Phi analysis of the TBS and αM2M3. (A) Unliganded gating REFERs for αM2M3 amino acids. The slope (phi) is given in each plot. (B) Comparison of phi values with versus without agonists (dashed lines, mean). For TBS residues, phi is higher with versus without agonists, but for αM2M3 residues, it is the same.