Caseine Kinase 1 alpha belongs to the protein kinase superfamily, CK1 Ser/Thr protein kinase family, Casein kinase I subfamily. CK1 isoforms (alpha, beta, gamma, delta, epsilon) and their splice variants are involved in diverse cellular processes including membrane trafficking, circadian rhythm, cell cycle progression, chromosome segregation, apoptosis and cellular differentiation. Perhaps it can phosphorylate a large number of proteins and is involved in Wnt signaling where it phosphorylates CTNNB1 on Ser45. Caseine kinase 1 alpha also interacts with the Axin complex