Figure 9.

Schematic illustration of the mechanisms by which Akt promotes the nuclear accumulation and prevents cytosolic translocation of LKB1. Left panel: Activated Akt phosphorylates LKB1 at Ser334 and induces phosphorylation-dependent association with 14-3-3 proteins, which block STRADα binding and lead to the nuclear retention of LKB1. Right panel: When Akt is inactive, LKB1 binds to STRADα, which promotes the cytoplasmic translocation of LKB1 and enhances the tumor suppressor activity of this kinase.