Anti-F-box protein 9 antibodies are used in the immunodetection of the protein encoded by the FBXO9 gene. In humans, the canonical protein has a reported length of 447 amino acid residues and a mass of 52.3 kDa. Its subcellular localization is in the cytoplasm. Alternative splicing is reported to yield 3 different isoforms for this protein. It is reported to be a substrate recognition component of a SCF (SKP1-CUL1-F-box protein) E3 ubiquitin-protein ligase complex which mediates the ubiquitination and subsequent proteasomal degradation of target proteins and plays a role in several biological processes such as cell cycle, cell proliferation, or maintenance of chromosome stability. Other names for this target antigen include NY-REN-57, VCIA1, dJ341E18.2, F-box only protein 9, F-box protein Fbx9, and FBX9.