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Zhou, J.

Publications and source records attributed to Zhou, J..

At least 91 records · Page 5Linked to original sources

Co-evolution of Oncogenic KRAS Signaling and LILRBhigh Macrophages Drives Pancreatic Cancer Recurrence

Pancreatic ductal adenocarcinoma (PDAC) frequently recurs after surgical resection, indicating that residual disease is sustained by coordinated tumor-microenvironment interactions. To define the biological basis of recurrence, we leverage large-scale clinical data from 2,710 patients, deeply characterized multi-omics profiling (whole-exome, bulk RNA, and single-nucleus sequencing) of 36 matched primary and locally recurrent PDACs, an in-house multiplex spatial imaging cohort of 190 patients, and extensive public datasets. Recurrent tumors were characterized by increased KRAS mutant allele dosage and reinforced KRAS signaling, accompanied by expansion of basal-like malignant cell states. In parallel, we identified an immunosuppressive macrophage population marked by high LILRB expression that spatially co-localized with KRAS-activated tumor cells. Functional studies showed that LILRB4+ macrophages enhanced tumor cell plasticity and progression, whereas inhibition of macrophage LILRB4 suppressed these phenotypes. Notably, a first-in-class human anti-LILRB4 antibody reduced macrophage-driven tumor traits, and dual targeting of KRAS signaling and LILRB4 achieved superior tumor control in macrophage-containing mouse models. These findings reveal a co-evolved tumor-immune niche underlying PDAC recurrence and nominate the KRAS-LILRB4 axis as a therapeutic vulnerability.

cancer biology↗

Metformin Stabilizes the Abdominal Aorta in Aneurysm by Restoring VSMC Mitochondrial Homeostasis via the AMPK-SIRT1-PGC-1α Axis

BACKGROUNDAbdominal aortic aneurysm (AAA) is a life-threatening condition with >80% mortality upon rupture and no effective pharmacotherapy available. Despite epidemiological evidence linking metformin use to reduced AAA progression, its mechanism remains elusive. Notably, peroxisome proliferator-activated receptor {gamma} coactivator 1 (PGC-1, encoded by Ppargc1a) is downregulated in human AAA, yet its functional role in metformins protection is unknown. METHODSWe employed porcine pancreatic elastase (PPE)-induced murine AAA, VSMC-specific Ppargc1a knockout (Ppargc1aVSMC-KO), primary VSMC senescence models, and pharmacological inhibition (Compound C for AMPK; Ex-527 for SIRT1) to define the AMPK-SIRT1-PGC-1 axis. RESULTSMetformin significantly inhibited AAA expansion, suppressed VSMC senescence (p53/p21{downarrow}, SA-{beta}-gal{downarrow}), and preserved contractile phenotype (SMTN{uparrow}, IL-6/TNF-{downarrow}). Crucially, all benefits were abrogated in Ppargc1aVSMC-KO mice, which exhibited accelerated aneurysm growth, mitochondrial fragmentation, ATP depletion, and ROS accumulation. Mechanistically, metformin activated AMPK/SIRT1 to upregulate PGC-1; AMPK or SIRT1 inhibition blocked this cascade and reversed protection. CONCLUSIONMetformin restrains AAA by restoring VSMC mitochondrial homeostasis via the AMPK/SIRT1[->]PGC-1 axis, positioning PGC-1 as a non-redundant, cell-autonomous guardian against vascular degeneration. These findings provide a mechanistic foundation for repurposing metformin and developing PGC-1-targeted therapies in AAA.

cell biology↗

Kindlin-2-Moesin interaction orchestrates sprouting angiogenesis via modulating endothelial membrane mechanics and VEGF signaling

Membrane mechanics play a crucial role in cellular signaling and fate determination, yet their impact on angiogenesis remains poorly understood. Here, we identify Kindlin-2 as a key regulator of sprouting angiogenesis via regulating endothelial membrane tension through its interaction with Moesin, a crucial linker protein between the cell membrane and the actin cortex. Mechanistically, Kindlin-2 binds to the N62 residue of Moesin, limiting its overactivation and maintaining proper membrane tension to facilitate VEGFR2 endocytosis and downstream signaling. Using both developmental and pathological models, we demonstrate that the interaction of Kindlin-2 and Moesin is enhanced in high angiogenic conditions, and endothelial Kindlin-2 deletion reduces angiogenesis. Furthermore, mutation of Moesin at N62 phenocopies the effects of Kindlin-2 loss. Together, these findings uncover a previously unrecognized mechanism linking membrane tension regulation to angiogenesis and provide new insights into targeting the Kindlin-2-Moesin axis for therapeutic intervention in neovascular diseases.

developmental biology↗

Gene synteny and translational coupling of sctS and sctT facilitate assembly of the unique helical T3SS export apparatus in Salmonella Typhimurium

Virulence-associated type III secretion systems (T3SS) are employed by many gram-negative pathogens to translocate effector proteins into hosts. These nanomachines are composed of cytoplasmic components, a needle complex base, housing the export apparatus and anchoring the machine in the bacterial cell envelope, a needle filament, and a translocon that penetrates the host membrane. Assembly of the T3SS is a hierarchical process, which is initiated by coordinated association of the five subunits comprising the export apparatus, SctR, SctS, SctT, SctU, and SctV, in the bacterial inner membrane. In this study, we report that proper assembly of this uniquely helical export apparatus is fine-tuned by the genetic organization of the export apparatus genes in Salmonella Typhimurium. The sctS mRNA harbors a stem-loop structure which conceals the Shine-Dalgarno sequence of sctT from recognition by a ribosome. sctT translation is only possible upon melting of the stem-loop by a sctS-translating ribosome. This mechanism translationally couples sctS and sctT. We show that this strict regulation prevents uncontrolled overexpression of SctT and its assembly into futile multimers that disrupt export apparatus assembly and reduce pathogen fitness. Based on the strong synteny of T3SS export apparatus genes and their highly conserved unique structure, also among closely related bacterial flagella, similar mechanisms are likely needed to enable a tightly regulated and stoichiometric assembly process of these molecular machines in general.

microbiology↗

TRIM32-UBQLN2-p62 axis promotes TDP-43 inclusion formation and amyloid aggregation through shuttle condensates

Aberrant protein aggregation is a hallmark of amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD), which share overlapping genetic and pathological features. Similar aggregates are increasingly recognized in Alzheimers disease (AD) and limbic-predominant age-related TDP-43 encephalopathy (LATE). However, it remains unclear whether a shared molecular pathway drives this pathological aggregation. Here, we report that the E3 ubiquitin ligase TRIM32, together with the shuttle factor UBQLN2 and the autophagy adaptor p62/SQSTM1, form condensates that depend on E3 ligase activity and a network of intermolecular interactions. These condensates act as scaffolds that capture UBQLN2 client proteins, including TDP-43 and ANXA11, and modulate their mobility. A unique hydrophobic loop within TRIM32s substrate-binding domain mimics low-complexity motifs in ANXA11 and TDP-43, enabling selective retention via competitive binding mediated by UBQLN2 STI1 domain. Moreover, TRIM32 condensates promote amyloid aggregation of TDP-43, an effect that is exacerbated by pathogenic UBQLN2 mutation. In brains from individuals with diverse neurodegenerative diseases, TRIM32 co-localizes with pathological phospho-TDP-43 (pTDP-43) inclusions, supporting a model in which TRIM32-driven condensates function as selective proteostasis sorting compartments that broadly contribute to TDP-43 proteinopathy.

neuroscience↗

Characterization of the Gut Microbiota and Serum Metabolomics in Patients with Type 2 Diabetes Mellitus and Newly Diagnosed Acute Coronary Syndrome

Biomarkers for the early identification of acute coronary syndrome (ACS) risk remain inadequately investigated, particularly in patients with type 2 diabetes mellitus (T2DM), for whom timely clinical intervention may substantially enhance prognostic outcomes. The gut microbiota and serum metabolites may serve as pivotal mediators in the occurrence and progression of ACS among patients with T2DM, and whether these factors can be used for the precise discrimination of patients with T2DM complicated by ACS remains to be explored. Overall, 76 participants were enrolled (38 patients diagnosed with T2DM complicated by ACS and another 38 with T2DM without ACS). 16S rRNA sequencing combined with untargeted LC-MS metabolomics revealed a dysregulated gut-serum axis in patients with T2DM complicated by ACS: enrichment of proinflammatory microorganisms (Enterococcus spp.), reduction of butyrate producers (Butyricimonas spp.) and concomitant dysregulation of circulating lipid metabolites-upregulation of PC(16:0/9:0 (CHO)) and arachidonic acid alongside downregulation of cholesterol sulfate. By integrating multiomics data and applying various feature selection methods, we subsequently identified six key biomarkers. The final constructed combined model robustly distinguished patients with T2DM complicated by ACS from those with T2DM alone (AUC = 0.983), outperforming the other single omics models. Our study revealed that the gut microbiota and related serum metabolites serve as key mediators in the onset and progression of ACS among patients with T2DM, and demonstrated their potential value as noninvasive biomarkers for the early diagnosis of T2DM complicated by ACS. Clinical PerspectiveO_ST_ABSWhat Is New?C_ST_ABSWe combined 16S rRNA sequencing with untargeted LC-MS metabolomics to dissect the gut-serum axis in patients with T2DM complicated by newly diagnosed ACS. We identified distinct gut microbial and serum metabolic signatures that distinguish ACS progression within the T2DM population. A multiomics classifier integrating clinical, microbial, and metabolic variables achieved robust diagnostic performance (AUC = 0.983) and outperformed single omics models. What Are the Clinical Implications?Integrated multiomics biomarkers facilitate the early identification of ACS progression in patients with T2DM, offering novel avenues for precision prevention, dynamic clinical surveillance, and individualized therapeutic strategies. Dysregulations of the gut microbiota and serum metabolome may play an important role in the development and progression of ACS in patients with T2DM.

microbiology↗

A spatiotemporal immune atlas of subarachnoid hemorrhage from single-cell and spatial transcriptomics

Background and PurposeSubarachnoid hemorrhage (SAH) triggers a complex immune response that critically influences early brain injury (EBI) and long-term outcomes. However, the precise spatiotemporal dynamics and heterogeneity of immune cell infiltration and microglial reprogramming remain poorly understood. We aimed to construct a high-resolution immune atlas to delineate cell states, lineage trajectories, and spatial niches following SAH. MethodsWe integrated single-cell RNA sequencing (scRNA-seq) of CD45+ immune cells with spatial transcriptomics (ST) in a murine endovascular perforation SAH model. Immune landscapes were profiled at 24 hours (acute phase) and 72 hours (subacute phase) post-injury, compared with sham controls. Advanced bioinformatics integrated transcriptional signatures with spatial localization to map macrophage, neutrophil, and microglial dynamics. ResultsOur atlas reveals a coordinated immune transition from acute inflammation to reparative processing. We identified five macrophage, four neutrophil, and eight microglial subsets with distinct spatiotemporal patterns. Notably, we discovered a SAH-specific inflammatory microglial population (MG_03; Spp1+/Lpl+) that clusters at the rupture site during the acute phase. This subset is transcriptionally distinct from disease-associated microglia (DAM) in other neurodegenerative conditions. Trajectory analysis suggests MG_03 acts as a signaling hub for immune recruitment before transitioning toward proliferative and reparative states (MG_06-08) that disperse into the parenchyma by 72 hours. ConclusionsThis study provides the first comprehensive spatiotemporal immune atlas of SAH, highlighting the distinct role of the Spp1+ MG_03 subpopulation in early injury sensing. These findings offer a roadmap for identifying precise therapeutic windows and targeting specific immune subsets to mitigate EBI. Graphical AbstractExperimental workflow for single-cell RNA sequencing (scRNA-seq) and spatial transcriptomics (ST) in a mouse SAH model induced by endovascular perforation. Brain tissue from the ipsilateral (injured) hemisphere was collected from sham and at 24 h and 72 h post-SAH. For scRNA-seq, CD45 immune cells were isolated prior to library preparation. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=124 SRC="FIGDIR/small/703421v1_ufig1.gif" ALT="Figure 1"> View larger version (39K): org.highwire.dtl.DTLVardef@4a1bc9org.highwire.dtl.DTLVardef@16664c4org.highwire.dtl.DTLVardef@1619725org.highwire.dtl.DTLVardef@a0d34_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

Regulation of BCL11A DNA binding and expression in human erythrocyte precursor HUDEP-2 cells

BCL11A is a transcription factor crucial for neurodevelopment and hematopoiesis. It regulates the developmental switch from fetal hemoglobin (HbF) to adult hemoglobin and is a major therapeutic target for sickle cell disease and {beta}-thalassemia. BCL11A exists in multiple isoforms, including the L isoform (containing a single two-finger ZF2-3 DNA-binding domain) and the XL isoform (containing two arrays: the two-finger ZF2-3 and the three-finger ZF4-6). We used three approaches to investigate BCL11A functions. First, we examined DNA recognition by BCL11A, which preferentially binds the short 6-bp DNA motif TGNCCA. ZF4-6 recognizes all four variants of this motif with distinct strand-specific interactions: TGTCCA on the top strand, TG(A/C)CCA on the complementary strand, and the palindromic TGGCCA on either strand. ZF2-3 also binds TGTCCA from the top strand, featuring a unique thymine interaction by ZF2 Phe388. Motif multiplicity within BCL11A binding sites may promote BCL11A oligomerization by enabling multiple ZF arrays to engage DNA simultaneously. Second, we treated HUDEP-2 cells (which express adult hemoglobin) with inhibitors targeting three epigenetic silencing marks - DNA methylation, histone H3 lysine 9 methylation or H3 lysine 27 methylation. All treatments, individually or in combination, increased HbF expression to varying degrees. Notably, FTX6058 markedly reduced BCL11A transcription and translation (likely via effects on LIN28B), while EML741 caused a partial reduction. Third, we screened 213 pomalidomide- and lenalidomide-derived compounds and quantified proportions of HbF+ cells by flow cytometry. Effects of four compounds were analyzed by protein mass spectrometry. Although BCL11A levels themselves were unchanged, all four compounds selectively decreased levels of known pomalidomide targets, with consistently decreased levels of the zinc-finger proteins IKZF1 and ZFP91. Together, our studies clarify how BCL11A recognizes DNA, how its expression can be modulated epigenetically, and how small-molecule degraders influence its regulatory network, providing new avenues for HbF reactivation therapies.

biochemistry↗

The genetic repertoire of the deep sea: from sequence to structure and function

The deep sea as the largest and maybe most hostile environment on Earth is still underexplored especially regarding its genetic repertoire. Yet, previous work has revealed significant habitat-specific deep-sea biodiversity. Here, we present an integrated deep-sea genetic dataset comprising 502 million nonredundant genes from 2,138 samples and 2.4 million predicted structures, and used it to link specific protein structures with genetic variants associated with life in the deep sea and to assess their biotechnology potential. Combining global sequence analysis with biophysical and biochemical measurements revealed unprecedented sequence diversity, yet substantial structural conservation of proteins. Especially proteins involved in replication, recombination, and repair were identified to be under rapid evolution and with specialized properties. Among these, a structurally divergent helicase exhibited advantages in controlling nanopore sequencing speed. Thus, our work positions the deep sea as a unique evolutionary engine that generates and hosts genetic diversity and bridges genetic knowledge with biotechnology.

bioinformatics↗

JAK-STAT Pathway Heterogeneity Governs Immunotherapy Response in Breast Cancer

The JAK-STAT pathway (JSP) is a well-known oncogenic cascade; however, recent clinical trials have detected JSP upregulation in breast cancer following anti-PD1 immunotherapy. This paradoxical observation warrants further investigation into JSPs intercellular heterogeneity, tumor dynamics, molecular mechanisms, and clinical implications for immunotherapy. JSP expression showed dynamic shifts during breast cancer progression, with higher levels in T cells and para-cancerous epithelial cells. In tumor cells, elevated JSP highly correlated with malignant phenotypes. JSP-high tumor cells overexpressed oncogenic pathways, while exhibiting increased immunosuppressive signaling via MIF-CD74 signaling axis. In T cells, higher JSP levels were associated with enhanced cytotoxic activity, improved differentiation, and reduced exhaustion, reflecting robust anti-tumor immunity. Analysis of immunotherapy datasets revealed that higher JSP levels were associated with improved responses towards PD-1 inhibitors, particularly in triple-negative breast cancer (TNBC) patients, with JSP serving as a predictive biomarker for immunotherapy sensitivity. As a key JSP component, STAT4 exerts dual roles in breast cancer: it drives tumorigenesis in malignant cells, sustains breast epithelial cell proliferation, and bolsters T cell anti-tumor functionality--while also acting as a highly accurate biomarker for predicting immunotherapy response. This indicates that JSP targeting demands a nuanced approach: broad inhibition may impair anti-tumor immunity, and optimized therapeutic strategies paired with precise biomarkers are critical to maximize JSPs utility in breast cancer immunotherapy. Our findings highlight JSPs functional heterogeneity in epithelial, tumor, and T cells, with high JSP activity correlating with enhanced immunotherapy efficacy in breast cancer. Graphic Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=182 SRC="FIGDIR/small/703506v3_ufig1.gif" ALT="Figure 1"> View larger version (30K): org.highwire.dtl.DTLVardef@c3a850org.highwire.dtl.DTLVardef@15f2f0borg.highwire.dtl.DTLVardef@99065org.highwire.dtl.DTLVardef@1e6eb6c_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

Oxaloacetate damages mitochondria by perturbing MIC60-dependent membrane remodeling

Mitochondria catabolize nutrients by generating sequentially-ordered organic acid intermediates that are oxidized through the tricarboxylic acid cycle. Pathogenic accumulation of metabolic organic acids manifests as devastating organic acidemias/acidurias and other severe diseases, but the underlying mechanisms are largely unknown. Using unbiased C. elegans genetic screening, we here reveal that mutations in the phosphoenolpyruvate carboxykinases PCK-1 and PCK-2 cause buildup of oxaloacetate, a key tricarboxylic acid cycle intermediate, leading to severe mitochondrial damage. Depletion of mitochondrial GOT-2.1 or GOT-2.2, which catalyze oxaloacetate conversion to aspartate, also causes oxaloacetate accumulation and defective mitochondria with disrupted cristae. We demonstrate that oxaloacetate binds the MICOS complex subunit CHCH-3/MIC19 and inhibits its function of promoting IMMT-1/MIC60-dependent membrane shaping and remodeling. In mammalian cells, aberrant OAA buildup similarly causes mitochondrial impairment through MIC19 and MIC60. These findings not only provide important mechanistic insights into mitochondrial damage in the context of defective oxaloacetate metabolism, but also suggest therapeutic strategies for oxaloacetate-related mitochondriopathies.

cell biology↗

CCycDB: an integrative knowledgebase to fingerprint microbially mediated carbon cycling processes

Microorganisms play essential roles in mediating biogeochemical cycling of carbon across Earths ecosystems. Understanding the processes and underlying mechanisms for microbially mediated carbon cycling is therefore critical for advancing global ecology and climate change research. To comprehensively depict these complex biogeochemical processes, we developed CCycDB, a knowledge-based functional gene database, to accurately fingerprint microbially-mediated carbon cycling pathways and gene families, particularly from shotgun metagenomes. The CCycDB database comprises 4,676 gene families classified into six major functional categories, further structured into 45 level-1 and 188 level-2 sub-categories, encompassing a total of 10,991,724 high-quality reference sequences. Validation using both synthetic and real-world datasets demonstrated that CCycDB outperforms existing orthology databases in terms of accuracy, coverage and specificity. By directly targeting carbon-cycling functional gene families, CCycDB provided promising routines to reconstruct both functional gene and taxonomic profiles associated with microbially mediated carbon cycling. Application of CCycDB to shotgun metagenomes from diverse and complex ecosystems revealed pronounced habitat-specific differences in carbon cycling processes and their associated microbial taxa. Collectively, CCycDB provides a powerful and reliable tool for profiling carbon cycling processes from both functional and taxonomic perspectives in complex ecosystems. CCycDB is accessible at https://ccycdb.github.io/. Impact StatementThe microbially mediated carbon cycling processes are the most complex biogeochemical processes in the Earths biosphere, playing profound regulatory roles on global climate changes. A key bottleneck in linking microbial communities to global change is the lack of integrated tools for comprehensive carbon cycle profiling. Here, we present CCycDB, a tool that serves a dual purpose--first being a reference database that obtains functional gene and taxonomic profiles and functioning as a customized routine for efficiently aligning sequences and querying associated functional information. CCycDB enables researchers to accurately link microbial community dynamics to carbon cycling and transforming pathways, thereby advancing integrated global change studies with microbes and ecological research via complex metagenomic datasets.

microbiology↗

Mechanism study on lactic acid promoting intervertebral disc degeneration by regulating senescence and DNA damage of cartilage endplate stem cells

Intervertebral disc degeneration, a leading cause of low back pain with incompletely elucidated molecular mechanisms, was studied via integrated in vivo/vitro approaches. This study first reveals that lactic acid accelerates intervertebral disc degeneration by inducing cartilage endplate stem cells senescence and DNA damage, thereby activating the P16/P21/P53-centered senescence pathway. In a rat tail vertebra puncture-induced intervertebral disc degeneration model, degenerated discs exhibited increased lactic acid levels, narrowed intervertebral spaces, and disrupted nucleus pulposus structure (P<0.05). In vitro, 0/2/6/10 mM lactic acid dose-dependently suppressed cartilage endplate stem cells viability (10 mM group: 15.7% of the control), elevated intracellular reactive oxygen species (ROS, 2.8-fold relative to the control), induced G0 cell cycle arrest (10 mM group: 85.63%), reduced EdU-positive cells (8.62%), and increased {beta}-galactosidase-positive cells (10 mM group: 33.06%) and {gamma}-H2AX foci (all P<0.01).Molecularly, lactic acid significantly upregulated P16 (2.1-fold), P21 (3.1-fold), P53 (2.4-fold), and {gamma}-H2AX (1.8-fold). In vivo intervertebral disc injection confirmed a positive correlation between lactic acid concentration and intervertebral disc degeneration severity. This study clarifies lactic acids role in intervertebral disc degeneration via the "oxidative stress-cell cycle arrest-cellular senescence" axis, advancing understanding of intervertebral disc degeneration pathogenesis and providing a basis for targeted therapies against lactic acid metabolism.

cell biology↗

Interorganelle competition for linoleic acid underlies steatotic liver pathology

Lipid droplets (LDs) are traditionally viewed as protective organelles that sequester potentially cytotoxic lipids. However, whether and how LD biogenesis in pathological contexts actively rewires interorganelle lipid homeostasis to drive organelle dysfunction and disease progression remains unexplored. Here, we identify the adipocyte-enriched protein calsyntenin 3{beta} (CLSTN3B) as a critical promoter of metabolic dysfunction-associated steatotic liver disease (MASLD). CLSTN3B, an ER-LD contact protein previously shown to support LD maturation in adipocytes, is robustly induced in mouse hepatocytes by peroxisome proliferator-activated receptor {gamma} (PPAR{gamma}) in response to dietary caloric overload. CLSTN3B drives LD biogenesis and neutral lipid storage by stabilizing hemifusion-like ER-LD membrane bridges via its arginine-rich segment. These bridges preferentially recruit cone-shaped linoleoylated phosphatidic acid (PA), diverting linoleic acid (LA) into triacylglycerides (TAGs) rather than mitochondrial cardiolipin (CL), leading to disrupted cristae architecture, deficient ETC supercomplex assembly, elevated electron leak, and oxidative stress. Hepatocyte-specific CLSTN3B deletion impairs LD formation, reduces TAG accumulation, enhances fatty acid oxidation, restores CL maturation, and mitigates oxidative stress, collectively attenuating MASLD progression. Consistently, hepatic CLSTN3B expression correlates with fibrosis severity and progression in human MASLD. These findings position LDs as active regulators of interorganelle lipid partitioning and establish CLSTN3B as a key determinant of mitochondrial vulnerability, providing a general framework for how dysregulated organelle interfaces shape disease.

cell biology↗

AutoPELSA: an automated sample preparation system for proteome-wide identification of target proteins of diverse ligands

Protein-ligand interactions are fundamental to cellular function and drug discovery, and ligand-modification-free strategies have emerged as powerful tools for proteome-wide interrogation of these interactions. Among these, the peptide-centric local stability assay (PELSA) stands out for its high sensitivity. It uses a single digestion step to detect ligand-induced local stability shifts, enabling precise binding region localization and affinity estimation. However, manual PELSA workflows suffer from multiple labor-intensive steps that introduce variability and constrain throughput, limiting large-scale applications. To address these limitations, we developed AutoPELSA, an automated platform that streamlines the PELSA workflow including the limited proteolysis step and the following peptide separation step. AutoPELSA completes 96 samples in [~]4 h, enabling high-throughput analysis under native conditions. AutoPELSA reliably detected targets of both strong-affinity ligands (e.g., staurosporine, identifying 114 kinase targets) and low-affinity ligands, including -ketoglutarate (30 known targets). Furthermore, a mixed-ligand dose-response strategy enabled simultaneous determination of binding affinities for multiple ligand-protein interaction regions in a single experiment. Overall, AutoPELSA provides a scalable and modification-free platform for proteome-wide identification and affinity profiling of ligand-protein interactions.

molecular biology↗

Mitochondrial dsRNA: A Hidden Source of Immunogenic RNA in ADAR1 Deficiency

Double-stranded RNA (dsRNA) triggers immune responses during viral infections, but self-derived dsRNA can activate similar pathways. To prevent this, the body relies on mechanisms like ADAR1, an RNA-editing enzyme essential for immune regulation. Dysfunction of ADAR1 is linked to various diseases, yet the nature and role of dsRNAs accumulating in its absence remain unclear. Here, we identify mitochondrial dsRNA (mt-dsRNA), transcribed from the mitochondrial genome, as a major contributor to the endogenous dsRNA pool in ADAR1-deficient human and murine cells. We propose a "Draw-and-Release" model, where ADAR1 loss increases mitochondrial reactive oxygen species (mtROS), causing mt-dsRNA accumulation in the mitochondrial matrix ("Draw" phase) and its immune-activating release into the cytosol upon mitochondrial protein dysfunction ("Release" phase). This study highlights the importance of mitochondrial integrity in mitigating ADAR1-related pathologies.

cell biology↗

Meta-learning is expressed through altered prefrontal cortical dynamics

Learning where and when rewards like food and water are available is essential for survival1,2. In the simplest cases where resource availability is stable, animals can learn reward contingencies by integrating outcomes across repeated samples of each possible action. In more natural settings, however, reward availability is governed by structured higher-order rules such as depletion and repletion over time. To adapt flexibly to such changing environments, optimal choices require meta-learning wherein animals learn how to learn from external feedback, ultimately enabling them to infer the underlying reward structure from abstract, generalizable rules rather than relying solely on recent outcomes3,4. The existence of meta-learning in animal behavior is well established3-8, yet the neural circuits and computations that implement it remain poorly understood9-11. Here we investigated meta-learning using a spatial foraging task in which rats acquired a depletion-repletion rule that regulated reward availability, and carried out longitudinal, high-density recordings from the medial prefrontal cortex (mPFC). We show that meta-learning engages specific, systematic changes in mPFC neural dynamics that embed the learned rule and thereby alter how the network learns action values from reward outcomes. These dynamics are based on mixed coding of task structure and value in individual mPFC neurons. At the population level, this coding organizes into low-dimensional dynamical motifs that generalize across task conditions. As meta-learning progresses, these motifs are reshaped to instantiate both rule-guided inference of future states before outcome delivery and rule-based value updating during the outcome period. These results indicate that meta-learning sculpts pre-existing prefrontal dynamics to support the acquisition of new, generalizable reward-learning strategies.

neuroscience↗

CAR-T-drug conjugate against solid tumor

Chimeric antigen receptor (CAR)-T cell therapy has been clinically successful in hematologic cancers but faces challenges in solid tumors, primarily due to limited tumor infiltration, immunosuppressive tumor microenvironments (TME), and antigen heterogeneity. While combining CAR-T cell therapy with chemotherapy can enhance antitumor activity, this often leads to substantial systemic toxicity. In this study, we introduce CAR-T-drug conjugate (CAR-T-D-C), a new class of dual-functional therapeutics that effectively addresses these obstacles by integrating click chemistry for precise conjugation of cytotoxic agents onto antigen-specific CAR-T cells. By transforming the hostile TME into an ally, this approach facilitates localized delivery of cytotoxic payload directly to the tumor site, enhancing the overall effectiveness of CAR-T therapy in solid tumors. CAR-T-D-Cs with different CAR-T cell binders exhibit robust antitumor activity across diverse solid tumor models, including both human tumor xenografts and syngeneic models. Spatial transcriptomic studies reveals that CAR-T-D-C achieves improved CAR-T tumor infiltration and functional activation within the TME. Compared to conventional CAR-T therapy, CAR-T-D-C markedly enhances immune cell infiltration, augments effector functions, promotes antigen spreading, amplifies systemic immune responses, and improves overall anti-tumor immunity. CAR-T-D-C represents a versatile therapeutic concept that combines the potency of small molecule drugs and the specificity of CAR-T cells as a 2-in-1 immunochemotherapy for treatment of solid tumors.

immunology↗