title: Parallel pathways convey olfactory information with opposite polarities in Drosophila.
abstract: In insects, olfactory information received by peripheral olfactory receptor neurons (ORNs) is conveyed from the antennal lobes (ALs) to higher brain regions by olfactory projection neurons (PNs). Despite the knowledge that multiple types of PNs exist, little is known about how these different neuronal pathways work cooperatively. Here we studied the Drosophila GABAergic mediolateral antennocerebral tract PNs (mlPNs), which link ipsilateral AL and lateral horn (LH), in comparison with the cholinergic medial tract PNs (mPNs). We examined the connectivity of mlPNs in ALs and found that most mlPNs received inputs from both ORNs and mPNs and participated in AL network function by forming gap junctions with other AL neurons. Meanwhile, mlPNs might innervate LH neurons downstream of mPNs, exerting a feedforward inhibition. Using dual-color calcium imaging, which enables a simultaneous monitoring of neural activities in two groups of PNs, we found that mlPNs exhibited robust odor responses overlapping with, but broader than, those of mPNs. Moreover, preferentially down-regulation of GABA in most mlPNs caused abnormal courtship and aggressive behaviors in male flies. These findings demonstrate that in Drosophila, olfactory information in opposite polarities are carried coordinately by two parallel and interacted pathways, which could be essential for appropriate behaviors.
authors: Institute of Neuroscience and State Key Laboratory of Neuroscience, Shanghai Institutes for Biological Sciences, Shanghai 200031, China.
authors: Kaiyu
authors: K
authors: Wang
authors: Jiaxin
authors: J
authors: Gong
authors: Qingxiu
authors: Q
authors: Wang
authors: Hao
authors: H
authors: Li
authors: Qi
authors: Q
authors: Cheng
authors: Yafeng
authors: Y
authors: Liu
authors: Shaoqun
authors: S
authors: Zeng
authors: Zuoren
authors: Z
authors: Wang
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D001921:Brain / Q000502:physiology*; D063132:Connectome; D003433:Crosses, Genetic; D004330:Drosophila / Q000502:physiology*; D059330:GABAergic Neurons / Q000502:physiology; D018613:Microscopy, Confocal; D008959:Models, Neurological; D055696:Olfactory Perception / Q000502:physiology*; D018034:Olfactory Receptor Neurons / Q000502:physiology*; D062308:Optogenetics; D018408:Patch-Clamp Techniques; D012726:Sexual Behavior, Animal / Q000502:physiology*; D018709:Statistics, Nonparametric; D013268:Stimulation, Chemical; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
chemical_list: D005680:gamma-Aminobutyric Acid
keywords: circuit; electrical coupling; electrophysiology; multicolor calcium imaging; multiglomerular