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Rosa-Birriel C, Malin J, Hatini V. Medioapical contractile pulses coordinated between cells regulate Drosophila eye morphogenesis. J Cell Biol 2024; 223:e202304041. [PMID: 38126997 PMCID: PMC10737437 DOI: 10.1083/jcb.202304041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 10/31/2023] [Accepted: 12/07/2023] [Indexed: 12/23/2023] Open
Abstract
Lattice cells (LCs) in the developing Drosophila retina change shape before attaining final form. Previously, we showed that repeated contraction and expansion of apical cell contacts affect these dynamics. Here, we describe another factor, the assembly of a Rho1-dependent medioapical actomyosin ring formed by nodes linked by filaments that contract the apical cell area. Cell area contraction alternates with relaxation, generating pulsatile changes in cell area that exert force on neighboring LCs. Moreover, Rho1 signaling is sensitive to mechanical changes, becoming active when tension decreases and cells expand, while the negative regulator RhoGAP71E accumulates when tension increases and cells contract. This results in cycles of cell area contraction and relaxation that are reciprocally synchronized between adjacent LCs. Thus, mechanically sensitive Rho1 signaling controls pulsatile medioapical actomyosin contraction and coordinates cell behavior across the epithelium. Disrupting the kinetics of pulsing can lead to developmental errors, suggesting this process controls cell shape and tissue integrity during epithelial morphogenesis of the retina.
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Affiliation(s)
- Christian Rosa-Birriel
- Department of Developmental, Molecular and Chemical Biology, Program in Cell, Molecular and Developmental Biology, Program in Genetics, and Program in Pharmacology and Experimental Therapeutics, Tufts University School of Medicine, Boston, MA, USA
| | - Jacob Malin
- Department of Developmental, Molecular and Chemical Biology, Program in Cell, Molecular and Developmental Biology, Program in Genetics, and Program in Pharmacology and Experimental Therapeutics, Tufts University School of Medicine, Boston, MA, USA
| | - Victor Hatini
- Department of Developmental, Molecular and Chemical Biology, Program in Cell, Molecular and Developmental Biology, Program in Genetics, and Program in Pharmacology and Experimental Therapeutics, Tufts University School of Medicine, Boston, MA, USA
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2
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Gazsó-Gerhát G, Gombos R, Tóth K, Kaltenecker P, Szikora S, Bíró J, Csapó E, Asztalos Z, Mihály J. FRL and DAAM are required for lateral adhesion of interommatidial cells and patterning of the retinal floor. Development 2023; 150:dev201713. [PMID: 37997920 PMCID: PMC10690107 DOI: 10.1242/dev.201713] [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: 02/17/2023] [Accepted: 10/17/2023] [Indexed: 11/25/2023]
Abstract
Optical insulation of the unit eyes (ommatidia) is an important prerequisite of precise sight with compound eyes. Separation of the ommatidia is ensured by pigment cells that organize into a hexagonal lattice in the Drosophila eye, forming thin walls between the facets. Cell adhesion, mediated by apically and latero-basally located junctional complexes, is crucial for stable attachment of these cells to each other and the basal lamina. Whereas former studies have focused on the formation and remodelling of the cellular connections at the apical region, here, we report a specific alteration of the lateral adhesion of the lattice cells, leaving the apical junctions largely unaffected. We found that DAAM and FRL, two formin-type cytoskeleton regulatory proteins, play redundant roles in lateral adhesion of the interommatidial cells and patterning of the retinal floor. We show that formin-dependent cortical actin assembly is crucial for latero-basal sealing of the ommatidial lattice. We expect that the investigation of these previously unreported eye phenotypes will pave the way toward a better understanding of the three-dimensional aspects of compound eye development.
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Affiliation(s)
- Gabriella Gazsó-Gerhát
- Institute of Genetics, HUN-REN Biological Research Centre, Temesvári krt. 62, Szeged H-6726, Hungary
- Doctoral School in Biology, Faculty of Science and Informatics, University of Szeged, Szeged H-6726, Hungary
| | - Rita Gombos
- Institute of Genetics, HUN-REN Biological Research Centre, Temesvári krt. 62, Szeged H-6726, Hungary
| | - Krisztina Tóth
- Institute of Genetics, HUN-REN Biological Research Centre, Temesvári krt. 62, Szeged H-6726, Hungary
| | - Péter Kaltenecker
- Institute of Genetics, HUN-REN Biological Research Centre, Temesvári krt. 62, Szeged H-6726, Hungary
| | - Szilárd Szikora
- Institute of Genetics, HUN-REN Biological Research Centre, Temesvári krt. 62, Szeged H-6726, Hungary
| | - Judit Bíró
- Aktogen Hungary Ltd., Szeged H-6726, Hungary
| | - Enikő Csapó
- Aktogen Hungary Ltd., Szeged H-6726, Hungary
| | - Zoltán Asztalos
- Institute of Biochemistry, HUN-REN Biological Research Centre, Szeged H-6726, Hungary
| | - József Mihály
- Institute of Genetics, HUN-REN Biological Research Centre, Temesvári krt. 62, Szeged H-6726, Hungary
- Department of Genetics, University of Szeged, Szeged H-6726, Hungary
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3
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Rosa C, Malin J, Hatini V. Medioapical contractile pulses coordinated between cells regulate Drosophila eye morphogenesis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.17.529936. [PMID: 36993651 PMCID: PMC10055172 DOI: 10.1101/2023.03.17.529936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Lattice cells (LCs) in the developing Drosophila retina constantly move and change shape before attaining final forms. Previously we showed that repeated contraction and expansion of apical cell contacts affect these dynamics. Here we describe a second contributing factor, the assembly of a medioapical actomyosin ring composed of nodes linked by filaments that attract each other, fuse, and contract the LCs' apical area. This medioapical actomyosin network is dependent on Rho1 and its known effectors. Apical cell area contraction alternates with relaxation, generating pulsatile changes in apical cell area. Strikingly, cycles of contraction and relaxation of cell area are reciprocally synchronized between adjacent LCs. Further, in a genetic screen, we identified RhoGEF2 as an activator of these Rho1 functions and RhoGAP71E/C-GAP as an inhibitor. Thus, Rho1 signaling regulates pulsatile medioapical actomyosin contraction exerting force on neighboring cells, coordinating cell behavior across the epithelium. This ultimately serves to control cell shape and maintain tissue integrity during epithelial morphogenesis of the retina.
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Cessna H, Baritaki S, Zaravinos A, Bonavida B. The Role of RKIP in the Regulation of EMT in the Tumor Microenvironment. Cancers (Basel) 2022; 14:cancers14194596. [PMID: 36230521 PMCID: PMC9559516 DOI: 10.3390/cancers14194596] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 09/21/2022] [Accepted: 09/21/2022] [Indexed: 12/03/2022] Open
Abstract
Simple Summary Raf kinase inhibitor protein (RKIP) expression in cancer cells is significantly reduced and promoting cancer cells growth and invasiveness. Overexpresssion of RKIP has been reported to mediate pleiotropic anti-cancer activities including the inhibition of survival signaling pathways, sensitization to cell death by cytotoxic drugs, inhibition of invasion, EMT and metastasis. The molecular mechanism by which RKIP inhibits EMT is not clear. In this review, we have examined how RKIP inhibits the selected EMT gene products (Snail, vimentin, N-cadherin, laminin alpha) and found that it involves signaling cross-talks between RKIP and each of the EMT gene products. These findings were validated by bioinformatic analyses demonstrating in various human cancers a negative correlation between the expression of RKIP and the expression of the EMT gene products. These findings suggest that targeting RKIP induction in cancer cells will result in multiple hits by inhibiting tumor growth, metastasis and reversal of chemo-immuno resistance. Abstract The Raf Kinase Inhibitor Protein (RKIP) is a unique gene product that directly inhibits the Raf/Mek/Erk and NF-kB pathways in cancer cells and resulting in the inhibition of cell proliferation, viability, EMT, and metastasis. Additionally, RKIP is involved in the regulation of cancer cell resistance to both chemotherapy and immunotherapy. The low expression of RKIP expression in many cancer types is responsible, in part, for the pathogenesis of cancer and its multiple properties. The inhibition of EMT and metastasis by RKIP led to its classification as a tumor suppressor. However, the mechanism by which RKIP mediates its inhibitory effects on EMT and metastases was not clear. We have proposed that one mechanism involves the negative regulation by RKIP of the expression of various gene products that mediate the mesenchymal phenotype as well as the positive regulation of gene products that mediate the epithelial phenotype via signaling cross talks between RKIP and each gene product. We examined several EMT mesenchymal gene products such as Snail, vimentin, N-cadherin, laminin and EPCAM and epithelial gene products such as E-cadherin and laminin. We have found that indeed these negative and positive correlations were detected in the signaling cross-talks. In addition, we have also examined bioinformatic data sets on different human cancers and the findings corroborated, in large part, the findings observed in the signaling cross-talks with few exceptions in some cancer types. The overall findings support the underlying mechanism by which the tumor suppressor RKIP regulates the expression of gene products involved in EMT and metastasis. Hence, the development of agent that can selectively induce RKIP expression in cancers with low expressions should result in the activation of the pleiotropic anti-cancer activities of RKIP and resulting in multiple effects including inhibition of tumor cell proliferation, EMT, metastasis and sensitization of resistant tumor cells to respond to both chemotherapeutics and immunotherapeutics.
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Affiliation(s)
- Hannah Cessna
- Department of Microbiology, Immunology & Molecular Genetics, David Geffen School of Medicine, Jonsson Comprehensive Cancer Center, University of California at Los Angeles, Los Angeles, CA 90095, USA
| | - Stavroula Baritaki
- Laboratory of Experimental Oncology, Division of Surgery, School of Medicine, University of Crete, 71003 Heraklion, Greece
| | - Apostolos Zaravinos
- Department of Life Sciences, School of Sciences, European University Cyprus, Nicosia 2404, Cyprus
- Basic and Translational Cancer Research Center (BTCRC), Cancer Genetics, Genomics and Systems Biology Laboratory, Nicosia 1516, Cyprus
| | - Benjamin Bonavida
- Department of Microbiology, Immunology & Molecular Genetics, David Geffen School of Medicine, Jonsson Comprehensive Cancer Center, University of California at Los Angeles, Los Angeles, CA 90095, USA
- Correspondence:
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Malin J, Rosa Birriel C, Astigarraga S, Treisman JE, Hatini V. Sidekick dynamically rebalances contractile and protrusive forces to control tissue morphogenesis. J Cell Biol 2022; 221:e202107035. [PMID: 35258563 PMCID: PMC8908789 DOI: 10.1083/jcb.202107035] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 12/28/2021] [Accepted: 02/07/2022] [Indexed: 12/19/2022] Open
Abstract
Contractile actomyosin and protrusive branched F-actin networks interact in a dynamic balance, repeatedly contracting and expanding apical cell contacts to organize the epithelium of the developing fly retina. Previously we showed that the immunoglobulin superfamily protein Sidekick (Sdk) contributes to contraction by recruiting the actin binding protein Polychaetoid (Pyd) to vertices. Here we show that as tension increases during contraction, Sdk progressively accumulates at vertices, where it toggles to recruit the WAVE regulatory complex (WRC) to promote actin branching and protrusion. Sdk alternately interacts with the WRC and Pyd using the same C-terminal motif. With increasing protrusion, levels of Sdk and the WRC decrease at vertices while levels of Pyd increase paving the way for another round of contraction. Thus, by virtue of dynamic association with vertices and interchangeable associations with contractile and protrusive effectors, Sdk is central to controlling the balance between contraction and expansion that shapes this epithelium.
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Affiliation(s)
- Jacob Malin
- Department of Developmental, Molecular & Chemical Biology, Program in Cell, Molecular and Developmental Biology and Program in Genetics, Tufts University School of Medicine, Boston, MA
| | - Christian Rosa Birriel
- Department of Developmental, Molecular & Chemical Biology, Program in Cell, Molecular and Developmental Biology and Program in Genetics, Tufts University School of Medicine, Boston, MA
| | - Sergio Astigarraga
- Skirball Institute for Biomolecular Medicine, New York, NY
- Department of Cell Biology, New York University School of Medicine, New York, NY
| | - Jessica E. Treisman
- Skirball Institute for Biomolecular Medicine, New York, NY
- Department of Cell Biology, New York University School of Medicine, New York, NY
| | - Victor Hatini
- Department of Developmental, Molecular & Chemical Biology, Program in Cell, Molecular and Developmental Biology and Program in Genetics, Tufts University School of Medicine, Boston, MA
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Belyaeva V, Wachner S, Gyoergy A, Emtenani S, Gridchyn I, Akhmanova M, Linder M, Roblek M, Sibilia M, Siekhaus D. Fos regulates macrophage infiltration against surrounding tissue resistance by a cortical actin-based mechanism in Drosophila. PLoS Biol 2022; 20:e3001494. [PMID: 34990456 PMCID: PMC8735623 DOI: 10.1371/journal.pbio.3001494] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Accepted: 11/25/2021] [Indexed: 12/20/2022] Open
Abstract
The infiltration of immune cells into tissues underlies the establishment of tissue-resident macrophages and responses to infections and tumors. Yet the mechanisms immune cells utilize to negotiate tissue barriers in living organisms are not well understood, and a role for cortical actin has not been examined. Here, we find that the tissue invasion of Drosophila macrophages, also known as plasmatocytes or hemocytes, utilizes enhanced cortical F-actin levels stimulated by the Drosophila member of the fos proto oncogene transcription factor family (Dfos, Kayak). RNA sequencing analysis and live imaging show that Dfos enhances F-actin levels around the entire macrophage surface by increasing mRNA levels of the membrane spanning molecular scaffold tetraspanin TM4SF, and the actin cross-linking filamin Cheerio, which are themselves required for invasion. Both the filamin and the tetraspanin enhance the cortical activity of Rho1 and the formin Diaphanous and thus the assembly of cortical actin, which is a critical function since expressing a dominant active form of Diaphanous can rescue the Dfos macrophage invasion defect. In vivo imaging shows that Dfos enhances the efficiency of the initial phases of macrophage tissue entry. Genetic evidence argues that this Dfos-induced program in macrophages counteracts the constraint produced by the tension of surrounding tissues and buffers the properties of the macrophage nucleus from affecting tissue entry. We thus identify strengthening the cortical actin cytoskeleton through Dfos as a key process allowing efficient forward movement of an immune cell into surrounding tissues. The infiltration of immune cells into tissue underlies the establishment of tissue-resident macrophages, and responses to infections and tumors, but how do they overcome tissue barriers? This study shows that macrophages upregulate the proto-oncogene Fos, increasing the density and crosslinking of cortical actin, thereby counteracting the tension of surrounding tissues and protecting the macrophage nucleus.
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Affiliation(s)
- Vera Belyaeva
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Stephanie Wachner
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Attila Gyoergy
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Shamsi Emtenani
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Igor Gridchyn
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Maria Akhmanova
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Markus Linder
- Institute of Cancer Research, Department of Medicine 1, Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria
| | - Marko Roblek
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Maria Sibilia
- Institute of Cancer Research, Department of Medicine 1, Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria
| | - Daria Siekhaus
- Institute of Science and Technology Austria, Klosterneuburg, Austria
- * E-mail:
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7
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Ready DF, Chang HC. Calcium waves facilitate and coordinate the contraction of endfeet actin stress fibers in Drosophila interommatidial cells. Development 2021; 148:272616. [PMID: 34698814 DOI: 10.1242/dev.199700] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 10/18/2021] [Indexed: 01/04/2023]
Abstract
Actomyosin contraction shapes the Drosophila eye's panoramic view. The convex curvature of the retinal epithelium, organized in ∼800 close-packed ommatidia, depends upon a fourfold condensation of the retinal floor mediated by contraction of actin stress fibers in the endfeet of interommatidial cells (IOCs). How these tensile forces are coordinated is not known. Here, we discover a novel phenomenon: Ca2+ waves regularly propagate across the IOC network in pupal and adult eyes. Genetic evidence demonstrates that IOC waves are independent of phototransduction, but require inositol 1,4,5-triphosphate receptor (IP3R), suggesting these waves are mediated by Ca2+ releases from ER stores. Removal of IP3R disrupts stress fibers in IOC endfeet and increases the basal retinal surface by ∼40%, linking IOC waves to facilitating stress fiber contraction and floor morphogenesis. Further, IP3R loss disrupts the organization of a collagen IV network underneath the IOC endfeet, implicating ECM and its interaction with stress fibers in eye morphogenesis. We propose that coordinated cytosolic Ca2+ increases in IOC waves promote stress fiber contractions, ensuring an organized application of the planar tensile forces that condense the retinal floor.
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Affiliation(s)
- Donald F Ready
- Department of Biological Sciences, Purdue University, 915 West State Street, West Lafayette, Indiana 47907-2054, USA
| | - Henry C Chang
- Department of Biological Sciences, Purdue University, 915 West State Street, West Lafayette, Indiana 47907-2054, USA
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Deng H, Yang L, Wen P, Lei H, Blount P, Pan D. Spectrin couples cell shape, cortical tension, and Hippo signaling in retinal epithelial morphogenesis. J Cell Biol 2020; 219:133846. [PMID: 32328630 PMCID: PMC7147103 DOI: 10.1083/jcb.201907018] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 11/26/2019] [Accepted: 01/17/2020] [Indexed: 01/05/2023] Open
Abstract
Although extracellular force has a profound effect on cell shape, cytoskeleton tension, and cell proliferation through the Hippo signaling effector Yki/YAP/TAZ, how intracellular force regulates these processes remains poorly understood. Here, we report an essential role for spectrin in specifying cell shape by transmitting intracellular actomyosin force to cell membrane. While activation of myosin II in Drosophila melanogaster pupal retina leads to increased cortical tension, apical constriction, and Yki-mediated hyperplasia, spectrin mutant cells, despite showing myosin II activation and Yki-mediated hyperplasia, paradoxically display decreased cortical tension and expanded apical area. Mechanistically, we show that spectrin is required for tethering cortical F-actin to cell membrane domains outside the adherens junctions (AJs). Thus, in the absence of spectrin, the weakened attachment of cortical F-actin to plasma membrane results in a failure to transmit actomyosin force to cell membrane, causing an expansion of apical surfaces. These results uncover an essential mechanism that couples cell shape, cortical tension, and Hippo signaling and highlight the importance of non–AJ membrane domains in dictating cell shape in tissue morphogenesis.
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Affiliation(s)
- Hua Deng
- Department of Physiology, Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX
| | - Limin Yang
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX
| | - Pei Wen
- Department of Physiology, Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX
| | - Huiyan Lei
- Department of Physiology, Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX
| | - Paul Blount
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX
| | - Duojia Pan
- Department of Physiology, Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX
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9
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Díaz-Díaz C, Baonza G, Martín-Belmonte F. The vertebrate epithelial apical junctional complex: Dynamic interplay between Rho GTPase activity and cell polarization processes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183398. [DOI: 10.1016/j.bbamem.2020.183398] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 06/05/2020] [Accepted: 06/11/2020] [Indexed: 12/31/2022]
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10
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Zhang X, Bandyopadhyay S, Araujo LP, Tong K, Flores J, Laubitz D, Zhao Y, Yap G, Wang J, Zou Q, Ferraris R, Zhang L, Hu W, Bonder EM, Kiela PR, Coffey R, Verzi MP, Ivanov II, Gao N. Elevating EGFR-MAPK program by a nonconventional Cdc42 enhances intestinal epithelial survival and regeneration. JCI Insight 2020; 5:135923. [PMID: 32686657 PMCID: PMC7455142 DOI: 10.1172/jci.insight.135923] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 07/09/2020] [Indexed: 01/05/2023] Open
Abstract
The regulatory mechanisms enabling the intestinal epithelium to maintain a high degree of regenerative capacity during mucosal injury remain unclear. Ex vivo survival and clonogenicity of intestinal stem cells (ISCs) strictly required growth response mediated by cell division control 42 (Cdc42) and Cdc42-deficient enteroids to undergo rapid apoptosis. Mechanistically, Cdc42 engaging with EGFR was required for EGF-stimulated, receptor-mediated endocytosis and sufficient to promote MAPK signaling. Proteomics and kinase analysis revealed that a physiologically, but nonconventionally, spliced Cdc42 variant 2 (V2) exhibited stronger MAPK-activating capability. Human CDC42-V2 is transcriptionally elevated in some colon tumor tissues. Accordingly, mice engineered to overexpress Cdc42-V2 in intestinal epithelium showed elevated MAPK signaling, enhanced regeneration, and reduced mucosal damage in response to irradiation. Overproducing Cdc42-V2 specifically in mouse ISCs enhanced intestinal regeneration following injury. Thus, the intrinsic Cdc42-MAPK program is required for intestinal epithelial regeneration, and elevating this signaling cascade is capable of initiating protection from genotoxic injury.
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Affiliation(s)
- Xiao Zhang
- Department of Biological Sciences, Division of Life Sciences, School of Arts and Sciences, Rutgers University, Newark, New Jersey, USA
| | - Sheila Bandyopadhyay
- Department of Biological Sciences, Division of Life Sciences, School of Arts and Sciences, Rutgers University, Newark, New Jersey, USA
| | - Leandro Pires Araujo
- Department of Microbiology and Immunology, Vagelos College of Physicians and Surgeons, Columbia University, New York, New York, USA
| | - Kevin Tong
- Department of Genetics, Division of Life Sciences, School of Arts and Sciences, Rutgers University, New Brunswick, New Jersey, USA
| | - Juan Flores
- Department of Biological Sciences, Division of Life Sciences, School of Arts and Sciences, Rutgers University, Newark, New Jersey, USA
| | - Daniel Laubitz
- Department of Pediatrics, University of Arizona, Tucson, Arizona, USA
| | - Yanlin Zhao
- Center for Immunity and Inflammation, Rutgers New Jersey Medical School, Newark, New Jersey, USA
| | - George Yap
- Center for Immunity and Inflammation, Rutgers New Jersey Medical School, Newark, New Jersey, USA
| | - Jingren Wang
- Department of Mechanical and Aerospace Engineering, School of Engineering, Rutgers University, Piscataway, New Jersey, USA
| | - Qingze Zou
- Department of Mechanical and Aerospace Engineering, School of Engineering, Rutgers University, Piscataway, New Jersey, USA
| | - Ronaldo Ferraris
- Department of Pharmacology, Physiology and Neuroscience, Rutgers New Jersey Medical School, Newark, New Jersey, USA
| | - Lanjing Zhang
- Department of Biological Sciences, Division of Life Sciences, School of Arts and Sciences, Rutgers University, Newark, New Jersey, USA
- Department of Pathology, University Medical Center of Princeton, Plainsboro, New Jersey, USA
| | - Wenwei Hu
- Rutgers Cancer Institute of New Jersey, New Brunswick, New Jersey, USA
| | - Edward M. Bonder
- Department of Biological Sciences, Division of Life Sciences, School of Arts and Sciences, Rutgers University, Newark, New Jersey, USA
| | - Pawel R. Kiela
- Department of Pediatrics, University of Arizona, Tucson, Arizona, USA
| | - Robert Coffey
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, and Epithelial Biology Center, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Michael P. Verzi
- Department of Genetics, Division of Life Sciences, School of Arts and Sciences, Rutgers University, New Brunswick, New Jersey, USA
| | - Ivaylo I. Ivanov
- Department of Microbiology and Immunology, Vagelos College of Physicians and Surgeons, Columbia University, New York, New York, USA
| | - Nan Gao
- Department of Biological Sciences, Division of Life Sciences, School of Arts and Sciences, Rutgers University, Newark, New Jersey, USA
- Rutgers Cancer Institute of New Jersey, New Brunswick, New Jersey, USA
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11
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Pulido Companys P, Norris A, Bischoff M. Coordination of cytoskeletal dynamics and cell behaviour during Drosophila abdominal morphogenesis. J Cell Sci 2020; 133:jcs235325. [PMID: 32229579 PMCID: PMC7132776 DOI: 10.1242/jcs.235325] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Accepted: 01/20/2020] [Indexed: 12/20/2022] Open
Abstract
During morphogenesis, cells exhibit various behaviours, such as migration and constriction, which need to be coordinated. How this is achieved remains elusive. During morphogenesis of the Drosophila adult abdominal epidermis, larval epithelial cells (LECs) migrate directedly before constricting apically and undergoing apoptosis. Here, we study the mechanisms underlying the transition from migration to constriction. We show that LECs possess a pulsatile apical actomyosin network, and that a change in network polarity correlates with behavioural change. Exploring the properties of the contractile network, we find that cell contractility, as determined by myosin activity, has an impact on the behaviour of the network, as well as on cytoskeletal architecture and cell behaviour. Pulsed contractions occur only in cells with intermediate levels of contractility. Furthermore, increasing levels of the small Rho GTPase Rho1 disrupts pulsing, leading to cells that cycle between two states, characterised by a junctional cortical and an apicomedial actin network. Our results highlight that behavioural change relies on tightly controlled cellular contractility. Moreover, we show that constriction can occur without pulsing, raising questions why constricting cells pulse in some contexts but not in others.
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Affiliation(s)
- Pau Pulido Companys
- Biomedical Sciences Research Complex, University of St Andrews, North Haugh, St Andrews KY16 9ST, UK
| | - Anneliese Norris
- Biomedical Sciences Research Complex, University of St Andrews, North Haugh, St Andrews KY16 9ST, UK
| | - Marcus Bischoff
- Biomedical Sciences Research Complex, University of St Andrews, North Haugh, St Andrews KY16 9ST, UK
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12
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Hercyk BS, Rich-Robinson J, Mitoubsi AS, Harrell MA, Das ME. A novel interplay between GEFs orchestrates Cdc42 activity during cell polarity and cytokinesis in fission yeast. J Cell Sci 2019; 132:jcs.236018. [PMID: 31719163 DOI: 10.1242/jcs.229252/video-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Accepted: 11/04/2019] [Indexed: 05/23/2023] Open
Abstract
Cdc42, a conserved regulator of cell polarity, is activated by two GEFs, Gef1 and Scd1, in fission yeast. Why the cell needs two GEFs is unclear, given that they are partially redundant and activate the same GTPase. Using the GEF localization pattern during cytokinesis as a paradigm, we report a novel interplay between Gef1 and Scd1 that spatially modulates Cdc42. We find that Gef1 promotes Scd1 localization to the division site during cytokinesis through recruitment of the scaffold protein Scd2, via a Cdc42 feedforward pathway. Similarly, during interphase Gef1 promotes Scd1 recruitment at the new end to enable the transition from monopolar to bipolar growth. Reciprocally, Scd1 restricts Gef1 localization to prevent ectopic Cdc42 activation during cytokinesis to promote cell separation, and to maintain cell shape during interphase. Our findings reveal an elegant regulatory pattern in which Gef1 primes Cdc42 activation at new sites to initiate Scd1-dependent polarized growth, while Scd1 restricts Gef1 to sites of polarization. We propose that crosstalk between GEFs is a conserved mechanism that orchestrates Cdc42 activation during complex cellular processes.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Brian S Hercyk
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 7996-1939, USA
| | - Julie Rich-Robinson
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 7996-1939, USA
| | - Ahmad S Mitoubsi
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 7996-1939, USA
| | - Marcus A Harrell
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 7996-1939, USA
| | - Maitreyi E Das
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 7996-1939, USA
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13
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Hercyk BS, Rich-Robinson J, Mitoubsi AS, Harrell MA, Das ME. A novel interplay between GEFs orchestrates Cdc42 activity during cell polarity and cytokinesis in fission yeast. J Cell Sci 2019; 132:jcs.236018. [PMID: 31719163 DOI: 10.1242/jcs.236018] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Accepted: 11/04/2019] [Indexed: 12/12/2022] Open
Abstract
Cdc42, a conserved regulator of cell polarity, is activated by two GEFs, Gef1 and Scd1, in fission yeast. Why the cell needs two GEFs is unclear, given that they are partially redundant and activate the same GTPase. Using the GEF localization pattern during cytokinesis as a paradigm, we report a novel interplay between Gef1 and Scd1 that spatially modulates Cdc42. We find that Gef1 promotes Scd1 localization to the division site during cytokinesis through recruitment of the scaffold protein Scd2, via a Cdc42 feedforward pathway. Similarly, during interphase Gef1 promotes Scd1 recruitment at the new end to enable the transition from monopolar to bipolar growth. Reciprocally, Scd1 restricts Gef1 localization to prevent ectopic Cdc42 activation during cytokinesis to promote cell separation, and to maintain cell shape during interphase. Our findings reveal an elegant regulatory pattern in which Gef1 primes Cdc42 activation at new sites to initiate Scd1-dependent polarized growth, while Scd1 restricts Gef1 to sites of polarization. We propose that crosstalk between GEFs is a conserved mechanism that orchestrates Cdc42 activation during complex cellular processes.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Brian S Hercyk
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 7996-1939, USA
| | - Julie Rich-Robinson
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 7996-1939, USA
| | - Ahmad S Mitoubsi
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 7996-1939, USA
| | - Marcus A Harrell
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 7996-1939, USA
| | - Maitreyi E Das
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 7996-1939, USA
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14
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Letizia A, He D, Astigarraga S, Colombelli J, Hatini V, Llimargas M, Treisman JE. Sidekick Is a Key Component of Tricellular Adherens Junctions that Acts to Resolve Cell Rearrangements. Dev Cell 2019; 50:313-326.e5. [PMID: 31353315 DOI: 10.1016/j.devcel.2019.07.007] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 05/03/2019] [Accepted: 07/02/2019] [Indexed: 11/27/2022]
Abstract
Tricellular adherens junctions are points of high tension that are central to the rearrangement of epithelial cells. However, the molecular composition of these junctions is unknown, making it difficult to assess their role in morphogenesis. Here, we show that Sidekick, an immunoglobulin family cell adhesion protein, is highly enriched at tricellular adherens junctions in Drosophila. This localization is modulated by tension, and Sidekick is itself necessary to maintain normal levels of cell bond tension. Loss of Sidekick causes defects in cell and junctional rearrangements in actively remodeling epithelial tissues like the retina and tracheal system. The adaptor proteins Polychaetoid and Canoe are enriched at tricellular adherens junctions in a Sidekick-dependent manner; Sidekick functionally interacts with both proteins and directly binds to Polychaetoid. We suggest that Polychaetoid and Canoe link Sidekick to the actin cytoskeleton to enable tricellular adherens junctions to maintain or transmit cell bond tension during epithelial cell rearrangements.
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Affiliation(s)
- Annalisa Letizia
- Institut de Biologia Molecular de Barcelona, CSIC, Parc Científic de Barcelona, Baldiri Reixac, 10-12, Barcelona 08028, Spain
| | - DanQing He
- Kimmel Center for Biology and Medicine at the Skirball Institute and Department of Cell Biology, NYU School of Medicine, 540 First Avenue, New York, NY 10016, USA
| | - Sergio Astigarraga
- Kimmel Center for Biology and Medicine at the Skirball Institute and Department of Cell Biology, NYU School of Medicine, 540 First Avenue, New York, NY 10016, USA
| | - Julien Colombelli
- Institute for Research in Biomedicine, The Barcelona Institute of Science and Technology, Parc Científic de Barcelona, Baldiri Reixac, 10, Barcelona 08028, Spain
| | - Victor Hatini
- Department of Developmental, Molecular & Chemical Biology, Program in Cell, Molecular and Developmental Biology and Program in Genetics, Tufts University School of Medicine, 150 Harrison Avenue, Jaharis 322, Boston, MA 02111, USA
| | - Marta Llimargas
- Institut de Biologia Molecular de Barcelona, CSIC, Parc Científic de Barcelona, Baldiri Reixac, 10-12, Barcelona 08028, Spain.
| | - Jessica E Treisman
- Kimmel Center for Biology and Medicine at the Skirball Institute and Department of Cell Biology, NYU School of Medicine, 540 First Avenue, New York, NY 10016, USA.
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15
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The WAVE Regulatory Complex and Branched F-Actin Counterbalance Contractile Force to Control Cell Shape and Packing in the Drosophila Eye. Dev Cell 2018; 44:471-483.e4. [PMID: 29396116 DOI: 10.1016/j.devcel.2017.12.025] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 09/14/2017] [Accepted: 12/26/2017] [Indexed: 12/27/2022]
Abstract
Contractile forces eliminate cell contacts in many morphogenetic processes. However, mechanisms that balance contractile forces to promote subtler remodeling remain unknown. To address this gap, we investigated remodeling of Drosophila eye lattice cells (LCs), which preserve cell contacts as they narrow to form the edges of a multicellular hexagonal lattice. We found that during narrowing, LC-LC contacts dynamically constrict and expand. Similar to other systems, actomyosin-based contractile forces promote pulses of constriction. Conversely, we found that WAVE-dependent branched F-actin accumulates at LC-LC contacts during expansion and functions to expand the cell apical area, promote shape changes, and prevent elimination of LC-LC contacts. Finally, we found that small Rho GTPases regulate the balance of contractile and protrusive dynamics. These data suggest a mechanism by which WAVE regulatory complex-based F-actin dynamics antagonize contractile forces to regulate cell shape and tissue topology during remodeling and thus contribute to the robustness and precision of the process.
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16
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Brüser L, Bogdan S. Adherens Junctions on the Move-Membrane Trafficking of E-Cadherin. Cold Spring Harb Perspect Biol 2017; 9:cshperspect.a029140. [PMID: 28096264 DOI: 10.1101/cshperspect.a029140] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Cadherin-based adherens junctions are conserved structures that mediate epithelial cell-cell adhesion in invertebrates and vertebrates. Despite their pivotal function in epithelial integrity, adherens junctions show a remarkable plasticity that is a prerequisite for tissue architecture and morphogenesis. Epithelial cadherin (E-cadherin) is continuously turned over and undergoes cycles of endocytosis, sorting and recycling back to the plasma membrane. Mammalian cell culture and genetically tractable model systems such as Drosophila have revealed conserved, but also distinct, mechanisms in the regulation of E-cadherin membrane trafficking. Here, we discuss our current knowledge about molecules and mechanisms controlling endocytosis, sorting and recycling of E-cadherin during junctional remodeling.
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Affiliation(s)
- Lena Brüser
- Institut für Neurobiologie, Universität Münster, Badestraße 9, 48149 Münster, Germany
| | - Sven Bogdan
- Institut für Neurobiologie, Universität Münster, Badestraße 9, 48149 Münster, Germany.,Institut für Physiologie und Pathophysiologie, Abteilung Molekulare Zellphysiologie, Phillips-Universität Marburg, Emil-Mannkopff-Straße 2, 35037 Marburg, Germany
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17
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Schimizzi GV, Maher MT, Loza AJ, Longmore GD. Disruption of the Cdc42/Par6/aPKC or Dlg/Scrib/Lgl Polarity Complex Promotes Epithelial Proliferation via Overlapping Mechanisms. PLoS One 2016; 11:e0159881. [PMID: 27454609 PMCID: PMC4959776 DOI: 10.1371/journal.pone.0159881] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Accepted: 07/08/2016] [Indexed: 11/18/2022] Open
Abstract
The establishment and maintenance of apical-basal polarity is a defining characteristic and essential feature of functioning epithelia. Apical-basal polarity (ABP) proteins are also tumor suppressors that are targeted for disruption by oncogenic viruses and are commonly mutated in human carcinomas. Disruption of these ABP proteins is an early event in cancer development that results in increased proliferation and epithelial disorganization through means not fully characterized. Using the proliferating Drosophila melanogaster wing disc epithelium, we demonstrate that disruption of the junctional vs. basal polarity complexes results in increased epithelial proliferation via distinct downstream signaling pathways. Disruption of the basal polarity complex results in JNK-dependent proliferation, while disruption of the junctional complex primarily results in p38-dependent proliferation. Surprisingly, the Rho-Rok-Myosin contractility apparatus appears to play opposite roles in the regulation of the proliferative phenotype based on which polarity complex is disrupted. In contrast, non-autonomous Tumor Necrosis Factor (TNF) signaling appears to suppress the proliferation that results from apical-basal polarity disruption, regardless of which complex is disrupted. Finally we demonstrate that disruption of the junctional polarity complex activates JNK via the Rho-Rok-Myosin contractility apparatus independent of the cortical actin regulator, Moesin.
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Affiliation(s)
- Gregory V. Schimizzi
- ICCE Institute, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Meghan T. Maher
- ICCE Institute, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Andrew J. Loza
- ICCE Institute, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Computational and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Gregory D. Longmore
- ICCE Institute, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, United States of America
- * E-mail:
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18
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Fujiwara M, Okamoto M, Hori M, Suga H, Jikihara H, Sugihara Y, Shimamoto F, Mori T, Nakaoji K, Hamada K, Ota T, Wiedemuth R, Temme A, Tatsuka M. Radiation-Induced RhoGDIβ Cleavage Leads to Perturbation of Cell Polarity: A Possible Link to Cancer Spreading. J Cell Physiol 2016; 231:2493-505. [DOI: 10.1002/jcp.25362] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2015] [Accepted: 02/23/2016] [Indexed: 01/17/2023]
Affiliation(s)
- Mamoru Fujiwara
- Faculty of Life and Environmental Sciences; Department of Life Sciences; Prefectural University of Hiroshima; Shoubara Hiroshima Japan
| | - Mayumi Okamoto
- Faculty of Life and Environmental Sciences; Department of Life Sciences; Prefectural University of Hiroshima; Shoubara Hiroshima Japan
| | - Masato Hori
- Faculty of Life and Environmental Sciences; Department of Life Sciences; Prefectural University of Hiroshima; Shoubara Hiroshima Japan
| | - Hiroshi Suga
- Faculty of Life and Environmental Sciences; Department of Life Sciences; Prefectural University of Hiroshima; Shoubara Hiroshima Japan
| | - Hiroshi Jikihara
- Department of Health Sciences; Faculty of Human Culture and Science; Prefectural University of Hiroshima; Minami-ku Hiroshima Japan
| | - Yuka Sugihara
- Department of Health Sciences; Faculty of Human Culture and Science; Prefectural University of Hiroshima; Minami-ku Hiroshima Japan
| | - Fumio Shimamoto
- Department of Health Sciences; Faculty of Human Culture and Science; Prefectural University of Hiroshima; Minami-ku Hiroshima Japan
| | - Toshio Mori
- Radioisotope Research Center; Nara Medical University School of Medicine; Kashihara Nara Japan
| | - Koichi Nakaoji
- Research & Development Division; Pias Corporation; Kobe Japan
| | - Kazuhiko Hamada
- Research & Development Division; Pias Corporation; Kobe Japan
| | - Takahide Ota
- Department of Life Science; Medical Research Institute; Kanazawa Medical University; Uchinada Ishikawa Japan
| | - Ralf Wiedemuth
- Department of Neurosurgery; University Hospital Carl Gustav Carus; Technical University Dresden; Dresden Germany
| | - Achim Temme
- Department of Neurosurgery; University Hospital Carl Gustav Carus; Technical University Dresden; Dresden Germany
| | - Masaaki Tatsuka
- Faculty of Life and Environmental Sciences; Department of Life Sciences; Prefectural University of Hiroshima; Shoubara Hiroshima Japan
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19
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Muccioli M, Qaisi D, Herman K, Plageman TF. Lens placode planar cell polarity is dependent on Cdc42-mediated junctional contraction inhibition. Dev Biol 2016; 412:32-43. [PMID: 26902112 DOI: 10.1016/j.ydbio.2016.02.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 02/17/2016] [Accepted: 02/18/2016] [Indexed: 12/18/2022]
Abstract
Development of the ocular lens commences with the formation of the lens placode, an epithelial structure that thickens and subsequently bends inward in a process called invagination. Invagination is observed during the development of many embryonic structures, but the spectrum of morphogenetic events driving this process are, in most cases, not fully understood. A characteristic commonly found in embryonic tissues undergoing epithelial reorganization is planar polarity, a property where cells are geometrically and/or molecularly orientated in a specific direction along the plane of an epithelium. Planar polarity is known to drive the morphogenesis of several epithelial structures, however its role during invagination events is less clear. We have found that at the onset of invagination, cells of the lens placode become geometrically planar polarized such that they are orientated toward a central point in the lens placode. Further investigation revealed that this is due to contraction of radially orientated junctions and the elongation of those circumferentially orientated. Radial junctions have an elevated localization of actomyosin and their contraction is dependent on the F-actin and Rho-kinase binding protein, Shroom3. Elongation of circumferential junctions is dependent upon Cdc42, a Rho-GTPase known to regulate polarity via the Par-complex. We determined that Cdc42 and members of the Par-complex inhibit Shroom3-induced contractility and promote anisotropic placode cell geometry through inhibition of junctional contraction. We postulate that invagination of the lens placode requires careful orchestration of these opposing processes which are mediated by the planar polarization of junctional proteins.
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Affiliation(s)
- Maria Muccioli
- College of Optometry, The Ohio State University, Columbus, OH 43210, United States
| | - Dalya Qaisi
- College of Optometry, The Ohio State University, Columbus, OH 43210, United States
| | - Ken Herman
- College of Optometry, The Ohio State University, Columbus, OH 43210, United States
| | - Timothy F Plageman
- College of Optometry, The Ohio State University, Columbus, OH 43210, United States
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20
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Loebel DAF, Plageman TF, Tang TL, Jones VJ, Muccioli M, Tam PPL. Thyroid bud morphogenesis requires CDC42- and SHROOM3-dependent apical constriction. Biol Open 2016; 5:130-9. [PMID: 26772200 PMCID: PMC4823982 DOI: 10.1242/bio.014415] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Early development of the gut endoderm and its subsequent remodeling for the formation of organ buds are accompanied by changes to epithelial cell shape and polarity. Members of the Rho-related family of small GTPases and their interacting proteins play multiple roles in regulating epithelial morphogenesis. In this study we examined the role of Cdc42 in foregut development and organ bud formation. Ablation of Cdc42 in post-gastrulation mouse embryos resulted in a loss of apical-basal cell polarity and columnar epithelial morphology in the ventral pharyngeal endoderm, in conjunction with a loss of apical localization of the known CDC42 effector protein PARD6B. Cell viability but not proliferation in the foregut endoderm was impaired. Outgrowth of the liver, lung and thyroid buds was severely curtailed in Cdc42-deficient embryos. In particular, the thyroid bud epithelium did not display the apical constriction that normally occurs concurrently with the outgrowth of the bud into the underlying mesenchyme. SHROOM3, a protein that interacts with Rho GTPases and promotes apical constriction, was strongly expressed in the thyroid bud and its sub-cellular localization was disrupted in Cdc42-deficient embryos. In Shroom3 gene trap mutant embryos, the thyroid bud epithelium showed no apical constriction, while the bud continued to grow and protruded into the foregut lumen. Our findings indicate that Cdc42 is required for epithelial polarity and organization in the endoderm and for apical constriction in the thyroid bud. It is possible that the function of CDC42 is partly mediated by SHROOM3. Summary: Conditional Cdc42 knockout revealed requirements for Cdc42 in endoderm polarity, and in thyroid apical constriction and morphogenesis. Shroom3 mutant embryos also displayed thyroid bud abnormalities, suggesting a possible functional interaction.
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Affiliation(s)
- David A F Loebel
- Embryology Unit, Children's Medical Research Institute, Locked Bag 32, Wentworthville, New South Wales 2145, Australia Sydney Medical School, University of Sydney, Sydney, New South Wales 2006, Australia
| | - Timothy F Plageman
- Ohio State University College of Optometry, Columbus, OH 43210-1280, USA
| | - Theresa L Tang
- Embryology Unit, Children's Medical Research Institute, Locked Bag 32, Wentworthville, New South Wales 2145, Australia
| | - Vanessa J Jones
- Embryology Unit, Children's Medical Research Institute, Locked Bag 32, Wentworthville, New South Wales 2145, Australia
| | - Maria Muccioli
- Ohio State University College of Optometry, Columbus, OH 43210-1280, USA
| | - Patrick P L Tam
- Embryology Unit, Children's Medical Research Institute, Locked Bag 32, Wentworthville, New South Wales 2145, Australia Sydney Medical School, University of Sydney, Sydney, New South Wales 2006, Australia
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21
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Abstract
The establishment and maintenance of epithelial cell-cell junctions is crucially important to regulate adhesion, apico-basal polarity and motility of epithelial cells, and ultimately controls the architecture and physiology of epithelial organs. Junctions are supported, shaped and regulated by cytoskeletal filaments, whose dynamic organization and contractility are finely tuned by GTPases of the Rho family, primarily RhoA, Rac1 and Cdc42. Recent research has identified new molecular mechanisms underlying the cross-talk between these GTPases and epithelial junctions. Here we briefly summarize the current knowledge about the organization, molecular evolution and cytoskeletal anchoring of cell-cell junctions, and we comment on the most recent advances in the characterization of the interactions between Rho GTPases and junctional proteins, and their consequences with regards to junction assembly and regulation of cell behavior in vertebrate model systems. The concept of “zonular signalosome” is proposed, which highlights the close functional relationship between proteins of zonular junctions (zonulae occludentes and adhaerentes) and the control of cytoskeletal organization and signaling through Rho GTPases, transcription factors, and their effectors.
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Key Words
- AJ, adherens junction
- AMOT, angiomotin
- AMPK, Adenosine Monophosphate-Activated Protein Kinase
- APC, adenomatous poliposis coli
- CD2AP, CD2-associated protein
- CGN, cingulin
- CGNL1, paracingulin
- Cdc42
- Cdc42, cell division cycle 42
- DLC, deleted in liver cancer
- Dbl, diffuse B-cell lymphoma
- EPLIN, epithelial protein lost in neoplasm
- ERK, extracellular regulated kinase
- FERM, four.point.one, ezrin, radixin, moesin
- FGD5, FYVE, RhoGEF and PH domain containing 5
- GAP, GTPase activating protein
- GEF, guanine nucleotide exchange factor
- GST, glutathione -S- transferase; JAM = junctional adhesion molecule
- MCF-7, Michigan Cancer Foundation - 7
- MDCK, Madin Darby Canine Kidney
- MKLP1, mitotic kinesin-like protein-1
- MRCK, myotonic dystrophy-related Cdc42-binding kinase
- MgcRacGAP, male germ cell racGAP
- PA, puncta adhaerentia
- PAK, p21-activated kinase; PATJ, Pals1 associated tight junction protein
- PCNA, proliferating cell nuclear antigen
- PDZ, Post synaptic density protein (PSD95), Drosophila, disc large tumour suppressor (DlgA), and zonula occludens-1
- PLEKHA7, pleckstrin homology domain containing, family A member 7
- RICH-1, RhoGAP interacting with CIP4 homologues
- ROCK, Rho-associated protein kinase
- Rac
- Rho
- SH3BP1, (SH3 domain 490 binding protein-1)
- TJ, tight junction
- Tbx-3, T-box-3
- Tiam, Tumor invasion and metastasis
- WASP, Wiskott-Aldrich Syndrome Protein
- WAVE, WASP family Verprolin-homologous protein
- ZA, zonula adhaerens
- ZO, zonula occludens
- ZONAB, (ZO-1)–associated nucleic acid binding protein.
- cytoseleton
- epithelium
- junctions
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Affiliation(s)
- Sandra Citi
- a Department of Cell Biology ; University of Geneva ; Geneva , Switzerland
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22
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Abstract
Signaling via the Rho GTPases provides crucial regulation of numerous cell polarization events, including apicobasal (AB) polarity, polarized cell migration, polarized cell division and neuronal polarity. Here we review the relationships between the Rho family GTPases and epithelial AB polarization events, focusing on the 3 best-characterized members: Rho, Rac and Cdc42. We discuss a multitude of processes that are important for AB polarization, including lumen formation, apical membrane specification, cell-cell junction assembly and maintenance, as well as tissue polarity. Our discussions aim to highlight the immensely complex regulatory mechanisms that encompass Rho GTPase signaling during AB polarization. More specifically, in this review we discuss several emerging common themes, that include: 1) the need for Rho GTPase activities to be carefully balanced in both a spatial and temporal manner through a multitude of mechanisms; 2) the existence of signaling feedback loops and crosstalk to create robust cellular responses; and 3) the frequent multifunctionality that exists among AB polarity regulators. Regarding this latter theme, we provide further discussion of the potential plasticity of the cell polarity machinery and as a result the possible implications for human disease.
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Key Words
- AB, Apicobasal
- AJ, Adherens junction
- Amot, Angiomotin
- Arp2/3, Actin-related protein-2/3
- Baz, Bazooka
- C. elegans, Caenorhabditis elegans
- CA, Constitutively-active
- CD2AP, CD2-associated protein
- Caco2, Human colon carcinoma
- Cdc42
- Cora, Coracle
- Crb, Crumbs
- DN, Dominant-negative
- Dia1, Diaphanous-related formin 1
- Dlg, Discs large
- Drosophila, Drosophila melanogaster
- Dys-β, Dystrobrevin-β
- ECM, Extracellular matrix
- Ect2, Epithelial cell transforming sequence 2 oncogene
- Eya1, Eyes absent 1
- F-actin, Filamentous actin
- FRET, Fluorescence resonance energy transfer
- GAP, GTPase-activating protein
- GDI, Guanine nucleotide dissociation inhibitor
- GEF, Guanine nucleotide exchange factor
- GTPases
- JACOP, Junction-associated coiled-coiled protein
- JAM, Junctional adhesion molecule
- LKB1, Liver kinase B1
- Lgl, Lethal giant larvae
- MDCK, Madin-Darby canine kidney
- MTOC, Microtubule-organizing center
- NrxIV, Neurexin IV
- Pals1, Protein associated with Lin-7 1
- Par, Partitioning-defective
- Patj, Pals1-associated TJ protein
- ROCK, Rho-associated kinase
- Rac
- Rho
- Rich1, RhoGAP interacting with CIP4 homologues
- S. cerevisiae, Saccharomyces cerevisiae
- S. pombe, Schizosaccharomyces pombe
- SH3BP1, SH3-domain binding protein 1
- Scrib, Scribble
- Std, Stardust
- TEM4, Tumor endothelial marker 4
- TJ, Tight junction
- Tiam1, T-cell lymphoma invasion and metastasis-inducing protein 1
- WASp, Wiskott-aldrich syndrome protein
- Yrt, Yurt
- ZA, zonula adherens
- ZO, Zonula occludens
- aPKC, Atypical Protein Kinase C
- apicobasal
- epithelia
- junction
- par
- polarity
- α-cat, Alpha-catenin
- β-cat, Beta-Catenin
- β2-syn, Beta-2-syntrophin
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Affiliation(s)
- Natalie Ann Mack
- a School of Life Sciences; Queens Medical Center ; University of Nottingham ; Nottingham , UK
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Meserve JH, Duronio RJ. Scalloped and Yorkie are required for cell cycle re-entry of quiescent cells after tissue damage. Development 2015; 142:2740-51. [PMID: 26160905 DOI: 10.1242/dev.119339] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Accepted: 06/29/2015] [Indexed: 12/19/2022]
Abstract
Regeneration of damaged tissues typically requires a population of active stem cells. How damaged tissue is regenerated in quiescent tissues lacking a stem cell population is less well understood. We used a genetic screen in the developing Drosophila melanogaster eye to investigate the mechanisms that trigger quiescent cells to re-enter the cell cycle and proliferate in response to tissue damage. We discovered that Hippo signaling regulates compensatory proliferation after extensive cell death in the developing eye. Scalloped and Yorkie, transcriptional effectors of the Hippo pathway, drive Cyclin E expression to induce cell cycle re-entry in cells that normally remain quiescent in the absence of damage. Ajuba, an upstream regulator of Hippo signaling that functions as a sensor of epithelial integrity, is also required for cell cycle re-entry. Thus, in addition to its well-established role in modulating proliferation during periods of tissue growth, Hippo signaling maintains homeostasis by regulating quiescent cell populations affected by tissue damage.
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Affiliation(s)
- Joy H Meserve
- Curriculum in Genetics & Molecular Biology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Robert J Duronio
- Curriculum in Genetics & Molecular Biology, University of North Carolina, Chapel Hill, NC 27599, USA Integrative Program for Biological and Genome Sciences, University of North Carolina, Chapel Hill, NC 27599, USA Departments of Biology and Genetics, University of North Carolina, Chapel Hill, NC 27599, USA Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599, USA
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24
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de Beco S, Perney JB, Coscoy S, Amblard F. Mechanosensitive Adaptation of E-Cadherin Turnover across adherens Junctions. PLoS One 2015; 10:e0128281. [PMID: 26046627 PMCID: PMC4457789 DOI: 10.1371/journal.pone.0128281] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Accepted: 04/23/2015] [Indexed: 11/18/2022] Open
Abstract
In the natural and technological world, multi-agent systems strongly depend on how the interactions are ruled between their individual components, and the proper control of time-scales and synchronization is a key issue. This certainly applies to living tissues when multicellular assemblies such as epithelial cells achieve complex morphogenetic processes. In epithelia, because cells are known to individually generate actomyosin contractile stress, each individual intercellular adhesive junction line is subjected to the opposed stresses independently generated by its two partner cells. Contact lines should thus move unless their two partner cells mechanically match. The geometric homeostasis of mature epithelia observed at short enough time-scale thus raises the problem to understand how cells, if considered as noisy individual actuators, do adapt across individual intercellular contacts to locally balance their time-average contractile stress. Structural components of adherens junctions, cytoskeleton (F-actin) and homophilic bonds (E-cadherin) are quickly renewed at steady-state. These turnovers, if they depend on forces exerted at contacts, may play a key role in the mechanical adaptation of epithelia. Here we focus on E-cadherin as a force transducer, and we study the local regulation and the mechanosensitivity of its turnover in junctions. We show that E-cadherin turnover rates match remarkably well on either side of mature intercellular contacts, despite the fact that they exhibit large fluctuations in time and variations from one junction to another. Using local mechanical and biochemical perturbations, we find faster turnover rates with increased tension, and asymmetric rates at unbalanced junctions. Together, the observations that E-cadherin turnover, and its local symmetry or asymmetry at each side of the junction, are mechanosensitive, support the hypothesis that E-cadherin turnover could be involved in mechanical homeostasis of epithelia.
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Affiliation(s)
- Simon de Beco
- Laboratoire de Physico-Chimie, Centre de Recherche, Institut Curie, Paris, France
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 168, Paris, France
- Université Pierre et Marie Curie, Paris, France
| | - Jean-Baptiste Perney
- Laboratoire de Physico-Chimie, Centre de Recherche, Institut Curie, Paris, France
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 168, Paris, France
- Université Pierre et Marie Curie, Paris, France
| | - Sylvie Coscoy
- Laboratoire de Physico-Chimie, Centre de Recherche, Institut Curie, Paris, France
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 168, Paris, France
- Université Pierre et Marie Curie, Paris, France
| | - François Amblard
- Laboratoire de Physico-Chimie, Centre de Recherche, Institut Curie, Paris, France
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 168, Paris, France
- Université Pierre et Marie Curie, Paris, France
- * E-mail:
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25
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Martín-Bermudo MD, Bardet PL, Bellaïche Y, Malartre M. The vav oncogene antagonises EGFR signalling and regulates adherens junction dynamics during Drosophila eye development. Development 2015; 142:1492-501. [PMID: 25813543 DOI: 10.1242/dev.110585] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Accepted: 03/02/2015] [Indexed: 12/13/2022]
Abstract
Organ shaping and patterning depends on the coordinated regulation of multiple processes. The Drosophila compound eye provides an excellent model to study the coordination of cell fate and cell positioning during morphogenesis. Here, we find that loss of vav oncogene function during eye development is associated with a disorganised retina characterised by the presence of additional cells of all types. We demonstrate that these defects result from two distinct roles of Vav. First, and in contrast to its well-established role as a positive effector of the EGF receptor (EGFR), we show that readouts of the EGFR pathway are upregulated in vav mutant larval eye disc and pupal retina, indicating that Vav antagonises EGFR signalling during eye development. Accordingly, decreasing EGFR signalling in vav mutant eyes restores retinal organisation and rescues most vav mutant phenotypes. Second, using live imaging in the pupal retina, we observe that vav mutant cells do not form stable adherens junctions, causing various defects, such as recruitment of extra primary pigment cells. In agreement with this role in junction dynamics, we observe that these phenotypes can be exacerbated by lowering DE-Cadherin or Cindr levels. Taken together, our findings establish that Vav acts at multiple times during eye development to prevent excessive cell recruitment by limiting EGFR signalling and by regulating junction dynamics to ensure the correct patterning and morphogenesis of the Drosophila eye.
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Affiliation(s)
| | - Pierre-Luc Bardet
- Institut Curie, CNRS UMR3215, INSERM U934, Paris Cedex 05 75248, France
| | - Yohanns Bellaïche
- Institut Curie, CNRS UMR3215, INSERM U934, Paris Cedex 05 75248, France
| | - Marianne Malartre
- Centro Andaluz de Biología del Desarrollo CSIC-Univ. Pablo de Olavide, Sevilla 41013, Spain Université Paris-Sud, INSERM UMR-S757, Orsay 91405, France Centre de Génétique Moléculaire (UPR3404), CNRS, 1 avenue de la Terrasse, Gif-Sur-Yvette 91198, France
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26
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Rosa A, Vlassaks E, Pichaud F, Baum B. Ect2/Pbl acts via Rho and polarity proteins to direct the assembly of an isotropic actomyosin cortex upon mitotic entry. Dev Cell 2015; 32:604-16. [PMID: 25703349 PMCID: PMC4359025 DOI: 10.1016/j.devcel.2015.01.012] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2014] [Revised: 10/06/2014] [Accepted: 01/14/2015] [Indexed: 02/06/2023]
Abstract
Entry into mitosis is accompanied by profound changes in cortical actomyosin organization. Here, we delineate a pathway downstream of the RhoGEF Pbl/Ect2 that directs this process in a model epithelium. Our data suggest that the release of Pbl/Ect2 from the nucleus at mitotic entry drives Rho-dependent activation of Myosin-II and, in parallel, induces a switch from Arp2/3 to Diaphanous-mediated cortical actin nucleation that depends on Cdc42, aPKC, and Par6. At the same time, the mitotic relocalization of these apical protein complexes to more lateral cell surfaces enables Cdc42/aPKC/Par6 to take on a mitosis-specific function—aiding the assembly of a relatively isotropic metaphase cortex. Together, these data reveal how the repolarization and remodeling of the actomyosin cortex are coordinated upon entry into mitosis to provide cells with the isotropic and rigid form they need to undergo faithful chromosome segregation and division in a crowded tissue environment. Pbl/Ect2 drives a shift in epithelial polarity upon entry into mitosis Lateral spreading of Cdc42/aPKC/Par6 aids assembly of an isotropic metaphase cortex Mitosis triggers a switch from Arp2/3 to Dia-mediated cortical actin nucleation
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Affiliation(s)
- André Rosa
- MRC Laboratory of Molecular Cell Biology, UCL, Gower Street, London WC1E 6BT, UK; Graduate Program in Areas of Basic and Applied Biology (GABBA), University of Porto, 4200-465 Porto, Portugal
| | - Evi Vlassaks
- MRC Laboratory of Molecular Cell Biology, UCL, Gower Street, London WC1E 6BT, UK
| | - Franck Pichaud
- MRC Laboratory of Molecular Cell Biology, UCL, Gower Street, London WC1E 6BT, UK
| | - Buzz Baum
- MRC Laboratory of Molecular Cell Biology, UCL, Gower Street, London WC1E 6BT, UK.
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27
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Yashiro H, Loza AJ, Skeath JB, Longmore GD. Rho1 regulates adherens junction remodeling by promoting recycling endosome formation through activation of myosin II. Mol Biol Cell 2014; 25:2956-69. [PMID: 25079692 PMCID: PMC4230585 DOI: 10.1091/mbc.e14-04-0894] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Once adherens junctions (AJs) are formed between polarized epithelial cells they must be maintained because AJs are constantly remodeled in dynamic epithelia. AJ maintenance involves endocytosis and subsequent recycling of E-cadherin to a precise location along the basolateral membrane. In the Drosophila pupal eye epithelium, Rho1 GTPase regulates AJ remodeling through Drosophila E-cadherin (DE-cadherin) endocytosis by limiting Cdc42/Par6/aPKC complex activity. We demonstrate that Rho1 also influences AJ remodeling by regulating the formation of DE-cadherin-containing, Rab11-positive recycling endosomes in Drosophila postmitotic pupal eye epithelia. This effect of Rho1 is mediated through Rok-dependent, but not MLCK-dependent, stimulation of myosin II activity yet independent of its effects upon actin remodeling. Both Rho1 and pMLC localize on endosomal vesicles, suggesting that Rho1 might regulate the formation of recycling endosomes through localized myosin II activation. This work identifies spatially distinct functions for Rho1 in the regulation of DE-cadherin-containing vesicular trafficking during AJ remodeling in live epithelia.
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Affiliation(s)
- Hanako Yashiro
- ICCE Institute, Washington University School of Medicine, St. Louis, MO 63110 Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110 Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110
| | - Andrew J Loza
- ICCE Institute, Washington University School of Medicine, St. Louis, MO 63110 Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110
| | - James B Skeath
- Department of Genetics, Washington University School of Medicine, St. Louis, MO 63110
| | - Gregory D Longmore
- ICCE Institute, Washington University School of Medicine, St. Louis, MO 63110 Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110 Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110 BRIGHT Institute, Washington University School of Medicine, St. Louis, MO 63110
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28
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Abstract
Differential adhesion provides a mechanical force to drive cells into stable configurations during the assembly of tissues and organs. This is well illustrated in the Drosophila eye where differential adhesion plays a role in sequential recruitment of all support cells. Cell adhesion, on the other hand, is linked to the cytoskeleton and subject to regulation by cell signaling. The integration of cell adhesion with the cytoskeleton and cell signaling may provide a more thorough explanation for the diversity of forms and shapes seen in tissues and organs.
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Affiliation(s)
- Sujin Bao
- Saint James School of Medicine , Bonaire , Caribbean Netherlands
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29
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Clay MR, Halloran MC. Rho activation is apically restricted by Arhgap1 in neural crest cells and drives epithelial-to-mesenchymal transition. Development 2013; 140:3198-209. [PMID: 23804498 DOI: 10.1242/dev.095448] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Epithelial-to-mesenchymal transitions (EMTs) are crucial for morphogenesis and carcinoma metastasis, yet mechanisms controlling the underlying cell behaviors are poorly understood. RhoGTPase signaling has been implicated in EMT; however, previous studies have yielded conflicting results regarding Rho function, and its role in EMT remains poorly understood. Elucidation of precise Rho functions has been challenging because Rho signaling is highly context dependent and its activity is tightly regulated spatiotemporally within the cell. To date, few studies have examined how Rho affects cell motility in intact organisms, and the pattern of Rho activity during motile cell behaviors of EMT has not been determined in any system. Here, we image endogenous active Rho during EMT in vivo, and analyze effects of Rho and Rho-kinase (ROCK) manipulation on cell motility in vivo. We show that Rho is activated in a discrete apical region of premigratory neural crest cells during EMT, and Rho-ROCK signaling is essential for apical detachment and generation of motility within the neuroepithelium, a process that has been poorly understood. Furthermore, we find that Arhgap1 restricts Rho activation to apical areas, and this restriction is necessary for detachment. Our results provide new insight into mechanisms controlling local Rho activation and how it affects dynamic cell behaviors and actomyosin contraction during key steps of EMT in an intact living organism.
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Affiliation(s)
- Matthew R Clay
- Cell and Molecular Biology Program, University of Wisconsin, Madison, WI 53706, USA
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30
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Zhang L, Gallup M, Zlock L, Finkbeiner WE, McNamara NA. Rac1 and Cdc42 differentially modulate cigarette smoke-induced airway cell migration through p120-catenin-dependent and -independent pathways. THE AMERICAN JOURNAL OF PATHOLOGY 2013; 182:1986-95. [PMID: 23562274 PMCID: PMC5691327 DOI: 10.1016/j.ajpath.2013.02.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2012] [Revised: 02/04/2013] [Accepted: 02/20/2013] [Indexed: 01/10/2023]
Abstract
The adherens junction protein p120-catenin (p120ctn) shuttles between E-cadherin-bound and cytoplasmic pools to regulate E-cadherin/catenin complex stability and cell migration, respectively. When released from the adherens junction, p120ctn promotes cell migration through modulation of the Rho GTPases Rac1, Cdc42, and RhoA. Accordingly, the down-regulation and cytoplasmic mislocalization of p120ctn has been reported in all subtypes of lung cancers and is associated with grave prognosis. Previously, we reported that cigarette smoke induced cytoplasmic translocation of p120ctn and cell migration, but the underlying mechanism was unclear. Using primary human bronchial epithelial cells exposed to smoke-concentrated medium (Smk), we observed the translocation of Rac1 and Cdc42, but not RhoA, to the leading edge of polarized and migrating human bronchial epithelial cells. Rac1 and Cdc42 were robustly activated by smoke, whereas RhoA was inhibited. Accordingly, siRNA knockdown of Rac1 or Cdc42 completely abolished Smk-induced cell migration, whereas knockdown of RhoA had no effect. p120ctn/Rac1 double knockdown completely abolished Smk-induced cell migration, whereas p120ctn/Cdc42 double knockdown did not. These data suggested that Rac1 and Cdc42 coactivation was essential to smoke-promoted cell migration in the presence of p120ctn, whereas migration proceeded via Rac1 alone in the absence of p120ctn. Thus, Rac1 may provide an omnipotent therapeutic target in reversing cell migration during the early (intact p120ctn) and late (loss of p120ctn) stages of lung carcinogenesis.
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Affiliation(s)
- Lili Zhang
- Francis I. Proctor Foundation, University of California, San Francisco, California
| | - Marianne Gallup
- Francis I. Proctor Foundation, University of California, San Francisco, California
| | - Lorna Zlock
- Department of Pathology, University of California, San Francisco, California
| | | | - Nancy A. McNamara
- Francis I. Proctor Foundation, University of California, San Francisco, California
- Department of Anatomy and Ophthalmology, University of California, San Francisco, California
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31
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Cdc42 is involved in basal cell carcinoma carcinogenesis. Arch Dermatol Res 2013; 305:835-40. [PMID: 23589095 DOI: 10.1007/s00403-013-1351-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Accepted: 03/30/2013] [Indexed: 12/20/2022]
Abstract
Basal cell carcinoma (BCC) is the most common type of skin cancer in older persons and is a rapidly rising incidence. E-cadherin-mediated cell-cell adhesion activates Cdc42, a Rho GTPase essential for cell polarity in numerous settings. No study has yet addressed a biological significance of Cdc42 alterations in BCC pathogenesis. Our aim was to investigate E-cadherin-dependent cell-cell contacts and Cdc42 activity in BCC formation. We evaluated E-cadherin and Cdc42 expression by immunohistochemistry and Western blot analysis in samples of 15 normal skin (NS) and 30 BCC (10 superficial, 9 nodular and 11 infiltrative subtypes). Low E-cadherin and high Cdc42 immunohistochemical expression were found in BCC samples compared with NS. E-cadherin staining was significantly reduced in infiltrative BCC compared with superficial and nodular. A significantly greater Cdc42 expression was observed in BCC compared with NS; moreover, superficial BCC had a significantly lower Cdc42 expression in respect to the other subtypes. Western blot analysis confirmed the significantly decreased E-cadherin expression in infiltrative BCC as well as Cdc42 reduction in superficial BCC in respect to the other subtypes. In BCC the increased Cdc42 in association with reduced E-cadherin might contribute to the disruption of adhesion mechanisms and to the loss of cell polarity, thus explaining a mechanism by which cancer cells can escape from the control of adjacent normal keratinocytes. Our study also showed that Cdc42 and E-cadherin expression differed according to aggressive behaviour of BCC subtypes and suggested important functions of these molecules in regulating tumour demarcation and progression.
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32
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Herszterg S, Leibfried A, Bosveld F, Martin C, Bellaiche Y. Interplay between the Dividing Cell and Its Neighbors Regulates Adherens Junction Formation during Cytokinesis in Epithelial Tissue. Dev Cell 2013; 24:256-70. [DOI: 10.1016/j.devcel.2012.11.019] [Citation(s) in RCA: 125] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2012] [Revised: 11/15/2012] [Accepted: 11/17/2012] [Indexed: 12/31/2022]
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33
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Choi W, Harris NJ, Sumigray KD, Peifer M. Rap1 and Canoe/afadin are essential for establishment of apical-basal polarity in the Drosophila embryo. Mol Biol Cell 2013; 24:945-63. [PMID: 23363604 PMCID: PMC3608504 DOI: 10.1091/mbc.e12-10-0736] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The small GTPase Rap1 and the actin-junctional linker protein Canoe/afadin are essential for the initial establishment of polarity in Drosophila, acting upstream of Bazooka/Par3 and the adherens junctions. However, feedback and cross-regulation occur, so polarity establishment is regulated by a network of proteins rather than a linear pathway. The establishment and maintenance of apical–basal cell polarity is critical for assembling epithelia and maintaining organ architecture. Drosophila embryos provide a superb model. In the current view, apically positioned Bazooka/Par3 is the initial polarity cue as cells form during cellularization. Bazooka then helps to position both adherens junctions and atypical protein kinase C (aPKC). Although a polarized cytoskeleton is critical for Bazooka positioning, proteins mediating this remained unknown. We found that the small GTPase Rap1 and the actin-junctional linker Canoe/afadin are essential for polarity establishment, as both adherens junctions and Bazooka are mispositioned in their absence. Rap1 and Canoe do not simply organize the cytoskeleton, as actin and microtubules become properly polarized in their absence. Canoe can recruit Bazooka when ectopically expressed, but they do not obligatorily colocalize. Rap1 and Canoe play continuing roles in Bazooka localization during gastrulation, but other polarity cues partially restore apical Bazooka in the absence of Rap1 or Canoe. We next tested the current linear model for polarity establishment. Both Bazooka and aPKC regulate Canoe localization despite being “downstream” of Canoe. Further, Rap1, Bazooka, and aPKC, but not Canoe, regulate columnar cell shape. These data reshape our view, suggesting that polarity establishment is regulated by a protein network rather than a linear pathway.
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Affiliation(s)
- Wangsun Choi
- Department of Biology, University of North Carolina, Chapel Hill, NC, USA
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34
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Spatial segregation between cell-cell and cell-matrix adhesions. Curr Opin Cell Biol 2012; 24:628-36. [PMID: 22884506 DOI: 10.1016/j.ceb.2012.07.003] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Revised: 06/27/2012] [Accepted: 07/18/2012] [Indexed: 12/18/2022]
Abstract
Cell-cell adhesion (CCA) and cell-matrix adhesion (CMA) play determinant roles in the architecture and function of epithelial cells. CCA and CMA are supported by transmembrane molecular complexes that dynamically interact with the extracellular environment and the cell cytoskeleton. Although those complexes have distinct functions, they are involved in a continuous crosstalk. In epithelia, CCA and CMA segregate in distinct regions of the cell surface and thereby take part in cell polarity. Recent results have shown that the two adhesion systems exert negative feedback on each other and appear to regulate actin network dynamics and mechanical force production in different ways. In light of this, we argue that the interplay between these regulatory mechanisms plays an important role in the spatial separation of cell-cell and cell-matrix adhesions components in distinct regions of the cell surface.
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35
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Tepass U. The apical polarity protein network in Drosophila epithelial cells: regulation of polarity, junctions, morphogenesis, cell growth, and survival. Annu Rev Cell Dev Biol 2012; 28:655-85. [PMID: 22881460 DOI: 10.1146/annurev-cellbio-092910-154033] [Citation(s) in RCA: 258] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Epithelial tissue formation and function requires the apical-basal polarization of individual epithelial cells. Apical polarity regulators (APRs) are an evolutionarily conserved group of key factors that govern polarity and several other aspects of epithelial differentiation. APRs compose a diverse set of molecules including a transmembrane protein (Crumbs), a serine/threonine kinase (aPKC), a lipid phosphatase (PTEN), a small GTPase (Cdc42), FERM domain proteins (Moesin, Yurt), and several adaptor or scaffolding proteins (Bazooka/Par3, Par6, Stardust, Patj). These proteins form a dynamic cooperative network that is engaged in negative-feedback regulation with basolateral polarity factors to set up the epithelial apical-basal axis. APRs support the formation of the apical junctional complex and the segregation of the junctional domain from the apical membrane. It is becoming increasingly clear that APRs interact with the cytoskeleton and vesicle trafficking machinery, regulate morphogenesis, and modulate epithelial cell growth and survival. Not surprisingly, APRs have multiple fundamental links to human diseases such as cancer and blindness.
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Affiliation(s)
- Ulrich Tepass
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario M5S 3G5, Canada.
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36
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Epifano C, Perez-Moreno M. Crossroads of integrins and cadherins in epithelia and stroma remodeling. Cell Adh Migr 2012; 6:261-73. [PMID: 22568988 DOI: 10.4161/cam.20253] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Adhesion events mediated by cadherin and integrin adhesion receptors have fundamental roles in the maintenance of the physiological balance of epithelial tissues, and it is well established that perturbations in their normal functional activity and/or changes in their expression are associated with tumorigenesis. Over the last decades, increasing evidence of a dynamic collaborative interaction between these complexes through their shared interactions with cytoskeletal proteins and common signaling pathways has emerged not only as an important regulator of several aspects of epithelial cell behavior, but also as a coordinated adhesion module that senses and transmits signals from and to the epithelia surrounding microenvironment. The tight regulation of their crosstalk is particularly important during epithelial remodeling events that normally take place during morphogenesis and tissue repair, and when defective it leads to cell transformation and aggravated responses of the tumor microenvironment that contribute to tumorigenesis. In this review we highlight some of the interactions that regulate their crosstalk and how this could be implicated in regulating signals across epithelial tissues to sustain homeostasis.
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Affiliation(s)
- Carolina Epifano
- Epithelial Cell Biology Group, BBVA Foundation-Cancer Cell Biology Programme, Centro Nacional de Investigaciones Oncológicas (CNIO), Madrid, Spain
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37
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New Insights into the Regulation of E-cadherin Distribution by Endocytosis. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2012; 295:63-108. [DOI: 10.1016/b978-0-12-394306-4.00008-3] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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38
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Abstract
Drosophila represents a paradigm for the analysis of the cellular, molecular and genetic mechanisms of development and is an ideal model system to study the contribution of Adherens Junctions (AJs) and their major components, cadherins, to morphogenesis. The combination of different techniques and approaches has allowed researchers to identify the requirements of these epithelial junctions in vivo in the context of a whole organism. The functional analysis of mutants for AJ core components, particularly for Drosophila DE-cadherin, has shown that AJs play critical roles in virtually all stages of development. For instance, AJs maintain tissue integrity while allowing the remodelling and homeostasis of many tissues. They control cell shape, contribute to cell polarity, facilitate cell-cell recognition during cell sorting, orient cell divisions, or regulate cell rearrangements, among other activities. Remarkably, these activities require a very fine control of the organisation and turnover of AJs during development. In addition, AJs engage in diverse and complex interactions with the cytoskeleton, signalling networks, intracellular trafficking machinery or polarity cues to perform these functions. Here, by summarising the requirements of AJs and cadherins during Drosophila morphogenesis, we illustrate the capital contribution of this model system to our knowledge of the mechanisms and biology of AJs.
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Affiliation(s)
- Annalisa Letizia
- Developmental Biology, Institut de Biologia Molecular de Barcelona, CSIC, Parc Científic de Barcelona Baldiri Reixac 10-12, 08028, Barcelona, Spain,
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39
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Weber GF, Bjerke MA, DeSimone DW. Integrins and cadherins join forces to form adhesive networks. J Cell Sci 2011; 124:1183-93. [PMID: 21444749 DOI: 10.1242/jcs.064618] [Citation(s) in RCA: 254] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Cell-cell and cell-extracellular-matrix (cell-ECM) adhesions have much in common, including shared cytoskeletal linkages, signaling molecules and adaptor proteins that serve to regulate multiple cellular functions. The term 'adhesive crosstalk' is widely used to indicate the presumed functional communication between distinct adhesive specializations in the cell. However, this distinction is largely a simplification on the basis of the non-overlapping subcellular distribution of molecules that are involved in adhesion and adhesion-dependent signaling at points of cell-cell and cell-substrate contact. The purpose of this Commentary is to highlight data that demonstrate the coordination and interdependence of cadherin and integrin adhesions. We describe the convergence of adhesive inputs on cell signaling pathways and cytoskeletal assemblies involved in regulating cell polarity, migration, proliferation and survival, differentiation and morphogenesis. Cell-cell and cell-ECM adhesions represent highly integrated networks of protein interactions that are crucial for tissue homeostasis and the responses of individual cells to their adhesive environments. We argue that the machinery of adhesion in multicellular tissues comprises an interdependent network of cell-cell and cell-ECM interactions and signaling responses, and not merely crosstalk between spatially and functionally distinct adhesive specializations within cells.
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Affiliation(s)
- Gregory F Weber
- Department of Cell Biology, School of Medicine, University of Virginia Health System, Charlottesville, VA 22908, USA
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40
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Willin and Par3 cooperatively regulate epithelial apical constriction through aPKC-mediated ROCK phosphorylation. Nat Cell Biol 2011; 13:860-6. [PMID: 21685893 DOI: 10.1038/ncb2274] [Citation(s) in RCA: 97] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2010] [Accepted: 05/06/2011] [Indexed: 12/16/2022]
Abstract
Apical-domain constriction is important for regulating epithelial morphogenesis. Epithelial cells are connected by apical junctional complexes (AJCs) that are lined with circumferential actomyosin cables. The contractility of these cables is regulated by Rho-associated kinases (ROCKs). Here, we report that Willin (a FERM-domain protein) and Par3 (a polarity-regulating protein) cooperatively regulate ROCK-dependent apical constriction. We found that Willin recruits aPKC and Par6 to the AJCs, independently of Par3. Simultaneous depletion of Willin and Par3 completely removed aPKC and Par6 from the AJCs and induced apical constriction. Induced constriction was through upregulation of the level of AJC-associated ROCKs, which was due to loss of aPKC. Our results indicate that aPKC phosphorylates ROCK and suppresses its junctional localization, thereby allowing cells to retain normally shaped apical domains. Thus, we have uncovered a Willin/Par3-aPKC-ROCK pathway that controls epithelial apical morphology.
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41
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Baum B, Georgiou M. Dynamics of adherens junctions in epithelial establishment, maintenance, and remodeling. ACTA ACUST UNITED AC 2011; 192:907-17. [PMID: 21422226 PMCID: PMC3063136 DOI: 10.1083/jcb.201009141] [Citation(s) in RCA: 370] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The epithelial cadherin (E-cadherin)–catenin complex binds to cytoskeletal components and regulatory and signaling molecules to form a mature adherens junction (AJ). This dynamic structure physically connects neighboring epithelial cells, couples intercellular adhesive contacts to the cytoskeleton, and helps define each cell’s apical–basal axis. Together these activities coordinate the form, polarity, and function of all cells in an epithelium. Several molecules regulate AJ formation and integrity, including Rho family GTPases and Par polarity proteins. However, only recently, with the development of live-cell imaging, has the extent to which E-cadherin is actively turned over at junctions begun to be appreciated. This turnover contributes to junction formation and to the maintenance of epithelial integrity during tissue homeostasis and remodeling.
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Affiliation(s)
- Buzz Baum
- University College London, London WC1E 6BT, England, UK
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Vlachos S, Harden N. Genetic evidence for antagonism between Pak protein kinase and Rho1 small GTPase signaling in regulation of the actin cytoskeleton during Drosophila oogenesis. Genetics 2011; 187:501-12. [PMID: 21098722 PMCID: PMC3030492 DOI: 10.1534/genetics.110.120998] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2010] [Accepted: 11/18/2010] [Indexed: 12/15/2022] Open
Abstract
During Drosophila oogenesis, basally localized F-actin bundles in the follicle cells covering the egg chamber drive its elongation along the anterior-posterior axis. The basal F-actin of the follicle cell is an attractive system for the genetic analysis of the regulation of the actin cytoskeleton, and results obtained in this system are likely to be broadly applicable in understanding tissue remodeling. Mutations in a number of genes, including that encoding the p21-activated kinase Pak, have been shown to disrupt organization of the basal F-actin and in turn affect egg chamber elongation. pak mutant egg chambers have disorganized F-actin distribution and remain spherical due to a failure to elongate. In a genetic screen to identify modifiers of the pak rounded egg chamber phenotype several second chromosome deficiencies were identified as suppressors. One suppressing deficiency removes the rho1 locus, and we determined using several rho1 alleles that removal of a single copy of rho1 can suppress the pak phenotype. Reduction of any component of the Rho1-activated actomyosin contractility pathway suppresses pak oogenesis defects, suggesting that Pak counteracts Rho1 signaling. There is ectopic myosin light chain phosphorylation in pak mutant follicle cell clones in elongating egg chambers, probably due at least in part to mislocalization of RhoGEF2, an activator of the Rho1 pathway. In early egg chambers, pak mutant follicle cells have reduced levels of myosin phosphorylation and we conclude that Pak both promotes and restricts myosin light chain phosphorylation in a temporally distinct manner during oogenesis.
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Affiliation(s)
| | - Nicholas Harden
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia, V5A 1S6, Canada
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Sandquist JC, Bement WM. Hold on tightly, let go lightly: myosin functions at adherens junctions. Nat Cell Biol 2010; 12:633-5. [PMID: 20596044 DOI: 10.1038/ncb0710-633] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Adherens junctions, the sites of cadherin-dependent cell-cell adhesion, are also important for dynamic tension sensing, force transduction and signalling. Different myosin motors contribute to adherens junction assembly and versatility in distinct ways.
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Harris TJC, Tepass U. Adherens junctions: from molecules to morphogenesis. Nat Rev Mol Cell Biol 2010; 11:502-14. [PMID: 20571587 DOI: 10.1038/nrm2927] [Citation(s) in RCA: 678] [Impact Index Per Article: 48.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
How adhesive interactions between cells generate and maintain animal tissue structure remains one of the most challenging and long-standing questions in cell and developmental biology. Adherens junctions (AJs) and the cadherin-catenin complexes at their core are therefore the subjects of intense research. Recent work has greatly advanced our understanding of the molecular organization of AJs and how cadherin-catenin complexes engage actin, microtubules and the endocytic machinery. As a result, we have gained important insights into the molecular mechanisms of tissue morphogenesis.
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Affiliation(s)
- Tony J C Harris
- Department of Cell and Systems Biology, University of Toronto, 25 Harbord Street, Toronto, Ontario M5S 3G5, Canada.
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Warner SJ, Yashiro H, Longmore GD. The Cdc42/Par6/aPKC polarity complex regulates apoptosis-induced compensatory proliferation in epithelia. Curr Biol 2010; 20:677-86. [PMID: 20381350 DOI: 10.1016/j.cub.2010.03.025] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2009] [Revised: 03/12/2010] [Accepted: 03/12/2010] [Indexed: 11/26/2022]
Abstract
BACKGROUND In response to stress- or tissue-damage-induced apoptosis, unaffected epithelial cells undergo compensatory proliferation to maintain the integrity of the epithelium. Proximal signals regulating this response are not fully understood, but c-Jun N-terminal kinase (JNK) activity appears to be critical for both apoptosis and compensatory proliferation. Disruption of epithelial cell apical-basal polarity occurs in early cancer development and is often correlated with increased proliferation by means not fully characterized. We considered whether disruption of the various polarity complexes could provide signals identifying damaged epithelial cells and thus lead to apoptosis-induced compensatory proliferation. RESULTS We identify the Cdc42/Par6/atypical protein kinase C (aPKC) Par polarity complex as uniquely and specifically regulating apoptosis-induced compensatory proliferation in Drosophila epithelia. Genetic depletion of individual components or disruption of formation and localization of this complex, but not other polarity complexes, induces JNK-dependent apoptosis and JNK-dependent compensatory proliferation following radiation injury. When apoptosis execution is blocked, by p35 expression, Cdc42/Par6/aPKC-depleted tissues uniquely hyperproliferate, leading to tissue and organ overgrowth. Disruption of Cdc42/Par6/aPKC leads to activation of JNK through increased Rho1 and Rok activity and Rok's capacity to activate myosin but not F-actin. CONCLUSIONS We show that the Cdc42/Par6/aPKC polarity complex influences both a physiologic compensatory proliferation response after irradiation injury and a contrived compensatory non-cell-autonomous hyperproliferation response when cell-autonomous apoptosis, resulting from Cdc42/Par6/aPKC disruption, is inhibited. These results suggest the possibility that in cancer where apoptotic regulation is disrupted, loss of Cdc42/Par6/aPKC polarity complex organization or localization could contribute to tumor hyperproliferation and explain how polarity disruption contributes to tumor development.
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Affiliation(s)
- Stephen J Warner
- Department of Medicine, BRIGHT Institute, Washington University School of Medicine, St. Louis, MO 63110, USA
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Abstract
Cells are sequentially recruited during formation of the Drosophila compound eye. A few simple rules are reiteratively utilized to control successive steps of eye assembly. Two themes emerge: the interplay between cell signaling and competence determines diversity of cell types and selective cell adhesion determines spatial patterns of cells. Cell signaling through competence creates signaling relays, which sequentially trigger differentiation of all cell types. Selective cell adhesion, on the other hand, provides forces to drive cells into energy-favored spatial configurations. Organ formation is nevertheless a complex process. The complexity lies in the spatial, temporal, and quantitative precision of gene expression. Many challenging questions remain.
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Affiliation(s)
- Sujin Bao
- Department of Pediatrics, Mount Sinai School of Medicine, New York, USA
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Sawyer JK, Harris NJ, Peifer M. Morphogenesis: Multitalented GTPases Seeking New Jobs. Curr Biol 2009; 19:R985-7. [DOI: 10.1016/j.cub.2009.09.060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Roeth JF, Sawyer JK, Wilner DA, Peifer M. Rab11 helps maintain apical crumbs and adherens junctions in the Drosophila embryonic ectoderm. PLoS One 2009; 4:e7634. [PMID: 19862327 PMCID: PMC2763285 DOI: 10.1371/journal.pone.0007634] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2009] [Accepted: 10/07/2009] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Tissue morphogenesis and organogenesis require that cells retain stable cell-cell adhesion while changing shape and moving. One mechanism to accommodate this plasticity in cell adhesion involves regulated trafficking of junctional proteins. METHODOLOGY/PRINCIPAL FINDINGS Here we explored trafficking of junctional proteins in two well-characterized model epithelia, the Drosophila embryonic ectoderm and amnioserosa. We find that DE-cadherin, the transmembrane protein of adherens junctions, is actively trafficked through putative vesicles, and appears to travel through both Rab5-positive and Rab11-positive structures. We manipulated the functions of Rab11 and Rab5 to examine the effects on junctional stability and morphogenesis. Reducing Rab11 function, either using a dominant negative construct or loss of function alleles, disrupts integrity of the ectoderm and leads to loss of adherens junctions. Strikingly, the apical junctional regulator Crumbs is lost before AJs are destabilized, while the basolateral protein Dlg remains cortical. Altering Rab5 function had less dramatic effects, not disrupting adherens junction integrity but affecting dorsal closure. CONCLUSIONS/SIGNIFICANCE We contrast our results with what others saw when disrupting other trafficking regulators, and when disrupting Rab function in other tissues; together these data suggest distinct mechanisms regulate junctional stability and plasticity in different tissues.
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Affiliation(s)
- Jeremiah F. Roeth
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Jessica K. Sawyer
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Daniel A. Wilner
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Mark Peifer
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- * E-mail:
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