Fig. 3.

Scatchard plots of EGF-binding data obtained from various dimerization-impaired EGFR mutants in an EGFR-P background. 3T3 2.2 cells stably expressing EGFR-P (A) or EGFR-P bearing the mutations Del:242–259 (B), Y251A/R285S (C), or D279A/H280A (D) were grown in 24-well plates as described. Triplicate wells were treated with increasing concentrations of ¹²⁵I-labeled EGF, including 100-fold excess unlabeled EGF in the third well of each concentration at room temperature. The average of three independent experiments is indicated with the SE. (Insets) Saturation binding curves.