Fig. 3.

Quantitative protein interaction maps for EGFR, FGFR1 and IGF1R. Two maps are shown for each receptor. The maps on the left (A, C, E) are constructed using physiological peptides derived from EGFR, FGFR1 and IGF1R, respectively; the maps on the right (B, D, F) are constructed using nonphysiological peptides derived from EGFR, FGFR1 and IGF1R, respectively. Red circles represent phosphopeptides, green circles represent SH2 domains and blue circles represent PTB domains. Lines connecting peptides to domains indicate observed interactions, colored according to the affinity of the interaction (see legend). The circles that lie outside the rectangle of individual domains and are connected by black lines to two other circles, represent tandem domains. They comprise the two domains to which they are connected. The circles that lie outside the rectangle but are connected to only one other circle represent proteins that contain both an SH2 domain and a PTB domain.