sentences:  Associated with a connection to mood disorders, NPAS2 has been found to be involved with dopamine degradation.This was first suggested by the observation that the clock components BMAL1 and NPAS2 transcriptionally activated a luciferase reporter driven by the murine monoamine oxidase A ("Maoa") promoter in a circadian fashion.This suggested that these two clock components (BMAL1 and NPAS2) directly regulated "Maoa" transcription.