Anti-biogenesis of ribosomes BRX1 antibodies are used for the immunodetection of the protein encoded by the BRIX1 gene. In humans, the canonical protein has a reported length of 353 amino acid residues and a mass of 41.4 kDa. Its subcellular localization is in the nucleus. A member of the BRX1 protein family, it is known to be required for biogenesis of the 60S ribosomal subunit. Other names for this target antigen include BXDC2, ribosome biogenesis protein BRX1 homolog, BRX1, biogenesis of ribosomes, homolog, brix domain containing 2, brix domain-containing protein 2, and BRIX. Gene orthologs have been identified in the mouse, rat, bovine, frog, zebrafish, chimpanzee and chicken species.