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Price, T.

Publications and source records attributed to Price, T..

15 recordsLinked to original sources

A high-quality genome resource for Cercospora cf. flagellaris, a causal agent of Cercospora leaf blight of soybeans

A highly contiguous and complete reference genome of Cercospora cf. flagellaris, the causal agent of foliar disease on many plant hosts including Cercospora leaf blight of soybean, was assembled using a combination of PacBio and Illumina sequencing reads. The genome assembly is 33.72 Mb in length and consists of 14 nuclear scaffolds and one mitochondrial contig. Four scaffolds have telomeric repeats on both ends and represent fully assembled chromosomes, while nine scaffolds represent partially assembled chromosomes with telomeric repeats on one end. The assembly has an N50 of 2.90 Mb and an L50 of 5 scaffolds. Genome annotation identified 11,268 genes, of which 947 and 360 were predicted to encode secreted proteins and effectors, respectively. Additionally, 512 genes were predicted to encode carbohydrate-active enzymes and 60 biosynthetic gene clusters were annotated. Taken together, this annotated genome assembly will be a valuable resource for genomics, host-pathogen interactions, and population biology research in this economically important pathosystem.

genomics↗

Excessive Ca2+-dependent ER-mitochondrial contact stabilization by EFHD1 drives liver injury

Metabolic-associated steatohepatitis (MASH) involves hepatocyte damage that cannot be explained solely by lipid accumulation. Here, to discover injury-specific pathways, we focused on a gene of uncertain function, EF-Hand Domain Family Member D1 (EFHD1), identified in human genome-wide association studies of liver injury but not liver fat. We show that EFHD1, a Ca2+-dependent actin crosslinker, stabilizes endoplasmic reticulum-mitochondria contact sites (ERMCS), detecting spatiotemporal coincidence of inter-organellar proximity and ER Ca2+ release. During MASH, EFHD1 upregulation drives pathological mitochondrial fragmentation via excessive contact persistence. This structural failure promotes mitochondrial double-stranded RNA escape and activation of a maladaptive antiviral PKR-dependent stress response, a causal relationship also supported by Mendelian randomization in humans. Consequently, inhibiting EFHD1 in human and mouse models blunts hepatocyte damage. These findings identify EFHD1 as a Ca2+-dependent ERMCS stabilizer, reveal a hepatocyte-intrinsic injury pathway, and suggest EFHD1 inhibition as a therapeutic strategy.

cell biology↗

Muscle Strength and Size Relationships with Unilateral Progressive Resistance Training

PurposeThis study defines correlative and causal relationships between muscle strength and size before and after unilateral resistance training (RT) in a large cohort of healthy adults, focusing on sex differences within these relationships. MethodsResults from 1233 participants (504 males and 729 females) in a retrospective analysis were included. Maximal voluntary isometric contraction strength (MVC), one-repetition maximum strength (1RM), biceps cross-sectional area (CSA) and elbow flexor volume (VOL) measures of the non-dominant and dominant arm were evaluated from baseline and after 12-wk RT twice per week. Correlations of MVC and VOL and 1RM and VOL were calculated in the whole cohort and within each sex independently. Causal analysis modeling was used to infer mechanistic relationships among variables. ResultsAbsolute muscle strength and size related to one another both at baseline and following training, however correlation strength in each sex were weak. After RT, MVC relative change and VOL relative change correlations were correlated for the whole cohort (r=0.16; p<0.001) and females (r=0.18; p<0.001), but not in males (r=0.11; p=0.07). No significant correlations for relative change in 1RM and VOL were observed for the whole cohort or within sex. Causal discovery determined that change in VOL caused significant change in 1RM (but not MVC) and age was identified as a potential cause. ConclusionsSex differences occur in muscle size and strength relationship adaptations following resistance training, most notably the absence of significant relationships between relative size and strength changes in men. Simpsons paradox bias, where assessing the combined data of males and females (also affecting overall sample size) affects identifies patterns differently than assessing relationships within each sex, may partially explain our findings.

physiology↗

Molecular architecture of human dermal sleeping nociceptors

Human dermal sleeping nociceptors display ongoing activity in neuropathic pain, affecting 10% of the population. Despite advances in rodents, a molecular marker for these mechano-insensitive C-fibers (CMis) in human skin remains elusive, preventing targeted therapy. In this translational Patch-seq study, we combine single-cell transcriptomics following electrophysiological characterization with single-nucleus and spatial transcriptomics from pigs and humans. We functionally identified CMis in pig sensory neurons with patch-clamp using adapted protocols from human microneurography. We identified oncostatin-M-receptor (OSMR) and somatostatin (SST) as marker genes for CMis. Following dermal injection in healthy human volunteers, oncostatin-M, the ligand of OSMR, exclusively modulates CMis. We identified the entire molecular architecture of human dermal sleeping nociceptors, providing new therapeutic targets and the basis for a mechanistic understanding of neuropathic pain. One Sentence SummaryWe identify the molecular architecture and specifically OSMR and SST as molecular markers for human dermal sleeping nociceptors, key players in the generation of neuropathic pain. Short versionIn this Patch-seq study, we identify OSMR and SST as molecular markers for human dermal sleeping nociceptors, key players in the generation of neuropathic pain.

neuroscience↗

Profiling Human iPSC-Derived Sensory Neurons for Analgesic Drug Screening Using a Multi-Electrode Array

Chronic pain is a major global health issue, yet effective treatments are limited by poor translation from preclinical studies to humans. To address this, we developed a high-content screening (HCS) platform for analgesic discovery using hiPSC-derived nociceptors. These cells were cultured on multi-well micro-electrode arrays to monitor activity, achieving nearly 100% active electrodes by week two, maintaining stable activity for at least two weeks. After maturation (28 days), we exposed the nociceptors to various drugs, assessing their effects on neuronal activity, with excellent assay performance (Z values >0.5). Pharmacological tests showed responses to analgesic targets, including ion channels (Nav, Cav, Kv, TRPV1), neurotransmitter receptors (AMPAR, GABA-R), and kinase inhibitors (tyrosine, JAK1/2). Transcriptomic analysis confirmed the presence of these drug targets, although expression levels varied compared to primary human dorsal root ganglion cells. This HCS platform facilitates the rapid discovery of novel analgesics, reducing the risk of preclinical-to-human translation failure. MotivationChronic pain affects approximately 1.5 billion people worldwide, yet effective treatments remain elusive. A significant barrier to progress in analgesic drug discovery is the limited translation of preclinical findings to human clinical outcomes. Traditional rodent models, although widely used, often fail to accurately predict human responses, while human primary tissues are limited by scarcity, technical difficulties, and ethical concerns. Recent advancements have identified human induced pluripotent stem cell (hiPSC)-derived nociceptors as promising alternatives; however, current differentiation protocols produce cells with inconsistent and physiologically questionable phenotypes. To address these challenges, our study introduces a novel high-content screening (HCS) platform using hiPSC-derived nociceptors cultured on multi-well micro-electrode arrays (MEAs). The "Anatomic" protocol, used to generate these nociceptors, ensures cells with transcriptomic profiles closely matching human primary sensory neurons. Our platform achieves nearly 100% active electrode yield within two weeks and demonstrates sustained, stable activity over time. Additionally, robust Z factor analysis (exceeding 0.5) confirms the platforms reliability, while pharmacological validation establishes the functional expression of critical analgesic targets. This innovative approach improves both the efficiency and clinical relevance of analgesic drug screening, potentially bridging the translational gap between preclinical studies and human clinical trials, and offering new hope for effective pain management.

neuroscience↗

Leveraging Crosslinker Diffusion to Template Stiffness Gradients in Alginate Hydrogels

Mechanobiology drives many important cell biological behaviors such as stem cell differentiation, cancer drug resistance and cell migration up stiffness gradients, a process called durotaxis. The development of 3D hydrogel systems with tunable 2D mechanical gradient patterns affords the ability to study these mechanosensitive cell behaviors to understand cancer invasion or enhance wound healing through directed migration. In this paper, we developed an approach to spatially imprint within alginate hydrogels, gradients in mechanical properties that can be used to probe mechanobiology. Stencils were easily designed and fabricated using a common craft cutter to control the presentation of a calcium crosslinking solution to alginate gels. Different stencil shapes result in different gradients in opacity that can be imprinted into both thick and thin alginate gels of arbitrary 2D shape. The steepness of the opacity gradient as well as the maximum opacity can be controlled based on reproducible crosslinking kinetics regulated through calcium concentration and gradient developing time. Calcium crosslinking results in both opacity changes as well as increases in elastic modulus in the bulk hydrogel. Opacity correlates with elastic modulus, allowing it to be used as a proxy for local elastic modulus. Functionalized alginate gels with collagen and imprinting stiffness gradients within them resulted in cell invasion that was spatially dependent, where stiffer regions facilitated deeper invasion of breast cancer cells. Consequently, this stenciling approach represents a facile way to control stiffness gradients in alginate gels in order to study mechanosensitive cellular behavior. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=45 SRC="FIGDIR/small/599742v2_ufig1.gif" ALT="Figure 1"> View larger version (14K): org.highwire.dtl.DTLVardef@1182404org.highwire.dtl.DTLVardef@1e4bfb1org.highwire.dtl.DTLVardef@e52778org.highwire.dtl.DTLVardef@8237bd_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗

Ant impacts on global patterns of bird elevational diversity

Across the worlds mountains, elevation-species richness relationships are highly variable. Here, using data on bird species elevational distributions from all 46 of the worlds major mountain ranges, bird species dietary traits, and the distribution of the low-elevation ant genus Oecophylla, we show that global patterns in bird elevational diversity are likely to be affected by competition with ants. Oecophylla is an exceptionally abundant and aggressive predator of invertebrates, which preys on the same species that sympatric invertivorous bird species feed on. In mountain ranges with Oecophylla present in the foothills, maximum species richness of invertivorous birds occurs, on average, at 960m, [~]450m higher than in mountain ranges without Oecophylla. Further, in mountain ranges with Oecophylla, species richness of invertivorous birds increases initially with with elevation to produce a mid-elevation peak in invertivore bird species richness. Where Oecophylla is absent, invertivore bird species richness generally shows monotonic declines with increasing elevation. We attribute the pattern to the following mechanism: first, Oecophylla reduces prey density for invertivorous birds; second, low invertebrate prey abundance reduces invertivorous bird density and third, lower bird density is correlated with lower bird species richness. Because invertivores dominate montane bird communities, global elevational bird diversity patterns are also driven by Oecophylla. The findings emphasize how competitive interactions between distantly related taxa set geographical range limits.

ecology↗

Genetic drift and genome reduction in the plant pathogen Candidatus Liberibacter solanacearum shapes a new enzyme in lysine biosynthesis.

The effect of population bottlenecks and genome reduction on enzyme function is poorly understood. Candidatus Liberibacter solanacearum is a bacterium with a reduced genome that is transmitted vertically to the egg of an infected psyllid--a population bottleneck that imposes genetic drift and is predicted to affect protein structure and function. Here, we define the effects of genome reduction and genetic drift on the function of Ca. L. solanacearum dihydrodipicolinate synthase (CLsoDHDPS), which catalyses the committed branchpoint reaction in diaminopimelate and lysine biosynthesis. We demonstrate that CLsoDHDPS is expressed in Ca. L. solanacearum and expression is increased [~]2-fold in the insect host compared to in planta. CLsoDHDPS has increased aggregation propensity, implying mutations have destabilised the enzyme but are compensated for through elevated chaperone expression and a stabilised oligomeric state. CLsoDHDPS uses a ternary-complex kinetic mechanism, which is unique among DHDPS enzymes, has unusually low catalytic ability, but an unusually high substrate affinity. Structural studies demonstrate that the active site is more open, and the structure of CLsoDHDPS with both pyruvate and the substrate analogue succinic-semialdehyde reveals that the product is both structurally and energetically different and therefore evolution has in this case fashioned a new enzyme. Our study reveals the effects of genome reduction and genetic drift on the function of essential enzymes and provides insights on bacteria-host co-evolutionary association. We suggest that bacteria with endosymbiotic lifestyles present a rich vein of interesting enzymes useful for understanding enzyme function and/or informing protein engineering efforts.

evolutionary biology↗

A selfish genetic element and its suppressor causes gross damage to testes in a fly

Selfish genetic elements (SGEs), specifically X-chromosome meiotic drive (XCMD), create huge conflicts within a hosts genome and can have profound effects on fertility. Suppressors are a common evolutionary response to XCMD to negate its costs. However, whether suppressors themselves can cause negative non-target effects remains understudied. Here, we examine whether the intragenomic conflicts created by XCMD and its suppressor affect gonad morphology in Drosophila subobscura. We found significant differences in testes, seminal vesicle, and accessory gland size depending on whether a male carried a non-driving X chromosome, an XCMD, and if the XCMD was suppressed. We also found the first evidence of abnormal testes development that is specifically associated with a suppressor of XCMD. Unlike other studies, our evidence suggests that XCMD in D. subobscura creates major abnormalities to male gonads. These abnormalities are most frequent if both XCMD and its suppressor are both present. While costs of suppression have importance in theoretical models, they have largely been ignored in empirical XCMD systems. Overall, this study highlights that genetic conflict, created by SGEs and their suppressors, is a potent evolutionary force that can have major impacts on gonad development and gametogenesis.

evolutionary biology↗

Cellular and Molecular Organization of the Rhesus Macaque Dorsal Horn with a Comparison to Mouse

Key mechanisms underlying chronic pain occur within the neural circuitry of the dorsal horn. Recent genome-wide association studies (GWAS) have identified genetic variants associated with the predisposition to chronic pain. However, most of these variants lie in regulatory non-coding regions that have so far not been linked to spinal cord function. Here, we take a multi-species approach to determine whether chronic pain variants impact regulatory elements of dorsal horn neurons. We first built a more comprehensive single cell atlas; filling gaps by generating a high-quality Rhesus macaque atlas and integrating it with human and mouse. With cellular-resolution spatial transcriptomics, we mapped the laminar distributions of the resulting species-conserved neuron subtypes, uncovering an unexpected organization. Lastly, we generated a mouse single-nucleus open chromatin atlas to partition the heritability of chronic pain traits. From this, we identified strong, selective associations between specific, conserved neuron subtypes and major forms of chronic pain.

neuroscience↗

A selective adenylyl cyclase 1 inhibitor relieves pain without causing tolerance

Adenylyl cyclases (ACs) catalyze the production of the second messenger cyclic adenosine monophosphate from adenosine triphosphate. Among the ten different AC isoforms, studies with knockout animals indicate that inhibition of AC1 can relieve pain and reduce behaviors linked to opioid dependence. We previously identified ST034307 as a selective inhibitor of AC1. The development of an AC1-selective inhibitor now provides the opportunity to further study the therapeutic potential of inhibiting this protein in pre-clinical animal models of pain and related adverse reactions. In the present study we have shown that ST034307 relieves pain in mouse models of formalin-induced inflammatory pain, acid-induced visceral pain, and acid-depressed nesting. In addition, ST034307 did not cause analgesic tolerance after chronic dosing. We also show that the compound is restricted to the periphery following subcutaneous injections and report the predicted molecular interaction between ST034307 and AC1. Our results indicate that AC1 inhibitors represent a promising new class of analgesic agents that treat pain and appear to produce less adverse effects than currently-used opioids.

pharmacology and toxicology↗

Temperatures that sterilise males better predict global distributions of species than lethal temperatures

Predicting how biodiversity will respond to increased temperatures caused by climate change is vital. However, our understanding of the traits that determine species response to thermal stress remains incomplete. Laboratory measurements of lethal temperatures have successfully been used to predict global species distributions and the vulnerability of species to future climate change. However, although it has long been known that fertility is sensitive to heat stress, temperatures that cause sterility have not been incorporated into predictions about how climate change will affect biodiversity. Here we show that male sterility temperatures predict the global distributions of 43 species of Drosophila substantially better than their lethal temperatures. This strongly suggests that thermal limits to reproduction can underpin how temperature affects species distributions. High temperatures impair male fertility across a broad range of animals and plants, so many organisms may be more vulnerable to high temperatures than currently expected.

ecology↗

Accurate cell tracking and lineage construction in live-cell imaging experiments with deep learning

While live-cell imaging is a powerful approach to studying the dynamics of cellular systems, converting these imaging data into quantitative, single-cell records of cellular behavior has been a longstanding challenge. Deep learning methods have proven capable of performing cell segmentation--a critical task for analyzing live-cell imaging data--but their performance in cell tracking has been limited by a lack of dynamic datasets with temporally consistent single-cell labels. We bridge this gap through the integrated development of labeling and deep learning methodology. We present a new framework for scalable, human-in-the-loop labeling of live-cell imaging movies, which we use to label a large collection of movies of fluorescently labeled cell nuclei. We use these data to create a new deep-learning-based cell-tracking method that achieves state-of-the-art performance in cell tracking. We have made all of the data, code, and software publicly available with permissive open-source licensing through the DeepCell projects web portal https://deepcell.org.

systems biology↗

Nociceptor translational profiling reveals the RagA-mTORC1 network as a critical generator of neuropathic pain

Pain sensing neurons, nociceptors, are key drivers of neuropathic pain. We used translating ribosome affinity purification (TRAP) to comprehensively characterize up-and down-regulated mRNA translation in Scn10a-positive nociceptors in chemotherapy-induced neuropathic pain. We provide evidence that an underlying mechanism driving these changes in gene expression is a sustained mTORC1 activation driven by MNK1-eIF4E signaling. RagA, a GTPase controlling mTORC1 activity, is identified as a novel target of MNK1-eIF4E signaling, demonstrating a new link between these distinct signaling pathways. Neuropathic pain and RagA translation are strongly attenuated by genetic ablation of eIF4E phosphorylation, MNK1 elimination or treatment with the MNK inhibitor eFT508. We reveal a novel translational circuit for the genesis of neuropathic pain with important implications for next generation neuropathic pain therapeutics.\n\nOne Sentence SummaryCell-specific sequencing of translating mRNAs elucidates signaling pathology that can be targeted to reverse neuropathic pain

neuroscience↗

Strong hybrid male incompatibilities impede the spread of a selfish chromosome between populations of a fly.

Meiotically driving sex chromosomes manipulate gametogenesis to increase their transmission at a cost to the rest of the genome. The intragenomic conflicts they produce have major impacts on the ecology and evolution of their host species. However their ecological dynamics remain poorly understood. Simple population genetic models predict meiotic drivers will rapidly reach fixation in a population and spread across a landscape. In contrast, natural populations commonly show spatial variation in the frequency of drivers, with drive present in clines or mosaics across species ranges. For example, Drosophila subobscura harbours a Sex Ratio distorting drive chromosome (\"SRs\") at 15-25% frequency in North Africa, present at less than 2% frequency in adjacent Southern Spain and absent in other European populations. Here, we investigate the forces preventing the spread of the driver northward. We show that SRs has remained at a constant frequency in North Africa, and failed to spread in Spain. We find strong evidence in favour of our first hypothesis, genetic incompatibility between SRs and Spanish autosomal background. When we cross SRs from North Africa onto Spanish genetic backgrounds we observe strong SRs specific incompatibilities in hybrids. The incompatibilities increase in severity in F2 male hybrids, leading to almost complete infertility. We find no evidence supporting a second hypothesis, that there is resistance to drive in Spanish populations. We conclude that the source of the stepped frequency variation is genetic incompatibility between the SRs chromosome and the genetic backgrounds of the adjacent population, preventing SRs spreading northward. The low frequency of SRs in South Spain is consistent with recurrent gene flow across the Strait of Gibraltar combined with selection against the SRs element through genetic incompatibility. This demonstrates that incompatibilities between drive chromosomes and naive populations can prevent the spread of drive between populations, at a continental scale.

evolutionary biology↗