Fig. 3. SGK is not regulated by cAMP. Top, MDCK cells were transfected with wild-type, Thr369A mutant or S422D mutant SGK and cells were stimulated with 1 mM cAMP analog before SGK1 activity was measured. Kinase assay was carried out as described in the Materials and Methods. Bottom. The cell extracts were probed for phosphorylated CREB to verify cAMP stimulation and probed with anti-HA to determine the amount of HA-SGK in the kinase assay.