Fig. 4.

Structural heterogeneity and sequence diversity of EC2 β4–β5 loop contribute to isoform specificity. (A) The EC2 β4–β5 samples conformational space in the PcdhγB3 simulation, forming several interactions with EC3 (numbering based on SI Appendix, Fig. S5). (B) Residue–residue interactions (shown as a heatmap of the fraction of the simulation pairs within 5 Å) of the EC2 β4–β5 loop (positions 154 to 161) with EC3 (positions 215, 216, 286, 288, 300, 302, and 304) differ between isoforms. (C) The differences in interacting residue pairs reflect diverse biochemical interactions of this loop with EC3.