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Chua XL, Tong CS, Su M, Xǔ XJ, Xiao S, Wu X, Wu M. Competition and synergy of Arp2/3 and formins in nucleating actin waves. Cell Rep 2024; 43:114423. [PMID: 38968072 DOI: 10.1016/j.celrep.2024.114423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Revised: 04/23/2024] [Accepted: 06/14/2024] [Indexed: 07/07/2024] Open
Abstract
Actin assembly and dynamics are crucial for maintaining cell structure and changing physiological states. The broad impact of actin on various cellular processes makes it challenging to dissect the specific role of actin regulatory proteins. Using actin waves that propagate on the cortex of mast cells as a model, we discovered that formins (FMNL1 and mDia3) are recruited before the Arp2/3 complex in actin waves. GTPase Cdc42 interactions drive FMNL1 oscillations, with active Cdc42 and the constitutively active mutant of FMNL1 capable of forming waves on the plasma membrane independently of actin waves. Additionally, the delayed recruitment of Arp2/3 antagonizes FMNL1 and active Cdc42. This antagonism is not due to competition for monomeric actin but rather for their common upstream regulator, active Cdc42, whose levels are negatively regulated by Arp2/3 via SHIP1 recruitment. Collectively, our study highlights the complex feedback loops in the dynamic control of the actin cytoskeletal network.
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Affiliation(s)
- Xiang Le Chua
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06510, USA; Department of Biological Sciences, Centre for Bioimaging Sciences, Singapore 117557, Singapore
| | - Chee San Tong
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06510, USA; Department of Biological Sciences, Centre for Bioimaging Sciences, Singapore 117557, Singapore
| | - Maohan Su
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06510, USA; Department of Biological Sciences, Centre for Bioimaging Sciences, Singapore 117557, Singapore; Mechanobiology Institute, National University of Singapore, Singapore 117411, Singapore
| | - X J Xǔ
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06510, USA; Department of Physics, Yale University, New Haven, CT 06511, USA
| | - Shengping Xiao
- Department of Biological Sciences, Centre for Bioimaging Sciences, Singapore 117557, Singapore
| | - Xudong Wu
- School of Life Sciences, Westlake University, Hangzhou 310024, China
| | - Min Wu
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06510, USA; Department of Biological Sciences, Centre for Bioimaging Sciences, Singapore 117557, Singapore; Mechanobiology Institute, National University of Singapore, Singapore 117411, Singapore.
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2
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Piszker W, Simunovic M. The fusion of physics and biology in early mammalian embryogenesis. Curr Top Dev Biol 2024; 160:31-64. [PMID: 38937030 DOI: 10.1016/bs.ctdb.2024.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/29/2024]
Abstract
Biomechanics in embryogenesis is a dynamic field intertwining the physical forces and biological processes that shape the first days of a mammalian embryo. From the first cell fate bifurcation during blastulation to the complex symmetry breaking and tissue remodeling in gastrulation, mechanical cues appear critical in cell fate decisions and tissue patterning. Recent strides in mouse and human embryo culture, stem cell modeling of mammalian embryos, and biomaterial design have shed light on the role of cellular forces, cell polarization, and the extracellular matrix in influencing cell differentiation and morphogenesis. This chapter highlights the essential functions of biophysical mechanisms in blastocyst formation, embryo implantation, and early gastrulation where the interplay between the cytoskeleton and extracellular matrix stiffness orchestrates the intricacies of embryogenesis and placenta specification. The advancement of in vitro models like blastoids, gastruloids, and other types of embryoids, has begun to faithfully recapitulate human development stages, offering new avenues for exploring the biophysical underpinnings of early development. The integration of synthetic biology and advanced biomaterials is enhancing the precision with which we can mimic and study these processes. Looking ahead, we emphasize the potential of CRISPR-mediated genomic perturbations coupled with live imaging to uncover new mechanosensitive pathways and the application of engineered biomaterials to fine-tune the mechanical conditions conducive to embryonic development. This synthesis not only bridges the gap between experimental models and in vivo conditions to advancing fundamental developmental biology of mammalian embryogenesis, but also sets the stage for leveraging biomechanical insights to inform regenerative medicine.
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Affiliation(s)
- Walter Piszker
- Department of Chemical Engineering, Fu Foundation School of Engineering and Applied Sciences, Columbia University, New York, NY, United States; Columbia Stem Cell Initiative, Columbia University Irving Medical Center, New York, NY, United States
| | - Mijo Simunovic
- Department of Chemical Engineering, Fu Foundation School of Engineering and Applied Sciences, Columbia University, New York, NY, United States; Columbia Stem Cell Initiative, Columbia University Irving Medical Center, New York, NY, United States; Department of Genetics and Development, Columbia Irving Medical Center, New York, NY, United States.
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3
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Firmin J, Ecker N, Rivet Danon D, Özgüç Ö, Barraud Lange V, Turlier H, Patrat C, Maître JL. Mechanics of human embryo compaction. Nature 2024; 629:646-651. [PMID: 38693259 DOI: 10.1038/s41586-024-07351-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 03/26/2024] [Indexed: 05/03/2024]
Abstract
The shaping of human embryos begins with compaction, during which cells come into close contact1,2. Assisted reproductive technology studies indicate that human embryos fail compaction primarily because of defective adhesion3,4. On the basis of our current understanding of animal morphogenesis5,6, other morphogenetic engines, such as cell contractility, could be involved in shaping human embryos. However, the molecular, cellular and physical mechanisms driving human embryo morphogenesis remain uncharacterized. Using micropipette aspiration on human embryos donated to research, we have mapped cell surface tensions during compaction. This shows a fourfold increase of tension at the cell-medium interface whereas cell-cell contacts keep a steady tension. Therefore, increased tension at the cell-medium interface drives human embryo compaction, which is qualitatively similar to compaction in mouse embryos7. Further comparison between human and mouse shows qualitatively similar but quantitively different mechanical strategies, with human embryos being mechanically least efficient. Inhibition of cell contractility and cell-cell adhesion in human embryos shows that, whereas both cellular processes are required for compaction, only contractility controls the surface tensions responsible for compaction. Cell contractility and cell-cell adhesion exhibit distinct mechanical signatures when faulty. Analysing the mechanical signature of naturally failing embryos, we find evidence that non-compacting or partially compacting embryos containing excluded cells have defective contractility. Together, our study shows that an evolutionarily conserved increase in cell contractility is required to generate the forces driving the first morphogenetic movement shaping the human body.
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Affiliation(s)
- Julie Firmin
- Institut Curie, Université PSL, CNRS UMR3215, INSERM U934, Paris, France
- Université de Paris, Paris, France
- Service de Biologie de la Reproduction - CECOS, Paris Centre Hospital, APHP centre, FHU Prema, Paris, France
| | - Nicolas Ecker
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Université PSL, FHU Prema, Paris, France
| | - Diane Rivet Danon
- Service de Biologie de la Reproduction - CECOS, Paris Centre Hospital, APHP centre, FHU Prema, Paris, France
| | - Özge Özgüç
- Institut Curie, Université PSL, CNRS UMR3215, INSERM U934, Paris, France
| | - Virginie Barraud Lange
- Service de Biologie de la Reproduction - CECOS, Paris Centre Hospital, APHP centre, FHU Prema, Paris, France
- Institut Cochin, Université de Paris, CNRS UMR1016, Paris, France
| | - Hervé Turlier
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Université PSL, FHU Prema, Paris, France
| | - Catherine Patrat
- Service de Biologie de la Reproduction - CECOS, Paris Centre Hospital, APHP centre, FHU Prema, Paris, France
- Institut Cochin, Université de Paris, CNRS UMR1016, Paris, France
| | - Jean-Léon Maître
- Institut Curie, Université PSL, CNRS UMR3215, INSERM U934, Paris, France.
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4
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Nikalayevich E, Letort G, de Labbey G, Todisco E, Shihabi A, Turlier H, Voituriez R, Yahiatene M, Pollet-Villard X, Innocenti M, Schuh M, Terret ME, Verlhac MH. Aberrant cortex contractions impact mammalian oocyte quality. Dev Cell 2024; 59:841-852.e7. [PMID: 38387459 DOI: 10.1016/j.devcel.2024.01.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 12/18/2023] [Accepted: 01/26/2024] [Indexed: 02/24/2024]
Abstract
The cortex controls cell shape. In mouse oocytes, the cortex thickens in an Arp2/3-complex-dependent manner, ensuring chromosome positioning and segregation. Surprisingly, we identify that mouse oocytes lacking the Arp2/3 complex undergo cortical actin remodeling upon division, followed by cortical contractions that are unprecedented in mammalian oocytes. Using genetics, imaging, and machine learning, we show that these contractions stir the cytoplasm, resulting in impaired organelle organization and activity. Oocyte capacity to avoid polyspermy is impacted, leading to a reduced female fertility. We could diminish contractions and rescue cytoplasmic anomalies. Similar contractions were observed in human oocytes collected as byproducts during IVF (in vitro fertilization) procedures. These contractions correlate with increased cytoplasmic motion, but not with defects in spindle assembly or aneuploidy in mice or humans. Our study highlights a multiscale effect connecting cortical F-actin, contractions, and cytoplasmic organization and affecting oocyte quality, with implications for female fertility.
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Affiliation(s)
- Elvira Nikalayevich
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, Université PSL, CNRS, INSERM, 75005 Paris, France
| | - Gaëlle Letort
- Department of Developmental and Stem Cell Biology, Institut Pasteur, CNRS UMR 3738, Université Paris Cité, 25 rue du Dr. Roux, 75015 Paris, France
| | - Ghislain de Labbey
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, Université PSL, CNRS, INSERM, 75005 Paris, France
| | - Elena Todisco
- Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Anastasia Shihabi
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, Université PSL, CNRS, INSERM, 75005 Paris, France
| | - Hervé Turlier
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, Université PSL, CNRS, INSERM, 75005 Paris, France
| | - Raphaël Voituriez
- Laboratoire de Physique Théorique de la Matière Condensée (LPTMC), Laboratoire Jean Perrin, CNRS, Sorbonne Université, Paris, France
| | - Mohamed Yahiatene
- Centre Assistance Médicale à la Procréation Nataliance, Groupe Mlab, Pôle Santé Oréliance, Saran, France
| | - Xavier Pollet-Villard
- Centre Assistance Médicale à la Procréation Nataliance, Groupe Mlab, Pôle Santé Oréliance, Saran, France
| | - Metello Innocenti
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, 20126 Milan, Italy
| | - Melina Schuh
- Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Marie-Emilie Terret
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, Université PSL, CNRS, INSERM, 75005 Paris, France.
| | - Marie-Hélène Verlhac
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, Université PSL, CNRS, INSERM, 75005 Paris, France.
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Fluks M, Collier R, Walewska A, Bruce AW, Ajduk A. How great thou ART: biomechanical properties of oocytes and embryos as indicators of quality in assisted reproductive technologies. Front Cell Dev Biol 2024; 12:1342905. [PMID: 38425501 PMCID: PMC10902081 DOI: 10.3389/fcell.2024.1342905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Accepted: 02/01/2024] [Indexed: 03/02/2024] Open
Abstract
Assisted Reproductive Technologies (ART) have revolutionized infertility treatment and animal breeding, but their success largely depends on selecting high-quality oocytes for fertilization and embryos for transfer. During preimplantation development, embryos undergo complex morphogenetic processes, such as compaction and cavitation, driven by cellular forces dependent on cytoskeletal dynamics and cell-cell interactions. These processes are pivotal in dictating an embryo's capacity to implant and progress to full-term development. Hence, a comprehensive grasp of the biomechanical attributes characterizing healthy oocytes and embryos is essential for selecting those with higher developmental potential. Various noninvasive techniques have emerged as valuable tools for assessing biomechanical properties without disturbing the oocyte or embryo physiological state, including morphokinetics, analysis of cytoplasmic movement velocity, or quantification of cortical tension and elasticity using microaspiration. By shedding light on the cytoskeletal processes involved in chromosome segregation, cytokinesis, cellular trafficking, and cell adhesion, underlying oogenesis, and embryonic development, this review explores the significance of embryo biomechanics in ART and its potential implications for improving clinical IVF outcomes, offering valuable insights and research directions to enhance oocyte and embryo selection procedures.
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Affiliation(s)
- Monika Fluks
- Department of Embryology, Institute of Developmental Biology and Biomedical Sciences, Faculty of Biology, University of Warsaw, Warsaw, Poland
- Department of Molecular Biology and Genetics, Faculty of Science, University of South Bohemia in České Budějovice, České Budějovice, Czechia
| | - Rebecca Collier
- Department of Molecular Biology and Genetics, Faculty of Science, University of South Bohemia in České Budějovice, České Budějovice, Czechia
| | - Agnieszka Walewska
- Department of Embryology, Institute of Developmental Biology and Biomedical Sciences, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Alexander W. Bruce
- Department of Molecular Biology and Genetics, Faculty of Science, University of South Bohemia in České Budějovice, České Budějovice, Czechia
| | - Anna Ajduk
- Department of Embryology, Institute of Developmental Biology and Biomedical Sciences, Faculty of Biology, University of Warsaw, Warsaw, Poland
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Pelzer D, de Plater L, Bradbury P, Eichmuller A, Bourdais A, Halet G, Maître J. Cell fragmentation in mouse preimplantation embryos induced by ectopic activation of the polar body extrusion pathway. EMBO J 2023; 42:e114415. [PMID: 37427462 PMCID: PMC10476277 DOI: 10.15252/embj.2023114415] [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: 05/02/2023] [Revised: 06/13/2023] [Accepted: 06/22/2023] [Indexed: 07/11/2023] Open
Abstract
Cell fragmentation is commonly observed in human preimplantation embryos and is associated with poor prognosis during assisted reproductive technology (ART) procedures. However, the mechanisms leading to cell fragmentation remain largely unknown. Here, light sheet microscopy imaging of mouse embryos reveals that inefficient chromosome separation due to spindle defects, caused by dysfunctional molecular motors Myo1c or dynein, leads to fragmentation during mitosis. Extended exposure of the cell cortex to chromosomes locally triggers actomyosin contractility and pinches off cell fragments. This process is reminiscent of meiosis, during which small GTPase-mediated signals from chromosomes coordinate polar body extrusion (PBE) by actomyosin contraction. By interfering with the signals driving PBE, we find that this meiotic signaling pathway remains active during cleavage stages and is both required and sufficient to trigger fragmentation. Together, we find that fragmentation happens in mitosis after ectopic activation of actomyosin contractility by signals emanating from DNA, similar to those observed during meiosis. Our study uncovers the mechanisms underlying fragmentation in preimplantation embryos and, more generally, offers insight into the regulation of mitosis during the maternal-zygotic transition.
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Affiliation(s)
- Diane Pelzer
- Institut CuriePSL Research University, CNRS UMR 3215, INSERM U934ParisFrance
| | - Ludmilla de Plater
- Institut CuriePSL Research University, CNRS UMR 3215, INSERM U934ParisFrance
| | - Peta Bradbury
- Institut CuriePSL Research University, CNRS UMR 3215, INSERM U934ParisFrance
| | - Adrien Eichmuller
- Institut CuriePSL Research University, CNRS UMR 3215, INSERM U934ParisFrance
| | - Anne Bourdais
- Institut de Génétique et Développement de RennesUniversité de Rennes, CNRS UMR 6290RennesFrance
| | - Guillaume Halet
- Institut de Génétique et Développement de RennesUniversité de Rennes, CNRS UMR 6290RennesFrance
| | - Jean‐Léon Maître
- Institut CuriePSL Research University, CNRS UMR 3215, INSERM U934ParisFrance
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7
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Xu WT, Shi LL, Xu J, Qian H, Zhou H, Wang LH. Ezrin expression in female reproductive tissues: A review of regulation and pathophysiological implications. Front Cell Dev Biol 2023; 11:1125881. [PMID: 36968198 PMCID: PMC10030596 DOI: 10.3389/fcell.2023.1125881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Accepted: 02/27/2023] [Indexed: 03/29/2023] Open
Abstract
Ezrin, a plasma membrane-microfilament linker, is a cytoskeletal organizer involved in many cellular activities by binding to the membrane protein-ezrin-cytoskeletal protein complex and regulating downstream signal transduction. Increasing evidence demonstrates that ezrin plays an important role in regulating cell polarity, proliferation and invasion. In this study, we analyzed the effects of ezrin on oocytes, follicle development, embryo development and embryo implantation. We reviewed the recent studies on the modalities of ezrin regulation and its involvement in the biological processes of female reproductive physiology and summarized the current research advances in ezrin inhibitors. These studies will provide new strategies and insights for the treatment of diseases.
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Affiliation(s)
- Wen-Ting Xu
- Department of Reproduction, Zhangjiagang TCM Hospital Affiliated to Nanjing University of Chinese Medicine, Zhangjiagang, Suzhou, Jiangsu, China
| | - Ling-Li Shi
- Department of Reproduction, Zhangjiagang TCM Hospital Affiliated to Nanjing University of Chinese Medicine, Zhangjiagang, Suzhou, Jiangsu, China
| | - Jie Xu
- Translational Medical Innovation Center, Zhangjiagang TCM Hospital Affiliated to Nanjing University of Chinese Medicine, Zhangjiagang, Suzhou, Jiangsu, China
| | - Haiqing Qian
- Department of Reproduction, Zhangjiagang TCM Hospital Affiliated to Nanjing University of Chinese Medicine, Zhangjiagang, Suzhou, Jiangsu, China
| | - Huifang Zhou
- Department of Gynaecology, Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing, China
- *Correspondence: Huifang Zhou, ; Li-Hong Wang,
| | - Li-Hong Wang
- Department of Reproduction, Zhangjiagang TCM Hospital Affiliated to Nanjing University of Chinese Medicine, Zhangjiagang, Suzhou, Jiangsu, China
- *Correspondence: Huifang Zhou, ; Li-Hong Wang,
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Barone V, Lyons DC. Live imaging of echinoderm embryos to illuminate evo-devo. Front Cell Dev Biol 2022; 10:1007775. [PMID: 36187474 PMCID: PMC9521734 DOI: 10.3389/fcell.2022.1007775] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Accepted: 08/24/2022] [Indexed: 11/16/2022] Open
Abstract
Echinoderm embryos have been model systems for cell and developmental biology for over 150 years, in good part because of their optical clarity. Discoveries that shaped our understanding of fertilization, cell division and cell differentiation were only possible because of the transparency of sea urchin eggs and embryos, which allowed direct observations of intracellular structures. More recently, live imaging of sea urchin embryos, coupled with fluorescence microscopy, has proven pivotal to uncovering mechanisms of epithelial to mesenchymal transition, cell migration and gastrulation. However, live imaging has mainly been performed on sea urchin embryos, while echinoderms include numerous experimentally tractable species that present interesting variation in key aspects of morphogenesis, including differences in embryo compaction and mechanisms of blastula formation. The study of such variation would allow us not only to understand how tissues are formed in echinoderms, but also to identify which changes in cell shape, cell-matrix and cell-cell contact formation are more likely to result in evolution of new embryonic shapes. Here we argue that adapting live imaging techniques to more echinoderm species will be fundamental to exploit such an evolutionary approach to the study of morphogenesis, as it will allow measuring differences in dynamic cellular behaviors - such as changes in cell shape and cell adhesion - between species. We briefly review existing methods for live imaging of echinoderm embryos and describe in detail how we adapted those methods to allow long-term live imaging of several species, namely the sea urchin Lytechinus pictus and the sea stars Patiria miniata and Patiriella regularis. We outline procedures to successfully label, mount and image early embryos for 10–16 h, from cleavage stages to early blastula. We show that data obtained with these methods allows 3D segmentation and tracking of individual cells over time, the first step to analyze how cell shape and cell contact differ among species. The methods presented here can be easily adopted by most cell and developmental biology laboratories and adapted to successfully image early embryos of additional species, therefore broadening our understanding of the evolution of morphogenesis.
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Canales Coutiño B, Mayor R. Neural crest mechanosensors: Seeing old proteins in a new light. Dev Cell 2022; 57:1792-1801. [PMID: 35901790 DOI: 10.1016/j.devcel.2022.07.005] [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: 03/31/2022] [Revised: 05/26/2022] [Accepted: 07/05/2022] [Indexed: 11/25/2022]
Abstract
Mechanical forces exerted on neural crest cells control their collective migration and differentiation. This perspective discusses our current understanding of neural crest mechanotransduction during cell migration and differentiation. Additionally, we describe proteins that have mechanosensitive functions in other systems, such as mechanosensitive G-protein-coupled receptors, mechanosensitive ion channels, cell-cell adhesion, and cell-matrix-interacting proteins, and highlight that these same proteins have in the past been studied in neural crest development from a purely signaling point of view. We propose that future studies elucidate the mechanosensitive functions these receptors may play in neural crest development and integrate this with their known molecular role.
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Affiliation(s)
- Brenda Canales Coutiño
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Roberto Mayor
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK.
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