Anti-crumbs cell polarity complex component 3 antibodies are used for the immunodetection of the protein encoded by the CRB3 gene. In humans, the canonical protein has a reported length of 120 amino acid residues and a mass of 12.9 kDa. Its subcellular localization is in the cell membrane. Alternative splicing is reported to yield 2 different isoforms for this protein. It is found to be highly expressed in epithelial tissues. It is reported to be involved in establishment of cell polarity in mammalian epithelial cells. Post-translational modifications have been described, including glycosylation. Other names for this target antigen include crumbs 3, cell polarity complex component, crumbs family member 3, and protein crumbs homolog 3. Gene orthologs have been identified in the mouse, rat, bovine, frog and chimpanzee species.