Anti-PP4R4 antibodies enable researchers to detect and measure the PP4R4 antigen in biological samples. This target is a reported synonym of the PPP4R4 gene, which encodes protein phosphatase 4 regulatory subunit 4. This protein is believed to be a regulatory subunit of serine/threonine-protein phosphatase 4. The human version of PP4R4 has a canonical amino acid length of 873 residues and a protein mass of 99.5 kilodaltons, although 2 isoforms have been identified. It is reported to be localized in the cytoplasm of cells and notably expressed in the cerebral cortex, cerebellum, and caudate.