1
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Xu R, Du S. Overexpression of Lifeact-GFP Disrupts F-Actin Organization in Cardiomyocytes and Impairs Cardiac Function. Front Cell Dev Biol 2021; 9:746818. [PMID: 34765602 PMCID: PMC8576398 DOI: 10.3389/fcell.2021.746818] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Accepted: 10/07/2021] [Indexed: 11/28/2022] Open
Abstract
Lifeact-GFP is a frequently used molecular probe to study F-actin structure and dynamic assembly in living cells. In this study, we generated transgenic zebrafish models expressing Lifeact-GFP specifically in cardiac muscles to investigate the effect of Lifeact-GFP on heart development and its application to study cardiomyopathy. The data showed that transgenic zebrafish with low to moderate levels of Lifeact-GFP expression could be used as a good model to study contractile dynamics of actin filaments in cardiac muscles in vivo. Using this model, we demonstrated that loss of Smyd1b, a lysine methyltransferase, disrupted F-actin filament organization in cardiomyocytes of zebrafish embryos. Our studies, however, also demonstrated that strong Lifeact-GFP expression in cardiomyocytes was detrimental to actin filament organization in cardiomyocytes that led to pericardial edema and early embryonic lethality of zebrafish embryos. Collectively, these data suggest that although Lifeact-GFP is a good probe for visualizing F-actin dynamics, transgenic models need to be carefully evaluated to avoid artifacts induced by Lifeact-GFP overexpression.
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Affiliation(s)
| | - Shaojun Du
- Department of Biochemistry and Molecular Biology, Institute of Marine and Environmental Technology, University of Maryland School of Medicine, Baltimore, MD, United States
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2
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Balaraju AK, Hu B, Rodriguez JJ, Murry M, Lin F. Glypican 4 regulates planar cell polarity of endoderm cells by controlling the localization of Cadherin 2. Development 2021; 148:dev199421. [PMID: 34131730 PMCID: PMC8313861 DOI: 10.1242/dev.199421] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 06/09/2021] [Indexed: 11/20/2022]
Abstract
Noncanonical Wnt/planar cell polarity (Wnt/PCP) signaling has been implicated in endoderm morphogenesis. However, the underlying cellular and molecular mechanisms of this process are unclear. We found that, during convergence and extension (C&E) in zebrafish, gut endodermal cells are polarized mediolaterally, with GFP-Vangl2 enriched at the anterior edges. Endoderm cell polarity is lost and intercalation is impaired in the absence of glypican 4 (gpc4), a heparan-sulfate proteoglycan that promotes Wnt/PCP signaling, suggesting that this signaling is required for endodermal cell polarity. Live imaging revealed that endoderm C&E is accomplished by polarized cell protrusions and junction remodeling, which are impaired in gpc4-deficient endodermal cells. Furthermore, in the absence of gpc4, Cadherin 2 expression on the endodermal cell surface is increased as a result of impaired Rab5c-mediated endocytosis, which partially accounts for the endodermal defects in these mutants. These findings indicate that Gpc4 regulates endodermal planar cell polarity during endoderm C&E by influencing the localization of Cadherin 2. Thus, our study uncovers a new mechanism by which Gpc4 regulates planar cell polarity and reveals the role of Wnt/PCP signaling in endoderm morphogenesis.
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Affiliation(s)
| | | | | | | | - Fang Lin
- Department of Anatomy and Cell Biology, Carver College of Medicine, The University of Iowa, Iowa City, IA 52242, USA
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3
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Marsay KS, Greaves S, Mahabaleshwar H, Ho CM, Roehl H, Monk PN, Carney TJ, Partridge LJ. Tetraspanin Cd9b and Cxcl12a/Cxcr4b have a synergistic effect on the control of collective cell migration. PLoS One 2021; 16:e0260372. [PMID: 34847198 PMCID: PMC8631670 DOI: 10.1371/journal.pone.0260372] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 11/08/2021] [Indexed: 11/30/2022] Open
Abstract
Collective cell migration is essential for embryonic development and homeostatic processes. During zebrafish development, the posterior lateral line primordium (pLLP) navigates along the embryo flank by collective cell migration. The chemokine receptors, Cxcr4b and Cxcr7b, as well as their cognate ligand, Cxcl12a, are essential for this process. We corroborate that knockdown of the zebrafish cd9 tetraspanin orthologue, cd9b, results in mild pLL abnormalities. Through generation of CRISPR and TALEN mutants, we show that cd9a and cd9b function partially redundantly in pLLP migration, which is delayed in the cd9b single and cd9a; cd9b double mutants. This delay led to a transient reduction in neuromast numbers. Loss of both Cd9a and Cd9b sensitized embryos to reduced Cxcr4b and Cxcl12a levels. Together these results provide evidence that Cd9 modulates collective cell migration of the pLLP during zebrafish development. One interpretation of these observations is that Cd9 contributes to more effective chemokine signalling.
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Affiliation(s)
- Katherine S. Marsay
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, United Kingdom
- Department of Infection, Immunity and Cardiovascular Science, University of Sheffield, Sheffield, United Kingdom
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, Singapore, Singapore
| | - Sarah Greaves
- Department of Biomedical Science, University of Sheffield, Sheffield, United Kingdom
| | - Harsha Mahabaleshwar
- Lee Kong Chian School of Medicine, Experimental Medicine Building, Yunnan Garden Campus, Nanyang Technological University, Singapore, Singapore
| | - Charmaine Min Ho
- Lee Kong Chian School of Medicine, Experimental Medicine Building, Yunnan Garden Campus, Nanyang Technological University, Singapore, Singapore
| | - Henry Roehl
- Department of Biomedical Science, University of Sheffield, Sheffield, United Kingdom
- * E-mail:
| | - Peter N. Monk
- Department of Infection, Immunity and Cardiovascular Science, University of Sheffield, Sheffield, United Kingdom
| | - Tom J. Carney
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, Singapore, Singapore
- Lee Kong Chian School of Medicine, Experimental Medicine Building, Yunnan Garden Campus, Nanyang Technological University, Singapore, Singapore
| | - Lynda J. Partridge
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, United Kingdom
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4
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Olson HM, Nechiporuk AV. Lamellipodia-like protrusions and focal adhesions contribute to collective cell migration in zebrafish. Dev Biol 2020; 469:125-134. [PMID: 33096063 DOI: 10.1016/j.ydbio.2020.10.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 10/15/2020] [Accepted: 10/16/2020] [Indexed: 02/09/2023]
Abstract
Collective cell migration is a process where cohorts of cells exhibit coordinated migratory behavior. During individual and collective cellular migration, cells must extend protrusions to interact with the extracellular environment, sense chemotactic cues, and act as points of attachment. The mechanisms and regulators of protrusive behavior have been widely studied in individually migrating cells; however, how this behavior is regulated throughout collectives is not well understood. To address this, we used the zebrafish posterior lateral line primordium (pLLP) as a model. The pLLP is a cluster of ~150 cells that migrates along the zebrafish trunk, depositing groups of cells that will become sensory organs. To define protrusive behavior, we performed mosaic analysis to sparsely label pLLP cells with a transgene marking filamentous actin. This approach revealed an abundance of brush-like protrusions throughout the pLLP that orient in the direction of migration. Formation of these protrusions depends on the Arp2/3 complex, a regulator of dendritic actin. This argues that these brush-like protrusions are an in vivo example of lamellipodia. Mosaic analysis demonstrated that these lamellipodia-like protrusions are located in a close proximity to the overlying skin. Immunostaining revealed an abundance of focal adhesion complexes surrounding the pLLP. Disruption of these complexes specifically in pLLP cells led to impaired pLLP migration. Finally, we show that Erk signaling, a known regulator of focal adhesions, is required for proper formation of lamellipodia-like protrusions and pLLP migration. Altogether, our results suggest a model where the coordinated dynamics of lamellipodia-like protrusions, making contact with either the overlying skin or the extracellular matrix through focal adhesions, promotes migration of pLLP cells.
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Affiliation(s)
- Hannah M Olson
- Department Cell, Developmental & Cancer Biology, Oregon Health & Science University, The Knight Cancer Institute, Portland, OR, USA; Neuroscience Graduate Program, Oregon Health & Science University, Portland, OR, USA
| | - Alex V Nechiporuk
- Department Cell, Developmental & Cancer Biology, Oregon Health & Science University, The Knight Cancer Institute, Portland, OR, USA.
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5
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Lee GH, Chang CL, Chiu WT, Hsiao TH, Chen PY, Wang KC, Kuo CH, Chen BH, Shi GY, Wu HL, Fu TF. A thrombomodulin-like gene is crucial to the collective migration of epibolic blastomeres during germ layer formation and organogenesis in zebrafish. J Biomed Sci 2019; 26:60. [PMID: 31451113 PMCID: PMC6709559 DOI: 10.1186/s12929-019-0549-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Accepted: 07/25/2019] [Indexed: 12/02/2022] Open
Abstract
Background Thrombomodulin (TM), an integral membrane protein, has long been known for its anticoagulant activity. Recent studies showed that TM displays multifaceted activities, including the involvement in cell adhesion and collective cell migration in vitro. However, whether TM contributes similarly to these biological processes in vivo remains elusive. Methods We adapted zebrafish, a prominent animal model for studying molecular/cellular activity, embryonic development, diseases mechanism and drug discovery, to examine how TM functions in modulating cell migration during germ layer formation, a normal and crucial physiological process involving massive cell movement in the very early stages of life. In addition, an in vivo assay was developed to examine the anti-hemostatic activity of TM in zebrafish larva. Results We found that zebrafish TM-b, a zebrafish TM-like protein, was expressed mainly in vasculatures and displayed anti-hemostatic activity. Knocking-down TM-b led to malformation of multiple organs, including vessels, heart, blood cells and neural tissues. Delayed epiboly and incoherent movement of yolk syncytial layer were also observed in early TM-b morphants. Whole mount immunostaining revealed the co-localization of TM-b with both actin and microtubules in epibolic blastomeres. Single-cell tracking revealed impeded migration of blastomeres during epiboly in TM-b-deficient embryos. Conclusion Our results showed that TM-b is crucial to the collective migration of blastomeres during germ layer formation. The structural and functional compatibility and conservation between zebrafish TM-b and mammalian TM support the properness of using zebrafish as an in vivo platform for studying the biological significance and medical use of TM. Electronic supplementary material The online version of this article (10.1186/s12929-019-0549-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Gang-Hui Lee
- The Institute of Basic Medical Science College of Medicine, National Cheng Kung University, Tainan, Taiwan.,International Center for Wound Repair and Regeneration, National Cheng Kung University, Tainan, Taiwan
| | - Chia-Lin Chang
- Department of Biochemistry and Molecular Biology, National Cheng Kung University College of Medicine, Tainan, Taiwan.,Cardiovascular Research Center College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Wen-Tai Chiu
- Department of Biomedical Engineering College of Engineering, National Cheng Kung University, Tainan, Taiwan
| | - Tsun-Hsien Hsiao
- The Institute of Basic Medical Science College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Po-Yuan Chen
- The Institute of Basic Medical Science College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Kuan-Chieh Wang
- Department of Medical Laboratory Science and Biotechnology, National Cheng Kung University College of Medicine, Tainan, Taiwan.,Department of Food Safety/ Hygiene and Risk Management College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Department of Pharmacy College of Pharmacy and Science, Chia Nan University of Pharmacy and Science, Tainan, Taiwan
| | - Cheng-Hsiang Kuo
- Department of Biochemistry and Molecular Biology, National Cheng Kung University College of Medicine, Tainan, Taiwan
| | - Bing-Hung Chen
- Department of Biotechnology, Kaohsiung Medical University, Kaohsiung, Taiwan.,The Institute of Biomedical Sciences, National Sun Yat-sen University, Kaohsiung, Taiwan
| | - Guey-Yueh Shi
- The Institute of Basic Medical Science College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Department of Biochemistry and Molecular Biology, National Cheng Kung University College of Medicine, Tainan, Taiwan.,Cardiovascular Research Center College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Hua-Lin Wu
- The Institute of Basic Medical Science College of Medicine, National Cheng Kung University, Tainan, Taiwan. .,Department of Biochemistry and Molecular Biology, National Cheng Kung University College of Medicine, Tainan, Taiwan. .,Cardiovascular Research Center College of Medicine, National Cheng Kung University, Tainan, Taiwan.
| | - Tzu-Fun Fu
- The Institute of Basic Medical Science College of Medicine, National Cheng Kung University, Tainan, Taiwan. .,Department of Medical Laboratory Science and Biotechnology, National Cheng Kung University College of Medicine, Tainan, Taiwan.
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6
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Urasaki A, Morishita S, Naka K, Uozumi M, Abe K, Huang L, Watase E, Nakagawa O, Kawakami K, Matsui T, Bessho Y, Inagaki N. Shootins mediate collective cell migration and organogenesis of the zebrafish posterior lateral line system. Sci Rep 2019; 9:12156. [PMID: 31434971 PMCID: PMC6704158 DOI: 10.1038/s41598-019-48585-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Accepted: 08/07/2019] [Indexed: 01/23/2023] Open
Abstract
The zebrafish sensory posterior lateral line is an excellent model system to study collective cell migration and organogenesis. Shootin1 is a cytoplasmic protein involved in neuronal polarization and axon guidance. Previous studies have shown that shootin1 couples actin filament retrograde flow with extracellular adhesive substrates at the leading edge of axonal growth cones, thereby producing mechanical force for the migration and guidance of axonal growth cones. However, the functions of shootin in peripheral cells remain unknown. Here we identified two novel shootin family members, shootin2 and shootin3. In zebrafish, shootin1 and shootin3 are expressed in the posterior lateral line primordium (PLLP) and neuromasts during embryonic development. A shootin1 mutant displayed a reduced speed of PLLP migration, while shootin1;shootin3 double mutation inhibited cell proliferation in the PLLP. Furthermore, our results suggest that shootin1 and shootin3 positively regulate the number of neuromasts and the number of cells in deposited neuromasts. Our study demonstrates that shootins mediate collective cell migration of the posterior lateral line primordium and formation of neuromasts in zebrafish.
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Affiliation(s)
- Akihiro Urasaki
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara, 630-0192, Japan.,Department of Molecular Physiology, National Cerebral and Cardiovascular Center Research Institute, 6-1 Kishibe-Shinmachi, Suita, Osaka, 564-8565, Japan
| | - Seiya Morishita
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara, 630-0192, Japan
| | - Kosuke Naka
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara, 630-0192, Japan
| | - Minato Uozumi
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara, 630-0192, Japan
| | - Kouki Abe
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara, 630-0192, Japan
| | - Liguo Huang
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara, 630-0192, Japan
| | - Emiko Watase
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara, 630-0192, Japan
| | - Osamu Nakagawa
- Department of Molecular Physiology, National Cerebral and Cardiovascular Center Research Institute, 6-1 Kishibe-Shinmachi, Suita, Osaka, 564-8565, Japan
| | - Koichi Kawakami
- Division of Molecular and Developmental Biology, National Institute of Genetics, and Department of Genetics, SOKENDAI (The Graduate University for Advanced Studies), Mishima, Shizuoka, 411-8540, Japan
| | - Takaaki Matsui
- Laboratory of Gene Regulation Research, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara, 630-0192, Japan
| | - Yasumasa Bessho
- Laboratory of Gene Regulation Research, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara, 630-0192, Japan
| | - Naoyuki Inagaki
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara, 630-0192, Japan.
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7
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Guo Y, He X, Zhao L, Liu L, Song H, Wang X, Xu J, Ju X, Guo W, Zhu X. Gβ2 Regulates the Multipolar-Bipolar Transition of Newborn Neurons in the Developing Neocortex. Cereb Cortex 2018; 27:3414-3426. [PMID: 28334111 DOI: 10.1093/cercor/bhx042] [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: 08/12/2016] [Indexed: 01/14/2023] Open
Abstract
Proper neuronal migration is critical for the formation of the six-layered neocortex in the mammalian brain. However, the precise control of neuronal migration is not well understood. Heterotrimeric guanine nucleotide binding proteins (G proteins), composed of Gα and Gβγ, transduce signals from G protein-coupled receptors to downstream effectors and play crucial roles in brain development. However, the functions of individual subunits of G proteins in prenatal brain development remain unclear. Here, we report that Gβ2 is expressed in the embryonic neocortex, with abundant expression in the intermediate zone, and is significantly upregulated in differentiated neurons. Perturbation of Gβ2 expression impairs the morphogenetic transformation of migrating neurons from multipolar to bipolar and subsequently delays neuronal migration. Moreover, Gβ2 acts as a scaffold protein to organize the MP1-MEK1-ERK1/2 complex and mediates the phosphorylation of ERK1/2. Importantly, expression of a constitutively active variant of MEK1 rescues the migration defects that are caused by the loss of Gβ2. In conclusion, our findings reveal that Gβ2 regulates proper neuronal migration during neocortex development by activating the ERK1/2 signaling pathway.
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Affiliation(s)
- Ye Guo
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University, Changchun 130024, China
| | - Xiaoxiao He
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University, Changchun 130024, China
| | - Lu Zhao
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University, Changchun 130024, China
| | - Lin Liu
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University, Changchun 130024, China
| | - Huifang Song
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University, Changchun 130024, China
| | - Xudong Wang
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University, Changchun 130024, China
| | - Jiahui Xu
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University, Changchun 130024, China
| | - Xingda Ju
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University, Changchun 130024, China
| | - Weixiang Guo
- State Key Laboratory for Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Xiaojuan Zhu
- Key Laboratory of Molecular Epigenetics, Ministry of Education and Institute of Cytology and Genetics, Northeast Normal University, Changchun 130024, China
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8
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Wang X, Hou H, Song K, Zhang Z, Zhang S, Cao Y, Chen L, Sang Q, Lin F, Xu H. Lpar2b Controls Lateral Line Tissue Size by Regulating Yap1 Activity in Zebrafish. Front Mol Neurosci 2018; 11:34. [PMID: 29479307 PMCID: PMC5812253 DOI: 10.3389/fnmol.2018.00034] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2017] [Accepted: 01/25/2018] [Indexed: 12/16/2022] Open
Abstract
LPA signaling plays important roles during cell migration and proliferation in normal and pathological conditions. However, its role during sensory organ development remains unknown. Here we show a LPA receptor Lpar2b is expressed in the posterior lateral line primordium (pLLP) and mechanosensory organs called neuromasts (NMs) in zebrafish embryos. Lpar2b loss-of-function significantly reduces the number of NMs and hair cells in the posterior lateral line (pLL). Further analysis reveals that Lpar2b regulates the patterning and tissue size of the pLLP. Interestingly, we show that knocking down a Hippo effector Yap1 phenocopies the result of Lpar2b depletion, and Lpar2b regulates the phosphorylation and activity of Yap1 in the pLLP. Importantly, a phosphorylation-resistant Yap1 rescues pLLP size and NM number in Lpar2b-depleted embryos. Our results indicate Lpar2b controls primordium size and NM number by regulating Yap1 activity in the lateral line system.
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Affiliation(s)
- Xueqian Wang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China.,State Key Laboratory of Genetic Engineering, Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Haitao Hou
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Kaida Song
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Zhiqiang Zhang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Shuqiang Zhang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Ying Cao
- School of Life Science and Technology, Tongji University, Shanghai, China
| | - Liming Chen
- Biochemistry and Biological Product Institute, School of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Qing Sang
- MOE Key Laboratory of Contemporary Anthropology and School of Life Sciences, Fudan University, Shanghai, China
| | - Fang Lin
- Department of Anatomy and Cell Biology, Carver College of Medicine, University of Iowa, Iowa City, IA, United States
| | - Hui Xu
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China
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9
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Mib1 contributes to persistent directional cell migration by regulating the Ctnnd1-Rac1 pathway. Proc Natl Acad Sci U S A 2017; 114:E9280-E9289. [PMID: 29078376 DOI: 10.1073/pnas.1712560114] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Persistent directional cell migration is involved in animal development and diseases. The small GTPase Rac1 is involved in F-actin and focal adhesion dynamics. Local Rac1 activity is required for persistent directional migration, whereas global, hyperactivated Rac1 enhances random cell migration. Therefore, precise control of Rac1 activity is important for proper directional cell migration. However, the molecular mechanism underlying the regulation of Rac1 activity in persistent directional cell migration is not fully understood. Here, we show that the ubiquitin ligase mind bomb 1 (Mib1) is involved in persistent directional cell migration. We found that knockdown of MIB1 led to an increase in random cell migration in HeLa cells in a wound-closure assay. Furthermore, we explored novel Mib1 substrates for cell migration and found that Mib1 ubiquitinates Ctnnd1. Mib1-mediated ubiquitination of Ctnnd1 K547 attenuated Rac1 activation in cultured cells. In addition, we found that posterior lateral line primordium cells in the zebrafish mib1ta52b mutant showed increased random migration and loss of directional F-actin-based protrusion formation. Knockdown of Ctnnd1 partially rescued posterior lateral line primordium cell migration defects in the mib1ta52b mutant. Taken together, our data suggest that Mib1 plays an important role in cell migration and that persistent directional cell migration is regulated, at least in part, by the Mib1-Ctnnd1-Rac1 pathway.
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10
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Gβ1 is required for neutrophil migration in zebrafish. Dev Biol 2017; 428:135-147. [PMID: 28554852 DOI: 10.1016/j.ydbio.2017.05.024] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Revised: 05/23/2017] [Accepted: 05/24/2017] [Indexed: 11/20/2022]
Abstract
Signaling mediated by G protein-coupled receptors (GPCRs) is essential for the migration of cells toward chemoattractants. The recruitment of neutrophils to injured tissues in zebrafish larvae is a useful model for studying neutrophil migration and trafficking in vivo. Indeed, the study of this process led to the discovery that PI3Kγ is required for the polarity and motility of neutrophils, features that are necessary for the directed migration of these cells to wounds. However, the mechanism by which PI3Kγ is activated remains to be determined. Here we show that signaling by specifically the heterotrimeric G protein subunit Gβ1 is critical for neutrophil migration in response to wounding. In embryos treated with small-molecule inhibitors of Gβγ signaling, neutrophils failed to migrate to wound sites. Although both the Gβ1 and Gβ4 isoforms are expressed in migrating neutrophils, only deficiency for the former (morpholino-based knockdown) interfered with the directed migration of neutrophils towards wounds. The Gβ1 deficiency also impaired the ability of cells to change cell shape and reduced their general motility, defects that are similar to those in neutrophils deficient for PI3Kγ. Transplantation assays showed that the requirement for Gβ1 in neutrophil migration is cell autonomous. Finally, live imaging revealed that Gβ1 is required for polarized activation of PI3K, and for the actin dynamics that enable neutrophil migration. Collectively, our data indicate that Gβ1 signaling controls proper neutrophil migration by activating PI3K and modulating actin dynamics. Moreover, they illustrate a role for a specific Gβ isoform in chemotaxis in vivo.
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11
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Mizoguchi T, Kawakami K, Itoh M. Zebrafish lines expressing UAS-driven red probes for monitoring cytoskeletal dynamics. Genesis 2016; 54:483-9. [PMID: 27342687 DOI: 10.1002/dvg.22955] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Revised: 06/20/2016] [Accepted: 06/22/2016] [Indexed: 01/01/2023]
Abstract
Actin filaments and microtubules are principal components of the cytoskeleton that regulate the basic cellular phenomena underlying many fundamental cellular processes. Therefore, analyzing their dynamics in living cells is important for understanding cellular events more precisely. In this article, we report two novel transgenic zebrafish lines expressing red fluorescent proteins tagged with Lifeact or EB1 that interact with actin filaments and microtubule plus ends, respectively, under the control of the GAL4-UAS system. Using these transgenic lines, we could detect F-actin and microtubule plus end dynamics in specific tissues of living zebrafish embryos by crossing with GAL4 driver lines. In addition, we could achieve multi-color imaging using these transgenic lines with GFP-expressing transgenic lines. Therefore, our transgenic lines that carry UAS-driven red fluorescent cytoskeletal probes are useful tools for analyzing spatiotemporal changes of the cytoskeletal elements using multicolor live imaging.
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Affiliation(s)
| | - Koichi Kawakami
- Division of Molecular and Developmental Biology, National Institute of Genetics, Mishima, Japan
| | - Motoyuki Itoh
- Graduate School of Pharmaceutical Science, Chiba University, Japan.
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12
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Tahara N, Brush M, Kawakami Y. Cell migration during heart regeneration in zebrafish. Dev Dyn 2016; 245:774-87. [PMID: 27085002 PMCID: PMC5839122 DOI: 10.1002/dvdy.24411] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Revised: 03/17/2016] [Accepted: 04/12/2016] [Indexed: 12/27/2022] Open
Abstract
Zebrafish possess the remarkable ability to regenerate injured hearts as adults, which contrasts the very limited ability in mammals. Although very limited, mammalian hearts do in fact have measurable levels of cardiomyocyte regeneration. Therefore, elucidating mechanisms of zebrafish heart regeneration would provide information of naturally occurring regeneration to potentially apply to mammalian studies, in addition to addressing this biologically interesting phenomenon in itself. Studies over the past 13 years have identified processes and mechanisms of heart regeneration in zebrafish. After heart injury, pre-existing cardiomyocytes dedifferentiate, enter the cell cycle, and repair the injured myocardium. This process requires interaction with epicardial cells, endocardial cells, and vascular endothelial cells. Epicardial cells envelope the heart, while endocardial cells make up the inner lining of the heart. They provide paracrine signals to cardiomyocytes to regenerate the injured myocardium, which is vascularized during heart regeneration. In addition, accumulating results suggest that local migration of these major cardiac cell types have roles in heart regeneration. In this review, we summarize the characteristics of various heart injury methods used in the research community and regeneration of the major cardiac cell types. Then, we discuss local migration of these cardiac cell types and immune cells during heart regeneration. Developmental Dynamics 245:774-787, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Naoyuki Tahara
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, Minnesota
- Stem Cell Institute, University of Minnesota, Minneapolis, Minnesota
| | - Michael Brush
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, Minnesota
| | - Yasuhiko Kawakami
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, Minnesota
- Stem Cell Institute, University of Minnesota, Minneapolis, Minnesota
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A Subpopulation of Label-Retaining Cells of the Kidney Papilla Regenerates Injured Kidney Medullary Tubules. Stem Cell Reports 2016; 6:757-771. [PMID: 27117784 PMCID: PMC4939828 DOI: 10.1016/j.stemcr.2016.03.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Revised: 03/22/2016] [Accepted: 03/23/2016] [Indexed: 12/17/2022] Open
Abstract
To determine whether adult kidney papillary label-retaining cells (pLRCs) are specialized precursors, we analyzed their transcription profile. Among genes overexpressed in pLRCs, we selected candidate genes to perform qPCR and immunodetection of their encoded proteins. We found that Zfyve27, which encodes protrudin, identified a subpopulation of pLRCs. With Zfyve27-CreERT2 transgenic and reporter mice we generated bitransgenic animals and performed cell-lineage analysis. Post tamoxifen, Zfyve27-CreERT2 marked cells preferentially located in the upper part of the papilla. These cells were low cycling and did not generate progeny even after long-term observation, thus they did not appear to contribute to kidney homeostasis. However, after kidney injury, but only if severe, they activated a program of proliferation, migration, and morphogenesis generating multiple and long tubular segments. Remarkably these regenerated tubules were located preferentially in the kidney medulla, indicating that repair of injury in the kidney is regionally specified. These results suggest that different parts of the kidney have different progenitor cell pools.
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Mayor R, Etienne-Manneville S. The front and rear of collective cell migration. Nat Rev Mol Cell Biol 2016; 17:97-109. [PMID: 26726037 DOI: 10.1038/nrm.2015.14] [Citation(s) in RCA: 514] [Impact Index Per Article: 64.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Collective cell migration has a key role during morphogenesis and during wound healing and tissue renewal in the adult, and it is involved in cancer spreading. In addition to displaying a coordinated migratory behaviour, collectively migrating cells move more efficiently than if they migrated separately, which indicates that a cellular interplay occurs during collective cell migration. In recent years, evidence has accumulated confirming the importance of such intercellular communication and exploring the molecular mechanisms involved. These mechanisms are based both on direct physical interactions, which coordinate the cellular responses, and on the collective cell behaviour that generates an optimal environment for efficient directed migration. The recent studies have described how leader cells at the front of cell groups drive migration and have highlighted the importance of follower cells and cell-cell communication, both between followers and between follower and leader cells, to improve the efficiency of collective movement.
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Affiliation(s)
- Roberto Mayor
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Sandrine Etienne-Manneville
- Institut Pasteur, CNRS UMR 3691, Cell Polarity, Migration and Cancer Unit, 25 Rue du Dr Roux, 75724 Paris Cedex 15, France
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Ye D, Xie H, Hu B, Lin F. Endoderm convergence controls subduction of the myocardial precursors during heart-tube formation. Development 2015; 142:2928-40. [PMID: 26329600 PMCID: PMC10682956 DOI: 10.1242/dev.113944] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2014] [Accepted: 07/21/2015] [Indexed: 01/15/2023]
Abstract
Coordination between the endoderm and adjacent cardiac mesoderm is crucial for heart development. We previously showed that myocardial migration is promoted by convergent movement of the endoderm, which itself is controlled by the S1pr2/Gα13 signaling pathway, but it remains unclear how the movements of the two tissues is coordinated. Here, we image live and fixed embryos to follow these movements, revealing previously unappreciated details of strikingly complex and dynamic associations between the endoderm and myocardial precursors. We found that during segmentation the endoderm underwent three distinct phases of movement relative to the midline: rapid convergence, little convergence and slight expansion. During these periods, the myocardial cells exhibited different stage-dependent migratory modes: co-migration with the endoderm, movement from the dorsal to the ventral side of the endoderm (subduction) and migration independent of endoderm convergence. We also found that defects in S1pr2/Gα13-mediated endodermal convergence affected all three modes of myocardial cell migration, probably due to the disruption of fibronectin assembly around the myocardial cells and consequent disorganization of the myocardial epithelium. Moreover, we found that additional cell types within the anterior lateral plate mesoderm (ALPM) also underwent subduction, and that this movement likewise depended on endoderm convergence. Our study delineates for the first time the details of the intricate interplay between the endoderm and ALPM during embryogenesis, highlighting why endoderm movement is essential for heart development, and thus potential underpinnings of congenital heart disease.
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Affiliation(s)
- Ding Ye
- Department of Anatomy and Cell Biology, Carver College of Medicine, University of Iowa, 1-400 Bowen Science Building, 51 Newton Road, Iowa City, IA 52242-1109, USA
| | - Huaping Xie
- Department of Anatomy and Cell Biology, Carver College of Medicine, University of Iowa, 1-400 Bowen Science Building, 51 Newton Road, Iowa City, IA 52242-1109, USA
| | - Bo Hu
- Department of Anatomy and Cell Biology, Carver College of Medicine, University of Iowa, 1-400 Bowen Science Building, 51 Newton Road, Iowa City, IA 52242-1109, USA
| | - Fang Lin
- Department of Anatomy and Cell Biology, Carver College of Medicine, University of Iowa, 1-400 Bowen Science Building, 51 Newton Road, Iowa City, IA 52242-1109, USA
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Panza P, Maier J, Schmees C, Rothbauer U, Söllner C. Live imaging of endogenous protein dynamics in zebrafish using chromobodies. Development 2015; 142:1879-84. [PMID: 25968318 PMCID: PMC4440926 DOI: 10.1242/dev.118943] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Chromobodies are intracellular nanoprobes that combine the specificity of antibodies with the convenience of live fluorescence imaging in a flexible, DNA-encoded reagent. Here, we present the first application of this technique to an intact living vertebrate organism. We generated zebrafish lines expressing chromobodies that trace the major cytoskeletal component actin and the cell cycle marker PCNA with spatial and temporal specificity. Using these chromobodies, we captured full localization dynamics of the endogenous antigens in different cell types and at different stages of development. For the first time, the chromobody technology enables live imaging of endogenous subcellular structures in an animal, with the remarkable advantage of avoiding target protein overexpression or tagging. In combination with improved chromobody selection systems, we anticipate a rapid adaptation of this technique to new intracellular antigens and model organisms, allowing the faithful description of cellular and molecular processes in their dynamic state. SUMMARY: Chromobodies - small, intracellular fluorescent antibodies - are used to trace endogenous antigens, without the need for direct protein tagging, in zebrafish embryos.
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Affiliation(s)
- Paolo Panza
- Max-Planck-Institut für Entwicklungsbiologie, Abteilung Genetik, Spemannstraße 35, Tübingen 72076, Germany
| | - Julia Maier
- Naturwissenschaftliches und Medizinisches Institut der Universität Tübingen, Markwiesenstraße 55, Reutlingen 72770, Germany Pharmazeutische Biotechnologie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 8, Tübingen 72076, Germany
| | - Christian Schmees
- Naturwissenschaftliches und Medizinisches Institut der Universität Tübingen, Markwiesenstraße 55, Reutlingen 72770, Germany
| | - Ulrich Rothbauer
- Naturwissenschaftliches und Medizinisches Institut der Universität Tübingen, Markwiesenstraße 55, Reutlingen 72770, Germany Pharmazeutische Biotechnologie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 8, Tübingen 72076, Germany
| | - Christian Söllner
- Max-Planck-Institut für Entwicklungsbiologie, Abteilung Genetik, Spemannstraße 35, Tübingen 72076, Germany
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Abstract
Embryonic cell migration patterns are amazingly complex in the timing and spatial distribution of cells throughout the vertebrate landscape. However, advances in in vivo visualization, cell interrogation, and computational modeling are extracting critical features that underlie the mechanistic nature of these patterns. The focus of this review highlights recent advances in the study of the highly invasive neural crest cells and their migratory patterns during embryonic development. We discuss these advances within three major themes and include a description of computational models that have emerged to more rapidly integrate and test hypothetical mechanisms of neural crest migration. We conclude with technological advances that promise to reveal new insights and help translate results to human neural crest-related birth defects and metastatic cancer.
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Affiliation(s)
- Paul M. Kulesa
- Stowers Institute for Medical Research1000 E. 50 St, Kansas City, MO 64110USA
- Department of Anatomy and Cell Biology, University of Kansas School of MedicineKansas City, KS, 66160USA
| | - Rebecca McLennan
- Stowers Institute for Medical Research1000 E. 50 St, Kansas City, MO 64110USA
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Thomas ED, Cruz IA, Hailey DW, Raible DW. There and back again: development and regeneration of the zebrafish lateral line system. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2014; 4:1-16. [PMID: 25330982 DOI: 10.1002/wdev.160] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 07/10/2014] [Accepted: 08/24/2014] [Indexed: 12/23/2022]
Abstract
The zebrafish lateral line is a sensory system used to detect changes in water flow. It is comprised of clusters of mechanosensory hair cells called neuromasts. The lateral line is initially established by a migratory group of cells, called a primordium, that deposits neuromasts at stereotyped locations along the surface of the fish. Wnt, FGF, and Notch signaling are all important regulators of various aspects of lateral line development, from primordium migration to hair cell specification. As zebrafish age, the organization of the lateral line becomes more complex in order to accommodate the fish's increased size. This expansion is regulated by many of the same factors involved in the initial development. Furthermore, unlike mammalian hair cells, lateral line hair cells have the capacity to regenerate after damage. New hair cells arise from the proliferation and differentiation of surrounding support cells, and the molecular and cellular pathways regulating this are beginning to be elucidated. All in all, the zebrafish lateral line has proven to be an excellent model in which to study a diverse array of processes, including collective cell migration, cell polarity, cell fate, and regeneration.
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Affiliation(s)
- Eric D Thomas
- Graduate Program in Neurobiology and Behavior, University of Washington, Seattle, WA, USA; Department of Biological Structure, University of Washington, Seattle, WA, USA
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19
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Etienne-Manneville S. Neighborly relations during collective migration. Curr Opin Cell Biol 2014; 30:51-9. [PMID: 24997300 DOI: 10.1016/j.ceb.2014.06.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Revised: 06/04/2014] [Accepted: 06/11/2014] [Indexed: 10/25/2022]
Abstract
The collective migration of sheets, cohorts, chains or streams of cells contributes to embryogenesis, tissue remodeling and repair as well as to cancer invasion. The functional coordination between neighboring cells is at the heart of collective migration, during which cells migrate with a similar speed in an identical direction. Far from being the result of the simultaneous migration of isolated cells, collective migration relies on the intercellular communication between migrating cells. Although the mechanisms of cell coordination are far from being completely understood, accumulated evidence show that exchange of mechanical and chemical information by direct intercellular contacts and by soluble extracellular signals orchestrate the coordinated behavior of collectively migrating cells.
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Affiliation(s)
- Sandrine Etienne-Manneville
- Institut Pasteur - CNRS URA 2582, Cell Polarity, Migration and Cancer Unit, 25 rue du Dr Roux, 75724 Paris Cedex 15, France.
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20
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Spracklen AJ, Fagan TN, Lovander KE, Tootle TL. The pros and cons of common actin labeling tools for visualizing actin dynamics during Drosophila oogenesis. Dev Biol 2014; 393:209-226. [PMID: 24995797 DOI: 10.1016/j.ydbio.2014.06.022] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Revised: 04/04/2014] [Accepted: 06/17/2014] [Indexed: 10/25/2022]
Abstract
Dynamic remodeling of the actin cytoskeleton is required for both development and tissue homeostasis. While fixed image analysis has provided significant insight into such events, a complete understanding of cytoskeletal dynamics requires live imaging. Numerous tools for the live imaging of actin have been generated by fusing the actin-binding domain from an actin-interacting protein to a fluorescent protein. Here we comparatively assess the utility of three such tools--Utrophin, Lifeact, and F-tractin--for characterizing the actin remodeling events occurring within the germline-derived nurse cells during Drosophila mid-oogenesis or follicle development. Specifically, we used the UAS/GAL4 system to express these tools at different levels and in different cells, and analyzed these tools for effects on fertility, alterations in the actin cytoskeleton, and ability to label filamentous actin (F-actin) structures by both fixed and live imaging. While both Utrophin and Lifeact robustly label F-actin structures within the Drosophila germline, when strongly expressed they cause sterility and severe actin defects including cortical actin breakdown resulting in multi-nucleate nurse cells, early F-actin filament and aggregate formation during stage 9 (S9), and disorganized parallel actin filament bundles during stage 10B (S10B). However, by using a weaker germline GAL4 driver in combination with a higher temperature, Utrophin can label F-actin with minimal defects. Additionally, strong Utrophin expression within the germline causes F-actin formation in the nurse cell nuclei and germinal vesicle during mid-oogenesis. Similarly, Lifeact expression results in nuclear F-actin only within the germinal vesicle. F-tractin expresses at a lower level than the other two labeling tools, but labels cytoplasmic F-actin structures well without causing sterility or striking actin defects. Together these studies reveal how critical it is to evaluate the utility of each actin labeling tool within the tissue and cell type of interest in order to identify the tool that represents the best compromise between acceptable labeling and minimal disruption of the phenomenon being observed. In this case, we find that F-tractin, and perhaps Utrophin, when Utrophin expression levels are optimized to label efficiently without causing actin defects, can be used to study F-actin dynamics within the Drosophila nurse cells.
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Affiliation(s)
- Andrew J Spracklen
- Anatomy and Cell Biology Department, Carver College of Medicine, University of Iowa, 51 Newton Rd, Iowa City, IA 52242, USA
| | - Tiffany N Fagan
- Anatomy and Cell Biology Department, Carver College of Medicine, University of Iowa, 51 Newton Rd, Iowa City, IA 52242, USA
| | - Kaylee E Lovander
- Anatomy and Cell Biology Department, Carver College of Medicine, University of Iowa, 51 Newton Rd, Iowa City, IA 52242, USA
| | - Tina L Tootle
- Anatomy and Cell Biology Department, Carver College of Medicine, University of Iowa, 51 Newton Rd, Iowa City, IA 52242, USA.
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