FIG. 4.

Phosphorylation of Axil by GSK-3β. (A) Autoradiography. Myc-Axil immunoprecipitated from COS cell lysates (250 μg of protein) was incubated with (lane 2) or without (lane 1) GST–GSK-3β (100 ng of protein) for 20 min, and the samples were subjected to SDS-PAGE followed by autoradiography. The arrow and arrowhead indicate the positions of Myc-Axil and GST–GSK-3β, respectively. (B) Time course. Myc-Axil immunoprecipitated from COS cell lysates was incubated with (•) or without (○) GST–GSK-3β (100 ng of protein) for the indicated periods of time. (C) Dose dependency. Myc-Axil was incubated with the indicated amounts of GST–GSK-3β for 20 min. The results shown are representative of four independent experiments.