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Ivanov AI, Lechuga S, Marino‐Melendez A, Naydenov NG. Unique and redundant functions of cytoplasmic actins and nonmuscle myosin II isoforms at epithelial junctions. Ann N Y Acad Sci 2022; 1515:61-74. [PMID: 35673768 PMCID: PMC9489603 DOI: 10.1111/nyas.14808] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The integrity and functions of epithelial barriers depend on the formation of adherens junctions (AJs) and tight junctions (TJs). A characteristic feature of AJs and TJs is their association with the cortical cytoskeleton composed of actin filaments and nonmuscle myosin II (NM-II) motors. Mechanical forces generated by the actomyosin cytoskeleton are essential for junctional assembly, stability, and remodeling. Epithelial cells express two different actin proteins and three NM-II isoforms, all known to be associated with AJs and TJs. Despite their structural similarity, different actin and NM-II isoforms have distinct biochemical properties, cellular distribution, and functions. The diversity of epithelial actins and myosin motors could be essential for the regulation of different steps of junctional formation, maturation, and disassembly. This review focuses on the roles of actin and NM-II isoforms in controlling the integrity and barrier properties of various epithelia. We discuss the effects of the depletion of individual actin isoforms and NM-II motors on the assembly and barrier function of AJs and TJs in model epithelial monolayers in vitro. We also describe the functional consequences of either total or tissue-specific gene knockout of different actins and NM-II motors, with a focus on the development and integrity of different epithelia in vivo.
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Affiliation(s)
- Andrei I. Ivanov
- Department of Inflammation and Immunity, Lerner Research InstituteCleveland ClinicClevelandOhioUSA
| | - Susana Lechuga
- Department of Inflammation and Immunity, Lerner Research InstituteCleveland ClinicClevelandOhioUSA
| | - Armando Marino‐Melendez
- Department of Inflammation and Immunity, Lerner Research InstituteCleveland ClinicClevelandOhioUSA
| | - Nayden G. Naydenov
- Department of Inflammation and Immunity, Lerner Research InstituteCleveland ClinicClevelandOhioUSA
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Jones MR, Chong L, Bellusci S. Fgf10/Fgfr2b Signaling Orchestrates the Symphony of Molecular, Cellular, and Physical Processes Required for Harmonious Airway Branching Morphogenesis. Front Cell Dev Biol 2021; 8:620667. [PMID: 33511132 PMCID: PMC7835514 DOI: 10.3389/fcell.2020.620667] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 12/10/2020] [Indexed: 12/12/2022] Open
Abstract
Airway branching morphogenesis depends on the intricate orchestration of numerous biological and physical factors connected across different spatial scales. One of the key regulatory pathways controlling airway branching is fibroblast growth factor 10 (Fgf10) signaling via its epithelial fibroblast growth factor receptor 2b (Fgfr2b). Fine reviews have been published on the molecular mechanisms, in general, involved in branching morphogenesis, including those mechanisms, in particular, connected to Fgf10/Fgfr2b signaling. However, a comprehensive review looking at all the major biological and physical factors involved in branching, at the different scales at which branching operates, and the known role of Fgf10/Fgfr2b therein, is missing. In the current review, we attempt to summarize the existing literature on airway branching morphogenesis by taking a broad approach. We focus on the biophysical and mechanical forces directly shaping epithelial bud initiation, branch elongation, and branch tip bifurcation. We then shift focus to more passive means by which branching proceeds, via extracellular matrix remodeling and the influence of the other pulmonary arborized networks: the vasculature and nerves. We end the review by briefly discussing work in computational modeling of airway branching. Throughout, we emphasize the known or speculative effects of Fgfr2b signaling at each point of discussion. It is our aim to promote an understanding of branching morphogenesis that captures the multi-scalar biological and physical nature of the phenomenon, and the interdisciplinary approach to its study.
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Affiliation(s)
- Matthew R. Jones
- Key Laboratory of Interventional Pulmonology of Zhejiang Province, Department of Pulmonary and Critical Care Medicine, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
- Cardio-Pulmonary Institute and Department of Pulmonary and Critical Care Medicine and Infectious Diseases, Universities of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Justus-Liebig University Giessen, Giessen, Germany
| | - Lei Chong
- National Key Clinical Specialty of Pediatric Respiratory Medicine, Discipline of Pediatric Respiratory Medicine, Institute of Pediatrics, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
| | - Saverio Bellusci
- Key Laboratory of Interventional Pulmonology of Zhejiang Province, Department of Pulmonary and Critical Care Medicine, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
- Cardio-Pulmonary Institute and Department of Pulmonary and Critical Care Medicine and Infectious Diseases, Universities of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Justus-Liebig University Giessen, Giessen, Germany
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Huang L, Yuan W, Hong Y, Fan S, Yao X, Ren T, Song L, Yang G, Zhang Y. 3D printed hydrogels with oxidized cellulose nanofibers and silk fibroin for the proliferation of lung epithelial stem cells. CELLULOSE (LONDON, ENGLAND) 2021; 28:241-257. [PMID: 33132545 PMCID: PMC7590576 DOI: 10.1007/s10570-020-03526-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Accepted: 10/10/2020] [Indexed: 05/06/2023]
Abstract
A novel biomaterial ink consisting of regenerated silk fibroin (SF) and 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized bacterial cellulose (OBC) nanofibrils was developed for 3D printing lung tissue scaffold. Silk fibroin backbones were cross-linked using horseradish peroxide/H2O2 to form printed hydrogel scaffolds. OBC with a concentration of 7wt% increased the viscosity of inks during the printing process and further improved the shape fidelity of the scaffolds. Rheological measurements and image analyses were performed to evaluate inks printability and print shape fidelity. Three-dimensional construct with ten layers could be printed with ink of 1SF-2OBC (SF/OBC = 1/2, w/w). The composite hydrogel of 1SF-1OBC (SF/OBC = 1/1, w/w) printed at 25 °C exhibited a significantly improved compressive strength of 267 ± 13 kPa and a compressive stiffness of 325 ± 14 kPa at 30% strain, respectively. The optimized printing parameters for 1SF-1OBC were 0.3 bar of printing pressure, 45 mm/s of printing speed and 410 μm of nozzle diameter. Furthermore, OBC nanofibrils could be induced to align along the print lines over 60% degree of orientation, which were analyzed by SEM and X-ray diffraction. The orientation of OBC nanofibrils along print lines provided physical cues for guiding the orientation of lung epithelial stem cells, which maintained the ability to proliferate and kept epithelial phenotype after 7 days' culture. The 3D printed SF-OBC scaffolds are promising for applications in lung tissue engineering.
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Affiliation(s)
- Li Huang
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Shanghai Belt and Road Joint Laboratory of Advanced Fiber and Low-Dimension Materials, College of Materials Science and Engineering, Donghua University, Shanghai, 201620 People’s Republic of China
| | - Wei Yuan
- Department of Urology, Weifang People’s Hospital, Weifang Medical University, Weifang, 261000 Shandong People’s Republic of China
| | - Yue Hong
- Department of Respiratory Medicine, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, 200233 People’s Republic of China
| | - Suna Fan
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Shanghai Belt and Road Joint Laboratory of Advanced Fiber and Low-Dimension Materials, College of Materials Science and Engineering, Donghua University, Shanghai, 201620 People’s Republic of China
| | - Xiang Yao
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Shanghai Belt and Road Joint Laboratory of Advanced Fiber and Low-Dimension Materials, College of Materials Science and Engineering, Donghua University, Shanghai, 201620 People’s Republic of China
| | - Tao Ren
- Department of Respiratory Medicine, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, 200233 People’s Republic of China
| | - Lujie Song
- Department of Urology, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, 200233 People’s Republic of China
- Shanghai Oriental Institute for Urologic Reconstruction, Shanghai, 200233 People’s Republic of China
| | - Gesheng Yang
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Shanghai Belt and Road Joint Laboratory of Advanced Fiber and Low-Dimension Materials, College of Materials Science and Engineering, Donghua University, Shanghai, 201620 People’s Republic of China
| | - Yaopeng Zhang
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Shanghai Belt and Road Joint Laboratory of Advanced Fiber and Low-Dimension Materials, College of Materials Science and Engineering, Donghua University, Shanghai, 201620 People’s Republic of China
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Noncanonical Wnt planar cell polarity signaling in lung development and disease. Biochem Soc Trans 2020; 48:231-243. [PMID: 32096543 DOI: 10.1042/bst20190597] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 01/24/2020] [Accepted: 01/28/2020] [Indexed: 02/06/2023]
Abstract
The planar cell polarity (PCP) signaling pathway is a potent developmental regulator of directional cell behaviors such as migration, asymmetric division and morphological polarization that are critical for shaping the body axis and the complex three-dimensional architecture of tissues and organs. PCP is considered a noncanonical Wnt pathway due to the involvement of Wnt ligands and Frizzled family receptors in the absence of the beta-catenin driven gene expression observed in the canonical Wnt cascade. At the heart of the PCP mechanism are protein complexes capable of generating molecular asymmetries within cells along a tissue-wide axis that are translated into polarized actin and microtubule cytoskeletal dynamics. PCP has emerged as an important regulator of developmental, homeostatic and disease processes in the respiratory system. It acts along other signaling pathways to create the elaborately branched structure of the lung by controlling the directional protrusive movements of cells during branching morphogenesis. PCP operates in the airway epithelium to establish and maintain the orientation of respiratory cilia along the airway axis for anatomically directed mucociliary clearance. It also regulates the establishment of the pulmonary vasculature. In adult tissues, PCP dysfunction has been linked to a variety of chronic lung diseases such as cystic fibrosis, chronic obstructive pulmonary disease, and idiopathic pulmonary arterial hypertension, stemming chiefly from the breakdown of proper tissue structure and function and aberrant cell migration during regenerative wound healing. A better understanding of these (impaired) PCP mechanisms is needed to fully harness the therapeutic opportunities of targeting PCP in chronic lung diseases.
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Li X, Liu H, Yu W, Liu X, Liu C. Tandem mass tag (TMT) proteomic analysis of fetal lungs revealed differential expression of tight junction proteins in a rat model of congenital diaphragmatic hernia. Biomed Pharmacother 2019; 121:109621. [PMID: 31734580 DOI: 10.1016/j.biopha.2019.109621] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 11/01/2019] [Accepted: 11/01/2019] [Indexed: 02/04/2023] Open
Abstract
OBJECTIVE Congenital diaphragmatic hernia (CDH) is a common and often lethal birth defect characterized by congenital lung malformation, which severely affects neonate prognosis and mortality. This study aimed to investigate differences in protein expression in order to elucidate the mechanism of CDH-associated pulmonary hypoplasia during the early stage of lung development using tandem mass tag (TMT) quantitative proteomics. METHODS Nitrofen was administered orally to establish a rat CDH model, and pathological changes were evaluated through hematoxylin-eosin (H&E), PCNA, and Ki67 staining at the pseudoglandular stage. Fetal lungs were then collected, pooled before TMT labeling, and subjected to mass spectrometry. Immunohistochemistry (IHC), Western blotting, and Q-PCR were used to further validate the candidate proteins. RESULTS A total of 79 differentially expressed proteins (DEPs) were identified when CDH and control lungs were compared, and further bioinformatics analysis showed that these proteins play important roles in tight-junctions, phospholipase D signaling, and the HIF-1 signaling pathway. Three differentially expressed proteins, Cldn3, Magi1, and Myh9 are involved in the tight-junction pathway (P < 0.05), and their differential expressions were confirmed by IHC, Western blotting, and Q-PCR. CONCLUSION These findings indicate that alterations of tight-junction protein expression may play an important role in the pathogenesis of abnormal lung development in CDH. Further studies are warranted to verify the mechanism by which these tight-junction proteins influence the pathogenesis of CDH-associated pulmonary hypoplasia.
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Affiliation(s)
- Xue Li
- Department of Gynecology and Obstetrics, Shengjing Hospital of China Medical University, Shenyang, China; Key Laboratory of Maternal-Fetal Medicine of Liaoning Province, Benxi, China.
| | - Hao Liu
- Department of Gynecology and Obstetrics, Shengjing Hospital of China Medical University, Shenyang, China; Key Laboratory of Maternal-Fetal Medicine of Liaoning Province, Benxi, China.
| | - Wenqian Yu
- Department of Gynecology and Obstetrics, Shengjing Hospital of China Medical University, Shenyang, China; Key Laboratory of Maternal-Fetal Medicine of Liaoning Province, Benxi, China.
| | - Xiaomei Liu
- Department of Gynecology and Obstetrics, Shengjing Hospital of China Medical University, Shenyang, China; Key Laboratory of Maternal-Fetal Medicine of Liaoning Province, Benxi, China.
| | - Caixia Liu
- Department of Gynecology and Obstetrics, Shengjing Hospital of China Medical University, Shenyang, China; Key Laboratory of Maternal-Fetal Medicine of Liaoning Province, Benxi, China.
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Kim HT, Yin W, Jin YJ, Panza P, Gunawan F, Grohmann B, Buettner C, Sokol AM, Preussner J, Guenther S, Kostin S, Ruppert C, Bhagwat AM, Ma X, Graumann J, Looso M, Guenther A, Adelstein RS, Offermanns S, Stainier DYR. Myh10 deficiency leads to defective extracellular matrix remodeling and pulmonary disease. Nat Commun 2018; 9:4600. [PMID: 30389913 PMCID: PMC6214918 DOI: 10.1038/s41467-018-06833-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Accepted: 09/25/2018] [Indexed: 01/18/2023] Open
Abstract
Impaired alveolar formation and maintenance are features of many pulmonary diseases that are associated with significant morbidity and mortality. In a forward genetic screen for modulators of mouse lung development, we identified the non-muscle myosin II heavy chain gene, Myh10. Myh10 mutant pups exhibit cyanosis and respiratory distress, and die shortly after birth from differentiation defects in alveolar epithelium and mesenchyme. From omics analyses and follow up studies, we find decreased Thrombospondin expression accompanied with increased matrix metalloproteinase activity in both mutant lungs and cultured mutant fibroblasts, as well as disrupted extracellular matrix (ECM) remodeling. Loss of Myh10 specifically in mesenchymal cells results in ECM deposition defects and alveolar simplification. Notably, MYH10 expression is downregulated in the lung of emphysema patients. Altogether, our findings reveal critical roles for Myh10 in alveologenesis at least in part via the regulation of ECM remodeling, which may contribute to the pathogenesis of emphysema.
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Affiliation(s)
- Hyun-Taek Kim
- Department of Developmental Genetics, Max Planck Institute for Heart and Lung Research, Bad Nauheim, 61231, Germany.
| | - Wenguang Yin
- Department of Developmental Genetics, Max Planck Institute for Heart and Lung Research, Bad Nauheim, 61231, Germany
| | - Young-June Jin
- Department of Pharmacology, Max Planck Institute for Heart and Lung Research, Bad Nauheim, 61231, Germany
| | - Paolo Panza
- Department of Developmental Genetics, Max Planck Institute for Heart and Lung Research, Bad Nauheim, 61231, Germany
| | - Felix Gunawan
- Department of Developmental Genetics, Max Planck Institute for Heart and Lung Research, Bad Nauheim, 61231, Germany
| | - Beate Grohmann
- Department of Developmental Genetics, Max Planck Institute for Heart and Lung Research, Bad Nauheim, 61231, Germany
| | - Carmen Buettner
- Department of Developmental Genetics, Max Planck Institute for Heart and Lung Research, Bad Nauheim, 61231, Germany
| | - Anna M Sokol
- Scientific Service Group of Biomolecular Mass Spectrometry, Max Planck Institute for Heart and Lung Research, Bad Nauheim, 61231, Germany
| | - Jens Preussner
- ECCPS Bioinformatics and Deep Sequencing Platform, Max Planck Institute for Heart and Lung Research, Bad Nauheim, 61231, Germany
| | - Stefan Guenther
- ECCPS Bioinformatics and Deep Sequencing Platform, Max Planck Institute for Heart and Lung Research, Bad Nauheim, 61231, Germany
| | - Sawa Kostin
- Scientific Service Group of Morphometry, Max Planck Institute for Heart and Lung Research, Bad Nauheim, 61231, Germany
| | - Clemens Ruppert
- Biobank, University of Giessen & Marburg Lung Center (UGLMC), Giessen, 35392, Germany
| | - Aditya M Bhagwat
- Bioinformatics Core, Weill Cornell Medicine - Qatar, Doha, PO 24144, Qatar
| | - Xuefei Ma
- Laboratory of Molecular Cardiology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20814, USA
| | - Johannes Graumann
- Scientific Service Group of Biomolecular Mass Spectrometry, Max Planck Institute for Heart and Lung Research, Bad Nauheim, 61231, Germany
- German Centre for Cardiovascular Research (DZHK), Partner Site Rhine-Main, Frankfurt, 60323, Germany
| | - Mario Looso
- ECCPS Bioinformatics and Deep Sequencing Platform, Max Planck Institute for Heart and Lung Research, Bad Nauheim, 61231, Germany
| | - Andreas Guenther
- Biobank, University of Giessen & Marburg Lung Center (UGLMC), Giessen, 35392, Germany
| | - Robert S Adelstein
- Laboratory of Molecular Cardiology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20814, USA
| | - Stefan Offermanns
- Department of Pharmacology, Max Planck Institute for Heart and Lung Research, Bad Nauheim, 61231, Germany
- German Centre for Cardiovascular Research (DZHK), Partner Site Rhine-Main, Frankfurt, 60323, Germany
| | - Didier Y R Stainier
- Department of Developmental Genetics, Max Planck Institute for Heart and Lung Research, Bad Nauheim, 61231, Germany.
- German Centre for Cardiovascular Research (DZHK), Partner Site Rhine-Main, Frankfurt, 60323, Germany.
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Haque F, Kaku Y, Fujimura S, Ohmori T, Adelstein RS, Nishinakamura R. Non-muscle myosin II deletion in the developing kidney causes ureter-bladder misconnection and apical extrusion of the nephric duct lineage epithelia. Dev Biol 2017; 427:121-130. [PMID: 28478097 DOI: 10.1016/j.ydbio.2017.04.020] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 04/27/2017] [Accepted: 04/29/2017] [Indexed: 01/23/2023]
Abstract
In kidney development, connection of the nephric duct (ND) to the cloaca and subsequent sprouting of the ureteric bud (UB) from the ND are important for urinary exit tract formation. Although the roles of Ret signaling are well established, it remains unclear how intracellular cytoskeletal proteins regulate these morphogenetic processes. Myh9 and Myh10 encode two different non-muscle myosin II heavy chains, and Myh9 mutations in humans are implicated in congenital kidney diseases. Here we report that ND/UB lineage-specific deletion of Myh9/Myh10 in mice caused severe hydroureter/hydronephrosis at birth. At mid-gestation, the mutant ND/UB epithelia exhibited aberrant basal protrusion and ectopic UB formation, which likely led to misconnection of the ureter to the bladder. In addition, the mutant epithelia exhibited apical extrusion followed by massive apoptosis in the lumen, which could be explained by reduced apical constriction and intercellular adhesion mediated by E-cadherin. These phenotypes were not ameliorated by genetic reduction of the tyrosine kinase receptor Ret. In contrast, ERK was activated in the mutant cells and its chemical inhibition partially ameliorated the phenotypes. Thus, myosin II is essential for maintaining the apicobasal integrity of the developing kidney epithelia independently of Ret signaling.
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Affiliation(s)
- Fahim Haque
- Department of Kidney Development, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, Japan
| | - Yusuke Kaku
- Department of Kidney Development, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, Japan
| | - Sayoko Fujimura
- Liaison Laboratory Research Promotion Center, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, Japan
| | - Tomoko Ohmori
- Department of Kidney Development, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, Japan
| | - Robert S Adelstein
- Laboratory of Molecular Cardiology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Ryuichi Nishinakamura
- Department of Kidney Development, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, Japan.
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Gredler ML, Seifert AW, Cohn MJ. Tissue-specific roles of Fgfr2 in development of the external genitalia. Development 2015; 142:2203-12. [PMID: 26081573 DOI: 10.1242/dev.119891] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Congenital anomalies frequently occur in organs that undergo tubulogenesis. Hypospadias is a urethral tube defect defined by mislocalized, oversized, or multiple openings of the penile urethra. Deletion of Fgfr2 or its ligand Fgf10 results in severe hypospadias in mice, in which the entire urethral plate is open along the ventral side of the penis. In the genital tubercle, the embryonic precursor of the penis and clitoris, Fgfr2 is expressed in two epithelial populations: the endodermally derived urethral epithelium and the ectodermally derived surface epithelium. Here, we investigate the tissue-specific roles of Fgfr2 in external genital development by generating conditional deletions of Fgfr2 in each of these cell types. Conditional deletion of Fgfr2 results in two distinct phenotypes: endodermal Fgfr2 deletion causes mild hypospadias and inhibits maturation of a complex urethral epithelium, whereas loss of ectodermal Fgfr2 results in severe hypospadias and absence of the ventral prepuce. Although these cell type-specific mutants exhibit distinctive genital anomalies, cellular analysis reveals that Fgfr2 regulates epithelial maturation and cell cycle progression in the urethral endoderm and in the surface ectoderm. The unexpected finding that ectodermal deletion of Fgfr2 results in the most severe hypospadias highlights a major role for Fgfr2 in the developing genital surface epithelium, where epithelial maturation is required for maintenance of a closed urethral tube. These results demonstrate that urethral tubulogenesis, prepuce morphogenesis, and sexually dimorphic patterning of the lower urethra are controlled by discrete regions of Fgfr2 activity.
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Affiliation(s)
- Marissa L Gredler
- Department of Biology, UF Genetics Institute, University of Florida, PO Box 103610, Gainesville, FL 32611, USA
| | - Ashley W Seifert
- Department of Biology, UF Genetics Institute, University of Florida, PO Box 103610, Gainesville, FL 32611, USA
| | - Martin J Cohn
- Department of Biology, UF Genetics Institute, University of Florida, PO Box 103610, Gainesville, FL 32611, USA Howard Hughes Medical Institute, Department of Molecular Genetics and Microbiology, University of Florida, PO Box 103610, Gainesville, FL 32611, USA
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Hsu JC, Koo H, Harunaga JS, Matsumoto K, Doyle AD, Yamada KM. Region-specific epithelial cell dynamics during branching morphogenesis. Dev Dyn 2013; 242:1066-77. [PMID: 23780688 DOI: 10.1002/dvdy.24000] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2013] [Revised: 06/06/2013] [Accepted: 06/07/2013] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND Epithelial cells of developing embryonic organs, such as salivary glands, can display substantial motility during branching morphogenesis. Their dynamic movements and molecules involved in their migration are not fully characterized. RESULTS We generated transgenic mice expressing photo-convertible KikGR and tracked the movements of individual cells highlighted by red fluorescence in different regions of developing salivary glands. Motility was highest for outer bud epithelial cells adjacent to the basement membrane, lower in inner bud cells, and lowest in duct cells. The highly motile outer cells contacting the basement membrane were pleomorphic, whereas inner cells were rounded. Peripheral cell motility was disrupted by antibodies inhibiting α6+β1 integrins and the nonmuscle myosin II inhibitor blebbistatin. Inner bud cell migration was unaffected by these inhibitors, but their rate of migration was stimulated by inhibiting E-cadherin. CONCLUSIONS Cell motility in developing salivary glands was highest in cells in contact with the basement membrane. The basement membrane-associated motility of these outer bud cells depended on integrins and myosin II, but not E-cadherin. In contrast, motility of inner bud cells was restrained by E-cadherin. These findings identify the importance of integrin-dependent basement membrane association for the morphology, tissue organization, and lateral motility of morphogenetic epithelial cells.
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Affiliation(s)
- Jeff C Hsu
- Cell Biology Section, Laboratory of Cell and Developmental Biology, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland, USA
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