Fig. 4.

Structural models of the Q2/Q3–CaM complex. (A) Side and cytoplasmic views of the complex, showing the channel subunits colored grey and the four CaM molecules in different pastels. In the side view, only three subunits are shown for clarity. Residues T35C (red), T45C (green), and T111C (blue) are shown in space fill. Red spheres, potassium ions; purple sphere, TEA-binding site; dark blue sphere, dummy ion to simulate trajectory of the tethered blocker. (B) Membrane and cytoplasmic view of the complex with CaM subunits inverted. Colors are the same as in A.