Extended Data Fig. 5: Ligand structures and the orthosteric binding pocket.

a, Superposition of ligand structures in each of the Ste2 structures determined. Amino acid residues in α-factor are all labelled (black), whereas only residues in the antagonist that differ from α-factor are labelled (blue boxes). b, Superposition of Ste2•LF (grey) and Ste2•Ant (purple) to highlight changes in the position of residues (sticks) within the orthosteric binding site. c, Amino acid residues that interact with the ligand (grey boxes) in Ste2 structures. d, Number of receptor-ligand contacts determined for each structural element in Ste2 and how they change during receptor activation. e, Changes in the orthosteric binding site volume (surface representation) during Ste2 (cartoon representation) activation. Analyses were performed in the absence of the ligand and extracellular N-terminal domain coordinates (residues 1–37). Binding pocket volumes were calculated using the software HOLLOW⁶¹ and the results were visualized in Chimera. The PDB output (cavity filled dummy atoms) from HOLLOW were converted to a map and the volumes of the binding pocket were measured using Chimera’s “Measure Blob” function.