Dicer

Genomics

See Also

• RNA Interference (RNAi)

Description

Dicer is an RNAse III nuclease which cuts dsRNA into siRNAs and pre-miRNA into miRNA. The structure of Dicer is an elongated molecule with a PAZ domain on one end and dual RNase III domains on the opposing end. Dicer works by recognizing the ends of dsRNA with its PAZ domain and then cutting the dsRNA with its RNase III domains. The distance between the PAZ and RNase III domains determines the length of the siRNA produced by Dicer, which varies by species but is typically in the range of 22 to 30 nucleotides.

Source

Discussion

RNA interference (RNAi) is an apparently ancient defence mechanism against foreign double-stranded RNA (dsRNA). RNAs of just 22 nucleotides in length, called small interfering RNAs (siRNAs), are snipped from longer dsRNA chains by an enzyme called Dicer. The antisense strand of the siRNA is used by an RNA-induced silencing complex (RISC) to guide messenger RNA (mRNA) cleavage, so promoting mRNA degradation.

Links

• Role of Dicer in dsRNA interference

Attribution

• This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Dicer".