Genes that influence dopamine and adrenaline originated 650 million years ago

To fill that gap, a team of scientists at the University of Leicester in England has discovered that the genes required for these complex behaviors originated around 650 million years ago.

Genes required for the production of monoamines

Dr. Roberta Feuda, who led the research and was the lead author of the study, explained that there has been uncertainty around the origin of the genes required for the production, detection, and degradation of monoamines.

The research group studies the pattern of duplication of 18 genes encoded in the proteins involved in the synthesis, turnover, and detection of monoamines.

“Using the computational methods, we reconstructed the evolutionary history of these genes and show that most of the genes involved in monoamine production, modulation, and reception originated in the bilaterian stem group,” she said, in an official release.

Genes evolved about 650 million years ago

Their discovery suggests that the monoaminergic system evolved within the span of the end of the Cryogenian period to the beginning of the Ediacaran period, about 650−600 million years ago. At the end of the Ediacaran period, the oceans experienced an increase in oxygen concentration. This change brought on the emergence of more energetically intensive and complex modes of life. The origin of the monoaminergic system during this period, such as providing flexibility of the neural circuits to facilitate the interaction with the environment, is evident in the fossil record, noted the study.

Dr. Feuda added, “This discovery will open new important research avenues that will clarify the origin of complex behaviors and if the same neurons modulate reward, addiction, aggression, feeding, and sleep.”

The study was published in Nature Communications.

Study abstract:

Monoamines like serotonin, dopamine, and adrenaline/noradrenaline (epinephrine/norepinephrine) act as neuromodulators in the nervous system. They play a role in complex behaviors, cognitive functions such as learning and memory formation, as well as fundamental homeostatic processes such as sleep and feeding. However, the evolutionary origin of the genes required for monoaminergic modulation is uncertain. Using a phylogenomic approach, in this study, we show that most of the genes involved in monoamine production, modulation, and reception originated in the bilaterian stem group. This suggests that the monoaminergic system is a bilaterian novelty and that its evolution may have contributed to the Cambrian diversification.