Anti-symplekin scaffold protein antibodies are used for the immunodetection of the protein encoded by the SYMPK gene. In humans, the canonical protein has a reported length of 1274 amino acid residues and a mass of 141.1 kDa. Its subcellular localization is in the cell membrane, nucleus, and cytoplasm. Alternative splicing is reported to yield 2 different isoforms for this protein. A member of the Symplekin protein family, it is reported to be a scaffold protein that functions as a component of a multimolecular complex involved in histone mRNA 3'-end processing. Other names for this target antigen include SPK, SYM, symplekin, and Pta1. Gene orthologs have been identified in the mouse, rat, bovine, frog, zebrafish and chimpanzee species.