Biology subjects

Liang, J.

Publications and source records attributed to Liang, J..

At least 19 recordsLinked to original sources

bioRxiv2026

Hydrogel dimensionality directs mechanics-dependent nascent matrix deposition by tendon fibroblasts

Tendon fibroblasts continuously synthesize and remodel extracellular matrix (ECM) in response to their surrounding mechanical environment in vivo and in vitro, yet how dimensionality regulates the deposition of newly synthesized matrix remains poorly understood. Here, we investigated nascent matrix deposition by primary mouse tail tendon fibroblasts cultured on flat two-dimensional (2D) or encapsulated within three-dimensional (3D) norbornene-modified hyaluronic acid hydrogels with tunable mechanical properties. Newly synthesized matrix was visualized using metabolic labeling with azido-galactosamine (GalNAz), which labels nascent glycoproteins deposited during culture. In 2D, increasing hydrogel elastic modulus from 10 to 25 kPa enhanced nascent matrix deposition. This response was accompanied by increased cell spreading and YAP nuclear localization, indicating increased cellular mechanosensing. In contrast, tendon fibroblasts encapsulated within enzymatically degradable 3D hydrogels showed progressive matrix deposition over time but deposited less nascent matrix in stiffer (~50 kPa) hydrogels compared with softer 5 and 10 kPa hydrogels. YAP nuclear localization was increased in softer hydrogels compared with 50 kPa hydrogels. Bulk RNA sequencing showed increased expression of tendon matrisome-associated genes in softer 3D hydrogels, including increased tenascin C and collagen type I expression. These findings demonstrate that hydrogel dimensionality determines the relationship between matrix mechanics and nascent matrix deposition. This work establishes a framework for studying how engineered microenvironments regulate the matrix-producing behavior of tendon fibroblasts and provides insight into the design of biomaterials for investigating tendon biology and matrix remodeling.

bioengineering↗

bioRxiv2026

The circ_0074371/miR-4738-3p/AMPK Signaling Axis Induces M1 Macrophage Polarization and Restricts Intracellular Survival of Mycobacterium tuberculosis

Tuberculosis, an infectious disease caused by Mycobacterium tuberculosis, remains endemic in regions where it is prevalent. Mycobacterium tuberculosis is an intracellular pathogen that can survive within host macrophages; however, the mechanisms governing its long-term persistence and the progression to active pulmonary tuberculosis remain poorly understood. Circular RNAs (circRNAs) have been implicated in the initiation and progression of numerous diseases. In our previous study, circRNA sequencing identified several circRNAs associated with tuberculosis progression. In the present study, sequencing and reverse transcription-polymerase chain reaction (RT-PCR) analyses revealed that Circ_0074371 was significantly downregulated in monocytes from patients with active pulmonary tuberculosis (ATB) and was closely associated with disease onset and progression, exhibiting considerable diagnostic value for ATB. Functional experiments further showed that Circ_0074371 significantly impaired the intracellular survival of Mtb and promoted M1 macrophage polarization. Mechanistically, Circ_0074371 acted as a competing endogenous RNA by sequestering miR-4738-3p, a potent negative regulator of AMP-activated protein kinase (AMPK) activation. Collectively, these findings identify Circ_0074371 as a tuberculosis-associated circRNA that regulates AMPK activity and reveal a novel mechanism through which Circ_0074371 influences macrophage polarization via the AMPK pathway, providing new insights into potential therapeutic targets for ATB.

immunology↗

bioRxiv2026

Survival-associated cellular communication networks in human solid cancers

Single-cell atlases have enabled the prediction of human cell-cell communication (CCC) networks in cancer, but whether predicted communication networks have clinical significance is not well understood. Here, we integrated a pan-solid cancer scRNA-seq atlas comprising 78 cell types from 318,426 quality-controlled cells with bulk RNA-seq and clinical outcome data from The Cancer Genome Atlas (TCGA) to develop Single-cell-based Kaplan-Meier Analysis Network (SKyNet). SKyNet prioritizes ligand-receptor interactions associated with overall survival across 11 human solid cancers, predicting unique interactions not inferred by previous CCC algorithms. In pancreatic adenocarcinoma, SKyNet-predicted endothelial-pericyte interactions were associated with poor outcomes that were validated by independent spatial transcriptomics and survival cohorts. In lung adenocarcinoma, lymphatic endothelial cell interactions consisting of collagen-integrin pairs were associated with poorer survival outcomes. In kidney renal clear cell carcinoma and kidney renal papillary cell carcinoma, fibroblast communication networks displayed disparate survival associations, with the DSC2-DSG2 axis associated with better survival outcomes. Thus, SKyNet provides a hypothesis-generating framework for cell type-specific communication pathways associated with patient outcomes.

systems biology↗

bioRxiv2026

Live imaging reveals oocyte membrane pre-remodeling forming permissive space for asymmetric division

Abstract Successful oocyte maturation requires first polar body (PB1) extrusion, yet how the oocyte prepares for this asymmetric event remains unclear. Live membrane imaging of mouse oocytes reveals pronounced regional heterogeneity in plasma-membrane dynamics, generating an early polarized pattern across the surface. Whereas most of the oocyte surface and its microvilli remain relatively stable, a discrete membrane domain collapses and retracts around germinal vesicle breakdown (GVBD), separating from the zona pellucida to establish a pre-extrusion space (PES). Transient oocyte comb-like protrusions arise within the PES and subsequently collapse, converting the protrusion-filled region into an open cavity before PB1 extrusion. Mechanistically, early ERK28 dependent dissociation of the cortical scaffold ZO-1 is required for this space to form. ERK2 phosphorylates ZO-1, suppresses its phase separation, and promotes its removal from the cortex. Blocking MEK-ERK signaling prevents ZO-1 dissociation, abolishes pre-extrusion space formation, and impairs PB1 extrusion, whereas ERK activation restores these events in aged oocytes. Together, our findings identify a membrane collapse-based pre-remodeling mechanism that licenses PB1 extrusion and reveal ERK-ZO-1 signaling as a key regulator of oocyte maturation.

cell biology↗

bioRxiv2026

Multi-omics reveals accumulation mechanisms underlying differences in sesquiterpenoid content across different growth environments of Atractylodes macrocephala rhizome

This study aimed to explore mechanisms driving differential sesquiterpenoid accumulation in Atractylodes macrocephala rhizome (AMR) under different growth environments. Root and rhizosphere soil samples were collected from wild, imitated wild, one- and two-year cultivated AMR. Combined metabolomic, transcriptomic and microbiomic profiling was carried out to investigate alterations in sesquiterpenoid levels, root-associated microbiota, and terpenoid biosynthetic genes under different growth environments. Metabolomics revealed that wild AMR exhibited higher pyruvate consumption and accumulated more atractylone and atractylenolides. Transcriptomic analysis demonstrated that the genes encoding key MEP pathway enzymes (DXS, DXR, MCT, HDS) and the genes encoding the sesquiterpenoid biosynthetic enzyme GDS were significantly upregulated in wild AMR. In contrast, the genes encoding triterpenoid synthetic enzymes (SQS, SQE, {beta}-AS) were downregulated, redirecting metabolic precursors toward sesquiterpenoid synthesis. Microbial community structures differed substantially across groups. Further analysis suggested rhizosphere microorganisms were important contributors to AMR medicinal quality, and sesquiterpenoid metabolites accumulated in AMR roots, together with the rhizosphere microenvironment, jointly shape specific rhizosphere fungal assembly. This study systematically revealed the synergistic regulatory relationships among sesquiterpenoids metabolism, gene expression, growth environment, and root-associated microbes, providing multi-omics evidence for clarifying the mechanism by which these factors coordinately regulate the quality of AMR.

plant biology↗

bioRxiv2026

Complex enzyme active site scaffolding by iteratively detuned catalytic guidance

De novo enzyme design requires sequences whose structures reproduce prescribed catalytic geometries. This remains challenging for active sites that couple multiple catalytic residues, cofactors and substrates. Here we introduce the Catalytic Guidance Engine (CaGE), which optimizes designed sequences to satisfy complex sets of functional constraints by alternating constraint guided structure prediction trajectories with sequence design, gradually fading the strength of the constraint information over cycles to nudge the designed sequence towards satisfying all the constraints. We train RF3 to accept atom-pair distances and other design conditions, and use classifier-free guidance to fade their influence over multiple design cycles. We also develop training-free motif guidance protocols which operate at inference time by directly adjusting selected atoms towards the design target geometry during diffusion sampling. CaGE improves catalytic-motif geometry across a diverse enzyme benchmark and yields sequences that recover complex target active sites in independent AF3 predictions. We experimentally demonstrate the power of CaGE by designing active enzymes with complex catalytic sites: a nonheme-iron design positions four active-site residues around an iron centre and a transition-state ligand, and a PLP-dependent design positions four catalytic residues around a PLP cofactor with multiple functional groups. Active site substitutions and a 2.7[A] crystal structure support the designed mechanisms and structures. Thus, CaGE provides a route to functional de novo enzymes with complex active sites.

bioengineering↗

bioRxiv2026

Thermodynamically controlled biokinetics modelling of a lindane-degrading anaerobic enrichment culture

The anaerobic biotransformation of lindane ({gamma}-hexachlorocyclohexane), a persistent legacy pesticide and challenging subsurface contaminant was modelled using an integrated Monod biokinetics framework. Calibrated against batch experimental data, this model accounted for the dissolution of solid phase lindane and the thermodynamics of reactions involved. The study focused on a methanogenic, lindane-degrading enrichment culture (GT2) that used ethanol as the electron donor, where ethanol fermentation supplied hydrogen to support reductive dechlorination of lindane. A Dehalobacter strain was identified as the lindane-degrading organism, while a member of bacterial order Geobacterales carried out ethanol fermentation. First-order decay constants for lindane-degrading Dehalobacter were estimated from experimental data and showed variation across different growth conditions. The biokinetics model captured interactions among key microbial processes, namely lindane dechlorination, ethanol fermentation, hydrogenotrophic methanogenesis, and acetoclastic methanogenesis. Thirteen biokinetics parameters including maximum substrate utilization rates (k), half-velocity constants (Ks), and decay constants for these microbial processes were estimated through a Bayesian optimization approach. Global sensitivity analysis showed that eight parameters, primarily k and Ks, had significant linear impact on the model output, whereas responses to decay constants were more variable and potentially non-linear. This study proposed an effective modelling approach for characterizing syntrophic microbial growth within enrichment cultures and provides valuable biokinetics parameters estimates for real-world applications of anaerobic lindane bioremediation.

microbiology↗

bioRxiv2026

A virus co-opts vector's m⁶A machinery for adaptive compensation

Insect vectors harbor diverse viruses that threaten human health and agricultural production, yet the genetic basis of mutualistic virus-vector interactions remain elusive. This underscores a long-standing paradox in pest management: viruses that cause destructive diseases also facilitate vector adaptation in ways that benefit both parties. Here we show that the globally devastating tomato yellow leaf curl virus (TYLCV) acts as a Cooperative Partner, co-opting its vector's m6A epitranscriptomic machinery to offset the reproductive fitness costs of neonicotinoid resistance in the whitefly. In resistant vectors, TYLCV infection alleviates reproductive deficits via the m6A-dependent pathway, where the methyltransferase METTL14 and demethylase ALKBH4 coordinately stabilize vitellogenin (Vg) transcripts to boost female fecundity. Mechanistically, the viral C2 and CP proteins directly interact with METTL14 and ALKBH4, respectively, remodeling their RNA binding affinity to facilitate mA modification on Vg. Disrupting either of these viral-vector protein interactions restores a reproductive cost phenotype in viruliferous resistant vectors, offering novel targets for sustainable pest control. Our findings uncover a fundamental role of epigenetic marks in adaptive trait, reshaping beneficial virus-vector relationships and providing new insights for innovative public health and crop protection strategies to address global challenges.

microbiology↗

bioRxiv2026

RNA m6A demethylase ALKBH4 governs whitefly development

N6-methyladenosine (m6A) modification is the most predominant and ubiquitous internal modification of RNA in eukaryotes, serving as a key post-transcriptional regulator of gene expression that is dynamically modulated by methyltransferases (writers) and demethylases (erasers). However, while the functions of m6A methylases have been partially elucidated in insects, the identity of m6A erasers in arthropods and their chemical catalytic mechanisms, as well as biological functions, remains largely enigmatic. Here, we uncovered 2499 putative methylase genes and 1148 putative demethylase genes in 266 insect genomes, and demonstrated that ALKBH4 functions as an m6A demethylase in the whitefly, Bemisia tabaci, catalyzing the oxidative reversal of mRNA m6A modifications both in vitro and in vivo. Furthermore, we established that ALKBH4, in coordination with other core components of the m6A pathway, fulfills an essential function in regulating the transcript stability of Imaginal Disk Growth Factor 1 (IDGF1) during whitefly development. Collectively, our findings expand the evolutionary scope of the eukaryotic m6A modification system, and reveal a conserved yet insect-specific epitranscriptomic regulatory mechanism governing fundamental physiological processes and adaptive phenotypes. Significance statementThe addition of a methyl group to the N6-position of adenosine (m6A) is a highly abundant chemical modification of RNA. However, the functional role of m6A in insects and the key enzymes that regulate its levels remains poorly understood. In this study, we explored putative methylase genes and demethylase genes in hundreds insect genomes, and identified an m6A RNA demethylase, ALKBH4, in the whitefly, Bemisia tabaci. We demonstrate that ALKBH4 oxidatively reverses mRNA methylation in vivo and in vitro, in combination with other components of the m6A pathway, plays an important role in whitefly development. These findings provide new insight into m6A methylation system of insect.

zoology↗

bioRxiv2026

Placental invasion mismatch underlines pregnancy disorders and cancers

Mammalian placentas vary dramatically in invasiveness, parallel aggressive cancers, and are dysregulated in pregnancy disorders, yet whether they share regulatory architecture remains unclear. We investigated single-cell transcriptomes of the maternal-fetal interface across nine mammals spanning all major placental morphotypes and integrated it with thirteen cancers and five pregnancy complications. A conserved cellular framework is deployed through three discrete regulatory programs: a cancer-like program in hemochorials, endothelial-cooperation program in endotheliochorials, and collagen-rich invasion-suppressing program in epitheliochorials. Aggressive cancers selectively converge on hemochorial program, and we functionally validated share invasion regulators including the VGLL3-TEAD1 interaction and APOE. Pregnancy disorders are partially, mismatched deployments of these programs; placental APOE knockdown in mice phenocopies preeclampsia with concurrent collapse of both M1/M2 macrophage programs. These findings unify placental diversity, cancer convergence, and obstetric disorders under a regulatory-mismatch principle, whereby evolved placental invasion programs becomes pathological when deployed outside their evolutionary context.

evolutionary biology↗

bioRxiv2026

SPEAK: Spatial Prompting with Expert Aligned Knowledge for Tissue Domain Identification in Spatial Transcriptomics

Spatially resolved transcriptomic (SRT) data requires spatial domain identification to enable tissue microenvironment-specific downstream analyses. Here we present SPEAK (Spatial Prompting with Expert-Aligned Knowledge), a large language model (LLM)-based method to identify spatial domains from SRT data by taking advantage of the prior knowledge from both LLM and human experts. SPEAK constructs a spatial context prompt for each cell/spot based on cell types and marker genes of its neighboring cells, enabling zero-shot inference, expert-guided fine-tuning, and prototype updating through two-stage prompting. Applications to STARmap, Visium, MERFISH and Xenium datasets showed advantages of SPEAK over existing spatial domain identification methods in domain prediction accuracy, robustness to limited prior knowledge, biological interpretability, and capacity for efficient expert-guided fine-tuning with generalizability to other tissue sections.

bioinformatics↗

bioRxiv2026

Systematic Profiling and Functional Characterization of Alternative Splicing in C. elegans Olfactory Learning

Alternative splicing (AS) is prevalent in neuronal gene expression. However, its function in learning has not been systematically characterized. Here, by profiling pan-neuronal translatome changes during a C. elegans learning paradigm, we show that AS remodels expression of neuronal genes with critical function in learning at the genome-wide scale. Intriguingly, AS operates on a functionally distinct gene set from those showing transcript abundance changes, serving as a separate regulatory layer in response to experience. Specifically, a neuronally enriched worm ortholog of a mitochondrial DNA helicase twnk-1 displays significant learning-associated AS changes, with both isoform types acting in a pair of sensory neurons to regulate learning with distinct functions. AS of twnk-1 modulates a cell-nonautonomous signal from neuronal mitochondria to peripheral tissues to regulate physiological states critical for learning. These results establish AS as a systematic regulator of learning and mechanistically reveal how AS shapes physiological states to facilitate learning.

neuroscience↗

bioRxiv2026

Cell-Cell-Seq resolves contact-associated NK cell activation in defined tumor cell dyads

Cell-cell interactions shape immune recognition, but most single-cell transcriptomic methods measure cells after their interaction history has been lost or inferred. Here we apply Cell-Cell-Seq, a Nanovial-based workflow for sequencing defined cell pairs, to resolve contact-associated activation of natural killer cells paired with leukemia targets. Nanovials enabled controlled dyad formation, incubation, flow enrichment and droplet-based sequencing while reducing uncontrolled partner exchange and aggregation seen in suspension co-culture. Cell-Cell-Seq recovered a reproducible activation program marked by chemokine, cytokine, cytotoxic and immediate-early response genes. Compared with randomly mixed suspension co-culture, defined dyads emphasized contact-proximal activation, whereas suspension co-culture showed stronger features of early overstimulation. Dyad-resolved measurements also benchmarked computational models of cell-cell communication, identifying inferred signalling axes that were recovered and contact-induced programs missed by current approaches. These results establish Cell-Cell-Seq as a scalable strategy for mapping how defined immune-tumour encounters reshape cell state.

bioengineering↗

bioRxiv2026

Scalable in vivo cardiac functional genomics with compressed AAV-Perturb-seq reveals a common mitochondrial response to perturbation

Efficient identification of new targets to treat human disease requires a scalable way to link genotype to phenotype directly in the target organ. Pooled CRISPR screening with single-cell RNA sequencing as a readout (Perturb-seq) has emerged as a method for functional genomics but is typically applied in vitro and is limited in scale. Here, we combine in vivo Perturb-seq via adeno-associated virus (AAV)-mediated delivery with a statistical framework allowing for signal deconvolution after multiple random perturbations per cell (compressed Perturb-seq), to develop in vivo compressed AAV-Perturb-seq, a scalable way to perform high-throughput, cell-autonomous functional genomics in a desired target organ. We apply this approach to study the effect of 585 gene knockouts on the cardiomyocyte transcriptome. We identify that alterations in the mitochondrial transcriptome are a common response to genetic perturbation, a finding independently validated across species and perturbation modalities. We identify very few synergistic perturbations, despite observing frequent combinatorial effects. Broadly, our work establishes a platform to facilitate in vivo functional genomics in a target organ with direct applicability to identifying therapeutic targets for the treatment of human disease.

genomics↗

bioRxiv2026

Dominant resistance alleles accelerate population suppression by CRISPR-based gene drive

CRISPR-based gene drive is a promising strategy for pest control. However, when targeting a recessive fertility gene, nonfunctional resistance alleles generated by end-joining slow the spread of drive and can even impair suppressive power. It was recently discovered that a doublesex target site can result in dominant female-sterile alleles when disrupted. It could serve as an ideal target for suppression drives, as disrupted alleles are efficiently removed when inherited by a female, increasing the suppressive power of the drive. Here, to better understand how dominant sterile target sites can improve suppression, we used an individual-based, continuous space model to investigate chasing dynamics of homing drives that produce dominant female-sterile resistance. Our results indicate that dominant-sterile resistance allows homing drives to achieve higher population elimination rates and a lower probability of chasing over a broader range of performance parameters. In addition, we propose a confined gene drive system, termed TADFI (Toxin-Antidote Dominant Female Intersex), that is also based on formation of dominant female sterile alleles. TADFI has two variants, designed for population suppression and modification, respectively. We estimate the introduction frequency threshold of TADFI in a panmictic model, and evaluate its suppression dynamics in a spatial model. Though spreading less rapidly than Toxin-Antidote Dominant Embryo (TADE) suppression drive, it has similar favorable dynamics related to confinement and suppressive power, while potentially being easier to construct. Together these results show that drives generating dominant-female sterile alleles may be promising candidates for a variety of population suppression applications.

genetics↗

bioRxiv2026

Disentangling polymer confinement from specific-folding interactions reveals the drivers of E. coli chromosome organization

The three-dimensional organization of the bacterial chromosome is critical for gene regulation. Chromosome conformation capture (Hi-C) has enabled genome-wide mapping of chromosomal folding, yet ensemble-averaged contact maps entangle biologically specific-folding interactions (SFIs) with nonspecific polymer compaction and mask single-cell heterogeneity. Here, we developed a polymer-based simulation framework in E. coli to address these limitations. We found that a null model of 300,000 random polymer configurations recapitulated the global chromosomal organization observed in Hi-C data, establishing that most Hi-C signals reflect generic polymer behavior in a confined volume. Contrasting null-model predictions with experimental Hi-C data isolated a small subset of SFIs (< 7%) and generated a specific-fold ensemble of 20,000 single-cell conformations that reproduced chromosomal interaction domains and single-cell heterogeneity. SFIs were enriched in the ter region, reduced nucleoid accessibility, colocalized with cryptic prophages, and depleted in positively supercoiled regions. H-NS and MatP emerged as major chromosome-wide and local determinants of SFIs, respectively. Furthermore, high-SFI regions correlated with stress-adaptive genes, whereas low-SFI regions harbored housekeeping genes. Together, our results established that a small number of biologically encoded SFIs superimposed on a polymer background shape the E. coli chromosome and gene expression, providing a quantitative framework for dissecting chromosome architecture and function.

genomics↗

bioRxiv2026

An automated genetic screen identifies modulators of stress-induced sleep in Caenorhabditis elegans

Animals sleep more when they are sick. In C. elegans, stress-induced sleep (SIS) follows cellular injury such as exposure to ultraviolet (UV) light. The genetic regulators of SIS remain incompletely defined. Using a worm picking robot, multi-well WorMotel imaging, and association analysis we performed a semi-automated screen of 941 whole genome sequenced Million Mutation Project (MMP) strains. We quantified behavioral activity and quiescence before and after ultraviolet (UV) radiation. We applied the Sequence Kernel Association Test (SKAT) to this behavioral data to prioritize 6,663 genes and observed significant enrichment of known SIS genetic regulators. Based on these results, we conducted a candidate validation screen for additional genes regulating SIS. We identified three genes (strd-1, egl-8, cla-1), mutations in which reproducibly influence SIS. Further exploration of these genes holds potential for enhancing our understanding of the molecular basis of SIS. These findings establish a pipeline for automated behavioral phenotyping coupled with gene-based association to accelerate studies of C. elegans neurogenetics.

genetics↗

bioRxiv2026

Intranuclear polyglycine aggregation drives neurodegeneration through epigenetic repression of chromatin accessibility and transcription

Polyglycine (polyG) proteins translated from expanded GGC trinucleotide repeats are implicated in a growing group of neuromuscular degenerative disorders characterized by intranuclear inclusions, yet the pathogenic importance of aggregate localization and the mechanisms underlying polyG-induced neurodegeneration remain unclear. Here we show that intranuclear polyG aggregates are markedly more pathogenic than cytoplasmic aggregates in cellular and mouse models. Intranuclear aggregation causes greater cell death, more severe behavioral deficits and neuropathology, and earlier mortality. Mechanistically, intranuclear polyG aggregates impair nascent RNA synthesis and are associated with a transcriptionally repressive chromatin state marked by globally reduced chromatin accessibility, decreased H3K27 acetylation, and increased HDAC3 expression across cellular, mouse, and human disease tissue. Using a light-inducible system, we further show that this transcriptional impairment depends on insoluble intranuclear aggregate formation rather than diffuse polyG alone. Pharmacological HDAC inhibition partially restores histone acetylation and transcriptional output and ameliorates behavioral and pathological abnormalities. Together, these findings identify intranuclear polyG aggregates as the more pathologically relevant species and uncover epigenetic repression of chromatin accessibility and transcription as a potentially common mechanism underlying polyG diseases.

neuroscience↗