Extended Data Fig. 5: Positioning of the ISS.
From: Visualizing maturation factor extraction from the nascent ribosome by the AAA-ATPase Drg1
(a) The ISS loop of Drg1 protomer B is fully inserted into the nucleotide binding pocket of the adjacent protomer A. (b) The ISS loop of protomer A is retracted from the nucleotide binding pocket of the adjacent protomer F. (c) and (d) Interaction with the inserted ISS loop stabilizes the D1D2 linker (c), while it is flexible and not well-defined in the cryo-EM map when the ISS loop is retracted (d). (e) and (f) Comparison of substrate translocation between Drg1 and Cdc48 (PDB: 6ONC) with a superposition of the two hexamers (e) and highlighted N-domain positioning relative to the inserted substrate as well as engagement of the substrate polypeptide chain inside the central channel via the pore loops (f).
