracking proteins (+ TIPs), localizing to the extending tips of microtubules. Here, we report the identification and analysis of Ccser2 as a new + TIP in human breast cancer MCF-7 cells. RESULTS Ccser2 was found to be a member of + TIPs by microscopic observations including time-lapse imaging. The C-terminal region of Ccser2, including two SxIP motifs, was likely to be important for the tracking function. In MCF-7 cells, endogenous Ccser2 was mainly detected in the peripheral regions of microtubule fibers, suggesting that Ccser2 functions in cell projections.
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Affiliation(s)
- Yuko Shirai
- Department of Applied Biosciences, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa, Nagoya, 464-8601 Japan
| | - Tomohiro Okuda
- Department of Applied Biosciences, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa, Nagoya, 464-8601 Japan
| | - Kenzi Oshima
- Department of Applied Biosciences, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa, Nagoya, 464-8601 Japan
| | - Daita Nadano
- Department of Applied Biosciences, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa, Nagoya, 464-8601 Japan
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Gcap14 is a microtubule plus-end-tracking protein coordinating microtubule-actin crosstalk during neurodevelopment. Proc Natl Acad Sci U S A 2023; 120:e2214507120. [PMID: 36795749 PMCID: PMC9974511 DOI: 10.1073/pnas.2214507120] [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] [Indexed: 02/17/2023] Open
Abstract
Regulation of microtubule dynamics is required to properly control various steps of neurodevelopment. In this study, we identified granule cell antiserum-positive 14 (Gcap14) as a microtubule plus-end-tracking protein and as a regulator of microtubule dynamics during neurodevelopment. Gcap14 knockout mice exhibited impaired cortical lamination. Gcap14 deficiency resulted in defective neuronal migration. Moreover, nuclear distribution element nudE-like 1 (Ndel1), an interacting partner of Gcap14, effectively corrected the downregulation of microtubule dynamics and the defects in neuronal migration caused by Gcap14 deficiency. Finally, we found that the Gcap14-Ndel1 complex participates in the functional link between microtubule and actin filament, thereby regulating their crosstalks in the growth cones of cortical neurons. Taken together, we propose that the Gcap14-Ndel1 complex is fundamental for cytoskeletal remodeling during neurodevelopmental processes such as neuronal processes elongation and neuronal migration.
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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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Shevchenko GV, Krutovsky KV. Mechanical stress effects on transcriptional regulation of genes encoding microtubule- and actin-associated proteins. PHYSIOLOGY AND MOLECULAR BIOLOGY OF PLANTS : AN INTERNATIONAL JOURNAL OF FUNCTIONAL PLANT BIOLOGY 2022; 28:17-30. [PMID: 35210715 PMCID: PMC8847523 DOI: 10.1007/s12298-021-01123-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 12/29/2021] [Accepted: 12/30/2021] [Indexed: 06/14/2023]
Abstract
Plant cytoskeleton regulation has been studied using a new approach based on both (1) pharmacological analysis of tubulin and actin inhibitors and (2) mechanical stimulation achieved by using a slow-rotating (2 rpm) clinostat in combination with transcriptional analysis of genes encoding TUA6, ACT2, MAP65-1, CLASP, PLDδ, FH4 and FH1 proteins in Arabidopsis thaliana seedling roots. The obtained data suggest feedback between the organization of microtubule (MT) and actin filament (AF) networks and the expression of the ACT2, TUA6, MAP65-1, CLASP and FH1/FH4 genes. Different regulation of feedback between MT/AF organization and TUA6, ACT2, MAP65-1, CLASP, FH4 and FH1 gene expression was noted during slow clinorotation, possibly due to altered mechanical impact on the cortical cytoskeleton. For the first time, the expression of the tubulin-associated gene MAP65-1 was shown to be dependent upon the organization of AFs. TUA6, MAP65-1, CLASP, FH1 and FH4 likely participate in mechanical signal transduction. Our work demonstrated that slow clinorotation is able to cause mechanical stress.
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Affiliation(s)
- Galina V. Shevchenko
- Institute of Botany, National Academy of Sciences of Ukraine, Kiev, 01004 Ukraine
| | - Konstantin V. Krutovsky
- Department of Forest Genetics and Forest Tree Breeding, Georg-August University of Göttingen, Büsgenweg 2, 37077 Göttingen, Germany
- Center for Integrated Breeding Research, Georg-August University of Göttingen, 37075 Göttingen, Germany
- Laboratory of Population Genetics, N.I. Vavilov Institute of General Genetics, Russian Academy of Sciences, 119333 Moscow, Russian Federation
- Department of Genomics and Bioinformatics, Laboratory of Forest Genomics, Genome Research and Education Center, Institute of Fundamental Biology and Biotechnology, Siberian Federal University, 660036 Krasnoyarsk, Russian Federation
- Scientific and Methodological Center, G. F. Morozov Voronezh State University of Forestry and Technologies, 394087 Voronezh, Russian Federation
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Desmin intermediate filaments and tubulin detyrosination stabilize growing microtubules in the cardiomyocyte. Basic Res Cardiol 2022; 117:53. [PMID: 36326891 PMCID: PMC9633452 DOI: 10.1007/s00395-022-00962-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 09/26/2022] [Accepted: 10/17/2022] [Indexed: 11/06/2022]
Abstract
In heart failure, an increased abundance of post-translationally detyrosinated microtubules stiffens the cardiomyocyte and impedes its contractile function. Detyrosination promotes interactions between microtubules, desmin intermediate filaments, and the sarcomere to increase cytoskeletal stiffness, yet the mechanism by which this occurs is unknown. We hypothesized that detyrosination may regulate the growth and shrinkage of dynamic microtubules to facilitate interactions with desmin and the sarcomere. Through a combination of biochemical assays and direct observation of growing microtubule plus-ends in adult cardiomyocytes, we find that desmin is required to stabilize growing microtubules at the level of the sarcomere Z-disk, where desmin also rescues shrinking microtubules from continued depolymerization. Further, reducing detyrosination (i.e. tyrosination) below basal levels promotes frequent depolymerization and less efficient growth of microtubules. This is concomitant with tyrosination promoting the interaction of microtubules with the depolymerizing protein complex of end-binding protein 1 (EB1) and CAP-Gly domain-containing linker protein 1 (CLIP1/CLIP170). The dynamic growth and shrinkage of tyrosinated microtubules reduce their opportunity for stabilizing interactions at the Z-disk region, coincident with tyrosination globally reducing microtubule stability. These data provide a model for how intermediate filaments and tubulin detyrosination establish long-lived and physically reinforced microtubules that stiffen the cardiomyocyte and inform both the mechanism of action and therapeutic index for strategies aimed at restoring tyrosination for the treatment of cardiac disease.
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Wordeman L, Vicente JJ. Microtubule Targeting Agents in Disease: Classic Drugs, Novel Roles. Cancers (Basel) 2021; 13:cancers13225650. [PMID: 34830812 PMCID: PMC8616087 DOI: 10.3390/cancers13225650] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Revised: 11/09/2021] [Accepted: 11/10/2021] [Indexed: 12/12/2022] Open
Abstract
Microtubule-targeting agents (MTAs) represent one of the most successful first-line therapies prescribed for cancer treatment. They interfere with microtubule (MT) dynamics by either stabilizing or destabilizing MTs, and in culture, they are believed to kill cells via apoptosis after eliciting mitotic arrest, among other mechanisms. This classical view of MTA therapies persisted for many years. However, the limited success of drugs specifically targeting mitotic proteins, and the slow growing rate of most human tumors forces a reevaluation of the mechanism of action of MTAs. Studies from the last decade suggest that the killing efficiency of MTAs arises from a combination of interphase and mitotic effects. Moreover, MTs have also been implicated in other therapeutically relevant activities, such as decreasing angiogenesis, blocking cell migration, reducing metastasis, and activating innate immunity to promote proinflammatory responses. Two key problems associated with MTA therapy are acquired drug resistance and systemic toxicity. Accordingly, novel and effective MTAs are being designed with an eye toward reducing toxicity without compromising efficacy or promoting resistance. Here, we will review the mechanism of action of MTAs, the signaling pathways they affect, their impact on cancer and other illnesses, and the promising new therapeutic applications of these classic drugs.
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Chia S, Leung T, Tan I. Cyclical phosphorylation of LRAP35a and CLASP2 by GSK3β and CK1δ regulates EB1-dependent MT dynamics in cell migration. Cell Rep 2021; 36:109687. [PMID: 34525355 DOI: 10.1016/j.celrep.2021.109687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 07/02/2021] [Accepted: 08/19/2021] [Indexed: 11/30/2022] Open
Abstract
Mammalian cell cytoskeletal reorganization for efficient directional movement requires tight coordination of actomyosin and microtubule networks. In this study, we show that LRAP35a potentiates microtubule stabilization by promoting CLASP2/EB1 interaction besides its complex formation with MRCK/MYO18A for retrograde actin flow. The alternate regulation of these two networks by LRAP35a is tightly regulated by a series of phosphorylation events that dictated its specificity. Sequential phosphorylation of LRAP35a by Protein Kinase A (PKA) and Glycogen Synthase Kinase-3β (GSK3β) initiates the association of LRAP35a with CLASP2, while subsequent binding and further phosphorylation by Casein Kinase 1δ (CK1δ) induce their dissociation, which facilitates LRAP35a/MRCK association in driving lamellar actomyosin flow. Importantly, microtubule dynamics is directly moderated by CK1δ activity on CLASP2 to regulate GSK3β phosphorylation of the SxIP motifs that blocks EB1 binding, an event countered by LRAP35a interaction and its competition for CK1δ activity. Overall this study reveals an essential role for LRAP35a in coordinating lamellar contractility and microtubule polarization in cell migration.
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Affiliation(s)
- Shumei Chia
- Institute of Molecular and Cell Biology, A(∗)STAR, 61 Biopolis Drive, Proteos, Singapore 138673, Singapore; Genome Institute of Singapore, A(∗)STAR, 60 Biopolis Street, #02-01 Genome, Singapore 138672, Singapore; Department of Anatomy, Yong Loo Lin School of Medicine, MD10, 4 Medical Drive, Singapore 117594, Singapore.
| | - Thomas Leung
- Institute of Molecular and Cell Biology, A(∗)STAR, 61 Biopolis Drive, Proteos, Singapore 138673, Singapore; Department of Anatomy, Yong Loo Lin School of Medicine, MD10, 4 Medical Drive, Singapore 117594, Singapore
| | - Ivan Tan
- Institute of Molecular and Cell Biology, A(∗)STAR, 61 Biopolis Drive, Proteos, Singapore 138673, Singapore; Bioprocessing Technology Institute, A(∗)STAR, 20 Biopolis Way, #06-01, Centros, Singapore 138668, Singapore.
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Predicted Cellular Interactors of the Endogenous Retrovirus-K Integrase Enzyme. Microorganisms 2021; 9:microorganisms9071509. [PMID: 34361946 PMCID: PMC8303831 DOI: 10.3390/microorganisms9071509] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 07/06/2021] [Accepted: 07/09/2021] [Indexed: 12/18/2022] Open
Abstract
Integrase (IN) enzymes are found in all retroviruses and are crucial in the retroviral integration process. Many studies have revealed how exogenous IN enzymes, such as the human immunodeficiency virus (HIV) IN, contribute to altered cellular function. However, the same consideration has not been given to viral IN originating from symbionts within our own DNA. Endogenous retrovirus-K (ERVK) is pathologically associated with neurological and inflammatory diseases along with several cancers. The ERVK IN interactome is unknown, and the question of how conserved the ERVK IN protein-protein interaction motifs are as compared to other retroviral integrases is addressed in this paper. The ERVK IN protein sequence was analyzed using the Eukaryotic Linear Motif (ELM) database, and the results are compared to ELMs of other betaretroviral INs and similar eukaryotic INs. A list of putative ERVK IN cellular protein interactors was curated from the ELM list and submitted for STRING analysis to generate an ERVK IN interactome. KEGG analysis was used to identify key pathways potentially influenced by ERVK IN. It was determined that the ERVK IN potentially interacts with cellular proteins involved in the DNA damage response (DDR), cell cycle, immunity, inflammation, cell signaling, selective autophagy, and intracellular trafficking. The most prominent pathway identified was viral carcinogenesis, in addition to select cancers, neurological diseases, and diabetic complications. This potentiates the role of ERVK IN in these pathologies via protein-protein interactions facilitating alterations in key disease pathways.
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EB2 promotes hepatocellular carcinoma proliferation and metastasis via MAPK/ERK pathway by modulating microtubule dynamics. Clin Sci (Lond) 2021; 135:847-864. [PMID: 33755094 DOI: 10.1042/cs20201500] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 03/09/2021] [Accepted: 03/23/2021] [Indexed: 01/22/2023]
Abstract
Metastasis is the main cause of poor postoperative survival of hepatocellular carcinoma (HCC) patients. Cytoskeleton rearrangement is a key event in cancer metastasis. However, the significance of microtubule (MT), one of the core components of cytoskeleton, in this process is only beginning to be revealed. Here, we find that the MT dynamics regulator end-binding protein 2 (EB2) is highly expressed in HCC and predicts poor prognosis of HCC patients. Functional studies show that EB2 overexpression promotes HCC proliferation, invasion and metastasis in vitro and in vivo, while EB2 knockdown has opposite results. Mechanistically, EB2 mediates MTs destabilization, increases Src (Src proto-oncogene non-receptor tyrosine kinase) activity, and thus facilitates extracellular signal-regulated kinase (ERK) signaling activation, which could in turn promote EB2 expression in HCC, eventually resulting in enhanced HCC proliferation, invasion and metastasis. Furthermore, U0126, a specific ERK inhibitor, could effectively inhibit EB2-mediated HCC proliferation and metastasis in vitro and in vivo. In conclusion, EB2 coordinates MT cytoskeleton and intracellular signal transduction, forming an EB2-MT-ERK positive feedback loop, to facilitate HCC proliferation, invasion and metastasis. EB2 could serve as a promising prognostic biomarker and potential therapeutic target for HCC; HCC patients with high EB2 expression may benefit from treatment with ERK inhibitors.
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Zhou D, Nie ZW, Cui XS. EB1 Is Essential for Spindle Formation and Chromosome Alignment During Oocyte Meiotic Maturation in Mice. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2021; 27:385-391. [PMID: 33413706 DOI: 10.1017/s1431927620024897] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The cytoskeleton plays an orchestrating role in polarized cell growth. Microtubules (MTs) not only play critical roles in chromosome alignment and segregation but also control cell shape, division, and motility. A member of the plus-end tracking proteins, end-binding protein 1 (EB1), regulates MT dynamics and plays vital roles in maintaining spindle symmetry and chromosome alignment during mitosis. However, the role of EB1 in mouse oocyte meiosis remains unknown. Here, we examined the localization patterns and expression levels of EB1 at different stages. EB1 protein level was found to be stable during meiosis. EB1 mainly localized along the spindle and had a similar localization pattern as that of α-tubulin. The EB1 protein was degraded with a Trim-Away method, and the results were further confirmed with western blotting and immunofluorescence. At 12 h of culture after EB1 knockdown (KD), a reduced number of mature MII oocytes were observed. EB1 KD led to spindle disorganization, chromosome misalignment, and missegregation; β-catenin protein binds to actin via the adherens junctional complex, which was significantly reduced in the EB1 KD oocytes. Collectively, we propose that the impairment of EB1 function manipulates spindle formation, thereby promoting chromosomal loss, which is expected to fuel aneuploidy and possibly fertilization failure.
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Affiliation(s)
- Dongjie Zhou
- Department of Animal Science, Chungbuk National University, 356 Room, S21-5 Dong, Chungdae-ro 1, Seowon-Gu, Cheongju, Chungbuk28644, South Korea
| | - Zheng-Wen Nie
- Department of Animal Science, Chungbuk National University, 356 Room, S21-5 Dong, Chungdae-ro 1, Seowon-Gu, Cheongju, Chungbuk28644, South Korea
| | - Xiang-Shun Cui
- Department of Animal Science, Chungbuk National University, 356 Room, S21-5 Dong, Chungdae-ro 1, Seowon-Gu, Cheongju, Chungbuk28644, South Korea
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14
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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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15
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Chanez B, Ostacolo K, Badache A, Thuault S. EB1 Restricts Breast Cancer Cell Invadopodia Formation and Matrix Proteolysis via FAK. Cells 2021; 10:cells10020388. [PMID: 33668531 PMCID: PMC7918453 DOI: 10.3390/cells10020388] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 02/09/2021] [Accepted: 02/10/2021] [Indexed: 01/07/2023] Open
Abstract
Regulation of microtubule dynamics by plus-end tracking proteins (+TIPs) plays an essential role in cancer cell migration. However, the role of +TIPs in cancer cell invasion has been poorly addressed. Invadopodia, actin-rich protrusions specialized in extracellular matrix degradation, are essential for cancer cell invasion and metastasis, the leading cause of death in breast cancer. We, therefore, investigated the role of the End Binding protein, EB1, a major hub of the +TIP network, in invadopodia functions. EB1 silencing increased matrix degradation by breast cancer cells. This was recapitulated by depletion of two additional +TIPs and EB1 partners, APC and ACF7, but not by the knockdown of other +TIPs, such as CLASP1/2 or CLIP170. The knockdown of Focal Adhesion Kinase (FAK) was previously proposed to similarly promote invadopodia formation as a consequence of a switch of the Src kinase from focal adhesions to invadopodia. Interestingly, EB1-, APC-, or ACF7-depleted cells had decreased expression/activation of FAK. Remarkably, overexpression of wild type FAK, but not of FAK mutated to prevent Src recruitment, prevented the increased degradative activity induced by EB1 depletion. Overall, we propose that EB1 restricts invadopodia formation through the control of FAK and, consequently, the spatial regulation of Src activity.
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Affiliation(s)
| | | | - Ali Badache
- Correspondence: (A.B.); (S.T.); Tel.: +33-(0)4-8697-7352 (S.T.)
| | - Sylvie Thuault
- Correspondence: (A.B.); (S.T.); Tel.: +33-(0)4-8697-7352 (S.T.)
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16
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Castle BT, McKibben KM, Rhoades E, Odde DJ. Tau Avoids the GTP Cap at Growing Microtubule Plus-Ends. iScience 2020; 23:101782. [PMID: 33294790 PMCID: PMC7691178 DOI: 10.1016/j.isci.2020.101782] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 09/15/2020] [Accepted: 11/04/2020] [Indexed: 10/26/2022] Open
Abstract
Plus-end tracking proteins (+TIPs) associate with the growing end of microtubules and mediate important cellular functions. The majority of +TIPs are directed to the plus-end through a family of end-binding proteins (EBs), which preferentially bind the stabilizing cap of GTP-tubulin present during microtubule growth. One outstanding question is whether there may exist other microtubule-associated proteins (MAPs) that preferentially bind specific nucleotide states of tubulin. Here, we report that the neuronal MAP tau preferentially binds GDP-tubulin (K D = 0.26 μM) over GMPCPP-tubulin (K D = 1.1 μM) in vitro, as well as GTP-tubulin at the tips of growing microtubules, causing tau binding to lag behind the plus-end both in vitro and in live cells. Thus, tau is a microtubule tip avoiding protein, establishing the framework for a possible new class of tip avoiding MAPs. We speculate that disease-relevant tau mutations may exert their phenotype by their failure to properly recognize GDP-tubulin.
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Affiliation(s)
- Brian T. Castle
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN 55455, USA
| | - Kristen M. McKibben
- Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Elizabeth Rhoades
- Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - David J. Odde
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN 55455, USA
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17
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Much More Than a Scaffold: Cytoskeletal Proteins in Neurological Disorders. Cells 2020; 9:cells9020358. [PMID: 32033020 PMCID: PMC7072452 DOI: 10.3390/cells9020358] [Citation(s) in RCA: 63] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 01/27/2020] [Accepted: 01/29/2020] [Indexed: 02/08/2023] Open
Abstract
Recent observations related to the structure of the cytoskeleton in neurons and novel cytoskeletal abnormalities involved in the pathophysiology of some neurological diseases are changing our view on the function of the cytoskeletal proteins in the nervous system. These efforts allow a better understanding of the molecular mechanisms underlying neurological diseases and allow us to see beyond our current knowledge for the development of new treatments. The neuronal cytoskeleton can be described as an organelle formed by the three-dimensional lattice of the three main families of filaments: actin filaments, microtubules, and neurofilaments. This organelle organizes well-defined structures within neurons (cell bodies and axons), which allow their proper development and function through life. Here, we will provide an overview of both the basic and novel concepts related to those cytoskeletal proteins, which are emerging as potential targets in the study of the pathophysiological mechanisms underlying neurological disorders.
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18
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Cui YJ, Ma CC, Zhang CM, Tang LQ, Liu ZP. The discovery of novel indazole derivatives as tubulin colchicine site binding agents that displayed potent antitumor activity both in vitro and in vivo. Eur J Med Chem 2020; 187:111968. [DOI: 10.1016/j.ejmech.2019.111968] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 11/25/2019] [Accepted: 12/11/2019] [Indexed: 02/06/2023]
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Abstract
Light can be controlled with high spatial and temporal accuracy. Therefore, optogenetics is an attractive experimental approach to modulate intracellular cytoskeleton dynamics at much faster timescales than by genetic modification. For example, in mammalian cells, microtubules (MTs) grow tens of micrometers per minute and many intracellular MT functions are mediated by a complex of +TIP proteins that dynamically associate with growing MT plus ends. EB1 is a central component of this +TIP protein network, and we recently developed a photo-inactivated π-EB1 by inserting a blue light-sensitive LOV2/Zdk1 module between the EB1 MT-binding domain and the +TIP adaptor domain. Blue light-induced π-EB1 photodissociation results in disassembly of the +TIP complex and strongly attenuates MT growth in mammalian cells.In this chapter, we discuss theoretical and practical aspects of how to perform high-resolution live-cell microscopy in combination with π-EB1 photodissociation. However, these techniques are broadly applicable to other LOV2-based and likely other blue light-sensitive optogenetics. In addition to being a tool to investigate +TIP functions acutely and with subcellular resolution, because of its dramatic and rapid change in intracellular localization, π-EB1 can serve as a powerful tool to test and characterize optogenetic illumination setups. We describe protocols on how to achieve micrometer-scale intracellular control of π-EB1 activity using patterned illumination, and we introduce a do-it-yourself LED cube design compatible with transmitted light microscopy in multiwell plates.
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Affiliation(s)
- Jeffrey van Haren
- Department of Cell and Tissue Biology, University of California San Francisco, San Francisco, CA, USA.,Department of Cell Biology, Erasmus MC, Rotterdam, The Netherlands
| | - Lauren S Adachi
- Department of Cell and Tissue Biology, University of California San Francisco, San Francisco, CA, USA
| | - Torsten Wittmann
- Department of Cell and Tissue Biology, University of California San Francisco, San Francisco, CA, USA.
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20
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Niu X, Zheng F, Fu C. The concerted actions of Tip1/CLIP-170, Klp5/Kinesin-8, and Alp14/XMAP215 regulate microtubule catastrophe at the cell end. J Mol Cell Biol 2019; 11:956-966. [PMID: 31071203 PMCID: PMC6927233 DOI: 10.1093/jmcb/mjz039] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 03/23/2019] [Accepted: 04/26/2019] [Indexed: 11/14/2022] Open
Abstract
Spatial regulation of microtubule catastrophe is important for controlling microtubule length and consequently contributes to the proper establishment of cell polarity and cell growth. The +TIP proteins including Tip1/CLIP-170, Klp5/Kinesin-8, and Alp14/XMAP215 reside at microtubule plus ends to regulate microtubule dynamics. In the fission yeast Schizosaccharomyces pombe, Tip1 and Alp14 serve as microtubule-stabilizing factors, while Klp5 functions oppositely as a catastrophe-promoting factor. Despite that Tip1 has been shown to play a key role in restricting microtubule catastrophe to the cell end, how Tip1 fulfills the role remains to be determined. Employing live-cell microscopy, we showed that the absence of Tip1 impairs the localization of both Klp5 and Alp14 at microtubule plus ends, but the absence of Klp5 prolongs the residence time of Tip1 at microtubule plus ends. We further revealed that Klp5 accumulates behind Tip1 at microtubule plus ends in a Tip1-dependent manner. In addition, artificially tethering Klp5 to microtubule plus ends promotes premature microtubule catastrophe, while tethering Alp14 to microtubule plus ends in the cells lacking Tip1 rescues the phenotype of short microtubules. These findings establish that Tip1 restricts microtubule catastrophe to the cell end likely by spatially restricting the microtubule catastrophe activity of Klp5 and stabilizing Alp14 at microtubule plus ends. Thus, the work demonstrates the orchestration of Tip1, Alp14, and Klp5 in ensuring microtubule catastrophe at the cell end.
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Affiliation(s)
- Xiaojia Niu
- Division of Molecular & Cell Biophysics, Hefei National Science Center for Physical Sciences, University of Science and Technology of China, Hefei, Anhui, China.,Chinese Academy of Sciences Center for Excellence in Molecular Cell Sciences, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, China.,Anhui Key Laboratory for Cellular Dynamics & Chemical Biology, University of Science and Technology of China, Hefei, China
| | - Fan Zheng
- Division of Molecular & Cell Biophysics, Hefei National Science Center for Physical Sciences, University of Science and Technology of China, Hefei, Anhui, China.,Chinese Academy of Sciences Center for Excellence in Molecular Cell Sciences, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, China.,Anhui Key Laboratory for Cellular Dynamics & Chemical Biology, University of Science and Technology of China, Hefei, China
| | - Chuanhai Fu
- Division of Molecular & Cell Biophysics, Hefei National Science Center for Physical Sciences, University of Science and Technology of China, Hefei, Anhui, China.,Chinese Academy of Sciences Center for Excellence in Molecular Cell Sciences, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, China.,Anhui Key Laboratory for Cellular Dynamics & Chemical Biology, University of Science and Technology of China, Hefei, China
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21
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Parker SS, Krantz J, Kwak EA, Barker NK, Deer CG, Lee NY, Mouneimne G, Langlais PR. Insulin Induces Microtubule Stabilization and Regulates the Microtubule Plus-end Tracking Protein Network in Adipocytes. Mol Cell Proteomics 2019; 18:1363-1381. [PMID: 31018989 PMCID: PMC6601206 DOI: 10.1074/mcp.ra119.001450] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Indexed: 12/21/2022] Open
Abstract
Insulin-stimulated glucose uptake is known to involve microtubules, although the function of microtubules and the microtubule-regulating proteins involved in insulin action are poorly understood. CLASP2, a plus-end tracking microtubule-associated protein (+TIP) that controls microtubule dynamics, was recently implicated as the first +TIP associated with insulin-regulated glucose uptake. Here, using protein-specific targeted quantitative phosphoproteomics within 3T3-L1 adipocytes, we discovered that insulin regulates phosphorylation of the CLASP2 network members G2L1, MARK2, CLIP2, AGAP3, and CKAP5 as well as EB1, revealing the existence of a previously unknown microtubule-associated protein system that responds to insulin. To further investigate, G2L1 interactome studies within 3T3-L1 adipocytes revealed that G2L1 coimmunoprecipitates CLASP2 and CLIP2 as well as the master integrators of +TIP assembly, the end binding (EB) proteins. Live-cell total internal reflection fluorescence microscopy in adipocytes revealed G2L1 and CLASP2 colocalize on microtubule plus-ends. We found that although insulin increases the number of CLASP2-containing plus-ends, insulin treatment simultaneously decreases CLASP2-containing plus-end velocity. In addition, we discovered that insulin stimulates redistribution of CLASP2 and G2L1 from exclusive plus-end tracking to "trailing" behind the growing tip of the microtubule. Insulin treatment increases α-tubulin Lysine 40 acetylation, a mechanism that was observed to be regulated by a counterbalance between GSK3 and mTOR, and led to microtubule stabilization. Our studies introduce insulin-stimulated microtubule stabilization and plus-end trailing of +TIPs as new modes of insulin action and reveal the likelihood that a network of microtubule-associated proteins synergize to coordinate insulin-regulated microtubule dynamics.
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Affiliation(s)
- Sara S Parker
- From the ‡Department of Cellular & Molecular Medicine
| | - James Krantz
- §Department of Medicine, Division of Endocrinology
| | | | | | - Chris G Deer
- University of Arizona Research Computing, University of Arizona, Tucson, Arizona 85721
| | - Nam Y Lee
- ¶Department of Pharmacology,; ‖Department of Chemistry & Biochemistry, University of Arizona College of Medicine, Tucson, Arizona 85721
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22
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Blanco C, Morales D, Mogollones I, Vergara‐Jaque A, Vargas C, Álvarez A, Riquelme D, Leiva‐Salcedo E, González W, Morales D, Maureira D, Aldunate I, Cáceres M, Varela D, Cerda O. EB1‐ and EB2‐dependent anterograde trafficking of TRPM4 regulates focal adhesion turnover and cell invasion. FASEB J 2019; 33:9434-9452. [DOI: 10.1096/fj.201900136r] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Constanza Blanco
- Program of Cellular and Molecular Biology Universidad de Chile Santiago Chile
- Millennium Nucleus of Ion Channels‐Associated Diseases (MiNICAD) Santiago Chile
| | - Danna Morales
- Program of Physiology and Biophysics Institute of Biomedical Sciences Faculty of Medicine Universidad de Chile Santiago Chile
- Millennium Nucleus of Ion Channels‐Associated Diseases (MiNICAD) Santiago Chile
| | - Ignacio Mogollones
- Program of Cellular and Molecular Biology Universidad de Chile Santiago Chile
- Millennium Nucleus of Ion Channels‐Associated Diseases (MiNICAD) Santiago Chile
| | - Ariela Vergara‐Jaque
- Program of Physiology and Biophysics Institute of Biomedical Sciences Faculty of Medicine Universidad de Chile Santiago Chile
- Multidisciplinary Scientific Nucleus Universidad de Talca Talca Chile
- Center for Bioinformatics and Molecular Simulation Universidad de Talca Talca Chile
| | - Carla Vargas
- Program of Cellular and Molecular Biology Universidad de Chile Santiago Chile
- Millennium Nucleus of Ion Channels‐Associated Diseases (MiNICAD) Santiago Chile
| | - Alhejandra Álvarez
- Program of Cellular and Molecular Biology Universidad de Chile Santiago Chile
- Millennium Nucleus of Ion Channels‐Associated Diseases (MiNICAD) Santiago Chile
| | - Denise Riquelme
- Department of Biology Faculty of Chemistry and Biology Universidad de Santiago de Chile Santiago Chile
| | - Elías Leiva‐Salcedo
- Department of Biology Faculty of Chemistry and Biology Universidad de Santiago de Chile Santiago Chile
| | - Wendy González
- Millennium Nucleus of Ion Channels‐Associated Diseases (MiNICAD) Santiago Chile
- Center for Bioinformatics and Molecular Simulation Universidad de Talca Talca Chile
| | - Diego Morales
- Program of Cellular and Molecular Biology Universidad de Chile Santiago Chile
- Millennium Nucleus of Ion Channels‐Associated Diseases (MiNICAD) Santiago Chile
| | - Diego Maureira
- Program of Cellular and Molecular Biology Universidad de Chile Santiago Chile
- Millennium Nucleus of Ion Channels‐Associated Diseases (MiNICAD) Santiago Chile
| | - Ismael Aldunate
- Program of Cellular and Molecular Biology Universidad de Chile Santiago Chile
| | - Mónica Cáceres
- Program of Cellular and Molecular Biology Universidad de Chile Santiago Chile
- Millennium Nucleus of Ion Channels‐Associated Diseases (MiNICAD) Santiago Chile
- The Wound Repair Treatment, and Health (WoRTH) Initiative Santiago Chile
| | - Diego Varela
- Program of Physiology and Biophysics Institute of Biomedical Sciences Faculty of Medicine Universidad de Chile Santiago Chile
- Millennium Nucleus of Ion Channels‐Associated Diseases (MiNICAD) Santiago Chile
| | - Oscar Cerda
- Program of Cellular and Molecular Biology Universidad de Chile Santiago Chile
- Millennium Nucleus of Ion Channels‐Associated Diseases (MiNICAD) Santiago Chile
- The Wound Repair Treatment, and Health (WoRTH) Initiative Santiago Chile
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23
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van Haren J, Wittmann T. Microtubule Plus End Dynamics - Do We Know How Microtubules Grow?: Cells boost microtubule growth by promoting distinct structural transitions at growing microtubule ends. Bioessays 2019; 41:e1800194. [PMID: 30730055 PMCID: PMC7021488 DOI: 10.1002/bies.201800194] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 12/22/2018] [Indexed: 12/31/2022]
Abstract
Microtubules form a highly dynamic filament network in all eukaryotic cells. Individual microtubules grow by tubulin dimer subunit addition and frequently switch between phases of growth and shortening. These unique dynamics are powered by GTP hydrolysis and drive microtubule network remodeling, which is central to eukaryotic cell biology and morphogenesis. Yet, our knowledge of the molecular events at growing microtubule ends remains incomplete. Here, recent ultrastructural, biochemical and cell biological data are integrated to develop a realistic model of growing microtubule ends comprised of structurally distinct but biochemically overlapping zones. Proteins that recognize microtubule lattice conformations associated with specific tubulin guanosine nucleotide states may independently control major structural transitions at growing microtubule ends. A model is proposed in which tubulin dimer addition and subsequent closure of the MT wall are optimized in cells to achieve rapid physiological microtubule growth.
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Affiliation(s)
- Jeffrey van Haren
- Department of Cell and Tissue Biology, University of California San Francisco, 513 Parnassus Avenue, San Francisco, CA, 94143, USA
| | - Torsten Wittmann
- Department of Cell and Tissue Biology, University of California San Francisco, 513 Parnassus Avenue, San Francisco, CA, 94143, USA
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24
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Deretic J, Kerr A, Welburn JPI. A rapid computational approach identifies SPICE1 as an Aurora kinase substrate. Mol Biol Cell 2019; 30:312-323. [PMID: 30485161 PMCID: PMC6589576 DOI: 10.1091/mbc.e18-08-0495] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 11/08/2018] [Accepted: 11/20/2018] [Indexed: 11/11/2022] Open
Abstract
Aurora kinases play a major role in mitosis by regulating diverse substrates. Defining their critical downstream targets is important in understanding Aurora kinase function. Here we have developed an unbiased computational approach to identify new Aurora kinase substrates based on phosphorylation site clustering, protein localization, protein structure, and species conservation. We validate the microtubule-associated proteins Clasp2, Elys, tubulin tyrosine ligase-like polyglutamylase residues 330-624 and spindle and centriole associated protein 1, residues 549-855 (SPICE1), as Aurora A and B kinases substrates in vitro. We also demonstrate that SPICE1 localization is regulated by Aurora kinases during mitosis. In the absence of Aurora kinase activity, SPICE1 remains at centrioles but does not target to the spindle. Similarly, a nonphosphorylatable SPICE1 mutant no longer localizes to the spindle. Finally, we show that misregulating SPICE1 phosphorylation results in abnormal centriole number, spindle multipolarity, and chromosome alignment defects. Overall, our work indicates that temporal and spatial Aurora kinase-mediated regulation of SPICE1 is important for correct chromosome segregation. In addition, our work provides a database-search tool that enables rapid identification of Aurora kinase substrates.
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Affiliation(s)
- Jovana Deretic
- Wellcome Trust Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3JR, Scotland, UK
| | - Alastair Kerr
- Wellcome Trust Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3JR, Scotland, UK
| | - Julie P. I. Welburn
- Wellcome Trust Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3JR, Scotland, UK
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25
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The Tubulin Detyrosination Cycle: Function and Enzymes. Trends Cell Biol 2019; 29:80-92. [DOI: 10.1016/j.tcb.2018.08.003] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 08/14/2018] [Accepted: 08/15/2018] [Indexed: 12/24/2022]
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26
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LaFlamme SE, Mathew-Steiner S, Singh N, Colello-Borges D, Nieves B. Integrin and microtubule crosstalk in the regulation of cellular processes. Cell Mol Life Sci 2018; 75:4177-4185. [PMID: 30206641 PMCID: PMC6182340 DOI: 10.1007/s00018-018-2913-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2018] [Revised: 08/14/2018] [Accepted: 08/27/2018] [Indexed: 11/25/2022]
Abstract
Integrins engage components of the extracellular matrix, and in collaboration with other receptors, regulate signaling cascades that impact cell behavior in part by modulating the cell's cytoskeleton. Integrins have long been known to function together with the actin cytoskeleton to promote cell adhesion, migration, and invasion, and with the intermediate filament cytoskeleton to mediate the strong adhesion needed for the maintenance and integrity of epithelial tissues. Recent studies have shed light on the crosstalk between integrin and the microtubule cytoskeleton. Integrins promote microtubule nucleation, growth, and stabilization at the cell cortex, whereas microtubules regulate integrin activity and remodeling of adhesion sites. Integrin-dependent stabilization of microtubules at the cell cortex is critical to the establishment of apical-basal polarity required for the formation of epithelial tissues. During cell migration, integrin-dependent microtubule stabilization contributes to front-rear polarity, whereas microtubules promote the turnover of integrin-mediated adhesions. This review focuses on this interdependent relationship and its impact on cell behavior and function.
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Affiliation(s)
- Susan E LaFlamme
- Department of Regenerative and Cancer Cell Biology, Albany Medical College, 47 New Scotland Avenue, Albany, NY, 12208, USA.
| | - Shomita Mathew-Steiner
- Department of Regenerative and Cancer Cell Biology, Albany Medical College, 47 New Scotland Avenue, Albany, NY, 12208, USA
- Indiana University, 975 W. Walnut Street, Indianapolis, IN, 46202, USA
| | - Neetu Singh
- Department of Regenerative and Cancer Cell Biology, Albany Medical College, 47 New Scotland Avenue, Albany, NY, 12208, USA
| | - Diane Colello-Borges
- Department of Regenerative and Cancer Cell Biology, Albany Medical College, 47 New Scotland Avenue, Albany, NY, 12208, USA
| | - Bethsaida Nieves
- Department of Regenerative and Cancer Cell Biology, Albany Medical College, 47 New Scotland Avenue, Albany, NY, 12208, USA
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27
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Combinatorial expression of microtubule-associated EB1 and ATIP3 biomarkers improves breast cancer prognosis. Breast Cancer Res Treat 2018; 173:573-583. [PMID: 30368744 DOI: 10.1007/s10549-018-5026-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2018] [Accepted: 10/21/2018] [Indexed: 01/13/2023]
Abstract
PURPOSE The identification of molecular biomarkers for classification of breast cancer is needed to better stratify the patients and guide therapeutic decisions. The aim of this study was to investigate the value of MAPRE1 gene encoding microtubule-end binding proteins EB1 as a biomarker in breast cancer and evaluate whether combinatorial expression of MAPRE1 and MTUS1 gene encoding EB1-negative regulator ATIP3 may improve breast cancer diagnosis and prognosis. METHODS Probeset intensities for MAPRE1 and MTUS1 genes were retrieved from Exonhit splice array analyses of 45 benign and 120 malignant breast tumors for diagnostic purposes. Transcriptomic analyses (U133 Affymetrix array) of one exploratory cohort of 150 invasive breast cancer patients and two independent series of 130 and 155 samples were compared with clinical data of the patients for prognostic studies. A tissue microarray from an independent cohort of 212 invasive breast tumors was immunostained with anti-EB1 and anti-ATIP3 antibodies. RESULTS We show that MAPRE1 gene is a diagnostic and prognostic biomarker in breast cancer. High MAPRE1 levels correlate with tumor malignancy, high histological grade and poor clinical outcome. Combination of high-MAPRE1 and low-MTUS1 levels in tumors is significantly associated with tumor aggressiveness and reduced patient survival. IHC studies of combined EB1/ATIP3 protein expression confirmed these results. CONCLUSIONS These studies emphasize the importance of studying combinatorial expression of EB1 and ATIP3 genes and proteins rather than each biomarker alone. A population of highly aggressive breast tumors expressing high-EB1/low-ATIP3 may be considered for the development of new molecular therapies.
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28
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Monda JK, Cheeseman IM. The kinetochore-microtubule interface at a glance. J Cell Sci 2018; 131:131/16/jcs214577. [PMID: 30115751 DOI: 10.1242/jcs.214577] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Accurate chromosome segregation critically depends on the formation of attachments between microtubule polymers and each sister chromatid. The kinetochore is the macromolecular complex that assembles at the centromere of each chromosome during mitosis and serves as the link between the DNA and the microtubules. In this Cell Science at a Glance article and accompanying poster, we discuss the activities and molecular players that are involved in generating kinetochore-microtubule attachments, including the initial stages of lateral kinetochore-microtubule interactions and maturation to stabilized end-on attachments. We additionally explore the features that contribute to the ability of the kinetochore to track with dynamic microtubules. Finally, we examine the contributions of microtubule-associated proteins to the organization and stabilization of the mitotic spindle and the control of microtubule dynamics.
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Affiliation(s)
- Julie K Monda
- Whitehead Institute for Biomedical Research, 455 Main Street, Cambridge, MA 02142, USA.,Department of Biology, MIT, Cambridge, MA 02142, USA
| | - Iain M Cheeseman
- Whitehead Institute for Biomedical Research, 455 Main Street, Cambridge, MA 02142, USA .,Department of Biology, MIT, Cambridge, MA 02142, USA
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29
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Kahn OI, Schätzle P, van de Willige D, Tas RP, Lindhout FW, Portegies S, Kapitein LC, Hoogenraad CC. APC2 controls dendrite development by promoting microtubule dynamics. Nat Commun 2018; 9:2773. [PMID: 30018294 PMCID: PMC6050278 DOI: 10.1038/s41467-018-05124-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Accepted: 06/12/2018] [Indexed: 12/12/2022] Open
Abstract
Mixed polarity microtubule organization is the signature characteristic of vertebrate dendrites. Oppositely oriented microtubules form the basis for selective cargo trafficking in neurons, however the mechanisms that establish and maintain this organization are unclear. Here, we show that APC2, the brain-specific homolog of tumor-suppressor protein adenomatous polyposis coli (APC), promotes dynamics of minus-end-out microtubules in dendrites. We found that APC2 localizes as distinct clusters along microtubule bundles in dendrites and that this localization is driven by LC8-binding and two separate microtubule-interacting domains. Depletion of APC2 reduces the plus end dynamics of minus-end-out oriented microtubules, increases microtubule sliding, and causes defects in dendritic morphology. We propose a model in which APC2 regulates dendrite development by promoting dynamics of minus-end-out microtubules.
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Affiliation(s)
- Olga I Kahn
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, 3584 CH, Utrecht, The Netherlands
| | - Philipp Schätzle
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, 3584 CH, Utrecht, The Netherlands
| | - Dieudonnée van de Willige
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, 3584 CH, Utrecht, The Netherlands
| | - Roderick P Tas
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, 3584 CH, Utrecht, The Netherlands
| | - Feline W Lindhout
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, 3584 CH, Utrecht, The Netherlands
| | - Sybren Portegies
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, 3584 CH, Utrecht, The Netherlands
| | - Lukas C Kapitein
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, 3584 CH, Utrecht, The Netherlands
| | - Casper C Hoogenraad
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, 3584 CH, Utrecht, The Netherlands.
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30
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Ma G, Zhang Q, He L, Nguyen NT, Liu S, Gong Z, Huang Y, Zhou Y. Genetically encoded tags for real time dissection of protein assembly in living cells. Chem Sci 2018; 9:5551-5555. [PMID: 30061986 PMCID: PMC6048692 DOI: 10.1039/c8sc00839f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 05/22/2018] [Indexed: 12/21/2022] Open
Abstract
Simple methods with straightforward readouts that enable real-time interrogation of protein quaternary structure are much needed to facilitate the physicochemical characterization of proteins at the single-cell level. After screening over a series of microtubule (MT) binders, we report herein the development of two genetically encoded tags (designated as "MoTags" for the monomer/oligomer detection tag) that can be conveniently fused to a given protein to probe its oligomeric state in cellulo when combined with routine fluorescence microscopy. In their monomeric form, MoTags are evenly distributed in the cytosol; whereas oligomerization enables MoTags to label MT or track MT tips in an oligomeric state-dependent manner. We demonstrate here the broad utility of engineered MoTags to aid the determination of protein oligomeric states, dissection of protein structure and function, and monitoring of protein-target interactions under physiological conditions in living cells.
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Affiliation(s)
- Guolin Ma
- Center for Translational Cancer Research , Institute of Biosciences and Technology , College of Medicine , Texas A&M University , 2121 W Holcombe Blvd , Houston , TX 77030 , USA . ;
| | - Qian Zhang
- Center for Translational Cancer Research , Institute of Biosciences and Technology , College of Medicine , Texas A&M University , 2121 W Holcombe Blvd , Houston , TX 77030 , USA . ;
- Department of Infectious Diseases , Renmin Hospital of Wuhan University , Wuhan 430060 , China
| | - Lian He
- Center for Translational Cancer Research , Institute of Biosciences and Technology , College of Medicine , Texas A&M University , 2121 W Holcombe Blvd , Houston , TX 77030 , USA . ;
| | - Nhung T Nguyen
- Center for Translational Cancer Research , Institute of Biosciences and Technology , College of Medicine , Texas A&M University , 2121 W Holcombe Blvd , Houston , TX 77030 , USA . ;
| | - Shuzhong Liu
- Center for Translational Cancer Research , Institute of Biosciences and Technology , College of Medicine , Texas A&M University , 2121 W Holcombe Blvd , Houston , TX 77030 , USA . ;
| | - Zuojiong Gong
- Department of Infectious Diseases , Renmin Hospital of Wuhan University , Wuhan 430060 , China
| | - Yun Huang
- Center for Epigenetics and Disease Prevention , Institute of Biosciences and Technology , College of Medicine , Texas A&M University , 2121 W Holcombe Blvd , Houston , TX 77030 , USA .
- Department of Molecular and Cellular Medicine , College of Medicine , Texas A&M University , College Station , TX 77843 , USA
| | - Yubin Zhou
- Center for Translational Cancer Research , Institute of Biosciences and Technology , College of Medicine , Texas A&M University , 2121 W Holcombe Blvd , Houston , TX 77030 , USA . ;
- Department of Medical Physiology , College of Medicine , Texas A&M University , Temple , TX 76504 , USA
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31
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Chen C, Cummings R, Mordovanakis A, Hunt AJ, Mayer M, Sept D, Yamashita YM. Cytokine receptor-Eb1 interaction couples cell polarity and fate during asymmetric cell division. eLife 2018; 7:33685. [PMID: 29578412 PMCID: PMC5886756 DOI: 10.7554/elife.33685] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2017] [Accepted: 03/25/2018] [Indexed: 12/15/2022] Open
Abstract
Asymmetric stem cell division is a critical mechanism for balancing self-renewal and differentiation. Adult stem cells often orient their mitotic spindle to place one daughter inside the niche and the other outside of it to achieve asymmetric division. It remains unknown whether and how the niche may direct division orientation. Here we discover a novel and evolutionary conserved mechanism that couples cell polarity to cell fate. We show that the cytokine receptor homolog Dome, acting downstream of the niche-derived ligand Upd, directly binds to the microtubule-binding protein Eb1 to regulate spindle orientation in Drosophila male germline stem cells (GSCs). Dome’s role in spindle orientation is entirely separable from its known function in self-renewal mediated by the JAK-STAT pathway. We propose that integration of two functions (cell polarity and fate) in a single receptor is a key mechanism to ensure an asymmetric outcome following cell division.
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Affiliation(s)
- Cuie Chen
- Life Sciences Institute, Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, United States.,Howard Hughes Medical Institute, University of Michigan, Ann Arbor, United States.,Department of Biomedical Engineering, University of Michigan, Ann Arbor, United States
| | - Ryan Cummings
- Life Sciences Institute, Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, United States.,Howard Hughes Medical Institute, University of Michigan, Ann Arbor, United States
| | - Aghapi Mordovanakis
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, United States
| | - Alan J Hunt
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, United States
| | - Michael Mayer
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, United States
| | - David Sept
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, United States
| | - Yukiko M Yamashita
- Life Sciences Institute, Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, United States.,Howard Hughes Medical Institute, University of Michigan, Ann Arbor, United States
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32
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van Haren J, Charafeddine RA, Ettinger A, Wang H, Hahn KM, Wittmann T. Local control of intracellular microtubule dynamics by EB1 photodissociation. Nat Cell Biol 2018; 20:252-261. [PMID: 29379139 PMCID: PMC5826794 DOI: 10.1038/s41556-017-0028-5] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 12/13/2017] [Indexed: 12/18/2022]
Abstract
End-binding proteins, EBs, are adaptors that recruit functionally diverse +TIP proteins to growing microtubule plus ends. To test with high spatial and temporal accuracy how, when and where +TIP protein complexes contribute to dynamic cell biology, we developed a photo-inactivated EB1 variant (π-EB1) by inserting a blue light-sensitive protein-protein interaction module between the microtubule- and +TIP-binding domains of EB1. π-EB1 replaces endogenous EB1 function in the absence of blue light. In contrast, blue light-mediated π-EB1 photo-dissociation results in rapid +TIP complex disassembly, and acutely and reversibly attenuates microtubule growth independent of microtubule end association of the microtubule polymerase CKAP5 (ch-TOG, XMAP215). Local π-EB1 photo-dissociation allows subcellular microtubule dynamics control at the second and micrometre scale, and elicits aversive turning of migrating cancer cells. Importantly, light-mediated domain splitting can serve as template to optically control other intracellular protein activities.
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Affiliation(s)
- Jeffrey van Haren
- Department of Cell and Tissue Biology, University of California, San Francisco, CA, USA
| | - Rabab A Charafeddine
- Department of Cell and Tissue Biology, University of California, San Francisco, CA, USA
| | - Andreas Ettinger
- Department of Cell and Tissue Biology, University of California, San Francisco, CA, USA.,Institute of Epigenetics and Stem Cells, Helmholtz Center Munich, München, Germany
| | - Hui Wang
- University of North Carolina, Chapel Hill, NC, USA
| | - Klaus M Hahn
- University of North Carolina, Chapel Hill, NC, USA
| | - Torsten Wittmann
- Department of Cell and Tissue Biology, University of California, San Francisco, CA, USA.
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33
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Yagi N, Matsunaga S, Hashimoto T. Insights into cortical microtubule nucleation and dynamics in Arabidopsis leaf cells. J Cell Sci 2018; 131:jcs.203778. [PMID: 28615412 DOI: 10.1242/jcs.203778] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Accepted: 06/12/2017] [Indexed: 12/16/2022] Open
Abstract
Plant microtubules (MTs) are nucleated from the γ-tubulin-containing ring complex (γTuRC). In cortical MT arrays of interphase plant cells, γTuRC is preferentially recruited to the lattice of preexisting MTs, where it initiates MT nucleation in either a branch- or bundle-forming manner, or dissociates without mediating nucleation. In this study, we analyzed how γTuRCs influence MT nucleation and dynamics in cotyledon pavement cells of Arabidopsis thaliana We found that γTuRC nucleated MTs at angles of ∼40° toward the plus-ends of existing MTs, or in predominantly antiparallel bundles. A small fraction of γTuRCs was motile and tracked MT ends. When γTuRCs decorated the depolymerizing MT end, they reduced the depolymerization rate. Non-nucleating γTuRCs associated with the MT lattice promoted MT regrowth after a depolymerization phase. These results suggest that γTuRCs not only nucleate MT growth but also regulate MT dynamics by stabilizing MT ends. On rare occasions, a non-MT-associated γTuRC was pushed in the direction of the MT minus-end, while nucleating a new MT, suggesting that the polymerizing plus-end is anchored to the plasma membrane.
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Affiliation(s)
- Noriyoshi Yagi
- Graduate School of Biological Sciences, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan
| | - Sachihiro Matsunaga
- Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan
| | - Takashi Hashimoto
- Graduate School of Biological Sciences, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan
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34
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Duhamel S, Goyette MA, Thibault MP, Filion D, Gaboury L, Côté JF. The E3 Ubiquitin Ligase HectD1 Suppresses EMT and Metastasis by Targeting the +TIP ACF7 for Degradation. Cell Rep 2018; 22:1016-1030. [PMID: 29386124 DOI: 10.1016/j.celrep.2017.12.096] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Revised: 10/28/2017] [Accepted: 12/23/2017] [Indexed: 12/20/2022] Open
Abstract
Cancer cells exploit the epithelial-to-mesenchymal transition (EMT) program to become metastatic. Cytoskeletal regulators are required in mesenchymal cells where they promote EMT and EMT-induced migration. In a search for regulators of metastasis, we conducted shRNA screens targeting the microtubule plus-end tracking proteins (+TIPs). We show that the +TIP ACF7 is essential both for the maintenance of the EMT program and to promote migration. We find that the E3 ubiquitin ligase HectD1 promotes ACF7-proteasome-mediated degradation. Depletion of HectD1 stabilized ACF7, and this enhanced EMT and migration. Decreased HectD1 expression increased metastases in mouse models and conferred increased resistance to the cytotoxic drug cisplatin. A retrospective analysis of biopsies from breast cancer patients also reveals a correlation between higher ACF7 or lower HectD1 expression with poor clinical outcomes. Together, these results suggest that the control of ACF7 levels by HectD1 modulates EMT and the efficiency of metastasis.
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Affiliation(s)
- Stéphanie Duhamel
- Montreal Clinical Research Institute (IRCM), Montréal, QC H2W 1R7, Canada
| | - Marie-Anne Goyette
- Montreal Clinical Research Institute (IRCM), Montréal, QC H2W 1R7, Canada; Molecular Biology Programs, Université de Montréal, Montréal, QC H3T 1J4, Canada
| | | | - Dominic Filion
- Montreal Clinical Research Institute (IRCM), Montréal, QC H2W 1R7, Canada
| | - Louis Gaboury
- Institute for Research in Immunology and Cancer (IRIC), Université de Montréal, Montréal, QC H3C 3J7, Canada; Department of Pathology and Cell Biology, Université de Montréal, Montréal, QC H3C 3J7, Canada
| | - Jean-François Côté
- Montreal Clinical Research Institute (IRCM), Montréal, QC H2W 1R7, Canada; Molecular Biology Programs, Université de Montréal, Montréal, QC H3T 1J4, Canada; Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, QC H3C 3J7, Canada; Department of Anatomy and Cell Biology, McGill University, Montréal, QC H3A 0C7, Canada.
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35
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Weng Z, Shang Y, Yao D, Zhu J, Zhang R. Structural analyses of key features in the KANK1·KIF21A complex yield mechanistic insights into the cross-talk between microtubules and the cell cortex. J Biol Chem 2017; 293:215-225. [PMID: 29158259 DOI: 10.1074/jbc.m117.816017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Revised: 10/30/2017] [Indexed: 12/12/2022] Open
Abstract
The cross-talk between dynamic microtubules and the cell cortex plays important roles in cell division, polarity, and migration. A critical adaptor that links the plus ends of microtubules with the cell cortex is the KANK N-terminal motif and ankyrin repeat domains 1 (KANK1)/kinesin family member 21A (KIF21A) complex. Genetic defects in these two proteins are associated with various cancers and developmental diseases, such as congenital fibrosis of the extraocular muscles type 1. However, the molecular mechanism governing the KANK1/KIF21A interaction and the role of the conserved ankyrin (ANK) repeats in this interaction are still unclear. In this study, we present the crystal structure of the KANK1·KIF21A complex at 2.1 Å resolution. The structure, together with biochemical studies, revealed that a five-helix-bundle-capping domain immediately preceding the ANK repeats of KANK1 forms a structural and functional supramodule with its ANK repeats in binding to an evolutionarily conserved peptide located in the middle of KIF21A. We also show that several missense mutations present in cancer patients are located at the interface of the KANK1·KIF21A complex and destabilize its formation. In conclusion, our study elucidates the molecular basis underlying the KANK1/KIF21A interaction and also provides possible mechanistic explanations for the diseases caused by mutations in KANK1 and KIF21A.
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Affiliation(s)
- Zhuangfeng Weng
- National Center for Protein Science Shanghai, State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 333 Haike Road, Shanghai 201203, China; School of Life Science and Technology, ShanghaiTech University, 100 Haike Road, Shanghai 201210, China
| | - Yuan Shang
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Deqiang Yao
- National Center for Protein Science Shanghai, State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 333 Haike Road, Shanghai 201203, China
| | - Jinwei Zhu
- National Center for Protein Science Shanghai, State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 333 Haike Road, Shanghai 201203, China.
| | - Rongguang Zhang
- National Center for Protein Science Shanghai, State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 333 Haike Road, Shanghai 201203, China; School of Life Science and Technology, ShanghaiTech University, 100 Haike Road, Shanghai 201210, China; Shanghai Research Center, Chinese Academy of Sciences, Shanghai 200031, China.
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36
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Myer NM, Myers KA. CLASP1 regulates endothelial cell branching morphology and directed migration. Biol Open 2017; 6:1502-1515. [PMID: 28860131 PMCID: PMC5665473 DOI: 10.1242/bio.028571] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Endothelial cell (EC) branching is critically dependent upon the dynamic nature of the microtubule (MT) cytoskeleton. Extracellular matrix (ECM) mechanosensing is a prominent mechanism by which cytoskeletal reorganization is achieved; yet how ECM-induced signaling is able to target cytoskeletal reorganization intracellularly to facilitate productive EC branching morphogenesis is not known. Here, we tested the hypothesis that the composition and density of the ECM drive the regulation of MT growth dynamics in ECs by targeting the MT stabilizing protein, cytoplasmic linker associated protein 1 (CLASP1). High-resolution fluorescent microscopy coupled with computational image analysis reveal that CLASP1 promotes slow MT growth on glass ECMs and promotes short-lived MT growth on high-density collagen-I and fibronectin ECMs. Within EC branches, engagement of either high-density collagen-I or high-density fibronectin ECMs results in reduced MT growth speeds, while CLASP1-dependent effects on MT dynamics promotes elevated numbers of short, branched protrusions that guide persistent and directed EC migration. Summary: CLASP1 modulates microtubule dynamics with sub-cellular specificity in response to extracellular matrix density and composition. CLASP1 effects on microtubules promote short, branched protrusions that guide persistent and directional EC migration. This article has an associated First Person interview with the first author of the paper as part of the supplementary information.
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Affiliation(s)
- Nicole M Myer
- Department of Biological Sciences, University of the Sciences in Philadelphia, Philadelphia PA 19104, USA
| | - Kenneth A Myers
- Department of Biological Sciences, University of the Sciences in Philadelphia, Philadelphia PA 19104, USA
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37
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Vemu A, Atherton J, Spector JO, Moores CA, Roll-Mecak A. Tubulin isoform composition tunes microtubule dynamics. Mol Biol Cell 2017; 28:3564-3572. [PMID: 29021343 PMCID: PMC5706985 DOI: 10.1091/mbc.e17-02-0124] [Citation(s) in RCA: 116] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 09/25/2017] [Accepted: 10/03/2017] [Indexed: 12/30/2022] Open
Abstract
We report the cryo-EM structure and dynamic parameters for unmodified α1B/βI+βIVb microtubules. These microtubules display markedly different dynamics compared to heterogeneous brain microtubules, and their dynamic parameters can be proportionally tuned by the addition of a recombinant neuronal tubulin isoform with different dynamic properties. Microtubules polymerize and depolymerize stochastically, a behavior essential for cell division, motility, and differentiation. While many studies advanced our understanding of how microtubule-associated proteins tune microtubule dynamics in trans, we have yet to understand how tubulin genetic diversity regulates microtubule functions. The majority of in vitro dynamics studies are performed with tubulin purified from brain tissue. This preparation is not representative of tubulin found in many cell types. Here we report the 4.2-Å cryo-electron microscopy (cryo-EM) structure and in vitro dynamics parameters of α1B/βI+βIVb microtubules assembled from tubulin purified from a human embryonic kidney cell line with isoform composition characteristic of fibroblasts and many immortalized cell lines. We find that these microtubules grow faster and transition to depolymerization less frequently compared with brain microtubules. Cryo-EM reveals that the dynamic ends of α1B/βI+βIVb microtubules are less tapered and that these tubulin heterodimers display lower curvatures. Interestingly, analysis of EB1 distributions at dynamic ends suggests no differences in GTP cap sizes. Last, we show that the addition of recombinant α1A/βIII tubulin, a neuronal isotype overexpressed in many tumors, proportionally tunes the dynamics of α1B/βI+βIVb microtubules. Our study is an important step toward understanding how tubulin isoform composition tunes microtubule dynamics.
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Affiliation(s)
- Annapurna Vemu
- Cell Biology and Biophysics Unit, National Institute of Neurological Disorders and Stroke, Lung and Blood Institute, Bethesda, MD 20892
| | - Joseph Atherton
- Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck College, University of London, London WC1E 7HX, United Kingdom
| | - Jeffrey O Spector
- Cell Biology and Biophysics Unit, National Institute of Neurological Disorders and Stroke, Lung and Blood Institute, Bethesda, MD 20892
| | - Carolyn A Moores
- Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck College, University of London, London WC1E 7HX, United Kingdom
| | - Antonina Roll-Mecak
- Cell Biology and Biophysics Unit, National Institute of Neurological Disorders and Stroke, Lung and Blood Institute, Bethesda, MD 20892 .,Biophysics Center, National Heart, Lung and Blood Institute, Bethesda, MD 20892
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38
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Liu Y, Visetsouk M, Mynlieff M, Qin H, Lechtreck KF, Yang P. H +- and Na +- elicited rapid changes of the microtubule cytoskeleton in the biflagellated green alga Chlamydomonas. eLife 2017; 6:26002. [PMID: 28875932 PMCID: PMC5779235 DOI: 10.7554/elife.26002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 09/05/2017] [Indexed: 12/27/2022] Open
Abstract
Although microtubules are known for dynamic instability, the dynamicity is considered to be tightly controlled to support a variety of cellular processes. Yet diverse evidence suggests that this is not applicable to Chlamydomonas, a biflagellate fresh water green alga, but intense autofluorescence from photosynthesis pigments has hindered the investigation. By expressing a bright fluorescent reporter protein at the endogenous level, we demonstrate in real time discreet sweeping changes in algal microtubules elicited by rises of intracellular H+ and Na+. These results from this model organism with characteristics of animal and plant cells provide novel explanations regarding how pH may drive cellular processes; how plants may respond to, and perhaps sense stresses; and how organisms with a similar sensitive cytoskeleton may be susceptible to environmental changes.
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Affiliation(s)
- Yi Liu
- Department of Biological Sciences, Marquette University, Milwaukee, United States
| | - Mike Visetsouk
- Department of Biological Sciences, Marquette University, Milwaukee, United States
| | - Michelle Mynlieff
- Department of Biological Sciences, Marquette University, Milwaukee, United States
| | - Hongmin Qin
- Department of Biology, Texas A&M University, College Station, United States
| | - Karl F Lechtreck
- Department of Cellular Biology, University of Georgia, Athen, United States
| | - Pinfen Yang
- Department of Biological Sciences, Marquette University, Milwaukee, United States
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39
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Ivashko-Pachima Y, Sayas CL, Malishkevich A, Gozes I. ADNP/NAP dramatically increase microtubule end-binding protein-Tau interaction: a novel avenue for protection against tauopathy. Mol Psychiatry 2017; 22:1335-1344. [PMID: 28115743 DOI: 10.1038/mp.2016.255] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 11/20/2016] [Accepted: 12/06/2016] [Indexed: 12/30/2022]
Abstract
Activity-dependent neuroprotective protein (ADNP), vital for brain formation and cognitive function, is mutated in autism and linked to neurodegenerative/psychiatric diseases. An eight-amino-acid peptide snippet of ADNP, NAP (NAPVSIPQ), identified as a smallest active fragment, includes the SxIP microtubule (MT) end-binding protein (EB) association motif, and enhances ADNP-EB3 interaction. Depletion of EB1 or EB3 abolishes NAP protection against zinc intoxication. Furthermore, NAP enhances Tau-MT interaction, and Tau regulates the localization and function of EB1 and EB3 in developing neuronal cells. Here, we asked how NAP (ADNP) enhances Tau-MT interactions and whether this is mediated by EBs. We showed, for we believe the first time, that NAP augmented endogenous EB1 comet density in the N1E-115 neuroblastoma neuronal model. This finding was substantiated by cell transfection with fluorescent EB1 and live cell imaging. NAP increased comet amounts, length and speed. At the molecular level, NAP enhanced EB3 homodimer formation, while decreasing EB1-EB3 heterodimer content and driving EB1- and EB3-Tau interactions (dramatic 20-fold increases), leading to recruitment of EB1/EB3 and Tau to MTs under zinc intoxication. Our previous results showed that while NAP protected neuronal-like cells against oxidative stress, it did not protect NIH3T3 fibroblasts. Here, NAP did not protect NIH3T3 cells against zinc intoxication, unless these cells were transfected with Tau. Interestingly, other MT associated proteins (MAPs) may replace Tau, thus, EB-Tau (MAPs) interaction is identified as a novel target for endogenous ADNP neuroprotection, and a future target for drug development, with NAP as a prototype.
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Affiliation(s)
- Y Ivashko-Pachima
- The Lily and Avraham Gildor Chair for the Investigation of Growth Factors, 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 and Adams Super Center for Brain Studies, Tel Aviv University, Tel Aviv, Israel
| | - C Laura Sayas
- Centre for Biomedical Research of the Canary Islands (CIBICAN), Institute for Biomedical Technologies (ITB), University of La Laguna (ULL), Tenerife, Spain
| | - A Malishkevich
- The Lily and Avraham Gildor Chair for the Investigation of Growth Factors, 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 and Adams Super Center for Brain Studies, Tel Aviv University, Tel Aviv, Israel
| | - I Gozes
- The Lily and Avraham Gildor Chair for the Investigation of Growth Factors, 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 and Adams Super Center for Brain Studies, Tel Aviv University, Tel Aviv, Israel
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40
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Shevchenko GV. Putative gravisensors among microtubule associated proteins. Cell Biol Int 2017; 43:983-990. [PMID: 28656641 DOI: 10.1002/cbin.10811] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 06/24/2017] [Indexed: 12/27/2022]
Abstract
Despite of long period of investigation (over 100 years), still a lot of questions remain unclear about molecular mechanisms of plant graviperception. This requires designing new experiments and new approaches to be applied in gravitational biology. Investigation of plant cell reactions under clinorotation (plant disorientation in respect to gravity vector) is of significant importance to such type of research. Clinorotation is known to cause changes of cell polarity and exert mechanical stress in plant cells. Microtubular cytoskeleton is highly dynamic structure and it responds to both of these stresses. Due to turgor pressure and cell elongation, endogenous mechanical forces influence microtubule orientation in order to coordinate cell growth. Rearrangements of microtubules are regulated by numerous associated proteins which functional activity is not fully clear. In this review, we discuss how MT associated proteins regulate cortical MT arrays under mechanical stress and consider how these proteins may act as plant cell gravisensors. Investigation of microtubule associated proteins under clinorotation might shed the light on molecular mechanism of plant cytoskeleton arrangement and its involvement in initial reactions of cell graviperception.
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Affiliation(s)
- Galina V Shevchenko
- Institute of Botany, NAS Ukraine, Cell Biology Department, 2, Tereshchenkivska St., Kiev, 01004, Ukraine
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41
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The Microtubule-Stabilizing Protein CLASP1 Associates with the Theileria annulata Schizont Surface via Its Kinetochore-Binding Domain. mSphere 2017; 2:mSphere00215-17. [PMID: 28861517 PMCID: PMC5566832 DOI: 10.1128/msphere.00215-17] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 07/26/2017] [Indexed: 11/20/2022] Open
Abstract
T. annulata, the only eukaryote known to be capable of transforming another eukaryote, is a widespread parasite of veterinary importance that puts 250 million cattle at risk worldwide and limits livestock development for some of the poorest people in the world. Crucial to the pathology of Theileria is its ability to interact with host microtubules and the mitotic spindle of the infected cell. This study builds on our previous work in investigating the host and parasite molecules involved in mediating this interaction. Because it is not possible to genetically manipulate Theileria schizonts, identifying protein interaction partners is critical to understanding the function of parasite proteins. By identifying two Theileria surface proteins that are involved in the interaction between CLASP1 and the parasite, we provide important insights into the molecular basis of Theileria persistence within a dividing cell. Theileria is an apicomplexan parasite whose presence within the cytoplasm of a leukocyte induces cellular transformation and causes uncontrolled proliferation and clonal expansion of the infected cell. The intracellular schizont utilizes the host cell’s own mitotic machinery to ensure its distribution to both daughter cells by associating closely with microtubules (MTs) and incorporating itself within the central spindle. We show that CLASP1, an MT-stabilizing protein that plays important roles in regulating kinetochore-MT attachment and central spindle positioning, is sequestered at the Theileria annulata schizont surface. We used live-cell imaging and immunofluorescence in combination with MT depolymerization assays to demonstrate that CLASP1 binds to the schizont surface in an MT-independent manner throughout the cell cycle and that the recruitment of the related CLASP2 protein to the schizont is MT dependent. By transfecting Theileria-infected cells with a panel of truncation mutants, we found that the kinetochore-binding domain of CLASP1 is necessary and sufficient for parasite localization, revealing that CLASP1 interaction with the parasite occurs independently of EB1. We overexpressed the MT-binding domain of CLASP1 in parasitized cells. This exhibited a dominant negative effect on host MT stability and led to altered parasite size and morphology, emphasizing the importance of proper MT dynamics for Theileria partitioning during host cell division. Using coimmunoprecipitation, we demonstrate that CLASP1 interacts, directly or indirectly, with the schizont membrane protein p104, and we describe for the first time TA03615, a Theileria protein which localizes to the parasite surface, where it has the potential to participate in parasite-host interactions. IMPORTANCET. annulata, the only eukaryote known to be capable of transforming another eukaryote, is a widespread parasite of veterinary importance that puts 250 million cattle at risk worldwide and limits livestock development for some of the poorest people in the world. Crucial to the pathology of Theileria is its ability to interact with host microtubules and the mitotic spindle of the infected cell. This study builds on our previous work in investigating the host and parasite molecules involved in mediating this interaction. Because it is not possible to genetically manipulate Theileria schizonts, identifying protein interaction partners is critical to understanding the function of parasite proteins. By identifying two Theileria surface proteins that are involved in the interaction between CLASP1 and the parasite, we provide important insights into the molecular basis of Theileria persistence within a dividing cell.
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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: 54] [Impact Index Per Article: 7.7] [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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43
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Potential Role of Microtubule Stabilizing Agents in Neurodevelopmental Disorders. Int J Mol Sci 2017; 18:ijms18081627. [PMID: 28933765 PMCID: PMC5578018 DOI: 10.3390/ijms18081627] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 07/10/2017] [Accepted: 07/18/2017] [Indexed: 01/05/2023] Open
Abstract
Neurodevelopmental disorders (NDDs) are characterized by neuroanatomical abnormalities indicative of corticogenesis disturbances. At the basis of NDDs cortical abnormalities, the principal developmental processes involved are cellular proliferation, migration and differentiation. NDDs are also considered “synaptic disorders” since accumulating evidence suggests that NDDs are developmental brain misconnection syndromes characterized by altered connectivity in local circuits and between brain regions. Microtubules and microtubule-associated proteins play a fundamental role in the regulation of basic neurodevelopmental processes, such as neuronal polarization and migration, neuronal branching and synaptogenesis. Here, the role of microtubule dynamics will be elucidated in regulating several neurodevelopmental steps. Furthermore, the correlation between abnormalities in microtubule dynamics and some NDDs will be described. Finally, we will discuss the potential use of microtubule stabilizing agents as a new pharmacological intervention for NDDs treatment.
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44
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Mustyatsa VV, Boyakhchyan AV, Ataullakhanov FI, Gudimchuk NB. EB-family proteins: Functions and microtubule interaction mechanisms. BIOCHEMISTRY (MOSCOW) 2017; 82:791-802. [DOI: 10.1134/s0006297917070045] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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45
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Nehlig A, Molina A, Rodrigues-Ferreira S, Honoré S, Nahmias C. Regulation of end-binding protein EB1 in the control of microtubule dynamics. Cell Mol Life Sci 2017; 74:2381-2393. [PMID: 28204846 PMCID: PMC11107513 DOI: 10.1007/s00018-017-2476-2] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Revised: 01/13/2017] [Accepted: 01/24/2017] [Indexed: 12/14/2022]
Abstract
The regulation of microtubule dynamics is critical to ensure essential cell functions, such as proper segregation of chromosomes during mitosis or cell polarity and migration. End-binding protein 1 (EB1) is a plus-end-tracking protein (+TIP) that accumulates at growing microtubule ends and plays a pivotal role in the regulation of microtubule dynamics. EB1 autonomously binds an extended tubulin-GTP/GDP-Pi structure at growing microtubule ends and acts as a molecular scaffold that recruits a large number of regulatory +TIPs through interaction with CAP-Gly or SxIP motifs. While extensive studies have focused on the structure of EB1-interacting site at microtubule ends and its role as a molecular platform, the mechanisms involved in the negative regulation of EB1 have only started to emerge and remain poorly understood. In this review, we summarize recent studies showing that EB1 association with MT ends is regulated by post-translational modifications and affected by microtubule-targeting agents. We also present recent findings that structural MAPs, that have no tip-tracking activity, physically interact with EB1 to prevent its accumulation at microtubule plus ends. These observations point out a novel concept of "endogenous EB1 antagonists" and emphasize the importance of finely regulating EB1 function at growing microtubule ends.
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Affiliation(s)
- Anne Nehlig
- Inserm U981, Institut Gustave Roussy, 114 rue Edouard Vaillant, 94800, Villejuif, France
- University Paris Saclay, 94800, Villejuif, France
| | - Angie Molina
- Inserm U981, Institut Gustave Roussy, 114 rue Edouard Vaillant, 94800, Villejuif, France
- University Paris Saclay, 94800, Villejuif, France
- CBD, University of Toulouse-3, Toulouse, France
| | - Sylvie Rodrigues-Ferreira
- Inserm U981, Institut Gustave Roussy, 114 rue Edouard Vaillant, 94800, Villejuif, France
- University Paris Saclay, 94800, Villejuif, France
| | - Stéphane Honoré
- Aix Marseille University, Inserm U-911, CRO2, Marseille, France
- Service Pharmacie, CHU Hôpital de La Timone, APHM, Marseille, France
| | - Clara Nahmias
- Inserm U981, Institut Gustave Roussy, 114 rue Edouard Vaillant, 94800, Villejuif, France.
- University Paris Saclay, 94800, Villejuif, France.
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46
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Howes SC, Geyer EA, LaFrance B, Zhang R, Kellogg EH, Westermann S, Rice LM, Nogales E. Structural differences between yeast and mammalian microtubules revealed by cryo-EM. J Cell Biol 2017; 216:2669-2677. [PMID: 28652389 PMCID: PMC5584162 DOI: 10.1083/jcb.201612195] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2016] [Revised: 03/31/2017] [Accepted: 05/30/2017] [Indexed: 01/03/2023] Open
Abstract
Yeast MTs do not appear to undergo the lattice compaction seen in mammalian MTs upon GTP hydrolysis. Binding of the +TIP Bim1, both between and within αβ-tubulin dimers, causes compaction of yeast MTs and their rapid disassembly. Microtubules are polymers of αβ-tubulin heterodimers essential for all eukaryotes. Despite sequence conservation, there are significant structural differences between microtubules assembled in vitro from mammalian or budding yeast tubulin. Yeast MTs were not observed to undergo compaction at the interdimer interface as seen for mammalian microtubules upon GTP hydrolysis. Lack of compaction might reflect slower GTP hydrolysis or a different degree of allosteric coupling in the lattice. The microtubule plus end–tracking protein Bim1 binds yeast microtubules both between αβ-tubulin heterodimers, as seen for other organisms, and within tubulin dimers, but binds mammalian tubulin only at interdimer contacts. At the concentrations used in cryo-electron microscopy, Bim1 causes the compaction of yeast microtubules and induces their rapid disassembly. Our studies demonstrate structural differences between yeast and mammalian microtubules that likely underlie their differing polymerization dynamics. These differences may reflect adaptations to the demands of different cell size or range of physiological growth temperatures.
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Affiliation(s)
- Stuart C Howes
- Biophysics Graduate Group, University of California, Berkeley, Berkeley, CA
| | - Elisabeth A Geyer
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX.,Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX
| | - Benjamin LaFrance
- Molecular and Cell Biology Graduate Program, University of California, Berkeley, Berkeley, CA
| | - Rui Zhang
- Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA.,Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA
| | - Elizabeth H Kellogg
- Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA.,Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA
| | - Stefan Westermann
- Department of Molecular Genetics, Center for Medical Biotechnology, University of Duisburg-Essen, Essen, Germany
| | - Luke M Rice
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX.,Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX
| | - Eva Nogales
- Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA .,Department of Molecular Biology and California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, CA.,Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA
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47
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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: 4.1] [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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48
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Kruse R, Krantz J, Barker N, Coletta RL, Rafikov R, Luo M, Højlund K, Mandarino LJ, Langlais PR. Characterization of the CLASP2 Protein Interaction Network Identifies SOGA1 as a Microtubule-Associated Protein. Mol Cell Proteomics 2017; 16:1718-1735. [PMID: 28550165 DOI: 10.1074/mcp.ra117.000011] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Indexed: 12/26/2022] Open
Abstract
CLASP2 is a microtubule-associated protein that undergoes insulin-stimulated phosphorylation and co-localization with reorganized actin and GLUT4 at the plasma membrane. To gain insight to the role of CLASP2 in this system, we developed and successfully executed a streamlined interactome approach and built a CLASP2 protein network in 3T3-L1 adipocytes. Using two different commercially available antibodies for CLASP2 and an antibody for epitope-tagged, overexpressed CLASP2, we performed multiple affinity purification coupled with mass spectrometry (AP-MS) experiments in combination with label-free quantitative proteomics and analyzed the data with the bioinformatics tool Significance Analysis of Interactome (SAINT). We discovered that CLASP2 coimmunoprecipitates (co-IPs) the novel protein SOGA1, the microtubule-associated protein kinase MARK2, and the microtubule/actin-regulating protein G2L1. The GTPase-activating proteins AGAP1 and AGAP3 were also enriched in the CLASP2 interactome, although subsequent AGAP3 and CLIP2 interactome analysis suggests a preference of AGAP3 for CLIP2. Follow-up MARK2 interactome analysis confirmed reciprocal co-IP of CLASP2 and revealed MARK2 can co-IP SOGA1, glycogen synthase, and glycogenin. Investigating the SOGA1 interactome confirmed SOGA1 can reciprocal co-IP both CLASP2 and MARK2 as well as glycogen synthase and glycogenin. SOGA1 was confirmed to colocalize with CLASP2 and with tubulin, which identifies SOGA1 as a new microtubule-associated protein. These results introduce the metabolic function of these proposed novel protein networks and their relationship with microtubules as new fields of cytoskeleton-associated protein biology.
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Affiliation(s)
- Rikke Kruse
- From the ‡The Section of Molecular Diabetes & Metabolism, Department of Clinical Research and Institute of Molecular Medicine, University of Southern Denmark, DK-5000 Odense, Denmark.,§Department of Endocrinology, Odense University Hospital, DK-5000 Odense, Denmark
| | - James Krantz
- ¶Department of Medicine, Division of Endocrinology, University of Arizona College of Medicine, Tucson, Arizona 85721
| | - Natalie Barker
- ¶Department of Medicine, Division of Endocrinology, University of Arizona College of Medicine, Tucson, Arizona 85721
| | - Richard L Coletta
- ‖School of Life Sciences, Arizona State University, Tempe, Arizona 85787
| | - Ruslan Rafikov
- ¶Department of Medicine, Division of Endocrinology, University of Arizona College of Medicine, Tucson, Arizona 85721
| | - Moulun Luo
- ¶Department of Medicine, Division of Endocrinology, University of Arizona College of Medicine, Tucson, Arizona 85721
| | - Kurt Højlund
- From the ‡The Section of Molecular Diabetes & Metabolism, Department of Clinical Research and Institute of Molecular Medicine, University of Southern Denmark, DK-5000 Odense, Denmark.,§Department of Endocrinology, Odense University Hospital, DK-5000 Odense, Denmark
| | - Lawrence J Mandarino
- ¶Department of Medicine, Division of Endocrinology, University of Arizona College of Medicine, Tucson, Arizona 85721
| | - Paul R Langlais
- ¶Department of Medicine, Division of Endocrinology, University of Arizona College of Medicine, Tucson, Arizona 85721;
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49
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Breznau EB, Murt M, Blasius TL, Verhey KJ, Miller AL. The MgcRacGAP SxIP motif tethers Centralspindlin to microtubule plus ends in Xenopus laevis. J Cell Sci 2017; 130:1809-1821. [PMID: 28389580 DOI: 10.1242/jcs.195891] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Accepted: 04/04/2017] [Indexed: 12/27/2022] Open
Abstract
Centralspindlin, a complex of the kinesin-6-family member MKLP1 and MgcRacGAP (also known as Kif23 and Racgap1, respectively), is required for cytokinesis and cell-cell junctions. During anaphase, Centralspindlin accumulates at overlapping central spindle microtubules and directs contractile ring formation by recruiting the GEF Ect2 to the cell equator to activate RhoA. We found that MgcRacGAP localized to the plus ends of equatorial astral microtubules during cytokinesis in Xenopus laevis embryos. How MgcRacGAP is stabilized at microtubule plus ends is unknown. We identified an SxIP motif in X. laevis MgcRacGAP that is conserved with other proteins that bind to EB1 (also known as Mapre1), a microtubule plus-end tracking protein. Mutation of the SxIP motif in MgcRacGAP resulted in loss of MgcRacGAP tracking with EB3 (also known as Mapre3) on growing microtubule plus ends, abnormal astral microtubule organization, redistribution of MgcRacGAP from the contractile ring to the polar cell cortex, and mislocalization of RhoA and its downstream targets, which together contributed to severe cytokinesis defects. Furthermore, mutation of the MgcRacGAP SxIP motif perturbed adherens junctions. We propose that the MgcRacGAP SxIP motif is functionally important both for its role in regulating adherens junction structure during interphase and for regulating Rho GTPase activity during cytokinesis.
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Affiliation(s)
- Elaina B Breznau
- Program in Cellular and Molecular Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Megan Murt
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - T Lynne Blasius
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Kristen J Verhey
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Ann L Miller
- Program in Cellular and Molecular Biology, University of Michigan, Ann Arbor, MI 48109, USA .,Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
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50
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Gao Y, Chen H, Lui WY, Lee WM, Cheng CY. Basement Membrane Laminin α2 Regulation of BTB Dynamics via Its Effects on F-Actin and Microtubule Cytoskeletons Is Mediated Through mTORC1 Signaling. Endocrinology 2017; 158:963-978. [PMID: 28323988 PMCID: PMC5460804 DOI: 10.1210/en.2016-1630] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Accepted: 01/11/2017] [Indexed: 11/19/2022]
Abstract
A local axis connects the apical ectoplasmic specialization (ES) at the Sertoli-spermatid interface, the basal ES at the blood-testis barrier (BTB), and the basement membrane across the seminiferous epithelium functionally in rat testes. As such, cellular events that take place simultaneously across the epithelium such as spermiation and BTB remodeling that occur at the apical ES and the basal ES, respectively, at stage VIII of the cycle are coordinated. Herein, laminin α2, a structural component of the basement membrane, was found to regulate BTB dynamics. Sertoli cells were cultured in vitro to allow the establishment of a tight junction (TJ) barrier that mimicked the BTB in vivo. Knockdown of laminin α2 by transfecting Sertoli cells with laminin α2-specific short hairpin RNA vs the nontargeting negative control was shown to perturb the Sertoli cell TJ barrier, illustrating laminin α2 was involved in regulating BTB dynamics. This regulatory effect was mediated through mammalian target of rapamycin complex 1 (mTORC1) signaling because the two mTORC1 downstream signaling molecules ribosomal protein S6 and Akt1/2 were activated and inactivated, respectively, consistent with earlier findings that mTORC1 is involved in promoting BTB remodeling. Also, laminin α2 knockdown induced F-actin and microtubule (MT) disorganization through changes in the spatial expression of F-actin regulators actin-related protein 3 and epidermal growth factor receptor pathway substrate 8 vs end-binding protein 1 (a MT plus-end tracking protein, +TIP). These laminin α2 knockdown-mediated effects on F-actin and MT organization was blocked by exposing Sertoli cells to rapamycin, an inhibitor of mTORC1 signaling, and also SC79, an activator of Akt. In summary, laminin α2-mediated regulation on Sertoli cell BTB dynamics is through mTORC1 signaling.
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Affiliation(s)
- Ying Gao
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York 10065
| | - Haiqi Chen
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York 10065
| | - Wing-yee Lui
- School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - Will M. Lee
- School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - C. Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York 10065
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