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Upreti A, Padula SL, Weaver JM, Wagner BD, Kneller AM, Petulla AL, Lachke SA, Robinson ML. A Transcriptomics Analysis of the Regulation of Lens Fiber Cell Differentiation in the Absence of FGFRs and PTEN. Cells 2024; 13:1222. [PMID: 39056803 PMCID: PMC11274593 DOI: 10.3390/cells13141222] [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: 04/24/2024] [Revised: 06/28/2024] [Accepted: 07/17/2024] [Indexed: 07/28/2024] Open
Abstract
Adding 50% vitreous humor to the media surrounding lens explants induces fiber cell differentiation and a significant immune/inflammatory response. While Fgfr loss blocks differentiation in lens epithelial explants, this blockage is partially reversed by deleting Pten. To investigate the functions of the Fgfrs and Pten during lens fiber cell differentiation, we utilized a lens epithelial explant system and conducted RNA sequencing on vitreous humor-exposed explants lacking Fgfrs, or Pten or both Fgfrs and Pten. We found that Fgfr loss impairs both vitreous-induced differentiation and inflammation while the additional loss of Pten restores these responses. Furthermore, transcriptomic analysis suggested that PDGFR-signaling in FGFR-deficient explants is required to mediate the rescue of vitreous-induced fiber differentiation in explants lacking both Fgfrs and Pten. The blockage of β-crystallin induction in explants lacking both Fgfrs and Pten in the presence of a PDGFR inhibitor supports this hypothesis. Our findings demonstrate that a wide array of genes associated with fiber cell differentiation are downstream of FGFR-signaling and that the vitreous-induced immune responses also depend on FGFR-signaling. Our data also demonstrate that many of the vitreous-induced gene-expression changes in Fgfr-deficient explants are rescued in explants lacking both Fgfrs and Pten.
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Affiliation(s)
- Anil Upreti
- Cell, Molecular and Structural Biology Program, Miami University, Oxford, OH 45056, USA; (A.U.); (S.L.P.); (J.M.W.)
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH 45056, USA; (B.D.W.); (A.M.K.); (A.L.P.)
| | - Stephanie L. Padula
- Cell, Molecular and Structural Biology Program, Miami University, Oxford, OH 45056, USA; (A.U.); (S.L.P.); (J.M.W.)
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH 45056, USA; (B.D.W.); (A.M.K.); (A.L.P.)
| | - Jacob M. Weaver
- Cell, Molecular and Structural Biology Program, Miami University, Oxford, OH 45056, USA; (A.U.); (S.L.P.); (J.M.W.)
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH 45056, USA; (B.D.W.); (A.M.K.); (A.L.P.)
| | - Brad D. Wagner
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH 45056, USA; (B.D.W.); (A.M.K.); (A.L.P.)
| | - Allison M. Kneller
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH 45056, USA; (B.D.W.); (A.M.K.); (A.L.P.)
| | - Anthony L. Petulla
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH 45056, USA; (B.D.W.); (A.M.K.); (A.L.P.)
| | - Salil A. Lachke
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA;
- Center for Bioinformatics and Computational Biology, University of Delaware, Newark, DE 19716, USA
| | - Michael L. Robinson
- Cell, Molecular and Structural Biology Program, Miami University, Oxford, OH 45056, USA; (A.U.); (S.L.P.); (J.M.W.)
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH 45056, USA; (B.D.W.); (A.M.K.); (A.L.P.)
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2
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VanSlyke JK, Boswell BA, Musil LS. TGFβ overcomes FGF-induced transinhibition of EGFR in lens cells to enable fibrotic secondary cataract. Mol Biol Cell 2024; 35:ar75. [PMID: 38598298 PMCID: PMC11238076 DOI: 10.1091/mbc.e24-01-0040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Revised: 03/29/2024] [Accepted: 04/04/2024] [Indexed: 04/12/2024] Open
Abstract
To cause vision-disrupting fibrotic secondary cataract (PCO), lens epithelial cells that survive cataract surgery must migrate to the posterior of the lens capsule and differentiate into myofibroblasts. During this process, the cells become exposed to the FGF that diffuses out of the vitreous body. In normal development, such relatively high levels of FGF induce lens epithelial cells to differentiate into lens fiber cells. It has been a mystery as to how lens cells could instead undergo a mutually exclusive cell fate, namely epithelial to myofibroblast transition, in the FGF-rich environment of the posterior capsule. We and others have reported that the ability of TGFβ to induce lens cell fibrosis requires the activity of endogenous ErbBs. We show here that lens fiber-promoting levels of FGF induce desensitization of ErbB1 (EGFR) that involves its phosphorylation on threonine 669 mediated by both ERK and p38 activity. Transinhibition of ErbB1 by FGF is overcome by a time-dependent increase in ErbB1 levels induced by TGFβ, the activation of which is increased after cataract surgery. Our studies provide a rationale for why TGFβ upregulates ErbB1 in lens cells and further support the receptor as a therapeutic target for PCO.
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Affiliation(s)
- Judy K. VanSlyke
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR 97239
| | - Bruce A. Boswell
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR 97239
| | - Linda S. Musil
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR 97239
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3
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VanSlyke JK, Boswell BA, Musil LS. Tonic ErbB signaling underlies TGFβ-induced activation of ERK and is required for lens cell epithelial to myofibroblast transition. Mol Biol Cell 2024; 35:ar35. [PMID: 38170570 PMCID: PMC10916858 DOI: 10.1091/mbc.e23-07-0294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 11/01/2023] [Accepted: 12/20/2023] [Indexed: 01/05/2024] Open
Abstract
Fibrosis is a major, but incompletely understood, component of many diseases. The most common vision-disrupting complication of cataract surgery involves differentiation of residual lens cells into myofibroblasts. In serum-free primary cultures of lens epithelial cells (DCDMLs), inhibitors of either ERK or of ErbB signaling prevent TGFβ from upregulating both early (fibronectin) and late (αSMA) markers of myofibroblast differentiation. TGFβ stimulates ERK in DCDMLs within 1.5 h. Kinase inhibitors of ErbBs, but not of several other growth factor receptors in lens cells, reduce phospho ERK to below basal levels in the absence or presence of TGFβ. This effect is attributable to constitutive ErbB activity playing a major role in regulating the basal levels pERK. Additional studies support a model in which TGFβ-generated reactive oxygen species serve to indirectly amplify ERK signaling downstream of tonically active ErbBs to mediate myofibroblast differentiation. ERK activity is in turn essential for expression of ErbB1 and ErbB2, major inducers of ERK signaling. By mechanistically linking TGFβ, ErbB, and ERK signaling to myofibroblast differentiation, our data elucidate a new role for ErbBs in fibrosis and reveal a novel mode by which TGFβ directs lens cell fate.
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Affiliation(s)
- Judy K. VanSlyke
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, Oregon 97239
| | - Bruce A. Boswell
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, Oregon 97239
| | - Linda S. Musil
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, Oregon 97239
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4
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Hsu J, Francis JH, Ahmad S. Ocular toxicities of fibroblast growth factor receptor inhibitors: A review. Surv Ophthalmol 2024; 69:34-41. [PMID: 37777119 DOI: 10.1016/j.survophthal.2023.09.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2023] [Revised: 09/24/2023] [Accepted: 09/25/2023] [Indexed: 10/02/2023]
Abstract
Fibroblast growth factor receptor (FGFR) inhibitors are an emerging class of small molecule targeted cancer drugs with promising therapeutic possibilities for a wide variety of malignancies. While ocular adverse events from FGFR inhibitors are reported in clinical trials, subsequent case studies continue to reveal new toxicities. Disease pathology affecting multiple parts of the eye has been reported, but the ocular surface and the retina are the most commonly encountered areas affected by FGFR inhibitors, manifesting as dry eye and FGFR inhibitor-associated retinopathy, respectively. Corneal thinning and melt is a rare but serious and potentially vision-threatening complication of FGFR inhibitor toxicity. Similarities between toxicities observed from other targeted cancer therapy drugs and FGFR inhibitors may help us understand underlying pathophysiological changes. The management of these adverse events requires close ophthalmologic follow-up and may require discontinuation of the offending agents in some cases.
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Affiliation(s)
- Jerry Hsu
- New York Eye and Ear Infirmary of Mount Sinai, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Jasmine H Francis
- Ophthalmic Oncology Service, Memorial Sloan Kettering Cancer Center, New York, NY, USA; Department of Ophthalmology, Weill-Cornell Medical Center, New York, NY, USA
| | - Sumayya Ahmad
- New York Eye and Ear Infirmary of Mount Sinai, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
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Tangeman JA, Rebull SM, Grajales-Esquivel E, Weaver JM, Bendezu-Sayas S, Robinson ML, Lachke SA, Del Rio-Tsonis K. Integrated single-cell multiomics uncovers foundational regulatory mechanisms of lens development and pathology. Development 2024; 151:dev202249. [PMID: 38180241 PMCID: PMC10906490 DOI: 10.1242/dev.202249] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Accepted: 11/28/2023] [Indexed: 01/06/2024]
Abstract
Ocular lens development entails epithelial to fiber cell differentiation, defects in which cause congenital cataracts. We report the first single-cell multiomic atlas of lens development, leveraging snRNA-seq, snATAC-seq and CUT&RUN-seq to discover previously unreported mechanisms of cell fate determination and cataract-linked regulatory networks. A comprehensive profile of cis- and trans-regulatory interactions, including for the cataract-linked transcription factor MAF, is established across a temporal trajectory of fiber cell differentiation. Furthermore, we identify an epigenetic paradigm of cellular differentiation, defined by progressive loss of the H3K27 methylation writer Polycomb repressive complex 2 (PRC2). PRC2 localizes to heterochromatin domains across master-regulator transcription factor gene bodies, suggesting it safeguards epithelial cell fate. Moreover, we demonstrate that FGF hyper-stimulation in vivo leads to MAF network activation and the emergence of novel lens cell states. Collectively, these data depict a comprehensive portrait of lens fiber cell differentiation, while defining regulatory effectors of cell identity and cataract formation.
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Affiliation(s)
- Jared A. Tangeman
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH 45056, USA
- Cell, Molecular, and Structural Biology Program, Miami University, Oxford, OH 45056, USA
| | - Sofia M. Rebull
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH 45056, USA
| | - Erika Grajales-Esquivel
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH 45056, USA
| | - Jacob M. Weaver
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH 45056, USA
- Cell, Molecular, and Structural Biology Program, Miami University, Oxford, OH 45056, USA
| | - Stacy Bendezu-Sayas
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH 45056, USA
- Cell, Molecular, and Structural Biology Program, Miami University, Oxford, OH 45056, USA
| | - Michael L. Robinson
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH 45056, USA
- Cell, Molecular, and Structural Biology Program, Miami University, Oxford, OH 45056, USA
| | - Salil A. Lachke
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
- Center for Bioinformatics & Computational Biology, University of Delaware, Newark, DE 19713, USA
| | - Katia Del Rio-Tsonis
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH 45056, USA
- Cell, Molecular, and Structural Biology Program, Miami University, Oxford, OH 45056, USA
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6
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Sun Q, Li J, Ma J, Zheng Y, Ju R, Li X, Ren X, Huang L, Chen R, Tan X, Luo L. JAM-C Is Important for Lens Epithelial Cell Proliferation and Lens Fiber Maturation in Murine Lens Development. Invest Ophthalmol Vis Sci 2023; 64:15. [PMID: 38095908 PMCID: PMC10723223 DOI: 10.1167/iovs.64.15.15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2023] [Accepted: 11/16/2023] [Indexed: 12/17/2023] Open
Abstract
Purpose The underlying mechanism of congenital cataracts caused by deficiency or mutation of junctional adhesion molecule C (JAM-C) gene remains unclear. Our study aims to elucidate the abnormal developmental process in Jamc-/- lenses and reveal the genes related to lens development that JAM-C may regulate. Methods Jamc knockout (Jamc-/-) mouse embryos and pups were generated for in vivo studies. Four key developmental stages from embryonic day (E) 12.5 to postnatal day (P) 0.5 were selected for the following experiments. Hematoxylin and eosin staining was used for histological analysis. The 5-bromo-2'-deoxyuridine (BrdU) incorporation assay and TUNEL staining were performed to label lens epithelial cell (LEC) proliferation and apoptosis, respectively. Immunofluorescence and Western blot were used to analyze the markers of lens epithelium, cell cycle exit, and lens fiber differentiation. Results JAM-C was expressed throughout the process of lens development. Deletion of Jamc resulted in decreased lens size and disorganized lens fibers, which arose from E16.5 and aggravated gradually. The LECs of Jamc-/- lenses showed decreased quantity and proliferation, accompanied with reduction of key transcription factor, FOXE3. The fibers in Jamc-/- lenses were disorganized. Moreover, Jamc-deficient lens fibers showed significantly altered distribution patterns of Cx46 and Cx50. The marker of fiber homeostasis, γ-crystallin, was also decreased in the inner cortex and core fibers of Jamc-/- lenses. Conclusions Deletion of JAM-C exhibits malfunction of LEC proliferation and fiber maturation during murine lens development, which may be related to the downregulation of FOXE3 expression and abnormal localization patterns of Cx46 and Cx50.
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Affiliation(s)
- Qihang Sun
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Jiani Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Jingyu Ma
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Yuxing Zheng
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Rong Ju
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Xuri Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Xiangrong Ren
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Lijuan Huang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Rongyuan Chen
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Xuhua Tan
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Lixia Luo
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
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7
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Geervliet E, Terstappen LWMM, Bansal R. Hepatocyte survival and proliferation by fibroblast growth factor 7 attenuates liver inflammation, and fibrogenesis during acute liver injury via paracrine mechanisms. Biomed Pharmacother 2023; 167:115612. [PMID: 37797460 DOI: 10.1016/j.biopha.2023.115612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 09/18/2023] [Accepted: 09/27/2023] [Indexed: 10/07/2023] Open
Abstract
Hepatocyte damage during liver injury instigates activation of macrophages and hepatic stellate cells (HSCs) resulting in liver inflammation and fibrosis respectively. Improving hepatocyte survival and proliferation thereby ameliorating inflammation and fibrosis represents a promising approach for the treatment of liver injury. In the liver, fibroblast growth factors (FGFs) play a crucial role in promoting hepatocyte proliferation and tissue regeneration. Among 22 FGFs, FGF7 induces hepatocyte survival and liver regeneration as shown previously in mouse models of cholestatic liver injury and partial hepatectomy. We hypothesized that FGF7 promotes hepatocyte survival and proliferation by interacting with FGFR2b, expressed on hepatocytes, and ameliorates liver injury (inflammation and early fibrogenesis) via paracrine mechanisms. To prove this hypothesis and to study the effect of FGF7 on hepatocytes and liver injury, we administered FGF7 exogenously to mice with acute carbon tetrachloride (CCl4)-induced liver injury. We thereafter studied the underlying mechanisms and the effect of exogenous FGF7 on hepatocyte survival and proliferation, and the consequent paracrine effects on macrophage-induced inflammation, and HSCs activation in vitro and in vivo. We observed that the expression of FGF7 as well as FGFR2 is upregulated during acute liver injury. Co-immunostaining of FGF7 and collagen-I confirmed that FGF7 is expressed by HSCs and is possibly captured by the secreted ECM. Immunohistochemical analysis of liver sections showed increased hepatocyte proliferation upon exogenous FGF7 treatment as determined by Ki67 expression. Mechanistically, exogenous FGF7 improved hepatocyte survival (and increased drug detoxification) via AKT and ERK pathways while maintaining hepatocyte quiescence restricting hepatocarcinogenesis via P27 pathways. Flow cytometry analysis revealed that improved hepatocyte survival and proliferation leads to a decrease in infiltrated monocytes-derived macrophages, as a result of reduced CCL2 (and CXCL8) expression by hepatocytes. Moreover, conditioned medium studies showed reduced collagen-I secretion by HSCs (indicative of HSCs activation) upon treatment with FGF7-treated hepatocytes conditioned medium. Altogether, we show that exogenous administration of FGF7 induces hepatocyte survival and proliferation and leads to amelioration of inflammatory response and fibrosis in acute liver injury via paracrine mechanisms. Our study further demonstrates that FGF7, FGF7 derivatives, or nano-engineered FGF7 may benefit patients with hepatic dysfunction.
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Affiliation(s)
- Eline Geervliet
- Translational Liver Research, Department of Medical Cell BioPhysics, Technical Medical Centre, Faculty of Science and Technology, University of Twente, the Netherlands; Institute of Molecular Pathobiochemistry, Experimental Gene Therapy and Clinical Chemistry, RWTH University Hospital Aachen, Germany
| | - Leon W M M Terstappen
- Department of Medical Cell BioPhysics, Technical Medical Centre, Faculty of Science and Technology, University of Twente, the Netherlands
| | - Ruchi Bansal
- Translational Liver Research, Department of Medical Cell BioPhysics, Technical Medical Centre, Faculty of Science and Technology, University of Twente, the Netherlands.
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8
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Tangeman JA, Rebull SM, Grajales-Esquivel E, Weaver JM, Bendezu-Sayas S, Robinson ML, Lachke SA, Rio-Tsonis KD. Integrated single-cell multiomics uncovers foundational regulatory mechanisms of lens development and pathology. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.10.548451. [PMID: 37502967 PMCID: PMC10369908 DOI: 10.1101/2023.07.10.548451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Ocular lens development entails epithelial to fiber cell differentiation, defects in which cause congenital cataract. We report the first single-cell multiomic atlas of lens development, leveraging snRNA-seq, snATAC-seq, and CUT&RUN-seq to discover novel mechanisms of cell fate determination and cataract-linked regulatory networks. A comprehensive profile of cis- and trans-regulatory interactions, including for the cataract-linked transcription factor MAF, is established across a temporal trajectory of fiber cell differentiation. Further, we divulge a conserved epigenetic paradigm of cellular differentiation, defined by progressive loss of H3K27 methylation writer Polycomb repressive complex 2 (PRC2). PRC2 localizes to heterochromatin domains across master-regulator transcription factor gene bodies, suggesting it safeguards epithelial cell fate. Moreover, we demonstrate that FGF hyper-stimulation in vivo leads to MAF network activation and the emergence of novel lens cell states. Collectively, these data depict a comprehensive portrait of lens fiber cell differentiation, while defining regulatory effectors of cell identity and cataract formation.
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Affiliation(s)
- Jared A Tangeman
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH 45056 USA
- Cell, Molecular, and Structural Biology Program, Miami University, Oxford, OH 45056 USA
| | - Sofia M Rebull
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH 45056 USA
| | - Erika Grajales-Esquivel
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH 45056 USA
| | - Jacob M Weaver
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH 45056 USA
- Cell, Molecular, and Structural Biology Program, Miami University, Oxford, OH 45056 USA
| | - Stacy Bendezu-Sayas
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH 45056 USA
- Cell, Molecular, and Structural Biology Program, Miami University, Oxford, OH 45056 USA
| | - Michael L Robinson
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH 45056 USA
- Cell, Molecular, and Structural Biology Program, Miami University, Oxford, OH 45056 USA
| | - Salil A Lachke
- Department of Biological Sciences, University of Delaware, Newark, DE 19716 USA
- Center for Bioinformatics & Computational Biology, University of Delaware, Newark, DE 19713 USA
| | - Katia Del Rio-Tsonis
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH 45056 USA
- Cell, Molecular, and Structural Biology Program, Miami University, Oxford, OH 45056 USA
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9
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Daruich A, Duncan M, Robert MP, Lagali N, Semina EV, Aberdam D, Ferrari S, Romano V, des Roziers CB, Benkortebi R, De Vergnes N, Polak M, Chiambaretta F, Nischal KK, Behar-Cohen F, Valleix S, Bremond-Gignac D. Congenital aniridia beyond black eyes: From phenotype and novel genetic mechanisms to innovative therapeutic approaches. Prog Retin Eye Res 2023; 95:101133. [PMID: 36280537 PMCID: PMC11062406 DOI: 10.1016/j.preteyeres.2022.101133] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2022] [Revised: 09/27/2022] [Accepted: 10/03/2022] [Indexed: 11/05/2022]
Abstract
Congenital PAX6-aniridia, initially characterized by the absence of the iris, has progressively been shown to be associated with other developmental ocular abnormalities and systemic features making congenital aniridia a complex syndromic disorder rather than a simple isolated disease of the iris. Moreover, foveal hypoplasia is now recognized as a more frequent feature than complete iris hypoplasia and a major visual prognosis determinant, reversing the classical clinical picture of this disease. Conversely, iris malformation is also a feature of various anterior segment dysgenesis disorders caused by PAX6-related developmental genes, adding a level of genetic complexity for accurate molecular diagnosis of aniridia. Therefore, the clinical recognition and differential genetic diagnosis of PAX6-related aniridia has been revealed to be much more challenging than initially thought, and still remains under-investigated. Here, we update specific clinical features of aniridia, with emphasis on their genotype correlations, as well as provide new knowledge regarding the PAX6 gene and its mutational spectrum, and highlight the beneficial utility of clinically implementing targeted Next-Generation Sequencing combined with Whole-Genome Sequencing to increase the genetic diagnostic yield of aniridia. We also present new molecular mechanisms underlying aniridia and aniridia-like phenotypes. Finally, we discuss the appropriate medical and surgical management of aniridic eyes, as well as innovative therapeutic options. Altogether, these combined clinical-genetic approaches will help to accelerate time to diagnosis, provide better determination of the disease prognosis and management, and confirm eligibility for future clinical trials or genetic-specific therapies.
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Affiliation(s)
- Alejandra Daruich
- Ophthalmology Department, Necker-Enfants Malades University Hospital, AP-HP, Paris Cité University, Paris, France; INSERM, UMRS1138, Team 17, From Physiopathology of Ocular Diseases to Clinical Development, Sorbonne Paris Cité University, Centre de Recherche des Cordeliers, Paris, France
| | - Melinda Duncan
- Department of Biological Sciences, University of Delaware, Newark, DE, USA
| | - Matthieu P Robert
- Ophthalmology Department, Necker-Enfants Malades University Hospital, AP-HP, Paris Cité University, Paris, France; Borelli Centre, UMR 9010, CNRS-SSA-ENS Paris Saclay-Paris Cité University, Paris, France
| | - Neil Lagali
- Division of Ophthalmology, Department of Biomedical and Clinical Sciences, Faculty of Medicine, Linköping University, 581 83, Linköping, Sweden; Department of Ophthalmology, Sørlandet Hospital Arendal, Arendal, Norway
| | - Elena V Semina
- Department of Pediatrics, Children's Research Institute at the Medical College of Wisconsin and Children's Hospital of Wisconsin, Milwaukee, WI, 53226, USA
| | - Daniel Aberdam
- INSERM, UMRS1138, Team 17, From Physiopathology of Ocular Diseases to Clinical Development, Sorbonne Paris Cité University, Centre de Recherche des Cordeliers, Paris, France
| | - Stefano Ferrari
- Fondazione Banca degli Occhi del Veneto, Via Paccagnella 11, Venice, Italy
| | - Vito Romano
- Department of Medical and Surgical Specialties, Radiolological Sciences, and Public Health, Ophthalmology Clinic, University of Brescia, Italy
| | - Cyril Burin des Roziers
- INSERM, UMRS1138, Team 17, From Physiopathology of Ocular Diseases to Clinical Development, Sorbonne Paris Cité University, Centre de Recherche des Cordeliers, Paris, France; Service de Médecine Génomique des Maladies de Système et d'Organe, APHP. Centre Université de Paris, Fédération de Génétique et de Médecine Génomique Hôpital Cochin, 27 rue du Fbg St-Jacques, 75679, Paris Cedex 14, France
| | - Rabia Benkortebi
- Ophthalmology Department, Necker-Enfants Malades University Hospital, AP-HP, Paris Cité University, Paris, France
| | - Nathalie De Vergnes
- Ophthalmology Department, Necker-Enfants Malades University Hospital, AP-HP, Paris Cité University, Paris, France
| | - Michel Polak
- Pediatric Endocrinology, Gynecology and Diabetology, Hôpital Universitaire Necker Enfants Malades, AP-HP, Paris Cité University, INSERM U1016, Institut IMAGINE, France
| | | | - Ken K Nischal
- Division of Pediatric Ophthalmology, Strabismus, and Adult Motility, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA, USA; UPMC Eye Center, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - Francine Behar-Cohen
- INSERM, UMRS1138, Team 17, From Physiopathology of Ocular Diseases to Clinical Development, Sorbonne Paris Cité University, Centre de Recherche des Cordeliers, Paris, France
| | - Sophie Valleix
- INSERM, UMRS1138, Team 17, From Physiopathology of Ocular Diseases to Clinical Development, Sorbonne Paris Cité University, Centre de Recherche des Cordeliers, Paris, France; Service de Médecine Génomique des Maladies de Système et d'Organe, APHP. Centre Université de Paris, Fédération de Génétique et de Médecine Génomique Hôpital Cochin, 27 rue du Fbg St-Jacques, 75679, Paris Cedex 14, France
| | - Dominique Bremond-Gignac
- Ophthalmology Department, Necker-Enfants Malades University Hospital, AP-HP, Paris Cité University, Paris, France; INSERM, UMRS1138, Team 17, From Physiopathology of Ocular Diseases to Clinical Development, Sorbonne Paris Cité University, Centre de Recherche des Cordeliers, Paris, France.
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10
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Shah R, Amador C, Chun ST, Ghiam S, Saghizadeh M, Kramerov AA, Ljubimov AV. Non-canonical Wnt signaling in the eye. Prog Retin Eye Res 2023; 95:101149. [PMID: 36443219 PMCID: PMC10209355 DOI: 10.1016/j.preteyeres.2022.101149] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Revised: 11/12/2022] [Accepted: 11/17/2022] [Indexed: 11/27/2022]
Abstract
Wnt signaling comprises a group of complex signal transduction pathways that play critical roles in cell proliferation, differentiation, and apoptosis during development, as well as in stem cell maintenance and adult tissue homeostasis. Wnt pathways are classified into two major groups, canonical (β-catenin-dependent) or non-canonical (β-catenin-independent). Most previous studies in the eye have focused on canonical Wnt signaling, and the role of non-canonical signaling remains poorly understood. Additionally, the crosstalk between canonical and non-canonical Wnt signaling in the eye has hardly been explored. In this review, we present an overview of available data on ocular non-canonical Wnt signaling, including developmental and functional aspects in different eye compartments. We also discuss important changes of this signaling in various ocular conditions, such as keratoconus, aniridia-related keratopathy, diabetes, age-related macular degeneration, optic nerve damage, pathological angiogenesis, and abnormalities in the trabecular meshwork and conjunctival cells, and limbal stem cell deficiency.
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Affiliation(s)
- Ruchi Shah
- Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA; Regenerative Medicine Institute Eye Program, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Cynthia Amador
- Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA; Regenerative Medicine Institute Eye Program, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Steven T Chun
- Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA; Regenerative Medicine Institute Eye Program, Cedars-Sinai Medical Center, Los Angeles, CA, USA; University of California Los Angeles, Los Angeles, CA, USA
| | - Sean Ghiam
- Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA; Regenerative Medicine Institute Eye Program, Cedars-Sinai Medical Center, Los Angeles, CA, USA; Sackler School of Medicine, New York State/American Program of Tel Aviv University, Tel Aviv, Israel
| | - Mehrnoosh Saghizadeh
- Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA; Regenerative Medicine Institute Eye Program, Cedars-Sinai Medical Center, Los Angeles, CA, USA; David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | - Andrei A Kramerov
- Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA; Regenerative Medicine Institute Eye Program, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Alexander V Ljubimov
- Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA; Regenerative Medicine Institute Eye Program, Cedars-Sinai Medical Center, Los Angeles, CA, USA; David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA; Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
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11
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Wishart TFL, Lovicu FJ. Spatiotemporal Localisation of Heparan Sulphate Proteoglycans throughout Mouse Lens Morphogenesis. Cells 2023; 12:1364. [PMID: 37408198 DOI: 10.3390/cells12101364] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 05/05/2023] [Accepted: 05/09/2023] [Indexed: 07/07/2023] Open
Abstract
Heparan sulphate proteoglycans (HSPGs) consist of a core protein decorated with sulphated HS-glycosaminoglycan (GAG) chains. These negatively charged HS-GAG chains rely on the activity of PAPSS synthesising enzymes for their sulfation, which allows them to bind to and regulate the activity of many positively charged HS-binding proteins. HSPGs are found on the surfaces of cells and in the pericellular matrix, where they interact with various components of the cell microenvironment, including growth factors. By binding to and regulating ocular morphogens and growth factors, HSPGs are positioned to orchestrate growth factor-mediated signalling events that are essential for lens epithelial cell proliferation, migration, and lens fibre differentiation. Previous studies have shown that HS sulfation is essential for lens development. Moreover, each of the full-time HSPGs, differentiated by thirteen different core proteins, are differentially localised in a cell-type specific manner with regional differences in the postnatal rat lens. Here, the same thirteen HSPG-associated GAGs and core proteins as well as PAPSS2, are shown to be differentially regulated throughout murine lens development in a spatiotemporal manner. These findings suggest that HS-GAG sulfation is essential for growth factor-induced cellular processes during embryogenesis, and the unique and divergent localisation of different lens HSPG core proteins indicates that different HSPGs likely play specialized roles during lens induction and morphogenesis.
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Affiliation(s)
- Tayler F L Wishart
- Molecular and Cellular Biomedicine, School of Medical Sciences, The University of Sydney, Sydney, NSW 2006, Australia
| | - Frank J Lovicu
- Molecular and Cellular Biomedicine, School of Medical Sciences, The University of Sydney, Sydney, NSW 2006, Australia
- Save Sight Institute, The University of Sydney, Sydney, NSW 2006, Australia
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12
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Disatham J, Brennan L, Cvekl A, Kantorow M. Multiomics Analysis Reveals Novel Genetic Determinants for Lens Differentiation, Structure, and Transparency. Biomolecules 2023; 13:693. [PMID: 37189439 PMCID: PMC10136076 DOI: 10.3390/biom13040693] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 04/13/2023] [Accepted: 04/16/2023] [Indexed: 05/17/2023] Open
Abstract
Recent advances in next-generation sequencing and data analysis have provided new gateways for identification of novel genome-wide genetic determinants governing tissue development and disease. These advances have revolutionized our understanding of cellular differentiation, homeostasis, and specialized function in multiple tissues. Bioinformatic and functional analysis of these genetic determinants and the pathways they regulate have provided a novel basis for the design of functional experiments to answer a wide range of long-sought biological questions. A well-characterized model for the application of these emerging technologies is the development and differentiation of the ocular lens and how individual pathways regulate lens morphogenesis, gene expression, transparency, and refraction. Recent applications of next-generation sequencing analysis on well-characterized chicken and mouse lens differentiation models using a variety of omics techniques including RNA-seq, ATAC-seq, whole-genome bisulfite sequencing (WGBS), chip-seq, and CUT&RUN have revealed a wide range of essential biological pathways and chromatin features governing lens structure and function. Multiomics integration of these data has established new gene functions and cellular processes essential for lens formation, homeostasis, and transparency including the identification of novel transcription control pathways, autophagy remodeling pathways, and signal transduction pathways, among others. This review summarizes recent omics technologies applied to the lens, methods for integrating multiomics data, and how these recent technologies have advanced our understanding ocular biology and function. The approach and analysis are relevant to identifying the features and functional requirements of more complex tissues and disease states.
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Affiliation(s)
- Joshua Disatham
- Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL 33431, USA; (J.D.); (L.B.)
| | - Lisa Brennan
- Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL 33431, USA; (J.D.); (L.B.)
| | - Ales Cvekl
- Departments of Ophthalmology and Visual Sciences and Genetics, Albert Einstein College of Medicine, Bronx, NY 10461, USA;
| | - Marc Kantorow
- Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL 33431, USA; (J.D.); (L.B.)
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13
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FGF-2 Differentially Regulates Lens Epithelial Cell Behaviour during TGF-β-Induced EMT. Cells 2023; 12:cells12060827. [PMID: 36980168 PMCID: PMC10046997 DOI: 10.3390/cells12060827] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 03/02/2023] [Accepted: 03/06/2023] [Indexed: 03/11/2023] Open
Abstract
Fibroblast growth factor (FGF) and transforming growth factor-beta (TGF-β) can regulate and/or dysregulate lens epithelial cell (LEC) behaviour, including proliferation, fibre differentiation, and epithelial–mesenchymal transition (EMT). Earlier studies have investigated the crosstalk between FGF and TGF-β in dictating lens cell fate, that appears to be dose dependent. Here, we tested the hypothesis that a fibre-differentiating dose of FGF differentially regulates the behaviour of lens epithelial cells undergoing TGF-β-induced EMT. Postnatal 21-day-old rat lens epithelial explants were treated with a fibre-differentiating dose of FGF-2 (200 ng/mL) and/or TGF-β2 (50 pg/mL) over a 7-day culture period. We compared central LECs (CLECs) and peripheral LECs (PLECs) using immunolabelling for changes in markers for EMT (α-SMA), lens fibre differentiation (β-crystallin), epithelial cell adhesion (β-catenin), and the cytoskeleton (alpha-tropomyosin), as well as Smad2/3- and MAPK/ERK1/2-signalling. Lens epithelial explants cotreated with FGF-2 and TGF-β2 exhibited a differential response, with CLECs undergoing EMT while PLECs favoured more of a lens fibre differentiation response, compared to the TGF-β-only-treated explants where all cells in the explants underwent EMT. The CLECs cotreated with FGF and TGF-β immunolabelled for α-SMA, with minimal β-crystallin, whereas the PLECs demonstrated strong β-crystallin reactivity and little α-SMA. Interestingly, compared to the TGF-β-only-treated explants, α-SMA was significantly decreased in the CLECs cotreated with FGF/TGF-β. Smad-dependent and independent signalling was increased in the FGF-2/TGF-β2 co-treated CLECs, that had a heightened number of cells with nuclear localisation of Smad2/3 compared to the PLECs, that in contrast had more pronounced ERK1/2-signalling over Smad2/3 activation. The current study has confirmed that FGF-2 is influential in differentially regulating the behaviour of LECs during TGF-β-induced EMT, leading to a heterogenous cell population, typical of that observed in the development of post-surgical, posterior capsular opacification (PCO). This highlights the cooperative relationship between FGF and TGF-β leading to lens pathology, providing a different perspective when considering preventative measures for controlling PCO.
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14
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Upreti A, Padula SL, Tangeman JA, Wagner BD, O’Connell MJ, Jaquish TJ, Palko RK, Mantz CJ, Anand D, Lovicu FJ, Lachke SA, Robinson ML. Lens Epithelial Explants Treated with Vitreous Humor Undergo Alterations in Chromatin Landscape with Concurrent Activation of Genes Associated with Fiber Cell Differentiation and Innate Immune Response. Cells 2023; 12:501. [PMID: 36766843 PMCID: PMC9914805 DOI: 10.3390/cells12030501] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 01/31/2023] [Accepted: 01/31/2023] [Indexed: 02/05/2023] Open
Abstract
Lens epithelial explants are comprised of lens epithelial cells cultured in vitro on their native basement membrane, the lens capsule. Biologists have used lens epithelial explants to study many different cellular processes including lens fiber cell differentiation. In these studies, fiber differentiation is typically measured by cellular elongation and the expression of a few proteins characteristically expressed by lens fiber cells in situ. Chromatin and RNA was collected from lens epithelial explants cultured in either un-supplemented media or media containing 50% bovine vitreous humor for one or five days. Chromatin for ATAC-sequencing and RNA for RNA-sequencing was prepared from explants to assess regions of accessible chromatin and to quantitatively measure gene expression, respectively. Vitreous humor increased chromatin accessibility in promoter regions of genes associated with fiber differentiation and, surprisingly, an immune response, and this was associated with increased transcript levels for these genes. In contrast, vitreous had little effect on the accessibility of the genes highly expressed in the lens epithelium despite dramatic reductions in their mRNA transcripts. An unbiased analysis of differentially accessible regions revealed an enrichment of cis-regulatory motifs for RUNX, SOX and TEAD transcription factors that may drive differential gene expression in response to vitreous.
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Affiliation(s)
- Anil Upreti
- Cell, Molecular and Structural Biology Program, Miami University, Oxford, OH 45056, USA
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH 45056, USA
| | - Stephanie L. Padula
- Cell, Molecular and Structural Biology Program, Miami University, Oxford, OH 45056, USA
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH 45056, USA
| | - Jared A. Tangeman
- Cell, Molecular and Structural Biology Program, Miami University, Oxford, OH 45056, USA
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH 45056, USA
| | - Brad D. Wagner
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH 45056, USA
| | | | - Tycho J. Jaquish
- Cell, Molecular and Structural Biology Program, Miami University, Oxford, OH 45056, USA
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH 45056, USA
| | - Raye K. Palko
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH 45056, USA
| | - Courtney J. Mantz
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH 45056, USA
| | - Deepti Anand
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - Frank J. Lovicu
- Molecular and Cellular Biomedicine, School of Medical Sciences, and Save Sight Institute, The University of Sydney, Sydney, NSW 2006, Australia
| | - Salil A. Lachke
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
- Center for Bioinformatics and Computational Biology, University of Delaware, Newark, DE 19716, USA
| | - Michael L. Robinson
- Cell, Molecular and Structural Biology Program, Miami University, Oxford, OH 45056, USA
- Department of Biology and Center for Visual Sciences, Miami University, Oxford, OH 45056, USA
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15
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Wang X, Hui Q, Jin Z, Rao F, Jin L, Yu B, Banda J, Li X. Roles of growth factors in eye development and ophthalmic diseases. Zhejiang Da Xue Xue Bao Yi Xue Ban 2022; 51:613-625. [PMID: 36581579 PMCID: PMC10264994 DOI: 10.3724/zdxbyxb-2022-0603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 07/30/2022] [Indexed: 12/02/2022]
Abstract
Growth factors are active substances secreted by a variety of cells, which act as messengers to regulate cell migration, proliferation and differentiation. Many growth factors are involved in the eye development or the pathophysiological processes of eye diseases. Growth factors such as vascular endothelial growth factor and basic fibroblast growth factor mediate the occurrence and development of diabetic retinopathy, choroidal neovascularization, cataract, diabetic macular edema, and other retinal diseases. On the other hand, growth factors like nerve growth factor, ciliary neurotrophic factor, glial cell line-derived neurotrophic factor, pigment epithelial-derived factor and granulocyte colony-stimulating factor are known to promote optic nerve injury repair. Growth factors are also related to the pathogenesis of myopia. Fibroblast growth factor, transforming growth factor-β, and insulin-like growth factor regulate scleral thickness and influence the occurrence and development of myopia. This article reviews growth factors involved in ocular development and ocular pathophysiology, discusses the relationship between growth factors and ocular diseases, to provide reference for the application of growth factors in ophthalmology.
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16
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Drobek M. Paralogous Genes Involved in Embryonic Development: Lessons from the Eye and Other Tissues. Genes (Basel) 2022; 13:2082. [PMID: 36360318 PMCID: PMC9690401 DOI: 10.3390/genes13112082] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 10/23/2022] [Accepted: 11/05/2022] [Indexed: 07/09/2024] Open
Abstract
During evolution, gene duplications lead to a naturally increased gene dosage. Duplicated genes can be further retained or eliminated over time by purifying selection pressure. The retention probability is increased by functional diversification and by the acquisition of novel functions. Interestingly, functionally diverged paralogous genes can maintain a certain level of functional redundancy and at least a partial ability to replace each other. In such cases, diversification probably occurred at the level of transcriptional regulation. Nevertheless, some duplicated genes can maintain functional redundancy after duplication and the ability to functionally compensate for the loss of each other. Many of them are involved in proper embryonic development. The development of particular tissues/organs and developmental processes can be more or less sensitive to the overall gene dosage. Alterations in the gene dosage or a decrease below a threshold level may have dramatic phenotypic consequences or even lead to embryonic lethality. The number of functional alleles of particular paralogous genes and their mutual cooperation and interactions influence the gene dosage, and therefore, these factors play a crucial role in development. This review will discuss individual interactions between paralogous genes and gene dosage sensitivity during development. The eye was used as a model system, but other tissues are also included.
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Affiliation(s)
- Michaela Drobek
- Laboratory of Transcriptional Regulation, Institute of Molecular Genetics of the Czech Academy of Sciences, Videnska 1083, 142 20 Praha 4, Czech Republic
- Laboratory of RNA Biology, Institute of Molecular Genetics of the Czech Academy of Sciences, Videnska 1083, 142 20 Praha 4, Czech Republic
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17
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Cvekl A, Camerino MJ. Generation of Lens Progenitor Cells and Lentoid Bodies from Pluripotent Stem Cells: Novel Tools for Human Lens Development and Ocular Disease Etiology. Cells 2022; 11:3516. [PMID: 36359912 PMCID: PMC9658148 DOI: 10.3390/cells11213516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 10/31/2022] [Accepted: 11/02/2022] [Indexed: 11/09/2022] Open
Abstract
In vitro differentiation of human pluripotent stem cells (hPSCs) into specialized tissues and organs represents a powerful approach to gain insight into those cellular and molecular mechanisms regulating human development. Although normal embryonic eye development is a complex process, generation of ocular organoids and specific ocular tissues from pluripotent stem cells has provided invaluable insights into the formation of lineage-committed progenitor cell populations, signal transduction pathways, and self-organization principles. This review provides a comprehensive summary of recent advances in generation of adenohypophyseal, olfactory, and lens placodes, lens progenitor cells and three-dimensional (3D) primitive lenses, "lentoid bodies", and "micro-lenses". These cells are produced alone or "community-grown" with other ocular tissues. Lentoid bodies/micro-lenses generated from human patients carrying mutations in crystallin genes demonstrate proof-of-principle that these cells are suitable for mechanistic studies of cataractogenesis. Taken together, current and emerging advanced in vitro differentiation methods pave the road to understand molecular mechanisms of cataract formation caused by the entire spectrum of mutations in DNA-binding regulatory genes, such as PAX6, SOX2, FOXE3, MAF, PITX3, and HSF4, individual crystallins, and other genes such as BFSP1, BFSP2, EPHA2, GJA3, GJA8, LIM2, MIP, and TDRD7 represented in human cataract patients.
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Affiliation(s)
- Aleš Cvekl
- Departments Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY 10461, USA
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Michael John Camerino
- Departments Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY 10461, USA
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY 10461, USA
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18
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Conti E, Harschnitz O. Human stem cell models to study placode development, function and pathology. Development 2022; 149:276462. [DOI: 10.1242/dev.200831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
ABSTRACT
Placodes are embryonic structures originating from the rostral ectoderm that give rise to highly diverse organs and tissues, comprising the anterior pituitary gland, paired sense organs and cranial sensory ganglia. Their development, including the underlying gene regulatory networks and signalling pathways, have been for the most part characterised in animal models. In this Review, we describe how placode development can be recapitulated by the differentiation of human pluripotent stem cells towards placode progenitors and their derivatives, highlighting the value of this highly scalable platform as an optimal in vitro tool to study the development of human placodes, and identify human-specific mechanisms in their development, function and pathology.
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Affiliation(s)
- Eleonora Conti
- Neurogenomics Research Centre, Human Technopole , Viale Rita Levi-Montalcini, 1, 20157 Milan , Italy
| | - Oliver Harschnitz
- Neurogenomics Research Centre, Human Technopole , Viale Rita Levi-Montalcini, 1, 20157 Milan , Italy
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19
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Disatham J, Brennan L, Jiao X, Ma Z, Hejtmancik JF, Kantorow M. Changes in DNA methylation hallmark alterations in chromatin accessibility and gene expression for eye lens differentiation. Epigenetics Chromatin 2022; 15:8. [PMID: 35246225 PMCID: PMC8897925 DOI: 10.1186/s13072-022-00440-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 02/16/2022] [Indexed: 12/13/2022] Open
Abstract
Background Methylation at cytosines (mCG) is a well-known regulator of gene expression, but its requirements for cellular differentiation have yet to be fully elucidated. A well-studied cellular differentiation model system is the eye lens, consisting of a single anterior layer of epithelial cells that migrate laterally and differentiate into a core of fiber cells. Here, we explore the genome-wide relationships between mCG methylation, chromatin accessibility and gene expression during differentiation of eye lens epithelial cells into fiber cells. Results Whole genome bisulfite sequencing identified 7621 genomic loci exhibiting significant differences in mCG levels between lens epithelial and fiber cells. Changes in mCG levels were inversely correlated with the differentiation state-specific expression of 1285 genes preferentially expressed in either lens fiber or lens epithelial cells (Pearson correlation r = − 0.37, p < 1 × 10–42). mCG levels were inversely correlated with chromatin accessibility determined by assay for transposase-accessible sequencing (ATAC-seq) (Pearson correlation r = − 0.86, p < 1 × 10–300). Many of the genes exhibiting altered regions of DNA methylation, chromatin accessibility and gene expression levels in fiber cells relative to epithelial cells are associated with lens fiber cell structure, homeostasis and transparency. These include lens crystallins (CRYBA4, CRYBB1, CRYGN, CRYBB2), lens beaded filament proteins (BFSP1, BFSP2), transcription factors (HSF4, SOX2, HIF1A), and Notch signaling pathway members (NOTCH1, NOTCH2, HEY1, HES5). Analysis of regions exhibiting cell-type specific alterations in DNA methylation revealed an overrepresentation of consensus sequences of multiple transcription factors known to play key roles in lens cell differentiation including HIF1A, SOX2, and the MAF family of transcription factors. Conclusions Collectively, these results link DNA methylation with control of chromatin accessibility and gene expression changes required for eye lens differentiation. The results also point to a role for DNA methylation in the regulation of transcription factors previously identified to be important for lens cell differentiation. Supplementary Information The online version contains supplementary material available at 10.1186/s13072-022-00440-z.
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Affiliation(s)
- Joshua Disatham
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL, USA
| | - Lisa Brennan
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL, USA
| | - Xiaodong Jiao
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, MD, USA
| | - Zhiwei Ma
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, MD, USA
| | - J Fielding Hejtmancik
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, MD, USA
| | - Marc Kantorow
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL, USA.
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20
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Makrides N, Wang Q, Tao C, Schwartz S, Zhang X. Jack of all trades, master of each: the diversity of fibroblast growth factor signalling in eye development. Open Biol 2022; 12:210265. [PMID: 35016551 PMCID: PMC8753161 DOI: 10.1098/rsob.210265] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
A central question in development biology is how a limited set of signalling pathways can instruct unlimited diversity of multicellular organisms. In this review, we use three ocular tissues as models of increasing complexity to present the astounding versatility of fibroblast growth factor (FGF) signalling. In the lacrimal gland, we highlight the specificity of FGF signalling in a one-dimensional model of budding morphogenesis. In the lens, we showcase the dynamics of FGF signalling in altering functional outcomes in a two-dimensional space. In the retina, we present the prolific utilization of FGF signalling from three-dimensional development to homeostasis. These examples not only shed light on the cellular basis for the perfection and complexity of ocular development, but also serve as paradigms for the diversity of FGF signalling.
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Affiliation(s)
- Neoklis Makrides
- Departments of Ophthalmology and Pathology and Cell Biology, Columbia University, New York, NY, USA
| | - Qian Wang
- Departments of Ophthalmology and Pathology and Cell Biology, Columbia University, New York, NY, USA
| | - Chenqi Tao
- Departments of Ophthalmology and Pathology and Cell Biology, Columbia University, New York, NY, USA
| | - Samuel Schwartz
- Departments of Ophthalmology and Pathology and Cell Biology, Columbia University, New York, NY, USA
| | - Xin Zhang
- Departments of Ophthalmology and Pathology and Cell Biology, Columbia University, New York, NY, USA
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21
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Wishart TFL, Lovicu FJ. An Atlas of Heparan Sulfate Proteoglycans in the Postnatal Rat Lens. Invest Ophthalmol Vis Sci 2021; 62:5. [PMID: 34730792 PMCID: PMC8572486 DOI: 10.1167/iovs.62.14.5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Purpose The arrangement of lens cells is regulated by ocular growth factors. Although the effects of these inductive molecules on lens cell behavior (proliferation, survival, and fiber differentiation) are well-characterized, the precise mechanisms underlying the regulation of growth factor-mediated signaling in lens remains elusive. Increasing evidence highlights the importance of heparan sulfate proteoglycans (HSPGs) for the signaling regulation of growth factors; however, the identity of the different lens HSPGs and the specific roles they play in lens biology are still unknown. Methods Semiquantitative real-time (RT)‐PCR and immunolabeling were used to characterize the spatial distribution of all known HSPG core proteins and their associated glycosaminoglycans (heparan and chondroitin sulfate) in the postnatal rat lens. Fibroblast growth factor (FGF)-2-treated lens epithelial explants, cultured in the presence of Surfen (an inhibitor of heparan sulfate [HS]-growth factor binding interactions) were used to investigate the requirement for HS in FGF-2-induced proliferation, fiber differentiation, and ERK1/2-signaling. Results The lens expresses all HSPGs. These HSPGs are differentially localized to distinct functional regions of the lens. In vitro, inhibition of HS-sulfation with Surfen blocked FGF-2-mediated ERK1/2-signaling associated with lens epithelial cell proliferation and fiber differentiation, highlighting that these cellular processes are dependent on HS. Conclusions These findings support a requirement for HSPGs in FGF-2 driven lens cell proliferation and fiber differentiation. The identification of specific HSPG core proteins in key functional lens regions, and the divergent expression patterns of closely related HSPGs, suggests that different HSPGs may differentially regulate growth factor signaling networks leading to specific biological events involved in lens growth and maintenance.
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Affiliation(s)
- Tayler F L Wishart
- School of Medical Sciences, The University of Sydney, New South Wales, Australia
| | - Frank J Lovicu
- School of Medical Sciences, The University of Sydney, New South Wales, Australia.,Save Sight Institute, The University of Sydney, New South Wales, Australia
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22
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Shu DY, Lovicu FJ. Insights into Bone Morphogenetic Protein-(BMP-) Signaling in Ocular Lens Biology and Pathology. Cells 2021; 10:cells10102604. [PMID: 34685584 PMCID: PMC8533954 DOI: 10.3390/cells10102604] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 09/27/2021] [Accepted: 09/28/2021] [Indexed: 01/23/2023] Open
Abstract
Bone morphogenetic proteins (BMPs) are a diverse class of growth factors that belong to the transforming growth factor-beta (TGFβ) superfamily. Although originally discovered to possess osteogenic properties, BMPs have since been identified as critical regulators of many biological processes, including cell-fate determination, cell proliferation, differentiation and morphogenesis, throughout the body. In the ocular lens, BMPs are important in orchestrating fundamental developmental processes such as induction of lens morphogenesis, and specialized differentiation of its fiber cells. Moreover, BMPs have been reported to facilitate regeneration of the lens, as well as abrogate pathological processes such as TGFβ-induced epithelial-mesenchymal transition (EMT) and apoptosis. In this review, we summarize recent insights in this topic and discuss the complexities of BMP-signaling including the role of individual BMP ligands, receptors, extracellular antagonists and cross-talk between canonical and non-canonical BMP-signaling cascades in the lens. By understanding the molecular mechanisms underlying BMP activity, we can advance their potential therapeutic role in cataract prevention and lens regeneration.
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Affiliation(s)
- Daisy Y. Shu
- Department of Ophthalmology, Schepens Eye Research Institute of Mass Eye and Ear, Harvard Medical School, Boston, MA 02114, USA;
| | - Frank J. Lovicu
- School of Medical Sciences, The University of Sydney, Sydney, NSW 2006, Australia
- Save Sight Institute, The University of Sydney, Sydney, NSW 2000, Australia
- Correspondence: ; Tel.: +61-2-9351-5170
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23
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Kessel L, Bach-Holm D, Al-Bakri M, Roos L, Lund A, Grønskov K. Genetic disease is a common cause of bilateral childhood cataract in Denmark. Ophthalmic Genet 2021; 42:650-658. [PMID: 34169787 DOI: 10.1080/13816810.2021.1941128] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Purpose: Bilateral childhood cataracts can be caused by a metabolic disease, constitute a part of a syndrome, run in families, be sporadic or iatrogenic. The amount of work-up needed to establish a cause is discussed and the aim of the present study was to evaluate causes of bilateral childhood cataract.Methods: Chart review of 211 Danish children with bilateral cataracts. Information on work-up was retrieved with special focus on general health, metabolic screening, evaluation for congenital infections and genetic testing.Results: Cataract was seen in combination with systemic disease in 40.8%, 29.4% had hereditary cataracts, 27.0% had isolated cataract, in 1.4% it was associated with ocular malformations and 1.4% had been born prematurely without any other sequelae than the cataract. A genetic cause could be demonstrated in 74 children.Conclusion: Systemic comorbidities are very common in children with cataract and are not always known prior to the diagnosis of cataract. Genetic evaluation, especially targeted analyses, provided a molecular genetic diagnosis in a large proportion of those tested but it also failed to provide a molecular genetic diagnosis in some patients with a family history suggesting autosomal dominant inheritance. Most importantly, in some patients, genetic work-up provided a diagnosis in patients where it had therapeutic consequences and where the systemic disease would have caused irreversible damage, had it not been treated timely. Given the high prevalence of systemic disease, it seems advisable to co-manage children with bilateral cataracts with a pediatrician and to include genetic evaluation as part of the work-up.
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Affiliation(s)
- Line Kessel
- Department of Ophthalmology, Rigshospitalet, Copenhagen, Denmark.,Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Daniella Bach-Holm
- Department of Ophthalmology, Rigshospitalet, Copenhagen, Denmark.,Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Moug Al-Bakri
- Department of Ophthalmology, Rigshospitalet, Copenhagen, Denmark
| | - Laura Roos
- Departments of Clinical Genetics and Paediatrics, Rigshospitalet, Copenhagen, Denmark
| | - Allan Lund
- Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark.,Centre for Inherited Metabolic Diseases, Department of Paediatrics and Clinical Genetics, Rigshospitalet, Copenhagen, Denmark
| | - Karen Grønskov
- Departments of Clinical Genetics and Paediatrics, Rigshospitalet, Copenhagen, Denmark
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24
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Gu Y, Yao K, Fu Q. Lens regeneration: scientific discoveries and clinical possibilities. Mol Biol Rep 2021; 48:4911-4923. [PMID: 34143397 DOI: 10.1007/s11033-021-06489-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Accepted: 06/08/2021] [Indexed: 12/11/2022]
Abstract
In the process of exploring new methods for cataract treatment, lens regeneration is an ideal strategy for effectively restoring accommodative vision and avoiding postoperative complications and has great clinical potential. Lens regeneration, which is not a simple repetition of lens development, depends on the complex regulatory network comprising the FGF, BMP/TGF-β, Notch, and Wnt signaling pathways. Current research mainly focuses on in situ and in vitro lens regeneration. On the one hand, the possibility of the autologous stem cell in situ regeneration of functional lenses has been confirmed; on the other hand, both embryonic stem cells and induced pluripotent stem cells have been induced into lentoid bodies in vitro which are similar to the natural lens to a certain extent. This article will briefly summarize the regulatory mechanisms of lens development, describe the recent progress of lens regeneration, explore the key molecular signaling pathways, and, more importantly, discuss the prospects and challenges of their clinical applications to provide reference for clinical transformations.
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Affiliation(s)
- Yuzhou Gu
- Eye Center of the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310009, Zhejiang Province, China.,Zhejiang Provincial Key Lab of Ophthalmology, Hangzhou, 310009, Zhejiang Province, China
| | - Ke Yao
- Eye Center of the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310009, Zhejiang Province, China. .,Zhejiang Provincial Key Lab of Ophthalmology, Hangzhou, 310009, Zhejiang Province, China.
| | - Qiuli Fu
- Eye Center of the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310009, Zhejiang Province, China. .,Zhejiang Provincial Key Lab of Ophthalmology, Hangzhou, 310009, Zhejiang Province, China.
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25
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Faranda AP, Shihan MH, Wang Y, Duncan MK. The aging mouse lens transcriptome. Exp Eye Res 2021; 209:108663. [PMID: 34119483 DOI: 10.1016/j.exer.2021.108663] [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: 03/18/2021] [Revised: 05/04/2021] [Accepted: 06/01/2021] [Indexed: 02/06/2023]
Abstract
Age is a major risk factor for cataract (ARC). However, the influence of aging on the lens transcriptome is under studied. Lens epithelial (LEC) and fiber cells (LFC) were isolated from young (3 month old) and aged (24 month old) C57BL/6J mice, and the transcriptome elucidated via RNAseq. EdgeR estimated differential gene expression in pairwise contrasts, and Advaita's Ipathway guide and custom R scripts were used to evaluate the potential biological significance of differentially expressed genes (DEGs). This analysis revealed age-dependent decreases in lens differentiation marker expression in both LECs and LFCs, with gamma crystallin transcripts downregulating nearly 50 fold in aged LFCs. The expression of the transcription factors Hsf4 and Maf, which are known to activate lens fiber cell preferred genes, are downregulated, while FoxE3, which represses gamma crystallin expression, is upregulated in aged fibers. Aged LECs upregulate genes controlling the immune response, complement pathways, and cellular stress responses, including glutathione peroxidase 3 (Gpx3). Aged LFCs exhibit broad changes in the expression of genes regulating cell communication, and upregulate genes involved in antigen processing/presentation and cholesterol metabolism, while changes in the expression of mitochondrial respiratory chain genes are consistent with mitochondrial stress, including upregulation of NDufa4l2, which encodes an alternate electron transport chain protein. However, age did not profoundly affect the response of LECs to injury as both young and aged LECs upregulate inflammatory gene signatures at 24 h post injury to similar extents. These RNAseq profiles provide a rich data set that can be mined to understand the genetic regulation of lens aging and how this impinges on the pathophysiology of age related cataract.
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Affiliation(s)
- Adam P Faranda
- Department of Biological Sciences University of Delaware Newark, DE, 19716, USA
| | - Mahbubul H Shihan
- Department of Biological Sciences University of Delaware Newark, DE, 19716, USA
| | - Yan Wang
- Department of Biological Sciences University of Delaware Newark, DE, 19716, USA
| | - Melinda K Duncan
- Department of Biological Sciences University of Delaware Newark, DE, 19716, USA.
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26
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Lens fiber cell differentiation occurs independently of fibroblast growth factor receptor signaling in the absence of Pten. Dev Biol 2020; 467:1-13. [PMID: 32858001 DOI: 10.1016/j.ydbio.2020.07.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 07/30/2020] [Accepted: 07/31/2020] [Indexed: 11/21/2022]
Abstract
Fibroblast growth factor receptor (FGFR) signaling patterns multiple tissues in both vertebrates and invertebrates, largely through the activation of intracellular kinases. Recent studies have demonstrated that the phosphatase, PTEN negatively regulates FGFR signaling, such that the loss of PTEN can compensate for reduced FGFR signaling to rescue aspects of normal development. In the developing mouse lens, FGFR signaling promotes cell survival and fiber cell differentiation, and the loss of Pten largely compensates for the loss of Fgfr2 during lens development. To explore this regulatory relationship further, we focused on the phenotypic consequences of Pten loss on lens development and fiber cell differentiation in the absence of all FGFR signaling, both in vivo and in lens epithelial explants. Pten deletion partially rescues primary fiber cell elongation and γ-crystallin accumulation in FGFR-deficient lenses in vivo but fails to rescue cell survival or proliferation. However, in lens epithelial explants, where cells survive without FGFR signaling, Pten deletion rescues vitreous humor-induced lens fiber cell differentiation in the combined absence of Fgfr1, Fgfr2 and Fgfr3. This represents the first evidence that vitreous-initiated signaling cascades, independent of FGFR signaling, can drive mammalian lens fiber cell differentiation, when freed from repression by PTEN.
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27
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Garg A, Hannan A, Wang Q, Makrides N, Zhong J, Li H, Yoon S, Mao Y, Zhang X. Etv transcription factors functionally diverge from their upstream FGF signaling in lens development. eLife 2020; 9:e51915. [PMID: 32043969 PMCID: PMC7069720 DOI: 10.7554/elife.51915] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 02/10/2020] [Indexed: 12/12/2022] Open
Abstract
The signal regulated transcription factors (SRTFs) control the ultimate transcriptional output of signaling pathways. Here, we examined a family of FGF-induced SRTFs - Etv1, Etv 4, and Etv 5 - in murine lens development. Contrary to FGF receptor mutants that displayed loss of ERK signaling and defective cell differentiation, Etv deficiency augmented ERK phosphorylation without disrupting the normal lens fiber gene expression. Instead, the transitional zone for lens differentiation was shifted anteriorly as a result of reduced Jag1-Notch signaling. We also showed that Etv proteins suppresses mTOR activity by promoting Tsc2 expression, which is necessary for the nuclei clearance in mature lens. These results revealed the functional divergence between Etv and FGF in lens development, demonstrating that these SRTFs can operate outside the confine of their upstream signaling.
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Affiliation(s)
- Ankur Garg
- Department of Ophthalmology, Columbia UniversityNew YorkUnited States
- Department of Pathology and Cell Biology, Columbia UniversityNew YorkUnited States
| | - Abdul Hannan
- Department of Ophthalmology, Columbia UniversityNew YorkUnited States
- Department of Pathology and Cell Biology, Columbia UniversityNew YorkUnited States
| | - Qian Wang
- Department of Ophthalmology, Columbia UniversityNew YorkUnited States
- Department of Pathology and Cell Biology, Columbia UniversityNew YorkUnited States
| | - Neoklis Makrides
- Department of Ophthalmology, Columbia UniversityNew YorkUnited States
- Department of Pathology and Cell Biology, Columbia UniversityNew YorkUnited States
| | - Jian Zhong
- Burke Neurological Institute and Feil Family Brain and Mind Research Institute, Weill Cornell MedicineWhite PlainsUnited States
| | - Hongge Li
- Department of Ophthalmology, Columbia UniversityNew YorkUnited States
- Department of Pathology and Cell Biology, Columbia UniversityNew YorkUnited States
| | - Sungtae Yoon
- Department of Ophthalmology, Columbia UniversityNew YorkUnited States
- Department of Pathology and Cell Biology, Columbia UniversityNew YorkUnited States
| | - Yingyu Mao
- Department of Ophthalmology, Columbia UniversityNew YorkUnited States
- Department of Pathology and Cell Biology, Columbia UniversityNew YorkUnited States
| | - Xin Zhang
- Department of Ophthalmology, Columbia UniversityNew YorkUnited States
- Department of Pathology and Cell Biology, Columbia UniversityNew YorkUnited States
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28
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Fujino M, Tagami A, Ojima M, Mizuno S, Abdellatif AM, Kuno A, Takahashi S. c-MAF deletion in adult C57BL/6J mice induces cataract formation and abnormal differentiation of lens fiber cells. Exp Anim 2020; 69:242-249. [PMID: 31969519 PMCID: PMC7220708 DOI: 10.1538/expanim.19-0137] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
The transcription factor c-MAF is a member of the large MAF family, members of which possess transactivation and bZIP domains. c-MAF plays an important role in lens formation, T-lymphocyte differentiation, hypertrophic chondrocyte differentiation, and kidney development in mouse embryos. However, because homozygous deletion of c-Maf in C57BL/6J mice causes embryonic lethality, the functions of c-MAF in adult mice remain largely uninvestigated. To address this issue, we generated c-Maf floxed (c-Maffl/fl) C57BL/6J mice and established tamoxifen-inducible c-Maf knockout mice (c-Maffl/fl; CAG-Cre-ERTM mice, c-MafΔTAM). After tamoxifen injection, adult c-MafΔTAM mice showed successful deletion of c-Maf protein and developed severe cataracts; cataracts are also seen in human patients who have mutations in the c-MAF DNA binding domain. Furthermore, adult c-MafΔTAM mice exhibited abnormal lens structure and impaired differentiation of lens fiber cells. In summary, we established c-Maffl/fl and c-MafΔTAM C57BL/6J mice, which can be useful animal models for the investigation of c-MAF function in various developmental stages and can also be used as a disease model for cataracts.
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Affiliation(s)
- Mitsunori Fujino
- Department of Anatomy and Embryology, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan.,Ph.D. Program in Human Biology, School of Integrative and Global Majors, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan
| | - Asuka Tagami
- Department of Anatomy and Embryology, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan
| | - Masami Ojima
- Laboratory Animal Resource Center (LARC), University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan
| | - Seiya Mizuno
- Laboratory Animal Resource Center (LARC), University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan
| | - Ahmed M Abdellatif
- Department of Anatomy and Embryology, Faculty of Veterinary Medicine, Mansoura University, Mansoura 35516, Egypt
| | - Akihiro Kuno
- Department of Anatomy and Embryology, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan
| | - Satoru Takahashi
- Department of Anatomy and Embryology, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan.,Laboratory Animal Resource Center (LARC), University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan.,Life Science Center, Tsukuba Advanced Research Alliance (TARA), University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan.,International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan.,Transborder Medical Research Center, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan
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29
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Martynova E, Zhao Y, Xie Q, Zheng D, Cvekl A. Transcriptomic analysis and novel insights into lens fibre cell differentiation regulated by Gata3. Open Biol 2019; 9:190220. [PMID: 31847788 PMCID: PMC6936257 DOI: 10.1098/rsob.190220] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Gata3 is a DNA-binding transcription factor involved in cellular differentiation in a variety of tissues including inner ear, hair follicle, kidney, mammary gland and T-cells. In a previous study in 2009, Maeda et al. (Dev. Dyn.238, 2280–2291; doi:10.1002/dvdy.22035) found that Gata3 mutants could be rescued from midgestational lethality by the expression of a Gata3 transgene in sympathoadrenal neuroendocrine cells. The rescued embryos clearly showed multiple defects in lens fibre cell differentiation. To determine whether these defects were truly due to the loss of Gata3 expression in the lens, we generated a lens-specific Gata3 loss-of-function model. Analogous to the previous findings, our Gata3 null embryos showed abnormal regulation of cell cycle exit during lens fibre cell differentiation, marked by reduction in the expression of the cyclin-dependent kinase inhibitors Cdkn1b/p27 and Cdkn1c/p57, and the retention of nuclei accompanied by downregulation of Dnase IIβ. Comparisons of transcriptomes between control and mutated lenses by RNA-Seq revealed dysregulation of lens-specific crystallin genes and intermediate filament protein Bfsp2. Both Cdkn1b/p27 and Cdkn1c/p57 loci are occupied in vivo by Gata3, as well as Prox1 and c-Jun, in lens chromatin. Collectively, our studies suggest that Gata3 regulates lens differentiation through the direct regulation of the Cdkn1b/p27and Cdkn1c/p57 expression, and the direct/or indirect transcriptional control of Bfsp2 and Dnase IIβ.
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Affiliation(s)
- Elena Martynova
- Departments of Ophthalmology and Visual Sciences and Genetics, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Yilin Zhao
- Departments of Ophthalmology and Visual Sciences and Genetics, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Qing Xie
- Departments of Ophthalmology and Visual Sciences and Genetics, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Deyou Zheng
- Departments of Genetics, Neurology, and Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Ales Cvekl
- Departments of Ophthalmology and Visual Sciences and Genetics, Albert Einstein College of Medicine, Bronx, NY 10461, USA
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30
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Padula SL, Anand D, Hoang TV, Chaffee BR, Liu L, Liang C, Lachke SA, Robinson ML. High-throughput transcriptome analysis reveals that the loss of Pten activates a novel NKX6-1/RASGRP1 regulatory module to rescue microphthalmia caused by Fgfr2-deficient lenses. Hum Genet 2019; 138:1391-1407. [PMID: 31691004 DOI: 10.1007/s00439-019-02084-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Accepted: 10/28/2019] [Indexed: 01/17/2023]
Abstract
FGFR signaling is critical to development and disease pathogenesis, initiating phosphorylation-driven signaling cascades, notably the RAS-RAF-MEK-ERK and PI3 K-AKT cascades. PTEN antagonizes FGFR signaling by reducing AKT and ERK activation. Mouse lenses lacking FGFR2 exhibit microphakia and reduced ERK and AKT phosphorylation, widespread apoptosis, and defective lens fiber cell differentiation. In contrast, simultaneous deletion of both Fgfr2 and Pten restores ERK and AKT activation levels as well as lens size, cell survival and aspects of fiber cell differentiation; however, the molecular basis of this "rescue" remains undefined. We performed transcriptomic analysis by RNA sequencing of mouse lenses with conditional deletion of Fgfr2, Pten or both Fgfr2 and Pten, which reveal new molecular mechanisms that uncover how FGFR2 and PTEN signaling interact during development. The FGFR2-deficient lens transcriptome demonstrates overall loss of fiber cell identity with deregulated expression of 1448 genes. We find that ~ 60% of deregulated genes return to normal expression levels in lenses lacking both Fgfr2 and Pten. Further, application of customized filtering parameters to these RNA-seq data sets identified 68 high-priority candidate genes. Bioinformatics analyses showed that the cis-binding motif of a high-priority homeodomain transcription factor, NKX6-1, was present in the putative promoters of ~ 78% of these candidates. Finally, biochemical reporter assays demonstrate that NKX6-1 activated the expression of the high-priority candidate Rasgrp1, a RAS-activating protein. Together, these data define a novel regulatory module in which NKX6-1 directly activates Rasgrp1 expression to restore the balance of ERK and AKT activation, thus providing new insights into alternate regulation of FGFR downstream events.
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Affiliation(s)
| | - Deepti Anand
- Department of Biological Sciences, University of Delaware, Newark, DE, USA
| | - Thanh V Hoang
- Department of Biology, Miami University, Oxford, OH, 45056, USA.,Department of Neuroscience, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Blake R Chaffee
- Department of Biology, Miami University, Oxford, OH, 45056, USA
| | - Lin Liu
- Department of Biology, Miami University, Oxford, OH, 45056, USA
| | - Chun Liang
- Department of Biology, Miami University, Oxford, OH, 45056, USA
| | - Salil A Lachke
- Department of Biological Sciences, University of Delaware, Newark, DE, USA.,Center for Bioinformatics and Computational Biology, University of Delaware, Newark, DE, USA
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31
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Leerberg DM, Hopton RE, Draper BW. Fibroblast Growth Factor Receptors Function Redundantly During Zebrafish Embryonic Development. Genetics 2019; 212:1301-1319. [PMID: 31175226 PMCID: PMC6707458 DOI: 10.1534/genetics.119.302345] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 05/29/2019] [Indexed: 01/08/2023] Open
Abstract
Fibroblast growth factor (Fgf) signaling regulates many processes during development. In most cases, one tissue layer secretes an Fgf ligand that binds and activates an Fgf receptor (Fgfr) expressed by a neighboring tissue. Although studies have identified the roles of specific Fgf ligands during development, less is known about the requirements for the receptors. We have generated null mutations in each of the five fgfr genes in zebrafish. Considering the diverse requirements for Fgf signaling throughout development, and that null mutations in the mouse Fgfr1 and Fgfr2 genes are embryonic lethal, it was surprising that all zebrafish homozygous mutants are viable and fertile, with no discernable embryonic defect. Instead, we find that multiple receptors are involved in coordinating most Fgf-dependent developmental processes. For example, mutations in the ligand fgf8a cause loss of the midbrain-hindbrain boundary, whereas, in the fgfr mutants, this phenotype is seen only in embryos that are triple mutant for fgfr1a;fgfr1b;fgfr2, but not in any single or double mutant combinations. We show that this apparent fgfr redundancy is also seen during the development of several other tissues, including posterior mesoderm, pectoral fins, viscerocranium, and neurocranium. These data are an essential step toward defining the specific Fgfrs that function with particular Fgf ligands to regulate important developmental processes in zebrafish.
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Affiliation(s)
- Dena M Leerberg
- Department of Molecular and Cellular Biology, University of California, Davis, California 95616
| | - Rachel E Hopton
- Department of Molecular and Cellular Biology, University of California, Davis, California 95616
| | - Bruce W Draper
- Department of Molecular and Cellular Biology, University of California, Davis, California 95616
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32
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Sundaresan L, Kumar P, Manivannan J, Balaguru UM, Kasiviswanathan D, Veeriah V, Anishetty S, Chatterjee S. Thalidomide and Its Analogs Differentially Target Fibroblast Growth Factor Receptors: Thalidomide Suppresses FGFR Gene Expression while Pomalidomide Dampens FGFR2 Activity. Chem Res Toxicol 2019; 32:589-602. [PMID: 30834740 DOI: 10.1021/acs.chemrestox.8b00286] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Thalidomide is an infamous teratogen and it is continuously being explored for its anticancer properties. Fibroblast growth factor receptors (FGFRs) are implicated in embryo development and cancer pathophysiology. With striking similarities observed between FGFR implicated conditions and thalidomide embryopathy, we hypothesized thalidomide targets FGFRs. We utilized three different cell lines and chicken embryo model to investigate the effects of thalidomide and analogs on FGFR expression. We performed molecular docking, KINOMEscan analysis, and kinase activity assays to study the drug-protein interactions. The expression of FGFR1 and FGFR2 was differentially regulated by all the three drugs in cells as well as in developing organs. Transcriptome analysis of thalidomide-treated chick embryo strongly suggests the modulation of FGFR signaling and key transcription factors. Corroboration with previous studies suggests that thalidomide might affect FGFR expression through the transcription factor, E2F1. At the protein level, molecular docking predicted all three analogs to interact with lysine residue at 517th and 508th positions of FGFR2 and FGFR3, respectively. This lysine coordinates the ATP binding site of FGFR, thus hinting at the possible perturbation of FGFR activity by thalidomide. Kinome analysis revealed that kinase activities of FGFR2 and FGFR3 (G697C) reduced by 31% and 65%, respectively, in the presence of 10 μM thalidomide. Further, we checked and confirmed that the analogs inhibited the FGFR2 kinase activity in a dose-dependent manner. This study suggests that FGFRs could be potential targets of thalidomide and the two analogs, and also endorses the link between the teratogenicity and antitumor activities of the drugs.
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33
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Lens differentiation is controlled by the balance between PDGF and FGF signaling. PLoS Biol 2019; 17:e3000133. [PMID: 30716082 PMCID: PMC6375662 DOI: 10.1371/journal.pbio.3000133] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Revised: 02/14/2019] [Accepted: 01/17/2019] [Indexed: 12/15/2022] Open
Abstract
How multiple receptor tyrosine kinases coordinate cell fate determination is yet to be elucidated. We show here that the receptor for platelet-derived growth factor (PDGF) signaling recruits the p85 subunit of Phosphoinositide 3-kinase (PI3K) to regulate mammalian lens development. Activation of PI3K signaling not only prevents B-cell lymphoma 2 (BCL2)-Associated X (Bax)- and BCL2 Antagonist/Killer (Bak)-mediated apoptosis but also promotes Notch signaling to prevent premature cell differentiation. Reducing PI3K activity destabilizes the Notch intracellular domain, while the constitutive activation of Notch reverses the PI3K deficiency phenotype. In contrast, fibroblast growth factor receptors (FGFRs) recruit Fibroblast Growth Factor Receptor Substrate 2 (Frs2) and Rous sarcoma oncogene (Src) Homology Phosphatase 2 (Shp2) to activate Mitogen-Activated Protein Kinase (MAPK) signaling, which induces the Notch ligand Jagged 1 (Jag1) and promotes cell differentiation. Inactivation of Shp2 restored the proper timing of differentiation in the p85 mutant lens, demonstrating the antagonistic interaction between FGF-induced MAPK and PDGF-induced PI3K signaling. By selective activation of PI3K and MAPK, PDGF and FGF cooperate with and oppose each other to balance progenitor cell maintenance and differentiation. A central aim in understanding cell signaling is to decode the cellular logic that underlies the functional specificity of growth factors. Although these factors are known to activate a common set of intracellular pathways, they nevertheless play specific roles in development and physiology. Using lens development in mice as a model, we show that fibroblast growth factor (FGF) and platelet-derived growth factor (PDGF) antagonize each other through their intrinsic biases toward distinct downstream targets. While FGF primarily induces the Ras–Mitogen-Activated Protein Kinase (MAPK) axis to promote lens cell differentiation, PDGF preferentially stimulates Phosphoinositide 3-kinase (PI3K) to enhance Notch signaling, which is necessary for maintaining the lens progenitor cell pool. By revealing the intricate interactions between PDGF, FGF, and Notch, we present a paradigm for how signaling crosstalk enables balanced growth and differentiation in multicellular organisms.
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VanSlyke JK, Boswell BA, Musil LS. Fibronectin regulates growth factor signaling and cell differentiation in primary lens cells. J Cell Sci 2018; 131:jcs.217240. [PMID: 30404825 DOI: 10.1242/jcs.217240] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 09/23/2018] [Indexed: 12/30/2022] Open
Abstract
Lens epithelial cells are bound to the lens extracellular matrix capsule, of which laminin is a major component. After cataract surgery, surviving lens epithelial cells are exposed to increased levels of fibronectin, and so we addressed whether fibronectin influences lens cell fate, using DCDML cells as a serum-free primary lens epithelial cell culture system. We found that culturing DCDMLs with plasma-derived fibronectin upregulated canonical TGFβ signaling relative to cells plated on laminin. Fibronectin-exposed cultures also showed increased TGFβ signaling-dependent differentiation into the two cell types responsible for posterior capsule opacification after cataract surgery, namely myofibroblasts and lens fiber cells. Increased TGFβ activity could be identified in the conditioned medium recovered from cells grown on fibronectin. Other experiments showed that plating DCDMLs on fibronectin overcomes the need for BMP in fibroblast growth factor (FGF)-induced lens fiber cell differentiation, a requirement that is restored when endogenous TGFβ signaling is inhibited. These results demonstrate how the TGFβ-fibronectin axis can profoundly affect lens cell fate. This axis represents a novel target for prevention of late-onset posterior capsule opacification, a common but currently intractable complication of cataract surgery.
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Affiliation(s)
- Judy K VanSlyke
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, Portland, OR 97239, USA
| | - Bruce A Boswell
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, Portland, OR 97239, USA
| | - Linda S Musil
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, Portland, OR 97239, USA
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Martynova E, Bouchard M, Musil LS, Cvekl A. Identification of Novel Gata3 Distal Enhancers Active in Mouse Embryonic Lens. Dev Dyn 2018; 247:1186-1198. [PMID: 30295986 PMCID: PMC6246825 DOI: 10.1002/dvdy.24677] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 09/30/2018] [Accepted: 10/01/2018] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND The tissue-specific transcriptional programs during normal development require tight control by distal cis-regulatory elements, such as enhancers, with specific DNA sequences recognized by transcription factors, coactivators, and chromatin remodeling enzymes. Gata3 is a sequence-specific DNA-binding transcription factor that regulates formation of multiple tissues and organs, including inner ear, lens, mammary gland, T-cells, urogenital system, and thyroid gland. In the eye, Gata3 has a highly restricted expression domain in the posterior part of the lens vesicle; however, the underlying regulatory mechanisms are unknown. RESULTS Here we describe the identification of a novel bipartite Gata3 lens-specific enhancer located ∼18 kb upstream from its transcriptional start site. We also found that a 5-kb Gata3 promoter possesses low activity in the lens. The bipartite enhancer contains arrays of AP-1, Ets-, and Smad1/5-binding sites as well as binding sites for lens-associated DNA-binding factors. Transient transfection studies of the promoter with the bipartite enhancer showed enhanced activation by BMP4 and FGF2. CONCLUSIONS These studies identify a novel distal enhancer of Gata3 with high activity in lens and indicate that BMP and FGF signaling can up-regulate expression of Gata3 in differentiating lens fiber cells through the identified Gata3 enhancer and promoter elements. Developmental Dynamics 247:1186-1198, 2018. © 2018 The Authors. Developmental Dynamics published by Wiley Periodicals, Inc. on behalf of American Association of Anatomists.
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Affiliation(s)
- Elena Martynova
- Departments of Ophthalmology and Visual Sciences and Genetics, Albert Einstein College of Medicine, Bronx, New York
| | - Maxime Bouchard
- Goodman Cancer Research Centre and Department of Biochemistry, McGill University, Montreal, Quebec, Canada
| | - Linda S Musil
- Department of Biochemistry and Molecular Biology, Oregon Health Science University, Portland, Oregon
| | - Ales Cvekl
- Departments of Ophthalmology and Visual Sciences and Genetics, Albert Einstein College of Medicine, Bronx, New York
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Mochizuki T, Kojima Y, Nishiwaki Y, Harakuni T, Masai I. Endocytic trafficking factor VPS45 is essential for spatial regulation of lens fiber differentiation in zebrafish. Development 2018; 145:145/20/dev170282. [PMID: 30322969 PMCID: PMC6215396 DOI: 10.1242/dev.170282] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 09/10/2018] [Indexed: 01/20/2023]
Abstract
In vertebrate lens, lens epithelial cells cover the anterior half of the lens fiber core. Lens epithelial cells proliferate, move posteriorly and start to differentiate into lens fiber cells at the lens equator. Although FGF signaling promotes this equatorial commencement of lens fiber differentiation, the underlying mechanism is not fully understood. Here, we show that lens epithelial cells abnormally enter lens fiber differentiation without passing through the equator in zebrafish vps45 mutants. VPS45 belongs to the Sec1/Munc18-like protein family and promotes endosome trafficking, which differentially modulates signal transduction. Ectopic lens fiber differentiation in vps45 mutants does not depend on FGF, but is mediated through activation of TGFβ signaling and inhibition of canonical Wnt signaling. Thus, VPS45 normally suppresses lens fiber differentiation in the anterior region of lens epithelium by modulating TGFβ and canonical Wnt signaling pathways. These data indicate a novel role of endosome trafficking to ensure equator-dependent commencement of lens fiber differentiation. Summary: The endocytic regulator VPS45 suppresses FGF-independent lens fiber differentiation and ensures the spatial pattern of lens development.
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Affiliation(s)
- Toshiaki Mochizuki
- Developmental Neurobiology Unit, Okinawa Institute of Science and Technology Graduate University, Tancha 1919-1, Onna, Okinawa 098-0945, Japan
| | - Yutaka Kojima
- Developmental Neurobiology Unit, Okinawa Institute of Science and Technology Graduate University, Tancha 1919-1, Onna, Okinawa 098-0945, Japan
| | - Yuko Nishiwaki
- Developmental Neurobiology Unit, Okinawa Institute of Science and Technology Graduate University, Tancha 1919-1, Onna, Okinawa 098-0945, Japan
| | - Tetsuya Harakuni
- Developmental Neurobiology Unit, Okinawa Institute of Science and Technology Graduate University, Tancha 1919-1, Onna, Okinawa 098-0945, Japan
| | - Ichiro Masai
- Developmental Neurobiology Unit, Okinawa Institute of Science and Technology Graduate University, Tancha 1919-1, Onna, Okinawa 098-0945, Japan
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Roles of TGF β and FGF Signals in the Lens: Tropomyosin Regulation for Posterior Capsule Opacity. Int J Mol Sci 2018; 19:ijms19103093. [PMID: 30304871 PMCID: PMC6212802 DOI: 10.3390/ijms19103093] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 10/03/2018] [Accepted: 10/04/2018] [Indexed: 01/16/2023] Open
Abstract
Transforming growth factor (TGF) β and fibroblast growth factor (FGF) 2 are related to the development of posterior capsule opacification (PCO) after lens extraction surgery and other processes of epithelial–mesenchymal transition (EMT). Oxidative stress seems to activate TGF β1 largely through reactive oxygen species (ROS) production, which in turn alters the transcription of several survival genes, including lens epithelium-cell derived growth factor (LEDGF). Higher ROS levels attenuate LEDGF function, leading to down-regulation of peroxiredoxin 6 (Prdx6). TGF β is regulated by ROS in Prdx6 knock-out lens epithelial cells (LECs) and induces the up-regulation of tropomyosins (Tpms) 1/2, and EMT of LECs. Mouse and rat PCO are accompanied by elevated expression of Tpm2. Further, the expression of Tpm1/2 is induced by TGF β2 in LECs. Importantly, we previously showed that TGF β2 and FGF2 play regulatory roles in LECs in a contrasting manner. An injury-induced EMT of a mouse lens as a PCO model was attenuated in the absence of Tpm2. In this review, we present findings regarding the roles of TGF β and FGF2 in the differential regulation of EMT in the lens. Tpms may be associated with TGF β2- and FGF2-related EMT and PCO development.
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Spred negatively regulates lens growth by modulating epithelial cell proliferation and fiber differentiation. Exp Eye Res 2018; 178:160-175. [PMID: 30290165 DOI: 10.1016/j.exer.2018.09.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Revised: 08/28/2018] [Accepted: 09/28/2018] [Indexed: 12/27/2022]
Abstract
Spred, like Sprouty (Spry) and also Sef proteins, have been identified as important regulators of receptor tyrosine kinase (RTK)-mediated MAPK/ERK-signaling in various developmental systems, controlling cellular processes such as proliferation, migration and differentiation. Spreds are widely expressed during early embryogenesis, and in the eye lens, become more localised in the lens epithelium with later development, overlapping with other antagonists including Spry. Given the synexpression of Spreds and Spry in lens, in order to gain a better understanding of their specific roles in regulating growth factor mediated-signaling and cell behavior, we established and characterised lines of transgenic mice overexpressing Spred1 or Spred2, specifically in the lens. This overexpression of Spreds resulted in a small lens phenotype during ocular morphogenesis, retarding its growth by compromising epithelial cell proliferation and fiber differentiation. These in situ findings were shown to be dependent on the ability of Spreds to suppress MAPK-signaling, in particular FGF-induced ERK1/2-signaling in lens cells. This was validated in vitro using lens epithelial explants, that highlighted the overlapping role of Spreds with Spry2, but not Spry1. This study provides insights into the putative function of Spreds and Spry in situ, some overlapping and some distinct, and their importance in regulating lens cell proliferation and fiber differentiation contributing to lens and eye growth.
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Zhao G, Bailey CG, Feng Y, Rasko J, Lovicu FJ. Negative regulation of lens fiber cell differentiation by RTK antagonists Spry and Spred. Exp Eye Res 2018; 170:148-159. [PMID: 29501879 PMCID: PMC5924633 DOI: 10.1016/j.exer.2018.02.025] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 02/09/2018] [Accepted: 02/25/2018] [Indexed: 11/19/2022]
Abstract
Sprouty (Spry) and Spred proteins have been identified as closely related negative regulators of the receptor tyrosine kinase (RTK)-mediated MAPK pathway, inhibiting cellular proliferation, migration and differentiation in many systems. As the different members of this antagonist family are strongly expressed in the lens epithelium in overlapping patterns, in this study we used lens epithelial explants to examine the impact of these different antagonists on the morphologic and molecular changes associated with fibroblast growth factor (FGF)-induced lens fiber differentiation. Cells in lens epithelial explants were transfected using different approaches to overexpress the different Spry (Spry1, Spry2) and Spred (Spred1, Spred2, Spred3) members, and we compared their ability to undergo FGF-induced fiber differentiation. In cells overexpressing any of the antagonists, the propensity for FGF-induced cell elongation was significantly reduced, indicative of a block to lens fiber differentiation. Of these antagonists, Spry1 and Spred2 appeared to be the most potent among their respective family members, demonstrating the greatest block in FGF-induced fiber differentiation based on the percentage of cells that failed to elongate. Consistent with the reported activity of Spry and Spred, we show that overexpression of Spry2 was able to suppress FGF-induced ERK1/2 phosphorylation in lens cells, as well as the ERK1/2-dependent fiber-specific marker Prox1, but not the accumulation of β-crystallins. Taken together, Spry and Spred proteins that are predominantly expressed in the lens epithelium in situ, appear to have overlapping effects on negatively regulating ERK1/2-signaling associated with FGF-induced lens epithelial cell elongation leading to fiber differentiation. This highlights the important regulatory role for these RTK antagonists in establishing and maintaining the distinct architecture and polarity of the lens.
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Affiliation(s)
- Guannan Zhao
- Discipline of Anatomy and Histology, Bosch Institute, University of Sydney, NSW, Australia
| | - Charles G Bailey
- Gene & Stem Cell Therapy Program, Centenary Institute, Camperdown, NSW, Australia; Sydney Medical School, University of Sydney, NSW, Australia
| | - Yue Feng
- Gene & Stem Cell Therapy Program, Centenary Institute, Camperdown, NSW, Australia
| | - John Rasko
- Gene & Stem Cell Therapy Program, Centenary Institute, Camperdown, NSW, Australia; Sydney Medical School, University of Sydney, NSW, Australia; Department of Cell & Molecular Therapies, Royal Prince Alfred Hospital, Camperdown, NSW, Australia
| | - Frank J Lovicu
- Discipline of Anatomy and Histology, Bosch Institute, University of Sydney, NSW, Australia; Save Sight Institute, University of Sydney, NSW, Australia.
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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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41
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Abstract
The eye lens grows by systematic proliferation of its epithelial cells and their differentiation into fibre cells. The anterior aqueous humour regulates lens epithelial cell proliferation whereas posteriorly, the vitreous stimulates lens fibre differentiation. Vitreous-derived members of the fibroblast growth factor (FGF) family induce fibre differentiation, with added support for FGFs as putative regulators of aqueous-induced lens cell proliferation. To further characterize this, given FGFs' known affinity for proteoglycans, we compared the effect of proteoglycan sulphation in growth factor- and aqueous-induced lens cell proliferation. Disruption of proteoglycan sulphation in lens cells specifically impacted on aqueous- and FGF-induced MAPK/ERK1/2-signalling, but not on that induced by other mitogens such as PDGF; however, cell proliferation was reduced in all treatment groups, regardless of the mitogen. Overall, by disrupting proteoglycan activity, we further highlight the significant role of FGFs in aqueous-induced ERK1/2 phosphorylation leading to lens cell proliferation.
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Affiliation(s)
- Laxmi Iyengar
- a Save Sight Institute and Discipline of Anatomy and Histology, Bosch Institute, University of Sydney , Sydney , Australia
| | - Frank J Lovicu
- a Save Sight Institute and Discipline of Anatomy and Histology, Bosch Institute, University of Sydney , Sydney , Australia
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42
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Cvekl A, Zhang X. Signaling and Gene Regulatory Networks in Mammalian Lens Development. Trends Genet 2017; 33:677-702. [PMID: 28867048 DOI: 10.1016/j.tig.2017.08.001] [Citation(s) in RCA: 120] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 07/27/2017] [Accepted: 08/01/2017] [Indexed: 11/16/2022]
Abstract
Ocular lens development represents an advantageous system in which to study regulatory mechanisms governing cell fate decisions, extracellular signaling, cell and tissue organization, and the underlying gene regulatory networks. Spatiotemporally regulated domains of BMP, FGF, and other signaling molecules in late gastrula-early neurula stage embryos generate the border region between the neural plate and non-neural ectoderm from which multiple cell types, including lens progenitor cells, emerge and undergo initial tissue formation. Extracellular signaling and DNA-binding transcription factors govern lens and optic cup morphogenesis. Pax6, c-Maf, Hsf4, Prox1, Sox1, and a few additional factors regulate the expression of the lens structural proteins, the crystallins. Extensive crosstalk between a diverse array of signaling pathways controls the complexity and order of lens morphogenetic processes and lens transparency.
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Affiliation(s)
- Ales Cvekl
- Departments of Genetics and Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
| | - Xin Zhang
- Departments of Ophthalmology, Pathology and Cell Biology, Columbia University Medical Center, New York, NY 10032, USA.
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43
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Cao L, Liu J, Pu J, Collinson JM, Forrester JV, McCaig CD. Endogenous bioelectric currents promote differentiation of the mammalian lens. J Cell Physiol 2017; 233:2202-2212. [PMID: 28661005 PMCID: PMC5724684 DOI: 10.1002/jcp.26074] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 06/28/2017] [Indexed: 12/18/2022]
Abstract
The functional roles of bioelectrical signals (ES) created by the flow of specific ions at the mammalian lens equator are poorly understood. We detected that mature, denucleated lens fibers expressed high levels of the α1 and β1 subunits of Na+/K+‐ATPase (ATP1A1 and ATP1B1 of the sodium pump) and had a hyperpolarized membrane potential difference (Vmem). In contrast, differentiating, nucleated lens fiber cells had little ATP1A1 and ATP1B1 and a depolarized Vmem. Mimicking the natural equatorial ES with an applied electrical field (EF) induced a striking reorientation of lens epithelial cells to lie perpendicular to the direction of the EF. An EF also promoted the expression of β‐crystallin, aquaporin‐0 (AQP0) and the Beaded Filament Structural Protein 2 (BFSP2) in lens epithelial cells (LECs), all of which are hallmarks of differentiation. In addition, applied EF activated the AKT and CDC2 and inhibition of AKT reduced the activation of CDC2. Our results indicate that the endogenous bioelectrical signal at the lens equator promotes differentiation of LECs into denucleated lens fiber cells via depolarization of Vmem. Development of methods and devices of EF application or amplification in vivo may supply a novel treatment for lens diseases and even promote regeneration of a complete new lens following cataract surgery.
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Affiliation(s)
- Lin Cao
- Institute of Medical Sciences, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | - Jie Liu
- Department of Ophthalmology, First Hospital Affiliated to the Chinese PLA General Hospital, Beijing, P.R. China
| | - Jin Pu
- Institute of Medical Sciences, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | - J Martin Collinson
- Institute of Medical Sciences, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | - John V Forrester
- Institute of Medical Sciences, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | - Colin D McCaig
- Institute of Medical Sciences, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
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44
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Hahn C, Genner MJ, Turner GF, Joyce DA. The genomic basis of cichlid fish adaptation within the deepwater "twilight zone" of Lake Malawi. Evol Lett 2017; 1:184-198. [PMID: 30283648 PMCID: PMC6124600 DOI: 10.1002/evl3.20] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Revised: 06/01/2017] [Accepted: 07/11/2017] [Indexed: 12/21/2022] Open
Abstract
Deepwater environments are characterized by low levels of available light at narrow spectra, great hydrostatic pressure, and low levels of dissolved oxygen—conditions predicted to exert highly specific selection pressures. In Lake Malawi over 800 cichlid species have evolved, and this adaptive radiation extends into the “twilight zone” below 50 m. We use population‐level RAD‐seq data to investigate whether four endemic deepwater species (Diplotaxodon spp.) have experienced divergent selection within this environment. We identify candidate genes including regulators of photoreceptor function, photopigments, lens morphology, and haemoglobin, many not previously implicated in cichlid adaptive radiations. Colocalization of functionally linked genes suggests coadapted “supergene” complexes. Comparisons of Diplotaxodon to the broader Lake Malawi radiation using genome resequencing data revealed functional substitutions and signatures of positive selection in candidate genes. Our data provide unique insights into genomic adaptation within deepwater habitats, and suggest genome‐level specialization for life at depth as an important process in cichlid radiation.
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Affiliation(s)
- Christoph Hahn
- Evolutionary and Environmental Genomics Group (@EvoHull), School of Environmental Sciences University of Hull Hull HU5 7RX United Kingdom.,Institute of Zoology University of Graz A-8010 Graz Austria
| | - Martin J Genner
- School of Biological Sciences University of Bristol Bristol Life Sciences Building, 24 Tyndall Avenue Bristol BS8 1TQ United Kingdom
| | - George F Turner
- School of Biological Sciences Bangor University Bangor Gwynedd LL57 2UW Wales United Kingdom
| | - Domino A Joyce
- Evolutionary and Environmental Genomics Group (@EvoHull), School of Environmental Sciences University of Hull Hull HU5 7RX United Kingdom
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45
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Cavalheiro GR, Matos-Rodrigues GE, Zhao Y, Gomes AL, Anand D, Predes D, de Lima S, Abreu JG, Zheng D, Lachke SA, Cvekl A, Martins RAP. N-myc regulates growth and fiber cell differentiation in lens development. Dev Biol 2017; 429:105-117. [PMID: 28716713 DOI: 10.1016/j.ydbio.2017.07.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Revised: 06/07/2017] [Accepted: 07/05/2017] [Indexed: 11/26/2022]
Abstract
Myc proto-oncogenes regulate diverse cellular processes during development, but their roles during morphogenesis of specific tissues are not fully understood. We found that c-myc regulates cell proliferation in mouse lens development and previous genome-wide studies suggested functional roles for N-myc in developing lens. Here, we examined the role of N-myc in mouse lens development. Genetic inactivation of N-myc in the surface ectoderm or lens vesicle impaired eye and lens growth, while "late" inactivation in lens fibers had no effect. Unexpectedly, defective growth of N-myc-deficient lenses was not associated with alterations in lens progenitor cell proliferation or survival. Notably, N-myc-deficient lens exhibited a delay in degradation of DNA in terminally differentiating lens fiber cells. RNA-sequencing analysis of N-myc-deficient lenses identified a cohort of down-regulated genes associated with fiber cell differentiation that included DNaseIIβ. Further, an integrated analysis of differentially expressed genes in N-myc-deficient lens using normal lens expression patterns of iSyTE, N-myc-binding motif analysis and molecular interaction data from the String database led to the derivation of an N-myc-based gene regulatory network in the lens. Finally, analysis of N-myc and c-myc double-deficient lens demonstrated that these Myc genes cooperate to drive lens growth prior to lens vesicle stage. Together, these findings provide evidence for exclusive and cooperative functions of Myc transcription factors in mouse lens development and identify novel mechanisms by which N-myc regulates cell differentiation during eye morphogenesis.
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Affiliation(s)
- Gabriel R Cavalheiro
- Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Gabriel E Matos-Rodrigues
- Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Yilin Zhao
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Anielle L Gomes
- Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Deepti Anand
- Department of Biological Sciences, University of Delaware, Newark, DE, USA
| | - Danilo Predes
- Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Silmara de Lima
- Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Jose G Abreu
- Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Deyou Zheng
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY, USA; Department of Neurology, Albert Einstein College of Medicine, Bronx, NY, USA; Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Salil A Lachke
- Department of Biological Sciences, University of Delaware, Newark, DE, USA; Center for Bioinformatics and Computational Biology, University of Delaware, Newark, DE, USA
| | - Ales Cvekl
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY, USA; Department of Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Rodrigo A P Martins
- Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
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46
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Bassnett S, Šikić H. The lens growth process. Prog Retin Eye Res 2017; 60:181-200. [PMID: 28411123 DOI: 10.1016/j.preteyeres.2017.04.001] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Revised: 04/06/2017] [Accepted: 04/10/2017] [Indexed: 01/17/2023]
Abstract
The factors that regulate the size of organs to ensure that they fit within an organism are not well understood. A simple organ, the ocular lens serves as a useful model with which to tackle this problem. In many systems, considerable variance in the organ growth process is tolerable. This is almost certainly not the case in the lens, which in addition to fitting comfortably within the eyeball, must also be of the correct size and shape to focus light sharply onto the retina. Furthermore, the lens does not perform its optical function in isolation. Its growth, which continues throughout life, must therefore be coordinated with that of other tissues in the optical train. Here, we review the lens growth process in detail, from pioneering clinical investigations in the late nineteenth century to insights gleaned more recently in the course of cell and molecular studies. During embryonic development, the lens forms from an invagination of surface ectoderm. Consequently, the progenitor cell population is located at its surface and differentiated cells are confined to the interior. The interactions that regulate cell fate thus occur within the obligate ellipsoidal geometry of the lens. In this context, mathematical models are particularly appropriate tools with which to examine the growth process. In addition to identifying key growth determinants, such models constitute a framework for integrating cell biological and optical data, helping clarify the relationship between gene expression in the lens and image quality at the retinal plane.
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Affiliation(s)
- Steven Bassnett
- Department of Ophthalmology & Visual Sciences, Washington University School of Medicine, USA.
| | - Hrvoje Šikić
- Department of Mathematics, Faculty of Science, University of Zagreb, Croatia
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Boswell BA, Korol A, West-Mays JA, Musil LS. Dual function of TGFβ in lens epithelial cell fate: implications for secondary cataract. Mol Biol Cell 2017; 28:907-921. [PMID: 28209733 PMCID: PMC5385940 DOI: 10.1091/mbc.e16-12-0865] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 02/06/2017] [Accepted: 02/07/2017] [Indexed: 12/29/2022] Open
Abstract
The most common vision-disrupting complication of cataract surgery is posterior capsule opacification (PCO; secondary cataract). PCO is caused by residual lens cells undergoing one of two very different cell fates: either transdifferentiating into myofibroblasts or maturing into lens fiber cells. Although TGFβ has been strongly implicated in lens cell fibrosis, the factors responsible for the latter process have not been identified. We show here for the first time that TGFβ can induce purified primary lens epithelial cells within the same culture to undergo differentiation into either lens fiber cells or myofibroblasts. Marker analysis confirmed that the two cell phenotypes were mutually exclusive. Blocking the p38 kinase pathway, either with direct inhibitors of the p38 MAP kinase or a small-molecule therapeutic that also inhibits the activation of p38, prevented TGFβ from inducing epithelial-myofibroblast transition and cell migration but did not prevent fiber cell differentiation. Rapamycin had the converse effect, linking MTOR signaling to induction of fiber cell differentiation by TGFβ. In addition to providing novel potential therapeutic strategies for PCO, our findings extend the so-called TGFβ paradox, in which TGFβ can induce two disparate cell fates, to a new epithelial disease state.
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Affiliation(s)
- Bruce A Boswell
- Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, OR 97239
| | - Anna Korol
- Department of Pathology and Molecular Medicine, McMaster University Health Science Centre, Hamilton, ON L8N 3Z5, Canada
| | - Judith A West-Mays
- Department of Pathology and Molecular Medicine, McMaster University Health Science Centre, Hamilton, ON L8N 3Z5, Canada
| | - Linda S Musil
- Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, OR 97239
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Kubo E, Shibata S, Shibata T, Kiyokawa E, Sasaki H, Singh DP. FGF2 antagonizes aberrant TGFβ regulation of tropomyosin: role for posterior capsule opacity. J Cell Mol Med 2016; 21:916-928. [PMID: 27976512 PMCID: PMC5387175 DOI: 10.1111/jcmm.13030] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Accepted: 10/10/2016] [Indexed: 12/21/2022] Open
Abstract
Transforming growth factor (TGF) β2 and fibroblast growth factor (FGF) 2 are involved in regulation of posterior capsule opacification (PCO) and other processes of epithelial–mesenchymal transition (EMT) such as cancer progression, wound healing and tissue fibrosis as well as normal embryonic development. We previously used an in vivo rodent PCO model to show the expression of tropomyosin (Tpm) 1/2 was aberrantly up‐regulated in remodelling the actin cytoskeleton during EMT. In this in vitro study, we show the Tpms family of cytoskeleton proteins are involved in regulating and stabilizing actin microfilaments (F‐actin) and are induced by TGFβ2 during EMT in lens epithelial cells (LECs). Importantly, we found TGFβ2 and FGF2 played contrasting roles. Stress fibre formation and up‐regulation of α‐smooth muscle actin (αSMA) induced by TGFβ2 could be reversed by Tpm1/2 knock‐down by siRNA. Expression of Tpm1/2 and stress fibre formation induced by TGFβ2 could be reversed by FGF2. Furthermore, FGF2 delivery to TGFβ‐treated LECs perturbed EMT by reactivating the mitogen‐activated protein kinase (MAPK)/ extracellular signal‐regulated kinase (ERK) pathway and subsequently enhanced EMT. Conversely, MEK inhibitor (PD98059) abated the FGF2‐mediated Tpm1/2 and αSMA suppression. However, we found that normal LECs which underwent EMT showed enhanced migration in response to combined TGFβ and FGF2 stimulation. These findings may help clarify the mechanism reprogramming the actin cytoskeleton during morphogenetic EMT cell proliferation and fibre regeneration in PCO. We propose that understanding the physiological link between levels of FGF2, Tpm1/2 expression and TGFβs‐driven EMT orchestration may provide clue(s) to develop therapeutic strategies to treat PCO based on Tpm1/2.
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Affiliation(s)
- Eri Kubo
- Department of Ophthalmology, Kanazawa Medical University, Uchinada, Kahoku-gun, Ishikawa, Japan
| | - Shinsuke Shibata
- Department of Ophthalmology, Kanazawa Medical University, Uchinada, Kahoku-gun, Ishikawa, Japan
| | - Teppei Shibata
- Department of Ophthalmology, Kanazawa Medical University, Uchinada, Kahoku-gun, Ishikawa, Japan
| | - Etsuko Kiyokawa
- Department of Oncogenic Pathology, Kanazawa Medical University, Uchinada, Kahoku-gun, Ishikawa, Japan
| | - Hiroshi Sasaki
- Department of Ophthalmology, Kanazawa Medical University, Uchinada, Kahoku-gun, Ishikawa, Japan
| | - Dhirendra P Singh
- Department of Ophthalmology and Visual Sciences, University of Nebraska Medical Center, Omaha, NE, USA
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Thein T, de Melo J, Zibetti C, Clark BS, Juarez F, Blackshaw S. Control of lens development by Lhx2-regulated neuroretinal FGFs. Development 2016; 143:3994-4002. [PMID: 27633990 PMCID: PMC5117141 DOI: 10.1242/dev.137760] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 09/01/2016] [Indexed: 01/07/2023]
Abstract
Fibroblast growth factor (FGF) signaling is an essential regulator of lens epithelial cell proliferation and survival, as well as lens fiber cell differentiation. However, the identities of these FGF factors, their source tissue and the genes that regulate their synthesis are unknown. We have found that Chx10-Cre;Lhx2lox/lox mice, which selectively lack Lhx2 expression in neuroretina from E10.5, showed an early arrest in lens fiber development along with severe microphthalmia. These mutant animals showed reduced expression of multiple neuroretina-expressed FGFs and canonical FGF-regulated genes in neuroretina. When FGF expression was genetically restored in Lhx2-deficient neuroretina of Chx10-Cre;Lhx2lox/lox mice, we observed a partial but nonetheless substantial rescue of the defects in lens cell proliferation, survival and fiber differentiation. These data demonstrate that neuroretinal expression of Lhx2 and neuroretina-derived FGF factors are crucial for lens fiber development in vivo.
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Affiliation(s)
- Thuzar Thein
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
| | - Jimmy de Melo
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
| | - Cristina Zibetti
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
| | - Brian S Clark
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
| | - Felicia Juarez
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
| | - Seth Blackshaw
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
- Department of Ophthalmology, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
- Center for Human Systems Biology, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
- Institute for Cell Engineering, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
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Pathania M, Wang Y, Simirskii VN, Duncan MK. β1-integrin controls cell fate specification in early lens development. Differentiation 2016; 92:133-147. [PMID: 27596755 PMCID: PMC5159248 DOI: 10.1016/j.diff.2016.08.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 07/05/2016] [Accepted: 08/09/2016] [Indexed: 02/03/2023]
Abstract
Integrins are heterodimeric cell surface molecules that mediate cell-extracellular matrix (ECM) adhesion, ECM assembly, and regulation of both ECM and growth factor induced signaling. However, the developmental context of these diverse functions is not clear. Loss of β1-integrin from the lens vesicle (mouse E10.5) results in abnormal exit of anterior lens epithelial cells (LECs) from the cell cycle and their aberrant elongation toward the presumptive cornea by E12.5. These cells lose expression of LEC markers and initiate expression of the Maf (also known as c-Maf) and Prox1 transcription factors as well as other lens fiber cell markers. β1-integrin null LECs also upregulate the ERK, AKT and Smad1/5/8 phosphorylation indicative of BMP and FGF signaling. By E14.5, β1-integrin null lenses have undergone a complete conversion of all lens epithelial cells into fiber cells. These data suggest that shortly after lens vesicle closure, β1-integrin blocks inappropriate differentiation of the lens epithelium into fibers, potentially by inhibiting BMP and/or FGF receptor activation. Thus, β1-integrin has an important role in fine-tuning the response of the early lens to the gradient of growth factors that regulate lens fiber cell differentiation.
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Affiliation(s)
- Mallika Pathania
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - Yan Wang
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - Vladimir N Simirskii
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - Melinda K Duncan
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA.
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