Nectin/PRR: An immunoglobulin-like cell adhesion molecule recruited to cadherin-based adherens junctions through interaction with afadin, a PDZ domain-containing protein

We have isolated a novel actin filament-binding protein, named afadin, loca lized at cadherin-based cell-cell adherens junctions (AJs) in various tissu es and cell lines. Afadin has one PDZ domain, three proline-rich regions, a nd one actin filament-binding domain. We found here that afadin directly in teracted with a family of the immunoglobulin superfamily, which was isolate d originally as the poliovirus receptor-related protein (PRR) family consis ting of PRR1 and -2, and has been identified recently to be the alphaherpes virus receptor. PRR has a COOH-terminal consensus motif to which the PDZ d omain of afadin binds. PRR and afadin were colocalized at cadherin-based ce ll-cell AJs in various tissues and cell lines. In E-cadherin-expressing EL cells, PRR was recruited to cadherin-based cell-cell AJs through interactio n with afadin. PRR showed Ca2+-independent cell-cell adhesion activity. The se results indicate that PRR is a cell-cell adhesion molecule of the immuno globulin superfamily which is recruited to cadherin-based cell-cell AJs thr ough interaction with afadin. We rename PRR as nectin (taken from the Latin word "necto" meaning "to connect").