Anti-protein phosphatase 2A regulatory subunit 4 antibodies are used in antigen-specific immunodetection in biological samples. The target protein phosphatase 2A regulatory subunit 4 is a known alias name of the protein protein phosphatase 2 phosphatase activator, encoded by the PTPA gene in humans. This 358-amino acid residue protein is known to be involved in the regulation of apoptosis, among other biological processes. It is localized to the nucleus and cytoplasm of the cell. In terms of tissue expression, it is widely expressed across many tissue types. Other synonyms for protein phosphatase 2A regulatory subunit 4 include PP2A, PPP2R4, and PR53.