Wed. 5/22 Biology Seminar, 1:15 pm - Meghan Lockhard

Meghan Lockard (Rockefeller University): “La Dolce Verma: Oxytocin, Dopamine, and their Role as Comodulators in Nematode Nooky”, 1:15 -2:15 pm, Rm. 926HN

Oxytocin has been known to the biomedical community for 150 years as being a regulator of complex reproductive behavior and physiological processes in mammals and other vertebrates, but evolutionary the neuropeptide emerged in metazoans about 700 million years ago, around the same time as bilateral symmetry. In every instance where it has been studied, from nematodes to humans, oxytocin homologs have been shown to play a role in mate search, mating, and/or provisioning of offspring. What is the basis for this genetic and functional conservation?  To address this, I looked at the functional role of oxytocin in modulating the mating circuit of the nematode C. elegans. Like its mammalian homolog, nematocin comodulates mating behavior with the nonclassical neurotrasmitter dopamine. Through genetics, neuronal imaging, and circuit manipulation, I show how the timing and levels of nematocin release are critical for the male to mate with coherence and momentum. Dopamine couples this release with specific stimuli from mating via the antagonism between a D1-like and a D2-like receptor expressed in the same nematocin releasing neuron, DVA.  The circuit serves as a model for how a simple, highly conserved repertoire of neuromodulators could generate some of nature's richest and most complex behaviors.