Fig. 3.

Putative cadherin binding reaction and conformational energy diagram. (A) In step I, two cadherin monomers with their A-strands in the “closed” state (M) undergo a conformational change whereby the A-strands assume the “open” state (O). In step II, the “open” cadherin protomers associate with each other to form a strand-swapped dimer (D). (B) Conformational free energies associated with each step of the binding reaction shown in A. Note that O is either equivalent or more positive in free energy than the true intermediate (I^*).