(E) Bead-immobilized in vitro translated (IVT) HA-SOX9 wild type (WT) or T236/240 mutant were either untreated or subjected to in vitro GSK3 kinase reaction for 90 minutes at 37◦C prior to elution and gel electrophoresis. The SOX9 blot showed total SOX9 protein eluted from the beads from each reaction. Shown immunoblots are single representative experiment from 3 independent repeats. 