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Addison JB, Koontz C, Fugett JH, Creighton CJ, Chen D, Farrugia MK, Padon RR, Voronkova MA, McLaughlin SL, Livengood RH, Lin CC, Ruppert JM, Pugacheva EN, Ivanov AV. KAP1 promotes proliferation and metastatic progression of breast cancer cells. Cancer Res 2014; 75:344-55. [PMID: 25421577 DOI: 10.1158/0008-5472.can-14-1561] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
KAP1 (TRIM28) is a transcriptional regulator in embryonic development that controls stem cell self-renewal, chromatin organization, and the DNA damage response, acting as an essential corepressor for KRAB family zinc finger proteins (KRAB-ZNF). To gain insight into the function of this large gene family, we developed an antibody that recognizes the conserved zinc fingers linker region (ZnFL) in multiple KRAB-ZNF. Here, we report that the expression of many KRAB-ZNF along with active SUMOlyated KAP1 is elevated widely in human breast cancers. KAP1 silencing in breast cancer cells reduced proliferation and inhibited the growth and metastasis of tumor xenografts. Conversely, KAP1 overexpression stimulated cell proliferation and tumor growth. In cells where KAP1 was silenced, we identified multiple downregulated genes linked to tumor progression and metastasis, including EREG/epiregulin, PTGS2/COX2, MMP1, MMP2, and CD44, along with downregulation of multiple KRAB-ZNF proteins. KAP1-dependent stabilization of KRAB-ZNF required direct interactions with KAP1. Together, our results show that KAP1-mediated stimulation of multiple KRAB-ZNF contributes to the growth and metastasis of breast cancer.
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Affiliation(s)
- Joseph B Addison
- Mary Babb Randolph Cancer Center and Department of Biochemistry, West Virginia University, Morgantown, West Virginia
| | - Colton Koontz
- Mary Babb Randolph Cancer Center and Department of Biochemistry, West Virginia University, Morgantown, West Virginia
| | - James H Fugett
- Mary Babb Randolph Cancer Center and Department of Biochemistry, West Virginia University, Morgantown, West Virginia
| | - Chad J Creighton
- Department of Medicine and Dan L. Duncan Cancer Center Division of Biostatistics, Baylor College of Medicine, Houston, Texas
| | - Dongquan Chen
- Division of Preventive Medicine and UAB Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, Alabama
| | - Mark K Farrugia
- Mary Babb Randolph Cancer Center and Department of Biochemistry, West Virginia University, Morgantown, West Virginia
| | - Renata R Padon
- Mary Babb Randolph Cancer Center and Department of Biochemistry, West Virginia University, Morgantown, West Virginia
| | - Maria A Voronkova
- Mary Babb Randolph Cancer Center and Department of Biochemistry, West Virginia University, Morgantown, West Virginia
| | - Sarah L McLaughlin
- Mary Babb Randolph Cancer Center and Department of Biochemistry, West Virginia University, Morgantown, West Virginia
| | - Ryan H Livengood
- Department of Pathology, West Virginia University, Morgantown, West Virginia
| | - Chen-Chung Lin
- Mary Babb Randolph Cancer Center and Department of Biochemistry, West Virginia University, Morgantown, West Virginia
| | - J Michael Ruppert
- Mary Babb Randolph Cancer Center and Department of Biochemistry, West Virginia University, Morgantown, West Virginia
| | - Elena N Pugacheva
- Mary Babb Randolph Cancer Center and Department of Biochemistry, West Virginia University, Morgantown, West Virginia
| | - Alexey V Ivanov
- Mary Babb Randolph Cancer Center and Department of Biochemistry, West Virginia University, Morgantown, West Virginia.
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2
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Lupo A, Cesaro E, Montano G, Zurlo D, Izzo P, Costanzo P. KRAB-Zinc Finger Proteins: A Repressor Family Displaying Multiple Biological Functions. Curr Genomics 2013; 14:268-78. [PMID: 24294107 PMCID: PMC3731817 DOI: 10.2174/13892029113149990002] [Citation(s) in RCA: 168] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Revised: 05/15/2013] [Accepted: 05/16/2013] [Indexed: 12/23/2022] Open
Abstract
Zinc finger proteins containing the Kruppel associated box (KRAB-ZFPs) constitute the largest individual family of transcriptional repressors encoded by the genomes of higher organisms. KRAB domain, positioned at the NH2 terminus of the KRAB-ZFPs, interacts with a scaffold protein, KAP-1, which is able to recruit various transcriptional factors causing repression of genes to which KRAB ZFPs bind. The relevance of such repression is reflected in the large number of the KRAB zinc finger protein genes in the human genome. However, in spite of their numerical abundance little is currently known about the gene targets and the physiological functions of KRAB- ZFPs. However, emerging evidence links the transcriptional repression mediated by the KRAB-ZFPs to cell proliferation, differentiation, apoptosis and cancer. Moreover, the fact that KRAB containing proteins are vertebrate-specific suggests that they have evolved recently, and that their key roles lie in some aspects of vertebrate development. In this review, we will briefly discuss some regulatory functions of the KRAB-ZFPs in different physiological and pathological states, thus contributing to better understand their biological roles.
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Affiliation(s)
- Angelo Lupo
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università di Napoli "Federico II", Via S. Pansini 5, 80131 Napoli, Italy; ; Dipartimento di Scienze per la Biologia, la Geologia e l'Ambiente, Facoltà di Scienze, Università del Sannio, Via Port'Arsa 11, 82100 Benevento, Italy
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3
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Fang M, Jacob R, McDougal O, Oxford JT. Minor fibrillar collagens, variable regions alternative splicing, intrinsic disorder, and tyrosine sulfation. Protein Cell 2012; 3:419-33. [PMID: 22752873 DOI: 10.1007/s13238-012-2917-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2011] [Accepted: 02/07/2012] [Indexed: 12/25/2022] Open
Abstract
Minor fibrillar collagen types V and XI, are those less abundant than the fibrillar collagen types I, II and III. The alpha chains share a high degree of similarity with respect to protein sequence in all domains except the variable region. Genomic variation and, in some cases, extensive alternative splicing contribute to the unique sequence characteristics of the variable region. While unique expression patterns in tissues exist, the functions and biological relevance of the variable regions have not been elucidated. In this review, we summarize the existing knowledge about expression patterns and biological functions of the collagen types V and XI alpha chains. Analysis of biochemical similarities among the peptides encoded by each exon of the variable region suggests the potential for a shared function. The alternative splicing, conservation of biochemical characteristics in light of low sequence conservation, and evidence for intrinsic disorder, suggest modulation of binding events between the surface of collagen fibrils and surrounding extracellular molecules as a shared function.
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Affiliation(s)
- Ming Fang
- Department of Biological Sciences, Boise State University, Boise, ID 83725, USA
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4
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Swindell WR, Johnston A, Sun L, Xing X, Fisher GJ, Bulyk ML, Elder JT, Gudjonsson JE. Meta-profiles of gene expression during aging: limited similarities between mouse and human and an unexpectedly decreased inflammatory signature. PLoS One 2012; 7:e33204. [PMID: 22413003 PMCID: PMC3296693 DOI: 10.1371/journal.pone.0033204] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2011] [Accepted: 02/13/2012] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Skin aging is associated with intrinsic processes that compromise the structure of the extracellular matrix while promoting loss of functional and regenerative capacity. These processes are accompanied by a large-scale shift in gene expression, but underlying mechanisms are not understood and conservation of these mechanisms between humans and mice is uncertain. RESULTS We used genome-wide expression profiling to investigate the aging skin transcriptome. In humans, age-related shifts in gene expression were sex-specific. In females, aging increased expression of transcripts associated with T-cells, B-cells and dendritic cells, and decreased expression of genes in regions with elevated Zeb1, AP-2 and YY1 motif density. In males, however, these effects were contrasting or absent. When age-associated gene expression patterns in human skin were compared to those in tail skin from CB6F1 mice, overall human-mouse correspondence was weak. Moreover, inflammatory gene expression patterns were not induced with aging of mouse tail skin, and well-known aging biomarkers were in fact decreased (e.g., Clec7a, Lyz1 and Lyz2). These unexpected patterns and weak human-mouse correspondence may be due to decreased abundance of antigen presenting cells in mouse tail skin with age. CONCLUSIONS Aging is generally associated with a pro-inflammatory state, but we have identified an exception to this pattern with aging of CB6F1 mouse tail skin. Aging therefore does not uniformly heighten inflammatory status across all mouse tissues. Furthermore, we identified both intercellular and intracellular mechanisms of transcriptome aging, including those that are sex- and species-specific.
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Affiliation(s)
- William R Swindell
- Department of Genetics, Harvard Medical School, Boston, Massachusetts, United States of America.
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5
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Frietze S, Lan X, Jin VX, Farnham PJ. Genomic targets of the KRAB and SCAN domain-containing zinc finger protein 263. J Biol Chem 2009; 285:1393-403. [PMID: 19887448 DOI: 10.1074/jbc.m109.063032] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Half of all human transcription factors use C2H2 zinc finger domains to specify site-specific DNA binding and yet very little is known about their role in gene regulation. Based on in vitro studies, a zinc finger code has been developed that predicts a binding motif for a particular zinc finger factor (ZNF). However, very few studies have performed genome-wide analyses of ZNF binding patterns, and thus, it is not clear if the binding code developed in vitro will be useful for identifying target genes of a particular ZNF. We performed genome-wide ChIP-seq for ZNF263, a C2H2 ZNF that contains 9 finger domains, a KRAB repression domain, and a SCAN domain and identified more than 5000 binding sites in K562 cells. Our results suggest that ZNF263 binds to a 24-nt site that differs from the motif predicted by the zinc finger code in several positions. Interestingly, many of the ZNF263 binding sites are located within the transcribed region of the target gene. Although ZNFs containing a KRAB domain are thought to function mainly as transcriptional repressors, many of the ZNF263 target genes are expressed at high levels. To address the biological role of ZNF263, we identified genes whose expression was altered by treatment of cells with ZNF263-specific small interfering RNAs. Our results suggest that ZNF263 can have both positive and negative effects on transcriptional regulation of its target genes.
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Affiliation(s)
- Seth Frietze
- Department of Pharmacology and the Genome Center, University of California, Davis, California 95616, USA
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6
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Briers S, Crawford C, Bickmore WA, Sutherland HG. KRAB zinc-finger proteins localise to novel KAP1-containing foci that are adjacent to PML nuclear bodies. J Cell Sci 2009; 122:937-46. [PMID: 19258395 DOI: 10.1242/jcs.034793] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The KRAB-zinc finger proteins (KRAB-ZFPs) represent a very large, but poorly understood, family of transcriptional regulators in mammals. They are thought to repress transcription via their interaction with KRAB-associated protein 1 (KAP1), which then assembles a complex of chromatin modifiers to lay down histone marks that are associated with inactive chromatin. Studies of KRAB-ZFP/KAP1-mediated gene silencing, using reporter constructs and ectopically expressed proteins, have shown colocalisation of both KAP1 and repressed reporter target genes to domains of constitutive heterochromatin in the nucleus. However, we show here that although KAP1 does indeed become recruited to pericentric heterochromatin during differentiation of mouse embryonic stem (ES) cells, endogenous KRAB-ZFPs do not. Rather, KRAB-ZFPs and KAP1 relocalise to novel nucleoplasmic foci that we have termed KRAB- and KAP1-associated (KAKA) foci. HP1s can also concentrate in these foci and there is a close spatial relationship between KAKA nuclear foci and PML nuclear bodies. Finally, we reveal differential requirements for the recruitment of KAP1 to pericentric heterochromatin and KAKA foci, and suggest that KAKA foci may contain sumoylated KAP1 - the form of the protein that is active in transcriptional repression.
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Affiliation(s)
- Stephanie Briers
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, UK
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7
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Goto T, Matsui Y, Fernandes RJ, Hanson DA, Kubo T, Yukata K, Michigami T, Komori T, Fujita T, Yang L, Eyre DR, Yasui N. Sp1 family of transcription factors regulates the human alpha2 (XI) collagen gene (COL11A2) in Saos-2 osteoblastic cells. J Bone Miner Res 2006; 21:661-73. [PMID: 16734381 DOI: 10.1359/jbmr.020605] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
UNLABELLED Genes encoding type XI collagen, normally associated with chondrogenesis, are also expressed by osteoblasts. By studying Saos-2 cells, we showed that the transcription factors, Sp1, Sp3, and Sp7 (Osterix), regulate COL11A2 expression through its proximal promoter. The findings indicate both ubiquitous and osteoblast-specific mechanisms of collagen gene regulation. INTRODUCTION Type XI collagen is essential for skeletal morphogenesis. Collagen XI gene regulation has been studied in chondrocytes but not in osteoblasts. MATERIALS AND METHODS We cultured Saos-2 cells, a human osteosarcoma-derived line of osteoblasts, and analyzed them for alpha2(XI) protein and COL11A2 regulatory mechanisms. RESULTS AND CONCLUSIONS Although types I and V were the dominant collagens deposited by Saos-2 cells, they expressed COL11A2 mRNA, and alpha2(XI) chains were present in the extracellular matrix. The COL11A2 promoter region (from -149 to -40) containing three Sp1 binding sites was required for promoter activity in transient transfection assays. All three Sp1 sites were critical for binding by nuclear proteins in electrophoretic mobility shift assays. Further analysis using consensus oligonucleotides and specific antibodies as well as chromatin immunoprecipitation assay implicated Sp1 and Sp3 in binding to this promoter region. Overexpressing Sp1 or Sp3 significantly increased COL11A2 promoter activity and endogenous COL11A2 gene expression, an effect that was suppressed by the Sp1-binding inhibitor mithramycin A. Further experiments showed that Sp1, Sp3, CREB-binding protein (CBP), p300, and histone deacetylase (HDAC) were physically associated and HDAC inhibitors (trichostatin A or NaB) upregulated COL11A2 promoter activity and endogenous gene expression. Another Sp1 family member, Sp7 (Osterix), was expressed in Saos-2 cells, but not in chondrocytes, and was shown by chromatin immunoprecipitation to occupy the COL11A2 promoter. Overexpressing Sp7 increased COL11A2 promoter activity and endogenous gene expression, an effect also blocked by mithramycin A. Using siRNA to knockdown Sp1, Sp3, or Sp7, it was shown that depression of any of them decreased COL11A2 promoter activity and endogenous gene expression. Finally, primary cultures of osteoblasts expressed COL11A2 and Sp7, upregulated COL11A2 promoter activity and endogenous gene expression when Sp1, Sp3, or Sp7 were overexpressed, and downregulated them when Sp1, Sp3, or Sp7 were selectively depressed. The results establish that Sp1 proteins regulate COL11A2 transcription by binding to its proximal promoter and directly interacting with CBP, p300, and HDAC.
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Affiliation(s)
- Tomohiro Goto
- Department of Orthopaedics, Institute of Health Biosciences, The University of Tokushima Graduate School, Japan
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8
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Huntley S, Baggott DM, Hamilton AT, Tran-Gyamfi M, Yang S, Kim J, Gordon L, Branscomb E, Stubbs L. A comprehensive catalog of human KRAB-associated zinc finger genes: insights into the evolutionary history of a large family of transcriptional repressors. Genome Res 2006; 16:669-77. [PMID: 16606702 PMCID: PMC1457042 DOI: 10.1101/gr.4842106] [Citation(s) in RCA: 241] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Krüppel-type zinc finger (ZNF) motifs are prevalent components of transcription factor proteins in all eukaryotes. KRAB-ZNF proteins, in which a potent repressor domain is attached to a tandem array of DNA-binding zinc-finger motifs, are specific to tetrapod vertebrates and represent the largest class of ZNF proteins in mammals. To define the full repertoire of human KRAB-ZNF proteins, we searched the genome sequence for key motifs and then constructed and manually curated gene models incorporating those sequences. The resulting gene catalog contains 423 KRAB-ZNF protein-coding loci, yielding alternative transcripts that altogether predict at least 742 structurally distinct proteins. Active rounds of segmental duplication, involving single genes or larger regions and including both tandem and distributed duplication events, have driven the expansion of this mammalian gene family. Comparisons between the human genes and ZNF loci mined from the draft mouse, dog, and chimpanzee genomes not only identified 103 KRAB-ZNF genes that are conserved in mammals but also highlighted a substantial level of lineage-specific change; at least 136 KRAB-ZNF coding genes are primate specific, including many recent duplicates. KRAB-ZNF genes are widely expressed and clustered genes are typically not coregulated, indicating that paralogs have evolved to fill roles in many different biological processes. To facilitate further study, we have developed a Web-based public resource with access to gene models, sequences, and other data, including visualization tools to provide genomic context and interaction with other public data sets.
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Affiliation(s)
| | | | | | | | | | | | | | - Elbert Branscomb
- Microbial Systems Divisions, Biosciences, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - Lisa Stubbs
- Genome Biology
- Corresponding author.E-mail ; fax (925) 422-2099
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9
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Edelstein LC, Collins T. The SCAN domain family of zinc finger transcription factors. Gene 2005; 359:1-17. [PMID: 16139965 DOI: 10.1016/j.gene.2005.06.022] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2005] [Revised: 05/26/2005] [Accepted: 06/03/2005] [Indexed: 12/29/2022]
Abstract
Zinc finger transcription factor genes represent a significant portion of the genes in the vertebrate genome. Some Cys2His2 type zinc fingers are associated with conserved protein domains that help to define these regulators. A novel domain of this type, the SCAN domain, is a highly conserved 84-residue motif that is found near the N-terminus of a subfamily of C2H2 zinc finger proteins. The SCAN domain, which is also known as the leucine rich region, functions as a protein interaction domain, mediating self-association or selective association with other proteins. Here we define the mouse SCAN domain and annotate the mouse SCAN family members. In addition to a single SCAN domain, some of the members of the mouse SCAN family members have a conserved N-terminal motif, a KRAB domain, SANT domains and a variable number of C2H2 type zinc fingers (3-14). The genes encoding mouse SCAN domains are clustered, often in tandem arrays, and are capable of generating isoforms that may affect the function of family members. Although the function of most of the family members is not known, an overview of selected members of this group of transcription factors suggests that some of the mouse SCAN domain family members play roles in cell survival and differentiation.
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Affiliation(s)
- Leonard C Edelstein
- Department of Pathology, Children's Hospital Boston and Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
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10
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Jing Z, Liu Y, Dong M, Hu S, Huang S. Identification of the DNA binding element of the human ZNF333 protein. BMB Rep 2005; 37:663-70. [PMID: 15607024 DOI: 10.5483/bmbrep.2004.37.6.663] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
ZNF 333 is a new and sole gene containing two KRAB domains which has been identified currently. It is a member of subfamilies of zinc finger gene complex which had been localized on chromosome 19p13.1. The ZNF333 gene mainly encodes a 75.5 kDa protein which contains 10 zinc finger domains. Using the methods of random oligonucleotide selection assay, electromobility gel shift assay and luciferase activity assay, we found that ZNF333 recognized the specific DNA core binding sequence ATAAT. Moreover, these data indicated that the KRAB domain of ZNF333 really has the ability of transcriptional repression.
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Affiliation(s)
- Zhe Jing
- Department of Medical Genetics, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China
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11
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Abstract
Zinc (Zn) deficiency, a frequent condition in human populations, induces oxidative stress and subsequently activates/inhibits oxidant-sensitive transcription factors that can affect cell function, proliferation and survival leading to disease. Zn deficiency-triggered oxidative stress could affect cell signaling, including: (1) transcription factors containing Zn finger motifs, and (2) other oxidant-sensitive transcription factors (NF-kappaB and AP-1). The Zn finger motif in the Zn finger transcription factors is mainly a DNA binding domain. Cysteine residues coordinate the Zn ion folding structural domains that participate in intermolecular interactions. Oxidative stress can impair the DNA-binding activity of Zn finger transcription factor, by oxidizing the cysteine residues and therefore altering the secondary structure of the protein. AP-1 is generally activated in Zn deficiency that can occur secondary to an increase in cellular H(2)O(2), followed by activation of MAPKs p38 and JNK. The role of AP-1 in Zn deficiency-associated pathology remains to be established. The cytosolic steps of the NF-kappaB cascade are activated by oxidants in Zn deficiency. However, an impaired nuclear transport of the active transcription factor leads to a low expression of NF-kappaB-dependent genes that could be involved in multiple aspects of Zn deficiency associated pathology. In summary, Zn deficiency induces oxidative stress that can both, lead to tissue oxidative damage and/or to the modulation of select signaling cascades. Their role in the pathology of Zn deficiency remains to be defined.
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Affiliation(s)
- Patricia I Oteiza
- Department of Nutrition, University of California, Davis, CA 95616, USA.
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12
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Krebs CJ, Larkins LK, Khan SM, Robins DM. Expansion and diversification of KRAB zinc-finger genes within a cluster including Regulator of sex-limitation 1 and 2. Genomics 2005; 85:752-61. [PMID: 15885501 DOI: 10.1016/j.ygeno.2005.03.004] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2005] [Revised: 03/07/2005] [Accepted: 03/08/2005] [Indexed: 12/22/2022]
Abstract
The genomic locus on mouse chromosome 13 called Regulator of sex-limitation (Rsl) accentuates sex differences in hepatic gene expression. Females homozygous for variant rsl alleles express some otherwise male-specific liver proteins, such as sex-limited protein (Slp), major urinary proteins (MUPs), and members of the cytochrome P450 (cyp) 2d subfamily. We recently identified mutations in two genes, Rsl1 and Rsl2, accounting for the rsl phenotype. These genes encode KRAB zinc-finger proteins (KRAB-ZFPs) and are embedded within a cluster of over 20 similar genes. Mammalian genomes contain over 200 KRAB-ZFP genes, which act biochemically to repress transcription, but the Rsl genes are the first to have their biological functions elucidated. Here we compare Rsl1 and Rsl2 with their neighboring genes, tracing a series of duplication, inversion, and gene conversion events that have created subfamilies within the locus. Polymorphisms among inbred mouse strains and feral species suggest that mutations responsible for the rsl phenotype arose during the creation of inbred strains. Comparisons among mouse, rat, and human sequences show that the Rsl genes, like members of certain other multigene families, have diversified in a species-specific manner. The targets of Rsl regulation also vary between species, occurring in gene families with functions in steroid and xenobiotic metabolism (Cyp2d), reproduction (MUPs), and immunity (Slp). This suggests that the Rsl locus in mouse, and comparable KRAB-ZFP genes in other mammals, may play a role in speciation via modulation of expression of genes influencing reproductive fitness or behavior.
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Affiliation(s)
- Christopher J Krebs
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI 48109-0618, USA
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13
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Abstract
Chondrogenesis is an essential process in vertebrates. It leads to the formation of cartilage growth plates, which drive body growth and have primary roles in endochondral ossification. It also leads to the formation of permanent cartilaginous tissues that provide major structural support in the articular joints and respiratory and auditory tracts throughout life. Defects in chondrogenesis cause chondrodysostoses and chondrodysplasias. These skeletal malformation diseases account for a significant proportion of birth defects in humans and can dramatically affect a person's expectancy and quality of life. Chondrogenesis occurs when pluripotent mesenchymal cells commit to the chondrocyte lineage, and through a series of differentiation steps build and eventually remodel cartilage. This review summarizes and discusses our current knowledge and lack of knowledge about the chondrocyte differentiation pathway, from mesenchymal cells to growth plate and articular chondrocytes, with a main focus on how it is controlled by tissue patterning and cell differentiation transcription factors, such as, but not limited to, Pax1 and Pax9, Nkx3.1 and Nkx3.2, Sox9, Sox5 and Sox6, Runx2 and Runx3, and c-Maf.
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Affiliation(s)
- Véronique Lefebvre
- Department of Biomedical Engineering and Orthopaedic Research Center, Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA.
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14
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Hamilton AT, Huntley S, Kim J, Branscomb E, Stubbs L. Lineage-specific expansion of KRAB zinc-finger transcription factor genes: implications for the evolution of vertebrate regulatory networks. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 2004; 68:131-40. [PMID: 15338611 DOI: 10.1101/sqb.2003.68.131] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- A T Hamilton
- Genome Biology Division, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
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Oh HJ, Li Y, Lau YFC. Sry associates with the heterochromatin protein 1 complex by interacting with a KRAB domain protein. Biol Reprod 2004; 72:407-15. [PMID: 15469996 DOI: 10.1095/biolreprod.104.034447] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
In mammals, the SRY/Sry gene on the Y chromosome is necessary and sufficient for a bipotential gonad to develop into a testis, regardless of its chromosomal sex. The SRY/Sry gene encodes a protein that belongs to a high-mobility-group (HMG) box protein family and that has been postulated to modulate the expression of genes necessary for male gonadal differentiation. Using a yeast two-hybrid screen, we identified a novel protein containing only a Krüppel-associated box (KRAB) domain, which is hereafter named KRAB-O (KRAB Only), as an SRY-interacting protein. The KRAB-O protein is encoded by an alternatively spliced transcript from the Zfp208 locus that also produces another transcript coding for a KRAB-zinc finger protein, ZFP208. The interaction of the mouse SRY with KRAB-O was further confirmed by glutathione S-transferase pull-down assay and coimmunoprecipitation in transfected COS7 cells. The KRAB-O interaction domain in both the human and mouse SRY was mapped to the bridge region outside the HMG box. Indirect immunofluorescence and confocal microscopy show that the mouse SRY colocalizes with KRAB-O in nuclear dots in transiently transfected COS7 cells and primary fetal mouse gonadal cells. Using similar approaches, we demonstrate that KRAB-O interacts directly with KAP1 (KRAB-associated protein 1), the obligatory corepressor for KRAB domain proteins. Furthermore, we show that the mouse SRY is associated indirectly with KAP1 and heterochromatin protein 1 (HP1) through its interaction with KRAB-O, suggesting that the mouse SRY could use the KRAB-KAP1-HP1 organized transcriptional regulatory complex to regulate its yet-to-be-identified downstream target genes.
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Affiliation(s)
- Hyun Ju Oh
- Division of Cell and Developmental Genetics, Department of Medicine, VA Medical Center, University of California, San Francisco, California 94121, USA
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16
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Abstract
Extracellular matrix metabolism plays a central role in development of skeletal tissues and in most orthopaedic diseases and trauma such as fracture or osteotomy repair, arthritis, cartilage repair, and congenital skeletal deformity. During development or disease, specific genes must be expressed in order to make or repair appropriate extracellular matrix. For example, specific gene expression patterns are characteristic of bone and cartilage. The precise expression pattern depends on a balance of positive and negative transcription factors, proteins that control the synthesis of mRNA from the specific gene. In cartilage, a number of studies indicate that Sox transcription factors are critical positive regulators in genes such as COL2A1, COL9A2, COL11A2, aggrecan, and CD-RAP. In addition, negative regulators are also essential to fine tune gene regulation in chondrocytes and to turn off gene expression in noncartilaginous tissues. Negative transcription factors in cartilage include partial differentialEF-1, snail/slug, CYRBP1, NT2, and C/EBP. Runx2 and osterix are critical transcription factors for osteogenesis but also have some influence on chondrogenesis. The availability of cis-regulatory sites in specific genes combined with the availability of transcription factors in the nucleus determines the level of gene expression.
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Affiliation(s)
- Ken Okazaki
- Department of Orthopaedic Surgery, Washington University School of Medicine at Barnes-Jewish Hospital, St. Louis, MO 63110, USA
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17
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Ponticos M, Partridge T, Black CM, Abraham DJ, Bou-Gharios G. Regulation of collagen type I in vascular smooth muscle cells by competition between Nkx2.5 and deltaEF1/ZEB1. Mol Cell Biol 2004; 24:6151-61. [PMID: 15226419 PMCID: PMC434261 DOI: 10.1128/mcb.24.14.6151-6161.2004] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
A major component of the vessel wall of large arteries and veins is the extracellular matrix (ECM), which consists of collagens, elastin, and proteoglycans. Collagen type I is one of the most abundant of the ECM proteins. We have previously shown that the pro-collagen type I alpha 2 gene contains an enhancer which confers tissue-specific expression in the majority of collagen-producing cells, including blood vessels. In this paper, we delineate a specific vascular smooth muscle cell (vSMC) element: a 100-bp sequence around -16.6 kb upstream of the transcription start site that regulates collagen expression exclusively in vSMCs. Furthermore, we show that the expression is activated through the binding of the homeodomain protein Nkx2.5, which is further potentiated in the presence of GATA6. In contrast, this element was repressed by the binding of the zinc-finger protein deltaEF1/ZEB1. We propose a model of regulation where the activating transcription factor Nkx2.5 and the repressor deltaEF1/ZEB1 compete for an overlapping DNA binding site. This element is important in understanding the molecular mechanisms of vessel remodeling and is a potential target for intervention in vascular diseases where there is excessive deposition of collagen in the vessel wall.
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Affiliation(s)
- Markella Ponticos
- Centre for Rheumatology, Department of Medicine, University College of London, United Kingdom
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18
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Abstract
Cellular and molecular processes that regulate the development of skeletal tissues resemble those required for regeneration. Given the prevalence of degenerative skeletal disorders in an increasingly aging population, the molecular mechanisms of skeletal development must be understood in detail if novel strategies are to be developed in regenerative medicine. Research in this area over the past decade has revealed that cell differentiation is largely controlled at the level of gene transcription, which in turn is regulated by transcription factors. Transcription factors usually recognize and bind to specific DNA sequences in the promoter of target genes via characteristic DNA-binding domains. Although the gene family containing C2H2 zinc fingers as DNA-binding motifs is the largest family of transciptional regulators, with several hundred individual members in mammals, only a small but increasing number of zinc finger genes have been implicated in bone, cartilage, or tooth development. These zinc finger proteins (ZFPs) contain multiple structural motifs that require zinc to maintain their structural integrity and function. Interestingly, zinc deficiency is known to result in skeletal growth retardation and has been identified as a risk factor in the pathogenesis of osteoporosis. This review attempts to summarize our current state of knowledge regarding the role of ZFPs in the molecular regulation of skeletogenesis.
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Issack PS, Liu CJ, Prazak L, Di Cesare PE. A silencer element in the cartilage oligomeric matrix protein gene regulates chondrocyte-specific expression. J Orthop Res 2004; 22:751-8. [PMID: 15183430 DOI: 10.1016/j.orthres.2003.12.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2003] [Accepted: 12/04/2003] [Indexed: 02/04/2023]
Abstract
The molecular mechanisms by which mesenchymal cells differentiate into chondrocytes are poorly understood. The cartilage oligomeric matrix protein gene (COMP) encodes a noncollagenous extracellular matrix protein whose expression pattern correlates with chondrocyte differentiation and arthritis. We have used the COMP promoter as a model to identify regulatory sequences necessary for chondrocyte-specific expression and to identify cell type-specific proteins that bind these sequences. We have previously cloned 1.9 kilobases of the 5(') flanking promoter sequence of the murine COMP gene and by deletion analysis have identified two spatially distant chondrocyte-specific regulatory regions. One element is situated proximally (-125 to -75), and a second region is located distally (-1925 to -592) relative to the transcription start site. In the present study, we performed a finer deletion analysis of the region of the COMP promoter from -1925 to -592 and identified a silencer region situated between -1775 and -1725. This silencer binds sequence-specific protein complexes; the intensity of these complexes is greater in two different fibroblast cell lines (NIH3T3 and 10T1/2) than in chondrocytic RCS cells. Competition experiments localized the binding site of these protein complexes from -1775 to -1746; deletion of this 30-bp site results in a selective increase in COMP promoter activity in fibroblasts. Four tandem repeats of this 30-bp site are sufficient to confer negative transcriptional regulation on a heterologous promoter (SV40) in NIH3T3 fibroblasts. These results suggest that negative regulation of transcription is an important mechanism for chondrocyte-specific expression of the COMP gene.
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Affiliation(s)
- Paul S Issack
- Department of Orthopaedic Surgery, Musculoskeletal Research Center, Hospital for Joint Diseases, NYU, 301 East 17th Street, New York, NY, USA
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20
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Waxman DJ, Celenza JL. Sexual dimorphism of hepatic gene expression: novel biological role of KRAB zinc finger repressors revealed. Genes Dev 2003; 17:2607-13. [PMID: 14597659 DOI: 10.1101/gad.1154603] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Affiliation(s)
- David J Waxman
- Division of Cell and Molecular Biology, Department of Biology, Boston University, Boston, Massachusetts 02215, USA
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21
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Watanabe K, Okada K. Two discrete cis elements control the Abaxial side-specific expression of the FILAMENTOUS FLOWER gene in Arabidopsis. THE PLANT CELL 2003; 15:2592-602. [PMID: 14555697 PMCID: PMC280563 DOI: 10.1105/tpc.015214] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2003] [Accepted: 08/27/2003] [Indexed: 05/19/2023]
Abstract
Our previous studies showed that a member of the YABBY gene family, FILAMENTOUS FLOWER (FIL), plays a role in specifying the abaxial side tissues in the development of lateral organs such as cotyledons, leaves, young flower buds, and flower organs. We examined the expression pattern of FIL and found a temporal change of expression domains in the developmental process of the floral meristem. We also examined the cis control regions by constructing a series of transgenic plants that carry green fluorescent protein under the control of the FIL promoter with several types of deletions, base changes, and tandem repeats and showed that the unique expression pattern is dependent on at least two cis-acting elements in the 5' regulatory region. One element proximal to the FIL gene would be responsible for the expression of both the abaxial and adaxial sides, and the other element of the 12-bp sequence would work to repress expression on the adaxial side.
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Affiliation(s)
- Keiro Watanabe
- Department of Botany, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
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22
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Krebs CJ, Larkins LK, Price R, Tullis KM, Miller RD, Robins DM. Regulator of sex-limitation (Rsl) encodes a pair of KRAB zinc-finger genes that control sexually dimorphic liver gene expression. Genes Dev 2003; 17:2664-74. [PMID: 14563677 PMCID: PMC280616 DOI: 10.1101/gad.1135703] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Sexually dimorphic expression of a broad array of liver proteins involved in reproduction and xenobiotic metabolism is induced at puberty by sex-specific growth hormone patterns. An additional control of sex-dependent gene expression is conferred by Regulator of sex-limitation (Rsl) alleles. In variant rsl mice, females inappropriately express the male Sex-limited protein, Slp. We recently showed that a panel of male-specific liver genes is repressed by Rsl, accentuating sex differences in a hormone-independent manner. Here we map rsl to a region on Chromosome 13 comprised exclusively of KRAB (Kruppel-associated box) zinc-finger protein (ZFP) genes. Among eight Rsl candidate (Rslcan) genes within the critical genetic interval, the recent duplicates Rslcan-4 and Rslcan-9 both harbor mutations in rsl mice (partial deletion and splice-site inactivation, respectively). Transgenesis with bacterial artificial chromosome (BAC) clones encompassing Rslcan-4 restores male-specific MUP (major urinary protein) expression to rsl mice, whereas a BAC containing Rslcan-9 rescues sex-specific expression of Slp and cytochrome P450 Cyp2d9. Thus, the Rslcan-4 and Rslcan-9 paralogs partitioned regulation of their target genes during evolution. This demonstrates the first biological role for a set of KRAB zinc-finger repressor proteins and reveals the molecular basis of a gene-silencing pathway critical for sexual dimorphism.
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Affiliation(s)
- Christopher J Krebs
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, Michigan 48109-0618, USA
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Matsuo N, Yu-Hua W, Sumiyoshi H, Sakata-Takatani K, Nagato H, Sakai K, Sakurai M, Yoshioka H. The transcription factor CCAAT-binding factor CBF/NF-Y regulates the proximal promoter activity in the human alpha 1(XI) collagen gene (COL11A1). J Biol Chem 2003; 278:32763-70. [PMID: 12805369 DOI: 10.1074/jbc.m305599200] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We have characterized the proximal promoter region of the human COL11A1 gene. Transient transfection assays indicate that the segment from -199 to +1 is necessary for the activation of basal transcription. Electrophoretic mobility shift assays (EMSAs) demonstrated that the ATTGG sequence, within the -147 to -121 fragment, is critical to bind nuclear proteins in the proximal COL11A1 promoter. We demonstrated that the CCAAT binding factor (CBF/NF-Y) bound to this region using an interference assay with consensus oligonucleotides and a supershift assay with specific antibodies in an EMSA. In a chromatin immunoprecipitation assay and EMSA using DNA-affinity-purified proteins, CBF/NF-Y proteins directly bound this region in vitro and in vivo. We also showed that four tandem copies of the CBF/NF-Y-binding fragment produced higher transcriptional activity than one or two copies, whereas the absence of a CBF/NF-Y-binding fragment suppressed the COL11A1 promoter activity. Furthermore, overexpression of a dominant-negative CBF-B/NF-YA subunit significantly inhibited promoter activity in both transient and stable cells. These results indicate that the CBF/NF-Y proteins regulate the transcription of COL11A1 by directly binding to the ATTGG sequence in the proximal promoter region.
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Affiliation(s)
- Noritaka Matsuo
- Department of Anatomy, Biology, and Medicine, Oita Medical University, Hasama-machi, Oita 879-5593, Japan
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Ayyanathan K, Lechner MS, Bell P, Maul GG, Schultz DC, Yamada Y, Tanaka K, Torigoe K, Rauscher FJ. Regulated recruitment of HP1 to a euchromatic gene induces mitotically heritable, epigenetic gene silencing: a mammalian cell culture model of gene variegation. Genes Dev 2003; 17:1855-69. [PMID: 12869583 PMCID: PMC196232 DOI: 10.1101/gad.1102803] [Citation(s) in RCA: 288] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Heterochromatin protein 1 (HP1) is a key component of constitutive heterochromatin in Drosophila and is required for stable epigenetic gene silencing classically observed as position effect variegation. Less is known of the family of mammalian HP1 proteins, which may be euchromatic, targeted to expressed loci by repressor-corepressor complexes, and retained there by Lys 9-methylated histone H3 (H3-MeK9). To characterize the physical properties of euchromatic loci bound by HP1, we developed a strategy for regulated recruitment of HP1 to an expressed transgene in mammalian cells by using a synthetic, hormone-regulated KRAB repression domain. We show that its obligate corepressor, KAP1, can coordinate all the machinery required for stable gene silencing. In the presence of hormone, the transgene is rapidly silenced, spatially recruited to HP1-rich nuclear regions, assumes a compact chromatin structure, and is physically associated with KAP1, HP1, and the H3 Lys 9-specific methyltransferase, SETDB1, over a highly localized region centered around the promoter. Remarkably, silencing established by a short pulse of hormone is stably maintained for >50 population doublings in the absence of hormone in clonal-cell populations, and the silent transgenes in these clones show promoter hypermethylation. Thus, like variegation in Drosophila, recruitment of mammalian HP1 to a euchromatic promoter can establish a silenced state that is epigenetically heritable.
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Matsui Y, Chansky HA, Barahmand-Pour F, Zielinska-Kwiatkowska A, Tsumaki N, Myoui A, Yoshikawa H, Yang L, Eyre DR. COL11A2 collagen gene transcription is differentially regulated by EWS/ERG sarcoma fusion protein and wild-type ERG. J Biol Chem 2003; 278:11369-75. [PMID: 12554743 DOI: 10.1074/jbc.m300164200] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A specific t(21;22) chromosomal translocation creates the chimeric EWS/ERG gene in some cases of Ewing's sarcoma. In the resultant EWS/ERG fusion protein, the N-terminal part of the ETS family protein ERG is replaced by the N terminus of the RNA-binding protein EWS. We found that both the EWS/ERG and COL11A2 genes are expressed in the Ewing's sarcoma cell line, CADO-ES1. To investigate a potential role for EWS/ERG in COL11A2 gene expression, we characterized the COL11A2 promoter and tested the ability of wild-type ERG and EWS/ERG sarcoma fusion protein to transactivate COL11A2 promoter using a luciferase assay. We found that expression of EWS/ERG, but not wild-type ERG, transactivated the COL11A2 promoter and that this transactivation required not only the N-terminal region of EWS but also an intact DNA-binding domain from ERG. Electrophoretic mobility shift assay using COL11A2 promoter sequence showed involvement of EWS/ERG in the formation of DNA-protein complexes, and chromatin immunoprecipitation assay revealed direct interaction between COL11A2 promoter and EWS/ERG fusion protein in vivo. EWS/ERG, but not wild-type ERG, bound to RNA polymerase II. Treatment of cells with the histone deacetylase inhibitor trichostatin A enabled ERG to transactivate the COL11A2 promoter, therefore abolishing the differential effects of EWS/ERG and ERG. Taken together, these findings indicate that the COL11A2 gene is regulated both by potential ERG association with a histone deacetylase complex and by direct EWS/ERG recruitment of RNA polymerase II.
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Affiliation(s)
- Yoshito Matsui
- Department of Orthopedics and Sports Medicine, University of Washington School of Medicine, Seattle, Washington 98195-6500, USA
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26
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Yang JJ. A novel zinc finger protein, ZZaPK, interacts with ZAK and stimulates the ZAK-expressing cells re-entering the cell cycle. Biochem Biophys Res Commun 2003; 301:71-7. [PMID: 12535642 DOI: 10.1016/s0006-291x(02)02980-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
ZAK has been implicated in cell cycle arrest regulation through its function on decreasing cyclin E expression. To explore the mechanistic basis for this regulation, the yeast two-hybrid system was used with a novel Krüppel-type C2H2 zinc finger member cloned. This cloned cDNA encodes a novel protein with Krüppel-type zinc fingers designed as ZZaPK (zinc finger and ZAK associated protein with KRAB domain) and is widely expressed. ZZaPK, when it is expressed in cells, is growth promoted and might lead to increasing E2F expression and induce cyclin E/CDK2 activity, which counteracts the ZAK function. The model proposed here is that ZAK might play a role as an upstream signal to suppress the ZZaPK function and decrease E2F expression.
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Affiliation(s)
- Jaw-Ji Yang
- School of Dentistry, Chung-Shan Medical University, Taichung 402, Taiwan.
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