Ready-to-use ELISA kits are available for the detection of FBJ osteosarcoma oncogene B, an alias of the protein, FosB proto-oncogene, AP-1 transcription factor subunit. The official gene symbol is FOSB. The protein, with a mass of 35.9 kDa and length of 338 residues, is reported to be nuclear. It is a member of the BZIP family, Fos subfamily and may be known by other names, including: GOSB, GOS3, G0/G1 switch regulatory protein 3, FosB proto-oncogene AP-1 trancription factor subunit, FBJ murine osteosarcoma viral oncogene homolog B, and protein fosB.