Figure 7.

Example currents for α-subunit loop C perturbations. (A) Modes with different substitutions at αP197. For each mutation, examples of the various modes are shown directly below the mutant designation. Only two modes are apparent with larger side chains (see Fig. 2 for Ala mutation). (B) Alanine scan of loop C. Modes are apparent with an alanine substitution at every loop C position except αY190 and αY198 (boxed). (C) Deletions. Modes are present with deletions of some loop C residues. (D) Modes are present with αT196P added to the αP197A background. All experiments: adult AChRs, 30 µM ACh; −100 mV; open is down.