Search bioRxiv⌕ Search

Biology subjects

Liao, J.

Publications and source records attributed to Liao, J..

At least 55 records · Page 3Linked to original sources

Diverse quorum sensing systems regulate microbial communication and biogeochemical processes in deep-sea cold seeps

Quorum sensing is a fundamental chemical communication mechanism that enables microorganisms to coordinate behavior and adapt to environmental conditions. In deep-sea cold seep ecosystems, where diverse microbial communities thrive, quorum sensing is likely a key mechanism driving microbial interactions. However, the distribution, mechanisms, and ecological roles of quorum sensing in cold seeps remain poorly understood. To address this, we analyzed 173 metagenomes, 33 metatranscriptomes, and 18 metabolomes from 17 global cold seep sites. We identified 299,355 quorum sensing genes from the seep non-redundant gene catalog, representing 34 gene types across six quorum sensing systems, with distribution patterns influenced by sediment depth and seep type. These quorum sensing genes were present in 3,576 metagenome-assembled genomes from 12 archaeal and 108 bacterial phyla, revealing a complex network of intraspecies and interspecies communication. Microbial groups involved in key metabolic processes, such as sulfate-reducing bacteria, anaerobic methanotrophic archaea, diazotrophs and organohalide reducers, were extensively regulated by quorum sensing, influencing biogeochemical cycles of carbon, nitrogen, and sulfur. Phylogenetic analysis and protein domain identification highlighted the functional roles of key quorum sensing-related proteins (e.g., PDEs, CahR, RpfC/G and LuxR) in modulating microbial behaviors, such as motility and chemotaxis. Heterologous expression and metabolomic profiling further confirmed the activity of representative LuxI-R pairs and identified inhibitors of quorum sensing in cold seep sediments. Overall, these findings highlight complexity and significance of quorum sensing in microbial interactions, ecological adaptation, and biogeochemical cycling within cold seep ecosystems, advancing our understanding of microbial communication in the deep biosphere.

microbiology↗

Tracing Cellular Senescence in Bone: Time-Dependent Changes in Osteocyte Cytoskeleton Mechanics and Morphology

Aging-related bone loss significantly impacts the growing elderly population globally, leading to debilitating conditions such as osteoporosis. Senescent osteocytes play a crucial role in the aging process of bone. This longitudinal study examines the impact of continuous local and paracrine exposure to senescence-associated secretory phenotype (SASP) factors on senescence-associated biophysical and biomolecular markers in osteocytes. We found significant cytoskeletal stiffening in irradiated osteocytes, accompanied by expansion of F-actin areas and a decline in dendritic integrity. These changes, correlating with alterations in pro-inflammatory cytokine levels and osteocyte-specific gene expression, support the reliability of biophysical markers for identifying senescent osteocytes. Notably, local accumulation of SASP factors had a more pronounced impact on osteocyte properties than paracrine effects, suggesting that the interplay between local and paracrine exposure could substantially influence cellular aging. This study underscores the importance of osteocyte mechanical and morphological properties as biophysical markers of senescence, highlighting their time-dependence and differential effects of local and paracrine SASP exposure. Collectively, our investigation into biophysical senescence markers offer unique and reliable functional hallmarks for non-invasive identification of senescent osteocytes, providing insights that could inform therapeutic strategies to mitigate aging-related bone loss.

biophysics↗

Diverse defense systems synergistically drive the microbe-virus arms race in deep sea cold seeps

Cold seeps host diverse microbes and viruses with numerous unexplored defense and anti-defense systems. Analysis of 3,813 microbial and 13,336 viral genomes from 191 metagenomes across 17 cold seep sites reveals extensive microbial defense repertoires, with over 60% representing candidate systems. Experimental validation confirms that several candidates protect against viral infection. These defense systems frequently co-occur, suggesting potential synergistic interactions, and are broadly distributed across sediments. In response, viruses have evolved diverse anti-defense genes, and the concurrent presence of multiple viral and microbial systems highlights intricate coevolution. Functionally critical lineages, such as anaerobic methanotrophic archaea, sulfate-reducing bacteria, and diazotrophs, appear to modify their defensive strategies under ecological and environmental pressures; for example, sulfate-reducing bacteria harbor multiple Gabija systems while corresponding viruses carry anti-Gabija genes, illustrating specific coevolutionary adaptations. Overall, these findings underscore the critical role of virus-microbe interactions in shaping microbial metabolic functions and environmental adaptation in deep-sea ecosystems.

microbiology↗

Antipsychotic-like effects of the selective Rho-kinase 2 inhibitor KD025 in genetic and pharmacological mouse models of schizophrenia

1Copy number variations in the ARHGAP10 gene encoding Rho GTPase-activating protein 10 are significantly associated with schizophrenia. ARHGAP10 negatively regulates RhoA/Rho-kinase (ROCK) signaling. We previously demonstrated that fasudil, a non-selective ROCK inhibitor, exhibited antipsychotic-like effects in several mouse models of schizophrenia. ROCK has two subtypes, ROCK1 and ROCK2. ROCK1 is mainly expressed in the thymus and blood, while ROCK2 is predominantly expressed in the brain. Therefore, it is expected that like fasudil, selective ROCK2 inhibitors will exhibit antipsychotic-like effects, accompanied by a lower incidence of adverse effects due to ROCK1 inhibition. Here, we used genetic and pharmacological models of schizophrenia to investigate whether the selective ROCK2 inhibitor KD025 would show antipsychotic-like effects with a favorable adverse effect profile. Oral administration of KD025 suppressed the abnormal increase in the phosphorylation level of myosin phosphatase-targeting subunit 1, a substrate of ROCK, and ameliorated the decreased spine density of layer 2/3 pyramidal neurons in the medial prefrontal cortex of Arhgap10 S490P/NHEJ mice. Furthermore, KD025 mitigated the methamphetamine-induced impairment of visual discrimination (VD) in Arhgap10 S490P/NHEJ and wild-type mice. KD025 also reduced MK-801-induced impairments of VD, novel object recognition, and hyperlocomotion. Regarding side effects that are commonly seen with typical antipsychotics, KD025 did not affect systolic blood pressure and did not induce extrapyramidal symptoms, hyperprolactinemia, or hyperglycemia at the effective dosage in naive wild-type mice. Taken together, KD025 shows antipsychotic-like effects with a favorable adverse effect profile in genetic and pharmacological mouse models of schizophrenia.

pharmacology and toxicology↗

A COVID-19 Rapid Antigen Test Employing Upconversion Nanoparticles

The COVID-19 pandemic has underscored the critical need for rapid and accurate diagnostic tools. Current methods, including PCR and rapid antigen tests (RAT), have limitations in speed, sensitivity, and the requirement for specialized equipment and trained personnel. Nanotechnology, particularly upconversion nanoparticles (UCNPs), offer a promising alternative due to their unique optical properties. UCNPs can convert low-energy near-infrared (NIR) light into higher-energy visible light, making them ideal for use as optical probes in single molecule detection and point of care applications. This study, initiated in early 2020, explores the opportunity of using highly doped UCNPs (40%Yb3+/4%Er3+) in lateral flow assay (LFA) for the early diagnosis of COVID-19. The UCNPs-based LFA testing demonstrated a minimum detection concentration of 100 pg/mL for SARS-CoV-2 antigen and 105 CCID50/mL for inactivated virus. Clinical trials, conducted in Malaysia and Western Australia independently, showed that the technique was at least 100 times more sensitive than commercial RAT kits, with a sensitivity of 100% and specificity of 91.34%. The development process involved multidisciplinary collaborations, resulting in the Virulizer device, an automated strip reader for point-of-care testing. This work sets a reference for future development of highly sensitive and quantitative rapid antigen tests, aiming for the Limits of Detection (LoD) in the range of sub-ng/mL.

bioengineering↗

Commensal-pathogen dynamics structure disease outcomes during Clostridioides difficile colonization

Gastrointestinal colonization by Clostridioides difficile is common in healthcare settings and ranges in clinical presentation from asymptomatic carriage to lethal C. difficile infection (CDI). We used a systems biology approach to investigate why patients colonized with C. difficile have a range of outcomes. Microbiota-humanization of germ-free mice with fecal samples from toxigenic C. difficile carriers revealed a spectrum of virulence among clade 1 lineages and identified commensal Blautia associated with markers of non-pathogenic colonization. Using gnotobiotic mice engrafted with defined human microbiota, we observed strain-specific CDI severity across clade 1 strains. Yet, mice engrafted with a higher diversity community were protected from severe disease across all strains without suppression of C. difficile colonization. These results indicate that when colonization resistance has been breached without overt infection, commensals can attenuate a diversity of virulent strains without inhibiting pathogen colonization, providing insight into determinants of stable C. difficile carriage.

microbiology↗

Extracellular vesicle-derived miRNA-mediated cell-cell communication inference for single-cell transcriptomic data with miRTalk

MicroRNAs are released from cells in extracellular vesicles (EVs), representing an essential mode of cell-cell communication (CCC) via an inhibitory effect on gene expression. The advent of single-cell RNA-sequencing (scRNA-seq) technologies has ushered in an era of elucidating EV-derived miRNA-mediated CCC. However, the lack of computational methods to infer such CCC poses an outstanding challenge. Herein, we present miRTalk (https://github.com/multitalk/miRTalk), a pioneering framework for inferring EV-derived miRNA-mediated CCC with a probabilistic model and a curated database, miRTalkDB, which includes EV-derived miRNA-target associations. The benchmarking against simulated and real-world datasets demonstrated the remarkable accuracy and robustness of miRTalk. Subsequently, we employed miRTalk to uncover the in-depth CCC mechanisms underlying three disease scenarios. In summary, miRTalk represents the first approach for inferring EV-derived miRNA-mediated CCC with scRNA-seq data, providing invaluable insights into the CCC dynamics underpinning biological processes.

bioinformatics↗

Illuminating microbial phosphorus cycling in deep-sea cold seep sediments using protein language models

Phosphorus is essential for life and critically influences marine productivity. Despite geochemical evidence of active phosphorus cycling in deep-sea cold seep ecosystems, the microbial processes involved remain poorly understood. Traditional sequence-based searches often fail to detect proteins with remote homology. To address this, we developed a protein language model (PLM) named LucaPCycle that integrates sequence and structural information. This PLM-based approach identified 4,606 new phosphorus-cycling protein families based on the non-redundant gene and genome catalogs from global cold seeps, substantially enhancing our understanding of their diversity, ecology, and function. Among previously unannotated sequences, we discovered three novel alkaline phosphatase families (ALP1, ALP2 and ALP3) that feature unique domain organizations and preserved enzymatic capabilities. These results highlight previously overlooked ecological importance of phosphorus cycling within cold seeps, corroborated by data from porewater geochemistry, metatranscriptomics, and metabolomics. We identified a previously unrecognized diversity of archaea contributing to organic phosphorus mineralization and inorganic phosphorus solubilization through various mechanisms. This includes ecologically significant groups such as Asgardarchaeota, anaerobic methanotrophic archaea (ANME), and Thermoproteota. Additionally, viruses can enhance their hosts (e.g., ANME) phosphorus utilization through the PhoR-PhoB regulatory system and PhnCDE transporter, indirectly influencing methane dynamics. Overall, our PLM-based functional predictions are capable of accessing previously hidden sequence spaces for microbial phosphorus cycling, and can be applied to other various ecosystems.

microbiology↗

Unravelling the progression of the zebrafish primary body axis with reconstructed spatiotemporal transcriptomics

Elucidating the spatiotemporal dynamics of gene expression is essential for understanding complex physiological and pathological processes. Traditional technologies like in situ hybridization (ISH) and immunostaining have been restricted to analyzing expression patterns of a limited number of genes. Spatial transcriptomics (ST) has emerged as a robust alternative, enabling the investigation of spatial patterns of thousands of genes simultaneously. However, current ST methods are hindered by low read depths and limited gene detection capabilities. Here, we introduce Palette, a pipeline that infers detailed spatial gene expression patterns from bulk RNA-seq data, utilizing existing ST data as only reference. This method identifies more precise expression patterns by smoothing, imputing and adjusting gene expressions. We applied Palette to construct the Danio rerio SpatioTemporal Expression Profiles (DreSTEP) by integrating 53-slice serial bulk RNA-seq data from three developmental stages with existing ST references and 3D zebrafish embryo images. DreSTEP provides a comprehensive cartographic resource for examining gene expression and spatial cell-cell interactions within zebrafish embryos. Utilizing machine learning-based screening, we identified key morphogens and transcription factors (TFs) essential for anteroposterior (AP) axis development and characterized their dynamic distribution throughout embryogenesis. In addition, among these TFs, Hox family genes were found to be pivotal in AP axis refinement. Their expression was closely correlated with cellular AP identities, and hoxb genes may act as central regulators in this process.

developmental biology↗

Evidence of horizontal gene transfer and environmental selection impacting antibiotic resistance evolution in soil-dwelling Listeria

Soil has been identified as an important reservoir of antibiotic resistance genes (ARGs) and there is a need to understand how corresponding environmental changes influence their emergence, evolution, and spread. As a soil-dwelling bacterial genus containing important pathogens, Listeria, including L. monocytogenes, the causative agent of listeriosis in humans, could serve as a key model for establishing this understanding. Notably, acquired antibiotic resistance among L. monocytogenes isolated from foods and the environment has been observed in some regions over the past decade. Here we characterized ARGs using 594 genomes representing 19 Listeria species that we previously isolated from soils across the United States. Among the five putatively functional ARGs identified, lin, which confers resistance to lincomycin, was the most prevalent, followed by mprF, sul, fosX, and norB. ARGs were found to be predominant in Listeria sensu stricto species and species more closely related to L. monocytogenes tended to harbor more ARGs. Notably, lin, fosX, and norB showed evidence of recent horizontal gene transfer (HGT) across species, likely through transformation as opposed to conjugation and transduction, while mprF and sul appear to have undergone positive selection. In addition, soil properties and surrounding land use were identified as the most important factors associated with ARG richness and genetic divergence, respectively. Using machine learning, we demonstrated that the presence of ARGs can be predicted from environmental variables with good accuracy (mean auROC of 0.76). Collectively, our data suggest that recent HGT and environmental selection played a vital role in the acquisition and diversification of ARGs in the soil environment.

microbiology↗

RSG-YOLO: Detection of rice seed germination rate based on enhanced YOLOv8 and multi-scale attention feature fusion

The lack of obvious difference between germinated seeds and non-germinated seeds will cause the low accuracy of detecting rice seed germination rate, remains a challenging issue in the field. In view of this, a new model named Rice Seed Germination-YOLO (RSG-YOLO) is proposed in this paper. This model initially incorporates CSPDenseNet to streamline computational processes while preserving accuracy. Furthermore, the BRA, a dynamic and sparse attention mechanism is integrated to highlight critical features while minimizing redundancy. The third advancement is the employment of a structured feature fusion network, based on GFPN, aiming to reconfigure the original Neck component of YOLOv8, thus enabling efficient feature fusion across varying levels. An additional detection head is introduced, improving detection performance through the integration of variable anchor box scales and the optimization of regression losses. This paper also explores the influence of various attention mechanisms, feature fusion techniques, and detection head architectures on the precision of rice seed germination rate detection. Experimental results indicate that RSG-YOLO achieves a mAP50 of 0.981, marking a 4% enhancement over the mAP50 of YOLOv8 and setting a new benchmark on the RiceSeedGermination dataset for the detection of rice seed germination rate.

plant biology↗

Cold seeps are hotspots of deep-sea nitrogen-loss driven by microorganisms across 21 phyla

Nitrogen bioavailability, governed by the balance of fixation and loss processes, is a key factor regulating oceanic productivity, ecosystem functions, and global biogeochemical cycles. The key nitrogen-loss organisms--denitrifiers and anaerobic ammonium-oxidizing (anammox) bacteria--are not well understood in marine seafloor environments, especially in deep-sea cold seeps. In this study, we combined geochemical measurements, 15N stable isotope tracer analysis, metagenomics, metatranscriptomics, and three-dimensional protein structural simulations to investigate the diversity of denitrifying and anammox microbial communities and their biogeochemical roles in these habitats. Geochemical evidence from 301 sediment samples shows significantly higher nitrogen-loss rates in cold seeps compared to typical deep-sea sediments, with an estimated annual nitrogen loss of 6.16 Tg from seafloor surface sediments. Examination of a total of 147 million non-redundant genes reveals a high prevalence and active expression of nitrogen-loss genes, including nitrous-oxide reductase (NosZ; 6.88 genes per million or GPM on average), nitric oxide dismutase (Nod; 1.29 GPM), and hydrazine synthase (HzsA; 3.35 GPM) in surface sediments. Analysis of 3,164 metagenome-assembled genomes from this habitat has expanded the known diversity of nitrous-oxide reducers to six phyla and nitric oxide-dismutating organisms to one phylum and two new orders, while ten phyla host anammox bacteria going beyond Planctomycetota. These microbes show diverse structural adaptations and complex gene cluster arrangements that potentially enable survival in the harsh conditions of cold seeps. These findings suggest that cold seeps, despite their low temperatures, are significant, previously underestimated hotspots of nitrogen loss, potentially contribute substantially to the global nitrogen cycle.

microbiology↗

The transcripts of a gastrula-premarked enhancer prime posterior tissue development through cross-talk with morphogen effector

The regulatory mechanisms governing cell fate determination, particularly lineage diversification during mammalian embryonic development, remain poorly understood with in-depth regulatory paradigms yet to be fully elucidated. Here, leveraging the epigenetic landscape of mouse gastrula, we identified p-Enh, a pre-marked enhancer in primitive streak region, as pivotal regulator for posterior tissue development in mouse embryos. Morphological and single-cell transcriptomic analyses confirmed embryonic lethality phenotype with disrupted posterior tissue development trajectories in p-Enh-KO embryos. Molecularly, apart from regulating the neighboring coding-gene Cdx2 in cis, our findings suggest that p-Enh also modulate the global transcriptome and epigenomic landscape, which might through the transient production of eRNA in trans. Further investigation revealed p-Enh participate in the regulatory cascades of TGF-{beta} signaling. Chemical modulation of TGF-{beta} signaling can largely rescue the posterior development deficiency in in vitro gastruloids through a Cdx2-independent mechanism. Thus, we propose a potential model in which the broadly distributed p-Enh transcripts within the nucleus could serve as essential cross-modular coordinators, priming the posterior development of mouse embryo.

developmental biology↗

Population genomics of the rice landrace Acuce reveals exceptional dynamics of immune receptors

In cultivated plants such as Oryza sativa, landraces harbour high levels of diversity, in sharp contrast with genetically uniform modern varieties. The Yuanyang terraces (China) are renowned for traditional farming involving landraces and low disease incidence. To understand the molecular basis of these resistance levels, we explored the genomic diversity of Acuce, one of the oldest landraces in the region. Based on whole-genome resequencing of over 200 Acuce plants, we evaluated the diversity of immunity and agronomical genes with respect to the rest of the genome. In parallel, we analysed the genetic basis of pathogen resistance and agronomical traits. Acuce exhibits high levels of diversity, reaching 38% of the worldwide levels. We uncovered an excess of diversity and signatures of directional selection associated with immunity genes, in contrast with agricultural traits. Furthermore, cultures of mixed genotypes exhibited superior performances for both pathogen resistance and agricultural traits. We showed that, within one single landrace, traditional farmer practices selected optimal agricultural traits while maintaining diversity enabling pathogen resistance. This study elucidates the complex interplay between genetic diversity, natural selection related to pathogens, and selection for agricultural traits within traditional landraces, providing insights into sustainable agricultural practices in diverse cropping systems.

genomics↗

Granulosa cell-layer stiffening prevents the granulosa cells from escaping the post-ovulatory follicle

Ovulation is necessary for successful reproduction. After ovulation, cumulus cells and oocytes are released, while granulosa cells (GCs) remain trapped within the post-ovulatory follicle to form the corpus luteum. However, the mechanism underlying GC confinement has long been unclear. Here, we provide in vitro and in vivo evidence demonstrating that the stiffening of GC-layer as an evolutionarily conserved mechanism that hinders GCs from escaping the post-ovulatory follicles. Spatial transcriptome analysis reveals that the assembly of focal adhesions is primarily responsible for this stiffening. Disrupting focal adhesion assembly through RNA interference results in the release of GCs from the post-ovulatory follicle, leading to the formation of an aberrant corpus luteum with reduced cell density and cavities. We also uncover that the LH (hCG) -cAMP-PKA-CREB signaling axis stimulates focal adhesion assembly and induce GC-layer stiffening. Our findings introduce a novel concept of "GC-layer stiffening", which offers valuable insights into the factors that prevent GCs escape from the post-ovulatory follicle.

cell biology↗

Variation in the response to antibiotics and life-history across the major Pseudomonas aeruginosa clone type (mPact) panel

Pseudomonas aeruginosa is a ubiquitous, opportunistic human pathogen. Since it often expresses multidrug resistance, it is ranked by the World Health Organization among the top 3 high priority pathogens, for which new treatment options are urgently required. An evaluation of new treatments is usually performed experimentally with one of the canonical laboratory strains (e.g., PAO1 or PA14). However, these two strains are unlikely representative of the strains infecting patients, because they have adapted to laboratory conditions and do not capture the enormous genomic diversity of the species. Here, we characterized the major P. aeruginosa clone type (mPact) panel. This panel consists of 20 strains, which reflect the genomic diversity of the species, cover all major clone types, and have both patient and environmental origins. We found significant strain variation in distinct responses towards antibiotics and general growth characteristics. Only few of the measured traits are related, and if so, only for specific antibiotics. Moreover, high levels of resistance were only identified for clinical mPact isolates and could be linked to known AMR (antimicrobial resistance) genes in the sequenced genomes. One strain also produced highly unstable AMR, indicating an evolutionary cost to resistance expression. By linking isolation source, growth, and virulence to life history traits, we further identified specific adaptive strategies for individual mPact strains towards either host processes or degradation pathways. Overall, the mPact panel provides a reasonably sized set of distinct strains, enabling in-depth analysis of new treatment designs or evolutionary dynamics in consideration of the species genomic diversity. ImportanceNew treatment strategies are urgently needed for high risk pathogens such as the opportunistic and often multidrug resistant pathogen Pseudomonas aeruginosa. Here, we characterize the major P. aeruginosa clone type (mPact) panel. It consists of 20 strains with different origins that cover the major clone types of the species as well as its genomic diversity. This mPact panel shows significant variation in (i) resistance against distinct antibiotics, including several last resort antibiotics, (ii) related traits associated with the response to antibiotics, and (iii) general growth characteristics. We further developed a novel approach that integrates information on resistance, growth, virulence, and life-history characteristics, allowing us to demonstrate the presence of distinct adaptive strategies of the strains that focus either on host interaction or resource processing. In conclusion, the mPact panel provides a manageable number of representative strains for this important pathogen for further in-depth analyses of treatment options and evolutionary dynamics.

microbiology↗

How antimicrobial heteroresistance promotes bacterial adaptation to antimicrobial therapy - or not

Withdrawal StatementThe authors have withdrawn their manuscript owing to inconsistencies of results during a re-assessment of the experimental work, which now question main conclusions drawn and which require additional experiments. Therefore, the authors do not wish this work to be cited as reference for the project. If you have any questions, please contact the corresponding author

evolutionary biology↗

Charge-Patterned Disordered Peptides Tune Intracellular Phase Separation in Bacteria

Subcellular phase separated compartments, known as biomolecular condensates, play an important role in the spatiotemporal organization of cells. To understand the sequence-determinants of phase separation in bacteria, we engineered protein-based condensates in Escherichia coli by utilizing electrostatic interactions as the main driving force. Minimal cationic disordered peptides were used to supercharge negative, neutral, and positive globular model proteins, enabling their phase separation with anionic biomacromolecules in the cell. The phase behavior was governed by the interaction strength between the cationic proteins and anionic biopolymers in addition to the protein concentration. The interaction strength primarily depended on the overall net charge of the protein, but the distribution of charge between the globular and disordered domains also had an impact. Notably, the protein charge distribution between domains could tune mesoscale attributes such as the size, number, and subcellular localization of condensates within E. coli cells. The length and charge density of the disordered peptides had significant effects on protein expression levels, ultimately influencing the formation of condensates. Taken together, charge-patterned disordered peptides provide a platform for understanding the molecular grammar underlying phase separation in bacteria. HighlightsO_LIMinimal disordered cationic peptides of varying charge densities can promote protein phase separation in bacterial cells. C_LIO_LIProtein net charge and charge-patterning are distinct determinants of phase behavior. C_LIO_LIProtein charge distribution can be used to tune the size, number, position, and reversibility of condensates. C_LIO_LIMultiple proteins can be selectively recruited to synthetic condensates with disordered cationic peptides. C_LI

synthetic biology↗