Small interfering RNA
Small interfering RNA (siRNA)[a] is a class of double-stranded RNA molecules, 20-25 base pairs long.
siRNA plays many roles, but it is most notable in the RNA interference (RNAi) pathway,[1] where it interferes with the expression of certain genes. Genes are only affected if they have nucleotide sequences complementary to those of the siRNA.
siRNA functions by breaking down mRNA after transcription.[2] This prevents translation of the gene into protein. siRNA also acts in RNAi-related pathways, e.g., as an antiviral mechanism or in shaping the chromatin structure of a genome. The complexity of these pathways is only now being worked out.
Small Interfering RNA Media
- SiRNA Structure2.svg
SVG schematic of siRNA structure
- SiRNA mechanism.2.png
siRNA mechanism
- 2ffl-by-domain.png
Dicer protein colored by protein domain.
- The Ping-Pong Method.png
A simplified version of the Ping-Pong Method, involving proteins Aubergine (Aub) and Argonaute-3 (Ago3) cleaving the 3' and 5' ends of piRNA.
- SiRNA mechanism.svg
The generalised RNAi mechanism upto the molecular level depicting the role of various cellular proteins and external siRNAs.
Notes
- ↑ sometimes known as short interfering RNA or silencing RNA
References
- ↑ Hannon G.J. & Rossi J.J. 2004. Unlocking the potential of the human genome with RNA interference. Nature 431 (7006): 371–378. [1]
- ↑ RNA Interference: biology, mechanism, and applications