Anti-proline-rich acidic protein 1 antibodies enable researchers to detect and measure the proline-rich acidic protein 1 antigen in biological samples. This target is a reported synonym of the PRAP1 gene, which encodes proline rich acidic protein 1. This protein is known to function in DNA damage pathways and the regulation of apoptosis, among other biological roles. The human version of proline-rich acidic protein 1 has a canonical amino acid length of 151 residues and a protein mass of 17.2 kilodaltons, although 4 isoforms have been identified. It is reported to be localized in the ER and is secreted of cells and notably expressed in the small intestine, liver, kidney, duodenum, and appendix.