Dicer in the context of "Argonaute"

Play Trivia Questions online!

or

Skip to study material about Dicer in the context of "Argonaute"




⭐ Core Definition: Dicer

Dicer, also known as endoribonuclease Dicer or helicase with RNase motif, is an enzyme that in humans is encoded by the DICER1 gene. Being part of the RNase III family, Dicer cleaves double-stranded RNA (dsRNA) and pre-microRNA (pre-miRNA) into short double-stranded RNA fragments called small interfering RNA and microRNA, respectively. These fragments are approximately 20–25 base pairs long with a two-base overhang on the 3′-end. Dicer facilitates the activation of the RNA-induced silencing complex (RISC), which is essential for RNA interference. RISC has a catalytic component Argonaute, which is an endonuclease capable of degrading messenger RNA (mRNA).

↓ Menu

In this Dossier

Dicer in the context of PiRNA

Piwi-interacting RNA (piRNA) is the largest class of small non-coding RNA molecules expressed in animal cells. piRNAs form RNA-protein complexes through interactions with piwi-subfamily Argonaute proteins. These piRNA complexes are mostly involved in the epigenetic and post-transcriptional silencing of transposable elements and other spurious or repeat-derived transcripts, but can also be involved in the regulation of other genetic elements in germ line cells.

piRNAs are mostly created from loci that function as transposon traps which provide a kind of RNA-mediated adaptive immunity against transposon expansions and invasions. They are distinct from microRNA (miRNA) in size (26–31 nucleotides as opposed to 21–24 nt), lack of sequence conservation, increased complexity, and independence of Dicer for biogenesis, at least in animals. (Plant Dcl2 may play a role in rasi/piRNA biogenesis.)

↑ Return to Menu

Dicer in the context of DCL1

DCL1 (an abbreviation of Dicer-like 1) is a gene in plants that codes for the DCL1 protein, a ribonuclease III enzyme involved in processing double-stranded RNA (dsRNA) and microRNA (miRNA). Although DCL1, also called Endoribonuclease Dicer homolog 1, is named for its homology with the metazoan protein Dicer, its role in miRNA biogenesis is somewhat different, due to substantial differences in miRNA maturation processes between plants and animals, as well due to additional downstream plant-specific pathways, where DCL1 paralogs like DCL4 participate, such Trans-acting siRNA biogenesis.

↑ Return to Menu