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Sugiyama Y, Reed DA, Herrmann D, Lovicu FJ, Robinson ML, Timpson P, Masai I. Fibroblast growth factor-induced lens fiber cell elongation is driven by the stepwise activity of Rho and Rac. Development 2024; 151:dev202123. [PMID: 38240393 PMCID: PMC10911273 DOI: 10.1242/dev.202123] [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: 06/27/2023] [Accepted: 01/09/2024] [Indexed: 01/30/2024]
Abstract
The spheroidal shape of the eye lens is crucial for precise light focusing onto the retina. This shape is determined by concentrically aligned, convexly elongated lens fiber cells along the anterior and posterior axis of the lens. Upon differentiation at the lens equator, the fiber cells increase in height as their apical and basal tips migrate towards the anterior and posterior poles, respectively. The forces driving this elongation and migration remain unclear. We found that, in the mouse lens, membrane protrusions or lamellipodia are observed only in the maturing fibers undergoing cell curve conversion, indicating that lamellipodium formation is not the primary driver of earlier fiber migration. We demonstrated that elevated levels of fibroblast growth factor (FGF) suppressed the extension of Rac-dependent protrusions, suggesting changes in the activity of FGF controlling Rac activity, switching to lamellipodium-driven migration. Inhibitors of ROCK, myosin and actin reduced the height of both early and later fibers, indicating that elongation of these fibers relies on actomyosin contractility. Consistent with this, active RhoA was detected throughout these fibers. Given that FGF promotes fiber elongation, we propose that it does so through regulation of Rho activity.
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Affiliation(s)
- Yuki Sugiyama
- Developmental Neurobiology Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa 904-0495, Japan
- Save Sight Institute, The University of Sydney, Sydney, NSW 2000, Australia
| | - Daniel A. Reed
- Cancer Ecosystems Program, The Garvan Institute of Medical Research & The Kinghorn Cancer Centre, St Vincent's Clinical School, Faculty of Medicine, UNSW Sydney, Sydney, NSW 2010, Australia
| | - David Herrmann
- Cancer Ecosystems Program, The Garvan Institute of Medical Research & The Kinghorn Cancer Centre, St Vincent's Clinical School, Faculty of Medicine, UNSW Sydney, Sydney, NSW 2010, Australia
| | - Frank J. Lovicu
- Save Sight Institute, The University of Sydney, Sydney, NSW 2000, Australia
- Molecular and Cellular Biomedicine, School of Medical Sciences, The University of Sydney, Sydney, NSW 2006, Australia
| | - Michael L. Robinson
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH 45056, USA
| | - Paul Timpson
- Cancer Ecosystems Program, The Garvan Institute of Medical Research & The Kinghorn Cancer Centre, St Vincent's Clinical School, Faculty of Medicine, UNSW Sydney, Sydney, NSW 2010, Australia
| | - Ichiro Masai
- Developmental Neurobiology Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa 904-0495, Japan
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2
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Sugiyama Y, Reed DA, Herrmann D, Lovicu FJ, Robinson ML, Timpson P, Masai I. Fibroblast Growth Factor-induced lens fiber cell elongation is driven by the stepwise activity of Rho and Rac. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.03.569812. [PMID: 38106159 PMCID: PMC10723307 DOI: 10.1101/2023.12.03.569812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
The spheroidal shape of the eye lens is critical for precise light focusing onto the retina. This shape is determined by concentrically aligned, convexly elongated lens fiber cells along the anterior and posterior axis of the lens. Upon differentiation at the lens equator, the fiber cells increase in height as their apical and basal tips migrate towards the anterior and posterior poles, respectively. The forces driving this elongation and migration remain unclear. We found that membrane protrusions or lamellipodia are observed only in the maturing fibers undergoing cell curve conversion, indicating lamellipodium is not the primary driver of earlier fiber migration. We demonstrated that elevated levels of fibroblast growth factor (FGF) suppressed the extension of Rac-dependent protrusions, suggesting changes in the activity of FGF controling Rac activity, switching to lamellipodium-driven migration. Inhibitors of ROCK, myosin, and actin reduced the height of both early and later fibers, indicating elongation of these fibers relies on actomyosin contractility. Consistently, active RhoA was detected throughout these fibers. Given that FGF promotes fiber elongation, we propose it to do so through regulation of Rho activity.
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Affiliation(s)
- Yuki Sugiyama
- Developmental Neurobiology Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa 904-0495, Japan
- Save Sight Institute, The University of Sydney, Sydney, NSW 2000, Australia
| | - Daniel A. Reed
- Cancer Ecosystems Program, The Garvan Institute of Medical Research & The Kinghorn Cancer Centre, St Vincent’s Clinical School, Faculty of Medicine, UNSW Sydney, Sydney, NSW 2010, Australia
| | - David Herrmann
- Cancer Ecosystems Program, The Garvan Institute of Medical Research & The Kinghorn Cancer Centre, St Vincent’s Clinical School, Faculty of Medicine, UNSW Sydney, Sydney, NSW 2010, Australia
| | - Frank J. Lovicu
- Save Sight Institute, The University of Sydney, Sydney, NSW 2000, Australia
- Molecular and Cellular Biomedicine, School of Medical Sciences, The University of Sydney, Sydney, NSW 2006, Australia
| | - Michael L. Robinson
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH, USA
| | - Paul Timpson
- Cancer Ecosystems Program, The Garvan Institute of Medical Research & The Kinghorn Cancer Centre, St Vincent’s Clinical School, Faculty of Medicine, UNSW Sydney, Sydney, NSW 2010, Australia
| | - Ichiro Masai
- Developmental Neurobiology Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa 904-0495, Japan
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3
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Wang Z, Gletten RB, Schey KL. Spatially Resolved Proteomics Reveals Lens Suture-Related Cell-Cell Junctional Protein Distributions. Invest Ophthalmol Vis Sci 2023; 64:28. [PMID: 37603353 PMCID: PMC10445239 DOI: 10.1167/iovs.64.11.28] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 07/31/2023] [Indexed: 08/22/2023] Open
Abstract
Purpose Lens transparency relies on the precise organization of lens fiber cells. The formation of the highly ordered lens architecture results from not only cell-cell adhesion along the lateral interfaces, but also from proper organization of fiber cells tips at lens sutures. Little is known about the cell adhesion between fiber tips at the sutures. The purpose of this study is to map suture-specific protein distributions. Methods Tissue sections were obtained from fresh frozen bovine lenses and washes were performed to remove soluble proteins and to retain membrane and membrane associated proteins. Imaging mass spectrometry (IMS) combined with on-tissue trypsin digestion was used to visualize protein spatial distributions. Sutures and adjacent regions were captured by laser capture microdissection and samples were digested by trypsin. Proteins were analyzed by liquid chromatography tandem MS and quantified by label-free quantification. Protein spatial distributions were confirmed by immunofluorescence. Results IMS results showed enrichment of adherens junction proteins cadherin-2 and armadillo repeat gene deleted in velo-cardio-facial syndrome (ARVCF) in both anterior and posterior sutures of bovine lenses. Liquid chromatography tandem MS confirmed higher expression of cadherin-2 and ARVCF and other adherens junction proteins including catenin α2 (CTNNA2) and catenin β1 (CTNNB1) in sutures. In contrast, IMS indicated low expression of gap junction protein connexin 50 and connexin 46 in the suture regions. The localization of cadherin-2 and connexin 50 was confirmed by immunofluorescence. Conclusions The complementary expression of adherens junction proteins and gap junction proteins in lens suture regions implicates adherens junctions in fiber cell tip adhesion and in maintaining the integrity of the lens.
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Affiliation(s)
- Zhen Wang
- Department of Biochemistry and Mass Spectrometry Research Center, Vanderbilt University School of Medicine, Nashville, Tennessee, United States
| | - Romell B. Gletten
- Department of Biochemistry and Mass Spectrometry Research Center, Vanderbilt University School of Medicine, Nashville, Tennessee, United States
| | - Kevin L. Schey
- Department of Biochemistry and Mass Spectrometry Research Center, Vanderbilt University School of Medicine, Nashville, Tennessee, United States
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4
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Islam ST, Cheng C, Parreno J, Fowler VM. Nonmuscle Myosin IIA Regulates the Precise Alignment of Hexagonal Eye Lens Epithelial Cells During Fiber Cell Formation and Differentiation. Invest Ophthalmol Vis Sci 2023; 64:20. [PMID: 37070941 PMCID: PMC10123325 DOI: 10.1167/iovs.64.4.20] [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: 10/21/2022] [Accepted: 03/27/2023] [Indexed: 04/19/2023] Open
Abstract
Purpose Epithelial cells in the equatorial region of the ocular lens undergo a remarkable transition from randomly packed cells into precisely aligned and hexagon-shaped cells organized into meridional rows. We investigated the function of nonmuscle myosin IIA (encoded by Myh9) in regulating equatorial epithelial cell alignment to form meridional rows during secondary fiber cell morphogenesis. Methods We used genetic knock-in mice to study a common human Myh9 mutation, E1841K, in the rod domain. The E1841K mutation disrupts bipolar filament assembly. Lens shape, clarity, and stiffness were evaluated, and Western blots were used to determine the level of normal and mutant myosins. Cryosections and lens whole mounts were stained and imaged by confocal microscopy to investigate cell shape and organization. Results We observed no obvious changes in lens size, shape, and biomechanical properties (stiffness and resilience) between the control and nonmuscle myosin IIA-E1841K mutant mice at 2 months of age. Surprisingly, we found misalignment and disorder of fiber cells in heterozygous and homozygous mutant lenses. Further analysis revealed misshapen equatorial epithelial cells that cause disorientation of the meridional rows before fiber cell differentiation in homozygous mutant lenses. Conclusions Our data indicate that nonmuscle myosin IIA bipolar filament assembly is required for the precise alignment of the meridional rows at the lens equator and that the organization of lens fiber cells depends on the proper patterning of meridional row epithelial cells. These data also suggest that lens fiber cell organization and a hexagonal shape are not required for normal lens size, shape transparency, or biomechanical properties.
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Affiliation(s)
- Sadia T. Islam
- Department of Biological Sciences, University of Delaware, Newark, Delaware, United States
| | - Catherine Cheng
- School of Optometry and Vision Science Program, Indiana University, Bloomington, Indiana, United States
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States
| | - Justin Parreno
- Department of Biological Sciences, University of Delaware, Newark, Delaware, United States
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States
| | - Velia M. Fowler
- Department of Biological Sciences, University of Delaware, Newark, Delaware, United States
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States
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Liu Z, Huang S, Zheng Y, Zhou T, Hu L, Xiong L, Li DWC, Liu Y. The lens epithelium as a major determinant in the development, maintenance, and regeneration of the crystalline lens. Prog Retin Eye Res 2023; 92:101112. [PMID: 36055924 DOI: 10.1016/j.preteyeres.2022.101112] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 07/28/2022] [Accepted: 08/02/2022] [Indexed: 02/01/2023]
Abstract
The crystalline lens is a transparent and refractive biconvex structure formed by lens epithelial cells (LECs) and lens fibers. Lens opacity, also known as cataracts, is the leading cause of blindness in the world. LECs are the principal cells of lens throughout human life, exhibiting different physiological properties and functions. During the embryonic stage, LECs proliferate and differentiate into lens fibers, which form the crystalline lens. Genetics and environment are vital factors that influence normal lens development. During maturation, LECs help maintain lens homeostasis through material transport, synthesis and metabolism as well as mitosis and proliferation. If disturbed, this will result in loss of lens transparency. After cataract surgery, the repair potential of LECs is activated and the structure and transparency of the regenerative tissue depends on postoperative microenvironment. This review summarizes recent research advances on the role of LECs in lens development, homeostasis, and regeneration, with a particular focus on the role of cholesterol synthesis (eg., lanosterol synthase) in lens development and homeostasis maintenance, and how the regenerative potential of LECs can be harnessed to develop surgical strategies and improve the outcomes of cataract surgery (Fig. 1). These new insights suggest that LECs are a major determinant of the physiological and pathological state of the lens. Further studies on their molecular biology will offer possibility to explore new approaches for cataract prevention and treatment.
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Affiliation(s)
- Zhenzhen Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, 510060, China
| | - Shan Huang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, 510060, China
| | - Yingfeng Zheng
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, 510060, China
| | - Tian Zhou
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, 510060, China
| | - Leyi Hu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, 510060, China
| | - Lang Xiong
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, 510060, China
| | - David Wan-Cheng Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, 510060, China
| | - Yizhi Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, 510060, China; Research Unit of Ocular Development and Regeneration, Chinese Academy of Medical Sciences, Beijing, 100085, China.
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6
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Xing H, Huang Y, Kunkemoeller BH, Dahl PJ, Muraleetharan O, Malvankar NS, Murrell MP, Kyriakides TR. Dysregulation of TSP2-Rac1-WAVE2 axis in diabetic cells leads to cytoskeletal disorganization, increased cell stiffness, and dysfunction. Sci Rep 2022; 12:22474. [PMID: 36577792 PMCID: PMC9797577 DOI: 10.1038/s41598-022-26337-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 12/13/2022] [Indexed: 12/29/2022] Open
Abstract
Fibroblasts are a major cell population that perform critical functions in the wound healing process. In response to injury, they proliferate and migrate into the wound space, engaging in extracellular matrix (ECM) production, remodeling, and contraction. However, there is limited knowledge of how fibroblast functions are altered in diabetes. To address this gap, several state-of-the-art microscopy techniques were employed to investigate morphology, migration, ECM production, 2D traction, 3D contraction, and cell stiffness. Analysis of cell-derived matrix (CDM) revealed that diabetic fibroblasts produce thickened and less porous ECM that hindered migration of normal fibroblasts. In addition, diabetic fibroblasts were found to lose spindle-like shape, migrate slower, generate less traction force, exert limited 3D contractility, and have increased cell stiffness. These changes were due, in part, to a decreased level of active Rac1 and a lack of co-localization between F-actin and Waskott-Aldrich syndrome protein family verprolin homologous protein 2 (WAVE2). Interestingly, deletion of thrombospondin-2 (TSP2) in diabetic fibroblasts rescued these phenotypes and restored normal levels of active Rac1 and WAVE2-F-actin co-localization. These results provide a comprehensive view of the extent of diabetic fibroblast dysfunction, highlighting the regulatory role of the TSP2-Rac1-WAVE2-actin axis, and describing a new function of TSP2 in regulating cytoskeleton organization.
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Affiliation(s)
- Hao Xing
- Department of Biomedical Engineering, Yale University, New Haven, USA.,Vascular Biology and Therapeutics Program, Yale University, New Haven, USA
| | - Yaqing Huang
- Department of Pathology, Yale University, New Haven, USA.,Vascular Biology and Therapeutics Program, Yale University, New Haven, USA
| | - Britta H Kunkemoeller
- Department of Pathology, Yale University, New Haven, USA.,Vascular Biology and Therapeutics Program, Yale University, New Haven, USA
| | - Peter J Dahl
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, USA.,Microbial Sciences Institute, Yale University, New Haven, USA
| | | | - Nikhil S Malvankar
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, USA.,Microbial Sciences Institute, Yale University, New Haven, USA
| | - Michael P Murrell
- Department of Biomedical Engineering, Yale University, New Haven, USA.,Department of Physics, Yale University, New Haven, USA.,Systems Biology Institute, Yale University, New Haven, USA
| | - Themis R Kyriakides
- Department of Biomedical Engineering, Yale University, New Haven, USA. .,Department of Pathology, Yale University, New Haven, USA. .,Vascular Biology and Therapeutics Program, Yale University, New Haven, USA.
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7
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Martin JB, Herman K, Houssin NS, Rich W, Reilly MA, Plageman TF. Arvcf Dependent Adherens Junction Stability is Required to Prevent Age-Related Cortical Cataracts. Front Cell Dev Biol 2022; 10:840129. [PMID: 35874813 PMCID: PMC9297370 DOI: 10.3389/fcell.2022.840129] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 06/14/2022] [Indexed: 11/30/2022] Open
Abstract
The etiology of age-related cortical cataracts is not well understood but is speculated to be related to alterations in cell adhesion and/or the changing mechanical stresses occurring in the lens with time. The role of cell adhesion in maintaining lens transparency with age is difficult to assess because of the developmental and physiological roles that well-characterized adhesion proteins have in the lens. This report demonstrates that Arvcf, a member of the p120-catenin subfamily of catenins that bind to the juxtamembrane domain of cadherins, is an essential fiber cell protein that preserves lens transparency with age in mice. No major developmental defects are observed in the absence of Arvcf, however, cortical cataracts emerge in all animals examined older than 6-months of age. While opacities are not obvious in young animals, histological anomalies are observed in lenses at 4-weeks that include fiber cell separations, regions of hexagonal lattice disorganization, and absence of immunolabeled membranes. Compression analysis of whole lenses also revealed that Arvcf is required for their normal biomechanical properties. Immunofluorescent labeling of control and Arvcf-deficient lens fiber cells revealed a reduction in membrane localization of N-cadherin, β-catenin, and αN-catenin. Furthermore, super-resolution imaging demonstrated that the reduction in protein membrane localization is correlated with smaller cadherin nanoclusters. Additional characterization of lens fiber cell morphology with electron microscopy and high resolution fluorescent imaging also showed that the cellular protrusions of fiber cells are abnormally elongated with a reduction and disorganization of cadherin complex protein localization. Together, these data demonstrate that Arvcf is required to maintain transparency with age by mediating the stability of the N-cadherin protein complex in adherens junctions.
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Affiliation(s)
- Jessica B. Martin
- College of Optometry, The Ohio State University, Columbus, OH, United States
| | - Kenneth Herman
- College of Optometry, The Ohio State University, Columbus, OH, United States
| | - Nathalie S. Houssin
- College of Optometry, The Ohio State University, Columbus, OH, United States
| | - Wade Rich
- Department of Biomedical Engineering, College of Engineering, The Ohio State University, Columbus, OH, United States
| | - Matthew A. Reilly
- Department of Biomedical Engineering, College of Engineering, The Ohio State University, Columbus, OH, United States
- Department of Ophthalmology and Visual Science, College of Medicine, The Ohio State University, Columbus, OH, United States
| | - Timothy F. Plageman
- College of Optometry, The Ohio State University, Columbus, OH, United States
- *Correspondence: Timothy F. Plageman Jr.,
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8
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Li Z, Quan Y, Gu S, Jiang JX. Beyond the Channels: Adhesion Functions of Aquaporin 0 and Connexin 50 in Lens Development. Front Cell Dev Biol 2022; 10:866980. [PMID: 35465319 PMCID: PMC9022433 DOI: 10.3389/fcell.2022.866980] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 03/18/2022] [Indexed: 12/04/2022] Open
Abstract
Lens, an avascular tissue involved in light transmission, generates an internal microcirculatory system to promote ion and fluid circulation, thus providing nutrients to internal lens cells and excreting the waste. This unique system makes up for the lack of vasculature and distinctively maintains lens homeostasis and lens fiber cell survival through channels of connexins and other transporters. Aquaporins (AQP) and connexins (Cx) comprise the majority of channels in the lens microcirculation system and are, thus, essential for lens development and transparency. Mutations of AQPs and Cxs result in abnormal channel function and cataract formation. Interestingly, in the last decade or so, increasing evidence has emerged suggesting that in addition to their well-established channel functions, AQP0 and Cx50 play pivotal roles through channel-independent actions in lens development and transparency. Specifically, AQP0 and Cx50 have been shown to have a unique cell adhesion function that mediates lens development and transparency. Precise regulation of cell-matrix and cell-cell adhesion is necessary for cell migration, a critical process during lens development. This review will provide recent advances in basic research of cell adhesion mediated by AQP0 and Cx50.
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Affiliation(s)
- Zhen Li
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center, San Antonio, TX, United States
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Yumeng Quan
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center, San Antonio, TX, United States
| | - Sumin Gu
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center, San Antonio, TX, United States
| | - Jean X. Jiang
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center, San Antonio, TX, United States
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9
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Baker MJ, Kazanietz MG. The anti-Rac1-GTP antibody and the detection of active Rac1: a tool with a fundamental flaw. Small GTPases 2022; 13:136-140. [PMID: 33910489 PMCID: PMC9707529 DOI: 10.1080/21541248.2021.1920824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Rac1 is a member of the Rho GTPase family and is involved in many cellular processes, particularly the formation of actin-rich membrane protrusions, such as lamellipodia and ruffles. With such a widely studied protein, it is essential that the research community has reliable tools for detecting Rac1 activation both in cellular models and tissues. Using a series of cancer cellular models, we recently demonstrated that a widely used antibody for visualizing active Rac1 (Rac1-GTP) does not recognize Rac1 but instead recognizes vimentin filaments (Baker MJ, J. Biol. Chem. 295:13698-13710, 2020). We believe that this tool has misled the field and impose on the GTPase research community the need to validate published results using this antibody as well as to continue the development of new resources to visualize endogenous active Rac1.
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Affiliation(s)
- Martin J. Baker
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Marcelo G. Kazanietz
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA,CONTACT Marcelo G. Kazanietz Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, 1256 Biomedical Research Building II/III, 421 Curie Blvd., Philadelphia, PA19104-6160, USA
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10
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Wu W, Lois N, Prescott AR, Brown AP, Van Gerwen V, Tassignon MJ, Richards SA, Saunter CD, Jarrin M, Quinlan RA. The importance of the epithelial fibre cell interface to lens regeneration in an in vivo rat model and in a human bag-in-the-lens (BiL) sample. Exp Eye Res 2021; 213:108808. [PMID: 34762932 DOI: 10.1016/j.exer.2021.108808] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 10/20/2021] [Accepted: 10/22/2021] [Indexed: 12/13/2022]
Abstract
Human lens regeneration and the Bag-in-the-Lens (BIL) surgical treatment for cataract both depend upon lens capsule closure for their success. Our studies suggest that the first three days after surgery are critical to their long-term outcomes. Using a rat model of lens regeneration, we evidenced lens epithelial cell (LEC) proliferation increased some 50 fold in the first day before rapidly declining to rates observed in the germinative zone of the contra-lateral, un-operated lens. Cell multi-layering at the lens equator occurred on days 1 and 2, but then reorganised into two discrete layers by day 3. E- and N-cadherin expression preceded cell polarity being re-established during the first week. Aquaporin 0 (AQP0) was first detected in the elongated cells at the lens equator at day 7. Cells at the capsulotomy site, however, behaved very differently expressing the epithelial mesenchymal transition (EMT) markers fibronectin and alpha-smooth muscle actin (SMA) from day 3 onwards. The physical interaction between the apical surfaces of the anterior and posterior LECs from day 3 after surgery preceded cell elongation. In the human BIL sample fibre cell formation was confirmed by both histological and proteome analyses, but the cellular response is less ordered and variable culminating in Soemmerring's ring (SR) formation and sometimes Elschnig's pearls. This we evidence for lenses from a single patient. No bow region or recognisable epithelial-fibre cell interface (EFI) was evident and consequently the fibre cells were disorganised. We conclude that lens cells require spatial and cellular cues to initiate, sustain and produce an optically functional tissue in addition to capsule integrity and the EFI.
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Affiliation(s)
- Weiju Wu
- Department of Biosciences, South Road, Durham University, Durham, DH1 3LE, England, UK
| | - Noemi Lois
- Wellcome-Wolfson Institute for Experimental Medicine, Queens University Belfast, 97 Lisburn Rd, Belfast, BT9 7BL, Northern Ireland, UK.
| | - Alan R Prescott
- Dundee Imaging Facility & Division of Cell Signalling and Immunology, School of Life Sciences, University of Dundee, Dundee, DD1 5EH, Scotland, UK
| | - Adrian P Brown
- Department of Biosciences, South Road, Durham University, Durham, DH1 3LE, England, UK
| | - Veerle Van Gerwen
- Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
| | - Marie-José Tassignon
- Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium; Department of Ophthalmology, Antwerp University Hospital, Edegem, Belgium
| | - Shane A Richards
- School of Natural Sciences, University of Tasmania, Hobart TAS, Australia
| | | | - Miguel Jarrin
- Department of Biosciences, South Road, Durham University, Durham, DH1 3LE, England, UK
| | - Roy A Quinlan
- Department of Biosciences, South Road, Durham University, Durham, DH1 3LE, England, UK.
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11
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Karnam S, Maddala R, Stiber JA, Rao PV. Drebrin, an actin-binding protein, is required for lens morphogenesis and growth. Dev Dyn 2021; 250:1600-1617. [PMID: 33896079 PMCID: PMC8542647 DOI: 10.1002/dvdy.353] [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: 01/06/2021] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND Lens morphogenesis, architecture, and clarity are known to be critically dependent on actin cytoskeleton organization and cell adhesive interactions. There is limited knowledge, however regarding the identity and role of key proteins regulating actin cytoskeletal organization in the lens. This study investigated the role of drebrin, a developmentally regulated actin-binding protein, in mouse lens development by generating and characterizing a conditional knockout (cKO) mouse model using the Cre-LoxP recombination approach. RESULTS Drebrin E, a splice variant of DBN1 is a predominant isoform expressed in the mouse lens and exhibits a maturation-dependent downregulation. Drebrin co-distributes with actin in both epithelium and fibers. Conditional deficiency (both haploinsufficiency and complete absence) of drebrin results in disrupted lens morphogenesis leading to cataract and microphthalmia. The drebrin cKO lens reveals a dramatic decrease in epithelial height and width, E-cadherin, and proliferation, and increased apoptotic cell death and expression of α-smooth muscle actin, together with severely impaired fiber cell organization, polarity, and cell-cell adhesion. CONCLUSIONS This study demonstrates the requirement of drebrin in lens development and growth, with drebrin deficiency leading to impaired lens morphogenesis and microphthalmia.
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Affiliation(s)
- Shruthi Karnam
- Department of Ophthalmology, Duke University School of Medicine, Durham, NC. USA
| | - Rupalatha Maddala
- Department of Ophthalmology, Duke University School of Medicine, Durham, NC. USA
| | - Jonathan A Stiber
- Department of Medicine, Duke University School of Medicine, Durham, NC. USA
| | - Ponugoti V Rao
- Department of Ophthalmology, Duke University School of Medicine, Durham, NC. USA
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC. USA
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12
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Immune responses to injury and their links to eye disease. Transl Res 2021; 236:52-71. [PMID: 34051364 PMCID: PMC8380715 DOI: 10.1016/j.trsl.2021.05.005] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 05/12/2021] [Accepted: 05/24/2021] [Indexed: 12/31/2022]
Abstract
The eye is regarded as an immune privileged site. Since the presence of a vasculature would impair vision, the vasculature of the eye is located outside of the central light path. As a result, many regions of the eye evolved mechanisms to deliver immune cells to sites of dysgenesis, injury, or in response to the many age-related pathologies. While the purpose of these immune responses is reparative or protective, cytokines released by immune cells compromise visual acuity by inducing inflammation and fibrosis. The response to traumatic or pathological injury is distinct in different regions of the eye. Age-related diseases impact both the anterior and posterior segment and lead to reduced quality of life and blindness. Here we focus attention on the role that inflammation and fibrosis play in the progression of age-related pathologies of the cornea and the lens as well as in glaucoma, the formation of epiretinal membranes, and in proliferative vitreoretinopathy.
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Key Words
- 2ryERM
- A T-helper cell that expresses high levels of IL-17 which can suppress T-regulatory cell function
- A cytokine expressed early during inflammation that attracts neutrophils
- A cytokine expressed early during inflammation that attracts neutrophils, sometimes referred to as monocyte chemoattractant protein-1 (MCP-1))
- A mouse model that lacks functional T and B cells and used to study the immune response
- A pigmented mouse strain used for research and known to mount a primarily Th1 response to infection
- A protein encoded by the ADGRE1 gene that, in mice, is expressed primarily on macrophages
- A strain of pigmented mice used in glaucoma research
- ACAID
- APCs
- ASC
- An albino mouse strain used for research and known to mount a primarily Th2 response to infection
- Antigen Presenting Cells, this class includes dendritic cells and monocytes
- BALB/c
- BM
- C57BL6
- CCL2
- CD45
- CNS
- CXCL1
- Central Nervous System
- Cluster of differentiation 45 antigen
- DAMPs
- DBA/2J
- EBM
- ECM
- EMT
- ERM
- Epithelial Basement Membrane
- F4/80
- FGF2
- HA =hyaluronic acid
- HSK
- HSP
- HSPGs
- HSV
- ICN
- IL-20
- IL6
- ILM
- IOP
- Inner (or internal) limiting membrane
- Interleukin 6
- Interleukin-20
- MAGP1
- MHC-II
- Major histocompatibility complex type II, a class of MHC proteins typically found only on APCs
- Microfibril-associated glycoprotein 1
- N-cad
- N-cadherin
- NEI
- NK
- National Eye Institute
- Natural killer T cells
- PCO
- PDGF
- PDR
- PVD
- PVR
- Platelet derived growth factor
- Posterior capsular opacification
- RGC
- RPE
- RRD
- Rag1-/-
- Retinal ganglion cells
- Retinal pigment epithelial cells
- SMAD
- Sons of Mothers Against Decapentaplegic, SMADs are a class of molecules that mediate TGF and bone morphogenetic protein signaling
- T-helper cell 1 response, proinflammatory adaptive response involving interferon gamma and associated with autoimmunity
- T-helper cell 2 response involving IgE and interleukins 4,5, and 13, also induces the anti-inflammatory interleukin 10 family cytokines
- T-regulatory cell
- TG
- TGF1
- TM
- TNF
- Th1
- Th17
- Th2
- Transforming growth factor 1
- Treg
- Tumor necrosis factor a cytokine produced during inflammation
- VEGF
- Vascular endothelial growth factor
- WHO
- World Health Organization
- anterior chamber immune deviation
- anterior subcapsular cataracts
- basement membrane
- damage-associated molecular patterns
- epiretinal membrane
- epiretinal membrane secondary to disease pathology
- epithelial-mesenchymal transition
- extracellular matrix
- fibroblast growth factor 2, also referred to as basic FGF
- heat shock protein
- heparan sulfate proteoglycans
- herpes simplex virus
- herpes stromal keratitis
- iERM
- idiopathic epiretinal membrane
- intraepithelial corneal nerves
- intraocular pressure
- mTOR
- mechanistic target of rapamycin, a protein kinase encoded by the MTOR genes that regulates a variety of signal transduction events including cell growth, autophagy and actin cytoskeleton
- posterior vitreous detachment
- proliferative diabetic retinopathy
- proliferative vitreoretinopathy
- rhegmatogenous (rupture, tear) retinal detachment
- trabecular meshwork
- trigeminal ganglion
- αSMA
- α−Smooth muscle actin, a class of actin expressed in mesenchymal cells
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13
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Ranaei Pirmardan E, Barakat A, Zhang Y, Naseri M, Hafezi-Moghadam A. Diabetic cataract in the Nile grass rat: A longitudinal phenotypic study of pathology formation. FASEB J 2021; 35:e21593. [PMID: 33991133 DOI: 10.1096/fj.202100353r] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 03/22/2021] [Accepted: 03/29/2021] [Indexed: 12/14/2022]
Abstract
Diabetes is a major risk factor for cataract, the leading cause of blindness worldwide. There is an unmet need for a realistic model of diabetic cataract for mechanistic and longitudinal studies, as existing models do not reflect key aspects of the complex human disease. Here, we introduce and characterize diabetic cataract in the Nile grass rat (NGR, Arvicanthis niloticus), an established model of metabolic syndrome and type 2 diabetes (T2D). We conducted a longitudinal study of cataract in over 88 NGRs in their non-diabetic, pre-diabetic, and diabetic stages of metabolism. Oral glucose tolerance test (OGTT) results distinguished the metabolic stages. Diverse cataract types were observed in the course of diabetes, including cortical, posterior subcapsular (PSC), and anterior subcapsular (ASC), all of which succeeded a characteristic dotted ring stage in all animals. The onset ages of diabetes and cataract were 44 ± 3 vs 29 ± 1 (P < .001) and 66 ± 5 vs 58 ± 6 (not significant) weeks in females and males, respectively. Histological analysis revealed fiber disorganization, vacuolar structures, and cellular proliferation and migration in cataractous lenses. The lens epithelial cells (LECs) in non-diabetic young NGRs expressed the stress marker GRP78, as did LECs and migrated cells in the lenses of diabetic animals. Elucidating mechanisms underlying LEC proliferation and migration will be clinically valuable in prevention and treatment of posterior capsule opacification, a dreaded complication of cataract surgery. Marked changes in N-cadherin expression emphasized a role for LEC integrity in cataractogenesis. Apoptotic cells were dispersed in the equatorial areas in early cataractogenesis. Our study reveals diverse cataract types that spontaneously develop in the diabetic NGR, and which uniquely mirror the cataract and its chronic course of development in individuals with diabetes. We provide mechanistic insights into early stages of diabetic cataract. These unique characteristics make NGR highly suited for mechanistic studies, especially in the context of metabolism, diabetes, and aging.
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Affiliation(s)
- Ehsan Ranaei Pirmardan
- Molecular Biomarkers Nano-Imaging Laboratory, Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Aliaa Barakat
- Molecular Biomarkers Nano-Imaging Laboratory, Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Yuanlin Zhang
- Molecular Biomarkers Nano-Imaging Laboratory, Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Marzieh Naseri
- Oncopathology Research Center, Iran University of Medical Sciences, Tehran, Iran.,Department of Molecular Medicine, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Ali Hafezi-Moghadam
- Molecular Biomarkers Nano-Imaging Laboratory, Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
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14
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Walker JL, Menko AS. Immune cells in lens injury repair and fibrosis. Exp Eye Res 2021; 209:108664. [PMID: 34126081 DOI: 10.1016/j.exer.2021.108664] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 05/26/2021] [Accepted: 05/28/2021] [Indexed: 12/18/2022]
Abstract
Immune cells, both tissue resident immune cells and those immune cells recruited in response to wounding or degenerative conditions, are essential to both the maintenance and restoration of homeostasis in most tissues. These cells are typically provided to tissues by their closely associated vasculatures. However, the lens, like many of the tissues in the eye, are considered immune privileged sites because they have no associated vasculature. Such absence of immune cells was thought to protect the lens from inflammatory responses that would bring with them the danger of causing vision impairing opacities. However, it has now been shown, as occurs in other immune privileged sites in the eye, that novel pathways exist by which immune cells come to associate with the lens to protect it, maintain its homeostasis, and function in its regenerative repair. Here we review the discoveries that have revealed there are both innate and adaptive immune system responses to lens, and that, like most other tissues, the lens harbors a population of resident immune cells, which are the sentinels of danger or injury to a tissue. While resident and recruited immune cells are essential elements of lens homeostasis and repair, they also become the agents of disease, particularly as progenitors of pro-fibrogenic myofibroblasts. There still remains much to learn about the function of lens-associated immune cells in protection, repair and disease, the knowledge of which will provide new tools for maintaining the core functions of the lens in the visual system.
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Affiliation(s)
- Janice L Walker
- Department of Pathology, Anatomy and Cell Biology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, 19107, USA; Department of Ophthalmology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, 19107, USA
| | - A Sue Menko
- Department of Pathology, Anatomy and Cell Biology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, 19107, USA; Department of Ophthalmology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, 19107, USA.
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15
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Liu T, Li J, Yu L, Sun HX, Li J, Dong G, Hu Y, Li Y, Shen Y, Wu J, Gu Y. Cross-species single-cell transcriptomic analysis reveals pre-gastrulation developmental differences among pigs, monkeys, and humans. Cell Discov 2021; 7:8. [PMID: 33531465 PMCID: PMC7854681 DOI: 10.1038/s41421-020-00238-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Accepted: 12/09/2020] [Indexed: 12/14/2022] Open
Abstract
Interspecies blastocyst complementation enables organ-specific enrichment of xenogeneic pluripotent stem cell (PSC) derivatives, which raises an intriguing possibility to generate functional human tissues/organs in an animal host. However, differences in embryo development between human and host species may constitute the barrier for efficient chimera formation. Here, to understand these differences we constructed a complete single-cell landscape of early embryonic development of pig, which is considered one of the best host species for human organ generation, and systematically compared its epiblast development with that of human and monkey. Our results identified a developmental coordinate of pluripotency spectrum among pigs, humans and monkeys, and revealed species-specific differences in: (1) pluripotency progression; (2) metabolic transition; (3) epigenetic and transcriptional regulations of pluripotency; (4) cell surface proteins; and (5) trophectoderm development. These differences may prevent proper recognition and communication between donor human cells and host pig embryos, resulting in low integration and survival of human cells. These results offer new insights into evolutionary conserved and divergent processes during mammalian development and may be helpful for developing effective strategies to overcome low human-pig chimerism, thereby enabling the generation of functional human organs in pigs in the future.
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Affiliation(s)
- Tianbin Liu
- BGI Education Center, University of Chinese Academy of Sciences, Shenzhen, Guangdong, 518083, China.,BGI-Shenzhen, Shenzhen, Guangdong, 518083, China.,Guangdong Provincial Key Laboratory of Genome Read and Write, BGI-Shenzhen, Shenzhen, Guangdong, 518120, China
| | - Jie Li
- BGI Education Center, University of Chinese Academy of Sciences, Shenzhen, Guangdong, 518083, China.,BGI-Shenzhen, Shenzhen, Guangdong, 518083, China
| | - Leqian Yu
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA.,Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Hai-Xi Sun
- BGI-Shenzhen, Shenzhen, Guangdong, 518083, China.,Guangdong Provincial Key Laboratory of Genome Read and Write, BGI-Shenzhen, Shenzhen, Guangdong, 518120, China
| | - Jing Li
- BGI Education Center, University of Chinese Academy of Sciences, Shenzhen, Guangdong, 518083, China.,BGI-Shenzhen, Shenzhen, Guangdong, 518083, China.,Guangdong Provincial Key Laboratory of Genome Read and Write, BGI-Shenzhen, Shenzhen, Guangdong, 518120, China
| | - Guoyi Dong
- BGI Education Center, University of Chinese Academy of Sciences, Shenzhen, Guangdong, 518083, China.,BGI-Shenzhen, Shenzhen, Guangdong, 518083, China.,Guangdong Provincial Key Laboratory of Genome Read and Write, BGI-Shenzhen, Shenzhen, Guangdong, 518120, China
| | - Yingying Hu
- BGI-Shenzhen, Shenzhen, Guangdong, 518083, China.,Guangdong Provincial Key Laboratory of Genome Read and Write, BGI-Shenzhen, Shenzhen, Guangdong, 518120, China
| | - Yong Li
- BGI Institute of Applied Agriculture, BGI-Shenzhen, Shenzhen, Guangdong, 518120, China
| | - Yue Shen
- BGI-Shenzhen, Shenzhen, Guangdong, 518083, China.,Guangdong Provincial Key Laboratory of Genome Read and Write, BGI-Shenzhen, Shenzhen, Guangdong, 518120, China
| | - Jun Wu
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA. .,Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA.
| | - Ying Gu
- BGI Education Center, University of Chinese Academy of Sciences, Shenzhen, Guangdong, 518083, China. .,BGI-Shenzhen, Shenzhen, Guangdong, 518083, China. .,Guangdong Provincial Key Laboratory of Genome Read and Write, BGI-Shenzhen, Shenzhen, Guangdong, 518120, China. .,Institute for Stem cell and Regeneration, Chinese Academy of Sciences, Beijing, 100101, China.
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16
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Karnam S, Skiba NP, Rao PV. Biochemical and biomechanical characteristics of dystrophin-deficient mdx 3cv mouse lens. Biochim Biophys Acta Mol Basis Dis 2021; 1867:165998. [PMID: 33127476 PMCID: PMC8323981 DOI: 10.1016/j.bbadis.2020.165998] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 10/17/2020] [Accepted: 10/23/2020] [Indexed: 12/11/2022]
Abstract
The molecular and cellular basis for cataract development in mice lacking dystrophin, a scaffolding protein that links the cytoskeleton to the extracellular matrix, is poorly understood. In this study, we characterized lenses derived from the dystrophin-deficient mdx3cv mouse model. Expression of Dp71, a predominant isoform of dystrophin in the lens, was induced during lens fiber cell differentiation. Dp71 was found to co-distribute with dystroglycan, connexin-50 and 46, aquaporin-0, and NrCAM as a large cluster at the center of long arms of the hexagonal fibers. Although mdx3cv mouse lenses exhibited dramatically reduced levels of Dp71, only older lenses revealed punctate nuclear opacities compared to littermate wild type (WT) lenses. The levels of dystroglycan, syntrophin, and dystrobrevin which comprise the dystrophin-associated protein complex (DAPC), and NrCAM, connexin-50, and aquaporin-0, were significantly lower in the lens membrane fraction of adult mdx3cv mice compared to WT mice. Additionally, decreases were observed in myosin light chain phosphorylation and lens stiffness together with a significant elevation in the levels of utrophin, a functional homolog of dystrophin in mdx3cv mouse lenses compared to WT lenses. The levels of perlecan and laminin (ligands of α-dystroglycan) remained normal in dystrophin-deficient lens fibers. Taken together, although mdx3cv mouse lenses exhibit only minor defects in lens clarity possibly due to a compensatory increase in utrophin, the noted disruptions of DAPC, stability, and organization of membrane integral proteins of fibers, and stiffness of mdx3cv lenses reveal the importance of dystrophin and DAPC in maintaining lens clarity and function.
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Affiliation(s)
- Shruthi Karnam
- Department of Ophthalmology, Duke University School of Medicine, Durham, NC, USA
| | - Nikolai P Skiba
- Department of Ophthalmology, Duke University School of Medicine, Durham, NC, USA
| | - Ponugoti V Rao
- Department of Ophthalmology, Duke University School of Medicine, Durham, NC, USA; Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC, USA.
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17
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Oscar A, Haykin V, Dimitrova V, Petkova I, Zdravkov Y, Kostova S, Veleva N, Mitev V, Elenkov C, Isaeva A. Protein kinase CK2 in TGFβ-induced lens epithelial-mesenchymal transition. BIOTECHNOL BIOTEC EQ 2021. [DOI: 10.1080/13102818.2021.2003720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/09/2022] Open
Affiliation(s)
- Alexander Oscar
- Clinic of Ophthalmology, University ‘Alexandrovska’ Hospital, Sofia, Bulgaria
- Department of Ophthalmology, Medical Faculty, Medical University of Sofia, Sofia, Bulgaria
| | - Vasil Haykin
- Clinic of Ophthalmology, University ‘Alexandrovska’ Hospital, Sofia, Bulgaria
- Department of Ophthalmology, Medical Faculty, Medical University of Sofia, Sofia, Bulgaria
| | - Violeta Dimitrova
- Department of Medical Chemistry and Biochemistry, Medical University of Sofia, Sofia, Bulgaria
| | - Iva Petkova
- Clinic of Ophthalmology, University ‘Alexandrovska’ Hospital, Sofia, Bulgaria
- Department of Ophthalmology, Medical Faculty, Medical University of Sofia, Sofia, Bulgaria
| | - Yani Zdravkov
- Clinic of Ophthalmology, University ‘Alexandrovska’ Hospital, Sofia, Bulgaria
- Department of Ophthalmology, Medical Faculty, Medical University of Sofia, Sofia, Bulgaria
| | - Stanislava Kostova
- Clinic of Ophthalmology, University ‘Alexandrovska’ Hospital, Sofia, Bulgaria
- Department of Ophthalmology, Medical Faculty, Medical University of Sofia, Sofia, Bulgaria
| | - Nevyana Veleva
- Clinic of Ophthalmology, University ‘Alexandrovska’ Hospital, Sofia, Bulgaria
- Department of Ophthalmology, Medical Faculty, Medical University of Sofia, Sofia, Bulgaria
| | - Vanyo Mitev
- Department of Medical Chemistry and Biochemistry, Medical University of Sofia, Sofia, Bulgaria
| | | | - Antonia Isaeva
- Department of Medical Chemistry and Biochemistry, Medical University of Sofia, Sofia, Bulgaria
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18
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Yang L, Gao T, Li W, Luo Y, Ullah S, Fang X, Cao Y, Pei R. Ni-Nitrilotriacetic Acid Affinity SELEX Method for Selection of DNA Aptamers Specific to the N-Cadherin Protein. ACS COMBINATORIAL SCIENCE 2020; 22:867-872. [PMID: 33146506 DOI: 10.1021/acscombsci.0c00165] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Nucleic acid aptamers are single-stranded oligonucleotides that may be evolved for affinity and specificity for their targets and can be easily produced, regenerated, and stabilized. In this study, we adapted Ni-NTA (nickle-charged nitrilotriacetic acid) affinity-chromatography in the development of single-stranded DNA aptamers against N-cadherin protein by systematic evolution of ligands by exponential enrichment (SELEX). After ten rounds of selection, two aptamers, designated NS13 and NC23, were selected, which showed low dissociation constants of 93 and 174 nM, respectively. The 5'-carboxyfluorescein-labeled NS13 was used for the sensitive detection of N-cadherin protein by the enzyme-linked oligonucleotide assay (ELONA) method.
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Affiliation(s)
- Luyan Yang
- CAS Key Laboratory of Nano-Bio Interface, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China
| | - Tian Gao
- CAS Key Laboratory of Nano-Bio Interface, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China
| | - Wenjing Li
- CAS Key Laboratory of Nano-Bio Interface, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China
| | - Yu Luo
- CAS Key Laboratory of Nano-Bio Interface, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China
| | - Salim Ullah
- CAS Key Laboratory of Nano-Bio Interface, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China
| | - Xiaona Fang
- CAS Key Laboratory of Nano-Bio Interface, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China
| | - Yanwei Cao
- CAS Key Laboratory of Nano-Bio Interface, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China
| | - Renjun Pei
- CAS Key Laboratory of Nano-Bio Interface, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China
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19
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Baker MJ, Cooke M, Kreider-Letterman G, Garcia-Mata R, Janmey PA, Kazanietz MG. Evaluation of active Rac1 levels in cancer cells: A case of misleading conclusions from immunofluorescence analysis. J Biol Chem 2020; 295:13698-13710. [PMID: 32817335 DOI: 10.1074/jbc.ra120.013919] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 07/23/2020] [Indexed: 12/16/2022] Open
Abstract
A large number of aggressive cancer cell lines display elevated levels of activated Rac1, a small GTPase widely implicated in cytoskeleton reorganization, cell motility, and metastatic dissemination. A commonly accepted methodological approach for detecting Rac1 activation in cancer cells involves the use of a conformation-sensitive antibody that detects the active (GTP-bound) Rac1 without interacting with the GDP-bound inactive form. This antibody has been extensively used in fixed cell immunofluorescence and immunohistochemistry. Taking advantage of prostate and pancreatic cancer cell models known to have high basal Rac1-GTP levels, here we have established that this antibody does not recognize Rac1 but rather detects the intermediate filament protein vimentin. Indeed, Rac1-null PC3 prostate cancer cells or cancer models with low levels of Rac1 activation still show a high signal with the anti-Rac1-GTP antibody, which is lost upon silencing of vimentin expression. Moreover, this antibody was unable to detect activated Rac1 in membrane ruffles induced by epidermal growth factor stimulation. These results have profound implications for the study of this key GTPase in cancer, particularly because a large number of cancer cell lines with characteristic mesenchymal features show simultaneous up-regulation of vimentin and high basal Rac1-GTP levels when measured biochemically. This misleading correlation can lead to assumptions about the validity of this antibody and inaccurate conclusions that may affect the development of appropriate therapeutic approaches for targeting the Rac1 pathway.
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Affiliation(s)
- Martin J Baker
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
| | - Mariana Cooke
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA; Department of Medicine, Einstein Medical Center Philadelphia, Philadelphia, Pennsylvania, USA
| | | | | | - Paul A Janmey
- Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Marcelo G Kazanietz
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
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20
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DeDreu J, Bowen CJ, Logan CM, Pal-Ghosh S, Parlanti P, Stepp MA, Menko AS. An immune response to the avascular lens following wounding of the cornea involves ciliary zonule fibrils. FASEB J 2020; 34:9316-9336. [PMID: 32452112 PMCID: PMC7384020 DOI: 10.1096/fj.202000289r] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 04/22/2020] [Accepted: 04/28/2020] [Indexed: 12/12/2022]
Abstract
The lens and central cornea are avascular. It was assumed that the adult lens had no source of immune cells and that the basement membrane capsule surrounding the lens was a barrier to immune cell migration. Yet, microfibril‐associated protein‐1 (MAGP1)‐rich ciliary zonules that originate from the vasculature‐rich ciliary body and extend along the surface of the lens capsule, form a potential conduit for immune cells to the lens. In response to cornea debridement wounding, we find increased expression of MAGP1 throughout the central corneal stroma. The immune cells that populate this typically avascular region after wounding closely associate with this MAGP1‐rich matrix. These results suggest that MAGP1‐rich microfibrils support immune cell migration post‐injury. Using this cornea wound model, we investigated whether there is an immune response to the lens following cornea injury involving the lens‐associated MAGP1‐rich ciliary zonules. Our results provide the first evidence that following corneal wounding immune cells are activated to travel along zonule fibers that extend anteriorly along the equatorial surface of the lens, from where they migrate across the anterior lens capsule. These results demonstrate that lens‐associated ciliary zonules are directly involved in the lens immune response and suggest the ciliary body as a source of immune cells to the avascular lens.
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Affiliation(s)
- JodiRae DeDreu
- Department of Pathology, Anatomy and Cell Biology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
| | - Caitlin J Bowen
- Department of Pathology, Anatomy and Cell Biology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
| | - Caitlin M Logan
- Department of Pathology, Anatomy and Cell Biology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
| | - Sonali Pal-Ghosh
- Department of Anatomy and Cell Biology, George Washington University School of Medicine and Health Sciences, Washington, DC, USA
| | - Paola Parlanti
- George Washington University Nanofabrication and Imaging Center, George Washington University School of Medicine and Health Sciences, Washington, DC, USA
| | - Mary Ann Stepp
- Department of Anatomy and Cell Biology, George Washington University School of Medicine and Health Sciences, Washington, DC, USA.,Department of Ophthalmology, George Washington University School of Medicine and Health Sciences, Washington, DC, USA
| | - A Sue Menko
- Department of Pathology, Anatomy and Cell Biology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA.,Department of Ophthalmology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
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21
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Accogli A, Calabretta S, St-Onge J, Boudrahem-Addour N, Dionne-Laporte A, Joset P, Azzarello-Burri S, Rauch A, Krier J, Fieg E, Pallais JC, McConkie-Rosell A, McDonald M, Freedman SF, Rivière JB, Lafond-Lapalme J, Simpson BN, Hopkin RJ, Trimouille A, Van-Gils J, Begtrup A, McWalter K, Delphine H, Keren B, Genevieve D, Argilli E, Sherr EH, Severino M, Rouleau GA, Yam PT, Charron F, Srour M. De Novo Pathogenic Variants in N-cadherin Cause a Syndromic Neurodevelopmental Disorder with Corpus Collosum, Axon, Cardiac, Ocular, and Genital Defects. Am J Hum Genet 2019; 105:854-868. [PMID: 31585109 DOI: 10.1016/j.ajhg.2019.09.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 09/05/2019] [Indexed: 01/06/2023] Open
Abstract
Cadherins constitute a family of transmembrane proteins that mediate calcium-dependent cell-cell adhesion. The extracellular domain of cadherins consists of extracellular cadherin (EC) domains, separated by calcium binding sites. The EC interacts with other cadherin molecules in cis and in trans to mechanically hold apposing cell surfaces together. CDH2 encodes N-cadherin, whose essential roles in neural development include neuronal migration and axon pathfinding. However, CDH2 has not yet been linked to a Mendelian neurodevelopmental disorder. Here, we report de novo heterozygous pathogenic variants (seven missense, two frameshift) in CDH2 in nine individuals with a syndromic neurodevelopmental disorder characterized by global developmental delay and/or intellectual disability, variable axon pathfinding defects (corpus callosum agenesis or hypoplasia, mirror movements, Duane anomaly), and ocular, cardiac, and genital anomalies. All seven missense variants (c.1057G>A [p.Asp353Asn]; c.1789G>A [p.Asp597Asn]; c.1789G>T [p.Asp597Tyr]; c.1802A>C [p.Asn601Thr]; c.1839C>G [p.Cys613Trp]; c.1880A>G [p.Asp627Gly]; c.2027A>G [p.Tyr676Cys]) result in substitution of highly conserved residues, and six of seven cluster within EC domains 4 and 5. Four of the substitutions affect the calcium-binding site in the EC4-EC5 interdomain. We show that cells expressing these variants in the EC4-EC5 domains have a defect in cell-cell adhesion; this defect includes impaired binding in trans with N-cadherin-WT expressed on apposing cells. The two frameshift variants (c.2563_2564delCT [p.Leu855Valfs∗4]; c.2564_2567dupTGTT [p.Leu856Phefs∗5]) are predicted to lead to a truncated cytoplasmic domain. Our study demonstrates that de novo heterozygous variants in CDH2 impair the adhesive activity of N-cadherin, resulting in a multisystemic developmental disorder, that could be named ACOG syndrome (agenesis of corpus callosum, axon pathfinding, cardiac, ocular, and genital defects).
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Affiliation(s)
- Andrea Accogli
- Department of Pediatrics, Division of Pediatric Neurology, McGill University, H4A 3J1, Montreal, QC, Canada; Medical Genetics Unit, IRCCS Ospedale Policlinico San Martino, 16132 Genova, Italy; Dipartimento di Neuroscienze, Reabilitazione, Oftalmologia, Genetica e Scienze Materno-Infantili, Università degli Studi di Genova, 16132 Genova Italy
| | - Sara Calabretta
- Montreal Clinical Research Institute, H2W 1R7 Montreal, QC, Canada
| | - Judith St-Onge
- McGill University Health Center Research Institute, H4A 3J1, Montreal, QC, Canada
| | | | | | - Pascal Joset
- Institute of Medical Genetics, University of Zurich, CH-8952 Schlieren, Switzerland
| | | | - Anita Rauch
- Institute of Medical Genetics, University of Zurich, CH-8952 Schlieren, Switzerland
| | - Joel Krier
- Brigham and Women's Hospital, Boston, MA 02115, USA
| | | | | | - Allyn McConkie-Rosell
- Division of Medical Genetics, Department of Pediatrics, Duke University, Durham, NC 27707, USA
| | - Marie McDonald
- Division of Medical Genetics, Department of Pediatrics, Duke University, Durham, NC 27707, USA
| | - Sharon F Freedman
- Department of Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA
| | | | - Joël Lafond-Lapalme
- McGill University Health Center Research Institute, H4A 3J1, Montreal, QC, Canada
| | - Brittany N Simpson
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA
| | - Robert J Hopkin
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA
| | - Aurélien Trimouille
- Centre Hospitalier Universitaire Bordeaux, Service de Génétique Médicale, 33076 Bordeaux, France; Laboratoire Maladies Rares: Génétique et Métabolisme, Inserm U1211, Université de Bordeaux, 33076 Bordeaux, France
| | - Julien Van-Gils
- Centre Hospitalier Universitaire Bordeaux, Service de Génétique Médicale, 33076 Bordeaux, France; Laboratoire Maladies Rares: Génétique et Métabolisme, Inserm U1211, Université de Bordeaux, 33076 Bordeaux, France
| | | | | | - Heron Delphine
- Département de Génétique, Centre de Référence des Déficiences Intellectuelles de Causes Rares, Groupe Hospitalier Pitié-Salpêtrière, Assistance Publique-Hôpitaux de Paris, 75013 Paris
| | - Boris Keren
- Département de Génétique, Centre de Référence des Déficiences Intellectuelles de Causes Rares, Groupe Hospitalier Pitié-Salpêtrière, Assistance Publique-Hôpitaux de Paris, 75013 Paris
| | - David Genevieve
- Département de Genetique Médicale, Maladies Rares et Médecine Personnalisée, Centre de Référence Anomalies du Développement, Université Montpellier, Unité Inserm U1183, Centre Hospitalier Universitaire Montpellier, 34000 Montpellier, France
| | - Emanuela Argilli
- Departments of Neurology and Pediatrics, Weill Institute of Neuroscience and Institute of Human Genetics, University of California, CA 94143 San Francisco
| | - Elliott H Sherr
- Departments of Neurology and Pediatrics, Weill Institute of Neuroscience and Institute of Human Genetics, University of California, CA 94143 San Francisco
| | - Mariasavina Severino
- Istituto di Ricovero e Cura a Carattere Scientifico, Istituto Giannina Gaslini, 16147 Genova, Italy
| | - Guy A Rouleau
- Montreal Neurological Institute, McGill University, H3A 2B4, Montreal, QC, Canada; Department of Neurology and Neurosurgery, McGill University, H3A 2B4, Montreal, QC, Canada
| | - Patricia T Yam
- Montreal Clinical Research Institute, H2W 1R7 Montreal, QC, Canada
| | - Frédéric Charron
- Montreal Clinical Research Institute, H2W 1R7 Montreal, QC, Canada; Department of Medicine, University of Montreal, H3C 3J7, Montreal, QC, Canada; Department of Anatomy and Cell Biology, McGill University, H4A 3J1, Montreal, QC, Canada; Department of Experimental Medicine, McGill University, H4A 3J1, Montreal, QC, Canada.
| | - Myriam Srour
- Department of Pediatrics, Division of Pediatric Neurology, McGill University, H4A 3J1, Montreal, QC, Canada; McGill University Health Center Research Institute, H4A 3J1, Montreal, QC, Canada; Department of Neurology and Neurosurgery, McGill University, H3A 2B4, Montreal, QC, Canada.
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22
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Logan CM, Menko AS. Microtubules: Evolving roles and critical cellular interactions. Exp Biol Med (Maywood) 2019; 244:1240-1254. [PMID: 31387376 DOI: 10.1177/1535370219867296] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Microtubules are cytoskeletal elements known as drivers of directed cell migration, vesicle and organelle trafficking, and mitosis. In this review, we discuss new research in the lens that has shed light into further roles for stable microtubules in the process of development and morphogenesis. In the lens, as well as other systems, distinct roles for characteristically dynamic microtubules and stabilized populations are coming to light. Understanding the mechanisms of microtubule stabilization and the associated microtubule post-translational modifications is an evolving field of study. Appropriate cellular homeostasis relies on not only one cytoskeletal element, but also rather an interaction between cytoskeletal proteins as well as other cellular regulators. Microtubules are key integrators with actin and intermediate filaments, as well as cell–cell junctional proteins and other cellular regulators including myosin and RhoGTPases to maintain this balance.Impact statementThe role of microtubules in cellular functioning is constantly expanding. In this review, we examine new and exciting fields of discovery for microtubule’s involvement in morphogenesis, highlight our evolving understanding of differential roles for stabilized versus dynamic subpopulations, and further understanding of microtubules as a cellular integrator.
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Affiliation(s)
- Caitlin M Logan
- Pathology Anatomy and Cell Biology Department, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - A Sue Menko
- Pathology Anatomy and Cell Biology Department, Thomas Jefferson University, Philadelphia, PA 19107, USA
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Kumari S, Taginik G, Varadaraj S, Varadaraj K. Positively charged amino acid residues in the extracellular loops A and C of lens aquaporin 0 interact with the negative charges in the plasma membrane to facilitate cell-to-cell adhesion. Exp Eye Res 2019; 185:107682. [PMID: 31150637 DOI: 10.1016/j.exer.2019.05.022] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2018] [Revised: 04/17/2019] [Accepted: 05/27/2019] [Indexed: 01/12/2023]
Abstract
This investigation was undertaken to find out whether the positive charges in the Extracellular Loops A (ELA) and C (ELC) of Aquaporin 0 (AQP0) are involved in lens fiber cell-to-cell adhesion (CTCA), and the possible mechanism of CTCA. AQP0 ELA or ELC was substituted with the corresponding AQP1 loop via Polymerase Chain Reaction. Positively charged arginine (R) and histidine (H) of mouse AQP0 ELA and ELC were substituted individually with glutamine (Q) to create R33Q, H40Q, R113Q and H122Q by mutagenesis. cRNA expression, immunostaining, Förster Resonance Energy Transfer (FRET) studies and protein analyses showed localization of all mutants except AQP0-AQP1ELC chimera (AQP0 ELC substituted with AQP1 ELC) at the plasma membrane. Osmotic Swelling Assay revealed comparable water permeability (Pf) among AQP0-AQP1ELA, R33Q, R113Q, and WT. CTCA assay demonstrated a significant reduction in adhesion in all mutants compared to the WT (14-73%) suggesting the importance of the conserved positively charged residues of ELA and ELC for adhesion. Studies involving AQP0-transfected L-cells, and lipid vesicles indicated that CTCA was due to the electrostatic interaction between the positively charged amino acids of AQP0 extracellular loops and the negative charges of the plasma membrane. Schematic models are provided to illustrate the mechanism.
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Affiliation(s)
- Sindhu Kumari
- Department of Physiology and Biophysics, Stony Brook University, Stony Brook, NY, 11794-8661, USA
| | - Gozde Taginik
- Department of Physiology and Biophysics, Stony Brook University, Stony Brook, NY, 11794-8661, USA
| | - Sangeeth Varadaraj
- Department of Physiology and Biophysics, Stony Brook University, Stony Brook, NY, 11794-8661, USA
| | - Kulandaiappan Varadaraj
- Department of Physiology and Biophysics, Stony Brook University, Stony Brook, NY, 11794-8661, USA; SUNY Eye Institute, New York, NY, USA.
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24
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Menko AS, Walker JL, Stepp MA. Fibrosis: Shared Lessons From the Lens and Cornea. Anat Rec (Hoboken) 2019; 303:1689-1702. [PMID: 30768772 PMCID: PMC6697240 DOI: 10.1002/ar.24088] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Revised: 08/23/2018] [Accepted: 09/04/2018] [Indexed: 12/13/2022]
Abstract
Regenerative repair in response to wounding involves cell proliferation and migration. This is followed by the reestablishment of cell structure and organization and a dynamic process of remodeling and restoration of the injured cells' extracellular matrix microenvironment and the integration of the newly synthesized matrix into the surrounding tissue. Fibrosis in the lungs, liver, and heart can lead to loss of life and in the eye to loss of vision. Learning to control fibrosis and restore normal tissue function after injury repair remains a goal of research in this area. Here we use knowledge gained using the lens and the cornea to provide insight into how fibrosis develops and clues to how it can be controlled. The lens and cornea are less complex than other tissues that develop life‐threatening fibrosis, but they are well characterized and research using them as model systems to study fibrosis is leading toward an improved understanding of fibrosis. Here we summarize the current state of the literature and how it is leading to promising new treatments. Anat Rec, 2019. © 2019 The Authors. The Anatomical Record published by Wiley Periodicals, Inc. on behalf of American Association of Anatomists.
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Affiliation(s)
- A Sue Menko
- Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Janice L Walker
- Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Mary Ann Stepp
- Department of Anatomy and Cell Biology, George Washington University, Washington, District of Columbia
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25
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Ankyrin-G regulated epithelial phenotype is required for mouse lens morphogenesis and growth. Dev Biol 2018; 446:119-131. [PMID: 30562487 DOI: 10.1016/j.ydbio.2018.12.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 12/13/2018] [Accepted: 12/14/2018] [Indexed: 11/24/2022]
Abstract
Epithelial cell polarity, adhesion, proliferation, differentiation and survival are essential for morphogenesis of various organs and tissues including the ocular lens. The molecular mechanisms regulating the lens epithelial phenotype however, are not well understood. Here we investigated the role of scaffolding protein ankyrin-G (AnkG) in mouse lens development by conditional suppression of AnkG expression using the Cre-LoxP recombination approach. AnkG, which serves to link integral membrane proteins to the spectrin/actin cytoskeleton, was found to distribute predominantly to the lateral membranes of lens epithelium with several isoforms of the protein being detected in the mouse lens. Conditional deficiency of AnkG impaired mouse lens morphogenesis starting from embryonic stage E15.5, with neonatal (P1) AnkG cKO lenses exhibiting overt abnormalities in shape, size, epithelial cell height, sheet length and lateral membrane assembly together with defective fiber cell orientation relative to lenses from littermate AnkG floxed or Cre expressing mice. Severe disruptions in E-cadherin/β-catenin-based adherens junctions, and the membrane organization of spectrin-actin cytoskeleton, ZO-1, connexin-50 and Na+-K+-ATPase were noted in AnkG deficient lenses, along with detection in lens epithelium of α-smooth muscle actin, a marker of epithelial to mesenchymal transition. Moreover, lens epithelial cell proliferation and survival were severely compromised while differentiation appears to be normal in AnkG deficient mouse lenses. Collectively, these results indicate that AnkG regulates establishment of the epithelial phenotype via lateral membrane assembly, stabilization of E-cadherin-based cell-cell junctions, polarity and membrane organization of transport and adhesion proteins and the spectrin-actin skeleton, and provide evidence for an obligatory role for AnkG in lens morphogenesis and growth.
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26
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Varadaraj K, Kumari SS. Molecular mechanism of Aquaporin 0-induced fiber cell to fiber cell adhesion in the eye lens. Biochem Biophys Res Commun 2018; 506:284-289. [PMID: 30348525 DOI: 10.1016/j.bbrc.2018.10.066] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Accepted: 10/10/2018] [Indexed: 01/16/2023]
Abstract
Cell-to-cell adhesion (CTCA), which is key for establishing lens transparency, is a critical function of Aquaporin 0 (AQP0). The aim of this investigation was to find out the possible mechanism by which AQP0 exerts CTCA between fiber cells, since there are two proposals currently, either an AQP0-AQP0 interaction or an AQP0-lipid interaction. We studied the mechanism of AQP0-induced CTCA in intact AQP0 and C-terminally cleaved AQP0 (CTC-AQP0). Assays showed CTCA between L-cells transfected with intact AQP0 or CTC-AQP0 and parental L-cells indicating AQP0-membrane interaction. Both forms of AQP0 significantly (P < 0.001) promoted adhesion to negatively charged l-α-phosphatidylserine lipid vesicles signifying AQP0-lipid interaction. AQP0-expressing L-cells also promoted adhesion of WT and AQP0-KO mouse lens fiber cell membrane vesicles (FCMVs) significantly (P < 0.001). However, when FCMVs of WT or AQP0-KO were plated over parental L-cells, only WT vesicles adhered significantly, corroborating AQP0-membrane interaction. After incubating with extracellular domain-specific AQP0 antibody, L-cells expressing intact AQP0 or CTC-AQP0 showed a significant reduction (P < 0.001) in the adhesion of AQP0-KO FCMVs indicating extracellular loop involvement in CTCA. WT FCMVs from outer cortex and inner cortex promoted adhesion to parental L-cells, without any statistically significant difference in adhesion efficiency (P > 0.05). Ultrastructure studies of WT, AQP0-KO and transgenic lenses showed AQP0 is critical for fiber CTCA and compaction. The data collected clearly demonstrate that the positively charged amino acids in the AQP0 extracellular loop domains interact with the negatively charged lipids in the plasma membrane to promote CTCA for compaction of fiber cells.
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Affiliation(s)
- Kulandaiappan Varadaraj
- Department of Physiology and Biophysics, Stony Brook University, Stony Brook, NY, USA; SUNY Eye Institute, New York, NY, USA.
| | - S Sindhu Kumari
- Department of Physiology and Biophysics, Stony Brook University, Stony Brook, NY, USA
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27
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Vite A, Zhang C, Yi R, Emms S, Radice GL. α-Catenin-dependent cytoskeletal tension controls Yap activity in the heart. Development 2018; 145:dev.149823. [PMID: 29467248 PMCID: PMC5868989 DOI: 10.1242/dev.149823] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 02/07/2018] [Indexed: 01/08/2023]
Abstract
Shortly after birth, muscle cells of the mammalian heart lose their ability to divide. At the same time, the N-cadherin/catenin cell adhesion complex accumulates at the cell termini, creating a specialized type of cell-cell contact called the intercalated disc (ICD). To investigate the relationship between ICD maturation and proliferation, αE-catenin (Ctnna1) and αT-catenin (Ctnna3) genes were deleted to generate cardiac-specific α-catenin double knockout (DKO) mice. DKO mice exhibited aberrant N-cadherin expression, mislocalized actomyosin activity and increased cardiomyocyte proliferation that was dependent on Yap activity. To assess effects on tension, cardiomyocytes were cultured on deformable polyacrylamide hydrogels of varying stiffness. When grown on a stiff substrate, DKO cardiomyocytes exhibited increased cell spreading, nuclear Yap and proliferation. A low dose of either a myosin or RhoA inhibitor was sufficient to block Yap accumulation in the nucleus. Finally, activation of RhoA was sufficient to increase nuclear Yap in wild-type cardiomyocytes. These data demonstrate that α-catenins regulate ICD maturation and actomyosin contractility, which, in turn, control Yap subcellular localization, thus providing an explanation for the loss of proliferative capacity in the newborn mammalian heart.
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Affiliation(s)
- Alexia Vite
- Center for Translational Medicine, Department of Medicine, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Caimei Zhang
- Center for Translational Medicine, Department of Medicine, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Roslyn Yi
- Center for Translational Medicine, Department of Medicine, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Sabrina Emms
- Center for Translational Medicine, Department of Medicine, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Glenn L Radice
- Center for Translational Medicine, Department of Medicine, Thomas Jefferson University, Philadelphia, PA 19107, USA
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28
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Collins TN, Mao Y, Li H, Bouaziz M, Hong A, Feng GS, Wang F, Quilliam LA, Chen L, Park T, Curran T, Zhang X. Crk proteins transduce FGF signaling to promote lens fiber cell elongation. eLife 2018; 7:32586. [PMID: 29360039 PMCID: PMC5818251 DOI: 10.7554/elife.32586] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2017] [Accepted: 01/23/2018] [Indexed: 12/17/2022] Open
Abstract
Specific cell shapes are fundamental to the organization and function of multicellular organisms. Fibroblast Growth Factor (FGF) signaling induces the elongation of lens fiber cells during vertebrate lens development. Nonetheless, exactly how this extracellular FGF signal is transmitted to the cytoskeletal network has previously not been determined. Here, we show that the Crk family of adaptor proteins, Crk and Crkl, are required for mouse lens morphogenesis but not differentiation. Genetic ablation and epistasis experiments demonstrated that Crk and Crkl play overlapping roles downstream of FGF signaling in order to regulate lens fiber cell elongation. Upon FGF stimulation, Crk proteins were found to interact with Frs2, Shp2 and Grb2. The loss of Crk proteins was partially compensated for by the activation of Ras and Rac signaling. These results reveal that Crk proteins are important partners of the Frs2/Shp2/Grb2 complex in mediating FGF signaling, specifically promoting cell shape changes. As an embryo develops, its cells divide multiple times to transform into the specialized cell types that form our tissues and organs. To carry out specific roles, cells need to be of a certain shape. For example, in mammals, the cells that make up the main portion of the eye lens, develop into a fiber-like shape to be perfectly aligned with each other. This enables them to transmit light to the retina at the rear end of the eye. To do so, the lens cells increase over 1000 times in length with the help of a group of proteins called the Fibroblast Growth Factor, or FGF for short. The FGF pathway includes a network of interacting proteins that transmit signals to molecules inside the lens cells to control how they specialize and grow. However, until now it was not clear how it does this. Here, Zhang et al. used mouse lens-cells grown in the laboratory to investigate how FGF signaling causes cells to change their structure. The experiments revealed two related proteins called Crk and Crkl that linked the FGF pathway with another signaling system. When these two proteins were removed from the lens cells, the lens cells were still able to specialize, but could no longer grow in length. This suggests that these two processes are independent of each other. Moreover, Crk and Crkl helped the cells to change shape by increasing the amount of another group of proteins called Ras, which are known to both help cells to specialize and to regulate their shape. Zhang et al. discovered that the amount of Ras proteins determined whether cells specialized or modified their shape by changing the organization of proteins in the cell. Millions of children are born with cataracts, a disease caused when lens cells fail to shape properly. A better knowledge of FGF signaling may help to understand how cataracts develop and inspire future treatments. Moreover, the pathways identified in this study could also apply to other organs and diseases in which FGF signaling is active.
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Affiliation(s)
- Tamica N Collins
- Departments of Ophthalmology, Pathology and Cell Biology, Columbia University, New York, United States
| | - Yingyu Mao
- Departments of Ophthalmology, Pathology and Cell Biology, Columbia University, New York, United States
| | - Hongge Li
- Departments of Ophthalmology, Pathology and Cell Biology, Columbia University, New York, United States
| | - Michael Bouaziz
- Departments of Ophthalmology, Pathology and Cell Biology, Columbia University, New York, United States
| | - Angela Hong
- Departments of Ophthalmology, Pathology and Cell Biology, Columbia University, New York, United States
| | - Gen-Sheng Feng
- Department of Pathology, University of California San Diego, La Jolla, United States
| | - Fen Wang
- Center for Cancer Biology and Nutrition, Houston, United States
| | - Lawrence A Quilliam
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, United States
| | - Lin Chen
- Department of Rehabilitation Medicine, Third Military Medical University, Chongqing, China
| | - Taeju Park
- The Children's Research Institute, Children's Mercy Kansas City, Kansas City, United States
| | - Tom Curran
- The Children's Research Institute, Children's Mercy Kansas City, Kansas City, United States
| | - Xin Zhang
- Departments of Ophthalmology, Pathology and Cell Biology, Columbia University, New York, United States
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Petpiroon N, Sritularak B, Chanvorachote P. Phoyunnanin E inhibits migration of non-small cell lung cancer cells via suppression of epithelial-to-mesenchymal transition and integrin αv and integrin β3. BMC COMPLEMENTARY AND ALTERNATIVE MEDICINE 2017; 17:553. [PMID: 29284478 PMCID: PMC5747023 DOI: 10.1186/s12906-017-2059-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Accepted: 12/12/2017] [Indexed: 01/17/2023]
Abstract
BACKGROUND The conversion of the epithelial phenotype of cancer cells into cells with a mesenchymal phenotype-so-called epithelial-mesenchymal transition (EMT)-has been shown to enhance the capacity of the cells to disseminate throughout the body. EMT is therefore becoming a potential target for anti-cancer drug discovery. Here, we showed that phoyunnanin E, a compound isolated from Dendrobium venustum, possesses anti-migration activity and addressed its mechanism of action. METHODS The cytotoxic and proliferative effects of phoyunnanin E on human non-small cell lung cancer-derived H460, H292, and A549 cells and human keratinocyte HaCaT cells were investigated by MTT assay. The effect of phoyunnanin E on EMT was evaluated by determining the colony formation and EMT markers. The migration and invasion of H460, H292, A549 and HaCaT cells was evaluated by wound healing assay and transwell invasion assay, respectively. EMT markers, integrins and migration-associated proteins were examined by western blot analysis. RESULTS Phoyunnanin E at the concentrations of 5 and 10 μM, which are non-toxic to H460, H292, A549 and HaCaT cells showed good potential to inhibit the migratory activity of three types of human lung cancer cells. The anti-migration effect of phoyunnanin E was shown to relate to the suppressed EMT phenotypes, including growth in anchorage-independent condition, cell motility, and EMT-specific protein markers (N-cadherin, vimentin, slug, and snail). In addition to EMT suppression, we found that phoyunnanin E treatment with 5 and 10 μM could decrease the cellular level of integrin αv and integrin β3, these integrins are frequently up-regulated in highly metastatic tumor cells. We further characterized the regulatory proteins in cell migration and found that the cells treated with phoyunnanin E exhibited a significantly lower level of phosphorylated focal adhesion kinase (p-FAK) and phosphorylated ATP-dependent tyrosine kinase (p-AKT), and their downstream effectors (including Ras-related C3 botulinum (Rac-GTP); Cell division cycle 42 (Cdc42); and Ras homolog gene family, member A (Rho-GTP)) in comparison to those of the non-treated control. CONCLUSIONS We have determined for the first time that phoyunnanin E could inhibit the motility of lung cancer cells via the suppression of EMT and metastasis-related integrins. This new information could support further development of this compound for anti-metastasis approaches.
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30
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Logan CM, Bowen CJ, Menko AS. Functional role for stable microtubules in lens fiber cell elongation. Exp Cell Res 2017; 362:477-488. [PMID: 29253534 DOI: 10.1016/j.yexcr.2017.12.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 11/17/2017] [Accepted: 12/13/2017] [Indexed: 02/06/2023]
Abstract
The process of tissue morphogenesis, especially for tissues reliant on the establishment of a specific cytoarchitecture for their functionality, depends a balanced interplay between cytoskeletal elements and their interactions with cell adhesion molecules. The microtubule cytoskeleton, which has many roles in the cell, is a determinant of directional cell migration, a process that underlies many aspects of development. We investigated the role of microtubules in development of the lens, a tissue where cell elongation underlies morphogenesis. Our studies with the microtubule depolymerizing agent nocodazole revealed an essential function for the acetylated population of stable microtubules in the elongation of lens fiber cells, which was linked to their regulation of the activation state of myosin. Suppressing myosin activation with the inhibitor blebbistatin could attenuate the loss of acetylated microtubules by nocodazole and rescue the effect of this microtubule depolymerization agent on both fiber cell elongation and lens integrity. Our results also suggest that acetylated microtubules impact lens morphogenesis through their interaction with N-cadherin junctions, with which they specifically associate in the region where lens fiber cell elongate. Disruption of the stable microtubule network increased N-cadherin junctional organization along lateral borders of differentiating lens fiber cells, which was prevented by suppression of myosin activity. These results reveal a role for the stable microtubule population in lens fiber cell elongation, acting in tandem with N-cadherin cell-cell junctions and the actomyosin network, giving insight into the cooperative role these systems play in tissue morphogenesis.
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Affiliation(s)
- Caitlin M Logan
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107, United States.
| | - Caitlin J Bowen
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107, United States.
| | - A Sue Menko
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107, United States.
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Logan CM, Bowen CJ, Menko AS. Induction of Immune Surveillance of the Dysmorphogenic Lens. Sci Rep 2017; 7:16235. [PMID: 29176738 PMCID: PMC5701161 DOI: 10.1038/s41598-017-16456-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 11/12/2017] [Indexed: 01/10/2023] Open
Abstract
The lens has been considered to be an immune privileged site not susceptible to the immune processes normally associated with tissue injury and wound repair. However, as greater insight into the immune surveillance process is gained, we have reevaluated the concept of immune privilege. Our studies using an N-cadherin lens-specific conditional knockout mouse, N-cadΔlens, show that loss of this cell-cell junctional protein leads to lens degeneration, necrosis and fibrotic change, postnatally. The degeneration of this tissue induces an immune response resulting in immune cells populating the lens that contribute to the development of fibrosis. Additionally, we demonstrate that the lens is connected to the lymphatic system, with LYVE(+) labeling reaching the lens along the suspensory ligaments that connect the lens to the ciliary body, providing a potential mechanism for the immune circulation. Importantly, we observe that degeneration of the lens activates an immune response throughout the eye, including cornea, vitreous humor, and retina, suggesting a coordinated protective response in the visual system to defects of a component tissue. These studies demonstrate that lens degeneration induces an immune response that can contribute to the fibrosis that often accompanies lens dysgenesis, a consideration for understanding organ system response to injury.
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Affiliation(s)
- Caitlin M Logan
- Thomas Jefferson University, Department of Pathology, Anatomy and Cell Biology, Philadelphia, Pennsylvania, 19107, United States
| | - Caitlin J Bowen
- Thomas Jefferson University, Department of Pathology, Anatomy and Cell Biology, Philadelphia, Pennsylvania, 19107, United States
| | - A Sue Menko
- Thomas Jefferson University, Department of Pathology, Anatomy and Cell Biology, Philadelphia, Pennsylvania, 19107, United States.
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