FERM domains are roughly 150 amino acids in length and are found in a number of cytoskeletal-associated proteins such as Ezrin, Radixin, Moesin and 4.1 (erythrocyte membrane protein band 4.1), where they provide a link between cytoskeletal signals and membrane dynamics. EPB41L5 (erythrocyte membrane protein band 4.1 like 5), also known as BE37 or YMO1, is a 733 amino acid cytoplasmic protein that contains one FERM domain, which it uses to bind CRB1 (crumbs homolog 1). EPB41L5 is a homolog of zebrafish 'mosaic eyes' (moe), and is widely expressed but found at highest levels in ovary, kidney and brain, and is known to colocalize with β-catenin. EPB41L5 may participate in tight junction positioning during the establishment of epithelial cell polarity, and exists as four alternatively spliced isoforms that are encoded by a gene located on human chromosome 2q14.2.