Anti-MAGUK p55 scaffold protein 4 antibodies are used for the immunodetection of the protein encoded by the MPP4 gene. In humans, the canonical protein has a reported length of 637 amino acid residues and a mass of 72.8 kDa. Its subcellular localization is in the cytoplasm. Alternative splicing is reported to yield 5 different isoforms for this protein. It is reported to be expressed in the retina. A member of the MAGUK protein family, it is believed to play a role in retinal photoreceptors development. Other names for this target antigen include amyotrophic lateral sclerosis 2 chromosomal region candidate gene 5 protein, discs large homolog 6, membrane palmitoylated protein 4, and MAGUK p55 subfamily member 4. Gene orthologs have been identified in the mouse, rat, bovine, frog, chimpanzee and chicken species.