Biology subjects

Zhao, H.

Publications and source records attributed to Zhao, H..

At least 109 records · Page 6Linked to original sources

bioRxiv2025

Global Mapping of circRNA-Target RNA Interactions Reveals P-Body-Mediated Translational Repression

Circular RNAs (circRNAs) are primarily produced through pre-mRNA back-splicing, yet their target repertoire and functional mechanisms remain elusive. Here, we present circTargetMap, a computational framework for globally mapping circRNA targets using RNA-RNA interactomes obtained via RNA in situ conformation sequencing (RIC-seq) in the hippocampus and ten human cell lines. This approach identified 117,163 high-confidence circRNA-target RNA interactions, with 83% of target mRNAs bound by multiple circRNAs. Functionally, CDR1as and circRMST repress target mRNA translation by sequestering them into processing bodies (P-bodies)--membraneless granules--through sequence-specific base-pairing, probably independent of AGO2, DICER, and miRNAs. To directly capture granule-associated interactions, we developed granule RIC-seq (GRIC-seq) method, revealing the broad role of circRNA-target RNA interactions in translational repression. Moreover, pathogenic variants are significantly enriched around circRNA-target RNA interaction sites, suggesting potential roles in disease. Our study provides valuable resources for circRNA functional exploration and a framework for investigating RNA-RNA interactions within membraneless organelles.

molecular biology↗

bioRxiv2025

Viral protease-Initiated Pyroptosis Activator mRNA therapy as a Universal Antiviral Strategy

Although therapeutic drugs targeting gasdermin (GSDM)-mediated pyroptosis have made remarkable progress in treating various diseases, their potential for antiviral therapy remains largely unexplored. Inspired by the autoinhibitory mechanism of GSDM proteins and the clinical success of mRNA vaccines, herein we propose a concept of viral protease-initiated pyroptosis (VIP) mRNA therapy as a universal antiviral strategy. Using Hepatitis A virus (HAV) as a model, we rationally engineered an HAV-specific VIP activator (VIPA) by replacing the native gasdermin D (GSDMD) cleavage motif with that of HAV 3C protease. Expression of this VIPA selectively triggered pyroptosis in HAV-infected cells, thereby terminating viral replication. Remarkably, in vivo delivery of VIPA mRNA via lipid nanoparticles (LNPs) significantly suppressed viral replication and shedding, alleviated liver injury, and elicited a pyroptosis-driven antiviral immune response in uninfected cells. Similarly, VIPA against Zika virus (ZIKV) also exhibited potent antiviral efficacy in both cell culture and mouse models. Furthermore, a generative artificial intelligence (AI) platform was deployed to design de novo cleavage motifs for the SARS-CoV-2 main protease NSP5, together with experimental screening, yielding optimized VIPAs with enhanced antiviral potency. Our work establishes the concept of VIPA mRNA therapy as a versatile platform for the treatment of diverse viral infections via "kill-and-alert" mechanism.

microbiology↗

bioRxiv2025

Gut Microbiota-derived Adenosine Determines the Efficacy of Electroconvulsive Therapy for Depression

Electroconvulsive therapy (ECT) is a final procedure for major depressive disorders (MDD). However, the effectiveness of ECT in treating MDD patients varies. Here we identified gut microbiota as a potential restraining factor of ECT efficacy. By using a 5-day electroconvulsive shock (ECS) in depression mouse model of chronic restraint stress (CRS), it was observed that the antidepressant effect of ECS was suppressed after antibiotics (ABX)-induced microbiota dysbiosis, which also resulted in elevated c-Fos expression of CRH neurons in paraventricular nucleus of hypothalamus (PVN) and increased serum corticosterone levels after ECS. Metabolomic analysis revealed the critical involvement of microbiota associated purine metabolism, and the supplement of gut microbiota-derived adenosine was able to recover the antidepressant effect of ECS in ABX-treated CRS mouse model. Based on the neural tracing from colon to brain and the immunofluorescence staining, it was surmised a gut-brain axis originated from Adora1-expressing cells in colon mediate this biological process. Furthermore, adenosine supplement alleviated the further deterioration of post-ECS memory loss and impairment of synaptic plasticity induced by ABX-treatment as well. Our findings suggest a potential role of microbial adenosine metabolism in ECT efficacy determination and side effect protection, highlights potential application of adenosine supplement in antidepressant therapies of those depression patients with microbiota dysbiosis.

systems biology↗

bioRxiv2025

Streptavidins play a multifunctional role within a biotin-pathway antibiotic network encoded in a biosynthetic supercluster

Streptavidin, the well-known biotin-binding protein extensively used in biotechnology, is naturally co-produced in Streptomyces avidinii alongside stravidins--inhibitors of biotin biosynthesis. Here, we uncover and activate a conserved genomic region flanked by two streptavidin genes, revealing multiple biosynthetic gene clusters that produce diverse biotin-related metabolites, including stravidins, acidomycin, -methyl-KAPA, -methyldesthiobiotin, and the novel non-proteinogenic amino acid ANDA. We show -methyldesthiobiotin arises from -methyl-KAPA, illustrating how methylated analogues interfere with distinct steps of biotin biosynthesis. Contrary to the view that streptavidin functions solely by sequestering biotin, our biochemical, structural, and bioactivity analyses demonstrate that it also binds acidomycin, neutralizing its antibacterial activity to protect the producer while likely facilitating compound secretion. The crystal structure of the streptavidin-acidomycin complex reveals the molecular basis for this dual functionality. Our findings establish a multifunctional streptavidin that integrates biotin sequestration and self-resistance to balance an antibiotic network targeting the biotin pathway in microbial competition.

microbiology↗

bioRxiv2025

Host EV derived lipids promote malaria parasite development via mosquito fatty acid oxidation

Malaria parasites must transition between mammals and mosquitoes, but how they adapt to such distinct environments is unclear. We show that blood from infected mammals buffers this environmental shift by packaging parasite-induced signals into extracellular vesicles (EVs). EVs internalized by mosquito midgut increases expression of VLCAD and raises levels of a 22-carbon fatty acid, driving fatty acid breakdown and acetyl-CoA production. The parasite exploits this metabolic shift to synthesize its own lipids during oocyst growth. Stable isotope tracing confirmed that13C4-labelled behenic acid is degraded and incorporated into parasite fatty acids. Lipidomic profiling further revealed that ceramides enriched in the EVs are key mediators. These findings identify a mechanism by which host bood-derived EVs reprogram mosquito lipid metabolism to promote parasite transmission.

microbiology↗

bioRxiv2025

A novel allele of Sh1 underlines the conversion of waxy corn to wx-sweet corn

AbstractWaxy corn and sweet corn are two major types of fresh-eating corn. Each has significant market value due to its unique sensory and nutritional profiles. Developing a variety that combines both traits would meet growing consumer demand and create new market opportunities. From a fast neutron-mutagenized population of the waxy corn inbred line HB522, we identified a mutant, wx-sweet, whose kernels exhibit both waxy and sweet properties at the filling stage. Using bulked segregant analysis (BSA) and fine mapping, we localized the causal locus to SHRUNKEN1 (Sh1) on chromosome 9, which was confirmed by an allelic test with a known Mu-insertion mutant. PCR and sequencing indicated a putative large structural variation in the second and third exons of Sh1 in wx-sweet, likely disrupting the reading frame. This novel sh1 allele significantly reduced sucrose synthase activity. The sh1 and waxy1 mutant genes act synergistically to remodel carbohydrate metabolism in wx-sweet endosperms. This remodeling, revealed by integrated transcriptomic and metabolomic analyses, drives transcriptional reprogramming and restructures metabolic flux. These changes thereby enhance sucrose and raffinose accumulation, which underlies the unique waxy-sweet texture in fresh-eating maize endosperm. In summary, our work not provides valuable genetic resources for fresh-eating corn breeding, but also elucidates, for the first time, the molecular mechanism underlying the synergistic formation of waxy and sweet texture. Key messageThe novel allele of Sh1 acts synergistically with waxy1 to regulate carbohydrate metabolism, which elucidates the molecular mechanism for the unique waxy-sweet texture in fresh-eating corn endosperm. Our work provides new strategies for sweet-waxy maize breeding.

genetics↗

bioRxiv2025

Deep learning assessment of nativeness and pairing likelihood for antibody and nanobody design with AbNatiV2

1Immune systems create antibodies that balance good binding and stability with low toxicity and self- reactivity. Quantifying the nativeness of a candidate sequence - its likelihood of belonging to natural immune repertoires - has thus emerged as a valuable strategy for hit selection from synthetic libraries, optimisation and humanisation, and for guiding de novo design towards developable candidates. We previously introduced AbNatiV, a transformer-based VQ-VAE for nativeness assessment, which proved effective across multiple nanobody engineering tasks. However, AbNatiV1 operated on unpaired sequences, limiting applicability to conventional VH-VL antibodies. Moreover, its performance on nanobody nativeness was constrained by the limited number and diversity of nanobody repertoires available at the time. Here, we sequenced new camelid repertoires, curated additional recent datasets, and present AbNatiV2: an enhanced architecture comprising various models each trained on [≥] 20 million sequences. AbNatiV2 improves nanobody nativeness classification across held-out and diverse test sets, and more robustly detects nativeness changes upon CDR grafting. We also introduce p-AbNatiV2, a cross-attention model fine-tuned on 3.7 million paired human sequences. p-AbNatiV2 provides residue- and sequence-level humanness for VH/VL pairs and learns pairing-likelihood via noise-contrastive training. On held-out tests, it assigns the native pair a higher score in 74% of cases, substantially outperforming recent pairing models. Together, AbNatiV2 and p-AbNatiV2 extend nativeness assessment and engineering to both nanobodies and conventional antibodies, supporting design decisions at single-residue, Fv-sequence, and paired-domain levels. We make AbNatiV2 available as downloadable software and webserver.

bioengineering↗

bioRxiv2025

VRC01 Selects Rare HIV Escape Mutations After Acquisition in Antibody-Mediated Prevention Trials

Broadly neutralizing antibodies (bnAbs) show promise in HIV prevention, yet viral escape remains a challenge. In the Antibody Mediated Prevention (AMP) trials, the CD4 binding site (CD4bs) bNAb VRC01 blocked acquisition by VRC01-sensitive strains. However, its influence on viral evolution post-acquisition is not fully understood. Here we analyzed >12,000 HIV env sequences from 47 participants from the AMP trials, identifying VRC01-mediated de novo escape mutations in 8 of 26 VRC01-treated participants but none in 21 placebo participants. These mutations were found at very low frequency (<1%) in global viruses. Escape mutations, primarily located in the Loop-D and {beta}23/V5 regions of Env, conferred cross-resistance to several CD4bs bnAbs, while more potent CD4bs bnAbs like N6 and 1-18 largely retained their activity. Our findings demonstrate that prophylactic VRC01 can select for viral escape after infection, underscoring the need for next-generation bnAbs with improved breadth and potency to enhance durability and efficacy of antibody-based HIV prevention.

microbiology↗

bioRxiv2025

Structure and function of the nairovirus cap-snatching endonuclease

Nairoviruses include several human pathogens such as Crimean-Congo hemorrhagic fever virus (CCHFV) and Kasokero virus (KASV). The cap-snatching endonuclease (EN) domain of the viral polymerase is essential for transcription and represents a promising antiviral target. However, the structural and functional mechanisms of nairovirus ENs remain poorly understood. Here, we describe biochemical and structural studies of the ENs from CCHFV and KASV. Biochemical assays demonstrate that the RNA endonuclease activity of both ENs is activated by manganese ions and exhibits a preference for uridine-rich RNA substrates. This activity is inhibited by three metal-chelating inhibitors (DPBA, L-742,001, and BXA), with BXA displaying the highest binding affinity and inhibitory potency. We further determine nine crystal structures of CCHFV and KASV ENs in apo, metal ion-bound, and inhibitor-bound states. Comparative structural analysis uncovers a two-metal-ion binding mode unique to nairovirus ENs, in which conserved residues coordinate two manganese ions via bridging water molecules. In the inhibitor-bound structures of KASV EN, BXA forms additional stabilizing interactions with the enzyme, explaining its superior inhibitory effect. Functional assays further confirm that the two-metal-ion mechanism is critical for viral transcription. These findings provide a structural foundation for the rational design of antivirals against CCHFV and related pathogens.

microbiology↗

bioRxiv2025

Electrostatic Interaction Determines the Docking Specificity and the Formation of Functional Cx36 Gap Junction Channels

Connexin36 (Cx36) is broadly expressed in neurons and serves as the principal protein that forms interneuronal gap junctions (GJs), also known as electrical synapses. Recent high-resolution structures of human Cx36 GJ have revealed crucial electrostatic interactions (ESIs) of charged residues between two docked Cx36 hemichannels at the second extracellular (E2) loops. Despite their structural importance, the mechanistic roles of these ESIs remain poorly understood. To investigate their significance, we systematically designed and tested a series of missense variants targeting key E2 interface residues, aiming to disrupt or modulate the electrostatic landscape at the docking interface. Based on the ESI pairs defined from the crystal structure, our combined computational calculations and dual patch-clamp experiments in engineered HEK293 cell pairs suggest that at least three ESI residual pairs per E2-E2 interface are required to support functional GJ formation. Furthermore, we found that these unique ESIs of Cx36 could play a role in its docking specificity to itself, as they rarely form heterotypic GJs with other brain connexins. Overall, these findings provide essential molecular and functional insights into the mechanisms governing Cx36 GJ formation and partner specificity, paving the way for future therapeutic approaches targeting connexin dysfunction in human diseases.

neuroscience↗

bioRxiv2025

Distinct and compensatory roles of Stag1 and Stag2 in post-mitotic genome refolding

The three-dimensional architecture of the eukaryotic genome is largely shaped by the cohesin complex, which contains either Stag1 or Stag2 subunits. Although both subunits contribute to chromatin organization, their specific functions in de novo loop formation during post-mitotic genome refolding remain elusive. Here, we leverage the mitosis-to-G1 transition to dissect their individual roles. We found that Stag1 depletion has a negligible impact on post-mitotic genome restructuring or transcription reactivation. In contrast, Stag2 orchestrates chromatin remodeling in a manner that is both cell cycle stage-specific and chromatin context-dependent. During early-G1, Stag2 preferentially associates with euchromatin, where it drives the rapid formation of small chromatin loops. This facilitates prompt promoter-enhancer (P-E) contact formation and enables efficient transcription activation. As the nuclear concentration of Stag2 increases by late-G1, it progressively suppresses large loops, likely due to its shorter chromatin residence time and its potential to competitively displace the more extrusion-capable Stag1-associated cohesin. Mechanistically, Stag2-mediated loop extrusion is constrained by CTCF-bound barriers, rather than by genomic travel distance. Although Stag2 associates rapidly with euchromatin in early-G1, its recruitment to heterochromatin is delayed until late-G1. Simultaneous depletion of both Stag proteins results in a synergistic loss of virtually all structural loops and a more severe disruption of transcription than that caused by individual deletions. Together, these results establish Stag2 as the principal regulator of post-mitotic genome reorganization among Stag paralogs, mediating spatiotemporal control of chromatin architecture, while Stag1 provides compensatory support to ensure functional robustness.

molecular biology↗

bioRxiv2025

HuBIE: The Human Blood Immunome Encyclopedia Of TCRs and BCRs in Bloodstream Infections and Cancer

T and B cells are central to adaptive immunity, where they identify and neutralize foreign antigens and cancer neo-antigens. Large-scale elucidation of T- and B-cell receptors (TCRs and BCRs) through immune-repertoire sequencing promises novel diagnostics, prognostic markers, and therapeutic strategies. However, progress is hampered by small cohort sizes, a lack of real-world patient diversity, and heterogeneous sample processing, impeding cross-study comparability. To overcome these limitations, here we introduce the Human Blood Immunome Encyclopedia (HuBIE), comprising immune-repertoire data from 2,614 samples collected from 1,941 participants. The cohort includes a range of bloodstream infections, several cancer types, and control participants, with many individuals providing longitudinal samples. We employed Roches immune receptor Primer Extension Target Enrichment (immunoPETE) platform to perform simultaneous targeted sequencing of T-cell receptor {beta} chains (TRB), T-cell receptor {delta} chains (TRD), and immunoglobulin heavy chains (IGH), thereby profiling TCRs and BCRs in all participants. We provide a comprehensive description of immune-repertoire diversity in cancer and bloodstream infections and examine variations across demographic variables such as age and race. We find significant differences in TRB and IGH composition across ethnic groups, and show that the fall in repertoire diversity with age follows distinct patterns for TRB, TRD, and IGH and is accompanied by age-related differences in VJ gene usage. Finally we demonstrate that greater immunological diversity is associated with improved survival but only for elderly participants. HuBIE thus constitutes a valuable resource for the immune-repertoire community, enabling large-scale mapping of the human immunome to accelerate development of diagnostics, prognostic biomarkers, and innovative therapeutic strategies.

immunology↗

bioRxiv2025

Beyond the Genotype: A Multi-Omic Analysis of APOEe4's Role in Alzheimer's Disease

Alzheimers disease (AD) is characterized by widespread molecular dysregulation, with the APOEe4 allele recognized as its strongest genetic risk factor. However, the mechanisms by which APOEe4 drives distinct molecular changes - whether by exacerbating pathology or triggering compensatory responses - remain incompletely understood. We generated and analyzed proteomic, epigenetic, and genetic data from post-mortem dorsolateral prefrontal cortex samples of a uniquely APOEe4-enriched subset of the Religious Orders Study and Memory and Aging Project (ROSMAP). Specifically, we generated DIA LC-MS proteomic data (n = 302), analyzed previously generated DNA methylation profiles from our group (n = 310), and used published whole-genome sequencing data (n = 254) to compute polygenic risk scores (PRS). In this cohort, 69% (n = 214) were APOEe4 carriers, and 19.6% (n = 42) of them showed no pathological evidence of AD based on NIA-Reagan criteria, enabling identification of APOEe4-related risk and resilience mechanisms. In the absence of AD, APOEe4 carriers exhibited lower levels of 27 proteins, suggesting early synaptic (e.g., VAMP1, SYN3, CASKIN1) and metabolic (e.g., GLUD1, PI4KA) vulnerability. By contrast, APOEe4 carriers with AD displayed marked upregulation of inflammatory and proteostatic proteins (e.g., GNAO1, AHNAK, FGG, HEBP1, APEX1, RAB4A, SLC12A5, LRP1, BAG6) and hypermethylation of cg06329447 in ELAVL4. Network analyses highlighted convergent disruptions in synaptic transmission, metabolism, and proteostasis - key pathways altered in APOEe4-associated AD. Mediation analyses identified GRIPAP1 and GSTK1 as top protein mediators (accounting for [~]26-33% of APOEe4s effect), with VAMP1, CASKIN1, DPP3, SYN3, and FGG each contributing [~]9-15%. ELAVL4 hypermethylation also mediated [~]12% of the APOEe4 effect, linking epigenetic dysregulation to disease risk. To assess whether the identified proteins reflected broader genetic risk for AD or were specific to APOEe4, we calculated PRS both excluding and including the APOE genomic region. While the non-APOE PRS showed no association with identified molecular markers, the APOE-inclusive PRS was significantly associated with eight AD-related proteins in carriers, indicating they are not explained by polygenic risk outside of APOE. Finally, predictive modeling stratified by APOEe4 status revealed that in non-carriers, PRS most effectively classified AD (AUC = 0.73), whereas in carriers, proteomic and epigenetic markers outperformed PRS (AUC up to 0.74). Together, these findings demonstrate that APOEe4 confers AD risk through early synaptic and metabolic disruptions and later-stage inflammatory and epigenetic changes, laying the groundwork for genotype-tailored biomarker development and therapeutic strategies. VISUAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=156 HEIGHT=200 SRC="FIGDIR/small/682426v1_ufig1.gif" ALT="Figure 1"> View larger version (31K): org.highwire.dtl.DTLVardef@1477a2forg.highwire.dtl.DTLVardef@1a6d173org.highwire.dtl.DTLVardef@1010821org.highwire.dtl.DTLVardef@bcde3a_HPS_FORMAT_FIGEXP M_FIG C_FIG

pathology↗

bioRxiv2025

An angiopoietin-2 vaccine improves arteriovenous malformation pathology in hereditary hemorrhagic telangiectasia mice

Hereditary hemorrhagic telangiectasia (HHT) is a genetic vascular disorder that causes systemic arteriovenous malformations (AVMs) associated with severe complications. Angiopoietin (ANG)-2 has been identified as a consistently upregulated secreted protein across various HHT models, and neutralizing ANG2 reduces AVMs in mice. ANG2 has thus emerged as a potential target for HHT treatment. Here, we report the development of a peptide vaccine (ANG2-P3:CRM197) that selectively targets ANG2 over ANG1 and tested its effectiveness in decreasing retinal AVMs in neonatal mice injected with BMP9/10 blocking antibodies, a model of HHT. Litter groups from female C57BL/6 mice immunized with ANG2-P3:CRM197 received injections of anti-BMP9/10 antibodies, and their retinas were examined for vascular pathology. The potential toxicity of the vaccine was evaluated in females 12 months post-immunization through echocardiography, basic metabolic panels, and lipid profiles. Circulating anti-ANG2 antibodies were detected in nursing neonates of vaccinated females, with antibody levels comparable between litters and their dams, indicating effective antibody transfer from the dams. A significant decrease in AVM number and size was observed in the retinas of pups exposed to ANG2-P3:CRM197 antibodies compared to unexposed pups. Arterial and venous diameters were normalized in the vaccinated pups retinas. The vaccinated females showed no abnormalities in cardiac, liver, or kidney functions. A vaccine strategy targeting ANG2 appears safe and improves AVM pathology in HHT mice. These findings further support the potential of inhibiting ANG2 as a viable approach for treating AVMs in HHT. KEY POINTSO_LIA peptide vaccine that targets ANG2 reduced AVM number and size, and normalized arterial and venous diameters in a mouse model of HHT. C_LIO_LIThe vaccine did not cause any abnormalities in cardiac, liver, or kidney functions, and thus appeared safe. C_LI

cell biology↗

bioRxiv2025

Long-Read Deep Sequencing Reveals High Rates of Multilineage Transmission and Rapid Viral Population Changes in Acute HIV Infection

Understanding the selective forces acting upon HIV early in infection is crucial to design prevention strategies. By leveraging deep sequencing and the short diagnostic intervals of the FRESH and RV217 cohorts (median 4 days) between the last-negative and first-positive RNA tests, we captured a precise and early snapshot of acute HIV infection. The frequency of multiple transmitted viruses of 38% in these as well as placebo recipients from the AMP trials was higher than previously published, with the true frequency likely to be higher. The relative abundance of lineages fluctuated substantially over time in two-thirds of the multilineage infections, generating uncertainty in identifying the specific viruses that were transmitted and founding the infection. Viral populations exhibited diversity and selection on the Gag and Env proteins at the earliest times examined, with sites inferred to be undergoing negative selection most evident. These data may help explain vaccination failures and provide new targets for prevention.

microbiology↗

bioRxiv2025

Maternal Influenza A Virus Infection Induces Antiviral and Immune Dysregulation in the Placenta and Fetus Without Vertical Transmission

Influenza A virus (IAV) infection during pregnancy is associated with stillbirth and preterm birth, but the degree to which IAV alters placental and fetal immunity is poorly understood. The objective of our study was to determine the immunologic impact of maternal IAV infection on the placenta and fetus in a pigtail macaque (Macaca nemestrina) model. Pregnant pigtail macaques were inoculated with 107 plaque forming units (PFU) of IAV [A/California/07/2009 (H1N1)] and underwent necropsy 5 days post-infection (N=11). Results were compared to uninfected historical controls (N=16). IAV inoculation induced maternal pneumonia in all cases. Stillbirth occurred in 18% (2/11) of IAV-infected pregnancies, but not in controls. While vertical transmission was not observed, low-level IAV viral RNA was detected in two placentas. In the placenta, maternal IAV infection was associated with increased IL-1{beta}, IL-18, and IFN-{beta} levels, and an upregulated type I interferon (IFN) transcriptional response. IAV infection was also associated with significantly higher frequencies of intermediate and non-classical monocytes, plasmacytoid dendritic cells, CD4 T cells, and NKT cells in the fetus (lung, lymph node, blood). Although placental immune and transcriptional perturbations were rarely correlated with maternal IAV disease indicators (e.g., maternal lung viral load/IFN-/IFN-{beta}/IL-6), there were consistent and significant correlations between these metrics and perturbed immune cell populations in the fetus (CD4+ and CD8+ T cells, plasmacytoid dendritic cells, monocyte sub-populations). Maternal IAV infection disrupted both placental and fetal immune environments, but only fetal immune alterations correlated with maternal lung disease severity. One Sentence SummaryMaternal influenza A virus infection in pregnant pigtail macaques dysregulates placental and fetal immunity, with disease severity correlating strongly with fetal, but not placental, immune perturbations.

systems biology↗

bioRxiv2025

Acidic transcription factors position the genome at nuclear speckles through transcription dependent and independent mechanisms

A small fraction of the genome positions reproducibly near nuclear speckles (NS), increasing expression and/or splicing efficiency of NS-associated genes. How specific genomic regions target to NS remains unclear. Here, we demonstrate that establishment of genome-wide NS-association occurs independent of active transcription. We show that DNA sequences derived from NS-associated regions integrated as transgenes autonomously target to NS. By systematically dissecting one such genomic locus, the COL1A1-SGCA locus, we identified redundant NS-targeting cis regulatory elements, including a [~]600 bp fragment with 17 binding motifs for 8 transcription factors (TFs). Four NS-targeting TFs within this fragment contain acidic activation domains (AADs) that provide both chromatin-context and transcription-dependent NS-targeting, a property that appears common among several other tested AADs. A subset of acidic activator TFs contain an additional, transcription-independent NS-targeting activity. Our findings establish diverse and partially redundant NS-targeting activities, which may facilitate dynamic gene positioning at NS periphery for context-specific transcriptional responses.

cell biology↗

bioRxiv2025

scGPD: single-cell informed gene panel design for targeted spatial transcriptomics

In targeted spatial transcriptomics technologies, a key challenge is to select an informative gene panel that captures the complexity of cellular and spatial heterogeneity within tissues. Many existing methods use prior knowledge or heuristic selection rules, such as selecting highly variable genes, which overlook gene-gene correlations and may consequently result in suboptimal coverage. To address the limitations of the existing methods, we introduce scGPD, a deep learning-based framework for gene panel design that leverages single-cell RNA-seq data to identify compact, nonredundant sets of genes for spatial profiling. scGPD uses a gene-gene correlation-aware gating mechanism to extract informative features from data, encouraging diversity among selected genes and eliminating redundancy. Across diverse single-cell datasets, scGPD outperforms existing gene panel design methods in recovering transcriptome-wide expression using a limited number of genes. When applied to spatial transcriptomics data, it achieves superior cell type classification accuracy, demonstrating strong generalization across modalities. The gene panels selected by scGPD further exhibit well-defined spatial expression patterns, highlighting their robustness and relevance for spatial analysis. The scGPD framework is flexible and can be adapted to multiple use cases, enabling the prioritization of genes relevant to specific diseases or phenotypes. Together, these results demonstrate that scGPD provides a robust and adaptable solution to design efficient gene panels for spatial transcriptomics, with broad applicability to tissue mapping and disease characterization.

bioinformatics↗