Figure 10.

Alpha-helical structure of Cx32’s CL1 and CT1 domains. CL1 is the only cytoplasmic domain rich in negative charges—it also contains positive charges, but they are on opposite sides of the helix. Our hypothesis is that, in coupled conditions, CL1 interacts with CT1. In CL1, acidic residues (E102, E109 and D113) and hydrophobic residues (M105 and L106) are on the same side of the helix. The idea is that, with uncouplers, a CaM lobe accesses the gating site by breaking the CL1–CT1 interaction (Ca–CaM–Cork model).