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wang, y.

Publications and source records attributed to wang, y..

At least 19 recordsLinked to original sources

Transcriptome-Inspired Spiking Simulations Uncover Human-Specific Prefrontal Dynamics and Provide a Mechanistic Platform for Species-Appropriate Disease Modeling.

Whole-brain transcriptomic atlases are now widely available, yet computational neural models are almost exclusively parameterized from rodent data and used to infer human brain function, an extrapolation whose cost remains unquantified. To address this, we constructed a biophysically detailed, conductance-based Hodgkin-Huxley spiking microcircuit of a five-population prefrontal network, where every ion-channel, receptor, and gap-junction conductance was scaled by cell-type-specific gene expression. We parameterized the identical circuit using single-nucleus RNA-seq from mouse mPFC and human DLPFC, alongside a literature-derived baseline, and compared their high-frequency-oscillation (HFO) outputs across seven physiological and pathological states. While population firing rates differed only modestly between the two refinements ([~]20% for pyramidal and PV cells), the oscillatory dynamics diverged dramatically. The human-refined circuit generated strongly synchronized PV activity and robust ripple- and fast-ripple-band power (e.g., healthy-wake ripple power, in arbitrary units: 322 vs. 24 and 22), whereas the mouse-refined and literature arms remained asynchronous (interneuron synchrony: 0.21 vs. 0.02). This human >>mouse {approx} original hierarchy was statistically consistent across all seven states (significant arm differences in 75/77 comparisons). Mechanistically, the human transcriptome drove markedly stronger PV-PV electrical coupling (gap-junction scale: 1.78 vs. 0.96) paired with stronger recurrent pyramidal excitation, which collectively synchronized the fast-spiking PV population into a coherent rhythm that perisomatic inhibition then imposed on the local field potential. Critically, these results are model-dependent; the gene-to-conductance mapping is phenomenological, and mRNA expression does not linearly translate to functional conductance. Nonetheless, under this mapping the divergence localizes PV-mediated coupling and excitation-inhibition balance as the parameters most in need of human-specific recalibration. More broadly, this work establishes transcriptome-informed spiking simulation as a powerful strategy for uncovering species-specific computational principles and for building mechanistically grounded, human-relevant models of prefrontal circuit dysfunction, an approach that moves beyond generic rodent defaults to enable targeted, species-appropriate modeling of neurological and psychiatric disorders.

neuroscience↗

Microglia-derived IL-18 remodels hippocampal plasticity to constrain traumatic fear memory

Post-traumatic stress disorder (PTSD) involves complex neuroimmune-synaptic crosstalk in the hippocampus. Here we show that interleukin-18 (IL-18), an extensively studied pro-inflammatory cytokine, serves a protective role against traumatic fear memory through a microglia-to-neuron signaling axis. Traumatic stress induces sustained upregulation of IL-18 in the hippocampus. Exogenous IL-18 administration attenuates fear memory, whereas blockade of IL-18 signaling exacerbates it. Mechanistically, microglial-derived IL-18 acts on neuronal IL-18R1 to restore stress-impaired synaptic plasticity and reduce perineuronal net density, thereby facilitating structural synaptic remodeling. In addition, IL-18 modulates the synaptic organization of fear memory-encoding engram cells within hippocampal ensembles. Together, these findings redefine IL-18 as a homeostatic regulator of post-trauma hippocampal synaptic function and identify the hippocampal IL-18 pathway as a potential therapeutic target for PTSD.

neuroscience↗

SERPINA3 and NDRG1 are critical diagnostic immune genes associated with macrophages in preeclampsia

ObjectiveThe immune system plays a role in the occurrence and progression of numerous pregnancy complications, particularly preeclampsia (PE). This study aims to identify critical immune biomarkers via machine learning and assess their predictive ability. MethodsGene expression data were retrieved from the GEO database, while immune-related genes were obtained from the ImmPort repository. Differential expression analysis was then conducted to identify immune genes associated with PE. Different immune-related genes (DIRGs) were subjected to functional and pathway enrichment analysis. We adopted protein-protein interaction (PPI) networks for exploring the connections among various DIRGs and integrated two machine-learning to pinpoint candidate biomarkers in PE. Diagnostic performance was assessed via ROC curve analysis, with predictive accuracy further quantified using nomogram calibration. Findings were validated through integrated computational and experimental analyses. In silico validation utilized additional GEO datasets, while experimental confirmation involved qRT-PCR and IHC assessment of placental tissues. We developed a nomogram to predict PE utilizing two immune-related genes. Cellular composition was inferred from transcriptomic data using CIBERSORT deconvolution.. ResultsWe identified 66 differentially expressed genes (DEGs) and 10 DIRGs between PE pregnancies and normotensive pregnancies. The GO analyses revealed that the DIRGs were enriched in gonadotropin secretion, the regulation of gonadotropin secretion, and the regulation of endocrine processes. Functional annotation revealed enrichment in cytokine and neuroactive ligand-receptor pathways. SERPINA3 and NDRG1 emerged as top-performing biomarkers (training AUCs: 0.812 and 0.866; external validation: 0.795 and 0.781), with overexpression validated in clinical specimens. Both genes inversely regulated M2 macrophage abundance (P < 0.05). ConclusionPE is fundamentally an immune-mediated disorder. SERPINA3 and NDRG1 can be identified as key immune genes associated with M2 macrophages, and these findings provide novel perspectives for the diagnosis and pathogenesis of PE.

immunology↗

Refining liquid chromatography conditions across platforms to democratize single-cell proteomics

Single-cell proteomics has emerged as a powerful approach for characterizing cellular heterogeneity. Here, we present an optimized scProteomic workflow that enhances proteome coverage and quantification by refining liquid chromatography (LC) conditions across platforms (both Evosep and nanoElute2). Importantly, our results show that using our optimized LC conditions, even with Bruker timsTOF HT, a machine not designed for scProteomics applications, we achieved solid performance with single cell samples that allows meaningful biological discoveries. First, we compared power to detect differentially-expressed genes/proteins between scRNA-seq and scProteomics at single cell level, and demonstrated that scProteomics showed an excellent performance at small sample sizes. To further validate this finding, we applied our optimized workflow to study the proteomic response to oxidative stress using a limited number of single cells. Our scProteomics results successfully detected 3 distinct cell populations, reflecting correctly the 3 cell lines used, and captured the dysregulation of antioxidant enzymes, molecular chaperones and ubiquitin-proteasome system, reflecting a multi-faceted response to oxidative stress that is uniform across distinct cell lines. Our results highlighted the potential of scProteomics to resolve subtle perturbations and provide a readout of cellular states for the broader community, including users operating non-scProteomics-dedicated machines.

systems biology↗

Oncometabolite fumarate impairs ATR-CHK1 signaling by succinating RPA1 in Fumarate Hydratase-deficient renal cell carcinoma cells

Abnormal accumulation of oncometabolite fumarate drives susceptibility in fumarate hydratase-deficient renal cell carcinoma (FH-dRCC), but the precise mechanisms remain not fully understood. In this study, we demonstrate that high fumarate levels impair activation of ATR-CHK1 signaling in response to replication stress and DNA damage. Mechanistically, fumarate modifies RPA1, an essential factor for ATR-CHK1 activation through succination, a post-translational modification. Succination of RPA1 occurs mainly at cysteine residues 481 and 486, which reduces its binding affinity for single-stranded DNA (ssDNA). RPA1 succination leads to deficient recruitment of TOPBP1 to ssDNA, resulting in attenuated CHK1 activation and defective cell cycle arrest in response to DNA damage. Succinated RPA1 compromises homologous recombination-mediated DNA repair. Our findings establish that fumarate-induced succination of RPA1 impairs DNA repair and cell cycle control, promoting genomic instability in FH-dRCC. This work reveals a novel mechanism by which oncometabolites contribute to genomic instability.

cancer biology↗

TET2 loss impairs MPLA-induced innate immune memory during infection and disrupts hematopoiesis via RIPK1 in mice

Ten-eleven translocation protein 2 (TET2) is commonly mutated in hematologic disorders of bone marrow failure such as myelodysplastic syndrome (MDS), and loss of TET2 is associated with poor prognosis. TET2 loss is also associated with augmented inflammation, as well as impaired innate immune responses. However, many individuals harboring mutations do not develop hematologic disorders, indicating that additional factors, such as inflammation, cooperate with TET2 loss to promote disease progression. Innate immune memory is a phenomenon in which pre-treatment with microbial ligands, including monophosphoryl lipid A (MPLA), improves innate immune function while minimizing inflammation during subsequent infection. Given the previously reported innate immune impairments attributed to TET2 loss, we tested whether MPLA could induce an innate immune response in TET2-deficient mice infected with P. aeruginosa. Moreover, due to the inflammatory role of TET2 loss, we investigated whether MPLA with infection would promote disease-related phenotypes. We found that TET2-deficient mice display impaired infection response to P. aeruginosa which is partially improved with MPLA pretreatment. Assessments of pathogenic clearance functions further showed decreased capacity in TET2-deficient innate immune cells. Moreover, TET2-defcient cells also exhibit impaired differentiation. MPLA pretreatment in infected mice promotes myeloid-biased hematopoiesis at the expense of erythroid- and megakaryocyte-biased hematopoiesis, resembling MDS-like disease progression. Intriguingly, inhibition of receptor-interacting serine/threonine-protein kinase 1 (RIPK1) dampens the effects of TET2 loss on hematopoietic perturbation. Collectively, we find that TET2 loss impairs innate immune memory and infection responses, and MPLA with infection promotes hematopoietic skewing through RIPK1. KEY POINTS- TET2 loss increases susceptibility to infection, but immune response can be improved by MPLA-induced innate immune memory. - MPLA pretreatment and infection promotes aberrant hematopoiesis and myeloid bias in TET2 deficiency that is improved by RIPK1 inhibition.

cancer biology↗

16S rRNA Survey Reveals the Potential of Oral Microbiota in Distinguishing Patients with Chronic Heart Failure from Healthy Controls

BackgroundOral microbiota can reflect physiological functions and pathological conditions in human body. Patients with chronic heart failure (CHF) exhibit distinct oral health status compared to healthy controls (HCs), which is attributed to the differences in dominant microbial communities present in the oral cavity. Up to date, there are few studies examined the association between CHF and dominant oral microbiota. To fill in this research gap, this study aimed to investigate the differences of oral microbiota between CHF patients and HCs, to identify valuable novel biomarkers for CHF. MethodsChronic heart failure patients and healthy volunteers were recruited. Oral microbiota samples were then collected using oral swabs, and 16S rRNA sequencing was employed to analyze the microbiota. Statistical analysis was conducted to identify key bacteria at multiple taxonomic levels in the oral microbiota samples from both the CHF patient and healthy control groups, with a focus on core genera to identify potential biomarkers and evaluate their diagnostic efficacy. ResultsThere were 60 CHF patients and 30 HCs were recruited, with 42 CHF patients with New York Heart Association (NYHA) functional class II-IV and 28 HCs were included in the final analysis. The alpha diversity was higher in HCs, while beta diversity was higher in CHF patients. The CHF patients showed significant differences from HCs at five gene (phylum, class, order, family and genus) levels by analyzing the relative richness of microbiota at different taxomal levels. Altogether 14 microbes could distinguish CHF patients from HCs, i.e., Abiotrophia, Butyrivibrio, Lactobacillus, Capnocytophaga and Neisseria which are more abundant in CHF patients, and Actinomyces, Anaerovorax, Eubacterium, Kingella, Mogibacterium, Peptococcus, Peptostreptococcus, Solobacterium and TM7_genus_incertae_sedis which are more abundant in HCs. Furthermore, the AUC of their combined diagnosis was 83.7% (95% confidential interval 74.1%-93.3%), which have high reliability for the diagnostic significance. In accordance to Spearmans correlation, Eubacterium, Solobacterium and Rhizobium were core genera and the abundance of Eubacterium and Solobacterium exhibited downward trends as NYHA class increases. ConclusionThis study revealed the dysbiosis of the oral microbiota in CHF patients and identified potential biomarkers for CHF diagnosis and management. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=113 SRC="FIGDIR/small/669863v1_ufig1.gif" ALT="Figure 1"> View larger version (26K): org.highwire.dtl.DTLVardef@d60f6eorg.highwire.dtl.DTLVardef@18f17ceorg.highwire.dtl.DTLVardef@163f0daorg.highwire.dtl.DTLVardef@599bcd_HPS_FORMAT_FIGEXP M_FIG C_FIG

microbiology↗

SURFS and AlphaFold Reveal Ribosome Footprint Shift Caused by EF-Tu D81 Mutation

Protein synthesis relies on accurate mRNA decoding by tRNA, a process guided by EF-Tu. We investigated how mutations at a conserved residue, aspartate 81, affect EF-Tu function using GTPase assays, AlphaFold modeling, and quantum-sensing-based super-resolution force spectroscopy (SURFS). All D81 variants retained GTPase activity but impaired tRNA release, revealed by sub-nucleotide ribosome footprinting. AlphaFold3 modeling suggests that D81 mutations disrupt magnesium coordination and interaction with the sarcin-ricin loop in the GTP-bound state. AlphaFold2-based sequence-structure analysis indicates that D81 anchors coevolutionary constraints, and its mutation enables cryptic structural variation. These results show how a single conserved residue links catalytic coordination, allosteric communication, and evolutionary constraint, offering mechanistic insight into translation fidelity and demonstrating the utility of an unconventional force spectroscopy in probing ribosome dynamics.

biophysics↗

TRiC-assisted folding of class I HDAC family proteins regulated by distinct co-chaperone and cofactor networks

Class I histone deacetylases (HDACs), including HDAC1, HDAC2, HDAC3, and HDAC8, are essential for diverse cellular processes. Although the chaperonin TRiC is implicated in the activation of class I HDACs, the underlying mechanisms remain elusive. Using cryo-electron microscopy (cryo-EM), cross-linking mass spectrometry (XL-MS), and biochemistry analyses, we established class I HDACs as novel TRiC substrates and elucidate TRiC-assisted folding of HDAC1 and HDAC3 during its ATPase cycle, orchestrated by distinct co-chaperone and cofactor networks. In the closed TRiC chamber, both HDAC1 and HDAC3 adopt near-native states with shared binding interfaces. However, their open-state configurations diverge: Hsp70 and PDCD5 engage atop and within TRiC, respectively, for HDAC3, whereas prefoldin (PFD) binds atop TRiC for HDAC1, suggesting roles in substrate delivery and folding modulation. Furthermore, an unexpected bent conformation of CCT4, detected in TRiC-HDAC1 complex, may facilitate co-chaperone dissociation from TRiC. In contrast, HDAC8 folds independently of TRiC. Our study reveals the mechanism governing TRiC-assisted folding of class I HDACs in orchestration of dynamic co-chaperone/cofactor network, shielding new lights on the sophisticated regulatory landscape of TRiC, and open promising avenues for designing peptides or small molecules to selectively modulate TRiC-assisted folding of class I HDACs and other substrates.

molecular biology↗

Comparative Analysis of the Effects of PSPH and PHGDH Inhibitors on Tumor Cell Proliferation

Serine metabolism plays a critical role in supporting the rapid proliferation of tumor cells, with PHGDH recognized as a key rate-limiting enzyme and therapeutic target. However, whether its antitumor effects are solely dependent on serine metabolism remains under debate. In this study, we systematically compared the effects of PHGDH versus PSPH inhibitors on intracellular serine levels and tumor cell proliferation. Although multiple PSPH inhibitors significantly reduced intracellular serine concentrations, they failed to effectively inhibit cell proliferation. In contrast, PHGDH inhibitors exhibited robust antiproliferative activity under both serine-deprived and serine-replenished conditions. Further supplementation with -ketoglutarate, a downstream metabolite of PHGDH, partially reversed this inhibitory effect. These findings suggest that the antitumor activity of PHGDH inhibitors is not solely attributable to serine metabolism inhibition, but rather results from the coordinated disruption of multiple metabolic pathways, offering a novel perspective for metabolism-targeted cancer therapy.

cancer biology↗

MPBind: Multitask Protein Binding Site Prediction by Protein Language Models and Equivariant Graph Neural Networks

Proteins interact with a variety of molecules, including other proteins, DNAs, RNAs, ligands, ions, and lipids. These interactions play a crucial role in cellular communication, metabolic regulation, immune response, and structural integrity, making proteins fundamental to nearly all biological functions. Accurately predicting protein binding (interaction) sites is essential for understanding protein interactions and functions. Here, we introduce MPBind, a multitask protein binding site prediction method, which integrates protein language models (PLMs) that can extract structural and functional information from sequences and equivariant graph neural networks (EGNNs) that can effectively capture geometric features of 3D protein structures. Through multitask learning, it can predict binding sites on proteins that interact with five key categories of binding partners: proteins, DNA/RNA, ligands, lipids, and ions, which is more comprehensive than most existing task-specific methods that can predict only one or a few kinds of binding sites. Moreover, MPBind outperforms both general bind site prediction methods and task-specific binding site prediction methods.

bioinformatics↗

Impairment of the blood brain barrier accelerates a negative ultraslow potential in the locust CNS

Insects provide useful models for investigating evolutionarily conserved mechanisms underlying electrical events associated with brain injury and death. Spreading depolarizations (SD) are transient events that propagate through neuropil whereas the negative ultraslow potential (NUP) is sustained and reflects accumulating damage in the tissue. We used the locust, Locusta migratoria, to investigate ion homeostasis at the blood brain barrier (BBB) during SD and NUP induced by treatment with the Na+/K+-ATPase inhibitor, ouabain. We found that sustained SD caused by the metabolic inhibitor, sodium azide, was associated with a large reduction of K+ efflux through the BBB at ganglia (= grey matter) but not at connectives (= white matter). This was accompanied by a large increase in tissue resistivity but no conductance changes of identified motoneuron dendrites in the neuropil. Males recovered more slowly from ouabain-induced SD, as previously described for anoxic SD. Impairment of barrier functions of the BBB pharmacologically with cyclosporin A or DIDS, or by cutting nerve roots, accelerated the NUP, thus promoting earlier and more frequent SD, but had no effect on the temporal parameters of SD. We conclude that the mechanisms underlying onset and recovery of SD are minimally affected by the damage associated with the NUP. We suggest that future research using tissue-specific genetic approaches in Drosophila to target identified molecular structures of the BBB are likely to be fruitful. New and NoteworthyInhibition of the sodium pump in the locust CNS causes repetitive spreading depolarization (SD) and a negative ultraslow potential (NUP) providing a model for investigation of phenomena relevant to human health. We show that impairment of the blood brain barrier accelerates the NUP but has no impact on the trajectory of SD events. Hence, rapid mechanisms of onset and recovery of ion homeostasis occur against a background of slowly increasing neural damage. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=169 SRC="FIGDIR/small/648410v1_ufig1.gif" ALT="Figure 1"> View larger version (26K): org.highwire.dtl.DTLVardef@1d8174corg.highwire.dtl.DTLVardef@1e1a57aorg.highwire.dtl.DTLVardef@13719a9org.highwire.dtl.DTLVardef@75b641_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗

Mechanistic Study of palmatine in Regulating Pyroptosis in Sepsis Cells via Signaling Pathways

This study aims to investigate whether palmatine has a potential effect on sepsis-related pyroptosis in patients through relevant signaling pathways. Initially, the study explores the differential genes associated with pyroptosis in sepsis patients, along with their related enrichment processes, biological behaviors, and functional pathways. Patients with sepsis pyroptosis are then classified into subgroups based on pyroptosis-related genes to analyze the biological differences between these subtypes. Furthermore, the signaling pathways and biological functions associated with palmatine are studied to assess whether there are functional similarities or overlaps with the signaling pathways and biological behaviors observed in patients with sepsis pyroptosis. Finally, the findings are validated through wet-lab experiments. The results reveal that the signaling pathways related to palmatine partially overlap with those observed in sepsis pyroptosis patients, indicating that palmatine may influence sepsis pyroptosis through these pathways. Parmatine may improve the prognosis of sepsis by affecting the immune function of PRKACA, PTGS2, NLRP3, HSP90AA1 and PTPN22.

bioinformatics↗

Cas12a/3 crRNAs RNP transformation enables transgene-free multiplex genome editing, long deletions, and inversions in citrus chromosome in the T0 generation

Citrus canker, caused by Xanthomonas citri subsp. citri (Xcc), is a devastating disease worldwide. Previously, we successfully generated canker-resistant Citrus sinensis cv. Hamlin lines in the T0 generation, achieving a mutation efficiency of 97.4%. This was achieved through the transformation of embryogenic protoplasts using the Cas12a/1 crRNA ribonucleoprotein (RNP) system to edit the canker susceptibility gene, CsLOB1, which led to small indels. Here, we transformed embryogenic protoplasts of Hamlin with Cas12a/3 crRNAs RNP, resulting in 100% efficiency in editing the CsLOB1 gene in the T0 generation. Among the 10 transgene-free genome-edited lines, long deletions were obtained in five lines. Additionally, inversions were observed in three of the five edited lines with long deletions, but not in any edited lines with short indel mutations, suggesting long deletions are required for inversions. Biallelic mutations were observed for each of the three target sites in 4 of the 10 edited lines when 3 crRNAs were used, demonstrating that transformation of embryogenic citrus protoplasts with Cas12a/3 crRNAs RNP can be very efficient for multiplex editing. Our analysis revealed the absence of off-target mutations in the edited lines. These cslob1 mutant lines were canker-resistant and no canker symptoms were observed after inoculation with Xcc and Xcc growth was significantly reduced in the cslob1 mutant lines compared to the wild type plants. Taken together, Cas12a/3 crRNAs RNP transformation of embryogenic protoplasts of citrus provides a promising solution for transgene-free multiplex genome editing with high efficiency and for deletion of long fragments.

plant biology↗

Palytoxin Evokes Reversible Spreading Depolarization in the Locust CNS

Spreading depolarization (SD) describes the near-complete depolarization of CNS neural cells as a consequence of chemical, electrical, and metabolic perturbations. It is well-established as the central mechanism underlying insect coma and various mammalian neurological dysfunctions. Despite significant progress in our understanding, the question remains: which cation channel, if any, generates SD in the CNS? Previously, we speculated that the sodium-potassium ATPase (NKA) might function as a large-conductance ion channel to initiate SD in insects, potentially mediated by a palytoxin (PLTX)-like endogenous activator. In the current study, we evaluate the effectiveness and properties of PLTX as an SD initiator in L. migratoria. Whereas bath-applied PLTX failed to ignite SD, direct injection into the neuropil triggered SD in 57% of the preparations. Notably, PLTX-induced SD onset was significantly more rapid compared to ouabain injection and azide controls, though their electrophysiological features remained similar. Furthermore, PLTX-induced SD was recoverable and resulted in a greater frequency of repetitive SD events compared to ouabain. Surprisingly, prior PLTX treatment disrupted the onset and recovery of subsequent SD evoked by other means. PLTX injection could attenuate the amplitude and hasten the onset time of azide-induced SD. Such an effect is associated with a complete inhibition at higher doses of subsequent anoxic SD induced through azide treatment or submersion. These results show that PLTX can trigger repetitive and reversible SD-like events in locusts and simultaneously interfere with anoxic SD occurrence. We suggest that the well-documented NKA pump conversion into an open non-selective cationic channel is a plausible mechanism of SD activation in the locust CNS, warranting additional investigations.

neuroscience↗

A new method and application of PacBio sequencing for low copy and difficulty preparation plasmids.

The Single Molecule Real Time (SMRT) system developed by Pacific Biosciences applies the principle of synthesis while sequencing and uses the SMRT chip as the sequencing carrier. The high starting amount and good integrity of DNA required by PacBio library construction has always been a headache. Generally, the total loading volume of PacBio sequencing is 10g, and the concentration is not less than 200ng/L, which is a huge challenge for low-copy plasmids. Tight plasmid means that when the bacterial chromosome replicates once, the plasmid replicates once, and each bacterium only contains 1 to 2 plasmids. The replicon of the plasmid determines the copy number of the plasmid. Low copy plasmids should produce 0.2-1 g DNA per ml of LB culture. Low-copy plasmids play a key role in gene synthesis. When vectors are used for expression or other purposes, low-copy plasmids are used to reduce resource consumption caused by plasmid expansion. Low-copy plasmids are also used when plasmids have lethal gene clones. In order to solve the problem of low copy plasmid library database construction in PacBio, we used Phi29 polymerase to perform multiple substitution amplification of low copy plasmid, so as to obtain a large number of high molecular weight DNA to meet the computer requirements of PacBio. In addition, this study also established a PacBio sequencing method for bacterial fluids without the need for plasmid extraction steps, thereby reducing time and money costs.

molecular biology↗

A method for filtering abnormal modified base calling in Oxford Nanopore Technologies sequencing

Backgroundgene synthesis sequencing using the long-read Oxford Nanopore Technologies (ONT) provides a cost-effective option for gene synthesis quality control. Despite the advantage of using long reads, however, accurate base calling is influenced by modified bases. ResultsWe introduce a method for filtering abnormal modified base calling in Oxford Nanopore Technologies sequencing. This method is based on the mapping results and perform an exact binomial test on the proportion of single base forward and reverse chain depth to determine the presence of abnormal modified base calling. Based on Sanger sequencing results, this method detected 96.79% of effective abnormal modified base calling, and the accuracy of gene synthesis sequencing increased from 99.40% before calibration to 99.98% after calibration, significantly reducing the proportion of requiring secondary gene synthesis sequencing. ConclusionThis method can accurately filter abnormally modified base calling sites, reduce the proportion of using Sanger for secondary sequencing, thereby saving costs, and improving efficiency.

bioinformatics↗

Effects of arbuscular mycorrhizal fungi on nitrogen uptake in cotton (Gossypium hirsutum L.) under low-nitrogen conditions

SummaryO_LICotton is an important global cash crop whose yield and quality are highly influenced by soil nitrogen. Therefore, examining the interactions between roots and arbuscular mycorrhizal fungi (AMF) under reduced nitrogen conditions is of great significance. C_LIO_LIWe investigated the effects of nitrogen application (0, 250, and 375 kg{middle dot} hm-2) on the AMF infection rate of cotton, the nitrogen content of each organ, root morphological characteristics and biomass, soil extracellular enzyme activity, and soil carbon and nitrogen content using a compartmentalized culture system. C_LIO_LIThe contribution of AMF to plant nitrogen was 10.40, 22.72, and 16.67% under high, low, and no nitrogen treatments, respectively. Under low-nitrogen conditions, the symbiosis between AMF and roots increased root surface area, tip number, branch number, mean diameter, and biomass; and increased soil extracellular enzyme activity (protease, NAG, PER, and PPO), the microbial biomass carbon-to-nitrogen ratio, active carbon content, and the soil nitrogen mineralization rate. Soil NO3--N, NH4+-N, and organic nitrogen content decreased, whereas the absorption of NO3--N by AMF hyphae was higher than that of NH4+-N. C_LIO_LIUnder low-nitrogen conditions, AMF promoted the decomposition of soil organic matter and the transformation of soil nitrogen through the action of hyphal microorganisms. C_LI

plant biology↗