Notes: The 3’ UTR of the human SNCA message was subcloned into the psiCHECK™-2 Vector and used to screen siRNAs for interaction. Results were determined through the use of the Dual-Luciferase® Reporter Assay System. Identified siRNA duplexes were transfected into human fibroblasts possessing SNCA locus triplication seeded into 6-well plates at 1 × 10⁵ cell/well using 10nM final concentration utilizing ViaFect™ Transfection Reagent. Twenty-fours hours after transfection, RNA was extracted and analyzed. [The authors judged transfection efficiency for ViaFect and these cells by transfecting a GFP expression plasmid and visualizing the GFP positive cells (results in Supplementary Figure S4)]. (4681)

Notes: This study identified that miR-21 is significantly overexpressed in human cervical squamous cancer tissues and cell lines, and showed that the level of miR-21 correlates with tumor differentiation, and regulates proliferation, apoptosis, and migration of HPV16-positive cells. The authors used gene expression profiling and luciferase reporter assay to identify candidate target genes for miR-21. Wildtype and mutant 3′-UTR sequences from the target gene CCL20 containing putative binding sites for miR-21 were subcloned into the psiCHECK-2 Vector and used to transfect HEK293 cells. The Dual-Luciferase® Reporter Assay System and GloMax® Multi Luminometer were used to measure luciferase activity from both constructs. (4192)

Notes: To confirm the role of a mutation in the miR-96 microRNA (miRNA) associated with an autosomal dominant hearing lost, HeLa cells (250,000 cells per well in six-well plates) were transfected with 4µg of plasmid carrying wild type or mutant miR-96 miRNA using FuGENE® HD Transfection Reagent. After 24 hours, the cells were washed and total RNA extracted. After quantitation, the RNA used in RT-PCR analysis. The entire 3´UTRs of eight putative target genes were amplified by PCR from genomic DNA and cloned into the psiCHECK™-2 Vector. HeLa cells were transiently transfected with 2µg of the 3´ UTR psiCHECK™-2 constructs and 0.2µg of a wild-type, single or double mutant miR-96 plasmid using FuGENE® HD Transfection Reagent. Forty-eight hours after transfection, the Dual-Luciferase® Reporter Assay System was used to quantify the firefly and Renilla luciferase in cell lysates. (4251)

Notes: The authors identified a single nucleotide polymorphism (SNP) in the 3´ untranslated region (3´ UTR) of MDM4, which promotes tumorigenesis by decreasing p53 tumor suppressor function, in ovarian cancer cells. This A to C transversion creates a putative target site for the hsa-miR-191 microRNA in the MDM4-C allele, but not the wildtype MDM4-A allele. To determine if this SNP affects MDM4 translation efficiency or mRNA stability, the authors cloned a 224-bp fragment of the MDM4 3´UTRs into the psiCHECK™-2 Vector and transfected the ovarian cancer cell line A2780 with the 224A or 224C variants of the MDM4 3´ UTR. The authors used the luciferase-based psiCHECK™-2 Vector and Dual-Glo^® Luciferase Assay System to show that the C variant dramatically reduces translation efficiency and/or mRNA stability. They also assessed MDM4 expression levels in A/A, A/C and C/C ovarian cancer cells and tissues using RT-qPCR. qPCR primers for MDM4 were designed using the Plexor^® Primer Design Software, and assays were performed using the Plexor^® qPCR System. (4157)

Notes: The authors explored the role of five different eukaryotic initiation factor (eIF) 4GI protein isoforms, which are encoded by alternatively spliced mRNAs, by using short interfering RNAs (siRNAs) to silence the eIF4GI gene. Three eIF4GI siRNA target sequences were evaluated for their ability to reduce eIF4GI mRNA levels in HeLa cells. To quantify the extent of gene silencing, a control plasmid that encodes an eIF4GI/Renilla luciferase fusion mRNA was created using the psiCHECK™-2 Vector. Cotransfection of HeLa cells with the eIF4GI siRNAs and psiCHECK™-2 control plasmid resulted in degradation of the eIF4GI/Renilla luciferase mRNA, leading to reduced Renilla luciferase activity and lower light output. The psiCHECK™-2 Vector encodes the firefly luciferase gene, which allowed normalization of Renilla luciferase expression. Firefly and Renilla luciferase activities were measured using the Dual-Luciferase^® Reporter Assay System. Quantitative PCR (qPCR) was used to quantify the silencing of endogenous eIF4GI mRNA splice variants. Prior to qPCR, total RNA was isolated from siRNA-expressing HeLa cells, then reverse transcribed using the ImProm-II™ Reverse Transcription System. qPCR was The pGEM^®-T Easy Vector was used in the creation of plasmids encoding siRNA-resistant eIF4GI isoforms, which were transfected into siRNA-expressing HeLa cells to restore eIF4GI function. (3778)

Notes: In this study, the psiCHECK™ Vector was used in an investigation of the interaction between a microRNA and its potential target mRNA. Increased Fos expression in the paraventricular (PVN) and supraoptic (SON) nuclei is associated with hyperosmolality. In an effort to identify microRNAs that may regulate Fos expression, miRNA was isolated from the PVN and SON of mice after 10 days of 2% saline ingestion, and differentially expressed miRNAs were identified by microarray analysis. The miR-7b miRNA, which was overexpressed after saline treatment, was selected for further analysis as the fos gene 3´ UTR contains putative miR-7b binding sites. To investigate the potential interaction between miR-7b and Fos, the 3´ UTR of fos was subcloned downstream of the Renilla luciferase gene in the psiCHECK™ Vector. 293T cells were then co-transfected with the psiCHECK-Fos vector construct (0.8µg) and a vector expressing miR-7b and GFP (2.4µg). Luciferase assays were performed 42 hours post-transfection using the Dual-Luciferase^® Reporter Assay System. A 40% reduction in Renilla expression was observed in cells co-transfected with the miR-7b vector compared with cells transfected with psiCHECK-Fos and a control miRNA. (3560)

Notes: To monitor the effects of targeted degradation of micro RNA (miRNA) on Drosophila embryos, the authors cloned the full-length 3'UTRs of the proapoptotic factors hid and reaper into the psiCHECK™-2 Vector. The constructs were injected as plasmids (1µg/ml) mixed with 400µM sense and antisense miR-2 2'O-methyl oligoribonucleotides in early embryos. The total volume injected was equal to 5% of egg volume. After 10 hours development, the embryos were washed and lysed under agitation using 60µl lysis buffer and shaken at 750 rpm at room temperature for 30 minutes. The resulting lysate was cleared by centrifugation and three aliquots were tested using the Dual-Luciferase^® Reporter Assay System. The Renilla-to-firefly luciferase ratios from three to five independent replicates were averaged and normalized to the value of the miR-6 sense control, the most severe apoptotic phenotype when targeted for depletion. Statistical significance was assessed using the t test. (3292)

Notes: Having observed that blunt 27mers had increased potency in RNAi compared to 21mers or 27mers with 3' or 5' overhangs, these authors investigated what differences may account for these changes in gene silencing activity using the same target sequence in enhanced green fluorescent protein (EGFP). For one experiment, a PCR-generated fragment of the EGFP coding region spanning sites EGFPS1 and EGFPS2 was cloned into psiCHECK™-2 Vector in both sense and antisense orientations. Also, a PCR-generated fragment of the human heterogeneous nuclear ribonucleoprotein H (hnRNPH) coding region spanning sites H1 and H3 was similarly cloned in sense and antisense orientations. HEK293 cells were transfected with 150ng EGFP sense and antisense vectors plus EGFPS2 or control duplex RNAs. HCT116 cells were transfected with 100ng sense and antisense hnRNPH vectors with H3 or control duplex RNAs. The Dual-Luciferase^® assay was used to evaluate luciferase expression 24 hours post-transfection. In a separate EGFP RNAi experiment, the Steady-Glo^® Luciferase Assay System was used to monitor firefly luciferase activity to normalize transfection of HEK 293 cells. A further RNAi experiment targeted the firefly luciferase gene in the pGL3-Control Vector cotransfected with 20, 2 or 0.4 nM siRNA duplexes into HeLa cells. After 48 hours, the cells were lysed and 10µl tested using the Luciferase Assay System. To test the level of expression of human La antigen targeted for gene silencing, total RNA was harvested from HeLa cells using the SV 96 Total RNA Isolation System, reverse transcribed and used in real-time PCR. (3289)

Notes: The authors studied the effects of Embryonic Stem Cell (ESC)-specific regulation on the Pou5f1 promoter in human and mouse cells. To examine the effect of knockdown of Oct4 and Sox2 (two genes involved in ESC regulation) on the Pou5f1 promoter, a 3kb fragment of the human POU5F1 promoter was cloned into pGL3-Basic Vector and 100ng cotransfected with 100ng shRNA plasmids into mouse E14 ESCs. Five nanograms of pRL-SV40 Vector served as a transfection control. For the enhancer assay, a 461bp fragment of genomic DNA containing the SRR2 enhancer of Sox2 was amplified and cloned into the pGL3-Promoter Vector. The same amounts of plasmid, shRNA and transfection control were transfected into E14 ESCs as in the Pou5f1 promoter assay. To investigate gene knockdown in 293T cells, 5ng of the two open reading frame (ORF) constructs (the Luc-Sox2 and the Luc-Pou5f1 ORFs cloned into the psiCHECK™-2 Vector) were cotransfected with 100ng shRNA plasmid. The outcome was examined 48–60 hours post-transfection using the Dual-Luciferase^® Reporter Assay System. (3291)

Notes: In this study, the psiCHECK-2 vector was used to assist in selection of siRNA sequences that work optimally against their selected target. Dicer and DGCR8 coding sequences were individually cloned into the psiCHECK-2 multiple cloning site. The resulting vector and a synthetic siRNA duplex targeting the gene coding sequence were transfected into 293 cells and  Renilla luciferase activity was measured using the Dual Luciferase^® Assay System. Firefly luciferase activity was used to normalize the data.  siRNAs that caused greater than 80% reduction in Renilla luciferase signal were selected for further use. (3220)