Endocrine cybernetics: neuropeptides as molecular switches in behavioural decisions

Open Biology, Journal Year: 2022, Volume and Issue: 12(7)

Published: July 1, 2022

Plasticity in animal behaviour relies on the ability to integrate external and internal cues from changing environment hence modulate activity synaptic circuits of brain. This context-dependent neuromodulation is largely based non-synaptic signalling with neuropeptides. Here, we describe select peptidergic systems Drosophila brain that act at different levels a hierarchy associated physiology. These regions, such as central complex mushroom bodies, which supervise specific behaviours. At top level there are small numbers large neurons arborize widely multiple areas orchestrate or global state manner. bottom local provide executive sensory gain intrinsically restricted parts neuronal circuits. The orchestrating receive interoceptive signals mediate energy sleep homeostasis, metabolic circadian timing, well affect food search, aggression mating. Some these can be triggers conflicting behaviours mating versus aggression, feeding, participate circuits, enabling choices switches.

Language: Английский

---

Neural circuits underlying context-dependent competition between defensive actions in Drosophila larvae

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: Jan. 28, 2025

To ensure their survival, animals must be able to respond adaptively threats within environment. However, the precise neural circuit mechanisms that underlie flexible defensive behaviors remain poorly understood. Using neuronal manipulations, machine learning-based behavioral detection, electron microscopy (EM) connectomics and calcium imaging in Drosophila larvae, we map second-order interneurons are differentially involved competition between actions response competing aversive cues. We find mechanosensory stimulation inhibits escape favor of startle by influencing activity escape-promoting interneurons. Stronger activation those neurons startle-like behaviors. This suggests occurs at level Finally, identify a pair descending promote could modulate sequence. Taken together, these results characterize pathways competition, which is modulated sensory context.

Language: Английский

---

From perception to behavior: The neural circuits underlying prey hunting in larval zebrafish

Frontiers in Neural Circuits, Journal Year: 2023, Volume and Issue: 17

Published: Feb. 1, 2023

A key challenge for neural systems is to extract relevant information from the environment and make appropriate behavioral responses. The larval zebrafish offers an exciting opportunity studying these sensing processes sensory-motor transformations. Prey hunting instinctual behavior of that requires brain combine different attributes sensory input form motor outputs. Due its small size transparency allows optical recording whole-brain activity reveal mechanisms involved in prey capture. In this review we discuss how visual identify locate prey, circuits governing generation commands response can be modulated by internal states experience, some outstanding questions field.

Language: Английский

---

Multisite regulation integrates multimodal context in sensory circuits to control persistent behavioral states in C. elegans

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: May 26, 2023

Abstract Maintaining or shifting between behavioral states according to context is essential for animals implement fitness-promoting strategies. How the integration of internal state, past experience and sensory inputs orchestrates persistent multidimensional changes remains poorly understood. Here, we show that C. elegans integrates environmental temperature food availability over different timescales engage in dwelling, scanning, global glocal search strategies matching thermoregulatory feeding needs. Transition states, each case, involves regulating multiple processes including AFD FLP tonic neurons activity, neuropeptide expression downstream circuit responsiveness. State-specific FLP-6 FLP-5 signaling acts on a distributed set inhibitory GPCR(s) promote scanning search, respectively, bypassing dopamine glutamate-dependent state control. Integration multimodal via multisite regulation circuits might represent conserved regulatory logic flexible prioritization valence when operating transitions.

Language: Английский

---

Invertebrates as models of learning and memory: investigating neural and molecular mechanisms

Journal of Experimental Biology, Journal Year: 2023, Volume and Issue: 226(3)

Published: Jan. 31, 2023

In this Commentary, we shed light on the use of invertebrates as model organisms for understanding causal and conserved mechanisms learning memory. We provide a condensed chronicle contribution offered by mollusks to studies how where nervous system encodes stores memory describe rich cognitive capabilities some insect species, including attention concept learning. also discuss planarians investigating dynamics during brain regeneration highlight role stressful stimuli in forming memories. Furthermore, focus increasing evidence that display forms emotions, which provides new opportunities unveiling neural molecular underlying complex interaction between stress, emotions cognition. doing so, experimental challenges suggest future directions expect field take coming years, particularly regarding what we, humans, need know preventing and/or delaying loss. This article has an associated ECR Spotlight interview with Veronica Rivi.

Language: Английский

---

Taste cells expressing Ionotropic Receptor 94e reciprocally impact feeding and egg laying in Drosophila

Cell Reports, Journal Year: 2024, Volume and Issue: 43(8), P. 114625 - 114625

Published: Aug. 1, 2024

Chemosensory cells across the body of Drosophila melanogaster evaluate environment to prioritize certain behaviors. Previous mapping gustatory receptor neurons (GRNs) on fly labellum identified a set in L-type sensilla that express Ionotropic Receptor 94e (IR94e), but impact IR94e GRNs behavior remains unclear. We used optogenetics and chemogenetics activate found they drive mild feeding suppression enhance egg laying. In vivo calcium imaging revealed respond strongly amino acids, including glutamate, plus co-receptors IR25a IR76b are required for acid detection. Furthermore, mutants show behavioral changes solutions containing increased consumption decreased Overall, our results suggest discourage encourage laying as part an important switch response chemical cues.

Language: Английский

---

Descending control of motor sequences in

Current Opinion in Neurobiology, Journal Year: 2023, Volume and Issue: 84, P. 102822 - 102822

Published: Dec. 13, 2023

The descending neurons connecting the fly's brain to its ventral nerve cord respond sensory stimuli and evoke motor programs of varying complexity. Anatomical characterization their synaptic connections suggests how these circuits organize movements, while optogenetic manipulation activity reveals what behaviors they can induce. Monitoring responses or during behavior performance indicates information may encode. Recent advances in all three approaches make an excellent place better understand sensorimotor integration transformation required for nervous systems govern sequences that constitute animal behavior.

Language: Английский

---

Switching neuron contributions to second network activity

Journal of Neurophysiology, Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 10, 2024

Network flexibility is important for adaptable behaviors. This includes neuronal switching, where neurons alter their network participation, including changing from single- to dual-network activity. Understanding the implications of switching requires determining how a neuron interacts with each its networks. Here, we tested 1) whether "home" and second networks, operating via divergent rhythm generation mechanisms, regulate neuron, 2) if recruited modulation intrinsic properties, contributes or pattern in new network. Small, well-characterized feeding-related networks (pyloric, ~1 Hz; gastric mill, ~0.1 Hz) identified modulatory inputs make isolated crab ( Cancer borealis) stomatogastric nervous system (STNS) useful model study switching. In particular, neuropeptide Gly 1 -SIFamide switches lateral posterior (LPG) (2 copies) pyloric-only dual-frequency pyloric/gastric mill (fast/slow) activity LPG properties. Using current injections manipulate activity, found that but not pyloric, regulated intrinsically generated slow bursting. Conversely, selective elimination both using photoinactivation revealed firing frequencies was necessary coordination. However, alone sufficient produce distinct Thus, modulated properties underlying participation may constrain which can Further, recruitment occur states it actively contribute output.

Language: Английский

---

Diverse prey capture strategies in teleost larvae

Published: Feb. 10, 2025

Animal behavior is adapted to the sensory environment in which it evolved, while also being constrained by physical limits, evolutionary history, and developmental trajectories. The hunting of larval zebrafish ( Danio rerio ), a cyprinid native streams Eastern India, has been well characterized. However, unknown if complement sequence movements employed during prey capture universal across freshwater teleosts. Here, we explore syntax fish belonging clade Percomorpha , whose last common ancestor with cyprinids lived ∼240 million years ago. We compared four cichlid species from Lake Tanganyika endemic deep benthic parts lake Lepidiolamprologus attenuatus Lamprologus ocellatus Neolamprologus multifasciatus ) or inhabiting rivers Astatotilapia burtoni that medaka Oryzias latipes found rice paddies East Asia. Using high speed videography neural networks, tracked eye extracted swim kinematics larvae these five species. Notably, repertoire cichlids broader than zebrafish, but shares basic features, such as convergence, positioning centrally binocular visual field, discrete bouts, including two kinds strikes. In contrast, continuously, track monocularly without position laterally before capturing them side swing. This configuration kinematic motifs suggests may judge distance predominantly motion parallax, mainly use cues. Together, our study documents diversification locomotor oculomotor adaptations among teleost larvae.

Language: Английский

---

Neural circuit regulation by identified modulatory projection neurons

Frontiers in Neuroscience, Journal Year: 2023, Volume and Issue: 17

Published: March 17, 2023

Rhythmic behaviors (e.g., walking, breathing, and chewing) are produced by central pattern generator (CPG) circuits. These circuits highly dynamic due to a multitude of input they receive from hormones, sensory neurons, modulatory projection neurons. Such inputs not only turn CPG on off, but adjust their synaptic cellular properties select behaviorally relevant outputs that last seconds hours. Similar the contributions fully identified connectomes establishing general principles circuit function flexibility, neurons have enabled key insights into neural modulation. For instance, while bath-applying neuromodulators continues be an important approach studying modulation, this does always mimic response neuronal release same modulator. There is additional complexity in actions neuronally-released modulators to: (1) prevalence co-transmitters, (2) local- long-distance feedback regulating timing (co-)release, (3) differential regulation co-transmitter release. Identifying physiological stimuli neurons) activate has demonstrated multiple "modulatory codes" for selecting particular outputs. In some cases, population coding occurs, others output determined firing rate The ability perform electrophysiological recordings manipulations small populations at levels rhythmic motor systems remains determining mechanisms underlying rapid adaptability

Language: Английский

---