Biology subjects

Taylor, S.

Publications and source records attributed to Taylor, S..

At least 19 recordsLinked to original sources

bioRxiv2026

Modelling habitat suitability for multiple priority weed species to predict invasion hotspots for strategic management in complex landscapes

Established invasive alien plant species require ongoing, costly management to reduce harm to agricultural and environmental values. Heterogeneous landscapes are often under threat from multiple long-established invasive plants, whose simultaneous management presents strategic and tactical challenges. Systematic monitoring of weed populations enables more strategic management by providing more detailed insights into invasion threats than the more readily available presence-only data. We leveraged six years of weed density monitoring and high-resolution environmental data to model habitat suitability for four high-priority weeds across the Australian Capital Territory. We developed habitat suitability maps for African lovegrass, Chilean needle grass, serrated tussock grass and St Johns wort. Maps were then standardised and combined to derive potential multi-species invasion hotspots at different management thresholds and explore patterns of secondary invasion threat. While some species shared environmental drivers such as elevation, each responded to distinct combinations and interactions among environmental drivers. Overall, we found approximately 71% of land had suitability for multiple weeds at various densities, but only 11% is suitable for two or more species to reach high densities. Areas suitable for most weeds often had St Johns wort as the next most suitable invader. These findings could improve management efficiency and reduce intervention challenges by focussing integrated control across species in a small number of priority areas. These findings support spatially explicit, multi-species decision-support tools for surveillance, prioritisation and strategic landscape-scale control.

ecology↗

bioRxiv2026

Modulating proton sensing by the adenosine receptor A2

For years, it was believed that G-protein-coupled receptors (GPCRs) activated or modulated by changes in physiological pH were mechanistically regulated by pH-sensitive histidine residues on the receptors exterior. More recent studies have shown that traditional acid-sensing GPCRs (GPR4, GPR65, GPR68) contain buried acidic amino acids in their 7-transmembrane regions and can be activated by pH-dependent mechanisms. The focus of our research has been the adenosine A2A receptor (A2AR) and its ability to activate at low pH levels without having the typical acidic triad structure found in previously studied acid-sensing GPCRs. We used a combination of bioinformatics and a humanized yeast-based platform, DCyFIR, to identify potential structures involved in the proton-sensing mechanism of A2AR. We also validated some of our A2AR variant yeast phenotypes using mammalian cells. Our data suggest that certain mutations eliminate the pH sensitivity of the A2AR while preserving agonist-induced signaling. Additionally, we demonstrated that one of our mutations (N284D) eliminates pH sensing but increases agonist potency, thereby providing a structural explanation for how pH-sensing and sodium binding occur that differs from previously established models. Overall, these data indicate that G-protein-coupled receptors can sense pH in several ways and demonstrate the potential of a novel, pH-insensitive A2AR in acid-related contexts.

molecular biology↗

bioRxiv2026

Proton-gating of opioid receptors and isoform functionality

The three opioid receptors, mu (mu-OR), delta (delta-OR), and kappa (kappa-OR), are key G-protein-coupled receptors (GPCRs) involved in mediating pain relief. Yet, there has been a lack of understanding regarding how changes in the extracellular pH associated with inflammation affect their signal transduction pathways. This study demonstrates that all opioid receptors act as proton-gated coincidence detectors. A humanized yeast-based platform called DCyFIR, which isolates the pH environment outside the cell from potential confounding factors inside the cell, was employed to examine the activation of opioid receptors over a range of physiologically relevant to pathologically low pH environments. As such, the results show that agonist efficacy decreases with decreasing pH. This indicates that the receptor itself contains one or more protonatable sidechains that act as an intrinsic "pH sensor". To determine the structural basis of this pH-sensing mechanism, structure-based pHinder calculations were used to identify potential pH sensing residues. Subsequent variant profiling identified the protonation of one conserved aspartic acid residue, D149 (also known as D3.32), located in a region near the binding site of opioid ligands, which, when exposed to acidic pH conditions, resulted in the disruption of the salt bridge necessary for effective docking of opioid ligands with the receptor. Consequently, the receptor lost all ability to be activated by agonists. Further characterization using a variety of functional assays on more than twenty different mu-OR alternative splicing variants indicated that all isoforms that possessed a continuous 7-transmembrane domain retained this proton-sensing capability. These studies collectively provide insight into the structural mechanisms underlying pH-dependent opioid receptor activation and lay the foundation for the design of new generations of selective analgesics that activate opioid receptors only in acidic inflammatory tissue.

molecular biology↗

bioRxiv2026

Next-generation genetically encoded biosensors for spatiotemporal intracellular pH monitoring, mapping, and profiling

Bioluminescence resonance energy transfer (BRET) systems are widely used for live-cell spectroscopy and biosensor engineering, yet the intrinsic pH sensitivity of commonly used BRET components has not been systematically examined. Here, we show that major BRET luciferase donors, fluorescent acceptors, and donor-acceptor assay pairs exhibit pronounced pH-dependent spectroscopic behavior across physiologically relevant conditions, identifying environmental pH responsiveness as a fundamental property of widely used BRET systems and a potential source of previously underappreciated assay artifacts. Leveraging these principles, we engineered ORION (ratiOmetRIc prOton seNsor), a genetically encoded ratiometric BRET pH sensor based on the NanoLuc-mVenus fusion. ORION exhibited strong brightness, an approximately 9-fold dynamic range, and robust responsiveness across a substantially broader pH range than that of existing genetically encoded sensors. Compared to pHluorin2, ORION maintained substantially improved quantitative performance at acidic pH values below 6.0. To demonstrate its utility in a biological application, we applied ORION across diverse cancer cell models and identified heterogeneous acid imprinting states, suggesting that tumor cells can retain persistent physiological memory of adaptation to acidic microenvironments even after prolonged ex vivo culture. Together, these findings establish pH responsiveness as a fundamental property of BRET systems and position ORION as a best-in-class platform for interrogating and quantifying pH regulation of biology in living systems.

biochemistry↗

bioRxiv2026

Systematic mapping of chimera-permissive sites by CRISPR-guided PAM scanning

Engineered protein chimeras enable new biological functions but remain difficult to design due to context-dependent constraints on insertion tolerance and the need to preserve host protein function. Here, we report CRISPR-guided protospacer adjacent motif (PAM) scanning in yeast to map chimera-permissive sites in living cells. We apply this approach to peptide and reporter insertions. In the first application, we generated 91 insertion chimeras encoding a defined protease cleavage sequence across six components of a model G protein-coupled receptor (GPCR) signaling pathway. Sixty-three percent of sites retain signaling, identifying positions that preserve host function and reveal broad, position-dependent tolerance. Coupling insertional scanning with cognate proteases enables site-resolved mapping of in-cell accessibility, distinguishing protected and exposed regions and defining EX1- and EX2-like regimes. These chimeras are responsive to proteolysis and pharmacological inhibition, enabling reversible control of protein activity. In a second application, we scanned 32 positions in yeast Ste2 and human A2A and MTNR1A receptors to engineer bi-functional chimeras that retain native function while incorporating reporter activity. Together, these results establish PAM scanning as a scalable, protein-agnostic framework for mapping insertion tolerance, interrogating protein accessibility in vivo, and enabling scalable ground-truth benchmarking of predictive chimera engineering.

synthetic biology↗

bioRxiv2026

SoftHybrid: A Hybrid Imputation Algorithm Optimised for Single-Cell Proteomics Data

Missing values (MVs) remain a significant barrier to reliable proteomics analysis, particularly in single-cell proteomics, where small amounts of starting material and limits in detection drive Missing-Not-At-Random (MNAR) sparsity. Existing imputation methods typically target either Missing-At-Random (MAR) or MNAR mechanisms, resulting in a trade-off between replicate consistency and preservation of biological variation, and are largely designed for bulk data. Here, we introduce SoftHybrid, a data-driven imputation framework that jointly models missingness and protein abundance to estimate the probability of MNAR, enabling continuous weighting between MAR- and MNAR-oriented strategies. SoftHybrid requires no external priors (cell type labels, group annotations, predefined missingness assumptions, etc.), enabling fully unsupervised applications. Across ground truth benchmarks and real single-cell proteomics datasets, SoftHybrid outperforms existing methods at low input and matches or exceeds their performance at the mini-bulk level. By preserving proteomic structure and abundance accuracy, it enhances the recovery of biologically meaningful signals. SoftHybrid is implemented as an R package and is freely available on GitHub.

bioinformatics↗

bioRxiv2025

Guam amyotrophic lateral sclerosis/parkinsonism-dementia complex (ALS/PDC) features CTE-like tau seeds in brain and spinal cord

Amyotrophic lateral sclerosis/parkinsonism-dementia complex (ALS/PDC) is a fatal neurodegenerative disorder that was once hyperendemic in the island of Guam (Mariana Islands, US) and a few other Pacific locales. Despite extensive investigations into its origins, the etiology of ALS/PDC remains unclear. ALS/PDC is, at the neuropathology level, characterized by tau-dominant multiple proteinopathy in brain and spinal cord. It was recently reported that Guam ALS/PDC brain extracts exhibit tau seeding activity in fluorescence resonance energy transfer (FRET)-based biosensor cells. To build upon those findings and explore the nature of tau seeds in ALS/PDC in more detail, we used an alanine mutational scanning (Ala scan) approach to determine the seeding profile of tau in nervous tissues of Guam ALS/PDC cases. First, we confirmed the detection of tau seeding activity in ALS/PDC brain samples in tau biosensor cells. Notably, we could also detect potent tau seeding activity in spinal cord. Subsequent Ala scan assays demonstrated that ALS/PDC tau displays an aggregate incorporation pattern that resembles that of chronic traumatic encephalopathy (CTE)-type tau. This result is consistent with recent electron cryo-microscopy studies of tau, which revealed that ALS/PDC tau filaments are predominantly of the CTE-type. The structural characteristics and seeding behavior of ALS/PDC tau, as well as the regional distribution of tau pathology at post-mortem, suggest that ALS/PDC is a CTE-like tauopathy. Significance StatementNeurodegenerative tauopathies are characterized by proteinaceous deposits containing microtubule-associated tau in nervous tissue. Emerging evidence suggests that disease-associated tau proteins adopt abnormal, self-propagating conformations characteristic of prions. Here, we employed alanine mutational scanning (Ala scan) to determine the nature of prion-like tau seeds in ALS/PDC, a mysterious disorder that occurred formerly in high incidence in certain regions in the western Pacific. We show that the Ala scan incorporation profile of ALS/PDC tau is similar to that of abnormal tau proteins in chronic traumatic encephalopathy (CTE). The findings lend support to the idea that ALS/PDC can be classified structurally as a CTE-like tauopathy. This work may have important implications for our understanding of ALS/PDC as well as common neurological disorders beyond the Pacific.

neuroscience↗

bioRxiv2025

Intrinsic and non-cell autonomous roles for a neurodevelopmental syndrome-linked transcription factor

Transcription factors (TFs) are essential for neuronal identity, yet their potential non-cell-autonomous functions remain largely unexplored. Here, we uncover both cell- and non-cell-autonomous roles for the conserved terminal selector UNC-3 in C. elegans motor neurons (MNs). UNC-3 is an ortholog of human EBF3, mutations in which cause a severe neurodevelopmental syndrome. Single-cell RNA sequencing of cholinergic MNs, which express unc-3, and downstream GABA MNs, which do not, revealed that unc-3 loss disrupts neuronal identity in distinct ways across MN classes. Four cholinergic MN classes lose their molecular identity entirely, whereas the AS class retains it partially, illuminating terminal selector-driven neuronal diversification processes. Integrated transcriptomic and genomic analyses uncovered a dual cell-autonomous role for UNC-3 as both a direct activator and repressor of neuron-type- specific genes in cholinergic MNs, including repression of alternate neurotransmitter programs. Unexpectedly, unc-3 loss also caused widespread transcriptional, morphological, and connectivity defects in downstream GABA MNs. Mechanistically, these non-cell-autonomous effects are mediated by cholinergic neurotransmission and include activation of the pro-regenerative bZIP TF CEBP-1 (C/EBP) and dysregulation of UNC-6/Netrin signaling. These findings redefine terminal selectors as both intrinsic and extrinsic regulators of neuronal identity and circuit assembly, offering a mechanistic framework for understanding EBF3 syndrome pathogenesis.

developmental biology↗

bioRxiv2025

Bladder mucosal afferents detect UTI and aid pathogen clearance

The bladder is innervated by a complex network of sensory neurons that detect and transmit mechanical and chemical signals to the central nervous system, regulating both urine storage and voiding, as well as mediating sensations of bladder fullness and pain. While stretch-sensitive afferents within the bladder wall are known to monitor filling, the contribution of stretch-insensitive afferents that reside within the bladder mucosa to bladder sensation and function remains unclear. Here, we establish a novel mouse model of selective bladder mucosal afferent denervation using intravesical instillation of resiniferatoxin (RTX) to define the functional roles of these fibres in health and disease. We assessed the impact of mucosal denervation on sensory nerve activity and bladder function in healthy mice and in a model of urinary tract infection (UTI) induced by acute bacterial challenge with uropathogenic E. coli. We show that mucosa-innervating afferents do not influence bladder distension responses or voiding function under healthy conditions. In contrast, during UTI, these afferents become hypersensitive and serve as critical drivers of infection-induced pelvic pain and urinary frequency, responses that contribute to enhanced bacterial clearance. Together, these findings identify bladder mucosal afferents as key sensors of pathogenic challenge and reveal a previously unrecognised mechanism that drives behavioural responses to reduce the burden and extent of UTI.

neuroscience↗

bioRxiv2025

ADAR1p150 RNA binding, independent of A-to-I RNA editing, buffers immunogenicity from the tonic type I IFN induced transcriptome in vivo.

ADAR1 edits adenosine to inosine (A-to-I) in double-stranded RNA to prevent MDA5 sensing of cellular transcripts, its key physiological role. However, editing-independent functions of ADAR1 remain poorly understood. Using a series of Adar1 mutant mice rescued by loss of MDA5 and PKR, we investigated isoform-specific, editing-independent roles of ADAR1 in vivo. We found that the cytoplasmic ADAR1p150 isoform is essential for maintaining peripheral T cell numbers and differentiation of hematopoietic stem and progenitor cells (HSPCs). In bone marrow transplants, ADAR1p150 protein, but not its editing activity, was crucial for T cell regeneration and HSPC repopulation, demonstrating a cell-intrinsic function in hematopoiesis. Experiments with IFN{beta}-treatment of purified HSPCs in vitro and in vivo IFNAR1 neutralization revealed hypersensitivity to tonic type I interferon (IFN) in the absence of ADAR1p150. Using cell lines, we demonstrate that type I IFN activates the OAS-RNaseL pathway, leading to cell death. This study shows that tonic type I IFN induces immunogenic cellular RNAs in sterile conditions. ADAR1p150 suppresses immune sensing of self-dsRNAs through both editing-dependent (MDA5) and editing-independent (PKR, OAS-RNaseL) mechanisms. Thus, ADAR1p150 protein levels and activity combine to set the threshold for tolerance to self-derived dsRNAs.

immunology↗

bioRxiv2025

Capture, Confine, Characterize: High-Throughput Dielectrophoresis-Based Single-Cell Microfluidics Platform to Analyze Mammalian and Yeast Cells Using Raman Spectroscopy

Single-cell analysis technologies are pivotal in unraveling complex biological mechanisms, yet existing platforms are often limited to sequencing-based end-point measurements, which fail to capture live cell dynamics. Here, we present a microfluidic- microelectronic device, the Microfluidic dielectrophoretic Arresting System (MiDAS) that employs dielectrophoresis (DEP) for high-throughput single-cell and droplet trapping in a compact array. We tested multiple trap geometries, including a 20 m-diameter DEP trap for polymer microbeads, fungal and mammalian cells, and a 40 m-diameter trap for water-in-oil droplets. The platform demonstrates broad sample compatibility, reliably immobilizing cells and beads of varying sizes. By integrating optical imaging and Raman spectroscopy, we enable rapid, non-destructive interrogation of individual cells with temporal resolution. We describe different modes of MiDAS operation to trap and manipulate single-cells or reverse emulsion droplets on demand, with applications in droplet microfluidics. Our MiDAS platforms simple fabrication, robust performance, and broad compatibility with diverse sample types position it as a versatile tool with transformative potential for single-cell analysis, offering researchers an innovative approach to interrogate cellular dynamics with unprecedented precision and throughput.

bioengineering↗

bioRxiv2025

WSB-1 regulates DNA repair and the response to DNA damage response inhibitors in breast cancer

Tumour hypoxia is a poor prognostic factor and linked with metastatic spread and treatment resistance in most solid tumours, including breast cancer. We previously showed hypoxia-regulated E3 ligase WSB-1s association with poor prognosis in breast cancer. Here, we evaluated the role of WSB-1 in DNA repair regulation in breast cancer, and whether these phenotypes can be exploited therapeutically. WSB-1 knockdown led to transcriptome-wide DNA repair factor upregulation, including homologous recombination (HR) factors BRCA1and RAD51. Reciprocally, WSB-1 overexpression led to downregulation of these repair factors and decreased DNA repair capacity. Patient gene expression datasets analyses also showed an inverse correlation between WSB1 expression vs DNA repair and HR pathways. HR-deficient cancers, including BRCA1/2-deficient breast cancers, are extremely sensitive to PARP inhibitors, a phenotype described as BRCAness. We therefore hypothesised if high WSB-1 expression could be similarly exploited therapeutically. WSB-1 overexpression alone radiosensitised cells and led to increased Olaparib (PARP inhibitor) and Berzosertib (ATR inhibitor) sensitivity in vitro. Our study indicates that WSB-1 expression in breast cancer is associated with modulation of HR factor expression, and we propose that elevated WSB-1 expression could be considered as a potential BRCAness biomarker and promote increased sensitivity to DNA repair targeted therapy in these patients.

cancer biology↗

bioRxiv2025

ChatMDV: Democratising Bioinformatics Analysis Using Large Language Models

BackgroundThe rapid advancement in single-cell, spatial omics, imaging, and genomic technologies requires robust analytical and visualisation platforms capable of managing complex biological data. Tools such as Multi-Dimensional Viewer (MDV) offer comprehensive interfaces for data exploration, but still require manual configuration and computational expertise to generate visualisation outputs, limiting accessibility for many users. ResultsWe present ChatMDV, a natural language interface integrated with MDV that allows users to generate high-quality interactive visualisations through natural language commands. ChatMDV employs a retrieval-augmented generation (RAG) pipeline combined with large language models (LLMs) to translate user queries into reproducible Python code and interactive output. This approach enables exploratory and targeted analysis in diverse biological domains. We demonstrate ChatMDVs capabilities using three datasets of increasing complexity: the Peripheral Blood Mononuclear Cells 3K (PBMC3K) dataset, the lung cancer atlas dataset hosted at the Human Cell Atlas and the longitudinal TAURUS study single-cell RNA-sequencing (scRNA-seq) dataset. ConclusionsBy bridging the gap between natural language processing and bioinformatics visualisation, ChatMDV reduces technical barriers, enhances reproducibility, and supports more inclusive scientific inquiry. Its modular design and adherence to FAIR (Findability, Accessibility, Interoperability, and Reuse) principles make it a scalable and adaptable framework for accelerating biological data analysis. Key PointsO_LIChatMDV enables users to create interactive visualisations from biological datasets using natural language. C_LIO_LIThe system combines large language models with MDVs graphical platform to simplify data exploration. C_LIO_LIIt supports reproducibility, adaptability, and FAIR data practices, making it suitable for a wide range of users and use cases. C_LI

bioinformatics↗

bioRxiv2025

Sealable capped nanovials for high-throughput screening of cell growth and function

Millions of modular nanoliter-scale compartments that isolate functionally rich single-cell and cell-to-cell communication data can scale biological discovery for the age of AI. Here, we introduce capped nanovials--suspendable, sealable microscale compartments formed by the docking of hydrogel capping particles into bowl-shaped nanovials--as a versatile system for culturing, analyzing, and sorting single cells and small colonies. This two-particle architecture enables localized confinement of cells and secreted products while maintaining compatibility with standard laboratory workflows such as wash and reagent exchange steps, fluorescence microscopy, and flow cytometry. Crucially, these compartments are formed via simple pipetting and centrifugation steps, making the platform highly democratized. We demonstrate the ability of capped nanovials to compartmentalize single mammalian, bacterial, and yeast cells and support growth into colonies, enabling selection based on proliferation and bioproduction. We further show that capped nanovials enhance single-cell secretion assays by reducing molecular crosstalk and increasing signal-to-noise ratios. Importantly, we demonstrate functional co-culture assays by permitting stable confinement of cell pairs, enabling detection and enrichment of antibody-secreting cells based on the ability of their secreted antibodies to activate co-encapsulated reporter T cells, achieving a signal-to-noise ratio of >30 and up to 100% selection purity. By combining the simplicity of standard lab handling with the resolution and throughput of traditional microfluidic compartmentalization approaches, capped nanovials provide a new class of scalable, accessible test tubes for modern single-cell biology.

bioengineering↗

bioRxiv2025

TARP γ-8 is a target of ethanol that regulates self-administration and relapse in mice

BackgroundBehavioral pathologies that characterize alcohol use disorder (AUD) are driven by the powerful reinforcing, or rewarding, properties of the drug. We have shown that glutamate AMPA receptor (AMPAR) activity is both necessary and sufficient for alcohol (ethanol) reinforcement. Transmembrane AMPAR regulatory protein (TARP) {gamma}-8 is an essential auxiliary protein that regulates AMPAR expression and activity; however, the role of TARP {gamma}-8 in AUD or other forms of addiction remains largely unexplored. ObjectivesThis study investigated the mechanistic role of TARP {gamma}-8 in operant ethanol self-administration (model of primary reinforcement) and cue-induced reinstatement of ethanol-seeking behavior (model of conditioned reinforcement) using TARP {gamma}-8 heterozygous null (+/-) mice. To determine if TARP {gamma}-8 signaling is targeted by ethanol use, we evaluated protein expression of TARP {gamma}-8, GluA1, CaMKII, and PSD-95 following ethanol self-administration. ResultsA battery of tests evaluating food and water intake, taste reactivity, anxiety-like behavior, and object recognition memory showed no fundamental behavioral deficits in TARP {gamma}-8 (+/-) mice, and no differences in response to acute ethanol or home-cage drinking as compared to wild-types. However, TARP {gamma}-8 (+/-) mice exhibited significantly reduced acquisition and escalation of operant ethanol self-administration and reduced cue-induced reinstatement of ethanol-seeking behavior, with no differences in parallel sucrose-only controls. In wild-type mice, ethanol self-administration increased TARP {gamma}-8 expression in the amygdala, nucleus accumbens, and hippocampus, and increased GluA1 expression in the amygdala and prefrontal cortex, compared to sucrose controls. ConclusionThese findings highlight the specificity of TARP {gamma}-8 regulation of ethanol reinforcement mechanisms and identify this crucial AMPAR auxiliary protein as a target of ethanol in reward-related brain regions, highlighting its potential for development of novel pharmacotherapies for AUD.

neuroscience↗

bioRxiv2025

Combined genomic and molecular analysis defines prognostic markers of relapse in stage IA-IC1 clear cell ovarian carcinoma

ObjectiveClear cell ovarian carcinoma (CCOC) is generally associated with a favourable prognosis, but up to 30% of low-stage cases relapse within five years. The benefit of adjuvant chemotherapy for low-stage CCOC (FIGO stage IA-IC1) remains uncertain. This study aimed to identify molecular and immune markers associated with relapse in a well-characterized CCOC cohort. MethodsUsing the Edinburgh Ovarian Cancer Database, we identified 85 CCOC cases. Targeted DNA sequencing assessed genomic alterations and tumour immune infiltration was evaluated using CD3 and CD8 immunohistochemistry on tissue microarrays. Tumours were stratified by stage (IA-IC1, IC2-II, III-IV), and both univariate and multivariate analysis applied for progression-free survival (PFS) included stage, age, genomic features, and immune markers. ResultsCommon genomic alterations included ARID1A (49%) and PIK3CA (42%) mutations, PIK3-AKT pathway perturbations (60%), and mismatch repair-related mutational signatures (25.9%). Genomic and molecular features were not significantly associated with tumour stage; however, low-stage tumours (IA-IC1) were enriched in CD3+ (40% cases) and CD8+ (29% cases) tumour-infiltrating lymphocytes (TILs) compared to higher-stage tumours (IC2-II: 13%/7%; III-IV: 9%/0% cases). In univariate analysis, low CD3+ TIL levels were significantly associated with reduced progression-free survival (HR = 4.4, P = 0.042, 95% CI 1.1-18). ARID1A wild-type status was linked to poorer PFS but only in low-stage tumours HR = 7.2, P = 0.088; 95% CI 0.74-72). Notably, the combination of ARID1A wild-type status and CD3+ depletion identified a high-risk subgroup among low-stage CCOC cases (HR = 11.7, P = 0.050; 95% CI 1-138), highlighting potential as a composite risk marker set. ConclusionsCombined ARID1A mutation and low CD3+ve TIL levels are suggestive of higher recurrence risk in low-stage CCOC patients. These findings support further investigation of targeted therapies or immune checkpoint inhibitors in larger CCOC cohorts. HighlightsO_LIWe report a well-characterized CCOC cohort with rich clinical, genomic and molecular data. C_LIO_LICommon mutations included ARID1A (49%) and PIK3CA (42%), with MSI in 9%, showing no significant enrichment across tumour stages. C_LIO_LILow-stage CCOC has higher levels of CD3+ & CD8+ tumour infiltrating leukocytes than in advanced-stage disease. C_LIO_LIARID1A wild-type tumours with CD3+ TIL depletion represent a high-risk subgroup of low-stage CCOC. C_LIO_LIFindings support further study and highlight potential markers for recurrence risk. C_LI

cancer biology↗

bioRxiv2025

Amino acids activate parallel chemosensory pathways in Drosophila

Amino acids (AAs) are essential dietary macronutrients that impact an organisms fitness in a concentration-dependent manner, but the mechanisms mediating AA detection to drive consumption are less clear. In Drosophila, we identified the full repertoire of taste cells and receptors involved in feeding initiation towards a glutamate-rich AA mixture, tryptone, using in vivo calcium imaging and the proboscis extension response (PER). We found that AA attraction occurs through sweet cells, whereas feeding aversion is mediated through Ionotropic Receptor 94e (IR94e) cells and bitter cells, dependent on concentration. Further, our results corroborate previous findings that ionotropic receptors IR76b, IR51b, and IR94e detect AAs in their respective cell types. Additionally, we describe a new role for the appetitive IR56d receptor and bitter gustatory receptors in detecting AAs. This work establishes a cellular and molecular framework of AA feeding initiation and highlights redundancy in aversive pathways that regulate AA feeding.

neuroscience↗

bioRxiv2024

Operant alcohol self-administration targets GluA2-containing AMPAR expression and synaptic activity in the nucleus accumbens in a manner that drives the reinforcing properties of the drug

Rationale: The positive reinforcing effects of alcohol (ethanol) drive its repetitive use and contribute to alcohol use disorder (AUD). Ethanol alters the expression of glutamate AMPA receptor (AMPAR) subunits in reward-related brain regions, but the extent to which this effect regulates ethanols reinforcing properties is unclear. Objective: This study investigates whether ethanol self-administration changes AMPAR subunit expression and synaptic activity in the nucleus accumbens core (AcbC) to regulate ethanols reinforcing effects in male C57BL/6J mice. Results: Sucrose-sweetened ethanol self-administration (0.81 g/kg/day) increased AMPAR GluA2 protein expression in the AcbC, without effect on GluA1, compared to sucrose-only controls. Infusion of myristoylated Pep2m in the AcbC, which blocks GluA2 binding to N-ethylmaleimide-sensitive fusion protein (NSF) and reduces GluA2-containing AMPAR activity, reduced ethanol-reinforced responding without affecting sucrose-only self-administration or motor activity. Antagonizing GluA2-lacking AMPARs, through AcbC infusion of NASPM, had no effect on ethanol self-administration. AcbC neurons receiving projections from the basolateral amygdala (BLA) showed increased sEPSC area under the curve (a measurement of charge transfer) and slower decay kinetics in ethanol self-administering mice as compared to sucrose. Optogenetic activation of these neurons revealed an ethanol-enhanced AMPA/NMDA ratio and significantly reduced paired-pulse ratio, suggesting elevated GluA2 contributions specifically within the BLA[->]AcbC pathway. Conclusions: Ethanol use upregulates GluA2 protein expression in the AcbC and AMPAR synaptic activity in AcbC neurons receiving BLA projections and enhances synaptic plasticity directly within the BLA[->]AcbC circuit. GluA2-containing AMPAR activity in the AcbC regulates the positive reinforcing effects of ethanol through an NSF-dependent mechanism, highlighting a potential therapeutic target in AUD.

neuroscience↗