FOS and fungal infectious disease: PI3K/Akt inhibition had no effect on IκBα, phospho-c-Jun, or MKP1 phosphorylation or c-Fos production at 30 minutes or 2 hours (Figure 4E and 4F), indicating that NF-κB and MAPK signaling is independent of PI3K/Akt signaling in response to fungal infection.