Define the Best Conditions for siRNA Delivery in Cultured Cells

The Silencer siRNA Starter Kit is the recommended kit for those just starting siRNA experiments, as it features a convenient package of control siRNAs, siRNA transfection agent, and downstream detection reagents. The included siPORT™ NeoFX™ Transfection Agent effectively delivers siRNAs to a broad range of cell lines, and supports both reverse and forward (“pre-plating”) transfection protocols. The kit also includes a well-characterized Silencer GAPDH siRNA, which has been shown to strongly down regulate the GAPDH gene in human, mouse, and rat cells (see sidebar, Why Use GAPDH Control siRNAs?), as well as a non-targeting negative control siRNA known as Silencer Negative Control #1 siRNA. Finally, the kit includes three different systems for monitoring GAPDH siRNA induced knockdown. An Anti-GAPDH antibody is provided to assess GAPDH protein levels by Western blot or immunofluorescence. The Ambion KDalert™ GAPDH Assay is also provided to quickly measure GAPDH enzymatic activity. This assay has the added benefit that it can be used to assess cell viability. Finally, RT-PCR primers, for real-time quantitative RT-PCR detection of GAPDH mRNA are included.

The Silencer siRNA Transfection II Kit is the ideal choice for optimizing siRNA transfection conditions in any size plate. This kit includes both siPORT Amine and siPORT NeoFX Transfection Agents for broad cell line compatibility. Both transfection agents support traditional “pre-plating” transfection protocols as well as reverse transfection procedures, where cells are transfected during subculturing. Transfection efficiency is monitored using Silencer GAPDH siRNA and the non targeting Silencer Negative Control #1 siRNA. Because two transfection agents are included, the Ambion Silencer siRNA Transfection II Kit makes it easy to identify the appropriate siRNA delivery agent and conditions for your cell type.

The Silencer CellReady™ siRNA Transfection Optimization Kit was developed specifically to accelerate siRNA transfection optimization in 96-well plates. This kit comes with three 96-well plates containing pre-plated positive control siRNA targeting human, mouse, and rat GAPDH and nontargeting Negative Control siRNA. It also includes siPORT NeoFX Transfection Agent. The convenient arrangement of siRNAs on each plate can be used to assess the effectiveness of up to 24 transfection conditions in duplicate.

Detailed instructions included with all three siRNA transfection kits help new users test important variables, such as choice of transfection agent, transfection agent volume, cell number, timing of a potential post-transfection wash, and timing of the post-transfection assay.

The efficiency of siRNA delivery is most frequently monitored by measuring the reduction in GAPDH mRNA and/or protein levels in cells transfected with GAPDH siRNA relative to cells transfected with negative control siRNA.

The KDalert™ GAPDH Assay Kit simplifies this step by providing researchers with a reliable measure of GAPDH enzyme activity in cultured human, mouse, or rat cells. With this straightforward assay, which can be completed in under 30 minutes, researchers use a microplate fluorometer for quantitation (an absorbance reader can also be used). In addition to its use for rapid monitoring of GAPDH siRNA induced knockdown, the assay can also be used in the same experiment to monitor transfection agent induced toxicity (Figure 2). For this analysis, GAPDH activity from negative control siRNA transfected cells is compared to that of untreated cells. The KDalert GAPDH Assay Kit integrates seamlessly with all of the Ambion transfection optimization products listed in this article.