Definition:
Small pieces of double-stranded (ds) RNA, usually about 21 nucleotides long, with 3' overhangs (2 nucleotides) at each end. Each strand has a 5' phosphate group and a 3' hydroxyl (OH) group.
siRNAs are produced from dsRNA or hairpin looped RNA, using RNase or restriction enzymes.
siRNAs are useful tools in molecular medicine because they can inhibit translation, and thus production, of specific proteins based on their nucleotide sequences. They act by neutralizing mRNA for the particular target protein.
Also Known As: small interfering RNA
