Fig. 1.

Binding specificity analysis of selected DARPins by ELISA. (A) DARPins derived from RD selection with ERK2 (names starting with E) and phosphorylated ERK2 (pERK2) (names starting with pE) as targets were tested for interaction with ERK2 and pERK2. In addition, binding to the MAPK JNK1α1, JNK2α1, and p38α in the unphosphorylated and the phosphorylated state as well as to wells containing only neutravidin and BSA (NA+BSA) was assessed. As a further control, the unselected DARPin library member E3_5 was included. (B) Binding of selected DARPins to ERK2 and pERK2 was compared with the closely related MAPK ERK1 in the unphosphorylated and the phosphorylated state. The unselected DARPin E3_5 and the interaction with NA+BSA served as negative controls.