IL-3 regulates cell growth by affecting various processes such as cell death, survival and proliferation. Cues from the external environment are sensed by surface receptors, and complex signaling mechanisms within the cells lead to specific functional outcomes. In this study we demonstrate that the cytokine IL-3 induces the activation of the Ca++ dependent phosphatase, calcineurin (Cn). Furthermore Cn functions in turn to dephosphorylate Gab2 resulting in c-fos activation and cell proliferation. We also report that there is a direct interaction between Cn and Gab2 upon IL-3 stimulation, and Akt can regulate this interaction.