[3] The name of this protein family is derived from a mutant phenotype resulting from mutation of AGO1 in Arabidopsis thaliana, which was likened by Bohmert et al. to the appearance of the pelagic octopus Argonauta argo.

Argonaute proteins are the active part of RNA-induced silencing complex, cleaving the target mRNA strand complementary to their bound siRNA.

Also the degree of complementarity between the two strands of the intermediate RNA duplex defines how the miRNA are sorted into different types of Argonaute proteins.

Also, the Argonaute-miRNA complex can adjust protein production by recruiting cellular factors such as peptides or post translational modifying enzymes, which degrade the growing of polypeptides.

[8] In plants, once de novo double-stranded (ds) RNA duplexes are generated with the target mRNA, an unknown RNase-III-like enzyme produces new siRNAs, which are then loaded onto the Argonaute proteins containing PIWI domains, lacking the catalytic amino acid residues, which might induce another level of specific gene silencing.

The PAZ domain is an RNA binding module that recognizes single-stranded 3′ ends of siRNA, miRNA and piRNA, in a sequence independent manner.

[9] At the interface of PIWI and Mid domains sits the 5′ phosphate of a siRNA, miRNA or piRNA, which is found essential in the functionality.

It was later found that the MC motif is not involved in mRNA cap binding [8] In humans, there are eight AGO family members, some of which are investigated intensively.

It has been reported several tiny non-coding RNAs(microRNAs) are related with human cancers, like miR-15a and miR-16a are frequently deleted and/or down-regulated in patients.

This process has been seen in a wide range of organisms, such as Neurospora fungus (in which it is known as quelling), plants (post-transcriptional gene silencing) and mammalian cells(RNAi).

In 2016, a group from Hebei University of Science and Technology reported genome editing using a prokaryotic Argonaute protein from Natronobacterium gregoryi.

However, evidence for application of Argonaute proteins as DNA-guided nucleases for genome editing have been questioned, with the retraction of the claim from the leading journal.