Extended Data Fig. 7: Substrate binding and interaction.

Structures are superposed on the scaffold domain. The inward-facing pocket is divided into the binding chamber and a vestibule. The red broken line running from Asn117 to Asn223 defines the boundary between vestibule to binding chamber. (a) 4-CPA binding position and poses in the prebinding in the PIN8-inward conformation, binding and partly release in the PIN8-outward conformation. Square with question mark represents the missing state. (b) IAA binding position and poses in the prebinding in the PIN1-inward conformation, binding in the PIN3-inward conformation, and partly release in the PIN8-outward conformation. Square with question mark represents the missing state. (c) Overlay of NPA binding poses from PIN8, PIN1, PIN3. NPA binds in both the binding chamber and the vestibule and forms hydrogen bonds to both Asn117 and Asn223. The planes define the position of the ring systems of NPA, IAA and 4-CPA within the vestibule and binding chamber in the inward monomer and outward facing monomer. Figure created with PyMOL v5.0.4, Molecular Graphics System (Schrödinger, LLC).