CKII is an alias for the gene, Casein kinase 2, alpha 1 polypeptide, in humans. Other names include: Casein kinase II subunit alpha; CK II alpha; CK2A1; CSNK2A3. The encoded protein is an enzyme with an amino acid length of 391 and a mass of 45.1 kDa. CKII is a member of the Protein kinase superfamily, Ser/Thr protein kinase family, CK2 subfamily. This gene shares homology with other species, including: Fly.