Predesigned siRNA

RNA interference (RNAi) is a powerful experimental tool in the laboratory, using homologous double-stranded RNA (dsRNA) to induce silencing of target genes, enabling rapid blockade of gene activity. BOC RNA offers siRNA design services and a comprehensive predesigned siRNA library to meet research needs in biology and drug discovery.

Introduction

Studies in recent years have shown that some short fragments of double-stranded RNA can efficiently and specifically block the expression of specific genes in vivo by inducing mRNA degradation of specific genes, causing cells to exhibit a specific gene deletion phenotype, which is called RNA interference (RNAi). siRNA (small interfering RNAs) is a short double-stranded RNA molecule that can target mRNAs with homologous and complementary sequences to degrade specific mRNAs. The discovery of RNAi has epoch-making significance. It not only deeply reveals the mechanism of gene silencing in cells, but also is a powerful tool for gene function analysis in the post-genome era, which greatly promotes the process of revealing the mysteries of life. Now more and more researchers are beginning to use RNAi to study the gene expression of organisms. RNAi technology can be widely used in functional genomics, drug target screening, cell signaling pathway analysis, disease treatment, etc.

RNAi Protocol

1. siRNA design
2. shRNA annealing
3. Enzyme digestion and recovery of vector fragments
4. Ligation of vector and shRNA fragment
5. Transformation
6. Clone picking and identification
7. Expansion of positive clones and extraction of plasmids

The focus of RNAi technology is siRNA design.

siRNA Design

1. Design Approach

(1) Find in the literature: look for validated ones (preferred)
(2) Predesigned siRNA libraries: contains validated siRNA fragments
(3) Software design

2. Predesigned siRNA Libraries

BOC RNA's predesigned siRNA libraries provide the most attractive collection of siRNAs for high-throughput screening by targeting genes of high therapeutic value. Flexible product formats help life scientists who study specific gene panels or need to target all available pharmacogenomics. Real-time PCR analysis of hundreds of pre-designed siRNAs resulted in >75% knockdown efficiency for 80% of the siRNAs and >90% induction of target silencing for over 40% of the siRNAs.

3. siRNA Design Service

(1) Screening of target sequences prior to designing RNAi experiments
(2) Principles of RNAi target sequence selection:

• Starting from the AUG start codon of the transcript (mRNA), look for the "AA" double-linked sequence and write down the 19-base sequence at its 3' end as a potential siRNA target site. Studies have shown that siRNAs with a GC content of about 45%-55% are more effective than those with a higher GC content.
• Potential sequences are compared with the corresponding genomic database (human, mouse, rat, etc.) and those homologous to other coding sequences/ESTs are excluded.
• Selecting the right target sequence for synthesis. Often a gene requires the design of multiple target sequences for siRNA to find the most efficient siRNA sequence.

4. Negative Control

A complete siRNA experiment should have a negative control. The siRNA used as a negative control should have the same composition as the selected siRNA sequence, but no apparent homology to the mRNA. It is common practice to disrupt the selected siRNA sequence and again check the results to ensure that it is not homologous to other genes in the target cell.

Features & Benefits

• High siRNA knockdown rate
• Maximize siRNA knockdown while minimizing off-target effects
• Competitive price
• Full range of service options