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Luo X, Song S, Qi L, Tien CL, Li H, Xu W, Mathuram TL, Burris T, Zhao Y, Sun Z, Zhang L. REV-ERB is essential in cardiac fibroblasts homeostasis. Front Pharmacol 2022; 13:899628. [PMID: 36386186 PMCID: PMC9662302 DOI: 10.3389/fphar.2022.899628] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Accepted: 10/10/2022] [Indexed: 01/28/2023] Open
Abstract
REV-ERB agonists have shown antifibrotic effects in the heart and other organs. The function of REV-ERB in the cardiac fibroblasts remains unstudied. Here, we characterize the functional difference of REV-ERB in mouse embryonic fibroblasts and cardiac fibroblasts using genetic deletion of REV-ERBα and ß in vitro. We show that REV-ERB α/β double deleted cardiac fibroblasts have reduced viability and proliferation, but increased migration and myofibroblasts activation. Thus, REV-ERB α/β has essential cell-autonomous role in cardiac fibroblasts in maintaining them in a healthy, quiescent state. We also show that existing REV-ERB agonist SR9009 strongly suppresses cardiac fibroblasts activation but in a REV-ERB-independent manner highlighting the need to develop novel REV-ERB agonists for treating cardiac fibrosis.
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Affiliation(s)
- Xiaokang Luo
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
| | - Shiyang Song
- Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Baylor College of Medicine, Houston, TX, United States
| | - Lei Qi
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
| | - Chih-Liang Tien
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
| | - Hui Li
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
| | - Weiyi Xu
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
| | - Theodore Lemuel Mathuram
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
| | - Thomas Burris
- Genetics Institute, University of Florida, Gainesville, FL, United States
| | - Yuanbiao Zhao
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
| | - Zheng Sun
- Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Baylor College of Medicine, Houston, TX, United States
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, United States
| | - Lilei Zhang
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
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2
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Song S, Tien CL, Cui H, Basil P, Zhu N, Gong Y, Li W, Li H, Fan Q, Choi JM, Luo W, Xue Y, Cao R, Zhou W, Ortiz AR, Stork B, Mundra V, Putluri N, York B, Chu M, Chang J, Jung SY, Xie L, Song J, Zhang L, Sun Z. Myocardial Rev-erb-Mediated Diurnal Metabolic Rhythm and Obesity Paradox. Circulation 2022; 145:448-464. [PMID: 35034472 PMCID: PMC8812427 DOI: 10.1161/circulationaha.121.056076] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Supplemental Digital Content is available in the text. The nuclear receptor Rev-erbα/β, a key component of the circadian clock, emerges as a drug target for heart diseases, but the function of cardiac Rev-erb has not been studied in vivo. Circadian disruption is implicated in heart diseases, but it is unknown whether cardiac molecular clock dysfunction is associated with the progression of any naturally occurring human heart diseases. Obesity paradox refers to the seemingly protective role of obesity for heart failure, but the mechanism is unclear.
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Affiliation(s)
- Shiyang Song
- Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Baylor College of Medicine, Houston, Texas; Children's Heart Center, Institute of Cardiovascular Development and Translational Medicine, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Chih-Liang Tien
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas
| | - Hao Cui
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital; National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences (CAMS) and Peking Union Medical College (PUMC), Beijing, China
| | - Paul Basil
- Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Baylor College of Medicine, Houston, Texas; Department of Critical Care, Division of Anesthesiology, Critical Care and Pain Medicine, University of Texas MD Anderson Cancer Center, Houston, TX
| | - Ningxia Zhu
- Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Baylor College of Medicine, Houston, Texas
| | - Yingyun Gong
- Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Baylor College of Medicine, Houston, Texas
| | - Wenbo Li
- Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Baylor College of Medicine, Houston, Texas
| | - Hui Li
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas
| | - Qiying Fan
- Department of Medicine, Division of Atherosclerosis and Vascular Medicine, Cardiovascular Research Institute (CVRI), Houston, TX
| | - Jong Min Choi
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX
| | - Weijia Luo
- Center for Genomic and Precision Medicine, Texas A&M University, Institute of Biosciences and Technology, Houston, TX
| | - Yanfeng Xue
- Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Baylor College of Medicine, Houston, Texas
| | - Rui Cao
- Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Baylor College of Medicine, Houston, Texas
| | - Wenjun Zhou
- Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Baylor College of Medicine, Houston, Texas
| | - Andrea R Ortiz
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX
| | - Brittany Stork
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX
| | - Vatsala Mundra
- Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Baylor College of Medicine, Houston, Texas
| | - Nagireddy Putluri
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX
| | - Brian York
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX
| | - Maoping Chu
- Children's Heart Center, Institute of Cardiovascular Development and Translational Medicine, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Jiang Chang
- Center for Genomic and Precision Medicine, Texas A&M University, Institute of Biosciences and Technology, Houston, TX
| | - Sung Yun Jung
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX
| | - Liang Xie
- Department of Medicine, Division of Atherosclerosis and Vascular Medicine, Cardiovascular Research Institute (CVRI), Houston, TX
| | - Jiangping Song
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital; National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences (CAMS) and Peking Union Medical College (PUMC), Beijing, China
| | - Lilei Zhang
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas
| | - Zheng Sun
- Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Baylor College of Medicine, Houston, Texas; Department of Medicine, Division of Atherosclerosis and Vascular Medicine, Cardiovascular Research Institute (CVRI), Houston, TX
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3
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Tien CL, Mohammadparast S, Chang C. Heterochromatin protein 1 beta regulates neural and neural crest development by repressing pluripotency-associated gene pou5f3.2/oct25 in Xenopus. Dev Dyn 2021; 250:1113-1124. [PMID: 33595886 DOI: 10.1002/dvdy.319] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 02/09/2021] [Accepted: 02/09/2021] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND Heterochromatin protein 1 (HP1) is associated with and plays a role in compact chromatin conformation, but the function of HP1 in vertebrate embryogenesis is not understood completely. RESULTS Here, we explore the activity of HP1 in early neural development in the frog Xenopus laevis. We show that the three isoforms of HP1, HP1α, β, and γ, are expressed in similar patterns in the neural and neural crest derivatives in early embryos. Despite this, knockdown of HP1β and HP1γ, but not HP1α, in presumptive neural tissues leads to head defects. Late pan-neural markers and neural crest specifier genes are reduced, but early neural and neural plate border genes are less affected in the morphant embryos. Further investigation reveals that neuronal differentiation is impaired and a pluripotency-associated gene, pou5f3.2/oct25, is expanded in HP1β morphants. Ectopic expression of pou5f3.2/oct25 mimics the effect of HP1β knockdown on marker expression, whereas simultaneous knockdown of HP1β and pou5f3.2/oct25 partially rescues expression of these genes. CONCLUSION Taken together, the data suggest that HP1β regulates transition from precursor to more differentiated cell types during neural and neural crest development in Xenopus, and it does so at least partially via repression of the pluripotency-associated transcription regulator pou5f3.2/oct25.
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Affiliation(s)
- Chih-Liang Tien
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Saeid Mohammadparast
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Chenbei Chang
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama, USA
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4
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Affiliation(s)
- Le Li
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77004, USA
- Department of Anesthesiology, Zhujiang hospital, Southern Medical University, Guangzhou, Guangdong 510282, China
| | - Hui Li
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77004, USA
| | - Chih-Liang Tien
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77004, USA
| | - Mukesh K. Jain
- Case Cardiovascular Research Institute, Department of Medicine, Harrington Heart and Vascular Institute, University Hospitals Cleveland Medical Center, Cleveland, Ohio 44106, USA
- School of Medicine, Case Western Reserve University, Cleveland, Ohio 44106, USA
| | - Lilei Zhang
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77004, USA
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5
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Li L, Li H, Tien CL, Zhang R, Liao X, Jain MK, Zhang L. Abstract 431: KLF15 Regulates the Circadian Susceptibility to Ischemia Reperfusion Injury in the Heart. Circ Res 2018. [DOI: 10.1161/res.123.suppl_1.431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The onset and the injury of heart attacks both show a circadian rhythmicity with a peak during the sleep to active transition. Studies using cell type specific clock mutant demonstrated the intrinsic varying susceptibility of the cardiomyocytes to the ischemia reperfusion (I/R) injury in a time-of-the-day dependent fashion, however, the molecular mechanisms remain unclear. Transcription factor KLF15 expresses in a circadian fashion and is significantly reduced in ischemia cardiomyopathy in human and in mice, but its role in the cardiac I/R injury is unknown. Recently, we show that KLF15 coordinates the diurnal expression of catabolic genes in the heart during the active phase, suggesting it may also be involved in regulating the cardiac reactive oxygen species (ROS), which is not only a byproduct of catabolism but also the main injury during reperfusion. Here we show that cardiomyocyte specific KLF15 deficient mice have exaggerated I/R injury in vivo during the sleep to active transition when KLF15 expression is at peak, but not during the active to sleep transition, demonstrating its critical role in governing the circadian rhythmicity of myocardial injury. We found acute KLF15 deficiency in the primary cardiomyocytes is associated with increased ROS and exaggerated susceptibility to oxidative stress, which can be rescued by a MnSOD mimetic Tempol, but not by several other anti-oxidants. We further demonstrate that KLF15 deficiency in the cardiomyocytes in vitro and in vivo are both associated with increased mitochondrial acetylation, including MnSOD acetylation at Lysine 122, which leads to reduced MnSOD activity. There is no change in mitochondrial sirtuin SIRT3 level, the main deacetylase for mitochondrial acetylated proteins including MnSOD
K122
, however its co-enzyme NAD
+
level and NAD
+
/NADH ratio are drastically reduced with KLF15 deficiency. Furthermore, NAD
+
precursor NMN rescues the increased susceptibility to ROS in KLF15 deficient cardiomyocytes and I/R injury in vivo. Finally, we show that KLF15 directly regulates nicotinamide phosphoribosyltransferase (NAMPT), the rate limiting enzyme of NAD
+
salvage pathway and the main NAD
+
determinant in the heart. Collectively, our results demonstrate that KLF15 coordinates cardiac metabolism and ROS clearance in a circadian fashion through mitochondrial NAD
+
; loss of KLF15 expression in ischemic cardiomyopathy likely contributes to an enhanced susceptibility to additional I/R insult in a time-of-the-day dependent fashion.
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Affiliation(s)
- Le Li
- Baylor College of Medicine, houston, TX
| | - Hui Li
- Baylor College of Medicine, houston, TX
| | | | - Rongli Zhang
- Case Cardiovascular Rsch Institute, Dept of Medicine, Harrington Heart and Vascular Institute, Univ Hosps Cleveland Med Cntr, Cleveland, OH
| | - Xudong Liao
- Case Cardiovascular Rsch Institute, Dept of Medicine, Harrington Heart and Vascular Institute, Univ Hosps Cleveland Med Cntr, Cleveland, OH
| | - Mukesh K. Jain
- Case Cardiovascular Rsch Institute, Dept of Medicine, Harrington Heart and Vascular Institute, Univ Hosps Cleveland Med Cntr, Cleveland, OH
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6
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Meares GP, Rajbhandari R, Gerigk M, Tien CL, Chang C, Fehling SC, Rowse A, Mulhern KC, Nair S, Gray GK, Berbari NF, Bredel M, Benveniste EN, Nozell SE. MicroRNA-31 is required for astrocyte specification. Glia 2018; 66:987-998. [PMID: 29380422 DOI: 10.1002/glia.23296] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 10/30/2017] [Accepted: 01/08/2018] [Indexed: 12/21/2022]
Abstract
Previously, we determined microRNA-31 (miR-31) is a noncoding tumor suppressive gene frequently deleted in glioblastoma (GBM); miR-31 suppresses tumor growth, in part, by limiting the activity of NF-κB. Herein, we expand our previous studies by characterizing the role of miR-31 during neural precursor cell (NPC) to astrocyte differentiation. We demonstrate that miR-31 expression and activity is suppressed in NPCs by stem cell factors such as Lin28, c-Myc, SOX2 and Oct4. However, during astrocytogenesis, miR-31 is induced by STAT3 and SMAD1/5/8, which mediate astrocyte differentiation. We determined miR-31 is required for terminal astrocyte differentiation, and that the loss of miR-31 impairs this process and/or prevents astrocyte maturation. We demonstrate that miR-31 promotes astrocyte development, in part, by reducing the levels of Lin28, a stem cell factor implicated in NPC renewal. These data suggest that miR-31 deletions may disrupt astrocyte development and/or homeostasis.
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Affiliation(s)
- Gordon P Meares
- Departments of Microbiology, Immunology and Cell Biology, West Virginia University, Morgantown, West Virginia, 26506
| | - Rajani Rajbhandari
- Departments of Radiation Oncology, University of Alabama at Birmingham, Birmingham, Alabama, 35294
| | - Magda Gerigk
- Departments of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama, 35294
| | - Chih-Liang Tien
- Departments of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama, 35294
| | - Chenbei Chang
- Departments of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama, 35294
| | - Samuel C Fehling
- Departments of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama, 35294
| | - Amber Rowse
- Departments of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama, 35294
| | - Kayln C Mulhern
- Departments of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama, 35294
| | - Sindhu Nair
- Departments of Radiation Oncology, University of Alabama at Birmingham, Birmingham, Alabama, 35294
| | - G Kenneth Gray
- Departments of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama, 35294
| | - Nicolas F Berbari
- Departments of Biology, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana, 46202
| | - Markus Bredel
- Departments of Radiation Oncology, University of Alabama at Birmingham, Birmingham, Alabama, 35294
| | - Etty N Benveniste
- Departments of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama, 35294
| | - Susan E Nozell
- Departments of Radiation Oncology, University of Alabama at Birmingham, Birmingham, Alabama, 35294
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7
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Zhang L, Zhang R, Tien CL, Chan RE, Sugi K, Fu C, Griffin AC, Shen Y, Burris TP, Liao X, Jain MK. REV-ERBα ameliorates heart failure through transcription repression. JCI Insight 2017; 2:95177. [PMID: 28878135 DOI: 10.1172/jci.insight.95177] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Accepted: 08/03/2017] [Indexed: 12/20/2022] Open
Abstract
A cure for heart failure remains a major unmet clinical need, and current therapies targeting neurohomonal and hemodynamic regulation have limited efficacy. The pathological remodeling of the myocardium has been associated with a stereotypical gene expression program, which had long been viewed as the consequence and not the driver of the disease until very recently. Despite the advance, there is no therapy available to reverse the already committed gene program. Here, we demonstrate that transcriptional repressor REV-ERB binds near driver transcription factors across the genome. Pharmacological activation of REV-ERB selectively suppresses aberrant pathologic gene expression and prevents cardiomyocyte hypertrophy. In vivo, REV-ERBα activation prevents development of cardiac hypertrophy, reduces fibrosis, and halts progression of advanced heart failure in mouse models. Thus, to our knowledge, modulation of gene networks by targeting REV-ERBα represents a novel approach to heart failure therapy.
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Affiliation(s)
- Lilei Zhang
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.,Case Cardiovascular Research Institute, Department of Medicine, Harrington Heart and Vascular Institute
| | - Rongli Zhang
- Case Cardiovascular Research Institute, Department of Medicine, Harrington Heart and Vascular Institute
| | - Chih-Liang Tien
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
| | | | - Keiki Sugi
- Case Cardiovascular Research Institute, Department of Medicine, Harrington Heart and Vascular Institute
| | - Chen Fu
- Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, Ohio, USA
| | - Austin C Griffin
- Case Cardiovascular Research Institute, Department of Medicine, Harrington Heart and Vascular Institute
| | - Yuyan Shen
- Case Cardiovascular Research Institute, Department of Medicine, Harrington Heart and Vascular Institute
| | - Thomas P Burris
- Department of Pharmacology and Physiology, Saint Louis University, St. Louis, Missouri, USA
| | - Xudong Liao
- Case Cardiovascular Research Institute, Department of Medicine, Harrington Heart and Vascular Institute
| | - Mukesh K Jain
- Case Cardiovascular Research Institute, Department of Medicine, Harrington Heart and Vascular Institute
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8
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Tien CL, Jones A, Wang H, Gerigk M, Nozell S, Chang C. Snail2/Slug cooperates with Polycomb repressive complex 2 (PRC2) to regulate neural crest development. Development 2015; 142:722-31. [PMID: 25617436 DOI: 10.1242/dev.111997] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Neural crest cells arise from the border of the neural plate and epidermal ectoderm, migrate extensively and differentiate into diverse cell types during vertebrate embryogenesis. Although much has been learnt about growth factor signals and gene regulatory networks that regulate neural crest development, limited information is available on how epigenetic mechanisms control this process. In this study, we show that Polycomb repressive complex 2 (PRC2) cooperates with the transcription factor Snail2/Slug to modulate neural crest development in Xenopus. The PRC2 core components Eed, Ezh2 and Suz12 are expressed in the neural crest cells and are required for neural crest marker expression. Knockdown of Ezh2, the catalytic subunit of PRC2 for histone H3K27 methylation, results in defects in neural crest specification, migration and craniofacial cartilage formation. EZH2 interacts directly with Snail2, and Snail2 fails to expand the neural crest domains in the absence of Ezh2. Chromatin immunoprecipitation analysis shows that Snail2 regulates EZH2 occupancy and histone H3K27 trimethylation levels at the promoter region of the Snail2 target E-cadherin. Our results indicate that Snail2 cooperates with EZH2 and PRC2 to control expression of the genes important for neural crest specification and migration during neural crest development.
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Affiliation(s)
- Chih-Liang Tien
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, 1720 2nd Avenue S., Birmingham, AL 35294, USA
| | - Amanda Jones
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, 1720 2nd Avenue S., Birmingham, AL 35294, USA
| | - Hengbin Wang
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, 1720 2nd Avenue S., Birmingham, AL 35294, USA
| | - Magda Gerigk
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, 1720 2nd Avenue S., Birmingham, AL 35294, USA
| | - Susan Nozell
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, 1720 2nd Avenue S., Birmingham, AL 35294, USA
| | - Chenbei Chang
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, 1720 2nd Avenue S., Birmingham, AL 35294, USA
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9
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Tien CL, Lin CH, Lin TH, Wen FC, Su CW, Fan SS, Hsieh M. Secreted cyclophilin A induction during embryo implantation in a model of human trophoblast–endometrial epithelium interaction. Eur J Obstet Gynecol Reprod Biol 2012; 164:55-9. [DOI: 10.1016/j.ejogrb.2012.05.027] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2011] [Revised: 03/22/2012] [Accepted: 05/12/2012] [Indexed: 11/24/2022]
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10
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Tien CL, Wen FC, Hsieh M. The polyglutamine-expanded protein ataxin-3 decreases bcl-2 mRNA stability. Biochem Biophys Res Commun 2008; 365:232-8. [DOI: 10.1016/j.bbrc.2007.10.162] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2007] [Accepted: 10/23/2007] [Indexed: 11/27/2022]
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11
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Abstract
Silicon nitrides are synthesized by ion-assisted deposition with only one coating material and a nitrogen-ion-beam source. All the SiN(x) films are amorphous and mechanically strong. A wide range of refractive indices from 3.43 to 1.72 at a wavelength of 1550 nm is obtained. Near-IR antireflection coating and a bandpass filter based on the multilayers of SiN(x) and Si are demonstrated.
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Affiliation(s)
- C C Lee
- Institute of Optical Sciences, National Central University, Chung-Li 320, Taiwan.
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12
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13
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Suter U, Angst C, Tien CL, Drinkwater CC, Lindsay RM, Shooter EM. NGF/BDNF chimeric proteins: analysis of neurotrophin specificity by homolog-scanning mutagenesis. J Neurosci 1992; 12:306-18. [PMID: 1729439 PMCID: PMC6575690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Despite their extensive sequence identities at the amino acid level (approximately 55%), NGF and brain-derived neurotrophic factor (BDNF) display distinct neuronal specificity toward neurons of both the PNS and CNS. To explore which region(s) within these neurotrophic factors might determine their differential actions on various subpopulations of peripheral neurons, a systematic series (homolog-scanning mutagenesis) of chimeric NGF/BDNF molecules was prepared using PCR overlap-extension techniques. After expression in COS-7 cells, the chimeric proteins were tested for their biological activities in neurite outgrowth and neuronal survival assays. This approach led to the functional expression of 12 NGF/BDNF chimeras. Surprisingly, despite replacing successive amino acid segments throughout the entire length of NGF with the corresponding parts of BDNF, all chimeras displayed full NGF-like activity in bioassays carried out with PC12 cells, embryonic chick dorsal root ganglion explants, sympathetic ganglion explants, and dissociated cultures of dorsal root ganglion neurons. Most of the chimeras additionally showed BDNF-like activity as defined by neurite outgrowth on chick nodose ganglion explants. However, none of the chimeras supported the survival of dissociated nodose ganglion neurons. Our results suggest that NGF and BDNF must share very similar higher-order protein structures, and we propose that the overall structure or conformation of NGF, in contrast to short amino acid "active-site" segments, may determine its exact neuronal specificity.
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Affiliation(s)
- U Suter
- Department of Neurobiology, Stanford University School of Medicine, California 94305-5401
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14
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Chow LC, Tien CL. Inversion techniques for determining the droplet size distribution in clouds: numerical examination. Appl Opt 1976; 15:378-383. [PMID: 20164978 DOI: 10.1364/ao.15.000378] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The Phillips-Twomey and Backus-Gilbert inversion techniques are applied to determine the size distribution of water droplets in clouds from light scattering data at backward angles. The data are generated numerically from the Mie scattering functions and an assumed cloud model. The size distribution is recovered from these data using the two inversion techniques and is compared with the assumed model. It is found that the Phillips-Twomey technique gives better agreement between the assumed and recovered size distributions than the Backus-Gilbert technique. Also, it is more stable to random errors artificially introduced into the scattering data.
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15
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Tien CL. Atmospheric corrections for airborne measurements of water surface temperature. Appl Opt 1974; 13:1745-1746. [PMID: 20134551 DOI: 10.1364/ao.13.001745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
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