Provided below are ELISA kits targeting testis specific serine kinase substrate, a human protein encoded by TSKS. This protein is 592 amino acids long with a reported mass of 65.1 kDa. 2 isoforms have been identified. This is reported to be a cytoplasmic protein. Other alias names for this protein include: STK22 substrate 1, protein phosphatase 1 regulatory subunit 161, testis specific serine/threonine kinase substrate, testis-specific kinase substrate, STK22S1, TSKS1, and TSSKS.