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Mo, J.

Publications and source records attributed to Mo, J..

At least 19 recordsLinked to original sources

Scarless regeneration requires post-translational proteolytic regulation via macrophage-derived Legumain

Macrophages express proteolytic factors in response to injury but how proteases are deployed and regulated during regeneration are incompletely defined. Beyond their transcriptomic expression, activity of individual proteases is defined both by their unique substrate specificity and post-translational modifications of their active forms. Here we show a key role for the lysosomal protease Legumain in controlling ECM dynamics and post-translational processing of the regenerative proteome. Injury interface-targeted Ctsla localization and post-translational processing requires Lgmn in macrophages. Extracellular cues from physical remodeling control differentiation state and injury response of ligament resident fibroblasts. Loss of ECM turnover, including localized Fibronectin 1a/b remodeling, impairs dedifferentiation in legumain mutants and leads to fibrotic scarring. Taken together, we demonstrate a role for macrophage-derived lysosomal proteases as specialized tools required to fine-tune proteome composition and function in regeneration.

cell biology↗

HighFold-Lasso: Topology-Guided Prediction of Lasso Peptide Structures Using AlphaFold3

Lasso peptides are a class of ribosomally synthesized and post-translationally modified peptides (RiPPs) characterized by a mechanically interlocked topology, in which the C-terminal tail is threaded through an N-terminal macrolactam ring formed by an isopeptide bond. This unique topology often confers high thermal stability and resistance to proteolytic degradation. However, the isopeptide linkage, threaded topology, and class-specific disulfide connectivity make lasso peptide structures difficult to reconstruct reliably using general-purpose structure prediction models. Here, we developed HighFold-Lasso, which combines custom covalent connectivity with lasso scaffold-guided adaptive low-noise initialization to enable conditional structure generation guided by lasso conformational priors. On a test set of 52 experimentally determined structures, HighFold-Lasso achieved a 100% lasso topology success rate, with a mean RMSD C-alpha of 1.942 Angstrom for the ring-loop region and 2.375 Angstrom for the full peptide. The framework supports modeling of the four classical lasso peptide classes (I-IV) and can represent noncanonical amino acids, providing computational support for structure-function studies and molecular engineering of lasso peptides.

bioinformatics↗

The function of human PIF1 in G quadruplex formation and replication stress response at ALT telomeres

Cancers maintain their telomeres through two telomere maintenance mechanisms: 85-90% of cancers rely on telomerase (TEL+), while 10-15% of cancers adopt the Alternative Lengthening of Telomeres (ALT) pathway. The Break-Induced Replication (BIR) pathway plays a critical role in maintaining telomere length in the ALT+ cells. In both yeast and human, PIF1, a 5' to 3' helicase, is required for the robust activity of BIR. However, the extent of human PIF1 (hPIF1) involvement in the ALT pathway remains unknown. Here we showed that hPIF1 can be recruited to damaged telomeres in ALT+ cells. In addition, we demonstrated that inhibition of hPIF1 induced DNA damage and G quadruplex (G4) accumulation at ALT telomeres, leading to a moderate reduction of the mean telomere length. Most interestingly, we demonstrated that inhibition of hPIF1 also attenuates checkpoint activation, BLM recruitment, single-stranded DNA (ssDNA) formation, DNA damage, and G4s at telomeres in the FANCM deficient ALT+ cells. Finally, we showed that inactivation of hPIF1 affects the viability of both ALT+ and TEL+ cancers, suggesting that hPIF1 is a potential drug target for cancer therapy.

molecular biology↗

Tracing the 'Panda of the Sea': Species-Specific qPCR Assays for eDNA Monitoring of Critically Endangered Bahaba taipingensis in the Pearl River Estuary

Chinese Bahaba (Bahaba taipingensis, Sciaenidae) is a Critically Endangered, Grade I state-protected marine fish in China. Reliable, non-invasive monitoring tools are urgently needed to inform conservation and restocking efforts. We developed and validated three TaqMan probe-based qPCR assays targeting mitochondrial 12S rRNA, ND5, and control region (D-loop) loci for species-specific detection of B. taipingensis. Primer-probe sets were designed from complete mitochondrial genomes and evaluated in silico against GenBank and in vitro against tissue DNA from B. taipingensis and closely related sciaenids, plus positive eDNA samples; sensitivity was quantified using serial dilutions of synthetic target DNA. All three assays showed high specificity and consistent amplification; 12S rRNA assay (Bhb_12S) was selected for field screening based on superior low-copy sensitivity and minimal by-products. We applied the Bhb_12S assay to 414 seawater samples collected from 23 sites in western Hong Kong during 2025 surveys, detecting B. taipingensis eDNA in the September samples (0.71-2.85 copies per L; mean 2.05), with positive detections confirmed by Sanger sequencing. Overall, these validated qPCR assays provide a robust molecular toolkit for non-invasive monitoring of B. taipingensis and will aid conservation planning, restocking evaluation, and long-term biodiversity assessments in the Pearl River Estuary and adjacent coastal waters.

ecology↗

A U1-U3 snRNA-snoRNA interaction couples SF3B1 mutation to chromatin-state rewiring and genome instability

Mutations in spliceosome factors such as SF3B1 are recurrent across human diseases, including myelodysplastic syndromes and leukemia1-4, yet splicing defects alone do not fully explain the widespread chromatin alterations and genome instability in mutant cells5. Here, by comprehensively mapping snRNA-directed RNA-RNA interactions, we identify two previously unrecognized interaction motifs in U1 snRNA beyond canonical 5' splice-site pairing6,7. These motifs enable U1 RNA to i) bind intronic and other chromatin-associated RNA (caRNA) regions outside of splice sites, and ii) base pair specifically with snoRNA. We uncover a U1-U3 snRNA-snoRNA interaction that recruits the H3K36 methyltransferase SETD2 to caRNA, promoting gene-body H3K36me3 and antagonizing H3K27me3 to modulate chromatin accessibility. The snRNA-snoRNA interface is essential for this previously unrecognized layer of chromatin and transcriptional regulation mediated through SETD2. SF3B1 mutation enhances U1-U3 binding and increases the association of the U1-U3 complex with caRNA, driving chromatin-accessibility remolding, R-loop formation, DNA damage, and copy-number abnormalities that promote tumorigenesis. A U1-specific 2'-O-methoxyethyl antisense oligonucleotide that selectively blocks U1-U3 pairing suppresses these genomic abnormalities, reduces leukemic infiltration, and prolongs survival in xenograft and patient-derived models, establishing pathological snRNA-snoRNA rewiring as a critical driver of SF3B1-mutant leukemogenesis.

cell biology↗

MICAFlow: Fast and Robust MRI Preprocessing Bridging Research Neuroimaging and Clinical Practice

MICAFlow is a fully automated MRI preprocessing pipeline designed to translate advanced neuroimaging workflows from research into routine clinical practice. The pipeline emphasizes speed, robustness, and ease of use, focusing on structural and diffusion MRI. Key innovations include a Label-Augmented Modality-Agnostic Registration (LAMAReg) technique driven by deep learning segmentations for reliable cross-modal alignment, integration of state-of-the-art distortion corrections, and adherence to reproducible standards (Snakemake workflow, BIDSApp specifications). We describe the design of MICAFlow and evaluate its performance across heterogeneous datasets. First, accessibility: MICAFlow processes a multimodal MRI exam in minutes with clinically accessible hardware and without requiring GPU access, making it feasible for same-day clinical use. Second, registration accuracy: LAMAReg achieves cutting-edge multi-modal registration accuracy, yielding accurate alignment of diffusion MRI, FLAIR, and intra-subject T1-weighted images while remaining generally robust to common artifacts. Third, data reliability: Using identifiability, we show MICAFlow maintains consistent performance across diverse datasets, including subjects with pathology, and is closely comparable to contemporary pipelines. In sum, MICAFlows combination of machine learning and efficient workflows produces research-grade data quality with clinical-grade speed. This work demonstrates that advanced MRI preprocessing can be done fast and robustly, helping close the gap between research neuroimaging and broad clinical application of quantitative MRI techniques. The source code for MICAFlow is available here: https://github.com/MICA-MNI/micaflow, and for LAMAReg here: https://github.com/MICA-MNI/LAMAReg.

bioinformatics↗

Cyclic Peptides Target CAPON and Modulate Cellular Responses under Alzheimers Disease-Relevant Stress

CAPON (NOS1AP) is an adaptor protein involved in neuronal nitric oxide synthase (nNOS) signaling and has been implicated in Alzheimers disease (AD), excitotoxicity, and tau-associated neurodegeneration. Here, we report the identification of cyclic peptide ligands targeting CAPON using phage display screening of a disulfide-constrained peptide library. Phage enrichment, ELISA validation, microscale thermophoresis (MST), and biolayer interferometry (BLI) identified CAP1 as the lead peptide, exhibiting low micromolar binding affinity toward CAPON. Computational studies further supported stable CAPON-CAP1 interactions through complementary hydrophobic and electrostatic contacts. Functionally, CAP1 attenuated A{beta}42-induced neuronal toxicity, suppressed NMDA-driven nitric oxide production, and reduced pathological tau phosphorylation in neuronal models under AD-relevant stress conditions. In addition, CAP1 demonstrated favorable preliminary pharmacokinetic properties, including good aqueous solubility, plasma stability, and measurable membrane permeability. Collectively, these findings establish the first cyclic peptide ligands targeting CAPON and identify CAP1 as a promising scaffold for modulation of CAPON-dependent neurodegenerative signaling.

pharmacology and toxicology↗

Integrated analysis of leukemic mutations and transcriptomes at the single-cell level

Single-cell RNA-sequencing-based characterization of cells that belong to the neoplastic clone is a major challenge in hematologic neoplasms, where malignant and normal cells coexist. Confident molecular profiling requires simultaneous analysis of gene expression and genetic mutations in individual cells, an ability that is not supported by the standard 10X Genomics workflow. Here, we systematically evaluated the potential and limitations of repurposing amplified cDNA generated during the 10X Genomics 3' workflow for post-hoc genotyping of individual cells. We first established a mixed leukemic cell line system comprising one cell line with KIT point mutations and another with the BCR::ABL1 fusion gene. Targeted long-read PacBio sequencing enabled post-hoc assignment of mutation data to transcriptionally profiled cells, but recovery differed between targets. Consistent with ambient RNA in microfluidics-based single-cell workflows, mutation-associated transcripts were detected in cells not expected to carry the corresponding mutations, illustrating how transcript recovery complicates cell-level genotype assignment. Target-specific thresholds mitigated this source of misclassification. In primary chronic myeloid leukemia samples, the post-hoc approach detected BCR::ABL1-positive cells at diagnosis, but not during imatinib treatment. Together, we present a framework for adding mutation status to cells already profiled using the 10X Genomics workflow and highlight broader considerations for transcript-based single-cell genotyping.

cancer biology↗

Multidimensional Mechanistic Study of Panax Notoginseng Saponins in the Treatment of Alcohol-Induced Osteonecrosis of the Femoral Head: Integrating Network Pharmacology, Molecular Dynamics Simulation and In Vivo Validation

BackgroundAlcohol-induced osteonecrosis of the femoral head (AIONFH) is an orthopedic disorder from chronic alcohol abuse, characterized by disrupted femoral head blood supply, osteocyte death and structural collapse. Current hip-preserving therapy is unsatisfactory, and most patients eventually require total hip arthroplasty. Panax Notoginseng Saponins (PNS), the core active component of Panax notoginseng, exerts pro-angiogenic and anti-osteocyte apoptosis effects, but its specific therapeutic mechanism remains unclear. ObjectiveThis study used network pharmacology, molecular dynamics simulation and animal experiments to identify PNSs active components, core targets and key pathways for AIONFH, verify its in vivo efficacy, and provide a scientific basis for clinical application. MethodsPNS active components, their targets and AIONFH-related targets were screened from databases; intersection targets constructed an interaction network, core targets were screened by three machine learning algorithms, with concurrent GO and KEGG analysis. Molecular docking was performed between core targets and PNS components; Gromacs 2022 conducted 100 ns simulation to evaluate complex stability. AIONFH rat models were grouped with 4-week intragastric intervention; pathology, immunofluorescence and PCR were used for detection. Results and DiscussionNetwork pharmacology identified 127 PNS targets and 18 intersections with 672 AIONFH targets. Six core targets (including FGF2, HSD11B1) were screened; KEGG indicated VEGF pathway as key. Ginsenoside Re bound HSD11B1 with the lowest binding energy (-12.4 kcal/mol), and 100 ns simulation confirmed complex stability. Animal experiments showed PNS improved trabecular structure and regulated osteocyte activity. PNS treats AIONFH via multi-component, multi-target mode, core mechanism being osteocyte apoptosis inhibition. Results and DiscussionNetwork pharmacology screening identified 127 potential targets of PNS, and 18 potential intersection targets were obtained by overlapping with 672 AIONFH-related targets. Six core targets including FGF2 and HSD11B1 were screened out by machine learning, and KEGG analysis indicated that the VEGF pathway and other pathways were the key signaling pathways for PNS action. Molecular docking showed that Ginsenoside Re had the lowest binding energy with HSD11B1 (-12.4 kcal/mol), and 100 ns molecular dynamics simulation confirmed the stable conformation of this complex. Animal experiments demonstrated that PNS could improve trabecular bone structure and regulate osteocyte activity. In summary, PNS exerts a therapeutic effect on AIONFH through a multi-component, multi-target and multi-pathway mode, with the core mechanism of inhibiting osteocyte apoptosis.

pharmacology and toxicology↗

Precision mapping and molecular contextualization of surgical outcome epicenters in temporal lobe epilepsy

AO_SCPLOWBSTRACTC_SCPLOWTemporal lobe epilepsy is the most common drug-resistant epilepsy, with surgical resection offering the primary path to seizure freedom. Despite standardized approaches, a substantial proportion of patients experience seizure recurrence, and the neurobiological substrates underlying these divergent outcomes remain unclear. We applied an individualized normative modeling framework to multimodal preoperative MRI data in a group that subsequently underwent surgical resection, to characterize patient-specific structural deviations and identify disease epicenters. Patients who became seizure-free exhibited spatially coherent abnormalities localized to the hippocampus and ipsilateral association regions, anchored in agranular limbic territories and enriched for genes linked to calcium-dependent signaling. Non-seizure-free patients, on the other hand, showed a more heterogeneous and distributed pattern of deviations, consistent with a "temporal-plus" network organization, and broader neuromodulatory dysregulation. Crucially, overlap between resected tissue and network-defined epicenters was closely associated with seizure freedom, independent of total resection volume. These findings provide a multiscale framework for precision surgical planning, shifting the focus from standardized tissue removal to targeted disconnection of patient-specific pathological hubs.

neuroscience↗

Carbon dioxide sequestration into biomineral armor by ants

Over geologic time, Earths climate has been shaped by the capture and conversion of atmospheric carbon dioxide (CO2) into stable carbonate minerals, including dolomite [CaMg(CO3)2]. Accelerating natural carbon mineralization offers significant potential for mitigating anthropogenic climate change. Using stable carbon isotope tracking, nano-scale secondary ion mass spectroscopy, and 13C SSNMR, we show that, paralleling global biosphere-level processes, Sericomyrmex amabilis fungus-farming ants rapidly convert CO2 in their nest chambers into a biomineral layer covering their exoskeletons. We further reveal that biogenic carbon mineralization by these ants produces partially ordered dolomite. This rapid sequestration of CO2 into defensive armor in ants provides a fascinating natural example of mediation of potentially toxic accumulation of atmospheric CO2 that could inform human efforts to mitigate climate change.

ecology↗

Streptavidins play a multifunctional role within a biotin-pathway antibiotic network encoded in a biosynthetic supercluster

Streptavidin, the well-known biotin-binding protein extensively used in biotechnology, is naturally co-produced in Streptomyces avidinii alongside stravidins--inhibitors of biotin biosynthesis. Here, we uncover and activate a conserved genomic region flanked by two streptavidin genes, revealing multiple biosynthetic gene clusters that produce diverse biotin-related metabolites, including stravidins, acidomycin, -methyl-KAPA, -methyldesthiobiotin, and the novel non-proteinogenic amino acid ANDA. We show -methyldesthiobiotin arises from -methyl-KAPA, illustrating how methylated analogues interfere with distinct steps of biotin biosynthesis. Contrary to the view that streptavidin functions solely by sequestering biotin, our biochemical, structural, and bioactivity analyses demonstrate that it also binds acidomycin, neutralizing its antibacterial activity to protect the producer while likely facilitating compound secretion. The crystal structure of the streptavidin-acidomycin complex reveals the molecular basis for this dual functionality. Our findings establish a multifunctional streptavidin that integrates biotin sequestration and self-resistance to balance an antibiotic network targeting the biotin pathway in microbial competition.

microbiology↗

SARS-CoV-2 NSP14 inhibitor exhibits potent antiviral activity and reverses NSP14-driven host modulation

The emergence of SARS-CoV-2 variants and drug-resistant mutants highlights the urgent need for novel antiviral therapeutics. SARS-CoV-2 NSP14, an N7-guanosine methyltransferase, plays a critical role in viral RNA capping, enabling viral replication and immune evasion. While NSP14 has emerged as a promising drug target, its role in host-virus crosstalk and the cellular consequences of NSP14 inhibition remain poorly understood. Here, we present the identification and characterization of C10, a highly potent and selective first-in-class non-nucleoside inhibitor of the NSP14 S-adenosylmethionine (SAM)-binding pocket. C10 demonstrates robust antiviral activity against SARS-CoV-2, including its variants, with EC50 values ranging from 64.03 to 301.9 nM, comparable to the FDA-approved drug remdesivir in our cell-based assays. C10 also exhibits broad-spectrum activity against other betacoronaviruses and inhibits SARS-CoV-2 at the replication stage. C10 suppresses viral translation and exhibits immunostimulatory effect. Additionally, C10 specifically reversed NSP14-mediated alterations in host transcriptome. The antiviral efficacy of C10 was further validated in a transgenic mouse model of SARS-CoV-2 infection. Our findings highlight C10 as a promising candidate for the development of effective treatments against SARS-CoV-2 and its emerging variants. This study also uncovers a novel mechanism of NSP14 in SARS-CoV-2 pathogenesis and its therapeutic potential, providing insights that may extend to other viral capping methyltransferases.

microbiology↗

Angptl5 restricts primitive hematopoiesis by modulating retinoic acid signaling in zebrafish

Homeostasis is essential for hematopoiesis, and its dysregulation can lead to severe pathological conditions. Retinoic acid (RA) is a key regulator that exerts concentration-dependent effects on both embryonic and adult hematopoiesis. However, the mechanisms that modulate RA signaling in hematopoietic processes remain poorly understood. Using zebrafish as a model, we identified angiopoietin-like protein 5 (Angptl5) as a critical regulator of hematopoietic homeostasis. Loss of Angptl5 function resulted in myeloid hyperplasia in the anterior lateral plate mesoderm (ALPM) and anterior expansion of erythroid progenitors in the posterior lateral plate mesoderm (PLPM)-- phenotypes consistent with attenuated RA signaling. Molecular analyses confirmed impaired RA signaling in angptl5{Delta}10/{Delta}10 mutants, and exogenous RA supplementation fully rescued the hematopoietic defects. Mechanistically, we found that Angptl5 transcriptionally activates retinol dehydrogenase dhrs9 through its interaction with Integrin 6l{beta}5. Our findings establish Angptl5 as a novel and essential regulator of embryonic hematopoiesis and reveal a previously unrecognized mechanism controlling hematopoietic homeostasis. These insights position Angptl5 as a potential therapeutic target for hematological disorders.

developmental biology↗

Weighted sliced inverse regression for scalable supervised dimensionality reduction of spatial transcriptomics data

With the dramatic take-up of spatially resolved transcriptomics biotechnologies, performing spatially-aware analysis of the resulting data is crucial to maximise advances in biological understanding. Dimensionality reduction is a first step in almost any analysis of spatial transcriptomics data, regardless of whether the data is collected at the single-cell or spot level. While common approaches, such as principal component analysis, aim to identify low-dimensional scores that preserve total variances of gene expression features, such variances do not usually correspond to biologically relevant spatial variation. To this end, we have developed weighted sliced inverse regression (wSIR), a sufficient dimension reduction technique that performs dimensionality reduction and retains as much predictive power of the spatial coordinates as possible. As a linear dimensionality reduction approach, wSIR is applicable to multiple distinct spatial transcriptomic datasets, and is extremely scalable due to the algorithm and our Rcpp implementation, with over 100, 000 cells processed in under 2 minutes on a standard laptop. The feature loadings are interpretable, and new non-spatial data can be projected into the wSIR low-dimensional space for further downstream analyses. We examine wSIRs performance through benchmarking and demonstrate its capability of biological discovery through two case studies in breast cancer and early embryonic development.

genomics↗

Passage of human-origin influenza A virus in swine tracheal epithelial cells selects for adaptive mutations in the hemagglutinin gene

AbstractFrequent spillover of influenza A viruses from humans to swine contributes to the increasing diversity of influenza viruses circulating in pigs. Although these events are common, little is known about the adaptation processes that take place when viruses jump between the two species. We examined the changes that occurred during serial passages of a reassortant H3N2 virus (VIC11pTRIG) containing human seasonal surface genes (Hemagglutinin and Neuraminidase) and a swine-adapted internal gene constellation in differentiated primary swine tracheal epithelial cells (pSTECs). The VIC11pTRIG reassortant virus was serially passaged 8 times in pSTECs and compared to a control swine-adapted strain (OH/04p) containing the same internal gene constellation. Viral RNA from passages 0 (inoculum), 1, 3, 4-8 were sequenced via next generation or Sanger sequencing. Hemagglutinin diversity was highest at passage 3. Two amino acid mutations in the Hemagglutinin protein (N165K and N216K) were fixed at passages 7 and 5, respectively. These changes were associated with increased fitness of the virus in pSTECs compared to the original parental strain. Our results suggest that the adaptation of human seasonal H3N2 to swine cells may lead to the selection of HA mutations located near the receptor binding site. These mutations may result in increased fitness of human-origin H3N2 strains to adapt in swine.

microbiology↗

Single-cell omics-based characterization of human basophils reveals two transcriptionally distinct populations

BackgroundBasophils are implicated in various diseases including allergies, but a comprehensive characterization of human basophils has yet to be performed at the single-cell level. ObjectiveWe aimed to generate a single-cell omics-based resource of circulating human basophils, to be made accessible to the research community. We also sought to investigate basophil heterogeneity at the transcriptional and surface epitope levels. MethodsCirculating basophils were analyzed using short- and long-read single-cell RNA-sequencing in combination with large-scale immunoprofiling of more than 100 cell surface markers. ResultsWe used a cellular indexing of transcriptomes and epitopes by sequencing (CITE-seq) based cell barcoding system to accurately track side scatterlow lineage- CCR3+ Fc{varepsilon}RI+ basophils through the single-cell omics analysis. The approach allowed for accurate transcriptional profiling of basophils among low-density peripheral blood leukocytes. The generation of an additional dataset with only basophils revealed two transcriptionally distinct populations. Single-cell transcriptomic analysis of samples from additional donors was performed and coupled with a large-scale immunoprofiling screen, producing a third CITE-seq dataset containing basophils. The analysis verified the existence of the two transcriptionally distinct populations and revealed that these populations have similar immunophenotypes with regard to the investigated surface markers. Long-read single-cell RNA-sequencing analysis provided further insights into the gene expression dynamics of the circulating basophils and confirmed the transcriptionally defined basophil states. ConclusionsThe single-cell omics analysis revealed two transcriptionally distinct basophil populations. Our single-cell omics resource constitutes a reference for charting human basophils at the cellular and molecular levels in health and disease. Capsule summaryShort- and long-read single-cell RNA-sequencing coupled with large-scale immunoprofiling characterize human basophils in peripheral blood and reveal two transcriptionally distinct populations.

immunology↗

Dynamic cell fate plasticity and tissue integration drive functional synovial joint regeneration

Adult mammalian synovial joints have limited regenerative capacity, where injuries heal with mechanically inferior fibrotic tissues. Here we developed a unilateral whole-joint resection model in adult zebrafish to advance our understanding of how to stimulate regrowth of native synovial joint tissues. Using a combination of microCT, histological, live imaging, and single-cell RNA sequencing (scRNAseq) approaches after complete removal of all joint tissues, we find de novo regeneration of articular cartilage, ligament, and synovium into a functional joint. Clonal lineage tracing and scRNAseq implicate a multipotent, neural crest-derived population in the adult skeleton as a cell source for these regenerating tissues. Together, our findings reveal latent molecular and cellular programs within the adult skeleton that are deployed to regenerate a complex joint with lubricated articular cartilage.

developmental biology↗