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Biology subjects

Wei, F.

Publications and source records attributed to Wei, F..

At least 37 records · Page 2Linked to original sources

Combining Glycosidases and Nanopore Technology for Glycan Sequencing

The efficient characterization of glycan structures remains a critical challenge. Direct glycan sequencing technologies with improved sensitivity and throughput are still needed. Here, we propose a glycan sequencing strategy based on glycosidase -assisted nanopore sensing. We used engineered nanopore -hemolysin (M113R/T115A), which provided high-resolution discrimination of monosaccharide volume differences and sensitivity to variations in glycan chain length. By utilizing the specificity of glycosidases, we sequentially hydrolyzed the terminal residues of the glycan chains and detected the characteristic shifts in electrical signals generated by the translocation of hydrolysis products. The accuracy of recognition of hydrolysis fragments achieved over 90 % using machine learning. This allowed us to efficiently and conveniently determine the sequence of consecutive monosaccharide units in the glycan chains. Based on this principle, we conducted a proof-of-concept demonstration on actual samples and verified the accuracy via HPLC-MS. We achieved the sequencing of consecutive units in glycan chains, confirming the theoretical feasibility of glycosidase -assisted nanopore glycan sequencing. With future optimization, the development of arrayed nanopore glycan sequencing technology based on hydrolysis strategy will provide an innovative approach for rapid decoding of glycans, which could promote the progress of glycomics research and glycobiology.

biochemistry↗

Probing Biomass Precursor Synthesis as a Key Factor in Microbial Adaptation to Unadapted Carbon Sources

Industrial microorganisms often face challenges in utilizing renewable substrates such as methanol, formate, and xylose. We present findings that the proportion of biomass precursors that must be synthesized from unadapted carbon sources is a critical determinant of the evolutionary driving force and minimal substrate requirements, using a new computational framework, AdaptUC. We predict metabolic engineering strategies for Adaptive Laboratory Evolution (ALE). These strategies enable microorganisms to co-utilize an adapted co-substrate and an unadapted carbon source or, in some cases, rely exclusively on the unadapted source. AdaptUC was validated through experimental records and literature, confirming its effectiveness in identifying gene knockout strategies. Case studies in Escherichia coli and Corynebacterium glutamicum highlight superior strategies with higher driving forces and reduced substrate requirements. This method has the potential to transform industrial biosynthesis by enabling more efficient use of renewable carbon sources. Graphic Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=80 SRC="FIGDIR/small/619944v1_ufig1.gif" ALT="Figure 1"> View larger version (36K): org.highwire.dtl.DTLVardef@36fe02org.highwire.dtl.DTLVardef@5e73fdorg.highwire.dtl.DTLVardef@110ffdaorg.highwire.dtl.DTLVardef@10d45dc_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗

Universal function of WRI1 involved in integrated regulation of multiple latex metabolism pathways in Natural Rubber

Hevea brasiliensis and Taraxacum kok-saghyz are sources of nature rubber (NR) and recent research has focused on finding a method to increase NR quality and production. NR consists mainly of cis-1,4-polyisoprene, which is synthesized from sucrose by a series of reactions during carbon metabolism. WRINKLED1 (WRI1) is a transcription factor (TF) that coordinates many genes involved in carbon metabolism and lipid biosynthesis. Here, we isolated and characterized two orthologues of WRI in rubber-producing plants H. brasiliensisa and T. kok-saghyz, which are highly expressed in their latex. Subcellular localization and ectopic expression in Arabidopsis thaliana indicated that the TFs, HbWRI1 and TkWRI1, are involved in lipid accumulation. Overexpression of HbWRI1 and TkWRI1 in T. kok-saghyz substantially enhanced NR quality and production, including dry rubber content, molecular weight, and the diameter of rubber particles in the latex. Conversely, they were decreased in TkWRI1 repression. Furthermore, based on the activated expression in transgenic T. kok-saghyz latex and the existence of AW-box element in the promoter regions, 16 direct downstream genes of HbWRI1 and TkWRI1 were identified by a dual-luciferase reporter assay and yeast one-hybrid assay, and their products were responsible for both NR biosynthesis and lipid metabolism. These results reveal a regulatory module that HbWRI1 and TkWRI1 TFs can positively regulate NR quality and production in T. kok-saghyz latex by synergistically regulating the entire NR biosynthesis. This module is expected to be utilized to develop superior varieties to enhance NR quality and production.

biochemistry↗

Constructing a Norm for Children's Scientific Drawing: Distribution Features Based on Semantic Similarity of Large Language Models

The use of childrens drawings to examining their conceptual understanding has been proven to be an effective method, but there are two major problems with previous research: 1. The content of the drawings heavily relies on the task, and the ecological validity of the conclusions is low; 2. The interpretation of drawings relies too much on the subjective feelings of the researchers. To address this issue, this study uses the Large Language Model (LLM) to identify 1420 childrens scientific drawings (covering 9 scientific themes/concepts), and uses the word2vec algorithm to calculate their semantic similarity. The study explores whether there are consistent drawing representations for children on the same theme, and attempts to establish a norm for childrens scientific drawings, providing a baseline reference for follow-up childrens drawing research. The results show that the representation of most drawings has consistency, manifested as most semantic similarity>0.8. At the same time, it was found that the consistency of the representation is independent of the accuracy (of LLMs recognition), indicating the existence of consistency bias. In the subsequent exploration of influencing factors, we used Kendall rank correlation coefficient to investigate the effects of "sample size", "abstract degree", and "focus points" on drawings, and used word frequency statistics to explore whether children represented abstract themes/concepts by reproducing what was taught in class. It was found that accuracy (of LLMs recognition) is the most sensitive indicator, and data such as sample size and semantic similarity are related to it; The consistency between classroom experiments and teaching purpose is also an important factor, many students focus more on the experiments themselves rather than what they explain. In addition, most children tend to use examples they have seen in class to represent more abstract themes/concepts, indicating that they may need concrete examples to understand abstract things.

scientific communication and education↗

Drug inhibition and substrate alternating flipping mechanisms of human VMAT2

Vesicular monoamine transporters (VMAT1/2) are responsible for loading and packaging monoamine neurotransmitters into synaptic vesicles, including serotonin (5-HT), dopamine (DA), norepinephrine, and histamine. Dysregulation of VMAT2 within the central nervous system can lead to schizophrenia, mood disorders, and Parkinsons disease, due to the imbalances of these monoamine neurotransmitters. Medications such as tetrabenazine (TBZ) and valbenazine (VBZ) targetting VMAT2 are approved for treating chorea associated with Huntingtons disease and Tardive Dyskinesia. Our cryo-EM studies and molecular dynamics (MD) simulations on VMAT2 bound to drug inhibitors (TBZ and VBZ) and substrates (5-HT and DA), unveil the inhibition mechanism of VMAT2, alternating flipping mechanism of substrates during loading, translocation, and release, as well as the interplay between protonation of crucial acidic residues and substrate release. These findings enhance the understanding of VMAT-mediated monoamine neurotransmitter transport, fostering drug development for neurological and neuropsychiatric disorders, with a specific emphasis on VMATs.

neuroscience↗

Methionine availability influences essential H3K36me3 dynamics during cell differentiation

Histone modifications are integral to epigenetics through their influence on gene expression and cellular status. While its established that metabolism, including methionine metabolism, can impact histone methylation, the direct influence of methionine availability on crucial histone marks that determine the epigenomic process remains poorly understood. In this study, we demonstrate that methionine, through its metabolic product, S-adenosylmethionine (SAM), dynamically regulates H3K36me3, a cancer-associated histone modification known to influence cellular status, and myogenic differentiation of mouse myoblast cells. We further demonstrate that the methionine-dependent effects on differentiation are mediated in part through the histone methyltransferase SETD2. Methionine restriction leads to preferential decreases in H3K36me3 abundance and genome accessibility of genes involved in myogenic differentiation. Importantly, the effects of methionine restriction on differentiation and chromatin accessibility can be phenocopied by the deletion of Setd2. Collectively, this study demonstrates that methionine metabolism through its ability to be sensed by chromatin modifying enzymes can have a direct role in influencing cell fate determination.

cell biology↗

Mass spectrometry imaging links interxylary cork formation with phytochemical distribution in Scutellaria baicalensis

Interxylary cork, an anomalous cork structure of plant, is occasionally seen in older roots of Scutellaria baicalensis Georgi (Lamiaceae). Xylem tissues encircled by interxylary corks gradually decay. Efforts have been made to elucidate the development of interxylary cork in S. baicalensis, but the variation of phytochemical accumulation in different root tissues segmented by interxylary cork has not been studied. In this investigation, mass spectrometry imaging was employed to visualize the in situ phytochemicals in the decayed root of S. baicalensis (Kuqin). A special flavonoid was observed to show especially high mass intensity in the cork region, and its spatial distribution was regarded as a reflection of cork development. Interxylary corks were found to be successively formed in the root of S. baicalensis. After the continuous formation of interxylary corks, root tissues were divided into different parts by interxylary corks, including the non-decayed part, slightly decayed part and severely decayed part. Interestingly, pharmaceutically important flavonoids presented different accumulation tendencies in tissues of different decaying degrees. Owing to the non-targeted analytical function of mass spectrometry imaging, the holistic difference of chemical composition of decayed and non-decayed tissues of Kuqin was deciphered. To our knowledge, this is the first experiment that maps out the successive formation of interxylary corks in S. baicalensis using mass spectrometry imaging. Also, our research successfully correlates plant anatomy with the spatial distribution of phytochemicals, which sets a good example for the exploration of plant science from the dimension of spatial information.

biochemistry↗

Mitochondrial translation regulates terminal erythroid differentiation by maintaining iron homeostasis

A lack of the mitochondrial tRNA taurine modifications mediated by mitochondrial tRNA translation optimization 1 (Mto1) was recently shown to induce proteostress in embryonic stem cells. Since erythroid precursors actively synthesize the hemoglobin protein, we hypothesized that Mto1 dysfunctions may result in defective erythropoiesis. Hematopoietic-specific Mto1 conditional knockout (cKO) mice were embryonic lethal due to niche-independent defective terminal erythroid differentiation. Mechanistically, mitochondrial oxidative phosphorylation complex-I was severely defective in the Mto1 cKO fetal liver and this was followed by cytoplasmic iron accumulation. Overloaded cytoplasmic iron promoted heme biosynthesis and enhanced the expression of embryonic hemoglobin proteins, which induced an unfolded protein response via the IRE1-Xbp1 signaling pathway in Mto1 cKO erythroblasts. An iron chelator rescued erythroid terminal differentiation in the Mto1 cKO fetal liver in vitro. The new point of view provided by this novel non-energy-related molecular mechanism may lead to a breakthrough in mitochondrial research.

cell biology↗

Identification of a carbohydrate-recognition motif of purinergic receptors

As a major class of biomolecules, carbohydrates play indispensable roles in various biological processes. However, it remains largely unknown how carbohydrates directly modulate important drug targets, such as G-protein coupled receptors (GPCRs). Here, we employed P2Y purinoceptor 14 (P2Y14), a drug target for inflammation and immune responses, to uncover the sugar nucleotide activation of GPCRs. Integrating molecular dynamics simulation with functional study, we identified the uridine diphosphate (UDP)-sugar-binding site on P2Y14, and revealed that a UDP-glucose might activate the receptor by bridging the transmembrane helices (TM) 2 and 7. Between TM2 and TM7 of P2Y14, a conserved salt bridging chain (K2.60-D2.64-K7.35-E7.36, KDKE) was identified to distinguish different UDP-sugars, including UDP-glucose, UDP-galactose, UDP-glucuronic acid and UDP-N-acetylglucosamine. We identified the KDKE chain as a conserved functional motif of sugar binding for both P2Y14 and P2Y purinoceptor 12 (P2Y12), and then designed three sugar nucleotides as agonists of P2Y12. These results not only expand our understanding for activation of purinergic receptors but also provide insights for the carbohydrate drug development for GPCRs.

molecular biology↗

Nucleotide metabolism is linked to cysteine availability

The small molecule erastin inhibits the cystine-glutamate antiporter, system xc-, which leads to intracellular cysteine and glutathione depletion. This can cause ferroptosis, which is an oxidative cell death process characterized by uncontrolled lipid peroxidation. Erastin and other ferroptosis inducers have been shown to affect metabolism but the metabolic effects of these drugs have not been systematically studied. To this end, we investigated how erastin impacts global metabolism in cultured cells and compared this metabolic profile to that caused by the ferroptosis inducer RSL3 or in-vivo cysteine deprivation. Common among the metabolic profiles were alterations in nucleotide and central carbon metabolism. Supplementing nucleosides to cysteine-deprived cells rescued cell proliferation in certain contexts, showing that these alterations to nucleotide metabolism can affect cellular fitness. While GPX4 inhibition caused a similar metabolic profile as cysteine deprivation, nucleoside treatment did not rescue cell viability or proliferation under RSL3 treatment, suggesting that these metabolic changes have varying importance in different scenarios of ferroptosis. Together, our study shows how global metabolism is affected during ferroptosis, and points to nucleotide metabolism as an important target of cysteine deprivation.

cell biology↗

A point mutation in Chl biosynthesis gene Mg-chelatase I subunit influences on leaf color and metabolism in strawberry

Magnesium chelatase catalysis the insertion of magnesium into protoporphyrin IX is a vital step in chlorophyll biogenesis. It consists of three subunits, CHLI, CHLD and CHLH. The CHLI subunit is an ATPase and hydrolysis ATP in the catalysis. However, its key point on influencing flavonoid biosynthesis and chlorophyll accumulation under different light density was still unknown. In this study, we identified an N-Ethyl-N-nitrosourea (ENU) mutant, p240 from strawberry Fragaria pentaphylla that has yellow-green leaves and lower chlorophyll level. We verified the mutation occurs in the 186th amino acid of CHLI subunit, which is conserved in most photosynthetic organism. Mutants generated from RNAi and CRISPR/Cas9 gene editing confirmed this phenotype. In addition, we found that FpCHLI was localized in chloroplast and its subcellular location have not been changed by mutation. Further study showed that the interaction between FpCHLI and FpCHLD were not affected by mutagenesis. In contrast, all types of mutants showed reduced ATPase and magnesium chelatase activity indicating mutagenesis decreased enzymatic activities. Furthermore, mutagenesis suppressed the biosynthesis of Mg-proto IX. Metabolites analysis of gene knock-out mutant and WT revealed that CHLI may help to keep stabilizing the flavonoid level in leaves. Furthermore, both p240 and chli mutants are light sensitive, which has yellow leaves under high light but pale green leaves under poor light. The photosynthesis ability of mutants was also increased under shade. Moreover, stomatal apertures of mutants were wider than WT. Taken together, these results suggest that CHLI plays an important role in both leaf coloration and metabolism.

plant biology↗

Extensive diversity of RNA viruses in ticks revealed by metagenomics in northeastern China

Recently, several emerging tick-borne viruses have been identified to be associated with human diseases in northeastern China. Here, we used metagenomics to investigate the virome diversity in Haemaphysalis japonica, H. conicinna, Dermacentor silvarum, and Ixodes persulcatus ticks in northeastern China. A total of 22 RNA viruses were identified and belonged to more eight viral families, including four each in Nairoviridae and Phenuiviridae, three each in Flaviviridae, Rhabdoviridae, and Solemoviridae, two in Chuviridae, and one each in Partitiviridae, Tombusviridae, and unclassified. Of them, eight viruses were novel species, belonging to Nairoviridae (Jian nairovirus and Yichun nairovirus), Phenuiviridae (Mudanjiang phlebovirus), Rhabdoviridae (Tahe rhabdovirus 1-3), Chuviridae (Yichun mivirus), and Tombusviridae (Yichun tombus-like virus), and five members were established human pathogens, including Alongshan virus, tick-borne encephalitis virus, Songling virus, Beiji nairovirus, and Nuomin virus. I. persulcatus ticks had significant higher viral species than those in H. japonica, H. concinna, and D. silvarum ticks. Significant differences in tick viromes were observed among Daxingan, Xiaoxingan and Changbai mountains. These findings showed an extensive diversity of RNA viruses in ticks in northeastern China, revealed potential public health threats from the emerging tick-borne viruses. Further studies are needed to explain the natural circulation and pathogenicity of these viruses.

microbiology↗

Sympathetic blockage attenuates fasting-induced hepatic steatosis

Background and AimAlthough it is clear that the central nervous system coordinates whole-body metabolism, the neural mechanism for hepatic steatosis remains unclear. This study is aimed to explore the neural mechanism of fasting-induced hepatic steatosis. MethodsMice were pretreated with 6-hydroxydopamine to block sympathetic nerve activity before fasting, and explored the potential effects of chemical sympathectomy on fasting-induced hepatic steatosis and transcriptional changes. ResultsProlonged fasting led to obvious hepatic steatosis, low core temperature, and similar effects to cold-induced white adipose lipolysis. The alterations in hepatic mRNA expression revealed that the hepatic lipid accumulation did not result from the increase of hepatic lipogenesis or the decrease of fatty acid oxidation but from the enhanced fatty acid uptake as indicated by the upregulation of CD36. Blockage of the sympathetic nervous system via chemical sympathectomy attenuated fasting-induced hepatic steatosis and suppressed CD36 upregulation in the liver, but did not obviously alter the expression of genes associated with lipogenesis or fatty acid oxidation. ConclusionsThese findings indicate that the sympathetic nervous system orchestrates the mechanism for fasting-induced hepatic steatosis via modulating CD36 expression and adipose fat trafficking into the liver, which provides clues to reveal new targets for fatty liver diseases. HIGHLIGHTSO_LIProlonged fasting causes obvious hepatic steatosis C_LIO_LISympathectomy attenuates fasting-induced hepatic steatosis C_LIO_LISympathectomy attenuates steatosis via suppressing CD36 upregulation C_LI IN BRIEFProlonged fasting contributes to sympathetic hyperactivity, but its role in the pathogenesis of hepatic steatosis remains unclear. Here, we found prolonged fasting led to obvious hepatic steatosis, low core temperature, and subsequent sympathetic stimulation that promoted white adipose lipolysis, hepatic upregulation of CD36, and adipose fat trafficking into the liver.

pathology↗

An early Cambrian polyp reveals an anemone-like ancestor for medusozoan cnidarians

Extant cnidarians are a disparate phylum of non-bilaterians and their diploblastic body plan represents a key step in animal evolution. Anthozoans (anemones, corals) are benthic polyps, while adult medusozoans (jellyfishes) are dominantly pelagic medusae. A sessile polyp is present in both groups and is widely conceived as the ancestral form of their last common ancestor. However, the nature and anatomy of this ancestral polyp, particularly of medusozoans, are controversial, owing to the divergent body plans of both groups in the extant lineages and the rarity of medusozoan soft tissues in the fossil record. Here we redescribe the enigmatic Conicula striata Luo et Hu from the early Cambrian Chengjiang biota, south China, which has previously been interpreted as a polyp, lophophorate or deuterostome. We show that C. striata possessed features of both anthozoans and medusozoans. Its stalked polyp and fully encasing conical, annulated organic skeleton (periderm) are features of medusozoans. However, the gut is partitioned by [~]28 mesenteries, and has a tubular pharynx, resembling anthozoans. Our phylogenetic analysis recovers C. striata as a stem medusozoan, indicating that the enormously diverse medusozoans were derived from an anemone-like ancestor, with the pharynx lost and number of mesenteries reduced prior to the origin of crown group Medusozoa.

paleontology↗

Reversable deformation of artificial cell colony for muscle behavior mimicry triggered by actin polymerization

The mimicry of living tissues from artificial cells is beneficial to understanding the interaction mechanism among cells, as well as holding great potentials in the tissue engineering field. Self-powered artificial cells capable of reversible deformation are developed by encapsulating living mitochondria, actin proteins, and methylcellulose. Upon the addition of pyruvate molecules, the mitochondria produce ATP molecules as energy sources to trigger the polymerization of actin. ATP molecules were produced by mitochondria (2.76x1010/ml) with the concentrations of 35.8{+/-}3.2 {micro}M, 158.2{+/-}19.3 {micro}M and 200.7{+/-}20.1 M by adding pyruvate molecules with the concentration of 3 M, 12 M and 21 M, respectively. The reversible deformation of artificial cells is experienced with spindle shape resulting from the polymerization of actins to form filaments adjacent to the lipid bilayer, subsequently back to spherical shape resulting from the depolymerization of actin filaments upon laser irradiations. The linear colonies composed of these artificial cells exhibit collective contraction and relaxation behavior to mimic muscle tissues. At the stage of maximum contraction, the long axis of each GUV is in parallel to each other. All colonies are synchronized in the contraction phase. The deformation of each GUV in the colonies is influenced by its adjacent GUVs. The muscle-like artificial cell colonies paved the path to develop sustainably self-powered artificial tissues in the field of tissue engineering.

bioengineering↗

Plasma Contains Ultra-short Single-stranded DNA in Addition to Nucleosomal cfDNA

Plasma cell-free DNA is a widely used biomarker for diagnostic screening. We introduce uscfDNA-seq, a single-stranded cell-free DNA NGS pipeline, which bypasses previous limitations to reveal a novel population of ultrashort single-stranded cell-free DNA in plasma with a modal size of 50nt. This species of cfDNA aligns predominantly to the nuclear genome and could potentially be used for novel biomarker discovery.

genomics↗

YAP and TAZ are transcriptional co-activators of AP-1 proteins and STAT3 during breast cellular transformation

The YAP and TAZ paralogues are transcriptional co-activators recruited to target sites, primarily by TEAD proteins. Here, we show that YAP and TAZ are also recruited by JUNB and STAT3, key factors that mediate an epigenetic switch linking inflammation to cellular transformation. YAP and TAZ directly interact with JUNB and STAT3 via a WW domain important for transformation, co-occupy many target sites in vivo via AP-1 and (to a lesser extent) STAT3 sequence motifs, and stimulate transcriptional activation by AP-1 proteins. A few target sites are YAP- or TAZ-specific, and they are associated with different sequence motifs and gene classes. YAP/TAZ, JUNB, and STAT3 directly regulate a common set of target genes that overlap, but are distinct from, those regulated by YAP/TAZ and TEADs. The set of genes regulated by YAP/TAZ, STAT3, and JUNB is associated with poor survival in breast cancer patients with the triple-negative form of the disease.

molecular biology↗

A Whole-Genome Association Approach for Large-scaled Inter-species Trait

Genome wide association studies (GWAS) have provided an avenue for the association between common genetic variants and complex traits. However, using SNP as a genetic marker, GWAS has been confined to detect genetic basis traits only for within species but not for the large-scale inter-species traits. Here, we propose a practical statistical approach that is using kmer frequencies as the genetic markers to associate genetic variants with large scale inter-species traits. We applied this new approach to the trait of chromosome number in 96 mammalian proteomes, and we prioritized 130 genes including TP53 and BAD, of which 6 were candidate genes. These genes were proved to be associated with cellular reaction of DNA double-strand breaks caused by chromosome fission/fusion. Our study provides a new effective genomic strategy to perform association studies for large-scaled inter-species traits, using the chromosome number as a case. We hope this approach could provide exploration for broadly widely traits.

genomics↗