Anti-FRK antibodies are used in the immunodetection of the protein fyn related Src family tyrosine kinase. In humans, the canonical protein has a reported length of 505 amino acid residues and a mass of 58.3 kDa. Its subcellular localization is in the nucleus and cytoplasm. Up to 2 different isoforms have been reported for this protein. It is reported to be highly expressed in the epithelial derived cell lines and tissues, especially normal liver, kidney, breast and colon. A member of the Tyr protein kinase protein family, FRK is known to be involved with cell differentiation and innate immune responses. Synonyms for this target antigen include PTK5, RAK, tyrosine-protein kinase FRK, PTK5 protein tyrosine kinase 5, fyn-related kinase, and GTK. FRK gene orthologs have been reported in the mouse, rat, bovine, frog, zebrafish, chimpanzee and chicken species. Some FRK antibodies may have been used in research and have associated citations. Western Blot is a widely used application for these antibodies. ELISA, Immunofluorescence, and Immunohistochemistry are also common applications.