SLC6A4 binding site and acute prosocial effects of (+/-)-3,4-methylendioxymethamphetamine (MDMA) are evolutionarily conserved in Octopus bimaculoides

Summary

MDMA enhances acute prosocial behaviors in the octopus species Octopus bimaculoides, similar to effects observed in humans. This suggests that despite evolutionary differences, certain neural mechanisms for social behavior are conserved across species. The study also identifies that the serotonin transporter binding site for MDMA is present in the O. bimaculoides genome, indicating a shared evolutionary role of serotonergic neurotransmission in regulating social behaviors.

Study at a glance

Abstract

Human and octopus lineages are separated by over 500 million years of evolution, and show divergent anatomical patterns of brain organization. Moreover, while humans exhibit highly complex social behaviors, octopuses are thought to be largely asocial and solitary. Despite these differences, growing evidence suggests that ancient neurotransmitter systems are shared across vertebrate and invertebrate species, and in many cases enable overlapping functions. Here we provide evidence that, as in humans, the atypical amphetamine derivative (+/-)-3,4-methylendioxymethamphetamine (MDMA) enhances acute prosocial behaviors in Octopus bimaculoides. This finding is paralleled by the evolutionary conservation of the serotonin transporter (SERT, encoded by the Slc6A4 gene) binding site of MDMA in the O. bimaculoides genome. Taken together, these data provide evidence that the neural mechanisms subserving social behaviors exist in O. bimaculoides, and indicate that the role of serotonergic neurotransmission in regulating social behaviors is evolutionarily conserved.