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Liu, B.

Publications and source records attributed to Liu, B..

At least 91 records · Page 5Linked to original sources

Inflammatory macrophages drive smooth muscle dedifferentiation via YAP signaling in murine deep vein thrombosis

BackgroundDeep vein thrombosis (DVT) is a common clinical problem characterized by the formation of blood clots in deep veins. The contribution of venous smooth muscle cells (SMCs) to the onset of DVT, particularly the mechanisms driving their phenotypic changes, remains poorly understood. MethodsWe employed a murine stasis model of DVT via inferior vena cava (IVC) ligation in both male and female mice. Single-cell RNA sequencing (scRNA-seq) was used to analyze the cellular and transcriptomic landscape of the vein wall 24 hours post-ligation. To investigate cellular crosstalk, we utilized an in vitro system where primary mouse aortic SMCs were treated with conditioned media from inflammatory (M1-like) bone marrow-derived macrophages (BMDMs). The effects on SMC phenotype and signaling were assessed using bulk RNA-seq, Western blotting, qRT-PCR, and functional assays. ResultsscRNA-seq analysis revealed that DVT induction promotes a rapid inflammatory response characterized by neutrophil influx and a shift in SMCs from a contractile to a synthetic phenotype in both sexes. Infiltrating myeloid cells were identified as a primary source of signaling to SMCs. In vitro, conditioned media from M1-like macrophages was sufficient to suppress SMC contractile gene expression and function. Mechanistically, this effect was linked to the inhibition of the Hippo pathway effector YAP, evidenced by increased YAP phosphorylation (S127/S397) and a subsequent reduction of total YAP protein in SMCs. We identified macrophage-derived IL-1{beta} as a key ligand that mimics these effects. Importantly, pharmacological activation of YAP rescued contractile gene expression in SMCs exposed to the inflammatory macrophage secretome. ConclusionsOur findings demonstrate that SMC dedifferentiation occurs early in DVT, driven by inflammatory macrophage-mediated suppression of YAP signaling. This study uncovers a critical macrophage-SMC crosstalk mechanism in early DVT pathogenesis and highlights YAP as a potential therapeutic target to preserve vein wall integrity and prevent long-term complications.

cell biology↗

Dietary α-Ketoglutarate delays lung adenocarcinoma in females and modulates TBX5-associated transcriptional programs and the immune microenvironment

Lung adenocarcinoma (LUAD) is the most common form of lung cancer and a leading cause of cancer-related mortality, underscoring the need for new chemopreventive strategies. -Ketoglutarate (-KG), a tricarboxylic acid cycle metabolite and dioxygenase cofactor, links cellular metabolism to chromatin regulation. Here, we show that dietary -KG remodels LUAD in a sex-dependent manner. In female mice, -KG reduced tumor area, decreased repressive histone marks (H3K27me3, H3K9me3), and upregulated TBX5 and myogenesis-associated genes. In male mice, -KG-treated male mice exhibited increased tumor area, elevated H3K27me3, and immune remodeling characterized by CD8 T cell expansion and transcriptomic signatures of T cell exhaustion. Analysis of human LUAD revealed that TBX5 expression is enriched in female tumors and associated with improved survival, suggesting it may serve as a marker of favorable outcome. Together, these findings support -KG as an epigenetic modulator with potential chemopreventive activity in lung cancer and highlight the importance of incorporating sex as a biological variable in preclinical studies. SummaryOral -Ketoglutarate (-KG) has a known anti-aging effect and has been suggested to inhibit cancer development. However, the role of -KG in lung cancer is not known. Here, we investigated the effect of oral -KG on the development of lung adenocarcinoma in a KrasG12D-driven murine model. In females, -KG reduced lung tumor growth, accompanied by TBX5 induction, activation of a myogenesis transcriptional program, and loss of repressive histone methylation. In males, -KG increased tumor growth, coinciding with TBX5 repression, suppression of myogenesis programs, and accumulation of repressive histone methylation. -Ketoglutarate also remodeled the tumor immune microenvironment in a sex-dependent manner, with divergent effects on T cell infiltration. HIGHLIGHTSO_LIOral -Ketoglutarate reduces lung adenocarcinoma development in a genetically engineered murine model in a sex-dependent manner C_LIO_LIIn females, -Ketoglutarate reduces repressive histone marks and induces TBX5/myogenesis C_LIO_LIIn males, -Ketoglutarate increases repressive histone marks and suppresses TBX5/myogenesis C_LIO_LI-Ketoglutarate remodels the tumor immune microenvironment with sex-specific effects C_LIO_LITBX5 is enriched in female LUAD patients and predicts improved survival in human datasets C_LI CONTEXT AND SIGNIFICANCELung adenocarcinoma (LUAD) is the most common form of lung cancer and a leading cause of cancer mortality worldwide. Preventive strategies are limited, highlighting the need for safe approaches that can intercept tumor progression. Metabolic cofactors are increasingly recognized as modulators of the cancer epigenome. Among these, -Ketoglutarate (-KG), a central metabolite of the tricarboxylic acid cycle, functions as a cofactor for chromatin-modifying enzymes. Here, we demonstrate that dietary -KG supplementation limits LUAD progression in female mice, reduces repressive histone methylation, and activates TBX5-associated transcriptional programs. These effects are sex dependent, underscoring the importance of biological context in shaping metabolic responses. In human LUAD, TBX5 is enriched in females and predicts improved survival, suggesting that it may serve as a marker of favorable outcome and help guide future studies of -KG. Together, this work identifies -KG as an epigenetically active metabolite with translational promise for lung cancer chemoprevention. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=154 SRC="FIGDIR/small/677388v1_ufig1.gif" ALT="Figure 1"> View larger version (41K): org.highwire.dtl.DTLVardef@1615a31org.highwire.dtl.DTLVardef@68884corg.highwire.dtl.DTLVardef@cc5ed1org.highwire.dtl.DTLVardef@1652c60_HPS_FORMAT_FIGEXP M_FIG C_FIG One-sentence summary-Ketoglutarate remodels lung adenocarcinoma through sex-dependent epigenetic, transcriptional, and immune reprogramming.

cancer biology↗

Repressed expression of nucleoporins and importins impairs plant defense against an infectious noncoding RNA

Plant pathogens threaten global food security and cause substantial annual economic losses. Of particular concern are host jumps, in which pathogens expand their host range to new species, often resulting in sudden and difficult-to-control disease outbreaks. However, the ability to anticipate such events remains limited by an incomplete understanding of pathogen adaptability and the mechanisms governing nonhost resistance. Here, we show that temperature modulates the infectivity and host range of potato spindle tuber viroid (PSTVd), a pathogenic noncoding RNA that severely impacts solanaceous crops such as potato and tomato. Using in vivo single-molecule RNA structure probing, we found that higher temperatures drive PSTVd into a more uniform RNA conformation associated with enhanced infectivity in tomato. Concurrently, elevated temperature suppresses key host defense pathways, including RNA silencing and NPR1-mediated immunity. Notably, these conditions enable PSTVd to overcome nonhost resistance and establish infection in Arabidopsis thaliana. Our findings reveal that elevated temperature promotes PSTVd host expansion through multiple coordinated mechanisms, linking changes in pathogen behavior with increased host susceptibility, and suggest that ongoing climate warming may heighten the risk of viroid host jumps.

plant biology↗

PI-FC: Pre-training Individual-specific Functional Connectome through State-invariant Contrastive Learning

Functional MRI enables non-invasive mapping of brain connectivity, yet its clinical translation remains hindered by uncontrolled state-dependent variability that obscures individual-specific signatures during routine scanning. Here we introduce PI-FC -- a deep learning framework leveraging state-invariant contrastive learning to extract stable individual brain signatures across diverse arousal levels, cognitive states, and temporal scales spanning tens of seconds to hours. PI-FC achieves equivalent phenotypic prediction accuracy using substantially reduced scanning time, and eliminates state-dependent effects varying task demands and brain states. Trained on 36,119 subjects across 8 independent datasets, our model demonstrates superior cross-site generalization and outperforms traditional functional connectome (FC) in predicting neuropsychiatric conditions including schizophrenia, autism, depression, and anxiety. Furthermore, PI-FC enables zero-shot inference of brain age, biological sex, and cognitive ability without site-specific retraining. Overall, PI-FC represents a robust, clinically scalable framework that overcomes fundamental barriers to real-world deployment of precision functional neuroimaging.

neuroscience↗

Sarbecovirus Rc-o319 S-Protein Structures Reveal Highly Specialized Adaptation to Rhinolophus cornutus ACE2

Bat sarbecoviruses often exhibit species-dependent ACE2 specificity. Understanding the determinants of receptor specificity enables better assessment of the cross-species transmission potential of sarbecoviruses. Here, we characterize the S-protein of Rc-o319, a sarbecovirus identified in Japanese Rhinolophus cornutus bats. Featuring an unusual 9-amino-acid deletion within its receptor binding motif (RBM), Rc-o319 S-protein utilizes its cognate R. cornutus ACE2 (bACE2R.cor) but not human ACE2 (hACE2), demonstrating highly restricted receptor specificity. Cryo-EM structures reveal two locked prefusion conformations of the Rc-o319 S-trimer and define a novel type-1b receptor-binding domain (RBD), featuring a distinct beta-loop (BL) within the RBM due to the RBM-deletion. The Rc-o319-RBD:bACE2R.cor complex structure reveals unique interactions mediated by the specialized BL and RBM-loop of Rc-o319-RBD and by a bACE2R.corglycan. Structure-guided mutagenesis demonstrates that changes in BL and RBM-loop within the Rc-o319 S-RBD must occur simultaneously to allow medium-to-high-affinity hACE2 binding. Comparative assays further show that the bACE2R.cor receptor supports only a subset of sarbecoviruses, highlighting its restricted sarbecovirus compatibility. Our findings establish the Rc-o319 S-protein as a structurally and functionally specialized adaptation to R. cornutus ACE2 and identify the structural constraints limiting its cross-species transmission potential. Author SummarySARS-related viruses are widely found in horseshoe bats. Some can bind the human ACE2 receptor with variable affinities, whereas others bind only bat ACE2 receptors. Understanding the basis for this difference is critical for assessing spillover risk. We studied the spike protein of a bat sarbecovirus, Rc-o319, isolated from Japanese Rhinolophus cornutus horseshoe bats. Although Rc-o319 is genetically related to SARS-CoV-2, it is unable to bind the human ACE2 receptor. Structural analyses and functional experiments revealed that the Rc-o319 spike protein possesses a distinct receptor-binding motif (RBM). This RBM features a specialized "beta-loop" that replaces the "large-loop" found in human-infecting sarbecoviruses. The beta-loop enables high-affinity binding to its cognate Rhinolophus cornutus bat ACE2 receptor while simultaneously preventing optimal interaction with human ACE2. We further found that acquisition of high affinity for the human ACE2 receptor would require coordinated changes across multiple regions of the RBM, including changing the beta-loop into a large-loop structure. Together, our findings demonstrate that the Rc-o319 spike protein is highly adapted to its cognate bat ACE2 receptor and faces substantial structural constraints that limit its ability to switch to binding human ACE2.

microbiology↗

Genome-wide selection on transposable elements in maize

While most evolutionary research has focused on single nucleotide polymorphisms (SNPs), transposable elements (TEs) represent a major but understudied source of mutations that can influence organismal fitness. Previous studies on TEs often overlook the mechanisms and rates of transposition, rely on short-read sequencing that limits TE detection, or focus on small genomes such as Arabidopsis or Drosophila. In this study, we leveraged high-quality, long-read genome assemblies from 26 maize inbreds to investigate natural selection on TEs. We developed a novel and interpretable method, {Phi}SFS, which incorporates TE age and improves resolution for detecting selection. Using this approach, we identified key factors influencing selection on TEs: (1) the distance to the nearest gene, (2) the pre-insertion DNA methylation level at the insertion site, and (3) intrinsic TE characteristics, including copy number and expression level. This work represents the first application of long-read genome assemblies to study TE selection in a major crop species with a typical plant genome size. Our {Phi}SFSmethod offers a broadly applicable framework for detecting selection on TEs, and the factors uncovered provide new insights into the evolutionary dynamics and trade-offs between TEs and host genes.

evolutionary biology↗

Geographical variation drives adaptive equilibrium of the P. falciparum sickle-associated mutations

The recent discovery of genetic mutations in Plasmodium falciparum--the most lethal malaria parasite--that enable it to overcome the protective effects of sickle cell trait, raises fundamental questions about the underlying biological and evolutionary interactions. Here we develop a geostatistical model to compare sickle haemoglobin genotype frequencies to the Plasmodium falciparum sickle-associated alleles across global populations, and find a robust association at multiple geographical scales, implying that sickle drives positive selection for these parasite mutations. A model of parasite evolution and an analysis of local haplotype patterns suggest that key features of these mutations - that they are polymorphic in all African populations and are mutually correlated despite lying in different genome regions - are caused by geographical variation in selection pressure, and that the alleles may have been maintained by balancing selection over timescales comparable to the age of the sickle mutation itself. The predicted impact of this host-parasite interaction on disease outcomes varies widely across populations, and functional data are needed to discover the biological mechanisms involved.

genetics↗

Evolutionary Tree in Chemical Space of Natural Products

Natural products (NPs) are key to biological function and adaptation, with their distribution shaped by complex evolutionary and ecological forces. While it may seem reasonable to assume that closely related species produce chemically similar NPs, this assumption has not been systematically tested at a broad taxonomic scale. Here, we evaluate whether evolutionary (taxonomic) proximity correlates with chemical similarity in large-scale data from the Lotus database of NPs. We use five deep learning-based encoders, including Chemformer and SMILES Transformer, to embed NPs into a high-dimensional "chemical space." Our results demonstrate that, for flowering plants (Magnoliopsida) and conifers (Pinopsida), species separated by shorter taxonomic distances tend to produce significantly more similar NPs. Similar trends are observed for Fungi and Metazoa, albeit with some complications, possibly due to horizontal gene transfer, convergent evolution, and/or incomplete coverage in the dataset used for NPs. Our findings suggest that the evolutionary tree can be statistically recovered in a chemical space of NPs, provided that this space is constructed with appropriate deep learning techniques, and provide a new computational framework to investigate the evolutionary dynamics of secondary metabolism. These results can inform drug design strategies, for example by enabling the reconstruction of NPs from poorly studied or extinct species.

bioinformatics↗

Comprehensive analysis of metabolic reprogramming-related gene signaturesmetabolic reprogramming related gene signature for predicting ovarian cancer prognosis, immune landscape, and potential treatment options

Ovarian cancer (OV) is the most lethal gynecologic malignancy. Metabolic reprogramming is a distinctive feature of cancer and is associated with tumorigenesis and progression. It could be a potential therapeutic target for cancer treatments and a biomarker for assessing cancer prognosis. In this study, we identified metabolic reprogramming-related differentially expressed genes (MRRDEGs) in OV through differential gene expression analysis and conducted a comprehensive characterization of these MRRDEGs. Based on the MRRDEGs, we constructed an effective prognostic risk model including five model genes for OV. The risk score was a valid independent prognostic factor that could more accurately predict the survival of OV patients. It could classify OV patients into distinct risk groups with significant differences in survival. We observed significant differences between risk groups in biological pathway activity, immune cell infiltration patterns, and immunotherapy responses. Specifically, the low-risk group demonstrated superior immunotherapy response compared to the high-risk group. These findings significantly advance our understanding of the relationship between metabolic reprogramming and OV pathogenesis, progression, prognosis, and immunotherapy response, laying a foundation for developing novel biomarkers and therapeutic targets in the future and providing an important reference for the formulation of precision medicine strategies.

bioinformatics↗

Cardioprotective effects of AMPK activation in H1N1 influenza virus infection

Cardiac complications are among the most common and severe extrapulmonary manifestations of influenza virus infection, yet they are rarely recapitulated in mouse models without immunodeficiency. We found that influenza virus A/California/04/2009 (H1N1) carrying a mouse-adaptive amino acid substitution in the PB2 protein (E158A) disseminates to the heart in WT C57BL/6 mice, where it induces inflammation, electrical dysfunction, and fibrotic remodeling. Influenza virus-infected heart tissue was significantly altered in mitochondrial metabolism, extracellular matrix, circadian rhythm, and immunity pathways. Particularly striking was activation of gene expression downstream of the mitochondrial biogenesis-promoting AMPK/PGC-1 axis, which occurred late in infection but failed to reverse the repression of mitochondria-associated genes, suggesting an insufficient or delayed compensatory response. Accordingly, we administered AMPK activator 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR) early in infection and observed restoration of mitochondria-associated gene levels, amelioration of cardiac electrical dysfunction and fibrosis, and improvement in survival without overt effects on lung function. Overall, the advent of an immunocompetent model for severe influenza-associated cardiac dysfunction revealed activation of AMPK signaling as a host-targeted metabolic intervention for mitigating virus-induced heart pathologies

microbiology↗

Design of Orthogonal Far-Red, Orange and Green Fluorophore-binding Proteins for Multiplex Imaging

Fluorescent proteins and small molecule dyes have complementary strengths for biological imaging: the former are genetically manipulatable enabling tagging of specific proteins and detection of protein interactions, while the latter have greater photostability and brightness but are difficult to target. To combine these strengths, we used de novo protein design to generate binders to three bright, stable, cell-permeable dyes spanning the visible spectrum: JF657 (far red), JF596 (orange-red) and JF494 (green). For each dye, we obtain nanomolar binders with weak or no binding to the other two dyes; the accuracy of the design approach is confirmed by a crystal structure of one binder which is very close to the design model. Fusion of the JF567, JF596 and JF494 binders to three different targets followed by staining with the three dyes simultaneously enables multiplex imaging. We further expand functionality by incorporating an active site carrying out nucleophilic aromatic substitution to form a covalent linkage with the dye, and developing split versions which reconstitute fluorescence at subcellular locations where both halves are present, enabling both protein-protein interaction detection and chemically induced dimerization with fluorescence reporting. Our designs combine the advantages of fluorescent proteins and small molecule dyes and should be broadly useful for cellular imaging.

biochemistry↗

Production of unreduced microspores in Arabidopsis flowers cultivated in culture medium suggests a role of sucrose in facilitating meiotic cytokinesis

Live-imaging microscopy technology has been increasingly applied for meiosis study in plants, which largely relies on the set up of a healthy ex vivo culture system for inflorescences ensuring that the captured chromosomes dynamics approaches the natural features of meiosis. Here, we report that Arabidopsis thaliana flowers cultivated in a culture medium (CCM) composed of the half-strength Murashige and Skoog basal salt, MES, Myo-inositol, sucrose and agar produce diploid microspores due to occurrence of meiotic restitution. Cytological studies revealed adjacent nuclei distribution and incomplete cytokinesis at late meiosis II in meiocytes within the CCM flowers. Immunolocalization of -tubulin and the microtubule-associated protein MAP65-3 showed that the orientation of spindles at metaphase II and the organization of radial microtubule arrays at the tetrad stage are interfered, which explains the production of meiotically-restituted microspores. Moreover, the CCM flowers showed a gradually impaired expression of Aborted Microspores (AMS), a key transcription factor regulating tapetum development and meiotic cytokinesis. Interestingly, an increased supply of sucrose in culture medium promoted the expression of AMS and partially rescued haploid microspore formation in the CCM flowers. Taken together, this study suggests a role of sucrose in facilitating meiotic cytokinesis and gametophytic ploidy stability in plants. One-sentence summaryArabidopsis flowers cultivated in culture medium produce unreduced microspores due to interfered meiotic cytokinesis, which is partially rescued by increased sucrose supply.

plant biology↗

Single-Cell Profiling Reveals Altered Endometrial Cellular Features Across the Menstrual Cycle in Endometriosis Patients

Endometriosis is a chronic, estrogen-dependent condition affecting over 190 million women globally, characterized by the ectopic presence of endometrial-like tissue that leads to inflammation, pain, and infertility. Despite its prevalence, the pathogenesis of endometriosis remains poorly understood. Here, we present a comprehensive single-cell transcriptomic atlas comprising 228,000 cells derived from 43 eutopic endometrial biopsies from patients with endometriosis, fibroid controls and healthy controls, sampled across the menstrual cycle. This analysis reveals previously uncharacterized subpopulations of endometrial fibroblasts and epithelial cells undergoing epithelial-mesenchymal transition, alongside disrupted immune cell communication networks. Comparative gene expression profiling implicates oxidative stress, aberrant cell migration, and dysregulated apoptosis as central features of the disease state. These findings suggest that endometriosis alters eutopic endometrial homeostasis, with potential consequences for fertility, regeneration, and disease progression. Our dataset provides a valuable resource for biomarker discovery and identifies candidate therapeutic targets aimed at restoring endometrial function and alleviating symptoms in affected individuals.

bioinformatics↗

Myocyte Enhancer Factor 2A Orchestrates Vascular Redox Homeostasis via Direct Transcriptional Activation of SIRT1

Myocyte enhancer factor 2A (MEF2A), a transcription factor implicated in coronary artery disease, remains unexplored in vascular redox regulation. To address this gap and overcome limitations of current antioxidant therapies, we investigated MEF2As role in oxidative defense using human umbilical vein endothelial cells (HUVECs) and murine models. Adenoviral vectors encoding MEF2A-specific shRNA or mRNA were employed to silence or overexpress MEF2A in HUVECs. For in vivo validation, endothelial-targeted MEF2A knockdown was achieved via AAV1-shRNA delivery in mice fed a high-fat diet. Systemic redox status was assessed by measuring reactive oxygen species (ROS), glutathione homeostasis (GSH/GSSG ratio), NADH/NAD+ balance, mitochondrial membrane potential ({Delta}{Psi}m), and 8-hydroxy-2'-deoxyguanosine (8-OHdG). Mechanistic insights were derived from immunofluorescence, qPCR, western blotting, and dual-luciferase reporter assays. MEF2A silencing induced redox imbalance, characterized by elevated ROS, reduced GSH/GSSG ratio, and {Delta}{Psi}m collapse. Conversely, MEF2A overexpression synergized with SIRT1 to restore glutathione pools, maintain NAD+ homeostasis, and suppress ROS under oxidative stress. Chromatin immunoprecipitation confirmed direct MEF2A binding to two cis-elements in the SIRT1 promoter, driving transcriptional activation. In vivo, MEF2A-deficient mice exhibited amplified vascular oxidative damage, including elevated DNA damage marker (8-OHdG) and ROS levels. Downregulation of SIRT1/PGC-1 in MEF2A silenced cells was verified in vivo. Our findings establish MEF2A as a master regulator of endothelial redox defense via the SIRT1-PGC-1 axis, offering a mechanistic foundation for targeting oxidative cardiovascular disorders. This work suggests pharmacological MEF2A activation as a novel strategy for precision antioxidant therapy in vascular medicine.

molecular biology↗

Canonical microRNA loss drives tumor development implicating therapeutic efficacy of enoxacin in angiosarcoma

Angiosarcoma (AS) is a rare and aggressive tumor arising within the endothelium, characterized by a high metastatic rate and poor prognosis. Our prior work established that endothelial loss of Dicer1, a key enzyme in microRNA (miRNA) processing, drives AS formation in mice, indicating a tumor suppressive role for miRNAs in tumorigenesis. Here, we corroborated this hypothesis by generating a novel conditional knockout model targeting Dgcr8, a core component of the microprocessor complex required for pri-miRNA processing. Conditional deletion of Dgcr8 phenocopies Dicer1 loss, resulting in spontaneous AS formation and global loss of mature miRNAs. We further demonstrate that treatment with enoxacin (ENX), a repurposed antibiotic known to enhance miRNA processing, reduces viability, migration, and clonogenicity of AS cells. ENX increases the abundance of tumor-suppressive miRNAs and downregulates oncogenic pathways, including pathways related to cell cycle progression, angiogenesis, and cell migration. These results establish the essential role of miRNA biogenesis in suppressing AS and reveal a pharmacologically targetable vulnerability via ENX-mediated enhancement of miRNA expression in tumors.

cancer biology↗

Staphylococcus aureus exhibits spatiotemporal heterogeneity in Sae activity during kidney abscess development

Virulence factors are required for bacterial pathogens to establish infection, however, their expression can be energetically costly, and must be tightly controlled to avoid fitness costs. Expression can be controlled at specific stages during infection (temporal regulation) or expressed by small subsets of the bacterial population (spatial regulation). There has been a great deal of interest in developing virulence factor-targeting strategies to combat Staphylococcus aureus infection, but the spatiotemporal regulation of the virulence factor master regulatory systems (Agr, Sae) has not been explored during kidney abscess formation. This information is critical for the design of therapeutics targeting these pathways. Here, we utilized a fluorescent transcriptional reporter approach to visualize dynamics in Agr and Sae activity during abscess formation in the mouse kidney. We categorized kidney abscess formation into four stages, then defined spatiotemporal gene expression. Agr signalling appeared inactive in the kidney; consistent with this, agr mutant abscesses fully developed. In contrast, we observed heterogeneous (ON/OFF) activity of Sae at early stages where bacteria were found intracellularly within neutrophils. Sae activity increased as abscesses developed, and heterogeneity in spatial patterning was observed, but patterns varied between abscesses suggesting distinct microenvironments within individual abscesses. Consistent with a requirement for Sae activity during abscess development, the sae mutant did not develop abscesses past early stages. These results have implications for the genes regulated by Agr and Sae, and suggest a requirement for Sae activity during kidney abscess development. ImportanceInfections with Staphylococcus aureus pose a serious public health threat due to high levels of antibiotic resistance and limited efficacy of alternative therapeutics. There has been a great deal of interest in developing novel therapeutics that target virulence factors essential during infection. However, it remains largely unknown if these factors are required at specific stages of the infection, and whether all bacterial cells or a limited subset express them. Here we sought to examine virulence factor expression using fluorescent reporter strains that would indicate activity of two master regulators of virulence in S. aureus, Agr and Sae. While Agr appeared inactive during kidney abscess development, the Sae system exhibited heterogeneity, increased expression at later stages, and was required for abscess progression. These results provide critical information for the development of virulence factor-targeting strategies for kidney abscess treatment.

microbiology↗

Interwoven DNA-MOF crystals for multi-millennial data storage

DNA has emerged as a promising medium for high-density and energy-efficient data storage, providing a promising solution to capacity constraints and energy demands resulting from the exponential growth of data. Long-term stable storage of DNA data in ambient conditions is a critical requirement for its practical application. Whereas strategies have been proposed to protect DNA from environmental degradation, they are often at the expense of data storage density. Here, we propose a strategy via interweaving metal-organic framework (MOF) and DNA to synthesize DNA-MOF crystal (DNA-MOF), a high-density and long-lifespan DNA-based information material. The uniform distribution of DNA molecules within the crystalline frameworks enables a high loading capacity of up to 30 wt%, corresponding to a theoretical information density of 106.6 exabytes/g. The crystal structure of MOF-DNA demonstrates efficient resistance to environmental damage such as heat, ultraviolet radiation, DNase, etc., achieving an estimated archival half-life over 24,000 years at 9.4 {degrees}C. The interwoven DNA-MOF crystals establish a material foundation for the reliable operation of DNA storage systems in open-field deployment and provide a new pathway toward sustainable long-term management of massive data.

biochemistry↗

Agropyron cristatum genome provides a new insight for wheat improvement with wild relatives

Exploring novel genetic variation for target traits is crucial for advancing wheat breeding and genetic improvement. Since 1990, we have been transferring genes from Agropyron cristatum, a promising wild relative genetic resource featuring robust spike morphology and stress tolerance, into common wheat by distant hybridization. To efficiently harness A. cristatum genes, we de novo assembled a 25.62-Gb high-quality genome of an autotetraploid accession Z559 with 28 chromosomes, and uncovered its specific genome features and an extensive repertoire of genes associated with yield and resistance to abiotic and biotic stresses. We systematically characterized A. cristatum genome introgressions by resequencing 431 wheat-A. cristatum derivatives and cloned the gene AcGNS1, which functions in the regulation of grain number per spike in wheat. Subsequently, we developed an optimized genome-selection model for wheat-A. cristatum breeding derivatives, enabling the rapid selection of new potential varieties. These findings demonstrate a genomic breeding strategy for leveraging novel genetic resources of wild relatives and advancing wheat improvement.

genomics↗