TY - JOUR TI - Local synaptic inputs support opposing, network-specific odor representations in a widely projecting modulatory neuron AU - Zhang, Xiaonan AU - Coates, Kaylynn AU - Dacks, Andrew AU - Günay, Cengiz AU - Lauritzen, J Scott AU - Li, Feng AU - Calle-Schuler, Steven A AU - Bock, Davi AU - Gaudry, Quentin A2 - Ramaswami, Mani A2 - Calabrese, Ronald L A2 - Ramaswami, Mani A2 - Raman, Baranidharan VL - 8 PY - 2019 DA - 2019/07/02 SP - e46839 C1 - eLife 2019;8:e46839 DO - 10.7554/eLife.46839 UR - https://doi.org/10.7554/eLife.46839 AB - Serotonin plays different roles across networks within the same sensory modality. Previously, we used whole-cell electrophysiology in Drosophila to show that serotonergic neurons innervating the first olfactory relay are inhibited by odorants (Zhang and Gaudry, 2016). Here we show that network-spanning serotonergic neurons segregate information about stimulus features, odor intensity and identity, by using opposing coding schemes in different olfactory neuropil. A pair of serotonergic neurons (the CSDns) innervate the antennal lobe and lateral horn, which are first and second order neuropils. CSDn processes in the antennal lobe are inhibited by odors in an identity independent manner. In the lateral horn, CSDn processes are excited in an odor identity dependent manner. Using functional imaging, modeling, and EM reconstruction, we demonstrate that antennal lobe derived inhibition arises from local GABAergic inputs and acts as a means of gain control on branch-specific inputs that the CSDns receive within the lateral horn. KW - neuromodulation KW - olfaction KW - serotonin KW - Drosophila KW - dendrite KW - compartmental model JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -