bioRxiv Science⌕ Search

Biology subjects

Mi, Y.

Publications and source records attributed to Mi, Y..

At least 19 recordsLinked to original sources

Vulnerability of triple negative breast cancer to daraxonrasib pan-RAS(on) inhibition

Triple-Negative Breast Cancer (TNBC) is a clinical subtype where aberrant expression of receptor tyrosine kinases (RTKs) leads to the activation of the RAS-RAF-MEK-ERK pathway contributing to tumor progression. Therapies targeting components of the RAF-MEK-ERK pathway in TNBC have been disappointing due to rapid onset of adaptive reprogramming of the RTK landscape leading to pathway reactivation. To overcome the dynamic heterogeneity of RTK expression and their convergence in activating RAS, treatment with the pan-RAS(on) inhibitor daraxonrasib (RMC-6236), which inhibits RAS-GTP regulation of RAF kinases, inhibited proliferation independent of TNBC kinotype or oncogenic RAS mutation in three of four TNBC cell lines in vitro and two patient-derived TNBC xenografts in mice. Daraxonrasib in combination with the MEK inhibitor trametinib prevented reactivation of the RAF-MEK-ERK pathway observed with each inhibitor alone and further enhanced inhibition of tumor growth in TNBC cell lines and xenografts. Inhibiting pan-RAS(on) RAS-GTP, with daraxonrasib, alone or in combination with a MEK inhibitor, provides a new strategy for the treatment of TNBC that inhibits RTK activation of the RAS-RAF-MEK-ERK pathway and tumor proliferation.

cancer biology↗

NEURA: An agentic system for autonomous neuroimaging workflows

Neuroimaging research depends on heterogeneous software, multimodal data and multistage statistical workflows. Large language model (LLM)-based agents offer a route to automate these workflows, but their susceptibility to hallucination limits their credibility in scientific use. Here we introduce NEURA, a proof-carrying framework for hallucination-resistant neuroimaging automation. NEURA converts free-text research questions and neuroimaging datasets into executable analysis plans, validated outputs and structured reports. The system combines disease- and tool-aware planning with a deterministic verification layer inspired by formal proof: before any claim is retained for reporting, it must be checked against tool-derived evidence and domain axioms. On NeuroEval, an expert-curated benchmark of 110 neuroimaging tasks, NEURA achieved 89.5% planning accuracy, a 30.5% improvement over direct LLM queries. In a controlled hallucination-injection experiment, the verification layer detected all the injected error classes under the specified axiom bank and trust assumptions, with no false positives. In case studies of spinocerebellar ataxia type 3, NEURA reproduced cerebellar atrophy and abnormal diffusion patterns consistent with established pathology and independent expert analyses. Together, these findings show that coupling domain-grounded agency with proof-carrying verification can turn LLM-driven workflow automation from probabilistic self-checking into auditable scientific computation.

neuroscience↗

Whole-Tissue Distribution Analysis for Visualization of Nanoplastics in the Mouse Brain

Nanoplastics (NPs) are increasingly recognized as environmental contaminants and have been detected in diverse biological tissues; however, their biodistribution in complex organs remains poorly understood. Conventional section-based imaging restricts spatial context and volumetric analysis, making it challenging to map NP distribution in structurally complex organs such as the brain, even with fluorescent labeling. To address these limitations, we developed an integrated workflow combining tissue optical clearing (SeeDB2G) with light-sheet fluorescence microscopy (LSFM), enabling three-dimensional visualization of fluorescently labeled polystyrene (PS) NPs in neonatal mouse brains. At postnatal day 0 - a critical window of heightened vulnerability due to immature barrier systems and rapid neurodevelopment - pups were orally administered spherical PSNPs of 50 or 500 nm. Fluorescence stereoscopic imaging revealed pronounced organ-level accumulation of 50 nm PSNPs in the intestine, liver, kidney, and brain, compared with markedly lower signals from 500 nm PSNPs 24 h post-exposure. Optical clearing rendered the entire brain transparent while preserving fluorescence, allowing LSFM to accurately assess regional PSNP accumulation without sectioning. This workflow enabled whole-brain visualization of size-dependent NP uptake, with 50 nm PSNP detected throughout the brain and the highest accumulation observed in the thalamus and brainstem. Although the current implementation relies on fluorescent labeling and model NPs, this approach provides a scalable platform for whole-organ biodistribution analysis and lays the foundation for mechanistic studies of barrier permeability, developmental vulnerability, and organ-specific interactions.

pharmacology and toxicology↗

Real-time functional connectivity-based neurofeedback of the DLPFC-amygdala pathway during threat-exposure attenuates anxiety

BackgroundAdaptive regulation of negative emotion is vital for mental health and dysregulations in this domain contribute to the major mental disorders, including anxiety and depression. On the neural level, efficient emotion regulation has been linked to functional communication between the dorsolateral prefrontal cortex (DLPFC) and the amygdala. Gaining voluntary control over this pathway may present an effective strategy for potentiating emotion regulation. ObjectiveAgainst this background, we developed a novel connectivity-based real-time fMRI (rt-fMRI) neurofeedback (NF) training that enables individuals to gain volitional control over the DLPFC-amygdala pathway during exposure to threatening stimuli. MethodsThe study employed a pre-registered, randomized, sham-controlled design with the experimental group (n = 22) receiving real-time NF information on connectivity between the right DLPFC and the amygdala during threat exposure and the sham control group (n = 23) receiving connectivity NF from a circuit not related to emotion regulation. The ability to maintain regulatory control in the absence of feedback was assessed after four NF runs. Primary outcomes included functional connectivity of the target pathway, as well as anxiety scores. ResultsThe results demonstrate that successful acquisition of self-regulation of the rDLPFC-amygdala top-down regulatory circuit in the experimental NF group facilitated attenuation of anxiety. ConclusionIn summary, our findings suggest that real-time fMRI neurofeedback (rtfMRI-NF) allows to volitionally enhance rDLPFC-amygdala connectivity, and in turn reduces negative emotional states, rendering the training a promising neurotechnology intervention for mental disorders.

neuroscience↗

Machine Vision Enabled Lateral Flow Immunoassay Using Functionalized Gold Nanoparticles for Point-of-Care Cardiac Biomarker Detection

Acute myocardial infarction (AMI) remains one of the most prevalent and fatal cardiovascular disease. Given the critical diagnostic significance of cardiac troponin I (cTnI) and myoglobin (Myo) in AMI, there is an urgent clinical demand for rapid and accurate detection methods to improve patient outcomes and reduce mortality. To meet this need, we developed a sensing platform that integrates functionalized gold nanoparticle-based lateral flow immunoassay (AuNPs-LFIA) with a machine vision model, enabling rapid quantitative detection of cTnI and Myo. By covalently conjugating antibodies to gold nanoparticles (AuNPs@Ab), we achieved greater probe specificity and stability. The integration of machine vision algorithms allowed quantitative readouts within 8 minutes, a 46.7% improvement of the detection time compared to conventional methods (15 minutes). The platform achieved limits of detection of 0.224 ng/mL for Myo and 0.071 ng/mL for cTnI, with excellent correlation to commercial kits (R2 > 0.99). Overall, these results demonstrate that machine vision-enhanced AuNPs-LFIA offers an efficient, sensitive and reliable strategy for point-of- care testing (POCT) in cardiovascular diagnostics, particularly in resource-limited settings.

bioengineering↗

Post-inhibitory rebound firing drives hypothalamic activation for male mating

Many behaviorally relevant limbic circuits are dominated by inhibitory connections, raising the question of how neuronal activation arises in such contexts. In male mating, both activation of mPOA and its inhibitory inputs are essential--a paradox previously ascribed to disinhibition. Here, we show that the mPOA largely lacks local inhibitory circuits, arguing against disinhibition. Instead, in vivo recordings reveal that mount-active mPOA neurons are suppressed prior to behavioral onset, and this inhibition negatively correlates with subsequent activation, consistent with post- inhibitory rebound firing (PIR). A biologically plausible conductance-based model demonstrates that synaptic inhibition interacts with T-type Ca{superscript 2} currents -- the ionic basis of PIR -- to promote mPOA neuron firing. Experimentally, bidirectional manipulations of mPOA T-type Ca{superscript 2} channels confirm this mechanism: knockdown reduces PIR and impairs male mating, while overexpression enhances mating. Together, these results identify PIR as a critical mechanism by which inhibition promotes activation in limbic circuits to drive male mating.

neuroscience↗

TP53 mutations drive therapy resistance via post-mitochondrial caspase blockade

Acute myeloid leukemia (AML) is a heterogeneous disease characterized by a broad spectrum of molecular alterations that influence clinical outcomes. TP53 mutations define one of the most lethal subtypes of acute myeloid leukemia (AML), driving resistance to nearly all available treatment modalities, including venetoclax plus azacitidine (VenAza). Yet, the molecular basis of this resistance, beyond affecting transactivation of BCL-2 family genes, has remained elusive. Here, we demonstrate that VenAza treatment leads to reduced transcriptional upregulation of the p53 signaling pathway in TP53 mutant/deficient AML compared to wild-type AML. Functionally, TP53 mutant/deficient AML exhibits selective failure in apoptosis induction rather than impaired G1 arrest or senescence. Despite inhibition of pro-apoptotic BAX and selective enrichment for MCL-1 in TP53 mutant isogenic AML cells, compensatory upregulation of BIM preserved functional mitochondrial outer membrane permeabilization (MOMP). TP53 mutant primary AML tumors at baseline also had retained capacity for MOMP. Instead, TP53 mutant AML exhibited disruption in caspase-3/7 activation to evade apoptosis after VenAza therapy - decoupling the mitochondrial and executioner phases of apoptosis. Importantly, this "post-MOMP brake" is not a bystander effect but itself a driver of VenAza and chemotherapy resistance in TP53 mutant/deficient AML. This previously unrecognized mechanistic insight shifts the focus from mitochondrial priming to terminal caspase blockade in TP53 mutant AML and opens the door for urgently needed therapeutic strategies that reignite apoptosis at its execution point.

cancer biology↗

Human meibomian gland organoids to study epithelial homeostasis and dysfunction

Meibomian glands (MGs) are holocrine glands that secrete lipids to maintain the homeostasis of ocular surface, and their dysfunction leads to dry eye disease. Herein, we established long-term 3D organoid culture for murine and human MGs, which retained the cell lineages and lipid-producing ability. The organoids mimicked the drug treatment responses and generated functional MGs after orthotopic transplantation. Inspired by organoid cultures, we found FGF10 eye drops could rescue all-trans retinoic acid-induced MG dysfunction in mice. Besides, nicotinamide uniquely hampered the human MG organoid expansion by inhibiting FGF10 signaling. Single-cell atlas and lipidome not only aligned the delineated cell types and featured lipids between human MGs and organoids, but highlighting MAPK signaling inhibition enhanced acinar cell differentiation and functional maturation of MG organoids. In summary, this study established an organoid platform to explore epithelial homeostasis and dysfunction of MGs, facilitating drug development and regenerative medicine for dry eye disease.

cell biology↗

Targetable BIRC5 dependency in therapy-resistant TP53 mutated acute myeloid leukemia

TP53 mutations across multiple cancers, including acute myeloid leukemia (AML), are associated with poor outcomes irrespective of treatment modality. However, druggable vulnerabilities beyond canonical p53 targets remain largely unexplored. We identify BIRC5 (encodes survivin), an inhibitor of the apoptosis protein (IAP) family, as a novel vulnerability in TP53 mutant AML using an unbiased, comprehensive multiomics approach -- whole-genome CRISPR knockout screen, bulk and single-cell RNA-seq, proteomics, and high-throughput drug screen. Mechanistically, BIRC5 deletion in AML restored caspase-9 and -3/7 activity and downregulated other IAPs, implicating BIRC5 as the central post-mitochondrial regulator for blocking apoptosis. p53 stabilization suppressed BIRC5 selectively in TP53 wild-type AML, explaining BIRC5 upregulation in TP53 mutant lines and AML primary tumors (n > 700). Longitudinal single-cell RNAseq (n = 22 pairs) revealed expansion of BIRC5high stem and progenitor leukemia clones in TP53 mutant AML patients post-VenAza therapy. Survivin and IAP inhibitors emerged as top combination partners with VenAza in TP53 mutant AML cells and showed potent in vivo leukemic blast inhibition in cell line and patient-derived xenograft models along with primary tumors. Beyond AML, BIRC5 was upregulated broadly across 17 of 25 TP53 mutant cancers in the TCGA cohort, and combination with survivin inhibitors overcame chemotherapy resistance in TP53 deficient triple negative breast and colorectal cancers. These findings define BIRC5 as a critical, targetable dependency and unveil survivin/IAP inhibition as a promising therapeutic axis to overcome p53-related resistance across both hematologic and solid malignancies. Key PointsO_LIBIRC5 upregulation is a novel dependency in TP53 mutant AML that mediates therapy resistance by evasion of apoptosis. C_LIO_LICombination with Survivin/IAP inhibitors overcomes venetoclax/azacitidine resistance in TP53 mutant AML. C_LI

cancer biology↗

Quantitative proteomic mass spectrometry of protein kinases to determine dynamic heterogeneity of the human kinome

The kinome is a dynamic system of kinases regulating signaling networks in cells and dysfunction of protein kinases contributes to many diseases. Regulation of the protein expression of kinases alters cellular responses to environmental changes and perturbations. We configured a library of 672 proteotypic peptides to quantify >300 kinases in a single LC-MS experiment using ten micrograms protein from human tissues including biopsies. This enables absolute quantitation of kinase protein abundance at attomole-femtomole expression levels, requiring no kinase enrichment and less than ten micrograms of starting protein from flash-frozen and formalin fixed paraffin embedded tissues. Breast cancer biopsies, organoids, and cell lines were analyzed using the SureQuant method, demonstrating the heterogeneity of kinase protein expression across and within breast cancer clinical subtypes. Kinome quantitation was coupled with nanoscale phosphoproteomics, providing a feasible method for novel clinical diagnosis and understanding of patient kinome responses to treatment.

biochemistry↗

A near-complete genome assembly of the bearded dragon Pogona vitticeps provides insights into the origin of Pogona sex chromosomes

BackgroundThe agamid dragon lizard Pogona vitticeps is one of the most popular domesticated reptiles to be kept as pets worldwide. The capacity of breeding in captivity also makes it emerging as a model species for a range of scientific research, especially for the studies of sex chromosome origin and sex determination mechanisms. ResultsBy leveraging the CycloneSEQ and DNBSEQ sequencing technologies, we conducted whole genome and long-range sequencing for a captive-bred ZZ male to construct a chromosome-scale reference genome for P. vitticeps. The new reference genome is [~]1.8 Gb in length, with a contig N50 of 202.5 Mb and all contigs anchored onto 16 chromosomes. Genome annotation assisted by long-read RNA sequencing greatly expanded the P. vitticeps lncRNA catalog. With the chromosome-scale genome, we were able to characterize the whole Z sex chromosome for the first time. We found that over 80% of the Z chromosome remains as pseudo-autosomal region (PAR) where recombination is not suppressed. The sexually differentiated region (SDR) is small and occupied mostly by transposons, yet it aggregates genes involved in male development, such as AMH, AMHR2 and BMPR1A. Finally, by tracking the evolutionary origin and developmental expression of the SDR genes, we proposed a model for the origin of P. vitticeps sex chromosomes which considered the Z-linked AMH as the master sex-determining gene. ConclusionsOur study provides novel insights into the sex chromosome origin and sex determination of this model lizard. The near-complete P. vitticeps reference genome will also benefit future study of amniote evolution and may facilitate genome-assisted breeding.

genomics↗

Missense mutations in Myc Box I influence MYC cellular localization, mRNA partitioning and turnover to promote leukemogenesis

Somatic missense mutations in the phosphodegron domain of the MYC gene (MYC Box I) are detected in the dominant clones of a subset of acute myeloid leukemia (AML) patients, but the mechanisms by which they contribute to AML are unknown. To unveil unique proprieties of MBI MYC mutant proteins, we systematically compared the cellular and molecular consequences of expressing similar oncogenic levels of wild type and MBI mutant MYC. We found that MBI MYC mutants can accelerate leukemia by driving unique transcriptional signatures in highly selected, myeloid progenitor subpopulations. Although these mutations increase MYC stability, they overall dampen MYC chromatin localization and lead to a cytoplasmic accumulation of the mutant proteins. This phenotype is coupled with increased translation of RNA binding proteins and nuclear export machinery, which results in altered RNA partitioning and accelerated decay of select transcripts encoding proapoptotic and proinflammatory genes. Heterozygous knockin mice harboring the germline MBI mutation Myc p.T73N exhibit cytoplasmic MYC localization, myeloid progenitors expansion with similar transcriptional signatures to the overexpression model, and eventually develop hematological malignancies. This study uncovers that MBI MYC mutations alter MYC localization and disrupt mRNA subcellular distribution and turnover of select transcripts to accelerate tumor initiation and growth.

cancer biology↗

eQTLs identify regulatory networks and drivers of variation in the individual response to sepsis

Sepsis is a clinical syndrome of life-threatening organ dysfunction caused by a dysregulated response to infection, for which disease heterogeneity is a major obstacle to developing targeted treatments. We have previously identified gene expression-based patient subgroups (Sepsis Response Signatures: SRS) informative for outcome and underlying pathophysiology. Here we aimed to investigate the role of genetic variation in determining the host transcriptomic response and to delineate regulatory networks underlying SRS. Using genotyping and RNA-seq data on 638 adult sepsis patients, we report 16,049 independent expression (eQTLs) and 32 co-expression module (modQTLs) quantitative trait loci in this disease context. We identified significant interactions between SRS and genotype for 1,578 SNP-gene pairs, and combined transcription factor (TF) binding site information (SNP2TFBS) and predicted regulon activity (DoRothEA) to identify candidate upstream regulators. These included HIF1A and CEBPB, which were associated with progenitor and immature neutrophil subsets respectively, further implicating glycolysis and emergency granulopoiesis in SRS1. Overall, these approaches identified putative mechanistic links between host genetic variation, cell subtypes, and the individual transcriptomic response to infection. Understanding the regulatory networks underlying patient heterogeneity provides additional information for developing immunomodulatory treatments and a personalised medicine approach to treating sepsis.

genomics↗

Firing rate adaptation in continuous attractor neural networks accounts for theta phase shift of hippocampal place cells

Hippocampal place cells in freely moving rodents display both theta phase precession and procession, which is thought to play important roles in cognition, but the neural mechanism for producing theta phase shift remains largely unknown. Here we show that firing rate adaptation within a continuous attractor neural network causes the neural activity bump to oscillate around the external input, resembling theta sweeps of decoded position during locomotion. These forward and backward sweeps naturally account for theta phase precession and procession of individual neurons, respectively. By tuning the adaptation strength, our model explains the difference between "bimodal cells" showing interleaved phase precession and procession, and "unimodal cells" in which phase precession predominates. Our model also explains the constant cycling of theta sweeps along different arms in a T-maze environment, the speed modulation of place cells firing frequency, and the continued phase shift after transient silencing of the hippocampus. We hope that this study will aid an understanding of the neural mechanism supporting theta phase coding in the brain.

neuroscience↗

A Novel Gene REPTOR2 Activates the Autophagic Degradation of Wing Disc in pea aphid

Wing dimorphism is an evolutionarily adaptive trait to maximize insect fitness under various environments, by which the population could be balanced between migration and reproduction. Most studies concern the regulatory mechanisms underlying the stimulation of wing morph in aphids, but relatively little research addresses the molecular basis of wing loss. Here, we found that the wing disc of wingless-destined pea aphids degenerated 30 h post birth by autophagic rather than apoptotic degeneration, whereas winged-destined aphids developed normally. Activation of autophagy in 1st instar nymphs reduced the proportion of winged aphids, and suppression of autophagy increased the proportion. The REPTOR2 gene associated with TOR signaling pathway was identified by RNA-seq as a differentially expressed gene between the two morphs, with higher expression in the thorax of wingless-destined aphids. Further genetic analysis indicated that REPTOR2 could be a novel gene derived from a gene duplication event exclusively in pea aphid on autosome A1 but translocated to the sex chromosome. Knockdown of REPTOR2 reduced autophagy in the wing disc and increased the proportion of winged aphids. In agreement with REPTORs canonical negative regulatory role of TOR on autophagy, winged-destined aphids had higher TOR expression in the wing disc. Suppression of TOR activated autophagy of the wing disc and decreased the proportion of winged aphids, and vice versa. These results revealed that the TOR signaling pathway controlled degradation of the wing disc in pea aphids, and that REPTOR2 could modulate this autophagic degradation.

developmental biology↗

A transcriptional complex of FtMYB102 and FtbHLH4 coordinately regulates the accumulation of rutin in Fagopyrum tataricum

Tartary buckwheat is rich in flavonoids, which not only play an important role in plant-environment interaction, but are also beneficial to human health. Rutin is a therapeutic flavonol which is massively accumulated in Tartary buckwheat. It has been demonstrated that transcription factors control rutin biosynthesis. However, the transcriptional regulatory network of rutin is not fully clear. In this study, through transcriptome and target metabolomics, we validated the role of FtMYB102 and FtbHLH4 TFs at the different developmental stages of Tartary buckwheat. The elevated accumulation of rutin in the sprout appears to be closely associated with the expression of FtMYB102 and FtHLH4. Yeast two-hybrid, transient luciferase activity and co-immunoprecipitation demonstrated that FtMYB102 and FtbHLH4 can interact and form a transcriptional complex. Moreover, yeast one-hybrid showed that both FtMYB102 and FtbHLH4 directly bind to the promoter of chalcone isomerase (CHI), and they can coordinately induce CHI expression as shown by transient luciferase activity assay. Finally, we transferred the FtMYB102 and FtbHLH4 into the hairy roots of Tartary buckwheat and found that they both can promote the accumulation of rutin. Our results indicate that FtMYB102 and FtbHLH4 can form a transcriptional complex by inducing CHI expression to coordinately promote the accumulation of rutin.

plant biology↗

Myocardial ischemia-reperfusion injury is attenuated by sodium arsenite which inhibits NLRP3 inflammasome activation and induces a cellular stress response

Arsenite (NaAsO2) is a potent toxin that significantly contributes to human pathogenesis. Chronic exposure to arsenite results in various diseases. The physiologically important biological target(s) of arsenite exposure is largely unknown. Here we found that transient sodium arsenite treatment (1) blocks nigericin or Rotenone induced IL-1{beta} secretion; (2) inhibits mitochondrial respiration with complex I-linked substrate; (3) induces Heme oxygenase-1 (HO-1) in myocardial tissue. (4) attenuates the myocardial ischemia-reperfusion injury in an in vivo model of rats. The causal relationship among these activities needs further investigation.

pharmacology and toxicology↗

Genomic, Proteomic and Phenotypic Heterogeneity in HeLa Cells across Laboratories: Implications for Reproducibility of Research Results

The independent reproduction of research results is a cornerstone of experimental research, yet it is beset by numerous challenges, including the quality and veracity of reagents and materials. Much of life science research depends on life materials, including human tissue culture cells. In this study we aimed at determining the degree of variability in the molecular makeup and the ensuing phenotypic consequences in commonly used human tissue culture cells. We collected 14 stock HeLa aliquots from 13 different laboratories across the globe, cultured them in uniform conditions and profiled the genome-wide copy numbers, mRNAs, proteins and protein turnover rates via genomic techniques and SWATH mass spectrometry, respectively. We also phenotyped each cell line with respect to the ability of transfected Let7 mimics to modulate Salmonella infection.\n\nWe discovered significant heterogeneity between HeLa variants, especially between lines of the CCL2 and Kyoto variety. We also observed progressive divergence within a specific cell line over 50 successive passages. From the aggregate multi-omic datasets we quantified the response of the cells to genomic variability across the transcriptome and proteome. We discovered organelle-specific proteome remodeling and buffering of protein abundance by protein complex stoichiometry, mediated by the adaptation of protein turnover rates. By associating quantitative proteotype and phenotype measurements we identified protein patterns that explained the varying response of the different cell lines to Salmonella infection.\n\nAltogether the results indicate a striking degree of genomic variability, the rapid evolution of genomic variability in culture and its complex translation into distinctive expressed molecular and phenotypic patterns. The results have broad implications for the interpretation and reproducibility of research results obtained from HeLa cells and provide important basis for a general discussion of the value and requirements for communicating research results obtained from human tissue culture cells.

systems biology↗