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Biology subjects

Cui, F.

Publications and source records attributed to Cui, F..

At least 19 recordsLinked to original sources

Intrinsic DNA codes govern distinct modes of nucleosome-transcription factor interactions

The interplay between transcription factors (TFs) and nucleosomes is central to gene regulation, yet most studies adopt a protein-centric perspective that largely overlooks DNA sequence contributions. Here, we identify four distinct nucleosomal DNA classes, including the canonical WW/SS pattern (W = A/T, S = G/C). All four nucleosome types are widespread across the human genome both in vivo and in vitro. Nucleosomes sharing the same pattern are rotationally in phase, whereas different patterns exhibit specific rotational offsets, revealing distinct DNA-encoded codes for nucleosome positioning. Analysis of 747 TFs across eukaryotes shows that the WW/SS and anti-WW/SS patterns are strongly associated with TF binding in chromatin. Differences in the proportions of these two patterns, quantified as {Delta}NPS values, correlate closely with in vitro nucleosome occupancy. Integrating {Delta}NPS with in vivo nucleosome occupancy uncovers four distinct modes of nucleosome-TF interaction and provides new insight into nucleosome-depleted regions around TF binding sites.

bioinformatics↗

Machine-learning-based determination of sex-related bladder cancer biomarkers

Bladder cancer exhibits sex-specific behavior, occurring more frequently in males but progressing to advanced stages more commonly in females. The activation of sex hormone receptors may explain these differences, but the exact genetic drivers remain poorly understood. Furthermore, current bladder cancer biomarkers have inconsistent sensitivities and specificities in practice, making early diagnosis a challenge. This study approaches bladder cancer biomarker discovery through machine learning techniques on gender and disease-stratified RNA-seq data. Training sets limited to differentially expressed genes were subjected to four different feature selection methods: differential gene expression analysis adjusted p-value, recursive feature elimination with support vector machine, logistic regression, and an optimized random forest procedure. Gene panels were compared and aggregated across selection strategies and cross-validation folds to identify robust biomarkers for sex-specific bladder cancer development and progression. When applied to unseen datasets and limited to 50 genes or less, male and female-specific panels achieved areas under the receiver operating characteristic curve of 0.932 and 0.914, respectively, in distinguishing bladder cancer samples from non-tumor controls. Genes such as PRAC1 and PCDH11Y were identified as high-impact predictors related to sex hormones or chromosomes for male tumor development. In the female-specific panel, genes related to aberrant androgen signaling across tumor types like AR, PLXNA1, USP54, and PMEPA1 were influential. These results offer potential targets for further in vivo/vitro experimentation and provide a framework for constructing generalizable, high-performance gene panels for bladder cancer diagnosis and prognosis.

bioinformatics↗

Locus-specific transcriptional regulation of transposable elements by p53

The tumor suppressor p53 protects genomic integrity in part by regulating transposable elements (TEs). Most studies of p53-TE interactions rely on synthetic DNA and reporter assays, which estimate expression only at the family or subfamily level and lack locus-specific resolution. To address this limitation, we developed a computational pipeline for ChIP-seq and RNA-seq analysis that employs advanced algorithms to accurately assign short reads mapping to multiple genomic locations. This approach enables precise quantification of TE transcripts at the locus level. By integrating p53 ChIP peaks with differentially expressed TE transcripts, we identified retroelements directly regulated by p53. Applying this framework to lung fibroblast IMR90 and colon cancer HCT116 cells treated with p53 activators, we observed a striking pattern: TEs were predominantly activated in normal IMR90 cells but repressed in HCT116 cancer cells. Analysis of 24 transcriptomes and 10 cistromes further confirmed this trend, distinguishing normal from cancer cell regulation. At the family level, normal cells showed broad TE upregulation, whereas cancer cells exhibited selective repression of Alu and LINE elements, with weaker effects on endogenous retroviruses. These findings provide the first comprehensive, locus-specific view of p53-mediated TE regulation, highlighting distinct chromatin-dependent dynamics in normal and cancer cells.

bioinformatics↗

Interfamily co-transfer of sensor and helper NLRs extends immune receptor functionality between angiosperms

Plant nucleotide-binding, leucine-rich repeat (NLR) immune receptors recognize pathogen effectors and activate defense. NLR genes can be non-functional in distantly related plants (restricted taxonomic functionality, RTF). Here, we enable Solanaceae NLR gene function in rice, soybean and Arabidopsis by co-delivering sensor NLR genes with their cognate NRC-type helper NLRs. In soybean protoplasts and in Arabidopsis plants, Solanum americanum Rpi-amr1, Rpi-amr3 and pepper Bs2 sensor NLRs confer cognate effector responsiveness if co-expressed with NRC helper NLRs. Rice carrying pepper Bs2 and NRCs recognizes the conserved effector, AvrBs2, and resists an important pathogen, Xanthomonas oryzae pv. oryzicola for which no resistance gene is available in rice. Rice lines carrying sensor and helper NLR genes otherwise resemble wild-type, with unaltered basal resistance or field fitness. Thus, interfamily co-transfer of sensor and helper NLRs can broaden utility of sensor NLRs, extending the tools available to control diseases of rice, soybean, Brassicas and other crops.

plant biology↗

Histone N-tails modulate sequence-specific positioning of nucleosomes

The precise mechanisms governing sequence-dependent positioning of nucleosomes on DNA remain unknown in detail. Existing algorithms, taking into account the sequence-dependent deformability of DNA and its interactions with the histone globular domains, predict rotational setting of only 65% of human nucleosomes mapped in vivo. To uncover novel factors responsible for the nucleosome positioning, we analyzed potential involvement of the histone N-tails in this process. To this aim, we reconstituted the H2A/H4 N-tailless nucleosomes on human BRCA1 DNA ([~]100 kb) and compared their positions and sequences with those of the wild-type nucleosomes. In the case of H2A tailless nucleosomes, the AT content of DNA sequences is changed locally at superhelical location (SHL) {+/-}4, while maintaining the same rotational setting as their wild-type counterparts. Conversely, the H4 tailless nucleosomes display widespread changes of the AT content near SHL {+/-}1 and SHL {+/-}2, where the H4 N-tails interact with DNA. Furthermore, a substantial number of H4 tailless nucleosomes exhibit rotational setting opposite to that of the wild-type nucleosomes. Thus, our findings strongly suggest that the histone N-tails are operative in selection of nucleosome positions, which may have wide-ranging implications for epigenetic modulation of chromatin states.

molecular biology↗

Attenuating amyloid-beta pathology in mice with in situ programmed astrocytes

Astrocytes are abundant cells in the central nervous system that provide trophic support for neurons and clear detrimental factors, such as A{beta} oligomers (A{beta}Os). However, in the brains of Alzheimers disease (AD) patients, astrocytes lose these physiological functions. Here, we genetically engineered astrocytes with an anti-A{beta}O chimeric antigen receptor (CAR), constructed by replacing the antigen-binding domain of MerTK with an A{beta}O-specific single-chain variable fragment, to direct their phagocytic activity against A{beta}Os. CAR-engineered astrocytes (CAR-As) showed significantly enhanced phagocytosis of A{beta}Os due to effective activation of Rac1, Cdc42 and RhoA and markedly decreased release of pro-inflammatory cytokines due to inhibition of the NF-{kappa}B and cytokine receptor signalling pathways. Consistently, in situ CAR-As markedly ameliorated the cognitive deficits of APP/PS1 transgenic mice possibly by clearing A{beta}Os and creating a non-inflammatory microenvironment for neuronal survival and the restoration of microglia to a healthy phenotype. Our present study is the first to introduce a CAR-A-based therapy, validate its feasibility and effectiveness, and highlight its potential application for the treatment of AD and other brain disorders.

neuroscience↗

SAKit: an all-in-one analysis pipeline for identifying novel protein caused by variant events at genomic and transcriptic level

SummaryGenetic modifications that cause pivotal protein inactivation or abnormal activation may lead to cell signaling pathway change or even dysfunction, resulting in cancer and other diseases. In turn, dysfunction will further produce "novel proteins" that do not exist in the canonical human proteome. Identification of novel proteins is meaningful for identifying promising drug targets and developing new therapies. In recent years, several tools have been developed for identifying DNA or RNA variants with the extensive application of nucleotide sequencing technology. However, these tools mainly focus on point mutation and have limited performance in identifying large-scale variants as well as the integration of mutations. Here we developed a hybrid Sequencing Analysis bioinformatic pipeline by integrating all relevant detection Kits(SAKit): this pipeline fully integrates all variants at the genomic and transcriptomic level that may lead to the production of novel proteins defined as proteins with novel sequences compare to all reference sequences by comprehensively analyzing the long and short reads. The analysis results of SAKit demonstrate that large-scale mutations have more contribution to the production of novel proteins than point mutations, and long-read sequencing has more advantages in large-scale mutation detection. Availability and implementationSAKit is freely available on docker image (https://hub.docker.com/repository/docker/therarna/sakit), which is mainly implemented within a Snakemake framework in Python language.

bioinformatics↗

Epigenetic modifications mediate cultivar-specific root development and metabolic adaptation to nitrogen availability in wheat

The breeding of crops with improved nitrogen use efficiency (NUE) is crucial for sustainable agriculture. However, the role of epigenetic modification in the regulation of cultivar-specific responses to low nitrogen (LN) constraint is not well understood. Here, we analyzed the chromatin landscapes in roots, leaves, and seeds in two wheat cultivars (KN9204 and J411) that differ radically in NUE under normal and nitrogen-limited conditions. Transcriptional regulatory chromatin regions exhibited a clear cultivar-specificity between KN9204 and J411. Cultivar-specific regulation of nitrogen metabolism genes (NMGs) is linked to variation in histone modification levels, rather than differences in DNA sequence. Cultivar-specific histone modification regions were found to contribute to the genetic regulation of NUE-related traits, such as QTL locus of maximum root length of qMRL-7B. Furthermore, LN-induced H3K27ac and H3K27me3 dynamics enhanced root growth more in KN9204, while strengthened the nitrogen uptake system more in J411. Evidence from histone deacetylase inhibitor treatment and transgenic plants with loss-of-function of the H3K27me3 methyltransferase further showed that changes in epigenetic modifications can alter the strategy for root development and nitrogen uptake in response to LN constraint. Taken together, the results of our study highlight the importance of epigenetic regulation in mediating cultivar-specific root development and metabolic adaptation to LN in wheat.

plant biology↗

3D co-culture of macrophages and fibroblasts in a sessile drop chip for unveiling the role of macrophages in skin wound-healing

Three-dimension (3D) cell co-cultural spheroids exhibit enhanced cellular functions and they can mirror in-vivo microenvironments. Herein, a sessile drop chip was developed to construct 3D spheroids for mirroring the wound healing microenvironment. The sessile drop chip holds the superhydrophobic surface of each microwell which can facilitate cell suspensions transfer to spheroids through the offset of surface tension and gravity, and each microwell has a cylinder hole that offers adequate oxygen to spheroids. It was demonstrated that the 3T3 fibroblast spheroid and the 3T3 fibroblast/M2-type macrophage co-culture spheroid can be formed and remained the physiological activity within nine days. 3D morphology of spheroids was reconstructed using the transparent processing technology and Z-stack function of confocal microscopy. Characteristics of proliferation and differentiation were analyzed by using nano antibody-based 3D immunostaining assay. Results revealed that M2-type macrophages can promote the proliferation and differentiation of the 3T3 fibroblast spheroid. This study presented a novel affordable platform for developing 3D spheroids and provides a 3D model for investigating the macrophages-associated wound healing microenvironment.

bioengineering↗

Boosting wheat functional genomics via indexed EMS mutant library of KN9204

A better understanding of wheat functional genomics could facilitate the targeted breeding for agronomic traits improvement and environmental adaptation. With the release of reference genomes and extensive re-sequencing data of wheat and relatives, wheat functional genomics enters a new era. However, limited transformation efficiency in wheat hampers in-depth gene functional study and genetic manipulation for breeding. Here, we generated an EMS mutagenesis library of KN9204, a widely grown elite wheat variety in northern China, with available reference genome, transcriptome, and epigenome of various tissues. The library harbors enormous developmental diversity covering important tissues and transition stages. Exome capture sequencing of 2,090 mutant lines, with probes designed by KN9204 genome, revealed that 98.79% of coding genes have mutations and 1,383 EMS-type SNPs per line averagely. Novel allelic variations for important agronomic trait-related genes, such as Rht-D1, Q, TaTB1, and WFZP, were identified. We tested 100 lines with severe mutations in 80 NAC TFs under drought and salinity stresses, and found 13 lines with altered sensitivity. Three lines were further analyzed for the regulation insight of NAC TFs in stress response by combing transcriptome and available chromatin accessibility data. Hundreds of direct targets of NAC with altered transcriptional pattern in mutant lines under salt or drought stress induction were identified, including SNAC1, DREB2B, CML16 and ZFP182, knowing factors in abiotic stresses response. Thus, we have generated and indexed KN9204 EMS mutant library which would facilitate functional genomics study and provide resources for genetic manipulation in wheat.

plant biology↗

To praise or to blame? Neural signals predict divergent responses to moral hypocrisy.

Moral hypocrisy is common in society and could be discouraged if observers always respond negatively. Understanding the observers responses to moral hypocrisy is critical for promoting genuine morality. This study took the perspective from the observers and compared their behavioral and neural responses to moral hypocrisy versus clear moral/immoral acts. Behaviorally, we found that claiming to help but avoiding the cost of help (i.e., moral hypocrisy) was endorsed as more moral than rejecting to help and even received monetary praise from 40% of observers. Neurally, moral hypocrisy versus clear moral acts elicited reduced responses in the reward system (e.g., ventromedial prefrontal cortex) and increased responses in regions responsible for disgust (e.g., anterior insula). The neural signals together with the interplay to the mentalizing network (e.g., temporoparietal junction) predicted divergent responses, even five months later. Our findings provide behavioral and neural accounts of how hypocrisy is perceived and why it prevails. Significance StatementO_LIFrom the perspective of a third-party observer, this study showed that moral hypocrisy is indeed deceptive and induces observers divergent responses of praise or blame. C_LIO_LIClaiming to help but avoiding the cost of help (i.e., moral hypocrisy) was considered more moral than rejecting to help and even received monetary praise from 40% of observers. C_LIO_LIUsing fMRI, this study revealed that the divergent behavioral responses to moral hypocrisy could be predicted and classified by the activations of the reward system (e.g., ventromedial prefrontal cortex) and regions responsible for disgust (e.g., anterior insula) as well as the functional connectivity with the mentalizing network (e.g., right temporoparietal junction), even five months later. C_LI

neuroscience↗

Cryo-EM structures reveal the activation and substrate recognition mechanism of human enteropeptidase

The enteropeptidase (EP) initiates the intestinal digestion by proteolytic processing of trypsinogen, generating catalytic active trypsin. The dysfunction of EP will cause a series of pancreatic diseases, the most severe of which is acute necrotizing pancreatitis. However, the molecular mechanism of EP activation and substrate recognition remain elusive due to the lack of structural information, hampering the structure-based research of EP and even further EP-targeted drug design. Here we report cryo-EM structures of human EP in multiple states, covering the functional cycle spanning from inactive to active state and eventually to the substrate binding state, with the inactive core region reached an atomic 2.7-[A]-resolution. The heavy chain of EP exhibits a clamping configuration with the CUB2 domain serving for substrate recognition. The N-terminus of light chain induces the surface loop remodeling from inactive to active conformation, resulting in a highly dynamic and active EP. Then the heavy chain performs like a hinge to ensure the flexibility of light chain for substrate recruitment and subsequent cleavage. Our study provides structural insights of EP remodeling and heavy chain dynamics while performing enzymatic function, facilitating our understanding of the pathogenies of EP-related pancreatitis and the EP-targeted treatment of pancreatitis.

cell biology↗

The brassinosteroid biosynthesis gene TaD11-2A controls grain size and its elite haplotype improves wheat grain yields

Brassinosteroids (BRs) control many important agronomic traits, therefore the manipulation of BR components could improve crop productivity and performance. However, the potential effects of BR-related genes on yield-related traits and stress tolerance in wheat (Triticum aestivum L.) remain poorly understood. Here, we identified TaD11 genes in wheat (rice D11 orthologs) that encoded enzymes involved in BR biosynthesis. TaD11 genes were highly expressed in roots (Zadoks scale: Z11) and grains (Z75), while expression was significantly suppressed by exogenous BR (24-epiBL). Ectopic expression of TaD11-2A rescued the abnormal panicle structure and plant height (PH) of the cpb1 mutant, and also increased endogenous BR levels, resulting in improved grain yields and grain quality in rice. Natural variations in TaD11-2A were associated with significant differences in yield-related traits, including PH, grain width (GW), 1000-grain weight (TGW), and grain yield per plant (GYPP), and its favorable haplotype, TaD11-2A-HapI was subjected to positive selection during wheat breeding. Additionally, TaD11-2A influenced root length and salt tolerance in rice and wheat at seedling stages. These results indicated the important role of BR TaD11 biosynthetic genes in controlling grain size and root length, and also highlighted their potential in the molecular biological analysis of wheat. HighlightThe brassinosteroid biosynthesis gene TaD11-2A regulates grain size and root length and its haplotype favorably improves grain yields and salt tolerance in wheat.

plant biology↗

BOS1 is a positive regulator of wounding induced cell death and plant susceptibility to Botrytis

Programmed cell death (PCD) is required for many aspects of plant biology, including stress responses, immunity, and plant development including root and flower development. Our understanding of PCD regulation is incomplete, especially concerning regulators involved in multiple divergent processes. The botrytis-suscetible1 (bos1) mutant is one of the genotypes most susceptible to Botrytis cinerea (Botrytis) and has revealed the role of BOS1 in cell death propagation during plant responses to wounding. The bos1-1 allele harbours a T-DNA located in the 5UTR upstream from the start codon that results in elevated BOS1 transcript levels. Here, we resequenced the bos1-1 genome and found a MAS promoter at the ends of the T-DNAs. Expression of the BOS1 gene under control of the MAS promoter conferred the characteristic bos1-1 Botrytis- sensitivity and wounding phenotypes in wildtype plants. We used Crispr-Cas9 to create new bos1 alleles that disrupt exons. These lines lacked the typical bos1-1 wounding and Botrytis phenotypes, but exhibited reduced fertility, as previously observed in other bos1 T-DNA alleles. With multiple overexpression lines of BOS1, we demonstrate that BOS1 is involved in regulation of cell death propagation in a dosage dependent manner. Our data support that bos1-1 is a gain-of-function mutant and that BOS1 acts as a positive regulator of wounding and Botrytis-induced PCD. Taken together these finding suggest that BOS1 function in both fertility and Botrytis response could be unified under cell death control.

plant biology↗

Dissecting the subtropical adaptation traits and cuticle synthesis pathways via the genome of the subtropical blueberry Vaccinium darrowii

Vaccinium darrowii is a subtropical wild blueberry species, which was used to breed economically important southern highbush cultivars. The adaptation traits of V. darrowii to subtropical climate would provide valuable information for breeding blueberry and perhaps other plants, especially against the background of global warming. Here, we assembled the V. darrowii genome into 12 pseudochoromosomes using Oxford Nanopore long reads complemented with Hi-C scaffolding technologies, and predicted 41 815 genes using RNAseq evidence. Syntenic analysis across three Vaccinium species revealed a highly conserved genome structure, with the highest collinearity between V. darrowii and V. corymbosum. This conserved genome structure may explain the high fertilization during crossbreeding between V. darrowii and other blueberry cultivars. Gene expansion and tandem duplication analysis indicated possible roles of defense and flowering associated genes in adaptation of V. darrowii to the subtropics. The possible SOC1 genes in V. darrowii were identified with phylogeny and expression analysis. Blueberries are covered in a thick cuticle layer and contain anthocyanins, which confer their powdery blue color. Using RNA-sequencing, the cuticle biosynthesis pathways of Vaccinium species were delineated here in V. darrowii. This result could serve as a reference for breeding berries with customer-desired colors. The V. darrowii reference genome, together with the unique traits of this species, including diploid genome, short vegetative phase, and high compatibility in hybridization with other blueberries, make V. darrowii a potential research model for blueberry species.

plant biology↗

Case study of a rhizosphere microbiome assay on a bamboo rhizome with excessive shoots

Young Moso bamboo shoots are a very popular seasonal food. Bamboo is an important source of income for farmers and the value for cultivation has recently been estimated to $30,000 per hectare. A rare and valuable phenomenon has recently appeared where dozens of adjacent buds within a single Moso bamboo rhizome have grown into shoots. Due to its rarity, this phenomenon, which is of practical importance for the production of edible shoots, has not been scientifically studied. We report the occurrence of a rhizome with 18 shoots, of which the microbiome were analyzed, using rhizomes having one or no shoots as controls. The community of prokaryotes, but not fungi, correlated with the shoot numbers. Burkholderia was the most abundant genus, which negatively correlated with rhizome shoot number, while Clostridia and Ktedonobacteria positively correlated with many shoots. Two Burkholderia strains were isolated and their plant-growth promoting activity was tested. The isolated Burkholderia strains attenuated the growth of bamboo seedlings. Analysis of collected events of enhanced shoot production in China showed no evidence that enhanced shoot development was heritable. Overall, our data provides a firsthand study on excessive shoot development of bamboo.

plant biology↗

The sensitivity of third party punishment to the framing effect and its brain mechanism

People as third-party observers, without direct self-interest, may punish norm violators to maintain social norms. However, third-party judgment and the follow-up punishment might be susceptible to the way we frame (i.e., verbally describe) a norm violation. We conducted a behavioral and a neuroimaging experiment to investigate the above phenomenon, which we call "third-party framing effect." In these experiments, participants observed an anonymous player A decided whether to retain her/his economic benefit while exposing player B to a risk of physical pain (described as "harming others" in one condition and "not helping others" in the other condition), then they had a chance to punish player A at their own cost. Participants were more willing to execute third-party punishment under the harm frame compared to the help frame, manifesting as a framing effect. Self-reported moral outrage toward player A mediated the relationship between empathy toward player B and the framing effect size. Correspondingly, the insula (possibly related to empathy) and cerebellum (possibly related to anger) were activated more strongly under the harm frame than the help frame. Functional connectivity between these regions showed strongest weight when predicting the framing effect size. These findings shed light on the psychological and neural mechanisms of the third-party framing effect. Graphic abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=57 SRC="FIGDIR/small/426181v1_ufig1.gif" ALT="Figure 1"> View larger version (18K): org.highwire.dtl.DTLVardef@f4dd4dorg.highwire.dtl.DTLVardef@1eceed3org.highwire.dtl.DTLVardef@3360a8org.highwire.dtl.DTLVardef@10ed26b_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗

Species packing and the latitudinal gradient in local beta-diversity

The decline in species richness at higher latitudes is among the most fundamental patterns in ecology. Whether changes in species composition across space (beta-diversity) contribute to this gradient of overall species richness (gamma-diversity) remains hotly debated. Previous studies that failed to resolve the issue suffered from a well-known tendency for small samples in areas with high gamma-diversity to have inflated measures of beta-diversity. Here, we provide here a novel analytical test, using beta-diversity metrics that correct the gamma-diversity and sampling biases, to compare beta-diversity and species packing across a latitudinal gradient in tree species richness of 21 large forest plots along a large environmental gradient in East Asia. We demonstrate that after accounting for topography and correcting the gamma-diversity bias, tropical forests still have higher beta-diversity than temperate analogs. This suggests that beta-diversity contributes to the latitudinal species richness gradient as a component of gamma-diversity. Moreover, both niche specialization and niche marginality (a measure of niche spacing along an environmental gradient) also increase towards the equator, after controlling for the effect of topographic heterogeneity. This supports the joint importance of tighter species packing and larger niche space in tropical forests while also demonstrating the importance of local processes in controlling beta-diversity.

ecology↗