Single-stranded RNA molecule (usually from 21 to 25 nucleotides in length) produced by the cleavage and processing of double-stranded RNA; binds to complementary sequences in mRNA and brings about the cleavage and degradation of the mRNA. Some siRNAs bind to complementary sequences in DNA and bring about their methylation.
© 2005 by W. H. Freeman and Company. All rights reserved. Pierce, B. Genetics: A conceptual approach. 2nd Edition.