Fig. 3: Generic residue numbering denotes corresponding residues across receptors.

Generic residue numbers (GRNs) are equivalent residues in structure and sequence across receptors, enabling comparisons of, e.g., mutations^39,53,85, sequence conservation³⁹ structural contacts, and ligand interactions^50,85. a A GRN is composed of the segment identifier and the numeric residue index. The structural alignment of the GAIN helix 6 segment of nine human adhesion G protein-coupled receptors indicates the GRN at the respective aligned residue Cα (spheres). b sequence alignment of the nine receptors with the receptor subfamily indicated in bold in front of the receptor name. Sequence alignment is based on structural alignment, with the H6.50 GRN denoting the most conserved residue in the segment (bold). All other segment residues are indexed relative to the .50 position. c residue table of aligned segments colored by chemical properties.