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Yang, X.

Publications and source records attributed to Yang, X..

At least 415 records · Page 23Linked to original sources

Molecular regulation of Bna1205ams1 required for male fertility and development of a recessive genic male-sterility system in Brassica napus

Through the comprehensive use of two pollination control systems of cytoplasmic male sterility (CMS) and genic male sterility (GMS), the rapeseed yield was increased by more than 20%. However, more hybrid production systems and detailed mechanisms underlying male sterility are required. Here, we reported a novel two-line hybrid production system of 1205A for GMS and also investigated the underlying mechanism for male sterility. Five co-segregated kompetitive allele specific PCR (KASP) markers were developed and validated, which could be used for transferring the male sterility trait into external B. napus breeding lines and developing further two-line hybrid production systems of GMS. Inheritance studies detected one gene locus of Bna1205ams1 for regulating the male sterility of 1205A. As a potential candidate gene of Bna1205ams1, BnaC03g27700D was fine mapped and narrowed down to a 181.47 kb region on chrC03 and validated by functional analysis. The mutation of BnaC03g27700D in 1205A resulted in large metabolic fluctuations, most of which were involved in aborted tapetal PCD, which could lead to reduced pollen fertility with abnormal pollen exine. The developed new GMS line of 1205AB provided us with the opportunity to identify a new male sterility gene of BnaC03g27700D in B. napus. The study of BnaC03g27700D aims to renew the annotation of the gene and provide new resources for basic research on the genetic control of male sterility.

molecular biology↗

PathEX: Make Good Choice for Whole Slide Image Extraction

BackgroundThe tile-based approach has been widely used for slide-level predictions in whole slide image (WSI) analysis. However, the irregular shapes and variable dimensions of tumor regions pose challenges for the process. To address this issue, we proposed PathEX, a framework that integrates intersection over tile (IoT) and background over tile (BoT) algorithms to extract tile images around boundaries of annotated regions while excluding the blank tile images within these regions. MethodsWe developed PathEX, which incorporated IoT and BoT into tile extraction, for training a classification model in CAM (239 WSIs) and PAIP (40 WSIs) datasets. By adjusting the IoT and BoT parameters, we generated eight training sets and corresponding models for each dataset. The performance of PathEX was assessed on the testing set comprising 13,076 tile images from 48 WSIs of CAM dataset and 6,391 tile images from 10 WSIs of PAIP dataset. ResultsPathEX could extract tile images around boundaries of annotated region differently by adjusting the IoT parameter, while exclusion of blank tile images within annotated regions achieved by setting the BoT parameter. As adjusting IoT from 0.1 to 1.0, and 1 - BoT from 0.0 to 0.5, we got 8 train sets. Experimentation revealed that set C demonstrates potential as the most optimal candidate. Nevertheless, a combination of IoT values ranging from 0.2 to 0.5 and 1-BoT values ranging from 0.2 to 0.5 also yielded favorable outcomes. ConclusionsIn this study, we proposed PathEX, a framework that integrates IoT and BoT algorithms for tile image extraction at the boundaries of annotated regions while excluding blank tiles within these regions. Researchers can conveniently set the thresholds for IoT and BoT to facilitate tile image extraction in their own studies. The insights gained from this research provide valuable guidance for tile image extraction in digital pathology applications.

pathology↗

Biallelic pathogenic variants in DNAH3 cause male infertility in humans and mice

Axonemal protein complexes, including the outer and inner dynein arms (ODA/IDA), are highly ordered structures of the sperm flagella that drive sperm motility. Deficiencies in several axonemal proteins have been associated with male infertility, which is characterized by asthenozoospermia or asthenoteratozoospermia. Dynein axonemal heavy chain 3 (DNAH3) resides in the IDA and is highly expressed in the testis. However, the relationship between DNAH3 and male infertility is still unclear. Herein, we identified biallelic variants of DNAH3 in four unrelated Han Chinese infertile men with asthenoteratozoospermia through whole-exome sequencing (WES). These variants contributed to deficient DNAH3 expression in the patients sperm flagella. Importantly, the patients represented the anomalous sperm flagellar morphology, and the flagellar ultrastructure was severely disrupted. Intriguingly, Dnah3 knockout (KO) male mice were also infertile, especially showing the severe reduction in sperm movement with the abnormal IDA and mitochondrion structure. Mechanically, nonfunctional DNAH3 expression resulted in decreased expression of IDA-associated proteins in the spermatozoa flagella of patients and KO mice, including DNAH1, DNAH6, and DNALI1, the deletion of which has been involved in disruption of sperm motility. Moreover, the infertility of patients with DNAH3 variants and Dnah3 KO mice could be rescued by intracytoplasmic sperm injection (ICSI) treatment. Our findings indicated that DNAH3 is a novel pathogenic gene for asthenoteratozoospermia and may further contribute to the diagnosis, genetic counseling, and prognosis of male infertility.

genetics↗

Feed-forward stimulation of CAMK2 by the oncogenic pseudokinase PEAK1 generates a therapeutically "actionable" signalling axis in triple negative breast cancer

The PEAK family of pseudokinases, comprising PEAK1-3, are signalling scaffolds that play oncogenic roles in several poor prognosis human cancers, including triple negative breast cancer (TNBC). However, therapeutic targeting of pseudokinases is challenging due to their lack of catalytic activity. To address this, we screened for PEAK1 effectors by affinity purification and mass spectrometry, identifying calcium/calmodulin-dependent protein kinase 2 (CAMK2)D and CAMK2G. PEAK1 promoted CAMK2D/G activation in TNBC cells via a novel feed-forward mechanism involving PEAK1/PLC{gamma}1/Ca2+ signalling and direct binding via a consensus CAMK2 interaction motif in the PEAK1 N-terminus. In turn, CAMK2 phosphorylated PEAK1 to enhance association with PEAK2, which is critical for PEAK1 oncogenic signalling. To achieve pharmacologic targeting of PEAK1/CAMK2, we repurposed RA306, a second generation CAMK2 inhibitor under pre-clinical development for treatment of cardiovascular disease. RA306 demonstrated on-target activity against CAMK2 in TNBC cells and inhibited PEAK1-enhanced migration and invasion in vitro. Moreover, RA306 significantly attenuated TNBC xenograft growth and blocked metastasis in a manner mirrored by CRISPR-mediated PEAK1 ablation. Overall, these studies establish PEAK1 as a critical cell signalling nexus, identify a novel mechanism for regulation of Ca2+ signalling and its integration with tyrosine kinase signals, and identify CAMK2 as a therapeutically actionable target downstream of PEAK1.

cancer biology↗

Controlling for polygenic genetic confounding in epidemiologic association studies

Epidemiologic associations estimated from observational data are often confounded by genetics due to pervasive pleiotropy among complex traits. Many studies either neglect genetic confounding altogether or rely on adjusting for polygenic scores (PGS) in regression analysis. In this study, we unveil that the commonly employed PGS approach is inadequate for removing genetic confounding due to measurement error and model misspecification. To tackle this challenge, we introduce PENGUIN, a principled framework for polygenic genetic confounding control based on variance component estimation. In addition, we present extensions of this approach that can estimate genetically-unconfounded associations using GWAS summary statistics alone as input and between multiple generations of study samples. Through simulations, we demonstrate superior statistical properties of PENGUIN compared to the existing approaches. Applying our method to multiple population cohorts, we reveal and remove substantial genetic confounding in the associations of educational attainment with various complex traits and between parental and offspring education. Our results show that PENGUIN is an effective solution for genetic confounding control in observational data analysis with broad applications in future epidemiologic association studies.

genetics↗

ATP13A1 engages GET3 to facilitate substrate-specific translocation

Proper localization of proteins to their final destinations is crucial for preserving cellular structure and functions. The interpretation and sorting of highly variable targeting sequences in secreted and membrane proteins, however, pose a challenge in achieving precise localization within specific secretory apparatus. In this study, we demonstrate that atypical signal sequences characterized by high hydrophobicity and/or the absence of characteristic charges undergo targeting to the endoplasmic reticulum (ER) in a reverse orientation, followed by partial cleavage. The P5A- ATPase ATP13A1 recognizes the cleaved signal sequence and dislocates it to the targeting factor GET3, subsequently engaging SEC61 for further translocation. Our findings unveil a comprehensive translocation pathway that operates in a substrate- specific manner, ensuring both high efficiency and fidelity in the protein subcellular localization.

biochemistry↗

Sarbecovirus RBD indels and specific residues dictating ACE2 multi-species adaptiveness

Sarbecoviruses exhibit varying abilities in using angiotensin-converting enzyme 2 (ACE2) receptor1-3. However, a comprehensive understanding of their multi-species ACE2 adaptiveness and the underlying mechanism remains elusive, particularly for many sarbecoviruses with various receptor binding motif (RBM) insertions/deletions (indels)4-11. Here, we analyzed RBM sequences from 268 sarbecoviruses categorized into four RBM indel types. We extensively examined the capability of 14 representative sarbecoviruses and their derivatives in using ACE2 orthologues from 51 bats and five non-bat mammals. We revealed that most sarbecoviruses with longer RBMs (type-I), present broad ACE2 tropism, whereas viruses with single deletions in Region 1 (type-II) or Region 2 (type-III) generally exhibit narrow ACE2 tropism, typically favoring their hosts ACE2. Sarbecoviruses with double region deletions (type-IV) exhibit a complete loss of ACE2 usage. Subsequent investigations unveiled that both loop deletions and critical RBM residues significantly impact multi-species ACE2 tropism in different ways. Additionally, fine mapping based on type-IV sarbecoviruses elucidated the role of several clade-specific residues, both within and outside the RBM, in restricting ACE2 usage. Lastly, we hypothesized the evolution of sarbecovirus RBM indels and illustrated how loop length, disulfide, and adaptive mutations shape their multi-species ACE2 adaptiveness. This study provides profound insights into the mechanisms governing ACE2 usage and spillover risks of sarbecoviruses.

microbiology↗

Human Motor Cortex Encodes Complex Handwriting Through a Sequence of Primitive Neural States

How the human motor cortex (MC) orchestrates sophisticated fine movements such as handwriting remains a puzzle1-3. Here, we investigate this question through Utah array recordings from human MC hand knob, during imagined handwriting of Chinese characters (306 characters tested, 6.3 {+/-} 2.0 strokes per character). We find MC programs the writing of complicated characters by sequencing a small set of primitive states: The directional tuning of motor neurons remains stable within each primitive state but strongly varies across states. Furthermore, the occurrence of a primitive state is encoded by a separate set of neurons not directly involved in movement control. By automatically identifying the primitive states and corresponding neuronal tuning properties, we can reconstruct a recognizable writing trajectory for each character (84% improvement in reconstruction accuracy compared with baseline). Our findings unveil that skilled, sophisticated movements are decomposed into a sequence of primitive movements that are programmed through state-specific neural configurations, and this hierarchical control mechanism sheds new light on the design of high-performance brain-computer interfaces.

neuroscience↗

Development of a LRRC15-Targeted Radio-Immunotheranostic Approach to Deplete Pro-tumorigenic Mechanisms and Immunotherapy Resistance

Leucine-rich repeat containing 15 (LRRC15) has emerged as an attractive biomarker and target for cancer therapy. We have developed a humanized monoclonal antibody (mAb), DUNP19, that specifically binds to a phylogenetically conserved LRRC15 epitope and is internalized by target-expressing cancer and stromal cells. In xenograft mouse models, Lutetium-177 labeled DUNP19 ([177Lu]-DUNP19) enables non-invasive imaging and precise radiotherapy to LRRC15-expressing cancer cells and murine cancer-associated fibroblasts (CAFs), halting tumor progression and prolonging survival with minimal toxicity. Transcriptomic analyses of [177Lu]-DUNP19-treated tumors reveal a loss of pro-tumorigenic mechanisms, including a transforming growth factor beta (TGF{beta})-driven and LRRC15+ signature associated with immunotherapy resistance. Together, these results demonstrate that radio-theranostic targeting of LRRC15 with DUNP19 is a compelling precision medicine platform for image-guided diagnosis, eradication, and reprogramming of LRRC15+ tumor tissue that drives immuno-resistance and aggressive disease. SIGNIFICANCEWe introduce a pioneering LRRC15-guided radio-theranostic approach integrating clinical imaging and radioimmunotherapy. Our strategy utilizes a mAb, DUNP19, to target LRRC15-expressing cancer cells and fibroblasts, demonstrating significant tumor reduction, prolonged survival, and reversal of TGF{beta}-driven treatment resistance. This approach offers a promising strategy for improving outcomes in aggressive cancers.

pharmacology and toxicology↗

Mitochondrial fission surveillance is coupled to Caenorhabditis elegans DNA and chromosome segregation integrity

Mitochondrial fission and fusion are tightly regulated to specify mitochondrial abundance, localization, and arrangement during cell division as well as in the diverse differentiated cell types and physiological states. However, the regulatory pathways for such mitochondrial dynamics are less explored than the mitochondrial fission and fusion components. Here we report a large-scale screen for genes that regulate mitochondrial fission. Mitochondrial fission defects cause a characteristic asymmetric fluorescent pattern in embryos carrying mitochondrial stress reporter genes. Using this asymmetric activation, we performed RNAi screens that identified 3 kinase genes from a [~]500-kinase library and another 11 genes from 3,300 random genes that function in mitochondrial fission. Many of these identified genes play roles in chromosome segregation. We find that chromosome missegregation and genome instability lead to dysregulation of mitochondrial fission in a manner independent of Drp-1. ATL-1, the C. elegans ATR orthologue, plays a protective role in alleviating the mitochondrial fission defect caused by chromosome missegregation. This establishes a screening paradigm for identifying mitochondrial fission regulators which reveals the role of ATR in surveilling mitochondrial fission to mitigate dysregulation caused by improper chromosome segregation.

cell biology↗

Disease resistance of Brassica juncea to Sclerotinia sclerotiorum is established through the induction of indole glucosinolate biosynthesis

Sclerotinia stem rot (SSR), caused by Sclerotinia sclerotiorum, is the main disease threat to oilseeds in Brassiceae, causing significant yield losses and reduction in oil content and quality. The studies on S. sclerotiorum require a great focus and extensive research on B. juncea compared to those on B. napus and B. oleracea. Transcriptome analysis revealed a large number of defense-related genes and response processes in B. napus and B. oleracea. However, similarities and differences in the defense responses to S. sclerotiorum on B. juncea are rarely reported. In the present study, we reported a B. juncea breeding line of H83 with high S. sclerotiorum resistance, which was used for transcriptome analysis compared to L36 with low resistance. A novel regulatory network was proposed to defend against S. sclerotiorum invasion in B. juncea. Upon infection of S. sclerotiorum, a series of auxin and MAPK signaling pathways were initiated within 12 h, and then defenses were activated to restrict the development and spread of S. sclerotiorum by inducing the massive synthesis of indole glucosinolates after 24 h. Twelve hub genes involved in the network were identified by the weighted gene co-expression network (WGCNA), which are involved in plant-pathogen interaction, signaling pathway genes, indole glucosinolate biosynthesis and cell wall formation. The hub genes were further validated by qRT-PCR. The research revealed a new resistant line of H83 against S. sclerotiorum and a different regulatory network in B. juncea, which would be beneficial for the future effective breeding of Sclerotinia-resistant varieties.

plant biology↗

A general platform for targeting MHC-II antigens via a single loop

Class-II major histocompatibility complexes (MHC-IIs) are central to the communications between CD4+ T cells and antigen presenting cells (APCs), but intrinsic structural features associated with MHC-II make it difficult to develop a general targeting system with high affinity and antigen specificity. Here, we introduce a protein platform, Targeted Recognition of Antigen-MHC Complex Reporter for MHC-II (TRACeR-II), to enable the rapid development of peptide-specific MHC-II binders. TRACeR-II has a small helical bundle scaffold and uses an unconventional mechanism to recognize antigens via a single loop. This unique antigen-recognition mechanism renders this platform highly versatile and amenable to direct structural modeling of the interactions with the antigen. We demonstrate that TRACeR-II binders can be rapidly evolved across multiple alleles, while computational protein design can produce specific binding sequences for a SARS-CoV-2 peptide of unknown complex structure. TRACeR-II sheds light on a simple and straightforward approach to address the MHC peptide targeting challenge, without relying on combinatorial selection on complementarity determining region (CDR) loops. It presents a promising basis for further exploration in immune response modulation as well as a broad range of theragnostic applications.

bioengineering↗

Centromere landscapes resolved from hundreds of human genomes

High-fidelity (HiFi) sequencing has facilitated the assembly and analysis of the most repetitive region of the genome, the centromere. Nevertheless, our current understanding of human centromeres draws from a relatively small number of telomere-to-telomere assemblies, and so has not yet captured its full diversity. In this study, we investigated the genomic diversity of human centromere higher order repeats (HORs) using both HiFi reads and haplotype-resolved assemblies from hundreds of samples drawn from ongoing pangenome-sequencing projects and reprocessed using a novel HOR annotation pipeline, HiCAT-human. We use this wealth of data to provide a global survey of the centromeric HOR landscape, in particular finding that 23 HORs exhibited significant copy number variability between populations. We detected three centromere genotypes with imbalance population frequencies on each of chromosome 5, 8 and 17. An inter-assembly comparison of HOR loci further revealed that while HOR array structures are diverse, they nevertheless tend to form a number of specific landscapes, each exhibiting different levels of HOR subunit expansion and possibly reflecting a cyclical evolutionary transition from homogeneous to nested structures and back.

genomics↗

XKidneyOnco: An Explainable Framework to Classify Renal Oncocytoma and Chromophobe Renal Cell Carcinoma with a Small Sample Size

Renal oncocytoma and chromophobe renal cell carcinoma are two kidney cancer types that present a diagnostic challenge to pathologists and other clinicians due to their microscopic similarities. While RO is a benign renal neoplasm, ChRCC is considered malignant. Therefore, the differentiation between the two is crucial. In this study, we introduce an explainable framework to accurately differentiate ChRCC from RO, histologically. Our approach examined H&E-stained images of 656 ChRCC and 720 RO, and achieved a diagnostic accuracy of 88.2%, the sensitivity of 87%, and 100% specificity for explainable AI, which either outperforms or operate on par with convolutional neural network (CNN) models. Besides, we enrolled 44 pathology experts (including pathologists and pathology trainees) to differentiate the two tumors. The average accuracy of pathologists was 73%, which is 15.2% lower than our framework. These results indicate that the combination of human expert along with explainable AI achieve higher accuracy in differentiating the two tumors, while it reduces the workload of experts and offers the desired explainability for the medical experts.

pathology↗

Transcranial Photobiomodulation on the Left Prefrontal Cortex Enhances Mandarin Chinese L1 and L2 Complex Sentence Processing Performances

This study investigated the causal effect of transcranial photobiomodulation (tPBM) over the left prefrontal cortex (LPFC) on syntactically complex Mandarin Chinese first language (L1) and second language (L2) sentence processing performances. Two (L1 and L2) groups of participants (thirty per group) were recruited to receive the double-blind, sham-controlled tPBM intervention, followed by the sentence processing, the verbal working memory (WM), and the visual WM tasks. Results revealed a consistent pattern for both groups: (a) tPBM enhanced sentence processing performance but not verbal WM and visual WM performance; (b) Participants with lower sentence processing performances under sham tPBM benefited more from active tPBM. Taken together, the current study substantiated that tPBM enhanced L1 and L2 sentence processing ability directly without verbal WM interference, and would serve as a promising and cost-effective noninvasive brain stimulation (NIBS) tool for future applications on upregulating the human language faculty. HighlightsO_LIThe first study that applies tPBM to (complex) sentence processing. C_LIO_LItPBM enhances sentence processing performances in both Mandarin L1 & L2 speakers. C_LIO_LItPBM directly enhances sentence processing without the interference of verbal WM. C_LIO_LIA causal role of LPFC for sentence processing through active tPBM. C_LIO_LIOpening up the promising application prospect for tPBM on sentence processing. C_LI

neuroscience↗

Early evolution of the ecdysozoan body plan

Extant ecdysozoans (moulting animals) are represented by a great variety of vermiform or articulated organisms. However, controversies remain about the nature of their ancestral body plan although the vermiform hypothesis seems to prevail. We describe here Beretella spinosa gen et sp. nov. a tiny ecdysozoan from the early Cambrian, Yanjiahe Formation, South China, with an unusual sack-like appearance, single opening, and spiny ornament. Beretella has no equivalent among animals, except Saccorhytus from the basal Cambrian. Phylogenetic analyses resolve both forms as a sister group (Saccorhytida) to all known Ecdysozoa, thus suggesting that ancestral ecdysozoans may have been non-vermiform animals. Saccorhytids are likely to represent an early dead-end off-shot along the stem-line Ecdysozoa that possibly evolved through anatomical simplification (e.g. lack of anus). Although extinct during the Cambrian, this animal lineage provides precious insight into the early evolution of Ecdysozoa and the nature (possibly non-vermiform) of the earliest representatives of the group.

paleontology↗

Unveiling the regulatory role of GRP7 in ABA signal-mediated mRNA translation efficiency regulation

Abscisic acid (ABA) is a crucial phytohormone involved in plant growth and stress responses. Although ABA has been implicated in the regulation of translation efficiency in Arabidopsis thaliana, the underlying mechanism remains largely unknown. In this study, we discovered that ABA treatment modulates globally translation efficiency (TE) by affecting pre-rRNA processing in the nucleolus and ribosome distribution status in the cytoplasm. The regulation of TE by ABA was largely abolished in mutants of ABA signaling core components, such as receptors PYRABACTIN RESISTANCE1/PYRABACTIN-LIKE/REGULATORY COMPONENTS OF ABA RECEPTORS (PYR/PYL/RACRs), the protein phosphatase 2Cs (PP2Cs), and the SNF1-related protein kinase 2s (SnRK2s). ABA treatment reduced the protein levels of glycine-rich RNA binding protein 7 (GRP7) in the signaling core components-dependent manner. Ribo-seq and CLIP-seq analyses unveiled GRP7s role in governing the TE of a substantial proportion of ABA-regulated genes, although independent of directly binding to the respective mRNAs. Furthermore, GRP7 directly bound to pre-rRNA and interacted with Ribosomal protein S6 (RPS6A), RPS14A and RPL36aA in the nucleolus to regulate rRNA processing. Additionally, GRP7 associated with mature polysome in the cytoplasm and is hypersensitive to translation inhibitor anisomycin when loss of function. Collectively, our study unveils the role of GRP7 in mediating translation regulation in ABA signaling, providing a novel regulatory model for plants to response to environmental stresses.

plant biology↗

Antibiotics affect the pharmacokinetics of n-butylphthalide in vivo by altering the intestinal microbiota

ObjectiveN-butylphthalide (NBP) is a monomeric compound extracted from natural plant celery seeds, whether intestinal microbiota alteration can modify its pharmacokinetics is still unclear. The purpose of this study is to investigate the effect of intestinal microbiota alteration on the pharmacokinetics of NBP and its related mechanisms. MethodsAfter treatment with antibiotics and probiotics, plasma NBP concentrations in SD rats were determined by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The effect of intestinal microbiota changes on NBP pharmacokinetics was compared. Intestinal microbiota changes after NBP treatment were analyzed by 16S rRNA sequencing. Expressions of CYP3A1 mRNA and protein in the liver and small intestine tissues under different intestinal flora conditions were determined by qRT-PCR and Western Blot. KEGG analysis was used to analyze the effect of intestinal microbiota changes on metabolic pathways. ResultsCompared to the control group, the values of Cmax, AUC0-8, AUC0-{infty}, t1/2 in the antibiotic group increased by 56.1% (P<0.001), 56.4% (P<0.001), 53.2% (P<0.001), and 24.4% (P<0.05), respectively. In contrast, the CL and Tmax values decreased by 57.1% (P<0.001) and 28.6% (P<0.05), respectively. Treatment with antibiotics could reduce the richness and diversity of the intestinal microbiota. CYP3A1 mRNA and protein expressions in the small intestine of the antibiotic group were 61.2% and 66.1% of those of the control group, respectively. CYP3A1 mRNA and protein expressions in the liver were 44.6% and 63.9% of those in the control group, respectively. There was no significant change in the probiotic group. KEGG analysis showed that multiple metabolic pathways were significantly down-regulated in the antibiotic group. Among them, the pathways of drug metabolism, bile acid biosynthesis and decomposition, and fatty acid synthesis and decomposition were related to NBP biological metabolism. ConclusionAntibiotic treatment could affect the intestinal microbiota, decrease CYP3A1 mRNA and protein expressions and increase NBP exposure in vivo by inhibiting pathways related to NBP metabolism.

pharmacology and toxicology↗