The MAGUK (membrane-associated guanylate kinase homologs) family of proteins contain multiple protein-binding domains and are involved in cell junction organization, tumor suppression, and signaling. The MAGUK family is divided into four subfamilies: DLG-like, ZO1-like, p55-like and LIN2-like. MPP7 (MAGUK p55 subfamily member 7), also known as palmitoylated membrane protein 7, is a 576 amino acid protein that belongs to the MAGUK family and assists in the assembly of protein complexes. A peripheral membrane protein that exists as a heterodimer, MPP7 enhances tight junction formation and epithelial cell polarity. MPP7 contains one SH3 domain, a guanylate kinase-like domain, two L27 domains and a single PDZ (DHR) domain. The gene encoding MPP7 maps to human chromosome 10p11.23