Identification of Novel Compounds Enhancing SR-BI mRNA Stability through High-Throughput Screening

2019 ◽  
Vol 25 (4) ◽  
pp. 397-408
Author(s):  
Xiao-Jian Jia ◽  
Yu Du ◽  
Hua-Jun Jiang ◽  
Yong-Zhen Li ◽  
Yan-Ni Xu ◽  
...  
Keyword(s):  
Cardiovascular Diseases ◽  
High Throughput ◽  
Mrna Stability ◽  
High Throughput Screening ◽  
Cholesterol Homeostasis ◽  
Luciferase Reporter ◽  
Regulation Mechanism ◽  
Dependent Manner ◽  
Luciferase Reporter Gene ◽  
Relationship Analysis

Atherosclerosis is the pathological basis of most cardiovascular diseases. Reverse cholesterol transport (RCT) is a main mechanism of cholesterol homeostasis and involves the direct transport of high-density lipoprotein (HDL) cholesteryl ester by selective cholesterol uptake. Hepatic scavenger receptor class B member 1 (SR-BI) overexpression can effectively promote RCT and reduce atherosclerosis. SR-BI may be an important target for prevention or treatment of atherosclerotic disease. In our study, we inserted human SR-BI mRNA 3′ untranslated region (3′UTR) downstream of the luciferase reporter gene, to establish a high-throughput screening model based on stably transfected HepG2 cells and to screen small-molecule compounds that can significantly enhance the mRNA stability of the SR-BI gene. Through multiple screenings of 25 755 compounds, the top five active compounds that have similar structures were obtained, with a positive rate of 0.19%. The five positive compounds could enhance the SR-BI expression and uptake of DiI-HDL in the hepatocyte HepG2. E238B-63 could also effectively extend the half-life of SR-BI mRNA and enhance the SR-BI mRNA and protein level and the uptake of DiI-HDL in hepatocytes in a time-dependent and dose-dependent manner. The structure-activity relationship analysis showed that the structure N-(3-hydroxy-2-pyridyl) carboxamide is possibly the key pharmacophore of the active compound, providing reference for acquiring candidate compounds with better activity. The positive small molecular compounds obtained in this study might become new drug candidates or lead compounds for the treatment of cardiovascular diseases and contribute to the further study of the posttranscriptional regulation mechanism of the SR-BI gene.

scholarly journals Novel Whole-Cell Antibiotic Biosensors for Compound Discovery

2007 ◽  
Vol 73 (20) ◽  
pp. 6436-6443 ◽  
Author(s):  
Andreas Urban ◽  
Stefan Eckermann ◽  
Beate Fast ◽  
Susanne Metzger ◽  
Matthias Gehling ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
High Throughput ◽  
High Throughput Screening ◽  
Protein Biosynthesis ◽  
Firefly Luciferase ◽  
Luciferase Reporter ◽  
Luciferase Reporter Gene ◽  
Environmental Biology ◽  
Drug Candidates ◽  
Novel Drug

ABSTRACT Cells containing reporters which are specifically induced via selected promoters are used in pharmaceutical drug discovery and in environmental biology. They are used in screening for novel drug candidates and in the detection of bioactive compounds in environmental samples. In this study, we generated and validated a set of five Bacillus subtilis promoters fused to the firefly luciferase reporter gene suitable for cell-based screening, enabling the as yet most-comprehensive high-throughput diagnosis of antibiotic interference in the major biosynthetic pathways of bacteria: the biosynthesis of DNA by the yorB promoter, of RNA by the yvgS promoter, of proteins by the yheI promoter, of the cell wall by the ypuA promoter, and of fatty acids by the fabHB promoter. The reporter cells mainly represent novel antibiotic biosensors compatible with high-throughput screening. We validated the strains by developing screens with a set of 14,000 pure natural products, representing a source of highly diverse chemical entities, many of them with antibiotic activity (6% with anti-Bacillus subtilis activity of ≤25 μg/ml]). Our screening approach is exemplified by the discovery of classical and novel DNA synthesis and translation inhibitors. For instance, we show that the mechanistically underexplored antibiotic ferrimycin A1 selectively inhibits protein biosynthesis.

scholarly journals Use of Leishmania donovani Field Isolates Expressing the Luciferase Reporter Gene in In Vitro Drug Screening

2005 ◽  
Vol 49 (9) ◽  
pp. 3776-3783 ◽  
Author(s):  
Ashutosh ◽  
Suman Gupta ◽  
Ramesh ◽  
Shyam Sundar ◽  
Neena Goyal
Keyword(s):  
Reporter Gene ◽  
High Throughput ◽  
High Throughput Screening ◽  
Leishmania Donovani ◽  
Luciferase Activity ◽  
Firefly Luciferase ◽  
Luciferase Reporter ◽  
Luciferase Reporter Gene ◽  
Field Isolates

ABSTRACT Currently available primary screens for the selection of candidate antileishmanial compounds are not ideal. These techniques are time-consuming, laborious, and difficult to scale and require macrophages, which limit their use for high-throughput screening. We have developed Leishmania donovani field isolates that constitutively express the firefly luciferase reporter gene (luc) as a part of an episomal vector. An excellent correlation between parasite number and luciferase activity was observed. luc expression was stable, even in the absence of drug selection, for 4 weeks. The transfectants were infective to macrophages, and intracellular amastigotes exhibited luciferase activity. The suitability of these recombinant field isolates for in vitro screening of antileishmanial drugs was established. The luciferase-expressing sodium stibogluconate-resistant cell lines offer a model for the screening of compounds for resistance. The system is in routine use at the Central Drug Research Institute, Lucknow, India, for high-throughput screening of newly synthesized compounds.

scholarly journals Luciferase Measurements in High Throughput Screening

1996 ◽  
Vol 1 (2) ◽  
pp. 85-88 ◽  
Author(s):  
Alfred J. Kolb ◽  
Kenneth Neumann
Keyword(s):  
Reporter Gene ◽  
High Throughput ◽  
High Throughput Screening ◽  
Culture Media ◽  
Luciferase Assay ◽  
Luciferase Reporter ◽  
Luciferase Reporter Gene ◽  
Cell Culture Media ◽  
Luminescence Signal ◽  
Temperature Controlled

Luminescence assays are becoming more popular in high throughput screening (HTS) laboratories with the luciferase reporter gene being the most common. As with other assays that are adapted to HTS, improvements have been made to the luciferase assay to make it better suited to the requirements of HTS. For the luciferase reporter gene, these improvements included stabilization of the enzyme, increasing the half-life of the luminescence signal to 5 h, and eliminating separation steps (centrifugation and aliquot transfer) after cell lysis. The improved assay, LucLite, is homogeneous and is measured directly in the cell culture media. In addition to reagent improvements, a temperature-controlled, multidetector microplate counter, TopCount, can quickly and accurately measure luminescence signals.

scholarly journals Novel Chimeric Genotype 1b/2a Hepatitis C Virus Suitable for High-Throughput Screening

2007 ◽  
Vol 52 (2) ◽  
pp. 666-674 ◽  
Author(s):  
Yingjia Zhang ◽  
Peter Weady ◽  
Rohit Duggal ◽  
Weidong Hao
Keyword(s):  
Hepatitis C Virus ◽  
Hepatitis C ◽  
High Throughput ◽  
High Throughput Screening ◽  
Luciferase Reporter ◽  
Structural Protein ◽  
Genotype 1 ◽  
Luciferase Reporter Gene ◽  
Subgenomic Replicon ◽  
Viral Particles

ABSTRACT A major obstacle in hepatitis C virus (HCV) research has been the lack of a permissive cell culture system that produces infectious viral particles. Significant breakthroughs have been achieved lately in establishing such culture systems. Yet to date, there are no reports of the applications of any of these systems in HCV drug screening. Here, we report the generation of two monocistronic, chimeric genotype 1 full-length HCV genome molecules. These molecules, C33J-Y835C-UBI and C33J-Y835C-FMDV2A, both contain the structural protein region from genotype 1 (subtype 1b, Con1) and the remaining region from the genotype 2a (JFH1) clone. Both contain the humanized Renilla luciferase reporter gene which is separated from the rest of the HCV open reading frame by two different cleavage sites. The viral RNAs replicated efficiently in transfected cells. Viral particles produced were infectious in naïve Huh7.5 cells, and the infectivity could be blocked by monoclonal antibody against a putative HCV entry cofactor, CD81. A pilot high-throughput screen of 900 unknown compounds was executed by both the genotype 2a subgenomic replicon system and the infectious system. Thirty-one compounds were identified as hits by both systems, whereas 78 compounds were identified as hits only for the infectious system, suggesting that the infectious system is capable of identifying inhibitors targeting the viral structural proteins and steps involving them in the viral life cycle. The infectious HCV system developed here provides a useful and versatile tool which should greatly facilitate the identification of HCV inhibitors currently not identified by the subgenomic replicon system.

Optimization of a High-Throughput Cell-Based Screening Strategy to Identify Small-Molecule Inhibitors of IL-23 Signaling

2020 ◽  
Vol 26 (1) ◽  
pp. 122-129
Author(s):  
Teena M. Varghese ◽  
Paul L. Dudas ◽  
Samantha J. Allen ◽  
Jonathan E. Schneeweis ◽  
Michael F. A. Finley
Keyword(s):  
Small Molecule ◽  
High Throughput ◽  
High Throughput Screening ◽  
Small Molecule Inhibitors ◽  
Screening Strategy ◽  
Luciferase Reporter ◽  
Luciferase Reporter Gene ◽  
Screening Assay ◽  
Gene Assay ◽  
Ifn Γ

Interleukin-23 (IL-23) is a key cytokine implicated in the pathogenesis of autoimmune disorders, including psoriasis and ulcerative colitis. Although targeted IL-23 antibody therapeutics are used clinically, there are no small-molecule therapeutics that selectively inhibit IL-23 signaling. To address this gap, we developed a high-throughput screening strategy employing an IL-23-responsive cell-based luciferase reporter gene assay as the primary screen, with cellular cytotoxicity and off-target counter screening assays to identify IL-23 pathway-specific inhibitors. The primary screening assay utilized avian DT40 cells, genetically engineered to overexpress IL-23R, IL-12Rβ1, STAT5, and firefly luciferase, in a 1536-well format. Treatment of these cells with IL-23 resulted in the phosphorylation and activation of STAT5, which was completely inhibited by the pan-JAK inhibitor tofacitinib. Assay performance was robust, with signal-to-background >7-fold and Z′ > 0.5 over 40 screening plates (approximately 24,000 compounds), with a hit rate of 5% (>66.9% activity cutoff). Of these 1288 hits, 66% were identified as cytotoxic by incubating the IL-23 reporter cells with compound overnight and measuring cell viability. Further assessment of specificity via examination of impact on off-target IFN-γ signaling eliminated an additional 230 compounds, leaving 209 that were evaluated for dose–response activity. Of these compounds, 24 exhibited IC50 values of <7 µM and ≥80% inhibition of IL-23 activity, with >3-fold selectivity over IFN-γ inhibition, thus representing promising starting points for prospective IL-23 pathway small-molecule inhibitors.

scholarly journals Sevoflurane inhibits proliferation, invasion, but enhances apoptosis of lung cancer cells by Wnt/β-catenin signaling via regulating lncRNA PCAT6/ miR-326 axis

2020 ◽  
Vol 15 (1) ◽  
pp. 159-172
Author(s):  
Guoning Su ◽  
Zhibing Yan ◽  
Min Deng
Keyword(s):  
Lung Cancer ◽  
Cancer Cells ◽  
Volatile Anesthetic ◽  
Lung Cancer Cells ◽  
Luciferase Reporter ◽  
Dependent Manner ◽  
Luciferase Reporter Gene ◽  
Western Blot Assay ◽  
Gene Assay ◽  
Cancer Tissues

AbstractSevoflurane was frequently used as a volatile anesthetic in cancer surgery. However, the potential mechanism of sevoflurane on lung cancer remains largely unclear. In this study, lung cancer cell lines (H446 and H1975) were treated by various concentrations of sevoflurane. 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assessment and colony formation assay were performed to detect the cell viability and proliferation, separately. Also, transwell assay or flow cytometry assay was applied as well to evaluate the invasive ability or apoptosis in lung cancer cells, respectively. Western blot assay was employed to detect the protein levels of β-catenin and Wnt5a. Moreover, quantitative real-time polymerase chain reaction (qRT-PCR) was used to examine the expression level of prostate cancer-associated transcript 6 (PCAT6) and miR-326 in lung cancer tissues and cells. The target interaction between miR-326 and PCAT6 or Wnt5a was predicted by bioinformatics analysis and verified by the dual-luciferase reporter gene assay. Sevoflurane inhibited the abilities on viability, proliferation, invasion, and activation of Wnt/β-catenin signaling, but promoted apoptosis of H446 and H1975 cells in a dose-dependent manner. The expression of PCAT6 was increased in lung cancer tissues and cells, except for that of miR-326. Besides, sevoflurane could lead to expressed limitation of PCAT6 or improvement of miR-326. This process presented a stepwise manner. Up-regulation of PCAT6 restored the suppression of sevoflurane on abilities of proliferation, invasion, rather than apoptosis, and re-activated the Wnt5a/β-catenin signaling in cells. Moreover, the putative binding sites between miR-326 and PCTA6 or Wnt5a were predicted by starBase v2.0 software online. PCAT6 suppressing effects on cells could be reversed by pre-treatment with miR-326 vector. The promotion of Wnt5a inverted effects led from miR-326 or sevoflurane. Our study indicated that sevoflurane inhibited the proliferation, and invasion, but enhanced the apoptosis in lung cancer cells by regulating the lncRNA PCAT6/miR-326/Wnt5a/β-catenin axis.

scholarly journals Affordable Luciferase Reporter Assay for Cell-Based High-Throughput Screening

2012 ◽  
Vol 18 (4) ◽  
pp. 453-461 ◽  
Author(s):  
Ellen Siebring-van Olst ◽  
Christie Vermeulen ◽  
Renee X. de Menezes ◽  
Michael Howell ◽  
Egbert F. Smit ◽  
...  
Keyword(s):  
High Throughput ◽  
High Throughput Screening ◽  
Firefly Luciferase ◽  
Luciferase Assay ◽  
Luciferase Reporter ◽  
Chemical Components ◽  
Simple Liquid ◽  
Luciferase Reporter Construct ◽  
Reagent Cost ◽  
Firefly Luciferase Gene

The firefly luciferase gene is commonly used in cell-based reporter assays. Convenient luciferase assay reagents for use in high-throughput screening (HTS) are commercially available. However, the high cost of these reagents is not within the means of some academic laboratories. Therefore, we set out to develop an affordable luciferase assay reagent applicable in an HTS format using simple liquid-handling steps. The reagent was homemade from individual chemical components and optimized for luminescence intensity and stability. We determined the minimal concentrations of the most expensive components, dithiothreitol (DTT) and D-luciferin, resulting in a total assay reagent cost of less than 1 cent per sample. Signal stability was maximized by omission of coenzyme A and reduction of DTT concentration. The assay was validated in a high-throughput setting using two cancer cell lines carrying a p53-dependent luciferase reporter construct and siRNAs modulating p53 transcriptional activity. Induction of p53 activity by silencing PPM1D or SYVN1 and reduction of p53 activity by silencing p53 remained constant over a 2-h measurement period, with good assay quality (Z′ factors mostly above 0.5). Hence, the luciferase assay described herein can be used for affordable reporter readout in cell-based HTS.

scholarly journals Measurement of Effects of Antibiotics in Bioluminescent Staphylococcus aureus RN4220

2001 ◽  
Vol 45 (12) ◽  
pp. 3456-3461 ◽  
Author(s):  
Mervi Tenhami ◽  
Kaisa Hakkila ◽  
Matti Karp
Keyword(s):  
Staphylococcus Aureus ◽  
High Throughput Screening ◽  
Pathogenic Bacteria ◽  
Antimicrobial Agents ◽  
Light Emission ◽  
Detection System ◽  
Firefly Luciferase ◽  
Luciferase Reporter ◽  
Luciferase Expression ◽  
Luciferase Reporter Gene

ABSTRACT The spread of antibiotic resistance among pathogenic bacteria is a serious threat to humans and animals. Therefore, unnecessary use should be minimized, and new antimicrobial agents with novel mechanisms of action are needed. We have developed an efficient method for measuring the action of antibiotics which is applied to a gram-positive strain,Staphylococcus aureus RN4220. The method utilizes the firefly luciferase reporter gene coupled to the metal-induciblecadA promoter in a plasmid, pTOO24. Correctly timed induction by micromolar concentrations of antimonite rapidly triggers the luciferase gene transcription and translation. This sensitizes the detection system to the action of antibiotics, and especially for transcriptional and translational inhibitors. We show the results for 11 model antibiotics with the present approach and compare them to an analytical setup with a strain where luciferase expression is under the regulation of a constitutive promoter giving only a report of metabolic inhibition. The measurement of light emission from intact living cells is shown to correlate extremely well (r = 0.99) with the conventional overnight growth inhibition measurement. Four of the antibiotics were within a 20% concentration range and four were within a 60% concentration range of the drugs tested. This approach shortens the assay time needed, and it can be performed in 1 to 4 h, depending on the sensitivity needed. Furthermore, the assay can be automatized for high-throughput screening by the pharmaceutical industry.

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