To construct a eukaryotic expression plasmid containing the luciferase reporter gene (Fluc) to quickly detect apoptosis. Four amino acids, Asp-Glu-Val-Asp (DEVD), the recognize motif of Caspase-3, were introduced into the middle of the Fluc-C and N fragment. Meanwhile, four amino acids, Asp-Glu-Val-Gly (DEVG), were selected as a negative control. Subsequently, the recombinant gene was cloned into the N and C terminal end of the split intein, and named as pFluc-DEVD and pFluc-DEVG. Then the plasmids were transfected into cells and renilla luciferase was co-transfected in each sample as an internal control for transfection efficiency. Then the apoptosis level was detected by the double luciferase reporter gene and the Western blotting analysis. The results showed that when apoptosis occurred, the content of firefly luciferase expressed in the pFluc-DEVD plasmid transfected group was about 3 times higher than pFluc-DEVG plasmid transfected group. Furthermore, Western blotting detection indicated that the Fluc level was significantly increased in pFluc-DEVD transfected group when pre-treated by apoptosis stimulants. The activation degree of Caspase-3 was closely related to the expression of Fluc, and had a significant statistical difference. These results confirmed that firefly luciferase protein expressed by pFluc-DEVD plasmid can be cleaved by the intracellular Caspase-3 enzyme, and this plasmid can accurately reflect the cell apoptosis level, which provides a useful method for quantitative detection of apoptosis.
Apoptosis ; Genes, Reporter ; Luciferases, Firefly ; Transfection

This study was aimed to construct, package and purify the recombinant lentivirus vector carrying the firefly luciferase gene (FLUC) and red fluorescent protein gene (RFP) and to transfect the recombinant lentivirus into HeLa cells, so as to observe the expression levels of these two genes. The FLUC and RFP genes were amplified by RT-PCR and inserted in the lentiviral expression vector (pLenti-Bi-cistronic) to construct the lentiviral vector pLenti-FLUC-RFP. The viral particles were generated by cotransfection of 293T cells with pLenti-FLUC-RFP and three packaging vectors, and the virus titer was determined by calculating the percentage of RFP positive cells. After transfection of pLenti-FLUC-RFP into HeLa cells, the expression of RFP was observed by fluorescent microscopy, and the activity of FLUC was determined by luciferase reporter gene assay kit. The results showed that the inserting orientation of the RFP and FLUC genes in the lentiviral vector pLenti-FLUC-RFP were verified by restriction analysis. Targeted RFP and FLUC sequences were confirmed by DNA sequencing. The final titer obtained was 1×10(7)TU/ml. The expressions of RFP and FLUC were observed in the transfected HeLa cells. It is concluded that the pLenti-III-FLUC-RFP recombinant lentivirus vector carrying RFP gene and FLUC gene with high viral titer is constructed and packaged successfully, and provides experimental basis for studying dynamic distribution of mesenchymal stem cells in vivo.
Gene Expression ; Genes, Reporter ; Genetic Vectors ; HeLa Cells ; Humans ; Lentivirus ; genetics ; Luciferases, Firefly ; genetics ; Luminescent Proteins ; genetics ; Transfection

The DNA segment of the human acyl coenzyme A: cholesterol acyltransferasel (ACAT1) gene P7 promoter was amplified by PCR from human monocytic leukemia cell line (THP-1) and cloned to TA vector, then the positive clone was confirmed by restriction enzymes and sequencing. The targeted segment was subcloned to Firefly luciferase report vector pGL3-Enhancer. The recombinant plasmid pGL3E-P7 was transfected transiently into THP-1, then the expression of luciferase could be detected in THP-1 by pGL3E-P7 transfection. We successfully constructed luciferase reporter vector containing P7 promoter of the human ACAT1 gene, and established a new means to study the transcriptional regulation mechanisms of ACAT1 during atherosclerosis.
Cell Line, Tumor ; Chromosomes, Human, Pair 7 ; genetics ; Gene Expression Regulation ; Genes, Reporter ; genetics ; Genetic Vectors ; genetics ; Humans ; Leukemia, Monocytic, Acute ; pathology ; Luciferases, Firefly ; genetics ; metabolism ; RNA, Messenger ; genetics ; metabolism ; Recombinant Proteins ; genetics ; metabolism ; Sterol O-Acyltransferase ; genetics ; metabolism ; Transfection

OBJECTIVETo generate a sensitive tool for noninvasive monitoring of a therapeutic gene vasostatin.

METHODSWe fused the bioluminescent reporter gene firefly luciferase to the therapeutic transgene vasostatin and ensured that these two proteins would not interrupt each other and kept their own natural character.

RESULTSWe therefore examined clones of PC3 cells stably expressing fusion gene and positive controlfluc with bioluminescence. In vivo imaging of PC3-Fluc subcutaneous tumors showed that the mean tumor bioluminescence increased in animals over several weeks.

CONCLUSIONNoninvasive monitoring facilitates the detection of gene expression in vivo and in vitro.

Animals ; Calreticulin ; genetics ; metabolism ; Cell Line, Tumor ; Gene Transfer Techniques ; Genes, Reporter ; Humans ; Luciferases, Firefly ; genetics ; metabolism ; Luminescent Measurements ; Neoplasm Transplantation ; Peptide Fragments ; genetics ; metabolism ; Recombinant Fusion Proteins ; genetics ; metabolism

We established an orthotopic non-muscle invasive bladder cancer (NMIBC) mouse model expressing the mammalian target of the rapamycin (mTOR) signaling pathway. After intravesical instillation of KU-7-lucs (day 0), animals were subsequently monitored by bioluminescence imaging (BLI) on days 4, 7, 14, and 21, and performed histopathological examination. We also validated the orthotopic mouse model expressing the mTOR signaling pathway immunohistochemically. In vitro BLI photon density was correlated with KU-7-luc cell number (r2 = 0.97, P < 0.01) and in vivo BLI photon densities increased steadily with time after intravesical instillation. The tumor take rate was 84.2%, formed initially on day 4 and remained NMIBC up to day 21. T1 photon densities were significantly higher than Ta (P < 0.01), and histological tumor volume was positively correlated with BLI photon density (r2 = 0.87, P < 0.01). The mTOR signaling pathway-related proteins were expressed in the bladder, and were correlated with the western blot results. Our results suggest successful establishment of an orthotopic mouse NMIBC model expressing the mTOR signaling pathway using KU-7-luc cells. This model is expected to be helpful to evaluate preclinical testing of intravesical therapy based on the mTOR signaling pathway against NMIBC.
Animals ; Blotting, Western ; Cell Line, Tumor ; Disease Models, Animal ; Female ; Genes, Reporter ; Green Fluorescent Proteins/genetics/metabolism ; Humans ; Immunohistochemistry ; Luciferases, Firefly/genetics ; Luminescent Measurements ; Mice ; Mice, Nude ; Neoplasm Staging ; *Signal Transduction ; TOR Serine-Threonine Kinases/*metabolism ; Transplantation, Heterologous ; Urinary Bladder Neoplasms/*metabolism/pathology/veterinary

Relative deficiency in production of glycoprotein hormone erythropoietin (Epo) is a major cause of renal anemia. This study planned to investigate whether the hypoxia-regulated system of Epo expression, constructed by fusing Epo gene to the chimeric phosphoglycerate kinase (PGK) hypoxia response elements (HRE) in combination with cytomegalovirus immediate-early (CMV IE) basal gene promoter and delivered by plasmid intramuscular injection, might provide a long-term physiologically regulated Epo secretion expression to correct the anemia in adenine-induced uremic rats. Plasmid vectors (pHRE-Epo) were synthesized by fusing human Epo cDNA to the HRE/CMV promoter. Hypoxia-inducible activity of this promoter was evaluated first in vitro and then in vivo in healthy and uremic rats (n = 30 per group). The vectors (pCMV-Epo) in which Epo expression was directed by a constitutive CMV gene promoter served as control. ANOVA and Student's t-test were used to analyze between-group differences. A high-level expression of Epo was induced by hypoxia in vitro and in vivo. Though both pHRE-Epo and pCMV-Epo corrected anemia, the hematocrit of the pCMV-Epo-treated rats exceeded the normal (P < 0.05), but that of the pHRE-Epo-treated rats didn't. Hypoxia-regulated system of Epo gene expression constructed by fusing Epo to the HRE/CMV promoter and delivered by plasmid intramuscular injection may provide a long-term and stable Epo expression and secretion in vivo to correct the anemia in adenine-induced uremic rats.
Anemia/blood/*therapy ; Animals ; Base Sequence ; Blood Urea Nitrogen ; Cell Hypoxia ; Creatinine/blood ; Erythropoietin/biosynthesis/*genetics/secretion ; Gene Expression Regulation ; Genes, Reporter ; Genetic Therapy ; HeLa Cells ; Humans ; Injections, Intramuscular ; Kidney/pathology ; Luciferases, Firefly/biosynthesis/genetics ; Molecular Sequence Data ; Plasmids/*genetics ; Promoter Regions, Genetic ; Rats ; Rats, Sprague-Dawley ; Recombinant Proteins/biosynthesis/genetics/secretion ; Response Elements ; Transcriptional Activation ; Uremia/blood/*therapy