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Boender, A. J.

Publications and source records attributed to Boender, A. J..

5 recordsLinked to original sources

Natural variation in the oxytocin receptor gene predicts social observation in female prairie voles

Genetic variation in the oxytocin receptor gene (Oxtr) has been linked to differences in brain OXTR expression and long-term social bonds, but whether it shapes the moment-to-moment dynamics of early social interactions is unclear. Here we examined how the intronic Oxtr single nucleotide polymorphism (SNP) NT213739 in female prairie voles (Microtus ochrogaster) shapes their dynamic social interactions with an opposite-sex conspecific. Leveraging a computational pipeline to analyze the movements of freely interacting voles, we found that C/C females, which expressed higher OXTR levels in the nucleus accumbens than T/T females, spent more time socially observing novel males from a distance, especially early in interactions. This genotype-phenotype relationship persisted in multiple contexts, including the social preference test. Thus, natural Oxtr variation biases social observation in females toward unfamiliar males before bonds form, consistent with models where accumbens OXTR enhances the salience of social cues. These findings show that SNPs can shape subtle behavioral dimensions in early social encounters, with important implications for the role of oxytocin in the study of social attachment.

neuroscience↗

Comparative gene editing reduces dopamine receptor levels across rodent species

Translational challenges in neuroscience originate from species-specific differences that limit the generalizability of experimental findings. Comparative approaches can help distinguish conserved from species-specific mechanisms, but their application has been limited by the lack of molecular tools beyond traditional model organisms, complicating direct comparisons of conserved and divergent mechanisms of neural function. This gap is particularly evident for the dopaminergic system, a key regulator of motivated behaviors across species and the principal pharmacological target for current psychotherapies. Building on our recent development of comparative gene editing, we here present an adeno-associated virus-mediated CRISPR/Cas9 strategy to reduce in vivo dopamine receptors D1 and D2 levels across the rodent phylogeny. Using this approach, we achieved specific reduction of receptor levels in three rodent species (house mouse, prairie vole, and Syrian hamster), which we demonstrate with radioactive ligand binding assays. This toolkit expands the reach of comparative gene editing approaches, enabling functional investigation of the dopaminergic system across rodent species. Thereby, it supports comparative neuroscience by facilitating the identification of conserved versus species-specific neural mechanisms with enhanced translational potential.

neuroscience↗

Natural variation in oxytocin receptor signaling causes widespread changes in brain transcription: a link to the natural killer gene complex

Oxytocin (OXT) is a highly conserved neuropeptide that modulates social cognition, and genetic variation in its receptor gene (Oxtr) is linked to divergent social phenotypes. However, the molecular mechanisms connecting Oxtr genotype to behavioral outcomes remain obscure. Here, we leverage naturally occurring Oxtr polymorphisms in the prairie vole that associate with striatal-specific OXTR density to investigate how OXTR signaling influences brain function. Specifically, we identify OXTR-dependent transcriptomic changes in the natural killer gene complex (NKC) - a genomic region classically associated with peripheral immune function. Centrally, OXTR-regulated NKC genes are positioned to influence microglia-neuron interactions. Consistent with a role for these genes in shaping neuronal connectivity, we show that genetic reduction of OXTR levels leads to increased dendritic spine density on striatal Oxtr-expressing neurons. In addition, we provide support for a similar relation between variation in OXTR mRNA levels and NKC transcription in humans. Together, our findings suggest a role for OXTR signaling in the shaping of neural circuits through transcriptional control of the NKC, outlining a mechanism via which variation in OXTR signaling may influence circuit connectivity to generate diversity in social behaviors.

neuroscience↗

Social experience alters oxytocinergic modulation in the nucleus accumbens of female prairie voles

Social relationships are dynamic and evolve with shared and personal experiences. Whether the functional role of social neuromodulators also evolves with experience to shape the trajectory of relationships is unknown. We utilized pair bonding in the socially monogamous prairie voles as an example of socio-sexual experience that dramatically alters behaviors displayed toward other individuals. We investigated oxytocin-dependent modulation of excitatory synaptic transmission in the nucleus accumbens as a function of pair bonding status. We found that an oxytocin receptor agonist decreases the amplitude of spontaneous Excitatory Postsynaptic Currents (EPSCs) in sexually naive virgin, but not pair-bonded, female voles, while it increases the amplitude of electrically evoked EPSCs in paired voles, but not in virgins. This oxytocin-dependent potentiation of synaptic transmission relies on the de novo coupling between oxytocin receptor signaling and endocannabinoid CB1 receptor signaling in pair bonded voles. Blocking CB1 receptors after pair bond formation increases the occurrence of a specific form of social rejection - defensive upright response - that is displayed towards the partner but not towards a novel individual. Altogether, our results demonstrate that oxytocins action in the nucleus accumbens is changed through social experience in a way that regulates the trajectory of social interactions as the relationship with the partner unfolds, potentially promoting the maintenance of a pair bond by inhibiting aggressive responses. These results provide a mechanism by which social experience and context shift oxytocinergic signaling to impact neural and behavioral responses to social cues.

neuroscience↗

Plasticity of the glutamate transporter EAAT2 on striatal astrocytes regulates flexibility inbehavior

Modulation of striatal circuits is necessary for behavioral flexibility and confers the ability to adapt to environmental changes. Striatal astrocytes contribute to circuit neuromodulation by controlling the activity of ambient neurotransmitters. In particular, extracellular glutamate levels are tightly controlled by the astrocytic glutamate transporter EAAT2, thereby influencing synaptic functioning and neural network activity. While disturbances in EAAT2 have been related to neurological dysfunctions, it remains unclear if environmental cues influence this proteins function to specifically shape action control. In this study, we investigate the relationship between experience-dependent plasticity of EAAT2 expression and action inflexibility that follows overtraining for an instrumental task. We find that task overtraining is associated with the upregulation of EAAT2 in the lateral part of the dorsal striatum (DLS). Interfering with EAAT2 upregulation by chemogenetic activation of astrocytic Gq signaling or by transient in vivo knockdown of EAAT2 in the DLS restores behavioral flexibility. Astrocytes are emerging as critical regulators of striatal functions, and by demonstrating that plasticity of EAAT2 expression in the DLS shapes behavior, this work provides novel mechanistic insights into how flexibility in action control is regulated.

neuroscience↗