Figure 8.
Recombinant HIPK3 recognizes Runx2 AD3 peptide as a kinase substrate. A, A synthetic peptide encompassing the unique Runx2 AD3 residues contributing to Runx1:Runx2(316-421) chimera response to MINT+FGF2 was tested as a substrate for phosphorylation by HIPK3. A control peptide lacking proline-directed kinase cognates served as a control for background. WT Runx2 AD3 is phosphorylated to a significant extent above background by HIPK3. *, P < 0.05 vs. mutant; **, P < 0.01 vs. mutant. B, DMAT inhibits HIPK3-dependent phosphorylation of Runx2 AD3, with an IC50 that is about 100-fold lower than that of the potent CK2 inhibitor, emodin. NS, Not significant.