Anti-MAGUK p55 scaffold protein 1 antibodies are used for the immunodetection of the protein encoded by the MPP1 gene. In humans, the canonical protein has a reported length of 466 amino acid residues and a mass of 52.3 kDa. Its subcellular localization is in the cell membrane. Alternative splicing is reported to yield 3 different isoforms for this protein. It is ubiquitously expressed across many tissue types. A member of the MAGUK protein family, it is a reported essential regulator of neutrophil polarity. Post-translational modifications have been described, including palmitoylation. Other names for this target antigen include DXS552E, EMP55, MRG1, PEMP, 55 kDa erythrocyte membrane protein, and AAG12. Gene orthologs have been identified in the mouse, rat, bovine, frog, zebrafish, chimpanzee and chicken species.