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Wang, D.

Publications and source records attributed to Wang, D..

At least 181 records · Page 10Linked to original sources

Accurate detection and quantification of single-base m6A RNA modification using nanopore signals with multi-view deep learning

N6-methyladenosine (m6A) is a crucial epitranscriptomic mark. While Nanopore Direct RNA Sequencing (DRS) enables transcriptome-wide detection, most existing methods neglect or lack the capacity to effectively process the intrinsically variable-length raw signals generated by DRS reads.Here, we present MultiNano, a multi-view deep learning framework that converts variable-length raw signals into image-like feature representations, effectively resolving the length inconsistency problem. By integrating raw signal and basecalling features, MultiNano enables accurate and comprehensive transcriptome-wide detection of m6A modifications. Our model achieved state-of-the-art (SOTA) performance in various tasks, including site-level prediction, read-level prediction, cross-species transfer learning, and modification rate estimation. Furthermore, the false positive control strategy implemented in MultiNano significantly enhances the models robustness and predictive accuracy, offering a powerful alternative to traditional thresholding-based filtering algorithms. Collectively, our approach provides novel insights for the absolute quantification and single-base resolution of RNA modifications.

bioinformatics↗

Asymmetric life-history trade-offs shape sex-biased longevity patterns

Sex differences in ageing and lifespan are widespread across taxa, yet their evolutionary causes remain debated. A leading hypothesis suggests these differences are adaptive and driven by sex-specific life-history trade-offs, but formal theoretical support is lacking. To address this, we developed a mathematical model to investigate how such trade-offs shape lifespan evolution in a monogamous mating system. In the model, individuals evolve to optimise a trade-off between reproduction and survival - mediated by mating opportunities in males and offspring production in females. By systematically varying trade-off strengths, we show that either sex can evolve greater longevity, but male-biased longevity evolves under a broader set of conditions - consistent with patterns in monogamous species. This asymmetry arises because female longevity is more constrained: the trade-off between offspring production and survival directly affects the fertility of both sexes. In contrast, the male trade-off for mating opportunities has a weaker indirect effect on female fertility, allowing selection to more readily favour longer male lifespans. We also show that extrinsic density-dependent mortality can disproportionately affect the intrinsically longer-living sex, and obscure the magnitude of this evolved difference. Together, our results provide new theoretical insights into the adaptive bases of sex-biased longevity and highlight the importance of life-history trade-offs in shaping lifespan evolution.

evolutionary biology↗

Overcoming breeding constraints in polyploid oat from evolutionary insights

Polyploidy provides adaptive advantages in plants by buffering deleterious mutations1,2. While polyploidization can enhance agronomic traits such as increased biomass, known as the gigas effect1-4, increasing genetic gain in polyploid crops remains a critical but difficult goal due to the difficulty in dissecting complex trait inheritance5,6. Here we present chromosome-scale genome assemblies for 26 Avena taxa, spanning diploid, tetraploid, and hexaploid lineages. We traced four independent polyploidization events across the genus, including the formation of A. agadiriana as an allotetraploid (AgAgAg'Ag'), and revealed a reticulate evolutionary history shaped by gene flow involving four subgenomes (A, B, C, D), for example, the hybrid speciation of A. hirtula. Transcriptomic analysis of 286 samples across 11 tissues, combined with deleterious mutation analysis from a cultivated population of 112 accessions, showed that polyploidization led to widespread functional redundancy among homoeologs, supporting a genome-wide buffering effect. However, derived allele frequency analysis revealed that, while disrupting functional genes may yield desirable traits, the buffering effect impedes the fixation of beneficial loss-of-function mutations and thereby limits breeding efficiency. Based on these integrative analyses, we propose breeding strategies to circumvent these limitations by targeting beneficial loss-of-function alleles within the complex polyploid background of oat. Our study highlights broader challenges in the improvement of polyploid crops and provides a foundation for future breeding strategies.

evolutionary biology↗

ProtLoc-GRPO: Cell line-specific subcellular localization prediction using a graph-based model and reinforcement learning

Subcellular localization prediction is crucial for understanding protein functions and cellular processes. Subcellular localization is dependent on tissue and cell lines derived from different cell types. Predicting cell line-specific subcellular localization using the information of protein-protein interactions (PPIs) offers deeper insights into dynamic cellular organization and molecular mechanisms. However, many existing PPI networks contain systematic errors that limit prediction accuracy. In this study, we propose a reinforcement learning approach, ProtLoc-GRPO, to enhance subcellular localization prediction by optimizing the structure of the underlying PPI network. ProtLoc-GRPO learns to rank and retain the most informative PPI edges to maximize the macro-F1 score for cell line-specific subcellular localization. Our approach yields a 7% improvement in macro-F1 score over the baseline. We further evaluate its robustness across various edge pruning rates and benchmark it against conventional pruning strategies. Results show that our proposed method consistently outperforms existing approaches. To our knowledge, this work represents the first study to predict cell line-specific protein subcellular localization and the first application of the Group Relative Policy Optimization (GRPO) framework to a graph-based model for bioinformatics tasks.

bioinformatics↗

Maturation of Dorsal Association Tracts during Preadolescence Links to Concurrent and Future Cognitive Performance and Transdiagnostic Psychopathology

Many psychiatric disorders begin during adolescence, coinciding with the rapid development of brain white matter (WM). However, it remains unclear whether deviations from normal WM maturation during this age period contribute to the development of psychopathology. In this study, we developed and validated normative models of brain age based on specific WM tracts using three large-scale developmental datasets (a total of [~]10,000 subjects). We found that tract-specific deviations in WM development of association and limbic/subcortical systems were linked to concurrent cognition and psychopathology. The spatial pattern of the association system aligned closely with distributions of high-order brain networks, and with mitochondrial content and respiratory capacity. The maturation of the association system contributed significantly to better cognitive performance assessed two or three years later. Importantly, delayed WM development especially in dorsal association tracts predicted psychiatric disorders across diagnoses and disorder onset over a 2-year follow-up. By identifying tract-specific WM development during preadolescence as a predictor of cognitive capacity and psychiatric disorder risks, this study provides a valuable framework for tracking individualized brain maturation and understanding the neurobiological underpinnings of cognitive performance and transdiagnostic psychopathology.

neuroscience↗

Structural basis of DNA N6-adenine methylation in eukaryotes

As a transcription-associated epigenetic mark abundantly present in many unicellular eukaryotes, DNA N6-adenine methylation (6mA) is maintained by the AMT1 complex. However, the structure-function relationship of the AMT1 complex remains to be fully elucidated. Here, we employ AlphaFold3 (AF3) for de novo structural modeling of the AMT1 complex, complemented by molecular dynamics simulations. Functional relevance of key structural features, especially those of the AMT1 ternary complex with the double-stranded DNA (dsDNA) substrate and the cofactor, are validated by extensive mutagenesis, both in vivo and in vitro. Our analysis reveals the structural basis for DNA substrate recognition, base flipping, and catalysis in this prototypical eukaryotic DNA 6mA-methyltransferase. It also allows us to delineate the reaction pathway for processive methylation involving translocation of the AMT1 complex along the dsDNA. As the active site is conserved across the MT-A70 family of eukaryotic N6-adenine methyltransferases, the structural insight will facilitate rational design of specific inhibitors.

molecular biology↗

Molecular and cellular processes disrupted in the early postnatal Down syndrome prefrontal cortex

Down syndrome is the most common genetic cause of intellectual disability and is characterized by early-onset delays in motor, cognitive, and language development. The molecular mechanisms underlying these neurodevelopmental impairments remain poorly understood. Here, we utilized single-nucleus multiomic sequencing to simultaneously profile gene expression and chromatin accessibility in the Down syndrome prefrontal cortex during early postnatal development, a critical period for synaptogenesis, neural maturation, and developmental neuroimmune interactions. Our findings reveal widespread dysregulation of chromatin accessibility and gene expression, with deficits spanning metabolic and synaptic pathways, oligodendrocyte lineage progression, and a pronounced neuroinflammatory signature. We present a molecular atlas of Down syndrome neuropathology at a critical stage of brain development, highlighting convergent neurodevelopmental and neurodegenerative pathways and informing potential targeted therapies for Down syndrome-associated neuroinflammation.

neuroscience↗

Pre-stimulus alpha power modulates trial-by-trial variability in theta rhythmic multisensory entrainment strength and theta-induced memory effect

Binding multisensory information into episodic memory depends partly on the timing of the hippocampal theta rhythm which provides time windows for synaptic modification. In humans, theta rhythmic sensory stimulation (RSS) enhances episodic memory when the stimuli are synchronised across the visual and auditory domain compared to when they are out-of-synchrony. However, recent studies show mixed evidence if the improvement in episodic memory is the result of modulating hippocampal theta activity. In the current study, we investigated whether pre-stimulus brain state could explain part of this variance in the neural and behavioural effects induced by the RSS, via recording participants brain activity with MEG during a multisensory theta RSS memory paradigm. Our findings suggest that pre-stimulus alpha power modulates entrainment strength in sensory regions, which in turn predicts subsequent memory formation. These findings suggest that for non-invasive brain stimulation tools to be effective it is crucial to consider brain-state dependent effects.

neuroscience↗

Pathogenic fungus exploits the lateral root regulators to induce pluripotency in maize shoots

Biotrophic plant pathogens secrete effector molecules to redirect and exploit endogenous signaling and developmental pathways in their favor. The biotrophic fungus Ustilago maydis causes galls on all aerial parts of maize. However, identification and characterization of the responsible gall-inducing effectors and corresponding plant signaling pathway(s) are largely elusive. Here we reveal molecular components acting downstream of a group of plant TOPLESS (TPL)- corepressor interacting fungal effectors that are directly involved in gall formation. We classify these effectors into two classes based on distinct phenotypic responses when individually expressed in planta. While class I responses are characterized by leaf chlorosis, transgenic plants expressing class II TPL-interacting protein (Tip) effectors show a derepression of the AtARF7/AtARF19 branch of auxin signaling, resulting in pluripotent calli formation without the external addition of phytohormones. Subsequent comparative transcriptomics in maize also demonstrates a highly significant overlap of genes up-regulated during U. maydis-triggered leaf gall formation and during the developmental initiation of lateral root formation. This suggests that U. maydis can hijack the lateral root initiation pathway to induce galls in maize shoots. We demonstrate that underlying this is the transcriptional upregulation of downstream LATERAL ORGAN BOUNDARIES DOMAIN (LBD) transcription factors. Maize mutants in two LBD genes (ra2, rtcs) led to significantly reduced gall formation following U. maydis infection on homozygous mutants. This study reveals a set of dominantly acting cell proliferation-inducing fungal effectors and provides novel insight into plant developmental pathways that can be hijacked by biotrophic pathogens to induce gall formation.

plant biology↗

Interaction of Wnt and SHH gradients synchronizes cell cycle 1 exit and differentiation

Classic models of the French flag problem depict sharp cell-type boundaries emerging from threshold responses to morphogen gradients. Yet, how such boundaries arise during dynamic cell-state transitions remains unclear. We use hair follicle dermal condensates to study a sharp cell-type transition in which proliferative progenitors synchronously undergo cell-cycle exit and molecular differentiation. Using genetic and genomic approaches, we show that Wnt and Hedgehog signaling interact to coordinate the timing of these processes. When their activities are temporally aligned, intermediate transitional states are compressed through cell-cycle exit, producing a sharp cell-type boundary; when misaligned, transitional states expand, yielding fuzzy borders. Mechanistically, elevated Wnt activity promotes cell-cycle exit by regulating chromatin binding of the Hedgehog mediator GLI3. Hedgehog signaling induces differentiation genes in a Wnt-dependent manner and simultaneously elevates Wnt activity, aligning arrest and differentiation in time. These findings reveal a mechanism wherein morphogen interactions coordinate transitions to generate precise cell-type boundaries.

developmental biology↗

Using Artificial Intelligence to Assess Cross-Species Transmission Potential of Influenza A Virus

Influenza A viruses (IAVs) pose pandemic threats through cross-species transmission, yet predicting their adaptive evolution remains challenging. We introduced Influenza A virus Adaptability to host X (FluAdaX), a deep learning framework that integrates a moving average-equipped gated attention mechanism using full-genome sequences. FluAdaX demonstrated robust host classification performance across endemic IAV strains, and outperformed traditional models in detecting avian-to-human transmission. Spillover score and adaptability score were introduced to evaluate host shift risk, which prioritized variants with elevated human adaptation potential, such as H7N9, H9N2 avian IAVs, and H1N1 swine IAVs. Besides HA and NA genes, PB2 and NS genes were found critical for zoonosis. Potential molecular markers associated with avian/human tropism were identified across PB2 and NS genes using XGBoost. FluAdaX provided a dynamic framework to decode IAV host adaptation, enabling real-time risk assessment of cross-species transmission of emerging IAV variants.

bioinformatics↗

Cross-talk between RNA secondary and three-dimensional structure prediction: a comprehensive study

In recent years, various computational methods have been developed to predict the three-dimensional (3D) structures of RNAs. Due to its hierarchical folding property, RNA secondary (2D) structure is usually used as input for 3D structure prediction to improve accuracy and efficiency. However, the extent to which the accuracy of input 2D structure affects the performance of 3D structure prediction remains to be further investigated. Additionally, whether and how the input base-pairing interactions are modified during the 3D structure modeling process is another question worth exploring. To address these issues, here we comprehensively benchmark five representative 3D structure prediction models on extensive datasets, using 2D structures of varied accuracies as input. Our results indicate that there is a pervasive cross-talk between RNA 2D and 3D structure predictions, where the performance dependence of 3D structure prediction on the accuracy of input 2D structure is closely associated with the 3D models ability to modify the input base-pairing interactions during structure modeling. Furthermore, we also observed that RNA 3D structure prediction performance is more sensitive to the occurrence of false positive base pairs in the input 2D structure than to true positive base pairs, suggesting a worthy direction to further improve the model performance. Author summaryThree-dimensional (3D) structural modeling of RNAs with large sizes and complex topologies remains challenging despite the availability of (predicted) 2D structures as constraints. Exploring the potential cross-talk between 2D and 3D structure predictions is a worthy direction to improve the performance of RNA structure modeling. In this study, we found that all tested popular RNA 3D structure prediction models were able to modify the original base pairing interactions contained in the input 2D structure during the 3D modeling process. Especially, all of these models presented increased F1-score for the optimal combination of RNA 2D and 3D structure prediction models. The results suggest that a worthwhile direction to further improve the performance of RNA 3D structure prediction is to minimize the incidence of incorrectly predicted base pairing interactions during modeling process without compromising or even improving the presence of correct interactions in the input 2D structure.

biophysics↗

Population-specific brain charts reveal Chinese-Western differences in neurodevelopmental trajectories

Human brain charts provide unprecedented opportunities for decoding neurodevelopmental milestones and establishing clinical benchmarks for precision brain medicine 1-7. However, current lifespan brain charts are primarily derived from European and North American cohorts, with Asian populations severely underrepresented. Here, we present the first population-specific brain charts for China, developed through the Chinese Lifespan Brain Mapping Consortium (Phase I) using neuroimaging data from 43,037 participants (aged 0-100 years) across 384 sites nationwide. We establish the lifespan normative trajectories for 296 structural brain phenotypes, encompassing global, subcortical, and cortical measures. Cross-population comparisons with Western brain charts (based on data from 56,339 participants aged 0-100 years) reveal distinct neurodevelopmental patterns in the Chinese population, including prolonged cortical and subcortical maturation, accelerated cerebellar growth, and earlier development of sensorimotor regions relative to paralimbic regions. Crucially, these Chinese-specific charts outperform Western-derived models in predicting healthy brain phenotypes and detecting pathological deviations in Chinese clinical cohorts. These findings highlight the urgent need for diverse, population-representative brain charts to advance equitable precision neuroscience and improve clinical validity across populations.

neuroscience↗

Desert Hedgehog mediates stem Leydig cell differentiation through Ptch2/Gli1/Sf1 signaling axis

Desert Hedgehog (Dhh) mutations cause Leydig cell dysfunction, yet the mechanisms governing Leydig lineage commitment through Dhh-mediated receptor selectivity, transcriptional effector specificity, and steroidogenic coupling remain elusive. In this study, using CRISPR/Cas9-mediated gene knockout and stem Leydig cells (SLCs) transplantation, we identified a critical Dhh/Patched 2 (Ptch2)/Glioma-associated oncogene homolog 1 (Gli1)/steroidogenic factor 1 (Sf1) signaling axis essential for SLC differentiation in Nile tilapia (Oreochromis niloticus). Dhh deficiency resulted in defective adult Leydig cells and androgen insufficiency. Rescue experiments involving 11-ketotestosterone administration and a Dhh agonist treatment, combined with SLCs transplantation, demonstrated that Dhh regulates SLC differentiation, not survival. In vitro knockout of ptch1 and ptch2 in SLCs revealed that Ptch2 likely acts as the functional receptor for Dhh. This was further supported by in vivo genetic rescue experiments, where ptch2 mutation did not impair testicular development, yet completely rescued the testicular defects in dhh mutants--consistent with Ptch2 acting as an inhibitory receptor whose loss alleviates Dhh pathway suppression. Luciferase assays in Gli-knockout SLCs demonstrated that Gli1 acts as the primary transcriptional effector, and transactivates sf1 expression. Additionally, functional transplantation assays confirmed that Sf1 is indispensable for SLCs differentiation, as Sf1-overexpressing SLCs rescued differentiation, whereas sf1-mutant SLCs failed. Overall, our work delineates the Dhh-Ptch2-Gli1-Sf1 axis and provides fundamental insights into the endocrine regulation of Leydig cell lineage development. HighlightsO_LIDhh regulates the differentiation of SLCs rather than their survival C_LIO_LIPtch2 acts as the functional receptor for Dhh signaling in SLCs C_LIO_LIGli1 is the principal transcriptional activator for Dhh signaling in SLCs C_LIO_LISf1 is the critical downstream effector of Gli1 in SLCs differentiation C_LI

developmental biology↗

Advancing Fair and Explainable Machine Learning for Neuroimaging Dementia Pattern Classification in Multi-Ethnic Populations

Dementia, a degenerative disease affecting millions globally, is projected to triple by 2050. Early and precise diagnosis is essential for effective treatment and improved quality of life. However, current diagnostic approaches frequently demonstrate inconsistent precision and impartiality, particularly among diverse cultural groups. This study investigates performance discrepancies in dementia classification among White American, African American, and Hispanic populations. We reveal significant cross-group bias, particularly when models trained on one group are tested on another. To address this, we introduce a novel combination of few-shot learning and domain alignment to improve model adaptability across underrepresented populations. Our results show that these techniques substantially reduce inter-group performance gaps, especially between White American and Hispanic cohorts. This finding highlights the crucial need for fairness-aware strategies and the inclusion of diverse populations in training data to ensure accurate and equitable dementia diagnoses.

neuroscience↗

Complex I Governs Iron Levels in Bat Mitochondria to Couple Respiration with Lipid Metabolism

The evolution of mitochondrial respiration has been implicated in the remarkable adaptations of bats, including powered flight, longevity and viral tolerance. However, the mechanisms coordinating mitochondrial respiration with lipid metabolism--a critical energy source for flight--remain poorly understood. Here, we discovered that complex I inhibition triggered iron overload into bat mitochondria, inducing a burst of reactive oxygen species (ROS). This iron translocation relied on the VDAC-MCU axis and mitochondrial membrane potential. Intriguingly, disrupting VDAC oligomerization enhanced iron uptake in a complex I-dependent manner. Mitochondrial iron translocation perturbed fatty acid oxidation and upregulated linoleic acid species, which promoted the reversible accumulation of lipid droplets, suggesting metabolic plasticity crucial for bat energetics. Our findings establish complex I as a pivotal regulatory hub that directly couples respiratory efficiency to lipid metabolism by governing mitochondrial iron levels. This mechanism may represent a key evolutionary adaptation supporting the unique metabolic demands of bat physiology. HIGHLIGHTSComplex I inhibition induces unique mitochondrial ROS burst in bat cells. Mitochondrial iron overload is the primary trigger of complex I-linked ROS burst. VDAC-MCU axis couples membrane potential to drive mitochondrial iron influx. Mitochondrial iron translocation remodels lipid metabolism in bat cells.

cell biology↗

BOOPTHAT: An inexpensive and scalable system for spatiotemporal activation of heat-shock transgenes in zebrafish

We present the BOOPTHAT (Batch-Operating Optically Powered Targeted Heater for Activating Transgenes) as a low-cost system for activating heat-shock inducible transgenes with spatiotemporal control in multiple zebrafish embryos at a time. Gaining finer spatiotemporal control over gene expression is critical for unraveling the regulatory networks that coordinate embryogenesis. While the heat-shock inducible gene expression system is a widely used tool for controlling temporal transgene expression, its applicability in spatiotemporal control is limited. By adding a level of spatial control onto this well-established system, we take advantage of the existing infrastructure surrounding the HS induction system and introduce new ways to use the multitude of existing lines. The BOOPTHAT system is built from 3D printed components and inexpensive consumer parts. Independent 3D printed micromanipulators are used to position optical fiber probes. When coupled to a light source, the probes are heated photothermally and are used to perform targeted gene activation in multiple samples at a time. We demonstrate the capabilities of our system and highlight some areas of research that stand to benefit from this frugal and effective system.

developmental biology↗

Gene therapies alleviate absence epilepsy associated with Scn2a deficiency in DBA/2J mice

Mutations in the voltage-gated sodium channel gene SCN2A, which encodes the NaV1.2 channel, cause severe epileptic seizures. Patients with SCN2A loss-of-function (LoF) mutations, such as protein-truncating mutations, often experience later-onset and drug-resistant epilepsy, highlighting an urgent unmet clinical need for new therapies. We previously developed a gene-trap Scn2a (Scn2agt/gt) mouse model with a global NaV1.2 reduction in the widely used C57BL/6N (B6) strain. Although these mice display multiple behavioral abnormalities, EEG recordings indicated only mild epileptiform discharges, possibly attributable to the seizure-resistant characteristics associated with the B6 strain. To enhance the epileptic phenotype, we derived congenic Scn2agt/gt mice in the seizure-susceptible DBA/2J (D2J) strain. Notably, we found that these mice exhibit prominent spontaneous absence seizures, marked by both short and long spike-wave discharges (SWDs). Restoring NaV1.2 expression in adult mice substantially reduced their SWDs, suggesting the possibility of SCN2A gene replacement therapy during adulthood. RNA sequencing revealed significant alterations in gene expression in the Scn2agt/gt mice, in particular a broad downregulation of voltage-gated potassium channel (KV) genes, including KV1.1. The reduction of KV1.1 expression was further validated in human cerebral organoids with SCN2A deficiency, highlighting KV1.1 as a promising therapeutic target for refractory seizures associated with SCN2A dysfunction. Importantly, delivery of exogenous human KV1.1 expression via adeno-associated virus (AAV) in D2J Scn2agt/gt mice substantially reduced absence seizures. Together, these findings underscore the influence of mouse strain on seizure severity and highlight the potential of targeted gene therapies for treating SCN2A deficiency-related epilepsies. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=91 SRC="FIGDIR/small/657652v1_ufig1.gif" ALT="Figure 1"> View larger version (18K): org.highwire.dtl.DTLVardef@35374eorg.highwire.dtl.DTLVardef@1c22197org.highwire.dtl.DTLVardef@2b4582org.highwire.dtl.DTLVardef@e06e68_HPS_FORMAT_FIGEXP M_FIG C_FIG In briefScn2a deficiency leads to absence seizures in D2J mice and neuronal hyperexcitability with compensatory KV reduction; restoring NaV1.2 or introducing human KV1.1 reduces seizure burden. HighlightsO_LIScn2a deficiency induces robust absence seizures in the DBA/2J but not the C57BL/6N strain. C_LIO_LICortical neurons in adult DBA/2J mice with Scn2a deficiency exhibit intrinsic hyperexcitability. C_LIO_LISevere Scn2a deficiency leads to downregulation of multiple potassium channel genes. C_LIO_LIGenetic restoration of NaV1.2 expression alleviates spike-wave discharges (SWDs). C_LIO_LIAAV-mediated human KV1.1 delivery substantially reduced absence seizures, demonstrating the therapeutic potential of targeted gene therapy. C_LI

neuroscience↗