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Lehle JD, Lin YH, Gomez A, Chavez L, McCarrey JR. Endocrine disruptor-induced epimutagenesis in vitro : Insight into molecular mechanisms. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.05.574355. [PMID: 38746310 PMCID: PMC11092511 DOI: 10.1101/2024.01.05.574355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
Endocrine disrupting chemicals (EDCs) such as bisphenol S (BPS) are xenobiotic compounds that can disrupt endocrine signaling following exposure due to steric similarities to endogenous hormones within the body. EDCs have been shown to induce disruptions in normal epigenetic programming (epimutations) that accompany dysregulation of normal gene expression patterns that appear to predispose disease states. Most interestingly, the prevalence of epimutations following exposure to many different EDCs often persists over multiple subsequent generations, even with no further exposure to the causative EDC. Many previous studies have described both the direct and prolonged effects of EDC exposure in animal models, but many questions remain about molecular mechanisms by which EDCs initially induce epimutations or contribute to the propagation of EDC-induced epimutations either within the exposed generation or to subsequent generations. Additional questions remain regarding the extent to which there may be differences in cell-type specific susceptibilities to various EDCs, and whether this susceptibility is correlative with expression of relevant hormone receptors and/or the location of relevant hormone response elements (HREs) in the genome. To address these questions, we exposed cultured mouse pluripotent (induced pluripotent stem [iPS]), somatic (Sertoli and granulosa), and germ (primordial germ cell like [PGCLC]) cells to BPS and measured changes in DNA methylation levels at the epigenomic level and gene expression at the transcriptomic level. We found that there was indeed a difference in cell-type specific susceptibility to EDC-induced epimutagenesis and that this susceptibility correlated with differential expression of relevant hormone receptors and, in many cases, tended to generate epimutations near relevant HREs within the genome. Additionally, however, we also found that BPS can induce epimutations in a cell type that does not express relevant receptors and in genomic regions that do not contain relevant HREs, suggesting that both canonical and non-canonical signaling mechanisms can be disrupted by BPS exposure. Most interestingly, we found that when iPS cells were exposed to BPS and then induced to differentiate into PGCLCs, the prevalence of epimutations and differentially expressed genes (DEGs) initially induced in the iPSCs was largely retained in the resulting PGCLCs, however, >90% of the specific epimutations and DEGs were not conserved but were rather replaced by novel epimutations and DEGs following the iPSC to PGCLC transition. These results are consistent with a unique concept that many EDC-induced epimutations may normally be corrected by germline and/or embryonic epigenetic reprogramming but that due to disruption of the underlying chromatin architecture induced by the EDC exposure, many novel epimutations may emerge during the reprogramming process as well. Thus, it appears that following exposure to a disruptive agent such as an EDC, a prevalence of epimutations may transcend epigenetic reprogramming even though most individual epimutations are not conserved during this process.
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Deb P, Chini A, Guha P, Rishi A, Bhan A, Brady B, Perrotti LI, Mandal SS. Dynamic regulation of BDNF gene expression by estradiol and lncRNA HOTAIR. Gene 2024; 897:148055. [PMID: 38043834 DOI: 10.1016/j.gene.2023.148055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Revised: 11/22/2023] [Accepted: 11/29/2023] [Indexed: 12/05/2023]
Abstract
Brain derived neurotrophic factor (BDNF) is a major neurotransmitter that controls growth and maintenance of neurons and its misregulation is linked to neurodegeneration and human diseases. Estradiol (E2) is well-known to regulate the process of differentiation and plasticity of hippocampal neurons. Here we examined the mechanisms of BDNF gene regulation under basal conditions and under stimuli such as E2. Our results demonstrated that BDNF expression is induced by E2 in vitro in HT22 cells (hippocampal neuronal cells) and in vivo (in ovariectomized mouse brain under E2-treatment). Using chromatin immunoprecipitation assay, we demonstrated that estrogen receptors (ERα, ERβ) were enriched at the BDNF promoter in presence of E2. Additionally, ER-coregulators (e.g., CBP/p300, MLL3), histone acetylation, H3K4-trimethylation, and RNA polymerase II levels were also elevated at the BDNF promoter in an E2-dependent manner. Additionally, under the basal conditions (in the absence of E2), the long noncoding RNA HOTAIR and its interacting partners PRC2 and LSD1 complexes binds to the promoter of BDNF and represses its expression. HOTAIR knockdown -relieves the repression resulting in elevation of BDNF expression. Further, levels of HOTAIR-interacting partners, EZH2 and LSD1 were reduced at the BDNF promoter upon HOTAIR-knockdown revealing that HOTAIR plays a regulatory role in BDNF gene expression by modulating promoter histone modifications. Additionally, we showed that E2 induced-BDNF expression is mediated by the displacement of silencing factors, EZH2 and LSD1 at BDNF promoter and subsequent recruitment of active transcription machinery. These results reveal the mechanisms of BDNF gene regulation under the basal condition and in presence of a positive regulator such as E2 in neuronal cells.
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Affiliation(s)
- Paromita Deb
- Gene Regulation and Epigenetics Research Lab, Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, TX 76019, United States
| | - Avisankar Chini
- Gene Regulation and Epigenetics Research Lab, Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, TX 76019, United States
| | - Prarthana Guha
- Gene Regulation and Epigenetics Research Lab, Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, TX 76019, United States
| | - Ashcharya Rishi
- Gene Regulation and Epigenetics Research Lab, Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, TX 76019, United States
| | - Arunoday Bhan
- Gene Regulation and Epigenetics Research Lab, Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, TX 76019, United States
| | - Blake Brady
- Department of Psychology, The University of Texas at Arlington, Arlington, TX 76019, United States
| | - Linda I Perrotti
- Department of Psychology, The University of Texas at Arlington, Arlington, TX 76019, United States
| | - Subhrangsu S Mandal
- Gene Regulation and Epigenetics Research Lab, Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, TX 76019, United States.
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3
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Alkailani MI, Gibbings D. The Regulation and Immune Signature of Retrotransposons in Cancer. Cancers (Basel) 2023; 15:4340. [PMID: 37686616 PMCID: PMC10486412 DOI: 10.3390/cancers15174340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Revised: 08/14/2023] [Accepted: 08/18/2023] [Indexed: 09/10/2023] Open
Abstract
Advances in sequencing technologies and the bioinformatic analysis of big data facilitate the study of jumping genes' activity in the human genome in cancer from a broad perspective. Retrotransposons, which move from one genomic site to another by a copy-and-paste mechanism, are regulated by various molecular pathways that may be disrupted during tumorigenesis. Active retrotransposons can stimulate type I IFN responses. Although accumulated evidence suggests that retrotransposons can induce inflammation, the research investigating the exact mechanism of triggering these responses is ongoing. Understanding these mechanisms could improve the therapeutic management of cancer through the use of retrotransposon-induced inflammation as a tool to instigate immune responses to tumors.
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Affiliation(s)
- Maisa I. Alkailani
- College of Health and Life Sciences, Hamad Bin Khalifa University, Qatar Foundation, Doha P.O. Box 34110, Qatar
| | - Derrick Gibbings
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada;
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Stenz L, Beyens M, Gill ME, Paoloni-Giacobino A, De Geyter C. Altered DNA methylation in estrogen-responsive repetitive sequences of spermatozoa of infertile men with shortened anogenital distance. Clin Epigenetics 2022; 14:185. [PMID: 36572941 PMCID: PMC9793642 DOI: 10.1186/s13148-022-01409-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Accepted: 12/14/2022] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND It has been suggested that antenatal exposure to environmental endocrine disruptors is responsible for adverse trends in male reproductive health, including male infertility, impaired semen quality, cryptorchidism and testicular cancer, a condition known as testicular dysgenesis syndrome. Anogenital distance (AGD) is an anthropomorphic measure of antenatal exposure to endocrine disruptors, with higher exposure levels leading to shortened AGD. We hypothesized that exposure to endocrine disruptors could lead to changes in DNA methylation during early embryonic development, which could then persist in the sperm of infertile men with shortened AGD. RESULTS Using fluorescence activated cell sorting based on staining with either YO-PRO-1 (YOPRO) or chromomycin-3 (CMA3), we isolated four sperm fractions from eleven infertile men with short AGD and ten healthy semen donors. We examined DNA methylation in these sorted spermatozoa using reduced representation bisulfite sequencing. We found that fractions of spermatozoa from infertile men stained with CMA3 or YOPRO were more likely to contain transposable elements harboring an estrogen receptor response element (ERE). Abnormal sperm (as judged by high CMA3 or YOPRO staining) from infertile men shows substantial hypomethylation in estrogenic Alu sequences. Conversely, normal sperm fractions (as judged by low CMA3 or YO-PRO-1 staining) of either healthy donors or infertile patients were more likely to contain hypermethylated Alu sequences with ERE. CONCLUSIONS Shortened AGD, as related to previous exposure to endocrine disruptors, and male infertility are accompanied by increased presence of hormonal response elements in the differentially methylated regulatory sequences of the genome of sperm fractions characterized by chromatin decondensation and apoptosis.
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Affiliation(s)
- Ludwig Stenz
- grid.8591.50000 0001 2322 4988Department of Genetic Medicine and Development, Faculty of Medicine, University of Geneva, Rue Michel-Servet, 1, 1211 Geneva, Switzerland ,Swiss Centre for Applied Human Toxicology (SCAHT), Missionsstrasse, 64, 4055 Basel, Switzerland
| | - Matthias Beyens
- BISC Global, Bioinformatics and Statistics Consulting, Gaston Crommenlaan, 8, 9050 Ghent, Belgium
| | - Mark E. Gill
- grid.6612.30000 0004 1937 0642Reproductive Medicine and Gynecological Endocrinology (RME), University Hospital, University of Basel, Vogesenstrasse, 134, 4031 Basel, Switzerland
| | - Ariane Paoloni-Giacobino
- grid.8591.50000 0001 2322 4988Department of Genetic Medicine and Development, Faculty of Medicine, University of Geneva, Rue Michel-Servet, 1, 1211 Geneva, Switzerland ,Swiss Centre for Applied Human Toxicology (SCAHT), Missionsstrasse, 64, 4055 Basel, Switzerland
| | - Christian De Geyter
- Swiss Centre for Applied Human Toxicology (SCAHT), Missionsstrasse, 64, 4055 Basel, Switzerland ,grid.6612.30000 0004 1937 0642Reproductive Medicine and Gynecological Endocrinology (RME), University Hospital, University of Basel, Vogesenstrasse, 134, 4031 Basel, Switzerland
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Chiang VSC, DeRosa H, Park JH, Hunter RG. The Role of Transposable Elements in Sexual Development. Front Behav Neurosci 2022; 16:923732. [PMID: 35874645 PMCID: PMC9301316 DOI: 10.3389/fnbeh.2022.923732] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Accepted: 06/20/2022] [Indexed: 11/19/2022] Open
Abstract
Up to 50% of most mammalian genomes are made up of transposable elements (TEs) that have the potential to mobilize around the genome. Despite this prevalence, research on TEs is only beginning to gain traction within the field of neuroscience. While TEs have long been regarded as “junk” or parasitic DNA, it has become evident that they are adaptive DNA and RNA regulatory elements. In addition to their vital role in normal development, TEs can also interact with steroid receptors, which are key elements to sexual development. In this review, we provide an overview of the involvement of TEs in processes related to sexual development- from TE activity in the germline to TE accumulation in sex chromosomes. Moreover, we highlight sex differences in TE activity and their regulation of genes related to sexual development. Finally, we speculate on the epigenetic mechanisms that may govern TEs’ role in sexual development. In this context, we emphasize the need to further the understanding of sexual development through the lens of TEs including in a variety of organs at different developmental stages, their molecular networks, and evolution.
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Datta RR, Rister J. The power of the (imperfect) palindrome: Sequence-specific roles of palindromic motifs in gene regulation. Bioessays 2022; 44:e2100191. [PMID: 35195290 PMCID: PMC8957550 DOI: 10.1002/bies.202100191] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 02/01/2022] [Accepted: 02/03/2022] [Indexed: 12/22/2022]
Abstract
In human languages, a palindrome reads the same forward as backward (e.g., 'madam'). In regulatory DNA, a palindrome is an inverted sequence repeat that allows a transcription factor to bind as a homodimer or as a heterodimer with another type of transcription factor. Regulatory palindromes are typically imperfect, that is, the repeated sequences differ in at least one base pair, but the functional significance of this asymmetry remains poorly understood. Here, we review the use of imperfect palindromes in Drosophila photoreceptor differentiation and mammalian steroid receptor signaling. Moreover, we discuss mechanistic explanations for the predominance of imperfect palindromes over perfect palindromes in these two gene regulatory contexts. Lastly, we propose to elucidate whether specific imperfectly palindromic variants have specific regulatory functions in steroid receptor signaling and whether such variants can help predict transcriptional outcomes as well as the response of individual patients to drug treatments.
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Affiliation(s)
- Rhea R Datta
- Department of Biology, Hamilton College, Clinton, New York, USA
| | - Jens Rister
- Department of Biology, University of Massachusetts Boston, Integrated Sciences Complex, Boston, Massachusetts, USA
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7
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Altwegg KA, Vadlamudi RK. Role of estrogen receptor coregulators in endocrine resistant breast cancer. EXPLORATION OF TARGETED ANTI-TUMOR THERAPY 2021; 2:385-400. [PMID: 34528025 PMCID: PMC8439438 DOI: 10.37349/etat.2021.00052] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Breast cancer (BC) is the most ubiquitous cancer in women. Approximately 70–80% of BC diagnoses are positive for estrogen receptor (ER) alpha (ERα). The steroid hormone estrogen [17β-estradiol (E2)] plays a vital role both in the initiation and progression of BC. The E2-ERα mediated actions involve genomic signaling and non-genomic signaling. The specificity and magnitude of ERα signaling are mediated by interactions between ERα and several coregulator proteins called coactivators or corepressors. Alterations in the levels of coregulators are common during BC progression and they enhance ligand-dependent and ligand-independent ERα signaling which drives BC growth, progression, and endocrine therapy resistance. Many ERα coregulator proteins function as scaffolding proteins and some have intrinsic or associated enzymatic activities, thus the targeting of coregulators for blocking BC progression is a challenging task. Emerging data from in vitro and in vivo studies suggest that targeting coregulators to inhibit BC progression to therapy resistance is feasible. This review explores the current state of ERα coregulator signaling and the utility of targeting the ERα coregulator axis in treating advanced BC.
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Affiliation(s)
- Kristin A Altwegg
- Department of Obstetrics and Gynecology, University of Texas Health San Antonio, San Antonio, TX 78229, USA.,Mays Cancer Center, University of Texas Health San Antonio, San Antonio, TX 78229, USA
| | - Ratna K Vadlamudi
- Department of Obstetrics and Gynecology, University of Texas Health San Antonio, San Antonio, TX 78229, USA.,Mays Cancer Center, University of Texas Health San Antonio, San Antonio, TX 78229, USA
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8
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Ren J, Tian W, Jiang K, Wang Z, Wang D, Li Z, Yan F, Wang Y, Tian Y, Ou K, Wang H, Kang X, Li H, Liu X. Global investigation of estrogen-responsive genes regulating lipid metabolism in the liver of laying hens. BMC Genomics 2021; 22:428. [PMID: 34107898 PMCID: PMC8190866 DOI: 10.1186/s12864-021-07679-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 05/05/2021] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND Estrogen plays an essential role in female development and reproductive function. In chickens, estrogen is critical for lipid metabolism in the liver. The regulatory molecular network of estrogen in chicken liver is poorly understood. To identify estrogen-responsive genes and estrogen functional sites on a genome-wide scale, we determined expression profiles of mRNAs, lncRNAs, and miRNAs in estrogen-treated ((17β-estradiol)) and control chicken livers using RNA-Sequencing (RNA-Seq) and studied the estrogen receptor α binding sites by ChIP-Sequencing (ChIP-Seq). RESULTS We identified a total of 990 estrogen-responsive genes, including 962 protein-coding genes, 11 miRNAs, and 17 lncRNAs. Functional enrichment analyses showed that the estrogen-responsive genes were highly enriched in lipid metabolism and biological processes. Integrated analysis of the data of RNA-Seq and ChIP-Seq, identified 191 genes directly targeted by estrogen, including 185 protein-coding genes, 4 miRNAs, and 2 lncRNAs. In vivo and in vitro experiments showed that estrogen decreased the mRNA expression of PPARGC1B, which had been reported to be linked with lipid metabolism, by directly increasing the expression of miR-144-3p. CONCLUSIONS These results increase our understanding of the functional network of estrogen in chicken liver and also reveal aspects of the molecular mechanism of estrogen-related lipid metabolism.
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Affiliation(s)
- Junxiao Ren
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, China
| | - Weihua Tian
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, China
| | - Keren Jiang
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, China
| | - Zhang Wang
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, China
| | - Dandan Wang
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, China.,Henan Innovative Engineering Research Center of Poultry Germplasm Resource, Henan Agricultural University, Zhengzhou, 450002, China.,International Joint Research Laboratory for Poultry Breeding of Henan, Henan Agricultural University, Zhengzhou, 450002, China
| | - Zhuanjian Li
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, China.,Henan Innovative Engineering Research Center of Poultry Germplasm Resource, Henan Agricultural University, Zhengzhou, 450002, China.,International Joint Research Laboratory for Poultry Breeding of Henan, Henan Agricultural University, Zhengzhou, 450002, China
| | - Fengbin Yan
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, China.,Henan Innovative Engineering Research Center of Poultry Germplasm Resource, Henan Agricultural University, Zhengzhou, 450002, China.,International Joint Research Laboratory for Poultry Breeding of Henan, Henan Agricultural University, Zhengzhou, 450002, China
| | - Yanbin Wang
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, China.,Henan Innovative Engineering Research Center of Poultry Germplasm Resource, Henan Agricultural University, Zhengzhou, 450002, China.,International Joint Research Laboratory for Poultry Breeding of Henan, Henan Agricultural University, Zhengzhou, 450002, China
| | - Yadong Tian
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, China.,Henan Innovative Engineering Research Center of Poultry Germplasm Resource, Henan Agricultural University, Zhengzhou, 450002, China.,International Joint Research Laboratory for Poultry Breeding of Henan, Henan Agricultural University, Zhengzhou, 450002, China
| | - Kepeng Ou
- College of Pharmacy, National and Local Joint Engineering Research Center of Targeted and Innovative Therapeutics, Chongqing Key Laboratory of Kinase Modulators as Innovative Medicine, Chongqing University of Arts and Sciences, Chongqing, China
| | - Hongjun Wang
- Center for Cellular Therapy, Medical University of South Carolina, Charleston, SC, 29425, USA
| | - Xiangtao Kang
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, China.,Henan Innovative Engineering Research Center of Poultry Germplasm Resource, Henan Agricultural University, Zhengzhou, 450002, China.,International Joint Research Laboratory for Poultry Breeding of Henan, Henan Agricultural University, Zhengzhou, 450002, China
| | - Hong Li
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, China. .,Henan Innovative Engineering Research Center of Poultry Germplasm Resource, Henan Agricultural University, Zhengzhou, 450002, China. .,International Joint Research Laboratory for Poultry Breeding of Henan, Henan Agricultural University, Zhengzhou, 450002, China.
| | - Xiaojun Liu
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, China. .,Henan Innovative Engineering Research Center of Poultry Germplasm Resource, Henan Agricultural University, Zhengzhou, 450002, China. .,International Joint Research Laboratory for Poultry Breeding of Henan, Henan Agricultural University, Zhengzhou, 450002, China.
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9
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Alderman MH, Taylor HS. Molecular mechanisms of estrogen action in female genital tract development. Differentiation 2021; 118:34-40. [PMID: 33707128 DOI: 10.1016/j.diff.2021.01.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Revised: 12/29/2020] [Accepted: 01/04/2021] [Indexed: 10/22/2022]
Abstract
The development of the female reproductive tract can be divided into three parts consisting of Müllerian duct organogenesis, pre-sexual maturation organ development, and post-sexual maturation hormonal regulation. In primates, Müllerian duct organogenesis proceeds in an estrogen independent fashion based on transcriptional pathways that are suppressed in males by the presence of AMH and SRY. However, clinical experience indicates that exposure to xenoestrogens such as diethylstilbestrol (DES) during critical periods including late organogenesis and pre-sexual maturational development can have substantial effects on uterine morphology, and confer increased risk of disease states later in life. Recent evidence has demonstrated that these effects are in part due to epigenetic regulation of gene expression, both in the form of aberrant CpG methylation, and accompanying histone modifications. While xenoestrogens and selective estrogen receptor modulators (SERMS) both can induce non-canonical binding confirmations in estrogen receptors, the primate specific fetal estrogens Estriol and Estetrol may act in a similar fashion to alter gene expression through tissue specific epigenetic modulation.
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Affiliation(s)
- Myles H Alderman
- Department of Obstetrics, Gynecology and Reproductive Sciences, Yale School of Medicine, New Haven, CT, 06520, USA; Yale Stem Cell Center, Yale School of Medicine, New Haven, CT, 06520, USA
| | - Hugh S Taylor
- Department of Obstetrics, Gynecology and Reproductive Sciences, Yale School of Medicine, New Haven, CT, 06520, USA.
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10
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Estrogen Induces Selective Transcription of Caveolin1 Variants in Human Breast Cancer through Estrogen Responsive Element-Dependent Mechanisms. Int J Mol Sci 2020; 21:ijms21175989. [PMID: 32825330 PMCID: PMC7503496 DOI: 10.3390/ijms21175989] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 08/13/2020] [Accepted: 08/19/2020] [Indexed: 02/07/2023] Open
Abstract
The estrogen receptor (ER) signaling regulates numerous physiological processes mainly through activation of gene transcription (genomic pathways). Caveolin1 (CAV1) is a membrane-resident protein that behaves as platform to enable different signaling molecules and receptors for membrane-initiated pathways. CAV1 directly interacts with ERs and allows their localization on membrane with consequent activation of ER-non-genomic pathways. Loss of CAV1 function is a common feature of different types of cancers, including breast cancer. Two protein isoforms, CAV1α and CAV1β, derived from two alternative translation initiation sites, are commonly described for this gene. However, the exact transcriptional regulation underlying CAV1 expression pattern is poorly elucidated. In this study, we dissect the molecular mechanism involved in selective expression of CAV1β isoform, induced by estrogens and downregulated in breast cancer. Luciferase assays and Chromatin immunoprecipitation demonstrate that transcriptional activation is triggered by estrogen-responsive elements embedded in CAV1 intragenic regions and DNA-binding of estrogen-ER complexes. This regulatory control is dynamically established by local chromatin changes, as proved by the occurrence of histone H3 methylation/demethylation events and association of modifier proteins as well as modification of H3 acetylation status. Thus, we demonstrate for the first time, an estrogen-ERs-dependent regulatory circuit sustaining selective CAV1β expression.
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11
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Sampathkumar NK, Bravo JI, Chen Y, Danthi PS, Donahue EK, Lai RW, Lu R, Randall LT, Vinson N, Benayoun BA. Widespread sex dimorphism in aging and age-related diseases. Hum Genet 2020; 139:333-356. [PMID: 31677133 PMCID: PMC7031050 DOI: 10.1007/s00439-019-02082-w] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2019] [Accepted: 10/26/2019] [Indexed: 02/07/2023]
Abstract
Although aging is a conserved phenomenon across evolutionary distant species, aspects of the aging process have been found to differ between males and females of the same species. Indeed, observations across mammalian studies have revealed the existence of longevity and health disparities between sexes, including in humans (i.e. with a female or male advantage). However, the underlying mechanisms for these sex differences in health and lifespan remain poorly understood, and it is unclear which aspects of this dimorphism stem from hormonal differences (i.e. predominance of estrogens vs. androgens) or from karyotypic differences (i.e. XX vs. XY sex chromosome complement). In this review, we discuss the state of the knowledge in terms of sex dimorphism in various aspects of aging and in human age-related diseases. Where the interplay between sex differences and age-related differences has not been explored fully, we present the state of the field to highlight important future research directions. We also discuss various dietary, drug or genetic interventions that were shown to improve longevity in a sex-dimorphic fashion. Finally, emerging tools and models that can be leveraged to decipher the mechanisms underlying sex differences in aging are also briefly discussed.
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Affiliation(s)
- Nirmal K Sampathkumar
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA, 90089, USA
- Maurice Wohl Clinical Neuroscience Institute, King's College London, London, UK
| | - Juan I Bravo
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA, 90089, USA
- Graduate Program in the Biology of Aging, University of Southern California, Los Angeles, CA, 90089, USA
| | - Yilin Chen
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA, 90089, USA
- Masters Program in Nutrition, Healthspan, and Longevity, University of Southern California, Los Angeles, CA, 90089, USA
| | - Prakroothi S Danthi
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA, 90089, USA
| | - Erin K Donahue
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA, 90089, USA
- Neuroscience Graduate Program, University of Southern California, Los Angeles, CA, 90089, USA
| | - Rochelle W Lai
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA, 90089, USA
| | - Ryan Lu
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA, 90089, USA
- Graduate Program in the Biology of Aging, University of Southern California, Los Angeles, CA, 90089, USA
| | - Lewis T Randall
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA, 90089, USA
- Graduate Program in the Biology of Aging, University of Southern California, Los Angeles, CA, 90089, USA
| | - Nika Vinson
- Department of Urology, Pelvic Medicine and Reconstructive Surgery, UCLA David Geffen School of Medicine, Los Angeles, CA, 90024, USA
| | - Bérénice A Benayoun
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA, 90089, USA.
- USC Norris Comprehensive Cancer Center, Epigenetics and Gene Regulation, Los Angeles, CA, 90089, USA.
- USC Stem Cell Initiative, Los Angeles, CA, 90089, USA.
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12
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Jones BG, Sealy RE, Penkert RR, Surman SL, Birshtein BK, Xu B, Neale G, Maul RW, Gearhart PJ, Hurwitz JL. From Influenza Virus Infections to Lupus: Synchronous Estrogen Receptor α and RNA Polymerase II Binding Within the Immunoglobulin Heavy Chain Locus. Viral Immunol 2020; 33:307-315. [PMID: 32105583 DOI: 10.1089/vim.2019.0144] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Males and females respond to pathogens differently and exhibit significantly different frequencies of autoimmune disease. For example, vaccinated adult females control influenza virus better than males, but females suffer systemic lupus erythematosus at a 9:1 frequency compared to males. Numerous explanations have been offered for these sex differences, but most have involved indirect mechanisms by which estrogen, a nuclear hormone, modifies cell barriers or immunity. In search of a direct mechanism, we examined the binding of estrogen receptor α (ERα), a class I nuclear hormone receptor, to the immunoglobulin heavy chain locus. Here, we show that in purified murine B cells, ERα and RNA polymerase II (RNA Pol II) exhibit extraordinarily similar DNA binding patterns. We further demonstrate that ERα preferentially binds adenosine-cytidine (AC)-repeats in the immunoglobulin heavy chain locus when supplemental estrogen is added to purified, lipopolysaccharide-activated B cells. Based on these and previous data, we hypothesize that (i) estrogen guides the binding of ERα and its RNA Pol II partner within the locus, which in turn instructs sterile transcription and class switch recombination (CSR), (ii) ERα binding to AC-repeats modifies the DNA architecture and loops associated with CSR, and (iii) by these mechanisms, estrogen instructs antibody expression. By targeting ERα-DNA interactions in the immunoglobulin heavy chain locus, clinicians may ultimately enhance antibody responses in the context of infectious diseases and reduce antibody responses in the context of allergic or autoimmune reactions.
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Affiliation(s)
- Bart G Jones
- Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Robert E Sealy
- Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Rhiannon R Penkert
- Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Sherri L Surman
- Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Barbara K Birshtein
- Department of Cell Biology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Beisi Xu
- Department of Computational Biology, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Geoffrey Neale
- Hartwell Center for Bioinformatics and Biotechnology, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Robert W Maul
- National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA
| | - Patricia J Gearhart
- National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA
| | - Julia L Hurwitz
- Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, Tennessee, USA.,Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, Tennessee, USA
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13
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Cox RM. Sex steroids as mediators of phenotypic integration, genetic correlations, and evolutionary transitions. Mol Cell Endocrinol 2020; 502:110668. [PMID: 31821857 DOI: 10.1016/j.mce.2019.110668] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2019] [Revised: 11/19/2019] [Accepted: 11/26/2019] [Indexed: 02/06/2023]
Abstract
In recent decades, endocrinologists have increasingly adopted evolutionary methods and perspectives to characterize the evolution of the vertebrate endocrine system and leverage it as a model for developing and testing evolutionary theories. This review summarizes recent research on sex steroids (androgens and estrogens) to illustrate three ways in which a detailed understanding of the molecular and cellular architecture of hormonally mediated gene expression can enhance our understanding of general evolutionary principles. By virtue of their massively pleiotropic effects on the expression of genes and phenotypes, sex steroids and their receptors can (1) structure the patterns of phenotypic variance and covariance that are available to natural selection, (2) alter the underlying genetic correlations that determine a population's evolutionary response to selection, and (3) facilitate evolutionary transitions in fitness-related phenotypes via subtle regulatory shifts in underlying tissues and genes. These principles are illustrated by the author's research on testosterone and sexual dimorphism in lizards, and by recent examples drawn from other vertebrate systems. Mechanistically, these examples call attention to the importance of evolutionary changes in (1) androgen- and estrogen-mediated gene expression, (2) androgen and estrogen receptor expression, and (3) the distribution of androgen and estrogen response elements in target genes throughout the genome. A central theme to emerge from this review is that the rapidly increasing availability of genomic and transcriptomic data from non-model organisms places evolutionary endocrinologist in an excellent position to address the hormonal regulation of the key evolutionary interface between genes and phenotypes.
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Affiliation(s)
- Robert M Cox
- Department of Biology, University of Virginia, Charlottesville, VA, 22904, USA.
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14
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Jones BG, Sealy RE, Penkert RR, Surman SL, Maul RW, Neale G, Xu B, Gearhart PJ, Hurwitz JL. Complex sex-biased antibody responses: estrogen receptors bind estrogen response elements centered within immunoglobulin heavy chain gene enhancers. Int Immunol 2020; 31:141-156. [PMID: 30407507 DOI: 10.1093/intimm/dxy074] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2018] [Accepted: 11/02/2018] [Indexed: 01/10/2023] Open
Abstract
Nuclear hormone receptors including the estrogen receptor (ERα) and the retinoic acid receptor regulate a plethora of biological functions including reproduction, circulation and immunity. To understand how estrogen and other nuclear hormones influence antibody production, we characterized total serum antibody isotypes in female and male mice of C57BL/6J, BALB/cJ and C3H/HeJ mouse strains. Antibody levels were higher in females compared to males in all strains and there was a female preference for IgG2b production. Sex-biased patterns were influenced by vitamin levels, and by antigen specificity toward influenza virus or pneumococcus antigens. To help explain sex biases, we examined the direct effects of estrogen on immunoglobulin heavy chain sterile transcript production among purified, lipopolysaccharide-stimulated B cells. Supplemental estrogen in B-cell cultures significantly increased immunoglobulin heavy chain sterile transcripts. Chromatin immunoprecipitation analyses of activated B cells identified significant ERα binding to estrogen response elements (EREs) centered within enhancer elements of the immunoglobulin heavy chain locus, including the Eµ enhancer and hypersensitive site 1,2 (HS1,2) in the 3' regulatory region. The ERE in HS1,2 was conserved across animal species, and in humans marked a site of polymorphism associated with the estrogen-augmented autoimmune disease, lupus. Taken together, the results highlight: (i) the important targets of ERα in regulatory regions of the immunoglobulin heavy chain locus that influence antibody production, and (ii) the complexity of mechanisms by which estrogen instructs sex-biased antibody production profiles.
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Affiliation(s)
- Bart G Jones
- Department of Infectious Diseases, St. Jude Children's Research Hospital, Danny Thomas Place, Memphis, USA
| | - Robert E Sealy
- Department of Infectious Diseases, St. Jude Children's Research Hospital, Danny Thomas Place, Memphis, USA
| | - Rhiannon R Penkert
- Department of Infectious Diseases, St. Jude Children's Research Hospital, Danny Thomas Place, Memphis, USA
| | - Sherri L Surman
- Department of Infectious Diseases, St. Jude Children's Research Hospital, Danny Thomas Place, Memphis, USA
| | - Robert W Maul
- Laboratory of Molecular Biology and Immunology, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
| | - Geoff Neale
- Hartwell Center for Bioinformatics & Biotechnology, St. Jude Children's Research Hospital, Memphis, USA
| | - Beisi Xu
- Computational Biology, St. Jude Children's Research Hospital, Memphis, USA
| | - Patricia J Gearhart
- Laboratory of Molecular Biology and Immunology, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
| | - Julia L Hurwitz
- Department of Infectious Diseases, St. Jude Children's Research Hospital, Danny Thomas Place, Memphis, USA.,Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, USA
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15
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Euteneuer AM, Seeger‐Nukpezah T, Nolte H, Henjakovic M. Estrogen receptor α (ERα) indirectly induces transcription of human renal organic anion transporter 1 (OAT1). Physiol Rep 2019; 7:e14229. [PMID: 31724834 PMCID: PMC6854606 DOI: 10.14814/phy2.14229] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Accepted: 08/20/2019] [Indexed: 01/05/2023] Open
Abstract
Organic anion transporter 1 (OAT1) is a polyspecific transport protein located in the basolateral membrane of renal proximal tubule cells. OAT1 plays a pivotal role in drug clearance. Adverse drug reactions (ADR) are observed more frequently in women than in men, especially ADR are higher in women for drugs which are known interactors of OAT1. Sex-dependent expression of Oat1 has been observed in rodents with a tendency to male-dominant expression. This study aims at elucidating the transcriptional regulation of human OAT1 and tests the effect of estrogen receptor α (ERα). Promoter activation of OAT1 was assessed by luciferase assays carried out by Opossum kidney (OK) cells, transiently transfected with promoter constructs of human OAT1 and expression vectors for ERα and exposed to 100 nmol/L 17β-estradiol. Furthermore, a transcription factor array and proteomic analysis was performed to identify estrogen-induced transcription factors. Human OAT1 was significantly activated by ligand activated ERα. However, activation occurred without a direct interaction of ERα with the OAT1 promoter. Our data rather show an activation of the transcription factors CCAAT-box-binding transcription factor (CBF) and heterogeneous nuclear ribonucleoprotein K (HNRNPK) by ERα, which in turn bind and initiate OAT1 promoter activity. Herewith, we provide novel evidence of estrogen-dependent, transcriptional regulation of polyspecific drug transporters including the estrogen-induced transcription factors CBF and HNRNPK.
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Affiliation(s)
- Anna M. Euteneuer
- Department I of Internal Medicine and Center for Integrated OncologyUniversity of CologneCologneGermany
| | - Tamina Seeger‐Nukpezah
- Department I of Internal Medicine and Center for Integrated OncologyUniversity of CologneCologneGermany
| | - Hendrik Nolte
- Institute of Genetics and Cologne Excellence Cluster on Cellular Stress Responses in Aging‐Associated Diseases (CECAD)University of CologneCologneGermany
| | - Maja Henjakovic
- Department I of Internal Medicine and Center for Integrated OncologyUniversity of CologneCologneGermany
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16
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Cuesta R, Gritsenko MA, Petyuk VA, Shukla AK, Tsai CF, Liu T, McDermott JE, Holz MK. Phosphoproteome Analysis Reveals Estrogen-ER Pathway as a Modulator of mTOR Activity Via DEPTOR. Mol Cell Proteomics 2019; 18:1607-1618. [PMID: 31189691 PMCID: PMC6683011 DOI: 10.1074/mcp.ra119.001506] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 05/22/2019] [Indexed: 12/14/2022] Open
Abstract
ER-positive breast tumors represent ∼70% of all breast cancer cases. Although their treatment with endocrine therapies is effective in the adjuvant or recurrent settings, the development of resistance compromises their effectiveness. The binding of estrogen to ERα, a transcription factor, triggers the regulation of the target genes (genomic pathway). Additionally, a cytoplasmic fraction of estrogen-bound ERα activates oncogenic signaling pathways such as PI3K/AKT/mTOR (nongenomic pathway). The upregulation of the estrogenic and the PI3K/AKT/mTOR signaling pathways are frequently associated with a poor outcome. To better characterize the connection between these two pathways, we performed a phosphoproteome analysis of ER-positive MCF7 breast cancer cells treated with estrogen or estrogen and the mTORC1 inhibitor rapamycin. Many proteins were identified as estrogen-regulated mTORC1 targets and among them, DEPTOR was selected for further characterization. DEPTOR binds to mTOR and inhibits the kinase activity of both mTOR complexes mTORC1 and mTORC2, but mitogen-activated mTOR promotes phosphorylation-mediated DEPTOR degradation. Although estrogen enhances the phosphorylation of DEPTOR by mTORC1, DEPTOR levels increase in estrogen-stimulated cells. We demonstrated that DEPTOR accumulation is the result of estrogen-ERα-mediated transcriptional upregulation of DEPTOR expression. Consequently, the elevated levels of DEPTOR partially counterbalance the estrogen-induced activation of mTORC1 and mTORC2. These results underscore the critical role of estrogen-ERα as a modulator of the PI3K/AKT/mTOR signaling pathway in ER-positive breast cancer cells. Additionally, these studies provide evidence supporting the use of dual PI3K/mTOR or dual mTORC1/2 inhibitors in combination with endocrine therapies as a first-line treatment option for the patients with ER-positive advanced breast cancer.
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Affiliation(s)
- Rafael Cuesta
- Department of Cell Biology and Anatomy, New York Medical College, Valhalla NY 10595
| | - Marina A Gritsenko
- §Biological Sciences Division, Pacific Northwest National Laboratory, Richland WA 99352
| | - Vladislav A Petyuk
- §Biological Sciences Division, Pacific Northwest National Laboratory, Richland WA 99352
| | - Anil K Shukla
- §Biological Sciences Division, Pacific Northwest National Laboratory, Richland WA 99352
| | - Chia-Feng Tsai
- §Biological Sciences Division, Pacific Northwest National Laboratory, Richland WA 99352
| | - Tao Liu
- §Biological Sciences Division, Pacific Northwest National Laboratory, Richland WA 99352
| | - Jason E McDermott
- ¶Computational Biology and Bioinformatics Group, Pacific Northwest National Laboratory, Richland WA 99352
| | - Marina K Holz
- Department of Cell Biology and Anatomy, New York Medical College, Valhalla NY 10595; ‖Albert Einstein Cancer Center, Bronx NY 10461.
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17
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Sealy RE, Jones BG, Surman SL, Penkert RR, Pelletier S, Neale G, Hurwitz JL. Will Attention by Vaccine Developers to the Host's Nuclear Hormone Levels and Immunocompetence Improve Vaccine Success? Vaccines (Basel) 2019; 7:vaccines7010026. [PMID: 30818795 PMCID: PMC6466149 DOI: 10.3390/vaccines7010026] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 02/16/2019] [Accepted: 02/21/2019] [Indexed: 01/18/2023] Open
Abstract
Despite extraordinary advances in fields of immunology and infectious diseases, vaccine development remains a challenge. The development of a respiratory syncytial virus vaccine, for example, has spanned more than 50 years of research with studies of more than 100 vaccine candidates. Dozens of attractive vaccine products have entered clinical trials, but none have completed the path to licensing. Human immunodeficiency virus vaccine development has proven equally difficult, as there is no licensed product after more than 30 years of pre-clinical and clinical research. Here, we examine vaccine development with attention to the host. We discuss how nuclear hormones, including vitamins and sex hormones, can influence responses to vaccines. We show how nuclear hormones interact with regulatory elements of immunoglobulin gene loci and how the deletion of estrogen response elements from gene enhancers will alter patterns of antibody isotype expression. Based on these findings, and findings that nuclear hormone levels are often insufficient or deficient among individuals in both developed and developing countries, we suggest that failed vaccine studies may in some cases reflect weaknesses of the host rather than the product. We encourage analyses of nuclear hormone levels and immunocompetence among study participants in clinical trials to ensure the success of future vaccine programs.
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Affiliation(s)
- Robert E Sealy
- Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
| | - Bart G Jones
- Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
| | - Sherri L Surman
- Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
| | - Rhiannon R Penkert
- Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
| | - Stephane Pelletier
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
| | - Geoff Neale
- The Hartwell Center for Bioinformatics & Biotechnology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
| | - Julia L Hurwitz
- Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
- Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, TN 38163, USA.
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18
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Shi J, Chen Y, Chen W, Tang C, Zhang H, Chen Y, Yang X, Xu Z, Wei J, Chen J. Isobavachalcone sensitizes cells to E2-induced paclitaxel resistance by down-regulating CD44 expression in ER+ breast cancer cells. J Cell Mol Med 2018; 22:5220-5230. [PMID: 30179299 PMCID: PMC6201375 DOI: 10.1111/jcmm.13719] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 05/13/2018] [Indexed: 12/16/2022] Open
Abstract
Oestrogen receptor (ER) is expressed in approximately 60%‐70% of human breast cancer. Clinical trials and retrospective analyses have shown that ER‐positive (ER+) tumours are more tolerant to chemotherapeutic drug resistance than ER‐negative (ER−) tumours. In addition, isobavachalcone (IBC) is known as a kind of phytoestrogen with antitumour effect. However, the underlying mechanism of IBC in ER+ breast cancer needs to be elucidated further. Our in vitro experiments showed that IBC could attenuate 17β‐estradiol (E2)‐induced paclitaxel resistance and that E2 could stimulate CD44 expression in ER+ breast cancer cells but not in ER− cells. Meanwhile, E2 could promote ERα expression to render ER+ breast cancer cells resistant to paclitaxel. Furthermore, we established paclitaxel‐resistant breast cancer cell lines and determined the function of ERα in the enhancement of paclitaxel resistance via the regulation of CD44 transcription. IBC down‐regulated ERα and CD44 expression and thus inhibited tumour growth in paclitaxel‐resistant xenograft models. Overall, our data demonstrated for the first time that IBC could decrease CD44 expression level via the ERα pathway and make ER+ breast cancer cells sensitive to paclitaxel treatment.
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Affiliation(s)
- Junfeng Shi
- Department of Oncology, Nanjing First Hospital, NanJing Medical University, Nanjing, China.,Clinical Research Center, Xuyi People's Hospital, Xuyi, China
| | - Yi Chen
- Department of Oncology, Nanjing Pukou Central Hospital, Nanjing, China
| | - Wenxing Chen
- School of pharmacy, Nanjing University of Chinese Medicine, Nanjing, China
| | - Cuiju Tang
- Department of Oncology, Nanjing First Hospital, NanJing Medical University, Nanjing, China
| | - Honghong Zhang
- Department of Oncology, Nanjing First Hospital, NanJing Medical University, Nanjing, China
| | - Yuetong Chen
- Department of Oncology, Nanjing First Hospital, NanJing Medical University, Nanjing, China
| | - Xiuwei Yang
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, KY, USA
| | - Zhi Xu
- Department of Oncology, Nanjing First Hospital, NanJing Medical University, Nanjing, China
| | - Jingsun Wei
- Department of Oncology, Nanjing First Hospital, NanJing Medical University, Nanjing, China
| | - Jinfei Chen
- Department of Oncology, Nanjing First Hospital, NanJing Medical University, Nanjing, China.,Clinical Research Center, Xuyi People's Hospital, Xuyi, China.,Jiangsu Key Lab of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Cancer Personalized Medicine, Nanjing Medical University, Nanjing, China
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19
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Mustafin RN, Khusnutdinova EK. The Role of Transposons in Epigenetic Regulation of Ontogenesis. Russ J Dev Biol 2018. [DOI: 10.1134/s1062360418020066] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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20
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Vrljicak P, Lucas ES, Lansdowne L, Lucciola R, Muter J, Dyer NP, Brosens JJ, Ott S. Analysis of chromatin accessibility in decidualizing human endometrial stromal cells. FASEB J 2018; 32:2467-2477. [PMID: 29259032 PMCID: PMC6040682 DOI: 10.1096/fj.201701098r] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Spontaneous decidualization of the endometrium in response to progesterone signaling is confined to menstruating species, including humans and other higher primates. During this process, endometrial stromal cells (EnSCs) differentiate into specialized decidual cells that control embryo implantation. We subjected undifferentiated and decidualizing human EnSCs to an assay for transposase accessible chromatin with sequencing (ATAC-seq) to map the underlying chromatin changes. A total of 185,084 open DNA loci were mapped accurately in EnSCs. Altered chromatin accessibility upon decidualization was strongly associated with differential gene expression. Analysis of 1533 opening and closing chromatin regions revealed over-representation of DNA binding motifs for known decidual transcription factors (TFs) and identified putative new regulators. ATAC-seq footprint analysis provided evidence of TF binding at specific motifs. One of the largest footprints involved the most enriched motif-basic leucine zipper-as part of a triple motif that also comprised the estrogen receptor and Pax domain binding sites. Without exception, triple motifs were located within Alu elements, which suggests a role for this primate-specific transposable element (TE) in the evolution of decidual genes. Although other TEs were generally under-represented in open chromatin of undifferentiated EnSCs, several classes contributed to the regulatory DNA landscape that underpins decidual gene expression.-Vrljicak, P., Lucas, E. S., Lansdowne, L., Lucciola, R., Muter, J., Dyer, N. P., Brosens, J. J., Ott, S. Analysis of chromatin accessibility in decidualizing human endometrial stromal cells.
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Affiliation(s)
- Pavle Vrljicak
- Tommy's National Centre for Miscarriage Research, Warwick Medical School, University Hospitals Coventry and Warwickshire National Health Service (NHS) Trust, United Kingdom.,Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, United Kingdom
| | - Emma S Lucas
- Tommy's National Centre for Miscarriage Research, Warwick Medical School, University Hospitals Coventry and Warwickshire National Health Service (NHS) Trust, United Kingdom.,Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, United Kingdom
| | - Lauren Lansdowne
- Department of Computer Science, University of Warwick, Coventry, United Kingdom
| | - Raffaella Lucciola
- Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, United Kingdom
| | - Joanne Muter
- Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, United Kingdom
| | - Nigel P Dyer
- Department of Computer Science, University of Warwick, Coventry, United Kingdom
| | - Jan J Brosens
- Tommy's National Centre for Miscarriage Research, Warwick Medical School, University Hospitals Coventry and Warwickshire National Health Service (NHS) Trust, United Kingdom.,Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, United Kingdom
| | - Sascha Ott
- Tommy's National Centre for Miscarriage Research, Warwick Medical School, University Hospitals Coventry and Warwickshire National Health Service (NHS) Trust, United Kingdom.,Department of Computer Science, University of Warwick, Coventry, United Kingdom
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21
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Adurthi S, Kumar MM, Vinodkumar HS, Mukherjee G, Krishnamurthy H, Acharya KK, Bafna UD, Uma DK, Abhishekh B, Krishna S, Parchure A, Alka M, Jayshree RS. Oestrogen Receptor-α binds the FOXP3 promoter and modulates regulatory T-cell function in human cervical cancer. Sci Rep 2017; 7:17289. [PMID: 29229929 PMCID: PMC5725534 DOI: 10.1038/s41598-017-17102-w] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 11/14/2017] [Indexed: 01/07/2023] Open
Abstract
Oestrogen controls Foxp3 expression in regulatory T cells (Treg cells) via a mechanism thought to involve oestrogen receptor alpha (ERα), but the molecular basis and functional impact of ERα signalling in Treg cells remain unclear. We report that ERα ligand oestradiol (E2) is significantly increased in human cervical cancer (CxCa) tissues and tumour-infiltrating Treg cells (CD4+CD25hiCD127low), whereas blocking ERα with the antagonist ICI 182,780 abolishes FOXP3 expression and impairs the function of CxCa infiltrating Treg cells. Using a novel approach of co-immunoprecipitation with antibodies to E2 for capture, we identified binding of E2:ERα complexes to FOXP3 protein in CxCa-derived Treg cells. Chromatin immunoprecipitation analyses of male blood Treg cells revealed ERα occupancy at the FOXP3 promoter and conserved non-coding DNA elements 2 and 3. Accordingly, computational analyses of the enriched regions uncovered eight putative oestrogen response elements predicted to form a loop that can activate the FOXP3 promoter. Together, these data suggest that E2-mediated ERα signalling is critical for the sustenance of FOXP3 expression and Treg cell function in human CxCa via direct interaction of ERα with FOXP3 promoter. Overall, our work gives a molecular insight into ERα signalling and highlights a fundamental role of E2 in controlling human Treg cell physiology.
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Affiliation(s)
- Sreenivas Adurthi
- Department of Microbiology, Kidwai Memorial Institute of Oncology, Bangalore, India
| | - Mahesh M Kumar
- Department of Microbiology, Kidwai Memorial Institute of Oncology, Bangalore, India
| | - H S Vinodkumar
- Shodhaka Life Sciences Private Limited, Bangalore, India
- Structural Biology Lab, School of Bio Sciences and Technology, Vellore Institute of Technology, Vellore, India
| | - Geetashree Mukherjee
- Department of Pathology, Kidwai Memorial Institute of Oncology, Bangalore, India
- Department of Histopathology, Tata Medical Center, Kolkata, India
| | - H Krishnamurthy
- National Center for Biological Sciences, TIFR, Bangalore, India
| | - K Kshitish Acharya
- Shodhaka Life Sciences Private Limited, Bangalore, India
- Institute of Bioinformatics And Applied Biotechnology, Bangalore, India
| | - U D Bafna
- Department of Gynecology, Kidwai Memorial Institute of Oncology, Bangalore, India
| | - Devi K Uma
- Department of Gynecology, Kidwai Memorial Institute of Oncology, Bangalore, India
| | - B Abhishekh
- Department of Immunohematology, Kidwai Memorial Institute of Oncology, Bangalore, India
- Department of Transfusion Medicine, JIPMER, Puducherry, India
| | - Sudhir Krishna
- National Center for Biological Sciences, TIFR, Bangalore, India
| | - A Parchure
- Department of Microbiology, Kidwai Memorial Institute of Oncology, Bangalore, India
| | - Murali Alka
- Department of Microbiology, Kidwai Memorial Institute of Oncology, Bangalore, India
| | - R S Jayshree
- Department of Microbiology, Kidwai Memorial Institute of Oncology, Bangalore, India.
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22
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Yao G, Hu S, Yu L, Ru Y, Chen CD, Liu Q, Zhang Y. Genome-Wide Mapping of In Vivo ERα-Binding Sites in Male Mouse Efferent Ductules. Endocrinology 2017. [PMID: 28645209 DOI: 10.1210/en.2017-00483] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
As an important nuclear hormone receptor, estrogen receptor α (ERα), which is encoded by the Esr1 gene, regulates the expression of hundreds of genes in a stimulus-specific, temporal, and tissue-specific fashion, mainly by binding to specific DNA sequences called estrogen response elements (EREs). As an important estrogen target tissue in males, the function of the efferent ductules relies on the presence of the ERα protein, but the underlying regulatory mechanisms are poorly illustrated. In this study, genome-wide ERα-binding sites in mouse efferent ductules were mapped by chromatin immunoprecipitation sequencing. In total, 12,105 peaks were identified, and a majority of them were located far from the annotated gene transcription start site. Motif analysis revealed that ∼80% of the ERα-binding peaks harbored at least one ERE, whereas androgen response element-like sequences were the most overrepresented motif in the peaks without any EREs. A number of candidate transcription factor motifs adjacent to the EREs were significantly enriched, including AP2 and GRE, implying the involvement of these putative adjacent factors in the global regulation of ERα target genes. Unexpectedly, more than 50% of the ERα-binding peaks in mouse efferent ductules overlapped with those binding peaks previously identified in mouse uterus, suggesting the conserved mechanism of ERα action in these two tissues. Cobinding of ERα target genes by androgen receptor was further confirmed for Slc9a3 gene, which was responsible for fluid resorption in the efferent ductules. Taken together, our study provides a useful reference set for future work aimed at exploring the mechanism of ERα action in physiological conditions.
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Affiliation(s)
- Guangxin Yao
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai 200031, People's Republic of China
- Shanghai Key Laboratory for Assisted Reproduction and Reproductive Genetics, Center for Reproductive Medicine, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200135, People's Republic of China
| | - Shuanggang Hu
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai 200031, People's Republic of China
- Shanghai Key Laboratory for Assisted Reproduction and Reproductive Genetics, Center for Reproductive Medicine, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200135, People's Republic of China
| | - Lu Yu
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai 200031, People's Republic of China
| | - Yanfei Ru
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai 200031, People's Republic of China
| | - Charlie Degui Chen
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai 200031, People's Republic of China
| | - Qiang Liu
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai 200031, People's Republic of China
- Shanghai Key Laboratory of Reproductive Medicine, Department of Histoembryology, Genetics and Developmental Biology, School of Medicine, Shanghai Jiao Tong University, Shanghai 200025, People's Republic of China
| | - Yonglian Zhang
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai 200031, People's Republic of China
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BRCA1-mimetic compound NSC35446.HCl inhibits IKKB expression by reducing estrogen receptor-α occupancy in the IKKB promoter and inhibits NF-κB activity in antiestrogen-resistant human breast cancer cells. Breast Cancer Res Treat 2017; 166:681-693. [PMID: 28808806 DOI: 10.1007/s10549-017-4442-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Accepted: 08/04/2017] [Indexed: 10/19/2022]
Abstract
PURPOSE We previously identified small molecules that fit into a BRCA1-binding pocket within estrogen receptor-alpha (ERα), mimic the ability of BRCA1 to inhibit ERα activity ("BRCA1-mimetics"), and overcome antiestrogen resistance. One such compound, the hydrochloride salt of NSC35446 ("NSC35446.HCl"), also inhibited the growth of antiestrogen-resistant LCC9 tumor xenografts. The purpose of this study was to investigate the down-stream effects of NSC35446.HCl and its mechanism of action. METHODS Here, we studied antiestrogen-resistant (LCC9, T47DCO, MCF-7/RR, LY2), ERα-negative (MDA-MB-231, HCC1806, MDA-MB-468), and antiestrogen-sensitive (MCF-7) cell lines. Techniques utilized include RNA-seq, qRT-PCR, cell growth analysis, cell-cycle analysis, Western blotting, luciferase reporter assays, TUNEL assays, in silico analysis of the IKKB gene, and ChIP assays. RESULTS SC35446.HCl inhibited proliferation and induced apoptosis in antiestrogen-resistant LCC9, T47DCO, MCF-7/RR, and LY2 cells but not in ERα-negative breast cancer cell lines. IKKB (IKKβ, IKBKB), an upstream activator of NF-κB, was identified as a BRCA1-mimetic-regulated gene based on an RNA-seq analysis. NSC35446.HCl inhibited IKKB, IKKA, and IKKG/NEMO mRNA and protein expression in LCC9 cells. NSC35446.HCl also inhibited NF-κB activity and expression of NF-κB target genes. In silico analysis of the IKKB promoter identified nine estrogen response element (ERE) half-sites and one ERE-like full-site. ChIP assays revealed that ERα was recruited to the ERE-like full-site and five of the nine half-sites and that ERα recruitment was inhibited by NSC35446.HCl in LCC9 and T47DCO cells. CONCLUSIONS These studies identify functional EREs in the IKKB promoter and identify IKKB as an ERα and NSC35446.HCl-regulated gene, and they suggest that NF-κB and IKKB, which were previously linked to antiestrogen resistance, are targets for NSC35446.HCl in reversing antiestrogen resistance.
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Linker SB, Marchetto MC, Narvaiza I, Denli AM, Gage FH. Examining non-LTR retrotransposons in the context of the evolving primate brain. BMC Biol 2017; 15:68. [PMID: 28800766 PMCID: PMC5554003 DOI: 10.1186/s12915-017-0409-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Researchers have long sought to understand the genetic basis of the cognitive differences between primates, with particular focus on the human brain. Although all mutational types have worked in concert with evolutionary forces to generate the current human brain, in this review we will explore the impact of mobile elements, specifically non-LTR retrotransposons. Non-LTR retrotransposons have contributed coding and regulatory sequences to the genome throughout evolution. During primate evolution there have been multiple waves of LINE retrotransposition as well as the birth of new mobile elements such as the SINEs Alu and SVA and we will explore what kinds of impacts these may have had on the evolving human brain.
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Affiliation(s)
- Sara B Linker
- Salk Institute for Biological Studies, La Jolla, CA, 92037-1002, USA
| | - Maria C Marchetto
- Salk Institute for Biological Studies, La Jolla, CA, 92037-1002, USA
| | - Iñigo Narvaiza
- Salk Institute for Biological Studies, La Jolla, CA, 92037-1002, USA
| | - Ahmet M Denli
- Salk Institute for Biological Studies, La Jolla, CA, 92037-1002, USA
| | - Fred H Gage
- Salk Institute for Biological Studies, La Jolla, CA, 92037-1002, USA.
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25
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Tran TKA, MacFarlane GR, Kong RYC, O'Connor WA, Yu RMK. The constitutively active estrogen receptor (ER) binds and activates the promoter of the vitellogenin (Vtg) gene in the Sydney rock oyster, Saccostrea glomerata. MARINE POLLUTION BULLETIN 2017; 118:397-402. [PMID: 28259423 DOI: 10.1016/j.marpolbul.2017.02.060] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 02/17/2017] [Accepted: 02/22/2017] [Indexed: 06/06/2023]
Abstract
Vitellogenin (Vtg) is a well-established biomarker of estrogenic exposure in aquatic animals. In vertebrates, Vtg gene transcription is controlled by the estrogen receptors (ERs). Although an ER ortholog is present in molluscs, its role as a transcriptional regulator remains elusive. Here, we tested the hypothesis that in the Sydney rock oyster, Saccostrea glomerata, the ER ortholog activates Vtg gene transcription through specific interaction with its promoter. Luciferase reporter assays indicated that sgER activated both a minimal promoter containing the consensus estrogen-responsive elements (EREs) and the sgVtg promoter in an estrogen-independent manner. The sgVtg promoter-luciferase activation was significantly reduced when any of three putative ERE half sites (½EREs) in the promoter were mutated. Electrophoretic mobility shift assay (EMSA) confirmed that sgER binds specifically to a 68-bp promoter sequence where these ½EREs reside. Overall, the results suggest that sgER is a constitutively active transcription factor that binds and activates the sgVtg promoter.
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Affiliation(s)
- Thi Kim Anh Tran
- School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW 2308, Australia; Department of Agriculture, Forestry and Fisheries, Vinh University, 182 Le Duan St., Vinh City, Nghe An, Vietnam
| | - Geoff R MacFarlane
- School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW 2308, Australia
| | - Richard Yuen Chong Kong
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
| | - Wayne A O'Connor
- New South Wales Department of Primary Industries, Port Stephens Fisheries Institute, Taylors Beach, NSW 2316, Australia
| | - Richard Man Kit Yu
- School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW 2308, Australia.
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Warren IA, Naville M, Chalopin D, Levin P, Berger CS, Galiana D, Volff JN. Evolutionary impact of transposable elements on genomic diversity and lineage-specific innovation in vertebrates. Chromosome Res 2016; 23:505-31. [PMID: 26395902 DOI: 10.1007/s10577-015-9493-5] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Since their discovery, a growing body of evidence has emerged demonstrating that transposable elements are important drivers of species diversity. These mobile elements exhibit a great variety in structure, size and mechanisms of transposition, making them important putative actors in organism evolution. The vertebrates represent a highly diverse and successful lineage that has adapted to a wide range of different environments. These animals also possess a rich repertoire of transposable elements, with highly diverse content between lineages and even between species. Here, we review how transposable elements are driving genomic diversity and lineage-specific innovation within vertebrates. We discuss the large differences in TE content between different vertebrate groups and then go on to look at how they affect organisms at a variety of levels: from the structure of chromosomes to their involvement in the regulation of gene expression, as well as in the formation and evolution of non-coding RNAs and protein-coding genes. In the process of doing this, we highlight how transposable elements have been involved in the evolution of some of the key innovations observed within the vertebrate lineage, driving the group's diversity and success.
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Affiliation(s)
- Ian A Warren
- Institut de Génomique Fonctionnelle de Lyon, CNRS UMR5242, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Magali Naville
- Institut de Génomique Fonctionnelle de Lyon, CNRS UMR5242, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Domitille Chalopin
- Institut de Génomique Fonctionnelle de Lyon, CNRS UMR5242, Ecole Normale Supérieure de Lyon, Lyon, France.,Department of Genetics, University of Georgia, Athens, Georgia, 30602, USA
| | - Perrine Levin
- Institut de Génomique Fonctionnelle de Lyon, CNRS UMR5242, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Chloé Suzanne Berger
- Institut de Génomique Fonctionnelle de Lyon, CNRS UMR5242, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Delphine Galiana
- Institut de Génomique Fonctionnelle de Lyon, CNRS UMR5242, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Jean-Nicolas Volff
- Institut de Génomique Fonctionnelle de Lyon, CNRS UMR5242, Ecole Normale Supérieure de Lyon, Lyon, France.
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Lin C, Yang D. DNA Recognition by a Novel Bis-Intercalator, Potent Anticancer Drug XR5944. Curr Top Med Chem 2016; 15:1385-97. [PMID: 25866279 DOI: 10.2174/1568026615666150413155608] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Revised: 12/19/2014] [Accepted: 12/19/2014] [Indexed: 12/21/2022]
Abstract
XR5944 is a potent anticancer drug with a novel DNA binding mode: DNA bisintercalationg with major groove binding. XR5944 can bind the estrogen response element (ERE) sequence to block ER-ERE binding and inhibit ERα activities, which may be useful for overcoming drug resistance to currently available antiestrogen treatments. This review discusses the progress relating to the structure and function studies of specific DNA recognition of XR5944. The sites of intercalation within a native promoter sequence appear to be different from the ideal binding site and are context- and sequence- dependent. The structural information may provide insights for rational design of improved EREspecific XR5944 derivatives, as well as of DNA bis-intercalators in general.
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Affiliation(s)
| | - Danzhou Yang
- College of Pharmacy, University of Arizona, 1703 E. Mabel St, Tucson, AZ 85721, USA.
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Tran TKA, MacFarlane GR, Kong RYC, O'Connor WA, Yu RMK. Mechanistic insights into induction of vitellogenin gene expression by estrogens in Sydney rock oysters, Saccostrea glomerata. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2016; 174:146-158. [PMID: 26963518 DOI: 10.1016/j.aquatox.2016.02.023] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Revised: 02/25/2016] [Accepted: 02/27/2016] [Indexed: 06/05/2023]
Abstract
Marine molluscs, such as oysters, respond to estrogenic compounds with the induction of the egg yolk protein precursor, vitellogenin (Vtg), availing a biomarker for estrogenic pollution. Despite this application, the precise molecular mechanism through which estrogens exert their action to induce molluscan vitellogenesis is unknown. As a first step to address this question, we cloned a gene encoding Vtg from the Sydney rock oyster Saccostrea glomerata (sgVtg). Using primers designed from a partial sgVtg cDNA sequence available in Genbank, a full-length sgVtg cDNA of 8498bp was obtained by 5'- and 3'-RACE. The open reading frame (ORF) of sgVtg was determined to be 7980bp, which is substantially longer than the orthologs of other oyster species. Its deduced protein sequence shares the highest homology at the N- and C-terminal regions with other molluscan Vtgs. The full-length genomic DNA sequence of sgVtg was obtained by genomic PCR and genome walking targeting the gene body and flanking regions, respectively. The genomic sequence spans 20kb and consists of 30 exons and 29 introns. Computer analysis identified three closely spaced half-estrogen responsive elements (EREs) in the promoter region and a 210-bp CpG island 62bp downstream of the transcription start site. Upregulation of sgVtg mRNA expression was observed in the ovaries following in vitro (explants) and in vivo (tank) exposure to 17β-estradiol (E2). Notably, treatment with an estrogen receptor (ER) antagonist in vitro abolished the upregulation, suggesting a requirement for an estrogen-dependent receptor for transcriptional activation. DNA methylation of the 5' CpG island was analysed using bisulfite genomic sequencing of the in vivo exposed ovaries. The CpG island was found to be hypomethylated (with 0-3% methylcytosines) in both control and E2-exposed oysters. However, no significant differential methylation or any correlation between methylation and sgVtg expression levels was observed. Overall, the results support the possible involvement of an ERE-containing promoter and an estrogen-activated receptor in estrogen signalling in marine molluscs.
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Affiliation(s)
- Thi Kim Anh Tran
- School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW 2308, Australia
| | - Geoff R MacFarlane
- School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW 2308, Australia
| | - Richard Yuen Chong Kong
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region, China
| | - Wayne A O'Connor
- New South Wales Department of Primary Industries, Port Stephens Fisheries Institute, Taylors Beach, NSW 2316, Australia
| | - Richard Man Kit Yu
- School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW 2308, Australia.
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Ali HO, Stavik B, Myklebust CF, Andersen E, Dahm AEA, Iversen N, Sandset PM, Skretting G. Oestrogens Downregulate Tissue Factor Pathway Inhibitor through Oestrogen Response Elements in the 5'-Flanking Region. PLoS One 2016; 11:e0152114. [PMID: 26999742 PMCID: PMC4801176 DOI: 10.1371/journal.pone.0152114] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Accepted: 03/09/2016] [Indexed: 11/21/2022] Open
Abstract
Oestrogens influence the pathology and development of hormone-sensitive breast cancers. Tissue factor pathway inhibitor (TFPI) has been shown to be associated with breast cancer pathogenesis. Recently, we found TFPI mRNA levels to be significantly reduced by oestrogens in a breast cancer cell line (MCF7), a process mediated through the oestrogen receptor alpha (ERα). The aim of the present study was to investigate the mechanism(s) by which oestrogens may regulate TFPI at the transcriptional level. The TFPI 5’-flanking region contains three oestrogen response element (ERE) half-sites at positions -845, -769 and -50. Constructs containing the wild type or mutated ERE half-sites of the TFPI 5’-flanking region were generated in a luciferase reporter gene vector and transiently co-transfected with an ERα expression vector into HEK293 cells and subsequently treated with oestrogens. We found that luciferase activity was significantly downregulated after oestrogen stimulation in cells transfected with the wild type construct, an effect that was abolished by mutating either ERE half-sites. Electrophoretic mobility shift assay suggested direct and specific interaction of ERα with the ERE half-sites in the TFPI 5’-flanking region. Chromatin immunoprecipitation showed that ERα was recruited to the region -899 to -578 of the TFPI 5’-flanking region in vivo, where the ERE half-sites -845 and -769 are located. Our results indicate that ERα can interact with all three ERE half-sites in the TFPI 5’-flanking region and thus participate in the repression of oestrogen mediated TFPI transcription in breast cancer cells.
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Affiliation(s)
- Huda Omar Ali
- Department of Haematology, Oslo University Hospital, Oslo, Norway
- Research Institute of Internal Medicine, Oslo University Hospital, Oslo, Norway
- Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Benedicte Stavik
- Department of Haematology, Oslo University Hospital, Oslo, Norway
- Research Institute of Internal Medicine, Oslo University Hospital, Oslo, Norway
| | - Christiane Filion Myklebust
- Department of Haematology, Oslo University Hospital, Oslo, Norway
- Research Institute of Internal Medicine, Oslo University Hospital, Oslo, Norway
| | - Elisabeth Andersen
- Department of Haematology, Oslo University Hospital, Oslo, Norway
- Research Institute of Internal Medicine, Oslo University Hospital, Oslo, Norway
- Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Anders E. A. Dahm
- Research Institute of Internal Medicine, Oslo University Hospital, Oslo, Norway
- Institute of Clinical Medicine, University of Oslo, Oslo, Norway
- Department of Haematology, Akershus University Hospital, Nordbyhagen, Norway
| | - Nina Iversen
- Department of Medical Genetics, Oslo University Hospital, Oslo, Norway
| | - Per Morten Sandset
- Department of Haematology, Oslo University Hospital, Oslo, Norway
- Research Institute of Internal Medicine, Oslo University Hospital, Oslo, Norway
- Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Grethe Skretting
- Department of Haematology, Oslo University Hospital, Oslo, Norway
- Research Institute of Internal Medicine, Oslo University Hospital, Oslo, Norway
- * E-mail:
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Cao DY, Bai G, Ji Y, Traub RJ. Epigenetic upregulation of metabotropic glutamate receptor 2 in the spinal cord attenuates oestrogen-induced visceral hypersensitivity. Gut 2015; 64:1913-20. [PMID: 25378524 PMCID: PMC4562903 DOI: 10.1136/gutjnl-2014-307748] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Accepted: 10/16/2014] [Indexed: 12/08/2022]
Abstract
OBJECTIVE Epigenetic mechanisms are potential targets to relieve somatic pain. However, little is known whether epigenetic regulation interferes with visceral pain. Previous studies show that oestrogen facilitates visceral pain. This study aimed to determine whether histone hyperacetylation in the spinal cord could attenuate oestrogen-facilitated visceral pain. DESIGN The effect of the histone deacetylase inhibitor suberoylanilide hydroxamic acid (SAHA) on the magnitude of the visceromotor response (VMR) to colorectal distention was examined in ovariectomised rats with/without oestrogen replacement. An additional interaction with the metabotropic glutamate receptor 2/3 (mGluR2/3) antagonist LY341495 was tested. The levels of acetylated histone and mGluR2 mRNA and protein were analysed. The binding of acetylated H3 and oestrogen receptor α (ERα) to the GRM2 promoter was measured by chromatin immunoprecipitation coupled with qPCR. RESULTS In ovariectomised rats, 17β-estradiol (E2), but not safflower oil, increased the magnitude of the VMR to colorectal distention. SAHA attenuated the E2-facilitated VMR, but had no effect in safflower oil-treated rats. Subsequent spinal administration of LY341495 reversed the antinociceptive effect of SAHA in E2 rats. In addition, SAHA increased mGluR2 mRNA and protein in the spinal dorsal horn following E2, but not vehicle, treatment. In contrast, neither E2 nor SAHA alone altered mGluR2 mRNA. SAHA increased binding of H3K9ac and ERα to the same regions of the GRM2 promoter in E2-SAHA-treated animals. CONCLUSIONS Histone hyperacetylation in the spinal cord attenuates the pronociceptive effects of oestrogen on visceral sensitivity, suggesting that epigenetic regulation may be a potential approach to relieve visceral pain.
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Affiliation(s)
- Dong-Yuan Cao
- Department of Neural and Pain Sciences, University of Maryland School of Dentistry, UM Center to Advance Chronic Pain Research, Baltimore, Maryland, USA
| | - Guang Bai
- Department of Neural and Pain Sciences, University of Maryland School of Dentistry, UM Center to Advance Chronic Pain Research, Baltimore, Maryland, USA
| | - Yaping Ji
- Department of Neural and Pain Sciences, University of Maryland School of Dentistry, UM Center to Advance Chronic Pain Research, Baltimore, Maryland, USA
| | - Richard J Traub
- Department of Neural and Pain Sciences, University of Maryland School of Dentistry, UM Center to Advance Chronic Pain Research, Baltimore, Maryland, USA
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Spanier JA, Nashold FE, Mayne CG, Nelson CD, Hayes CE. Vitamin D and estrogen synergy in Vdr-expressing CD4+ T cells is essential to induce Helios+FoxP3+ T cells and prevent autoimmune demyelinating disease. J Neuroimmunol 2015; 286:48-58. [DOI: 10.1016/j.jneuroim.2015.06.015] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Revised: 06/16/2015] [Accepted: 06/19/2015] [Indexed: 01/08/2023]
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Pendleton M, Sebra R, Pang AWC, Ummat A, Franzen O, Rausch T, Stütz AM, Stedman W, Anantharaman T, Hastie A, Dai H, Fritz MHY, Cao H, Cohain A, Deikus G, Durrett RE, Blanchard SC, Altman R, Chin CS, Guo Y, Paxinos EE, Korbel JO, Darnell RB, McCombie WR, Kwok PY, Mason CE, Schadt EE, Bashir A. Assembly and diploid architecture of an individual human genome via single-molecule technologies. Nat Methods 2015; 12:780-6. [PMID: 26121404 PMCID: PMC4646949 DOI: 10.1038/nmeth.3454] [Citation(s) in RCA: 330] [Impact Index Per Article: 36.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Accepted: 05/28/2015] [Indexed: 12/30/2022]
Abstract
We present the first comprehensive analysis of a diploid human genome that combines single-molecule sequencing with single-molecule genome maps. Our hybrid assembly markedly improves upon the contiguity observed from traditional shotgun sequencing approaches, with scaffold N50 values approaching 30 Mb, and we identified complex structural variants (SVs) missed by other high-throughput approaches. Furthermore, by combining Illumina short-read data with long reads, we phased both single-nucleotide variants and SVs, generating haplotypes with over 99% consistency with previous trio-based studies. Our work shows that it is now possible to integrate single-molecule and high-throughput sequence data to generate de novo assembled genomes that approach reference quality.
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Affiliation(s)
- Matthew Pendleton
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Robert Sebra
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | | | - Ajay Ummat
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Oscar Franzen
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Tobias Rausch
- Genome Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Adrian M Stütz
- Genome Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | | | | | - Alex Hastie
- BioNano Genomics, San Diego, California, USA
| | - Heng Dai
- BioNano Genomics, San Diego, California, USA
| | | | - Han Cao
- BioNano Genomics, San Diego, California, USA
| | - Ariella Cohain
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Gintaras Deikus
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Russell E Durrett
- The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medical College, New York, New York, USA
| | - Scott C Blanchard
- Department of Physiology and Biophysics, Weill Cornell Medical College, New York, New York, USA
| | - Roger Altman
- The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medical College, New York, New York, USA
| | | | - Yan Guo
- Pacific Biosciences, Menlo Park, California, USA
| | | | - Jan O Korbel
- 1] Genome Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany. [2] European Bioinformatics Institute, European Molecular Biology Laboratory, Hinxton, UK
| | - Robert B Darnell
- 1] Laboratory of Neuro-Oncology, The Rockefeller University, New York, New York, USA. [2] Howard Hughes Medical Institute, New York, New York, USA
| | - W Richard McCombie
- 1] The Stanley Institute for Cognitive Genomics, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, USA. [2] The Watson School of Biological Sciences, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, USA
| | - Pui-Yan Kwok
- Institute for Human Genetics, University of California-San Francisco, San Francisco, California, USA
| | - Christopher E Mason
- 1] The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medical College, New York, New York, USA. [2] Department of Medicine, Division of Hematology/Oncology, Weill Cornell Medical College, New York, New York, USA. [3] The Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, New York, USA
| | - Eric E Schadt
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Ali Bashir
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
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Dynamic Alu methylation during normal development, aging, and tumorigenesis. BIOMED RESEARCH INTERNATIONAL 2014; 2014:784706. [PMID: 25243180 PMCID: PMC4163490 DOI: 10.1155/2014/784706] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Accepted: 08/16/2014] [Indexed: 12/15/2022]
Abstract
DNA methylation primarily occurs on CpG dinucleotides and plays an important role in transcriptional regulations during tissue development and cell differentiation. Over 25% of CpG dinucleotides in the human genome reside within Alu elements, the most abundant human repeats. The methylation of Alu elements is an important mechanism to suppress Alu transcription and subsequent retrotransposition. Decades of studies revealed that Alu methylation is highly dynamic during early development and aging. Recently, many environmental factors were shown to have a great impact on Alu methylation. In addition, aberrant Alu methylation has been documented to be an early event in many tumors and Alu methylation levels have been associated with tumor aggressiveness. The assessment of the Alu methylation has become an important approach for early diagnosis and/or prognosis of cancer. This review focuses on the dynamic Alu methylation during development, aging, and tumor genesis. The cause and consequence of Alu methylation changes will be discussed.
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Shi JF, Yang N, Ding HJ, Zhang JX, Hu ML, Leng Y, Han X, Sun YJ. ERα directly activated the MDR1 transcription to increase paclitaxel-resistance of ERα-positive breast cancer cells in vitro and in vivo. Int J Biochem Cell Biol 2014; 53:35-45. [PMID: 24786296 DOI: 10.1016/j.biocel.2014.04.016] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Revised: 04/10/2014] [Accepted: 04/17/2014] [Indexed: 01/14/2023]
Abstract
Chemotherapy is commonly used to treat early-stage invasive and advanced-stage breast cancer either before or after surgery. Increasing evidence from clinical analysis and in vitro studies has shown that ER-positive breast cancer cells are insensitive to chemotherapy. Complete understanding of how ERα mediates drug resistance is prerequisite to improvement of the chemotherapeutic efficacy. Over-expression of P-glycoprotein (P-gp) encoded by MDR1 gene is one of the major causes of drug resistance. The association between ERα and MDR1 in breast cancer is still unclear and the limited reports are conflict. This study systematically explored intrinsic link between ERα and the P-gp over-expression in paclitaxel-resistant ERα(+) breast cancer cell lines and mouse model in molecular details. Our data showed that ERα activated the MDR1 transcription in MCF-7/PTX breast cancer cells by binding to ERE1/2 and interacting with Sp1 that bridged to the downstream CG-rich element within the MDR1 promoter. Knockdown of MDR1 restrained the effect of ERα in MCF-7 cells and sensitized the cells to paclitaxel. Treatment of ICI 182,780 that selectively suppressed ERα significantly decreased the MDR1 expression and increased the sensitivity of drug resistant breast cancer cells and xenograft tumors to paclitaxel. Our data strongly demonstrated that ERα was able to increase drug resistance of breast cancer cells through activating MDR1 transcription. This novel mechanism provides new insight to how the ERα signaling regulates response of ERα(+) breast tumors to chemotherapy, which may be exploited for developing novel therapeutic strategies for breast cancer in the future.
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Affiliation(s)
- Jun-Feng Shi
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, China; Key Laboratory of Human Functional Genomics of Jiangsu Province, Nanjing Medical University, Nanjing, China; Department of Cell Biology, Nanjing Medical University, Nanjing, China
| | - Nan Yang
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Nanjing Medical University, Nanjing, China
| | - Hai-Jian Ding
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Nanjing Medical University, Nanjing, China; Department of Cell Biology, Nanjing Medical University, Nanjing, China
| | - Jie-Xin Zhang
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Nanjing Medical University, Nanjing, China
| | - Mei-Ling Hu
- Department of Cell Biology, Nanjing Medical University, Nanjing, China
| | - Yan Leng
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Nanjing Medical University, Nanjing, China; Department of Cell Biology, Nanjing Medical University, Nanjing, China
| | - Xiao Han
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, China; Key Laboratory of Human Functional Genomics of Jiangsu Province, Nanjing Medical University, Nanjing, China
| | - Yu-Jie Sun
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, China; Key Laboratory of Human Functional Genomics of Jiangsu Province, Nanjing Medical University, Nanjing, China; Department of Cell Biology, Nanjing Medical University, Nanjing, China; Jiangsu Key Lab of Cancer Biomarkers, Prevention & Treatment, Cancer Center, Nanjing Medical University, Nanjing, China.
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Lin C, Mathad RI, Zhang Z, Sidell N, Yang D. Solution structure of a 2:1 complex of anticancer drug XR5944 with TFF1 estrogen response element: insights into DNA recognition by a bis-intercalator. Nucleic Acids Res 2014; 42:6012-24. [PMID: 24711371 PMCID: PMC4027214 DOI: 10.1093/nar/gku219] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
XR5944, a deoxyribonucleic acid (DNA) bis-intercalator with potent anticancer activity, can bind the estrogen response element (ERE) sequence to inhibit estrogen receptor-α activities. This novel mechanism of action may be useful for overcoming drug resistance to currently available antiestrogen treatments, all of which target the hormone-receptor complex. Here we report the nuclear magnetic resonance solution structure of the 2:1 complex of XR5944 with the naturally occurring TFF1-ERE, which exhibits important and unexpected features. In both drug–DNA complexes, XR5944 binds strongly at one intercalation site but weakly at the second site. The sites of intercalation within a native promoter sequence appear to be context and sequence dependent. The binding of one drug molecule influences the binding site of the second. Our structures underscore the fact that the DNA binding of a bis-intercalator is directional and different from the simple addition of two single intercalation sites. Our study suggests that improved XR5944 bis-intercalators targeting ERE may be designed through optimization of aminoalkyl linker and intercalation moieties at the weak binding sites.
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Affiliation(s)
- Clement Lin
- College of Pharmacy, University of Arizona, 1703 E. Mabel Street, Tucson, AZ 85721, USA
| | - Raveendra I Mathad
- College of Pharmacy, University of Arizona, 1703 E. Mabel Street, Tucson, AZ 85721, USA
| | - Zhenjiang Zhang
- College of Pharmacy, University of Arizona, 1703 E. Mabel Street, Tucson, AZ 85721, USA
| | - Neil Sidell
- Department of Gynecology and Obstetrics, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Danzhou Yang
- College of Pharmacy, University of Arizona, 1703 E. Mabel Street, Tucson, AZ 85721, USA Department of Chemistry, University of Arizona, Tucson, AZ 85721, USA BIO5 Institute, University of Arizona, Tucson, AZ 85721, USA The Arizona Cancer Center, Tucson, AZ 85724, USA
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DeGroot DE, Hayashi A, Denison MS. Lack of ligand-selective binding of the aryl hydrocarbon receptor to putative DNA binding sites regulating expression of Bax and paraoxonase 1 genes. Arch Biochem Biophys 2014; 541:13-20. [PMID: 24200861 PMCID: PMC3875388 DOI: 10.1016/j.abb.2013.10.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2013] [Revised: 10/25/2013] [Accepted: 10/28/2013] [Indexed: 12/29/2022]
Abstract
The aryl hydrocarbon receptor (AhR) is a ligand-dependent transcription factor that mediates the biological and toxicological effects of structurally diverse chemicals through its ability to bind specific DNA recognition sites (dioxin responsive elements (DREs)), and activate transcription of adjacent genes. While the DRE has a highly conserved consensus sequence, it has been suggested that the nucleotide specificity of AhR DNA binding may be ligand-dependent. The upstream regulatory regions of the murine Bax and human paraoxonase 1 (PON1) genes reportedly contain unique DRE-like sequences that respond to AhRs activated by some ligands but not others. Given the significant implications of this observation to understanding the diversity in AhR responses and that of other ligand-dependent nuclear receptors, a combination of DNA binding, nuclear translocation and gene expression analysis was used to investigate the molecular mechanisms underlying these ligand-selective responses. Although known AhR agonists stimulated AhR nuclear translocation, DRE binding and gene expression, the ligand-selective DRE-like DNA elements identified in the Bax and PON1 upstream regulatory regions failed to bind ligand-activated AhR or confer AhR-responsiveness upon a reporter gene. These results argue against the reported ligand-selectivity of AhR DNA binding and suggest DNA binding by ligand activated AhR involves DRE-containing DNA.
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Affiliation(s)
- Danica E DeGroot
- Department of Environmental Toxicology, University of California, Davis, CA 95616, United States
| | - Ai Hayashi
- Department of Environmental Toxicology, University of California, Davis, CA 95616, United States
| | - Michael S Denison
- Department of Environmental Toxicology, University of California, Davis, CA 95616, United States.
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de Souza FS, Franchini LF, Rubinstein M. Exaptation of transposable elements into novel cis-regulatory elements: is the evidence always strong? Mol Biol Evol 2013; 30:1239-51. [PMID: 23486611 PMCID: PMC3649676 DOI: 10.1093/molbev/mst045] [Citation(s) in RCA: 124] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Transposable elements (TEs) are mobile genetic sequences that can jump around the genome from one location to another, behaving as genomic parasites. TEs have been particularly effective in colonizing mammalian genomes, and such heavy TE load is expected to have conditioned genome evolution. Indeed, studies conducted both at the gene and genome levels have uncovered TE insertions that seem to have been co-opted--or exapted--by providing transcription factor binding sites (TFBSs) that serve as promoters and enhancers, leading to the hypothesis that TE exaptation is a major factor in the evolution of gene regulation. Here, we critically review the evidence for exaptation of TE-derived sequences as TFBSs, promoters, enhancers, and silencers/insulators both at the gene and genome levels. We classify the functional impact attributed to TE insertions into four categories of increasing complexity and argue that so far very few studies have conclusively demonstrated exaptation of TEs as transcriptional regulatory regions. We also contend that many genome-wide studies dealing with TE exaptation in recent lineages of mammals are still inconclusive and that the hypothesis of rapid transcriptional regulatory rewiring mediated by TE mobilization must be taken with caution. Finally, we suggest experimental approaches that may help attributing higher-order functions to candidate exapted TEs.
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Affiliation(s)
- Flávio S.J. de Souza
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular, Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
- Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Lucía F. Franchini
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular, Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | - Marcelo Rubinstein
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular, Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
- Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
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Song HY, Sun W, Prabhakar S, Aung KMM, Su X. Study sequence rules of estrogen receptor α–DNA interactions using dual polarization interferometry and computational modeling. Anal Biochem 2013; 433:121-8. [DOI: 10.1016/j.ab.2012.10.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Revised: 10/11/2012] [Accepted: 10/12/2012] [Indexed: 12/28/2022]
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Lawrence MG, Stephens CR, Need EF, Lai J, Buchanan G, Clements JA. Long terminal repeats act as androgen-responsive enhancers for the PSA-kallikrein locus. Endocrinology 2012; 153:3199-210. [PMID: 22597536 DOI: 10.1210/en.2012-1267] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The androgen receptor (AR) signaling pathway is a common therapeutic target for prostate cancer, because it is critical for the survival of both hormone-responsive and castrate-resistant tumor cells. Most of the detailed understanding that we have of AR transcriptional activation has been gained by studying classical target genes. For more than two decades, Kallikrein 3 (KLK3) (prostate-specific antigen) has been used as a prototypical AR target gene, because it is highly androgen responsive in prostate cancer cells. Three regions upstream of the KLK3 gene, including the distal enhancer, are known to contain consensus androgen-responsive elements required for AR-mediated transcriptional activation. Here, we show that KLK3 is one of a specific cluster of androgen-regulated genes at the centromeric end of the kallikrein locus with enhancers that evolved from the long terminal repeat (LTR) (LTR40a) of an endogenous retrovirus. Ligand-dependent recruitment of the AR to individual LTR-derived enhancers results in concurrent up-regulation of endogenous KLK2, KLK3, and KLKP1 expression in LNCaP prostate cancer cells. At the molecular level, a kallikrein-specific duplication within the LTR is required for maximal androgen responsiveness. Therefore, KLK3 represents a subset of target genes regulated by repetitive elements but is not typical of the whole spectrum of androgen-responsive transcripts. These data provide a novel and more detailed understanding of AR transcriptional activation and emphasize the importance of repetitive elements as functional regulatory units.
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Affiliation(s)
- Mitchell G Lawrence
- Australian Prostate Cancer Research Centre-Queensland, Institute of Health and Biomedical Innovation Queensland University of Technology, 60 Musk Avenue, Kelvin Grove, Queensland 4059, Australia
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Yang Q, Jian J, Katz S, Abramson SB, Huang X. 17β-Estradiol inhibits iron hormone hepcidin through an estrogen responsive element half-site. Endocrinology 2012; 153:3170-8. [PMID: 22535765 PMCID: PMC3380311 DOI: 10.1210/en.2011-2045] [Citation(s) in RCA: 136] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Interaction of estrogen with iron at the systemic level is long suspected, but direct evidence linking the two is limited. In the present study, we examined the effects of 17β-estradiol (E2) on hepcidin, a key negative regulator of iron absorption from the liver. We found that transcription of hepcidin was suppressed by E2 treatment in human liver HuH7 and HepG2 cells, and this down-regulation was blocked by E2 antagonist ICI 182780. Chromatin immunoprecipitation, deletion, and EMSA detected a functional estrogen responsive element half-site that is located between -2474 and -2462 upstream from the start of transcription of the hepcidin gene. After cloning the human hepcidin promoter into the pGL3Luc-Reporter vector, luciferase activity was also down-regulated by E2 treatment in HepG2 cells. E2 reduced hepcidin mRNA in wild-type mice as well as in hemochromatosis Fe gene knockout mice. In summary, our data suggest that hepcidin inhibition by E2 is to increase iron uptake, a mechanism to compensate iron loss during menstruation. This mechanism may also contribute to increased iron stores in oral contraceptive users.
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Affiliation(s)
- Qing Yang
- Department of Environmental Medicine, New York University School of Medicine, New York, New York 10016, USA
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Hüttemann M, Lee I, Gao X, Pecina P, Pecinova A, Liu J, Aras S, Sommer N, Sanderson TH, Tost M, Neff F, Aguilar-Pimentel JA, Becker L, Naton B, Rathkolb B, Rozman J, Favor J, Hans W, Prehn C, Puk O, Schrewe A, Sun M, Höfler H, Adamski J, Bekeredjian R, Graw J, Adler T, Busch DH, Klingenspor M, Klopstock T, Ollert M, Wolf E, Fuchs H, Gailus-Durner V, Hrabě de Angelis M, Weissmann N, Doan JW, Bassett DJP, Grossman LI. Cytochrome c oxidase subunit 4 isoform 2-knockout mice show reduced enzyme activity, airway hyporeactivity, and lung pathology. FASEB J 2012; 26:3916-30. [PMID: 22730437 DOI: 10.1096/fj.11-203273] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Cytochrome c oxidase (COX) is the terminal enzyme of the mitochondrial electron transport chain. The purpose of this study was to analyze the function of lung-specific cytochrome c oxidase subunit 4 isoform 2 (COX4i2) in vitro and in COX4i2-knockout mice in vivo. COX was isolated from cow lung and liver as control and functionally analyzed. COX4i2-knockout mice were generated and the effect of the gene knockout was determined, including COX activity, tissue energy levels, noninvasive and invasive lung function, and lung pathology. These studies were complemented by a comprehensive functional screen performed at the German Mouse Clinic (Neuherberg, Germany). We show that isolated cow lung COX containing COX4i2 is about twice as active (88 and 102% increased activity in the presence of allosteric activator ADP and inhibitor ATP, respectively) as liver COX, which lacks COX4i2. In COX4i2-knockout mice, lung COX activity and cellular ATP levels were significantly reduced (-50 and -29%, respectively). Knockout mice showed decreased airway responsiveness (60% reduced P(enh) and 58% reduced airway resistance upon challenge with 25 and 100 mg methacholine, respectively), and they developed a lung pathology deteriorating with age that included the appearance of Charcot-Leyden crystals. In addition, there was an interesting sex-specific phenotype, in which the knockout females showed reduced lean mass (-12%), reduced total oxygen consumption rate (-8%), improved glucose tolerance, and reduced grip force (-14%) compared to wild-type females. Our data suggest that high activity lung COX is a central determinant of airway function and is required for maximal airway responsiveness and healthy lung function. Since airway constriction requires energy, we propose a model in which reduced tissue ATP levels explain protection from airway hyperresponsiveness, i.e., absence of COX4i2 leads to reduced lung COX activity and ATP levels, which results in impaired airway constriction and thus reduced airway responsiveness; long-term lung pathology develops in the knockout mice due to impairment of energy-costly lung maintenance processes; and therefore, we propose mitochondrial oxidative phosphorylation as a novel target for the treatment of respiratory diseases, such as asthma.
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Affiliation(s)
- Maik Hüttemann
- Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, MI 48201, USA.
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Nuclear receptor HNF4α binding sequences are widespread in Alu repeats. BMC Genomics 2011; 12:560. [PMID: 22085832 PMCID: PMC3252374 DOI: 10.1186/1471-2164-12-560] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2011] [Accepted: 11/15/2011] [Indexed: 12/04/2022] Open
Abstract
Background Alu repeats, which account for ~10% of the human genome, were originally considered to be junk DNA. Recent studies, however, suggest that they may contain transcription factor binding sites and hence possibly play a role in regulating gene expression. Results Here, we show that binding sites for a highly conserved member of the nuclear receptor superfamily of ligand-dependent transcription factors, hepatocyte nuclear factor 4alpha (HNF4α, NR2A1), are highly prevalent in Alu repeats. We employ high throughput protein binding microarrays (PBMs) to show that HNF4α binds > 66 unique sequences in Alu repeats that are present in ~1.2 million locations in the human genome. We use chromatin immunoprecipitation (ChIP) to demonstrate that HNF4α binds Alu elements in the promoters of target genes (ABCC3, APOA4, APOM, ATPIF1, CANX, FEMT1A, GSTM4, IL32, IP6K2, PRLR, PRODH2, SOCS2, TTR) and luciferase assays to show that at least some of those Alu elements can modulate HNF4α-mediated transactivation in vivo (APOM, PRODH2, TTR, APOA4). HNF4α-Alu elements are enriched in promoters of genes involved in RNA processing and a sizeable fraction are in regions of accessible chromatin. Comparative genomics analysis suggests that there may have been a gain in HNF4α binding sites in Alu elements during evolution and that non Alu repeats, such as Tiggers, also contain HNF4α sites. Conclusions Our findings suggest that HNF4α, in addition to regulating gene expression via high affinity binding sites, may also modulate transcription via low affinity sites in Alu repeats.
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CBP mediates NF-κB-dependent histone acetylation and estrogen receptor recruitment to an estrogen response element in the BIRC3 promoter. Mol Cell Biol 2011; 32:569-75. [PMID: 22083956 DOI: 10.1128/mcb.05869-11] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Estrogen receptor (ER) and NF-κB are transcription factors with profound effects on breast cancer cell proliferation and survival. While many studies demonstrate that ER and NF-κB can repress each other, we previously identified a gene signature that is synergistically upregulated by these two factors in more aggressive luminal B breast tumors. Herein, we examine a novel mechanism of cross talk between ER and NF-κB that results in the upregulation of the antiapoptotic gene BIRC3 (also known as cIAP2). We demonstrate that NF-κB, acting through two response elements, is required for ER recruitment to an adjacent estrogen response element (ERE) in the BIRC3 promoter. This effect is accompanied by a major increase in NF-κB-dependent histone acetylation around the ERE. Interestingly, CBP, a histone acetyltransferase previously implicated in repressive interactions between ER and NF-κB, plays a permissive role by promoting histone acetylation and ER recruitment, as well as enhanced expression of BIRC3. These findings suggest a new gene regulatory mechanism by which inflammation and NF-κB activation can influence ER recruitment to inherently inactive ER binding sites. This fine-tuning mechanism may explain how two factors that generally repress each other's activity may work together on certain genes to promote breast cancer cell survival and tumor progression.
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Sidell N, Mathad RI, Shu FJ, Zhang Z, Kallen CB, Yang D. Intercalation of XR5944 with the estrogen response element is modulated by the tri-nucleotide spacer sequence between half-sites. J Steroid Biochem Mol Biol 2011; 124:121-7. [PMID: 21333738 PMCID: PMC3072055 DOI: 10.1016/j.jsbmb.2011.02.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2010] [Revised: 02/04/2011] [Accepted: 02/05/2011] [Indexed: 12/21/2022]
Abstract
DNA-intercalating molecules can impair DNA replication, DNA repair, and gene transcription. We previously demonstrated that XR5944, a DNA bis-intercalator, specifically blocks binding of estrogen receptor-α (ERα) to the consensus estrogen response element (ERE). The consensus ERE sequence is AGGTCAnnnTGACCT, where nnn is known as the tri-nucleotide spacer. Recent work has shown that the tri-nucleotide spacer can modulate ERα-ERE binding affinity and ligand-mediated transcriptional responses. To further understand the mechanism by which XR5944 inhibits ERα-ERE binding, we tested its ability to interact with consensus EREs with variable tri-nucleotide spacer sequences and with natural but non-consensus ERE sequences using one dimensional nuclear magnetic resonance (1D (1)H NMR) titration studies. We found that the tri-nucleotide spacer sequence significantly modulates the binding of XR5944 to EREs. Of the sequences that were tested, EREs with CGG and AGG spacers showed the best binding specificity with XR5944, while those spaced with TTT demonstrated the least specific binding. The binding stoichiometry of XR5944 with EREs was 2:1, which can explain why the spacer influences the drug-DNA interaction; each XR5944 spans four nucleotides (including portions of the spacer) when intercalating with DNA. To validate our NMR results, we conducted functional studies using reporter constructs containing consensus EREs with tri-nucleotide spacers CGG, CTG, and TTT. Results of reporter assays in MCF-7 cells indicated that XR5944 was significantly more potent in inhibiting the activity of CGG- than TTT-spaced EREs, consistent with our NMR results. Taken together, these findings predict that the anti-estrogenic effects of XR5944 will depend not only on ERE half-site composition but also on the tri-nucleotide spacer sequence of EREs located in the promoters of estrogen-responsive genes.
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Affiliation(s)
- Neil Sidell
- Department of Gynecology & Obstetrics, Emory University School of Medicine, Atlanta, GA
| | | | - Feng-jue Shu
- Department of Gynecology & Obstetrics, Emory University School of Medicine, Atlanta, GA
| | | | - Caleb B. Kallen
- Department of Gynecology & Obstetrics, Emory University School of Medicine, Atlanta, GA
| | - Danzhou Yang
- College of Pharmacy, The University of Arizona, Tucson, AZ
- Arizona Cancer Center, The University of Arizona, Tucson, AZ
- BIO5 Institute, The University of Arizona, Tucson, AZ
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Estrogen receptor signaling and its relationship to cytokines in systemic lupus erythematosus. J Biomed Biotechnol 2010; 2010:317452. [PMID: 20617147 PMCID: PMC2896666 DOI: 10.1155/2010/317452] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2010] [Revised: 03/18/2010] [Accepted: 03/31/2010] [Indexed: 01/19/2023] Open
Abstract
Dysregulation of cytokines is among the main abnormalities in Systemic Lupus Erythematosus (SLE). However, although, estrogens, which are known to be involved in lupus disease,
influence cytokine production, the underlying molecular mechanisms remain poorly defined.
Recent evidence demonstrates the presence of estrogen receptor in various cell types of the
immune system, while divergent effects of estrogens on the cytokine regulation are thought to be
implicated. In this paper, we provide an overview of the current knowledge as to how estrogen-induced
modulation of cytokine production in SLE is mediated by the estrogen receptor while
simultaneously clarifying various aspects of estrogen receptor signaling in this disease. The
estrogen receptor subtypes, their structure, and the mode of action of estrogens by gene activation
and via extranuclear effects are briefly presented. Results regarding the possible correlation
between estrogen receptor gene polymorphisms and quantitative changes in the receptor protein
to SLE pathology and cytokine production are reviewed.
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Shu FJ, Sidell N, Yang D, Kallen CB. The tri-nucleotide spacer sequence between estrogen response element half-sites is conserved and modulates ERalpha-mediated transcriptional responses. J Steroid Biochem Mol Biol 2010; 120:172-9. [PMID: 20403436 PMCID: PMC2891080 DOI: 10.1016/j.jsbmb.2010.04.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2010] [Revised: 04/10/2010] [Accepted: 04/12/2010] [Indexed: 12/17/2022]
Abstract
The estrogen response element (ERE) consensus sequence is AGGTCAnnnTGACCT, where nnn is known as the tri-nucleotide spacer sequence. Studying 1017 high-confidence ERalpha-bound loci, we found that genomic EREs are enriched for spacers composed of C(A/T)G, suggesting that the spacer may influence receptor binding and transcriptional responses. We designed consensus EREs containing variable spacer sequences and compared ERalpha binding in gel shift assays and enhancer function in reporter assays. We found that ERalpha-ERE binding affinity is modulated by the tri-nucleotide spacer sequence and is favored by spacer sequences of CTG>GCC>TTT. Similarly, luciferase reporter assays indicated that the estrogen-stimulated transcriptional response is modulated by the spacer and parallels the gel shift data: CTG>GCC>TTT. Reporter assays demonstrated that the spacer sequence also modulates the sensitivity of EREs to repression engendered by the receptor antagonist hydroxytamoxifen. These experiments indicate that the sequence of the tri-nucleotide spacer is non-random at receptor-bound genomic loci, influences ERalpha-DNA-binding affinity, and modulates transactivation potential of the receptor-ligand-DNA complex. This work has implications for understanding which genomic EREs are targeted by ERalpha, should improve computational prediction of functional EREs within genomic sequences, and describes novel sequence determinants of the estrogen response.
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Affiliation(s)
- Feng-jue Shu
- Department of Gynecology and Obstetrics, Emory University School of Medicine, 1639 Pierce Drive, WMB 4217, Atlanta, GA, USA, 30322
| | - Neil Sidell
- Department of Gynecology and Obstetrics, Emory University School of Medicine, 1639 Pierce Drive, WMB 4217, Atlanta, GA, USA, 30322
- Corresponding Authors: Caleb B. Kallen, Department of Gynecology and Obstetrics, Emory University School of Medicine, 1639 Pierce Drive, WMB 4217, Atlanta, GA 30322. Phone: 404-727-4047, Fax: 404-727-8609, or Neil Sidell, same address, Phone: 404-727-9155, Fax: 404-727-8609,
| | - Danzhou Yang
- Department of Pharmacology and Toxicology, College of Pharmacy, The University of Arizona, 1703 E Mabel St, Tucson, AZ, USA, 85721
| | - Caleb B. Kallen
- Department of Gynecology and Obstetrics, Emory University School of Medicine, 1639 Pierce Drive, WMB 4217, Atlanta, GA, USA, 30322
- Corresponding Authors: Caleb B. Kallen, Department of Gynecology and Obstetrics, Emory University School of Medicine, 1639 Pierce Drive, WMB 4217, Atlanta, GA 30322. Phone: 404-727-4047, Fax: 404-727-8609, or Neil Sidell, same address, Phone: 404-727-9155, Fax: 404-727-8609,
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