Preprints
Non Peer-Reviewed Preprints
GOOGLE SCHOLAR - PUBMED - ORCiD
Only preprints without peer-reviewed manuscripts are shown.
2024
Distinct dynamics and intrinsic properties in ventral tegmental area populations mediate reward association and motivation
Jordan E Elum, Eric R Szelenyi, Barbara Juarez, Alexandria D Murry, Grigory Loginov, Catalina A Zamorano, Pan Gao, Ginny Wu, Scott Ng-Evans, Xiangmin Xu, Sam A Golden, Larry S Zweifel
bioRxiv 2024.02.05.578997; doi: https://doi.org/10.1101/2024.02.05.578997
Ventral tegmental area (VTA) dopamine neurons regulate reward-related associative learning and reward-driven motivated behaviors, but how these processes are coordinated by distinct VTA neuronal subpopulations remains unresolved. Here we examine the neural correlates of reward-related prediction-error, action, cue, and outcome encoding as well as effort exertion and reward anticipation during reward-seeking behaviors. We compare the contribution of two primarily dopaminergic and largely non-overlapping VTA subpopulations, all VTA dopamine neurons, and VTA GABAergic neurons of the mouse midbrain to these processes. The dopamine subpopulation that projects to the nucleus accumbens (NAc) core preferentially encodes prediction-error and reward-predictive cues. In contrast, the dopamine subpopulation that projects to the NAc shell preferentially encodes goal-directed actions and reflects relative reward anticipation. VTA GABA neuron activity strongly contrasts VTA dopamine population activity and preferentially encodes reward outcome and retrieval. Electrophysiology, targeted optogenetics, and whole-brain input mapping reveal heterogeneity among VTA dopamine subpopulations. Our results demonstrate that VTA subpopulations carry distinct reward-related learning and motivation signals and reveal a striking pattern of functional heterogeneity among projection-defined VTA dopamine neuron populations.
Opioid-driven disruption of the septal complex reveals a role for neurotensin-expressing neurons in withdrawal
Rhiana C. Simon, Weston T. Fleming, Pranav Senthilkumar, Brandy A. Briones, Kentaro K. Ishii, Madelyn M. Hjort, Madison M. Martin, Koichi Hashikawa, Andrea D. Sanders, Sam A. Golden, Garret D. Stuber
bioRxiv 2024.01.15.575766; doi: https://doi.org/10.1101/2024.01.15.575766
Because opioid withdrawal is an intensely aversive experience, persons with opioid use disorder (OUD) often relapse to avoid it. The lateral septum (LS) is a forebrain structure that is important in aversion processing, and previous studies have linked the lateral septum (LS) to substance use disorders. It is unclear, however, which precise LS cell types might contribute to the maladaptive state of withdrawal. To address this, we used single-nucleus RNA-sequencing to interrogate cell type specific gene expression changes induced by chronic morphine and withdrawal. We discovered that morphine globally disrupted the transcriptional profile of LS cell types, but Neurotensin-expressing neurons (Nts; LS-Nts neurons) were selectively activated by naloxone. Using two-photon calcium imaging and ex vivo electrophysiology, we next demonstrate that LS-Nts neurons receive enhanced glutamatergic drive in morphine-dependent mice and remain hyperactivated during opioid withdrawal. Finally, we showed that activating and silencing LS-Nts neurons during opioid withdrawal regulates pain coping behaviors and sociability. Together, these results suggest that LS-Nts neurons are a key neural substrate involved in opioid withdrawal and establish the LS as a crucial regulator of adaptive behaviors, specifically pertaining to OUD.
2023
An arginine-rich nuclear localization signal (ArgiNLS) strategy for streamlined image segmentation of single-cells
Eric R. Szelenyi, Jovana S. Navarrete, Alexandria D. Murry, Yizhe Zhang, Kasey S. Girven, Lauren Kuo, Marcella M. Cline, Mollie X. Bernstein, Mariia Burdyniuk, Bryce Bowler, Nastacia L. Goodwin, Barbara Juarez, Larry S. Zweifel, Sam A. Golden
bioRxiv 2023.11.22.568319; doi: https://doi.org/10.1101/2023.11.22.568319
High-throughput volumetric fluorescent microscopy pipelines can spatially integrate whole-brain structure and function at the foundational level of single-cells. However, conventional fluorescent protein (FP) modifications used to discriminate single-cells possess limited efficacy or are detrimental to cellular health. Here, we introduce a synthetic and non-deleterious nuclear localization signal (NLS) tag strategy, called 'Arginine-rich NLS' (ArgiNLS), that optimizes genetic labeling and downstream image segmentation of single-cells by restricting FP localization near-exclusively in the nucleus through a poly-arginine mechanism. A single N-terminal ArgiNLS tag provides modular nuclear restriction consistently across spectrally separate FP variants. ArgiNLS performance in vivo displays functional conservation across major cortical cell classes, and in response to both local and systemic brain wide AAV administration. Crucially, the high signal-to-noise ratio afforded by ArgiNLS enhances ML-automated segmentation of single-cells due to rapid classifier training and enrichment of labeled cell detection within 2D brain sections or 3D volumetric whole-brain image datasets, derived from both staining-amplified and native signal. This genetic strategy provides a simple and flexible basis for precise image segmentation of genetically labeled single-cells at scale and paired with behavioral procedures.
A diverse network of pericoerulear neurons control arousal states
Andrew T. Luskin, Li Li, Xiaonan Fu, Kelsey Barcomb, Taylor Blackburn, Madison Martin, Esther M. Li, Akshay Rana, Rhiana C. Simon, Li Sun, Alexandria D. Murry, Sam A. Golden, Garret D. Stuber, Christopher P. Ford, Liangcai Gu, Michael R. Bruchas
bioRxiv 2022.06.30.498327; doi: https://doi.org/10.1101/2022.06.30.498327
As the primary source of norepinephrine (NE) in the brain, the locus coeruleus (LC) regulates both arousal and stress responses. However, how local neuromodulatory inputs contribute to LC function remains unresolved. Here we identify a network of transcriptionally and functionally diverse GABAergic neurons in the LC dendritic field that integrate distant inputs and modulate modes of LC firing to control arousal. We define peri-LC anatomy using viral tracing and combine single-cell RNA sequencing and spatial transcriptomics to molecularly define both LC and peri-LC cell types. We identify several cell types which underlie peri-LC functional diversity using a series of complementary approaches in behaving mice. Our findings indicate that LC and peri-LC neurons comprise transcriptionally and functionally heterogenous neuronal populations, alongside anatomically segregated features which coordinate specific influences on behavioral arousal and avoidance states. Defining the molecular, cellular and functional diversity in the LC provides a road map for understanding the neurobiological basis of arousal alongside hyperarousal-related neuropsychiatric phenotypes.