Anti-JK1 antibodies enable researchers to detect and measure the JK1 antigen in biological samples. This target is a reported synonym of the RETREG1 gene, which encodes reticulophagy regulator 1. This protein is known to function in the regulation of apoptosis and white fat cell differentiation, among other biological roles. The human version of JK1 has a canonical amino acid length of 497 residues and a protein mass of 54.7 kilodaltons, although 2 isoforms have been identified. It is reported to be localized in the ER and Golgi of cells. JK1 is a member of the RETREG protein family.