Detection of endogenous Casein Kinase 1 epsilon: Whole cell lysates of serum starved tumor cells (20.000 cells per lane) were applied to SDS-PAGE and transferred to a PVDF membrane. The immunoblot was probed with mab CK1e-4D7 (0.5 ug/ ml) for 1h at RT and developed by ECL (exp. time: 30 sec) lane 1: HeLa; lane 2: HepG2; lane 3: HEK293; lane 4: SH-SY5Y; lane 5: MDCK; lane 6: PC12; lane 7: CMT 93; lane 8: Neuro 2A; lane 9: NIH 3T3.