Nectins are immunoglobulin-like adhesion molecules that interact with afadin. Afadin is an actin filament-binding protein that connects nectins to the actin cytoskeleton. The nectin-afadin system organizes adherens junctions cooperatively with the cadherin-catenin system in epithelial cells.
The nectin/PRR-family consists of four members, nectin-1, -2, -3 and -4. All the members of the nectin family have two or three slice variants. Nectin 3 is mainly expressed in testis and placental tissues and interacts in vivo with both long and short isoforms of afadin.