Description
The Argonaute (AGO) family proteins are defined by the presence of Piwi-Argonaute-Zwille (PAZ)) and PIWI domains 2, and mediate silencing via cleavage of mRNAs 3 or inhibition of translation 4.
The AGO family proteins fall into two subfamilies, one named after Arabidopsis Argonaute and the other after Drosophila PIWI 5.
In most organisms investigated so far, PIWI proteins bind Piwi-interacting RNAs (piRNAs) and are functionally involved in the regulation of germ cells 6, 7.
By contrast, AGO proteins have distinct roles in the small-RNA-mediated gene silencing pathway.
Argonaute-2 (Ago2) is a key component of the RNA-induced silencing complex (RISC) that mediates downregulation of mRNA by microRNAs.
Its presence in extracellular vesicles (EVs) has been postulated to be important for the activity of EV-carried miRNA in modulating gene expression in recipient cells