To explore possible effects of increased PTEN in the PFC on depression-like behaviors, we injected Cre-dependent PTEN-overexpressing AAV (AAV2/8-DIO-tdTomato-PTEN) or control virus (AAV2/8-DIO-tdTomato) into the PFC of Emx1-Cre mice (Fig. 3a). Here, PTEN is linked to major depressive disorder.