bioRxiv Science⌕ Search

Biology subjects

Guo, Y.

Publications and source records attributed to Guo, Y..

At least 55 records · Page 3Linked to original sources

Ginsenoside Ro ameliorates diabetic cardiomyopathy by maintaining ciliary homeostasis and enhancing antioxidation

ObjectiveTo investigate and clarify the role of Ginsenoside Ro (GRo) in diabetic cardiomyopathy (DiaCM) and to elucidate the molecular mechanism by which GRo ameliorates DiaCM. Methods[circled1] The construct of type 2 diabetic mouse model. The bought C57BL/6 male mice were housed in a specific pathogen-free (SPF) animal facility and randomly divided into control, STZ (model), STZ + GRo, and control+GRo groups. The STZ (model) and STZ + GRo groups were fed a high-fat and high-glucose diet combined with intraperitoneal injection of streptozotocin (STZ). The control and control + GRo groups were fed a normal diet, while the control + GRo and STZ + GRo groups were treated with GRo via oral gavage. Then, all groups were evaluated for cardiac function and structure by small animal echocardiography and histological staining including hematoxylin and eosin (HE) and Massons trichrome staining to screen and confirm diabetic cardiomyopathy in mice. Finally, immunofluorescence staining of cilia in mouse heart tissue was performed to determine whether GRo inhibits abnormal ciliary growth. [circled2] The construct of cell models. First, the CCK-8 (Cell Counting Kit-8) assay was used to separately evaluate the cytotoxicity of GRo and the combination of TGF-{beta}1 and PA in myocardial fibroblasts and cardiomyocytes. Subsequently, mouse myocardial fibroblast lines (MCFs) were treated with transforming growth factor-beta 1 (TGF-{beta}1), and H9c2 cardiomyocytes were treated with palmitic acid (PA). Both cell types then received the GRo treatment. [circled3] Molecular and cellular testing. Firstly, we measured serum levels of cardiac injury markers (CK-MB, MYO, and TNNI3), glutathione (GSH), and malondialdehyde (MDA). Secondly, we examined the expression of myocardial fibrosis-related genes (Col1a1, etc.), myocardial hypertrophy markers (Nppa, etc.), cilia-specific genes (Pkd1, etc.), and oxidative stress-related genes (Nrf2, etc.) in both animal and cell samples by Western blotting and RT-qPCR. Finally, we used immunofluorescence staining of myocardial fibroblasts to detect cilia length and phalloidin staining of cardiomyocytes to measure their cross-sectional area. [circled4] The correlation mechanism. Firstly, the cilia-specific inhibitory drug HIP-4 was used to disrupt cilia homeostasis by inhibiting cilia growth. Secondly, small activating RNA (saRNA) was used to upregulate the Pkd1 gene to verify whether GRo exerts its anti-fibrotic effects through the inhibition of PC1. Results[circled1] Animal level. A diabetic cardiomyopathy mouse model was successfully established by combining STZ injection with a high-fat and high-glucose diet, and treatment with GRo significantly ameliorated the associated symptoms. [circled2] Cellular level. We successfully established a myocardial fibrosis model by treating myocardial fibroblasts with TGF-{beta}1, and a myocardial hypertrophy model by treating cardiomyocytes with PA. Immunofluorescence staining demonstrated that GRo significantly decreased cilia length in the fibrosis model, while phalloidin staining showed that GRo significantly attenuated the increase in cardiomyocyte cross-sectional area. [circled3] Molecular level. Compared with the model group, GRo treatment significantly reduced serum levels of cardiac injury markers (CK-MB, MYO and TNNI3), glutathione (GSH) and malondialdehyde (MDA). Western blotting and RT-qPCR analyses of both animal and cell samples revealed that GRo markedly alleviated indicators of myocardial fibrosis and hypertrophy, while also suppressing cilia-specific genes and oxidative stress-related genes. Overall, GRo significantly ameliorated the markers associated with myocardial fibrosis and hypertrophy, and inhibited cilia-specific protein expression as well as oxidative stress parameters. [circled4] The correlation mechanism. The cilia-specific drug hedgehog pathway inhibitor 4 (HPI-4) was used to revealed that cilia homeostasis is closely linked to myocardial fibrosis and shortened cilia inhibit the fibrosis progression. Furthermore, upregulation of the Pkd1 gene by small activating RNA demonstrated that PC1 overexpression abrogates the therapeutic effect of GRo. Finally, GRo can alleviate DiaCM.

Molecular Biology↗

Borrelia burgdorferi infection-enhanced Ixodes scapularis serpins S12c5 and S13c5, target MASP1/3 to inhibit MBL-pathway complement activation and promote spirochete survival

Tick serine protease inhibitors (serpins) are critical for tick feeding success and pathogen transmission. We previously demonstrated that two unique serpins, S12c5 and S13c5, are tandemly duplicated on Ixodes scapularis chromosome 5 and are injected into the host at heightened levels during feeding by Borrelia burgdorferi (Bb)-infected nymphs. Here, we characterize the biochemical properties and immunomodulatory functions of these serpins and investigate their roles in promoting Bb transmission. Despite their response to Bb infection, S12c5 and S13c5 share less than 20% overall amino acid identity and differ critically at their reactive center loop (RCL) P1 site, which determines substrate specificity: S13c5 contains a basic arginine residue, while S12c5 contains a polar serine residue. Consistent with these differences, recombinant S13c5 efficiently inhibited innate immune proteases including fXa, plasmin, and trypsin IV (SI: 2.5, 1.9, and 1.0; ka: 8.56 x 103, 3.97 x 10, and 1.08 x 10 M-{superscript 1}s-{superscript 1}, respectively), and consequently delayed plasma clotting via the common pathway, whereas rS12c5 did not inhibit these proteases. However, despite molecular modeling predicting stronger interactions between S13c5 and complement proteases, both serpins inhibited MBL-pathway complement activation by targeting MASP1/3. Deletion of the RCL domain abolished this inhibitory activity, confirming both proteins function as typical inhibitory serpins. Functionally, rS13c5 enhanced Bb colonization in C3H mouse organs. Interestingly, immune response assays revealed a trade-off: S13c5, despite its broader inhibitory activity, was less immunogenic than S12c5. Collectively, these findings establish S12c5 and S13c5 as Bb transmission factors that promote spirochete survival through disruption of host innate immunity.

Molecular Biology↗

CWF19L2 couples pre-mRNA alternative splicing with the maternal-to-zygotic transition to safeguard female fertility

The maternal-to-zygotic transition (MZT) requires precise spatiotemporal execution of pre-mRNA alternative splicing (AS), yet the core splicing machinery driving this developmental reprogramming remains incompletely understood. Here, we identify the CWF19-like protein 2 (CWF19L2) as an indispensable pre-mRNA AS regulator that safeguards against oocyte and early embryo competence defects (OECD). While murine germline-specific depletion of Cwf19l2 spares morphological folliculogenesis, oocyte maturation, or fertilization, it induces complete female sterility characterized by profound developmental arrest at the 2-cell stage. Mechanistically, maternal deficiency of CWF19L2 localized to nuclear speckles disrupts transcription-splicing-translation coupling, collapsing AS homeostasis during maternal reserves and zygotic genome activation. We further demonstrate that CWF19L2 orchestrates the pre-mRNA splicing network through directly binding to target transcripts and indirectly modulating via interacting with the core spliceosomal factor PRPF8. Importantly, exogenous Cwf19l2 mRNA partially rescues the embryonic arrest. Together, our findings establish CWF19L2 as an indispensable AS engine during the MZT, providing a mechanistic foundation for OECD and a novel molecular etiology for female infertility.

Cell Biology↗

STN-DBS frequency-tuned beta subband dynamics are associated with speech tempo in Parkinson's disease

In Parkinsons disease, subthalamic nucleus deep brain stimulation (STN-DBS) frequency modulates narrow beta subbands, with low-frequency stimulation (LFS) selectively attenuating 15-23 Hz power. The negative association between this subband and speech tempo, together with the LFS-related improvement in articulatory rate, suggests that 15-23 Hz subband dynamics may serve as a candidate neural marker associated with speech tempo modulation.

neuroscience↗

Asymmetric introgression and thermal advantage jointly drive climate-mediated lineage turnover in a mixed-ploidy reed

Species distribution forecasts commonly overlook intraspecific genetic variation, missing a potentially important mechanism of ecosystem change: climate-driven range shifts among lineages within a species native range. Here we integrate population genomic analysis of 495 individuals, multi-site common garden experiments, and species distribution modeling based on 837 occurrence records for three major genetic lineages of the foundation grass Phragmites australis in China. The octoploid FEAU lineage (haplotype P) exhibits superior heat tolerance (critical temperature Tcrit and T50) and produces significantly greater total biomass in three of four common gardens compared to the cold-adapted CN lineage (tetraploid, haplotypes O/M), which occupies a climatic niche with lower annual mean temperature (Bio1) and mean temperature of the wettest quarter (Bio8). Genomic analyses further reveal bidirectional but asymmetric introgression, with admixed individuals showing a systematic bias toward FEAU ancestry. Under the high-emission scenario (SSP5-8.5) by 2070, projected highly suitable habitat for the FEAU lineage expands by 18.6%, while the CN lineage shows a smaller relative increase. By contrast, the subtropical SW lineage (haplotypes U/I) exhibits limited and stable suitable habitat. These results demonstrate that climate change interacts with intraspecific variation among polyploidy-associated lineages, manifested through differences in thermal tolerance, biomass production, and asymmetric gene flow, to drive potential lineage replacement within a native range, a process already suggested by field observations of FEAU expansion in a plateau lake. Our findings argue for integrating evolutionary history and genetic identity into ecological forecasting to better anticipate ecosystem responses under ongoing climate warming.

ecology↗

Iterative Spatial Resolution Enhancement in Imaging Mass Spectrometry via Hydrogel Tissue Expansion and Multimodal Image Fusion

The pixel size of imaging mass spectrometry (IMS) is fundamentally limited by several factors, including the diameter of the incident probe and the raster step size of the sample stage. We have previously demonstrated that hydrogel-based tissue expansion, originally developed for microscopy (ExM), can also be adapted for imaging mass spectrometry to physically magnify the size of the tissue. Expansion imaging mass spectrometry (ExIMS) uses a superabsorbent hydrogel to isotropically expand thin tissue sections, which can then be sampled via imaging mass spectrometry, resulting in improved effective spatial resolution. Separately, multimodal image fusion has been used to computationally upsample the effective spatial resolution in imaging mass spectrometry by predictively mapping mass spectrometric intensity values to the smaller diameter pixel sizes of a microscopy image of the same tissue section. Here, we present ExFusion, a unified workflow that combines these two approaches by computationally fusing structurally detailed fluorescent ExM and chemically detailed lipid ExIMS data obtained from the same 9.4-fold expanded mouse brain tissue. Following a 10-fold upsampling from image fusion, multimodal expansion image fusion enabled prediction of MS images at a [~]106 nm pixel size on a commercial mass spectrometer using a 10 m raster step size. At this resolution, lipids in the Purkinje cells of the cerebellum are clearly defined with intracellular distributions.

biochemistry↗

Spatial Gene Set Enrichment Analysis with Applications to Spatially Resolved Transcriptomic Data

Spatially resolved transcriptomics enables the systematic characterization of spatial gene expression variation across tissue sections. Spatially variable genes within the same biological pathway often exhibit similar spatial expression patterns, reflecting shared biological functions and tissue organization. However, existing gene set enrichment analysis methods typically ignore this spatial dependence, which may reduce power to detect spatially organized pathways and limit the interpretability of pathway-level findings. To address this limitation, we propose spaGSE, a Bayesian hierarchical model for spatial pathway enrichment analysis that integrates genelevel summary statistics from spatial expression analysis with predefined gene set annotations. spaGSE models latent spatially variable gene signals through a Gaussian mixture framework and links spatial variation to gene set membership using logistic regression. To support robust and interpretable inference, we impose a spike-and-slab prior on the enrichment coefficient. Through simulation studies and analyses of four public SRT datasets, we show that spaGSE is scalable and achieves higher power while maintaining false positive rate control compared with existing approaches. In real-data applications, spaGSE identifies biologically relevant pathways with coordinated spatial organization across cancer and developmental tissues, demonstrating the value of incorporating spatial information into pathway-level inference for spatial transcriptomics.

bioinformatics↗

SARS-CoV-2 BA.3.2.2 is more evasive of neutralization by sera from young children

Dominant SARS-CoV-2 variants have most prominently displayed greater evasion of serum neutralizing antibodies than predecessor strains. BA.3.2, a descendant of Omicron BA.3, carrying 43 additional spike mutations, emerged in 2024, and over the last several months its subvariant BA.3.2.2 has slowly increased in prevalence globally. BA.3.2.2 continues to circulate at lower frequency than the genetically and antigenically distant dominant JN.1 subvariants NB.1.8.1 and XFG. However, concerningly, epidemiologic analyses have suggested that a larger proportion of COVID-19 cases in children are caused by BA.3.2.2 compared to adults, raising the possibility that susceptibility to BA.3.2.2 differs across age groups. Since immune imprinting shapes variant-specific anti-SARS-CoV-2 antibody profiles and children born after 2021 primarily were first exposed to Omicron subvariants, we hypothesized that young children may have lower circulating neutralizing antibody titers against BA.3.2.2 than adults. Using pseudovirus neutralization assays, we measured titers against BA.3.2.2 and other SARS-CoV-2 variants in serum or plasma samples from a total of 36 adults ([≥]18 years old), school-age children (3-10 years old), and infants/toddlers (6-28 months old) in the US. We found that both cohorts of children had lower geometric mean titers against BA.3.2.2 than adults, even though all tested age groups had similar titers against dominant strains NB.1.8.1 and XFG. Together, these findings suggest that susceptibility to emerging SARS-CoV-2 variants may diverge across age groups, perhaps as a result of their different exposure histories. Furthermore, these results highlight the importance of SARS-CoV-2 surveillance and the monitoring of immunity against viral variants across age ranges.

microbiology↗

Instant Prior-Free Resolution Enhancement for Cross-Modality Microscopy

The resolving power of optical microscopy is fundamentally constrained by the diffraction of light, limiting our ability to visualize subcellular structures. Computational methods, particularly deconvolution, can restore blurred images but critically depend on an accurate point spread function (PSF), whose estimation is often impractical and error-prone, leading to artifacts. Here, we introduce Nonlinear Fourier Re-weighting (NFR), a rapid algorithm that operates without any prior knowledge of the imaging system, achieving deconvolution-like effects through a single logarithmic mapping of the images Fourier spectrum. This non-iterative process re-balances spatial frequency components to computationally reverse the effects of optical blurring. We demonstrate that NFR robustly enhances resolution beyond the Sparrow limit and recovers authentic structural details. NFR excels where traditional methods fail, remaining effective in the presence of severe optical aberrations and high noise. Furthermore, NFR synergistically improves the output of super-resolution modalities like structured illumination microscopy (SIM), and its near-instantaneous processing enables real-time enhancement of dynamic biological processes, such as in vivo multi-photon microscopic imaging deep within scattering tissue. By decoupling high-fidelity image restoration from system modeling, NFR offers a powerful, accessible, and universally applicable tool for improving image quality across diverse microscopic techniques, facilitating the analysis of large datasets and the discovery of previously obscured biological phenomena.

bioengineering↗

A Monoclonal Antibody Panel to Track Ongoing Antigenic Evolution of SARS-CoV-2 Variants

SARS-CoV-2 continues to evolve, generating successive variants with enhanced resistance to antibody-mediated neutralization. However, many existing monoclonal antibody (mAb) repertoires were derived from exposures to ancestral or early Omicron strains and thus incompletely capture the antigenic landscape of newly emerging strains. Here, we generated a mAb panel by immunizing naive, unimprinted VelocImmune humanized mice with spike from the KP.3.1.1 variant, and isolated and characterized 11 neutralizing antibodies targeting diverse epitopes of recently evolved antigenic variants. We then integrated these antibodies with previously characterized mAbs to establish an expanded toolbox for profiling antigenic evolution among emerging variants. Application of this panel to currently emerging SARS-CoV-2 variants provided mechanistic insight into recent antigenic evolution, highlighting the potential role of altered receptor-binding domain conformation. Our data also revealed clear differences in antibody-evasion profiles between JN.1-derived lineages and BA.3.2 lineages. Together, our findings establish an updated mAb panel for monitoring SARS-CoV-2 antigenic evolution.

microbiology↗

Intermediate Relative Humidity Preserves Respiratory Syncytial Virus via a Semi-Solid Bioaerosol State

Respiratory syncytial virus (RSV) transmission via the aerosol route remains poorly understood, particularly with respect to how evolving virus-laden particles (bioaerosols) microenvironments influence viral survival. Bioaerosol particles contain complex mixtures of organic and inorganic components, and their physicochemical properties change dynamically during evaporation as water is lost upon emission from respiratory activities. These changes directly affect the local environment surrounding embedded virus during both the evaporation stage and the subsequent equilibrium state. However, how these microenvironmental conditions under different relative humidity (RH) levels regulate RSV survival remains unclear. In this study, we quantified RSV survival during the evaporation and early equilibrium stages using a flow-tube system with controlled residence times. Bioaerosols were generated from virus medium alone or supplemented with bovine serum albumin (BSA) or mucin and evaluated under low (35%) and intermediate (61%) RH conditions. Viral infectivity was normalized to RNA copy number to account for particle and sampling losses. At 35% RH, RSV infectivity decreased by one to three orders of magnitude, depending on the solution composition. In contrast, survival was significantly higher at intermediate RH, particularly for virus medium and BSA-supplemented aerosols. Scanning electron microscopy revealed that low RH conditions promote efflorescence, whereas intermediate RH results in viscous or semi-solid particles with higher water content. These observations suggest that efflorescence is associated with enhanced RSV inactivation, while viscous or semi-solid phases tend to preserve RSV in the aerosol state for respirable particles. Overall, RSV infectivity depends strongly on particle chemical composition, phase state (effloresced versus semi-solid), and relative humidity. These results highlight the importance of characterizing particle phase behavior and chemical composition during early aerosol processes to improve mechanistic understanding of viral survival relevant to short-range transmission.

microbiology↗

Exercise based Intervention For Metabolic Inflexibility Linked With Lipid Storage Myopathy Using Innovative CRISPR Etf-QO Mutant Knock-in Models

Multiple acyl-CoA dehydrogenase deficiency (MADD) is a rare lipid storage myopathy caused predominantly by pathogenic variants in ETFDH, which encodes ETF-QO in Drosophila, a mitochondrial electron-transfer protein required for fatty acid {beta}-oxidation. Impaired ETF-QO function disrupts electron transfer from multiple acyl-CoA dehydrogenases to the ubiquinone pool, resulting in lipid accumulation, mitochondrial dysfunction, and progressive neuromuscular and cardiac abnormalities. Despite the availability of animal models of fatty acid oxidation disorders, genetically precise in vivo models carrying patient-relevant ETFDH missense variants and permitting longitudinal assessment of disease progression remain limited. Here, we generated CRISPR/Cas9 knock-in Drosophila melanogaster models of late-onset MADD harboring three conserved Etf-QO missense substitutions (L138R, S307C, and L409F), corresponding to human ETFDH mutations L127R, S296C, and L399F, respectively. These variants are located to the conserved FAD- and ubiquinone-binding regions of ETF-QO. Etf-QO mutant flies developed progressive deficits in locomotor activity and skeletal muscle performance accompanied by marked lipid droplet accumulation in indirect flight muscles, cardiac tissue, and fat bodies. Cardiac phenotyping further revealed impaired function, characterized by reduced fractional shortening, prolonged heart period, and increased arrhythmicity index. Consistent with mitochondrial bioenergetic dysfunction, Etf-QO mutants exhibited reduced oxygen consumption, increased oxidative stress, and decreased ATP levels. Molecular analyses indicated activation of cellular energy- and mitochondrial-stress responses, including increased AMPK and PGC-1 signaling, together with elevated Pink1, Parkin, and SOD2 expression, suggesting engagement of mitochondrial quality-control and antioxidant defense pathways in response to ETF-QO dysfunction. Importantly, exercise paradigm consisting of 15 min of daily exercise for 2.5 weeks significantly improved locomotor, skeletal muscle, and cardiac performance while reducing lipid accumulation and reactive oxygen species burden. Together, these findings establish innovative CRISPR knock-in Drosophila models that recapitulate key neuromuscular, metabolic, mitochondrial, and cardiac features of ETFDH-associated MADD. The models reveal coordinated mitochondrial stress and energy-signaling responses to ETF-QO dysfunction and demonstrate that exercise can ameliorate multiple disease phenotypes. These findings provide a tractable in vivo platform for dissecting MADD pathogenesis and evaluating potential therapeutic strategies targeting mitochondrial dysfunction and lipid storage myopathies.

cell biology↗

Genetic canalization of nutrient resorption: evidence from a widespread grass under effective salt stress

Nutrient resorption is a key plant strategy for nutrient conservation, yet whether it responds plastically to non-nutrient stressors such as salinity remains unresolved. Using a common garden experiment with 110 genotypes of the cosmopolitan grass Phragmites australis, we first established that the imposed salinity treatment induced strong multi-level stress responses: above-ground biomass declined by >60%, sodium accumulated 3- to 5-fold across all leaf stages, and 484 metabolites showed significant differential accumulation, including canonical markers of osmotic and oxidative stress. Against this backdrop of confirmed stress, we found that nutrient resorption efficiency (NuRE) remained largely unaffected by salinity. Instead, NuRE was strongly correlated with phylogeographic lineage, ecotype, and latitude of origin, demonstrating evolutionary canalization rather than short-term acclimation. Element-specific regulatory patterns were also evident: while phosphorus resorption followed concentration-dependent control regardless of stress, nitrogen control was disrupted under salinity, and potassium resorption showed no such dependence. Our findings reveal that intraspecific variation in nutrient resorption is predominantly shaped by historical adaptation and geographic context, not by plasticity to salinity. This genetic canalization of a key functional trait implies that predictions of nutrient cycling under global change must account for the phylogeographic composition of plant populations.

ecology↗

A Panel of Human Monoclonal Antibodies for Tracking the Antigenic Evolution of Influenza H5N1 Clade 2.3.4.4b

The ongoing panzootic of clade 2.3.4.4b H5N1 influenza has resulted in widespread infection of birds, mammals, and livestock, underscoring the need for tools to interpret its real-time evolution. Here, we describe the isolation and characterization of a panel of 19 human monoclonal antibodies that potently neutralize current isolates. Competition immunoassays and cryo-electron microscopy analyses revealed their collective near-complete epitope coverage of the H5-hemagglutinin surface. Neutralization profiling across multiple historical and contemporary H5 viruses defined their epitope-specific patterns of virus neutralization. One cluster of antibodies potently neutralized only clade 2.3.4.4b viruses, while many others exhibited broadly neutralizing activity against diverse H5N1 clades. Application of this structurally calibrated antibody panel to recent North American human isolates revealed genotype-specific antigenic divergence between lineages that have spread among cattle (B3.13) and poultry (D1.1). Together, the findings of this study establish a structurally grounded antibody reference panel spanning major vulnerable sites of H5 hemagglutinin and provide a toolbox for interpreting emergent mutations, monitoring ongoing antigenic drift, and anticipating the evolutionary trajectory of circulating H5N1 influenza viruses.

microbiology↗

Somatic-to-germline transmission of horizontally acquired extrachromosomal circular DNA in Brassica graft chimeras

Whether somatically acquired traits can contribute to heritable variation has remained an open question in plant biology for over a century. Here, using graft-induced periclinal chimeras between Brassica juncea and Brassica oleracea, we identified extrachromosomal circular DNA (eccDNA) as mobile genetic elements capable of crossing histological boundaries and entering the germline. We demonstrated that grafting could promote the horizontal transfer of eccDNA between somatic cell layers, enabling its stable maintenance in recipient tissues and permitting transmission through sexual reproduction across multiple generations. We found that transmitted eccDNA is non-randomly distributed across the genome, preferentially originating from gene-dense regions, and enriched for features associated with molecular persistence, such as inverted repeats, hairpin-forming sequences, and autonomously replicating sequence (ARS) consensus motifs. These genetic regions conferred replication competence, as evidenced by autonomous propagation in an ARS-less heterologous yeast system. Sexual progeny carrying graft-acquired eccDNA exhibited reproducible and lineage-dependent alterations in leaf morphology and drought tolerance, accompanied by coordinated transcriptional reprogramming. Notably, a subset of inherited eccDNA remained transcriptionally active in progeny, producing transcripts absent from self-grafted controls. Our findings establish eccDNA as heritable extrachromosomal elements that link graft-mediated somatic genetic transfer with stable germline transmission, thereby expanding the molecular scope of heritable variation in plants and providing a conceptual framework for graft-based trait transmission.

plant biology↗

Talin controls the spatial distribution of vinculin tension in focal adhesions

Cells transmit force between the extracellular matrix and the actin cytoskeleton through integrin adhesion complexes centred on talin and vinculin. Vinculin binds talin through -helical vinculin-binding sites (VBS) that are exposed when talin rod domains unfold under force. Dissecting the significance of this interaction has relied heavily on the A50I mutation in vinculin, which has been widely used as a talin-binding-null mutant. Here we show that although the A50I mutation abolishes binding to the -catenin VBS, it retains nanomolar-affinity binding to multiple talin VBS. We therefore designed an improved mutant, I12K/A50I, that eliminates this residual talin binding. Biochemical assays and single-molecule stretching experiments demonstrate that I12K/A50I VD1 fails to bind talin even when VBS are exposed by force. Using vinculin tension and conformation sensors, we show that talin binding is required for efficient recruitment of vinculin to focal adhesions and for establishing spatial gradients of vinculin tension. However, vinculin can still experience mechanical load in the absence of talin binding. These results demonstrate that A50I is not a talin-binding-null and reveal that, while talin is not required for vinculin loading, it is essential for organising the spatial distribution of mechanical load within adhesion complexes.

cell biology↗

Land-use intensity overrides grazing and precipitation effects on soil microbial communities in a subtropical agroecosystem

Global change drivers are reshaping agroecosystems and their sustained functions worldwide. While soil microorganisms underpin the resilience of these systems, the individual and interactive effects of multiple anthropogenic stressors on microbial community structure and function using large-scale field experiments remain poorly understood. Here, we utilize a full-factorial field experiment in a subtropical agroecosystem to investigate how land-use intensity, cattle grazing intensity, and altered precipitation regimes interact to shape soil microbiomes. Combining microbiome sequencing with network analyses and functional bioinformatics, we evaluated effects of these drivers on prokaryotic and fungal diversity, composition, predicted functional profiles, and community structure. Land-use intensity emerged as the primary driver of microbial responses, explaining 25% and 13% of the total variation in community composition for prokaryotes and fungi, respectively. Compared to intensively managed pastures, semi-natural pastures had significantly different community composition for prokaryotes and fungi and exhibited 22% higher fungal diversity. Semi-natural pastures were enriched with decomposer-associated taxa and metabolic pathways related to energy and lipid metabolism indicating enhanced microbial activity. Surprisingly, intensively managed pastures showed higher network modularity but lower network richness, suggesting a trade-off between community compartmentalization and complexity under intensive land management. Grazing and precipitation manipulations induced core microbiome changes within land-use intensities but had no impact on overall community structure and no significant interactions with land-use. Together, these findings suggest that long-term land-use legacies exert a persistent influence on soil microbial community structure, function, and organization, shaping the context within which other global change drivers operate in subtropical agroecosystems.

ecology↗

ExMODE: A Multi-Omics Repository for Extremophile Adaptation and Bioprospecting

Extreme environments, though hostile to most life forms, host specialized extremophile communities that have redefined biological cognition and emerged as vital biotechnological resources, with their unique adaptive traits and bioactive molecules driving advances in multiple scientific and industrial fields. However, research on extremophiles is hindered by limitations in culture-based methods, fragmented multi-omics data with non-uniform annotation standards across repositories, the lack of cross-extreme comparative research in existing resources, and the singularity of data dimensionality that neglects key structural information, all of which restrict the functional interpretation of extremophile microbes and the exploitation of their bioprospecting potential. To tackle these challenges, we developed ExMODE (https://db.genomics.cn/exmode/), a comprehensive multi-omics database platform dedicated to extremophiles. It centrally integrates multi-omics data from diverse extreme habitats with a standardized annotation framework, resolving data fragmentation and enabling systematic cross-environment comparative analyses to elucidate extremophile adaptive mechanisms. Moreover, ExMODE aggregates multi-dimensional datasets including genes, genomes, secondary metabolite sequences and protein structures, overcoming the constraints of single-dimensional data and significantly improving the efficiency of biotechnological resource discovery from extreme microorganisms.

microbiology↗