Biology subjects

Luo, Y.

Publications and source records attributed to Luo, Y..

At least 55 records · Page 3Linked to original sources

bioRxiv2026

IFITM1 inhibits Henipavirus membrane fusion by trapping ephrinB2 receptors in fusion-unfavorable membrane nanodomains.

Nipah (NiV) and Hendra (HeV) viruses are prototype henipaviruses (HNV) within the family of Paramyxoviridae. They are highly pathogenic zoonotic paramyxoviruses that cause fatal encephalitis in humans, with case fatality rates of 40-70%. These viruses use the receptor-binding protein (G) to engage host receptors ephrinB2 and/or ephrinB3, while the fusion protein (F) drives membrane fusion leading to virus entry and cell-cell fusion. Interferon-inducible transmembrane (IFITM) proteins restrict the infection of many unrelated viruses at virus entry. We show that the knockdown of IFITM1 enhances HNV entry and cell-cell fusion in both human epithelial and endothelial cells, while overexpression of IFITM1 inhibits both. Using single-molecule localization microscopy, we observed that IFITM1 forms nanoclusters on the plasma membrane that are enhanced upon interferon stimulation. IFITM1 clusters spatially co-occur with GM1-enriched, raft-like membrane domains. Notably, IFITM1 interacts with ephrinB2, and redistributes ephrinB2 into larger and denser clusters, potentially within GM1-enriched regions. Using single-particle tracking, we further show that ephrinB2s lateral diffusion on the plasma membrane is confined by IFITM1, and this confinement is not reversed by amphotericin B, a membrane-permeabilizing agent that increases membrane fluidity. Our data suggest that IFITM1 sequesters ephrinB2 in fusion-unfavorable membrane domains, thereby enhancing the energy barrier for virus-cell membrane fusion and decreasing the virus-receptor encounters. SignificanceNipah (NiV) and Hendra (HeV) viruses are zoonotic paramyxoviruses that cause fatal encephalitis in humans. Here, we show that IFITM1 inhibits NiV and HeV entry at the surface of epithelial and endothelial cells. We report that IFITM1 restricts NiV entry by sequestering the host receptor ephrinB2 in membrane domains that are energetically unfavorable for virus-cell membrane fusion. IFITM1 also restricts ephrinB2 lateral diffusion on the plasma membrane, thereby reducing productive virus-receptor encounters. Notably, amphotericin B treatment, which increases membrane fluidity, did not rescue IFITM1-mediated confinement of ephrinB2 or restore NiV entry. Our data reveal a new mechanism by which IFITM1 restricts NiV infection, suggesting that its antiviral activity extends beyond simply altering membrane fluidity.

microbiology↗

bioRxiv2026

Reconstructing True 3D Spatial Omics at Single-Cell Resolution

Capturing the three-dimensional (3D) organization of cells is essential for deciphering complex biological processes, yet comprehensive 3D spatial omics is severely hindered by the destructive nature of physical sectioning and the depth limitations of intact tissue imaging. Current computational methods rely on 2.5D stacking of discrete slices, which inherently disrupts tissue topology and fails to resolve continuous depth-dependent molecular gradients. To bridge this gap, we introduce DO_SCPLOWEEPC_SCPLOWSO_SCPLOWPATIALC_SCPLOW, an Optimal Transport flow matching framework that models tissue evolution as a continuous dynamic vector field. By solving the underlying probability flow ODEs, DO_SCPLOWEEPC_SCPLOWSO_SCPLOWPATIALC_SCPLOW enables the direct extraction of uninterrupted, infinitely resolvable tissue states at arbitrary spatial depths. Using Deep STAR/RIBOmap 3D technologies, we demonstrate that DO_SCPLOWEEPC_SCPLOWSO_SCPLOWPATIALC_SCPLOW achieves improved 3D reconstruction fidelity relative to 2.5D approaches, yielding structures that more closely recapitulate native tissue microenvironments in real-world datasets. Across diverse spatial omics modalities, including spatial proteomics using imaging mass cytometry in human breast cancer and spatial transcriptomics using openST in head and neck squamous cell carcinoma metastatic lymph nodes, DO_SCPLOWEEPC_SCPLOWSO_SCPLOWPATIALC_SCPLOW produces biologically interpretable and high-fidelity reconstructions across datasets. We evaluated the scalability and robustness of DO_SCPLOWEEPC_SCPLOWSO_SCPLOWPATIALC_SCPLOW on a large-scale mouse brain dataset, reconstructing a continuous 3D cellular atlas comprising 39 million cells within 41.6 hours. Systematic downstream characterization validated its ability to recapitulate consistent spatial architectures, cell-type distributions, transcriptomic patterns, and microenvironmental structures across brain regions. Collectively, these results demonstrate DO_SCPLOWEEPC_SCPLOWSO_SCPLOWPATIALC_SCPLOW as a generalizable and efficient solution for true 3D spatial reconstruction across scales and modalities. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=117 SRC="FIGDIR/small/721395v2_ufig1.gif" ALT="Figure 1"> View larger version (49K): org.highwire.dtl.DTLVardef@1a19624org.highwire.dtl.DTLVardef@188361forg.highwire.dtl.DTLVardef@199321corg.highwire.dtl.DTLVardef@a8f411_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioinformatics↗

bioRxiv2026

Identification of AAV Capsids with Enhanced Intravitreal Transduction and Favorable Safety Profile in Non-Human Primates

We report the discovery of novel adeno-associated virus (AAV) capsid variants engineered for superior intravitreal (IVT) gene delivery to the primate retina. Utilizing the REACH platform, we constructed a diverse AAV variant library and employed a multi-stage screening strategy involving in vitro selection on human retinal pigment cells followed by direct in vivo screening in non-human primates (NHPs). Following IVT administration in NHPS of a barcoded variant pool, next-generation sequencing analysis of retinal tissues identified lead candidates (e.g., E52, E54, and E57) that achieved transduction levels in the neural retina and RPE 5-10 fold higher than the benchmark R100. Concurrently, these high-potency variants exhibited an exceptional ocular confinement profile, with minimal to undetectable vector genome distribution in systemic organs. This combination of markedly enhanced retinal transduction and stringent local tropism establishes these engineered capsids as promising next-generation vectors for the treatment of inherited and acquired retinal diseases via a minimally invasive IVT route.

bioengineering↗

bioRxiv2026

Three-dimensional Virtual Adult Cardiomyocyte Transcriptomics

Obtaining transcriptomes of adult cardiomyocytes at single-cell resolution remains challenging due to their large size, elongated morphology, and frequent multinucleation. Although spatial transcriptomics preserves tissue architecture and captures gene expression in situ, current analytical frameworks largely rely on nuclear-based segmentation and are therefore poorly suited to adult cardiomyocytes. Furthermore, individual tissue sections capture only a fraction of a cardiomyocyte, preventing reconstruction of complete cell-level transcriptomes. Here we present three-dimensional virtual cardiomyocyte (3D-VirtualCM), a membrane-guided framework that integrates cell-contour similarity and optimal transport to reconstruct volumetric cardiomyocyte transcriptomes from consecutive spatial transcriptomic sections. Applying 3D-VirtualCM to infarcted adult mouse hearts, we generated a panoramic transcriptomic atlas spanning 100 m thickness at single-cell resolution. 3D-VirtualCM identified spatially and transcriptionally distinct cardiomyocyte populations within the infarct border zone, enabled high-throughput quantification of cardiomyocytes re-entering the cell cycle together with their associated molecular signatures, and revealed heterogeneous RNA distribution along the longitudinal axis of individual cardiomyocytes. By integrating three-dimensional cellular morphology with in situ transcriptomic data, 3D-VirtualCM provides a scalable approach for resolving cardiomyocyte states and spatial organization in physiological and pathological cardiac remodeling.

bioinformatics↗

bioRxiv2026

Benchmarking MSA pairing for protein-protein complex structure prediction reveals a depth-over-pairing principle

AlphaFold-Multimer (AFM) and AlphaFold3 (AF3) have revolutionized protein-protein complex structure prediction. However, it remains unclear whether elaborate MSA pairing is a strict prerequisite for achieving high accuracy. Here, we systematically evaluated diverse MSA construction strategies using a rigorous benchmark of 439 heterodimers. We found that incorporating paired MSAs yields only marginal improvements in structure prediction. Crucially, experiments using shuffled pairing patterns reveal that these gains stem not from specific pairing constraints, but rather from the increased depth of input MSAs, a finding that also extends to higher-order multimers. Furthermore, we demonstrate that prioritizing the inclusion of more homologs without pairing proves to be a superior strategy, enhancing performance for both intra- and inter-species dimers as well as the more challenging antibody-antigen complexes. This observation is substantiated by the recent success of the omicMSA strategy. Mechanistic analysis indicates that this capability is driven by inter-subunit physicochemical complementarity and the intrinsic architecture of the AF3 network. Furthermore, we identify critical bottlenecks that limit prediction accuracy, including large complex dimensions, restricted interface areas, and low experimental resolution. These findings establish a "depth-over-pairing" principle, offering new insights for improving protein complex prediction.

bioinformatics↗

bioRxiv2026

An EEG-fMRI Jointly Constrained Digital Twin Brain and Its Application in Alzheime's Disease

Current digital twin brain (DTB) models are typically optimized using single-modality functional neuroimaging data, which restricts their ability to simulate brain dynamics across multiple spatiotemporal scales. Here, we bridged this gap by developing a two-stage DTB (TS-DTB) modeling framework jointly constrained by functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) data. Validation in both the healthy young and Alzheimers disease (AD) cohorts demonstrated that the TS-DTB model simultaneously captures subject-specific features of multi-scale brain dynamics. In particular, the TS-DTB models of AD patients successfully recapitulated spectral-temporal signatures of cognitive decline, mechanistically linking these deficits to excitation-inhibition (E-I) imbalances. By simulating responses to repetitive transcranial magnetic stimulation (rTMS), we further revealed that cognitive recovery in AD patients can be driven by E-I rebalancing via synaptic reconfiguration and background suppression. Overall, these findings underscore the potential of the TS-DTB to advance the mechanistic understanding of the brain and inform personalized digital therapeutics.

neuroscience↗

bioRxiv2026

A trans-piRNA network and transcriptional antagonism shape piRNA cluster function

PIWI-interacting (pi)RNAs protect animal germlines from transposable elements (TEs) by guiding their sequence-specific repression. In Drosophila germline, piRNAs are encoded in distinct genomic regions, piRNA clusters (piCs), that are transcribed by a non-canonical machinery that is anchored on chromatin by the HP1 paralogue Rhino. Studies of transgenic piCs revealed that piRNA biogenesis depends on cytoplasmic inheritance of piRNAs, however, whether native piCs require trans-generational piRNA transmission remained unknown. Here, we used two approaches to show that cytoplasmic inheritance of cognate piRNAs is critical for piRNA biogenesis. Our analyses reveal that individual piCs form a tightly interconnected network linked by trans-acting piRNAs that reinforce biogenesis. According to the transposon trap model, the content of piCs is updated by integration of novel TEs leading to production of piRNA guides against integrated transposons. However, we found that transcription driven by promoters integrated into piCs disrupt local piRNA biogenesis by removing Rhino and antagonizing non-canonical transcription of piRNA precursors. Thus, newly inserted transposons might suppress piRNA production before they become domesticated by the piRNA pathway calling for a revision of the trap model. Together, our results reveal that piC activity is shaped by transcriptional competition and a dynamic interplay between individual piCs connected into a common network. HighlightsO_LICytoplasmic inheritance of maternal piRNAs is required for piRNA biogenesis in the next generation C_LIO_LITrans-acting piRNA ensure robustness of piRNA biogenesis and repression by connecting individual clusters into a functional network C_LIO_LIPing-pong amplification provides non-uniform processing of different regions inside piCs C_LIO_LIGenes can remain active inside piRNA clusters antagonizing Rhino-dependent non-canonical transcription and piRNA biogenesis, challenging the transposon trap model C_LI

molecular biology↗

bioRxiv2026

Shared and distinct oscillatory fingerprints underlying episodic memory and word retrieval

Both episodic memory and word retrieval have been linked to power decreases in the alpha and beta oscillatory bands, but these patterns have rarely been related to each other, partly due to a lack of methodological approaches available. In this explorative study, we investigate the similarities and dissimilarities in the oscillatory fingerprints of the retrieval of words and episodes by directly comparing the activity patterns across time, frequency, and space. We acquired electroencephalography (EEG) data of participants performing a language and an episodic memory task based on the same stimulus material. With a newly developed approach, we directly compared the source-reconstructed oscillatory activity using mutual information and a feature-impact analysis. While left temporal and frontal regions showed dissimilarities between the tasks, right-hemispheric parietal regions exhibited similarities. We speculate that this could indicate a homologous function of these regions, potentially sharing less-specific representations between the tasks. We further uncovered a dissociation of the alpha and beta bands regarding the similarity across tasks. While the beta band was dissimilar between word and episodic memory retrieval, the alpha band seemed to contribute to the similarity we observed in right parietal regions. Whether this points to a task-unspecific function of the alpha band or a functional role in the retrieval process of the presumed representations, remains to be determined. In summary, we present an approach to study similarity across tasks using the temporal, spectral, and spatial dimensions of EEG data, and present results of exploring the shared oscillatory fingerprints between episodic memory and word retrieval.

neuroscience↗

bioRxiv2026

The structure-interaction model of polymyxin lipopeptides with human oligopeptide transporter 2

Multidrug-resistant (MDR) Gram-negative bacteria pose a critical global health threat, while polymyxins remain a last-line therapy. However, their clinical use is limited by nephrotoxicity. Human oligopeptide transporter 2 (hPepT2) is a membrane transporter mediating the reabsorption of polymyxins in renal cells and contributes to their nephrotoxicity, but the molecular basis of their interaction remains unclear. Here, we investigated the structure-interaction relationship (SIR) of polymyxins with hPepT2 by integrating computational, chemical, and cell biology approaches. Bioinformatic modelling predicted an outward-facing hPepT2 structure and a potential transport pathway, with polymyxins interacting at the lateral opening, particularly E214, D215, D317, D342, and E622. Transporter mutagenesis and molecular analyses confirmed that D215 is critical for polymyxin binding, while other residues influence transporter turnover and/or expression. We subsequently synthesised polymyxin analogues with modifications at Dab1, Dab3, Dab5, and Dab9 of polymyxins, which reduced interactions with hPepT2. Notably, alanine substitution at Dab3 reduced nephrotoxicity in mice while retaining antibacterial activity. Overall, this proof-of-concept study demonstrates that the hPepT2-polymyxin SIR model provides a viable strategy for developing novel, safer lipopeptide antibiotics.

biochemistry↗

bioRxiv2026

Novel Engineered AAV Variants Demonstrate Superior Blood-Brain Barrier Penetration and Safety in Non-Human Primates

Systemic delivery of adeno-associated virus (AAV) for gene therapy of central nervous system (CNS) disorders is limited by inefficient blood-brain barrier (BBB) penetration and dose-limiting toxicity in peripheral organs, notably the liver and dorsal root ganglia (DRG)1-5. Here, we report the development of novel AAV variants via a proprietary capsid engineering platform (REACH). In non-human primates (NHPs), intravenous administration of lead variants resulted in transgene expression levels in the brain that were 600-2000 fold higher than AAV9 at the RNA level, concomitant with a 10-50 fold reduction in liver tropism and minimal off-target exposure in the heart and DRG. These engineered capsids achieve unprecedented, pan-CNS transduction with a markedly improved safety profile, representing a transformative platform for treating a broad spectrum of neurological diseases.

neuroscience↗

bioRxiv2026

Genetic and adenoviral ablation of the choroid plexus reduces postnatal hippocampal neurogenesis

BackgroundChoroid plexus (ChP) produces cerebrospinal fluid (CSF) and regulates brain development and adult subventricular zone (SVZ) neurogenesis, but its role in postnatal hippocampal subgranular zone (SGZ) neurogenesis is not well understood. Neonatal hydrocephalus, a devastating neurological condition characterized by excessive accumulation of CSF in the brain, is sometimes treated in conjunction with partial ChP cauterization in the lateral ventricles, which results in the resolution of clinical symptoms without large reductions in ventricular volumes. To both understand the roles of the ChP/CSF system in normal CNS function and the impact of ChP ablation or cauterization in hydrocephalus, novel tools for the manipulation of CSF volume and production by ChP are urgently needed. MethodsWe first discovered specific "leaky" expression of diphtheria toxin receptors (DTR) in the ChP of adult ROSA26-iDTR mice, which resulted in a robust and permanent ablation of ChP and reduction of ventricular CSF volume after diphtheria toxin (Dtx) administration. In this study, we first tested the effectiveness of this genetic approach for ChP ablation at neonatal ages. We then generated a novel AAV5-CMV-DTR vector with high ChP tropism to more effectively reduce ventricular volume in these neonatal mice. Genetic (ROSA26-iDTR) and gene therapy (AAV5-DTR) approaches were compared for their extent of ChP ablation, reduction of ventricular CSF volume as assessed by MRI, and impact on postnatal hippocampal neurogenesis at neonatal and young adult ages. Lastly, we tested the therapeutic potential of AAV-mediated ChP ablation using an intracisternal kaolin model of hydrocephalus. ResultsIn our genetic model, ChP ablation and CSF volume reduction was robust at postnatal day (P)10-12, but ineffective at P3-5 with standard Dtx dosing (20 ng/g/day for 3 consecutive days). A higher dose of Dtx (40 ng/g/day) at P3-5 generated a mild reduction of CSF volume but was associated with higher subsequent neonatal mortality. In contrast, AAV5 CMV-DTR virus shows high tropism for ChP epithelial cells and leads to near-complete loss of ventricular CSF in neonates. ChP/CSF loss in neonates or young adult mice leads to a substantial reduction of DCX+ cells within the SVZ, but only a moderate reduction of DCX+ neuroblasts in the SGZ, without altering the number of proliferating or apoptotic cells. In the cisternal kaolin model of hydrocephalus, AAV-mediated ChP ablation within 10 hrs after the onset of hydrocephalus profoundly reduced parenchymal edema and corpus callosum hyperintensity without causing ventricular collapse. ConclusionsThis study reports a novel role of the ChP/CSF in maintaining the neuroblast pool in the neurogenic niches in both early postnatal and adult stages. ROSA26-iDTR-mediated ChP ablation is inefficient before P10, suggesting that this mouse line may be of limited utility in the early postnatal period. In contrast, our novel AAV vector efficiently targets the ChP and CSF production at both neonatal and adult ages, and demonstrates the therapeutic potential of AAV-mediated ChP ablation for the treatment of hydrocephalus. The limited radiographic changes in the kaolin mouse model mirror the clinical findings following choroid plexus cauterization in humans.

neuroscience↗

bioRxiv2026

Effect of dietary Chitosan supplementation on Intestinal Barrier Function and Growth Performance in weaned piglets challenged by Enterohemorrhagic haemolytic Escherichia coli

Enterohemorrhagic Escherichia coli O157:H7 (EHEC) is an important zoonotic pathogen that disrupts intestinal epithelial barrier integrity and induces excessive inflammatory responses, thereby leading to impaired growth performance and intestinal injury. EHEC is also an important cause Hemolytic Uremic Syndrome (HUS) in children and older adults. In pig production, chitosan is considered a promising alternative to antibiotics due to its bioadhesive and antimicrobial properties, but the effects and underlying mechanisms of chitosan (COS) under pathogenic challenge remain to be elucidated. One hundred and eight pigs were randomly divided into three treatments: an unchallenged control group (CON), an EHEC-challenged control group (ECON), and an EHEC-challenged group supplemented with 100 mg/kg COS (ECOS). Results show that EHEC challenge increased the feed conversion ratio (FCR), increased inflammatory cytokine levels, disrupted intestinal morphology, and downregulated tight junction and nutrient transporter gene expression (P<0.05). Dietary COS supplementation significantly improved average daily gain (ADG) and FCR during day 6-14 (P<0.05). Moreover, COS reduced fecal shedding of total E. coli (P = 0.085) and EHEC, attenuated systemic inflammation by decreasing serum TNF- and IL-6 levels, and enhanced humoral immunity as indicated by increased IgA and IgM concentrations (P<0.05). Importantly, COS alleviated EHEC-induced intestinal injury by restoring villus height and villus-to-crypt ratio, with enhanced mucosal digestive enzyme activities, and upregulated expression of tight junction proteins (ZO-1 and occludin) and nutrient transporters (SGLT-1 and PEPT1) (P<0.05). In conclusion, these findings indicate that dietary COS improves growth performance in EHEC-challenged weaned pigs, with enhanced intestinal barrier integrity and nutrient transport capacity.

microbiology↗

bioRxiv2026

LRP6-Guided Engineering of AAV9 Variants with Enhanced Blood-Brain Barrier Penetration and Reduced Liver Tropism in Non-Human Primates

The blood-brain barrier (BBB) severely restricts the delivery of systemically administered adeno-associated virus (AAV) vectors for central nervous system (CNS) gene therapy. To overcome this limitation, we engineered a library of AAV9 capsid variants through rational design focused on the low-density lipoprotein receptor-related protein 6 (LRP6), a conserved mediator of transcytosis. A multi-tiered screening strategy, encompassing human BBB endothelial cells followed by neuronal and glial target cells in vitro, identified three lead variants (QL9-21, QL9-22, and QL9-25) with markedly enhanced transduction potential. In mice, these variants achieved a 5-28 fold increase in brain-wide gene delivery compared to AAV9, without elevating hepatic tropism. Crucially, evaluation in non-human primates (NHPs) revealed that the lead variant, QL9-21, mediated a striking 3-40 fold enhancement in viral genome delivery across all examined brain regions versus AAV9, while concurrently reducing liver accumulation by 2.6 fold. Our study establishes an LRP6-guided engineering platform that yields novel AAV9 vectors capable of efficient, species-conserved BBB penetration coupled with a favorable safety profile, representing a significant advance toward clinically translatable CNS gene therapies.

neuroscience↗

bioRxiv2026

Microencapsulation of a novel Bacteroides thetaiotaomicron strain: a promising strategy to fortify intestinal barrier fortification in weaned pig model

Porcine Bacteroides thetaiotaomicron LYH5 demonstrated in vitro antimicrobial activity, suggesting probiotic potential. Due to poor gastric juice tolerance, LYH5 was encapsulated via extrusion using sodium alginate (SA) and gellan gum. Box-Behnken design optimization yielded optimal parameters: SA 1.5%, gellan gum 0.4%, CaCl2 0.9%, bacteria:glue ratio 1:4, achieving an encapsulation rate of 84.22{+/-}0.17%. Its effect on weaned piglet intestinal health was evaluated using 78 piglets (7.69{+/-}0.52 kg) randomly assigned to 4 groups for 40 days: CON (control), T (basal diet + LYH5 live bacteria, 1x10{superscript 1} CFU/mL), TJ (basal diet + LYH5 microcapsules, 1x10{superscript 1} CFU/mL, J (basal diet + empty capsules). The results of this experiment showed that compared with the control group, LYH5 microcapsule can improve the intestinal barrier function without affecting the growth performance of piglets, and provide ideas and references for the development of human next-generation probiotics (NGP). IMPORTANCEThis study addresses the key bottleneck of poor gastric acid tolerance of probiotics via microencapsulation and provides a practical reference for the development of human next-generation probiotics.

microbiology↗

bioRxiv2026

CEACAM5/6+ Tumor Cells and IL-1β+ Macrophages Drive Resistance to Chemo-immunotherapy in Gastric Cancer

Chemo-immunotherapy is a first-line treatment for advanced gastric cancer, yet response rates remain limited and resistance mechanisms are poorly defined. Here we generate a single-cell atlas of 542,121 cells from 35 patients treated with anti-PD-1 plus chemotherapy, profiling pre- and post-treatment tumors linked to clinical response. Integrating spatial transcriptomics, immunohistochemistry, and bulk RNA sequencing, we identify two temporally distinct resistance programs. Intrinsic resistance in pre-treatment non-responders is marked by enrichment of CEACAM5/6 tumor cells that form immune-excluded spatial niches characterized by macrophage recruitment and CD8 T-cell exhaustion. Acquired resistance in post-treatment non-responders is driven by expansion of IL-1{beta} macrophages, which induces coordinated NF-{kappa}B activation across tumor and stromal compartments, promoting PD-L1 upregulation, epithelial-mesenchymal transition, and chronic inflammation. These findings delineate an evolutionary trajectory of resistance and nominate CEACAM5/6 and IL-1{beta} as predictive biomarkers and therapeutic targets to improve anti-PD-1-based combination strategies.

cancer biology↗

bioRxiv2026

Telomere-to-telomere assembly and haplotype analysis of tetraploid Dendrobium officinale illuminate Orchidaceae polyploid evolution and mycorrhizal symbiosis genes

Dendrobium officinale is a typical epiphytic orchid. We report the telomere-to-telomere (T2T) genome assembly for D. officinale, representing the first T2T reference genome within the Orchidaceae family. The assembly is anchored to 19 chromosomes and contains 38 complete telomeres and 15 characterized centromeres. We further generated haplotype-resolved assemblies of the autotetraploid genome, identifying 12,761 sets of tetra-allelic genes. Based on synonymous substitution analysis, we inferred that the autotetraploidization event occurred approximately 0.86 million years ago. A systematic analysis of the SWEET gene family across the genus Dendrobium revealed that the gene family size is shaped primarily by epiphytic types and environmental factors. In D. officinale from Langshan, eight SWEET genes were specifically expressed in roots, suggesting they may play specialized roles in the root mycorrhizal system, potentially contributing to the D. officinales ability to recruit and maintain fungal partners. Together, these resources provide valuable foundations for studies of orchid evolution, functional genomics, and molecular breeding.

bioinformatics↗

bioRxiv2026

gSV: a general structural variant detector using the third-generation sequencing data

Structural variants (SVs) are major contributors to genome diversity and disease susceptibility, particularly in cancer. Although third-generation sequencing technologies have substantially improved SV detection sensitivity, accurate detection of complex SVs remains challenging due to fragmented and heterogeneous alignment signals, as well as the dependence of many existing methods on predefined variant models. In this paper, we propose gSV, a general SV detector that integrates alignment-based and assembly-based approaches with the maximum exact match (MEM) strategy, with particular emphasis on resolving SVs with complex or atypical alignment signatures. Without predefined assumptions about SV types, gSV captures diverse variant signals, enabling the detection of SVs that are usually missed by conventional tools. Benchmarking using both simulated datasets and real long-read sequencing data demonstrates that gSV achieves improved sensitivity and overall detection performance compared with current state-of-the-art SV callers, particularly for simple and complex SV events with complex alignment patterns. Unique SV discoveries in four breast cancer cell lines, particularly in cancer-associated genes, demonstrate the potential biological relevance of gSV-enabled discoveries. Furthermore, analysis of a breast cancer cohort from the Chinese population highlights the utility of gSV for population-scale genomic studies. Collectively, gSV provides a unified framework for comprehensive SV discovery in both research and clinical genomics settings. O_TEXTBOXKey PointsO_LIExisting structural variant (SV) detection tools are limited in resolving SVs with complex alignment patterns due to their reliance on predefined variant models. C_LIO_LIgSV integrates alignment-based and assembly-based evidence using a maximum exact match (MEM) strategy, enabling capture of diverse and complex SV signals. C_LIO_LIBenchmarking on simulated and real long-read sequencing datasets demonstrates that gSV achieves competitive performance on canonical SV classes and improved sensitivity for complex SV patterns. C_LIO_LIApplication of gSV to breast cancer cell lines and a population-scale breast cancer cohort reveals previously unresolved SVs in cancer-associated genes, highlighting its utility in genomic and clinical studies. C_LI C_TEXTBOX

bioinformatics↗

bioRxiv2026

Evolutionary profile enhancement improves protein function annotation for remote homologs

Accurate annotation of protein function is essential for understanding biological processes, yet this remains challenging for proteins lacking characterized homologs or belonging to underrepresented functional classes. Although machine learning approaches have become the gold standard for automated function prediction, they often perform poorly on out-of-distribution samples with low sequence identity to training proteins with known annotations. We propose EPERep, an evolutionary input enhancement strategy that leverages the vast space of unannotated protein sequences to improve the prediction of the functions of underrepresented proteins. Our key insight is that, even if a query protein has insufficient similarity to annotated proteins for direct annotation transfer, a wider range of similar unannotated sequences can be identified to facilitate better representation learning. Inspired by profile-based sequence search methods, EPERep incorporates homologous sequences as contextual input to refine the representations of individual proteins from pre-trained protein language models, effectively constructing a pLM-based profile for each query protein. Across four major annotation benchmarks on EC numbers, structural domains, Pfam families, and Gene Ontology predictions, EPERep consistently outperforms strong ML and sequence-alignment baselines. Gains are most pronounced for proteins from rare functional classes, with few or no labeled homologs, and for sequences exhibiting remote homology to the training distribution. These results demonstrate that evolutionary input enhancement provides a principled and scalable strategy for improving protein function prediction, particularly in long-tail and low-identity regimes.

bioinformatics↗