Cellular adhesion molecule that may play an important role in cell-cell interactions at interendothelial junctions (PubMed:9651350). Acts as a regulator of cell migration, probably via increasing cell-cell adhesion (By similarity). Promotes homotypic calcium-dependent aggregation and adhesion and clusters at intercellular junctions (PubMed:9651350). Unable to bind to catenins, weakly associates with the cytoskeleton (PubMed:9651350). The secreted form is produced following cleavage by ADAM10. Expressed in endothelial cells: localizes in vasculogenic rather than angiogenic endothelium (PubMed:9651350, PubMed:15541725). Strongly expressed in a subset of invasive cells of the placenta, named glycogen-rich trophoblasts cells (at protein level) (PubMed:15541725). glycogen-rich trophoblasts cells originate from the from the ectoplacental cone where they rapidly form tight islets (at protein level) (PubMed:16269175). In adult mice, present at high level in mesangial cells of kidney glomeruli, while expression was not detected in other types of perivascular cells (PubMed:15541725). N-glycosylated. 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. Mice are viable and fertile (PubMed:15541725, PubMed:18477666). Mice however show alterations in placental development that result in embryonic growth retardation: placentas are smaller and show limited angiogenesis and mis-segregation of the labyrinthine and intermediate layers (PubMed:18477666). Mice also display modifications in the structure and function of arteries, such as rearrangement of the arterial wall elastic fibers (PubMed:22205043).