Direct measurements of adhesive interactions between cadherin extracellular domains

Examines the intermolecular alignments that mediate the hemophilic adhesion between cadherin ectodomains from Xenopus. We used the surface force apparatus to measure directly the force between oriented, cadherin monolayers as a function of their separation distance. These measurements identified relative domain alignments that give rise to hemophilic, adhesive interactions between proteins. They show that cadherin extracellular domains bind in at least two antiparallel configurations. The two adhesive contacts are separated by a distance equal to one cadherin domain. These results suggest that cadherin adhesion is not determined by a single binding site, but may involve several domains