Mating-driven variability in olfactory local interneuron wiring

Variations in neuronal connectivity occur widely in nervous systems from invertebrates to mammals. unclear how neuronal variability originates, to what extent and at what time scales it exists, and what functional consequences it might carry. To assess inter- and intraindividual neuronal variability, it would be ideal to analyze the same identified neuron across different brain hemispheres and individuals. Here, using genetic labeling and electron microscopy connectomics, we show that an identified inhibitory olfactory local interneuron, TC-LN, exhibits extraordinary variability in its glomerular innervation patterns. Moreover, TC-LN's innervation of the VL2a glomerulus, which processes food signals and modulates mating behavior, is sexually dimorphic, is influenced by female's courtship experience, and correlates with food intake in mated females. Mating also affects output connectivity of TC-LN to specific local interneurons. We propose that mating-associated variability of TC-LNs regulates how food odor is interpreted by an inhibitory network to modulate feeding.

Automated summary

In this study, the authors used genetic labeling and electron microscopy connectomics to investigate the variability of a specific neuron, TC-LN, in its innervation patterns. They found that this neuron exhibits extraordinary variability and that it is influenced by factors such as sex, courtship experience, and mating in relation to food intake. The researchers propose that this mating-associated variability regulates how food odor is interpreted by the inhibitory network to modulate feeding behavior.