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Xu W, Sun Y, Zhao S, Zhao J, Zhang J. Identification and validation of autophagy-related genes in primary open-angle glaucoma. BMC Med Genomics 2023; 16:287. [PMID: 37968618 PMCID: PMC10648356 DOI: 10.1186/s12920-023-01722-5] [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: 04/24/2023] [Accepted: 10/31/2023] [Indexed: 11/17/2023] Open
Abstract
BACKGROUND As the most common type of glaucoma, the etiology of primary open-angle glaucoma (POAG) has not been unified. Autophagy may affect the occurrence and development of POAG, while the specific mechanism and target need to be further explored. METHODS The GSE27276 dataset from the Gene Expression Omnibus (GEO) database and the autophagy gene set from the GeneCards database were selected to screen differentially expressed autophagy-related genes (DEARGs) of POAG. Hub DEARGs were selected by constructing protein-protein interaction (PPI) networks and utilizing GSE138125 dataset. Subsequently, immune cell infiltration analysis, genome-wide association study (GWAS) analysis, gene set enrichment analysis (GSEA) and other analyses were performed on the hub genes. Eventually, animal experiments were performed to verify the mRNA levels of the hub genes by quantitative real time polymerase chain reaction (qRT-PCR). RESULTS A total of 67 DEARGs and 2 hub DEARGs, HSPA8 and RPL15, were selected. The hub genes were closely related to the level of immune cell infiltration. GWAS analysis confirmed that the causative regions of the 2 hub genes in glaucoma were on chromosome 11 and chromosome 3, respectively. GSEA illustrated that pathways enriched for highly expressed HSPA8 and RPL15 contained immunity, autophagy, gene expression and energy metabolism-related pathways. qRT-PCR confirmed that the expression of Hspa8 and Rpl15 in the rat POAG model was consistent with the results of bioinformatics analysis. CONCLUSIONS This study indicated that HSPA8 and RPL15 may affect the progression of POAG by regulating autophagy and provided new ideas for the pathogenesis and treatment of POAG.
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Affiliation(s)
- Wanjing Xu
- Ophthalmology Department of QingPu Branch of Zhongshan Hospital Affiliated to Fudan University, Shanghai, China.
| | - Yuhao Sun
- Otolaryngology Department of QingPu Branch of Zhongshan Hospital Affiliated to Fudan University, Shanghai, China
| | - Shuang Zhao
- Graduate School of Shandong First Medical University, Jinan, China
| | - Jun Zhao
- Ophthalmology Department of Linyi People's Hospital, Linyi, China
| | - Juanmei Zhang
- Ophthalmology Department of Linyi People's Hospital, Linyi, China
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Van de Sompele S, Small KW, Cicekdal MB, Soriano VL, D'haene E, Shaya FS, Agemy S, Van der Snickt T, Rey AD, Rosseel T, Van Heetvelde M, Vergult S, Balikova I, Bergen AA, Boon CJF, De Zaeytijd J, Inglehearn CF, Kousal B, Leroy BP, Rivolta C, Vaclavik V, van den Ende J, van Schooneveld MJ, Gómez-Skarmeta JL, Tena JJ, Martinez-Morales JR, Liskova P, Vleminckx K, De Baere E. Multi-omics approach dissects cis-regulatory mechanisms underlying North Carolina macular dystrophy, a retinal enhanceropathy. Am J Hum Genet 2022; 109:2029-2048. [PMID: 36243009 PMCID: PMC9674966 DOI: 10.1016/j.ajhg.2022.09.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Accepted: 09/28/2022] [Indexed: 01/26/2023] Open
Abstract
North Carolina macular dystrophy (NCMD) is a rare autosomal-dominant disease affecting macular development. The disease is caused by non-coding single-nucleotide variants (SNVs) in two hotspot regions near PRDM13 and by duplications in two distinct chromosomal loci, overlapping DNase I hypersensitive sites near either PRDM13 or IRX1. To unravel the mechanisms by which these variants cause disease, we first established a genome-wide multi-omics retinal database, RegRet. Integration of UMI-4C profiles we generated on adult human retina then allowed fine-mapping of the interactions of the PRDM13 and IRX1 promoters and the identification of eighteen candidate cis-regulatory elements (cCREs), the activity of which was investigated by luciferase and Xenopus enhancer assays. Next, luciferase assays showed that the non-coding SNVs located in the two hotspot regions of PRDM13 affect cCRE activity, including two NCMD-associated non-coding SNVs that we identified herein. Interestingly, the cCRE containing one of these SNVs was shown to interact with the PRDM13 promoter, demonstrated in vivo activity in Xenopus, and is active at the developmental stage when progenitor cells of the central retina exit mitosis, suggesting that this region is a PRDM13 enhancer. Finally, mining of single-cell transcriptional data of embryonic and adult retina revealed the highest expression of PRDM13 and IRX1 when amacrine cells start to synapse with retinal ganglion cells, supporting the hypothesis that altered PRDM13 or IRX1 expression impairs interactions between these cells during retinogenesis. Overall, this study provides insight into the cis-regulatory mechanisms of NCMD and supports that this condition is a retinal enhanceropathy.
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Affiliation(s)
- Stijn Van de Sompele
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium; Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium
| | - Kent W Small
- Macula and Retina Institute, Los Angeles and Glendale, California, USA
| | - Munevver Burcu Cicekdal
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium; Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium; Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Víctor López Soriano
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium; Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium
| | - Eva D'haene
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium; Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium
| | - Fadi S Shaya
- Macula and Retina Institute, Los Angeles and Glendale, California, USA
| | - Steven Agemy
- Department of Ophthalmology, SUNY Downstate Medical Center University, Brooklyn, New York, USA
| | - Thijs Van der Snickt
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium; Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium
| | - Alfredo Dueñas Rey
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium; Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium
| | - Toon Rosseel
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium; Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium
| | - Mattias Van Heetvelde
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium; Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium
| | - Sarah Vergult
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium; Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium
| | - Irina Balikova
- Department of Ophthalmology, University Hospitals Leuven, Leuven, Belgium
| | - Arthur A Bergen
- Department of Human Genetics, Amsterdam UMC, Academic Medical Center, 1105 AZ Amsterdam, The Netherlands; Queen Emma Centre of Precision Medicine, Amsterdam University Medical Centre, University of Amsterdam, Amsterdam, The Netherlands
| | - Camiel J F Boon
- Department of Ophthalmology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands; Department of Ophthalmology, Leiden University Medical Center, Leiden, The Netherlands
| | - Julie De Zaeytijd
- Department of Ophthalmology, Ghent University Hospital, Ghent, Belgium
| | - Chris F Inglehearn
- Division of Molecular Medicine, Leeds Institute of Medical Research, University of Leeds, Leeds, UK
| | - Bohdan Kousal
- Department of Ophthalmology, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czech Republic
| | - Bart P Leroy
- Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium; Department of Ophthalmology, Ghent University Hospital, Ghent, Belgium; Department of Head & Skin, Ghent University, Ghent, Belgium; Division of Ophthalmology & Center for Cellular & Molecular Therapeutics, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Carlo Rivolta
- Institute of Molecular and Clinical Ophthalmology Basel (IOB), Basel, Switzerland; Department of Ophthalmology, University of Basel, Basel, Switzerland; Department of Genetics and Genome Biology, University of Leicester, Leicester, UK
| | - Veronika Vaclavik
- University of Lausanne, Jules-Gonin Eye Hospital, Lausanne, Switzerland
| | | | - Mary J van Schooneveld
- Department of Ophthalmology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands; Bartiméus, Diagnostic Center for Complex Visual Disorders, Zeist, The Netherlands
| | - José Luis Gómez-Skarmeta
- Centro Andaluz de Biología del Desarrollo, Consejo Superior de Investigaciones Científicas and Universidad Pablo de Olavide, Sevilla, Spain
| | - Juan J Tena
- Centro Andaluz de Biología del Desarrollo, Consejo Superior de Investigaciones Científicas and Universidad Pablo de Olavide, Sevilla, Spain
| | - Juan R Martinez-Morales
- Centro Andaluz de Biología del Desarrollo, Consejo Superior de Investigaciones Científicas and Universidad Pablo de Olavide, Sevilla, Spain
| | - Petra Liskova
- Department of Ophthalmology, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czech Republic; Department of Paediatrics and Inherited Metabolic Disorders, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czech Republic
| | - Kris Vleminckx
- Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium; Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Elfride De Baere
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium; Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium.
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3
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Liang H, Zhang F, Wang W, Zhao W, Zhou J, Feng Y, Wu J, Li M, Bai X, Zeng Z, Niu J, Miao Y. Heat Shock Transcription Factor 2 Promotes Mitophagy of Intestinal Epithelial Cells Through PARL/PINK1/Parkin Pathway in Ulcerative Colitis. Front Pharmacol 2022; 13:893426. [PMID: 35860016 PMCID: PMC9289131 DOI: 10.3389/fphar.2022.893426] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Accepted: 06/16/2022] [Indexed: 12/12/2022] Open
Abstract
The overactivation of NLRP3 inflammasome in intestinal epithelial cells (IECs) is among the important reasons for severe inflammation in ulcerative colitis (UC). We found that heat shock transcription factor 2 (HSF2), which is highly expressed in UC, could inhibit the activation of NLRP3 inflammasome and reduce IL-1β in IECs, but the mechanisms were still not clear. It has been reported that HSP72 regulated by HSF2 can enhance the mitophagy mediated by Parkin. The number of damaged mitochondria and the mitochondrial derived ROS (mtROS) can be reduced by mitophagy, which means the activity of NLRP3 inflammasome is inhibited. Therefore, we speculate that HSF2 might regulate the activation of NLRP3 inflammasome of IECs in UC through the mitophagy mediated by Parkin. This study proves that the number of damaged mitochondria in IECs, the level of mitophagy, and the level of ROS in intestinal mucosa are positively correlated with the severity of UC. In mice and cells, mitophagy was promoted by HSF2 through the PARL/PINK1/Parkin pathway. This study reveals the potential mechanisms of HSF2 decreasing mtROS of IECs in UC.
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Affiliation(s)
- Hao Liang
- Kunming Medical University, Kunming, China
- Department of Gastroenterology, The First Affiliated Hospital of Kunming Medical University, Kunming, China
- Yunnan Province Clinical Research Center for Digestive Diseases, Kunming, China
| | - Fengrui Zhang
- Department of Gastroenterology, The First Affiliated Hospital of Kunming Medical University, Kunming, China
- Yunnan Province Clinical Research Center for Digestive Diseases, Kunming, China
| | - Wen Wang
- Department of Gastroenterology, The First Affiliated Hospital of Kunming Medical University, Kunming, China
- Yunnan Province Clinical Research Center for Digestive Diseases, Kunming, China
| | - Wei Zhao
- Kunming Medical University, Kunming, China
| | - Jiao Zhou
- Kunming Medical University, Kunming, China
| | - Yuran Feng
- Department of Ultrasound, First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Jing Wu
- Department of Gastroenterology, The First Affiliated Hospital of Kunming Medical University, Kunming, China
- Yunnan Province Clinical Research Center for Digestive Diseases, Kunming, China
| | - Maojuan Li
- Department of Gastroenterology, The First Affiliated Hospital of Kunming Medical University, Kunming, China
- Yunnan Province Clinical Research Center for Digestive Diseases, Kunming, China
| | - Xinyu Bai
- Kunming Medical University, Kunming, China
- Department of Gastroenterology, The First Affiliated Hospital of Kunming Medical University, Kunming, China
- Yunnan Province Clinical Research Center for Digestive Diseases, Kunming, China
| | - Zhong Zeng
- Yunnan Province Clinical Research Center for Digestive Diseases, Kunming, China
- Organ Transplantation Center, The First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Junkun Niu
- Department of Gastroenterology, The First Affiliated Hospital of Kunming Medical University, Kunming, China
- Yunnan Province Clinical Research Center for Digestive Diseases, Kunming, China
- *Correspondence: Junkun Niu, ; Yinglei Miao,
| | - Yinglei Miao
- Department of Gastroenterology, The First Affiliated Hospital of Kunming Medical University, Kunming, China
- Yunnan Province Clinical Research Center for Digestive Diseases, Kunming, China
- *Correspondence: Junkun Niu, ; Yinglei Miao,
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Thioredoxins 1 and 2 protect retinal ganglion cells from pharmacologically induced oxidative stress, optic nerve transection and ocular hypertension. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2011; 664:355-63. [PMID: 20238036 DOI: 10.1007/978-1-4419-1399-9_41] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
Abstract
Oxidative damage has been implicated in retinal ganglion cell (RGC) death after optic nerve transection (ONT) and during glaucomatous neuropathy. Here, we analyzed the expression and cell protective role of thioredoxins (TRX), key regulators of the cellular redox state, in RGCs damaged by pharmacologically induced oxidative stress, ONT and elevated intraocular pressure (IOP). The endogenous level of thioredoxin-1 (TRX1) and thioredoxin-2 (TRX2) in RGCs after axotomy and in RGC-5 cells after glutamate/buthionine sulfoximine (BSO) treatment showed upregulation of TRX2, whereas no significant change was observed in TRX1 expression. The increased level TRX-interacting protein (TXNIP) in the retinas was observed 2 and 5 weeks after IOP elevation. TRX1 level was decreased at 2 weeks and more prominently at 5 weeks after IOP increase. No change in TRX2 levels in response to IOP change was observed. Overexpression of TRX1 and TRX2 in RGC-5 treated with glutamate/BSO increased the cell survival by 2- and 3-fold 24 and 48 h after treatment, respectively. Overexpression of these proteins in the retina increased the survival of RGCs by 35 and 135% 7 and 14 days after ONT, respectively. In hypertensive eyes, RGC loss was approximately 27% 5 weeks after IOP elevation compared to control. TRX1 and TRX2 overexpression preserved approximately 45 and 37% of RGCs, respectively, that were destined to die due to IOP increase.
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5
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Tucker NR, Middleton RC, Le QP, Shelden EA. HSF1 is essential for the resistance of zebrafish eye and brain tissues to hypoxia/reperfusion injury. PLoS One 2011; 6:e22268. [PMID: 21814572 PMCID: PMC3141033 DOI: 10.1371/journal.pone.0022268] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2011] [Accepted: 06/21/2011] [Indexed: 12/21/2022] Open
Abstract
Ischemia and subsequent reperfusion (IR) produces injury to brain, eye and other tissues, contributing to the progression of important clinical pathologies. The response of cells to IR involves activation of several signaling pathways including those activating hypoxia and heat shock responsive transcription factors. However, specific roles of these responses in limiting cell damage and preventing cell death after IR have not been fully elucidated. Here, we have examined the role of heat shock factor 1 (HSF1) in the response of zebrafish embryos to hypoxia and subsequent return to normoxic conditions (HR) as a model for IR. Heat shock preconditioning elevated heat shock protein expression and protected zebrafish embryo eye and brain tissues against HR-induced apoptosis. These effects were inhibited by translational suppression of HSF1 expression. Reduced expression of HSF1 also increased cell death in brain and eye tissues of embryos subjected to hypoxia and reperfusion without prior heat shock. Surprisingly, reduced expression of HSF1 had only a modest effect on hypoxia-induced expression of Hsp70 and no effect on hypoxia-induced expression of Hsp27. These results establish the zebrafish embryo as a model for the study of ischemic injury in the brain and eye and reveal a critical role for HSF1 in the response of these tissues to HR. Our results also uncouple the role of HSF1 expression from that of Hsp27, a well characterized heat shock protein considered essential for cell survival after hypoxia. Alternative roles for HSF1 are considered.
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Affiliation(s)
- Nathan R. Tucker
- School of Molecular Biosciences, Washington State University, Pullman, Washington, United States of America
| | - Ryan C. Middleton
- School of Molecular Biosciences, Washington State University, Pullman, Washington, United States of America
| | - Quynh P. Le
- School of Molecular Biosciences, Washington State University, Pullman, Washington, United States of America
| | - Eric A. Shelden
- School of Molecular Biosciences, Washington State University, Pullman, Washington, United States of America
- Center for Reproductive Biology, Washington State University, Pullman, Washington, United States of America
- * E-mail:
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Abstract
Heat shock factors form a family of transcription factors (four in mammals), which were named according to the first discovery of their activation by heat shock. As a result of the universality and robustness of their response to heat shock, the stress-dependent activation of heat shock factor became a ‘paradigm’: by binding to conserved DNA sequences (heat shock elements), heat shock factors trigger the expression of genes encoding heat shock proteins that function as molecular chaperones, contributing to establish a cytoprotective state to various proteotoxic stress and in several pathological conditions. Besides their roles in the stress response, heat shock factors perform crucial roles during gametogenesis and development in physiological conditions. First, during these process, in stress conditions, they are either proactive for survival or, conversely, for apoptotic process, allowing elimination or, inversely, protection of certain cell populations in a way that prevents the formation of damaged gametes and secure future reproductive success. Second, heat shock factors display subtle interplay in a tissue- and stage-specific manner, in regulating very specific sets of heat shock genes, but also many other genes encoding growth factors or involved in cytoskeletal dynamics. Third, they act not only by their classical transcription factor activities, but are necessary for the establishment of chromatin structure and, likely, genome stability. Finally, in contrast to the heat shock gene paradigm, heat shock elements bound by heat shock factors in developmental process turn out to be extremely dispersed in the genome, which is susceptible to lead to the future definition of ‘developmental heat shock element’.
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Affiliation(s)
- Ryma Abane
- CNRS, UMR7216 Epigenetics and Cell Fate, Paris, France
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7
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Morrison JC, Cepurna Ying Guo WO, Johnson EC. Pathophysiology of human glaucomatous optic nerve damage: insights from rodent models of glaucoma. Exp Eye Res 2010; 93:156-64. [PMID: 20708000 DOI: 10.1016/j.exer.2010.08.005] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2010] [Revised: 07/28/2010] [Accepted: 08/03/2010] [Indexed: 10/19/2022]
Abstract
Understanding mechanisms of glaucomatous optic nerve damage is essential for developing effective therapies to augment conventional pressure-lowering treatments. This requires that we understand not only the physical forces in play, but the cellular responses that translate these forces into axonal injury. The former are best understood by using primate models, in which a well-developed lamina cribrosa, peripapillary sclera and blood supply are most like that of the human optic nerve head. However, determining cellular responses to elevated intraocular pressure (IOP) and relating their contribution to axonal injury require cell biology techniques, using animals in numbers sufficient to perform reliable statistical analyses and draw meaningful conclusions. Over the years, models of chronically elevated IOP in laboratory rats and mice have proven increasingly useful for these purposes. While lacking a distinct collagenous lamina cribrosa, the rodent optic nerve head (ONH) possesses a cellular arrangement of astrocytes, or glial lamina, that ultrastructurally closely resembles that of the primate. Using these tools, major insights have been gained into ONH and the retinal cellular responses to elevated IOP that, in time, can be applied to the primate model and, ultimately, human glaucoma.
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Affiliation(s)
- John C Morrison
- The Kenneth C. Swan Ocular Neurobiology Laboratory, Casey Eye Institute, Oregon Health and Science University, CERES, 3375 SW Terwilliger Bvld, Portland, OR 97239, USA.
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Rao RC, Tchedre KT, Malik MTA, Coleman N, Fang Y, Marquez VE, Chen DF. Dynamic patterns of histone lysine methylation in the developing retina. Invest Ophthalmol Vis Sci 2010; 51:6784-92. [PMID: 20671280 DOI: 10.1167/iovs.09-4730] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE Histone lysine methylation (HKM) is an important epigenetic mechanism that establishes cell-specific gene expression and functions in development. However, epigenetic control of retinal development is poorly understood. To study the roles of HKM in retinogenesis, the authors examined the dynamic changes of three HKM modifications and of two of their regulators, the histone methyltransferases (HMTases) Ezh2 and G9a, in the mouse retina. METHODS Retinal sections and lysates from embryonic day 16 through adult were processed for immunohistochemistry and immunoblotting using antibodies against various marks and HMTases. To further analyze the biological functions of HKM, the effects of small molecule inhibitors of HMTases were examined in vitro. RESULTS Methylation marks of trimethyl lysine 4 and 27 on histone H3 (H3K4me3 and H3K27me3) were detected primarily in differentiated retinal neurons in the embryonic and adult retina. In contrast, dimethyl lysine 9 on histone H3 (H3K9me2) was noted in early differentiating retinal ganglion cells but was lost after birth. The HMTases controlling H3K27me3, H3K9me2, Ezh2, and G9a were enriched in the inner embryonic retina during the period of active retinogenesis. Using the chemical inhibitors of Ezh2 and G9a, the authors reveal a role for HKM in regulating retinal neuron survival. CONCLUSIONS HKM is a dynamic and spatiotemporally regulated process in the developing retina. Epigenetic regulation of gene transcription by Ezh2- and G9a-mediated HKM plays crucial roles in retinal neuron survival and may represent novel epigenetic targets to enhance viability in retinal neurodegenerative diseases such as glaucoma.
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Affiliation(s)
- Rajesh C Rao
- Schepens Eye Research Institute, Harvard Medical School, Boston, MA 02114, USA
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Chen L, Sham CW, Chan AM, Francisco LM, Wu Y, Mareninov S, Sharpe AH, Freeman GJ, Yang XJ, Braun J, Gordon LK. Role of the immune modulator programmed cell death-1 during development and apoptosis of mouse retinal ganglion cells. Invest Ophthalmol Vis Sci 2009; 50:4941-8. [PMID: 19420345 DOI: 10.1167/iovs.09-3602] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE Mammalian programmed cell death (PD)-1 is a membrane-associated receptor regulating the balance between T-cell activation, tolerance, and immunopathology; however, its role in neurons has not yet been defined. The hypothesis that PD-1 signaling actively promotes retinal ganglion cell (RGC) death within the developing mouse retina was investigated. METHODS Mature retinal cell types expressing PD-1 were identified by immunofluorescence staining of vertical retina sections; developmental expression was localized by immunostaining and quantified by Western blot analysis. PD-1 involvement in developmental RGC survival was assessed in vitro using retinal explants and in vivo using PD-1 knockout mice. PD-1 ligand gene expression was detected by RT-PCR. RESULTS PD-1 is expressed in most adult RGCs and undergoes dynamic upregulation during the early postnatal window of retinal cell maturation and physiological programmed cell death (PCD). In vitro blockade of PD-1 signaling during this time selectively increases the survival of RGCs. Furthermore, PD-1-deficient mice show a selective increase in RGC number in the neonatal retina at the peak of developmental RGC death. Lastly, gene expression of the immune PD-1 ligand genes Pdcd1lg1 and Pdcd1lg2 was found throughout postnatal retina maturation. CONCLUSIONS These findings collectively support a novel role for a PD-1-mediated signaling pathway in developmental PCD during postnatal RGC maturation.
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Affiliation(s)
- Ling Chen
- Department of Molecular and Medical Pharmacology, Jules Stein Eye Institute, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California 90095, USA
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Kim SH, Munemasa Y, Kwong JMK, Ahn JH, Mareninov S, Gordon LK, Caprioli J, Piri N. Activation of autophagy in retinal ganglion cells. J Neurosci Res 2008; 86:2943-51. [PMID: 18521932 DOI: 10.1002/jnr.21738] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Autophagy has been shown to be activated in neuronal cells in response to injury and suggested to have a cell-protective role in neurodegenerative diseases. In this study, we investigated the activation of autophagy in retinal ganglion cells (RGCs) following optic nerve transection (ONT) and evaluated its effect on RGC survival. Expression of several autophagy-related genes, including Atg5, Atg7, and Atg12, and autophagy markers microtubule-associated protein 1 light chain 3-II (LC3-II) and beclin-1 were analyzed at the transcriptional or protein level 1, 3, and 7 days after ONT. Transcription of the Atg5, Atg7, and Atg12 genes was up-regulated 1.5- to 1.8-fold in the retina 3 days after ONT compared with that in the controls. Expression of Atg12 mRNA was increased 1.6-fold 1 day after ONT. Seven days after ONT, expression of Atg5, Atg7, and Atg12 mRNA was comparable to that in the untreated retinas. Western blot analysis of proteins isolated from RGCs showed 1.6-, 2.7-, and 1.7-fold increases in LC3-II level 1, 3, and 7 days after ONT, respectively, compared with those in the controls. Expression of beclin-1 was 1.7-fold higher 1 day after RGCs were axotomized, but 3 and 7 days after ONT it was comparable to that of the control. Inhibition of autophagy with bafilomycin A1, 3-methyladenine, and Wortmannin in RGC-5 cells under serum-deprived conditions decreased cell viability by approximately 40%. These results suggest possible activation of autophagy in RGCs after optic nerve transection and demonstrate its protective role in RGC-5 cells maintained under conditions of serum deprivation.
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Affiliation(s)
- Seok Hwan Kim
- Jules Stein Eye Institute, University of California Los Angeles, Los Angeles, California 90095, USA
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11
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Expression of heat shock transcription factors and heat shock protein 72 in rat retina after intravitreal injection of low dose N-methyl-D-aspartate. Neurosci Lett 2007; 433:11-6. [PMID: 18242848 DOI: 10.1016/j.neulet.2007.12.045] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2007] [Revised: 12/04/2007] [Accepted: 12/14/2007] [Indexed: 11/23/2022]
Abstract
The heat shock response is a genetically well-ordered process for cell to generate heat shock protein (HSP). Various stressors can trigger the response through heat shock transcriptional factor (HSF) regulation. Recent studies demonstrated that preconditioning of N-methyl-d-aspartate (NMDA) at non-lethal levels has neuroprotective effects, but the exact mechanisms are unclear. We hypothesize that the protective mechanisms of NMDA preconditioning could involve HSP expression. To understand the regulatory mechanisms of HSP under stress, we examined the expression of Hsp72, HSF1 and HSF2 in the adult rat retina after intravitreal injection of NMDA. Retinal ganglion cell (RGC) counting with retrograde labeling showed that 8 nmol, but not 0.8 nmol, of intravitreal NMDA reduced RGC survival. Western blotting and immunohistochemistry showed that non-lethal (0.8 nmol) doses of NMDA induced a time-dependent expression of HSF1 and HSF2, and that the expression of HSF1 and HSF2 in the RGC layer peaked between 9 and 18 h after injection. Parallel to the increased HSF expression, immunohistochemistry and in situ hybridization demonstrated that Hsp72 mRNA and protein expression increased 9 and 12 h after non-lethal NMDA injection, respectively. Our findings suggest that the expression of HSF1 and HSF2 is associated with the Hsp72-related stress response.
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Akerfelt M, Trouillet D, Mezger V, Sistonen L. Heat shock factors at a crossroad between stress and development. Ann N Y Acad Sci 2007; 1113:15-27. [PMID: 17483205 DOI: 10.1196/annals.1391.005] [Citation(s) in RCA: 139] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Organisms must be able to sense and respond rapidly to changes in their environment in order to maintain homeostasis and survive. Induction of heat shock proteins (Hsps) is a common cellular defense mechanism for promoting survival in response to various stress stimuli. Heat shock factors (HSFs) are transcriptional regulators of Hsps, which function as molecular chaperones in protecting cells against proteotoxic damage. Mammals have three different HSFs that have been considered functionally distinct: HSF1 is essential for the heat shock response and is also required for developmental processes, whereas HSF2 and HSF4 are important for differentiation and development. Specifically, HSF2 is involved in corticogenesis and spermatogenesis, and HSF4 is needed for maintenance of sensory organs, such as the lens and the olfactory epithelium. Recent evidence, however, suggests a functional interplay between HSF1 and HSF2 in the regulation of Hsp expression under stress conditions. In lens formation, HSF1 and HSF4 have been shown to have opposite effects on gene expression. In this chapter, we present the different roles of the mammalian HSFs as regulators of cellular stress and developmental processes. We highlight the interaction between different HSFs and discuss the discoveries of novel target genes in addition to the classical Hsps.
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Affiliation(s)
- Malin Akerfelt
- Turku Centre for Biotechnology, P.O. Box 123, FI-20521 Turku, Finland
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