Tight junctions represent one mode of cell-to-cell adhesion in epithelial or endothelial cell sheets, forming continuous seals around cells and serving as a physical barrier to prevent solutes and water from passing freely through the paracellular space.

The protein encoded by this immunoglobulin superfamily gene member is an important regulator of tight junction assembly in epithelia.

Multiple transcript variants encoding two different isoforms have been found for this gene.

[7] F11 receptor has been shown to interact with MLLT4,[8] CASK[8][9] and Tight junction protein 1.

[8][10] This article incorporates text from the United States National Library of Medicine, which is in the public domain.