In mammals, 7 distinct genes encoding CK1 isoforms (CK1 alpha, CK1 beta, CK1 gamma1, CK1 gamma2, CK1 gamma3, CK1 delta and CK1 epsilon) are expressed which differ mainly in length and primary structure of the C-terminal non-catalytic domain. Furthermore, CK1 alpha splice variants have been detected in many different organisms including vertebrates and mammals. Alternative splicing leads to the ...