genome-wide studies begin to illustrate the potent regulatory control drugs of abuse have on gene activity in the NAc, as numerous genes are up- or down-regulated in response to chronic drug exposure. While much is known about the upstream signaling mechanisms initiated by drug-induced increases in dopamine and other neurotransmitters in the NAc [1–4], far less is known about the downstream mechanisms which integrate neurotransmitter signaling into long-lasting genome-wide alterations in transcription.
