Biology subjects

Tian, W.

Publications and source records attributed to Tian, W..

At least 19 recordsLinked to original sources

bioRxiv2026

Domain-resolved epitope mapping of B7-H3-targeting VHH-Fcs defines isoform-selective binders for antibody-drug conjugate development

The immune checkpoint molecule B7-H3 has emerged as one of the most actively pursued therapeutic targets in solid tumors, and multiple B7-H3-targeting antibody-drug conjugates have entered clinical evaluation. B7-H3 occurs as a 2Ig isoform carrying a single IgV-IgC domain pair and a predominant 4Ig isoform carrying two tandem pairs of near-identical sequence in their extracellular domains. Resolving which pair an antibody engages, or how antibodies distinguish the two isoforms, requires epitope mapping at residue level. Here we generated a panel of six B7-H3-targeting VHH-Fcs and characterized them by surface plasmon resonance, epitope binning, domain-resolved deep mutational scanning and receptor internalization, benchmarked against the clinically advanced antibodies ifinatamab, mirzotamab and vobramitamab. Most VHH-Fcs bound the membrane-proximal pair more tightly than the distal pair, and 4Ig 10- to 100-fold more tightly than 2Ig, whereas the three clinical antibodies showed no such discrimination. Displaying each domain pair independently on yeast identified the residues that account for this selectivity. Internalization varied several-fold among binders, including between VHH-Fc 620 and 636, which have near-identical footprints and comparable affinities. VHH-Fc 620 internalized most efficiently, also compared to ifinatamab, and was conjugated to exatecan through a protease-cleavable linker. The conjugate showed B7-H3-dependent cytotoxicity that scaled with B7-H3 cell surface density, though it was less potent than ifinatamab-exatecan. Affinity, epitope and internalization therefore behaved as independent characteristics rather than integrating to predict antibody-drug conjugate potency. Together, these results define the molecular basis for isoform-selective recognition of B7-H3 and identify VHH-Fc 620 as a starting point for isoform-selective targeting.

cancer biology↗

bioRxiv2026

Lactate epigenetically shapes tumor cell states in H3K27M diffuse midline gliomas

H3K27M diffuse midline gliomas (DMGs) are lethal and lack treatment options. These tumors exhibit tumor heterogeneity with aggressive oligodendrocyte precursor (OPC)- and mesenchymal (MES)-like cell states. Because all tumor cells bear H3K27M, tumor heterogeneity has been attributed to microenvironmental cues that remain obscure. H3K27M DMGs exhibit increased glycolysis and the Warburg effect to produce lactate. Lactate can directly modify histone lysines including H3K27Lac, and we hypothesized that lactate epigenetically regulates tumor cell states in H3K27M DMGs. We undertook a comprehensive and integrated analysis of H3K27M DMG cell lines, animal models, tumor tissues, and magnetic resonance spectroscopy in patients to decipher the epigenetic roles of lactate. Here, we report that H3K27M cells uniquely exhibit elevation of the activating mark H3K27Lac. We observed significant heterogeneity in lactate levels within tumors, and the addition of exogenous lactate resulted in marked increases in H3K27Lac and the expression of critical OPC- and MES- like gene signature genes, which correlates with poorer patient outcomes. Our therapeutic approach leverages the inhibition of CBP/p300, which deposits both H3K27Lac and H3K27ac. Targeting CBP/p300 effectively reduces both H3K27Lac and H3K27ac levels, suppresses key OPC- and MES-like signatures, and shows efficacy in preclinical models. Collectively, our findings identify lactate as a key player in the epigenetic regulation of tumor cell state heterogeneity and suggest that targeting this pathway offers promise for addressing the heterogeneous complexities of H3K27M DMGs.

molecular biology↗

bioRxiv2026

Lysyl oxidase drives ccRCC progression by coordinating HIF-2α transcription program with tumor microenvironment

Clear cell renal cell carcinoma (ccRCC) is driven by persistent HIF-2 transcription program initiated by VHL loss, yet molecular mediators sustaining this program are poorly defined. Using single-cell transcriptomics, we identified lysyl oxidase (LOX) as a driver of ccRCC progression, selectively enriched in a hypoxia/epithelial-mesenchymal transition (EMT) gene program associated with poor outcome. While LOX oxidizes and stabilizes HIF-2 by antagonizing HUWE1-mediated ubiquitination and degradation, thereby sustaining HIF-2-driven transcription in cancer cells, it also remodels extracellular matrix (ECM) and promotes angiogenesis in the tumor microenvironment (TME). Genetic or pharmacological inhibition of LOX destabilizes HIF-2, disrupts ECM, inhibits angiogenesis, and suppresses tumor initiation, growth, and metastasis in vivo. LOX inhibition enhances anti-angiogenic therapy response and remains effective in belzutifan-resistant HIF-2 G323E-mutant tumors. Nuclear LOX protein correlates with nuclear HIF-2 in high-grade patient tumors. Together, LOX coordinates HIF-2 transcription program with TME and is a therapeutic target in ccRCC.

cancer biology↗

bioRxiv2026

Structure of the human HIRA histone chaperone with a nucleosome suggests a stepwise nucleosome assembly mechanism

The restoration of chromatin in the wake of a DNA or RNA polymerase is essential to maintain the integrity of eukaryotic genomes. Human HIRA is a 1.8-megadalton, three-subunit histone chaperone that mediates all replication-independent deposition of the histone variant H3.3 at active chromatin regions1-6. Disruption of HIRA perturbs active-chromatin organization and has wide-ranging consequences for development, cellular senescence, and genome integrity7-11. Despite its central biological role in reassembling nucleosomes post-transcription, the structure of native human HIRA and the mechanism by which it organizes histones and DNA during nucleosome assembly remain unknown. In particular, the function of the largest HIRA subunit CABIN1 is enigmatic. Here, we show that HIRA is not simply a passive histone hand-off factor but remains engaged across multiple stages of nucleosome assembly, including a close interaction with the nucleosome. Cryo-EM structures reveal that HIRA forms an extended arch-like structure that binds the nucleosome primarily through extensive CABIN1 contacts with histones, histone tails, nucleosomal DNA, and linker DNA, during the final stage of nucleosome assembly. Together, our results suggest a testable mechanism for HIRA-mediated nucleosome assembly and product release and provide the basis for elucidating the molecular details of this fundamental biological process.

biochemistry↗

bioRxiv2026

TFAM organizes DNA into compact higher order structures

TFAM (Transcription Factor A, Mitochondrial) is an essential human protein that plays two key roles in mitochondrial DNA (mtDNA) homeostasis. TFAM acts as a transcription factor that specifically binds to promoter regions, but it is also solely responsible for organizing mtDNA into nucleoids by nonspecifically covering the entire genome. Many studies have addressed TFAM in transcription regulation, but its role as a genome organizing entity is not well characterized. The current understanding of how TFAM compacts DNA into nucleoids is based on crystal structures of a TFAM monomer bound to short fragments of DNA (22-28 bp). However, this does not adequately reflect the biological role of TFAM in organizing the nucleoid where multiple TFAM molecules oligomerize on the 16.5 kb genome to form the nucleoid. Here, we present a biochemical and structural analysis of TFAM oligomerization on longer DNA. Our results show that TFAM compacts longer segments of DNA into higher order complexes that are homogenous yet exhibit continuous conformational dynamics. Significance statementMutations or damage to mitochondrial DNA (mtDNA) severely impairs cellular respiration and is implicated in many human diseases and aging. Transcription Factor A, Mitochondrial (TFAM) is an essential protein that is solely responsible for packaging mtDNA into nucleoids thereby shielding it from DNA damage. Despite its importance, the mechanism by which this is accomplished is poorly understood. Here, we use biochemistry to show that TFAM oligomerizes on DNA to form compact, homogenous higher order structures in solution. We also examined these complexes at a low resolution using cryo-EM, suggesting an organizational unit of mtDNA. This work reveals there may be a regular organization to mitochondrial nucleoids, providing the basis for further understanding mtDNA compaction by TFAM.

biophysics↗

bioRxiv2026

Wnt/β-catenin signaling restrains developmental beiging and imprints long-term energy expenditure

Beige adipocytes that emerge during the peri-weaning period support sympathetic nervous system (SNS)-independent thermogenesis, yet the mechanisms governing this spontaneous beiging remain unclear. Here, by integrating transcriptomic profiling with adipocyte-targeted Ctnnb1 deletion in mice, we identify the canonical Wnt signaling as an endogenous brake on developmental beige thermogenesis. Peri-weaning inguinal fat from adipocyte Ctnnb1 knockout mice exhibits enhanced beige adipocyte biogenesis, with increased thermogenesis-related gene expression and mitochondrial oxidative capacity, which programs durable activation of adaptive thermogenesis and augmented whole-body energy expenditure into adulthood. Mechanistically, suppression of Wnt/{beta}-catenin signaling induces a non-canonical Wnt5a-Ca2-AMPK axis that promotes triglyceride lipolysis and subsequent PPAR-driven fatty acid oxidation, thereby fueling mitochondrial respiration. Genetic or pharmacological disruption of this axis blunts thermogenic responses induced by {beta}-catenin inhibition in both murine and human subcutaneous adipocytes, indicating that Wnt5a-Ca2-AMPK axis is required for the cell-autonomous activation of beige fat. These results reveal Wnt/{beta}-catenin signaling as a developmental constraint on beige adipocyte formation and suggest an SNS-independent route to sustainably raise energy expenditure and improve metabolic health.

physiology↗

bioRxiv2026

Glycoengineering of extracellular vesicles enhances cellular uptake and cargo delivery to target cells

The glycocalyx is a major regulator of membrane recognition, yet its specific influence on extracellular vesicles (EVs) cellular uptake remains poorly defined. We established a genetic glycoengineering platform to systematically investigate how the major glycan classes on small EVs (sEVs) modulate cell interactions and functional cargo delivery. Using an isogenic panel of HEK293F lines lacking distinct glycan biosynthetic pathways, we find that removing glycosaminoglycans ({Delta}GAG-sEVs) yields a strong increase in cellular uptake and delivery of diverse cargos, including DNA oligonucleotides, siRNA, proteins, and plasmid DNA. Glycan-modified recipient cells show that sEV-cell communication and internalization is jointly governed by glycan features on both membranes. {Delta}GAG-sEVs strongly improve gene delivery and expression in recipient cells and in a physiologically relevant human airway epithelial model. These findings establish glycan structures as tunable regulators of sEV uptake and position {Delta}GAG-sEVs as potent vehicles for improved drug delivery and gene therapy.

bioengineering↗

bioRxiv2026

A Multimodal Single-Cell Epigenomic and 3D Genome Atlas of the Human Basal Ganglia

The basal ganglia (BG) underlie motor control, reward processing, and many neurological and psychiatric disorders, but a comprehensive epigenomic and 3D-genome atlas of the human BG is lacking. Here we present a multimodal single-cell atlas profiling DNA methylation and 3D chromatin conformation in 261,331 nuclei (snm3C-seq) across eight subregions, resolving 12 classes, 31 subclasses, and 59 groups. Harmonized under the HMBA basal-ganglia consensus taxonomy, this atlas integrates with matched RNA, ATAC-seq, and histone-modification data across five regulatory layers. We identify millions of cell-type- and region-specific differentially methylated regions enriched for distinct transcription factor motifs and link them to disease-associated heritability. Neuron-specific loops dominate cell-type-specific 3D contact remodeling, while most non-neuron-specific loops are constitutive. Among spiny projection neurons (SPNs), chromatin loops, rather than TAD boundaries, distinguish D1, D2, and eccentric SPN subclasses, with eccentric SPNs showing the most loop-level reorganization among the three. We characterize STR D2 SMYD2-HTR7 SPN, a newly recognized POU6F2 D2-SPN subtype, and reveal region-specific methylation and contact gradients of disease-associated genes, including CADM1 and PDE8B. Integrative gene-regulatory networks reconstruct cell-type-resolved enhancer-promoter links to interpret Parkinsons disease risk variants at SNCA. Finally, MERFISH spatial profiling combined with cross-species Patch-seq identifies non-SPN neuronal subtypes, including a MOXD1 striosomal STR FS PTHLH-PVALB GABA subtype with distinct electrophysiology, partitioning across the striatal matrix-striosome boundary. HighlightsO_LIA multimodal single-cell atlas maps DNA methylation and 3D genome architecture across human basal ganglia cell types and subregions. C_LIO_LINeuron-specific loops dominate cell-type-specific 3D contact remodeling in the human BG, whereas most non-neuron-specific loops are constitutive. C_LIO_LISpiny Projection Neuron (SPN) subtypes exhibit regionally organized epigenomic and 3D genome signatures that align with dorsal-ventral identities. C_LIO_LIChromatin loops are the primary distinguishing feature among D1, D2, and eccentric SPN subclasses, with eccentric SPNs being the most 3D-reorganized. C_LIO_LIIntegrated regulatory maps link cell-type-specific enhancers to disease-associated genetic risk in the human basal ganglia. C_LIO_LINon-SPN interneurons differ in distribution and in transcriptional and epigenetic identity across the matrix-striosome boundary. C_LI

neuroscience↗

bioRxiv2025

Phosphorylation remodels the mitotic centrosome matrix to generate bipartite gamma-tubulin complex docking sites

Mitotic centrosomes consist of centrioles surrounded by a proteinaceous matrix that docks and activates {gamma}-tubulin complexes ({gamma}TuCs) to nucleate microtubules for spindle assembly. During mitotic entry, phosphorylation at centrosomes remodels CDK5RAP2 family matrix proteins to generate {gamma}TuC docking sites. We address the mechanism of this conversion using C. elegans SPD-5 as a model. We show that SPD-5 contains two regions, PRGB1 and PRGB2, that are each sufficient for Polo-Like Kinase 1 (PLK1) phosphorylation-regulated {gamma}TuC binding. We define key phosphosites in each region and uncover autoinhibition mediated by interactions within and between them. PRGB2 is dimeric and requires {gamma}TuCs containing the Mozart family microprotein MZT-1 for binding, whereas PRGB1 is monomeric and binds independently of MZT-1. Our results support PLK1 phosphorylation inducing a conformational change that enables MZT-1-dependent PRGB2 binding, which in turn relieves PRGB1 inhibition. Such a multi-step mechanism would ensure robust spindle assembly by restricting microtubule nucleation in space and time.

cell biology↗

bioRxiv2025

The Critical and Unexpected Role of a Methyl Group in Interleukin-17A Inhibitors

Interleukin-17 (IL-17) is a pro-inflammatory cytokine primarily secreted by Th17 cells. It plays a crucial role in the bodys immune defense against fungal and bacterial pathogens. However, an imbalance in IL-17 production can contribute to the development of autoimmune and inflammatory disorders. Therapeutic strategies targeting IL-17, such as blocking antibodies like secukinumab (Cosentyx), have been successfully developed. These antibodies are currently employed in the treatment of various conditions, including psoriasis, psoriatic arthritis, and ankylosing spondylitis. More recently, a small molecule inhibitor of IL-17, LY3509754, progressed to clinical trials but was halted during Phase 1 due to unfavorable hepatotoxicity. Two derivatives, compounds 7 and 8, did not advance to clinical trials due to safety concerns. These three compounds (7, 8, and the original lead compound, presumably implied) share a common difluoro substituent, which was hypothesized to be the cause of the observed safety issues. In subsequent structure-activity relationship (SAR) studies, replacing the difluoro substituent with a single methyl group (resulting in compound 9) unexpectedly led to a significant improvement in cellular activity. Furthermore, compound 9 exhibited a very low unbound fraction and reduced liver distribution, ultimately translating to high in vivo efficacy with a sufficient safety margin. This seemingly minor methyl substitution transformed the compound into a highly promising preclinical candidate (compound 9), now slated for further development. Co-development inquiries are welcome. Please contact us at enan1@dcpc.com. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=76 SRC="FIGDIR/small/680113v2_ufig1.gif" ALT="Figure 1"> View larger version (13K): org.highwire.dtl.DTLVardef@3f31adorg.highwire.dtl.DTLVardef@d6873forg.highwire.dtl.DTLVardef@494af7org.highwire.dtl.DTLVardef@1d8b7eb_HPS_FORMAT_FIGEXP M_FIG C_FIG

pharmacology and toxicology↗

bioRxiv2025

Cultivation and genomic characterisation of novel methanogens from a desert biocrust

Methanogens are strictly anaerobic archaea capable of energy conservation by methane production, yet their presence in oxic and arid environments challenges existing paradigms. In this study, we enriched and genomically characterised seven methanogenic cultures from desert biocrusts, affiliated with the genera Methanobacterium, Methanosarcina, and Methanocella. Six of these new cultures represent new species. Nonetheless, phylogenomic analyses revealed close genetic relationships with organisms from anoxic environments, indicating the absence of an evolutionary distinction. Comparative genomics exposed diverse though non-unique repertories of antioxidant (e.g. catalase, superoxide dismutase and desulfoferrodoxin), and desiccation-resistance genes (including genes for maintaining osmotic pressure and repair of cell wall and membrane), with Methanobacterium spp. possessing the lowest gene abundance and diversity for oxygen and desiccation tolerance. Nevertheless, the occurrence of a Class I methanogen such as Methanobacterium in arid soils challenges the notion that members of this class are less oxygen tolerant than Class II. Pangenome analysis further uncovered unique genes enriched in membrane-associated functions and potentially non-functional stress-related genes. Via a global metagenomic survey, we find that methanogens are underdetected in dryland soils, likely due to sequencing depth limitations. Our findings highlight previously overlooked methanogen diversity and ecological plasticity in oxic and desiccated habitats, and emphasise the need for further studies to elucidate their survival strategies.

microbiology↗

bioRxiv2025

O-mannose glycosylations influence E-cadherin functional interactions

Cadherins are plasma membrane proteins that play critical roles in maintaining cell-cell adhesion and modulating cell signaling during development. Their functions are mediated by extracellular cadherin (EC) domains, which facilitate adhesive interactions and enable the formation of cis- and trans assemblies at adherens junctions and desmosomes. EC domains adopt a characteristic immunoglobulin-like fold composed of seven {beta}-strands (A-G) and are modified by N -linked and O -linked glycosylations, including O -linked mannose monosaccharides (O -Man) on conserved serine and threonine residues of B- and G-strands. O -Man glycosylations on EC domains are catalyzed by the TMTC1-4 enzymes, with different TMTC enzymes modifying B- or G-strands. Given the site-specific deposition of O -Man glycans by dedicated enzymes and the central role of EC domains in cadherins functions, we hypothesized that these PTMs may fine-tune cellular adhesion and otherwise contribute to diverse physical interactions that involve cadherins. To test these hypotheses, we assayed for changes in protein-protein interactions formed with epithelial (E)-cadherin in model cells where O -Man were genetically ablated. Herein, we report O -Man-dependent E-cadherin (CDH1) protein interactions, revealed by affinity proteomics, and we orthogonally validate an altered association between CDH1 and CDH3 (P-cadherin). We show different interactomic changes associated with O -Man ablation on B- vs. G-strands, highlighting the importance of these PTMs in CDH1-associated interaction. These findings provide new insights into how O -Man regulates CDH1-dependent protein complexes.

cell biology↗

bioRxiv2025

Lessons from a gene knockout mouse model: no phenotypes induced by deletion of the TPR4 domain of Ttc22

The TTC22 gene encodes a protein containing seven tetratricopeptide repeats (TPRs), which mediate protein-protein interactions as chaperones. We previously reported that the level of TTC22 transcript variant 1 (TTC22v1) was downregulated in human colon adenocarcinoma (COAD) and that TTC22 upregulated m6A-mediated WTAP and SNAI1 expression via the TTC22-RPL4 interaction and subsequently promoted COAD metastasis. Thus, a commercially available C57BL/6N mouse model in which the Ttc22 exon 2&3 encoding the TPR4 (equal to the human TTC22 TPR3) domain was knocked out via CRISPR-Cas9 was used to evaluate the contribution of Ttc22 to the development of mice and COAD. To determine the status of Ttc22 expression in Ttc22 knockout mice, we prepared a rabbit polyclonal antibody against the mouse Ttc22 protein, which could bind both wild type Ttc22 and TPR4-deleted Ttc22 proteins overexpressed in HEK293T cells, as determined by Western blot analysis. Ttc22 proteins were detected in colon tissue samples from wild-type mice and Ttc22 hemi-knockout (Ttc22 -/+) mice but not in those from fully Ttc22 knockout (Ttc22-/-) mice. Unfortunately, the long-term observation results demonstrated that Ttc22 knockout (KO, including Ttc22-/+ or Ttc22-/-) did not affect the body weight, development, fertility, or spontaneous tumor incidence of male or female mice. No differences in the incidence of AOM/DSS-induced COAD were observed between these mouse groups, although Ttc22 deletion partially resulted in the upregulation of genes related to the host adaptive response to inflammation in the colon mucosa. In conclusion, no phenotypes were induced by Ttc22 inactivation in C57BL/6N mice. HighlightsO_LIKnockout of Ttc22 exons 2 and 3 completely disrupted gene expression. C_LIO_LIKnockout of Ttc22 does not affect the development of C57BL mice. C_LIO_LIKnockout of Ttc22 does not affect the induction of mouse colon cancer by AOM/DSS. C_LI

molecular biology↗

bioRxiv2025

Phosphorylation-inducing chimera rewires oncogenic kinase to trigger apoptosis

The active sites electric field is integral to enzymatic catalysis (e.g., substrate recognition) and nature employs charge-altering post-translational modifications (e.g., phosphorylation) to perturb this electric field and regulate enzymes. A chromosomal translocation converts Abelson kinase (ABL) to BCR-ABL, whose hyperactivity drives several cancers. Here, we developed a small molecule, BRD8833, that induces BCR-ABL phosphorylation, which perturbs its active sites electric field with loss of hyperactivity. Unlike "occupancy-driven" inhibitors that require stoichiometric concentrations, BRD8833 operates through an event-driven, substoichiometric mechanism by inducing proximity between two BCR-ABL molecules to trigger the inhibitory phosphorylation and selective apoptosis of BCR-ABL-dependent cancer cells. Furthermore, BRD8833 is effective against other oncogenic ABL fusions or clinically observed resistance mutations, including those to occupancy-driven drugs with the same binding site as BRD8833, suggesting differences in their resistance mechanisms. These studies lay the foundation for electric-field and "event-driven" modalities to control hyperactive enzymes with orthogonal resistance mechanisms to occupancy-driven drugs. GRAPHICAL ABSTRACT (TOC) O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=197 SRC="FIGDIR/small/659082v2_ufig1.gif" ALT="Figure 1"> View larger version (48K): org.highwire.dtl.DTLVardef@1607a40org.highwire.dtl.DTLVardef@fa10deorg.highwire.dtl.DTLVardef@1698232org.highwire.dtl.DTLVardef@1e2e0f1_HPS_FORMAT_FIGEXP M_FIG C_FIG

synthetic biology↗

bioRxiv2025

Phosphorylation-inducing molecules for regulating dynamic cellular processes

Dynamic cellular processes often employ protein phosphorylation for rapid information transfer within and between cells. Phosphorylation-inducing chimeric small molecules (PHICS) have been developed for targeted protein phosphorylation by on-demand inducing a kinase-protein pairing. However, widespread application of PHICS has been limited as previously reported PHICS that recruited AMP-activated protein kinase (AMPK) required serum starvation and target protein overexpression, recruited only a few of the potential AMPK complexes, and exhibited poor dose- and temporal control. Herein, we report an AMPK PHICS platform that operates under physiological conditions (i.e., no serum starvation or target overexpression), recruits multiple AMPK complexes, and can induce target protein phosphorylation with dose and temporal control. We demonstrated the utility of this platform for controlling phosphorylations that underlie two dynamic cellular processes, namely oncogenic signaling and phase separation. An AMPK PHICS directed against Brutons Tyrosine Kinase (BTK), which is a driver of several B cell malignancies, was effective at inducing the death of drug-resistant cancer cells. Here, PHICS induced inhibitory phosphorylations on BTK and attenuated its oncogenic pathway. Phosphorylation of Liprin-3 induces phase separation in neurons and is critical for neurotransmitter release. Using AMPK PHICS that phosphorylated Liprin-3, we induced Liprin-3 phase separation with dose and temporal control. We envision this PHICS platform to find utility in inducing and controlling protein phosphorylations for basic research and biomedicine. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=102 SRC="FIGDIR/small/652895v1_ufig1.gif" ALT="Figure 1"> View larger version (24K): org.highwire.dtl.DTLVardef@16bbb20org.highwire.dtl.DTLVardef@1ca5267org.highwire.dtl.DTLVardef@1e805d5org.highwire.dtl.DTLVardef@1d6ec22_HPS_FORMAT_FIGEXP M_FIG C_FIG

biochemistry↗

bioRxiv2025

An embryonic artery-forming niche reactivates in pulmonary arterial hypertension

Developmental programs that orchestrate cell fate and tissue architecture during organogenesis can cause disease when reactivated in adults. Here we identify a population of endothelial cells (ECs) defined by the pioneer factor early B cell factor 1 (EBF1) that controls both pulmonary artery (PA) morphogenesis and pulmonary arterial hypertension (PAH). During embryonic development, the PA emerges from an endothelial niche harbored within the vascular plexus, where Aplnr+ endothelial progenitors give rise to both arterial ECs and EBF1+ ECs. Rather than directly incorporating into the PA intima, EBF1+ ECs control the branching and maturation of the PA tree through paracrine vasculotrophic signals that direct plexus expansion, arterialization, and mural cell recruitment. Although essential for development, most EBF1+ ECs disappear upon completion of PA morphogenesis. In adult PAH, vascular injury reactivates this developmental program: normally quiescent general capillary ECs re-enter the cell cycle and differentiate into arterial ECs and EBF1+ ECs, reconstituting this artery-forming niche in a maladaptive reprise. Unlike their transient embryonic counterparts, EBF1+ ECs persist within neointimal lesions and express vasculotrophic signals associated with pathological PA remodeling. Capillary-restricted Ebf1 induction combined with endothelial injury recapitulates this program, driving neo-arterialization, neointimal formation, and severe PAH. Conversely, endothelial-targeted AAV-mediated Ebf1 knockdown achieves complete protection in a preclinical model of disease, demonstrating that endothelial EBF1 is necessary for PAH pathogenesis. These findings demonstrate that reactivation and persistence of a transient embryonic artery-forming niche in adulthood can promote pathological vascular remodeling and PAH.

developmental biology↗

bioRxiv2025

Dimethyl fumarate reprograms cervical cancer cells to enhance antitumor immunity by activating mtDNA-cGAS-STING pathway

BackgroundCervical cancer (CC) remains a significant global health challenge for women, especially in advanced stages where effective treatments are limited. Current immunotherapies, including PD-1/PD-L1 blockades and adoptive T cell therapies, show limited response rates and durability. Dimethyl fumarate (DMF), an FDA-approved drug for autoimmune diseases, has demonstrated that it might exhibit direct antitumor activity in several cancers. However, its influence on anti-tumor immunity and its function in CC remain poorly understood. This study aims to investigate the therapeutic potential of DMF in CC models and elucidate its underlying mechanisms of action. MethodsCC cell lines and mouse models were treated with DMF. Transcriptional level changes in cervical cancer cells following DMF treatment were analyzed by RNA-seq. Mitochondrial DNA (mtDNA) release, and cGAS-STING activation were assessed via qPCR, immunofluorescence, immunoblotting and ELISA. CD8+ T cell recruitment was analyzed by flow cytometry. Combinatorial therapies (DMF + anti-PD-1/TILs) were tested in syngeneic or patient-derived xenografts (PDX) models. ResultsDMF treatment induces mitochondrial dysfunction in tumor cells, resulting in the release of mtDNA into the cytosol. The cytosolic mtDNA activates the cGAS-STING-TBK1 pathway and type I interferon response, leading to the secretion of CCL5 and CXCL10, thereby enhancing CD8 T cell infiltration. Additionally, DMF exhibits synergistic effect with PD-1 blockade in murine CC model, and can enhance the therapeutic efficacy of adoptively transferred T cells toward CC patient-derived xenografts model. ConclusionThis work elucidated that DMF reprograms CC cells to activate the mtDNA-cGAS-STING pathway, fostering a chemokine-rich microenvironment that recruits CD8+ T cells. Its synergy with PD-1 blockade or TIL therapy underscores its potential as an immunomodulatory adjuvant. These findings suggest that DMF holds promise as a novel immunotherapeutic strategy for improving clinical outcomes in CC.

immunology↗

bioRxiv2025

DNA Methylation Dynamics of Dose-dependent Acute Exercise, Training Adaptation, and Detraining

Exercise and diet are direct physical contributors to human health, wellness, resilience, and performance1-5. Endurance and resistance training are known to improve healthspan through various biological processes such as mitochondrial function6-8, telomere maintenance9, and inflammaging10. Although several training prescriptions have been defined with specific merits 1,10-20, the long-term effects of these in terms of their molecular alterations have not yet been well explored. In this study, we focus on two combined endurance and resistance training programs: (1) traditional moderate-intensity continuous endurance and resistance exercise (TRAD) and (2) a variation of high-intensity interval training (HIIT) we refer to as high intensity tactical training (HITT), to assess the dynamics of DNA methylation (DNAm) in blood and muscle derived from males (N=23) and females (N=31), over a 12-week period of training followed by a 4-week period of detraining, sampled at pre-exercise and acute time points, totaling 528 samples. Due to its rapid responsiveness to stimuli and its stability, DNAm has been known to facilitate regulatory cascades that significantly affect various physiological processes and pathways. We find that several thousand differentially methylated regions (DMRs) associated with acute exercise in blood, many of which are shared across males and females. This trend is reversed when comparing the baseline (pre-exercise) time points or post-exercise timepoints at the untrained state with those at the post-conditioned state. Here, muscle shows majority of DNAm changes, with most of those being unique. We also find several hundred "memory" DMRs in muscle that maintain the gain or loss of methylation after four weeks of inactivity. Comparing phenotypic measurements, we find specific DMRs that correlate significantly with mitochondrial function and myofiber switching. Using machine learning, we select a subset of DMRs that are most characteristic of training modalities, sex and timepoint. Most of the DMRs are enriched in pathways associated with immune function, cell differentiation, and exercise adaptation. These findings reveal mechanisms by which exercise- and training-induced epigenetic changes alter immune surveillance, mitochondrial function, and inflammatory response, and underscore the relevance of epigenetic plasticity to health monitoring and wellness.

genomics↗