Anti-SEM1 26S proteasome subunit antibodies are used for the immunodetection of the protein encoded by the SEM1 gene. In humans, the canonical protein has a reported length of 70 amino acid residues and a mass of 8.3 kDa. Its subcellular localization is in the nucleus. It is reported to be expressed in limb bud, craniofacial primordia and skin. A member of the DSS1/SEM1 protein family, it is a known component of the 26S proteasome, a multiprotein complex involved in the ATP-dependent degradation of ubiquitinated proteins. Other names for this target antigen include DSS1, ECD, PSMD15, SHFD1, SHFM1, SHSF1, Shfdg1, and C7orf76. Gene orthologs have been identified in the mouse, rat, bovine, frog, zebrafish, chimpanzee and chicken species.