Part:BBa_K1442113

siRNA

siRNA are small interfering RNAs are strings of double stranded RNA (dsRNA) 20-24 base pairs long generated from longer strings of dsRNA. This dsRNA attracts the mammalian protein DICER, as dsRNA is not normal in mammalian cells. DICER will then process the dsRNA into smaller 22 base pair siRNAs. The siRNA duplex will then the RISC complex which will unwind the RNA so that it is single stranded. This can then bind to the target sequence to form more dsRNA which will be destroyed by the cell and inhibit transcription. DICER and RISC are part of the innate immune system to defend cells against viral infection – dsRNA is a feature that many viruses exhibit.

This graphic depicts the action of DICER and RISC. Smith-Waterman vs Blast in siRNA Oligonucleotide Design and SelectionDr. Cecilie BoysenSouthern California Bioinformatics Institute

The siRNA we have use is used to target the 3’UTR of the protein DPP-IV (CD26), the sequence for this siRNA has been used previously by inamoto et al, 2007 to knock down DPP-IV. However the flanking sequences have been designed so that the siRNA is only targeted by DICER in the negative sense.

Usage

The siRNA was intended to be used to knockdown DPP-IV.

This is a schematic of the entire replicon indicating the location of the siRNA in the replicon

Diagram generated by genious shows the location of the siRNA in the first synthesis module.

A section of DPP-IV 3’UTR BBa_K1442111 in the testing module forwards GFP for human cells BBa_K11442106 was intended to be used to test the siRNA.