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Ren, J.

Publications and source records attributed to Ren, J..

At least 37 records · Page 2Linked to original sources

Gliomas preferentially develop within the action-mode network

Gliomas tend to arise in specific brain regions and may integrate into functional circuits, suggesting they could be regulated by brain activity. However, it remains unclear whether glioma growth is related to system-level brain networks. Analyzing neuroimaging data from three datasets including 1,310 patients with cerebral gliomas, we identified and replicated a functionally connected glioma network, which overlaps with the action-mode network (AMN), somatomotor network (SMN), and action-related subcortical regions. Resting-state functional connectivity (RSFC) of the AMN successfully predicted the location of glioma occurrence in two independent datasets with complex tumor distributions. Remarkably, no patient had a glioma entirely outside the AMN, and over 89% of patients exhibited gliomas with at least 50% overlap with the network. Moreover, the spatial overlap between glioma location and the AMN demonstrated significant prognostic value in survival analyses, with higher AMN-tumor overlap associated with poorer overall survival. Notably, the acetylcholine transporter, a key player in glioma pathogenesis that drives transcriptional reprogramming, showed an expression pattern overlapping with the AMN. Meta-analytic annotations further linked the glioma network to processes of action initiation, execution, and feedback. These findings indicate that gliomas preferentially arise in circuits involved in action and highlight the central role of the AMN in glioma pathophysiology and growth.

neuroscience↗

A Combinatorial mRNA Therapy for Treating Rheumatoid Arthritis and Osteoarthritis by Inhibiting Inflammation and Promoting Cartilage Regeneration

Rheumatoid arthritis (RA) and osteoarthritis (OA) are debilitating joint disorders with distinct etiologies but share common pathological features of chronic inflammation and progressive cartilage damage. Current therapeutic options are largely palliative and yet fail to achieve desired effect. In this study, we developed a combinatorial mRNA therapy using a rationally engineered lipid nanoparticle (LNP) containing a novel ionizable lipid for enhanced cartilage penetration upon intra-articular administration. This LNP co-delivers mRNAs encoding two complementary therapeutic proteins: interleukin-1 receptor antagonist (IL-1Ra) for inflammation attenuation and a C-terminal truncated derivative of angiopoietin-like 3 (ANL3) for cartilage regeneration. In pre-clinical models including collagen-induced arthritis mice, TNF-transgenic mice with spontaneous RA and destabilization of medial meniscus (DMM) surgical OA model, this "one-shot" combinatorial therapy significantly ameliorated disease severity, reduced synovitis and bone erosion, and potently promoted the regeneration of hyaline-like cartilage. Mechanistically, transcriptomic profiling of joint specimens revealed that the combinatorial therapy concurrently suppressed inflammatory pathways and extracellular matrix degradation pathways, meanwhile upregulating anabolic genes facilitating chondrogenesis. Collectively, our study establishes a versatile and synergistic mRNA therapy that offers a potent disease-modifying immunomodulatory strategy capable of addressing the long-standing unmet needs in arthritis treatment.

immunology↗

Microbiome-behavior coupling shapes infant adaptation to early maternal unpredictability

We asked whether infant microbiome composition, together with infants behavioral responses to early maternal unpredictability, can offer novel mechanistic insights into behavioral phenotypic variation in human development. Maternal unpredictability was computed as the entropy rate of transitions among maternal sensory signals during naturalistic mother-infant interaction (n=256 dyads; 2-6 months). Infant visual orienting behavior (VOB) was indexed by infants simultaneous gaze shifts to and from the mother. Higher maternal unpredictability predicted more frequent VOB shifts, indicating a mature-for-age profile, and longitudinally forecast poorer inhibitory control at 19-28 months. A subgroup of infants with high maternal unpredictability and high VOB had inhibitory control outcomes closer to those of infants who experienced low maternal unpredictability, suggesting VOB strategy might buffer against the effects of high maternal unpredictability. In participants with metagenomic data (n=93), VOB was associated with taxonomic and functional gut microbial profiles along a Bifidobacterium breve to Bifidobacterium longum axis. Neuroactive gene-set enrichment analysis linked VOB to increase in tryptophan synthesis and glutamate synthesis genes. In contrast, maternal unpredictability showed depletions of GABA and tryptophan synthesis in the unique-effects model and, when VOB and the maternal unpredictability by VOB term were included, enrichment of acetate synthesis and quinolinic acid degradation. Notably, the maternal unpredictability by VOB interactions for tryptophan and glutamate were negative, indicating that the VOB-pathway coupling attenuates as unpredictability increases. Together, these findings support a framework in which maternal unpredictability is the environmental challenge, infant VOB expresses the behavioral strategy, and microbial metabolism modulates whether that strategy is biochemically feasible. TeaserInfant gut microbiome is linked to infant behavioral responses to maternal unpredictability, which in turn impacts how they learn to control their actions.

neuroscience↗

GCP-VQVAE: A Geometry-Complete Language for Protein 3D Structure

AO_SCPLOWBSTRACTC_SCPLOWConverting protein tertiary structure into discrete tokens via vector-quantized variational autoencoders (VQ-VAEs) creates a language of 3D geometry and provides a natural interface between sequence and structure models. While pose invariance is commonly enforced, retaining chirality and directional cues without sacrificing reconstruction accuracy remains challenging. In this paper, we introduce GCP-VQVAE, a geometry-complete tokenizer built around a strictly SE(3)-equivariant GCPNet encoder that preserves orientation and chirality of protein backbones. We vector-quantize rotation/translation-invariant readouts that retain chirality into a 4 096-token vocabulary, and a transformer decoder maps tokens back to backbone coordinates via a 6D rotation head trained with SE(3)-invariant objectives. Building on these properties, we train GCP-VQVAE on a corpus of 24 million monomer protein backbone structures gathered from the AlphaFold Protein Structure Database. On the CAMEO2024, CASP15, and CASP16 evaluation datasets, the model achieves backbone RMSDs of 0.4377 [A], 0.5293 [A], and 0.7567 [A], respectively, and achieves 100% codebook utilization on a held-out validation set, substantially outperforming prior VQ-VAE-based tokenizers and achieving state-of-the-art performance. Beyond these benchmarks, on a zero-shot set of 1 938 completely new experimental structures, GCP-VQVAE attains a backbone RMSD of 0.8193 [A] and a TM-score of 0.9673, demonstrating robust generalization to unseen proteins. Lastly, we show that the Large and Lite variants of GCP-VQVAE are substantially faster than the previous SOTA (AIDO), reaching up to [~] 408 x and [~] 530 x lower end-to-end latency, while remaining robust to structural noise. We make the GCP-VQVAE source code, zero-shot dataset, and its pretrained weights fully open for the research community: https://github.com/mahdip72/vq_encoder_decoder

bioinformatics↗

Redirection of SARS-CoV-2 to phagocytes by intranasal sACE2-Fc as a universal decoy confers complete prophylactic protection

The rapid evolution of SARS-CoV-2 and other respiratory RNA viruses limits the success of current vaccines and antibody-based therapies. Engineered decoy receptors based on soluble angiotensin-converting enzyme 2 (sACE2) offer promising alternatives. Clinical-grade recombinant sACE2 inhibits SARS-CoV-2 replication in vitro but shows limited clinical success. This study reports an optimized sACE2 mutant fused to human IgG1 Fc (B5-D3), which redirects virus-decoy complexes to lysosomal degradation in macrophages. Intranasal prophylactic delivery of B5-D3 confers complete protection in SARS-CoV-2-infected K18-hACE2 mice. Abrogation of Fc effector functions compromises antiviral protection, indicating that Fc-mediated uptake of virus-decoy complexes is critical. Transcriptomic analysis suggests that B5-D3 induces early immune activation in lungs of infected mice. Bio-distribution and flow cytometry reveal selective targeting of airway phagocytes. In vitro assays confirm lysosomal degradation of virus-decoy complexes by macrophages without productive infection. These findings reveal a distinct antiviral mechanism via phagocytic clearance, supporting refined regimens for decoy treatments against SARS-CoV-2 and potentially other respiratory viruses.

immunology↗

Clonal dynamics shaped by diverse drug-tolerant persister states in melanoma resistance

Most advanced melanomas initially respond to targeted therapy but eventually relapse. Rather than acquiring new mutations, resistance is driven by drug-tolerant persister cells that enter a reversible drug-refractory state. We developed MeRLin, a high-resolution lineage tracing platform integrating cellular barcoding, single-cell transcriptomics, RNA fluorescence in situ hybridization (FISH), and computational analyses to track clonal and transcriptional dynamics in patient-derived melanoma models during prolonged therapy. Clonal dynamics revealed that persister subpopulations first responded to treatment but persisted and expanded during minimal residual disease, ultimately leading to tumor recurrence. Pre-treatment melanoma populations diversified into four conserved persister states characterized by stress-like, lipid metabolism, PI3K signaling, and extracellular matrix remodeling programs associated with adaptive resistance. Spatial transcriptomics showed the organization of these adaptive programs and a complex signaling network of autocrine and paracrine interactions among persister subpopulations. Barcoded RNA-FISH enabled spatial mapping of clonal identity and gene expression, revealing in situ co-localization of a dominant resistant clone with SLC2A1 expression. MeRLin provides a robust framework for dissecting cancer heterogeneity and identifying vulnerabilities in persister populations.

cancer biology↗

Chondrolectin regulates the sublaminar localization and regenerative function of muscle satellite cells in mice

Skeletal muscle satellite cells (SCs) reside between the myofiber sarcolemma and basal lamina, where extracellular matrix (ECM) interactions are essential for their maintenance and regenerative function. Here, we identify chondrolectin (CHODL), a type I transmembrane protein with a C-type lectin domain, as a critical regulator of SC biology. Single-cell RNA-seq analysis reveals that Chodl is highly enriched in quiescent SCs but downregulated in proliferating myoblasts. Using conditional knockout models, we show that deletion of Chodl in embryonic myoblasts (ChodlMKO) or adult SCs (ChodlPKO) does not affect muscle development but markedly impairs regeneration in both young and aged mice. Chodl-deficient SCs exhibit reduced self-renewal, diminish proliferation, and impair differentiation, leading to defective myofiber repair. In silico network perturbation further predicts disruption of ECM-ligand interactions and Notch signaling, consistent with our observation that a significant fraction of SCs in ChodlPKOmice localize outside the basal lamina and undergo precocious activation. Together, these findings establish CHODL as a key determinant of SC niche localization and regenerative function, uncovering a previously unrecognized mechanism linking ECM interactions to muscle stem cell maintenance and repair.

developmental biology↗

Instruction-tuned extraction of virus-host interactions from integrated scientific evidence

MotivationViral infectious diseases continue to pose a major threat to global health. Understanding protein-protein interactions (PPIs) and RNA-protein interactions (RPIs) between viruses and hosts is essential for elucidating infection mechanisms. However, manual curation of these interactions from biomedical literature is inefficient, creating a pressing need for automated and scalable extraction methods. Large language models (LLMs), such as the generative pre-trained transformer (GPT) and bidirectional encoder representations from transformers (BERT), offer promising solutions. Yet, most existing datasets focus on abstracts, overlooking other information-rich sections. We aim to develop a data-efficient approach to extract virus-host interaction (VHI) entities from full-text biomedical articles, including Results, Methods and tables. To our knowledge, this is the first study to apply instruction tuning to full-text VHI extraction ResultsWe curated a dataset containing 3, 395 PPI and 674 RPI entities from the Results, Materials and Methods sections, along with 566 PPIs and 793 RPIs from tables. Under low-resource conditions (<500 training examples), our instruction-tuned ChatMed-VHI model achieves the best overall performance (F1: 89.7%, Precision: 95.3%), outperforming PubMedBERT (F1: 74.6%, Precision: 75.1%). When scaled to the full dataset (>4, 000 training examples), ChatMed-VHI maintained the highest overall performance, while PubMedBERT achieved slightly higher precision (92.3% vs. 91.3%). Notably, ChatMed-VHI improved F1 and recall by 2.79% but precision dropped by 4.20% with more training data, whereas PubMedBERT improved consistently across all metrics. These results demonstrate the effectiveness of instruction-tuned LLMs for full-text biomedical extraction tasks, and position ChatMed-VHI as a scalable, domain-adaptable solution for VHI mining.

bioinformatics↗

Hepatocyte FAM210A deficiency disrupts mitochondrial function and triggers juvenile steatosis with compensatory repair in adulthood

Mitochondrial dynamics are central to maintaining liver metabolic homeostasis, yet the mechanisms that safeguarding mitochondrial integrity during development and metabolic dysfunction remain poorly defined. Here, we identify Family with sequence similarity 210 member A (FAM210A) as a hepatocyte-enriched mitochondrial regulator essential for postnatal liver maturation. Hepatocyte-specific deletion of Fam210a (Fam210aHKO) in mice caused early growth restriction, reduced body and liver mass, and pronounced hepatic steatosis with glycogen depletion. These defects were accompanied by lower postprandial glucose levels in the fasted-refeeding state, impaired oxidative phosphorylation, reduced mtDNA content, and abnormal cristae architecture. Transcriptomic and proteomic profiling revealed broad suppression of fatty acid, sterol, and bile acid metabolism, with concomitant glutathione stress responses. Mechanistically, FAM210A deficiency disrupted the YME1L-OPA1 axis, driving excessive OPA1 cleavage and cristae destabilization. Strikingly, these juvenile defects were transient and resolved by adulthood, underpinned by enhanced hepatocyte proliferation and mitochondrial biogenesis, consistent with a compensatory stress-adaptive response via the activation of ISR signaling. Together, these findings uncover FAM210A as a developmental safeguard of mitochondrial remodeling in hepatocytes and indicate compensatory programs with therapeutic relevance for chronic liver disease.

physiology↗

Distinct contributions and sensorimotor encoding of PV and FoxP2 neurons in the external globus pallidus during perceptual decision-making

The external globus pallidus (GPe), a central nucleus of the basal ganglia (BG), comprises diverse cell types, including PV and FoxP2 neurons. While their roles in movement regulation and sensory processing have been studied, their contributions to perceptual decision-making remain unclear. Using a Go/No-Go visual task in mice, we found that optogenetic activation of either population impaired behavioral performance, whereas only inhibition of PV neurons, but not FoxP2 neurons, disrupted behavior. Electrophysiological recordings revealed that PV and FoxP2 neurons exhibited distinct encoding of visual stimuli, licking movement, and trial outcomes, with a larger fraction of PV neurons positively encoding the reward-predicting (Go) stimulus and the population overall preferring the rewarded over unrewarded outcome. FoxP2 neuron inhibition had minimal effects on spontaneous firing of neurons in the substantia nigra pars reticulata (SNr), a major BG output. By contrast, PV neuron inhibition altered both spontaneous and task-related activity of SNr neurons, reducing their preference for reward-predicting stimulus or unrewarded outcome in a subpopulation-specific manner. These findings indicate that PV and FoxP2 neurons in the GPe differentially influence sensorimotor processing and SNr activity, with PV neurons playing a key role in supporting accurate performance during perceptual decision-making.

neuroscience↗

The RNA-Binding Protein HuR Regulates Splicing Programs in Osteocytes

Post-transcriptional gene regulation is central to maintaining cellular homeostasis, among its mechanism alternative splicing (AS) fine-tunes cellular adaptation to stress. In this study we employed an approach combining RNA splicing analysis to define RNA binding protein (RBP) motif enrichment around alternatively spliced exons in primary osteocytes cultured in high glucose conditions (HG). We identified the RBP human antigen R (HuR) as a top candidate regulator of AS. Loss of HuR reshaped the transcriptome through widespread changes in gene expression and splicing, converging on two major pathways: stress response and translational control. Functional validation of splicing revealed that HuR depletion heightened oxidative stress sensitivity and compromised cell viability under HG by stabilizing and upregulating TXNIP, a thioredoxin inhibitor. HuR knockdown also impaired mitochondrial mass and function and disrupted key translational signals, despite preserving global protein output. These findings establish HuR as a central post-transcriptional regulator of osteocyte survival and metabolic adaptation under high glucose stress, with potential implications for hyperglycemic bone fragility.

molecular biology↗

Benchmarking RNA velocity methods across 17 independent studies

RNA velocity techniques offer great potential for unveiling trajectories of cell state transitions in different biological contexts. While diverse computational methods have been developed, there is no evidence-based guidelines for best-practice in RNA velocity inference. Here we conducted a benchmark study for 14 existing RNA velocity methods in 17 independent datasets. Many validations were done for the first time. We evaluated the performances of each method by measuring accuracy, stability, and usability. Our data showed no single method exhibited superior performance in all the assessments, and unexpected underperformance was observed in certain cases. Especially, the lack of uniformity in the inference results highlights the necessity to compare and control of multiple methods in a single analysis. Our study revealed current limitations and challenges in the RNA velocity methods and informed the best-practice for future studies.

bioinformatics↗

Coiled-coil-mediated phase separation of Spef1 for non-centrosomal microtubule organization and function

Central-pair microtubules (CP-MTs) are non-centrosomal MTs essential for planar beat pattern of cilia. The CP-MT formation requires the MT-associated protein Spef1, but the underlying molecular mechanism remains unclear. Here, we show that Spef1 undergoes liquid-liquid phase separation (LLPS) to facilitate non-centrosomal MT assembly by enriching tubulins. The LLPS of Spef1 is mediated by its C-terminal coiled-coil (CC) domain. Crystallography reveals that the Spef1-CC domain forms a parallel CC dimer with a unique charge distribution pattern on the surface. The dimerization capacity and charge distribution of Spef1-CC are both critical for controlling in-vitro LLPS. Disruption of the dimerization capacity abolishes ciliary functions of Spef1. In contrast, a charge-changing mutant with attenuated LLPS still supports the CP-MT formation but results in cilia with abnormal beat pattern. Thus, the CC-mediated LLPS of Spef1 provides a mechanistic explanation for its prominent role in controlling non-centrosomal CP-MT organization and function in the axoneme. Significance statementThe MT-associated protein Spef1 is a new essential player for the non-centrosomal CP-MT formation in motile cilia and flagella. This study reveals the unexpected LLPS feature of Spef1, leading to forming biomolecular condensates that enrich tubulins to facilitate non-centrosomal MT assembly. Spef1-CC contains a unique charge-distribution pattern, together with its dimerization capacity, contributing to multivalent interactions for initiating LLPS. The LLPS property of Spef1 is important for CP-MT formation and Spef1-mediated ciliary function. The formation of Spef1-LLPS condensates indicates that they work as MT nucleation centers and tubulin sources for the continuous growth of CP-MTs or repairing CP-MTs damaged during ciliary beating, and suggests that LLPS may be a common process for generating and organizing non-centrosomal CP-MTs in the axoneme.

cell biology↗

Hedgehog and Bmp signaling pathways play opposing roles during establishment of the cardiac inflow tract in zebrafish

Cardiac pacemaking activity is controlled by specialized cardiomyocytes in the cardiac inflow tract (IFT), but the processes that determine IFT dimensions remain poorly understood. Here, we show that Hedgehog (Hh) signaling limits the number of IFT cardiomyocytes in the embryonic zebrafish heart. Inhibiting Hh signaling, either genetically or pharmacologically, results in an expanded IFT population. In contrast, reducing Bmp signaling decreases the number of IFT cardiomyocytes, while increasing Bmp signaling leads to an excess of IFT cardiomyocytes. Temporal inhibition of each pathway reveals that Hh and Bmp signaling act before myocardial differentiation to regulate IFT size. Simultaneous reduction of both Hh and Bmp signaling yields a relatively normal number of IFT cardiomyocytes, suggesting that these pathways function antagonistically during IFT development. Additionally, epistasis analysis suggests that Bmp signaling acts upstream of Wnt signaling to promote IFT formation, whereas Hh signaling limits IFT size in a Wnt-independent manner. Our results support a model in which Hh signaling restricts the establishment of the IFT progenitor pool, while Bmp signaling drives IFT progenitor specification prior to Wnt-directed IFT differentiation. SUMMARY STATEMENTHedgehog signaling acts prior to myocardial differentiation to restrict the number of inflow tract cardiomyocytes, while Bmp signaling acts during a similar timeframe to promote inflow tract cardiomyocyte formation.

developmental biology↗

An atlas of cell type specific regulatory effects in cattle

Understanding the genetic and molecular architecture of complex traits and artificial selection is crucial for advancing sustainable precision breeding in cattle and other livestock. Yet, how genetic variation affects cellular gene expression remains elusive in cattle. Here, by integrating 8,866 bulk RNA-seq samples and 999,192 single cells of 81 cell types in 22 bovine tissues, we presented a comprehensive atlas of regulatory variants at the cell type resolution in cattle. By colocalizing with bulk-tissue expression quantitative trait loci (beQTL), we detected 57,043 novel cell-type stratified eQTL and cell-type/state interaction eQTL in 18,153 genes, which also exhibited a stronger tissue/cell-type specificity than beQTL. By examining genome-wide associations (GWAS) of 44 complex traits, these cell-resolved eQTL were colocalized with 505 (24%) additional GWAS loci compared to beQTL. Through integrating this resource with selection signatures between dairy and beef cattle, we provided tissue/cell-specific regulatory insights into cattle breeding. Overall, the current atlas of cell-type-specific regulatory variants will serve as an invaluable resource for cattle genomics and selective breeding.

genetics↗

β-Glucan Modulates Monocyte Plasticity and Differentiation Capacity to Mitigate DSS-Induced Colitis

Trained immunity involves the reprogramming of innate immune cells after an initial exposure, resulting in heightened inflammatory responses to subsequent stimuli and enhanced bactericidal capacity during infection. However, this proinflammatory state could also exacerbate chronic conditions like inflammatory bowel disease (IBD), which is characterized by persistent inflammation and microbial imbalance. It remains unclear how trained immunity influences IBD pathogenesis and whether it can be harnessed therapeutically. In our study, pretreatment with {beta}-glucan reprogrammed bone marrow hematopoietic progenitors and peripheral monocytes, inducing a profound shift in monocyte plasticity and significantly reducing the severity of dextran sulfate sodium (DSS)-induced colitis. Adoptive transfer of bone marrow or peripheral monocytes from {beta}-glucan-trained mice into naive mice conferred robust protection against colitis, demonstrating that this protective effect is transferable. Trained mice also displayed improved clearance of intestinal bacterial infections. Single-cell RNA sequencing revealed an expansion of reparative Cx3cr1 macrophages derived from Ly6Chi monocytes, correlating with accelerated colonic epithelial regeneration. Collectively, these findings reveal how {beta}-glucan-induced trained immunity modulates monocyte differentiation to ameliorate experimental colitis, highlighting the potential of harnessing trained immunity as a therapeutic strategy to recalibrate innate immune responses and restore gut homeostasis in IBD, shedding light for future clinical applications. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=189 SRC="FIGDIR/small/653036v2_ufig1.gif" ALT="Figure 1"> View larger version (56K): org.highwire.dtl.DTLVardef@1b969c2org.highwire.dtl.DTLVardef@1ce603dorg.highwire.dtl.DTLVardef@10582forg.highwire.dtl.DTLVardef@10d7de6_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

Function of the auditory cortex characterized by its intrinsic dynamic coactivation patterns estimated in individuals

Determining the functional organization of the auditory cortex (AC) has been difficult with conventional task-based approaches due to the broad responsiveness of auditory subregions to various acoustic properties. Moreover, most studies have investigated functional organization of AC with static methods, although brain has shown to be organized into dynamic networks. Here, we investigated dynamically varying coactivation patterns of the local networks in the auditory cortex (AC) determined from 7T fMRI data with a novel individualized network-based algorithm. An eight-pattern solution was selected for closer examination based on its high reproducibility of the occurrence rates (r=0.86) and the spatial topography (r=0.79) between sessions. Dynamic AC patterns successfully captured interindividual variability, as indicated by significantly higher variability between than within individuals for the AC pattern occurrence rates and spatial topographies. The coactivation patterns shared similarities between resting-state and auditory-task data, as indicated by the group-level similarity of 0.84 and individual-level similarity of 0.71 in the spatial topographies. Furthermore, the occurrence rates of AC patterns identified in the task data, using pattern templates derived from resting-state data, correlated with specific task contrast regressors. Our results indicate that the AC function can be characterized by a set of dynamically varying coactivation patterns that are consistently observed during resting state and auditory stimulation, and that get synchronized with auditory input. These findings enhance our understanding of the relationship between spontaneous and stimulus-driven activity in the AC and support the development of more time-efficient paradigms for studying its functional organization.

neuroscience↗

Dysregulated Gene Regulatory Networks in Substance Use Disorder and HIV Infection: Insights from Single-Cell Genomics

Opioid use disorders (OUD) exacerbate the complexity of neurocognitive impairments and neurodevelopmental disorders, with poorly understood molecular mechanisms at the gene regulatory level. This study utilized single-nuclei RNA sequencing (snRNA-seq) data from the SCORCH (Single-Cell Opioid Responses in the Context of HIV) program, examining brain samples from 95 donors, including individuals with and without a history of opioid abuse, to explore the gene regulatory networks within the ventral tegmental area (VTA). While traditional differential gene expression analysis identified some significantly altered genes, including downregulation of FOS (p = 1.105e-3) in astrocytes from opioid users, our network-based approach revealed more profound disruptions in regulatory relationships. Most notably, correlation network analysis identified substantial alteration in FOS-centered regulatory networks, including complete loss of the FOS-NR4A1 connection despite unchanged NR4A1 expression levels. These findings suggest opioid-induced selective alterations in intracellular gene regulation, potentially contributing to addiction pathology and offering new insights into the molecular underpinnings of opioid-related neurocognitive dysfunction. This work expands our understanding of the mechanisms through which substance use disorders and HIV may synergistically impact brain function through altered gene regulatory networks, potentially revealing novel targets for therapeutic intervention.

systems biology↗