Anti-exportin 1 antibodies are used in the immunodetection of the protein encoded by the XPO1 gene. In humans, the canonical protein has a reported length of 1071 amino acid residues and a mass of 123.4 kDa. Its subcellular localization is in the nucleus and cytoplasm. It is found to be expressed in heart, brain, placenta, lung, liver, skeletal muscle, pancreas, spleen, thymus, prostate, testis, ovary, small intestine, colon and peripheral blood leukocytes. A member of the Exportin protein family, it is known to mediate the nuclear export of cellular proteins (cargos) bearing a leucine-rich nuclear export signal (NES) and of RNAs. Other names for this target antigen include CRM1, emb, exp1, chromosome region maintenance 1 homolog, chromosome region maintenance 1 protein homolog, and CRM-1.