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Bearce EA, Ricamona BTB, Fisher KH, O'Hara-Smith JR, Grimes DT. Visualization and quantitation of spine deformity in zebrafish models of scoliosis by micro-computed tomography. STAR Protoc 2023; 4:102739. [PMID: 38043059 PMCID: PMC10775897 DOI: 10.1016/j.xpro.2023.102739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 05/26/2023] [Accepted: 11/07/2023] [Indexed: 12/05/2023] Open
Abstract
Zebrafish (Danio rerio) are increasingly used to investigate spine development, growth, and for studying the etiology of spinal deformity, such as scoliosis. Here, we present a micro-computed tomography-based pipeline for visualizing the zebrafish skeleton. We describe steps for sample preparation, imaging, data management, and processing. We then detail analysis of vertebral and spine morphology using open-source software. This protocol will be useful for scientists using zebrafish to understand spine development and disease. For complete details on the use and execution of this protocol, please refer to Bearce et al. (2022).1.
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Affiliation(s)
- Elizabeth A Bearce
- Institute of Molecular Biology, Department of Biology, University of Oregon, Eugene, OR 97403, USA.
| | - Bryson Tyler B Ricamona
- Institute of Molecular Biology, Department of Biology, University of Oregon, Eugene, OR 97403, USA
| | - Katherine H Fisher
- Institute of Molecular Biology, Department of Biology, University of Oregon, Eugene, OR 97403, USA
| | - Johnathan R O'Hara-Smith
- Institute of Molecular Biology, Department of Biology, University of Oregon, Eugene, OR 97403, USA
| | - Daniel T Grimes
- Institute of Molecular Biology, Department of Biology, University of Oregon, Eugene, OR 97403, USA.
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2
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Bearce EA, Irons ZH, O'Hara-Smith JR, Kuhns CJ, Fisher SI, Crow WE, Grimes DT. Urotensin II-related peptides, Urp1 and Urp2, control zebrafish spine morphology. eLife 2022; 11:e83883. [PMID: 36453722 PMCID: PMC9836392 DOI: 10.7554/elife.83883] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Accepted: 11/24/2022] [Indexed: 12/03/2022] Open
Abstract
The spine provides structure and support to the body, yet how it develops its characteristic morphology as the organism grows is little understood. This is underscored by the commonality of conditions in which the spine curves abnormally such as scoliosis, kyphosis, and lordosis. Understanding the origin of these spinal curves has been challenging in part due to the lack of appropriate animal models. Recently, zebrafish have emerged as promising tools with which to understand the origin of spinal curves. Using zebrafish, we demonstrate that the urotensin II-related peptides (URPs), Urp1 and Urp2, are essential for maintaining spine morphology. Urp1 and Urp2 are 10-amino acid cyclic peptides expressed by neurons lining the central canal of the spinal cord. Upon combined genetic loss of Urp1 and Urp2, adolescent-onset planar curves manifested in the caudal region of the spine. Highly similar curves were caused by mutation of Uts2r3, an URP receptor. Quantitative comparisons revealed that urotensin-associated curves were distinct from other zebrafish spinal curve mutants in curve position and direction. Last, we found that the Reissner fiber, a proteinaceous thread that sits in the central canal and has been implicated in the control of spine morphology, breaks down prior to curve formation in mutants with perturbed cilia motility but was unaffected by loss of Uts2r3. This suggests a Reissner fiber-independent mechanism of curvature in urotensin-deficient mutants. Overall, our results show that Urp1 and Urp2 control zebrafish spine morphology and establish new animal models of spine deformity.
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Affiliation(s)
- Elizabeth A Bearce
- Institute of Molecular Biology, Department of Biology, University of OregonEugeneUnited States
| | - Zoe H Irons
- Institute of Molecular Biology, Department of Biology, University of OregonEugeneUnited States
| | | | - Colin J Kuhns
- Institute of Molecular Biology, Department of Biology, University of OregonEugeneUnited States
| | - Sophie I Fisher
- Institute of Molecular Biology, Department of Biology, University of OregonEugeneUnited States
| | - William E Crow
- Institute of Molecular Biology, Department of Biology, University of OregonEugeneUnited States
| | - Daniel T Grimes
- Institute of Molecular Biology, Department of Biology, University of OregonEugeneUnited States
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3
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Leslie JS, Hjeij R, Vivante A, Bearce EA, Dyer L, Wang J, Rawlins L, Kennedy J, Ubeyratna N, Fasham J, Irons ZH, Craig SB, Koenig J, George S, Pode-Shakked B, Bolkier Y, Barel O, Mane S, Frederiksen KK, Wenger O, Scott E, Cross HE, Lorentzen E, Norris DP, Anikster Y, Omran H, Grimes DT, Crosby AH, Baple EL. Biallelic DAW1 variants cause a motile ciliopathy characterized by laterality defects and subtle ciliary beating abnormalities. Genet Med 2022; 24:2249-2261. [PMID: 36074124 PMCID: PMC10584193 DOI: 10.1016/j.gim.2022.07.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 07/20/2022] [Accepted: 07/20/2022] [Indexed: 01/27/2023] Open
Abstract
PURPOSE The clinical spectrum of motile ciliopathies includes laterality defects, hydrocephalus, and infertility as well as primary ciliary dyskinesia when impaired mucociliary clearance results in otosinopulmonary disease. Importantly, approximately 30% of patients with primary ciliary dyskinesia lack a genetic diagnosis. METHODS Clinical, genomic, biochemical, and functional studies were performed alongside in vivo modeling of DAW1 variants. RESULTS In this study, we identified biallelic DAW1 variants associated with laterality defects and respiratory symptoms compatible with motile cilia dysfunction. In early mouse embryos, we showed that Daw1 expression is limited to distal, motile ciliated cells of the node, consistent with a role in left-right patterning. daw1 mutant zebrafish exhibited reduced cilia motility and left-right patterning defects, including cardiac looping abnormalities. Importantly, these defects were rescued by wild-type, but not mutant daw1, gene expression. In addition, pathogenic DAW1 missense variants displayed reduced protein stability, whereas DAW1 loss-of-function was associated with distal type 2 outer dynein arm assembly defects involving axonemal respiratory cilia proteins, explaining the reduced cilia-induced fluid flow in particle tracking velocimetry experiments. CONCLUSION Our data define biallelic DAW1 variants as a cause of human motile ciliopathy and determine that the disease mechanism involves motile cilia dysfunction, explaining the ciliary beating defects observed in affected individuals.
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Affiliation(s)
- Joseph S Leslie
- Institute of Biomedical and Clinical Science, RILD Wellcome Wolfson Centre, University of Exeter Medical School, Royal Devon University Healthcare NHS Foundation Trust, Exeter, United Kingdom
| | - Rim Hjeij
- Department of General Pediatrics, University Hospital Muenster, Muenster, Germany
| | - Asaf Vivante
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel; Department of Pediatrics B and Pediatric Nephrology Unit, Edmond and Lily Safra Children's Hospital, Sheba Medical Center, Ramat Gan, Israel
| | | | - Laura Dyer
- MRC Harwell Institute, Harwell Campus, Oxfordshire, Oxford, United Kingdom
| | - Jiaolong Wang
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Lettie Rawlins
- Institute of Biomedical and Clinical Science, RILD Wellcome Wolfson Centre, University of Exeter Medical School, Royal Devon University Healthcare NHS Foundation Trust, Exeter, United Kingdom; Peninsula Clinical Genetics Service, Royal Devon University Healthcare NHS Foundation Trust, Exeter, United Kingdom
| | - Joanna Kennedy
- Institute of Biomedical and Clinical Science, RILD Wellcome Wolfson Centre, University of Exeter Medical School, Royal Devon University Healthcare NHS Foundation Trust, Exeter, United Kingdom
| | - Nishanka Ubeyratna
- Institute of Biomedical and Clinical Science, RILD Wellcome Wolfson Centre, University of Exeter Medical School, Royal Devon University Healthcare NHS Foundation Trust, Exeter, United Kingdom
| | - James Fasham
- Institute of Biomedical and Clinical Science, RILD Wellcome Wolfson Centre, University of Exeter Medical School, Royal Devon University Healthcare NHS Foundation Trust, Exeter, United Kingdom; Peninsula Clinical Genetics Service, Royal Devon University Healthcare NHS Foundation Trust, Exeter, United Kingdom
| | - Zoe H Irons
- Institute of Molecular Biology, University of Oregon, Eugene, OR
| | - Samuel B Craig
- Institute of Molecular Biology, University of Oregon, Eugene, OR
| | - Julia Koenig
- Department of General Pediatrics, University Hospital Muenster, Muenster, Germany
| | - Sebastian George
- Department of General Pediatrics, University Hospital Muenster, Muenster, Germany
| | - Ben Pode-Shakked
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel; Metabolic Disease Unit, Edmond and Lily Safra Children's Hospital, Sheba Medical Center, Ramat Gan, Israel
| | - Yoav Bolkier
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel; Pediatric Heart Institute, Edmond and Lily Safra Children's Hospital, Sheba Medical Center, Ramat Gan, Israel
| | - Ortal Barel
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel; The Genomic Unit, Sheba Cancer Research Center, Sheba Medical Center, Ramat Gan, Israel; Wohl Institute for Translational Medicine, Sheba Medical Center, Ramat Gan, Israel
| | - Shrikant Mane
- Department of Genetics, Yale School of Medicine, New Haven, CT
| | | | - Olivia Wenger
- New Leaf Center Clinic for Special Children, Mt Eaton, OH
| | - Ethan Scott
- New Leaf Center Clinic for Special Children, Mt Eaton, OH
| | - Harold E Cross
- Department of Ophthalmology and Vision Science, University of Arizona College of Medicine, University of Arizona, Tucson, AZ
| | - Esben Lorentzen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Dominic P Norris
- MRC Harwell Institute, Harwell Campus, Oxfordshire, Oxford, United Kingdom
| | - Yair Anikster
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel; Metabolic Disease Unit, Edmond and Lily Safra Children's Hospital, Sheba Medical Center, Ramat Gan, Israel; Wohl Institute for Translational Medicine, Sheba Medical Center, Ramat Gan, Israel
| | - Heymut Omran
- Department of General Pediatrics, University Hospital Muenster, Muenster, Germany
| | - Daniel T Grimes
- Institute of Molecular Biology, University of Oregon, Eugene, OR.
| | - Andrew H Crosby
- Institute of Biomedical and Clinical Science, RILD Wellcome Wolfson Centre, University of Exeter Medical School, Royal Devon University Healthcare NHS Foundation Trust, Exeter, United Kingdom.
| | - Emma L Baple
- Institute of Biomedical and Clinical Science, RILD Wellcome Wolfson Centre, University of Exeter Medical School, Royal Devon University Healthcare NHS Foundation Trust, Exeter, United Kingdom; Peninsula Clinical Genetics Service, Royal Devon University Healthcare NHS Foundation Trust, Exeter, United Kingdom.
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Bearce EA, Irons ZH, Craig SB, Kuhns CJ, Sabazali C, Farnsworth DR, Miller AC, Grimes DT. Daw1 regulates the timely onset of cilia motility during development. Development 2022; 149:275714. [PMID: 35708608 PMCID: PMC9270974 DOI: 10.1242/dev.200017] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 05/05/2022] [Indexed: 12/15/2022]
Abstract
Motile cilia generate cell propulsion and extracellular fluid flows that are crucial for airway clearance, fertility and left-right patterning. Motility is powered by dynein arm complexes that are assembled in the cytoplasm then imported into the cilium. Studies in Chlamydomonas reinhardtii showed that ODA16 is a cofactor which promotes dynein arm import. Here, we demonstrate that the zebrafish homolog of ODA16, Daw1, facilitates the onset of robust cilia motility during development. Without Daw1, cilia showed markedly reduced motility during early development; however, motility subsequently increased to attain close to wild-type levels. Delayed motility onset led to differential effects on early and late cilia-dependent processes. Remarkably, abnormal body axis curves, which formed during the first day of development due to reduced cilia motility, self-corrected when motility later reached wild-type levels. Zebrafish larva therefore possess the ability to survey and correct body shape abnormalities. This work defines Daw1 as a factor which promotes the onset of timely cilia motility and can explain why human patients harboring DAW1 mutations exhibit significant laterality perturbations but mild airway and fertility complications. Summary: Daw1 promotes the onset of timely cilia motility for robust axial straightening during zebrafish development.
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Affiliation(s)
- Elizabeth A Bearce
- Institute of Molecular Biology, Department of Biology, University of Oregon, Eugene, OR 97403, USA
| | - Zoe H Irons
- Institute of Molecular Biology, Department of Biology, University of Oregon, Eugene, OR 97403, USA
| | - Samuel B Craig
- Institute of Molecular Biology, Department of Biology, University of Oregon, Eugene, OR 97403, USA
| | - Colin J Kuhns
- Institute of Molecular Biology, Department of Biology, University of Oregon, Eugene, OR 97403, USA
| | - Cynthia Sabazali
- Institute of Molecular Biology, Department of Biology, University of Oregon, Eugene, OR 97403, USA
| | - Dylan R Farnsworth
- Institute of Neuroscience, Department of Biology, University of Oregon, Eugene, OR 97403, USA
| | - Adam C Miller
- Institute of Neuroscience, Department of Biology, University of Oregon, Eugene, OR 97403, USA
| | - Daniel T Grimes
- Institute of Molecular Biology, Department of Biology, University of Oregon, Eugene, OR 97403, USA
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5
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Erdogan B, Bearce EA, Lowery LA. Live Imaging of Cytoskeletal Dynamics in Embryonic Xenopus laevis Growth Cones and Neural Crest Cells. Cold Spring Harb Protoc 2021; 2021:pdb.prot104463. [PMID: 33272974 DOI: 10.1101/pdb.prot104463] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The cytoskeleton is a dynamic, fundamental network that not only provides mechanical strength to maintain a cell's shape but also controls critical events like cell division, polarity, and movement. Thus, how the cytoskeleton is organized and dynamically regulated is critical to our understanding of countless processes. Live imaging of fluorophore-tagged cytoskeletal proteins allows us to monitor the dynamic nature of cytoskeleton components in embryonic cells. Here, we describe a protocol to monitor and analyze cytoskeletal dynamics in primary embryonic neuronal growth cones and neural crest cells obtained from Xenopus laevis embryos.
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Affiliation(s)
- Burcu Erdogan
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, Massachusetts 02138, USA
| | - Elizabeth A Bearce
- Institute of Molecular Biology, Department of Biology, University of Oregon, Eugene, Oregon 97403, USA
| | - Laura Anne Lowery
- Boston University School of Medicine, Boston Medical Center, Boston, Massachusetts 02118, USA
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6
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Bearce EA, Grimes DT. On being the right shape: Roles for motile cilia and cerebrospinal fluid flow in body and spine morphology. Semin Cell Dev Biol 2020; 110:104-112. [PMID: 32693941 DOI: 10.1016/j.semcdb.2020.07.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 07/07/2020] [Accepted: 07/07/2020] [Indexed: 12/12/2022]
Abstract
How developing and growing organisms attain their proper shape is a central problem of developmental biology. In this review, we investigate this question with respect to how the body axis and spine form in their characteristic linear head-to-tail fashion in vertebrates. Recent work in the zebrafish has implicated motile cilia and cerebrospinal fluid flow in axial morphogenesis and spinal straightness. We begin by introducing motile cilia, the fluid flows they generate and their roles in zebrafish development and growth. We then describe how cilia control body and spine shape through sensory cells in the spinal canal, a thread-like extracellular structure called the Reissner fiber, and expression of neuropeptide signals. Last, we discuss zebrafish mutants in which spinal straightness breaks down and three-dimensional curves form. These curves resemble the common but little-understood human disease Idiopathic Scoliosis. Zebrafish research is therefore poised to make progress in our understanding of this condition and, more generally, how body and spine shape is acquired and maintained through development and growth.
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Affiliation(s)
- Elizabeth A Bearce
- Institute of Molecular Biology, Department of Biology, University of Oregon, Eugene, OR, 97403, USA.
| | - Daniel T Grimes
- Institute of Molecular Biology, Department of Biology, University of Oregon, Eugene, OR, 97403, USA.
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Cammarata GM, Bearce EA, Lowery LA. Cytoskeletal social networking in the growth cone: How +TIPs mediate microtubule-actin cross-linking to drive axon outgrowth and guidance. Cytoskeleton (Hoboken) 2016; 73:461-76. [PMID: 26783725 DOI: 10.1002/cm.21272] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Revised: 01/08/2016] [Accepted: 01/08/2016] [Indexed: 11/08/2022]
Abstract
The growth cone is a unique structure capable of guiding axons to their proper destinations. Within the growth cone, extracellular guidance cues are interpreted and then transduced into physical changes in the actin filament (F-actin) and microtubule cytoskeletons, providing direction and movement. While both cytoskeletal networks individually possess important growth cone-specific functions, recent data over the past several years point towards a more cooperative role between the two systems. Facilitating this interaction between F-actin and microtubules, microtubule plus-end tracking proteins (+TIPs) have been shown to link the two cytoskeletons together. Evidence suggests that many +TIPs can couple microtubules to F-actin dynamics, supporting both microtubule advance and retraction in the growth cone periphery. In addition, growing in vitro and in vivo data support a secondary role for +TIPs in which they may participate as F-actin nucleators, thus directly influencing F-actin dynamics and organization. This review focuses on how +TIPs may link F-actin and microtubules together in the growth cone, and how these interactions may influence axon guidance. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
| | | | - Laura Anne Lowery
- Department of Biology, Boston College, Chestnut Hill, Massachusetts.
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8
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Bearce EA, Erdogan B, Lowery LA. TIPsy tour guides: how microtubule plus-end tracking proteins (+TIPs) facilitate axon guidance. Front Cell Neurosci 2015; 9:241. [PMID: 26175669 PMCID: PMC4485311 DOI: 10.3389/fncel.2015.00241] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Accepted: 06/15/2015] [Indexed: 01/01/2023] Open
Abstract
The growth cone is a dynamic cytoskeletal vehicle, which drives the end of a developing axon. It serves to interpret and navigate through the complex landscape and guidance cues of the early nervous system. The growth cone’s distinctive cytoskeletal organization offers a fascinating platform to study how extracellular cues can be translated into mechanical outgrowth and turning behaviors. While many studies of cell motility highlight the importance of actin networks in signaling, adhesion, and propulsion, both seminal and emerging works in the field have highlighted a unique and necessary role for microtubules (MTs) in growth cone navigation. Here, we focus on the role of singular pioneer MTs, which extend into the growth cone periphery and are regulated by a diverse family of microtubule plus-end tracking proteins (+TIPs). These +TIPs accumulate at the dynamic ends of MTs, where they are well-positioned to encounter and respond to key signaling events downstream of guidance receptors, catalyzing immediate changes in microtubule stability and actin cross-talk, that facilitate both axonal outgrowth and turning events.
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Affiliation(s)
| | - Burcu Erdogan
- Department of Biology, Boston College Chestnut Hill, MA, USA
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Nwagbara BU, Faris AE, Bearce EA, Erdogan B, Ebbert PT, Evans MF, Rutherford EL, Enzenbacher TB, Lowery LA. TACC3 is a microtubule plus end-tracking protein that promotes axon elongation and also regulates microtubule plus end dynamics in multiple embryonic cell types. Mol Biol Cell 2014; 25:3350-62. [PMID: 25187649 PMCID: PMC4214782 DOI: 10.1091/mbc.e14-06-1121] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
TACC3 is a microtubule plus end–tracking protein in vertebrates. TACC3 localizes to the extreme microtubule plus end, where it interacts with XMAP215 to regulate microtubule polymerization. TACC3 is also required to promote normal axon outgrowth, likely through its regulation of microtubule dynamics within the growth cone. Microtubule plus end dynamics are regulated by a conserved family of proteins called plus end–tracking proteins (+TIPs). It is unclear how various +TIPs interact with each other and with plus ends to control microtubule behavior. The centrosome-associated protein TACC3, a member of the transforming acidic coiled-coil (TACC) domain family, has been implicated in regulating several aspects of microtubule dynamics. However, TACC3 has not been shown to function as a +TIP in vertebrates. Here we show that TACC3 promotes axon outgrowth and regulates microtubule dynamics by increasing microtubule plus end velocities in vivo. We also demonstrate that TACC3 acts as a +TIP in multiple embryonic cell types and that this requires the conserved C-terminal TACC domain. Using high-resolution live-imaging data on tagged +TIPs, we show that TACC3 localizes to the extreme microtubule plus end, where it lies distal to the microtubule polymerization marker EB1 and directly overlaps with the microtubule polymerase XMAP215. TACC3 also plays a role in regulating XMAP215 stability and localizing XMAP215 to microtubule plus ends. Taken together, our results implicate TACC3 as a +TIP that functions with XMAP215 to regulate microtubule plus end dynamics.
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Affiliation(s)
| | - Anna E Faris
- Department of Biology, Boston College, Chestnut Hill, MA 02467
| | | | - Burcu Erdogan
- Department of Biology, Boston College, Chestnut Hill, MA 02467
| | | | - Matthew F Evans
- Department of Biology, Boston College, Chestnut Hill, MA 02467
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