Anti-FAM3 metabolism regulating signaling molecule B antibodies are used for the immunodetection of the protein encoded by the FAM3B gene. In humans, the canonical protein has a reported length of 235 amino acid residues and a mass of 26 kDa. It is known to be a secreted protein. Alternative splicing is reported to yield 3 different isoforms for this protein. It is reported to be highly expressed in the pancreas. A member of the FAM3 protein family, it is known to be involved with the apoptotic pathway. Post-translational modifications have been described, including O-glycosylation and protein cleavage. Other names for this target antigen include C21orf11, C21orf76, ORF9, PANDER, PRED44, protein FAM3B, D21M16SJHU19e, and 2-21. Gene orthologs have been identified in the mouse, rat, bovine, frog, chimpanzee and chicken species.