Anti-SOX3 antibodies are used in the immunodetection of the protein SRY-box transcription factor 3. In humans, the canonical protein has a reported length of 446 amino acid residues and a mass of 45.2 kDa. Its subcellular localization is in the nucleus. SOX3 is known to be a transcription factor required during the formation of the hypothalamo-pituitary axis. Synonyms for this target antigen include MRGH, PHP, PHPX, SOXB, transcription factor SOX-3, SRY (sex determining region Y)-box 3, SRY-box 3, and GHDX.