Fig. 2.

Yvh1 forces the release of Mrt4. a Atomic structure of the zinc-binding domain of Yvh1 modeled into the unassigned density. The small piece of extra density (blue) was assigned to the C terminus of Tif6 (see Supplementary Fig. 7b). b–d Interactions of Yvh1 with helices H43 and H44 (b), helix H89 (c), and sarcin-ricin loop (SRL) (d). Dashed lines, predicted hydrogen bonds. e Comparison of the P stalk RNAs in the Mrt4-bound (orange) and Yvh1-bound (blue) states. f Mrt4 in cartoon and transparent surface representation. A1221 of H42 bound in a pocket of Mrt4. g Mrt4 bound to P stalk RNA rotated ~120° clockwise relative to the view in (a) showing A1221 of H42 in the binding pocket of Mrt4. Residues of Mrt4 interacting with H42 are indicated. h Mrt4 from the early cytoplasmic-immediate (ECI) particle was docked onto H43 and H44 of the Yvh1-bound pre-Lsg1 (PL) particle, showing the movement of Mrt4 away from A1221 of H42