Biology subjects

Liu, M.

Publications and source records attributed to Liu, M..

At least 37 records · Page 2Linked to original sources

bioRxiv2026

Computer-aided drug screening of anti-Neobenedenia melleni drugs based on annexin B1 in farmed pearl grouper

Monogenean capsalids of the genus Neobenedenia are widespread parasites of wild and farmed marine fish, and represent a great threat to the mariculture of grouper in China. Fishery drug development to screen and find effective compounds to control and prevent the disease is urgent needed, considering the vast production of grouper in China (294 ktons in 2025). Annexins have been discovered in Neobenedenia and other parasites, and marked differences between the parasite annexins and those of the hosts make them potentially attractive drug targets for anti-parasite therapeutics. Herein, we utilized computer-based drug discovery screens using unique Neobenedenia melleni annexin B1 and a database of 1,456,161 small molecules. The 3D structure of annexin B1 was firstly modeled by three different protein prediction tools, namely AlphaFold 3, SWISS-MODEL, and I-TASSER, of which the most accurate protein structure was used as the drug target for the following structure-based virtual screening. In vivo experimental validation of 11 compounds after molecular docking shows that abamectin (Aba) has the most effective anti-Neobenedenia bioactivity at the concentration of 0.16 mg/L as the initial screening concentration. Given its low toxicity to host grouper (24 LC50=0.254 mg/L), abamectin was chose for further investigation. A 24 h bath exposure successfully lowered the parasitic load in infected grouper, yielding an 24 h EC50 of 0.033 mg. To elucidate the anti-parasite mechanism, long-timescale molecular dynamics simulations (1000 ns) of annexin B1 and Aba was conducted, which allowed for atomic and molecular-level analysis of the essential protein motions involved in the interaction of annexin B1 and its substrate. The interaction profile between annexin B1 and abamectin was dominated by hydrophobic contacts and water bridges, involving residues TYR-210, GLU-214, GLU-244, and SER-247, which path a way for further drug optimization.

zoology↗

bioRxiv2026

Parietal Cortex Transcriptomics Refines Parkinson Disease GWAS Nomination and Highlights STAT3 as a Putative Upstream Glial Regulator

Parkinson disease (PD) affects more than 1.1 million individuals in the United States and around 12 million worldwide. Although Genome Wide Association Studies (GWAS) have substantially advanced our understanding of PD genetic architecture, the regulatory mechanisms linking PD risk loci to disease-relevant gene expression remain incompletely characterized, limiting our ability to infer disease mechanisms from genetic associations. Here, we integrated disease-state parietal cortex transcriptomics with the International Parkinsons Disease Genomics Consortium (iPDGC) locus prioritization to refine PD gene nomination and identify biologically plausible candidates missed by GWAS-only approaches. Using bulk RNA-seq from 99 neuropathologically confirmed PD cases and 30 neuropathologically confirmed controls, we prioritized candidate genes across 78 loci and classified them according to concordance between genetic evidence and differential expression in diseased cortices. This integrative approach recovered candidate genes not captured by external GWAS-based prioritization methods and highlighted synaptic, lysosomal, and proteostasis pathways as major components of PD risk biology. Network and transcription factor analyses further suggested coordinated regulation of these genes, with STAT3 emerging as a putative upstream glial regulator. Together, these findings suggest that integrating disease-state transcriptomics with genetic prioritization can refine PD risk-gene nomination and uncover regulatory programs that may be missed by GWAS alone.

neuroscience↗

bioRxiv2026

Patterns and environmental drivers of amphibian alpha and beta diversity in the Huangshan Mountains, southern Anhui, China

Understanding the spatial patterns of biodiversity and their environmental determinants is fundamental to ecology and conservation, particularly in mountainous transitional zones where species assemblages can shift rapidly. Amphibians, as highly sensitive organisms, are excellent indicators of environmental change, yet quantitative assessments of their diversity in the Huangshan Mountains-a biodiversity hotspot at the junction of the Palaearctic and Oriental realms in southern Anhui, China-remain limited. We conducted systematic line-transect surveys across 200 grids (5 km x 5 km) during the spring and autumn of 2023 and 2024, recording a total of 10,342 individuals belonging to 23 species, 20 genera, 9 families, and 2 orders. Three species (Fejervarya multistriata, Microhyla fissipes, and Bufo gargarizans) were identified as dominant, and two nationally protected species (Hoplobatrachus chinensis and Andrias davidianus) were detected. Inter-annual alpha diversity did not differ significantly, but pronounced seasonal variation was observed, with spring supporting higher Shannon-Wiener and Pielou evenness than autumn in both years. Using generalized additive models and model averaging, we found that annual precipitation and the normalized difference vegetation index (NDVI) were consistently the strongest positive predictors of Shannon-Wiener diversity, Simpson dominance, and species richness, while species richness also declined significantly with increasing human footprint. Total beta diversity (Soerensen dissimilarity) was very high (0.981) and overwhelmingly driven by species turnover (97.86%) rather than nestedness. Partial Mantel tests and distance-based redundancy analysis further revealed that environmental distances-particularly annual precipitation-significantly shaped overall beta diversity and its turnover component after accounting for geographic distance. These results highlight the predominant role of climatic and vegetation gradients in structuring amphibian assemblages in this subtropical mountainous region, providing baseline data to inform local conservation strategies.

ecology↗

bioRxiv2026

In vitro and in silico characterization of competitive inhibition and repression of DUX4 target gene activation as a therapeutic approach for facioscapulohumeral muscular dystrophy (FSHD)

Facioscapulohumeral muscular dystrophy (FSHD) is a rare neuromuscular disease caused by aberrant re-expression of the embryonic transcription factor DUX4 in skeletal muscle, which activates a toxic transcriptional program that drives progressive muscle wasting. No disease-modifying therapies currently exist. Prior work in mammalian and zebrafish models has shown that a truncated form of DUX4 retaining only its DNA-binding domain (DBD) lacks transactivation capacity and can suppress DUX4-FL-driven pathology; separately, dCas9/KRAB-based epigenetic repressors have demonstrated efficacy in silencing DUX4 expression, though CRISPR-based strategies face challenges from the repetitive nature of the D4Z4 locus, the immunogenicity associated with bacterial Cas proteins, and the payload limitations of gene delivery vehicles. Building on these findings, we corroborate that the DUX4 DBD, comprising both homeodomains, acts as a non-toxic competitive inhibitor of full-length DUX4 (DUX4-FL) at its genomic target sites, and extend this strategy by fusing the DBD to a human KRAB(ZNF10) domain, converting DUX4 from a transcriptional activator into a fully humanized epigenetic silencer of its own targets. Using a fluorescent DUX4-responsive reporter, we show that DBD alone produces dose-dependent repression of DUX4-FL transcriptional activity in HEK293T cells (200-fold at the highest inducible dose tested), while a constitutively expressed DBD-KRAB fusion produces significantly greater repression than DBD alone (949-fold versus 17-fold at a 25x molar ratio), with a similar trend observed in C2C12 myoblasts (47-fold versus 3.3-fold knockdown). To contextualize these findings and explore dosing considerations, we developed three complementary computational models - a transcription factor competitive binding model, a myotube diffusion model, and an ordinary differential equation (ODE) compartmental model - that illustrate how DBD concentration, intracellular diffusion, and population-level cell state transitions may relate to therapeutic efficacy. Together, these results corroborate and extend existing approaches into a single, fully humanized construct that may help circumvent the immunogenicity and delivery limitations of Cas-based systems.

bioengineering↗

bioRxiv2026

CRTC, not phosphorylated CREB1, drives cAMP-induced transcription across diverse cell types

Specialized cell types layer cell-type-restricted proteins, metabolites, and organelles onto a shared foundation of core cellular processes. How this ubiquitous machinery generates lineage-specific outputs is central to both cell biology and therapeutic development. G-protein-coupled receptors (GPCRs) respond to receptor-restricted ligands to drive cell-type-specific transcription through cAMP-mediated activation of protein kinase A (PKA), which activates the transcription factor CREB1 through two parallel modes: direct phosphorylation at serine 133, and inhibition of salt-inducible kinases (SIK) that restrain the CRTC coactivators. How these modes integrate and contribute to signaling across cell types has remained unresolved, obscured by genetic redundancy and essentiality. Here we combine focused genetic analyses with a cross-lineage transcriptomic survey to dissect these parallel inputs. In Creb1/Atf1/Crem triple-knockout cells, a non-phosphorylatable mutant CREB1S133A fully rescued endogenous target gene activation, while Crtc1/Crtc2/Crtc3 ablation abolished transcription even with intact CREB1 serine 133 phosphorylation. As part of this mechanism, we found the annotated repressor ICER can instead act as a positive regulator, substituting for full-length CREB1 paralogs to drive a feedforward loop. Across melanocytes, hepatocytes, osteocytes, macrophages, and neurons, SIK inhibition recapitulated cAMP-PKA-driven transcription across both shared and cell-type-specific gene expression programs, with neurons a notable exception. These results invert the canonical model, placing CRTC recruitment as the dominant driver of CREB1-mediated transcription across diverse lineages, reframing how cAMP-PKA signaling can be interpreted and therapeutically targeted.

cell biology↗

bioRxiv2026

Impaired synthesis of both telomere strands and adaptive TERT reduction in RTEL1 ATPase-dead cells

Regulator of Telomere Elongation Helicase 1 (RTEL1) plays a critical role in telomere replication by disassembling DNA secondary structures such as G-quadruplexes and telomeric loops (T-loops). However, its precise mechanism remains unclear. Previously, we generated HeLa cells homozygous for ATPase-dead RTEL1. Here, we found that these cells have a 50-60% reduction in the synthesis of both telomere strands, indicating that RTEL1 ATPase activity is essential for both leading-strand and lagging-strand synthesis. Surprisingly, these cells also showed a substantial reduction in Telomerase Reverse Transcriptase (TERT) mRNA levels and a 60-80% reduction in telomerase activity, without activating alternative lengthening of telomeres (ALT). Forced TERT overexpression suppressed proliferation and caused late S/G2 accumulation, implying that the natural TERT reduction provides adaptive resistance. Expressing wild-type (WT) RTEL1 at levels close to physiological levels failed to rescue growth defects, suggesting a dominant-negative effect. These results reveal unexpected interactions between RTEL1 and telomerase and show how cancer cells compensate for RTEL1 dysfunction by decreasing TERT expression.

cell biology↗

bioRxiv2026

Circulating APOH promotes aortic dissection by activating the vascular smooth muscle cell NR5A1-PPARγ pathway.

IntroductionsAortic dissection (AD) is a life-threatening vascular disease with limited therapeutic targets. Apolipoprotein H (APOH), a circulating glycoprotein implicated in lipid metabolism, has not been studied in AD. MethodsPlasma APOH levels and aortic deposition were examined in AD patients. A {beta}-aminopropionitrile (BAPN) and angiotensin II (Ang-II)-induced mouse AD model with AAV-mediated Apoh knockdown was used to evaluate survival, aortic dilation, and extracellular matrix remodeling. Transcriptomic profiling, chromatin immunoprecipitation, and gene silencing in human aortic vascular smooth muscle cells (HAVSMC) were performed to dissect the mechanism. PPAR{gamma} agonist rescue was conducted in vivo. ResultsAPOH was elevated in plasma and deposited in AD aortas. Apoh knockdown improved survival, reduced AD incidence and ascending aortic dilation, and attenuated elastic fiber disruption and collagen deposition. Transcriptomics revealed enrichment of the PPAR pathway. APOH promoted HAVSMC phenotypic switching from a contractile to a synthetic state, decreasing ACTA2/TAGLN and increasing OPN/MMP9. Mechanistically, APOH upregulated NR5A1, which directly bound the PPAR{gamma} promoter to enhance PPAR{gamma} and FABP4 expression. Silencing NR5A1 or PPAR{gamma} reversed APOH-induced phenotypic switching and inflammation. In vivo, PPAR{gamma} agonist diminished the protective effects of Apoh silencing. ConclusionAPOH promotes AD progression through the NR5A1-PPAR{gamma} axis, driving vascular smooth muscle cell phenotypic switching and inflammation, and represents a potential therapeutic target. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=142 SRC="FIGDIR/small/739043v1_ufig1.gif" ALT="Figure 1"> View larger version (64K): org.highwire.dtl.DTLVardef@6c4196org.highwire.dtl.DTLVardef@145f5a2org.highwire.dtl.DTLVardef@19bdborg.highwire.dtl.DTLVardef@19f5019_HPS_FORMAT_FIGEXP M_FIG C_FIG Circulating APOH promotes aortic dissection through the NR5A1-PPAR{gamma} axis in human aortic vascular smooth muscle cells. Clinical observations showed that plasma APOH levels were elevated in patients with aortic dissection. Circulating APOH acts on human aortic vascular smooth muscle cells (HAVSMC) and upregulates NR5A1, which binds to the PPARG promoter and enhances PPAR{gamma} transcription. Activation of the NR5A1-PPAR{gamma} signaling axis promotes the phenotypic transition of HAVSMCs from a contractile phenotype to a synthetic phenotype, as indicated by decreased ACTA2 and TAGLN expression and increased OPN and MMP9 expression, accompanied by enhanced production of the inflammatory mediators IL-6, MCP-1, and TNF-. Silencing NR5A1 or PPAR{gamma} reverses APOH-induced phenotypic switching and inflammatory responses, supporting the critical role of the NR5A1-PPAR{gamma} axis in APOH-mediated vascular injury.

genomics↗

bioRxiv2026

EBD-DTI: Episodic Bridge Diffusion for Zero-Shot Cold-Start Drug-Target Interaction Prediction

Predicting drug-target interactions (DTI) for entirely unseen drugs or proteins--the cold-start problem--remains a critical challenge in computational drug discovery. While sequence-based methods naturally support zero-shot generalization, they often ignore relational topology, and existing graph-based approaches either rely on global diffusion that blurs the boundary between inductive and transductive evaluation or require a few known interaction samples at test time (few-shot). We present EBD-DTI, a framework that enables zero-shot inference in graph-based DTI models without requiring any known interactions for unseen entities. The key innovation is episodic cold-start training : at each epoch, a random subset of training entities is masked and treated as pseudo-cold, forcing the model to learn cold-start inference with explicit gradient supervision. A bridge-conditioned local subgraph, together with multi-hop diffusion, provides cold entities with relational context from their nearest observed neighbors. Experiments on three benchmarks (BioSNAP, BindingDB, and DrugBank) demonstrate that EBD-DTI achieves competitive or superior performance compared to state-of-the-art methods under strict zero-shot evaluation, with episodic training improving AUC by up to 12%.

bioinformatics↗

bioRxiv2026

Bovine-derived H5N1 influenza virus efficiently infects lactating swine via the mammary gland

Since 2024, highly pathogenic influenza A(H5N1) viruses have spread extensively among U.S. dairy cattle, where they replicate efficiently in the mammary gland and are shed at high titers in milk. To directly assess susceptibility of commercial swine populations to bovine-derived H5N1 virus, lactating sows with prior influenza virus vaccination histories representative of U.S. commercial swine production systems were inoculated via the intramammary route and co-housed with their 1-week-old piglets to evaluate disease outcomes, viral replication, and potential for vertical transmission. Intramammary inoculation of lactating sows resulted in sustained viral RNA shedding in milk, while piglets exhibited sporadic oral viral RNA positivity that mirrored viral kinetics in milk. Lesions in mammary tissue and viral antigen staining, as well as development of neutralizing antibody responses and changes in milk color and consistency, further confirmed infection in the sows. Despite these molecular findings, none of the animals developed overt clinical disease, and respiratory involvement was not noted during the study period. Collectively, we demonstrate that intramammary exposure results in productive influenza A(H5N1) virus infection in lactating sows despite their vaccination histories, indicating the potential threat of viral spillover into commercial swine populations. The clinically inapparent nature of infection presents a risk of subclinical spread and underscores the importance of expanding viral surveillance to swine.

microbiology↗

bioRxiv2026

A Minimally Invasiveness Hybrid Brain-Computer Interface: A Distributed, Scalable and Evolvable Architecture for Whole Brain Access

Brain-computer interfaces face a fundamental trade-off between the signal fidelity and stimulation precision of noninvasive systems and the surgical burden and scalability of invasive systems. Non-invasive BCIs suffer from low signal quality and poor stimulation accuracy due to the skull barrier and the variability introduced by the scalp and skull. Existing invasive BCIs rely on traumatic surgical procedures or brain-penetrating electrodes, which limits their spatial extensibility, application, and patient acceptance. Here, we introduce a minimally invasive hybrid BCI architecture that uses the skull as a distributed interface layer rather than treating it solely as a barrier. The hybrid BCI comprises four integrated components: (1) the safe and smart micro-hole craniotomy; (2) distributed microelectrodes subcutaneously implanted in micro-holes in the skull with the distal end in contact with the dura; (3) an external bi-directional wearable headset for coupling, recording, stimulation, and channel selection; and (4) an AI-assisted planning and control agent. Animal studies have shown that micro-holes with a diameter of 300-800 m can be safely and conveniently prepared at any predefined locations across the skull without impairing the dura. In vivo experiments on rats demonstrate that the hybrid BCI with skull-implanted microelectrodes evidently increases resting-state spectral power and improves the signal-to-noise ratio of somatosensory and steady-state visual evoked responses compared to the scalp EEG; the computational modelling shows that distributed skull-dura microelectrodes can increase the intracranial electrical field strength and steer focused temporal-interference fields towards predefined deep brain targets. These findings will lay a solid foundation for future endeavors in wireless integration, safety evaluation and clinical benefits of the hybrid BCI. In summary, we propose the hybrid BCI as a distinct minimally invasive BCI paradigm with the great potential as a distributed, scalable, and upgradable neural interface that can expand the clinical application of minimally invasive BCI techniques.

bioengineering↗

bioRxiv2026

IL-21-producing peripheral helper T cells associate with autoimmune bile duct injury in biliary atresia

BackgroundBiliary atresia (BA) is a severe neonatal liver disease characterized by progressive fibrosis and bile duct obliteration. ObjectiveAlthough immune dysregulation is implicated in the pathogenesis of BA, the specific mechanisms driving bile duct injury remain incompletely understood. This study aimed to characterize tertiary lymphoid structures (TLSs) within extrahepatic biliary remnants (EBRs), identify their cellular mediators, and evaluate the therapeutic potential of targeting IL-21 receptor signaling. DesignWe performed integrated bulk RNA sequencing, single-cell RNA sequencing, spatial transcriptomics, multiplex immunohistochemistry, and flow cytometry on clinical samples from BA patients and non-BA cholestatic controls. TLS maturation was assessed by CD23 immunohistochemistry in EBRs from 148 BA patients and correlated with clinical parameters. Anti-IL-21R antibody treatment was evaluated in a rhesus rotavirus-induced BA mouse model, with treatment initiated on day 4 post-infection. ResultsTLSs were identified in BA EBRs with significantly higher prevalence than in matched liver tissues. Mature TLSs containing CD23 germinal centers were associated with elevated serum matrix metalloproteinase-7, more advanced hepatic fibrosis, and localized autoantibody deposition on injured bile ducts. Single-cell profiling revealed expanded CD4+ T peripheral helper (Tph) cells expressing IL-21 and CXCL13 within TLS-containing EBRs. Tph cells were enriched in peripheral blood of BA patients compared to non-BA cholestatic controls (P = 0.0025), and serum IL-21 was significantly elevated (P < 0.0001). Post-infection IL-21R blockade in the mouse model reduced jaundice incidence, improved weight gain, prevented extrahepatic biliary obstruction, and significantly improved long-term survival. ConclusionTLSs in BA extrahepatic biliary remnants harbor expanded Tph cells associated with IL-21-mediated B cell activation and bile duct injury. IL-21R blockade ameliorated disease in a murine BA model, identifying the IL-21/IL-21R axis as a potential therapeutic target warranting further investigation. Key MessagesO_ST_ABSWhat is already known on this topicC_ST_ABSImmune dysregulation contributes to biliary atresia (BA), with documented lymphocyte infiltration and defective B cell tolerance. However, the cellular mechanisms linking local immune activation to bile duct injury are unclear, and the roles of organized lymphoid structures and specific CD4 T cell subsets in orchestrating local humoral responses have not been characterized. What this study addsThis study demonstrates that mature tertiary lymphoid structures in extrahepatic biliary remnants are associated with disease severity markers and localized bile duct injury in BA. We identify T peripheral helper cells as an expanded IL-21-producing CD4 T cell population within these structures, and show that post-infection IL-21 receptor blockade prevents biliary obstruction and improves survival in a murine BA model. How this study might affect research, practice or policyThese findings identify the IL-21/IL-21R signaling axis as a candidate therapeutic target in BA warranting further preclinical and translational investigation. TLS maturation status in biliary remnants and serum autoantibody levels may serve as potential biomarkers of disease severity, meriting prospective evaluation in clinical cohorts.

immunology↗

bioRxiv2026

Recognition Mechanism of Serotonin by a G-Quadruplex-Duplex Hybrid Aptamer

Serotonin is a key neurotransmitter, and aptamer-based tools using the 44-nt Apt44 have been successfully developed for its in vitro and in vivo detection. Nevertheless, the structural basis of recognition by this aptamer remains unclear. Here we report high-resolution NMR structures of Apt38, a 6-nt truncated variant in the third loop of Apt44, in free and serotonin-bound states. Both structures reveal a two-layered antiparallel chair-type G-quadruplex core with three edgewise loops and a terminal duplex, forming a G-quadruplex-duplex hybrid structure. Serotonin binds at the G-quadruplex-duplex junction, stabilized by stacking, electrostatic attraction, hydrogen bonding, and hydrophobic contacts. Apt38 is preorganized for binding, whereas the longer third loop of Apt44 introduces conformational dynamics into the G-quadruplex scaffold, which enables a pronounced binding-triggered conformational switch in PBS buffer, explaining its sensing mechanism. Our work reveals the recognition and sensing mechanism of the serotonin aptamer and provides a framework for aptamer design in serotonin biosensing.

biophysics↗

bioRxiv2026

Sequential infection reprograms the immune landscape to shape future responses

Mouse models have been instrumental in defining immune mechanisms but often fail to capture the complexity of human immunity, limiting clinical translation. A major limitation is the immunological immaturity of specific pathogen-free (SPF) mice relative to pathogen-experienced adult humans. Here, we use a sequential infection (SI) model that recapitulates cumulative pathogen exposure and define its impact on immune composition and function. Beyond the previously reported expansion of memory T cells, SI induced durable, system-wide remodeling across lymphoid and non-lymphoid tissues, reshaping innate and adaptive immune populations, tissue-resident immunity, and hematopoietic output. Single-cell transcriptomic analyses revealed inflammatory imprinting of naive CD4 and CD8 T cells, whereas memory T cells acquired enhanced effector programs coupled with reduced biosynthetic activity, transcriptional states that more closely resemble those of pathogen-experienced adult humans. Functionally, SI mice recapitulated the human response to anti-CD28 super-agonist and exhibited altered magnitude and differentiation of acute and chronic antiviral T cell responses, demonstrating that cumulative pathogen exposure reshapes both existing immunity and the generation of future immune responses. Thus, cumulative pathogen exposure coordinately remodels hematopoiesis and naive and memory lymphocyte states, establishing a durable inflammation-experienced immune landscape that reshapes both immune memory and future immune responses, with broad implications for the translational fidelity of preclinical mouse models.

immunology↗

bioRxiv2026

Brain Structure Shapes Function through higher-order Functional Interactions

Brain function is deeply embedded within multiscale structural architecture. Conventional studies predominantly utilize pairwise connectivity networks to investigate structure-function relationships. However, this low-dimensional perspective overlooks multi-region collaborations for complex cognition. Consequently, whether and how anatomy constrains such higher-order functional networks remains unresolved. To address this pivotal question, we utilize an information-theoretic O-information approach to characterize higher-order functional interactions (HOIs). By reconstructing individual-level HOIs from multimodal structural networks, we directly validate the structural constraint on HOIs. The resulting reconstruction coefficients are defined as structural-functional constraint strength (SFCS), serving as a quantitative vehicle to decipher how anatomy shapes these higher-order networks. SFCS uncovers a highly heterogeneous structural constraint landscape across data modalities, spatial regions, and informational interaction modes. Crucially, individualized SFCS robustly predicts multi-domain cognitive phenotypes, showing higher sensitivity for informant-reported than patient-reported assessments. Finally, we show that this landscape undergoes pathological, mode-specific reorganization in Alzheimers disease. Cross-scale alignment with spatial transcriptomics further demonstrates that this macroscale network remodeling is coupled with microscale metabolic and regulatory gene pathways. Collectively, our findings not only validate the structural constraint on higher-order functional networks but also decipher its precise underlying mechanisms. This constraint paradigm plays a pivotal role in shaping diverse cognitive capabilities, while its pathological disruption in Alzheimers disease highlights the potential of SFCS as a biomarker for tracking neurodegenerative network impairments.

neuroscience↗

bioRxiv2026

Intracellular barriers and receptor masking limit success of a Pseudomonas aeruginosa clinical phage family

Bacteriophage therapy is needed to treat antibiotic resistant infections; however, when a clinical isolate resists a given phage, it is often unclear why. It is therefore currently unknown how to rationally fortify phage therapies to circumvent a priori resistance. Using a family of broad host range therapeutic Pseudomonas aeruginosa phages (Pbunaviruses), we show that cell surface receptor masking and intracellular defenses are both common barriers in distinct clinical isolates. In some cases these barriers can be bypassed by intrafamily phage engineering. Using unbiased genome-wide CRISPRi screens, we reveal that the broadly conserved L-Rhamnose in the core polysaccharide is the receptor for Pbunavirus family. This molecule is often masked by diverse O-antigen structures. In other isolates with the L-Rha receptor accessible, internal defense mechanisms commonly prevent Pbunavirus DNA replication. A single anti-defense locus often encoding 8-11 different genes within the Pbunavirus family is required for optimal host range, providing anti-defense genes that enable replication of both Pbunavirus phages and phages of other families. Our work demonstrates the importance of both internal and surface defense mechanisms in clinical isolates causally antagonizing a commonly used phage therapeutic and presents phage engineering strategies to circumvent a priori resistance.

microbiology↗

bioRxiv2026

scIsoAgent enables autonomous isoform-resolved characterization and sequence-informed interpretation of long-read single-cell transcriptomes

Alternative isoform usage can alter gene function independently of total gene expression, creating a need to resolve transcript isoforms at single-cell resolution. Long-read single-cell RNA sequencing meets this need by linking cellular identity to transcript isoforms and sequence-level features. Realizing its full biological value requires reproducible workflows that connect specialized long-read analysis with biological interpretation. Existing large language model (LLM)-based biomedical agents support general omics analysis, but are not designed for isoform-resolved long-read single-cell workflows. Here, we present scIsoAgent, an autonomous LLM-powered scientific agent for long-read single-cell RNA-seq analysis. scIsoAgent turns heterogeneous long-read single-cell inputs into traceable isoform-resolved workflows, using stage-aware planning and persistent computational context to support both execution and interpretation. Across complementary evaluations, this design improved the continuity from analysis planning to executable, interactive workflows compared with general-purpose LLM baselines. In real-data reanalysis, scIsoAgent recovered major findings from published long-read single-cell resources and extended a representative differential transcript usage event into a sequence-informed functional hypothesis. By linking full-length isoform sequences with model-inferred transcript properties, scIsoAgent connects observed isoform usage with potential sequence-level functional consequences. These results demonstrate that autonomous scientific agents can transform fragmented long-read single-cell analysis into coherent, reproducible workflows for isoform-resolved discovery and biological interpretation.

bioinformatics↗

bioRxiv2026

TAp63-regulated oncogenic long non-coding RNA-8 ( TROLL-8 ) regulates human breast cancer progression through CPT1A-mediated fatty acid oxidation

Metabolic reprogramming is a crucial hallmark of cancer, supporting tumor growth and adaptation to cellular stress. Although fatty acid oxidation (FAO) has emerged as an important regulator in cancer, the mechanisms that control the FAO machinery remain poorly understood. Here, we demonstrate that the TAp63-regulated long non-coding RNA TROLL-8 is a key regulator of FAO in breast cancer. Using metabolomics and protein microarray assays followed by immunoprecipitation-mass spectrometry, we mechanistically demonstrate that TROLL-8 binds the FAO enzyme CPT1A and promotes the formation of a complex with ACSL1 and VDAC1, thereby enabling efficient fatty acid processing. Loss of TROLL-8 destabilizes this complex, leading to impaired FAO, decreased metabolic fitness, and suppression of tumorigenic phenotypes, such as anchorage-independent growth. Notably, higher levels of CPT1A and VDAC1 are associated with worse survival in breast cancer patients. Given the emerging role of CPT1A in therapy resistance, these findings suggest that targeting TROLL-8 could be a promising approach to selectively disrupt the hyperactive FAO machinery in breast cancers and other tumor types that rely on FAO for their progression.

Cancer Biology↗

bioRxiv2026

Cardiomyocytes Undergo a Mesenchymal-Like Fate Transition in Myocardial Fibrosis

BACKGROUNDMyocardial fibrosis, a pathological hallmark of adverse cardiac remodeling and heart failure, has been conventionally attributed to the activation of resident fibroblasts. Although recent studies suggest contributions from non-fibroblast lineages, direct in vivo genetic evidence that cardiomyocytes can undergo a mesenchymal-like fate transition during myocardial fibrosis remains absent. This study aims to investigate whether such a transition occurs and to elucidate the underlying regulatory mechanisms. METHODSHuman myocardial infarction (MI) tissues were analyzed by immunohistochemistry and integrated with public single-nucleus RNA sequencing (snRNA-seq) data to detect mesenchymal-like signatures in cardiomyocytes. Genetic lineage-tracing was performed in MI mice, and in cardiomyocyte-specific Hgs (hepatocyte growth factor-regulated tyrosine kinase substrate) gene knockout mice, to map the fate of cardiomyocyte-derived cells. Mechanistic insights were obtained through proteomic and snRNA-seq analysis of Hgs knockout hearts and validated through gain- and loss-of-function experiments targeting Aldh1a2 (aldehyde dehydrogenase 1 family member A2). RESULTSIn human MI samples, a subset of cardiomyocytes showed reduced expression of cardiomyocyte markers concurrent with acquisition of mesenchymal-associated markers. Genetic lineage tracing demonstrated that adult cardiomyocytes can adopt a mesenchymal-like cell fate during post-MI remodeling. We identify HGS as a factor constraining this transition. Hgs knockout in adult cardiomyocytes upregulated Aldh1a2, triggered the mesenchymal-like fate transition, and gave rise to cells expressing markers of activated fibroblasts or osteoblasts, accompanied by pronounced myocardial fibrosis and calcification. Forced Aldh1a2 overexpression in cardiomyocytes drove the mesenchymal-like fate transition in vitro and in vivo, whereas Aldh1a2 deletion in cardiomyocytes mitigated MI-induced myocardial fibrosis. CONCLUSIONSThis study provides in vivo genetic evidence that adult cardiomyocytes possess the capacity to undergo a mesenchymal-like fate transition under pathological conditions. Our data suggest that HGS and ALDH1A2 serve as regulators of the transition, offering a new basis for understanding cellular and molecular mechanisms of myocardial fibrosis. Novelty and SignificanceO_ST_ABSWhat Is Known?C_ST_ABSO_LIMyocardial fibrosis is primarily driven by resident fibroblast activation, with additional contributions from cardiac CD34+ cells, pericytes, and macrophages. C_LIO_LIAdult cardiomyocytes exhibit phenotypic plasticity and transdifferentiate into epicardial-like or pacemaker cells under specific conditions. C_LI What New Information Does This Article Contribute?O_LIA subset of cardiomyocytes adopts a mesenchymal-like cell fate during myocardial fibrosis, marked by downregulation of cardiomyocyte identity markers and loss of aligned cell-cell contacts. C_LIO_LIThese cells acquire mesenchymal morphology and markers, ECM components, migratory gene signatures, and proliferative capacity. C_LIO_LIHGS and ALDH1A2 act as regulators of this mesenchymal-like fate transition. C_LI Myocardial fibrosis drives heart failure progression, yet the cellular sources of pathological fibroblasts remain incompletely defined. Here, we demonstrate that a subset of cardiomyocytes adopts a mesenchymal-like cell fate during myocardial fibrosis by using an integrated approach combining human MI samples, murine genetic lineage tracing, and snRNA-seq. Mechanistically, we identify HGS and ALDH1A2 as regulators of this transition. Cardiomyocyte-specific Hgs deletion upregulates Aldh1a2, triggering the mesenchymal-like fate transition. Furthermore, Aldh1a2 overexpression drives this transition, while its deletion attenuates MI-induced fibrosis. These findings reveal a previously unrecognized plasticity of adult cardiomyocytes and identify potential therapeutic targets for fibrotic heart disease.

genetics↗