Silencing efficiency

To calculate the gene silencing efficiency of the peptide/siRNA complexes, the expression of the protein of interest (in this case GAPDH) has to be first normalized with the expression of P-actin (protein for internal control) of the same sample. 

Equation 1. Formula to calculate gene silencing efficiency of the delivery system. The percentage represents the remaining GAPDH protein expression after transfection ... 

When investigating CL-siRNA complexes with the objective of optimizing their silencing efficiency (SE), it is of particular interest to reveal similarities and important differences with the process of optimizing transfection efficiency of CL-DNA complexes, which involves delivery of long dsDNA. Two key differences from the outset are the fact that siRNA complexes transport a much shorter cargo, and that they only need to deliver it to the cytoplasm, where the RNAi machinery is located. The shorter length of the siRNA duplex is expected to result in a weaker electrostatic stabilization of the complexes with CLs, and may, for some membrane compositions, lead to different structures. 

In addition, for CL-siRNA complexes, further exploration of the relationships between cationic lipid valence, complex stability, silencing efficiency, and cytotoxicity with a series of multivalent lipids such as the MVLS or DLs is a logical next step. 

Kim SH, Mok H, Jeong JH et al (2006) Comparative evaluation of target-specific GFP gene silencing efficiencies for antisense ODN, synthetic siRNA, and siRNA plasmid complexed with PEI-PEG-FOL conjugate. Bioconjug Chem 17 241-244... 

Gredell J, Berger A, Walton S (2008) Impact of target mRNA structure on siRNA silencing efficiency a large-scale study. Biotechnol Bioeng 100 744—755... 

The high gene silencing efficiency of the PEG-PAsp(DPT) complex may be attributed to the presence of the secondary amino group with a lower pfCa in the complex that promotes siRNA transport into the cytoplasm by buffering the endosomal cavity, in addition to the increased tolerance against nuclease attack due to complexation. These results, obtained for the engineered block catiomer of PEG-PAsp(DPT), facilitates the clinical use of siRNA for the treatment of various diseases. 

Several groups explored the effect of target mRNA secondary and/or tertiary structure on the silencing efficiency of specific... 

Y. Kwon, Before and after endosomal escapes roles of stimuU-converting siRNA/polymer interactions in determining gene silencing efficiency, Acc. Chem. Res. 45 (2012) 1077-1088. 

In order to overcome the limitations associated with siRNA delivery in vivo, a group of dendritic nanocarriers derived either fromPG or PEI were synthesized and their silencing efficiency was evaluated. Among the nanocarriers evaluated in this study, the best siRNA transfection efficiency with regard to toxicity was observed for PG amine. In general, successful systemic delivery... 

Kume, H., Hino, K., Galipon, J., Ui-Tei, K. (2014). A-to-I editing in the miRNA seed region regulates target mRNA selection and silencing efficiency. Nucleic Acids Res, 42 (15), 10050-10060. 

Jere, D., Kim, J. E., Arote, R. et al. 2009. Akt 1 silencing efficiencies in lung cancer cells by sh/si/ssiRNA transfection using a reductable polyspermine carrier. Biomaterials 30 1635-1647. 

S. Jung, S.H. Lee, H. Mok, H.J. Chimg, T.G. Park, Gene silencing efficiency of siRNA-PEG conjugates effect of PEGylation site and PEG molecular weight. J. Control. Release, 144 (3) 306-313, 2010. 

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