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Wu, J.

Publications and source records attributed to Wu, J..

At least 217 records · Page 12Linked to original sources

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↗

H3K4me1 directs H3K36me2 and H3K36me3 deposition in land plants

Monomethylation of histone H3 lysine 4 (H3K4me1) marks enhancers in mammals. However, the function of H3K4me1 in plants remains largely unclear. Here, we analyzed the genome-wide distribution of H3K4me1 in diverse species across evolution, revealing a distinctive H3K4me1 distribution pattern in land plants. To explore the function of H3K4me1 in plants, we identified an H3K4me1-specific reader protein, Early heading date 3 (Ehd3), and solved the structure of Ehd3 in complex with the H3K4me1 peptide, revealing a unique binding module differing from the previously reported PHD finger proteins. We further identified an Ehd3-binding protein, SET domain group 724 (SDG724), and the deletion of either Ehd3 or SDG724 caused similar defects in plant phenotype and changes in transcriptome and epigenome profiles. Both Ehd3 and SDG724 are enriched at chromatin regions marked by H3K4me1 but not H3K4me2 or H3K4me3. Ehd3 activates the H3K36 methyltransferase SDG724, and H3K36me2/me3 are colocalized with H3K4me1 in the genomes of land plants. Collectively, our results reveal that H3K4me1 directs the establishment of H3K36me2 and H3K36me3 in land plants.

molecular biology↗

SCNT: An R Package for Data Analysis and Visualization of Single-Cell and Spatial Transcriptomics

BackgroundThe emergence of single-cell (SC) and spatial transcriptomics (ST) has revolutionized our understanding of gene expression dynamics in complex tissues. However, it also presents challenges for data analysis and visualization, particularly due to the complexity of ST data and the diversity of analysis platforms. The SCNT (Single-Cell, Single-Nucleus, and Spatial Transcriptomics Analysis and Visualization Tools) package was developed to address these challenges by providing an efficient and user-friendly tool for processing, analyzing, and visualizing SC and ST data. ResultsSCNT is an R-based package that integrates widely used tools such as Seurat and ggplot2, enabling seamless conversion between Seurat and H5ad formats. The package supports high-resolution spatial visualization, including customizable gene expression and clustering plots. SCNT also simplifies key data analysis steps, such as quality control, dimensionality reduction, and doublet detection, significantly enhancing workflow efficiency. We tested SCNT on publicly available PBMC dataset, Visum and Visium HD human kidney tissue data, demonstrating its effectiveness. ConclusionsSCNT offers a valuable tool for researchers exploring SC and ST data. Its simplicity, flexibility, and powerful visualization capabilities provide a streamlined workflow for both novice and advanced users. Future developments will focus on expanding support for additional ST platforms and enhancing mult-omics data integration.

bioinformatics↗

Human microglia in brain assembloids display region-specific diversity and respond to hyperexcitable neurons carrying SCN2A mutation

Microglia critically shape neuronal circuit development and function, yet their region-specific properties and roles in distinct circuits of the human brain remain poorly understood. In this study, we generated region-specific brain organoids (cortical, striatal, and midbrain), each integrated with human microglia, to fill this critical gap. Single-cell RNA sequencing uncovered six distinct microglial subtypes exhibiting unique regional signatures, including a subtype highly enriched for the GABAB receptor gene within striatal organoids. To investigate the contributions of microglia to neural circuitry, we created microglia-incorporated midbrain-striatal assembloids, modeling a core circuit node for many neuropsychiatric disorders including autism. Using chemogenetics to activate this midbrain-striatal circuit, we observed increased calcium signaling in microglia involving GABAB receptors. Leveraging this model, we examined microglial responses within neural circuits harboring an SCN2A nonsense (C959X) mutation associated with profound autism. Remarkably, microglia displayed heightened calcium responses to SCN2A mutation-mediated neuronal hyperactivity, and engaged in excessive synaptic pruning. These pathological effects were reversed by pharmacological inhibition of microglial GABAB receptors. Collectively, our findings establish an advanced platform to dissect human neuroimmune interactions in sub-cortical regions, highlighting the important role of microglia in shaping critical circuitry related to neuropsychiatric disorders. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=188 SRC="FIGDIR/small/657874v1_ufig1.gif" ALT="Figure 1"> View larger version (72K): org.highwire.dtl.DTLVardef@125b36eorg.highwire.dtl.DTLVardef@270079org.highwire.dtl.DTLVardef@903525org.highwire.dtl.DTLVardef@19145c4_HPS_FORMAT_FIGEXP M_FIG C_FIG TeaserModeling regional microglial diversity in sub-cortical regions is challenging. We generated human organoid and assembloid models containing microglia that acquire region-specific heterogeneity. Our work shows dynamic responses of microglia when exposed to hyperexcitable midbrain-striatal circuits, providing an exciting platform to study neuroimmune interactions in human brain development and neuropsychiatric disorders, including SCN2A mutation-mediated monogenic autism. HighlightsO_LI* Single-cell RNA sequencing analyses reveal six distinct microglial subtypes that spontaneously attain unique specialization in human cortical, striatal, and midbrain organoids. C_LIO_LI* Microglia facilitate axonal projections across regional organoids, promoting assembloid formation. C_LIO_LI* Microglia respond to hyperexcitable neurons via calcium signaling and exhibit excessive pruning of neuronal synapses. C_LIO_LI* Blocking microglial GABAB receptors normalizes calcium activity and reduces synaptic pruning, suggesting a potential targeting strategy for synaptic deficits. C_LI

neuroscience↗

Autism-associated SCN2A deficiency disrupts cortico-striatal circuitry in human brain assembloids

Profound autism spectrum disorder (ASD) is frequently attributable to single-gene mutations, with SCN2A (voltage-gated sodium channel NaV1.2) protein-truncating variants (PTVs) being one of the most penetrant. Although cortico-striatal circuitry is implicated as a key node in ASD, the impact of SCN2A deficiency on human neural circuits is unknown. Using the human cortico-striatal assembloid model, we show that the autism-causing PTV SCN2A-C959X impairs long-range cortical axonal projections, reduces striatal spine density, and attenuates excitatory cortical-striatal synaptic transmission. Surprisingly, these assembloids carrying the heterozygous SCN2A nonsense mutation exhibited pronounced network hyperexcitability, a human cell-specific phenotype not observed in Scn2a+/- mice, highlighting a human-specific circuit vulnerability. Collectively, our study unveils human circuit-specific dysfunctions of SCN2A deficiency and SCN2A-mediated ASD. HighlightsO_LIAxonal projections facilitate synapse formation and functional connectivity in human brain assembloids. C_LIO_LINaV1.2 is expressed along neuronal axons, extending to soma and dendrites in human brain assembloids. C_LIO_LISCN2A-C959X disrupts axonal projection patterns, impairs excitatory synaptic transmission, reduces spine density, and results in elevated neuronal excitability. C_LI Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=90 SRC="FIGDIR/small/657036v1_ufig1.gif" ALT="Figure 1"> View larger version (27K): org.highwire.dtl.DTLVardef@6d5b1forg.highwire.dtl.DTLVardef@1795ecdorg.highwire.dtl.DTLVardef@13f0d7eorg.highwire.dtl.DTLVardef@8ee059_HPS_FORMAT_FIGEXP M_FIG C_FIG In briefO_ST_ABSSCN2A haploinsufficiency impairs cortico-striatal circuitry.C_ST_ABSSCN2A haploinsufficiency disrupts axon initial segment (AIS) integrity, leading to hyperexcitability (red arrow), reduced axon projections, and impaired synaptic transmission (decreased sEPSCs and altered network firing). These deficits result in dysfunction within the cortico-striatal circuitry.

neuroscience↗

Neural hierarchy for coding articulatory dynamics in speech imagery and production

Mental imagery is a hallmark of human cognition, yet the neural mechanisms underlying these internal states remain poorly understood. Speech imagery--the internal simulation of speech without overt articulation--has been proposed to partially share neural substrates with actual speech articulation. However, the precise feature encoding and spatiotemporal dynamics of this neural architecture remain controversial, constraining the understanding of mental states and the development of reliable speech imagery decoders. Here, we leveraged high-resolution electrocorticography recordings to investigate the shared and modality-specific cortical coding of articulatory kinematic trajectories (AKTs) during speech imagery and articulation. Applying a linear model, we identified robust neural dynamics in frontoparietal cortex that encoded AKTs across both modalities. Shared neural populations across the middle premotor cortex, subcentral gyrus, and postcentral-supramarginal junction exhibited consistent spatiotemporal stability during the integrative articulatory planning. In contrast, modality-specific populations for speech imagery and articulation were somatotopically interleaved along the primary sensorimotor cortex, revealing a hierarchical spatiotemporal organization distinct from shared encoding regions. We further developed a generalized neural network to decode multi-population neural dynamics. The model achieved high syllable prediction accuracy for speech imagery (79% median accuracy), closely matching the performance of speech articulation (81%). This model robustly extrapolated AKT decoding to untrained syllables within each modality while demonstrating cross-modal generalization across shared populations. These findings uncover a somato-cognitive hierarchy linking high-level supramodal planning with modality-specific neural manifestation, revolutionizing an imagery-based brain-computer interface that directly decodes thoughts for synthetic telepathy.

neuroscience↗

CellReasoner: A reasoning-enhanced large language model for cell type annotation

We present CellReasoner, a lightweight, open-source large language model (LLM) tailored for single-cell type annotation. We introduced a compact training strategy that activates the reasoning capabilities of 7B-parameter LLMs using only 380 high-quality chain-of-thought exemplars. CellReasoner directly maps cell-level gene expression profiles to cell type labels, exhibiting robust zero- and few-shot generalization. The model further demonstrates expert-level, marker-by-marker reasoning, enabling structured, interpretable annotations and offering a practical solution for intelligent single-cell analysis.

bioinformatics↗

DeepAden: an explainable machine learning for substrate specificity prediction in nonribosomal peptide synthetases

Microbial non-ribosomal peptides (NRPs) exhibit remarkable structural diversity and serve as valuable sources of lead compounds for clinical drug development. The biosynthesis of NRPs relies on non-ribosomal peptide synthetases (NRPSs), in which adenylation (A) domains play a pivotal role in defining the core structure by selectively recognizing and activating amino acid substrates. Accurately predicting the substrate specificities of A-domains is thus essential for understanding the core structural and biosynthetic logic of NRPs. Here, we present DeepAden, a two-stage deep learning framework. In the first stage, a graph attention network (GAT)-based model localizes 27-residue binding pockets within 6 [A] of bound substrates and convert these into pocket representations. In the second stage, pocket representations are then encoded alongside substrate information using pretrained language models, and aligned using contrastive learning. In addition, we introduce a SHapley Additive exPlanations (SHAP)-guided data augmentation strategy to mitigate class imbalance and improve robustness, particularly for nonproteinogenic substrates. DeepAden achieves competitive performance compared with state-of-the-art tools on a benchmark dataset, and enabled the identification of two Streptomyces NRPS gene clusters through accurate A-domain substrates specificity predictions. DeepAden offers a powerful tool for precise pocket localization and robust substrate prediction, accelerating the discovery and characterization of novel NRP natural products for future work. The DeepAden web server is available at https://deepnp.site/.

bioinformatics↗

On the Curvature and Relaxation of Microtubule Plus-endTips

Microtubules are essential cytoskeletal components with a broad range of functions in which the structure and dynamics of their plus-end tips play critical roles. Existing mechanistic models explain the tips curving dynamics in different ways: the allosteric model suggests that GTP hydrolysis induces conformational changes in tubulin subunits that destabilize the lattice, leading to protofilament curving and depolymerization, while the lattice model posits that GTP hydrolysis directly destabilizes the microtubule lattice. However, the effect of GTP hydrolysis on the curving dynamics of microtubule tips remains incompletely understood. In this study, we employed a multiscale modeling approach, combining all-atom molecular dynamics simulations with Brownian dynamics simulations, to investigate the relaxation of microtubule plus-end tips into curved configurations. Our results show that both GDP- and GTP-bound tips exhibit an outward bending of protofilaments into curved, rams horn-like structures, characterized by a linear relationship between curvature and distance from the plus-end tip. These observations align with experimental cryo-ET images of microtubule plus-end tips in different nucleotide states. Collectively, our findings suggest that the outward bending of protofilaments at the plus-end tip is an intrinsic feature of microtubules, independent of the nucleotide state. SIGNIFICANCEUnderstanding how microtubules change shape is crucial for elucidating key cellular processes such as cell division and shape maintenance, which are fundamental to both physiological function and disease progression. This study supports the concept that the microtubule plus-end tip relaxation does not align with models that couple shape changes to GTP hydrolysis, at least for the topmost tubulin heterodimers. By interfacing bottom-up multiscale modeling -- using the longest reported atomistic molecular dynamics simulations of microtubule tips-- with existing cryo-ET data, it is shown that protofilament bending operates independently of nucleotide hydrolysis and likely depolymerization. These findings highlight the need for a new conceptual framework that separates GTP hydrolysis from microtubule tip flaring.

biophysics↗

CCN1 forms a complex with GPC4 and heparin to fine-tune signaling activities for embryonic cortical neural stem cell maintenance

Radial glial cells (RGCs) are the neural stem cells (NSCs) in the developing brain, capable of self-renewing and generating neurons and glia in order. The developmental behaviors of NSCs are determined by extrinsic factors from the NSC niche, together with intrinsic factors. Here, we show that Cellular Communication Network 1 (CCN1), a secreted matricellular protein, is an autocrine factor derived from RGCs in the embryonic telencephalon. Loss of Ccn1 in RGCs leads to accelerated lineage progression of RGCs, and causes premature cell cycle exit and neuronal differentiation, resulting in a reduction in NSC pool size, and in turn, at the expense of the perinatal gliogenesis. Mechanistically, CCN1 interacts with an RGC-expressed membrane protein GPC4, one of the heparan sulfate proteoglycans (HSPGs), and is required for GPC4 to maintain NSCs through the Sonic Hedgehog (Shh) signaling pathway, depending on the binding of heparin to CCN1. Our work provides a potential mechanism for the dynamic and sophisticated interconnections of niche components that meet the needs of context-dependent maintenance, differentiation, and fate determination of NSCs.

developmental biology↗

Mitochondria-derived dsRNA-induced stress granules promote IRF3-mediated fibrotic responses

Nucleic acid-induced activation of the anti-viral transcription factor interferon regulatory factor 3 (IRF3) promotes transforming growth factor-beta (TGF{beta})-induced fibrotic responses of hepatic stellate cells in vitro. Herein, we identified molecular mechanisms underlying TGF{beta}-induced IRF3 activation. Gene silencing of IRF3 with short interfering RNA (siRNA) in LX2 human hepatic stellate cells decreased TGF{beta}-induced fibrotic responses. An unbiased proteomic analysis of homeostatic IRF3-interacting proteins revealed striking enrichment in cytoplasmic stress granule components, including G3BP stress granule assembly factor 1 (G3BP1), G3BP2, and cell cycle associated protein 1 (CAPRIN1). TGF{beta} induced cytoplasmic accumulation of mitochondria-derived double-stranded RNA (mt-dsRNA) and assembly of IRF3-containing stress granules. Finally, blockade of G3BP1 activity or depletion of mt-dsRNA decreased TGF{beta}-induced fibrotic responses. Collectively, these findings identify a novel TGF{beta}-mt-dsRNA-stress granule axis in hepatic stellate cells that promotes IRF3-mediated fibrotic responses and potentially implicate cytoplasmic stress granules as a global regulator of fibrosis.

cell biology↗

Metabolic modulation of intratumoral cholesterol with gut microbiota for the treatment of colorectal cancer

Excess cholesterol is positively correlated with colorectal cancer (CRC). Current therapeutic strategies for modulating cholesterol levels in CRC are limited and often come with complications. Here, we demonstrated that microbiome shunting of intestinal cholesterol to anticancer metabolites is a safe and applicable therapeutic approach for CRC. By screening major microbial metabolic products of cholesterol, we found that 4-cholesten-3-one (4-C-3) was selectively depleted in fecal samples and tumor tissues of patients with CRC. 4-C-3 exhibits strong antitumor effects on human CRC cell lines, patient-derived organoids, and patient-derived xenograft (PDX) models. Mechanistically, 4-C-3 suppresses CRC tumorigenesis by dually targeting the epidermal growth factor receptor (EGFR) and Kirsten rat sarcoma viral oncogene homologue (KRAS). 4-C-3 directly binds to EGFR, blocking its signal transduction by inhibiting the binding of EGFR ligands. Additionally, 4-C-3 inhibits oncogenic KRAS variants, such as KRASG12D, by suppressing nucleotide exchange activity and effector engagement. By targeting both EGFR and KRAS, 4-C-3 reduces primary resistance to anti-EGFR therapies caused by KRAS mutations in CRC. As a proof-of-concept study, we showed that delivery of 4-C-3 by Oscillibacter ruminantium, a 4-C-3- producing commensal bacterium that is reduced in CRC patients, or a nonpathogenic Escherichia coli strain engineered to specifically convert intestinal cholesterol into 4-C-3, removed intratumoral cholesterol and led to rapid tumor regression in multiple models of CRC. These results suggest that microbial therapies for restoring intestinal cholesterol homeostasis represent a new therapeutic avenue for CRC.

cancer biology↗

Macrophage Migration Inhibitory Factor Suppresses Natural Killer Cell Response and Promotes Hypoimmunogenic Stem Cell Engraftment Following Spinal Cord Injury

Human induced pluripotent stem cells (iPSCs) offer immense potential as a source for cell therapy in spinal cord injury (SCI) and other diseases. The development of hypoimmunogenic, universal cells that could be transplanted to any recipient without requiring a matching donor, could significantly enhance their therapeutic potential and accelerate clinical translation. To create off-the-shelf hypoimmunogenic cells, we used CRISPR-Cas9 to delete B2M (HLA class I) and CIITA (master regulator of HLA class II). Double-knockout (DKO) iPSC-derived neural progenitor cells (NPCs) evaded T cell-mediated immune rejection in vitro and after grafting into the injured spinal cord of athymic rats and humanized mice. However, loss of HLA class I heightened susceptibility to host natural killer (NK) cell attack, limiting graft survival. To counter this negative effect, we engineered DKO NPCs to overexpress macrophage migration inhibitory factor (MIF), an NK cell checkpoint ligand. MIF expression markedly reduced NK cell-mediated cytotoxicity and improved long-term engraftment and integration of NPCs in the animal models for spinal cord injury. These findings demonstrate that MIF overexpression, combined with concurrent B2M and CIITA deletion, generates hiPSC neural derivatives that escape both T- and NK-cell surveillance. This strategy provides a scalable route to universal donor cells for regenerative therapies in SCI and potentially other disorders.

cell biology↗

Saddle Curvature Association of nsP1 Facilitates the Replication Complex Assembly of Chikungunya Virus in Cells

The replication of positive-sense RNA viruses, including the pathogenic SARS-CoV-1 and -2, DENV, and ZIKV, often takes place in curved cellular membrane compartments of tens to hundreds of nanometers in diameter within host cells. The non-structural proteins (nsPs) of viruses are found to critically control the formation and maintenance of such unique nanoscale membrane structures. However, the molecular mechanism underlying the association and assembly of nsPs around curved membranes has remained elusive, due to the technical difficulties of imaging the nanoscale interaction in live cells. In this study, we leveraged vertically aligned nanostructures to define membrane curvatures in live cells and investigated the assembly of viral nsPs on these curved membranes. Using Chikungunya virus as a model system, we found that its nsP1 was preferentially bound to and stabilized around positively curved membrane sites and the preference became more apparent as the radius of curvature decreased to 150 nm or smaller. This preferential accumulation was mainly attributed to the hydrophobic residues on recently identified membrane association loops (MA loops) of each nsP1 monomer. Molecular dynamics simulations further confirmed the improved binding kinetics and stability of nsP1 on positively curved membranes, especially when a 12-mer ring was formed by the nsP1 dodecamer. More interestingly, a saddle curvature association was enabled by the 3D coordination of nsP1 monomers along the dodecamer ring, where the MA loops of individual nsP1 monomers sensed a wide range of the positively curved membrane in the x-z plane while the rigid nsP1 dodecamer ring stabilized the negative curvature in the x-y plane. Its strong coupling to the saddle curvature fulfilled the need to constrain the neck of the membrane spherule for viral replication. Strikingly, productive CHIKV replication exhibited strong enrichment on patterned nanostructure array, proving the effectiveness of membrane curvature-guided assembly of the functional replication complex. Our findings revealed that the cell membrane facilitated the local enrichment of viral nsPs in a curvature- dependent manner. It opens up membrane curvature modulation as a new dimension to dissect the formation and regulation of membrane compartments for viral replication.

biophysics↗

pH-Controlled Regioselective Rapid Ene-type Reaction (RRER) Enables Bioconjugation of Histone Serotonylation

Triazolinedione (TAD) derivatives have been commonly utilized as protection and labeling reagents for indole and phenol moieties via a reversible ene-type reaction. Previous studies showed that the TAD probes could selectively modify tyrosine and tryptophan side-chains within proteins and peptides under distinct pH conditions. Here, we report a pH-controlled regioselective rapid ene-type reaction (RRER) between TAD and 5-hydroxyindole, where the modification occurs on the C4 position rather than the C3 of inactivated indole rings. Employing this unique reaction, we have performed the selective bioconjugation of serotonylation occurring on the fifth amino acid residue, glutamine, of histone H3 (H3Q5), which does not contain any tryptophan in its protein sequence. Finally, RRER was applied to determine the H3Q5 serotonylation levels in cultured cells and tissue samples, which served as a newly developed powerful tool for in vitro and in vivo histone monoaminylation analysis. Overall, our findings in this research expanded the chemical biology toolbox for investigating histone monoaminylation and facilitated the understandings of TAD-mediated ene-type reactions.

biochemistry↗

A biGWAS strategy reveals the genetic architecture of the interaction between wheat and Blumeria graminis f. sp. tritici

BackgroundWheat powdery mildew, caused by Blumeria graminis f. sp. tritici (Bgt) is one of the most significant diseases affecting global wheat production. Breeding for disease resistance (R) genes against Bgt often follows a boom-bust cycles, where cultivars with effective resistance are widely deployed on an expanding area until virulence emerges in the avirulence (Avr) pathogen population. While extensive effort has been devoted to identifying and cloning R genes, Avr genes remain relatively understudied, limiting our understanding of R-Avr interactions. That said, understanding R-Avr interactions is crucial for developing durable resistance strategies. ResultsWe conducted whole genome sequencing on 245 Bgt isolates collected from major wheat-growing regions in China, identifying 120 genetically unique isolates. Each of these unique isolates was inoculated and phenotyped on a diverse panel of wheat germplasm. Through Genome-Wide Association Analysis (GWAS) in both Bgt and wheat, we identified 65 Avr loci and 251 R loci overlapping with nine and eight cloned Avr or R genes, respectively. On average, each isolate carries eight Avr alleles, ranging from one to 17. Little geographical preference for Avr alleles or their combinations was observed, suggesting that disease resistance breeding against this pathogen should be coordinated at the national level. The level of resistance level is positively correlated with the number of R alleles carried by a wheat line, and the average frequency of an R allele is 2% among the wheat panel, indicating the potential for accumulating R alleles in breeding programs. We mapped 212 R-Avr interactions based on joint GWAS using both plant and pathogen genomes and cross-species epistasis, where a network of interactions was formed between wheat and Bgt. These interactions indicate that pyramiding five major R loci has the potential to confer resistance to half of the Avr loci. As a proof of concept, we successfully verified two previously described R-Avr pairs using tobacco experiments. Furthermore, we provided molecular validation evidence for three new Avr genes, including Bgt-50651, BgtE-5826 and BgtE-20009, and two new R-Avr interactions. Among them, Bgt-50651 interacts with Pm1a, Pm2a, and another unidentified R gene located near the Pm6/Pm52 interval. ConclusionOur study provides a framework for understanding the genetic interaction between plants and pathogens. The discovery of novel R/Avr loci and their complex interaction network underscores the need to integrate crop and pathogen genetic background, particularly the R/Avr allele composition, into breeding program design. These findings have significant implications for developing durable resistance strategies in wheat alongside offering valuable insights into the broader dynamics of plant-pathogen interactions.

genomics↗

Structural Heterogeneity of Proteoform-Ligand Complexes in AMP-Activated Protein Kinase Uncovered by Integrated Top-Down Mass Spectrometry

AMP-activated protein kinase (AMPK) is a heterotrimeric complex ({beta}{gamma}) that serves as a master regulator of cellular metabolism, making it a prominent drug target for various diseases. Post-translational modifications (PTMs) and ligand binding significantly affect the activity and function of AMPK. However, the dynamic interplay of PTMs, non-covalent interactions, and higher-order structures of the kinase complex remains poorly understood. Herein, we report the structural heterogeneity of the AMPK complex arising from ligand binding and proteoforms--protein products derived from PTMs, alternative splicing, and genetic variants--using integrated native and denatured top-down mass spectrometry (TDMS). The fully intact AMPK heterotrimeric complex exhibits heterogeneity due to phosphorylation and multiple adenosine monophosphate (AMP) binding states. Native TDMS delineates the subunit composition, AMP binding stoichiometry, and higher-order structure of AMPK complex, whilst denatured TDMS comprehensively characterizes the proteoforms and localizes the phosphorylation site. This is the first study to structurally characterize AMPK proteoform-ligand complexes. Notably, by integrating native TDMS and AlphaFold, we elucidate a flexibly connected regulatory region of AMPK {beta} subunit that has been difficult to visualize with traditional structural biology tools. Our findings uncover previously unresolvable structural features of AMPK, offer new perspectives on protein kinase regulation, and establish a versatile framework for comprehensive characterization of proteoform-ligand complexes.

biochemistry↗

SpatioCell: A Deep Learning Algorithm for High-resolution Single-cell Mapping through Deep Integration of Histology Image and Sequencing Data

Spatial transcriptomics (ST) is a powerful assay to capture gene expression in tissue context. However, due to the limitation of resolution, most existing ST datasets remain at multicellular resolution which hinders comprehensive understanding of the spatial organization. We propose SpatioCell, a computational algorithm to automatically extract both cell type and expression information at single-cell resolution from ST data, through a morpho-transcriptomic spatial reconstruction framework solved via dynamic programming, integrating morphological and transcriptomic information. This framework enables deterministic single-cell spatial reconstruction, assigning cell identities to precise locations rather than inferring spot-level cell-type composition and expression, and further uncovers overlooked microenvironment features while correcting deconvolution errors. Using the ST data from triple negative breast cancer as an example, SpatioCell reveals the significance of the distance between cancer-associated fibroblast (CAF) and tumor or immune cells for disease progression. The establishment of SpatioCell will broaden the biomedical applications of ST and facilitate investigations of single-cell spatial organization.

bioinformatics↗