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He M, Han Z, Liu L, Zheng YG. Untersuchung der epigenetischen Funktionen von Lysin‐Acetyltransferasen mit Methoden der chemischen Biologie. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201704745] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Maomao He
- Department of Pharmaceutical and Biochemical Sciences and Department of Statistics University of Georgia Athens Georgia 30602 USA
| | - Zhen Han
- Department of Pharmaceutical and Biochemical Sciences and Department of Statistics University of Georgia Athens Georgia 30602 USA
| | - Liang Liu
- Department of Pharmaceutical and Biochemical Sciences and Department of Statistics University of Georgia Athens Georgia 30602 USA
| | - Y. George Zheng
- Department of Pharmaceutical and Biochemical Sciences and Department of Statistics University of Georgia Athens Georgia 30602 USA
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2
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He M, Han Z, Liu L, Zheng YG. Chemical Biology Approaches for Investigating the Functions of Lysine Acetyltransferases. Angew Chem Int Ed Engl 2017; 57:1162-1184. [PMID: 28786225 DOI: 10.1002/anie.201704745] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Indexed: 12/20/2022]
Abstract
The side-chain acetylation of lysine residues in histones and non-histone proteins catalyzed by lysine acetyltransferases (KATs) represents a widespread posttranslational modification (PTM) in the eukaryotic cells. Lysine acetylation plays regulatory roles in major cellular pathways inside and outside the nucleus. In particular, KAT-mediated histone acetylation has an effect on all DNA-templated epigenetic processes. Aberrant expression and activation of KATs are commonly observed in human diseases, especially cancer. In recent years, the study of KAT functions in biology and disease has greatly benefited from chemical biology tools and strategies. In this Review, we present the past and current accomplishments in the design of chemical biology approaches for the interrogation of KAT activity and function. These methods and probes are classified according to their mechanisms of action and respective applications, with both strengths and limitations discussed.
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Affiliation(s)
- Maomao He
- Department of Pharmaceutical and Biochemical Sciences and Department of Statistics, University of Georgia, Athens, Georgia, 30602 (U, SA
| | - Zhen Han
- Department of Pharmaceutical and Biochemical Sciences and Department of Statistics, University of Georgia, Athens, Georgia, 30602 (U, SA
| | - Liang Liu
- Department of Pharmaceutical and Biochemical Sciences and Department of Statistics, University of Georgia, Athens, Georgia, 30602 (U, SA
| | - Y George Zheng
- Department of Pharmaceutical and Biochemical Sciences and Department of Statistics, University of Georgia, Athens, Georgia, 30602 (U, SA
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3
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Ma H, Howitz KT, Horiuchi KY, Wang Y. Histone Methyltransferase Activity Assays. EPIGENETICS FOR DRUG DISCOVERY 2015. [DOI: 10.1039/9781782628484-00267] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Histone methyltransferases (HMTs) methylate either the lysine or arginine residues on histones and other proteins and play a crucial role in epigenetic regulation. Over 70 HMTs are encoded by the human genome, and many have been implicated in the aetiology of cancer, inflammatory diseases, neurodegenerative diseases and other conditions. There are currently about a dozen HMT activity assays available, and many of these assay formats are applicable to other epigenetic factors, such as histone acetyltransferases, histone deacetylases, and histone and DNA demethylases. Many factors need to be considered in selecting an HMT assay for drug discovery studies, including cost, adaptability to high-throughput screening, and rates of false positives and false negatives. This chapter describes the mechanisms of the major assay platforms available for HMT screening and profiling and presents the advantages and limitations associated with each.
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Affiliation(s)
- Haiching Ma
- Reaction Biology Corporation One Great Valley Parkway, Suite 2 Malvern PA 19355 USA
| | - Konrad T. Howitz
- Reaction Biology Corporation One Great Valley Parkway, Suite 2 Malvern PA 19355 USA
| | - Kurumi Y. Horiuchi
- Reaction Biology Corporation One Great Valley Parkway, Suite 2 Malvern PA 19355 USA
| | - Yuren Wang
- Reaction Biology Corporation One Great Valley Parkway, Suite 2 Malvern PA 19355 USA
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4
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Ung T, Mason JL, Robinson RG, Spais CM, Ator MA, Angeles TS. A Cellular Assay for Inhibitors of the Fatty Acid Biosynthetic Pathway Using Scintillating Microplates. Assay Drug Dev Technol 2015; 13:285-92. [PMID: 26125659 DOI: 10.1089/adt.2015.644] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
A simplified method for monitoring the incorporation of radiolabeled acetate into lipids in a cellular system is described. The assay eliminates the commonly employed labor-intensive organic extraction step by plating the cells in 96-well tissue culture-treated ScintiPlates(®) that enable direct measurement of radiolabeled cell membrane-embedded lipids. Since the scintillant is entrenched in the plates, radioactivity in close proximity to the scintillant is measured without the need for liquid scintillation cocktail. The utility of this method for evaluating inhibitors of the de novo fatty acid synthetic pathway is demonstrated here with fatty acid synthase (FASN). Due to the upregulation of FASN activity in many tumor types, development of inhibitors to block the FASN activity in cells shows promise as an attractive and tractable approach for therapeutic intervention.
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Affiliation(s)
- Thao Ung
- 1 Lead Discovery and Profiling, Teva Branded Pharmaceutical Products R&D, Inc. , West Chester, Pennsylvania
| | - Jennifer L Mason
- 1 Lead Discovery and Profiling, Teva Branded Pharmaceutical Products R&D, Inc. , West Chester, Pennsylvania
| | - Ron G Robinson
- 1 Lead Discovery and Profiling, Teva Branded Pharmaceutical Products R&D, Inc. , West Chester, Pennsylvania
| | - Chrysanthe M Spais
- 2 Global Bioassay and Technology, Teva Branded Pharmaceutical Products R&D, Inc. , West Chester, Pennsylvania
| | - Mark A Ator
- 1 Lead Discovery and Profiling, Teva Branded Pharmaceutical Products R&D, Inc. , West Chester, Pennsylvania
| | - Thelma S Angeles
- 1 Lead Discovery and Profiling, Teva Branded Pharmaceutical Products R&D, Inc. , West Chester, Pennsylvania
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5
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Ngo L, Wu J, Yang C, Zheng YG. Effective Quenchers Are Required to Eliminate the Interference of Substrate: Cofactor Binding in the HAT Scintillation Proximity Assay. Assay Drug Dev Technol 2015; 13:210-20. [PMID: 26065557 PMCID: PMC4490742 DOI: 10.1089/adt.2015.636] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Histone acetyltransferases (HATs) mediate the transfer of an acetyl group from the cofactor, acetyl-CoA, to the side chain amino group of specific lysines in diverse protein substrates, most notably nuclear histones. The deregulation of HATs is connected to a number of disease states. Reliable and rapid biochemical assays for HATs are critical for understanding biological functions of protein acetylation, as well as for screening small-molecule inhibitors of HAT enzymes. In this report, we present a scintillation proximity assay (SPA) for the measurement of HAT enzymatic activities. The acetyl donor was [(3)H]Ac-CoA, and a biotin-modified histone peptide served as the HAT substrate. After the HAT reaction, streptavidin-coated beads were added to induce proximity of acetylated substrate to the scintillant molecules. However, we observed strong nonspecific binding between the cofactor and the histone peptide substrates, which adversely complicated the SPA performance. To prevent this problem, a set of chemical agents were evaluated to eliminate the cofactor-substrate interaction, thus providing reliable SPA readings. With optimization, the SPA showed consistent and robust performance for HAT activity measurement and HAT inhibitor evaluation. Overall, this mix-and-measure assay does not require any washing procedure, can be utilized in the microplate format, and is well suited for high-throughput screening of HAT chemical modulators.
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Affiliation(s)
- Liza Ngo
- Department of Pharmaceutical and Biomedical Sciences, The University of Georgia , Athens, Georgia
| | - Jiang Wu
- Department of Pharmaceutical and Biomedical Sciences, The University of Georgia , Athens, Georgia
| | - Chao Yang
- Department of Pharmaceutical and Biomedical Sciences, The University of Georgia , Athens, Georgia
| | - Yujun George Zheng
- Department of Pharmaceutical and Biomedical Sciences, The University of Georgia , Athens, Georgia
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Dahlin JL, Nissink JWM, Strasser JM, Francis S, Higgins L, Zhou H, Zhang Z, Walters MA. PAINS in the assay: chemical mechanisms of assay interference and promiscuous enzymatic inhibition observed during a sulfhydryl-scavenging HTS. J Med Chem 2015; 58:2091-113. [PMID: 25634295 PMCID: PMC4360378 DOI: 10.1021/jm5019093] [Citation(s) in RCA: 244] [Impact Index Per Article: 27.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Significant resources in early drug discovery are spent unknowingly pursuing artifacts and promiscuous bioactive compounds, while understanding the chemical basis for these adverse behaviors often goes unexplored in pursuit of lead compounds. Nearly all the hits from our recent sulfhydryl-scavenging high-throughput screen (HTS) targeting the histone acetyltransferase Rtt109 were such compounds. Herein, we characterize the chemical basis for assay interference and promiscuous enzymatic inhibition for several prominent chemotypes identified by this HTS, including some pan-assay interference compounds (PAINS). Protein mass spectrometry and ALARM NMR confirmed these compounds react covalently with cysteines on multiple proteins. Unfortunately, compounds containing these chemotypes have been published as screening actives in reputable journals and even touted as chemical probes or preclinical candidates. Our detailed characterization and identification of such thiol-reactive chemotypes should accelerate triage of nuisance compounds, guide screening library design, and prevent follow-up on undesirable chemical matter.
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Affiliation(s)
- Jayme L Dahlin
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine , Rochester, Minnesota 55905, United States
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Kuo YM, Henry RA, Andrews AJ. A quantitative multiplexed mass spectrometry assay for studying the kinetic of residue-specific histone acetylation. Methods 2014; 70:127-33. [PMID: 25123533 PMCID: PMC4477693 DOI: 10.1016/j.ymeth.2014.08.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2014] [Revised: 07/16/2014] [Accepted: 08/04/2014] [Indexed: 01/14/2023] Open
Abstract
Histone acetylation is involved in gene regulation and, most importantly, aberrant regulation of histone acetylation is correlated with major human diseases. Although many lysine acetyltransferases (KATs) have been characterized as being capable of acetylating multiple lysine residues on histones, how different factors such as enzyme complexes or external stimuli (e.g. KAT activators or inhibitors) alter KAT specificity remains elusive. In order to comprehensively understand how the homeostasis of histone acetylation is maintained, a method that can quantitate acetylation levels of individual lysines on histones is needed. Here we demonstrate that our mass spectrometry (MS)-based method accomplishes this goal. In addition, the high throughput, high sensitivity, and high dynamic range of this method allows for effectively and accurately studying steady-state kinetics. Based on the kinetic parameters from in vitro enzymatic assays, we can determine the specificity and selectivity of a KAT and use this information to understand what factors influence histone acetylation. These approaches can be used to study the enzymatic mechanisms of histone acetylation as well as be adapted to other histone modifications. Understanding the post-translational modification of individual residues within the histones will provide a better picture of chromatin regulation in the cell.
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Affiliation(s)
- Yin-Ming Kuo
- Department of Cancer Biology, Fox Chase Cancer Center, Philadelphia, PA 19111, USA
| | - Ryan A Henry
- Department of Cancer Biology, Fox Chase Cancer Center, Philadelphia, PA 19111, USA
| | - Andrew J Andrews
- Department of Cancer Biology, Fox Chase Cancer Center, Philadelphia, PA 19111, USA.
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8
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Dahlin JL, Sinville R, Solberg J, Zhou H, Han J, Francis S, Strasser JM, John K, Hook DJ, Walters MA, Zhang Z. A cell-free fluorometric high-throughput screen for inhibitors of Rtt109-catalyzed histone acetylation. PLoS One 2013; 8:e78877. [PMID: 24260132 PMCID: PMC3832525 DOI: 10.1371/journal.pone.0078877] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2013] [Accepted: 09/17/2013] [Indexed: 11/19/2022] Open
Abstract
The lysine acetyltransferase (KAT) Rtt109 forms a complex with Vps75 and catalyzes the acetylation of histone H3 lysine 56 (H3K56ac) in the Asf1-H3-H4 complex. Rtt109 and H3K56ac are vital for replication-coupled nucleosome assembly and genotoxic resistance in yeast and pathogenic fungal species such as Candida albicans. Remarkably, sequence homologs of Rtt109 are absent in humans. Therefore, inhibitors of Rtt109 are hypothesized as potential and minimally toxic antifungal agents. Herein, we report the development and optimization of a cell-free fluorometric high-throughput screen (HTS) for small-molecule inhibitors of Rtt109-catalyzed histone acetylation. The KAT component of the assay consists of the yeast Rtt109-Vps75 complex, while the histone substrate complex consists of full-length Drosophila histone H3-H4 bound to yeast Asf1. Duplicated assay runs of the LOPAC demonstrated day-to-day and plate-to-plate reproducibility. Approximately 225,000 compounds were assayed in a 384-well plate format with an average Z' factor of 0.71. Based on a 3σ cut-off criterion, 1,587 actives (0.7%) were identified in the primary screen. The assay method is capable of identifying previously reported KAT inhibitors such as garcinol. We also observed several prominent active classes of pan-assay interference compounds such as Mannich bases, catechols and p-hydroxyarylsulfonamides. The majority of the primary active compounds showed assay signal interference, though most assay artifacts can be efficiently removed by a series of straightforward counter-screens and orthogonal assays. Post-HTS triage demonstrated a comparatively small number of confirmed actives with IC50 values in the low micromolar range. This assay, which utilizes five label-free proteins involved in H3K56 acetylation in vivo, can in principle identify compounds that inhibit Rtt109-catalyzed H3K56 acetylation via different mechanisms. Compounds discovered via this assay or adaptations thereof could serve as chemical probes or leads for a new class of antifungals targeting an epigenetic enzyme.
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Affiliation(s)
- Jayme L. Dahlin
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine, Rochester, Minnesota, United States of America
- Medical Scientist Training Program, Mayo Clinic College of Medicine, Rochester, Minnesota, United States of America
| | - Rondedrick Sinville
- Institute for Therapeutics Discovery & Development, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Jonathan Solberg
- Institute for Therapeutics Discovery & Development, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Hui Zhou
- Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Rochester, Minnesota, United States of America
| | - Junhong Han
- Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Rochester, Minnesota, United States of America
| | - Subhashree Francis
- Institute for Therapeutics Discovery & Development, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Jessica M. Strasser
- Institute for Therapeutics Discovery & Development, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Kristen John
- Institute for Therapeutics Discovery & Development, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Derek J. Hook
- Institute for Therapeutics Discovery & Development, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Michael A. Walters
- Institute for Therapeutics Discovery & Development, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Zhiguo Zhang
- Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Rochester, Minnesota, United States of America
- * E-mail:
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9
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Gao T, Yang C, Zheng YG. Comparative studies of thiol-sensitive fluorogenic probes for HAT assays. Anal Bioanal Chem 2012; 405:1361-71. [PMID: 23138472 DOI: 10.1007/s00216-012-6522-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Revised: 10/18/2012] [Accepted: 10/23/2012] [Indexed: 01/15/2023]
Abstract
Histone acetyltransferases (HATs) catalyze the acetylation of specific lysine residues in histone and nonhistone proteins. Recent studies showed that acetylation is widely distributed among cellular proteins, suggestive of diverse functions of HATs in cellular pathways. Nevertheless, currently available assays for HAT activity study are still quite limited. Here, we evaluated a series of thiol-sensitive fluorogenic compounds for the detection of the enzymatic activities of different HAT proteins. Upon conjugation to the thiol group of HSCoA, these molecules gain enhanced quantum yields and strong fluorescence, permitting facile quantitation of HAT activities. We investigated and compared the assay performances of these fluorogenic compounds for their capability as HAT activity reporters, including kinetics of reaction with HSCoA, influence on HAT activity, and fluorescence amplification factors. Our data suggest that CPM and coumarin maleic acid ester are excellent HAT probes owing to their fast reaction kinetics and dramatic fluorescence enhancement during the HAT reaction. Further, the microtiter plate measurements show that this fluorescent approach is robust and well suited for adaption to high-throughput screening of small molecule inhibitors of HATs, highlighting the value of this assay strategy in new drug discovery.
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Affiliation(s)
- Tielong Gao
- Department of Chemistry, Georgia State University, Atlanta, GA 30302, USA
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10
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Francis NJ, Rowlands M, Workman P, Jones K, Aherne W. Small-molecule inhibitors of the protein methyltransferase SET7/9 identified in a high-throughput screen. JOURNAL OF BIOMOLECULAR SCREENING 2012; 17:1102-9. [PMID: 22772057 DOI: 10.1177/1087057112452137] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2023]
Abstract
Aberrant expression of chromatin-modifying enzymes (CMEs) is associated with a range of human diseases, including cancer. CMEs are now an important target area in drug discovery. Although the role that histone and protein (lysine) methyltransferases (PMTs) play in the regulation of transcription and cell growth is increasingly recognized, few small-molecule inhibitors of this class of enzyme have been reported. Here we describe an assay suitable for primary compound screening for the identification of PMT inhibitors. The assay followed the methylation of histones in the presence of the PMT SET7/9 and the radioactive cofactor S-adenosyl-methionine using scintillating microplates (FlashPlate) and was used to screen approximately 65 000 compounds (% coefficient of variation = 10%; Z' = 0.6). The hits identified from a library of more than 63 000 diverse small molecules included a series of rhodanine compounds with micromolar activity. A screen of the National Cancer Institute Diversity Set (2000 compounds) identified an orsein derivative that inhibited SET7/9 (~20 µM) and showed modest growth inhibition associated with the expected cellular phenotype of reduced histone methylation in a human tumor cell line. The assay represents a useful tool for the identification of inhibitors of PMT activity.
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Affiliation(s)
- Nicola-Jane Francis
- Cancer Research UK Cancer Therapeutics Unit, Division of Cancer Therapeutics, The Institute of Cancer Research, Haddow Laboratories, Sutton, UK
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Xie W, Ames RS, Li H. A cell-based high-throughput screening assay to measure cellular histone h3 lys27 trimethylation with a modified dissociation-enhanced lanthanide fluorescent immunoassay. ACTA ACUST UNITED AC 2011; 17:99-107. [PMID: 22086723 DOI: 10.1177/1087057111422378] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Histone proteins are subject to several modifications, including phosphorylation, acetylation, methylation, sumoylation, and ubiquitination. These posttranslational modifications play critical roles in chromatin structure and gene transcription. Because of their involvement in the progression of a variety of diseases, histone modifications are attracting increased attention. We report herein a high-throughput DELFIA assay to quantify H3K27me3 in the prostate cancer cell line, PC3. Using a high binding MaxiSorp plate, we were able to eliminate the need for the capture antibody. We also developed an effective method, a combination of "freeze-thaw" and 0.2 N HCl, to extract histone proteins in PC3 cells cultured in a 384-well plate. To compensate for cell viability change, we normalized H3K27me3 signal to the total amount of H3 in each sample well. As a result, we show that the assay has a good dynamic range with a robust assay window. Using a methlytransferase inhibitor, DZNep, we show that the change of H3K27me3 signal is target specific. This method simplifies the logistics in screening and profiling and reduces the cost per well to an acceptable level for high-throughput screening. The findings presented here should be applicable to other assays involving binding and extraction of histone proteins.
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Affiliation(s)
- Wensheng Xie
- Biological Reagents and Assay Development, Platform Technology and Science, GlaxoSmithKline, Collegeville, PA 19426, USA
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12
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Rye PT, Frick LE, Ozbal CC, Lamarr WA. Advances in Label-Free Screening Approaches for Studying Histone Acetyltransferases. ACTA ACUST UNITED AC 2011; 16:1186-95. [DOI: 10.1177/1087057111418653] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Histone acetyltransferases (HATs) catalyze the transfer of an acetyl group from an acetyl-coenzyme A donor molecule to specific lysine residues within proteins. The acetylation state of proteins, particularly histones, is known to modulate their intermolecular binding properties and control various cellular processes, most notably transcriptional activation. In addition, deregulation of HAT activity has been linked to the development of a number of cancers; therefore, compounds that affect these enzymes have strong potential as therapeutic agents. The research presented here demonstrates three label-free HAT screening approaches, all based on the fast and direct measurement of one or more substrate-product pairs by high-throughput mass spectrometry techniques. The first approach involves monitoring all possible acetylation states of a peptide concurrently to measure HAT activity. The second approach measures acetylation reactions, on both peptides and whole protein substrates, via direct detection of the acetyl-coenzyme A cosubstrate and coenzyme A coproduct. Lastly, the authors demonstrate the ability to monitor directly the acetylation state of whole histone proteins in the same high-throughput manner using time-of-flight mass spectrometry. The generation of compound-mediated inhibition data using each of these techniques establishes mass spectrometry as a versatile, label-free, and biologically relevant screening approach to this challenging target class.
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Affiliation(s)
- Peter T. Rye
- Agilent Technologies, Inc., Life Sciences Group, Wakefield, Massachusetts
| | - Lauren E. Frick
- Agilent Technologies, Inc., Life Sciences Group, Wakefield, Massachusetts
| | - Can C. Ozbal
- Agilent Technologies, Inc., Life Sciences Group, Wakefield, Massachusetts
| | - William A. Lamarr
- Agilent Technologies, Inc., Life Sciences Group, Wakefield, Massachusetts
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Kwie FHA, Briet M, Soupaya D, Hoffmann P, Maturano M, Rodriguez F, Blonski C, Lherbet C, Baudoin-Dehoux C. New potent bisubstrate inhibitors of histone acetyltransferase p300: design, synthesis and biological evaluation. Chem Biol Drug Des 2010; 77:86-92. [PMID: 21118378 DOI: 10.1111/j.1747-0285.2010.01056.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Bisubstrate-type compound Lys-CoA has been shown to inhibit the p300 histone acetyl transferase activity efficiently and may constitute a lead compound for a novel class of anticancer therapeutics. Based on this strategy, we synthesized a series of CoA derivatives and evaluated these molecules for their activity as p300 histone acetyltransferases inhibitor. The best activity was obtained with compound 3 bearing a C-5 spacing linker that connects the CoA moiety to a tert-butyloxycarbonyl (Boc) group. Based on docking simulations, this inhibitor exhibits favorable interactions with two binding areas, namely pockets P1 and P2, within the active site.
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Affiliation(s)
- Franciane Ho A Kwie
- CNRS, Laboratoire de Synthèse et Physico-Chimie de Molécules d'Intérêt Biologique, SPCMIB, UMR-5068, 118 Route de Narbonne, Toulouse Cedex 9, France
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14
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Xie N, Elangwe EN, Asher S, Zheng YG. A Dual-Mode Fluorescence Strategy for Screening HAT Modulators. Bioconjug Chem 2009; 20:360-6. [DOI: 10.1021/bc800467a] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Nan Xie
- Department of Chemistry, Georgia State University, PO Box 4098, Atlanta, Georgia 30302
| | - Emilia N. Elangwe
- Department of Chemistry, Georgia State University, PO Box 4098, Atlanta, Georgia 30302
| | - Sabrina Asher
- Department of Chemistry, Georgia State University, PO Box 4098, Atlanta, Georgia 30302
| | - Yujun George Zheng
- Department of Chemistry, Georgia State University, PO Box 4098, Atlanta, Georgia 30302
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15
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Gorsuch S, Bavetsias V, Rowlands MG, Aherne GW, Workman P, Jarman M, McDonald E. Synthesis of isothiazol-3-one derivatives as inhibitors of histone acetyltransferases (HATs). Bioorg Med Chem 2008; 17:467-74. [PMID: 19101154 DOI: 10.1016/j.bmc.2008.11.079] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2008] [Revised: 11/07/2008] [Accepted: 11/26/2008] [Indexed: 02/06/2023]
Abstract
High-throughput screening led to the identification of isothiazolones 1 and 2 as inhibitors of histone acetyltransferase (HAT) with IC50s of 3 microM and 5 microM, respectively. Analogues of these hit compounds with variations of the N-phenyl group, and with variety of substituents at C-4, C-5 of the thiazolone ring, were prepared and assayed for inhibition of the HAT enzyme PCAF. Potency is modestly favoured when the N-aryl group is electron deficient (4-pyridyl derivative 10 has IC(50)=1.5 microM); alkyl substitution at C-4 has little effect, whilst similar substitution at C-5 causes a significant drop in potency. The ring-fused compound 38 has activity (IC(50)=6.1 microM) to encourage further exploration of this bicyclic structure. The foregoing SAR is consistent with an inhibitory mechanism involving cleavage of the S-N bond of the isothiazolone ring by a catalytically important thiol residue.
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Affiliation(s)
- Stephen Gorsuch
- Cancer Research UK Centre for Cancer Therapeutics, The Institute of Cancer Research, Cancer Research UK Laboratories, Cotswold Road, Sutton, Surrey, SM2 5NG, UK
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16
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An easy assay for histone acetyltransferase activity using a PhosphorImager. Anal Biochem 2008; 383:296-300. [DOI: 10.1016/j.ab.2008.08.029] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2008] [Revised: 08/18/2008] [Accepted: 08/26/2008] [Indexed: 11/18/2022]
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17
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Abreu PA, Dellamora-Ortiz G, Leão-Ferreira LR, Gouveia M, Braggio E, Zalcberg I, Santos DO, Bourguinhon S, Cabral LM, Rodrigues CR, Castro HC. DNA methylation: a promising target for the twenty-first century. Expert Opin Ther Targets 2008; 12:1035-47. [PMID: 18620524 DOI: 10.1517/14728222.12.8.1035] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Over the last few years DNA methylation and its involvement in diseases such as cancer has become of great interest for applied research. Since reversal of aberrant DNA methylation may influence the behavior of tumors, the methylation of DNA CpG sites is a potential target for the development of inhibitors for use in cancer treatment. OBJECTIVE/METHODS We briefly review the structural and mechanistic features of DNA methylation, including a structural analysis of the three main human DNA methyltransferases and some (pre)clinical results. RESULTS/CONCLUSION Despite side effects, data obtained to date still support the vision that DNA-methylation, possibly associated with the use of histone deacetylases (HDACs) and/or artificial transcription factors (ATFs), is a promising target for improving anticancer therapy in the 21st century.
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Affiliation(s)
- Paula A Abreu
- Federal Fluminense University, Biology Institute, Department of Celular and Molecular Biology, CEP 24020-150 Niterói, Rio de Janeiro, Brazil
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18
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Glickman JF, Schmid A, Ferrand S. Scintillation Proximity Assays in High-Throughput Screening. Assay Drug Dev Technol 2008; 6:433-55. [DOI: 10.1089/adt.2008.135] [Citation(s) in RCA: 91] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Affiliation(s)
| | - Andres Schmid
- Novartis Institutes for BioMedical Research, Basel, Switzerland
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19
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Abstract
Scintillation proximity assay technologies provide a rapid non-separation method to measure common biological interactions using radioactively tagged molecules. This unit identifies potential uses of the technology for the measurement of receptor-ligand binding, cAMP accumulation, GTP binding to heterotrimeric G proteins, protease activity and cellular uptake.
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Affiliation(s)
- Steven D Kahl
- Lilly Research Laboratories, Indianapolis, Indiana, USA
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20
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Hardcastle A, Tomlin P, Norris C, Richards J, Cordwell M, Boxall K, Rowlands M, Jones K, Collins I, McDonald E, Workman P, Aherne W. A duplexed phenotypic screen for the simultaneous detection of inhibitors of the molecular chaperone heat shock protein 90 and modulators of cellular acetylation. Mol Cancer Ther 2007; 6:1112-22. [PMID: 17363504 DOI: 10.1158/1535-7163.mct-06-0496] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Histone deacetylases (HDACs), histone acetyltransferases (HATs), and the molecular chaperone heat shock protein 90 (HSP90) are attractive anticancer drug targets. High-throughput screening plays a pivotal role in modern molecular mechanism-based drug discovery. Cell-based screens are particularly useful in that they identify compounds that are permeable and active against the selected target or pathway in a cellular context. We have previously developed time-resolved fluorescence cell immunosorbent assays (TRF-Cellisas) for compound screening and pharmacodynamic studies. These assays use a primary antibody to the single protein of interest and a matched secondary immunoglobulin labeled with an europium chelate (Eu). The availability of species-specific secondary antibodies labeled with different lanthanide chelates provides the potential for multiplexing this type of assay. The approach has been applied to the development of a 384-well duplexed cell-based screen to simultaneously detect compounds that induce the co-chaperone HSP70 as a molecular marker of potential inhibitors of HSP90 together with those that modulate cellular acetylation (i.e., potential inhibitors of histone deacetylase or histone acetyltransferase activity). The duplexed assay proved reliable in high-throughput format and approximately 64,000 compounds were screened. Following evaluation in secondary assays, 3 of 13 hits from the HSP70 arm were confirmed. Two of these directly inhibited the intrinsic ATPase activity of HSP90 whereas the third seems to have a different mechanism of action. In the acetylation arm, two compounds increased cellular acetylation, one of which inhibited histone deacetylase activity. A third compound decreased cellular histone acetylation, potentially through a novel mechanism of action.
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Affiliation(s)
- Anthea Hardcastle
- Cancer Research UK Centre for Cancer Therapeutics, The Institute of Cancer Research, Haddow Laboratories, 15 Cotswold Road, Sutton, Surrey SM2 5NG, United Kingdom
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21
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Ito K, Chung KF, Adcock IM. Update on glucocorticoid action and resistance. J Allergy Clin Immunol 2006; 117:522-43. [PMID: 16522450 DOI: 10.1016/j.jaci.2006.01.032] [Citation(s) in RCA: 278] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2006] [Revised: 01/25/2006] [Accepted: 01/25/2006] [Indexed: 12/11/2022]
Abstract
Extensive development of inhaled and oral glucocorticoids has resulted in highly potent molecules that have been optimized to target activity to the lung and minimize systemic exposure. These have proved highly effective for most asthmatic subjects, but despite these developments, there are a number of subjects with asthma who fail to respond to even high doses of inhaled or even oral glucocorticoids. Advances in delineating the fundamental mechanisms of glucocorticoid pharmacology, especially the concepts of transactivation and transrepression and cofactor recruitment, have resulted in better understanding of the molecular mechanisms whereby glucocorticoids suppress inflammation. The existence of multiple mechanisms underlying glucocorticoid insensitivity raises the possibility that this might indeed reflect different diseases with a common phenotype, and studies examining the efficacy of potential new agents should be targeted toward subgroups of patients with severe corticosteroid-resistant asthma who clearly require effective new drugs and other approaches to improved asthma control.
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Affiliation(s)
- Kazuhiro Ito
- Cell and Molecular Biology, Airways Disease Section, National Heart and Lung Institute, Imperial College London, UK
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22
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Berndsen CE, Denu JM. Assays for mechanistic investigations of protein/histone acetyltransferases. Methods 2005; 36:321-31. [PMID: 16085424 DOI: 10.1016/j.ymeth.2005.03.002] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/30/2005] [Indexed: 10/25/2022] Open
Abstract
Protein/histone acetyltransferases (PATs/HATs) have been implicated in a number of cellular functions including gene regulation, DNA synthesis, and repair. This paper reviews methods that can be used to quantitatively determine the activity and ultimately the catalytic/kinetic mechanism of PAT/HATs in vitro. Two methods will be described in detail. The first method is a filter-binding assay that measures the transfer of radiolabeled acetate from acetyl-CoA to protein. The second method is a continuous, spectroscopic, enzyme-coupled assay that links the PAT/HAT reaction to the reduction of NAD+ by pyruvate or alpha-ketoglutarate dehydrogenase. Both methods are highly applicable in determining steady-state reaction rates, and obtaining the kinetic constants Vmax, Km, and V/K from substrate saturation curves. We describe a new application of the filter-binding assay to determine the kinetic parameters for HATs using low concentrations of nucleosomal substrates.
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Affiliation(s)
- Christopher E Berndsen
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, 1300 University Avenue Madison, WI 53706-1532, USA
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23
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Stimson L, Rowlands MG, Newbatt YM, Smith NF, Raynaud FI, Rogers P, Bavetsias V, Gorsuch S, Jarman M, Bannister A, Kouzarides T, McDonald E, Workman P, Aherne GW. Isothiazolones as inhibitors of PCAF and p300 histone acetyltransferase activity. Mol Cancer Ther 2005; 4:1521-32. [PMID: 16227401 DOI: 10.1158/1535-7163.mct-05-0135] [Citation(s) in RCA: 158] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Histone acetylation plays an important role in regulating the chromatin structure and is tightly regulated by two classes of enzyme, histone acetyltransferases (HAT) and histone deacetylases (HDAC). Deregulated HAT and HDAC activity plays a role in the development of a range of cancers. Consequently, inhibitors of these enzymes have potential as anticancer agents. Several HDAC inhibitors have been described; however, few inhibitors of HATs have been disclosed. Following a FlashPlate high-throughput screen, we identified a series of isothiazolone-based HAT inhibitors. Thirty-five N-substituted analogues inhibited both p300/cyclic AMP-responsive element binding protein-binding protein-associated factor (PCAF) and p300 (1 to >50 micromol/L, respectively) and the growth of a panel of human tumor cell lines (50% growth inhibition, 0.8 to >50 micromol/L). CCT077791 and CCT077792 decreased cellular acetylation in a time-dependent manner (2-48 hours of exposure) and a concentration-dependent manner (one to five times, 72 hours, 50% growth inhibition) in HCT116 and HT29 human colon tumor cell lines. CCT077791 reduced total acetylation of histones H3 and H4, levels of specific acetylated lysine marks, and acetylation of alpha-tubulin. Four and 24 hours of exposure to the compounds produced the same extent of growth inhibition as 72 hours of continuous exposure, suggesting that growth arrest was an early event. Chemical reactivity of these compounds, as measured by covalent protein binding and loss of HAT inhibition in the presence of DTT, indicated that reaction with thiol groups might be important in their mechanism of action. As one of the first series of small-molecule inhibitors of HAT activity, further analogue synthesis is being pursued to examine the potential scope for reducing chemical reactivity while maintaining HAT inhibition.
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Affiliation(s)
- Lindsay Stimson
- Cancer Research UK Centre for Cancer Therapeutics at the Institute of Cancer Research, Haddow Laboratories, 15 Cotswold Road, Sutton, Surrey SM2 5NG, United Kingdom
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24
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Hayashi R, Wada H, Ito K, Adcock IM. Effects of glucocorticoids on gene transcription. Eur J Pharmacol 2005; 500:51-62. [PMID: 15464020 DOI: 10.1016/j.ejphar.2004.07.011] [Citation(s) in RCA: 179] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/01/2004] [Indexed: 01/06/2023]
Abstract
Glucocorticoids bind to and activate a cytoplasmic glucocorticoid receptor. The activated glucocorticoid receptor translocates into the nucleus and binds to specific response elements in the promoter regions of anti-inflammatory genes such as lipocortin-1 and secretory leukocyte protease inhibitor (SLPI). However, the major anti-inflammatory effects of glucocorticoids appear to be due largely to interaction between the activated glucocorticoid receptor and transcription factors, notably nuclear factor-kappaB (NF-kappaB) and activator protein-1 (AP-1), that mediate the expression of inflammatory genes. NF-kappaB switches on inflammatory genes via a process involving recruitment of transcriptional co-activator proteins and changes in chromatin modifications such as histone acetylation. This process must occur in the correct temporal manner to allow for effective inflammatory gene expression to occur. The interactions between NF-kappaB and the glucocorticoid receptor result in differing effects on histone modifications and chromatin remodelling. Drugs that enhance glucocorticoid receptor nuclear translocation (long acting beta-agonists) and GR-associated histone deacetylases activity (theophylline) have been shown to be effective add-on therapies. In addition, dissociated glucocorticoids that target NF-kappaB preferentially have also been successful in the treatment of allergic disease.
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Affiliation(s)
- Ryuji Hayashi
- Department of Thoracic Medicine, National Heart and Lung Institute, Imperial College, Dovehouse St, London, SW3 6LY, UK
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25
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Sun C, Newbatt Y, Douglas L, Workman P, Aherne W, Linardopoulos S. High-throughput screening assay for identification of small molecule inhibitors of Aurora2/STK15 kinase. ACTA ACUST UNITED AC 2005; 9:391-7. [PMID: 15296638 DOI: 10.1177/1087057104264071] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
STK15/Aurora2 is a centrosome-associated serine/threonine kinase, the protein levels and kinase activity of which rise during G2 and mitosis. STK15 overexpression induces tumorigenesis and is amplified in various human cancers and tumor cell lines. Thus, STK15 represents an important therapeutic target for small molecule inhibitors that would disrupt its activity and block cell proliferation. The availability of a robust and selective small molecule inhibitor would also provide a useful tool for identification of the potential role of STK15 in cell cycle regulation and tumor development. The authors report the development of a novel, fast, simple microplate assay for STK15 activity suitable for high-throughput screening. In the assay, gamma-(33)P-ATP and STK15 were incubated in a myelin basic protein (MBP)-coated FlashPlate(R) to generate a scintillation signal. The assay was reproducible, the signal-to-noise ratio was high (11) and the Z' factor was 0.69. The assay was easily adapted to a robotic system for drug discovery programs targeting STK15. The authors also demonstrate that STK15 is regulated by phosphorylation and the N-amino terminal domain of the protein. Treatment with phosphatase inhibitors (okadaic acid) or deletion of the N-amino terminal domain results in a significant increase in the enzymatic activity.
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Affiliation(s)
- Chongbo Sun
- Cancer Research UK, Centre for Cancer Therapeutics, Sutton, Surrey SM2 5NG, UK
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26
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Funk CJ, Davis AS, Hopkins JA, Middleton KM. Development of high-throughput screens for discovery of kinesin adenosine triphosphatase modulators. Anal Biochem 2005; 329:68-76. [PMID: 15136168 DOI: 10.1016/j.ab.2004.02.032] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2003] [Indexed: 10/26/2022]
Abstract
Kinesins are a group of related molecular motor proteins that have great potential as targets for antimitotic drug development. We have developed two novel assays, one end-point and one kinetic, that are useful for the discovery and optimization of kinesin modulators. Both assays measure inorganic phosphate (Pi) generated by microtubule-activated kinesin adenosine triphosphatase activity. The assays were validated using the mitotic Eg5 kinesin-specific inhibitor, monastrol. A panel of nine kinesin motor domain proteins, representing 8 of the 14 classes of kinesins, was screened. The coefficient of variation for both assays was determined to be 4-14% depending on the panel member. Using the Eg5 kinetic assay with monastrol the IC50 value was 12 microM, which agrees well with previously published results. Two other closely related mitotic kinesins (AnBimC and MKLP1) were found to have IC50 values in the millimolar range. The other panel members (kinesin heavy chain, chromokinesin KIF4A, KIF3C, CENP-E, MCAK, and KIFC3) were not significantly inhibited by millimolar levels of monastrol. It is anticipated that screening of the nine-member panel of kinesins in these assays will serve as a platform for the discovery and development of specific kinesin modulators.
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Affiliation(s)
- C Joel Funk
- Cytoskeleton, Inc., 1830 S. Acoma, Denver, CO 80223, USA
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27
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Adcock IM, Cosio B, Tsaprouni L, Barnes PJ, Ito K. Redox regulation of histone deacetylases and glucocorticoid-mediated inhibition of the inflammatory response. Antioxid Redox Signal 2005; 7:144-52. [PMID: 15650403 DOI: 10.1089/ars.2005.7.144] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Gene expression, at least in part, is regulated by changes in histone acetylation status induced by activation of the proinflammatory redox-sensitive transcription factors activator protein-1 (AP-1) and nuclear factor-kappaB (NF-kappaB). Hyperacetylated histone is associated with open actively transcribed DNA and enhanced inflammatory gene expression. In contrast, hypoacetylated histone is linked to a closed repressed DNA state and a lack of gene expression. The degree of inflammatory gene expression is a result of a balance between histone acetylation and histone deacetylation. One of the major mechanisms of glucocorticoid function is to recruit histone deacetylase enzymes to the site of active gene expression, thus reducing inflammation. Oxidative stress can enhance inflammatory gene expression by further stimulating AP-1- and NF-kappaB-mediated gene expression and elevating histone acetylation. In addition, oxidants can reduce glucocorticoid function by attenuating histone deacetylase activity and expression. Thus, oxidant stress, acting through changes in chromatin structure, can enhance inflammation and induce a state of relative glucocorticoid insensitivity. This may account for the lack of glucocorticoid sensitivity in patients with chronic obstructive pulmonary disease. Antioxidants should reduce the inflammation and restore glucocorticoid sensitivity in these subjects.
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Affiliation(s)
- Ian M Adcock
- Thoracic Medicine, National Heart and Lung Institute, Imperial College London, London, UK.
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28
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Thompson PR, Wang D, Wang L, Fulco M, Pediconi N, Zhang D, An W, Ge Q, Roeder RG, Wong J, Levrero M, Sartorelli V, Cotter RJ, Cole PA. Regulation of the p300 HAT domain via a novel activation loop. Nat Struct Mol Biol 2004; 11:308-15. [PMID: 15004546 DOI: 10.1038/nsmb740] [Citation(s) in RCA: 331] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2003] [Accepted: 01/28/2004] [Indexed: 01/27/2023]
Abstract
The transcriptional coactivator p300 is a histone acetyltransferase (HAT) whose function is critical for regulating gene expression in mammalian cells. However, the molecular events that regulate p300 HAT activity are poorly understood. We evaluated autoacetylation of the p300 HAT protein domain to determine its function. Using expressed protein ligation, the p300 HAT protein domain was generated in hypoacetylated form and found to have reduced catalytic activity. This basal catalytic rate was stimulated by autoacetylation of several key lysine sites within an apparent activation loop motif. This post-translational modification and catalytic regulation of p300 HAT activity is conceptually analogous to the activation of most protein kinases by autophosphorylation. We therefore propose that this autoregulatory loop could influence the impact of p300 on a wide variety of signaling and transcriptional events.
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Affiliation(s)
- Paul R Thompson
- Department of Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
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29
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Abstract
Glucocorticoids are widely used to treat inflammatory and immune diseases. The most common use of glucocorticoids today is in the treatment of asthma. Inhaled glucocorticoids are first-line treatment in adults and children with persistent asthma, the most common chronic airway inflammatory disease. Our knowledge of how glucocorticoids suppress inflammation is based on recent developments in understanding the fundamental mechanisms of gene transcription, namely recruitment of histone-modifying co-factors. The determination of the crystal structure of the ligand-binding domain of the human glucocorticoid receptor (GR) has advanced our understanding of how ligands interact with GR and provide a glimpse of a future of rational drug design based on "space-filling" structures with dissociated properties. This might have important clinical implications, leading to a better understanding of the inflammatory mechanisms of many diseases and might signal the development of new anti-inflammatory treatments in the future.
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Affiliation(s)
- Ian M Adcock
- Department of Thoracic Medicine, National Heart and Lung Institute, Dovehouse St., London SW3 6LY, UK.
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30
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Aherne GW, McDonald E, Workman P. Finding the needle in the haystack: why high-throughput screening is good for your health. Breast Cancer Res 2002; 4:148-54. [PMID: 12100740 PMCID: PMC138735 DOI: 10.1186/bcr440] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2002] [Revised: 05/02/2002] [Accepted: 05/09/2002] [Indexed: 11/10/2022] Open
Abstract
High-throughput screening is an essential component of the toolbox of modern technologies that improve speed and efficiency in contemporary cancer drug development. This is particularly important as we seek to exploit, for maximum therapeutic benefit, the large number of new molecular targets emerging from the Human Genome Project and cancer genomics. Screening of diverse collections of low molecular weight compounds plays a key role in providing chemical starting points for iterative optimisation by medicinal chemistry. Examples of successful drug discovery programmes based on high-throughput screening are described, and these offer potential in the treatment of breast cancer and other malignancies.
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Affiliation(s)
- G Wynne Aherne
- Cancer Research UK Centre for Cancer Therapeutics, The Institute of Cancer Research, Sutton, UK
| | - Edward McDonald
- Cancer Research UK Centre for Cancer Therapeutics, The Institute of Cancer Research, Sutton, UK
| | - Paul Workman
- Cancer Research UK Centre for Cancer Therapeutics, The Institute of Cancer Research, Sutton, UK
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31
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Abstract
Deaths from breast cancer have fallen markedly over the past decade due, in part, to the use of endocrine agents that reduce the levels of circulating oestrogens or compete with oestrogen for binding to its receptor. However, many breast tumours either fail to respond or become resistant to endocrine therapies. By understanding the mechanisms that underlie this resistance, we might be able to develop strategies for overcoming or bypassing it.
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Affiliation(s)
- Simak Ali
- Department of Cancer Medicine and Cancer Research Campaign Laboratories, Faculty of Medicine, Imperial College of Science, Technology & Medicine, Hammersmith Hospital, Du Cane Road, London W12 0NN, UK.
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