Fig. 4.

Structure-guided identification of CIF peptides. (A) Multiple sequence alignment of the CIF1–4 peptides. The conserved sTyr is highlighted in red, hydroxyprolines are in yellow, and the C-terminal asparagine/histidine is shown in blue. (B) GCI assays of CIF3^WT or CIF3^nsY46 versus the wild-type GSO1/SGN3 ectodomain. Flow rate was 100 µL min⁻¹. Sensorgrams are presented with raw data in red and their respective fits in black. Binding kinetic analyses were performed with a 1-to-1 binding model. Table summaries of kinetic parameters are shown alongside. (C) ITC assays of CIF2 or CIF4 wild-type peptides versus the SGN3 wild-type ectodomain. Table summaries for dissociation constants (K_d) and binding stoichiometries (N) are shown (±fitting error).