To put it plainly, the discovery that monoamine neurotransmitters control epigenetic regulation of genes is transformative for basic science and medicine

To test that hypothesis, the researchers genetically modified H3 histones in rats by replacing the amino acid that dopamine attaches to with a different one it doesn’t react with. This stops dopaminylation from occurring. Withdrawal from cocaine is associated with changes in the readout of hundreds of genes involved in rewiring neural circuits and altering synaptic connections, but in the rats whose dopaminylation was prevented, these changes were suppressed. Moreover, neural impulse firing in VTA neurons was reduced, and they released less dopamine, showing that these genetic changes were indeed affecting the brain’s reward circuit operation. This might account for why people with substance use disorder crave drugs that boost dopamine levels in the brain during withdrawal. Finally, in subsequent tests, the genetically modified rats exhibited much less cocaine-seeking behavior

dopaminylation. The term refers to the brain chemical dopamine’s ability, in addition to transmitting signals across synapses, to enter a cell’s nucleus and control specific genes