Anti-prokineticin 2 antibodies are used in the immunodetection of the protein encoded by the PROK2 gene. In humans, the canonical protein has a reported length of 129 amino acid residues and a mass of 14.3 kDa. It is known to be a secreted protein. Alternative splicing is reported to yield 2 different isoforms for this protein. It is reported to be expressed in the testis and, at low levels, in the small intestine. A member of the AVIT (prokineticin) protein family, it is believed to function as a an output molecule from the suprachiasmatic nucleus (SCN) that transmits behavioral circadian rhythm. Other names for this target antigen include protein Bv8 homolog.