Background
This gene encodes a member of the membrane-associated guanylate kinase (MAGUK) family
of proteins, and acts as a tight junction adaptor protein that also regulates adherens
junctions. Tight junctions regulate the movement of ions and macromolecules between
endothelial and epithelial cells. The multidomain structure of this scaffold protein, including
a postsynaptic density 95/disc-large/zona occludens (PDZ) domain, a Src homology (SH3)
domain, a guanylate kinase (GuK) domain and unique (U) motifs all help to co-ordinate
binding of transmembrane proteins, cytosolic proteins, and F-actin, which are required for
tight junction function. Alternative splicing results in multiple transcript variants encoding
different isoforms
