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Ibanez-Tallon, I.

Publications and source records attributed to Ibanez-Tallon, I..

5 recordsLinked to original sources

Cholinergic interneurons in the nucleus accumbens regulate the initiation of natural reward approach

Despite their established role in motivated behavior, how nucleus accumbens (NAc) cholinergic interneurons (CINs) contribute to natural reward seeking remains unclear. Here, we report that NAc CINs are key modulators of the approach phase of reward pursuit. Using in vivo fiber photometry in Chat-ires-Cre mice, we show that NAc CINs are robustly activated during the approach towards several salient stimuli including food, a social target, and a familiar object. We also provide evidence that this activation is potentially driven by olfactory cues. Disrupting NAc CIN function via targeted expression of a membrane-tethered toxin results in a delayed approach towards both food and a social target, but no alterations in object investigation, general locomotion or anxiety-related measures. Together, these findings identify NAc CINs as regulators of the initiation of natural reward approach and suggest that they link sensory information with onset of motivated action.

neuroscience↗

GPCRs as Targets for Human Brain Modulation: A Multi-omic Atlas of Cell-Type Specific Expression

G Protein coupled receptors (GPCRs) are the largest class of clinically validated drug targets with nearly 35% of all approved therapeutic agents acting on these receptors. To further explore the potential of this class of receptors for the development of circuit-specific and mechanism-based therapeutic strategies for neurological disorders, we focused on GPCRs with no known endogenous ligand, orphan GPCRs (oGPCRs), because knowledge of their functions in the human brain remains rudimentary. Here, we utilized fluorescence activated nuclear sorting and sequencing (FANSseq) to generate deep molecular profiles of cell type specific nuclei isolated from post-mortem brains to generate an atlas of oGPCR expression across multiple regions of the human brain. We identified 22 oGPCRs that displayed selective cell-type enrichment both in RNA transcript expression and chromatin accessibility. We further validated each of these targets for cell-type specific expression in human brains and developed an open-source web atlas of all oGPCR expression in the human brain to serve as a neuro-resource for the broader scientific community. These studies reveal novel cell-type specific expression patterns of several oGPCRs, suggest potential endogenous roles for these receptors, and identify validated candidates for cell-type specific neuromodulation of the human brain. One Sentence SummaryThis study presents an atlas of orphan GPCR expression across the human brain for translational targeting.

neuroscience↗

Estrus-Tracking Cortical Neurons Integrate Social cues and Reproductive states to Adaptively Control Sexually Dimorphic Sociosexual Behaviors

Female sociosexual behaviors, essential for survival and reproduction, are adaptively modulated by ovarian hormones. However, the neural mechanisms integrating internal hormonal states with external social cues to guide these behaviors remain poorly understood. Here we identified primary estrous-sensitive Cacna1h-expressing medial prefrontal (mPFCCacna1h+) neurons that orchestrate adaptive sociosexual behaviors. Bidirectional manipulation of mPFCCacna1h+ neurons drives opposite-sex-directed behavioral shifts between estrus and diestrus females. In males, these neurons serve opposite functions compared to estrus females, mediating sexually dimorphic effects via anterior hypothalamic outputs. Miniscope imaging reveals mixed-representation of self-estrous states and social target sex in distinct mPFCCacna1h+ subpopulations, with biased-encoding of opposite-sex social cues in estrus females and males. Mechanistically, ovarian hormone-driven upregulation of Cacna1h-encoded T-type calcium channels underlies estrus-specific activity changes and sexual-dimorphic function of mPFCCacna1h+ neurons. These findings uncover a prefrontal circuit that integrates internal hormonal states and target-sex information to exert sexually bivalent top-down control over adaptive social behaviors.

neuroscience↗

Precise 3D Localization of Intracerebral Implants with a simple Brain Clearing Method

Determining the localization of intracerebral implants in rodent brain stands as a critical final step in most physiological and behaviroral studies, especially when targeting deep brain nuclei. Conventional histological approaches, reliant on manual estimation through sectioning and slice examination, are error-prone, potentially complicating data interpretation. Leveraging recent advances in tissue-clearing techniques and light-sheet fluorescence microscopy, we introduce a method enabling virtual brain slicing in any orientation, offering precise implant localization without the limitations of traditional tissue sectioning. To illustrate the methods utility, we present findings from the implantation of linear silicon probes into the midbrain interpeduncular nucleus (IPN) of anesthetized transgenic mice expressing chanelrhodopsin-2 and enhanced yellow fluorescent protein under the choline acetyltransferase (ChAT) promoter/enhancer regions (ChAT-Chr2-EYFP mice). Utilizing a fluorescent dye applied to the electrode surface, we visualized both the targeted area and the precise localization, enabling enhanced inter-subject comparisons. Three dimensional (3D) brain renderings, presented effortlessly in video format across various orientations, showcase the versatility of this approach.

neuroscience↗

The Habenular Receptor GPR151 Regulates Addiction Vulnerability Across Drug Classes

The habenula controls the addictive properties of nicotine but also densely expresses opioid and cannabinoid receptors. As such, identification of strategies to manipulate habenular activity may yield new approaches to treat substance use disorders. Here we show that GPR151, an orphan G protein-coupled receptor (GPCR) highly enriched in the habenula of humans and rodents plays a critical role in regulating habenular function and behavioral responses to addictive drugs. We show that GPR151 is expressed on axonal and presynaptic membranes and synaptic vesicles, and regulates synaptic fidelity and plasticity. We find that GPR151 associates with synaptic components controlling vesicle release and ion transport and couples to the G-alpha inhibitory protein Go1 to reduce cAMP levels. Stable cell lines expressing GPR151 confirm that it signals via Gi/o and are amenable to ligand screens. Gpr151 null mice show diminished behavioral responses to nicotine, and self-administer greater quantities of the drug, phenotypes rescued by viral re-expression of Gpr151 in the habenula. Gpr151 null mice are also insensitive to the behavioral actions of morphine and cannabinoids. These data identify GPR151 as a critical modulator of habenular function that controls addiction vulnerability across different drug classes.\n\nHighlightsO_LIHabenula neurons are enriched in nicotinic, opioid, cannabinoid and GPR151 receptors\nC_LIO_LIGPR151 modulates synaptic fidelity and release probability at habenular terminals.\nC_LIO_LIHabenular GPR151 plays a role in drug abuse and food intake/weight control\nC_LIO_LIGPR151 couples to the G-alpha inhibitory protein Go1 to reduce cAMP levels.\nC_LI\n\neTOC BlurbAntolin-Fontes at al. identify a G protein-coupled receptor, GPR151, which is highly enriched in human habenular neurons. These neurons are primarily enriched with nicotinic, opioid and cannabinoid receptors. We find that GPR151 modulates habenular synaptic vesicle release probability and behavioral responses to these drugs of abuse.

neuroscience↗