Table 2.

Residual activity of CK1δ wild type or mutants after treatment with CK1-specific inhibitors.

CK1δ Variant	Bischof-5	Richter-2	IWP-2	IWP-4
WT	50 ± 17	50 ± 15	50 ± 6	50 ± 6
A36V	43 ± 15	109 ± 33	55 ± 6	49 ± 7
R115H	36 ± 10	211 ± 79	71 ± 34	46 ± 5
R127L	50 ± 11	88 ± 34	42 ± 9	48 ± 10
R127Q	24 ± 8	19 ± 2	37 ± 5	36 ± 11
R168H	30 ± 16	31 ± 16	50 ± 9	61 ± 19
R299Q	64 ± 22	69 ± 17	36 ± 20	91 ± 60
Q399*	75 ± 30	50 ± 14	53 ± 27	96 ± 79

Kinase activity of CK1δ^WT and mutants was tested in presence of the CK1-specific inhibitors Bischof-5, Richter-2, IWP-2, and IWP-4, which were used in the IC₅₀ concentration previously determined for CK1δ^WT [14,15,17]. Residual activity is presented as normalized values using the respective DMSO control as a reference (100%). Values were adjusted in order to obtain half-maximal inhibition values for CK1δ^WT (IC₅₀; 50%). Data is represented as mean values ± SD of normalized triplicates. Residual kinase activities lower than 50% are highlighted in bold. Abbreviations: A, alanine; V, valine; R, arginine; H, histidine; L, leucine; Q, glutamine; WT, wild type; *, stop codon.