Figure 8. FINDY selectively inhibits DYRK1A.

(a,b) Recombinant DYRK1B (a) and DYRK2 (b) were incubated with the peptide substrate DYRKtide in the presence of FINDY, RD0392 or INDY. RD0392 and INDY inhibit the kinase activity with IC₅₀ values of 53.3 and 69.2 nM, respectively, for DYRK1B, and with IC₅₀ values of 45.6 and 27.7 nM, respectively, for DYRK2. The results are presented as means±s.d. (n=4). (c,d) Bicistronic expression of FLAG-DYRK1B (c) and FLAG-DYRK2 (d) with EGFP in HEK293 cells. FINDY administered at the indicated concentrations (Conc.) did not affect the expression of FLAG-DYRK1B and FLAG-DYRK2. Representative data from the triplicate experiments are shown. (e) Intact HEK293 cells were cultured in the presence of FINDY for 3 days. The indicated kinases and GAPDH were detected by western blot analysis using the corresponding antibodies. The categories of the indicated kinases in the kinome are shown. Representative data from the duplicate experiments are shown.