Argonaute RISC catalytic component 3 (AGO3)

Argonaute RISC catalytic component 3 (AGO3) is a member of the Argonaute protein family, central to the RNA-induced silencing complex (RISC), and plays a key role in RNA interference (RNAi) and post-transcriptional gene silencing[1][2][3][7]. AGO3 is an RNA-binding endonuclease characterized by PAZ and PIWI domains; it binds microRNAs (miRNAs), small interfering RNAs (siRNAs), and is uniquely responsive to certain tiny RNAs (tyRNAs), enabling catalytic “slicing” of target mRNAs under specific sequence and structural conditions[2][3]. While AGO2 is the primary slicer in mammals, AGO3 shares the catalytic tetrad and can be activated by particular guide RNAs, but its activity and requirements are distinct and more restricted, relying on the presence of RNA flanking regions and specific guide sequences[2][3]. AGO3’s biological functions include stabilization and regulation of gene silencing by miRNA and siRNA pathways, affecting cellular differentiation, proliferation, and development. AGO3 has been implicated in disease, notably in certain cancers and developmental disorders, but is not currently the direct pharmacological target of any approved drugs[1]. Its manipulation presents potential therapeutic opportunity but raises concerns about specificity and off-target gene regulatory effects[2][3][6].

Other names

Protein argonaute-3EIF2C3Argonaute3hAgo3eIF-2C 3eIF2C 3hAGO3FLJ12765Eukaryotic translation initiation factor 2C 3Argonaute 3RISC catalytic componenteukaryotic translation initiation factor 2C, 3

Not targeted by drugs directly; endogenous small RNAs (miRNA, siRNA, tiny RNAs/cityRNAs) guide AGO3 for gene silencing