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Wang, J.

Publications and source records attributed to Wang, J..

At least 775 records · Page 43Linked to original sources

Tibicos differentially affects faecal microbiota composition and short-chain fatty acid production in prediabetic and healthy adults in a simulated digestive tract

Prediabetes and obesity are increasingly prevalent chronic pro-inflammatory conditions driven by gut microbiota dysfunction. To assist in the management of such diseases, researchers are interested in gut-microbiota targeted dietary interventions. Tibicos is a plant-based fermented beverage shown to modulate gut microbiota, with anti-hyperglycaemic and anti-inflammatory effects in in vitro and in vivo human and animal studies. We investigated the effects of ginger-cayenne tibicos on healthy and prediabetic pooled faecal microbiota, with a static in vitro digestion/ colonic fermentation model using faeces from adult overweight/ obese donors with prediabetes, and healthy donors (n=3 per group). Changes in faecal microbiota composition and short-chain fatty acid (SCFA) production were determined. Baseline prediabetic faeces was less abundant in butyrate-producing bacterial taxa and SCFAs. In vitro colonic fermentation Time and Status (prediabetic vs. healthy) were the major determinants of shifts in faecal microbial community abundance and diversity. Tibicos reduced beneficial bacterial taxa loss in prediabetic faecal microbiota. However, tibicos improved the functional capacity of healthy faecal microbiota to a larger extent, with increased SCFA production and significant correlations between bacterial species and SCFAs. The differential shifts in composition and SCFAs observed during simulated gastrointestinal transit suggest that ginger-cayenne tibicos has the potential to beneficially modulate human faecal microbiota in both healthy and prediabetic participants. This study indicates that ginger-cayenne tibicos may be a useful tool in the management of prediabetes and obesity in humans and provides pilot data for the development of larger clinical trials.

microbiology↗

Evolutionary responses and genomic consequences of polyploidization in natural populations of Orychophragmus

Polyploidization has occurred throughout the tree of life and is particularly common in plants. Despite its ubiquity, our understanding of the short- and long-term effects and consequences of genome doubling in natural populations remains incomplete. In this study, we identified a novel ploidy-variable species system within the ornamental and industrial oilseed genus Orychophragmus (Brassicaceae), which comprises six species, including diploid and tetraploid cytotypes of O. taibaiensis. By integrating population-scale genomic and transcriptomic datasets across the species in this genus, we constructed a robust phylogenetic framework and investigated the divergence and demographic history of O. taibaiensis in comparison to its relatives. Specifically, we characterized the geographical distribution patterns of diploids and tetraploids in natural populations of O. taibaiensis, confirmed the autopolyploid origin of tetraploids, and inferred their origin time relative to diploid counterparts. Our findings further revealed that, following genome doubling, tetraploids accumulated a higher genetic load of deleterious mutations, likely due to relaxed purifying selection facilitated by allelic redundancy. Additionally, genome doubling was associated with pronounced changes in gene expression patterns, with differentially expressed genes evolving under relaxed selective constraints. These results highlight that the initial masking of deleterious mutations, changes in expression regulation, and divergent efficacy of selection likely all contribute to shaping the establishment and evolutionary potential of polyploids.

molecular biology↗

A humanized 16A antibody conjugated with DNA topoisomerase I inhibitors, targeting a GSTA glycosite-signature epitope.

BackgroundWe previously reported the 16A antibody, which binds to the abnormally glycosylated tandem repeat region of the MUC1 glycoprotein, and developed 16A-MMAE as an antibody-drug conjugate. However, its antitumor efficacy as an antibody-drug conjugate with DNA topoisomerase Iinhibitors remains unknown. MethodsWe humanized the 16A antibody and conjugated it to DXd and MF6, two DNA topoisomerase I inhibitors. The antitumor efficacy of the conjugates was evaluated in vitro and in vivo. ResultsThe humanized 16A-DXd conjugate showed potent antitumoral efficacy, with an IC50 in the nM range against CFPAC1 cells. In vivo, h16A-DXd and h16A-MF6 inhibited tumor growth in asubcutaneous mouse tumor transplantation model using CT26-COSMC KO-hMUC1 cells, administered at a dose of 10 mg/kg. ConclusionsThe high antitumor efficacy of h16A-conjugated DNA topoisomerase I inhibitors supports further clinical development. The relatively low toxicity of h16A-DXd and h16A-MF6 may enable a higher therapeutic window, since MUC1-positive cells internalize the antibody-drug conjugate more efficiently.

pharmacology and toxicology↗

Soluble Immune Factor Profiles in Blood and CSF Associated with LRRK2 Mutations and Parkinson's Disease

Background and ObjectivesMutations in the Leucine-rich repeat kinase 2 (LRRK2) gene are one of the most common genetic causes of Parkinsons disease (PD) and are linked to immune dysregulation in both the central nervous system and periphery. However, peripheral and central profiles of soluble immune factors associated with LRRK2 mutations and PD have not been comprehensively characterized. Using serum and CSF samples from the LRRK2 Cohort Consortium (LCC), this study aimed to probe a broad range of soluble immune biomarkers associated with LRRK2 mutations and PD. MethodsWe investigated the levels of soluble immune regulators in the serum (n=651) and cerebrospinal fluid (CSF, n=129) of LRRK2 mutation carriers and non-carriers, both with and without PD. A total of 65 cytokines, chemokines, growth factors, and soluble receptors were assessed by Luminex immunoassay. A multivariable robust linear model was used to determine levels associated with LRRK2 mutations and PD status, adjusting for age, sex, and sample cohort. Correlations were assessed using the Spearman correlation coefficient. LRRK2 G2019S knock-in mice were used to validate the associations identified in the LCC. ResultsIn this extensive discovery cohort, we identified several elevated serum immune regulatory factors associated with LRRK2 mutations. In particular, serum stromal cell-derived factor-1 alpha (SDF-1 alpha) levels, as supported by findings in LRRK2 G2019S knock-in mice, and tumor necrosis factor receptor II (TNF-RII) were significantly increased after multiple comparison adjustment. In contrast, LRRK2 mutations were associated with reduced soluble immune markers, including BAFF, CD40-Ligand, I-TAC, MIP-3 alpha, NGF beta, and IL-27 in CSF. Those with clinically diagnosed PD, with or without LRRK2 mutations, did not show strong signals in serum but reduced inflammatory analytes in CSF, including MIF, MMP-1, CD30, Tweak, and SDF-1 alpha. In addition, we found that the serum levels of these soluble immune factors display varied correlations with their corresponding CSF levels. DiscussionThis study highlights distinct immune profiles associated with LRRK2 mutations and PD in the periphery and CNS. Serum levels of SDF-1alpha and TNF-RII were elevated in LRRK2 mutation carriers, while CSF immune markers were reduced. In PD, irrespective of LRRK2 status, reduced CSF inflammatory analytes and weak serum signals were observed. These results provide insight into immune dysregulation linked to LRRK2 mutations. If replicable in independent datasets, they offer potential avenues for biomarker and therapeutic exploration.

neuroscience↗

A Comprehensive Reference Catalog of Human Skin DNA Virome Reveals Novel Viral Diversity and Microenvironmental Influences

IntroductionHuman skin serves as a dynamic habitat for a diverse microbiome, including a complex array of viruses whose diversity and roles are not fully understood. ObjectivesThis study aims to enhance our understanding of this skin viral diversity through the construction of a detailed, non-redundant DNA viral reference catalog. MethodsA total of 2,760 skin metagenomes from six published skin studies were collected. A skin virome catalog was constructed using methods independent of reference databases. Viral characteristics were identified through cross-cohort meta-analysis and used to characterize viral features across different skin environments. ResultsWe identified 20,927 viral sequences, which clustered into 2,873 viral operational taxonomic units (vOTUs). Among these, 2,610 represent previously unrecorded viral sequences, uncovering a substantial breadth of viral diversity on human skin. The results also highlight significant differences in viral communities that are associated with varying skin microenvironments. The oily skin is enriched in Papillomaviridae; the dry skin area is enriched in Autographiviridae, Inoviridae and Mitoviridae; and the moist skin is enriched in Herelleviridae, indicating the adaptive nature of viruses. We also investigated the relationship between bacteriophages and bacteria on the skin surface. We found that skin bacteria such as Pseudomonas, Klebsiella, and Staphylococcus are infected by phages from the class Caudoviricetes. ConclusionThis comprehensive skin DNA viral catalog significantly advances our understanding of the viromes role within the skin ecosystem. The findings highlight the adaptive nature of viruses to different skin microenvironments and their interactions with resident bacteria. This catalog serves as a valuable resource for further epidemiological and therapeutic research, potentially leading to better management and treatment of skin conditions influenced by the skins virome.

microbiology↗

Hydrogen-Induced Calcium Influx via the TRPC4-TRPC4AP Axis

BackgroundCalcium ions (Ca{superscript 2}) serve as universal intracellular messengers regulating diverse physiological processes, while dysregulated Ca{superscript 2} homeostasis triggers cytotoxicity. Molecular hydrogen (H2) exhibits protective effects against oxidative stress-related pathologies, but its mechanism of action remains incompletely understood. Transient receptor potential canonical 4 (TRPC4) channels and their associated protein TRPC4AP are critical mediators of Ca{superscript 2} influx ( [Ca{superscript 2}]i), yet their role in H2-mediated calcium signaling is unexplored. This study investigates the molecular mechanism by which H2 modulates Ca{superscript 2} dynamics through the TRPC4-TRPC4AP axis, aiming to establish its therapeutic potential for calcium-related disorders. MethodsThe study employed heterogeneous cellular models (e.g., mesenchymal stem cells, neurons, fibroblasts) and in vivo two-photon calcium imaging in C57BL/6J mice. Techniques included CRISPR-Cas9 knockout, siRNA-mediated gene silencing, molecular docking (AlphaFold 3), and protein-protein interaction analysis. Calcium flux was quantified via fluorescence imaging, while mitochondrial integrity and cytoskeletal dynamics were assessed using JC-1 staining, ATPase activity assays, and live-cell imaging. Structural validation of TRPC4-TRPC4AP binding sites utilized mutagenesis and complementation experiments. ResultsH2 selectively enhanced extracellular Ca{superscript 2} influx via TRPC4-TRPC4AP, with no cytotoxicity or mitochondrial dysfunction observed. Key arginine residues (730Arg-731Arg) in the TRPC4 CIRB domain formed hydrogen-bond networks essential for channel activation. In vivo, H2 increased neuronal Ca{superscript 2} transient frequency and amplitude in the primary motor cortex. TRPC4AP knockout abolished H2-induced Ca{superscript 2} influx, while mutagenesis of 730Arg/731Arg disrupted channel activity. H2 also promoted cytoskeletal remodeling and cell motility, dependent on TRPC4AP-mediated Ca{superscript 2} signaling. ConclusionsThis study identifies H2 as a novel calcium agonist that activates the TRPC4-TRPC4AP axis to regulate extracellular Ca{superscript 2} influx. The 730Arg-731Arg motif in TRPC4 serves as a critical H2-sensitive site, enabling dynamic calcium homeostasis without overload. These findings provide a mechanistic basis for H2-based therapies targeting calcium dysregulation in neurodegenerative, inflammatory, and metabolic diseases, while highlighting TRPC4AP as a pivotal molecular switch for gasotransmitter signaling.

biochemistry↗

Restoration of tumor suppressor protein with enhanced activity using engineered tRNAs to induce tumor regression

Cancer develops through a gradual accumulation of mutations including nonsense mutations in tumor suppressor genes (TSGs), which drive tumor proliferation and progression due to the impairment or complete loss of tumor suppressor protein function. The ability to restore functional tumor suppressor protein from mutant driver TSGs is a longstanding aspiration in cancer therapy, however, current strategies face formidable challenges in recovering proteins harboring heterogeneous mutations and circumventing dominant-negative effects exerted by endogenous mutant proteins. Therefore, the development of therapeutic interventions that are effective and generalizable across diverse nonsense mutations in cancer, to rescue endogenous mutant tumor suppressor proteins remains an urgent yet unmet need. Here we find that engineered suppressor transfer RNA (sup-tRNA) could overcome nonsense mutations in key driver tumor suppressor genes, such as TP53, thereby avoiding the dominant-negative effects through the restoration of endogenous mutant p53 with its original functions. Optimized sup-tRNA that we named super tRNA, enabling high-fidelity incorporation of desired amino acids, can further enhanced the transcriptional activity of p53 to suppress tumor cell proliferation. Moreover, we also establish a computational model to guide super tRNAs design, and demonstrate that super tRNA could effectively inhibit tumor growth by targeted readthrough of nonsense mutations in different tumor suppressor genes. In two xenograft models harboring nonsense mutant TP53, we observed up to a 70% reduction in tumor volume after lipid nanoparticle (LNP)-based sup-tRNA treatment, along with robust recovery of p53 expression and function, and no hematological or histological abnormalities detected. Our findings demonstrate the potential of sup-tRNA as a feasible and effective strategy to rescue and enhance tumor suppressor protein function, thereby preventing cancer development. As a novel therapeutic RNA, sup-tRNA provides a flexible strategy for targeting driver mutations in cancer, thereby expanding the potential of tRNA-based therapy in precision oncology.

bioengineering↗

Acquired resistance to sotorasib in mutant NSCLC is vulnerable to PI3K-mTOR pathway inhibition mediated by 4E-BP1 regulator of cap-dependent translation

Sotorasib and adagrasib have shown significant efficacy in KRASG12C mutant NSCLC; however, acquired resistance (AR) occurs within 6-12 months. While some resistance arises from new mutations, over half of the resistant cases lack identifiable genomic alterations. We hypothesize that resistance is driven by signaling network rewiring, creating new therapeutic vulnerabilities. To investigate AR mechanisms, multiple AR models, including cell lines, PDXs, CDXs, and PDXOs, were developed. H23AR and H358AR cells displayed >600-fold and 200-fold; and PDXO303AR and PDXO314AR organoids exhibited >300-fold and >100-fold resistance to sotorasib, respectively; however, no additional mutations in KRAS or other potential genetic alterations were identified. The AR cells and PDXOs also showed comparable resistance to adagrasib. Distinct protein signatures associated with KRAS reactivation, mTORC1 signaling upregulation, and PI3K/AKT/mTOR pathway activation were identified in TC303AR & TC314AR PDXs. PI3K protein levels were significantly elevated in AR PDXs, H23AR, and H358AR cells. Pharmacological inhibition of PI3K with copanlisib or genetic knockout via CRISPR-Cas9 restored sotorasib sensitivity, suppressed colony formation, and inhibited downstream effectors, including p-AKT, p-mTOR, p-S6, p70S6K, p-GSK3{beta}, and p-PRAS40 in AR cells. Copanlisib also sensitized both acquired and primary resistant PDXOs and synergized with sotorasib in restoring drug sensitivity. p4E-BP1 was significantly upregulated in H23AR and H358AR cells, which is suppressed by copanlisib. The level of p4E-BP1 expression was correlated with Sotorasib sensitivity in PI3K knockout clones, where the most sensitive clone displayed reduced or no p4E-BP1 expression. CRISPR-Cas9-mediated knockout of 4E-BP1, either alone or in combination with PI3K knockout, dramatically restored sotorasib sensitivity to levels comparable to parental cells. Suppression of 4E-BP1 hyperphosphorylation required dual inhibition of mTORC1 and mTORC2, and treatment with AZD8055 or sapanisertib (mTORC1/2 dual inhibitors) significantly dephosphorylated 4E-BP1 and restored sotorasib sensitivity in resistant cells and PDXOs. In PDX, CDX, and xenograft models in vivo, the combination of sotorasib with either copanlisib or sapanisertib resulted in robust, synergistic, and durable tumor regression at well-tolerated doses. These findings showed the critical role of PI3K/mTOR signaling as a bypass mechanism of resistance to KRASG12C inhibitors. We conclude that mTORC1/2 mediated inhibition of p4E-BP1 and combination strategies targeting this pathway effectively overcome acquired resistance to KRASG12C inhibitors in NSCLC.

cancer biology↗

Longitudinal analysis of retinal cell state transitions in RB1-deficient retinal organoids reveals the nascent cone precursors are the earliest cell-origin of human retinoblastoma

All cancers develop from malignant transformation of normal cells, while it is challenging to identify these "cells-of-origin" since it is impossible to witness the dynamic changes in human cancers. Retinoblastoma (Rb), an intraocular malignant cancer, is a typical model for study the molecular and cellular mechanisms of cancers. Although the maturing cone precursors (CPs) are proposed as the cellular origin of human Rb, it is unknow whether other retinal cells are also sensitive to RB1 inactivation. Here we developed RB1-deficient human retinal organoids (ROs) models from RB1-/- or RB1+/- human induced pluripotent stem cells (hiPSCs). RB1-/- hiPSCs developed into Rb tumors which recapitulated the features of human native Rb and had the ability to form consecutive orthotopic xenografts in mice. Importantly, RB1 loss induced the overproliferation of ATOH7+ neurogenic retinal progenitor cells (nRPCs), which disrupted the retinal development by generating proliferative, nascent retinal cells including retinal ganglion cells and CPs. scRNA-seq analysis verified the ATOH7+/RXR{gamma}+ nascent CPs survived and finally drove Rb development. In contrast, monoallelic RB1 inactivation with low pRB expression did not induce nascent CPs proliferation, but only induced nRPCs overproliferation which caused retinocytoma-like phenotype. Finally, a potential therapeutic agent for Rb was identified from multi-omics data. Our findings firstly indicate that nRPCs are the most sensitive cells to RB1 loss inducing nascent retinal cells abnormal proliferation, and ATOH7+ nascent CPs are the earliest cellular origin of human Rb, facilitating drug development for Rb.

cell biology↗

Leveraging mRNA platform for the development of vaccines against egg allergy

Food allergy has posed a major global health burden due to the rising prevalence and lack of effective prophylactic strategies. During the past decades, allergen-specific immunotherapy (AIT) has been used as a disease-modifying therapy for food allergic conditions, but due to the long-term treatment duration, poor patient compliance and unexpected adverse reactions, only a minority of patients benefit from AIT therapy. In this proof-of-concept study, using well-established mRNA platform, we developed mRNA vaccine candidates encoding for the major egg white allergen Gal d2 (also known as ovalbumin) and comprehensively evaluated the prophylactic efficacy against anaphylaxis in a Gal d2-induced allergic mouse model. Two vaccine formulations, Gal d2 mRNA vaccine and Gal d2-IL-10 mRNA vaccine, both demonstrated effective ability in preventing the onset of allergic disease, which is largely attributed to the versatilities of mRNA vaccine in eliciting allergen-blocking antibody, shifting Th2 towards Th1 immunity, as well as in generating peripheral tolerance.

immunology↗

Deep contrastive feature compression with classical machine learning enables ligand discovery through efficient triage of large chemical libraries

Improving in silico compound-protein interaction (CPI) predictability is critical for productive drug discovery. Current deep learning approaches largely rely on end-to-end models trained on limited labeled CPI datasets, overlooking the representational power of large-scale biochemical foundation models. We present COMRADE (Contrastive Multirepresentation Accelerated Docking Engine), a hybrid virtual screening framework that accelerates docking by triaging compounds using CE-Screen (Contrastive Embedding-Screen). CE-Screen leverages seven high-dimensional pretrained representations - including those from protein language models and molecular transformers, along with an original physics-based interaction potential encoding - for rapid first-pass screening [~]100x faster than docking. Its contrastive compression neural network maps these inputs onto a single compact, discriminative representation optimized for CPI prediction via a lightweight ensemble classifier. CE-Screen outperforms state-of-the-art end-to-end models by up to 111.11% on retrospective benchmarks and is successfully used to triage [~]10.8 million compounds against five targets, yielding novel hits for each one - including a new scaffold for the branched-chain ketoacid dehydrogenase kinase (BCKDK), an understudied yet high-value target in metabolic disease and oncology.

bioinformatics↗

CDKL5 modulates structural plasticity of excitatory synapses via liquid-liquid phase separation

Activity-dependent synaptic remodeling, essential for neural circuit plasticity, is orchestrated by central organizers within the postsynaptic density (PSD), including the scaffolding protein PSD95. However, the molecular mechanisms driving this process remain incompletely understood. Here, we identify CDKL5, a protein associated with a severe neurodevelopmental condition known as CDKL5 deficiency disorder (CDD), as a critical regulator of structural plasticity at excitatory synapses. We show that CDKL5 undergoes liquid-liquid phase separation (LLPS) in vitro and in cultured neurons, forming co-condensates with PSD95. This LLPS-driven process spatially organizes synaptic components, specifically enabling the synaptic recruitment of Kalirin7 to promote dendritic spine enlargement. Pathogenic mutations disrupt condensate formation by impairing the LLPS capacity of CDKL5, directly linking phase separation defects to the pathogenesis of CDD. Our findings reveal a crucial role for CDKL5 in synaptic plasticity and establish LLPS as a fundamental mechanism by which CDKL5 coordinates molecular events to reorganize PSD architecture during synaptic remodeling.

neuroscience↗

A novel immunogene therapy to cancer with high tumor selectivity and safety

Cancer immunotherapy has made significant advancements over the past few decades, with immune checkpoint and cytokine-based drugs being successfully implemented in clinical settings. Nonetheless, the effective and safe clinical application of these therapies is hindered by critical issues, such as severe toxicity to healthy tissues due to on-target off-tumor effects. In this study, we have developed a novel immunogene therapy characterized by high tumor selectivity and safety in vivo, effectively mitigating the off-tumor effects associated with current antibody-based immune checkpoint therapies. We engineered a gene expression vector that is specifically activated by NF-{kappa}B activity to co-express artificial microRNAs targeting two key immune checkpoints (PD-L1 and CD47) and cytokine IL-15. This vector is capable of selectively and effectively down regulating the expression of PDL1 and CD47 while over expressing IL-15 just exclusively in cancer cells, both in vitro and in vivo. Through this mechanism, both adaptive and innate immune responses can be simultaneously activated and enhanced via the transfection of this vector. The in vivo administration of this vector via recombinant adeno-associated virus (AAV) demonstrated significant antitumor activity, high tumor selectivity, and safety in murine models. Consequently, this vector may offer a potential more effective and safer alternative to the current immune checkpoint inhibitors in future clinical applications.

cancer biology↗

C9orf50 is a Targetable Spliceosome Regulator for Cancer Immunotherapy

Cancer cells harbor cell-intrinsic programs capable of sculpting immunogenic landscapes, yet molecular brakes that enforce immune evasion remain poorly defined. Here, we identify C9ORF50, a previously uncharacterized intrinsically disordered protein, as a liquid-liquid phase separation-driven regulator of RNA processing and actionable immunotherapy target. Genetic ablation of C9ORF50 induces selective intron retention in spliceosome component transcripts, leading to cytoplasmic accumulation of immunogenic double-stranded RNA (dsRNA). This dsRNA activates type I interferon pathway that in turn orchestrates a chemokine secretory program critical for T cell recruitment. The resultant enhancement of tumor immunogenicity and reprogramming of tumor immune microenvironment drives robust antitumor immunity, effectively converting immunologically "cold" tumors to "hot" phenotypes. Therapeutic targeting of C9ORF50 via RNA interference achieved robust tumor suppression in syngeneic models, suggesting its translational relevance. Notably, C9ORF50 exhibits tumor-predominant expression, with minimal baseline levels detected in healthy tissues or immune cell populations, underscoring its potential safety as a therapeutic target. Our study not only identifies C9ORF50 as a novel LLPS-dependent regulator of RNA splicing but also establishes it as a promising and potentially safe therapeutic target for cancer immunotherapy.

cancer biology↗

Comprehensive profiling of N6-methyladnosine (m6A) readouts reveals novel m6A readers that regulate human embryonic stem cell differentiation

N6-methyladenosine (m6A) methylation has emerged as a prevalent RNA modification that extensively impacts various physiological and pathological processes via various post-transcriptional readout effects in mammals. High-throughput methylome profiling has outlined the landscape of m6A modification sites, but their downstream readouts require comprehensive investigation. To this end, we systematically assessed the effects of m6A on mRNA half-life, translation efficiency, and alternative splicing across five cell lines (A549, HEK293T, HUVEC, JURKAT, and human embryonic stem cells (hESCs)) using actinomycin D-disrupted temporal transcriptome sequencing, ribosome sequencing, and ultra-high-depth transcriptome sequencing, respectively. Our analysis, coupled with the integration of public and re-profiled m6A methylome data, revealed high cell type specificity in m6A readouts where m6A level alone is insufficient to predict m6A readouts. Machine learning models focused on the RNA binding protein (RBP) binding context of m6A sites demonstrated substantial predictive ability of m6A readouts while prioritizing putative m6A readers from their informative RBP features. Four novel m6A readers (DDX6, FUBP3, FXR2, and L1TD1) were identified and validated through m6A RNA pull-down assays and transcriptome-wide RBP binding site mapping. Notably, FUBP3, FXR2 and L1TD1 were found to regulate hESC differentiation without impairing self-renewal, underscoring their critical roles in stem cell biology. Together, this study bridges the gap in understanding m6A functional readouts and lays the groundwork for future research on m6A-mediated stem cell fate decisions.

genomics↗

Chimeric Collagen-like Proteins with Tunable Structural Heterogeneity for Precise Control and Targeted Doxorubicin Delivery

Protein-based drug delivery systems offer advantages such as genetic tunability, structural homogeneity, and high biocompatibility. However, precisely controlling the assembly of protein nanoparticles and establishing correlations between their macroscopic properties and molecular architecture remain significant challenges. Here, inspired by chimeric collagen-like proteins, we rationally designed a series of de novo chimeric proteins comprising an N-terminal globular domain fused to a linear collagen-like domain. These structurally heterogeneous proteins were conjugated with doxorubicin (DOX) and homogenized to form chimeric collagen-like protein-DOX nanocomplexes (CDCNs). By fine-tuning the protein structure and domain organization, we achieved precise control over CDCN architecture and drug release kinetics. Furthermore, to enhance tumor specificity, triple-negative breast cancer (TNBC)- and glioblastoma (GBM)-targeting peptides were genetically fused to the chimeric proteins, respectively. In both in vitro and in vivo models of TNBC and GBM, CDCNs facilitated selective tumor accumulation, enhanced cellular uptake, and promoted apoptosis while minimizing off-target toxicity. This work establishes a strategy for designing protein-based nanoplatforms with programmable structures and tunable functionalities, offering promising potential for precisely controlling of protein-based delivery system.

bioengineering↗

Harnessing Uniform Design to Enhance AI-Driven Predictions of Physicochemical Properties of Short Peptides

Short peptides hold significant promise in drug discovery and materials science due to their biocompatibility, multifunctionality, and ease of synthesis. However, accurately predicting their physicochemical properties, a prerequisite for application development, remains a challenge. This study presents an innovative approach integrating uniform design (UD) with artificial intelligence (AI) to enhance prediction of key physicochemical properties, including aggregation propensity (AP), hydrophilicity (logP), and isoelectric point (pI). Using UD, we generate 31 distinct peptide datasets, with a consistent amino acid occupation fraction of 5% at each position, thereby creating unbiased training data for AI models. The performance of each AI model is rigorously evaluated using various testing schemes, and optimal sample sizes are determined for accurate prediction of each property. Additionally, Shapley Additive Explanations (SHAP) analysis identifies aromaticity, logP, net charge, and pI as the primary factors affecting peptide aggregation. This work provides comprehensive datasets on the physicochemical properties of all tetrapeptides, develops robust AI-based predictive models, and elucidates the relationships between key physicochemical characteristics and self-assembly behavior. By integrating experimental design, AI modeling, and peptide domain knowledge, our approach facilitates the discovery and optimization of functional peptides, offering new opportunities for peptide-based therapeutic applications.

bioinformatics↗

Stathmin 1 regulates mitophagy and cellular function in hematopoietic stem cells

Stathmin 1 is a cytoplasmic phosphoprotein that regulates microtubule dynamics via promotion of microtubule catastrophe and sequestration of free tubulin heterodimers. Stathmin 1 is highly expressed in hematopoietic stem cells (HSCs), and overexpressed in leukemic cells, however its role in HSCs is not known. Herein, we found that loss of Stathmin 1 is associated with altered microtubule architecture in HSCs, and markedly impaired HSC function. Transcriptomic studies suggested alterations in oxidative phosphorylation in Stmn1-/- HSCs, and further mechanistic studies revealed defective mitochondrial structure and function in the absence of Stathmin 1 with increased ROS production. Microtubules associate with mitochondria and lysosomes to facilitate autophagosome formation and mitophagy, and indeed we found that this critical mitochondrial quality control process is impaired in Stathmin 1-deficient HSCs. Finally, stimulation of autophagy improved the colony forming ability of Stmn1-/- hematopoietic stem and progenitor cells. Together, our data identify Stathmin 1 as a novel regulator of mitophagy and mitochondrial health in HSCs. Key PointsO_LIThe microtubule regulating protein Stathmin 1 is highly expressed in HSPCs and promotes normal microtubule architecture. C_LIO_LILoss of Stathmin 1 in HSPCs leads to impaired autophagy with abnormal mitochondrial morphology, decreased respiratory capacity, and impaired cellular function. C_LI

cell biology↗