Considering that circFKBP8(5S,6) is exclusively expressed in higher primates, the current study employed an rAAV-mediated overexpression system in the mouse PrL to specifically investigate whether circFKBP8(5S,6)’s effects on depression-like behaviors are mediated through DRD3 and its downstream signaling pathways. Here, DRD3 is linked to major depressive disorder.