Taste cells expressingIonotropic Receptor 94ereciprocally impact feeding and egg laying inDrosophila

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 23, 2024

ABSTRACT Chemosensory cells across the body of Drosophila melanogaster evaluate environment and play a crucial role in neural circuits that prioritize feeding, mating, or egg laying. Previous mapping gustatory receptor neurons (GRNs) on fly labellum identified set L-type sensilla defined by expression Ionotropic Receptor 94e (IR94e), but impact IR94e GRNs behavior remained unclear. To understand their behavioral output, we used optogenetics chemogenetics to activate found they drive mild suppression feeding enhanced In vivo calcium imaging revealed respond strongly certain amino acids, including glutamate. Furthermore, is necessary sufficient for detection acid ligands, co-receptors IR25a IR76b are also required GRN activation. Finally, mutants show changes solutions containing increased consumption decreased Overall, our results suggest discourage encourage laying as part an important switch response chemical cues.

Language: Английский

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Functional imaging and connectome analyses reveal organizing principles of taste circuits inDrosophila

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Aug. 26, 2024

Abstract Taste is crucial for many innate and learned behaviors. In the fly, taste impacts feeding, oviposition, locomotion, mating, memory formation, to name a few. These diverse roles may necessitate apparent distributed nature of responses across different circuits in fly brain, leading complexity that has hindered attempts deduce unifying principles processing coding. Here, we combine information from whole brain connectome with functional calcium imaging examine neural representation at early steps processing. We find quality remains largely segregated cholinergic GABAergic local interneurons (LNs) are directly postsynaptic sensory neurons labellum. Although some projection (TPNs) projecting superior protocerebrum receive direct inputs neurons, primarily indirect via LNs. Moreover, found appear function as nodes convey feedforward dedicated sets morphologically similar TPNs. Examining small number representative TPNs suggests mostly this level well. Together, these studies suggest previously unappreciated logic organization circuits.

Language: Английский

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Neural circuit mechanisms underlying context-specific halting inDrosophila

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: Sept. 27, 2023

Abstract Walking is a complex motor program involving coordinated and distributed activity across the brain spinal cord. Halting appropriately at correct time critical but often overlooked component of walking control. While recent studies have delineated specific genetically defined neuronal populations in mouse brainstem that drive different types halting 1–3 , underlying neural circuit mechanisms responsible for overruling competing walking-state to generate context-appropriate halting, remain unclear. Here, we elucidate two fundamental by which Drosophila implement halting. The first mechanism (“walk-OFF” mechanism) relies on GABAergic neurons inhibit descending commands brain, while second (“brake” excitatory cholinergic nerve-cord lead an active arrest stepping movements. Using connectome-informed models 4–6 functional studies, show deploy “walk-OFF” distinct walking-promotion neurons, leading differential forward-walking or steering. “brake” other hand, override all simultaneously inhibiting promoting pathways increasing resistance leg-joints leg movements stance phase walking. We characterized ethologically relevant behavioral contexts were used animal mutually exclusive manner: pathway was engaged during feeding, grooming. Furthermore, this knowledge targets allowed us use connectomics predict novel could be contexts.

Language: Английский

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Overlap and divergence of neural circuits mediating distinct behavioral responses to sugar

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: Oct. 2, 2023

SUMMARY A single sensory cue can elicit diverse behavioral responses. For example, the taste of sugar robustly promotes feeding 1, 2 but also influences other behaviors, such as altering locomotor patterns to maximize food-finding 3, 4 or conferring a rewarding value onto associated contexts cues. 5–7 Here, we investigate how sweet elicits multiple appetitive behaviors in Drosophila . Are different sugar-evoked coordinately regulated? At what point does circuit diverge into pathways that drive distinct behaviors? We first established an optogenetic paradigm study effects on locomotion, spatial preference, and associative learning. then tested were modulated by internal external factors, including hunger, diet, presence aversive taste. Different generally similar ways, observed some differences reveal selective modulation specific pathways. Finally, investigated where diverges recent identified sensory-motor comprising five layers neurons drives initiation response sugar. 8 By individually manipulating each these neurons, show circuits mediating innate responses are partially overlapping begin at level second- third-order whereas for versus learned may synapse. Connectomic analyses subcircuits mediate behaviors. Together, studies provide insight neural organized stimulus.

Language: Английский

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Insect Taste

CABI eBooks, Journal Year: 2024, Volume and Issue: unknown, P. 79 - 93

Published: March 26, 2024

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