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Ma, X.

Publications and source records attributed to Ma, X..

At least 73 records · Page 4Linked to original sources

A Long-Context Generative Foundation Model Deciphers RNA Design Principles

Programmable design of RNA sequences with defined functions remains a central challenge in biology. Despite recent advances, existing RNA generative models lack robust controllable design capabilities and are constrained by short context windows, limiting their capacity to model the complex evolutionary manifold of full-length transcripts. Here, we introduce EVA (Evolutionary Versatile Architect), a long-context generative RNA foundation model trained on over 114 million full-length RNA sequences spanning the full breadth of evolutionary diversity. By integrating a Mixture-of-Experts architecture with an 8,192-token context window, EVA learns a unified, evolution-consistent representation of RNA sequence space that captures both global transcript structure and fine-grained functional elements. EVA establishes a unified framework for a broad spectrum of RNA design tasks within a single architecture, ranging from mutational fitness prediction to context-aware sequence engineering. We demonstrate EVAs versatility through the de novo design and targeted optimization of diverse RNA classes, including tRNAs, aptamers, and CRISPR guide RNAs, as well as mRNA and circular RNA therapeutics. In systematic evaluations, EVA achieves state-of-the-art performance across seven of nine established benchmarks, improving structural modeling accuracy by up to an order of magnitude compared to existing approaches. EVA is fully open-source at the following repository: https://github.com/GENTEL-lab/EVA.

molecular biology↗

STEVE: Single-cell Transcriptomics Expression Visualization and Evaluation

Single-cell RNA sequencing (scRNA-seq) has become a key technology for characterizing cell-type heterogeneity in complex tissues. However, its utility depends on accurate and reproducible cell-type annotation, which remains a major analytical challenge. Although hundreds of computational tools have been developed for automated annotation, there is currently no systematic framework to evaluate annotation robustness in a dataset-specific manner or within the context of complete analytical pipelines. Here, we present STEVE (Single-cell Transcriptomics Expression Visualization and Evaluation), a quantitative framework designed to assess the accuracy, robustness, and reproducibility of cell-type annotation in scRNA-seq studies. STEVE implements three complementary in silico evaluation modules: (i) Subsampling Evaluation to quantify annotation stability under varying reference sizes and data partitions; (ii) Novel Cell Evaluation to assess the ability to detect previously unseen cell types; and (iii) Annotation Benchmarking to compare alternative annotation tools against ground-truth labels. In addition, STEVE includes a Reference Transfer Annotation module that enables cross-dataset cell-type mapping using external reference datasets. All modules are built upon a unified probabilistic framework that provides consistent confidence estimation across evaluation scenarios. We evaluated STEVE across four independent scRNA-seq datasets with experimentally defined or expert-curated cell-type labels. Our results show that annotation robustness is strongly influenced by the annotation method, biological separability, dataset complexity, and batch effects. STEVE provides a practical framework for quantifying annotation uncertainty and improving reproducibility in single-cell transcriptomic analyses. STEVE is freely available at GitHub (https://github.com/XiaoDongLab/STEVE).

bioinformatics↗

Multi-component functionalized Bifidobacterium longum hydrogel for multi-target integrated therapy of colitis-associated anxiety and depression

Inflammatory bowel diseases (IBDs) are frequently accompanied by anxiety and depression, largely driven by perturbed gut-brain axis signaling. However, current oral therapies remain constrained by the spatial and functional separation between intestinal inflammation and central nervous system dysfunction. Here, we present a comprehensive gut-brain dual region integrated therapeutic strategy based on functionalized Bifidobacterium longum hydrogel (INPs@BL@Gel), in which baicalin and tyrosine are coordinated with Fe(III) to form infinite coordination polymers (ICPs), coated with inulin, assembled onto Bifidobacterium longum (BL), and subsequently encapsulated within a pH- and matrix metalloproteinase-responsive silk fibroin-gelatin hydrogel. INPs@BL@Gel exhibits high drug-loading, effective gastric protection, inflammation-triggered release, and long-term intestinal colonization. Within the inflamed intestine, BL and components synergistically suppress inflammatory responses, restore gut microbiota homeostasis, and promote intestinal barrier repair through multi-target integrated therapy. Importantly, BL combined with components markedly enhances the production of beneficial neuroactive metabolites such as homovanillic acid and short-chain fatty acids, which integrated regulate neuroinflammation, preserve synaptic function, and facilitate blood-brain barrier repair via the gut-brain axis. In vivo studies demonstrate that INPs@BL@Gel not only exert potent therapeutic efficacy against colitis and effectively alleviate associated depression, but also reshape the gut microbiota and restore barrier integrity, achieving an remarkable comprehensive therapeutic effect. O_FIG O_LINKSMALLFIG WIDTH=158 HEIGHT=200 SRC="FIGDIR/small/710940v1_fig1a.gif" ALT="Figure 11"> View larger version (59K): org.highwire.dtl.DTLVardef@1a831f3org.highwire.dtl.DTLVardef@1676617org.highwire.dtl.DTLVardef@15f99c1org.highwire.dtl.DTLVardef@1677cc4_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOScheme 1.C_FLOATNO (a) Schematic diagram of the design and preparation of functionalized Bifidobacterium longum hydrogel. (b) Exploration of the mechanism of INPs@BL@Gel in treating colitis-associated anxiety and depression through a dual-site multi-target synergistic strategy. C_FIG

pathology↗

Chemical Proteomic Profiling of the Histaminylation Proteome in Cancer Cells Unveils Uncharted Epigenetic Marks on Core Histones

Histamine is a key signaling molecule in pathophysiology that can exhibit significant regulatory roles in diverse health and disease status. Besides the well-studied noncovalent interactions between histamine and its receptors, protein histaminylation is a recently discovered mechanism of action, through which histamine regulates cellular signaling pathways in a covalent modification manner. Histaminylation is an emerging protein post-translational modification, where an isopeptide bond is formed between the histamine primary amine and {gamma}-carboxyl group of glutamine through a transamidation reaction catalyzed by transglutaminase 2 (TGM2). However, due to the lack of efficient pan-specific antibodies targeting histaminylated glutamine, the histaminylation proteome in cells remains poorly explored. Here, we report the design and development of a novel N{tau}-propargylated histamine (N{tau}-PH) probe as well as its successful application in chemical proteomic profiling of the histaminylation proteome in cancer cells. Notably, new TGM2-catalyzed epigenetic marks on core histones, e.g., H2AX-Q84 and Q104 histaminylation, have been identified from cancer cells and verified. Lastly, the crosstalk between H2AX histaminylation and {gamma}H2AX formation was discovered in this study, suggesting that TGM2-mediated histaminylation plays a critical role in DNA damage responses.

biochemistry↗

Consistent EMG encoding during reach and grasp by neurons in motor cortex

Identifying what the activity of neurons in the primary motor cortex (M1) represents is essential for understanding motor computation. Yet the relation of M1 to muscles and movement remains unresolved, in part because the kinematic variables M1 appears to encode differ across the limb: hand velocity during reaching, but joint position during grasping. This discrepancy has been taken to imply fundamentally distinct control strategies for proximal and distal segments. Yet, here we show that a single, muscle-based control principle accounts well for both observations. We recorded neural activity, electromyographic (EMG) signals, and movement kinematics from macaque monkeys performing planar reaching, wrist movement, or free-form grasping tasks. Across behaviors, EMG-based encoding models explained M1 firing rates as accurately as the best-performing kinematic model: velocity for reaching, position for grasping, and either variable for wrist movements. Impulse response analysis revealed that these task-dependent kinematic relationships arise from the differences in mechanical impedance of each limb segment: the inertial and intersegmental coupling which dominate the dynamics of the proximal arm are far less important in the hand. These findings indicate that M1 output has a relatively simple, consistent relation to muscle activation and that the apparent divergence in kinematic encoding is a consequence of limb mechanics rather than distinct cortical strategies.

neuroscience↗

Tabular foundation model predicts alternative lengthening of telomeres (ALT) and identifies SMARCAL1 as a target in ALT-driven cancers

Alternative lengthening of telomeres (ALT) is a telomerase-independent pathway used by aggressive cancers to maintain their replicative immortality. Because ALT is absent from normal human cells, it is an appealing target for cancer therapy, but the lack of ability to determine ALT status at scale has hindered discovery. Here, we developed ALTitude, a machine learning method from a tabular foundation model that infers ALT from cell line whole genome sequencing data, without need for paired germline analysis. We deployed ALTitude across the DepMap, doubling the number of known ALT+ cancer models. Systematic integration of ALTitude with CRISPR-Cas9 screens yielded the selective dependency on SMARCAL1 in ALT+ cell lines, where we show it stabilizes the ALT phenotype. Acute depletion of SMARCAL1 leads to G2/M arrest, mitotic catastrophe, and cell death. These data provide a valuable resource for studying ALT-related genomic features and present SMARCAL1 as a therapeutic target for ALT+ malignancies.

cancer biology↗

How Not to be Seen: Predicting Unseen Enzyme Functions using Contrastive Learning

MotivationPredicting enzyme function from its sequence is still an unsolved problem in the life sciences. Moreover, with the explosion of annotated genome data, we are inundated with potential enzymatic sequences that have not yet been biochemically characterized. While it is not possible to assign a not-yet-existing label to such a sequence, there is high value in placing the sequence as accurately as possible in known function space. Doing so can help provide more accurate falsifiable hypotheses for experimentalists wishing to characterize enzymes from specific functional families. ResultsHere we present a contrastive learning algorithm for predicting enzyme function from sequence. Our method, EnzPlacer, predicts the third, second, and first EC numbers for a protein whose fourth EC number is not in the training corpus. This novel prediction mechanism accurately places a protein sequence within a narrowed-down functional context, even if the precise function remains unknown. AvailabilityEnzPlacer is available from https://github.com/drxiangma/EnzPlacer under a GPL3 license. Contactqli@iastate.edu

bioinformatics↗

Erythropoietin Mediates Glycerophospholipid Remodeling During Human Early Erythropoiesis

The unique biconcave morphology and deformability of mature red blood cells (RBCs) require a specific membrane lipid composition. Disruption of this special lipid profile is seen in multiple types of anemia and bone marrow (BM) failure diseases, yet molecular mechanisms regulating lipid metabolism during normal erythroid differentiation remain poorly defined. Here, we identify a previously undescribed role for erythropoietin (Epo) in contributing to the appropriate lipid composition of differentiating human erythroid cells. Using single-cell transcriptomic profiling of ex vivo cultures of human BM-derived hematopoietic stem and progenitor cells cultured with or without Epo, we delineated transcriptional dynamics across differentiation stages, identifying the Epo-dependent transition of burst-forming unit erythroid (BFU-E) to colony-forming unit erythroid (CFU-E) progenitors. Comparative analysis revealed the activation of canonical erythroid programs involving heme biosynthesis, globin expression, and iron regulation, and additionally, uncovered a transient upregulation of lipid metabolic pathways during the BFU-E to CFU-E transition. Complementary untargeted lipidomics demonstrated Epo-dependent alterations in specific glycerophospholipid (GPL) species, consistent with differential expression of GPL biosynthesis genes in the single cell dataset. Intracellular flow cytometry further confirmed the requirement of Epo for maintaining enzymes critical for phosphatidylcholine and phosphatidylethanolamine synthesis in erythroid cells. Together, these multiomic findings reveal a new role for Epo in modulating lipid metabolism during early erythropoiesis and provide mechanistic insight into how membrane lipid composition is dynamically regulated to support normal red cell development.

cell biology↗

Detection of Somatic Point Mutations Directly from Spatial Transcriptomics Enables in vivo Spatiotemporal Lineage Tracing

Spatial transcriptomics reveals tissue organization but lacks in vivo lineage-tracing methods applicable to humans. We introduce SpaceTracer, a computational framework that accurately detects somatic single-nucleotide variants (SNVs) directly from spatial transcriptomics data. By leveraging naturally occurring somatic SNVs, SpaceTracer reconstructs cellular phylogenies within native tissue architecture, enabling the mapping of lineage spread, migration, lineage-coupled expression changes and lineage-aware local interactions. Applied to human cutaneous squamous cell carcinoma, it traced tumor initiation and progressions, uncovered widespread pre-invasive migration of dedifferentiated epithelial cells and characterized mutant B cells migrating from tertiary lymphoid structures (TLS) into the tumor boundary. The framework also reconstructed developmental lineages across multiple tissues and identified tissue-resident mutant immune cells. SpaceTracer thus provides a perturbation-free platform for high-resolution spatiotemporal lineage tracing, offering a transformative tool for elucidating complex biological systems--especially tumor-immune ecosystems--with direct implications for advancing cancer immunotherapy.

bioinformatics↗

Unravelling genome-wide mosaic microsatellite mutations at single-cell resolution

Short tandem repeats (STRs), or microsatellites, are highly mutable genomic elements that modulate gene regulations and are implicated in a range of human diseases. However, detecting mosaic STR mutations at single-cell resolution remains challenging due to both technical and biological complexities. To address this, we developed BayesMonSTR, a robust algorithm that enables accurate detection of mosaic STR mutations. Using this tool in single-cell analysis of human tissues, we reveal an accumulation of longer mosaic STR insertions and deletions (indels) in aging mitotic and post-mitotic cells. Strikingly, prefrontal cortex (PFC) neurons accumulate a higher burden of STR mutations than B cells or lung epithelium, with aged neurons exhibiting a particularly pronounced increase in longer STR deletions. These mutations are enriched at transcription start sites (TSSs) and active enhancers of highly expressed genes. Our work establishes a foundation for genome-wide, hypothesis-free discovery of disease-associated mosaic STR mutations and reveals a previously unexplored landscape of mosaic STR variation in development and aging.

bioinformatics↗

Novel Bacillus altitudinis endolysin (ArtE2) targeting both Gram-positive and Gram-negative bacteria

Antibiotic resistance is a major global health concern. The development of new antibiotics and therapeutics is crucial for the future. Bacteriophages produce endolysins that induce bacterial lysis, making them a promising treatment option. Deep sequencing was used to identify and isolate genes encoding endolysins from Bacillus spp.. We characterized the biological activities of these endolysins. Additionally, this study focused on the design of a new chimeric endolysin, ArtE2, which combines endolysin-2 with a polycationic peptide to address the bacterial activity in gram-negative pathogenic bacteria. Using bioinformatic tools, we conducted three-dimensional modeling of the endolysin ArtE2 and its interactions with peptidoglycan fragments. In this study, we tested the activity of chimeric endolysins against both Gram-positive and Gram-negative bacteria. All endolysins share the same catalytic domain and diverse cell-binding domains. Some endolysins are highly specific to certain bacterial species or strains, whereas others have broader specificities. Histidine interactions are an important part of the mechanism by which ArtE2 connects with bacterial peptidoglycan. Additionally, the engineered endolysin ArtE2 was highly effective at killing Staphylococcus aureus and Escherichia coli. In silico analysis showed that the fusion did not negatively affect endolysin folding or activity. These findings suggest that ArtE2 could be used to develop efficient antibacterial controls targeting pathogenic Gram-positive and Gram-negative bacteria.

microbiology↗

NIPBL-mediated 3D genome folding translates enhancer priming into gene activation and safeguards lineage fidelity during embryonic transitions

Precise gene control by complex regulatory landscapes is fundamental to embryo development, yet the instructive role of 3D genome architecture remains controversial. While acute cohesin depletion completely disrupts genome folding, it yields modest transcriptional impacts, but these findings are often confounded by cohesins essential roles in cell division and proliferation. Here, we resolve this discrepancy by decoupling architectural functions from cell-cycle roles using an acute NIPBL degron system. By integrating single-gene imaging with single-cell and bulk multi-omics during mouse pluripotency transitions and germ-layer specification, we show that NIPBL-mediated cohesin function is required for proper de novo activation of lineage-specifying genes. Mechanistically, NIPBL translates epigenetic priming into transcriptional outputs by physically bringing distal enhancers and target promoters into proximity. We further uncover a dual regulatory role: an acute requirement for establishing new enhancer-promoter interactions during cell state transitions and a long-term role in safeguarding transcriptional fidelity by preventing ectopic gene de-repression. Our findings demonstrate that NIPBL/cohesin-orchestrated genome folding facilitates the faithful execution of developmental gene expression programs. HighlightsO_LIAcute NIPBL depletion decouples the architectural functions of cohesin from its essential roles in chromosome segregation and cell cycle progression. C_LIO_LINIPBL-mediated loop extrusion is required to translate the epigenetic priming of distal enhancers into de novo gene activation during embryonic state transitions. C_LIO_LINIPBL is a "rate-limiting physical relay" required to bring distal enhancers and target promoters into proximity to initiate transcription. C_LIO_LI3D genome architecture serves a dual role: enabling acute enhancer-promoter communication and safeguarding long-term lineage fidelity by preventing ectopic gene de-repression. C_LI

genetics↗

The CCCH Zinc Finger Gene PgCCCH50 from Pearl Millet Confers Drought and Salt Tolerance through an ABA-Dependent PgAREB1-PgCCCH50 Module

Abiotic stresses like drought and salinity severely constrain crop productivity. Pearl millet (Pennisetum glaucum L.), a stress-resilient cereal of global importance, is ideal for deciphering genetic adaptation. Although CCCH zinc finger proteins play key roles in plant stress responses, members with multiple regulatory functions remain unknown in this crop. This study analyzed 53 CCCH genes in pearl millet, examining their phylogeny, structure, chromosomal localization, and promoter cis-elements. Expression profiling revealed seven CCCH genes responsive to multiple stresses. Functional characterization of PgC3H50 showed that its overexpression in Arabidopsis conferred enhanced tolerance to drought and salt, evidenced by improved physiological parameters and upregulation of stress-responsive genes. We discovered that the ABA-responsive transcription factor PgAREB1(ABSCISIC ACID RESPONSIVE ELEMENT BINDING PROTEIN 1) directly binds to ABRE cis-elements in the PgC3H50 promoter and activates its transcription, validated by yeast one-hybrid, dual-luciferase, and EMSA assays. This defines a novel PgAREB1-PgC3H50 regulatory module within the ABA-mediated stress signaling pathway. Our findings provide a valuable genetic resource for the pearl millet CCCH family and unveil a promising candidate gene and transcriptional regulatory module for engineering crops with improved tolerance to drought and salinity. HighlightThis study reports the first genome-wide analysis of the CCCH family in pearl millet and identifies the novel PgAREB1-PgCCCH50 module as essential for salt and drought tolerance.

plant biology↗

Functional modules predict cancer-relevant genetic interactions in mammalian cells

Genetic interactions can reveal gene function and identify disease-relevant synthetic lethals, but resource-intensive screening in human cells constrains experimental scope and limits our understanding of how generalizable sparse hits are. Here, we leverage principles from yeast genetic networks to identify human gene modules involved in receptor tyrosine kinase signaling and DNA damage response that are predicted to be enriched for genetic interactions, then use our enCas12a-based In4mer combinatorial knockout platform to efficiently screen these modules across diverse cancer cell lines. We identify hundreds of unreported synthetic lethals, including a dense network within the protein N-linked glycosylation machinery that shows both evolutionary conservation and network rewiring, and we confirm that interactions discovered in 2D cell culture are maintained in more physiologically relevant models. Critically, a meta-analysis within and between screens highlights sources of variation in published results, reveals the potential for false positives in screens with many essential genes, and demonstrates the need to move beyond DDR for actionable synthetic lethalities.

systems biology↗

Humanized Extracellular Vesicles for Efficient RNA Delivery

Engineered extracellular vesicles (EVs) are a class of non-viral delivery vectors for RNA-based vaccines and gene therapies. A specialized form of engineered EVs, known as enveloped protein nanocages (EPNs), has been developed to enhance cargo loading and delivery. When EPNs are equipped with a viral fusogen, such as vesicular stomatitis virus glycoprotein (VSV-G), they have been shown to deliver proteins or RNA efficiently into recipient cells. Comparisons across different EPN types and optimization of their different features have been difficult, as assays for their activity have not been reported for single, active units. As we were interested in optimizing EVs, we first developed a biological titration assay inspired by the methods used for infectious viral particles. With this assay, we optimized EVs using a modular platform, creating EVs composed predominantly of human-derived protein components. This system achieved efficient RNA delivery, with functional titers comparable to those of lentiviral vectors. The optimized chimeric proteins comprising the EV particles integrate domains from human epsin 1, human citramalyl-CoA lyase beta-like protein (CLYBL), and human CEP55. The constructs also include a short 21-amino-acid peptide from a non-human source for RNA packaging, resulting in an EV-based RNA delivery system with reduced immunogenicity compared with EPNs and retroviral virus-like particles (VLPs). Significance StatementWe developed engineered extracellular vesicles (EVs) as RNA delivery vehicles to address limitations of virus-like particles (VLPs) and lipid nanoparticles (LNPs) in gene therapies and vaccines. We first developed an assay for individual active particles, using methods typically employed for viral titrations. This approach allowed iterative optimization of a modular EV platform. Our optimized particles comprise primarily human proteins and reach titers that comparable to those of lentiviral vectors.

bioengineering↗

On the stabilization of plant lipid droplets: Dynamic interplay between oleosins and phospholipids

As the central organelles of lipid and energy homeostasis in plant seeds, lipid droplets (LDs) consist of a neutral lipid core, decorated by phospholipids (prominently phosphatidylcholines, PCs) and surfactant-like proteins (mostly oleosins, OLs). So far, the dynamic interplay between PCs and OLs at the LD interface remains unclear. The presented work addresses this knowledge gap by reconstituting oil-in-water emulsions stabilized by OLs and PCs using microfluidic systems. Our results show that the resistance to droplet coalescence is primarily provided by OLs. We further reveal that the addition of PCs alters the assembly of OLs at the interface, reducing the OL network density and interfacial elasticity, thereby rendering a weaker interface. In conclusion, our study suggests complementary roles, with OLs acting as the primary stabilizers while PCs playing a destabilizing role. This contrast likely contributes to the observed metastability of LDs and can be exploited to design stimuli-responsive emulsions. HIGHLIGHTSO_LIOleosins form an interfacial network that stabilizes the oil-water interface. C_LIO_LIPhosphatidylcholines globally weaken the oleosin network and promote droplet coalescence. C_LIO_LIMicrofluidics enables controlled reconstitution and real-time analysis of lipid droplets. C_LIO_LIOleosin-phospholipid interplay explains lipid droplet metastability and can guide the design of bio-inspired emulsions. C_LI

biophysics↗

A haplotype-resolved T2T genome assembly of Indigofera pseudotinctoria reveals the genetic basis of flavonoid biosynthesis in Chinese Indigo

Indigofera pseudotinctoria, commonly known as Chinese Indigo, is a multifunctional leguminous shrub widely distributed in East Asia, valued for its medicinal, ecological, and forage importance, and naturally adapted to drought and nutrient-poor soils. However, the absence of genomic resources has hindered insights into the genetic basis of its bioactive metabolites and adaptive traits. Here, we present a haplotype-resolved, telomere-to-telomere (T2T) reference genome of I. pseudotinctoria, which represents the first complete genome within the genus Indigofera. By integrating PacBio HiFi sequencing, Oxford Nanopore ultra-long reads, and Hi-C chromatin conformation sequencing technologies, we successfully constructed two gap-free haplotypes assemblies (647.38 Mb and 657.52 Mb), characterized by high BUSCO completeness and QV scores, and fully captured all telomeric sequences. Comparative analysis between haplotypes revealed extensive synteny but notable structural heterozygosity but notable structural heterozygosity. Approximately 46% of structural variations overlap with genic or regulatory regions, leading to allele-specific expression divergence. Between the two haplotypes, we identified 2,607 and 2,331 haplotype-specific genes, reflecting a complementary functional specialization in defense and repair versus metabolism and growth. Integrative transcriptomic and metabolomic profiling across six tissues reconstructed the flavonoid biosynthetic network and identified MYB, bHLH, NAC, WRKY, and ERF transcription factors regulating five key pharmacologically active flavonoids (Calycosin, Butein, Sulfuretin, Chrysoeriol, and Genistin). These results collectively uncover the haplotype-specific regulatory and structural basis of Indigofera pseudotinctoria and establish a high-quality genomic framework for evolutionary, medicinal, and metabolic engineering studies in leguminous plants, and provide a framework for molecular breeding and bioactive compound discovery in medicinal legumes.

genomics↗

ERAD Activity Distinguishes the Functional Heterogeneity of Hematopoietic Stem Cells

Hematopoietic stem cells (HSCs) rely on precisely controlled proteostasis to sustain lifelong self-renewal, yet whether intrinsic proteostatic characteristics can prospectively define functional diversity within the HSC pool remains unknown. In this study, we developed a dual-fluorescence reporter system to visualize endoplasmic reticulum-associated degradation (ERAD) activity in vivo and discovered that ERAD activity can prospectively predicts the long-term reconstitution potential of HSCs. Remarkably, ERAD states were maintained through self-renewal, revealing an inheritable "proteostatic memory" within the HSC pool. Transcriptomic and functional analyses identified SOCS2 as a key regulator of this process: SOCS2 inhibits JAK2 signaling to sustain ERAD activity, whereas hyperactive JAK2 interacts with the ERAD E3 ligase Hrd1 and suppresses VCP-mediated misfolded substrate. These findings define a SOCS2-JAK2-ERAD axis that connects cytokine signaling to intrinsic proteostasis remodeling, establishing ERAD activity as a predictive and heritable marker of HSC function and providing a conceptual framework for understanding hematopoietic stem cell heterogeneity.

cell biology↗