The p85 Regulatory Subunit of PI3K Mediates cAMP-PKA and Insulin Biological Effects on MCF-7 Cell Growth and Motility
Figure 3
Phosphorylation of S83 modulates postreceptorial transduction. MCF-7 cells were transiently transfected with a construct containing p85WT or its S83 mutated forms and treated with 10 nM insulin for 5, 10, or 15 min. AKT (a) and Erk1/2 (b) phosphorylation were determined through Western blot experiments with antibodies against AKT, phosphorylated AKT (Ser473), Erk1/2, and phosphorylated Erk1/2 (Thr202/Tyr204; D13.14.4E). The histograms in the lower panel (c) show the densitometric analysis of the P-AKT/AKT and P-Erk/Erk ratio relative to -actin, derived from three independent experiments performed in triplicate (). Differences between treatments were tested for statistical significance using Student’s matched pairs -test: compared to the untransfected cells (same treatment, same time). Transfection efficiency was monitored by measuring the GFP expression (see Section 2) and only transfection with efficiency higher 55% was taken (Figure S3A).
