Cellular adhesion molecule that may play an important role in cell-cell interactions at interendothelial junctions (By similarity). Acts as a regulator of cell migration, probably via increasing cell-cell adhesion (PubMed:21402705). Promotes homotypic calcium-dependent aggregation and adhesion and clusters at intercellular junctions (By similarity). Unable to bind to catenins, weakly associates with the cytoskeleton (By similarity). The secreted form is produced following cleavage by ADAM10. Expressed in highly vascularized tissues including the heart and placenta, but most tissues contain a low level of expression (PubMed:11063261). Prominent expression in the spleen (PubMed:11063261). Present in villous and extravillous trophoblast (at protein level) (PubMed:21402705). Cleaved by ADAM10 close to the transmembrane domain to release the Protocadherin-12, secreted form in the serum. Cleavage results in reduced cellular adhesion in a cell migration assay. The disease is caused by variants affecting the gene represented in this entry.