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Biology subjects

Zhou, Q.

Publications and source records attributed to Zhou, Q..

At least 127 records · Page 7Linked to original sources

Pathway-enhanced Transformer-based model for robust enumeration of cell types from the cell-free transcriptome

Analyzing cell types of origin of cell-free RNA can enhance the resolution of liquid biopsies, thereby deepening the understanding of molecular and cellular changes in development and disease processes. Existing deconvolution methods typically rely on meticulously curated gene expression profiles or employ deep neural network with vast and complex solution spaces that are difficult to interpret. These approaches overlook the synergistic and co-expression effects among genes in biological signaling pathways, compromising their generalizability and robustness. we developed Deconformer, a Transformer-based deconvolution model that integrates biological signaling pathways at the embedding stage, to address these issues. Compared to popular methods on multiple datasets, Deconformer demonstrates superior performance and robustness, and is capable of tracking the developmental process of the fetal and placenta. Additionally, pathway-level interpretability of Deconformer offers new insights into crosstalk, dependencies, and other interactions within cell-free RNA pathways, supporting further biological discoveries. We posit that Deconformer represents a significant advancement in the precise analysis of the cell-free transcriptome. It holds the promise of describing disease progression and severity with a new level of accuracy, focusing on the contributions of originating cell types and their pathway dependencies. This model has the potential to catalyze the development of non-invasive diagnostic tools and enhance our understanding of the underlying biology of diseases.

bioinformatics↗

Cell circuits underlying nanomaterial specific respiratory toxicology

Nanomaterials emerged as boundless resource of innovation, but their shape and biopersistence related to respiratory toxicology raise longstanding concerns. The development of predictive safety tests for inhaled nanomaterials, however, is hampered by limited understanding of cell type-specific responses. To advance this knowledge, we used single-cell RNA-sequencing to longitudinally analyze cellular perturbations in mice, caused by three carbonaceous nanomaterials of different shape and toxicity upon pulmonary delivery. Focusing on nanomaterial-specific dynamics of lung inflammation, we found persistent depletion of alveolar macrophages by fiber-shaped nanotubes. While only little involvement was observed for alveolar macrophages during the initiation phase, they emerged, together with infiltrating monocyte-derived macrophages, as decisive factors in shifting inflammation towards resolution for spherical nanomaterials, or chronic inflammation for fibers. Fibroblasts, central for fibrosis, sensed macrophage and epithelial signals and emerged as orchestrators of nanomaterial-induced inflammation. Thus, the mode of actions identified in this study will significantly inspire the precision of future in vitro testing. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=80 SRC="FIGDIR/small/579746v1_ufig1.gif" ALT="Figure 1"> View larger version (31K): org.highwire.dtl.DTLVardef@1d6f061org.highwire.dtl.DTLVardef@3fabb1org.highwire.dtl.DTLVardef@21040eorg.highwire.dtl.DTLVardef@1915c3b_HPS_FORMAT_FIGEXP M_FIG C_FIG

pharmacology and toxicology↗

Pia-FLOW: Deciphering hemodynamic maps of the pial vascular connectome and its response to arterial occlusion

The pial vasculature is the sole source of blood supply to the neocortex. The brain is contained within the skull, a vascularized bone marrow with a unique anatomical connection to the brain. Recent developments in tissue clearing have enabled unprecedented mapping of the entire pial and calvarial vasculature. However, what are the absolute flow rates values of those vascular networks? This information cannot accurately be retrieved with the commonly used bioimaging methods. Here, we introduce Pia-FLOW, a new approach based on large-scale fluo-rescence localization microscopy, to attain hemodynamic imaging of the whole murine pial and calvarial vasculature at frame rates up to 1000 Hz and spatial resolution reaching 5.4 {micro}m. Using Pia-FLOW, we provide detailed maps of flow velocity, direction and vascular diameters which can serve as ground-truth data for further studies, advancing our understanding of brain fluid dynamics. Furthermore, Pia-FLOW revealed that the pial vascular network functions as one unit for robust allocation of blood after stroke.

neuroscience↗

Transcriptomic interplay between Acinetobacter baumannii, human macrophage and polymyxin

Optimization of antibiotic therapy has been hindered by our dearth of understanding on the mechanism of the host-pathogen-drug interactions. Here, we employed dual RNA-sequencing to examine transcriptomic perturbations in response to polymyxin B in a co-culture infection model of Acinetobacter baumannii and human macrophages. Our findings revealed that polymyxin B treatment induced significant transcriptomic response in macrophage-interacting A. baumannii, exacerbating bacterial oxidative stress, disrupting metal homeostasis, affecting osmoadaptation, triggering stringent stress response, and influencing pathogenic factors. Moreover, infected macrophages adapt heme catabolism, coagulation cascade, and hypoxia-inducible signaling to confront bacterial invasion. Disrupting rcnB, ompW, and traR/dksA genes in A. baumannii impairs metal homeostasis, osmotic stress defense and stringent responses, thereby enhancing antibacterial killing by polymyxin. These findings shed light on the global stress adaptations at the network level during host-pathogen-drug interactions, revealing promising therapeutic targets for further investigation. IMPORTANCEIn the context of the development of bacterial resistance during the course of antibiotic therapy, the role of macrophages in shaping bacterial response to antibiotic killing remains enigmatic. Herein we employed dual RNA-sequencing and an in vitro tripartite model to delve into the unexplored transcriptional networks of the Acinetobacter baumannii-macrophage-polymyxin axis. Our findings uncovered the potential synergy between macrophages and polymyxin B which appear to act in co-operation to disrupt multiple stress tolerance mechanisms in A. baumannii. Notably, we discovered the critical roles of bacterial nickel/cobalt homeostasis (rcnB family), osmotic stress defense (ompW family), and stringent response regulator (traR/dksA C4-type zinc finger) in tolerating the last-line antibiotic polymyxin B. Our findings may lead to potential targets for the development of novel therapeutics against the problematic pathogen A. baumannii.

microbiology↗

Gating of Memory to Behavior by the Locus Coeruleus

An essential function of memory is to guide behavior for survival and adaptation. While considerable knowledge has been accumulated on memory formation, much less is understood about how retrieved memories direct behavior/action. In the auditory Pavolovian threat conditioning paradigm, retrieval of conditioned threat memory activates dorsomedial prefrontal (dmPFC) neurons exhibiting transient responses (T-neurons), which activate both dmPFC neurons exhibiting sustained responses (S-neurons) and locus coeruleus (LC) neurons. Auditory inputs to S-neurons enable the conversion from transient to sustained responses so that the freezing durations match those of the auditory cues. Activation of LC neurons is required for the conversion by enhancing S-neuron responses, which, interestingly, opens a short time window during which non-conditioned cues also lead to freezing. The transition from memory to behavior thus hinges on the integration of retrieved memory, sensory inputs, and emotional/body state cues to generate a selective, adequate, and finely tuned behavior. Significance statementThis study provides new insights into the neural circuitry and mechanisms of how retrieved memories direct the execution of behavior in response to conditioned threatening stimuli. It reveals how different neuron types in the dmPFC interact with LC neurons to determine and modulate the duration and intensity of defensive responses. It also shows that activation of LC neurons can induce the generalization of freezing to non-threatening cues, which may have implications for understanding anxiety disorders. This study contributes to the field of neuroscience by advancing the understanding of memory-behavior conversion and role of the dmPFC and LC in conditioned threat/fear behavior.

neuroscience↗

Transcription factor dynamics, oscillation, and functions in human enteroendocrine cell differentiation

Enteroendocrine cells (EECs), which secrete serotonin (enterochromaffin cells, EC) or a dominant peptide hormone, serve vital physiologic functions. As with any adult human lineage, the basis for terminal cell diversity remains obscure. We replicated human EEC differentiation in vitro, mapped transcriptional and chromatin dynamics that culminate in discrete cell types, and studied abundant EEC precursors expressing selected transcription factors (TFs) and gene programs. Before expressing the pre-terminal factor NEUROD1, non-replicating precursors oscillated between epigenetically similar but transcriptionally distinct ASCL1+ and HES6hi cell states. Loss of either factor substantially accelerated EEC differentiation and disrupted EEC individuality; ASCL1 or NEUROD1 deficiency had opposing consequences on EC and hormone-producing cell features. Expressed late in EEC differentiation, the latter TFs mainly bind cis-elements that are accessible in undifferentiated stem cells and tailor the subsequent expression of TF combinations that specify EEC types. Thus, TF oscillations retard EEC maturation to enable accurate EEC diversification.

molecular biology↗

Gene-environment correlation: The role of family environment in academic development

Academic achievement is partly heritable and highly polygenic. However, genetic effects on academic achievement are not independent of environmental processes. We investigated whether aspects of the family environment mediated genetic effects on academic achievement across development. Our sample included 5,151 children who participated in the Twins Early Development Study, as well as their parents and teachers. Data on academic achievement and family environments (parenting, home environments, and geocoded indices of neighbourhood characteristics) were available at ages 7, 9, 12 and 16. We computed educational attainment polygenic scores (PGS), and further separated genetic effects into cognitive and noncognitive PGS. Three core findings emerged. First, aspects of the family environment, but not the wider neighbourhood context, consistently mediated the PGS effects on achievement across development -accounting for up to 34.3% of the total effect. Family characteristics mattered beyond socio-economic status. Second, family environments were more robustly linked to noncognitive PGS effects on academic achievement than cognitive PGS effects. Third, when we investigated whether environmental mediation effects could also be observed when considering differences between siblings, adjusting for family fixed effects, we found that environmental mediation was nearly exclusively observed between families. This is consistent with the proposition that family environmental contexts contribute to academic development via passive gene-environment correlation processes, or genetic nurture. Our results show how parents tend to shape environments that foster their childrens academic development partly based on their own genetic disposition, particularly towards noncognitive skills, rather than responding to each childs genetic disposition.

genetics↗

ARBUR: a Machine Learning-based Analysis System for Relating Behaviors and Ultrasonic Vocalizations of Rats

Deciphering how different types of behavior and ultrasonic vocalizations (USVs) of rats interact can yield insights into the neural basis of social interaction. However, the behavior-vocalization interplay of rats remains elusive because of the challenges of relating the two communication media in complex social contexts. Here, we propose a machine learning-based analysis system (ARBUR) that can cluster without bias both non-step (continuous) and step USVs, hierarchically detect eight types of behavior of two freely behaving rats with high accuracy, and locate the vocal rat in 3-D space. By simultaneously recording the video and ultrasonic streams of two freely behaving rats, ARBUR reveals that rats communicate via distinct USVs when engaging in different types of social behavior. Moreover, we show that ARBUR can not only automatically reveal the well-understood behavior-associated vocalizations that were carefully concluded by other behavioral researchers, but also hold the promise to indicate novel findings that can be hardly found by manual analysis, especially regarding step USVs and the active/passive rat-associated USVs during easy-to-confuse social behaviors. This work highlights the potential of machine learning algorithms in automatic animal behavioral and acoustic analysis and could help mechanistically understand the interactive influence between the behaviors and USVs of rats.

animal behavior and cognition↗

DNA Methylation (DM) data format and DMtools for efficient DNA methylation data storage and analysis

DNA methylation is a critical epigenetic mechanism that plays a pivotal role in various biological processes. Currently, larger datasets from whole-genome bisulfite sequencing for DNA methylation pose challenges throughout the computational analysis pipeline, including storage and memory constraints. Unfortunately, storage formats and analysis tools have not kept pace with these increased resource demands. In this study, we present a new and efficient design for storing DNA methylation (DM) data after mapping in compressed binary indexed DM format. Our format significantly reduces storage space by 80%-95% compared to commonly used file formats for DNA methylation data after mapping. To enhance the processing of DNA methylation data in DM format, we have developed DMtools, a comprehensive toolkit that offers utilities such as rapid and random access, computation of DNA methylation profiles across genes, and analysis of differential DNA methylation. The analysis speed is improved by over 100 times compared to existing methods. Furthermore, we have created pyDMtools, a Python package that efficiently processes DM format files for Python users. The integration of the DM format and its associated tools represents significant progress in handling and exploring DNA methylation data, offering the potential to significantly reduce storage needs and improve downstream analysis capabilities.

bioinformatics↗

Pervasive RNA Binding Protein Enrichment on TAD Boundaries Regulates TAD Organization

Mammalian genome is hierarchically organized by CTCF and cohesin through loop extrusion mechanism to facilitate the organization of topologically associating domains (TADs). Mounting evidence suggests additional factors/mechanisms exist to orchestrate TAD formation and maintenance. In this study, we investigate the potential role of RNA binding proteins (RBPs) in TAD organization. By integrated analyses of global RBP binding and 3D genome mapping profiles from both K562 and HepG2 cells, our study unveils the prevalent enrichment of RBPs on TAD boundaries and define boundary associated RBPs (baRBPs). We also characterize chromatin features of baRBP binding and uncover clustering among baRBPs and with transcription factors (TFs). Moreover, we found that baRBP binding is correlated with enhanced TAD insulation strength and in a CTCF independent manner. Further analyses revealed that baRBP binding is associated with nascent promoter transcription thus RBP/transcription may synergistically demarcate TADs. Additional experimental testing was performed using RBFox2 as a paradigm. Knockdown of RBFox2 in K562 cells causes remarkable TAD reorganization and boundary loss. Moreover, we found RBFox2 enrichment on TAD boundaries is a conserved phenomenon in C2C12 myoblast (MB) cells. RBFox2 is down-regulated and its bound boundaries are remodeled during MB differentiation into myotubes (MTs). Knockout of Rbfox2 in MBs also causes significant boundary reorganization. Finally, transcriptional inhibition in C2C12 cells indeed decreases RBFox2 binding and disrupts TAD boundary insulation. Altogether, our findings demonstrate that RBPs can play active role in modulating TAD organization through co-transcriptional association and synergistic action with nascent promoter transcripts.

bioinformatics↗

Identification of avaC from infant gut microbial isolates that convert 5AVA to 2-piperidone with high efficiency

2-Piperidone has been identified as a biomarker for various human diseases, but its origin in vivo remains poorly understood. Furthermore, 2-piperidone is a crucial industrial raw material, and thus the discovery of novel efficient 2-piperidone synthases may have an important application in its biosynthesis. In this study, we aimed to identify the bacterial source and metabolic mechanism of 2-piperidone from a previously generated infant gut microbial culture collection. We found that 2-piperidone could be produced from 5AVA by four bacterial strains, including Collinsella aerofaciens LFYP39, Collinsella intestinalis LFYP54, Clostridium bolteae LFYP116, and Clostridium hathewayi LFYP18 from 51 bacterial strains. Furthermore, 2-piperidone could be synthesized from proline by cross-feeding between Clostridium difficile LFYP43 and Collinsella intestinalis LFYP54. We employed a gain-of-function library to identify the gene avaC (5-aminovaleric acid cyclase) which can catalyze 5AVA to produce 2-piperidone in C. intestinalis LFYP54. Homologous genes of avaC were also identified and validated in the other three bacterial strains. Gene avaC exhibits a broad distribution in the natural environmental bacteria. Overall, our research identified the gut bacterial strains and the genes that are responsible for the production of 2-piperidone. This study may facilitate the prediction of 2-piperidone-related disease risks through the analysis of gut bacterial community composition, and enhance the efficiency of 2-piperidone in its biosynthesis in industry. ImportanceIn recent decades, it has become a consensus that gut microbiota can affect host health through producing metabolites. However, the complexity of gut flora composition makes finding the sources of the particular metabolite challenging. 2-piperidone is a biomarker for various diseases and a highly valued raw material for nylons. In this study, we identified the gut bacterial strains that can transform 5AVA to 2-piperidone. A novel 2-piperidone synthase gene, avaC, was also identified and characterized. These findings provided new insights into the potential connection between 2-piperidone related diseases and the intestinal flora, as well as a possible novel approach for more efficient biosynthesis of 2-piperidone in industry.

microbiology↗

Mucosal Adenoviral-vectored Vaccine Boosting Durably Prevents XBB.1.16 Infection in Nonhuman Primates

Waning immunity and continued virus evolution have limited the durability of protection from symptomatic infection mediated by intramuscularly (IM)-delivered mRNA vaccines against COVID-19 although protection from severe disease remains high. Mucosal vaccination has been proposed as a strategy to increase protection at the site of SARS-CoV-2 infection by enhancing airway immunity, potentially reducing rates of infection and transmission. Here, we compared protection against XBB.1.16 virus challenge 5 months following IM or mucosal boosting in non-human primates (NHP) that had previously received a two-dose mRNA-1273 primary vaccine regimen. The mucosal boost was composed of a bivalent chimpanzee adenoviral-vectored vaccine encoding for both SARS-CoV-2 WA1 and BA.5 spike proteins (ChAd-SARS-CoV-2-S) and delivered either by an intranasal mist or an inhaled aerosol. An additional group of animals was boosted by the IM route with bivalent WA1/BA.5 spike-matched mRNA (mRNA-1273.222) as a benchmark control. NHP were challenged in the upper and lower airways 18 weeks after boosting with XBB.1.16, a heterologous Omicron lineage strain. Cohorts boosted with ChAd-SARS-CoV-2-S by an aerosolized or intranasal route had low to undetectable virus replication as assessed by levels of subgenomic SARS-CoV-2 RNA in the lungs and nose, respectively. In contrast, animals that received the mRNA-1273.222 boost by the IM route showed minimal protection against virus replication in the upper airway but substantial reduction of virus RNA levels in the lower airway. Immune analysis showed that the mucosal vaccines elicited more durable antibody and T cell responses than the IM vaccine. Protection elicited by the aerosolized vaccine was associated with mucosal IgG and IgA responses, whereas protection elicited by intranasal delivery was mediated primarily by mucosal IgA. Thus, durable immunity and effective protection against a highly transmissible heterologous variant in both the upper and lower airways can be achieved by mucosal delivery of a virus-vectored vaccine. Our study provides a template for the development of mucosal vaccines that limit infection and transmission against respiratory pathogens. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=166 HEIGHT=200 SRC="FIGDIR/small/565765v1_ufig1.gif" ALT="Figure 1"> View larger version (48K): org.highwire.dtl.DTLVardef@d49b9dorg.highwire.dtl.DTLVardef@347455org.highwire.dtl.DTLVardef@1c1a196org.highwire.dtl.DTLVardef@1579130_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

Induction of immortal-like and functional CAR-T cells by defined factors

Long-term antitumor efficacy of chimeric antigen receptor (CAR)-T cells depends on their functional persistence in vivo. T cells with stem-like property show better persistence, but factors conferring T cells bona fide stemness remain to be determined. Here, we demonstrate the induction of CAR-T cells into an immortal-like and functional state, termed TIF. The induction of CAR-TIF cells depends on repression of two factors: BCOR and ZC3H12A, and requires antigen or CAR tonic signaling. The reprogrammed CAR-TIF cells possess almost infinite stemness resembling induced pluripotent stem cells but retain functionality of mature T cells, which exhibit superior antitumor effect. CAR-TIF cells enter a metabolically dormant state after elimination of target cells, which persist in vivo with a saturable niche and mediate memory protection. CAR-TIF cells represent a novel state of T cells with unprecedented stemness conferring long-term functional persistence of CAR-T cells in vivo, which have broad potentials in T cell therapies.

immunology↗

Transcranial cortex-wide imaging of murine ischemic perfusion with large-field multifocal illumination fluorescence microscopy

Ischemic stroke is a common cause of death worldwide and a main cause of morbidity. Presently, computed tomography and magnetic resonance imaging are the mainstay for stroke diagnosis and therapeutic monitoring. These modalities are often limited in terms of accessibility as well as their ability to map brain perfusion with sufficient spatial and temporal resolution, particularly in the context of preclinical studies, thus calling for development of new brain perfusion techniques featuring rapid imaging speed, cost-effectiveness, and ease of use. Herein, we report on cortex-wide perfusion imaging in murine ischemic stroke with large-field multi-focal illumination fluorescence microscopy (LMI). We attained quantitative readings of hemodynamic and structural changes in cerebral vascular network and pial vessels at capillary level resolution and 80 Hz frame rate fully transcranially. The in vivo perfusion maps accurately delineated the ischemic core and penumbra, further exhibiting strong correlation with ex vivo triphenyl tetrazolium chloride staining. Interestingly, monitoring of therapeutic effects of thrombolysis in stroke has revealed that early recanalization could effectively save the penumbra whilst reducing the infarct area. Furthermore, cross-strain comparison of perfusion dynamics affirmed that C57BL/6 mice, benefiting from more extensive pial collateral recruitment, feature a larger penumbra and smaller infarct core as compared to BALB/c mice which have few or no collaterals. Finally, we apply LMI to show that sensory stimulation-based treatment enhances blood flow and abolish perfusion deficit in the ischemic core and penumbra regions. The simple, cost-effective and minimally invasive nature of the proposed approach offers new venues for brain perfusion research under various disease conditions such as stroke, neurodegeneration or epileptic seizures.

neuroscience↗

Recurrent hybridization and gene flow shaped Norway and Siberian spruce evolutionary history over multiple glacial cycles

Over the last decades, extensive genome-wide resequencing studies have highlighted the extent of hybridization and introgression between closely related species. Animal and plant species went through cycles of contractions and expansions as a result of glacial cycles. These repeated sequences of reproductive isolation and admixture at continental scales have led to the accumulation over time of an ancient, deep-seated and complex genetic structure. This structure was blurred by extensive gene flow, or reinforced by strong local adaptation. This already multi-layered structure has often been further enhanced by hybridization. We investigated this complexity in Norway spruce (Picea abies) and Siberian spruce (P. obovata), two closely related species dominating Eurasian boreal forests and forming a vast hybrid zone. Here, we genotyped 542 individuals of both species and their hybrids at 480K SNPs. Individuals came from 55 populations, extending from western Europe to Siberia with a focus on the main hybrid zone. Despite extensive gene flow and a clear Isolation-by-Distance pattern at the continental scale, distinct genetic clusters emerged, indicating barriers and corridors to migration. Coalescent-based demographic inferences revealed that Norway and Siberian spruce repeatedly hybridized during the Pleistocene with introgression pattern varying depending on the latitude. In northern ranges, P. obovata expanded into P. abies while P. abies expanded into P. obovata in the southern parts. Two cryptic refugia located in the large hybrid zone played a critical role in shaping the current distribution of the two species. Our study highlights the importance of considering the whole species complex instead of separate entities to shed light on their complex demographic histories.

evolutionary biology↗

Multi-omics analysis reveals signatures of selection and loci associated with complex traits in pigs

Selection signatures that contribute to phenotypic diversity, especially morphogenesis in pigs, remain to be further elucidated. To reveal the regulatory role of genetic variations in phenotypic differences between Eastern and Western pig breeds, we performed a systematic analysis based on seven high-quality de novo assembled genomes, 1,081 resequencing data representing 78 domestic breeds, 162 methylomes, and 162 transcriptomes of skeletal muscle from Tongcheng (Eastern) and Landrace (Western) pigs at 27 developmental stages. Selective sweep uncovers different genetic architectures behind divergent selection directions for the Eastern and Western breeds. Notably, two loci showed functional alterations by almost fixed missense mutations. By integrating time-course transcriptome and methylome, we revealed differences in developmental timing during myogenesis between Eastern and Western breeds. Genetic variants under artificial selection have critical regulatory effects on progression patterns of heterochronic genes like GHSR and BDH1, by the interaction of local DNA methylation status, particularly during embryonic development. Altogether, our work not only provides valuable resources for understanding pig complex traits, but also contributes to human biomedical research.

genomics↗

Rapid measurement and statistical ranking of leaf drought tolerance capacity in cotton

Recent progress in ecological remote sensing calls for a more rapid measurement and a closer assessment of crop drought tolerance traits under field conditions. This study addresses three main questions: (1) If leaf dry matter content (LDMC) is equally effective in indicating cotton drought tolerance as leaf osmotic potential at full turgor ({pi}o); (2) if drought tolerance is inversely related to fiber yield/quality in line with the leaf economics spectrum; and (3) if a reliable statistical model can be developed to rank cotton drought tolerance. The values of{pi} o, along with those of LDMC, of 2736 leaves obtained from cotton variety trials conducted during 2020-2022 in both dryland and irrigated regimes were measured using osmometry. The relationships between{pi} o and LDMC, as well as those between traits and lint yield and fiber quality indices, were investigated using regression analysis. A Bayesian hierarchical linear model was developed to rank cotton drought tolerance based on differences (or adjustments) in{pi} o and LDMC between dryland and irrigated sites. LDMC was not only shown to be an alternate and equally effective drought tolerance trait compared with{pi} o obtained from the widely accepted osmometry method, its use is also estimated to lead to a tenfold increase in measuring speed. A stronger drought tolerance capacity of the tested cotton varieties correlated with a lower lint yield and quality, which is generally consistent with the prediction of the leaf economics spectrum. The drought tolerance rankings using the Bayesian hierarchical model help divide the selected 17 cotton varieties into three groups: (a) more-drought tolerant, (b) less-drought tolerant, and (c) intermediate. The ranking results are interpreted using field-measured data of root distribution and diurnal leaf gas exchange from selected cotton varieties. Our work provides new opportunities for a more rapid measurement and an unambiguous ranking of drought tolerance capacity for crop genotypes under various management regimes.

ecology↗

Von Willebrand Factor Synergizes with Tumor-Derived Extracellular Vesicles to Promote Gastric Cancer Metastasis

Cells of gastric cancer invade local tissue extensively and also metastasize through the circulation to remote organs. Patients with metastasized gastric cancer have poor outcomes. Cancer cells are known to release extracellular vesicles (EVs) that contribute to cancer progression, but how cancer cell-derived EVs promote cancer growth and metastasis remains poorly understood. We have recently reported that levels of circulating gastric cancer cell-derived EVs (gcEVs) and the adhesive ligand von Willebrand factor (VWF) are associated with cancer metastasis and poor prognosis of patients, but the underlying mechanism of this gcEV-VWF interaction was not known. Here we report results from a study designed to investigate the synergistic action of VWF and gcEVs in vitro and in mouse models. We showed that VWF in cancer-bearing mice was hyperadhesive and became microvesicle-bound. EV-bound VWF mediated the adhesion of gcEVs to the endothelium to disrupt endothelial integrity and facilitate the transendothelial migration of cancer cells and pulmonary metastasis. Reducing VWF adhesive activity by the metalloprotease ADAMTS-13 or promoting gcEV clearance by the scavenging factor lactadherin prevented pulmonary metastasis in mice. These results highlight the synergistic action of gcEVs and VWF in promoting gastric cancer metastasis and identifying new targets for its prevention. Key point: Author contributionsO_LIHyperadhesive VWF becomes microvesicle-bound to induce endothelial leakage and promote the pulmonary metastasis of gastric cancer in mice. C_LIO_LIReducing VWF activity by ADAMTS-13 and accelerating microvesicle clearance by lactadherin reduces pulmonary metastasis of gastric cancer. C_LI

cancer biology↗