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Qu, Z.

Publications and source records attributed to Qu, Z..

At least 37 records · Page 2Linked to original sources

Development of high-affinity, single-domain protein binders for neutralizing household allergens

Feline, canine, and human dust mite allergens drive significant IgE-mediated allergies in the household environment. Here, we describe the discovery and characterization of novel protein binders, termed AVA, which efficiently bind and disrupt major allergens from cats (Fel d 1), dogs (Can f 1, Can f 2), and dust mites (Der p 1, Der p 2). Leveraging camelid single-domain variable-heavy chain (VHH) antibodies, we identified and optimized VHH sequences with robust affinity towards the individual allergens. AVA disrupted critical allergen substructures (Fel d 1) and catalytic functions (Der p 1) in molecular dynamics simulations and in in vitro assays, respectively. Paired with robust thermostability and non-toxic in vitro viability profiles, AVA represents a promising approach for downstream household allergen mitigation.

bioengineering↗

Methadone blockade of IK1 promotes both long QT and Brugada-like arrhythmias: Mechanistic insights from computational modeling

BackgroundMethadone is widely used for chronic pain relief and in the maintenance therapy of opioid use disorder, however, it also increases the risk of ventricular arrhythmias and sudden cardiac death. Methadone blocks several ionic currents with different half-maximal inhibitory concentrations (IC50), including the rapid component of the delayed rectifier potassium current (IKr), the inward rectifier potassium current (IK1), the L-type calcium current (ICa,L), and the late component of the sodium current (INaL). Despite the well-known proarrhythmic effect of IKr blockade, the effects of blocking other ionic currents on arrhythmogenesis remain less well understood. MethodsComputer simulations were used to explore the proarrhythmic effects of methadone by investigating how its blocking effects on ionic currents act alone or together in arrhythmogenesis. ResultsThe major findings are: 1) blocking IK1 potentiates QT prolongation-related arrhythmogenesis by enhancing a tissue-scale dynamical instability for the spontaneous genesis of ectopic excitations. Blocking IK1 and IKr together results in a synergistic effect, greatly increasing the arrhythmia propensity, much larger than that of blocking either one alone; 2) blocking IK1 in combination with lowering ICa,L potentiates phase-2 reentry caused by spike-and-dome action potential morphology, an arrhythmia mechanism of Brugada syndrome. Blocking IKr exhibits little effect for this mechanism of arrhythmias; and 3) hypoxia, often comorbid in methadone populations, can potentiate QT prolongation-related arrhythmias at high sympathetic activity and phase-2 reentry at low or basal sympathetic activity, mainly via its effect on ICa,L. ConclusionsThese simulation results provide mechanistic insights into the genesis of QT prolongation-related Torsades de Pointes and Brugada-like ECG related arrhythmias caused by methadone use.

pharmacology and toxicology↗

Ethylene modulates cell wall mechanics for root responses to compaction

Soil stresses impact crop yields, presenting global agricultural challenges. Soil compaction triggers root length reduction and radial expansion driven by the plant hormone ethylene. We report how ethylene controls cell wall properties to promote root radial expansion. We demonstrate how soil compaction stress, via ethylene, upregulates Auxin Response Factor1 in the root cortex, which represses Cellulose Synthase (CESA) genes. CESA repression drives radial expansion of root cortical cells by modifying the thickness and mechanics of their cell walls, which result in a "stiff epidermis-soft cortex" contrast. Our research thus connects ethylene signaling with root mechanics via cell wall strength, and reveals how dynamic regulation of cellulose synthesis crucially controls root growth in compacted soil.

plant biology↗

Axially decoupled photo-stimulation and two photon readout (ADePT) for mapping functional connectivity of neural circuits

All-optical in vivo physiology enables three-dimensional interrogation of neural circuits function. Here, we introduce ADePT (Axially-Decoupled Photo-stimulation and Two-photon readout), a strategy that combines flexible optogenetic stimulation with neural activity imaging. ADePT achieves axially contained widefield patterned stimulation by coupling a digital micro-mirror device illuminated by a solid-state laser to a motorized holographic diffuser, while in parallel performing multiphoton imaging across different z-planes. As a proof of principle, we apply ADePT to map excitatory and inhibitory functional connectivity in the mouse early olfactory system. By controlling activity in individual glomeruli on the olfactory bulb surface and recording responses from output mitral and tufted cells in deeper layers, we identify cohorts of sister cells driven by the same parent glomerulus and analyze their distinct connectivity patterns. We further report specificity in the inhibitory circuitry, as we find that GABAergic/dopaminergic (DAT+) interneurons associated with different glomeruli selectively suppress baseline and odor-evoked activity in distinct mitral and tufted cell populations. Together, these results establish ADePT as a platform for high-throughput functional connectivity mapping in optically accessible brain regions.

neuroscience↗

ZUGC-RNA degradation generates immunosuppressor to evade immune responses in eukaryotes

Among the hundreds of modified nucleosides identified in terrestrial life, 2-amino-6-aminopurine (Z) is widely recognized as a prominent modified purine. Recently, RNA written with the ZUGC alphabet shows significant potential in RNA therapeutics as a synthetic biosystem. Here, we demonstrate that ZUGC-RNA can evade immune recognition in eukaryotes, independent of factors such as RNA length, sequence, 5-triphosphate, modified uridine, and secondary structure. Notably, we discovered that both the degradation of ZUGC-RNA and metabolites of Z-nucleotides can function as immunosuppressors, silencing TLR7 sensing to block immune responses. This mechanism differs from that of pseudo-uridine ({Psi}) modified RNA currently in use. ZUGC-RNAs also demonstrate broad applicability across multiple neural cell types. Our findings provide valuable insights for developing more tolerable RNA-based drugs and designing immunomodulators targeting TLR7. In addition to the potential prebiotic relevance of Z, our finding not only contributes to understanding the RNA world hypothesis but also provides new insights into the exploration of the origin of life.

synthetic biology↗

Discovery of Chirally-dependent Protein O-2-Hydroxyglutarylation by D2HG and L2HG

Mutations in isocitrate dehydrogenase 1 (IDH1) and IDH2 are common in multiple types of human cancer, leading to the accumulation of D-2-hydroxyglutarate (D2HG) and the promotion of tumorigenesis1. Here we discovered a novel O-2- hydroxyglutarylation by D2HG using chemical proteomics and further revealed distinct chiral preferences for D/L2HG modifications. Notably, we identified two kinases, MRCKA and SLK, modified by D2HG and L2HG respectively, and detected reduced phosphorylation of their substrates, suggesting an inhibitory effect of D/L 2HG modifications on the kinases activity.

biochemistry↗

NaDyNet: A Toolbox for Dynamic Network Analysis of Naturalistic Stimuli

Experiments with naturalistic stimuli (e.g., listening to stories or watching movies) are emerging paradigms in brain function research. The content of naturalistic stimuli is rich and continuous. The fMRI signals of naturalistic stimuli are complex and include different components. A major challenge is isolate the stimuli-induced signals while simultaneously tracking the brains responses to these stimuli in real-time. To this end, we have developed a user-friendly graphical interface toolbox called NaDyNet (Naturalistic Dynamic Network Toolbox), which integrates existing dynamic brain network analysis methods and their enhanced versions. The main features of NaDyNet are: 1) extracting signals of interest from naturalistic fMRI signals; 2) incorporating six commonly used dynamic analysis methods and three static analysis methods; 3) enhanced versions of these dynamic methods by adopting inter-subject analysis to eliminate the effects of non-interest signals; 4) performing K-means clustering analysis to identify temporally reoccurring states along with their temporal and spatial attributes. We then introduced the rationale for incorporating inter-subject analysis to improve existing dynamic brain network analysis methods, and presented numerous examples. We also summarized research progress in comparing methodological efficacy, offered our recommendations for method selection in dynamic network analysis, and discussed the limitations of current approaches and directions for future research. We hope that this open source toolbox will promote the development of naturalistic neuroscience. The toolbox is available at https://github.com/yuanbinke/Naturalistic-Dynamic-Network-Toolbox.

neuroscience↗

The aberrant language network dynamics in autism ages 5-40 years

Language impairments across both structural components and pragmatic use are frequently observed in individuals with autism spectrum disorder (ASD). These difficulties are thought to stem from atypical brain development and abnormal network interactions, yet an integrative network-level model accounting for such impairments remains lacking. To bridge this gap, we applied the dynamic meta-networking framework of language, a theoretical model capturing domain-segregation dynamics during rest, to examine age-related changes (5-60 years) in cortical language networks in individuals with ASD. To further probe the biological underpinnings of these dynamics, we quantified spatial correspondences between network state hubs and gene co-expression modules as well as neurotransmitter receptor distributions. We identified distinct language meta-states characterized by domain-segregation connectivity patterns, which exhibited spatial alignment with gene co-expression modules and neurotransmitter systems. Individuals with ASD showed state-dependent developmental trajectories marked by age-related hypo- and hyper-connectivity. Critically, these network alterations strongly predicted verbal IQ and communicative difficulties, but were unrelated to social functioning or stereotyped behaviors. Our findings provide novel evidence that language-related network dynamics in ASD are developmentally altered, biologically grounded, and selectively linked to verbal and communicative impairments. These results advance a network-level model of language dysfunction in ASD and highlight potential mechanistic pathways for targeted interventions. Lay SummaryLanguage challenges are common in autism and can affect both learning language and using it in everyday conversations. In people aged 5-60, we found distinct, age-changing patterns in how the brains language areas connect at rest; these patterns align with basic biology (genes and brain chemicals) and strongly relate to verbal ability and daily communication, but not to social difficulties or repetitive behaviors. These results suggest clear, brain-based targets for earlier and more tailored support for language problems in autism.

neuroscience↗

Correlative Imaging for Comprehensive Molecular Mapping of Individual Cell Types in Biological Tissues

Mass spectrometry imaging (MSI) is a powerful technique for label-free spatial mapping of multiple classes of biomolecules in tissue sections. However, differences in desorption and ionization efficiency of different classes of molecules make it challenging to simultaneously map biomolecules at each omics layer in the same tissue sample. Herein, we present a correlative imaging method using nanospray desorption electrospray ionization (nano-DESI) MSI, which enables the spatial mapping of lipids, metabolites, peptides, and proteins with cellular-level spatial resolution in a single tissue section. We demonstrate the molecular profiling of specific cell types and identify truncated peptides in mouse pancreatic tissue. Distinct chemical gradients of peptides and lipids extending from endocrine cells to exocrine cells indicate their different roles in endocrine-exocrine crosstalk and intracellular signaling. The results underscore the power of the developed imaging approach for spatial multi-omics analysis that provides deep insights into cellular diversity and the intricate molecular interactions that occur within heterogenous biological tissues.

biochemistry↗

The connectional diaschisis and normalization of cortical language network dynamics after basal ganglia and thalamus stroke

Stroke affecting the basal ganglia and thalamus can lead to language deficits. In addition to the lesions direct impact on language processing, connectional diaschisis involving cortical-subcortical interactions also plays a critical role. This study investigated connectional diaschisis using the "dynamic meta-networking framework of language" in patients with basal ganglia and thalamus stroke, analyzing longitudinal resting-state fMRI data collected at 2 weeks (n = 32), 3 months (n = 19), and one year post-stroke (n = 23). As expected, we observed dynamic cortico-subcortical interactions between cortical language regions and subcortical regions in healthy controls (HC, n = 25). The cortical language network exhibited dynamic domain-segregation patterns in HCs, severely disrupted in the acute phase following stroke. The connectional diaschisis manifested as dual effects characterized by both hypo- and hyper-connectivity, which positively and negatively correlated with language deficits, respectively. State-specific changes in nodal and topological properties were also identified. Throughout language recovery, cortical language network dynamics gradually normalized toward sub-optimal domain-segregation patterns, accompanied by the normalization of nodal and topological properties. These findings underscore the crucial role of cortico-subcortical interactions in language processing.

neuroscience↗

How do we imagine a speech? A triple network model for situationally simulated inner speech

Inner speech is a silent verbal experience and plays central roles in human consciousness and cognition. Despite impressive studies over the past decades, the neural mechanisms of inner speech remain largely unknown. In this study, we adopted an ecological paradigm called situationally simulated inner speech. Unlike mere imaging speech of words, situationally simulated inner speech involves the dynamic integration of contextual background, episodic and semantic memories, and external events into a coherent structure. We conducted dynamic activation and network analyses on fMRI data, where participants were instructed to engage in inner speech prompted by cue words across 10 different contextual backgrounds. Our seed-based co-activation pattern analyses revealed dynamic involvement of the language network, sensorimotor network, and default mode network in situationally simulated inner speech. Additionally, frame-wise dynamic conditional correlation analysis uncovered four temporal-reoccurring states with distinct functional connectivity patterns among these networks. We proposed a triple network model for deliberate inner speech, including language network for a truncated form of overt speech, sensorimotor network for perceptual simulation and monitoring, and default model network for integration and sense-making processing. HighlightsO_LIIn ten contextual backgrounds, subjects were instructed to perform situationally simulated inner speech based on cue words. C_LIO_LIThe ventral parts of the bilateral somatosensory areas and middle superior temporal gyrus were as centers for seed-based co-activation pattern analyses. C_LIO_LIA triple network model of language network, sensorimotor network, and default mode network was proposed for deliberate inner speech. C_LI

neuroscience↗

A systematic evaluation of dynamic functional connectivity methods using simulation data

Numerous dynamic functional connectivity (dFC) methods have been proposed to study time-resolved network reorganization in rest and task fMRI. However, a comprehensive comparison of their performance is lacking. In this study, we compared the efficacy of seven dFC methods (and their enhanced versions) to track transient network reconfiguration using simulation data. The seven methods include flexible least squares (FLS), dynamic conditional correlation (DCC), general linear Kalman filter (GLKF), multiplication of temporal derivatives (MTD), sliding-window functional connectivity with L1-regularization (SWFC), hidden Markov models (HMM), and hidden semi-Markov models (HSMM). Multiple datasets of non-fMRI-BOLD and fMRI-BOLD signals with predefined covariance structures, signal-to-noise ratio levels, and sojourn time distributions were simulated. We adopted inter-subject analysis to eliminate the effects of signals of non-interest, resulting in enhanced methods: ISSWFC, ISMTD, ISDCC, ISFLS, ISKF, ISHMM, and ISHSMM. Efficacy was defined as the spatiotemporal association between simulated and estimated data. We found that all enhanced dFC methods outperformed their original versions. Efficacies depend on several factors, such as considering the neurovascular effect in simulated data, the covariance structure between two time series, state sojourn distribution, and signal-to-noise ratio levels. These results highlight the importance of selecting appropriate dFC methods in fMRI study.

neuroscience↗

Insect metamorphosis is regulated differently between sexes by members of a microRNA cluster

Insects comprise the majority of all described animal species and dominate the terrestrial habitats. The evolution of insect metamorphosis played a profound role in their successful adaptation and radiation. Insect metamorphosis is dependent on hormones ecdysteroids and sesquiterpenoids such as juvenile hormone. Despite the fact there are genuine differences between sexes during insect metamorphosis which facilitate their successful mating, how such sexual dimorphism in metamorphosis is being controlled is poorly known. We first generated transcriptomic profiles of male and female flies in late larvae and early pupae stages. Using a combination of genome-wide prediction and in vitro dual-luciferase validations, members of a microRNA cluster miR-277/34 were found to potentially regulate the neuropeptide receptor (AstC-R1) that when activated inhibits the sesquiterpenoid pathway and a juvenile hormone-dependent transcription factor (Kr-h1) in fly Drosophila melanogaster. Loss-of-function mutants were created deleting either miR-277 or miR-34, and expression levels of both AstC-R1 and Kr-h1 as well as ecdysteroid and sesquiterpenoid hormone titres were altered. Further comparison of transcriptomes of the late larvae and early pupae of both sexes revealed differential gene pathways being regulated by members of miR-277/34 between sexes during metamorphosis. This study highlights how members of a microRNA cluster control hormonal and developmental gene pathways in different sexes of insects during metamorphosis.

evolutionary biology↗

Validating the Target Functions and Synergistic Multi-Target, Multi-Pathway Action Mode of Compound Kushen Injection Using CRISPR/CAS

Background and PurposeDue to the complexity of traditional Chinese medicine based on complex mixtures of natural products and their multi-target mechanism of action, the discovery and validation of relevant targets have always been challenging. In previous studies, using transcriptomic methods and Compound Kushen Injection (CKI) as a model drug, we identified multiple pathways and target genes through which CKI exerts its pharmacological effects. Therefore, we wished to verify these targets by perturbing those genetic pathways. Experimental ApproachIn this study, we selected eight key genes from four candidate pathways and used CRISPR/CAS technology to knock out these genes in four cell lines, validating their role in CKI activity. Key ResultsFirstly, we found that although the sensitivity of different cell lines to gene knockout varied, overall, it led to a reduction in various cellular activities. After the addition of CKI, we observed that, except for the minor impact of CDKN1A gene knockout on the effect of CKI, knocking out the other genes significantly affected the pharmacological efficacy of CKI in different assays. Among them, knockout of MYD88 and NFkB genes enhanced the efficacy of CKI. At the same time, we found that the genes IL24 and CYP1B1 play a crucial role in CKI inhibition of tumour cell migration, and the CYP1A1 gene is critical for the cell cycle arrest induced by CKI. Conclusion and ImplicationsThese findings not only validate the results of our previous transcriptomic analysis but also further demonstrate the complexity of pharmacological mechanisms of multi-target synergistic action of natural product mixtures. What is already knownCKI demonstrates antitumor effects in both clinical and pharmacological research. Transcriptomic analysis shows CKI can perturb the expression of numerous genes in pathways related to cancer. What does this study addThe knockout of most selected genes whose expression is altered by CKI can significantly affect the pharmacological effects of CKI. IL24 and CYP1B1genes are essential to CKIs inhibition of cancer cell migration and CYP1A1 is important for CKIs G2M cell cycle arrest effect. What is the clinical significanceThe efficacy of CKI is demonstrated to arise from the synergistic action of multiple pathways and targets.

pharmacology and toxicology↗

Response of protein coding genes and microRNAs to temperature changes in four insect species

Insects are the most abundant described living creatures in the world, and they play important roles in our global ecosystem. Climate change affects global biodiversity, and researchers in many fields are striving to better understand the impact of the climate crisis. One such endeavour is the study of temperature-dependent effects on insects. At present, we know little of how climate affects gene expression in insects of different sexes. Here, we took four species of fruit flies of the genus Drosophila (D. melanogaster, D. virilis, D. pseudoobscura, and D. erecta), and subjected the male and female flies of each species to three different temperatures to test their sex-specific gene expression responses. A total of 144 transcriptomic profiles of protein-coding genes and microRNAs were generated. We found that, at the same temperature, there were more male-biased than female-biased protein-coding genes and microRNAs in all four investigated drosophilid species. Interestingly, upon temperature changes, there were more differentially expressed protein-coding genes in females than in males in all four investigated species, while the microRNAs were highly species- and sex-specific. This study provides the first evidence that sex-biased protein-coding gene and microRNA expression responses to temperature change differ between insect species within the same genus, and demonstrates the complexity of sex-specific responses of insects to climate change. HighlightsO_LIAt the same temperature, protein coding gene and microRNA expression showed a greater bias towards males than towards females in all four tested insect species. C_LIO_LIIn response to increasing temperature, females of all 4 tested species exhibited more differentially expressed genes than did males, and enrichment analyses showed that they are species-specific. C_LIO_LIDifferentially expressed microRNAs did not show a conserved trend between insects upon temperature changes. C_LIO_LISex-specific gene and microRNA expression of insects in response to climate change evidently involves a complex adaptation mechanism. C_LI Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=121 SRC="FIGDIR/small/591511v1_ufig1.gif" ALT="Figure 1"> View larger version (27K): org.highwire.dtl.DTLVardef@1037b18org.highwire.dtl.DTLVardef@18683f3org.highwire.dtl.DTLVardef@40dee5org.highwire.dtl.DTLVardef@e9a108_HPS_FORMAT_FIGEXP M_FIG C_FIG

molecular biology↗

AMHY and sex determination in egg-laying mammals

The sex chromosomes of egg-laying mammals (monotremes), which lack the sex determining gene SRY1, evolved independently to those of all therian mammals2,3. Here we characterise the candidate monotreme sex determining gene, the Y-localised anti-Mullerian hormone gene (AMHY)4,3 and trace its expression during the period of sexual differentiation. Monotreme AMHX and AMHY gametologues have significant sequence divergence at the promoter, gene and protein level, likely following an original allele inversion in the common monotreme ancestor but retain conserved features of TGF-{beta} molecules. Expression of sexual differentiation genes in the echidna fetal gonad were significantly different from that of therian mammals. AMHY expression was seen exclusively in the male gonad during sexual differentiation, whereas AMHX was expressed in both sexes. Experimental ectopic expression of platypus AMHX or AMHY in the chicken embryo did not masculinise the female urogenital system, a possible result of mammalian specific changes to AMH proteins preventing function in the chicken. Our results provide fundamental insight into the first steps of monotreme sex chromosome evolution and sex determination with developmental expression data strongly supporting AMHY as the primary male sex determination gene.

evolutionary biology↗

Pseudogenisation of NK3 Homeobox 2 (Nkx3.2) in Monotremes Provides Insight into Unique Gastric Anatomy and Physiology

Development of the vertebrate antral stomach and pyloric sphincter (antropyloric region) - involved in enzymatic breakdown and thoroughfare of food - is underpinned by a highly conserved developmental pathway involving the hedgehog, bone morphogenetic protein (BMP) and Wingless/Int-1 (Wnt) protein families. Monotremes are a unique lineage where acid-based digestion has been lost, and this correlates with a lack of genes for gastric acid and enzymes in the genomes of the platypus (Ornithorhynchus anatinus) and short-beaked echidna (Tachyglossus aculeatus). Furthermore, these species feature unique gastric phenotypes, both with truncated and aglandular antral stomachs and the platypus with no pylorus. Here, we explore the genetic underpinning of monotreme gastric phenotypes, investigating genes important in antropyloric development using the newest monotreme genome sequences (mOrnAna1.pri.v4 and mTacAcu1) together with RNA-seq data. We found that the pathway is generally conserved but, NK3 homeobox 2 (Nkx3.2) was pseudogenised in both platypus and echidna. We speculate that pyloric-like restriction in the echidna may correlate with independent evolution of Grem1 and Bmp4 sequences, and that the convergent loss of gastric acid and stomach size genotypes and phenotypes in teleost and monotreme lineages may be a result of eco-evolutionary dynamics. These findings reflect the effects of gene loss on phenotypic evolution and further elucidate the genetic control of monotreme stomach anatomy and physiology.

evolutionary biology↗

Gain of function in linc-133 compensates for daf-18/PTEN loss and rescues survival

DAF-18, homology of PTEN, possess tumor suppressor activity. Loss of daf-18 causes cell growth in L1 diapause C. elegans is well studied; however, the reason why survival is dramatically shortened is not well elaborated. We found that linc-133 gain of function can fully restore the shortened survival caused by daf-18 loss. When lipid phosphatase activity of DAF-18 is defective, the linc-133 gain of function interacts with 14-3-3 proteins to obstruct DAF-16 translocation from the nucleus to the cytoplasm. However, the dysfunction of protein phosphatase activity of DAF-18 caused high levels of aggregated proteins. The linc-133 gain of function can induce HSP chaperones to select and process the aggregated proteins for degradation through ubiquitination. Our work demonstrates that protein homeostasis controlled by the protein phosphatase activity of DAF-18 is the main factor affecting survival and identifies a new function of the linc-133 gene, which can compensate for the loss of daf-18.

genetics↗