PT  - JOURNAL ARTICLE
AU  - Philipp Schlegel
AU  - Michael J Texada
AU  - Anton Miroschnikow
AU  - Marc Peters
AU  - Casey M Schneider-Mizell
AU  - Haluk Lacin
AU  - Feng Li
AU  - Richard D Fetter
AU  - James W Truman
AU  - Albert Cardona
AU  - Michael J Pankratz
TI  - Neuromedin U-homolog Microcircuit Connects Chemosensory and Neuroendocrine Systems in <em>Drosophila</em>
AID  - 10.1101/044990
DP  - 2016 Jan 01
TA  - bioRxiv
PG  - 044990
4099  - http://biorxiv.org/content/early/2016/03/21/044990.short
4100  - http://biorxiv.org/content/early/2016/03/21/044990.full
AB  - Neuromedin U (NMU) is a potent regulator of food intake and activity in mammals. While some downstream targets of NMU have been localized, connectivity of the neural circuits employing this neuropeptide is largely unknown. In Drosophila, neurons producing the homologous neuropeptide hugin regulate feeding and locomotion in a similar manner and project to structures of the central nervous system analogous to those in which NMU is found. Here, we use EM reconstruction and receptor expression analysis to map the connectome of hugin-producing neurons in the Drosophila larval central nervous system. We show that hugin-producing neurons establish distinct units that are reciprocally connected and share connectivity motifs. One of these units simultaneously employs synaptic as well as peptide-receptor connections to target neuroendocrine cells (NSCs) of the pars intercerebralis, the Drosophila analog of the hypothalamus. These NSCs produce CRH- and insulin-like peptides which are homologs of downstream targets of NMU. Furthermore, most of the hugin-producing neurons, including those that target the NSCs, receive inputs from chemosensory neurons in the subesophageal zone, the brain stem analog in Drosophila. Our data positions hugin neurons as part of a novel sensory-to-endocrine network that may reflect the way NMU operates in mammals. We propose that the hugin neurons interconnecting chemosensory and neuroendocrine organs are part of a physiological control system that has been conserved not only at functional and molecular levels, but at the network architecture level as well.