Anti-(P)RR antibodies are used in antigen-specific immunodetection in biological samples. The target (P)RR is a known alias name of the protein nuclear receptor subfamily 1 group I member 2, encoded by the NR1I2 gene in humans. This 434-amino acid residue protein is reported to be a nuclear receptor that binds and is activated by variety of endogenous and xenobiotic compounds. It is localized to the nucleus of the cell. In terms of tissue expression, it is reported to be expressed in the liver, colon and small intestine. Other synonyms for (P)RR include BXR, ONR1, and PAR.