Summary information and primary citation

PDB-id
8vaj; SNAP-derived features in text and JSON formats; DNAproDB
Class
RNA binding protein-RNA
Method
X-ray (3.45 Å)
Summary
Human argonaute3 bound to cityrna and target RNA
Reference
Zhang H, Sim G, Kehling AC, Adhav VA, Savidge A, Pastore B, Tang W, Nakanishi K (2024): "Target cleavage and gene silencing by Argonautes with cityRNAs." Cell Rep, 43, 114806. doi: 10.1016/j.celrep.2024.114806.
Abstract
TinyRNAs (tyRNAs) are ≤17-nt guide RNAs associated with Argonaute proteins (AGOs), and certain 14-nt cleavage-inducing tyRNAs (cityRNAs) catalytically activate human Argonaute3 (AGO3). We present the crystal structure of AGO3 in complex with a cityRNA, 14-nt miR-20a, and its complementary target, revealing a different trajectory for the guide-target duplex from that of its ∼22-nt microRNA-associated AGO counterpart. cityRNA-loaded Argonaute2 (AGO2) and AGO3 enhance their endonuclease activity when the immediate 5' upstream region of the tyRNA target site (UTy) includes sequences with low affinity for AGO. We propose a model where cityRNA-loaded AGO2 and AGO3 efficiently cleave fully complementary tyRNA target sites unless they directly recognize the UTy. To investigate their gene silencing, we devised systems for loading endogenous AGOs with specific tyRNAs and demonstrated that, unlike microRNAs, cityRNA-mediated silencing heavily relies on target cleavage. Our study uncovered that AGO exploits cityRNAs for target recognition differently from microRNAs and alters gene silencing.

Cartoon-block schematics in six views (download the tarball)

PyMOL session file Download PDB file View in 3Dmol.js