Fig. 4: The relative rigid structures of the Dcr-2–Loqs-PD complex and further dsRNA bending in the translocation states.

a, Distortion of dsRNA in the early-translocation state. The dsRNA is presented in surface mode. Dcr-2–Loqs-PD is presented in cartoon mode. The translocation length of dsRNA (~8 bp) compared with the initial binding state is labelled. Domains interacting with dsRNA are opaque with a black outline. The axis of ideal A-form dsRNA extended from outside the helicase domain is shown by the black line. The helical axis of the helicase domain-bound dsRNA is shown by the red arrow. b, Overview of the mid-translocation state. The translocation length of dsRNA (~17 bp) is labelled in b as in a. The transparent cryo-EM map is shown in c. c, Distortion of dsRNA in the mid-translocation state is shown in the same mode as in a. The 3′-end binding region of PAZ in the mid-translocation state is labelled by the transparent orange circle. The axis of ideal A-form dsRNA extended from outside the helicase domain is shown by the black line. The helical axis of C-terminal dsRBD domain-bound dsRNA is shown by the red arrow. d, Overview of the interdomain contacts between DUF283 and the core region in the initial binding state. e, Magnified view of the interdomain contacts between the DUF283 and RIIIDb–RIIIDbi domains, corresponding to the orange-red box in d. f, Magnified view of the interdomain contacts between DUF283 with RIIIDa through the DP-linker, corresponding to the dark-blue box in d. g, Overview of the pre-dicing model. Model of the pre-dicing state based on the mid-translocation state with further RNA translocation. The translocation length of dsRNA (~29 bp) is labelled as in a.