About

Gilad Barnea, Ph.D., is a professor involved in research utilizing molecular genetic tools to study genes, circuits, and behavior. He is a member of the Barnea Lab, which focuses on understanding the genetic and neural mechanisms underlying behavior through advanced genetic and neurobiological techniques. His work contributes to elucidating the complex interactions between genes and neural circuits that influence behavior, although specific details of his research focus are not provided in the page text.

Research topics

• Biology
• Neuroscience
• Genetics
• Medicine
• Cell biology
• Psychology
• Botany

Selected publications

• Feeding decision-making by a single neuron via disparate neurotransmitters

  Nature Communications · 2026-02-13

  articleOpen accessSenior authorCorresponding

  Animals use gustatory information to decide whether to ingest nutritious substances or avoid toxic ones. Although certain neurons in the gustatory circuits respond to both aversive and appetitive signals, how these neurons resolve inputs with opposing valences is unknown. Here, we examine how the Drosophila melanogaster neuropeptide leucokinin (LK) affects gustatory information processing to elicit the appropriate feeding behaviors. We identify the subesophageal LK neurons (SELKs) as downstream synaptic partners of gustatory receptor neurons and show that these two groups are functionally connected. We then show that SELKs affect bitter avoidance through LK release and food intake in an acetylcholine-dependent manner. Our study uncovers a mechanism whereby strong activation of SELKs results in LK release, leading to feeding suppression, while weak activation results in acetylcholine-dependent feeding promotion. Thus, our results reveal that a single pair of neurons, SELKs, differentially controls opposing feeding behaviors via distinct neurotransmitters. How neurons resolve gustatory inputs with opposing valences is currently unknown. Here, authors show that bitter and sweet gustatory receptor neurons in fruit flies converge on a pair of neuropeptidergic neurons that instruct opposing feeding behaviors via distinct transmitters based on the input they receive

  PublisherDOI

• Author Correction: Transsynaptic labeling and transcriptional control of zebrafish neural circuits

  Nature Neuroscience · 2025-11-10

  erratumOpen access
  PublisherOA PDFDOI

• Hunger Recruits a Parallel Circuit Encoding Alcohol Reward

  bioRxiv (Cold Spring Harbor Laboratory) · 2025-10-15

  preprintOpen access

  Summary Internal states like hunger, pain, thirst and arousal can bias behavior by affecting sensory and memory processing. Internal states are critical to understand in the context of alcohol addiction because they influence cravings, reinstatement, and relapse. Norepinephrine plays a key role in both hunger and alcohol-induced arousal and preference, but the circuit-level mechanisms through which it modulates the influence of hunger on alcohol preference are not well understood. We sought to address this using intersectional genetic tools for manipulating neurons expressing octopamine, the invertebrate analogue of vertebrate norepinephrine. We identified a single octopamine neuron required for ethanol seeking only when Drosophila are food-deprived. Hunger increased baseline activity in this neuron, making it more responsive to an odor cue previously paired with ethanol. A combination of genetic and connectome analyses revealed that synaptic partners of this octopaminergic neuron form a functional module that acts on Drosophila memory circuitry. Thus, we show that hunger recruits a parallel circuit that drives learned ethanol preference, providing a neuronal framework through which internal state influences the expression of memory for ethanol-associated cues.

  PublisherOA PDFDOI

• Convergent olfactory circuits for courtship in <i>Drosophila</i> revealed by <i>ds</i> -Tango

  bioRxiv (Cold Spring Harbor Laboratory) · 2024-10-23

  preprintOpen accessSenior authorCorresponding

  Summary Animals exhibit sex-specific behaviors that are governed by sexually dimorphic circuits. One such behavior in male Drosophila melanogaster , courtship, is regulated by various sensory modalities, including olfaction. Here, we reveal how sexually dimorphic olfactory pathways in male flies converge at the third-order, onto lateral horn output neurons, to regulate courtship. To achieve this, we developed ds -Tango, a modified version of the monosynaptic tracing and manipulation tool trans- Tango. In ds -Tango, two distinct configurations of trans- Tango are positioned in series, thus providing selective genetic access not only to the monosynaptic partners of starter neurons but also to their disynaptic connections. Using ds -Tango, we identified a node of convergence for three sexually dimorphic olfactory pathways. Silencing this node results in deficits in sex recognition of potential partners. Our results identify lateral horn output neurons required for proper courtship behavior in male flies and establish ds -Tango as a tool for disynaptic circuit tracing.

  PublisherOA PDFDOI

• Continuous integration of heading and goal directions guides steering

  bioRxiv (Cold Spring Harbor Laboratory) · 2024-10-26

  preprintOpen accessSenior authorCorresponding

  Abstract Navigating animals must integrate a diverse array of sensory cues into a single locomotor decision. Insects perform intricate navigational feats using a brain region termed the central complex in which an animal’s heading direction is transformed through several layers of circuitry to elicit goal-directed locomotion. These transformations occur mostly in the fan-shaped body (FB), a major locus of multi-sensory integration in the central complex. Key aspects of these sensorimotor computations have been extensively characterized by functional studies, leveraging the genetic tools available in the fruit fly. However, our understanding of how neuronal activity in the FB dictates locomotor behaviors during navigation remains enigmatic. Here, we manipulate the activity of two key neuronal populations that input into the FB–the PFN a and PFN d neurons–used to encode the direction of two complex navigational cues: wind plumes and optic flow, respectively. We find that flies presented with unidirectional optic flow steer along curved walking trajectories, but silencing PFN d neurons abolishes this curvature. We next use optogenetic activation to introduce a fictive heading signal in the PFNs to establish the causal relationship between their activity and steering behavior. Our studies reveal that the central complex guides locomotion by summing the PFN-borne directional signals and shifting movement trajectories left or right accordingly. Based on these results, we propose a model of central complex-mediated locomotion wherein the fly achieves fine-grained control of sensory-guided steering by continuously integrating its heading and goal directions over time.

  PublisherOA PDFDOI

• Transsynaptic labeling and transcriptional control of zebrafish neural circuits

  Nature Neuroscience · 2024-12-19 · 10 citations

  article
  PublisherDOI

• Author response: retro-Tango enables versatile retrograde circuit tracing in Drosophila

  2023-03-29

  peer-reviewOpen accessSenior author
  PublisherDOI

• Transsynaptic labeling and transcriptional control of zebrafish neural circuits

  bioRxiv (Cold Spring Harbor Laboratory) · 2023-04-03 · 6 citations

  preprintOpen access

  Deciphering the connectome, the ensemble of synaptic connections that underlie brain function is a central goal of neuroscience research. The trans-Tango genetic approach, initially developed for anterograde transsynaptic tracing in Drosophila, can be used to map connections between presynaptic and postsynaptic partners and to drive gene expression in target neurons. Here, we describe the successful adaptation of trans-Tango to visualize neural connections in a living vertebrate nervous system, that of the zebrafish. Connections were validated between synaptic partners in the larval retina and brain. Results were corroborated by functional experiments in which optogenetic activation of retinal ganglion cells elicited responses in neurons of the optic tectum, as measured by trans-Tango-dependent expression of a genetically encoded calcium indicator. Transsynaptic signaling through trans-Tango reveals predicted as well as previously undescribed synaptic connections, providing a valuable in vivo tool to monitor and interrogate neural circuits over time.

  PublisherOA PDFDOI

• Opposing, spatially-determined epigenetic forces impose restrictions on stochastic olfactory receptor choice

  2023-05-12 · 3 citations

  preprintOpen access

  Abstract Olfactory receptor (OR) choice represents an example of genetically hardwired stochasticity, where every olfactory neuron expresses one out of ~2000 OR alleles in a probabilistic, yet stereotypic fashion. Here, we show that topographic restrictions in OR expression are established in neuronal progenitors by two opposing forces: polygenic transcription and genomic silencing, both of which are influenced by dorsoventral gradients of transcription factors NFIA, B, and X. Polygenic transcription defines spatially constrained OR repertoires, among which one OR allele may be selected for singular expression later in development. Heterochromatin assembly and genomic compartmentalization preferentially eliminate from this “privileged” repertoire ORs with more dorsal expression destinations, which are ectopically transcribed in neuronal progenitors throughout the olfactory epithelium. Our experiments identify early transcription as an “epigenetic” contributor to future developmental patterning and reveal how two spatially responsive probabilistic processes act in concert to establish deterministic, precise, and reproducible territories of stochastic gene expression.

  PublisherDOI

• Opposing, spatially-determined epigenetic forces impose restrictions on stochastic olfactory receptor choice

  2023-11-22 · 1 citations

  preprintOpen access

  Abstract Olfactory receptor (OR) choice represents an example of genetically hardwired stochasticity, where every olfactory neuron expresses one out of ∼2000 OR alleles in a probabilistic, yet stereotypic fashion. Here, we propose that topographic restrictions in OR expression are established in neuronal progenitors by two opposing forces: polygenic transcription and genomic silencing, both of which are influenced by dorsoventral gradients of transcription factors NFIA, B, and X. Polygenic transcription of OR genes may define spatially constrained OR repertoires, among which one OR allele is selected for singular expression later in development. Heterochromatin assembly and genomic compartmentalization of OR alleles also vary across the axes of the olfactory epithelium and may preferentially eliminate ectopically expressed ORs with more dorsal expression destinations from this “privileged” repertoire. Our experiments identify early transcription as a potential “epigenetic” contributor to future developmental patterning and reveal how two spatially responsive probabilistic processes may act in concert to establish deterministic, precise, and reproducible territories of stochastic gene expression.

  PublisherOA PDFDOI

Recent grants

• Functional mapping of mammalian neural circuits

  NIH · $1.3M · 2014–2018

• NIH Grant R01MH086920

  NIH · $1.5M · 2013

• NIH Grant R21DC014333

  NIH · $447k · 2017

• An olfactory subsystem that mediates innate behaviors

  NIH · $3.1M · 2014–2020

• The neural circuits underlying gustatory perception in flies

  NIH · $2.0M · 2018–2024

Frequent coauthors

• Mustafa Talay

  105 shared

• Altar Sorkaç

  61 shared

• Nathaniel J. Snell

  36 shared

• Stavros Lomvardas

  Columbia University

  35 shared

• Doruk Savaş

  34 shared

• Alexander Fleischmann

  Providence College

  30 shared

• Benjamin Shykind

  30 shared

• Nell Klimpert

  Allen Institute for Brain Science

  30 shared

Labs

• Barnea LabPI