CTCL-associated antigen HD-CL-09 is an alias for the gene, TAO kinase 3, in humans. Other names include: Serine/threonine-protein kinase TAO3; Dendritic cell-derived protein kinase; JNK/SAPK-inhibitory kinase; Jun kinase-inhibitory kinase; Kinase from chicken homolog A; hKFC-A; Thousand and one amino acid protein 3; Cutaneous T-cell lymphoma-associated antigen HD-CL-09; Serine/threonine-protein kinase TAO3 ; JIK; MAP3K18. The encoded protein is an enzyme with an amino acid length of 898 and a mass of 105.4 kDa. Other isoforms may exist. CTCL-associated antigen HD-CL-09 is a member of the Protein kinase superfamily, STE Ser/Thr protein kinase family, STE20 subfamily. This gene shares homology with other species, including: Rat.