Extended Data Fig. 9: DICER end recognition, 3′-flanking contacts and conserved PAZ domain movement.
From: DICER cleavage fidelity is governed by 5′-end binding pockets
a, Model for 5′-end recognition by DICER. The 5′-nt engages two alternative binding pockets. Left, a 5′-G-favoured pocket where H992 provides a positive charge and D991 acts as an H-bond acceptor, forming a hydrogen-bonding web with purine edges. Right, a 5′-U-favoured pocket where R1003 contributes positive charge and R821 serves as an H-bond donor compatible with uridine. b, Y-cluster contacts with the 3′-overhang region differ between RNAs. Top, DICER bound to pre-let-7a-1GYM (orange). Overall view (left) and close-ups (middle, right) show defined interactions between the 3′-overhang region and the Y-cluster pocket. Bottom, DICER bound to pre-mir-517a_GU (green). Overall view (left) and close-ups (middle, right) highlight altered positioning of the 3′-overhang region near the Y-cluster. Question marks indicate weaker or ambiguous density/contacts relative to pre-let-7a-1GYM. c, Superposition of DICER homologues in dicing and apo states reveals PAZ-domain movement; apo conformations are shown in grey.
