This domain is found in Endoribonuclease Dicer from chordates. This dsRNA endoribonuclease is involved in the cleavage of long RNA precursors into short dsRNAs and plays a role in gene silencing. Dicer shows two N-terminal helicase domains (Pfam:PF04851 and Pfam:PF00271), a dimerisation domain (Pfam:PF03368), a Platform domain, a PAZ domain (Pfam:PF02170), two RNase III a/b domains (Pfam:PF00636) and a dsRNA-binding domain in its C-terminal region. This entry represents the partner-binding domain, which folds into a four-helix bundle. It is is responsible for the interactions with the dsRNA-binding proteins that support the enzymatic activity of Dicer [1,2].

1: Cryo-EM Structure of Human Dicer and Its Complexes with a Pre-miRNA Substrate. Liu Z, Wang J, Cheng H, Ke X, Sun L, Zhang QC, Wang HW; Cell. 2018;173:1191-1203. PMID:29706542

2: Dicer-TRBP complex formation ensures accurate mammalian microRNA biogenesis. Wilson RC, Tambe A, Kidwell MA, Noland CL, Schneider CP, Doudna JA; Mol Cell. 2015;57:397-407. PMID:25557550