Exceptional gene silencing specificity for reliable phenotypes

siRNA pools (siPOOLs) are high complexity pools of 30 optimally-designed siRNAs that were demonstrated to efficiently remove off-target effects and improve reliability of results (Hannus et al., 2014). Our Pack Hunter (pooling) approach counters off-targeting of individual siRNAs by diluting their concentrations below thresholds that stimulate phenotypes. With proprietary design algorithms, siRNA sequences within siPOOLs are also optimized for maximal transcript coverage, efficient hybridization and filtered against paralogues, enabling highly efficient and specific gene silencing.

Benefits of using siPOOLs

Key Problem: Off-target effects of siRNAs

Scientists have been using RNA interference (RNAi) as a rapid and efficient tool to establish gene function. Yet the off-target effects and variable performance of short interfering RNAs (siRNAs) remain a troubling drawback, consuming precious time and resources in validation efforts.

siRNAs typically bind with full complementarity to target RNA transcripts, guiding their degradation by the RNAi machinery. Off-target effects are largely caused by siRNAs mimicking endogenous gene regulators, micro RNAs (miRNAs). As miRNAs require only a 6 base seed match to 3' untranslated regions (UTR) to trigger transcript downregulation, siRNAs can alter the expression of numerous unintended targets when processed via this mechanism.

How siPOOLs Improve Specificity

Individual siRNAs or low complexity siRNA pools containing 3-4 siRNAs often hit multiple off-target genes and exhibit variable target gene knock-down.
Short interfering RNA (siRNA) pools, siPOOLs are highly complex and defined pools of 30 siRNAs, each siRNA present at picomolar working concentrations. This:

• Dilutes the off-target signature of each siRNA, increasing on-target specificity.
• Ensures co-operative knock-down of the target gene, producing more robust and reliable results.

Optimized and detailed siRNA design

With defined siRNA sequences within the siPOOL, targeting can be optimized against specific transcript isoforms or closely related genes. Proprietary siRNA design algorithms select the most potent siRNAs based on thermodynamic properties that favour guide strand loading into the RNA-induced silencing complex (RISC) (refer Technote 2 for more details on siPOOL design). Using latest RefSeq annotations and genome-wide paralogue filtering, siPOOLs are designed for maximum coverage of all targeted transcripts with high specificity.