Mutations in the tail of EBP50 perturb binding to ezrin. (A) Schematic of MBP-EBP50 tail (320–358) constructs, with the α-helical region that interacts with the ERM FERM domain indicated. Mutations or truncations were made in the tail of EBP50 that alter or remove key residues necessary for interaction with ezrin based on known structures. The additional alanine shown in red was added in the EBP50-LA construct to inhibit the tail–PDZ2 interaction. (B) Ezrin FERM coupled to CNBr-agarose was used to recover soluble MBP-EBP50 tails with indicated mutations/truncations. Gels were stained for total protein with IRDye.