Levy, S. et al. Nat Ecol Evol https://doi.org/10.1038/s41559-020-01338-3 (2020)
Mammals got to have their GABA. The inhibitory neurotransmitter plays an important role during embryonic development and influences neuronal differentiation and stem proliferation in the adult brain. GABA turns up outside mammalian lineages as well and has been studied in model organisms from fruit flies and C. elegans worms to a member of one the earliest evolutionary branches in the animal kingdom: the sea anemone Nematostella vectensis.
A new study from researchers at the University of Haifa in Israel finds four likely homologues of GABAb, one of two GABA receptors found in the nervous system. The anemone doesn’t have a brain per se—rather, a nerve net—but activating the receptors inhibited neurogenesis and prevented metamorphosis. These results suggest an evolutionarily conserved role for the neurotransmitter and that Nematostella may be a valuable model system to study GABA signaling.