601
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Raskatov JA, Meier JL, Puckett JW, Yang F, Ramakrishnan P, Dervan PB. Modulation of NF-κB-dependent gene transcription using programmable DNA minor groove binders. Proc Natl Acad Sci U S A 2012; 109:1023-8. [PMID: 22203967 PMCID: PMC3268328 DOI: 10.1073/pnas.1118506109] [Citation(s) in RCA: 100] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Nuclear factor κB (NF-κB) is a transcription factor that regulates various aspects of immune response, cell death, and differentiation as well as cancer. In this study we introduce the Py-Im polyamide 1 that binds preferentially to the sequences 5'-WGGWWW-3' and 5'GGGWWW-3'. The compound is capable of binding to κB sites and reducing the expression of various NF-κB-driven genes including IL6 and IL8 by qRT-PCR. Chromatin immunoprecipitation experiments demonstrate a reduction of p65 occupancy within the proximal promoters of those genes. Genome-wide expression analysis by RNA-seq compares the DNA-binding polyamide with the well-characterized NF-κB inhibitor PS1145, identifies overlaps and differences in affected gene groups, and shows that both affect comparable numbers of TNF-α-inducible genes. Inhibition of NF-κB DNA binding via direct displacement of the transcription factor is a potential alternative to the existing antagonists.
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Affiliation(s)
| | | | | | - Fei Yang
- Division of Chemistry and Chemical Engineering and
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602
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Chacon A, Zagol-Ikapitte I, Amarnath V, Reyzer ML, Oates JA, Caprioli RM, Boutaud O. On-tissue chemical derivatization of 3-methoxysalicylamine for MALDI-imaging mass spectrometry. J Mass Spectrom 2011; 46:840-6. [PMID: 21834023 PMCID: PMC3174490 DOI: 10.1002/jms.1958] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
MALDI-imaging mass spectrometry (IMS) has been shown to be a powerful tool to study drug distributions in organ tissue as well as whole animal bodies. Nevertheless, not all drugs are amenable to MALDI while others may be limited by poor sensitivity poor sensitivity. The use of chemical derivatization to improve detection of small molecules by mass spectrometry techniques is well documented. To our knowledge, however, this approach has not been applied to direct tissue analysis of small organic molecules. In this manuscript, we demonstrate the use of on-tissue chemical derivatization of a small organic molecule, 3-methoxysalicylamine (3-MoSA) a scavenger of γ-ketoaldehydes. Derivatization of 3-MoSA with 1,1'-thiocarbonyldiimidazole (TCDI) results in an oxothiazolidine derivative which is detected with much greater sensitivity by MALDI than 3-MoSA itself. TCDI treatment of tissue from mice dosed with 3-MoSA allowed images to be obtained showing its spatial distribution as well as its pharmacokinetic profile in different organs. These images correlated well with results obtained from HPLC-MS/MS analyses of the same tissues. These results provide proof-of-concept that on-tissue chemical derivatization can be used to improve detection of a small organic molecule by MALDI-IMS.
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Affiliation(s)
- Almary Chacon
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232-6602, USA
| | - Irene Zagol-Ikapitte
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232-6602, USA
| | | | - Michelle L. Reyzer
- Mass Spectrometry Research Center, Vanderbilt University, Nashville, TN 37232-6602, USA
| | - John A. Oates
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232-6602, USA
- Department of Medicine, Vanderbilt University, Nashville, TN 37232-6602, USA
| | - Richard M. Caprioli
- Mass Spectrometry Research Center, Vanderbilt University, Nashville, TN 37232-6602, USA
- Department of Medicine, Vanderbilt University, Nashville, TN 37232-6602, USA
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232-6602, USA
| | - Olivier Boutaud
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232-6602, USA
- Correspondence to: Olivier Boutaud, Division of Clinical Pharmacology, Department of Pharmacology, Vanderbilt University, Nashville, TN 37232-6602, USA.
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603
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Dias JA, Bonnet B, Weaver BA, Watts J, Kluetzman K, Thomas RM, Poli S, Mutel V, Campo B. A negative allosteric modulator demonstrates biased antagonism of the follicle stimulating hormone receptor. Mol Cell Endocrinol 2011; 333:143-50. [PMID: 21184806 PMCID: PMC4491433 DOI: 10.1016/j.mce.2010.12.023] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2010] [Revised: 12/15/2010] [Accepted: 12/15/2010] [Indexed: 01/07/2023]
Abstract
High quality gamete production in males and females requires the pituitary gonadotropin follicle stimulating hormone (FSH). In this report a novel chemical class of small molecule inhibitors of FSH receptor (FSHR) is described. ADX61623, a negative allosteric modulator (NAM), increased the affinity of interaction between (125)I-hFSH and human FSHR (hFSHR) five fold. This form of FSHR occupied simultaneously by FSH and ADX61623 was inactive for cAMP and progesterone production in primary cultures of rat granulosa cells. In contrast, ADX61623 did not block estrogen production. This demonstrates for the first time, biased antagonism at the FSHR. To determine if ADX61623 blocked FSH induction of follicle development in vivo, a bioassay to measure follicular development and oocyte production in immature female rats was validated. ADX61623 was not completely effective in blocking FSH induced follicular development in vivo at doses up to 100mg/kg as oocyte production and ovarian weight gain were only moderately reduced. These data illustrate that FSHR couples to multiple signaling pathways in vivo. Suppression of one pool of FSHR uncouples Gαs and cAMP production, and decreases progesterone production. Occupancy of another pool of FSHR sensitizes granulosa cells to FSH induced estradiol production. Therefore, ADX61623 is a useful tool to investigate further the mechanism of the FSHR signaling dichotomy. This may lead to a greater understanding of the signaling infrastructure which enables estrogen biosynthesis and may prove useful in treating estrogen dependent disease.
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Affiliation(s)
- James A Dias
- Wadsworth Center, David Axelrod Institute for Public Health, New York State Department of Health, Albany, NY 12208, United States.
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604
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Abstract
HIV-1 integrase (IN) is one of three essential enzymes for viral replication, and is a focus of ardent antiretroviral drug discovery and development efforts. Diligent research has led to the development of the strand-transfer-specific chemical class of IN inhibitors, with two compounds from this group, raltegravir and elvitegravir, advancing the farthest in the US Food and Drug Administration (FDA) approval process for any IN inhibitor discovered thus far. Raltegravir, developed by Merck & Co., has been approved by the FDA for HIV-1 therapy, whereas elvitegravir, developed by Gilead Sciences and Japan Tobacco, has reached phase III clinical trials. Although this is an undoubted success for the HIV-1 IN drug discovery field, the emergence of HIV-1 IN strand-transfer-specific drug-resistant viral strains upon clinical use of these compounds is expected. Furthermore, the problem of strand-transfer-specific IN drug resistance will be exacerbated by the development of cross-resistant viral strains due to an overlapping binding orientation at the IN active site and an equivalent inhibitory mechanism for the two compounds. This inevitability will result in no available IN-targeted therapeutic options for HIV-1 treatment-experienced patients. The development of allosterically targeted IN inhibitors presents an extremely advantageous approach for the discovery of compounds effective against IN strand-transfer drug-resistant viral strains, and would likely show synergy with all available FDA-approved antiretroviral HIV-1 therapeutics, including the IN strand-transfer-specific compounds. Herein we review the concept of allosteric IN inhibition, and the small molecules that have been investigated to bind non-active-site regions to inhibit IN function.
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Affiliation(s)
- Laith Q. Al-Mawsawi
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, 1985 Zonal Avenue, Los Angeles, California 90089
| | - Nouri Neamati
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, 1985 Zonal Avenue, Los Angeles, California 90089
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605
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Yap JL, Worlikar S, MacKerell AD, Shapiro P, Fletcher S. Small-molecule inhibitors of the ERK signaling pathway: Towards novel anticancer therapeutics. ChemMedChem 2011; 6:38-48. [PMID: 21110380 PMCID: PMC3477473 DOI: 10.1002/cmdc.201000354] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2010] [Indexed: 11/09/2022]
Affiliation(s)
| | | | - Alexander D. MacKerell
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, 20 Penn Street, Baltimore, MD 21201, Fax: (+) 1 410 706 5017
| | - Paul Shapiro
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, 20 Penn Street, Baltimore, MD 21201, Fax: (+) 1 410 706 5017
| | - Steven Fletcher
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, 20 Penn Street, Baltimore, MD 21201, Fax: (+) 1 410 706 5017
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606
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Grove KJ, Frappier SL, Caprioli RM. Matrix pre-coated MALDI MS targets for small molecule imaging in tissues. J Am Soc Mass Spectrom 2011; 22:192-5. [PMID: 21472558 PMCID: PMC4151471 DOI: 10.1007/s13361-010-0013-8] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2010] [Revised: 10/07/2010] [Accepted: 10/11/2010] [Indexed: 05/07/2023]
Abstract
A new sample preparation method for MALDI tissue imaging has been developed for the analysis of low molecular weight compounds that employs matrix pre-coated MALDI targets. Tissue sections need only to be transferred onto the pre-coated target before analysis for fast and easy sample preparation. Pre-coated targets have a homogenous matrix coating with uniform crystals of approximately 1-2 μm and do not require solvents that may lead to analyte delocalization within a tissue section. We report here the use of matrix pre-coated targets for imaging of lipids, peptides, and pharmaceuticals in tissues.
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Affiliation(s)
- Kerri J Grove
- Departments of Chemistry, Biochemistry, and the Mass Spectrometry Research Center, Vanderbilt University, MRB3, 465 21st Ave S, Nashville, TN 37235, USA
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607
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Klusa VZ, Isajevs S, Svirina D, Pupure J, Beitnere U, Rumaks J, Svirskis S, Jansone B, Dzirkale Z, Muceniece R, Kalvinsh I, Vinters HV. Neuroprotective properties of mildronate, a small molecule, in a rat model of Parkinson's disease. Int J Mol Sci 2010; 11:4465-87. [PMID: 21151450 PMCID: PMC3000094 DOI: 10.3390/ijms11114465] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2010] [Revised: 10/22/2010] [Accepted: 10/27/2010] [Indexed: 11/16/2022] Open
Abstract
Previously, we have found that mildronate [3-(2,2,2-trimethylhydrazinium) propionate dihydrate], a small molecule with charged nitrogen and oxygen atoms, protects mitochondrial metabolism that is altered by inhibitors of complex I and has neuroprotective effects in an azidothymidine-neurotoxicity mouse model. In the present study, we investigated the effects of mildronate in a rat model of Parkinson's disease (PD) that was generated via a unilateral intrastriatal injection of the neurotoxin 6-hydroxydopamine (6-OHDA). We assessed the expression of cell biomarkers that are involved in signaling cascades and provide neural and glial integration: the neuronal marker TH (tyrosine hydroxylase); ubiquitin (a regulatory peptide involved in the ubiquitin-proteasome degradation system); Notch-3 (a marker of progenitor cells); IBA-1 (a marker of microglial cells); glial fibrillary acidic protein, GFAP (a marker of astrocytes); and inducible nitric oxide synthase, iNOS (a marker of inflammation). The data show that in the 6-OHDA-lesioned striatum, mildronate completely prevented the loss of TH, stimulated Notch-3 expression and decreased the expression of ubiquitin, GFAP and iNOS. These results provide evidence for the ability of mildronate to control the expression of an array of cellular proteins and, thus, impart multi-faceted homeostatic mechanisms in neurons and glial cells in a rat model of PD. We suggest that the use of mildronate provides a protective effect during the early stages of PD that can delay or halt the progression of this neurodegenerative disease.
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Affiliation(s)
- Vija Z. Klusa
- Department of Pharmacology, Faculty of Medicine, University of Latvia, Riga, Latvia
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +371-292-762-63; Fax: +371-673-663-06
| | - Sergejs Isajevs
- Department of Pathology, Faculty of Medicine, University of Latvia, Riga, Latvia
| | - Darja Svirina
- Department of Pathology, Faculty of Medicine, University of Latvia, Riga, Latvia
| | - Jolanta Pupure
- Department of Pharmacology, Faculty of Medicine, University of Latvia, Riga, Latvia
| | - Ulrika Beitnere
- Department of Pharmacology, Faculty of Medicine, University of Latvia, Riga, Latvia
| | - Juris Rumaks
- Department of Pharmacology, Faculty of Medicine, University of Latvia, Riga, Latvia
| | - Simons Svirskis
- Department of Pharmacology, Faculty of Medicine, University of Latvia, Riga, Latvia
| | - Baiba Jansone
- Department of Pharmacology, Faculty of Medicine, University of Latvia, Riga, Latvia
| | - Zane Dzirkale
- Department of Pharmacology, Faculty of Medicine, University of Latvia, Riga, Latvia
| | - Ruta Muceniece
- Department of Pharmacology, Faculty of Medicine, University of Latvia, Riga, Latvia
| | | | - Harry V. Vinters
- Department of Pathology and Laboratory of Medicine and Neurology, University of California Los Angeles, Los Angeles, CA, USA
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608
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Mitchell J. Small molecule immunosensing using surface plasmon resonance. Sensors (Basel) 2010; 10:7323-46. [PMID: 22163605 DOI: 10.3390/s100807323] [Citation(s) in RCA: 118] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/18/2010] [Revised: 07/15/2010] [Accepted: 07/25/2010] [Indexed: 11/17/2022]
Abstract
Surface plasmon resonance (SPR) biosensors utilize refractive index changes to sensitively detect mass changes at noble metal sensor surface interfaces. As such, they have been extensively applied to immunoassays of large molecules, where their high mass and use of sandwich immunoassay formats can result in excellent sensitivity. Small molecule immunosensing using SPR is more challenging. It requires antibodies or high-mass or noble metal labels to provide the required signal for ultrasensitive assays. Also, it can suffer from steric hindrance between the small antigen and large antibodies. However, new studies are increasingly meeting these and other challenges to offer highly sensitive small molecule immunosensor technologies through careful consideration of sensor interface design and signal enhancement. This review examines the application of SPR transduction technologies to small molecule immunoassays directed to different classes of small molecule antigens, including the steroid hormones, toxins, drugs and explosives residues. Also considered are the matrix effects resulting from measurement in chemically complex samples, the construction of stable sensor surfaces and the development of multiplexed assays capable of detecting several compounds at once. Assay design approaches are discussed and related to the sensitivities obtained.
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609
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Galzi JL, Hachet-Haas M, Bonnet D, Daubeuf F, Lecat S, Hibert M, Haiech J, Frossard N. Neutralizing endogenous chemokines with small molecules. Principles and potential therapeutic applications. Pharmacol Ther 2010; 126:39-55. [PMID: 20117133 PMCID: PMC7112609 DOI: 10.1016/j.pharmthera.2009.12.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2009] [Accepted: 12/24/2009] [Indexed: 02/08/2023]
Abstract
Regulation of cellular responses to external stimuli such as hormones, neurotransmitters, or cytokines is achieved through the control of all steps of the complex cascade starting with synthesis, going through maturation steps, release, distribution, degradation and/or uptake of the signalling molecule interacting with the target protein. One possible way of regulation, referred to as scavenging or neutralization of the ligand, has been increasingly studied, especially for small protein ligands. It shows innovative potential in chemical biology approaches as well as in disease treatment. Neutralization of protein ligands, as for example cytokines or chemokines can lead to the validation of signalling pathways under physiological or pathophysiological conditions, and in certain cases, to the development of therapeutic molecules now used in autoimmune diseases, chronic inflammation and cancer treatment. This review explores the field of ligand neutralization and tries to determine to what extent small chemical molecules could substitute for neutralizing antibodies in therapeutic approaches.
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Affiliation(s)
- Jean-Luc Galzi
- IREBS, FRE3211, Ecole Supérieure de Biotechnologie de Strasbourg, Boulevard Sébastien Brant, 67412 Illkirch, France.
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610
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Abstract
The biologic role of thyroid-stimulating hormone (TSH; thyrotropin) as an activator (agonist) of the TSH receptor (TSHR) in the hypothalamic-pituitary-thyroid axis is well known and activation of TSHR by recombinant human TSH is used clinically in patients with thyroid cancer. TSHR ligands other than TSH could be used to probe TSHR biology in thyroidal and extrathyroidal tissues, and potentially be employed in patients. A number of different TSHR ligands have been reported, including TSH analogs, antibodies and small-molecule, drug-like compounds. In this review, we will provide an update on all these classes of TSHR agonists and antagonists but place emphasis on small-molecule ligands.
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Affiliation(s)
- Susanne Neumann
- Clinical Endocrinology Branch, NIDDK, NIH, 50 South Drive, Bethesda, MD 20892-28029, USA, Tel.: +1 301 451 6324, Fax: +1 301 480 4214
| | - Bruce M Raaka
- Clinical Endocrinology Branch, NIDDK, NIH, 50 South Drive, Bethesda, MD 20892-28029, USA, Tel.: +1 301 451 6307, Fax: +1 301 480 4214
| | - Marvin C Gershengorn
- Author for correspondence: Clinical Endocrinology Branch, NIDDK, NIH, 50 South Drive, Bethesda, MD 20892-28029, USA, Tel.: +1 301 451 6305, Fax: +1 301 480 4214,
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611
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Affiliation(s)
- Christopher L Brooks
- Institute for Cancer Genetics, and Department of Pathology, College of Physicians & Surgeons, Columbia University, New York, NY 10032, USA
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612
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Janovick JA, Maya-Núñez G, Ulloa-Aguirre A, Huhtaniemi IT, Dias JA, Verbost P, Conn PM. Increased plasma membrane expression of human follicle-stimulating hormone receptor by a small molecule thienopyr(im)idine. Mol Cell Endocrinol 2009; 298:84-8. [PMID: 18848862 PMCID: PMC2630403 DOI: 10.1016/j.mce.2008.09.015] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2008] [Revised: 09/05/2008] [Accepted: 09/10/2008] [Indexed: 12/12/2022]
Abstract
A thienopyr(im)idine (Org41841) activates the luteinizing hormone (LH) receptor but does not compete with the natural ligand binding site and does not show agonistic action on the follicle-stimulating hormone receptor (hFSHR) at sub-millimolar concentrations. When this drug is preincubated at sub-micromolar concentrations with host cells expressing the hFSHR, and then washed out, binding analysis and assessment of receptor-effector coupling show that it increases plasma membrane expression of the hFSHR. Real-time PCR shows that this effect did not result from increased hFSHR mRNA accumulation. It is possible that Org41841 behaves as a pharmacoperone, a drug which increases the percentage of newly synthesized receptor routing to the membrane. Like pharmacoperones for other receptors, this drug was able to rescue a particular mutant hFSHR (A(189)V) associated with misrouting and endoplasmic reticulum retention, although other mutants could not be rescued. This is potentially the first member of the pharmacoperone drug class which binds at a site that is distinctive from the ligand binding site.
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Affiliation(s)
| | - Guadalupe Maya-Núñez
- Research Unit in Reproductive Medicine, Hospital de Ginecobstetricia “Luis Castelazo Ayala”, Instituto Mexicano del Seguro Social, Mexico D.F., Mexico
| | - Alfredo Ulloa-Aguirre
- Oregon National Primate Research Center, Beaverton, OR, USA
- Research Unit in Reproductive Medicine, Hospital de Ginecobstetricia “Luis Castelazo Ayala”, Instituto Mexicano del Seguro Social, Mexico D.F., Mexico
| | - Ilpo T. Huhtaniemi
- Department of Reproductive Biology, Imperial College London, Hammersmith Campus, Du Cane Road, London W12 NN, UK
| | - James A. Dias
- Wadsworth Center, New York State Department of Health, David Axelrod Institute, 120 New Scotland Avenue, Albany, N.Y. 12208
| | - Pieter Verbost
- Dept. of Pharmacology, Schering-Plough Corporation, P.O. Box 20, 5340 BH Oss, The Netherlands
| | - P. Michael Conn
- Oregon National Primate Research Center, Beaverton, OR, USA
- Research Unit in Reproductive Medicine, Hospital de Ginecobstetricia “Luis Castelazo Ayala”, Instituto Mexicano del Seguro Social, Mexico D.F., Mexico
- Departments of Physiology and Pharmacology, and Cell and Developmental Biology, Oregon Health Sciences University, Portland, OR, USA
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613
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Varadwaj PK, Lahiri T. Functional group based Ligand binding affinity scoring function at atomic environmental level. Bioinformation 2009; 3:268-74. [PMID: 19255647 PMCID: PMC2646862 DOI: 10.6026/97320630003268] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2008] [Accepted: 12/06/2008] [Indexed: 11/23/2022] Open
Abstract
Use of knowledge based scoring function (KBSF) for virtual screening and molecular docking has become an established method for drug discovery. Lack of a precise and reliable free energy function that describes several interactions including water-mediated atomic interaction between amino-acid residues and ligand makes distance based statistical measure as the only alternative. Till now all the distance based scoring functions in KBSF arena use atom singularity concept, which neglects the environmental effect of the atom under consideration. We have developed a novel knowledge-based statistical energy function for protein-ligand complexes which takes atomic environment in to account hence functional group as a singular entity. The proposed knowledge based scoring function is fast, simple to construct, easy to use and moreover it tackle the existing problem of handling molecular orientation in active site pocket. We have designed and used Functional group based Ligand retrieval (FBLR) system which can identify and detect the orientation of functional groups in ligand. This decoy searching was used to build the above KBSF to quantify the activity and affinity of high resolution protein-ligand complexes. We have proposed the probable use of these decoys in molecular build-up as a de-novo drug designing approach. We have also discussed the possible use of the said KSBF in pharmacophore fragment detection and pseudo center based fragment alignment procedure.
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614
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Johnson RL, Huang W, Jadhav A, Austin CP, Inglese J, Martinez ED. A quantitative high-throughput screen identifies potential epigenetic modulators of gene expression. Anal Biochem 2008; 375:237-48. [PMID: 18211814 PMCID: PMC2330280 DOI: 10.1016/j.ab.2007.12.028] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2007] [Revised: 12/20/2007] [Accepted: 12/21/2007] [Indexed: 11/24/2022]
Abstract
Epigenetic regulation of gene expression is essential in embryonic development and contributes to cancer pathology. We used a cell-based imaging assay that measures derepression of a silenced green fluorescent protein (GFP) reporter to identify novel classes of compounds involved in epigenetic regulation. This locus derepression (LDR) assay was screened against a 69,137-member chemical library using quantitative high-throughput screening (qHTS), a titration-response method that assays compounds at multiple concentrations. From structure-activity relationships of the 411 actives recovered from the qHTS, 6 distinct chemical series were chosen for further study. A total of 48 qHTS actives and analogs were counterscreened using the parental line of the LDR cells, which lack the GFP reporter. Three series-8-hydroxy quinoline, quinoline-8-thiol, and 1,3,5-thiadiazinane-2-thione-were not fluorescent and reconfirmed activity in the LDR cells. The three active series did not inhibit histone deacetylase activity in nuclear extracts or reactivate the expression of the densely methylated p16 gene in cancer cells. However, one series induced expression of the methylated CDH13 gene and inhibited the viability of several lung cancer lines at submicromolar concentrations. These results suggest that the identified small molecules act on epigenetic or transcriptional components and validate our approach of using a cell-based imaging assay in conjunction with qHTS.
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Affiliation(s)
- Ronald L. Johnson
- NIH Chemical Genomics Center, National Institutes of Health, Bethesda, MD 20892-3370
| | - Wenwei Huang
- NIH Chemical Genomics Center, National Institutes of Health, Bethesda, MD 20892-3370
| | - Ajit Jadhav
- NIH Chemical Genomics Center, National Institutes of Health, Bethesda, MD 20892-3370
| | - Christopher P. Austin
- NIH Chemical Genomics Center, National Institutes of Health, Bethesda, MD 20892-3370
| | - James Inglese
- NIH Chemical Genomics Center, National Institutes of Health, Bethesda, MD 20892-3370
| | - Elisabeth D. Martinez
- Hamon Center for Therapeutic Oncology Research, University of Texas Southwestern Medical Center at Dallas, 6000 Harry Hines Blvd., Dallas, TX 75390-8593
- Department of Pharmacology, University of Texas Southwestern Medical Center at Dallas, 6000 Harry Hines Blvd., Dallas, TX 75390-8593
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615
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Abstract
Using a pyrrole-based scaffold, we developed a series of small molecules that mimic the three-dimensional arrangement of the polar and hydrophobic functional groups of the best cyclic-peptide inhibitor. Iterative optimization cycles of design, synthesis and kinetic testing has lead to an effective inhibitor of Wip1, that is selective for this phosphatase over others. The picture shows the structure of the best inhibitor bound to the active site of the enzyme.
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Affiliation(s)
- Jeong Bang
- Laboratory of Cell Biology, NCI Bethesda, Maryland 20892
| | | | | | - Ettore Appella
- Laboratory of Cell Biology, NCI Bethesda, Maryland 20892
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616
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Abstract
SR proteins regulate alternative splicing by binding to exonic sequences where, via an arginine/serine-rich splicing activation domain, they enhance the binding of the spliceosome to the adjacent splice sites. Here, a system is described in which a nontoxic derivative of the small molecule rapamycin is used to control pre-mRNA splicing in vitro. This involves the rapamycin-dependent recruitment of a splicing activation domain located on one protein to a second protein bound to the pre-mRNA. These results provide a new approach to explore for regulating gene expression in vivo with small molecules by controlling pre-mRNA splicing.
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Affiliation(s)
- Brenton R Graveley
- Department of Genetics and Developmental Biology, University of Connecticut Health Center, 263 Farmington Avenue, Farmington, CT 06030, USA.
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