The luminous intensity of dark variant (S1) separated from photobacterium phosphoreum (A2) was 1/10,000 less than that of wild-type. Ethidium bromide (EB) (0.6 mg/L), Mytomycin C (MC, 0.05 mg/L), 2-amino fluorene (2-AF, 1.0 mg/L) all could strongly induce reversion mutation for S1 within 24 h and increase reversion ratio significantly. The results of experiments indicated that these revertants had stable genetic characteristic and the mutation may take place at gene levels. The mutagenesis to S1 caused by EB, MC and 2-AF was detected and it may be used as a new rapid, simple and sensitive method for gene toxicant monitoring.
*Chemiluminescent Measurements ; Ethidium/pharmacology ; Ethidium/toxicity ; Luciferases/biosynthesis ; Mitomycins/pharmacology ; Mitomycins/toxicity ; Mutagens ; Mutation/*drug effects ; Photobacterium/*genetics ; Toxicology/methods ; Transcription, Genetic/drug effects ; Variation (Genetics)

The luminous intensity of dark variant (S1) separated from photobacterium phosphoreum (A2) was 1/10,000 less than that of wild-type. Ethidium bromide (EB) (0.6 mg/L), Mytomycin C (MC, 0.05 mg/L), 2-amino fluorene (2-AF, 1.0 mg/L) all could strongly induce reversion mutation for S1 within 24 h and increase reversion ratio significantly. The results of experiments indicated that these revertants had stable genetic characteristic and the mutation may take place at gene levels. The mutagenesis to S1 caused by EB, MC and 2-AF was detected and it may be used as a new rapid, simple and sensitive method for gene toxicant monitoring.
Ethidium ; pharmacology ; toxicity ; Genetic Variation ; Luciferases ; biosynthesis ; Luminescent Measurements ; Mitomycins ; pharmacology ; toxicity ; Mutagens ; Mutation ; drug effects ; Photobacterium ; genetics ; Toxicology ; methods ; Transcription, Genetic ; drug effects

OBJECTIVE: To construct a luciferase reporter gene vector carrying human nuclear factor of activated T cells 2 (NFATc2) gene promoter and examine the effects of metformin and lipopolysaccharide (LPS) on the transcriptional activity of NFATc2 gene. METHODS: The promoter sequence of human NFATc2 gene was acquired from UCSC website for PCR amplification. NFATc2 promoter fragment was inserted into pGL3-basic plasmid double cleaved with Kpn Ⅰ and Hind Ⅲ. The resultant recombinant plasmid pGL3-NFATC2-promoter was co-transfected with the internal reference plasmid pRL-TK in 293F cells, and luciferase activity in the cells was detected. Reporter gene vectors of human NFATc2 gene promoter with different fragment lengths were also constructed and assayed for luciferase activity. The changes in transcription activity of NFATc2 gene were assessed after treatment with different concentrations of metformin and LPS for 24 h. We also examined the effect of mutation in RUNX2-binding site in NFATC2 gene promoter on the regulatory effects of metformin and LPS on NFATc2 transcription. RESULTS: We successfully constructed pGL3-NFATc2-promoter plasmids carrying different lengths (2170 bp, 2077 bp, 1802 bp, 1651 bp, 1083 bp, 323 bp) of NFATc2 promoter sequences as verified by enzymatic digestion and sequencing. Transfection of 293F cells with the plasmid carrying a 1651 bp NFATc2 promoter (pGL3-1651 bp) resulted in the highest transcriptional activity of NFATc2 gene, and the luciferase activity was approximately 3.3 times that of pGL3-2170 bp (1.843 ± 0.146 vs 0.547 ± 0.085). Moderate (5 mmol/L) and high (10 mmol/L) concentrations of metformin significantly upregulated the transcriptional activity of pGL3-1651 bp by up to 2.5 and 3 folds, respectively. LPS at different doses also upregulated the transcriptional activity of pGL3-1651 bp by at least 1.6 folds. The mutation in the RUNX2 binding site on pGL3-1651 bp obviously reduced metformin- and LPS-induced enhancement of pGL3-1651bp transcription by 1.7 and 2 folds, respectively. CONCLUSION pGL3-NFATc2-promoter can be transcribed and activated in 293F cells, and LPS and metformin can activate the transcription of pGL3- NFATc2-promoter in a RUNX2-dependent manner.
Core Binding Factor Alpha 1 Subunit/genetics* ; Humans ; Lipopolysaccharides/pharmacology* ; Luciferases/genetics* ; Metformin/pharmacology* ; NFATC Transcription Factors/genetics* ; Promoter Regions, Genetic ; T-Lymphocytes ; Transcription, Genetic/drug effects* ; Transfection

Influenza virus RNA-dependent RNA polymerase (RdRP) is essential for replication and expression of influenza virus genome. Viral genomic sequences encoding RdRP are highly conservative, thus making it a potential anti-influenza drug target. A cell-based influenza RdRP inhibitor screening assay was established by a luciferase reporter system to analyze the activity of RdRP. Specificity study and statistic analysis showed that the screening assay is sensitive and reproducible.
Amantadine ; pharmacology ; Antiviral Agents ; isolation & purification ; pharmacology ; Drug Evaluation, Preclinical ; methods ; Genes, Reporter ; HEK293 Cells ; Humans ; Influenzavirus A ; enzymology ; Luciferases ; genetics ; metabolism ; Oseltamivir ; pharmacology ; Plasmids ; RNA Replicase ; antagonists & inhibitors ; metabolism ; Reproducibility of Results ; Ribavirin ; pharmacology ; Sensitivity and Specificity ; Transfection ; Zanamivir ; pharmacology

OBJECTIVETo investigate the inhibitory activity of HIF-1 by triptolide and manasaantin A, two cell-based models with luciferase report gene assay were established.

METHODTwo cell-based models of HIF-1 were used to evaluate HIF-1 inhibition activity of triptolide and manasaantin A. Secreted VEGF expression induced by hypoxia was detected by ELISA with two compounds. The growth inhibition of different solid tumor cell lines was measured by the MTT assay.

RESULTThe expression of firefly luciferase was induced by hypoxia in U251-HRE and T47D-HRE cells. U251-HRE model was suitable for the detection of HIF-1 inhibition activity of triptolide. The IC50 of triptolide on HIF-1 activity was (3.4 +/- 0.5) x 10(-8) mol x L(-1). The report gene assay using T47D cells co-transfected with pGL2-TK-HRE and pRL-CMV showed more sensitive inhibition activity of HIF-1 on manassantin A than that of detected by U251-HRE model. The IC50 of manassantin A on HIF-1 activity was (2.4 +/- 0.6) x 10(-8) mol x L(-1). HIF-1 target gene VEGF was also inhibited by test compounds on protein level in T47D cells. Manasaantin A showed selective inhibition on the growth of human solid cancer cell lines, especially on breast cancer and pancreatic cancer cells. Meanwhile, triplotide showed strong proliferation inhibition activity on all tested cell lines.

CONCLUSIONIt is very important to select a suitable cell-based report gene assay of HIF-1 for screening of different kinds of inhibitor.

Cell Line, Tumor ; Cell Proliferation ; drug effects ; Diterpenes ; pharmacology ; Drug Evaluation, Preclinical ; methods ; Epoxy Compounds ; pharmacology ; Humans ; Hypoxia-Inducible Factor 1 ; antagonists & inhibitors ; Lignans ; pharmacology ; Luciferases ; genetics ; Models, Biological ; Neoplasms ; drug therapy ; pathology ; Phenanthrenes ; pharmacology

To establish a cell-based rapid luciferase suppression assay for high-throughput screening (HTS) anti-alphaviruses compounds screening, which could cause viral encephalitis, raise the social issues associated directly with public health and huge economic burden to the society. The Gaussia luciferase assay system was used for HTS model for identifying inhibitors of labeled virus XJ160-GLUC. The decreased 50% GLUC activity inhibition ratio was deemed to be the screening positive index. The reaction system in this model was optimized, and the reliability of the model was evaluated. For HTS model's optimization, cells were infected with XJ160-GLUC at an MOI of 0.025 PFU/cell. The supernatant treated with compounds 48h were collected for GLUC expression detection. In the model, Z' factor was up to 0.71, demonstrating that HTS assay for identifying inhibitors that target all aspects of the viral life cycle of XJ160-GLUC was stable and reliable. After screening 8080 compounds (five-in-one), 341 positive samples were selected, and the positive rate was 4.2% with a cutoff at 50% inhibition. Then 1705 compounds were screened subsequently and the positive rate was 1.1% with obtaining 19 positive compounds. These results will lay the foundation for finding the anti-alphaviruses' drug targets.
Alphavirus ; drug effects ; genetics ; metabolism ; Animals ; Antiviral Agents ; pharmacology ; Drug Evaluation, Preclinical ; methods ; Genes, Reporter ; High-Throughput Screening Assays ; methods ; Luciferases ; genetics ; metabolism

Ebola virus, the cause of severe and fatal hemorrahagic fever in humans, belongs to filovirus family. This study was designed to establish a cell-based screening and evaluation system in the pharmacological study of antivirus compounds. Three reporter systems were established with recombinant pseudoviral luciferase of HIV core (pNL4-3.Luc.R(-)E(-)) packed with filovirus glycoprotein (EBOV-Zaire GP/HIV-luc, EBOV-Sudan GP/HIV-luc and Marburg GP/HIV-luc), which are required for virus entry of cells. The level of filovirus entry was determined by the expression of luciferase reporter gene in the infected cells. For screening of filovirus entry inhibitors, the vesicular stomatitis G packed pseudovirions (VSVG/HIV-luc) was used to determine the compound specificity. The results of known filovirus entry inhibitors demonstrated successful establishment of the new model systems, which would be useful in high throughput screening of anti-filovirus drugs in the future.
Antiviral Agents ; pharmacology ; Drug Evaluation, Preclinical ; methods ; Ebolavirus ; drug effects ; physiology ; Genes, Reporter ; Glycoproteins ; genetics ; Hemorrhagic Fever, Ebola ; Humans ; Luciferases ; Viral Proteins ; genetics ; Virus Internalization ; drug effects

BACKGROUND: Steroid receptor-associated and regulated protein (SRARP) suppresses tumor progression and modulates steroid receptor signaling by interacting with estrogen receptors and androgen receptors in breast cancer. In endometrial cancer (EC), progesterone receptor (PR) signaling is crucial for responsiveness to progestin therapy. The aim of this study was to investigate the role of SRARP in tumor progression and PR signaling in EC. METHODS: Ribonucleic acid sequencing data from the Cancer Genome Atlas, Clinical Proteomic Tumor Analysis Consortium, and Gene Expression Omnibus were used to analyze the clinical significance of SRARP and its correlation with PR expression in EC. The correlation between SRARP and PR expression was validated in EC samples obtained from Peking University People's Hospital. SRARP function was investigated by lentivirus-mediated overexpression in Ishikawa and HEC-50B cells. Cell Counting Kit-8 assays, cell cycle analyses, wound healing assays, and Transwell assays were used to evaluate cell proliferation, migration, and invasion. Western blotting and quantitative real-time polymerase chain reaction were used to evaluate gene expression. The effects of SRARP on the regulation of PR signaling were determined by co-immunoprecipitation, PR response element (PRE) luciferase reporter assay, and PR downstream gene detection. RESULTS: Higher SRARP expression was significantly associated with better overall survival and disease-free survival and less aggressive EC types. SRARP overexpression suppressed growth, migration, and invasion in EC cells, increased E-cadherin expression, and decreased N-cadherin and Wnt family member 7A ( WNT7A ) expression. SRARP expression was positively correlated with PR expression in EC tissues. In SRARP -overexpressing cells, PR isoform B (PRB) was upregulated and SRARP bound to PRB. Significant increases in PRE-based luciferase activity and expression levels of PR target genes were observed in response to medroxyprogesterone acetate. CONCLUSIONS This study illustrates that SRARP exerts a tumor-suppressive effect by inhibiting the epithelial-mesenchymal transition via Wnt signaling in EC. In addition, SRARP positively modulates PR expression and interacts with PR to regulate PR downstream target genes.
Female ; Humans ; Receptors, Progesterone/metabolism* ; Proteomics ; Cell Line, Tumor ; Endometrial Neoplasms/metabolism* ; Cell Proliferation/genetics* ; Luciferases/pharmacology* ; Gene Expression Regulation, Neoplastic/genetics*

This study aimed to analyze the effect of matrine on tumor necrosis factor-α(TNF-α)-induced inflammatory response in human umbilical vein endothelial cells(HUVECs) and explore whether the underlying mechanism was related to the miR-25-3p-mediated Krüppel-like factor 4(Klf4) pathway. The HUVEC cell inflammation model was induced by TNF-α stimulation. After 24 or 48 hours of incubation with different concentrations of matrine(0.625, 1.25, and 2.5 mmol·L~(-1)), CCK-8 assay was used to detect cell proliferation. After treatment with 2.5 mmol·L~(-1) matrine for 48 h, the expression of TNF-α, interleukin-6(IL-6), interleukin-1β(IL-1β), and Klf4 mRNA and miR-25-3p was detected by real-time fluorescence-based quantitative PCR, and the protein expression of TNF-α, IL-6, IL-1β, and Klf4 was detected by Western blot. The anti-miR-25-3p was transfected into HUVECs, and the effect of anti-miR-25-3p on TNF-α-induced cell proliferation and inflammatory factors was detected by the above method. The cells were further transfected with miR-25-3p and incubated with matrine to detect the changes in proliferation and expression of related inflammatory factors, miR-25-3p, and Klf4. The targeting relationship between miR-25-3p and Klf4 was verified by bioinformatics analysis and dual luciferase reporter gene assay. The results displayed that matrine could inhibit TNF-α-induced HUVEC proliferation, decrease the mRNA and protein expression of TNF-α, IL-6, and IL-1β, increase the mRNA and protein expression of Klf4, and reduce the expression of miR-25-3p. Bioinformatics analysis showed that there were specific complementary binding sites between miR-25-3p and Klf4 sequences. Dual luciferase reporter gene assay confirmed that miR-25-3p negatively regulated Klf4 expression in HUVECs by targeting. The inhibition of miR-25-3p expression can reduce TNF-α-induced cell proliferation and mRNA and protein expression of TNF-α, IL-6, and IL-1β. MiR-25-3p overexpression could reverse the effect of matrine on TNF-α-induced cell proliferation and the mRNA and protein expression of TNF-α, IL-6, IL-1β, and Klf4. This study shows that matrine inhibits the inflammatory response induced by TNF-α in HUVECs through miR-25-3p-mediated Klf4 pathway.
Humans ; Tumor Necrosis Factor-alpha/metabolism* ; MicroRNAs/metabolism* ; Human Umbilical Vein Endothelial Cells ; Matrines ; Interleukin-6/genetics* ; Signal Transduction ; Antagomirs ; Inflammation/metabolism* ; Luciferases/pharmacology* ; RNA, Messenger ; Apoptosis

Leishmaniasis is a worldwide uncontrolled parasitic disease due to the lack of effective drug and vaccine. To speed up effective drug development, we need powerful methods to rapidly assess drug effectiveness against the intracellular form of Leishmania in high throughput assays. Reporter gene technology has proven to be an excellent tool for drug screening in vitro. The effects of reporter proteins on parasite infectivity should be identified both in vitro and in vivo. In this research, we initially compared the infectivity rate of recombinant Leishmania major expressing stably enhanced green fluorescent protein (EGFP) alone or EGFP-luciferase (EGFP-LUC) with the wild-type strain. Next, we evaluated the sensitivity of these parasites to amphotericin B (AmB) as a standard drug in 2 parasitic phases, promastigote and amastigote. This comparison was made by MTT and nitric oxide (NO) assay and by quantifying the specific signals derived from reporter genes like EGFP intensity and luciferase activity. To study the amastigote form, both B10R and THP-1 macrophage cell lines were infected in the stationary phase and were exposed to AmB at different time points. Our results clearly revealed that the 3 parasite lines had similar in vitro infectivity rates with comparable parasite-induced levels of NO following interferon-gamma/lipopolysaccharide induction. Based on our results we proposed the more reporter gene, the faster and more sensitive evaluation of the drug efficiency.
Amphotericin B/*pharmacology ; Animals ; Antiprotozoal Agents/*pharmacology ; Drug Evaluation, Preclinical/instrumentation/*methods ; Female ; Gene Expression ; Genes, Reporter ; Green Fluorescent Proteins/genetics/*metabolism ; Humans ; Leishmania major/*drug effects/genetics/growth & development/physiology ; Leishmaniasis, Cutaneous/*parasitology ; Luciferases/genetics/*metabolism ; Mice