AKT1 and cocaine dependence: KEGG annotation revealed that mRNAs differentially expressed in the mutant mouse cerebrum were enriched in a number of signaling pathways including tyrosine metabolism, transcriptional mis-regulation in cancer, thyroid cancer, serotonergic synapse, retrograde endocannabinoid signaling, PI3K-Akt signaling, Parkinson’s disease, nicotine addiction, neuro-active ligand-receptor interaction, morphine addiction, dopaminergic synapse, cocaine addiction, circadian entrainment, cholinergic synapse, cAMP signaling, calcium signaling, amphetamine addition, and alcoholism (Figure 3b).