Gene knockdown, siRNA

The siRNAs assemble into a complex called RNA-induced silencing complex (RISC) and unwind in the process. The single stranded siRNAs then attach to complementary RNA molecules, thus targeting these RNAs for destruction—a process that is called gene knockdown. 

Fig. 14 Total (Kt, open circles) and non-specific (Xns, open squares) gene knockdown vs cationic lipid/siRNA molar charge ratio (pchg) at nl = 0.4 for MVL5/DOPC-siRNA (left), DOTAP/ DOPC-siRNA (middle), and DOTAP/DOPE-siRNA (right) complexes targeting EF luciferase mRNA in transfected L-cells. Reprinted with permission from [79]. Copyright 2007 American Chemical Society...

Fig. 12 Evaluation of gene knockdown effect by siRNA complexed with PEG-PAsp(DPT). a GL3 luciferase gene knockdown by siRNA complex with various block copolymers having varying charge ratios, commercially available reagent (RNAiFect), and naked siRNA evaluated in HuH-7 cells ( = 4 SD). GL3 and RL luciferases were pre-transfected by pGL3 and pRL plasmid DNA complexed with LipofectAMlNE. The siRNA complexes (GL3 knockdown) were then applied and evaluated by dual luciferase assay, b Endogenous gene (Lamin A/C) knockdown in the presence or absence of 50% serum evaluated in 293T cells...

Yoshikawa T, Uchimura E, Kishi M, Funeriu DP, Miyake M, Miyake J (2004) Transfection microarray of human mesenchymal stem cells and on-chip siRNA gene knockdown. J Control Release 96 227-232 Zhang Y, Feng XH, Derynck R (1998) Smad3 and Smad4 cooporale with c-Jun/c-Fos to mediate TGF-beta-induced transcription. Nature 394 909—913... 

A non-viral vector PEG-PEI was investigated in the delivery of siRNA to neural stem cells (NSCs). The SEM micrographs showed that PEG-PEI could condense siRNA to form spherical nanoparticles. The gene knockdown effect of PEG-PEI/siRNA nanoparticles was verified at the levels of mRNA and protein, which suggested that PEG-PEI may potentially be used as a siRNA delivery vector for neural regeneration therapy. ... 

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