Fig. 4. SGK activation does not correlate with membrane translocation. (A) GFP-SGK1 is a kinase-active protein. MDCK cells were transfected with empty vector (GFP) or GFP-SGK1 (SGKwt) and stimulated by HGF for 15 minutes. Kinase activity was determined as described in the Materials and Methods. The lower insert depicts the amount of GFP-SGK present in the assay. (B) MDCK cells were transfected with GFP, GFP-SGK or GFP-PH/AKT (the pleckstrin homology domain of AKT) and stimulated with HGF for 15 minutes. A parallel cotransfection experiment between the above vectors and RacV12 is also shown. After fixing the cells, the location of the GFP derivatives was determined by confocal microscopy as described in the Materials and Methods.