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Shrestha SK, Lachke SA. Lens Regeneration: The Application of iSyTE and In Silico Approaches to Evaluate Gene Expression in Lens Organoids. Methods Mol Biol 2025; 2848:37-58. [PMID: 39240515 DOI: 10.1007/978-1-0716-4087-6_3] [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] [Indexed: 09/07/2024]
Abstract
Several protocols have been established for the generation of lens organoids from embryonic stem cells (ESCs), induced pluripotent stem cells (iPSCs), and other cells with regenerative potential in humans or various animal models. It is important to examine how well the regenerated lens organoids reflect lens biology, in terms of its development, homeostasis, and aging. Toward this goal, the iSyTE database (integrated Systems Tool for Eye gene discovery; https://research.bioinformatics.udel.edu/iSyTE/ ), a bioinformatics resource tool that contains meta-analyzed gene expression data in wild-type lens across different embryonic, postnatal, and adult stages, can serve as a resource for comparative analysis. This article outlines the approaches toward effective use of iSyTE to gain insights into normal gene expression in the mouse lens, enriched expression in the lens, and differential gene expression in select mouse gene-perturbation cataract/lens defects models, which in turn can be used to evaluate expression of key lens-relevant genes in lens organoids by transcriptomics (e.g., RNA-sequencing (RNA-seq), microarrays, etc.) or other downstream methods (e.g., RT-qPCR, etc.).
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Affiliation(s)
- Sanjaya K Shrestha
- Department of Biological Sciences, University of Delaware, Newark, DE, USA
| | - Salil A Lachke
- Department of Biological Sciences, University of Delaware, Newark, DE, USA.
- Center for Bioinformatics & Computational Biology, University of Delaware, Newark, DE, USA.
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2
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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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3
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Xiang J, Pompetti AJ, Faranda AP, Wang Y, Novo SG, Li DWC, Duncan MK. ATF4 May Be Essential for Adaption of the Ocular Lens to Its Avascular Environment. Cells 2023; 12:2636. [PMID: 37998373 PMCID: PMC10670291 DOI: 10.3390/cells12222636] [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: 03/23/2023] [Revised: 10/30/2023] [Accepted: 11/03/2023] [Indexed: 11/25/2023] Open
Abstract
The late embryonic mouse lens requires the transcription factor ATF4 for its survival although the underlying mechanisms were unknown. Here, RNAseq analysis revealed that E16.5 Atf4 null mouse lenses downregulate the mRNA levels of lens epithelial markers as well as known markers of late lens fiber cell differentiation. However, a comparison of this list of differentially expressed genes (DEGs) with other known transcriptional regulators of lens development indicated that ATF4 expression is not directly controlled by the previously described lens gene regulatory network. Pathway analysis revealed that the Atf4 DEG list was enriched in numerous genes involved in nutrient transport, amino acid biosynthesis, and tRNA charging. These changes in gene expression likely result in the observed reductions in lens free amino acid and glutathione levels, which would result in the observed low levels of extractable lens protein, finally leading to perinatal lens disintegration. These data demonstrate that ATF4, via its function in the integrated stress response, is likely to play a crucial role in mediating the adaption of the lens to the avascularity needed to maintain lens transparency.
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Affiliation(s)
- Jiawen Xiang
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
- The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510230, China
| | - Anthony J. Pompetti
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - Adam P. Faranda
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - Yan Wang
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - Samuel G. Novo
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - David Wan-Cheng Li
- The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510230, China
| | - Melinda K. Duncan
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
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4
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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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5
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Thompson B, Chen Y, Davidson EA, Garcia-Milian R, Golla JP, Apostolopoulos N, Orlicky DJ, Schey K, Thompson DC, Vasiliou V. Impaired GSH biosynthesis disrupts eye development, lens morphogenesis and PAX6 function. Ocul Surf 2021; 22:190-203. [PMID: 34425299 DOI: 10.1016/j.jtos.2021.08.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 07/29/2021] [Accepted: 08/16/2021] [Indexed: 12/14/2022]
Abstract
PURPOSE The purpose of this study was to elucidate the role and molecular consequences of impaired glutathione (GSH) biosynthesis on eye development. METHODS GSH biosynthesis was impaired in surface ectoderm-derived ocular tissues by crossing Gclcf/f mice with hemizygous Le-Cre transgenic mice to produce Gclcf/f/Le-CreTg/- (KO) mice. Control mice included Gclcf/fand Gclcwt/wt/Le-CreTg/- mice (CRE). Eyes from all mice (at various stages of eye development) were subjected to histological, immunohistochemical, Western blot, RT-qPCR, RNA-seq, and subsequent Gene Ontology, Ingenuity Pathway Analysis and TRANSFAC analyses. PAX6 transactivation activity was studied using a luciferase reporter assay in HEK293T cells depleted of GSH using buthionine sulfoximine (BSO). RESULTS Deletion of Gclc diminished GSH levels, increased reactive oxygen species (ROS), and caused an overt microphthalmia phenotype characterized by malformation of the cornea, iris, lens, and retina that is distinct from and much more profound than the one observed in CRE mice. In addition, only the lenses of KO mice displayed reduced crystallin (α, β), PITX3 and Foxe3 expression. RNA-seq analyses at postnatal day 1 revealed 1552 differentially expressed genes (DEGs) in the lenses of KO mice relative to those from Gclcf/f mice, with Crystallin and lens fiber cell identity genes being downregulated while lens epithelial cell identity and immune response genes were upregulated. Bioinformatic analysis of the DEGs implicated PAX6 as a key upstream regulator. PAX6 transactivation activity was impaired in BSO-treated HEK293T cells. CONCLUSIONS These data suggest that impaired ocular GSH biosynthesis may disrupt eye development and PAX6 function.
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Affiliation(s)
- Brian Thompson
- Department of Environmental Health Sciences, Yale School of Public Health, Yale University, 60 College Street, New Haven, CT, USA
| | - Ying Chen
- Department of Environmental Health Sciences, Yale School of Public Health, Yale University, 60 College Street, New Haven, CT, USA
| | - Emily A Davidson
- Department of Environmental Health Sciences, Yale School of Public Health, Yale University, 60 College Street, New Haven, CT, USA; Department of Cellular & Molecular Physiology, Yale School of Medicine, Yale University, New Haven, CT, USA
| | - Rolando Garcia-Milian
- Bioinformatics Support Program, Cushing/Whitney Medical Library, Yale School of Medicine, New Haven, CT, USA
| | - Jaya Prakash Golla
- Department of Environmental Health Sciences, Yale School of Public Health, Yale University, 60 College Street, New Haven, CT, USA; Department of Medicine, Yale University School of Medicine, New Haven, CT, USA; Veterans Affairs Connecticut Healthcare System, West Haven, CT, USA
| | | | - David J Orlicky
- Department of Pathology, Anschutz School of Medicine, University of Colorado, Aurora, CO, USA
| | - Kevin Schey
- Department of Biochemistry and Mass Spectrometry Research Center, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - David C Thompson
- Department of Clinical Pharmacy, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver, Aurora, CO, USA
| | - Vasilis Vasiliou
- Department of Environmental Health Sciences, Yale School of Public Health, Yale University, 60 College Street, New Haven, CT, USA.
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6
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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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7
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Ali M, Kabir F, Raskar S, Renuse S, Na CH, Delannoy M, Khan SY, Riazuddin SA. Generation and proteome profiling of PBMC-originated, iPSC-derived lentoid bodies. Stem Cell Res 2020; 46:101813. [PMID: 32474394 DOI: 10.1016/j.scr.2020.101813] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 03/18/2020] [Accepted: 04/09/2020] [Indexed: 01/13/2023] Open
Abstract
Here, we report proteome profiling of peripheral blood mononuclear cell (PBMC)-originated, induced pluripotent stem cell (iPSC)-derived, lens-like organoids termed lentoid bodies at two differentiation time points. A small aliquot of the blood sample was ascertained to collect PBMCs that were reprogrammed to iPSCs. The PBMC-originated, iPSCs were differentiated to lentoid bodies employing the "fried egg" method. Quantitative real-time PCR (qRT-PCR) analysis revealed increased expression levels of lens-associated markers in lentoid bodies while transmission electron microscopy identified closely packed lens epithelial- and differentiating fiber-like cells in lentoid bodies. Total cellular protein was extracted from lentoid bodies at differentiation day 25 and mass spectrometry identified a total of 9,473 proteins. The low counts of crystallin proteins at differentiation day 25 prompted us to re-examine the proteome at differentiation day 35 as we reasoned that 10 additional days of differentiation will increase the crystallin count. However, we did not detect any substantial increase in crystallin protein counts at differentiation day 35. In conclusion, we report generation and proteome profiles of PBMC-originated, iPSC-derived lentoid bodies at multiple differentiation time points.
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Affiliation(s)
- Muhammad Ali
- The Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Firoz Kabir
- The Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Snehal Raskar
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Santosh Renuse
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Chan Hyun Na
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Michael Delannoy
- Department of Cell Biology and Imaging Facility, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Shahid Y Khan
- The Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - S Amer Riazuddin
- The Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
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8
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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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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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10
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Lam PT, Padula SL, Hoang TV, Poth JE, Liu L, Liang C, LeFever AS, Wallace LM, Ashery-Padan R, Riggs PK, Shields JE, Shaham O, Rowan S, Brown NL, Glaser T, Robinson ML. Considerations for the use of Cre recombinase for conditional gene deletion in the mouse lens. Hum Genomics 2019; 13:10. [PMID: 30770771 PMCID: PMC6377743 DOI: 10.1186/s40246-019-0192-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Accepted: 01/22/2019] [Indexed: 12/03/2022] Open
Abstract
Background Despite a number of different transgenes that can mediate DNA deletion in the developing lens, each has unique features that can make a given transgenic line more or less appropriate for particular studies. The purpose of this work encompasses both a review of transgenes that lead to the expression of Cre recombinase in the lens and a comparative analysis of currently available transgenic lines with a particular emphasis on the Le-Cre and P0-3.9GFPCre lines that can mediate DNA deletion in the lens placode. Although both of these transgenes are driven by elements of the Pax6 P0 promoter, the Le-Cre transgene consistently leads to ocular abnormalities in homozygous state and can lead to ocular defects on some genetic backgrounds when hemizygous. Result Although both P0-3.9GFPCre and Le-Cre hemizygous transgenic mice undergo normal eye development on an FVB/N genetic background, Le-Cre homozygotes uniquely exhibit microphthalmia. Examination of the expression patterns of these two transgenes revealed similar expression in the developing eye and pancreas. However, lineage tracing revealed widespread non-ocular CRE reporter gene expression in the P0-3.9GFPCre transgenic mice that results from stochastic CRE expression in the P0-3.9GFPCre embryos prior to lens placode formation. Postnatal hemizygous Le-Cre transgenic lenses express higher levels of CRE transcript and protein than the hemizygous lenses of P0-3.9GFPCre mice. Transcriptome analysis revealed that Le-Cre hemizygous lenses deregulated the expression of 15 murine genes, several of which are associated with apoptosis. In contrast, P0-3.9GFPCre hemizygous lenses only deregulated two murine genes. No known PAX6-responsive genes or genes directly associated with lens differentiation were deregulated in the hemizygous Le-Cre lenses. Conclusions Although P0-3.9GFPCre transgenic mice appear free from ocular abnormalities, extensive non-ocular CRE expression represents a potential problem for conditional gene deletion studies using this transgene. The higher level of CRE expression in Le-Cre lenses versus P0-3.9GFPCre lenses may explain abnormal lens development in homozygous Le-Cre mice. Given the lack of deregulation of PAX6-responsive transcripts, we suggest that abnormal eye development in Le-Cre transgenic mice stems from CRE toxicity. Our studies reinforce the requirement for appropriate CRE-only expressing controls when using CRE as a driver of conditional gene targeting strategies. Electronic supplementary material The online version of this article (10.1186/s40246-019-0192-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Phuong T Lam
- Department of Biology, Miami University, Oxford, OH, 45056, USA
| | | | - Thanh V Hoang
- Department of Biology, Miami University, Oxford, OH, 45056, USA.,Present Address: Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Justin E Poth
- 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
| | - Adam S LeFever
- Nuclear Medicine Department, University of Cincinnati Medical Center, 234 Goodman Street, Cincinnati, OH, 45219, USA
| | - Lindsay M Wallace
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, OH, 43205, USA
| | - Ruth Ashery-Padan
- Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine, Sagol School of Neurosciences, Tel Aviv University, 69978, Tel Aviv, Israel
| | - Penny K Riggs
- Department of Animal Sciences, Texas A&M University, College Station, TX, 77843-2471, USA
| | - Jordan E Shields
- Department of Animal Sciences, Texas A&M University, College Station, TX, 77843-2471, USA.,Present Address: Emory Children's Center, Room 410, 2015 Uppergate Drive, Atlanta, GA, 30322, USA
| | - Ohad Shaham
- Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine, Sagol School of Neurosciences, Tel Aviv University, 69978, Tel Aviv, Israel
| | - Sheldon Rowan
- Department of Ophthalmology, Tufts University School of Medicine, Boston, MA, 02111, USA
| | - Nadean L Brown
- Department of Cell Biology and Human Anatomy, University of California, Davis One Shields Avenue, Davis, CA, 95616, USA
| | - Tom Glaser
- Department of Cell Biology and Human Anatomy, University of California, Davis One Shields Avenue, Davis, CA, 95616, USA
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11
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Gangalum RK, Kim D, Kashyap RK, Mangul S, Zhou X, Elashoff D, Bhat SP. Spatial Analysis of Single Fiber Cells of the Developing Ocular Lens Reveals Regulated Heterogeneity of Gene Expression. iScience 2018; 10:66-79. [PMID: 30508719 PMCID: PMC6277220 DOI: 10.1016/j.isci.2018.11.024] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Revised: 11/08/2018] [Accepted: 11/13/2018] [Indexed: 01/19/2023] Open
Abstract
The developing eye lens presents an exceptional paradigm for spatial transcriptomics. It is composed of highly organized long, slender transparent fiber cells, which differentiate from the edges of the anterior epithelium of the lens (equator), attended by high expression of crystallins, which generates transparency. Every fiber cell, therefore, is an optical unit whose refractive properties derive from its gene activity. Here, we probe this tangible relationship between the gene activity and the phenotype by studying the expression of all known 17 crystallins and 77 other non-crystallin genes in single fiber cells isolated from three states/regions of differentiation, allowing us to follow molecular progression at the single-cell level. The data demonstrate highly variable gene activity in cortical fibers, interposed between the nascent and the terminally differentiated fiber cell transcription. These data suggest that the so-called stochastic, highly heterogeneous gene activity is a regulated intermediate in the realization of a functional phenotype.
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Affiliation(s)
- Rajendra K Gangalum
- Stein Eye Institute, Geffen School of Medicine, University of California, Los Angeles, CA 90095-7000, USA
| | - Dongjae Kim
- Stein Eye Institute, Geffen School of Medicine, University of California, Los Angeles, CA 90095-7000, USA
| | - Raj K Kashyap
- Stein Eye Institute, Geffen School of Medicine, University of California, Los Angeles, CA 90095-7000, USA
| | - Serghei Mangul
- Department of Computer Science and Human Genetics, University of California, Los Angeles, CA 90095-7000, USA
| | - Xinkai Zhou
- Department of Medicine, University of California, Los Angeles, CA 90095-7000, USA
| | - David Elashoff
- Department of Medicine, University of California, Los Angeles, CA 90095-7000, USA
| | - Suraj P Bhat
- Stein Eye Institute, Geffen School of Medicine, University of California, Los Angeles, CA 90095-7000, USA; Brain Research Institute, University of California, Los Angeles, CA 90095-7000, USA; Molecular Biology Institute, University of California, Los Angeles, CA 90095-7000, USA.
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12
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Anand D, Kakrana A, Siddam AD, Huang H, Saadi I, Lachke SA. RNA sequencing-based transcriptomic profiles of embryonic lens development for cataract gene discovery. Hum Genet 2018; 137:941-954. [PMID: 30417254 DOI: 10.1007/s00439-018-1958-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Accepted: 11/07/2018] [Indexed: 12/21/2022]
Abstract
Isolated or syndromic congenital cataracts are heterogeneous developmental defects, making the identification of the associated genes challenging. In the past, mouse lens expression microarrays have been successfully applied in bioinformatics tools (e.g., iSyTE) to facilitate human cataract-associated gene discovery. To develop a new resource for geneticists, we report high-throughput RNA sequencing (RNA-seq) profiles of mouse lens at key embryonic stages (E)10.5 (lens pit), E12.5 (primary fiber cell differentiation), E14.5 and E16.5 (secondary fiber cell differentiation). These stages capture important events as the lens develops from an invaginating placode into a transparent tissue. Previously, in silico whole-embryo body (WB)-subtraction-based "lens-enriched" expression has been effective in prioritizing cataract-linked genes. To apply an analogous approach, we generated new mouse WB RNA-seq datasets and show that in silico WB subtraction of lens RNA-seq datasets successfully identifies key genes based on lens-enriched expression. At ≥2 counts-per-million expression, ≥1.5 log2 fold-enrichment (p < 0.05) cutoff, E10.5 lens exhibits 1401 enriched genes (17% lens-expressed genes), E12.5 lens exhibits 1937 enriched genes (22% lens-expressed genes), E14.5 lens exhibits 2514 enriched genes (31% lens-expressed genes), and E16.5 lens exhibits 2745 enriched genes (34% lens-expressed genes). Biological pathway analysis identified genes associated with lens development, transcription regulation and signaling pathways, among other functional groups. Furthermore, these new RNA-seq data confirmed high expression of established cataract-linked genes and identified new potential regulators in the lens. Finally, we developed new lens stage-specific UCSC Genome Brower annotation tracks and made these publicly accessible through iSyTE ( https://research.bioinformatics.udel.edu/iSyTE/ ) for user-friendly visualization of lens gene expression/enrichment to prioritize genes from high-throughput data from cataract cases.
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Affiliation(s)
- Deepti Anand
- Department of Biological Sciences, University of Delaware, 105 The Green, Delaware Avenue, 236 Wolf Hall, Newark, DE, 19716, USA
| | - Atul Kakrana
- Center for Bioinformatics and Computational Biology, University of Delaware, Newark, DE, 19716, USA
| | - Archana D Siddam
- Department of Biological Sciences, University of Delaware, 105 The Green, Delaware Avenue, 236 Wolf Hall, Newark, DE, 19716, USA
| | - Hongzhan Huang
- Center for Bioinformatics and Computational Biology, University of Delaware, Newark, DE, 19716, USA
| | - Irfan Saadi
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - Salil A Lachke
- Department of Biological Sciences, University of Delaware, 105 The Green, Delaware Avenue, 236 Wolf Hall, Newark, DE, 19716, USA. .,Center for Bioinformatics and Computational Biology, University of Delaware, Newark, DE, 19716, USA.
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13
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Rosner A, Kravchenko O, Rinkevich B. IAP genes partake weighty roles in the astogeny and whole body regeneration in the colonial urochordate Botryllus schlosseri. Dev Biol 2018; 448:320-341. [PMID: 30385275 DOI: 10.1016/j.ydbio.2018.10.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 09/29/2018] [Accepted: 10/17/2018] [Indexed: 12/12/2022]
Abstract
Inhibitors of Apoptosis Protein (IAP) genes participate in processes like apoptosis, proliferation, innate immunity, inflammation, cell motility, differentiation and in malignancies. Here we reveal 25 IAP genes in the tunicate Botryllus schlosseri's genome and their functions in two developmental biology phenomena, a new mode of whole body regeneration (WBR) induced by budectomy, and blastogenesis, the four-staged cycles of botryllid ascidian astogeny. IAP genes that were specifically upregulated during these developmental phenomena were identified, and protein expression patterns of one of these genes, IAP28, were followed. Most of the IAP genes upregulation recorded at blastogenetic stages C/D was in concert with the upregulation at 100 μM H2O2 apoptotic-induced treatment and in parallel to expressions of AIF1, Bax, Mcl1, caspase 2 and two orthologues of caspase 7. Wnt agonist altered the takeover duration along with reduced IAP expressions, and displacement of IAP28+ phagocytes. WBR was initiated solely at blastogenetic stage D, where zooidal absorption was attenuated and regeneration centers were formed either from remains of partially absorbed zooids or from deformed ampullae. Subsequently, bud-bearing zooids developed, in concert with a massive IAP28-dependent phagocytic wave that eliminated the old zooids, then proceeded with the establishment of morphologically normal-looking colonies. IAP4, IAP14 and IAP28 were also involved in WBR, in conjunction with the expression of the pro-survival PI3K-Akt pathway. IAPs function deregulation by Smac mimetics resulted in severe morphological damages, attenuation in bud growth and differentiation, and in destabilization of colonial coordination. Longtime knockdown of IAP functions prior to the budectomy, resulted in colonial death.
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Affiliation(s)
- Amalia Rosner
- Israel Oceanographic&Limnological Research Institute, Tel Shikmona, P.O.B. 8030, Haifa 31080, Israel.
| | - Olha Kravchenko
- Israel Oceanographic&Limnological Research Institute, Tel Shikmona, P.O.B. 8030, Haifa 31080, Israel; National University of Life and Environmental Sciences of Ukraine, Heroiv Oborony, Str 17, building 2, of 45, Kyiv 03041, Ukraine
| | - Baruch Rinkevich
- Israel Oceanographic&Limnological Research Institute, Tel Shikmona, P.O.B. 8030, Haifa 31080, Israel
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14
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Galichanin K. Exposure to subthreshold dose of UVR-B induces apoptosis in the lens epithelial cells and does not in the lens cortical fibre cells. Acta Ophthalmol 2017; 95:834-838. [PMID: 28083904 DOI: 10.1111/aos.13370] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 11/19/2016] [Indexed: 01/20/2023]
Abstract
PURPOSE The aim of this study was to investigate in which part of the lens in vivo exposure to subthreshold dose of UVR-B radiation induces apoptosis. METHODS Twenty 6-week-old female albino Sprague-Dawley rats were exposed to subthreshold dose (1 kJ/m2 ) of UVR-B unilaterally and killed at 120 hr after exposure. Lenses were enucleated and dissected on three regions: the lens epithelium, the cortex and the nucleus. The lens nucleus then was removed. Apoptosis markers p53 and caspase 3 were used to study apoptosis in the lens regions. qRT-PCR and Western blot were utilized to analyse the lenses. RESULTS TP53 and CASP3 mRNA expressions are increased in exposed lenses, both in the lens epithelium and in the cortex regions, in relation to non-exposed lenses. Expression of p53 protein is increased in exposed lens epithelium in relation to non-exposed lens epithelium. Caspase 3 protein is expressed in exposed lens epithelial cells, while it is not expressed in non-exposed lens epithelial cells. p53 and caspase 3 proteins are not expressed in either exposed nor non-exposed lens fibre cells. CONCLUSION Exposure to UVR-B increases mRNA transcription of apoptosis marker p53 in vivo in both regions of the lens and of apoptosis marker caspase 3 in the lens cortex. Exposure to UVR-B increases p53 and caspase 3 proteins expression just in the lens epithelium. In vivo exposure to subthreshold dose of UVR-B induces apoptosis in the lens epithelial cells and does not in the lens fibre cells.
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Affiliation(s)
- Konstantin Galichanin
- Gullstrand lab; Section of Ophthalmology; Department of Neuroscience; Uppsala University; Uppsala Sweden
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15
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Dash S, Siddam AD, Barnum CE, Janga SC, Lachke SA. RNA-binding proteins in eye development and disease: implication of conserved RNA granule components. WILEY INTERDISCIPLINARY REVIEWS-RNA 2016; 7:527-57. [PMID: 27133484 DOI: 10.1002/wrna.1355] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 03/21/2016] [Indexed: 01/16/2023]
Abstract
The molecular biology of metazoan eye development is an area of intense investigation. These efforts have led to the surprising recognition that although insect and vertebrate eyes have dramatically different structures, the orthologs or family members of several conserved transcription and signaling regulators such as Pax6, Six3, Prox1, and Bmp4 are commonly required for their development. In contrast, our understanding of posttranscriptional regulation in eye development and disease, particularly regarding the function of RNA-binding proteins (RBPs), is limited. We examine the present knowledge of RBPs in eye development in the insect model Drosophila as well as several vertebrate models such as fish, frog, chicken, and mouse. Interestingly, of the 42 RBPs that have been investigated for their expression or function in vertebrate eye development, 24 (~60%) are recognized in eukaryotic cells as components of RNA granules such as processing bodies, stress granules, or other specialized ribonucleoprotein (RNP) complexes. We discuss the distinct developmental and cellular events that may necessitate potential RBP/RNA granule-associated RNA regulon models to facilitate posttranscriptional control of gene expression in eye morphogenesis. In support of these hypotheses, three RBPs and RNP/RNA granule components Tdrd7, Caprin2, and Stau2 are linked to ocular developmental defects such as congenital cataract, Peters anomaly, and microphthalmia in human patients or animal models. We conclude by discussing the utility of interdisciplinary approaches such as the bioinformatics tool iSyTE (integrated Systems Tool for Eye gene discovery) to prioritize RBPs for deriving posttranscriptional regulatory networks in eye development and disease. WIREs RNA 2016, 7:527-557. doi: 10.1002/wrna.1355 For further resources related to this article, please visit the WIREs website.
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Affiliation(s)
- Soma Dash
- Department of Biological Sciences, University of Delaware, Newark, DE, USA
| | - Archana D Siddam
- Department of Biological Sciences, University of Delaware, Newark, DE, USA
| | - Carrie E Barnum
- Department of Biological Sciences, University of Delaware, Newark, DE, USA
| | - Sarath Chandra Janga
- Department of Biohealth Informatics, School of Informatics and Computing, Indiana University & Purdue University Indianapolis, Indianapolis, IN, USA.,Center for Computational Biology and Bioinformatics, Indiana University School of Medicine, Indianapolis, IN, 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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16
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Anand D, Lachke SA. Systems biology of lens development: A paradigm for disease gene discovery in the eye. Exp Eye Res 2016; 156:22-33. [PMID: 26992779 DOI: 10.1016/j.exer.2016.03.010] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Revised: 03/08/2016] [Accepted: 03/11/2016] [Indexed: 12/19/2022]
Abstract
Over the past several decades, the biology of the developing lens has been investigated using molecular genetics-based approaches in various vertebrate model systems. These efforts, involving target gene knockouts or knockdowns, have led to major advances in our understanding of lens morphogenesis and the pathological basis of cataracts, as well as of other lens related eye defects. In particular, we now have a functional understanding of regulators such as Pax6, Six3, Sox2, Oct1 (Pou2f1), Meis1, Pnox1, Zeb2 (Sip1), Mab21l1, Foxe3, Tfap2a (Ap2-alpha), Pitx3, Sox11, Prox1, Sox1, c-Maf, Mafg, Mafk, Hsf4, Fgfrs, Bmp7, and Tdrd7 in this tissue. However, whether these individual regulators interact or their targets overlap, and the significance of such interactions during lens morphogenesis, is not well defined. The arrival of high-throughput approaches for gene expression profiling (microarrays, RNA-sequencing (RNA-seq), etc.), which can be coupled with chromatin immunoprecipitation (ChIP) or RNA immunoprecipitation (RIP) assays, along with improved computational resources and publically available datasets (e.g. those containing comprehensive protein-protein, protein-DNA information), presents new opportunities to advance our understanding of the lens tissue on a global systems level. Such systems-level knowledge will lead to the derivation of the underlying lens gene regulatory network (GRN), defined as a circuit map of the regulator-target interactions functional in lens development, which can be applied to expedite cataract gene discovery. In this review, we cover the various systems-level approaches such as microarrays, RNA-seq, and ChIP that are already being applied to lens studies and discuss strategies for assembling and interpreting these vast amounts of high-throughput information for effective dispersion to the scientific community. In particular, we discuss strategies for effective interpretation of this new information in the context of the rich knowledge obtained through the application of traditional single-gene focused experiments on the lens. Finally, we discuss our vision for integrating these diverse high-throughput datasets in a single web-based user-friendly tool iSyTE (integrated Systems Tool for Eye gene discovery) - a resource that is already proving effective in the identification and characterization of genes linked to lens development and cataract. We anticipate that application of a similar approach to other ocular tissues such as the retina and the cornea, and even other organ systems, will significantly impact disease gene discovery.
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Affiliation(s)
- Deepti Anand
- Department of Biological Sciences, University of Delaware, Newark, DE, 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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