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Kim DS, Camacho CV, Setlem R, Kim K, Malladi S, Hou TY, Nandu T, Gadad SS, Kraus WL. Functional Characterization of lncRNA152 as an Angiogenesis-Inhibiting Tumor Suppressor in Triple-Negative Breast Cancers. Mol Cancer Res 2022; 20:1623-1635. [PMID: 35997635 PMCID: PMC9633386 DOI: 10.1158/1541-7786.mcr-22-0123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 07/04/2022] [Accepted: 08/19/2022] [Indexed: 11/16/2022]
Abstract
Long noncoding RNAs have been implicated in many of the hallmarks of cancer. Herein, we found that the expression of lncRNA152 (lnc152; a.k.a. DRAIC), which we annotated previously, is highly upregulated in luminal breast cancer (LBC) and downregulated in triple-negative breast cancer (TNBC). Knockdown of lnc152 promotes cell migration and invasion in LBC cell lines. In contrast, ectopic expression of lnc152 inhibits growth, migration, invasion, and angiogenesis in TNBC cell lines. In mice, lnc152 inhibited the growth of TNBC cell xenografts, as well as metastasis of TNBC cells in an intracardiac injection model. Transcriptome analysis of the xenografts indicated that lnc152 downregulates genes controlling angiogenesis. Using pull down assays followed by LC/MS-MS, we identified RBM47, a known tumor suppressor in breast cancer, as a lnc152-interacting protein. The effects of lnc152 in TNBC cells are mediated, in part, by regulating the expression of RBM47. Collectively, our results demonstrate that lnc152 is an angiogenesis-inhibiting tumor suppressor that attenuates the aggressive cancer-related phenotypes found in TNBC. IMPLICATIONS This study identifies lncRNA152 as an angiogenesis-inhibiting tumor suppressor that attenuates the aggressive cancer-related phenotypes found in TNBC by upregulating the expression of the tumor suppressor RBM47. As such, lncRNA152 may serve as a biomarker to track aggressiveness of breast cancer, as well as therapeutic target for treating TNBC.
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Affiliation(s)
- Dae-Seok Kim
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- Division of Basic Research, Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- Current address: Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- These authors contributed equally to this work
| | - Cristel V. Camacho
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- Division of Basic Research, Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- These authors contributed equally to this work
| | - Rohit Setlem
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- Division of Basic Research, Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Kangsan Kim
- Department of Pathology, Harold C. Simmons Comprehensive Cancer Center, UT Southwestern Medical Center, Dallas, TX, USA
| | - Srinivas Malladi
- Department of Pathology, Harold C. Simmons Comprehensive Cancer Center, UT Southwestern Medical Center, Dallas, TX, USA
| | - Tim Y. Hou
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- Division of Basic Research, Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Tulip Nandu
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- Division of Basic Research, Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Shrikanth S. Gadad
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- Division of Basic Research, Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- Center of Emphasis in Cancer, Department of Molecular and Translational Medicine, Texas Tech University Health Sciences Center El Paso, TX 79905, USA
| | - W. Lee Kraus
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- Division of Basic Research, Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
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Hou TY, Kraus WL. Analysis of estrogen-regulated enhancer RNAs identifies a functional motif required for enhancer assembly and gene expression. Cell Rep 2022; 39:110944. [PMID: 35705040 PMCID: PMC9246336 DOI: 10.1016/j.celrep.2022.110944] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 04/12/2022] [Accepted: 05/20/2022] [Indexed: 11/03/2022] Open
Abstract
To better understand the functions of non-coding enhancer RNAs (eRNAs), we annotated the estrogen-regulated eRNA transcriptome in estrogen receptor α (ERα)-positive breast cancer cells using PRO-cap and RNA sequencing. We then cloned a subset of the eRNAs identified, fused them to single guide RNAs, and targeted them to their ERα enhancers of origin using CRISPR/dCas9. Some of the eRNAs tested modulated the expression of cognate, but not heterologous, target genes after estrogen treatment by increasing ERα recruitment and stimulating p300-catalyzed H3K27 acetylation at the enhancer. We identified a ∼40 nucleotide functional eRNA regulatory motif (FERM) present in many eRNAs that was necessary and sufficient to modulate gene expression, but not the specificity of activation, after estrogen treatment. The FERM interacted with BCAS2, an RNA-binding protein amplified in breast cancers. The ectopic expression of a targeted eRNA controlling the expression of an oncogene resulted in increased cell proliferation, demonstrating the regulatory potential of eRNAs in breast cancer.
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Affiliation(s)
- Tim Y Hou
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA; Division of Basic Research, Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - W Lee Kraus
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA; Division of Basic Research, Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA.
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Duffield GE, Robles-Murguia M, Hou TY, McDonald KA. Targeted Disruption of the Inhibitor of DNA Binding 4 ( Id4) Gene Alters Photic Entrainment of the Circadian Clock. Int J Mol Sci 2021; 22:9632. [PMID: 34502541 PMCID: PMC8431790 DOI: 10.3390/ijms22179632] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 08/22/2021] [Accepted: 08/29/2021] [Indexed: 11/16/2022] Open
Abstract
Inhibitor of DNA binding (Id) genes comprise a family of four helix-loop-helix (HLH) transcriptional inhibitors. Our earlier studies revealed a role for ID2 within the circadian system, contributing to input, output, and core clock function through its interaction with CLOCK and BMAL1. Here, we explore the contribution of ID4 to the circadian system using a targeted disruption of the Id4 gene. Attributes of the circadian clock were assessed by monitoring the locomotor activity of Id4-/- mice, and they revealed disturbances in its operation. Id4-mutant mice expressed a shorter circadian period length, attenuated phase shifts in responses to continuous and discrete photic cues, and an advanced phase angle of entrainment under a 12:12 light:dark cycle and under short and long photoperiods. To understand the basis for these properties, suprachiasmatic nucleus (SCN) and retinal structures were examined. Anatomical analysis reveals a smaller Id4-/- SCN in the width dimension, which is a finding consistent with its smaller brain. As a result of this feature, anterograde tracing in Id4-/- mice revealed retinal afferents innovate a disproportionally larger SCN area. The Id4-/- photic entrainment responses are unlikely to be due to an impaired function of the retinal pathways since Id4-/- retinal anatomy and function tested by pupillometry were similar to wild-type mice. Furthermore, these circadian characteristics are opposite to those exhibited by the Id2-/- mouse, suggesting an opposing influence of the ID4 protein within the circadian system; or, the absence of ID4 results in changes in the expression or activity of other members of the Id gene family. Expression analysis of the Id genes within the Id4-/- SCN revealed a time-of-day specific elevated Id1. It is plausible that the increased Id1 and/or absence of ID4 result in changes in interactions with bHLH canonical clock components or with targets upstream and/or downstream of the clock, thereby resulting in abnormal properties of the circadian clock and its entrainment.
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Affiliation(s)
- Giles E. Duffield
- Department of Biological Sciences, Galvin Life Science Center, University of Notre Dame, Notre Dame, IN 46556, USA; (M.R.-M.); (T.Y.H.); (K.A.M.)
- Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Maricela Robles-Murguia
- Department of Biological Sciences, Galvin Life Science Center, University of Notre Dame, Notre Dame, IN 46556, USA; (M.R.-M.); (T.Y.H.); (K.A.M.)
- Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Tim Y. Hou
- Department of Biological Sciences, Galvin Life Science Center, University of Notre Dame, Notre Dame, IN 46556, USA; (M.R.-M.); (T.Y.H.); (K.A.M.)
| | - Kathleen A. McDonald
- Department of Biological Sciences, Galvin Life Science Center, University of Notre Dame, Notre Dame, IN 46556, USA; (M.R.-M.); (T.Y.H.); (K.A.M.)
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Hou TY, Kraus WL. Come one, come all? Re-evaluating RNA polymerase II pre-initiation complex assembly using single-molecule microscopy. Mol Cell 2021; 81:3443-3445. [PMID: 34478651 DOI: 10.1016/j.molcel.2021.08.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Complementary papers by Nguyen et al. (2021) and Baek et al. (2021) track the assembly of the pre-initiation complexes at gene promoters using single-molecule microscopy, revealing dynamic spatiotemporal regulation of transcription initiation.
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Affiliation(s)
- Tim Y Hou
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Division of Basic Research, Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - W Lee Kraus
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Division of Basic Research, Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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5
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Duffield GE, Han S, Hou TY, de la Iglesia HO, McDonald KA, Mecklenburg KL, Robles-Murguia M. Inhibitor of DNA binding 2 (Id2) Regulates Photic Entrainment Responses in Mice: Differential Responses of the Id2-/- Mouse Circadian System Are Dependent on Circadian Phase and on Duration and Intensity of Light. J Biol Rhythms 2020; 35:555-575. [PMID: 32981454 DOI: 10.1177/0748730420957504] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
ID2 is a rhythmically expressed helix-loop-helix transcriptional repressor, and its deletion results in abnormal properties of photoentrainment. By examining parametric and nonparametric models of entrainment, we have started to explore the mechanism underlying this circadian phenotype. Id2-/- mice were exposed to differing photoperiods, and the phase angle of entrainment under short days was delayed 2 h as compared with controls. When exposed to long durations of continuous light, enhanced entrainment responses were observed after a delay of the clock but not with phase advances. However, the magnitude of phase shifts was not different in Id2-/- mice tested in constant darkness using a discrete pulse of saturating light. No differences were observed in the speed of clock resetting when challenged by a series of discrete pulses interspaced by varying time intervals. A photic phase-response curve was constructed, although no genotypic differences were observed. Although phase shifts produced by discrete saturating light pulses at CT16 were similar, treatment with a subsaturating pulse revealed a ~2-fold increase in the magnitude of the Id2-/- shift. A corresponding elevation of light-induced per1 expression was observed in the Id2-/- suprachiasmatic nucleus (SCN). To test whether the phenotype is based on a sensitivity change at the level of the retina, pupil constriction responses were measured. No differences were observed in responses or in retinal histology, suggesting that the phenotype occurs downstream of the retina and retinal hypothalamic tract. To test whether the phenotype is due to a reduced amplitude of state variables of the clock, the expression of clock genes per1 and per2 was assessed in vivo and in SCN tissue explants. Amplitude, phase, and period length were normal in Id2-/- mice. These findings suggest that ID2 contributes to a photoregulatory mechanism at the level of the SCN central pacemaker through control of the photic induction of negative elements of the clock.
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Affiliation(s)
- Giles E Duffield
- Department of Biological Sciences, Galvin Life Science Center, University of Notre Dame, Notre Dame, Indiana.,Eck Institute for Global Health, University of Notre Dame, Notre Dame, Indiana
| | - Sung Han
- Department of Biology and Graduate Program in Neuroscience, University of Washington, Seattle, Washington
| | - Tim Y Hou
- Department of Biological Sciences, Galvin Life Science Center, University of Notre Dame, Notre Dame, Indiana
| | - Horacio O de la Iglesia
- Department of Biology and Graduate Program in Neuroscience, University of Washington, Seattle, Washington
| | - Kathleen A McDonald
- Department of Biological Sciences, Galvin Life Science Center, University of Notre Dame, Notre Dame, Indiana
| | - Kirk L Mecklenburg
- Department of Biology, Indiana University South Bend, South Bend, Indiana
| | - Maricela Robles-Murguia
- Department of Biological Sciences, Galvin Life Science Center, University of Notre Dame, Notre Dame, Indiana.,Eck Institute for Global Health, University of Notre Dame, Notre Dame, Indiana
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Hou TY, Kraus WL. Spirits in the Material World: Enhancer RNAs in Transcriptional Regulation. Trends Biochem Sci 2020; 46:138-153. [PMID: 32888773 DOI: 10.1016/j.tibs.2020.08.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Revised: 08/04/2020] [Accepted: 08/07/2020] [Indexed: 12/15/2022]
Abstract
Responses to developmental and environmental cues depend on precise spatiotemporal control of gene transcription. Enhancers, which comprise DNA elements bound by regulatory proteins, can activate target genes in response to these external signals. Recent studies have shown that enhancers are transcribed to produce enhancer RNAs (eRNAs). Do eRNAs play a functional role in activating gene expression or are they non-functional byproducts of nearby transcription machinery? The unstable nature of eRNAs and over-reliance on knockdown approaches have made elucidating the possible functions of eRNAs challenging. We focus here on studies using cloned eRNAs to study their function as transcripts, revealing roles for eRNAs in enhancer-promoter looping, recruiting transcriptional machinery, and facilitating RNA polymerase pause-release to regulate gene expression.
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Affiliation(s)
- Tim Y Hou
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Division of Basic Research, Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - W Lee Kraus
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Division of Basic Research, Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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Hou TY, Nandu T, Li R, Chae M, Murakami S, Kraus WL. Characterization of basal and estrogen-regulated antisense transcription in breast cancer cells: Role in regulating sense transcription. Mol Cell Endocrinol 2020; 506:110746. [PMID: 32035111 PMCID: PMC7089808 DOI: 10.1016/j.mce.2020.110746] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 02/01/2020] [Accepted: 02/01/2020] [Indexed: 12/27/2022]
Abstract
Estrogen-responsive breast cancer cells exhibit both basal and estrogen-regulated transcriptional programs, which lead to the transcription of many different transcription units (i.e., genes), including those that produce coding and non-coding sense (e.g., mRNA, lncRNA) and antisense (i.e., asRNA) transcripts. We have previously characterized the global basal and estrogen-regulated transcriptomes in estrogen receptor alpha (ERα)-positive MCF-7 breast cancer cells. Herein, we have mined genomic data to define three classes of antisense transcription in MCF-7 cells based on where their antisense transcription termination sites reside relative to their cognate sense mRNA and lncRNA genes. These three classes differ in their response to estrogen treatment, the enrichment of a number of genomic features associated with active promoters (H3K4me3, RNA polymerase II, open chromatin architecture), and the biological functions of their cognate sense genes as analyzed by DAVID gene ontology. We further characterized two estrogen-regulated antisense transcripts arising from the MYC gene in MCF-7 cells, showing that these antisense transcripts are 5'-capped, 3'-polyadenylated, and localized to different compartments of the cell. Together, our analyses have revealed distinct classes of antisense transcription correlated to different biological processes and response to estrogen stimulation, uncovering another layer of hormone-regulated gene regulation.
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Affiliation(s)
- Tim Y Hou
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA; Division of Basic Research, Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Tulip Nandu
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA; Division of Basic Research, Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Rui Li
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA; Division of Basic Research, Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA; Program in Genetics, Development and Disease, Graduate School of Biomedical Sciences, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Minho Chae
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA; Division of Basic Research, Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Shino Murakami
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA; Division of Basic Research, Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA; Program in Genetics, Development and Disease, Graduate School of Biomedical Sciences, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - W Lee Kraus
- Laboratory of Signaling and Gene Regulation, Cecil H. and Ida Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA; Division of Basic Research, Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA; Program in Genetics, Development and Disease, Graduate School of Biomedical Sciences, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA.
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Hou TY, Kraus WL. Abstract P1-05-02: Estrogen-regulated enhancer RNAs control enhancer assembly and function in breast cancer cells. Cancer Res 2020. [DOI: 10.1158/1538-7445.sabcs19-p1-05-02] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Approximately 70% of breast cancers express estrogen receptor alpha (ERα), a hormone-regulated transcription factor, making it an excellent target for endocrine therapy. When endogenous and exogenous ligands engage ERα, the receptor binds to regulatory regions in the genome known as enhancers, where it (1) associates with coregulatory proteins, (2) increases histone modifications associated with active enhancers, (3) promotes chromatin looping, (4) stimulates enhancer transcription and the production of enhancer RNAs (eRNAs), and (5) ultimately regulates target gene transcription. We have previously used global run-on sequencing (GRO-seq), a high-throughput method that identifies the location and orientation of all transcriptionally active RNA polymerases across the genome, to identify active enhancers based on enhancer transcription and enrichment of the aforementioned genomic features. In ERα-positive breast cancer cells, estrogen signaling promotes the synthesis of thousands of eRNAs that originate from ERα enhancers. We are interested in understanding the functions of these estrogen-regulated eRNAs and how they contribute to the etiology of breast cancer.
Recent studies on the roles of eRNAs have suggested that they may (1) recruit regulatory proteins to enhancers; (2) promote RNA polymerase II transition; (3) regulate histone modification; and (4) increase chromosome looping. One challenge facing the field is the lack of accurate eRNA annotations and cloned full-length eRNAs; eRNAs have typically been studied as signals from genomic assays on browser tracks, not as physical entities (e.g., cDNAs) - in other words, “ghosts.” We have employed precision nuclear run-on of capped RNA (PRO-cap) to determine the transcription start sites of all expressed eRNAs. In addition, we have also used ultra-deep RNA-sequencing of polyA-depleted and polyA-enriched RNA fractions to detect eRNAs and examine for the potential splicing of eRNAs. Combining these genomic data, our annotations provide critical information for the large-scale cloning of eRNAs and testing them either by (1) tethering them to their cognate ERα enhancers by using CRISPR/dCas9 technology (i.e., cis) or (2) ectopically expressing them (i.e., trans) in MCF-7 breast cancer cells. When we tether eRNAs to their cognate ERα enhancers by using dCas9 and CRISPR guide RNAs, various aspects of ERα enhancer assembly and target gene expression are enhanced. Currently we are devising strategies to screen for functional eRNAs on a genome-wide basis to determine how they contribute to ERα enhancer assembly and function on a global scale, and ultimately identify the eRNAs that drive breast cancer initiation and growth.
This work is supported by grants from the NIH/NIDDK (DK058110) and CPRIT (RP160319) to W.L.K.
Citation Format: Tim Y Hou, William L Kraus. Estrogen-regulated enhancer RNAs control enhancer assembly and function in breast cancer cells [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P1-05-02.
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Affiliation(s)
- Tim Y Hou
- University of Texas Southwestern Medical Center, Dallas, TX
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Hou TY, Davidson LA, Kim E, Fan YY, Fuentes NR, Triff K, Chapkin RS. Nutrient-Gene Interaction in Colon Cancer, from the Membrane to Cellular Physiology. Annu Rev Nutr 2017; 36:543-70. [PMID: 27431370 DOI: 10.1146/annurev-nutr-071715-051039] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The International Agency for Research on Cancer recently released an assessment classifying red and processed meat as "carcinogenic to humans" on the basis of the positive association between increased consumption and risk for colorectal cancer. Diet, however, can also decrease the risk for colorectal cancer and be used as a chemopreventive strategy. Bioactive dietary molecules, such as n-3 polyunsaturated fatty acids, curcumin, and fermentable fiber, have been proposed to exert chemoprotective effects, and their molecular mechanisms have been the focus of research in the dietary/chemoprevention field. Using these bioactives as examples, this review surveys the proposed mechanisms by which they exert their effects, from the nucleus to the cellular membrane. In addition, we discuss emerging technologies involving the culturing of colonic organoids to study the physiological effects of dietary bioactives. Finally, we address future challenges to the field regarding the identification of additional molecular mechanisms and other bioactive dietary molecules that can be utilized in our fight to reduce the incidence of colorectal cancer.
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Affiliation(s)
- Tim Y Hou
- Program in Integrative Nutrition and Complex Diseases, Texas A&M University, College Station, Texas 77843; .,Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas 77843
| | - Laurie A Davidson
- Program in Integrative Nutrition and Complex Diseases, Texas A&M University, College Station, Texas 77843; .,Department of Nutrition and Food Science, Texas A&M University, College Station, Texas 77843.,Center for Translational Environmental Health Research, Texas A&M University, College Station, Texas 77843
| | - Eunjoo Kim
- Program in Integrative Nutrition and Complex Diseases, Texas A&M University, College Station, Texas 77843; .,Department of Molecular and Cellular Medicine, Texas A&M University, College Station, Texas 77843
| | - Yang-Yi Fan
- Program in Integrative Nutrition and Complex Diseases, Texas A&M University, College Station, Texas 77843; .,Department of Nutrition and Food Science, Texas A&M University, College Station, Texas 77843
| | - Natividad R Fuentes
- Program in Integrative Nutrition and Complex Diseases, Texas A&M University, College Station, Texas 77843; .,Faculty of Toxicology, Texas A&M University, College Station, Texas 77843
| | - Karen Triff
- Program in Integrative Nutrition and Complex Diseases, Texas A&M University, College Station, Texas 77843;
| | - Robert S Chapkin
- Program in Integrative Nutrition and Complex Diseases, Texas A&M University, College Station, Texas 77843; .,Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas 77843.,Department of Nutrition and Food Science, Texas A&M University, College Station, Texas 77843.,Faculty of Toxicology, Texas A&M University, College Station, Texas 77843.,Center for Translational Environmental Health Research, Texas A&M University, College Station, Texas 77843
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Hou TY, McMurray DN, Chapkin RS. Omega-3 fatty acids, lipid rafts, and T cell signaling. Eur J Pharmacol 2015; 785:2-9. [PMID: 26001374 DOI: 10.1016/j.ejphar.2015.03.091] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2015] [Revised: 02/16/2015] [Accepted: 03/16/2015] [Indexed: 12/24/2022]
Abstract
n-3 polyunsaturated fatty acids (PUFA) have been shown in many clinical studies to attenuate inflammatory responses. Although inflammatory responses are orchestrated by a wide spectrum of cells, CD4(+) T cells play an important role in the etiology of many chronic inflammatory diseases such as inflammatory bowel disease and obesity. In light of recent concerns over the safety profiles of non-steroidal anti-inflammatory drugs (NSAIDs), alternatives such as bioactive nutraceuticals are becoming more attractive. In order for these agents to be accepted into mainstream medicine, however, the mechanisms by which nutraceuticals such as n-3 PUFA exert their anti-inflammatory effects must be fully elucidated. Lipid rafts are nanoscale, dynamic domains in the plasma membrane that are formed through favorable lipid-lipid (cholesterol, sphingolipids, and saturated fatty acids) and lipid-protein (membrane-actin cytoskeleton) interactions. These domains optimize the clustering of signaling proteins at the membrane to facilitate efficient cell signaling which is required for CD4(+) T cell activation and differentiation. This review summarizes novel emerging data documenting the ability of n-3 PUFA to perturb membrane-cytoskeletal structure and function in CD4(+) T cells. An understanding of these underlying mechanisms will provide a rationale for the use of n-3 PUFA in the treatment of chronic inflammation.
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Affiliation(s)
- Tim Y Hou
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, USA; Department of Nutrition and Food Science, Texas A&M University, College Station, TX, USA; Program in Integrative Nutrition and Complex Diseases, Texas A&M University, College Station, TX, USA
| | - David N McMurray
- Department of Nutrition and Food Science, Texas A&M University, College Station, TX, USA; Program in Integrative Nutrition and Complex Diseases, Texas A&M University, College Station, TX, USA; Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA; Department of Microbial Pathogenesis and Immunology, Texas A&M University System Health Science Center, College Station, TX, USA
| | - Robert S Chapkin
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, USA; Department of Nutrition and Food Science, Texas A&M University, College Station, TX, USA; Program in Integrative Nutrition and Complex Diseases, Texas A&M University, College Station, TX, USA; Center for Translational Environmental Health Research, Texas A&M University, College Station, TX, USA; Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA; Department of Microbial Pathogenesis and Immunology, Texas A&M University System Health Science Center, College Station, TX, USA.
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11
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Allen MJ, Fan YY, Monk JM, Hou TY, Barhoumi R, McMurray DN, Chapkin RS. n-3 PUFAs reduce T-helper 17 cell differentiation by decreasing responsiveness to interleukin-6 in isolated mouse splenic CD4⁺ T cells. J Nutr 2014; 144:1306-13. [PMID: 24944284 PMCID: PMC4093987 DOI: 10.3945/jn.114.194407] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Cluster of differentiation 4(+) (CD4(+)) effector T-cell subsets [e.g., T-helper (Th) 1 and Th17] are implicated in autoimmune and inflammatory disorders such as multiple sclerosis, psoriasis, and rheumatoid arthritis. Interleukin (IL)-6 is a pleiotropic cytokine that induces Th17 polarization via signaling through the membrane-bound transducer glycoprotein 130 (GP130). Previously, we demonstrated that n-3 (ω-3) polyunsaturated fatty acids (PUFAs) reduce CD4(+) T-cell activation and differentiation into pathogenic Th17 cells by 25-30%. Here we report that n-3 PUFAs alter the response of CD4(+) T cells to IL-6 in a lipid raft membrane-dependent manner. Naive splenic CD4(+) T cells from fat-1 transgenic mice exhibited 30% lower surface expression of the IL-6 receptor. This membrane-bound receptor is known to be shed during cellular activation, but the release of soluble IL-6 receptor after treatment with anti-CD3 and anti-CD28 was not changed in the CD4(+) T cells from fat-1 mice, suggesting that the decrease in surface expression was not due to ectodomain release. We observed a significant 20% decrease in the association of GP130 with lipid rafts in activated fat-1 CD4(+) T cells and a 35% reduction in GP130 homodimerization, an obligate requirement for downstream signaling. The phosphorylation of signal transducer and activator of transcription 3 (STAT3), a downstream target of IL-6-dependent signaling, was also decreased by 30% in response to exogenous IL-6 in fat-1 CD4(+) T cells. Our results suggest that n-3 PUFAs suppress Th17 cell differentiation in part by reducing membrane raft-dependent responsiveness to IL-6, an essential polarizing cytokine.
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Affiliation(s)
- M. Jeannie Allen
- Program in Integrative Nutrition and Complex Diseases,,Nutrition and Food Science
| | - Yang-Yi Fan
- Program in Integrative Nutrition and Complex Diseases,,Nutrition and Food Science
| | - Jennifer M. Monk
- Program in Integrative Nutrition and Complex Diseases,,Nutrition and Food Science
| | - Tim Y. Hou
- Program in Integrative Nutrition and Complex Diseases,,Biochemistry and Biophysics
| | - Rola Barhoumi
- College of Veterinary Medicine and Biomedical Sciences Image Analysis Laboratory, and
| | - David N. McMurray
- Program in Integrative Nutrition and Complex Diseases,,Microbial Pathogenesis and Immunology, School of Medicine, Texas A&M University Health Science Center, College Station, TX
| | - Robert S. Chapkin
- Program in Integrative Nutrition and Complex Diseases,,Nutrition and Food Science,,Center for Translational Environmental Health Research, Texas A&M University, College Station, TX; and,Microbial Pathogenesis and Immunology, School of Medicine, Texas A&M University Health Science Center, College Station, TX,To whom correspondence should be addressed. E-mail:
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12
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Monk JM, Hou TY, Turk HF, McMurray DN, Chapkin RS. n3 PUFAs reduce mouse CD4+ T-cell ex vivo polarization into Th17 cells. J Nutr 2013; 143:1501-8. [PMID: 23864512 PMCID: PMC3743278 DOI: 10.3945/jn.113.178178] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Revised: 05/03/2013] [Accepted: 06/19/2013] [Indexed: 12/18/2022] Open
Abstract
Little is known about the impact of n3 (ω3) PUFAs on polarization of CD4(+) T cells into effector subsets other than Th1 and Th2. We assessed the effects of dietary fat [corn oil (CO) vs. fish oil (FO)] and fermentable fiber [cellulose (C) vs. pectin (P)] (2 × 2 design) in male C57BL/6 mice fed CO-C, CO-P, FO-C, or FO-P diets for 3 wk on the ex vivo polarization of purified splenic CD4(+) T cells (using magnetic microbeads) into regulatory T cells [Tregs; forkhead box P3 (Foxp3(+)) cells] or Th17 cells [interleukin (IL)-17A(+) and retinoic acid receptor-related orphan receptor (ROR) γτ(+) cells] by flow cytometry. Treg polarization was unaffected by diet; however, FO independently reduced the percentage of both CD4(+) IL-17A(+) (P < 0.05) and CD4(+) RORγτ(+) cells (P < 0.05). Moreover, expression of another critical Th17-cell-related transcription factor, signal transducer and activator of transcription 3, was reduced by FO. Dietary FO reduced the surface expression of both IL-6R and IL-23R on polarized Th17 cells (P ≤ 0.05), thus interfering with the promotive effects of these critical cytokines on Th17 polarization. Additionally, C57BL/6 mice fed diets enriched in eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), or DHA + EPA similarly reduced Th17-cell polarization in comparison to CO by reducing expression of the Th17-cell signature cytokine (IL-17A; P = 0.0015) and transcription factor (RORγτ P = 0.02), whereas Treg polarization was unaffected. Collectively, these data show that n3 PUFAs exert a direct effect on the development of Th17 cells in healthy mice, implicating a novel n3 PUFA-dependent, anti-inflammatory mechanism of action via the suppression of the initial development of this inflammatory T-cell subset.
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Affiliation(s)
- Jennifer M. Monk
- Program in Integrative Nutrition and Complex Diseases
- Department of Nutrition and Food Science, and
| | - Tim Y. Hou
- Program in Integrative Nutrition and Complex Diseases
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX; and
| | - Harmony F. Turk
- Program in Integrative Nutrition and Complex Diseases
- Department of Nutrition and Food Science, and
| | - David N. McMurray
- Department of Nutrition and Food Science, and
- Department of Microbial and Molecular Pathogenesis, Texas A&M University System Health Science Center, College Station, TX
| | - Robert S. Chapkin
- Program in Integrative Nutrition and Complex Diseases
- Department of Nutrition and Food Science, and
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX; and
- Department of Microbial and Molecular Pathogenesis, Texas A&M University System Health Science Center, College Station, TX
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13
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Fan YY, Monk JM, Hou TY, Callway E, Vincent L, Weeks B, Yang P, Chapkin RS. Characterization of an arachidonic acid-deficient (Fads1 knockout) mouse model. J Lipid Res 2012; 53:1287-95. [PMID: 22534642 DOI: 10.1194/jlr.m024216] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Arachidonic acid (20:4(Δ5,8,11,14), AA)-derived eicosanoids regulate inflammation and promote cancer development. Previous studies have targeted prostaglandin enzymes in an attempt to modulate AA metabolism. However, due to safety concerns surrounding the use of pharmaceutical agents designed to target Ptgs2 (cyclooxygenase 2) and its downstream targets, it is important to identify new targets upstream of Ptgs2. Therefore, we determined the utility of antagonizing tissue AA levels as a novel approach to suppressing AA-derived eicosanoids. Systemic disruption of the Fads1 (Δ5 desaturase) gene reciprocally altered the levels of dihomo-γ-linolenic acid (20:3(Δ8,11,14), DGLA) and AA in mouse tissues, resulting in a profound increase in 1-series-derived and a concurrent decrease in 2-series-derived prostaglandins. The lack of AA-derived eicosanoids, e.g., PGE₂ was associated with perturbed intestinal crypt proliferation, immune cell homeostasis, and a heightened sensitivity to acute inflammatory challenge. In addition, null mice failed to thrive, dying off by 12 weeks of age. Dietary supplementation with AA extended the longevity of null mice to levels comparable to wild-type mice. We propose that this new mouse model will expand our understanding of how AA and its metabolites mediate inflammation and promote malignant transformation, with the eventual goal of identifying new drug targets upstream of Ptgs2.
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Affiliation(s)
- Yang-Yi Fan
- Program in Integrative Nutrition and Complex Diseases, Texas A&M University, College Station, TX 77843, USA
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14
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Abstract
Every 4 years, researchers in the cross-disciplinary field of nutritional immunology convene for a FASEB-sponsored meeting entitled, "Nutritional Immunology: Role in Health and Disease", which was held this summer in Carefree, AZ, USA. The scope of the conference encompassed a diverse list of research topics, including, but not restricted to, obesity and immune dysfunction, nutrient-gene interactions, mucosal immunity and a discussion of future directions for the field. Here, we summarize some of the findings shared at the conference, specifically focusing on obesity, immunological function of dietary components (n-3 polyunsaturated fatty acids and flavanoids), gut immunity and the microbiota, and relevant emerging technologies and databases.
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Affiliation(s)
- Jennifer M Monk
- Program in Integrative Nutrition & Complex Diseases, Texas A&M University, College Station, TX, USA
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15
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Ward SM, Fernando SJ, Hou TY, Duffield GE. The transcriptional repressor ID2 can interact with the canonical clock components CLOCK and BMAL1 and mediate inhibitory effects on mPer1 expression. J Biol Chem 2010; 285:38987-9000. [PMID: 20861012 PMCID: PMC2998095 DOI: 10.1074/jbc.m110.175182] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2010] [Revised: 09/21/2010] [Indexed: 01/15/2023] Open
Abstract
ID2 is a rhythmically expressed HLH transcriptional repressor. Deletion of Id2 in mice results in circadian phenotypes, highlighted by disrupted locomotor activity rhythms and an enhanced photoentrainment response. ID2 can suppress the transactivation potential of the positive elements of the clock, CLOCK-BMAL1, on mPer1 and clock-controlled gene (CCG) activity. Misregulation of CCGs is observed in Id2(-/-) liver, and mutant mice exhibit associated alterations in lipid homeostasis. These data suggest that ID2 contributes to both input and output components of the clock and that this may be via interaction with the bHLH clock proteins CLOCK and BMAL1. The aim of the present study was to explore this potential interaction. Coimmunoprecipitation analysis revealed the capability of ID2 to complex with both CLOCK and BMAL1, and mammalian two-hybrid analysis revealed direct interactions of ID2, ID1 and ID3 with CLOCK and BMAL1. Deletion of the ID2 HLH domain rendered ID2 ineffective at inhibiting CLOCK-BMAL1 transactivation, suggesting that interaction between the proteins is via the HLH region. Immunofluorescence analysis revealed overlapping localization of ID2 with CLOCK and BMAL1 in the cytoplasm. Overexpression of CLOCK and BMAL1 in the presence of ID2 resulted in a significant reduction in their nuclear localization, revealing that ID2 can sequester CLOCK and BMAL1 to the cytoplasm. Serum stimulation of Id2(-/-) mouse embryonic fibroblasts resulted in an enhanced induction of mPer1 expression. These data provide the basis for a molecular mechanism through which ID2 could regulate aspects of both clock input and output through a time-of-day specific interaction with CLOCK and BMAL1.
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Affiliation(s)
- Sarah M. Ward
- From the Department of Biological Sciences, Galvin Life Science Center, University of Notre Dame, Notre Dame, Indiana 46556
| | - Shanik J. Fernando
- From the Department of Biological Sciences, Galvin Life Science Center, University of Notre Dame, Notre Dame, Indiana 46556
| | - Tim Y. Hou
- From the Department of Biological Sciences, Galvin Life Science Center, University of Notre Dame, Notre Dame, Indiana 46556
| | - Giles E. Duffield
- From the Department of Biological Sciences, Galvin Life Science Center, University of Notre Dame, Notre Dame, Indiana 46556
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16
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Lu C, Xu H, Ranjith-Kumar CT, Brooks MT, Hou TY, Hu F, Herr AB, Strong RK, Kao CC, Li P. The structural basis of 5' triphosphate double-stranded RNA recognition by RIG-I C-terminal domain. Structure 2010; 18:1032-43. [PMID: 20637642 PMCID: PMC2919622 DOI: 10.1016/j.str.2010.05.007] [Citation(s) in RCA: 174] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2010] [Revised: 05/13/2010] [Accepted: 05/15/2010] [Indexed: 12/25/2022]
Abstract
RIG-I is a cytosolic sensor of viral RNA that plays crucial roles in the induction of type I interferons. The C-terminal domain (CTD) of RIG-I is responsible for the recognition of viral RNA with 5' triphosphate (ppp). However, the mechanism of viral RNA recognition by RIG-I is still not fully understood. Here, we show that RIG-I CTD binds 5' ppp dsRNA or ssRNA, as well as blunt-ended dsRNA, and exhibits the highest affinity for 5' ppp dsRNA. Crystal structures of RIG-I CTD bound to 5' ppp dsRNA with GC- and AU-rich sequences revealed that RIG-I recognizes the termini of the dsRNA and interacts with the 5' ppp through extensive electrostatic interactions. Mutagenesis and RNA-binding studies demonstrated that similar binding surfaces are involved in the recognition of different forms of RNA. Mutations of key residues at the RNA-binding surface affected RIG-I signaling in cells.
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Affiliation(s)
- Cheng Lu
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843-2128, USA
| | - Hengyu Xu
- Divison of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - C. T. Ranjith-Kumar
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington IN 47405, USA
| | - Monica T. Brooks
- Department of Molecular Genetics, Biochemistry, and Microbiology, University of Cincinnati College of Medicine, Cincinnati, OH 45267-0524, USA
| | - Tim Y. Hou
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843-2128, USA
| | - Fuqu Hu
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843-2128, USA
| | - Andrew B. Herr
- Department of Molecular Genetics, Biochemistry, and Microbiology, University of Cincinnati College of Medicine, Cincinnati, OH 45267-0524, USA
| | - Roland K. Strong
- Divison of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - C. Cheng Kao
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington IN 47405, USA
| | - Pingwei Li
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843-2128, USA
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17
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Hou TY, Ward SM, Murad JM, Watson NP, Israel MA, Duffield GE. ID2 (inhibitor of DNA binding 2) is a rhythmically expressed transcriptional repressor required for circadian clock output in mouse liver. J Biol Chem 2009; 284:31735-45. [PMID: 19740747 DOI: 10.1074/jbc.m109.013961] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Id2 is a helix-loop-helix transcription factor gene expressed in a circadian manner in multiple tissues with a phase-locked relationship with canonical clock genes. Our previous studies have identified circadian phenotypes in Id2 null mice, including enhanced photo-entrainment and disruption of activity rhythms, and have demonstrated a potent inhibitory effect of ID proteins upon CLOCK-BMAL1 transactivation of clock gene and clock-controlled gene activity. We have now begun to explore the potential role that ID2 may play in specifically regulating clock output. Here we show that ID2 protein is rhythmically expressed in mouse liver. Time-of-day-specific liver gene expression in Id2(+/+) and Id2(-/-) mice under circadian conditions was studied using DNA microarray analysis, identifying 651 differentially expressed genes, including a subset of 318 genes deemed rhythmically expressed in other studies. Examination of individual time courses reveals that these genes are dysregulated in a highly time-specific manner. A cohort of different functional groups were identified, including genes associated with glucose and lipid metabolism, e.g. serum protein Igfbp1 and lipoprotein lipase. We also reveal that the Id2(-/-) mice show a reduction in lipid storage in the liver and white adipose tissue, suggesting that disruption of normal circadian activity of components of lipid metabolism can result in overt physiological alterations. These data reveal a role for the transcriptional repressor ID2 as a circadian output regulator in the periphery.
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Affiliation(s)
- Tim Y Hou
- Department of Biological Sciences, Galvin Life Science Center, University of Notre Dame, Notre Dame, Indiana 46556, USA
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18
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Hou TY, Chang DM, Gao HW, Chen CH, Chen HC, Lai JH. Sweet's syndrome as an initial presentation in systemic lupus erythematosus: a case report and review of the literature. Lupus 2005; 14:399-402. [PMID: 15934441 DOI: 10.1191/0961203305lu2083cr] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Malar or discoid rash is the most frequent specific cutaneous lesion for systemic lupus erythematosus (SLE). Neutrophilic dermatosis as an initial presentation in SLE is unusual. We describe a 38-year old female patient who primarily suffered from erythematous tender plaques and fever. Examination of skin biopsy of the plaques showed dense neutrophilic infiltration in the dermis. Polyarthritis, heavy proteinuria, photosensitivity and positive antinuclear antibodies (ANA > 1:1280) concluded the diagnosis of SLE. The plaques disappeared completely after treatment with systemic corticosteroids. To our knowledge, this is the first reported SLE patient with Sweet's syndrome as the initial presentation in literature review.
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Affiliation(s)
- T Y Hou
- Division of Rheumatology/Immunology/Allergy, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, Republic of China
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Huang DJ, Wu WB, Guo GY, Lin HJ, Hou TY, Chang CF, Chen CT, Fujimori A, Kimura T, Huang HB, Tanaka A, Jo T. Orbital ordering in La0.5Sr1.5MnO4 studied by soft X-ray linear dichroism. Phys Rev Lett 2004; 92:087202. [PMID: 14995808 DOI: 10.1103/physrevlett.92.087202] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2003] [Revised: 11/17/2003] [Indexed: 05/24/2023]
Abstract
We found that the conventional model of orbital-ordering of 3x(2)-r(2)/3y(2)-r(2) type in the e(g) states of La0.5Sr1.5MnO4 is incompatible with measurements of linear dichroism in the Mn 2p-edge x-ray absorption, whereas these e(g) states exhibit predominantly cross-type orbital ordering of x(2)-z(2)/y(2)-z(2). LDA+U band-structure calculations reveal that such a cross-type orbital-ordering results from a combined effect of antiferromagnetic structure, Jahn-Teller distortion, and on-site Coulomb interactions.
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Affiliation(s)
- D J Huang
- National Synchrotron Radiation Research Center, Hsinchu 30077, Taiwan
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20
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Hou TY, Dai MS, Kao WY. Testicular plasmacytoma with bone dissemination without medullary plasmacytosis. Ann Hematol 2003; 82:518-520. [PMID: 12838369 DOI: 10.1007/s00277-003-0672-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2003] [Accepted: 04/13/2003] [Indexed: 10/26/2022]
Abstract
A 34-year-old man was diagnosed as having solitary testicular plasmacytoma. He had received palliative radiotherapy, several combined chemotherapies including CHOP chemotherapy (vincristine, cyclophosphamide, Adriamycin, and prednisone), MP (melphalan and prednisone) and M-2 protocol (melphalan, prednisone, vincristine, carmustine, and cyclophosphamide), and interferon therapy as 3 million units subcutaneous injection three times a week for 1 year. Extensive bone plasmacytoma developed 7 years later without bone marrow involvement. We suggest that early use of combined chemoradiotherapy and high-dose chemotherapy with autologous stem cell support should be investigated in patients with testicular plasmacytoma with dissemination.
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Affiliation(s)
- T Y Hou
- Division of Hematology/Oncology, Department of Medicine, Tri-Service General Hospital, National Defense Medical Center, No. 325, Section 2, Cheng-Kung Road, Neihu 114, Taipei, Taiwan
| | - M S Dai
- Division of Hematology/Oncology, Department of Medicine, Tri-Service General Hospital, National Defense Medical Center, No. 325, Section 2, Cheng-Kung Road, Neihu 114, Taipei, Taiwan.
| | - W Y Kao
- Division of Hematology/Oncology, Department of Medicine, Tri-Service General Hospital, National Defense Medical Center, No. 325, Section 2, Cheng-Kung Road, Neihu 114, Taipei, Taiwan
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Chow BF, Blackwell RQ, Blackwell BN, Hou TY, Anilane JK, Sherwin RW. Maternal nutrition and metabolism of the offspring: studies in rats and man. Am J Public Health Nations Health 1968; 58:668-77. [PMID: 5689316 PMCID: PMC1228378 DOI: 10.2105/ajph.58.4.668] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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