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Bagheri-Yarmand R, Sinha KM, Gururaj AE, Ahmed Z, Rizvi YQ, Huang SC, Ladbury JE, Bogler O, Williams MD, Cote GJ, Gagel RF. A novel dual kinase function of the RET proto-oncogene negatively regulates activating transcription factor 4-mediated apoptosis. J Biol Chem 2015; 290:11749-61. [PMID: 25795775 DOI: 10.1074/jbc.m114.619833] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Indexed: 11/06/2022] Open
Abstract
The RET proto-oncogene, a tyrosine kinase receptor, is widely known for its essential role in cell survival. Germ line missense mutations, which give rise to constitutively active oncogenic RET, were found to cause multiple endocrine neoplasia type 2, a dominant inherited cancer syndrome that affects neuroendocrine organs. However, the mechanisms by which RET promotes cell survival and prevents cell death remain elusive. We demonstrate that in addition to cytoplasmic localization, RET is localized in the nucleus and functions as a tyrosine-threonine dual specificity kinase. Knockdown of RET by shRNA in medullary thyroid cancer-derived cells stimulated expression of activating transcription factor 4 (ATF4), a master transcription factor for stress-induced apoptosis, through activation of its target proapoptotic genes NOXA and PUMA. RET knockdown also increased sensitivity to cisplatin-induced apoptosis. We observed that RET physically interacted with and phosphorylated ATF4 at tyrosine and threonine residues. Indeed, RET kinase activity was required to inhibit the ATF4-dependent activation of the NOXA gene because the site-specific substitution mutations that block threonine phosphorylation increased ATF4 stability and activated its targets NOXA and PUMA. Moreover, chromatin immunoprecipitation assays revealed that ATF4 occupancy increased at the NOXA promoter in TT cells treated with tyrosine kinase inhibitors or the ATF4 inducer eeyarestatin as well as in RET-depleted TT cells. Together these findings reveal RET as a novel dual kinase with nuclear localization and provide mechanisms by which RET represses the proapoptotic genes through direct interaction with and phosphorylation-dependent inactivation of ATF4 during the pathogenesis of medullary thyroid cancer.
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Affiliation(s)
| | - Krishna M Sinha
- From the Department of Endocrine Neoplasia and Hormonal Disorders
| | | | - Zamal Ahmed
- the Department of Biochemistry and Molecular Biology and Center for Biomolecular Structure and Function, and
| | - Yasmeen Q Rizvi
- From the Department of Endocrine Neoplasia and Hormonal Disorders
| | - Su-Chen Huang
- From the Department of Endocrine Neoplasia and Hormonal Disorders
| | - John E Ladbury
- the Department of Biochemistry and Molecular Biology and Center for Biomolecular Structure and Function, and
| | | | - Michelle D Williams
- the Department of Pathology, University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030
| | - Gilbert J Cote
- From the Department of Endocrine Neoplasia and Hormonal Disorders
| | - Robert F Gagel
- From the Department of Endocrine Neoplasia and Hormonal Disorders
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2
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Hara T, Mizuguchi M, Fujii M, Nakamura M. Krüppel-like factor 2 represses transcription of the telomerase catalytic subunit human telomerase reverse transcriptase (hTERT) in human T cells. J Biol Chem 2015; 290:8758-63. [PMID: 25694435 DOI: 10.1074/jbc.m114.610386] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2014] [Indexed: 11/06/2022] Open
Abstract
In normal human T cells, telomerase activity is strictly regulated. T cells are thought to express telomerase to avoid replicative senescence, unlike most normal somatic cells with definite replicative lifespan. T cells in blood and tissues are usually in a state of quiescence without expression of the limiting catalytic subunit of telomerase, human telomerase reverse transcriptase (hTERT). In contrast to activation, repression of hTERT transcription has not been studied well. Our previous studies have found an hTERT promoter element with repressive function. Here we identified KLF2, which represses hTERT transcription by binding to the putative promoter element. KLF2 and hTERT exhibited reciprocal mRNA expression patterns in primary human T cells. In activated T cells, KLF2 binding to the hTERT promoter was eliminated, relieving the repression of hTERT transcription found in resting T cells. Our results suggest that KLF2 is involved in strict repression of hTERT expression through binding to the promoter in primary human T cells.
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Affiliation(s)
- Toshifumi Hara
- From the Human Gene Sciences Center, Tokyo Medical and Dental University, Tokyo 113-8510 and the Division of Virology, Niigata University Graduate School of Medicine and Dental Sciences, Niigata 951-8510, Japan
| | - Mariko Mizuguchi
- From the Human Gene Sciences Center, Tokyo Medical and Dental University, Tokyo 113-8510 and
| | - Masahiro Fujii
- the Division of Virology, Niigata University Graduate School of Medicine and Dental Sciences, Niigata 951-8510, Japan
| | - Masataka Nakamura
- From the Human Gene Sciences Center, Tokyo Medical and Dental University, Tokyo 113-8510 and
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3
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Schöler J, Ferralli J, Thiry S, Chiquet-Ehrismann R. The intracellular domain of teneurin-1 induces the activity of microphthalmia-associated transcription factor (MITF) by binding to transcriptional repressor HINT1. J Biol Chem 2015; 290:8154-65. [PMID: 25648896 DOI: 10.1074/jbc.m114.615922] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [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: 02/03/2023] Open
Abstract
Teneurins are large type II transmembrane proteins that are necessary for the normal development of the CNS. Although many studies highlight the significance of teneurins, especially during development, there is only limited information known about the molecular mechanisms of function. Previous studies have shown that the N-terminal intracellular domain (ICD) of teneurins can be cleaved at the membrane and subsequently translocates to the nucleus, where it can influence gene transcription. Because teneurin ICDs do not contain any intrinsic DNA binding sequences, interaction partners are required to affect transcription. Here, we identified histidine triad nucleotide binding protein 1 (HINT1) as a human teneurin-1 ICD interaction partner in a yeast two-hybrid screen. This interaction was confirmed in human cells, where HINT1 is known to inhibit the transcription of target genes by directly binding to transcription factors at the promoter. In a whole transcriptome analysis of BS149 glioblastoma cells overexpressing the teneurin-1 ICD, several microphthalmia-associated transcription factor (MITF) target genes were found to be up-regulated. Directly comparing the transcriptomes of MITF versus TEN1-ICD-overexpressing BS149 cells revealed 42 co-regulated genes, including glycoprotein non-metastatic b (GPNMB). Using real-time quantitative PCR to detect endogenous GPNMB expression upon overexpression of MITF and HINT1 as well as promoter reporter assays using GPNMB promoter constructs, we could demonstrate that the teneurin-1 ICD binds HINT1, thus switching on MITF-dependent transcription of GPNMB.
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Affiliation(s)
- Jonas Schöler
- From the Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland and the Faculty of Science, University of Basel, Klingelbergstrasse 50, 4056 Basel, Switzerland
| | - Jacqueline Ferralli
- From the Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland and
| | - Stéphane Thiry
- From the Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland and
| | - Ruth Chiquet-Ehrismann
- From the Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland and the Faculty of Science, University of Basel, Klingelbergstrasse 50, 4056 Basel, Switzerland
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4
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Hortschansky P, Ando E, Tuppatsch K, Arikawa H, Kobayashi T, Kato M, Haas H, Brakhage AA. Deciphering the combinatorial DNA-binding code of the CCAAT-binding complex and the iron-regulatory basic region leucine zipper (bZIP) transcription factor HapX. J Biol Chem 2015; 290:6058-70. [PMID: 25589790 DOI: 10.1074/jbc.m114.628677] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The heterotrimeric CCAAT-binding complex (CBC) is evolutionarily conserved in eukaryotic organisms, including fungi, plants, and mammals. The CBC consists of three subunits, which are named in the filamentous fungus Aspergillus nidulans HapB, HapC, and HapE. HapX, a fourth CBC subunit, was identified exclusively in fungi, except for Saccharomyces cerevisiae and the closely related Saccharomycotina species. The CBC-HapX complex acts as the master regulator of iron homeostasis. HapX belongs to the class of basic region leucine zipper transcription factors. We demonstrated that the CBC and HapX bind cooperatively to bipartite DNA motifs with a general HapX/CBC/DNA 2:1:1 stoichiometry in a class of genes that are repressed by HapX-CBC in A. nidulans during iron limitation. This combinatorial binding mode requires protein-protein interaction between the N-terminal domain of HapE and the N-terminal CBC binding domain of HapX as well as sequence-specific DNA binding of both the CBC and HapX. Initial binding of the CBC to CCAAT boxes is mandatory for DNA recognition of HapX. HapX specifically targets the minimal motif 5'-GAT-3', which is located at a distance of 11-12 bp downstream of the respective CCAAT box. Single nucleotide substitutions at the 5'- and 3'-end of the GAT motif as well as different spacing between the CBC and HapX DNA-binding sites revealed a remarkable promiscuous DNA-recognition mode of HapX. This flexible DNA-binding code may have evolved as a mechanism for fine-tuning the transcriptional activity of CBC-HapX at distinct target promoters.
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Affiliation(s)
- Peter Hortschansky
- From the Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology, D-07745 Jena, Germany
| | - Eriko Ando
- the Department of Biological Mechanisms and Functions, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan
| | - Katja Tuppatsch
- From the Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology, D-07745 Jena, Germany
| | - Hisashi Arikawa
- the Department of Biological Mechanisms and Functions, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan
| | - Tetsuo Kobayashi
- the Department of Biological Mechanisms and Functions, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan
| | - Masashi Kato
- the Faculty of Agriculture, Meijo University, Shiogama-guchi 1-501, Nagoya 468-8502, Japan
| | - Hubertus Haas
- the Division of Molecular Biology, Biocenter, Innsbruck Medical University, A-6020 Innsbruck, Austria, and
| | - Axel A Brakhage
- From the Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology, D-07745 Jena, Germany, the Department of Microbiology and Molecular Biology, Institute for Microbiology, Friedrich Schiller University, D-07743 Jena, Germany
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5
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Crowe AM, Stogios PJ, Casabon I, Evdokimova E, Savchenko A, Eltis LD. Structural and functional characterization of a ketosteroid transcriptional regulator of Mycobacterium tuberculosis. J Biol Chem 2014; 290:872-82. [PMID: 25406313 DOI: 10.1074/jbc.m114.607481] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Catabolism of host cholesterol is critical to the virulence of Mycobacterium tuberculosis and is a potential target for novel therapeutics. KstR2, a TetR family repressor (TFR), regulates the expression of 15 genes encoding enzymes that catabolize the last half of the cholesterol molecule, represented by 3aα-H-4α(3'-propanoate)-7aβ-methylhexahydro-1,5-indane-dione (HIP). Binding of KstR2 to its operator sequences is relieved upon binding of HIP-CoA. A 1.6-Å resolution crystal structure of the KstR2(Mtb)·HIP-CoA complex reveals that the KstR2(Mtb) dimer accommodates two molecules of HIP-CoA. Each ligand binds in an elongated cleft spanning the dimerization interface such that the HIP and CoA moieties interact with different KstR2(Mtb) protomers. In isothermal titration calorimetry studies, the dimer bound 2 eq of HIP-CoA with high affinity (K(d) = 80 ± 10 nm) but bound neither HIP nor CoASH. Substitution of Arg-162 or Trp-166, residues that interact, respectively, with the diphosphate and HIP moieties of HIP-CoA, dramatically decreased the affinity of KstR2(Mtb) for HIP-CoA but not for its operator sequence. The variant of R162M that decreased the affinity for HIP-CoA (ΔΔG = 13 kJ mol(-1)) is consistent with the loss of three hydrogen bonds as indicated in the structural data. A 24-bp operator sequence bound two dimers of KstR2. Structural comparisons with a ligand-free rhodococcal homologue and a DNA-bound homologue suggest that HIP-CoA induces conformational changes of the DNA-binding domains of the dimer that preclude their proper positioning in the major groove of DNA. The results provide insight into KstR2-mediated regulation of expression of steroid catabolic genes and the determinants of ligand binding in TFRs.
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Affiliation(s)
- Adam M Crowe
- From the Departments of Biochemistry and Molecular Biology and
| | - Peter J Stogios
- the Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto M5S 3E5, Canada, and
| | - Israël Casabon
- Microbiology and Immunology, Life Sciences Institute, The University of British Columbia, Vancouver V6T 1Z3, Canada
| | - Elena Evdokimova
- the Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto M5S 3E5, Canada, and The Midwest Center for Structural Genomics (MCSG), Argonne National Laboratory, Argonne, Illinois 60439
| | - Alexei Savchenko
- the Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto M5S 3E5, Canada, and The Midwest Center for Structural Genomics (MCSG), Argonne National Laboratory, Argonne, Illinois 60439
| | - Lindsay D Eltis
- From the Departments of Biochemistry and Molecular Biology and Microbiology and Immunology, Life Sciences Institute, The University of British Columbia, Vancouver V6T 1Z3, Canada,
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6
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Abstract
The 5 S rRNA gene-specific transcription factor IIIA (TFIIIA) interacts with the small ubiquitin-like modifier (SUMO) E3 ligase PIAS2b and with one of its targets, the transcriptional corepressor, XCtBP. PIAS2b is restricted to the cytoplasm of Xenopus oocytes but relocates to the nucleus immediately after fertilization. Following the midblastula transition, PIAS2b and XCtBP are present on oocyte-type, but not somatic-type, 5 S rRNA genes up through the neurula stage, as is a limiting amount of TFIIIA. Histone H3 methylation, coincident with the binding of XCtBP, also occurs exclusively on the oocyte-type genes. Immunohistochemical staining of embryos confirms the occupancy of a subset of the oocyte-type genes by TFIIIA that become positioned at the nuclear periphery shortly after the midblastula transition. Inhibition of SUMOylation activity relieves repression of oocyte-type 5 S rRNA genes and is correlated with a decrease in methylation of H3K9 and H3K27 and disruption of subnuclear localization. These results reveal a novel function for TFIIIA as a negative regulator that recruits histone modification activity through the CtBP repressor complex exclusively to the oocyte-type 5 S rRNA genes, leading to their terminal repression.
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Affiliation(s)
- Mariam Q Malik
- From the Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556
| | - Michelle M Bertke
- From the Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556
| | - Paul W Huber
- From the Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556
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7
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Yoon J, Feng X, Kim YS, Shin DM, Hatzi K, Wang H, Morse HC. Interferon regulatory factor 8 (IRF8) interacts with the B cell lymphoma 6 (BCL6) corepressor BCOR. J Biol Chem 2014; 289:34250-7. [PMID: 25331958 DOI: 10.1074/jbc.m114.571182] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [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: 02/05/2023] Open
Abstract
B cell lymphoma 6 (BCL6) corepressor (BCOR) was discovered as a BCL6-interacting corepressor, but little is known about its other biological activities in normal B cell development and function. Previously, we found that interferon regulatory factor 8 (IRF8), also known as interferon consensus sequence-binding protein, directly targets a large number of genes in germinal center B cells including BCL6. In this study, we screened potential binding partners of IRF8 using a retrovirus-based protein complementation assay screen in a mouse pre-B cell line. We found that IRF8 interacts directly with BCOR and that the α-helical region of IRF8 and the BCL6 binding domain of BCOR are required for this interaction. In addition, IRF8 protein interacts directly with BCL6. Using an siRNA-mediated IRF8 knockdown mouse B cell lymphoma cell line, we showed that IRF8 represses Bcor and enhances Bcl6 transcription. Taken together, these data suggest that a complex comprising BCOR-BCL6-IRF8 modulates BCL6-associated transcriptional regulation of germinal center B cell function.
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Affiliation(s)
- Jeongheon Yoon
- From the Laboratory of Immunogenetics, NIAID, National Institutes of Health, Rockville, Maryland 20852 and
| | - Xianxum Feng
- From the Laboratory of Immunogenetics, NIAID, National Institutes of Health, Rockville, Maryland 20852 and
| | - Yong-Soo Kim
- From the Laboratory of Immunogenetics, NIAID, National Institutes of Health, Rockville, Maryland 20852 and
| | - Dong-Mi Shin
- From the Laboratory of Immunogenetics, NIAID, National Institutes of Health, Rockville, Maryland 20852 and
| | - Katerina Hatzi
- Division of Hematology and Medical Oncology, Department of Medicine and Department of Pharmacology, Weill Cornell Medical College, New York, New York 10065
| | - Hongsheng Wang
- From the Laboratory of Immunogenetics, NIAID, National Institutes of Health, Rockville, Maryland 20852 and
| | - Herbert C Morse
- From the Laboratory of Immunogenetics, NIAID, National Institutes of Health, Rockville, Maryland 20852 and
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8
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Ying M, Tilghman J, Wei Y, Guerrero-Cazares H, Quinones-Hinojosa A, Ji H, Laterra J. Kruppel-like factor-9 (KLF9) inhibits glioblastoma stemness through global transcription repression and integrin α6 inhibition. J Biol Chem 2014; 289:32742-56. [PMID: 25288800 DOI: 10.1074/jbc.m114.588988] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [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: 12/21/2022] Open
Abstract
It is increasingly important to understand the molecular basis for the plasticity of neoplastic cells and their capacity to transition between differentiated and stemlike phenotypes. Kruppel-like factor-9 (KLF9), a member of the large KLF transcription factor family, has emerged as a regulator of oncogenesis, cell differentiation, and neural development; however, the molecular basis for the diverse contextual functions of KLF9 remains unclear. This study focused on the functions of KLF9 in human glioblastoma stemlike cells. We established for the first time a genome-wide map of KLF9-regulated targets in human glioblastoma stemlike cells and show that KLF9 functions as a transcriptional repressor and thereby regulates multiple signaling pathways involved in oncogenesis and stem cell regulation. A detailed analysis of one such pathway, integrin signaling, showed that the capacity of KLF9 to inhibit glioblastoma cell stemness and tumorigenicity requires ITGA6 repression. These findings enhance our understanding of the transcriptional networks underlying cancer cell stemness and differentiation and identify KLF9-regulated molecular targets applicable to cancer therapeutics.
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Affiliation(s)
- Mingyao Ying
- From the Hugo W. Moser Research Institute at Kennedy Krieger, Baltimore, Maryland 21205, Departments of Neurology
| | - Jessica Tilghman
- From the Hugo W. Moser Research Institute at Kennedy Krieger, Baltimore, Maryland 21205, Neuroscience
| | - Yingying Wei
- Department of Statistics, Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | | | - Alfredo Quinones-Hinojosa
- Neuroscience, Neurosurgery, The Johns Hopkins School of Medicine, Baltimore, Maryland 21205, Oncology, and
| | - Hongkai Ji
- Department of Biostatistics, The Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, 21205, and
| | - John Laterra
- From the Hugo W. Moser Research Institute at Kennedy Krieger, Baltimore, Maryland 21205, Departments of Neurology, Neuroscience, Oncology, and
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9
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Chakraborty S, Das K, Saha S, Mazumdar M, Manna A, Chakraborty S, Mukherjee S, Khan P, Adhikary A, Mohanty S, Chattopadhyay S, Biswas SC, Sa G, Das T. Nuclear matrix protein SMAR1 represses c-Fos-mediated HPV18 E6 transcription through alteration of chromatin histone deacetylation. J Biol Chem 2014; 289:29074-85. [PMID: 25157104 DOI: 10.1074/jbc.m114.564872] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [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] Open
Abstract
Matrix attachment region (MAR)-binding proteins have been implicated in the transcriptional regulation of host as well as viral genes, but their precise role in HPV-infected cervical cancer remains unclear. Here we show that HPV18 promoter contains consensus MAR element in the LCR and E6 sequences where SMAR1 binds and reinforces HPV18 E6 transcriptional silencing. In fact, curcumin-induced up-regulation of SMAR1 ensures recruitment of SMAR1-HDAC1 repressor complex at the LCR and E6 MAR sequences, thereby decreasing histone acetylation at H3K9 and H3K18, leading to reorientation of the chromatin. As a consequence, c-Fos binding at the putative AP-1 sites on E6 promoter is inhibited. E6 depletion interrupts degradation of E6-mediated p53 and lysine acetyl transferase, Tip60. Tip60, in turn, acetylates p53, thereby restoring p53-mediated transactivation of proapoptotic genes to ensure apoptosis. This hitherto unexplained function of SMAR1 signifies the potential of this unique scaffold matrix-associated region-binding protein as a critical regulator of E6-mediated anti-apoptotic network in HPV18-infected cervical adenocarcinoma. These results also justify the candidature of curcumin for the treatment of HPV18-infected cervical carcinoma.
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Affiliation(s)
- Samik Chakraborty
- From the Division of Molecular Medicine, Bose Institute, P1/12, Calcutta Improvement Trust Scheme VIIM, Kolkata 700054, West Bengal, India
| | - Kaushik Das
- From the Division of Molecular Medicine, Bose Institute, P1/12, Calcutta Improvement Trust Scheme VIIM, Kolkata 700054, West Bengal, India
| | - Shilpi Saha
- From the Division of Molecular Medicine, Bose Institute, P1/12, Calcutta Improvement Trust Scheme VIIM, Kolkata 700054, West Bengal, India
| | - Minakshi Mazumdar
- From the Division of Molecular Medicine, Bose Institute, P1/12, Calcutta Improvement Trust Scheme VIIM, Kolkata 700054, West Bengal, India
| | - Argha Manna
- From the Division of Molecular Medicine, Bose Institute, P1/12, Calcutta Improvement Trust Scheme VIIM, Kolkata 700054, West Bengal, India
| | - Sreeparna Chakraborty
- From the Division of Molecular Medicine, Bose Institute, P1/12, Calcutta Improvement Trust Scheme VIIM, Kolkata 700054, West Bengal, India
| | - Shravanti Mukherjee
- From the Division of Molecular Medicine, Bose Institute, P1/12, Calcutta Improvement Trust Scheme VIIM, Kolkata 700054, West Bengal, India
| | - Poulami Khan
- From the Division of Molecular Medicine, Bose Institute, P1/12, Calcutta Improvement Trust Scheme VIIM, Kolkata 700054, West Bengal, India
| | - Arghya Adhikary
- From the Division of Molecular Medicine, Bose Institute, P1/12, Calcutta Improvement Trust Scheme VIIM, Kolkata 700054, West Bengal, India
| | - Suchismita Mohanty
- From the Division of Molecular Medicine, Bose Institute, P1/12, Calcutta Improvement Trust Scheme VIIM, Kolkata 700054, West Bengal, India
| | - Samit Chattopadhyay
- the National Centre for Cell Science, Pune University Campus, Ganeshkhind, Pune 411007, Maharashtra, India, and
| | - Subhash C Biswas
- the Department of Gynecology & Obstetrics, Institute of Post-Graduate Medical Education and Research (IPGMER), Seth Sukhlal Karnani Memorial (SSKM) Hospital, Kolkata 700020, West Bengal, India
| | - Gaurisankar Sa
- From the Division of Molecular Medicine, Bose Institute, P1/12, Calcutta Improvement Trust Scheme VIIM, Kolkata 700054, West Bengal, India
| | - Tanya Das
- From the Division of Molecular Medicine, Bose Institute, P1/12, Calcutta Improvement Trust Scheme VIIM, Kolkata 700054, West Bengal, India,
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10
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Shulami S, Shenker O, Langut Y, Lavid N, Gat O, Zaide G, Zehavi A, Sonenshein AL, Shoham Y. Multiple regulatory mechanisms control the expression of the Geobacillus stearothermophilus gene for extracellular xylanase. J Biol Chem 2014; 289:25957-75. [PMID: 25070894 DOI: 10.1074/jbc.m114.592873] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [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: 12/17/2022] Open
Abstract
Geobacillus stearothermophilus T-6 produces a single extracellular xylanase (Xyn10A) capable of producing short, decorated xylo-oligosaccharides from the naturally branched polysaccharide, xylan. Gel retardation assays indicated that the master negative regulator, XylR, binds specifically to xylR operators in the promoters of xylose and xylan-utilization genes. This binding is efficiently prevented in vitro by xylose, the most likely molecular inducer. Expression of the extracellular xylanase is repressed in medium containing either glucose or casamino acids, suggesting that carbon catabolite repression plays a role in regulating xynA. The global transcriptional regulator CodY was shown to bind specifically to the xynA promoter region in vitro, suggesting that CodY is a repressor of xynA. The xynA gene is located next to an uncharacterized gene, xynX, that has similarity to the NIF3 (Ngg1p interacting factor 3)-like protein family. XynX binds specifically to a 72-bp fragment in the promoter region of xynA, and the expression of xynA in a xynX null mutant appeared to be higher, indicating that XynX regulates xynA. The specific activity of the extracellular xylanase increases over 50-fold during early exponential growth, suggesting cell density regulation (quorum sensing). Addition of conditioned medium to fresh and low cell density cultures resulted in high expression of xynA, indicating that a diffusible extracellular xynA density factor is present in the medium. The xynA density factor is heat-stable, sensitive to proteases, and was partially purified using reverse phase liquid chromatography. Taken together, these results suggest that xynA is regulated by quorum-sensing at low cell densities.
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Affiliation(s)
- Smadar Shulami
- From the Department of Biotechnology and Food Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel and
| | - Ofer Shenker
- From the Department of Biotechnology and Food Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel and
| | - Yael Langut
- From the Department of Biotechnology and Food Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel and
| | - Noa Lavid
- From the Department of Biotechnology and Food Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel and
| | - Orit Gat
- From the Department of Biotechnology and Food Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel and
| | - Galia Zaide
- From the Department of Biotechnology and Food Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel and
| | - Arie Zehavi
- From the Department of Biotechnology and Food Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel and
| | - Abraham L Sonenshein
- the Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts 02111
| | - Yuval Shoham
- From the Department of Biotechnology and Food Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel and
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11
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Ruangprasert A, Maehigashi T, Miles SJ, Giridharan N, Liu JX, Dunham CM. Mechanisms of toxin inhibition and transcriptional repression by Escherichia coli DinJ-YafQ. J Biol Chem 2014; 289:20559-69. [PMID: 24898247 PMCID: PMC4110269 DOI: 10.1074/jbc.m114.573006] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [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: 04/10/2014] [Revised: 05/29/2014] [Indexed: 01/26/2023] Open
Abstract
Bacteria encounter environmental stresses that regulate a gene expression program required for adaptation and survival. Here, we report the 1.8-Å crystal structure of the Escherichia coli toxin-antitoxin complex YafQ-(DinJ)2-YafQ, a key component of the stress response. The antitoxin DinJ dimer adopts a ribbon-helix-helix motif required for transcriptional autorepression, and toxin YafQ contains a microbial RNase fold whose proposed active site is concealed by DinJ binding. Contrary to previous reports, our studies indicate that equivalent levels of transcriptional repression occur by direct interaction of either YafQ-(DinJ)2-YafQ or a DinJ dimer at a single inverted repeat of its recognition sequence that overlaps with the -10 promoter region. Surprisingly, multiple YafQ-(DinJ)2-YafQ complexes binding to the operator region do not appear to amplify the extent of repression. Our results suggest an alternative model for transcriptional autorepression that may be novel to DinJ-YafQ.
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Affiliation(s)
- Ajchareeya Ruangprasert
- From the Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Tatsuya Maehigashi
- From the Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Stacey J Miles
- From the Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Nisha Giridharan
- From the Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Julie X Liu
- From the Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Christine M Dunham
- From the Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322
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12
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Zhang L, Wei Y, Pushel I, Heinze K, Elenbaas J, Henry RW, Arnosti DN. Integrated stability and activity control of the Drosophila Rbf1 retinoblastoma protein. J Biol Chem 2014; 289:24863-73. [PMID: 25049232 DOI: 10.1074/jbc.m114.586818] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The retinoblastoma (RB) family transcriptional corepressors regulate diverse cellular events including cell cycle, senescence, and differentiation. The activity and stability of these proteins are mediated by post-translational modifications; however, we lack a general understanding of how distinct modifications coordinately impact both of these properties. Previously, we showed that protein turnover and activity are tightly linked through an evolutionarily conserved C-terminal instability element (IE) in the Drosophila RB-related protein Rbf1; surprisingly, mutant proteins with enhanced stability were less, not more active. To better understand how activity and turnover are controlled in this model RB protein, we assessed the impact of Cyclin-Cdk kinase regulation on Rbf1. An evolutionarily conserved N-terminal threonine residue is required for Cyclin-Cdk response and showed a dominant impact on turnover and activity; however, specific residues in the C-terminal IE differentially impacted Rbf1 activity and turnover, indicating an additional level of regulation. Strikingly, specific IE mutations that impaired turnover but not activity induced dramatic developmental phenotypes in the Drosophila eye. Mutation of the highly conserved Lys-774 residue induced hypermorphic phenotypes that mimicked the loss of phosphorylation control; mutation of the corresponding codon of the human RBL2 gene has been reported in lung tumors. Our data support a model in which closely intermingled residues within the conserved IE govern protein turnover, presumably through interactions with E3 ligases, and protein activity via contacts with E2F transcription partners. Such functional relationships are likely to similarly impact mammalian RB family proteins, with important implications for development and disease.
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Affiliation(s)
- Liang Zhang
- From the Cell and Molecular Biology Program and
| | - Yiliang Wei
- the Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824-1319 and
| | - Irina Pushel
- the Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824-1319 and
| | - Karolin Heinze
- the Biochemistry and Molecular Biology Program, Friedrich-Schiller University Jena, D-07743 Jena, Germany
| | - Jared Elenbaas
- the Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824-1319 and
| | - R William Henry
- From the Cell and Molecular Biology Program and the Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824-1319 and
| | - David N Arnosti
- From the Cell and Molecular Biology Program and the Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824-1319 and
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13
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Turapov O, Waddell SJ, Burke B, Glenn S, Sarybaeva AA, Tudo G, Labesse G, Young DI, Young M, Andrew PW, Butcher PD, Cohen-Gonsaud M, Mukamolova GV. Oleoyl coenzyme A regulates interaction of transcriptional regulator RaaS (Rv1219c) with DNA in mycobacteria. J Biol Chem 2014; 289:25241-9. [PMID: 25012658 PMCID: PMC4155686 DOI: 10.1074/jbc.m114.577338] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
We have recently shown that RaaS (regulator of antimicrobial-assisted survival), encoded by Rv1219c in Mycobacterium tuberculosis and by bcg_1279c in Mycobacterium bovis bacillus Calmette-Guérin, plays an important role in mycobacterial survival in prolonged stationary phase and during murine infection. Here, we demonstrate that long chain acyl-CoA derivatives (oleoyl-CoA and, to lesser extent, palmitoyl-CoA) modulate RaaS binding to DNA and expression of the downstream genes that encode ATP-dependent efflux pumps. Moreover, exogenously added oleic acid influences RaaS-mediated mycobacterial improvement of survival and expression of the RaaS regulon. Our data suggest that long chain acyl-CoA derivatives serve as biological indicators of the bacterial metabolic state. Dysregulation of efflux pumps can be used to eliminate non-growing mycobacteria.
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Affiliation(s)
- Obolbek Turapov
- From the Department of Infection, Immunity and Inflammation, University of Leicester, Leicester LE1 9HN, United Kingdom
| | - Simon J Waddell
- the Brighton and Sussex Medical School, University of Sussex, Brighton BN1 9PX, United Kingdom
| | - Bernard Burke
- From the Department of Infection, Immunity and Inflammation, University of Leicester, Leicester LE1 9HN, United Kingdom
| | - Sarah Glenn
- From the Department of Infection, Immunity and Inflammation, University of Leicester, Leicester LE1 9HN, United Kingdom
| | - Asel A Sarybaeva
- From the Department of Infection, Immunity and Inflammation, University of Leicester, Leicester LE1 9HN, United Kingdom
| | - Griselda Tudo
- the Medical Microbiology, Centre for Infection and Immunity, Division of Clinical Sciences, St. George's University of London, London SW17 0RE, United Kingdom
| | - Gilles Labesse
- the Centre de Biochimie Structurale, CNRS UMR 5048, 34090 Montpellier, France, INSERM U1054, Universités Montpellier I and II, 34090 Montpellier, France, and
| | - Danielle I Young
- the Institute of Biological, Environmental and Rural Sciences, Aberystwyth University, Aberystwyth SY23 3DD, United Kingdom
| | - Michael Young
- the Institute of Biological, Environmental and Rural Sciences, Aberystwyth University, Aberystwyth SY23 3DD, United Kingdom
| | - Peter W Andrew
- From the Department of Infection, Immunity and Inflammation, University of Leicester, Leicester LE1 9HN, United Kingdom
| | - Philip D Butcher
- the Medical Microbiology, Centre for Infection and Immunity, Division of Clinical Sciences, St. George's University of London, London SW17 0RE, United Kingdom
| | - Martin Cohen-Gonsaud
- the Centre de Biochimie Structurale, CNRS UMR 5048, 34090 Montpellier, France, INSERM U1054, Universités Montpellier I and II, 34090 Montpellier, France, and
| | - Galina V Mukamolova
- From the Department of Infection, Immunity and Inflammation, University of Leicester, Leicester LE1 9HN, United Kingdom,
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14
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Shen L, Cui A, Xue Y, Cui Y, Dong X, Gao Y, Yang H, Fang F, Chang Y. Hepatic differentiated embryo-chondrocyte-expressed gene 1 (Dec1) inhibits sterol regulatory element-binding protein-1c (Srebp-1c) expression and alleviates fatty liver phenotype. J Biol Chem 2014; 289:23332-42. [PMID: 24993831 DOI: 10.1074/jbc.m113.526343] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Hepatic steatosis, characterized by ectopic hepatic triglyceride accumulation, is considered as the early manifestation of non-alcoholic fatty liver diseases (NAFLD). Increased SREBP-1c level and activity contribute to excessive hepatic triglyceride accumulation in NAFLD patients; however, negative regulators of Srebp-1c are not well defined. In this study, we show that Dec1, a critical regulator of circadian rhythm, negatively regulates hepatic Srebp-1c expression. Hepatic Dec1 expression levels are markedly decreased in NAFLD mouse models. Restored Dec1 gene expression levels in NAFLD mouse livers decreased the expression of Srebp-1c and lipogenic genes, subsequently ameliorating the fatty liver phenotype. Conversely, knockdown of Dec1 expression by an adenovirus expressing Dec1-specific shRNA led to an increase in hepatic TG content in normal mouse livers. Correspondingly, expression levels of lipogenic genes, including Srebp-1c, Fas, and Acc, were increased in livers of mice with Dec1 knockdown. Moreover, a functional lipogenesis assay suggested that Dec1 overexpression repressed lipid synthesis in primary hepatocytes. Finally, a luciferase reporter gene assay indicates that DEC1 inhibits Srebp-1c gene transcription via the E-box mapped to the promoter region. Chromatin immunoprecipitation confirmed that DEC1 proteins bound to the identified E-box element. Our studies indicate that DEC1 is an important regulator of Srebp-1c expression and links circadian rhythm to hepatic lipogenesis. Activation of Dec1 can alleviate the nonalcoholic fatty liver phenotype.
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Affiliation(s)
- Lian Shen
- From the National Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100005, China and
| | - Anfang Cui
- the Biochemistry Department, Jining Medical University, Jining 272067, China
| | - Yuan Xue
- From the National Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100005, China and
| | - Ying Cui
- From the National Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100005, China and
| | - Xueyu Dong
- From the National Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100005, China and
| | - Yong Gao
- From the National Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100005, China and
| | - Hao Yang
- From the National Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100005, China and
| | - Fude Fang
- From the National Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100005, China and
| | - Yongsheng Chang
- From the National Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100005, China and
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15
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Chang FMJ, Coyne HJ, Cubillas C, Vinuesa P, Fang X, Ma Z, Ma D, Helmann JD, García-de los Santos A, Wang YX, Dann CE, Giedroc DP. Cu(I)-mediated allosteric switching in a copper-sensing operon repressor (CsoR). J Biol Chem 2014; 289:19204-17. [PMID: 24831014 DOI: 10.1074/jbc.m114.556704] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [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: 01/12/2023] Open
Abstract
The copper-sensing operon repressor (CsoR) is representative of a major Cu(I)-sensing family of bacterial metalloregulatory proteins that has evolved to prevent cytoplasmic copper toxicity. It is unknown how Cu(I) binding to tetrameric CsoRs mediates transcriptional derepression of copper resistance genes. A phylogenetic analysis of 227 DUF156 protein members, including biochemically or structurally characterized CsoR/RcnR repressors, reveals that Geobacillus thermodenitrificans (Gt) CsoR characterized here is representative of CsoRs from pathogenic bacilli Listeria monocytogenes and Bacillus anthracis. The 2.56 Å structure of Cu(I)-bound Gt CsoR reveals that Cu(I) binding induces a kink in the α2-helix between two conserved copper-ligating residues and folds an N-terminal tail (residues 12-19) over the Cu(I) binding site. NMR studies of Gt CsoR reveal that this tail is flexible in the apo-state with these dynamics quenched upon Cu(I) binding. Small angle x-ray scattering experiments on an N-terminally truncated Gt CsoR (Δ2-10) reveal that the Cu(I)-bound tetramer is hydrodynamically more compact than is the apo-state. The implications of these findings for the allosteric mechanisms of other CsoR/RcnR repressors are discussed.
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Affiliation(s)
- Feng-Ming James Chang
- From the Department of Chemistry, Indiana University, Bloomington, Indiana 47405-7102
| | - H Jerome Coyne
- From the Department of Chemistry, Indiana University, Bloomington, Indiana 47405-7102
| | - Ciro Cubillas
- the Programa de Ingeniería Genómica, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Apdo. Postal 565-A, Cuernavaca, Morelos, México, 04510
| | - Pablo Vinuesa
- the Programa de Ingeniería Genómica, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Apdo. Postal 565-A, Cuernavaca, Morelos, México, 04510
| | - Xianyang Fang
- the Structural Biophysics Laboratory, Center for Cancer Research, NCI-National Institutes of Health, Frederick, Maryland 21702-1201, and
| | - Zhen Ma
- the Department of Microbiology, Cornell University, Ithaca, New York 14853-8101
| | - Dejian Ma
- From the Department of Chemistry, Indiana University, Bloomington, Indiana 47405-7102
| | - John D Helmann
- the Department of Microbiology, Cornell University, Ithaca, New York 14853-8101
| | - Alejandro García-de los Santos
- the Programa de Ingeniería Genómica, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Apdo. Postal 565-A, Cuernavaca, Morelos, México, 04510
| | - Yun-Xing Wang
- the Structural Biophysics Laboratory, Center for Cancer Research, NCI-National Institutes of Health, Frederick, Maryland 21702-1201, and
| | - Charles E Dann
- From the Department of Chemistry, Indiana University, Bloomington, Indiana 47405-7102
| | - David P Giedroc
- From the Department of Chemistry, Indiana University, Bloomington, Indiana 47405-7102,
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16
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Ehrensberger KM, Corkins ME, Choi S, Bird AJ. The double zinc finger domain and adjacent accessory domain from the transcription factor loss of zinc sensing 1 (loz1) are necessary for DNA binding and zinc sensing. J Biol Chem 2014; 289:18087-96. [PMID: 24831008 DOI: 10.1074/jbc.m114.551333] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The Loz1 transcription factor from Schizosaccharomyces pombe plays an essential role in zinc homeostasis by repressing target gene expression in zinc-replete cells. To determine how Loz1 function is regulated by zinc, we employed a genetic screen to isolate mutants with impaired zinc-dependent gene expression and analyzed Loz1 protein truncations to map a minimal zinc-responsive domain. In the screen, we isolated 36 new loz1 alleles. 27 of these alleles contained mutations resulting in the truncation of the Loz1 protein. The remaining nine alleles contained point mutations leading to an amino acid substitution within a C-terminal double zinc finger domain. Further analysis of two of these substitutions revealed that they disrupted Loz1 DNA activity in vitro. By analyzing Loz1 protein truncations, we found that the last 96 amino acids of Loz1 was the smallest region that was able to confer partial zinc-dependent repression in vivo. This 96-amino acid region contains the double zinc finger domain and an accessory domain that enhances DNA binding. These results were further supported by the findings that MtfA, a transcription factor from Aspergillus nidulans that contains a related double zinc finger, is unable to complement loz1Δ, whereas a chimera of MtfA containing the Loz1 accessory domain is able to complement loz1Δ. Together, our studies indicate that the double zinc finger domain and adjacent accessory domain preceding zinc finger 1 are necessary for DNA binding and zinc-dependent repression.
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Affiliation(s)
- Kate M Ehrensberger
- From the Department of Molecular Genetics, the Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210
| | | | | | - Amanda J Bird
- From the Department of Molecular Genetics, the Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210the Department of Human Sciences, and
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17
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Choi WI, Kim MY, Jeon BN, Koh DI, Yun CO, Li Y, Lee CE, Oh J, Kim K, Hur MW. Role of promyelocytic leukemia zinc finger (PLZF) in cell proliferation and cyclin-dependent kinase inhibitor 1A (p21WAF/CDKN1A) gene repression. J Biol Chem 2014; 289:18625-40. [PMID: 24821727 DOI: 10.1074/jbc.m113.538751] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [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: 11/06/2022] Open
Abstract
Promyelocytic leukemia zinc finger (PLZF) is a transcription repressor that was initially isolated as a fusion protein with retinoic acid receptor α. PLZF is aberrantly overexpressed in various human solid tumors, such as clear cell renal carcinoma, glioblastoma, and seminoma. PLZF causes cellular transformation of NIH3T3 cells and increases cell proliferation in several cell types. PLZF also increases tumor growth in the mouse xenograft tumor model. PLZF may stimulate cell proliferation by controlling expression of the genes of the p53 pathway (ARF, TP53, and CDKN1A). We found that PLZF can directly repress transcription of CDKN1A encoding p21, a negative regulator of cell cycle progression. PLZF binds to the proximal Sp1-binding GC-box 5/6 and the distal p53-responsive elements of the CDKN1A promoter to repress transcription. Interestingly, PLZF interacts with Sp1 or p53 and competes with Sp1 or p53. PLZF interacts with corepressors, such as mSin3A, NCoR, and SMRT, thereby deacetylates Ac-H3 and Ac-H4 histones at the CDKN1A promoter, which indicated the involvement of the corepressor·HDACs complex in transcription repression by PLZF. Also, PLZF represses transcription of TP53 and also decreases p53 protein stability by ubiquitination. PLZF may act as a potential proto-oncoprotein in various cell types.
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Affiliation(s)
- Won-Il Choi
- From the Department of Biochemistry and Molecular Biology, Brain Korea 21 Plus Project for Medical Science, Severance Biomedical Research Institute, Yonsei University School of Medicine, 50 Yonsei-Ro, SeoDaeMoon-Gu, Seoul 120-752
| | - Min-Young Kim
- From the Department of Biochemistry and Molecular Biology, Brain Korea 21 Plus Project for Medical Science, Severance Biomedical Research Institute, Yonsei University School of Medicine, 50 Yonsei-Ro, SeoDaeMoon-Gu, Seoul 120-752
| | - Bu-Nam Jeon
- From the Department of Biochemistry and Molecular Biology, Brain Korea 21 Plus Project for Medical Science, Severance Biomedical Research Institute, Yonsei University School of Medicine, 50 Yonsei-Ro, SeoDaeMoon-Gu, Seoul 120-752
| | - Dong-In Koh
- From the Department of Biochemistry and Molecular Biology, Brain Korea 21 Plus Project for Medical Science, Severance Biomedical Research Institute, Yonsei University School of Medicine, 50 Yonsei-Ro, SeoDaeMoon-Gu, Seoul 120-752
| | - Chae-Ok Yun
- the Department of Bioengineering, College of Engineering, Hanyang University, 222 Wangsimni-Ro, Seongdong-Gu, Seoul 133-791, and
| | - Yan Li
- the Department of Bioengineering, College of Engineering, Hanyang University, 222 Wangsimni-Ro, Seongdong-Gu, Seoul 133-791, and
| | - Choong-Eun Lee
- the Department of Biological Science, Sungkyunkwan University, 300 Cheon-Cheon Dong, Suwon 440-746, Korea
| | - Jiyoung Oh
- the Department of Biological Science, Sungkyunkwan University, 300 Cheon-Cheon Dong, Suwon 440-746, Korea
| | - Kunhong Kim
- From the Department of Biochemistry and Molecular Biology, Brain Korea 21 Plus Project for Medical Science, Severance Biomedical Research Institute, Yonsei University School of Medicine, 50 Yonsei-Ro, SeoDaeMoon-Gu, Seoul 120-752
| | - Man-Wook Hur
- From the Department of Biochemistry and Molecular Biology, Brain Korea 21 Plus Project for Medical Science, Severance Biomedical Research Institute, Yonsei University School of Medicine, 50 Yonsei-Ro, SeoDaeMoon-Gu, Seoul 120-752,
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18
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Choi WI, Yoon JH, Kim MY, Koh DI, Licht JD, Kim K, Hur MW. Promyelocytic leukemia zinc finger-retinoic acid receptor α (PLZF-RARα), an oncogenic transcriptional repressor of cyclin-dependent kinase inhibitor 1A (p21WAF/CDKN1A) and tumor protein p53 (TP53) genes. J Biol Chem 2014; 289:18641-56. [PMID: 24821728 DOI: 10.1074/jbc.m113.538777] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [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: 11/06/2022] Open
Abstract
Promyelocytic leukemia zinc finger-retinoic acid receptor α (PLZF-RARα) is an oncogene transcriptional repressor that is generated by a chromosomal translocation between the PLZF and RARα genes in acute promyelocytic leukemia (APL-type) patients. The molecular interaction between PLZF-RARα and the histone deacetylase corepressor was proposed to be important in leukemogenesis. We found that PLZF-RARα can repress transcription of the p21WAF/CDKN1A gene, which encodes the negative cell cycle regulator p21 by binding to its proximal promoter Sp1-binding GC-boxes 3, 4, 5/6, a retinoic acid response element (RARE), and distal p53-responsive elements (p53REs). PLZF-RARα also acts as a competitive transcriptional repressor of p53, RARα, and Sp1. PLZF-RARα interacts with co-repressors such as mSin3A, NCoR, and SMRT, thereby deacetylating histones Ac-H3 and Ac-H4 at the CDKN1A promoter. PLZF-RARα also interacts with the MBD3-NuRD complex, leading to epigenetic silencing of CDKN1A through DNA methylation. Furthermore, PLZF-RARα represses TP53 and increases p53 protein degradation by ubiquitination, further repressing p21 expression. Resultantly, PLZF-RARα promotes cell proliferation and significantly increases the number of cells in S-phase.
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Affiliation(s)
- Won-Il Choi
- From the Department of Biochemistry and Molecular Biology, Brain Korea 21 Plus Project for Medical Science, Severance Biomedical Science Institute, Yonsei University School of Medicine, 50 Yonsei-Ro, SeoDaeMoon-Gu, Seoul 120-752, Korea and
| | - Jae-Hyeon Yoon
- From the Department of Biochemistry and Molecular Biology, Brain Korea 21 Plus Project for Medical Science, Severance Biomedical Science Institute, Yonsei University School of Medicine, 50 Yonsei-Ro, SeoDaeMoon-Gu, Seoul 120-752, Korea and
| | - Min-Young Kim
- From the Department of Biochemistry and Molecular Biology, Brain Korea 21 Plus Project for Medical Science, Severance Biomedical Science Institute, Yonsei University School of Medicine, 50 Yonsei-Ro, SeoDaeMoon-Gu, Seoul 120-752, Korea and
| | - Dong-In Koh
- From the Department of Biochemistry and Molecular Biology, Brain Korea 21 Plus Project for Medical Science, Severance Biomedical Science Institute, Yonsei University School of Medicine, 50 Yonsei-Ro, SeoDaeMoon-Gu, Seoul 120-752, Korea and
| | - Jonathan D Licht
- the Division of Hematology/Oncology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611
| | - Kunhong Kim
- From the Department of Biochemistry and Molecular Biology, Brain Korea 21 Plus Project for Medical Science, Severance Biomedical Science Institute, Yonsei University School of Medicine, 50 Yonsei-Ro, SeoDaeMoon-Gu, Seoul 120-752, Korea and
| | - Man-Wook Hur
- From the Department of Biochemistry and Molecular Biology, Brain Korea 21 Plus Project for Medical Science, Severance Biomedical Science Institute, Yonsei University School of Medicine, 50 Yonsei-Ro, SeoDaeMoon-Gu, Seoul 120-752, Korea and
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19
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Aninye IO, Matsumoto S, Sidhaye AR, Wondisford FE. Circadian regulation of Tshb gene expression by Rev-Erbα (NR1D1) and nuclear corepressor 1 (NCOR1). J Biol Chem 2014; 289:17070-7. [PMID: 24794873 DOI: 10.1074/jbc.m114.569723] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [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] Open
Abstract
Thyroid hormones (TH) are critical for development, growth, and metabolism. Circulating TH levels are tightly regulated by thyroid-stimulating hormone (TSH) secretion within the hypothalamic-pituitary-thyroid axis. Although circadian TSH secretion has been well documented, the mechanism of this observation remains unclear. Recently, the nuclear corepressor, NCOR1, has been postulated to regulate TSH expression, presumably by interacting with thyroid hormone receptors (THRs) bound to TSH subunit genes. We report herein the first in vitro study of NCOR1 regulation of TSH in a physiologically relevant cell system, the TαT1.1 mouse thyrotroph cell line. Knockdown of NCOR1 by shRNA adenovirus increased baseline Tshb mRNA levels compared with scrambled control, but surprisingly had no affect on the T3-mediated repression of this gene. Using ChIP, we show that NCOR1 enriches on the Tshb promoter at sites different from THR previously identified by our group. Furthermore, NCOR1 enrichment on Tshb is unaffected by T3 treatment. Given that NCOR1 does not target THR on Tshb, we hypothesized that NCOR1 targeted Rev-Erbα (NR1D1), an orphan nuclear receptor that is a potent repressor of gene transcription and regulator of metabolism and circadian rhythms. Using a serum shock technique, we synchronized TαT1.1 cells to study circadian gene expression. Post-synchronization, Tshb and Nr1d1 mRNA levels displayed oscillations that inversely correlated with each other. Furthermore, NR1D1 was enriched at the same locus as NCOR1 on Tshb. Therefore, we propose a model for Tshb regulation whereby NR1D1 and NCOR1 interact to regulate circadian expression of Tshb independent of TH negative regulation.
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Affiliation(s)
- Irene O Aninye
- From the Division of Metabolism, Departments of Pediatrics, Physiology, and Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21287
| | - Shunichi Matsumoto
- From the Division of Metabolism, Departments of Pediatrics, Physiology, and Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21287
| | - Aniket R Sidhaye
- From the Division of Metabolism, Departments of Pediatrics, Physiology, and Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21287
| | - Fredric E Wondisford
- From the Division of Metabolism, Departments of Pediatrics, Physiology, and Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21287
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20
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Gu X, Hu Z, Ebrahem Q, Crabb JS, Mahfouz RZ, Radivoyevitch T, Crabb JW, Saunthararajah Y. Runx1 regulation of Pu.1 corepressor/coactivator exchange identifies specific molecular targets for leukemia differentiation therapy. J Biol Chem 2014; 289:14881-95. [PMID: 24695740 DOI: 10.1074/jbc.m114.562447] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [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: 12/28/2022] Open
Abstract
Gene activation requires cooperative assembly of multiprotein transcription factor-coregulator complexes. Disruption to cooperative assemblage could underlie repression of tumor suppressor genes in leukemia cells. Mechanisms of cooperation and its disruption were therefore examined for PU.1 and RUNX1, transcription factors that cooperate to activate hematopoietic differentiation genes. PU.1 is highly expressed in leukemia cells, whereas RUNX1 is frequently inactivated by mutation or translocation. Thus, coregulator interactions of Pu.1 were examined by immunoprecipitation coupled with tandem mass spectrometry/Western blot in wild-type and Runx1-deficient hematopoietic cells. In wild-type cells, the NuAT and Baf families of coactivators coimmunoprecipitated with Pu.1. Runx1 deficiency produced a striking switch to Pu.1 interaction with the Dnmt1, Sin3A, Nurd, CoRest, and B-Wich corepressor families. Corepressors of the Polycomb family, which are frequently inactivated by mutation or deletion in myeloid leukemia, did not interact with Pu.1. The most significant gene ontology association of Runx1-Pu.1 co-bound genes was with macrophages, therefore, functional consequences of altered corepressor/coactivator exchange were examined at Mcsfr, a key macrophage differentiation gene. In chromatin immunoprecipitation analyses, high level Pu.1 binding to the Mcsfr promoter was not decreased by Runx1 deficiency. However, the Pu.1-driven shift from histone repression to activation marks at this locus, and terminal macrophage differentiation, were substantially diminished. DNMT1 inhibition, but not Polycomb inhibition, in RUNX1-translocated leukemia cells induced terminal differentiation. Thus, RUNX1 and PU.1 cooperate to exchange corepressors for coactivators, and the specific corepressors recruited to PU.1 as a consequence of RUNX1 deficiency could be rational targets for leukemia differentiation therapy.
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Affiliation(s)
- Xiaorong Gu
- From the Department of Translational Hematology and Oncology Research, Taussig Cancer Institute, and
| | - Zhenbo Hu
- From the Department of Translational Hematology and Oncology Research, Taussig Cancer Institute, and
| | - Quteba Ebrahem
- From the Department of Translational Hematology and Oncology Research, Taussig Cancer Institute, and
| | - John S Crabb
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio 44195 and
| | - Reda Z Mahfouz
- From the Department of Translational Hematology and Oncology Research, Taussig Cancer Institute, and
| | - Tomas Radivoyevitch
- the Department of Epidemiology and Biostatistics, Case Western Reserve University, Cleveland, Ohio 44106
| | - John W Crabb
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio 44195 and
| | - Yogen Saunthararajah
- From the Department of Translational Hematology and Oncology Research, Taussig Cancer Institute, and
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21
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Nagpal K, Watanabe KS, Tsao BP, Tsokos GC. Transcription factor Ikaros represses protein phosphatase 2A (PP2A) expression through an intronic binding site. J Biol Chem 2014; 289:13751-7. [PMID: 24692537 DOI: 10.1074/jbc.m114.558197] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [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: 01/15/2023] Open
Abstract
Protein phosphatase 2A (PP2A) is a highly conserved and ubiquitous serine/threonine phosphatase. We have shown previously that PP2A expression is increased in T cells of systemic lupus erythematosus patients and that this increased expression and activity of PP2A plays a central role in the molecular pathogenesis of systemic lupus erythematosus. Although the control of PP2A expression has been the focus of many studies, many aspects of its regulation still remain poorly understood. In this study, we describe a novel mechanism of PP2A regulation. We propose that the transcription factor Ikaros binds to a variant site in the first intron of PP2A and modulates its expression. Exogenous expression of Ikaros leads to reduced levels of PP2Ac message as well as protein. Conversely, siRNA-enabled silencing of Ikaros enhances the expression of PP2A, suggesting that Ikaros acts as a suppressor of PP2A expression. A ChIP analysis further proved that Ikaros is recruited to this site in T cells. We also attempted to delineate the mechanism of Ikaros-mediated PP2Ac gene suppression. We show that Ikaros-mediated suppression of PP2A expression is at least partially dependent on the recruitment of the histone deacetylase HDAC1 to this intronic site. We conclude that the transcription factor Ikaros can regulate the expression of PP2A by binding to a site in the first intron and modulating chromatin modifications at this site via recruitment of HDAC1.
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Affiliation(s)
- Kamalpreet Nagpal
- From the Department of Medicine, Division of Rheumatology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02115 and
| | - Katsue Sunahori Watanabe
- From the Department of Medicine, Division of Rheumatology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02115 and
| | - Betty P Tsao
- the Division of Rheumatology, University of California Los Angeles, Los Angeles, California 90095
| | - George C Tsokos
- From the Department of Medicine, Division of Rheumatology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02115 and
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22
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Wu J, Bowe DB, Sadlonova A, Whisenhunt TR, Hu Y, Rustgi AK, Nie Y, Paterson AJ, Yang X. O-GlcNAc transferase is critical for transducin-like enhancer of split (TLE)-mediated repression of canonical Wnt signaling. J Biol Chem 2014; 289:12168-12176. [PMID: 24616106 DOI: 10.1074/jbc.m114.553859] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The Drosophila Groucho protein and its mammalian orthologues the transducin-like enhancers of split (TLEs) are critical transcriptional corepressors that repress Wnt and other signaling pathways. Although it is known that Groucho/TLEs are recruited to target genes by pathway-specific transcription factors, molecular events after the corepressor recruitment are largely unclear. We report that association of TLEs with O-GlcNAc transferase, an enzyme that catalyzes posttranslational modification of proteins by O-linked N-acetylglucosamine, is essential for TLE-mediated transcriptional repression. Removal of O-GlcNAc from Wnt-responsive gene promoters is critical for gene activation from Wnt-responsive promoters. Thus, these studies identify a molecular mechanism by which Groucho/TLEs repress gene transcription and provide a model whereby O-GlcNAc may control distinct intracellular signaling pathways.
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Affiliation(s)
- Jing Wu
- Center for Mitochondrial Biology and Medicine, the Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology and Frontier Institute of Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China; Section of Comparative Medicine and Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, Connecticut 06519
| | - Damon B Bowe
- Division of Endocrinology and Metabolism, University of Alabama at Birmingham, Birmingham, Alabama 35294
| | - Andrea Sadlonova
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia 30322
| | - Thomas R Whisenhunt
- Division of Endocrinology and Metabolism, University of Alabama at Birmingham, Birmingham, Alabama 35294
| | - Yong Hu
- Division of Endocrinology and Metabolism, University of Alabama at Birmingham, Birmingham, Alabama 35294
| | - Anil K Rustgi
- Department of Medicine (GI) and Genetics, Abramson Cancer Center, 600 CRB, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Yongzhan Nie
- State Key Laboratory of Cancer Biology and Xijing Hospital of Digestive Diseases, Fourth Military Medical University, 127 West Changle Road, Xi'an, Shaanxi 710032, China
| | - Andrew J Paterson
- Division of Endocrinology and Metabolism, University of Alabama at Birmingham, Birmingham, Alabama 35294
| | - Xiaoyong Yang
- Section of Comparative Medicine and Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, Connecticut 06519.
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23
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Dhar SS, Alam H, Li N, Wagner KW, Chung J, Ahn YW, Lee MG. Transcriptional repression of histone deacetylase 3 by the histone demethylase KDM2A is coupled to tumorigenicity of lung cancer cells. J Biol Chem 2014; 289:7483-96. [PMID: 24482232 DOI: 10.1074/jbc.m113.521625] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Dysregulated expression of histone methyltransferases and demethylases is an emerging epigenetic mechanism underlying cancer development and metastasis. We recently showed that the histone H3 lysine 36 (H3K36) demethylase KDM2A (also called FBXL11 and JHDM1A) is necessary for tumorigenic and metastatic capabilities of KDM2A-overexpressing non-small cell lung cancer (NSCLC) cells. Here, we report that KDM2A transcriptionally represses the histone deacetylase 3 (HDAC3) gene by removing methyl groups from dimethylated H3K36 at the HDAC3 promoter in KDM2A-overexpressing NSCLC cells. KDM2A depletion reduced expression levels of cell cycle-associated genes (e.g. CDK6) and cell invasion-related genes (e.g. NANOS1); these levels were rescued by ectopic expression of KDM2A but not its catalytic mutant. These genes were occupied and down-regulated by HDAC3. HDAC3 knockdown significantly recovered the proliferation and invasiveness of KDM2A-depleted NSCLC cells as well as the levels of CDK6 and NANOS1 expression in these cells. Similar to their previously reported functions in other cell types, CDK6 and NANOS1 were required for the proliferation and invasion, respectively, of KDM2A-overexpressing NSCLC cells. In a mouse xenograft model, HDAC3 depletion substantially restored the tumorigenic ability of KDM2A knockdown cells. These findings reveal a novel cancer-epigenetic pathway in which the antagonistic effect of KDM2A on HDAC3 expression releases cell cycle-associated genes and cell invasion-related genes from HDAC3 repression and indicate the importance of this pathway for tumorigenicity and invasiveness of KDM2A-overexpressing NSCLC cells.
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Affiliation(s)
- Shilpa S Dhar
- From the Department of Molecular and Cellular Oncology and
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24
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Annayev Y, Adar S, Chiou YY, Lieb JD, Sancar A, Ye R. Gene model 129 (Gm129) encodes a novel transcriptional repressor that modulates circadian gene expression. J Biol Chem 2014; 289:5013-24. [PMID: 24385426 DOI: 10.1074/jbc.m113.534651] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [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: 12/22/2022] Open
Abstract
The mammalian circadian clock is a molecular oscillator composed of a feedback loop that involves transcriptional activators CLOCK and BMAL1, and repressors Cryptochrome (CRY) and Period (PER). Here we show that a direct CLOCK·BMAL1 target gene, Gm129, is a novel regulator of the feedback loop. ChIP analysis revealed that the CLOCK·BMAL1·CRY1 complex strongly occupies the promoter region of Gm129. Both mRNA and protein levels of GM129 exhibit high amplitude circadian oscillations in mouse liver, and Gm129 gene encodes a nuclear-localized protein that directly interacts with BMAL1 and represses CLOCK·BMAL1 activity. In vitro and in vivo protein-DNA interaction results demonstrate that, like CRY1, GM129 functions as a repressor by binding to the CLOCK·BMAL1 complex on DNA. Although Gm129(-/-) or Cry1(-/-) Gm129(-/-) mice retain a robust circadian rhythm, the peaks of Nr1d1 and Dbp mRNAs in liver exhibit a significant phase delay compared with control. Our results suggest that, in addition to CRYs and PERs, the GM129 protein contributes to the transcriptional feedback loop by modulating CLOCK·BMAL1 activity as a transcriptional repressor.
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Affiliation(s)
- Yunus Annayev
- From the Departments of Biochemistry and Biophysics and
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25
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An HT, Kim J, Yoo S, Ko J. Small leucine zipper protein (sLZIP) negatively regulates skeletal muscle differentiation via interaction with α-actinin-4. J Biol Chem 2013; 289:4969-79. [PMID: 24375477 DOI: 10.1074/jbc.m113.515395] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The small leucine zipper protein (sLZIP) plays a role in transcriptional regulation in various types of cells. However, the role of sLZIP in myogenesis is unknown. We identified α-actinin-4 (ACTN4) as a sLZIP-binding protein. ACTN4 functions as a transcriptional regulator of myocyte enhancer factor (MEF)2, which plays a critical role in expression of muscle-specific genes during skeletal muscle differentiation. We found that ACTN4 translocates to the nucleus, induces myogenic gene expression, and promotes myotube formation during myogenesis. The myogenic process is controlled by an association between myogenic factors and MEF2 transcription factors. ACTN4 increased expression of muscle-specific proteins via interaction with MEF2. However, sLZIP decreased myogenic gene expression and myotube formation during myogenesis via disruption of the association between ACTN4 and MEF2. ACTN4 increased the promoter activities of myogenic genes, whereas sLZIP abrogated the effect of ACTN4 on transcriptional activation of myogenic genes in myoblasts. The C terminus of sLZIP is required for interaction with the C terminus of ACTN4, based on deletion mutant analysis, and sLZIP plays a role in regulation of MEF2 transactivation via interaction with ACTN4. Our results indicate that sLZIP negatively regulates skeletal muscle differentiation via interaction with ACTN4 and that sLZIP can be used as a therapeutic target molecule for treatment of muscle hypertrophy and associated diseases.
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Affiliation(s)
- Hyoung-Tae An
- From the Division of Life Sciences, Korea University, Seoul 136-701, South Korea
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26
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Feng Y, Wu H, Xu Y, Zhang Z, Liu T, Lin X, Feng XH. Zinc finger protein 451 is a novel Smad corepressor in transforming growth factor-β signaling. J Biol Chem 2013; 289:2072-83. [PMID: 24324267 DOI: 10.1074/jbc.m113.526905] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [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: 01/07/2023] Open
Abstract
ZNF451 is a transcriptional cofactor localized to promyelocytic leukemia bodies. Here, we present evidence demonstrating that ZNF451 physically interacts with Smad3/4 and functionally inhibits TGF-β signaling. Increased expression of ZNF451 attenuates TGF-β-induced growth inhibitory and gene transcriptional responses, whereas depletion of ZNF451 enhances TGF-β responses. Mechanistically, ZNF451 blocks the ability of Smad3/4 to recruit p300 in response to TGF-β, which causes reduction of histone H3K9 acetylation on the promoters of TGF-β target genes. Taken together, ZNF451 acts as a transcriptional corepressor for Smad3/4 and negatively regulates TGF-β signaling.
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Affiliation(s)
- Yili Feng
- From the Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang 310058, China and
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27
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Gao P, Yoo SH, Lee KJ, Rosensweig C, Takahashi JS, Chen BP, Green CB. Phosphorylation of the cryptochrome 1 C-terminal tail regulates circadian period length. J Biol Chem 2013; 288:35277-86. [PMID: 24158435 PMCID: PMC3853276 DOI: 10.1074/jbc.m113.509604] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [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] [Indexed: 01/06/2023] Open
Abstract
The Cryptochrome (CRY) proteins are critical components of the mammalian circadian clock and act to rhythmically repress the activity of the transcriptional activators CLOCK and BMAL1 at the heart of the clock mechanism. The CRY proteins are part of a large repressive complex, the components of which are not completely known. Using mass spectroscopy, we identified the catalytic subunit of DNA-dependent protein kinase as a CRY-interacting protein and found that loss or inhibition of this kinase results in circadian rhythms with abnormally long periods. We then identified serine 588 in the C-terminal tail of mouse CRY1 as a potential DNA-PK phosphorylation site but surprisingly found that the phosphomimetic mutation S588D also results in long period rhythms, similar to the loss of DNA-PK. Consistent with this, we found that phosphorylation of this site is increased in cells lacking DNA-PK, suggesting that DNA-PK negatively regulates the phosphorylation of this site most likely through indirect means. Furthermore, we found that phosphorylation of this site increases the stability of the CRY1 protein and prevents FBXL3-mediated degradation. The phosphorylation of this site is robustly rhythmic in mouse liver nuclei, peaking in the middle of the circadian day at a time when CRY1 levels are declining. Therefore, these data suggest a new role for the C-terminal tail of CRY1 in which phosphorylation rhythmically regulates CRY1 stability and contributes to the proper circadian period length.
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Affiliation(s)
- Peng Gao
- From the Department of Neuroscience, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390
| | - Seung-Hee Yoo
- From the Department of Neuroscience, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390
- the Howard Hughes Medical Institute, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390, and
| | - Kyung-Jong Lee
- the Department of Radiation Oncology, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390
| | - Clark Rosensweig
- From the Department of Neuroscience, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390
| | - Joseph S. Takahashi
- From the Department of Neuroscience, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390
- the Howard Hughes Medical Institute, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390, and
| | - Benjamin P. Chen
- the Department of Radiation Oncology, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390
| | - Carla B. Green
- From the Department of Neuroscience, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390
- To whom correspondence should be addressed: Dept. of Neuroscience, ND4.124A, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390-9111. Tel.: 214-648-7433; Fax: 214-648-1801; E-mail:
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28
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Lee JM, Gang GT, Kim DK, Kim YD, Koo SH, Lee CH, Choi HS. Ursodeoxycholic acid inhibits liver X receptor α-mediated hepatic lipogenesis via induction of the nuclear corepressor SMILE. J Biol Chem 2013; 289:1079-91. [PMID: 24265317 DOI: 10.1074/jbc.m113.491522] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Small heterodimer partner interacting leucine zipper protein (SMILE) has been identified as a nuclear corepressor of the nuclear receptor (NRs) family. Here, we examined the role of SMILE in the regulation of nuclear receptor liver X receptor (LXR)-mediated sterol regulatory element binding protein-1c (SREBP-1c) gene expression. We found that SMILE inhibited T0901317 (T7)-induced transcriptional activity of LXR, which functions as a major regulator of lipid metabolism by inducing SREBP-1c, fatty acid synthase (FAS), and acetyl-CoA carboxylase (ACC) gene expression. Moreover, we demonstrated that SMILE physically interacts with LXR and represses T7-induced LXR transcriptional activity by competing with coactivator SRC-1. Adenoviral overexpression of SMILE (Ad-SMILE) attenuated fat accumulation and lipogenic gene induction in the liver of T7 administered or of high fat diet (HFD)-fed mice. Furthermore, we investigated the mechanism by which ursodeoxycholic acid (UDCA) inhibits LXR-induced lipogenic gene expression. Interestingly, UDCA treatment significantly increased SMILE promoter activity and gene expression in an adenosine monophosphate-activated kinase-dependent manner. Furthermore, UDCA treatment repressed T7-induced SREBP-1c, FAS, and ACC protein levels, whereas knockdown of endogenous SMILE gene expression by adenovirus SMILE shRNA (Ad-shSMILE) significantly reversed UDCA-mediated repression of SREBP-1c, FAS, and ACC protein levels. Collectively, these results demonstrate that UDCA activates SMILE gene expression through adenosine monophosphate-activated kinase phosphorylation, which leads to repression of LXR-mediated hepatic lipogenic enzyme gene expression.
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Affiliation(s)
- Ji-Min Lee
- From the National Creative Research Initiatives Center for Nuclear Receptor Signals and
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29
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Tang M, Shen H, Jin Y, Lin T, Cai Q, Pinard MA, Biswas S, Tran Q, Li G, Shenoy AK, Tongdee E, Lin S, Gu Y, Law BK, Zhou L, Mckenna R, Wu L, Lu J. The malignant brain tumor (MBT) domain protein SFMBT1 is an integral histone reader subunit of the LSD1 demethylase complex for chromatin association and epithelial-to-mesenchymal transition. J Biol Chem 2013; 288:27680-27691. [PMID: 23928305 DOI: 10.1074/jbc.m113.482349] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Chromatin readers decipher the functional readouts of histone modifications by recruiting specific effector complexes for subsequent epigenetic reprogramming. The LSD1 (also known as KDM1A) histone demethylase complex modifies chromatin and represses transcription in part by catalyzing demethylation of dimethylated histone H3 lysine 4 (H3K4me2), a mark for active transcription. However, none of its currently known subunits recognizes methylated histones. The Snai1 family transcription factors are central drivers of epithelial-to-mesenchymal transition (EMT) by which epithelial cells acquire enhanced invasiveness. Snai1-mediated transcriptional repression of epithelial genes depends on its recruitment of the LSD1 complex and ensuing demethylation of H3K4me2 at its target genes. Through biochemical purification, we identified the MBT domain-containing protein SFMBT1 as a novel component of the LSD1 complex associated with Snai1. Unlike other mammalian MBT domain proteins characterized to date that selectively recognize mono- and dimethylated lysines, SFMBT1 binds di- and trimethyl H3K4, both of which are enriched at active promoters. We show that SFMBT1 is essential for Snai1-dependent recruitment of LSD1 to chromatin, demethylation of H3K4me2, transcriptional repression of epithelial markers, and induction of EMT by TGFβ. Carcinogenic metal nickel is a widespread environmental and occupational pollutant. Nickel alters gene expression and induces EMT. We demonstrate the nickel-initiated effects are dependent on LSD1-SFMBT1-mediated chromatin modification. Furthermore, in human cancer, expression of SFMBT1 is associated with mesenchymal markers and unfavorable prognosis. These results highlight a critical role of SFMBT1 in epigenetic regulation, EMT, and cancer.
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Affiliation(s)
- Ming Tang
- Department of Biochemistry and Molecular Biology; Genetics and Genomics Graduate Program, Genetics Institute, University of Florida, Gainesville, Florida 32610
| | - Huangxuan Shen
- Department of Molecular Genetics and Microbiology; State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, 510060 China
| | - Yue Jin
- Department of Biochemistry and Molecular Biology
| | - Tong Lin
- Department of Biochemistry and Molecular Biology; Genetics and Genomics Graduate Program, Genetics Institute, University of Florida, Gainesville, Florida 32610
| | - Qingsong Cai
- Department of Biochemistry and Molecular Biology
| | | | | | - Quyen Tran
- Agnes Scott College, Decatur, Georgia 30030
| | - Guangyao Li
- Genetics and Genomics Graduate Program, Genetics Institute, University of Florida, Gainesville, Florida 32610; Department of Molecular Genetics and Microbiology
| | | | | | - Shuibin Lin
- Department of Molecular Genetics and Microbiology
| | - Yumei Gu
- Department of Molecular Genetics and Microbiology
| | - Brian K Law
- Department of Pharmacology and Therapeutics, Health Cancer Center, University of Florida College of Medicine, Gainesville, Florida 32610
| | - Lei Zhou
- Genetics and Genomics Graduate Program, Genetics Institute, University of Florida, Gainesville, Florida 32610; Department of Molecular Genetics and Microbiology
| | | | - Lizi Wu
- Genetics and Genomics Graduate Program, Genetics Institute, University of Florida, Gainesville, Florida 32610; Department of Molecular Genetics and Microbiology.
| | - Jianrong Lu
- Department of Biochemistry and Molecular Biology; Genetics and Genomics Graduate Program, Genetics Institute, University of Florida, Gainesville, Florida 32610.
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30
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Natarajan M, Schiralli Lester GM, Lee C, Missra A, Wasserman GA, Steffen M, Gilmour DS, Henderson AJ. Negative elongation factor (NELF) coordinates RNA polymerase II pausing, premature termination, and chromatin remodeling to regulate HIV transcription. J Biol Chem 2013; 288:25995-26003. [PMID: 23884411 DOI: 10.1074/jbc.m113.496489] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
A barrier to eradicating HIV infection is targeting and eliminating latently infected cells. Events that contribute to HIV transcriptional latency include repressive chromatin structure, transcriptional interference, the inability of Tat to recruit positive transcription factor b, and poor processivity of RNA polymerase II (RNAP II). In this study, we investigated mechanisms by which negative elongation factor (NELF) establishes and maintains HIV latency. Negative elongation factor (NELF) induces RNAP II promoter proximal pausing and limits provirus expression in HIV-infected primary CD4(+) T cells. Decreasing NELF expression overcomes RNAP II pausing to enhance HIV transcription elongation in infected primary T cells, demonstrating the importance of pausing in repressing HIV transcription. We also show that RNAP II pausing is coupled to premature transcription termination and chromatin remodeling. NELF interacts with Pcf11, a transcription termination factor, and diminishing Pcf11 in primary CD4(+) T cells induces HIV transcription elongation. In addition, we identify NCoR1-GPS2-HDAC3 as a NELF-interacting corepressor complex that is associated with repressed HIV long terminal repeats. We propose a model in which NELF recruits Pcf11 and NCoR1-GPS2-HDAC3 to paused RNAP II, reinforcing repression of HIV transcription and establishing a critical checkpoint for HIV transcription and latency.
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Affiliation(s)
- Malini Natarajan
- From the Immunology and Infectious Diseases, Integrated Biosciences Graduate Program, Penn State University, University Park, Pennsylvania 16802,; the Departments of Medicine and Infectious Diseases
| | | | - Chanhyo Lee
- the Departments of Medicine and Infectious Diseases
| | - Anamika Missra
- the Department of Biochemistry and Molecular Biology, Penn State University, University Park, Pennsylvania 16802
| | | | - Martin Steffen
- Pathology and Laboratory Medicine, Boston University School of Medicine, Boston, Massachusetts 02118 and
| | - David S Gilmour
- the Department of Biochemistry and Molecular Biology, Penn State University, University Park, Pennsylvania 16802
| | - Andrew J Henderson
- the Departments of Medicine and Infectious Diseases,; Microbiology, and.
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31
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Lee MT, Leung YK, Chung I, Tarapore P, Ho SM. Estrogen receptor β (ERβ1) transactivation is differentially modulated by the transcriptional coregulator Tip60 in a cis-acting element-dependent manner. J Biol Chem 2013; 288:25038-25052. [PMID: 23857583 DOI: 10.1074/jbc.m113.476952] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [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: 12/19/2022] Open
Abstract
Estrogen receptor (ER) β1 and ERα have overlapping and distinct functions despite their common use of estradiol as the physiological ligand. These attributes are explained in part by their differential utilization of coregulators and ligands. Although Tip60 has been shown to interact with both receptors, its regulatory role in ERβ1 transactivation has not been defined. In this study, we found that Tip60 enhances transactivation of ERβ1 at the AP-1 site but suppresses its transcriptional activity at the estrogen-response element (ERE) site in an estradiol-independent manner. However, different estrogenic compounds can modify the Tip60 action. The corepressor activity of Tip60 at the ERE site is abolished by diarylpropionitrile, genistein, equol, and bisphenol A, whereas its coactivation at the AP-1 site is augmented by fulvestrant (ICI 182,780). GRIP1 is an important tethering mediator for ERs at the AP-1 site. We found that coexpression of GRIP1 synergizes the action of Tip60. Although Tip60 is a known acetyltransferase, it is unable to acetylate ERβ1, and its coregulatory functions are independent of its acetylation activity. In addition, we showed the co-occupancy of ERβ1 and Tip60 at ERE and AP-1 sites of ERβ1 target genes. Tip60 differentially regulates the endogenous expression of the target genes by modulating the binding of ERβ1 to the cis-regulatory regions. Thus, we have identified Tip60 as the first dual-function coregulator of ERβ1.
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Affiliation(s)
- Ming-Tsung Lee
- From the Division of Environmental Genetics and Molecular Toxicology, Department of Environmental Health
| | - Yuet-Kin Leung
- From the Division of Environmental Genetics and Molecular Toxicology, Department of Environmental Health,; Center for Environmental Genetics, and; Cancer Institute, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267 and
| | - Irving Chung
- From the Division of Environmental Genetics and Molecular Toxicology, Department of Environmental Health
| | - Pheruza Tarapore
- From the Division of Environmental Genetics and Molecular Toxicology, Department of Environmental Health,; Center for Environmental Genetics, and; Cancer Institute, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267 and
| | - Shuk-Mei Ho
- From the Division of Environmental Genetics and Molecular Toxicology, Department of Environmental Health,; Center for Environmental Genetics, and; Cancer Institute, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267 and; the Cincinnati Veteran Affairs Medical Center, Cincinnati, Ohio 45220.
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Liu B, Shats I, Angus SP, Gatza ML, Nevins JR. Interaction of E2F7 transcription factor with E2F1 and C-terminal-binding protein (CtBP) provides a mechanism for E2F7-dependent transcription repression. J Biol Chem 2013; 288:24581-9. [PMID: 23853115 DOI: 10.1074/jbc.m113.467506] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [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: 01/26/2023] Open
Abstract
Previous work has identified distinct functions for E2F proteins during a cellular proliferative response including a role for E2F1-3 in the activation of transcription at G1/S and a role for E2F4-8 in repressing the same group of E2F1-3 target genes as cells progress through S phase. We now find that E2F7 and E2F8, which are induced by E2F1-3 at G1/S, can form a heterodimer with E2F1 through interactions involving the DNA-binding domains of the two proteins. In vitro DNA interaction assays demonstrate the formation of an E2F1-E2F7 complex, as well as an E2F7-E2F7 complex on adjacent E2F-binding sites. We also show that E2F7 recruits the co-repressor C-terminal-binding protein (CtBP) and that CtBP2 is essential for E2F7 to repress E2F1 transcription. Taken together, these findings suggest a mechanism for the repression of transcription by E2F7.
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Affiliation(s)
- Beiyu Liu
- Duke Institute for Genome Sciences and Policy, Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina 27708, USA
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Rohira AD, Chen CY, Allen JR, Johnson DL. Covalent small ubiquitin-like modifier (SUMO) modification of Maf1 protein controls RNA polymerase III-dependent transcription repression. J Biol Chem 2013; 288:19288-95. [PMID: 23673667 DOI: 10.1074/jbc.m113.473744] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [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: 11/06/2022] Open
Abstract
RNA polymerase (pol) III transcribes genes that determine biosynthetic capacity. Induction of these genes is required for oncogenic transformation. The transcriptional repressor, Maf1, plays a central role in the repression of these and other genes that promote oncogenesis. Our studies identify an important new role for SUMOylation in repressing RNA pol III-dependent transcription. We show that a key mechanism by which this occurs is through small ubiquitin-like modifier (SUMO) modification of Maf1 by both SUMO1 and SUMO2. Mutation of each lysine residue revealed that Lys-35 is the major SUMOylation site on Maf1 and that the deSUMOylase, SENP1, is responsible for controlling Maf1K35 SUMOylation. SUMOylation of Maf1 is unaffected by rapamycin inhibition of mammalian target of rapamycin (mTOR) and mTOR-dependent Maf1 phosphorylation. By preventing SUMOylation at Lys-35, Maf1 is impaired in its ability to both repress transcription and suppress colony growth. Although SUMOylation does not alter Maf1 subcellular localization, Maf1K35R is defective in its ability to associate with RNA pol III. This impairs Maf1 recruitment to tRNA gene promoters and its ability to facilitate the dissociation of RNA pol III from these promoters. These studies identify a novel role for SUMOylation in controlling Maf1 and RNA pol III-mediated transcription. Given the emerging roles of SENP1, Maf1, and RNA pol III transcription in oncogenesis, our studies support the idea that deSUMOylation of Maf1 and induction of its gene targets play a critical role in cancer development.
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Affiliation(s)
- Aarti D Rohira
- Department of Biochemistry and Molecular Biology, Keck School of Medicine, University of Southern California and the Norris Comprehensive Cancer Center, Los Angeles, California 90033, USA
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Abstract
BACKGROUND Little is known about how bacteria sense or respond to reactive chlorine species, such as bleach. RESULTS NemR is a redox-regulated transcription factor which senses bleach. CONCLUSION NemR controls expression of genes encoding electrophile detoxification enzymes, which increase bleach resistance. SIGNIFICANCE We demonstrate a bleach-sensing bacterial response system and a new mechanism contributing to bacterial bleach survival. Hypochlorous acid (HOCl), the active component of household bleach, also functions as a powerful antimicrobial during the innate immune response. Despite its widespread use, surprisingly little is known about how cells sense or respond to HOCl. We now demonstrate that Escherichia coli NemR is a redox-regulated transcriptional repressor, which uses the oxidation status of HOCl-sensitive cysteine residues to respond to bleach and related reactive chlorine species. NemR controls bleach-mediated expression of two enzymes required for detoxification of reactive electrophiles: glyoxalase I and N-ethylmaleimide reductase. Both enzymes contribute to bacterial bleach survival. These results provide evidence that bleach resistance relies on the capacity of organisms to specifically sense reactive chlorine species and respond with the up-regulation of enzymes dedicated to detoxification of methylglyoxal and other reactive electrophiles.
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Affiliation(s)
- Michael J Gray
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
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