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Yang, M.

Publications and source records attributed to Yang, M..

At least 73 records · Page 4Linked to original sources

Individual Brain Structure Deviations and its Gene Expression Signatures in Early-Onset Schizophrenia

BackgroundSchizophrenia is a highly heritable mental disorder associated with widespread anatomical alterations during neurodevelopment. Converging evidence suggests transcriptomic architecture underlying brain abnormalities in schizophrenia, while how individualized brain morphological deviations relate to gene expression levels remains unclear. MethodsTo investigate individual-level brain deviations and its transcriptomic signatures in schizophrenia, this study collected T1-weighted MRI data from 95 early-onset schizophrenia (EOS) patients and 99 typically developing (TD) controls. Normative modeling was used to measure individual deviations in cortical thickness and subcortical volume. Partial least squares regression was calculated to capture covarying patterns between structural deviations and whole-brain gene expression levels. Clustering analysis was performed on latent brain-gene covarying components, and the results were further functionally decoded through gene enrichment analyses. ResultsGroup-level comparisons suggested patients with EOS showed consistently decreased z-scores of cortical thickness in the frontal and temporal lobe regions, while increased inter-individual variability in the lingual gyrus. Clustering analysis of z-scores with transcriptomic signatures identified two distinct brain-gene covarying subtypes. Subtype 1 showed thickening cingulate gyrus, thinning occipital pole, and atrophic subcortical nuclei. Subtype 2 exhibited widespread cortical thinning across the frontal, parietal, temporal, and limbic regions, but enlarged subcortical nuclei. Genes underlying two subtypes were both enriched for neurodevelopmental diseases. However, subtype 1 was associated with synaptic transmission, and subtype 2 was related to cytoskeletal and neuronal connectivity. ConclusionThis study reveals individual-level anatomical deviations and transcriptomic heterogeneity in early-onset schizophrenia. The findings provide an individualized brain-gene coupling framework for understanding pathophysiology of schizophrenia during brain development.

molecular biology↗

Inflammation in schizophrenia: Peripheral interleukin-6 levels-related disease-specific functional activity abnormalities

BackgroundPeripheral inflammation is implicated in the pathophysiology of schizophrenia, but how inflammatory signals map onto the large-scale brain organization remains incompletely understood. MethodsWe applied a supervised multimodal fusion approach guided by interleukin-6 (IL-6) to gray matter volume (GMV) and resting-state regional homogeneity (ReHo) from a population-based discovery cohort in the UK Biobank. Brain components related to IL-6 were identified and then projected onto an independent schizophrenia cohort to examine their relevance to the disease. Imaging-transcriptomic analyses using the Allen Human Brain Atlas characterize the molecular substrates underlying the disease-relevant pattern. ResultsTwo ReHo components were significantly associated with plasma IL-6, while no GMV components showed robust IL-6 correlations. One of the components (ReHo IC4) exhibited a conserved functional pattern characterized by enhanced visual synchrony and reduced synchrony in the medial prefrontal cortex. This pattern remained unchanged in both the healthy controls and patients. In contrast, another component (ReHo IC8) showed increased synchrony in the default mode network and reduced synchrony in sensorimotor networks, and its loadings were significantly elevated in patients with schizophrenia. Imaging-transcriptomic analysis revealed the molecular architecture of this disease-amplified pattern. The default mode region was enriched in synaptic signaling pathways, while the sensorimotor region was linked to mitochondrial bioenergetic processes; both patterns significantly enriched with gene sets related to schizophrenia. ConclusionsThis study identified an IL-6-associated functional brain pattern that is amplified in schizophrenia, linking peripheral inflammation to disease-specific network dysregulation. The findings provide a systems-level framework for understanding how peripheral inflammation interacts with large-scale brain network activities in schizophrenia.

neuroscience↗

Noncanonical loops regulated by EMF1 and cohesin-associated factors shape the distinct 3D genome architecture in plants

In mammals, cohesin-mediated chromatin loop extrusion is blocked at boundaries, where CTCF, WAPL, and PDS5s co-bind and regulate cohesin, establishing an impermeable barrier with no exceptions. In contrast, our study revealed that in Arabidopsis, some noncanonical contacts have emerged between the boundary flanking regions, which suggest that cohesin is not absolutely blocked but enables sliding beyond boundaries. We identified these interactions as noncanonical loops and clarified their regulatory proteins. Firstly, the plant-specific boundary binding protein EMF1 is essential for noncanonical loops formation. Surprisingly, although both Arabidopsis WAPLs and PDS5s inhibit loop extension as mammals, PDS5s do not co-bind and cooperate with WAPLs at boundaries. Instead, PDS5s bind to boundary-flanking regions enriched with H3K4me1 through their Tudor domains, restricting further extension of noncanonical loops. Consequently, pds5a/b/c mutants lose noncanonical loops, resulting in emergence of larger canonical loops but anchored on boundaries and co-upregulation of anchored gene pairs. Collectively, our findings reveal that the plant-specific noncanonical loop, regulated by plant-specific EMF1 and PDS5 proteins, is the fundamental structure of the distinctive chromatin organization of plants, which provides novel mechanistic insights into eukaryotic chromatin architecture regulation.

plant biology↗

MOSAIC: A Structured Multi-level Framework for Probabilistic and Interpretable Cell-type Annotation

Accurate cell-type annotation is a foundational task in single-cell RNA sequencing analysis, yet remains fundamentally challenged by cellular heterogeneity, gradual lineage transitions, and technical noise. As single-cell atlases expand in scale and resolution, most existing annotation approaches operate at a single analytical level and encode cell identity as fixed categorical labels, limiting their ability to represent uncertainty, mixed biological states, and population-level structure. Here we introduce MOSAIC (Multi-level prObabilistic and Structured Adaptive IdentifiCation), a structured multi-level annotation framework that integrates cell-level marker evidence with cluster-level population context within a unified probabilistic system. Rather than treating annotation as an independent per-cell prediction task, MOSAIC formulates cell-type assignment as a coordinated multi-level inference process, in which probabilistic evidence at the single-cell level is aggregated, constrained, and refined by population context. MOSAIC integrates direction-aware marker scoring with dual-layer probabilistic representation and adaptive cross-level refinement, enabling uncertainty to be quantified and propagated across biological scales. This design yields coherent annotations that preserve fine-grained single-cell variation while maintaining population-level consistency, and allows ambiguous or transitional states to be represented explicitly rather than collapsed into hard labels. Across six diverse tissues and under controlled dropout perturbations, MOSAIC consistently matches or outperforms representative marker-based, reference-based, and machine-learning annotation methods. Beyond accuracy, MOSAIC provides structured uncertainty estimates and coherent population-level structure, enabling the identification of stable intermediate cell states that arise from gradual lineage transitions rather than technical noise. Together, MOSAIC advances cell-type annotation from a single-level classification task to a structured multi-level inference problem, and establishes a general, interpretable, and uncertainty-aware computational framework for large-scale single-cell analysis.

bioinformatics↗

Clonal morphology-guided combination therapies overcome heterogeneity-driven drug tolerance

Tumor heterogeneity plays a critical role in tumor relapse and the development of drug resistance. Current personalized strategies, based on genetic profiling or bulk tumor drug sensitivity testing, offer limited clinical value as they overlook clonal heterogeneity. Here, through establishing primary tumor cell cultures from multiple metastatic sites, we observed that tumor cells exhibit high morphological plasticity and readily form distinct clonal morphologies during monoclonal expansion. Moreover, these heterogeneous clones displayed distinct tumorigenic and histological traits in orthotopic models, which may imply their differing clinical relevance in tumor progression. We also found that clonal morphological heterogeneity was exhibited by both established cell lines and primary lines derived from chemically induced tumor models. Subsequently, we analyzed the drug sensitivity profiles of tumor clones and identified clone-specific sensitive drugs. Despite limited in vitro synergy in pairwise combinations, both in vitro and in vivo assays confirmed their potent, clone-selective inhibition, suggesting rational drug combinations can precisely target distinct clonal populations. Taken together, Collectively, our findings propose that a heterogeneity-informed drug selection paradigm, enabled by rapid clonal morphology analysis of patient-derived cells, can be used to prevent recurrence and overcome resistance. Graphic Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=200 SRC="FIGDIR/small/703021v1_ufig1.gif" ALT="Figure 1"> View larger version (55K): org.highwire.dtl.DTLVardef@1db607dorg.highwire.dtl.DTLVardef@19bbcd4org.highwire.dtl.DTLVardef@18a3355org.highwire.dtl.DTLVardef@304794_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LITumor cells develop distinct morphologies during clonal expansion. C_LIO_LIDistinct morphologies serve as simple markers of tumor heterogeneity. C_LIO_LIDistinct clonal morphology defines a unique drug-response profile. C_LIO_LIClone-selective drug combinations combat heterogeneity-driven resistance. C_LI

cancer biology↗

An AI-Native Biofoundry for Autonomous Enzyme Engineering: Integrating Active Learning with Automated Experimentation

The engineering of enzymes with novel functions is a cornerstone of synthetic biology but remains bottlenecked by the fragmentation between computational design and physical execution. While "self-driving" laboratories promise to resolve this, existing systems often rely on rigid, device-specific scripts that lack the flexibility to handle complex, evolving scientific tasks. Here, we report an AI-native autonomous biofoundry that fundamentally redefines laboratory automation through a "cloud-edge synergistic" architecture. The platform features an Agent-Native control system powered by Large Language Models (LLMs) and the Model Context Protocol (MCP), which bridges the semantic gap between abstract scientific intent and heterogeneous hardware execution. This architecture enables non-experts to orchestrate the entire Design-Build-Test-Learn (DBTL) cycle via natural language. By integrating deep phylogenetic mining, zero-shot protein language models (ESM-2), and supervised active learning, our system efficiently navigates rugged fitness landscapes. As a rigorous proof of concept, we applied this platform to evolve a Family B DNA polymerase for CoolMPS sequencing, a task requiring the incorporation of non-natural 3-blocked nucleotides. In just three autonomous rounds, the platform achieved a hit rate of >66% and identified variants with a 37% reduction in sequencing error rate compared to a commercial reference. This work demonstrates that AI-native infrastructures can not only accelerate trait evolution by orders of magnitude but also provide a scalable, brand-agnostic paradigm for the future of automated scientific discovery.

bioengineering↗

Lactate treatment improves brain biochemistry and cognitive function in transgenic Alzheimer's and wild-type mice

Lactate, a well-known metabolite and signalling molecule, holds therapeutic potential for neurodegenerative diseases. Here, we investigated the effects of chronic lactate treatment on cognition and molecular biomarkers in the 5XFAD mouse model of Alzheimers disease (AD) and in wild-type (WT) controls using behavioural testing alongside proteomic and transcriptomic analyses. Mice received lactate or vehicle injections 4 days per week for 11 weeks, with behavioural testing before and after the treatment period. Lactate improved working memory in late-treated AD mice, without eliciting anxiety-like behaviour. At the molecular level, lactate reduced Il1b expression, and in a sex-dependent manner, normalised NEFL, and enhanced synaptic integrity proteins (OPCML, PPFIA2, STXBP3, SYT1, VGLUT2, VSNL1) in AD mice, while also augmenting mitochondrial regulators (ATP5G2, GRPEL1, SLC25A23) across genotypes. Notably, lactate upregulated low-abundance ionotropic glutamate receptor mRNAs (Grik3, Grin2c, Grid2ip) in female AD mice, indicating enhanced glutamatergic signalling. In WT mice, lactate increased expression of neurotrophic factors (Bdnf, Igf1, Vegfa), anti-inflammatory cytokines (Il4 and Il13), and the neuronal lactate transporter Mct2, suggesting promoted neuronal resilience. Together, these findings indicate that lactate treatment can mitigate cognitive decline and enhance molecular pathways of resilience in AD, warranting larger, age-stratified studies to validate its therapeutic potential and elucidate underlying mechanisms.

animal behavior and cognition↗

Clove Aqueous Extract Triggers a Multi-Organellar Stress Crisis through Lysosomal Destabilisation and Mitochondrial Hyperpolarisation to Suppress Patient-Derived Ovarian Cancer Cells

Ovarian cancer (OC) remains a lethal malignancy with limited therapeutic options, underscoring the need for the identification of novel agents. Natural products like clove (Syzygium aromaticum) have shown promising anti-cancer activity, but their mechanism in OC is poorly understood. This study investigates the anti-tumour effects and underlying mechanisms of a clove aqueous extract (CAE) on a panel of patient-derived OC cells. We found that CAE significantly inhibited cellular proliferation and induced cell death in a time-and dose-dependent manner. Mechanistically, CAE induced profound cellular stress, activating the transcription factor ATF-2. This was accompanied by a significantly increased lysosomal stress response, as evidenced by increased lysosomal mass/acidity, and a pathogenic hyperpolarisation of the mitochondrial membrane potential ({Delta}{Psi}m). The bioenergetic crisis induced as a consequence resulted in a sharp reduction in cellular oxygen consumption rate (OCR). Notably, the sensitivity to CAE-induced lysosomal and mitochondrial dysfunction varied across cell lines, revealing distinct phenotypic responses. Our results demonstrate that clove extract exerts its anti-tumour effects by orchestrating a multi-organellar stress response, positioning lysosomal disruption as a central event in its mechanism of action. This study provides a strong rationale for the further development of clove-based interventions for OC.

cancer biology↗

The RNA Editome of Esophageal Squamous Cell Carcinoma Identifies an ADAR1-CDK13 Editing Feedback Loop Mediating cGAS-STING Activation in Early Tumorigenesis

ObjectiveRNA adenosine-to-inosine (A-to-I) editing, catalyzed by adenosine deaminases acting on RNA (ADARs), is a pervasive post-transcriptional mechanism that expands transcriptomic and proteomic diversity. However, the global landscape of RNA A-to-I editing, as well as its functional and clinical significance in esophageal squamous cell carcinoma (ESCC), remains largely unexplored. This study aimed to systematically characterize the RNA editome of ESCC and elucidate its biological and clinical significance. MethodsWhole-transcriptome sequencing was performed on 121 primary ESCC tumors, with or without lymph node metastasis, together with matched normal tissues, to construct a high-resolution RNA editome. ADAR1-regulated RNA editing events were identified, and their functional consequences were investigated using integrated transcriptomic, phosphoproteomic, and RNA immunoprecipitation sequencing (RIP-seq) analyses. Associations between CDK13 editing, cGAS-STING-interferon-stimulated gene (ISG) signaling, and patient survival were further evaluated. ResultsA total of 222,020 high-confidence RNA editing sites were identified, of which approximately 98% were A-to-I events, including 124,486 ESCC-specific edits predominantly enriched in introns, 3' untranslated regions, and non-coding RNAs, highlighting a pervasive post-transcriptional regulatory layer. RNA A-to-I editing was extensively remodeled and globally up-regulated in non-metastatic ESCC, whereas only minimal changes were observed during lymph node metastasis, indicating that RNA editing alterations predominantly occur during early tumorigenesis. CDK13 emerged as a recurrent ADAR1 target, with RNA editing inversely correlated with CDK13 expression. ADAR1-mediated CDK13 editing established a positive feedback loop associated with enhanced interferon-stimulated gene (ISG) signaling and poorer survival in non-metastatic ESCC. Mechanistically, partial attenuation of CDK13 induced chronic, tumor cell-intrinsic activation of the cGAS-STING-ISG pathway. Integrated multi-omics analyses further revealed that CDK13 regulates phosphorylation networks governing cytoskeleton organization, intracellular trafficking, RNA homeostasis, and immune signaling. ConclusionRNA A-to-I editing represents a dynamic regulatory mechanism driving early ESCC progression and remodeling tumor cell-intrinsic immune signaling. ADAR1-mediated editing of CDK13 provides a mechanistic link between RNA editing and cGAS-STING-ISG pathway activation, revealing potential therapeutic vulnerabilities and supporting its utility as an early prognostic biomarker in ESCC.

cancer biology↗

Contrasting controls on tree methane emissions in upland and wetland forests

Trees can produce, consume, transport, and emit methane (CH), yet the environmental controls and mechanisms underlying these fluxes remain poorly understood. We combined 1,640 stem-chamber observations (2023-2025) with tower-based meteorology, soil moisture and temperature networks, water table monitoring, and non-destructive tomography to test how hydrology, energy balance, species identity, and internal wood condition regulate stem CH flux. Wetland trees emitted approximately 40-fold more CH than upland trees (1.96 vs. 0.05 nmol m-{superscript 2} s-{superscript 1}). At the wetland, a three-way interaction between soil temperature, water table depth, and species explained 65% of flux variance, consistent with soil-derived CH transport through stems. The wetland specialist Nyssa sylvatica emitted an order of magnitude more CH than co-occurring generalists, likely reflecting flood-tolerance adaptations that enhance gas transport. In contrast, upland fluxes showed minimal environmental control (R{superscript 2} < 9%), with most variance occurring as unexplained temporal variation within individual trees--a pattern suggesting competing methanogenic and methanotrophic processes operating near equilibrium. Internal wood condition, assessed via acoustic and electrical resistance tomography, had opposite effects across sites: decay increased emissions in upland trees, likely by creating anaerobic microsites for in situ production, while decay decreased net emissions in wetland trees, likely by impairing transport of soil-derived CH more than it enhanced in situ production. Together, these results indicate that the dominant controls on tree CH flux differ fundamentally between wetland and upland forests, underscoring the need to represent hydrologic setting, species composition, and tree condition when scaling forest CH contributions to regional budgets.

ecology↗

Programmable artificial RNA condensates in mammalian cells

Artificial biomolecular condensates have emerged as powerful tools to control cellular behaviors. Here we introduce a method to build artificial condensates within living mammalian cells through the design of modular RNA motifs formed by a single, short strand of RNA. These condensates emerge spontaneously, creating RNA-rich compartments that remain separated from their surrounding environment. The RNA sequences include stem-loop domains that fold as the RNA is transcribed, and then condense in the nucleus and cytoplasm through loop-loop interactions. These sequences can be optimized and diversified, enabling the generation of distinct, non-mixing condensate populations and the programmable control of their subcellular localization. The RNA motifs can also be modified to recruit small molecules, proteins, and RNA molecules in a sequence-specific manner to the RNA-rich phase. By introducing additional RNAs that link two distinct types of condensates, we can create droplets with multiple subcompartments, whose organization can be controlled by tuning the stoichiometry of different RNA sequences. These artificial condensates provide a versatile platform for studying and manipulating molecular functions inside living cells.

synthetic biology↗

Organoid-Based Transcriptomics Indicate IFIT-Associated Immune Modulation during Cryptotanshinone Treatment in Bladder Cancer

Bladder cancer (BC), particularly muscle-invasive and metastatic disease, remains a major clinical challenge despite recent advances in immunotherapy. In this study, we aimed to identify a promising antitumor compound from five candidate small molecules and to explore its potential roles in BC progression. Through antiproliferative screening, cryptotanshinone (CTS) was identified as the promising candidate. Using both two-dimensional BC cell lines and three-dimensional bladder tumor organoid models, we comprehensively evaluated the effects of CTS on cell proliferation, migration, apoptosis, and organoid growth. To further explore the underlying mechanisms, transcriptomic sequencing based on bladder cancer organoid models, protein-protein interaction network analysis, and public databases (TCGA-BLCA, TIMER, and TISIDB) were integrated to examine immune-related pathways and potential molecular targets associated with CTS. GeneMANIA network prediction and molecular docking analyses were subsequently performed to investigate upstream regulatory networks and the potential interactions between CTS and key components of the cGAS-STING-IFN-I-JAK-STAT signaling pathway. Integrative analyses suggested that IFIT1, IFIT2, and IFIT3 may function as immune-associated genes potentially linked to BC progression, patient prognosis, immune cell infiltration, and PD-1/PD-L1 expression. Molecular docking results suggested that CTS may interact with core regulatory proteins within the cGAS-STING-IFN-I-JAK-STAT pathway, potentially influencing IFIT transcriptional regulation. Collectively, these findings indicate that CTS exhibits measurable antitumor and immunomodulatory effects, which may be associated with modulation of the cGAS-STING-IFN-I-JAK-STAT-IFIT signaling axis, supporting its potential as a small-molecule candidate for bladder cancer.

cancer biology↗

RasGRP1 agonists stimulate P-TEFb biogenesis via MEK-ERK-mTORC1 signaling to reverse HIV latency with minimal CD4 downregulation

Reactivation of latent HIV to facilitate clearance of persisting infected cells requires identifying non-toxic latency-reversing agents (LRAs) that activate P-TEFb, a cellular transcription factor essential for efficient HIV RNA synthesis. Diacylglycerol (DAG)-mimicking PKC agonists induce P-TEFb to reverse HIV latency mainly through a PKC-independent RasGRP1-Ras-Raf-MEK-ERK1/2 pathway, but also elicit global T-cell activation and a drastic downregulation of CD4 receptors. Here, we demonstrate that synthetic DAG-indololactones, which preferentially bind RasGRP1 over PKC by up to 60-fold, strongly induce posttranscriptional P-TEFb expression in memory CD4+ T cells via MEK-ERK1/2-mTORC1 signaling without triggering T-cell activation markers and with minimal CD4 loss. Elevation of T-cell activation markers by natural and synthetic PKC agonists proceeds through MEK-ERK1/2 but is independent of mTORC1 activity. Combinations of the DAG-indololactone 2A127 and HDAC inhibitors synergistically reactivate latent HIV in a primary T-cell model and CD4+ T cells from treated individuals. These findings suggest that a combination LRA approach targeting P-TEFb production through RasGRP1-ERK1/2-mTORC1 signaling and the epigenetic activation of proviral HIV can efficiently and safely reverse HIV latency.

cell biology↗

When CycloneSEQ meets Oxford Nanopore Technologies: a performance comparison of contemporary nanopore DNA sequencing platforms

Nanopore sequencing enables direct analysis of native DNA modifications, but these modifications can also introduce systematic basecalling errors. Here, we investigated how bacterial DNA methylation contributes to nanopore substitution errors using matched native whole-genome sequencing (WGS) and methylation-depleted whole-genome amplification (WGA) datasets from six bacterial species across CycloneSEQ (CS) and Oxford Nanopore Technologies platforms (ONT). Adenine-to-guanine (A2G) and guanine-to-adenine (G2A) substitutions were consistently enriched across species, nanopore platforms, sequencing configurations, and basecalling models, indicating a shared nanopore-associated substitution bias. This enrichment remained detectable in WGA reads, whereas native WGS reads showed a further increase. Using independent PacBio methylation profiling, we found that the WGS-associated substitution excess was strongly concentrated around bacterial methylation motifs and was minimal in non-motif regions. The magnitude and substitution pattern of these errors varied among motifs and sequencing platforms. At a subset of motif-associated positions, alternative-base fractions exceeded 50%, producing SNP-like signals. In ONT data, 28 WGS-specific calls survived the applied SNP-calling filters, all within PacBio-supported methylation contexts, and most showed significant strand imbalance. Together, these results identify a shared A2G/G2A substitution bias in all nanopore datasets and support a methylation-associated increase in these errors near bacterial methylation motifs, with some loci producing SNP-like artifacts.

bioinformatics↗

Development of Integrin α5β1-targeted PET/NIR imaging probes for glioblastoma intraoperative navigation and intracavity targeted radionuclide therapy

Incomplete extent of tumor resection is the major factor of glioblastoma recurrence, leading to its poor prognosis. Developing therapies that enable the minimal tumor cell remnant during surgical resection is a major challenge to combat this aggressive cancer. This study develops a glioblastoma integrin 5{beta}1-selective peptide binder through series strategy screening and labeling it with 68Ga, indocyanine green (ICG), or 177Lu for efficacious multimodal treatment. This strategy combines positron emission tomography (PET) imaging for preoperative diagnosis, intraoperative NIR-II fluorescence-guided surgery for maximal tumor resection, and followed by intracavity targeted radionuclide therapy for elimination of residual tumor cells. We identified GR, with five arginine mutation, exhibiting superior integrin 5{beta}1 binding affinity and brain penetration. [68Ga]GR demonstrated substantial tumor uptake and prolonged retention time in both mouse models and tissues from glioblastoma patients. The guidance of ICG-GR achieved accurately intraoperative tumor imaging and maximal tumor resection in orthotopic mouse glioblastoma models. Notably, combining intracavity administration of [177Lu]GR following ICG-GR guiding resection markedly inhibited tumor growth and reduced possibility of tumor recurrence compared with surgery alone (unguided or ICG-GR-guided) or unguided surgery followed by [177Lu]GR. Therefore, we have reported the integrin 5{beta}1-targeted radionuclide and optical agents for maximal elimination of tumor cells during surgical resection in glioblastoma patients. HIGHLIGHTSO_LIGR is a glioblastoma-specific peptide with both favorable binding affinity superior brain penetration. C_LIO_LIICG-GR is a glioblastoma-targeted NIR probe enabling maximal surgical resection. C_LIO_LIICG-GR-guided surgery with [177Lu]GR-based adjuvant therapy allows robust elimination of tumor cells. C_LI

cancer biology↗

MTFP1 preserves β-cell cristae structure and bioenergetics to ensure insulin release and glucose homeostasis

Pancreatic {beta}-cells are uniquely dependent on mitochondrial metabolism to couple glucose sensing to insulin secretion, a process impaired in diabetes. Mitochondrial fission process 1 (MTFP1) is an inner mitochondrial membrane protein that plays pleiotropic, tissue-specific roles in mitochondrial function and dynamics. Our previous work has identified Mtfp1 mRNA as a target for miR-125b, a microRNA that negatively regulates insulin secretion from {beta}-cells. Nevertheless, the function of MTFP1 in these cells remained unexplored. Here, we show that MTFP1 is essential for normal glucose-stimulated insulin secretion (GSIS) in mouse and human cell lines and islets, and that mice with {beta}-cell-specific elimination of MTFP1 develop glucose intolerance. Whereas {beta}-cell survival and mitochondrial content were unaffected, oxidative phosphorylation and ATP production were sharply lowered. These changes were accompanied by disruption of mitochondrial cristae structure and a reduced contact surface with the endoplasmic reticulum, providing a mechanistic basis for defective stimulus-secretion coupling. Conversely, MTFP1 overexpression in mouse and human islets sufficed to improve mitochondrial respiration and GSIS. Finally, MTFP1 downregulation blocked the positive effects of miR-125b elimination in GSIS and mitochondrial respiration, unveiling MTFP1 as a downstream effector of miR-125b. Together, our findings identify MTFP1 as a critical regulator of {beta}-cell mitochondrial architecture and function, necessary for efficient insulin secretion and glucose homeostasis, and a potential therapeutic target to enhance {beta}-cell bioenergetic resilience in diabetes.

cell biology↗

Unlocking Ultrasensitive Phosphoproteomics of Nanoscale Samples: A Rapid IMAC Enrichment Platform Using Ti-PAN Tip

Protein phosphorylation is a critical mechanism in cellular signal transduction, playing essential roles in various cellular processes. However, significant challenges of their low abundance, high dynamic range, and complexity are especially prominent for accurate phosphoproteome analysis in nanoscale samples, such as oocytes, where misregulation of phosphorylation can lead to infertility. In this study, we developed a novel phosphopeptide enrichment tip (Ti-PAN) using highly hydrophilic textile PAN fibers, enabling rapid in-situ one-tip IMAC enrichment in just 8 minutes. This approach not only minimizes sample loss but also enhances analytical sensitivity and is easily adaptable to automation for high-throughput applications, demonstrating excellent recovery (>94%) and outstanding selectivity for phosphopeptides with remarkable resistance to interference up to 1:5000. By integrating it with a compatible sample preparation workflow based on n-dodecyl {beta}-D-maltoside (DDM) lysis with the high-sensitivity MS data acquisition method of turboDDA, comprehensive mapping of phosphosites in microsamples was achieved, including those from the ERK interactome, mouse brain slices, and oocytes. Using this approach, we identified 2,139 to 11,296 phosphosites across 645 to 2,168 phosphoproteins from samples ranging from 100 to 100,000 cells. Furthermore, we successfully applied this strategy to analyze the phosphoproteome of mouse oocytes at different developmental stages, using as few as 5 oocytes per sample. This led to the identification of 2,709 phosphosites on 701 phosphoproteins, revealing several key kinases involved in meiotic resumption and oocyte maturation, including STK4 (serine/threonine kinase 4) and DYRK3 (dual specificity tyrosine phosphorylation-regulated kinase 3). To our knowledge, this represents the deepest coverage of phosphoproteomes from such minimal oocyte material reported to date, offering valuable mechanistic insights into developmental controls during oocyte maturation. This Ti-PAN-based method provides a robust, versatile, and automatable platform for large-scale, highly sensitive phosphopeptide enrichment, substantially advancing phosphoproteomic studies in complex biological systems.

biochemistry↗

Structural Insights into Single-Stranded DNA Recognition and Modified Substrate Tolerance in an Engineered Terminal Deoxynucleotidyl Transferase

Terminal deoxynucleotidyl transferase (TdT) is the cornerstone enzyme for de novo enzymatic DNA synthesis (EDS), promising to overcome the length and sustainability limitations of traditional phosphoramidite chemistry. We previously identified a highly active TdT ortholog from Zonotrichia albicollis (ZaTdT) and engineered a variant (R335L/K337G) capable of efficiently incorporating 3-aminooxy (3-ONH2) reversible terminators. However, the atomic-level mechanism by which these engineered mutations alter substrate specificity has remained elusive. Here, we present the high-resolution (2.20 [A]) crystal structure of the engineered ZaTdT in complex with a single-stranded DNA primer. Structural analysis reveals a conserved catalytic core anchored by a hydrophobic platform (Phe110/Phe257/Trp308) that stabilizes the primer. Crucially, comparative modeling with the homologous murine TdT ternary complex demonstrates that the engineered mutations (corresponding to L190/G192 in the crystal structure) disrupt a rigid salt-bridge network at the active site entrance. This electrostatic remodeling not only reduces local positive charge but also expands the catalytic pocket depth from 3.8 [A] to 5.8 [A]. This specific spatial expansion provides the structural rationale for the accommodation of bulky 3-blocking groups, validating our rational design strategy and paving the way for next-generation long-read DNA synthesis.

biochemistry↗